405 results on '"L. Jakab"'
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2. The in vitro effect of Garden Thyme (Thymus vulgaris L.) extract on Brachyspira hyodysenteriae
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J. Kutasi, V. Jurkovich, L. Jakab, and Pál Rafai
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Swine Diseases ,0301 basic medicine ,General Immunology and Microbiology ,biology ,Plant Extracts ,Swine ,030106 microbiology ,Microbial Sensitivity Tests ,General Medicine ,Swine dysentery ,biology.organism_classification ,Bactericidal effect ,In vitro ,Anti-Bacterial Agents ,Microbiology ,Thymus Plant ,03 medical and health sciences ,Brachyspira ,In vivo ,Brachyspira hyodysenteriae ,Animals ,Gram-Negative Bacterial Infections ,Thymus vulgaris L - Abstract
Filtrates of a water extract of commercially available garden thyme (Thymus vulgaris L.) were used for studying its possible bactericidal effect on Brachyspira hyodysenteriae, the causative agent of swine dysentery, by agar-diffusion technique. Five of the six studied Brachyspira strains have proven to be sensitive and one moderately sensitive in the in vitro tests. It was concluded that water extract of garden thyme possesses inhibitory effects against B. hyodysenteriae. In vivo experiments are needed to check the validity of this conclusion.
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- 2016
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3. The Published Writings of Wilbur and Orville Wright
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Peter L. Jakab, Rick Young, Peter L. Jakab, and Rick Young
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For the first time, nearly seventy of Wilbur and Orville Wright's published writings are brought together in a single, annotated reference. Spanning the decades from the brothers'turn-of-the-century experiments with gliders until Orville's death in 1948, the articles describe the design of their aircraft, early test flights, and camp life at Kitty Hawk. Because Wilbur's sudden death in 1912 ended any hope that the Wrights would produce a book of their own, the articles collected in this volume are their only published words.
- Published
- 2016
4. Characterization of CFTR High Expresser cells in the intestine
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Anne Collaco, Nadia A. Ameen, and Robert L. Jakab
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Male ,medicine.medical_specialty ,Sodium-Hydrogen Exchangers ,Physiology ,Qa-SNARE Proteins ,Cystic Fibrosis Transmembrane Conductance Regulator ,Biology ,Rats sprague dawley ,Rats, Sprague-Dawley ,Intestinal mucosa ,Mucosal Biology ,Physiology (medical) ,Internal medicine ,Intestine, Small ,Cyclic AMP ,medicine ,Animals ,Solute Carrier Family 12, Member 2 ,Intestinal Mucosa ,Microvilli ,integumentary system ,Hepatology ,Sodium-Hydrogen Exchanger 3 ,Gastroenterology ,Alkaline Phosphatase ,Molecular biology ,Acetylcholine ,Cystic fibrosis transmembrane conductance regulator ,Rats ,Transport protein ,Protein Transport ,Sodium–hydrogen antiporter ,Endocrinology ,biology.protein ,Alkaline phosphatase ,Sodium-Potassium-Exchanging ATPase - Abstract
The CFTR High Expresser (CHE) cells express eightfold higher levels of the cystic fibrosis transmembrane conductance regulator (CFTR) Cl−channel compared with neighboring enterocytes and were first identified by our laboratory (Ameen et al., Gastroenterology 108: 1016, 1995). We used double-label immunofluorescence microscopy to further study these enigmatic epithelial cells in rat intestine in vivo or ex vivo. CHE cells were found in duodenum, most frequent in proximal jejunum, and absent in ileum and colon. CFTR abundance increased in CHE cells along the crypt-villus axis. The basolateral Na+K+Cl−cotransporter NKCC1, a key transporter involved in Cl−secretion, was detected at similar levels in CHE cells and neighboring enterocytes at steady state. Microvilli appeared shorter in CHE cells, with low levels of Myosin 1a, a villus enterocyte-specific motor that retains sucrase/isomaltase in the brush-border membrane (BBM). CHE cells lacked alkaline phosphatase and absorptive villus enterocyte BBM proteins, including Na+H+exchanger NHE3, Cl−/HCO3−exchanger SLC26A6 (putative anion exchanger 1), and sucrase/isomaltase. High levels of the vacuolar-ATPase proton pump were observed in the apical domain of CHE cells. Levels of the NHE regulatory factor NHERF1, Na-K-ATPase, and Syntaxin 3 were similar to that of neighboring enterocytes. cAMP or acetylcholine stimulation robustly increased apical CFTR and basolateral NKCC1 disproportionately in CHE cells relative to neighboring enterocytes. These data strongly argue for a specialized role of CHE cells in Cl−-mediated “high-volume” fluid secretion on the villi of the proximal small intestine.
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- 2013
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5. Cell-specific effects of luminal acid, bicarbonate, cAMP, and carbachol on transporter trafficking in the intestine
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Anne Collaco, Nadia A. Ameen, and Robert L. Jakab
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Male ,medicine.medical_specialty ,Sodium-Hydrogen Exchangers ,Sodium-Potassium-Chloride Symporters ,Physiology ,Enterocyte ,media_common.quotation_subject ,8-Bromo Cyclic Adenosine Monophosphate ,Cystic Fibrosis Transmembrane Conductance Regulator ,Bicarbonate transporter protein ,Biology ,digestive system ,Rats, Sprague-Dawley ,Intestinal mucosa ,Mucosal Biology ,Physiology (medical) ,Internal medicine ,medicine ,Animals ,Humans ,Solute Carrier Family 12, Member 2 ,Intestinal Mucosa ,Internalization ,Ion transporter ,media_common ,Epithelial polarity ,Hepatology ,Sodium-Hydrogen Exchanger 3 ,Sodium-Bicarbonate Symporters ,Gastroenterology ,S cell ,Rats ,Intestines ,Bicarbonates ,Protein Transport ,Sodium–hydrogen antiporter ,Endocrinology ,medicine.anatomical_structure ,Carbachol ,Acids - Abstract
Changes in intestinal luminal pH affect mucosal ion transport. The aim of this study was to compare how luminal pH and specific second messengers modulate the membrane traffic of four major ion transporters (CFTR, NHE3, NKCC1, and NBCe1) in rat small intestine. Ligated duodenal, jejunal, and ileal segments were infused with acidic or alkaline saline, 8-Br-cAMP, or the calcium agonist carbachol in vivo for 20 min. Compared with untreated intestine, lumen pH was reduced after cAMP or carbachol and increased following HCO3−-saline. Following HCl-saline, lumen pH was restored to control pH levels. All four secretory stimuli resulted in brush-border membrane (BBM) recruitment of CFTR in crypts and villi. In villus enterocytes, CFTR recruitment was coincident with internalization of BBM NHE3 and basolateral membrane recruitment of the bicarbonate transporter NBCe1. Both cAMP and carbachol recruited NKCC1 to the basolateral membrane of enterocytes, while luminal acid or HCO3−retained NKCC1 in intracellular vesicles. Luminal acid resulted in robust recruitment of CFTR and NBCe1 to their respective enterocyte membrane domains in the upper third of the villi; luminal HCO3−induced similar membrane changes lower in the villi. These findings indicate that each stimulus promotes a specific transporter trafficking response along the crypt-villus axis. This is the first demonstration that physiologically relevant secretory stimuli exert their actions in villus enterocytes by membrane recruitment of CFTR and NBCe1 in tandem with NHE3 internalization.
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- 2012
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6. Deactivation of T-2 toxin in broiler ducks by biotransformation
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Z. Papp, L. Jakab, Pál Rafai, E. Brydl, and J. Kutasi
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Protective capacity ,Chromatography ,biology ,Toxin ,Feed additive ,Broiler ,medicine.disease_cause ,Animal science ,Biotransformation ,Concanavalin A ,medicine ,biology.protein ,Animal Science and Zoology ,Blood parameters ,Phytohaemagglutinin - Abstract
SUMMARY Effects of 2 dietary levels (0.6 and 1.0 ppm) of T-2 toxin, and the possible protective capacity of a mycotoxin-inactivating feed additive (Detoxa Plus) were investigated in growing White Pekin ducklings in a 49-d trial comprising 6 treatment groups of 10 ducks/group. The experimental design consisted of 1 negative and 1 positive control and 4 test groups, as follows: group 1, negative control (no T-2 toxin and no feed additive added to the feeds); group 2, positive control (no T-2 toxin added, but the feeds were supplemented with feed additive at 2 kg/t); group 3, feeds were complemented with 0.6 ppm of purified T-2 toxin (no feed additive added); group 4, feeds were complemented with 0.6 ppm of T-2 toxin and 2 kg/t of the feed additive was provided; group 5, feeds were complemented with 1.0 ppm of T-2 toxin (no feed additive added); group 6, feeds were complemented with 1.0 ppm of T-2 toxin and 2 kg/t of the feed additive was provided. From wk 4 until the end of the trial, the daily BW gain of group 3 ducks was inferior to that of control ducks, and the differences in means were statistically significant (P ≤ 0.05) at wk 4 and 7. The final BW of this group was also significantly lower than that of the control (P ≤ 0.001). The BW gain of ducks in group 5 was also depressed by the toxin treatment. The adverse effect of 0.6 ppm of T-2 toxin was fully counteracted by the feed additive in terms of daily BW gain, cumulative daily BW gain, and BW at exsanguination. The T-2 toxin at both treatment levels depressed the blastogenic response of lymphocytes to nonspecific mitogens (concanavalin A and phytohaemagglutinin), which was counteracted by the feed additive at the lower dietary concentration of T-2 toxin. No such effect was observed with 1.0 ppm of T-2 toxin. Metabolic blood parameters and hematological data showed no consistent treatment effects. We conclude that this feed additive is able to counteract the adverse effects of T-2 toxin at dietary concentrations that might be encountered under field conditions.
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- 2012
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7. Physiological relevance of cell-specific distribution patterns of CFTR, NKCC1, NBCe1, and NHE3 along the crypt-villus axis in the intestine
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Nadia A. Ameen, Anne Collaco, and Robert L. Jakab
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Male ,medicine.medical_specialty ,Sodium-Hydrogen Exchangers ,Sodium-Potassium-Chloride Symporters ,Physiology ,Bicarbonate ,Sodium ,Crypt ,Cystic Fibrosis Transmembrane Conductance Regulator ,chemistry.chemical_element ,digestive system ,Cystic fibrosis ,chemistry.chemical_compound ,Intestinal mucosa ,Physiology (medical) ,Internal medicine ,Intestine, Small ,medicine ,Animals ,Solute Carrier Family 12, Member 2 ,Intestinal Mucosa ,Goblet cell ,Hepatology ,biology ,Sodium-Hydrogen Exchanger 3 ,Sodium-Bicarbonate Symporters ,digestive, oral, and skin physiology ,Gastroenterology ,medicine.disease ,digestive system diseases ,Cystic fibrosis transmembrane conductance regulator ,Rats ,Cell biology ,Liver and Biliary Tract ,medicine.anatomical_structure ,Endocrinology ,chemistry ,biology.protein ,Carbachol ,Cotransporter - Abstract
We examined the cell-specific subcellular expression patterns for sodium- and potassium-coupled chloride (NaK2Cl) cotransporter 1 (NKCC1), Na+bicarbonate cotransporter (NBCe1), cystic fibrosis transmembrane conductance regulator (CFTR), and Na+/H+exchanger 3 (NHE3) to understand the functional plasticity and synchronization of ion transport functions along the crypt-villus axis and its relevance to intestinal disease. In the unstimulated intestine, all small intestinal villus enterocytes coexpressed apical CFTR and NHE3, basolateral NBCe1, and mostly intracellular NKCC1. All (crypt and villus) goblet cells strongly expressed basolateral NKCC1 (at approximately three-fold higher levels than villus enterocytes), but no CFTR, NBCe1, or NHE3. Lower crypt cells coexpressed apical CFTR and basolateral NKCC1, but no NHE3 or NBCe1 (except NBCe1-expressing proximal colonic crypts). CFTR, NBCe1, and NKCC1 colocalized with markers of early and recycling endosomes, implicating endocytic recycling in cell-specific anion transport. Brunner's glands of the proximal duodenum coexpressed high levels of apical/subapical CFTR and basolateral NKCC1, but very low levels of NBCe1, consistent with secretion of Cl−-enriched fluid into the crypt. The cholinergic agonist carbachol rapidly (within 10 min) reduced cell volume along the entire crypt/villus axis and promoted NHE3 internalization into early endosomes. In contrast, carbachol induced membrane recruitment of NKCC1 and CFTR in all crypt and villus enterocytes, NKCC1 in all goblet cells, and NBCe1 in all villus enterocytes. These observations support regulated vesicle traffic in Cl−secretion by goblet cells and Cl−and HCO3−secretion by villus enterocytes during the transient phase of cholinergic stimulation. Overall, the carbachol-induced membrane trafficking profile of the four ion transporters supports functional plasticity of the small intestinal villus epithelium that enables it to conduct both absorptive and secretory functions.
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- 2011
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8. Note: 4-bounce neutron polarizer for reflectometry applications
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J. Fuzi, Béla Nagy, Tamás Veres, László Bottyán, L. Jakab, and Dániel G. Merkel
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010302 applied physics ,Physics ,business.industry ,02 engineering and technology ,Polarizer ,021001 nanoscience & nanotechnology ,Polarization (waves) ,01 natural sciences ,law.invention ,Optical axis ,Optics ,law ,Harmonics ,0103 physical sciences ,Incident beam ,Neutron ,0210 nano-technology ,business ,Reflectometry ,Instrumentation - Abstract
A neutron polarizer using four successive reflections on m = 2.5 supermirrors was built and installed at the GINA neutron reflectometer at the Budapest Neutron Centre. This simple setup exhibits 99.6% polarizing efficiency with 80% transmitted intensity of the selected polarization state. Due to the geometry, the higher harmonics in the incident beam are filtered out, while the optical axis of the beam remains intact for easy mounting and dismounting the device in an existing experimental setup.
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- 2018
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9. α-AP-2 Directs Myosin VI-dependent Endocytosis of Cystic Fibrosis Transmembrane Conductance Regulator Chloride Channels in the Intestine
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Mark S. Mooseker, Nadia A. Ameen, Peter S. Hegan, Robert L. Jakab, and Anne Collaco
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Male ,Endocytic cycle ,Cystic Fibrosis Transmembrane Conductance Regulator ,Endocytosis ,Models, Biological ,Biochemistry ,Clathrin ,Rats, Sprague-Dawley ,Terminal web ,Mice ,Chloride Channels ,Myosin ,Animals ,Intestinal Mucosa ,Molecular Biology ,Actin ,Adaptor Proteins, Signal Transducing ,Mice, Knockout ,Microvilli ,Myosin Heavy Chains ,biology ,Cell Biology ,Cystic fibrosis transmembrane conductance regulator ,Rats ,Cell biology ,Adaptor Proteins, Vesicular Transport ,Enterocytes ,Transcription Factor AP-2 ,Chloride channel ,biology.protein ,Apoptosis Regulatory Proteins - Abstract
The actin motor myosin VI regulates endocytosis of cystic fibrosis transmembrane conductance regulator (CFTR) in the intestine, but the endocytic adaptor linking CFTR to myosin VI is unknown. Dab2 (Disabled 2) is the binding partner for myosin VI, clathrin, and alpha-AP-2 and directs endocytosis of low density lipoprotein receptor family members by recognizing a phosphotyrosine-binding domain. However, CFTR does not possess a phosphotyrosine-binding domain. We examined whether alpha-AP-2 and/or Dab2 were binding partners for CFTR and the role of myosin VI in localizing endocytic adaptors in the intestine. CFTR co-localized with alpha-AP-2, Dab2, and myosin VI and was identified in a complex with all three endocytic proteins in the intestine. Apical CFTR was increased in the intestines of Dab-2 KO mice, suggesting its involvement in regulating surface CFTR. Glutathione S-transferase pulldown assays revealed binding of CFTR to alpha-AP-2 (but not Dab2) in the intestine, whereas Dab-2 interacted with alpha-AP-2. siRNA silencing of alpha-AP-2 in cells significantly reduced CFTR endocytosis, further supporting alpha-AP-2 as the direct binding partner for CFTR. alpha-AP-2 and Dab2 localized to the terminal web regions of enterocytes, but Dab2 accumulated in this location in Snell's Waltzer myosin VI((sv/sv)) intestine. Ultrastructural examination revealed that the accumulation of Dab2 correlated with prominent involution and the loss of normal positioning of the intermicrovillar membranes that resulted in expansion of the terminal web region in myosin VI((sv/sv)) enterocytes. The findings support alpha-AP-2 in directing myosin VI-dependent endocytosis of CFTR and a requirement for myosin VI in membrane invagination and coated pit formation in enterocytes.
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- 2010
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10. Sequence of pituitary–adrenal cortical hormone responses to low-dose physostigmine administration in young adult women and men
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R. Kenneth Czambel, Robert L. Jakab, Thomas H. Miller, Michael E. Rhodes, and Robert T. Rubin
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Adult ,Male ,endocrine system ,medicine.medical_specialty ,Physostigmine ,Time Factors ,Hydrocortisone ,Pituitary-Adrenal System ,Adrenocorticotropic hormone ,General Biochemistry, Genetics and Molecular Biology ,Sex Factors ,Adrenocorticotropic Hormone ,Reference Values ,Internal medicine ,medicine ,Humans ,General Pharmacology, Toxicology and Pharmaceutics ,Young adult ,Cholinesterase ,Dose-Response Relationship, Drug ,biology ,business.industry ,General Medicine ,Arginine Vasopressin ,Dose–response relationship ,Endocrinology ,Area Under Curve ,biology.protein ,Female ,Cholinesterase Inhibitors ,business ,hormones, hormone substitutes, and hormone antagonists ,Blood sampling ,Hormone ,medicine.drug - Abstract
We previously demonstrated greater HPA axis activation in adult men compared to adult women following low-dose administration of the anticholinesterase inhibitor, physostigmine (PHYSO). Because blood sampling was done infrequently following PHYSO, the rise times of AVP, ACTH1-39, and cortisol could not be determined. In the present study, we determined the sequence of hormone increases by frequent blood sampling following PHYSO. Twelve adult women and 12 adult men underwent three test sessions 5-7 days apart: PHYSO, saline control, and repeat PHYSO. As in the earlier study, PHYSO produced no side effects in half the subjects and mild side effects in the other half, with no significant female-male differences. None of the hormone responses was significantly correlated with the presence or absence of side effects. In both women and men, the AVP increase preceded the ACTH1-39 increase, which in turn preceded the cortisol increase. The AVP and ACTH AUCs were significantly positively correlated in both women and men, supporting AVP as an acute stimulus to ACTH secretion. Also as in the earlier study, the AVP response to PHYSO was more than twice as great in men as in women, but the difference was not statistically significant. We therefore analyzed the results of both studies combined (N=26 women and 26 men). The men had a significantly greater AVP response and a trend toward a greater ACTH1-39 response compared to the women. These findings further support the concept of sexual diergism (functional sex difference) in the influence of CNS cholinergic systems on HPA hormone secretion.
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- 2006
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11. Embedded motor drive prototype platform for testing control algorithms
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Calin Rusu, Mircea M. Radulescu, Zsolt L. Jakab, Radian K. Melinda, and Szöke Enikö
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Engineering ,Motor drive ,Control algorithm ,business.industry ,Embedded system ,Control engineering ,business - Published
- 2014
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12. Locator/Identifier Separation Protocol (LISP) Network Element Deployment Considerations
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L. Jakab, A. Cabellos-Aparicio, F. Coras, J. Domingo-Pascual, and D. Lewis
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- 2014
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13. l-ephedrine-induced neurodegeneration in the parietal cortex and thalamus of the rat is dependent on hyperthermia and can be altered by the process of in vivo brain microdialysis
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Sherry A. Ferguson, Robert L. Jakab, Keri J Hopkins, and John F. Bowyer
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Male ,medicine.medical_specialty ,Microdialysis ,Dextroamphetamine ,Fever ,Tyrosine 3-Monooxygenase ,Biology ,Toxicology ,Rats, Sprague-Dawley ,Thalamus ,Dopamine ,Parietal Lobe ,Internal medicine ,Basal ganglia ,medicine ,Animals ,Ephedrine ,Amphetamine ,Putamen ,Neurodegeneration ,Neurotoxicity ,Neurodegenerative Diseases ,General Medicine ,medicine.disease ,Rats ,Endocrinology ,Anesthesia ,Caudate Nucleus ,medicine.drug - Abstract
Multiple doses of the dietary supplement l -ephedrine can cause severe hyperthermia and modest dopamine depletions in the rat brain. Since d -amphetamine treatment can result in neurodegeneration, the potential of l -ephedrine to produce similar types of degeneration was investigated. Adult male rats, some implanted in the caudate/putamen (CPu) for microdialysis, were given four doses of 25 mg/kg l -ephedrine or 5 mg/kg d -amphetamine (2 h between doses) at an ambient temperature of 23 °C. l -ephedrine-induced degeneration in the forebrain was dependent on the degree of hyperthermia. Layer IV of the parietal cortex was the most sensitive to l -ephedrine treatment with peak body temperatures of at most 40.0 °C necessary to produce degeneration. Extensive neurodegeneration in the parietal cortex after l -ephedrine treatment was as pronounced as that previously described for d -amphetamine treatment and also occurred in the intralaminar, ventromedial and ventrolateral thalamic nuclei in rats with severe hyperthermia (peak body temperatures>41.0 °C). The neurodegeneration induced by l -ephedrine may have resulted in part from excitotoxic mechanisms involving the indirect pathways of the basal ganglia and related areas. No differences were observed between microdialysis and non-implanted rats with respect to degree of tyrosine hydroxylase (TH) loss in the CPu after either d -amphetamine or l -ephedrine treatment. However, neurodegeneration resulting from d -amphetamine and l -ephedrine was reduced in the microdialysis animals in the hemisphere ipsilateral to the probe, which raises concerns when using the technique of in vivo microdialysis to evaluate neurodegeneration. The results of this study, in conjunction with human clinical evaluation of ephedrine neurotoxicity, indicate that regionally specific damage may occur in the cortex of some humans exposed to ephedrine in the absence of stroke or hemorrhage.
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- 2001
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14. Estrogen receptor ? immunoreactivity in differentiating cells of the developing rat cerebellum
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Jeremy K. Wong, Scott M. Belcher, and Robert L. Jakab
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Messenger RNA ,medicine.medical_specialty ,medicine.diagnostic_test ,General Neuroscience ,Purkinje cell ,Immunocytochemistry ,Estrogen receptor ,Golgi apparatus ,Biology ,symbols.namesake ,medicine.anatomical_structure ,Endocrinology ,nervous system ,Western blot ,Internal medicine ,symbols ,medicine ,Estrogen receptor beta ,Immunostaining - Abstract
Estrogen receptors (ER) play a significant role in the development of some regions of the mammalian brain. Recently, ER-beta (ERβ) mRNA and protein were shown to be expressed in the rat cerebellum. In the present study, the ontogeny of ERβ protein expression was examined in the rat cerebellum during postnatal development. Western blot analysis indicated that a single ERβ-like immunoreactive species of ∼55 kDa was present in protein lysates prepared from the cerebella of female and male Sprague-Dawley rat pups. Immunocytochemical analysis of cerebellar sections from the midline vermis revealed that during development, the expression of ERβ varied with age and cell-type, but not sex. In the developing cerebellum, highest levels of ERβ-immunoreactivity (IR) were detected in neurons during neurite growth, and in some glia during migration. Throughout the first postnatal week, ERβ-IR was localized to differentiating granule cells in the external germinal layer and to migrating glia. Differentiating granule cells expressed detectable levels of ERβ throughout development. In Purkinje cells, ERβ-IR was first detected on postnatal day 6 (P6), with peak intensities of immunostaining coinciding with the initiation of axonal and dendritic growth that occurs between P7 and P8. Expression of ERβ-IR remained high during maturation of Purkinje cell dendrites, and then decreased to a lower level maintained in the adult. From the third postnatal week, ERβ-IR was also detected in the later developing Golgi, stellate, and basket neurons. These results suggest that ERβ may play a role in growth-related mechanisms during differentiation of cerebellar neurons and glia. J. Comp. Neurol. 430:396–409, 2001. © 2001 Wiley-Liss, Inc.
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- 2001
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15. Segregation of serotonin 5-HT2A and 5-HT3 receptors in inhibitory circuits of the primate cerebral cortex
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Patricia S. Goldman-Rakic and Robert L. Jakab
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biology ,musculoskeletal, neural, and ocular physiology ,General Neuroscience ,food and beverages ,Inhibitory postsynaptic potential ,Substance-P Receptor ,medicine.anatomical_structure ,nervous system ,Cerebral cortex ,biology.protein ,medicine ,GABAergic ,Serotonin ,Receptor ,Neuroscience ,Parvalbumin ,5-HT receptor - Abstract
An emerging concept of cortical network organization is that distinct segments of the pyramidal neuron tree are controlled by functionally diverse inhibitory microcircuits. We compared the expression of two serotonin receptor subtypes, the G-protein-coupled 5-hydroxytryptamine2A receptors and the ion-channel gating 5-HT3 receptors, in cortical neuron types, which control these microcircuits. Here we show, using light and electron microscopic immunocytochemical techniques, that 5-HT2A receptors are segregated from 5-HT3 receptors in the macaque cerebral cortex. 5-HT2A receptor immunolabel was found in pyramidal cells and also in GABAergic interneurons known to specialize in the perisomatic inhibition of pyramidal cells: large and medium-size parvalbumin- and calbindin-containing interneurons. In contrast, 5-HT3 label was only present in small GABA-, substance P receptor-, and calbindin-containing neurons and in medium-size calretinin-containing neurons: interneurons known to preferentially target the dendrites of pyramidal cells. This cellular segregation indicates a serotonin-receptor-specific segmentation of the GABAergic inhibitory actions along the pyramidal neuron tree.
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- 2000
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16. Wood to Metal: The Structural Origins of the Modern Airplane
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Peter L. Jakab
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Engineering ,business.product_category ,Aeronautics ,business.industry ,Aircraft manufacturing ,Aerospace Engineering ,Aerospace engineering ,business ,Cluster (spacecraft) ,Aerospace technology ,Airplane ,Landing gear - Abstract
The transition from the wood-and-fabric airplane to the all-metal airplane was essentially complete by World War II. The late 1920s and early 1930s are said to have witnessed a structural revolution in aeronautics with the appearance of streamlined metal aircraft with such features as tightly cowled multiple engines, variable-pitch propellers, retracting landing gear, and stressed-skin aluminum construction. A prevalent assumption regarding this transition is that the building material acted as a primary driver of change, that engineering advance was guided by an inevitable move toward metal structures. Metal did indeed allow engineers to extend performance parameters afforded by innovative structural designs, but, interestingly, many of these key innovations were not developed to takeadvantageof metal. They emerged independent of theconstruction material, and often weree rst used in wooden airplanes. The cluster of original ideas that coalesced in the 1930s constituted one of the major watershedperiodsin aerospacetechnology.Metalcarriedthisbasicdesign revolutiontothelimitsofitsengineering andtechnicalfeasibility,butonlyafteranewfoundationwasinplace.Metaldidnotspawnthestructuralrevolution. An exploration of therootsof the structural revolution in aeronautics and thecomplexity oftechnological progress is presented.
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- 1999
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17. Quantitative Three-Dimensional Analysis of the Catecholaminergic Innervation of Identified Neurons in the Macaque Prefrontal Cortex
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Patricia S. Goldman-Rakic, Leonid S. Krimer, and Robert L. Jakab
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Tyrosine 3-Monooxygenase ,Prefrontal Cortex ,Dendrite ,Biology ,chemistry.chemical_compound ,Catecholamines ,medicine ,Animals ,Prefrontal cortex ,Fluorescent Dyes ,Neurons ,Catecholaminergic ,Lucifer yellow ,Pyramidal Cells ,General Neuroscience ,Dopaminergic ,Articles ,Anatomy ,Isoquinolines ,Macaca mulatta ,Microscopy, Electron ,medicine.anatomical_structure ,chemistry ,Basal dendrite ,Excitatory postsynaptic potential ,Neuron - Abstract
The present study provides a complete quantitative three-dimensional analysis of neurons in primate prefrontal cortex targeted by catecholaminergic axons. Individual pyramidal and nonpyramidal cells in fixed slices were filled with Lucifer yellow (LY) and recovered with anti-LY antibody combined with anti-tyrosine hydroxylase (TH) antisera to reveal catecholaminergic axons. The total number of TH contacts and TH apposition density (THAD) was obtained for pyramidal and nonpyramidal cells in different layers. Four TH contacts (two on spines and two on shafts) were selected for correlated electron microscopic examination and serially sectioned; all four were confirmed as membrane appositions. Quantitative analysis revealed 90 TH contacts per pyramidal neuron in layer III, with a density of 0.8 per 100 μm of dendritic length (i.e., averaging one contact per basal dendrite). Remarkably, pyramids of layers III, V, and VI had the same THAD values, with a highly regular distribution of TH terminals on their spiny dendritic trees. In contrast, TH contacts on nonpyramidal neurons in layer III were half as dense and, moreover, were distributed irregularly and showed large variation from cell to cell. Neurons in layers II and superficial III had the highest THAD, as compared with deeper layers (1.4 vs 0.7 per 100 μm of dendritic length for pyramids; 0.53 vs 0.4 for interneurons). The highly organized TH innervation of pyramidal neurons, with at least one contact on virtually every dendrite, indicates that catecholaminergic, presumably dopaminergic, terminals are placed strategically along the entire dendritic tree to modulate most, if not all, of the excitatory input of a neuron. At the same time, the sparsity of contacts per dendrite may explain cortical vulnerability in diseases involving dopamine.
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- 1997
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18. Aromatase in axonal processes of early postnatal hypothalamic and limbic areas including the cingulate cortex
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Evan R. Simpson, Tamas L. Horvath, Lucia Roa-Peña, Robert L. Jakab, and Frederick Naftolin
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Cingulate cortex ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Cell Biology ,Biology ,Biochemistry ,Amygdala ,Diagonal band of Broca ,Stria terminalis ,Endocrinology ,medicine.anatomical_structure ,Limbic system ,nervous system ,Hypothalamus ,Internal medicine ,Forebrain ,medicine ,biology.protein ,Molecular Medicine ,Aromatase ,Molecular Biology ,Neuroscience - Abstract
It has been shown that sexual dimorphic morphology of certain hypothalamic and limbic areas underlie gender-specific sexual behavior and neuroendocrine mechanisms. The key role played by locally formed estrogen in these developmental events has been revealed during a critical perinatal period. In this study, we aimed to document the presence of estrogen-synthetase (aromatase)-immunoreactive elements in the involved limbic system and hypothalamus of the developing rat brain. On postnatal day 5, animals of both sexes were perfusion-fixed, and sections from the forebrain and hypothalamus were immunolabelled for aromatase using an antiserum that was generated against a 20 amino acid sequence of placental aromatase. Aromatase-immunoreactivity was present in neuronal perikarya and axonal processes in the following limbic structures: the central and medial nuclei of the amygdala, stria terminalis, bed nucleus of the stria terminalis (BNST), lateral septum, medial septum, diagonal band of Broca, lateral habenula and all areas of the limbic (cingulate) cortex. In the hypothalamus, the most robust labelling was observed in the medial preoptic area, periventricular regions, ventromedial and arcuate nuclei. The most striking feature of the immunostaining with this antiserum was its intracellular distribution. In contrast to the heavy perikaryal labelling that can be observed with most of the currently available aromatase antisera, in the present experiments, immunoperoxidase was predominantly localized to axons and axon terminals. All the regions with fiber staining corresponded to the projection fields of neuron populations that have previously been found to express perikaryal aromatase. Our results confirm the presence of aromatase-immunoreactivity in developing limbic and hypothalamic areas. The massive expression of aromatase in axonal processes raises the possibility that estrogen formed locally by aromatase may not only regulate the growth, pathfinding and target recognition of its host neuronal processes, but may also exert paracrine actions on structures in close proximity, including the target cells.
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- 1997
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19. Otto Lilienthal - 'The Greatest of the Precursors'
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Peter L. Jakab
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Engineering ,Wright ,Operations research ,business.industry ,Art history ,Aerospace Engineering ,Brief treatment ,business - Abstract
This brief treatment of Otto Lilienthal's overall aeronautical contribution details his aerodynamic research, the data as well as his data-gathering technique. Lilienthal's subsequent glider experiments also are covered from the perspective of both their technical and inspirational contributions. The heart of the paper is a discussion of the place of Lilienthal's aerodynamics in the work of others, primarily the Wright brothers. Included is a reassessment of the accuracy of Lilienthal's famous table of lift coefficients and the assumptions that the Wrights made in using Lilienthal's data. Historically, Lilienthal's data and their use by the Wrights has been one of the more complex and debated aspects of the Wright story. The article presents a brief review of how Lilienthal's contrihution has been characterized and revised over time, with a discussion of the current thinking regarding the famous Lilienthal table of lift coefficients.
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- 1997
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20. Morphogenetic Plasticity of Neuronal Elements in Cerebellar Glomeruli during Deafferentation-Induced Synaptic Reorganization
- Author
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Robert L. Jakab, József Takács, and József Hámori
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Male ,Biology ,Inhibitory postsynaptic potential ,Article ,Cerebellar Cortex ,Nerve Fibers ,Synaptic augmentation ,Neuroplasticity ,medicine ,Animals ,Neurons, Afferent ,Neurons ,Neuronal Plasticity ,Granule cell ,Denervation ,Axons ,Nerve Regeneration ,Rats ,Microscopy, Electron ,medicine.anatomical_structure ,Intercellular Junctions ,Neurology ,Cerebellar cortex ,Synaptic plasticity ,Synapses ,Cerebellar vermis ,Excitatory postsynaptic potential ,Neurology (clinical) ,sense organs ,Neuroscience - Abstract
Reorganization of the cerebellar glomerulus, the main synaptic complex within the granule cell layer, was investigated using quantitative morphological techniques. All afferents to the cerebellar cortex, including mossy-fibers, were surgically destroyed by undercutting the cerebellar vermis. Fifteen days after the operation, which resulted in the removal of the main excitatory afferent to the glomerulus, a significant reorganization of the whole synaptic complex was observed, whereas the structural integrity of the glomerulus was remarkably well preserved. This was indicated by the observation that the number of granule cell dendrites (approximately 50 per glomerulus), as well as the number of dendritic digits (approximately 210 per glomerulus) bearing most of the approximately 230 synaptic junctions per glomerulus, did not change significantly after mossy-fiber degeneration. The total number of synapses in the reorganized glomerulus did not change either, despite the disappearance of two-thirds of (excitatory) synaptic junctions caused by mossy-fiber degeneration. In the reorganized glomeruli, however, the inhibitory, GABA-containing Golgi axonal varicosities became the dominant synaptic type-about four-fifths (approximately 200) of all synapses within the glomerulus-whereas the dendritic synapses between the granule cells represented only one-fifth of all synaptic junctions. The quantitative data of the reorganized cerebellar glomerulus demonstrate both a remarkable constancy and a plasticity of the excitatory granule cells and inhibitory Golgi neurons building up this synaptic complex. Constancy (the preservation of certain specific structural features) is represented by an eventually unchanged number of dendrites and synaptic junctions within the deafferented glomerulus. Such constancy was made possible, however, by the morphogenetic plasticity of both nerve-cell types to produce new, dendro-dendritic and axo-dendritic synapses to compensate for the loss of mossy-fiber synapses.
- Published
- 1997
21. Biotransformation of trichothecenes alleviates the negative effects of T-2 toxin in pigs
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Pál Rafai, L. Jakab, and Zoltán Papp
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General Veterinary ,Chemistry ,Toxin ,Swine ,Feed additive ,Sus scrofa ,Positive control ,Food Contamination ,medicine.disease_cause ,Animal Feed ,Toxicology ,T-2 Toxin ,Animal science ,Biotransformation ,Fusarium ,medicine ,Fusarium toxins ,Animals ,medicine.symptom ,Trichothecenes ,Weight gain - Abstract
Between 49 and 70 days of age, three groups of growing pigs (n = 10 each) were fed diets containing 0, 0.3 and 0.5 mg/kg T-2 toxin, respectively, for 21 days. The feed of another two groups of pigs (n = 10 each) contained 0.3 or 0.5 mg/kg T-2 toxin, respectively, plus a feed additive developed for splitting up the molecular structure of Fusarium toxins, in particular trichothecenes, by deepoxidation of the molecule, at 2 kg/tonne concentration. One group (n = 10) served as positive control; their feed was free from T-2 toxin but contained the feed additive at the above concentration. Toxin concentrations at these low dietary levels impaired the feed intake and growth rate of pigs. The feed additive alleviated the negative effects and justified its potential for prevention. Data of the present study indicated a 0.2 mg/kg feed no observed effect level (NOEL) of T-2 toxin in growing pig feeds.
- Published
- 2013
22. Regulated traffic of anion transporters in mammalian Brunner's glands: a role for water and fluid transport
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Anne Collaco, Robert L. Jakab, Nadia Hoekstra, Amos Brooks, Kisha A. Mitchell, and Nadia A. Ameen
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Male ,Vacuolar Proton-Translocating ATPases ,Cystic Fibrosis ,Physiology ,Duodenum ,Antimicrobial peptides ,Anion Transport Proteins ,Cystic Fibrosis Transmembrane Conductance Regulator ,Brunner Glands ,Biology ,digestive system ,Second Messenger Systems ,Rats, Sprague-Dawley ,Chlorides ,Mucosal Biology ,Physiology (medical) ,medicine ,Cyclic AMP ,Animals ,Humans ,Secretion ,Ion transporter ,chemistry.chemical_classification ,Hepatology ,Gastroenterology ,Water ,Transporter ,Biological Transport ,Fluid transport ,Aquaporin 5 ,Rats ,Bicarbonates ,Celiac Disease ,medicine.anatomical_structure ,Biochemistry ,chemistry ,Brunner's glands ,Carbachol ,Protons ,Glycoprotein ,Function (biology) - Abstract
The Brunner's glands of the proximal duodenum exert barrier functions through secretion of glycoproteins and antimicrobial peptides. However, ion transporter localization, function, and regulation in the glands are less clear. Mapping the subcellular distribution of transporters is an important step toward elucidating trafficking mechanisms of fluid transport in the gland. The present study examined 1) changes in the distribution of intestinal anion transporters and the aquaporin 5 (AQP5) water channel in rat Brunner's glands following second messenger activation and 2) anion transporter distribution in Brunner's glands from healthy and disease-affected human tissues. Cystic fibrosis transmembrane conductance regulator (CFTR), AQP5, sodium-potassium-coupled chloride cotransporter 1 (NKCC1), sodium-bicarbonate cotransporter (NBCe1), and the proton pump vacuolar ATPase (V-ATPase) were localized to distinct membrane domains and in endosomes at steady state. Carbachol and cAMP redistributed CFTR to the apical membrane. cAMP-dependent recruitment of CFTR to the apical membrane was accompanied by recruitment of AQP5 that was reversed by a PKA inhibitor. cAMP also induced apical trafficking of V-ATPase and redistribution of NKCC1 and NBCe1 to the basolateral membranes. The steady-state distribution of AQP5, CFTR, NBCe1, NKCC1, and V-ATPase in human Brunner's glands from healthy controls, cystic fibrosis, and celiac disease resembled that of rat; however, the distribution profiles were markedly attenuated in the disease-affected duodenum. These data support functional transport of chloride, bicarbonate, water, and protons by second messenger-regulated traffic in mammalian Brunner's glands under physiological and pathophysiological conditions.
- Published
- 2013
23. Characterization of CFTR High Expresser (CHE) cells of the small intestine
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Robert L. Jakab and Nadia A. Ameen
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medicine.anatomical_structure ,Chemistry ,Genetics ,medicine ,Molecular Biology ,Biochemistry ,Molecular biology ,Small intestine ,Biotechnology - Published
- 2013
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24. IFP-COMPATIBLE GROUND-COVER MANAGEMENT SYSTEMS IN A NEW-PLANTED APPLE ORCHARD
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I. Merwin, E. Dorgo, T. Bubán, B. Helmeczi, L. Jakab, J. Papp, and I. Kajati
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Management system ,Environmental science ,Cover (algebra) ,Forestry ,Horticulture ,Orchard - Published
- 1996
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25. Presynaptic and postsynaptic subcellular localization of substance P receptor immunoreactivity in the neostriatum of the rat and rhesus monkey (Macaca mulatta)
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Patricia S. Goldman-Rakic and Robert L. Jakab
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Dendritic spine ,General Neuroscience ,Putamen ,education ,Neurotransmission ,Biology ,Substance-P Receptor ,Cell biology ,medicine.anatomical_structure ,nervous system ,Postsynaptic potential ,medicine ,Excitatory postsynaptic potential ,Cholinergic ,Axon ,Neuroscience - Abstract
The substance P receptor (SPR) gene is expressed at high levels in basal ganglia, but the paucity of information about localization of the encoded receptor protein has limited our understanding of this peptide's involvement in cellular and subcellular mechanisms in this region. Morphological evidence in the rodent striatum indicates that SPRs are expressed in postsynaptic neuronal elements, while pharmacological studies suggest the existence of presynaptic SPRs in this structure. We have examined the issue of subcellular distribution of this receptor protein in rat and primate neostriatal tissue, employing an antiserum raised against SPR. Electron microscopic analysis revealed that SPR immunoreactivity is present in presynaptic and postsynaptic neuronal elements in both species. In agreement with earlier studies, SPR immunoreactivity was found predominantly in perikarya and dendrites of a small subset of striatal neurons, the large and medium-sized aspiny interneurons. In addition, a small but significant proportion of the immunoreaction product was localized in presynaptic profiles, both in axons and axon terminals. The majority of SPR immunoreactive boutons formed asymmetric synapses with dendrites and dendritic spines. The association of SPRs with asymmetric synapses provides a morphological substrate for peptidergic modulation of excitatory neurotransmission of extrastriatal origin. A minor proportion of immunolabeled axons established symmetric synaptic junctions with unlabeled dendrites. The presence of SPRs in these synapses suggests a presynaptic peptidergic modulation of intrinsic striatal transmitter systems. The observations in this study also indicate that SPR mediates a complex combination of postsynaptic and presynaptic effects on acetylcholine release in the mammalian striatum. © 1996 Wiley-Liss, Inc.
- Published
- 1996
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26. Distribution and neurochemical character of substance P receptor (SPR)-immunoreactive striatal neurons of the macaque monkey: Accumulation of SP fibers and SPR neurons and dendrites in ?striocapsules? encircling striosomes
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Patricia S. Goldman-Rakic, Robert L. Jakab, and Lili‐Naz Hazrati
- Subjects
medicine.medical_specialty ,Striosome ,General Neuroscience ,education ,Biology ,Choline acetyltransferase ,Substance-P Receptor ,Immunolabeling ,Endocrinology ,nervous system ,Internal medicine ,Tachykinin receptor 1 ,medicine ,Biophysics ,biology.protein ,Cholinergic ,Receptor ,Parvalbumin - Abstract
The striatal distribution of the substance P receptor (SPR) protein was examined in relation to its ligand, the neuro-peptide SP, as well as to the neurochemical and compartmental composition of the neostriatum in rhesus monkeys (Macaca mulatta) in immunohistochemical experiments. About 2% of striatal neurons, displaying varicose, virtually spine-free dendrites characteristic of large and medium-sized aspiny interneurons, expressed SPR immunoreactivity. SPR/choline acetyltransferase, SPR/somatostatin, SPR/GABA, SPR/calbindin D28k, and SPR/parvalbumin double immunolabeling experiments demonstrated that SPR-positive cells are either cholinergic or somatostatinergic. Comparison of SP and SPR immunoreactivities in double-labeled and adjacent single-labeled sections revealed compartment-specific match and mismatch between the densities of the peptide and receptor. A matching high density of SP fibers and SPR cells and dendrites was only observed in the rim of the striosome compartments. To our knowledge, this is the first evidence for an anatomical border comprised of dendritic processes that separate striatal compartments. We have termed these zones “striocapsules,” because they encircle and encapsulate striosomal cell islands. In the striatal matrix, an abundance of SPR-labeled profiles was complemented with light SP staining. By contrast, in the core of the striosomes, SPR labeling was sparse and SP staining intense. SP-positive axon-like puncta frequently contacted SPR-positive dendrites in all striatal compartments. The SP receptor/ligand match indicates a sharp increase in the efficacy of SP action in the striocapsules, and suggests that the influence of SP might be heightened in this striatal subcompartment. © 1996 Wiley-Liss, Inc.
- Published
- 1996
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27. Aromatase Immunoreactivity in Axon Terminals of the Vertebrate Brain
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Csaba Leranth, Jacques Balthazart, Robert L. Jakab, Nobuhiro Harada, Tamas L. Horvath, and Frederick Naftolin
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medicine.medical_specialty ,biology ,Endocrine and Autonomic Systems ,medicine.drug_class ,Endocrinology, Diabetes and Metabolism ,Central nervous system ,Immunocytochemistry ,Human brain ,Synaptic vesicle ,Quail ,Cellular and Molecular Neuroscience ,Endocrinology ,medicine.anatomical_structure ,nervous system ,Estrogen ,biology.animal ,Internal medicine ,medicine ,biology.protein ,Aromatase ,Axon ,Neuroscience - Abstract
Intraneuronal production of estradiol from testosterone has been shown to play a pivotal role in gender-specific brain development of most vertebrates, and to participate in numerous functions of the adult central nervous system. Previous biochemical and morphological approaches demonstrated that estrogen synthetase (aromatase) is present in specific limbic and hypothalamic structures. On the other hand, less attention has been paid to revealing its subcellular distribution. The possibility of aromatase presence in axonal processes has been indicated by recent biochemical and morphological observations suggesting new insights for the role of aromatase in neural functions. The objective of the present study was to provide morphological evidence for the subcellular location of aromatase in neurons of different vertebrate species including Japanese quail, rat, monkey, and human. Immunocytochemistry using a purified polyclonal antiserum against human placental aromatase localized immunoreactivity to hypothalamic and limbic cell groups in all of these species. Light and electron microscopic examination of vibratome sections revealed the presence of aromatase immunoreactivity throughout the neuronal perikarya, including dendrites and axonal processes. In each species there were numerous boutons which contained labeled small clear synaptic vesicles. Many of these axon terminals formed synapses with immuno-negative and immuno-positive dendrites and perikarya. This study furnishes the first immunolocalization of aromatase in the brains of two primate species, humans and monkeys. The provision of further evidence for estrogen synthesis in axons and axon terminals may help resolve apparent differences between the measurement of aromatase activity and the lack of aromatase-immunopositive cell bodies in previous studies. The present findings may be coupled with recent evidence regarding the molecular biology and the diversity of functional properties of P450 aromatase to indicate previously unexpected effects of brain aromatase at the synaptic level.
- Published
- 1996
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28. Effect of various levels of T-2 toxin on the clinical status, performance and metabolism of growing pigs
- Author
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A Ványi, L. Jakab, S Tuboly, E Túry, Z. Papp, E. Brydl, A. Bata, and P Rafai
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Feed consumption ,Swine ,Animal feed ,Protein metabolism ,chemistry.chemical_element ,Biology ,Calcium ,Weight Gain ,medicine.disease_cause ,chemistry.chemical_compound ,Animal science ,Cations ,medicine ,Animals ,Aspartate Aminotransferases ,Inorganic phosphorus ,Swine Diseases ,Behavior, Animal ,General Veterinary ,Magnesium ,Toxin ,Body Weight ,Proteins ,General Medicine ,Metabolism ,Animal Feed ,T-2 Toxin ,Biochemistry ,chemistry ,Drug Eruptions ,Energy Intake ,Energy Metabolism - Abstract
In two sets of experiments eight groups of seven-week-old pigs weighing about 9 kg were fed for three weeks a prestarter that contained 0.5, 1.0, 2.0, 3.0, 4.0, 5.0, 10.0 or 15.0 mg/kg of highly purified T-2 toxin. The feed of the two control groups was free from T-2 toxin. Average daily intakes of toxin by the pigs were 0.38, 0.81, 1.24, 1.43, 0.93, 0.81, 0.99 and 2.5 mg, respectively. The weight gains, the feed intakes, the extent of feed refusal, the parameters of energy and protein metabolism and the serum concentrations of calcium, inorganic phosphorus and magnesium were affected to different extents by the different doses of T-2 toxin, but the data indicated that feed consumption was reduced and the activity of aspartate aminotransferase was increased by the smallest amount of T-2 toxin tested.
- Published
- 1995
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29. Lubiprostone targets prostanoid signaling and promotes ion transporter trafficking, mucus exocytosis, and contractility
- Author
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Anne Collaco, Nadia A. Ameen, and Robert L. Jakab
- Subjects
Physiology ,Biopsy ,Cystic Fibrosis Transmembrane Conductance Regulator ,Fluorescent Antibody Technique ,Organic Anion Transporters ,Antiporters ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Lubiprostone ,Intestinal mucosa ,Intestinal Mucosa ,biology ,Sodium-Hydrogen Exchanger 3 ,Gastroenterology ,RNA-Binding Proteins ,Receptors, Prostaglandin E, EP1 Subtype ,Cystic fibrosis transmembrane conductance regulator ,Cell biology ,Sulfate Transporters ,Chloride channel ,Sodium-Potassium-Exchanging ATPase ,medicine.drug ,Muscle Contraction ,medicine.medical_specialty ,Sodium-Hydrogen Exchangers ,Sodium-Potassium-Chloride Symporters ,In Vitro Techniques ,Exocytosis ,Internal medicine ,medicine ,Animals ,Humans ,Alprostadil ,Ion transporter ,Analysis of Variance ,Ion Transport ,Activator (genetics) ,Sodium-Bicarbonate Symporters ,Prostanoid ,Membrane Transport Proteins ,Muscle, Smooth ,Cyclic AMP-Dependent Protein Kinases ,Rats ,CLC-2 Chloride Channels ,Mucus ,Endocrinology ,chemistry ,biology.protein ,Receptors, Prostaglandin E, EP4 Subtype - Abstract
Lubiprostone is a chloride channel activator in clinical use for the treatment of chronic constipation, but the mechanisms of action of the drug are poorly understood. The aim of this study was to determine whether lubiprostone exerts secretory effects in the intestine by membrane trafficking of ion transporters and associated machinery.Immunolabeling and quantitative fluorescence intensity were used to examine lubiprostone-induced trafficking of the cystic fibrosis transmembrane conductance regulator (CFTR), sodium/potassium-coupled chloride co-transporter 1 (NKCC1), electrogenic sodium/bicarbonate co-transporter 1 (NBCe1), down-regulated in adenoma (DRA), putative anion transporter 1 (PAT1), sodium/proton exchanger 3 (NHE3), Ca(2+) activated chloride channel 2 (ClC-2) serotonin and its transporter SERT, E prostanoid receptors EP4 and EP1, sodium/potassium ATPase (Na-K-ATPase) and protein kinase A (PKA). The effects of lubiprostone on mucus exocytosis in rat intestine and human rectosigmoid explants were also examined.Lubiprostone induced contraction of villi and proximal colonic plicae and membrane trafficking of transporters that was more pronounced in villus/surface cells compared to the crypt. Membrane trafficking was determined by: (1) increased membrane labeling for CFTR, PAT1, NKCC1, and NBCe1 and decreased membrane labeling for NHE3, DRA and ClC-2; (2) increased serotonin, SERT, EP4, EP1 and PKA labeling in enterochromaffin cells; (3) increased SERT, EP4, EP1, PKA and Na-K-ATPase in enterocytes; and (4) increased mucus exocytosis in goblet cells.These data suggest that lubiprostone can target serotonergic, EP4/PKA and EP1 signaling in surface/villus regions; stimulate membrane trafficking of CFTR/NBCe1/NKCC1 in villus epithelia and PAT1/NBCe1/NKCC1 in colonic surface epithelia; suppress NHE3/DRA trafficking and fluid absorption; and enhance mucus-mobilization and mucosal contractility.
- Published
- 2012
30. Aromatase- (estrogen synthetase) immunoreactive neurons in the rat septal area. A light and electron microscopic study
- Author
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Robert L. Jakab, Frederick Naftolin, and Nobuhiro Harada
- Subjects
Male ,medicine.medical_specialty ,medicine.drug_class ,Immunocytochemistry ,Central nervous system ,Population ,Rats, Sprague-Dawley ,Aromatase ,Terminology as Topic ,Internal medicine ,medicine ,Animals ,education ,Molecular Biology ,Neurons ,Microscopy ,education.field_of_study ,biology ,General Neuroscience ,Immunohistochemistry ,Rats ,Microscopy, Electron ,Stria terminalis ,Endocrinology ,medicine.anatomical_structure ,nervous system ,Estrogen ,biology.protein ,Female ,Septal Nuclei ,Neurology (clinical) ,Neuron ,Nucleus ,Developmental Biology - Abstract
The aromatase enzyme (estrogen synthetase) catalyzes the conversion of testosterone to estrogen in peripheral and central nervous tissue. Light and electron microscopic immunocytochemistry was used to study the localization of this enzyme in the septal area of adult male and female albino rats. Aromatase-immunoreactivity was found restricted to neuronal somata and dendritic arbors, and no sex differences were detected in its distribution or intensity. Most aromatase-immunoreactive neurons formed two oblique bands in the lateral and the medial zones of the lateral septum; in addition, labeled cells were present in the septohippocampal nucleus and the laterodorsal portion of the bed nucleus of the stria terminalis. Electron microscopy revealed that the majority of aromatase-positive neurons in the lateral septum exhibit somatic spines, a characteristic marker of a neuron population that is known to contribute to local and extraseptal projections. The presence of aromatase in lateral septal somatospiny neurons suggests that estrogen formed by these neurons may be critically involved in the septal control of steroid-dependent behaviors.
- Published
- 1994
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31. Aromatase immunoreactivity in the rat brain: Gonadectomy-sensitive hypothalamic neurons and an unresponsive 'limbic ring' of the lateral septum-bed nucleus-amygdala complex
- Author
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Frederick Naftolin, Csaba Leranth, Nobuhiro Harada, Robert L. Jakab, and Tamas L. Horvath
- Subjects
Male ,medicine.medical_specialty ,Ovariectomy ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Biology ,Biochemistry ,Amygdala ,Rats, Sprague-Dawley ,Aromatase ,Endocrinology ,Internal medicine ,Limbic System ,medicine ,Animals ,Molecular Biology ,Neurons ,Ventral striatum ,Brain ,Cell Biology ,Immunohistochemistry ,Axons ,Rats ,Stria terminalis ,medicine.anatomical_structure ,nervous system ,Organ Specificity ,Hypothalamus ,biology.protein ,Molecular Medicine ,Zona incerta ,Female ,Neuron ,Orchiectomy ,Nucleus - Abstract
The aromatase (estrogen synthetase) enzyme catalyzes the conversion of androgens to estrogens in peripheral tissues, as well as in the brain. Our study aimed at comparing the brain distribution of aromatase-immunoreactive neurons in male and female, normal and gonadectomized rats. Light microscopic immunostaining was employed using a purified polyclonal antiserum raised against human placental aromatase. Two anatomically separate aromatase-immunoreactive neuronal systems were detected in the rat brain: A “limbic telencephalic” aromatase system was composed by a large population of labeled neurons in the lateral septal area, and by a continuous “ring” of neurons of the laterodorsal division of the bed nucleus of stria terminalis, central amygdaloid nucleus, stria terminalis, and the substantia inominata-ventral pallidum-fundus striati region. The other, “hypothalamic” aromatase system consisted of neurons scattered in a dorsolateral hypothalamic area including the paraventricular, lateral and dorsomedial hypothalamic nuclei, the subincertal nucleus as well as the zona incerta. In addition, a few axon-like processes (unresponsive to gonadectomy) were present in the preoptic-anterior hypothalamic complex, the ventral striatum, and midline thalamic regions. No sexual dimorphism was observed in the distribution or intensity of aromatase-immunostaining. However, 3 days, 2, 3, 8, 16, or 32 weeks after gonadectomy, aromatase-immunoreactive neurons disappeared from the hypothalamus, whereas they were still present in the limbic areas of both sexes. The results indicate the existence of two distinct estrogen-producing neuron systems in the rat brain: (1) a “limbic ring” of aromatase-labeled neurons of the lateral septum-bed nucleus-amygdala complex unresponsive to gonadectomy; and (2) a sex hormone-sensitive “hypothalamic” aromatase neuron system.
- Published
- 1993
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32. Serum α2-HS glycoprotein concentration in patients with hematological malignancies
- Author
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L. Kalabay, K. Cseh, S. Benedek, S. Fekete, T. Masszi, K. Herjeczki, T. Pozsonyi, and L. Jakab
- Subjects
Adult ,Lung Diseases ,medicine.medical_specialty ,Adolescent ,Lymphoma ,alpha-2-HS-Glycoprotein ,Chronic lymphocytic leukemia ,Infections ,Polycythemia vera ,Male Urogenital Diseases ,hemic and lymphatic diseases ,Internal medicine ,medicine ,Humans ,Myelofibrosis ,Multiple myeloma ,Aged ,Aged, 80 and over ,Leukemia ,Hematology ,medicine.diagnostic_test ,business.industry ,Blood Proteins ,Organ Size ,General Medicine ,Middle Aged ,medicine.disease ,Female Urogenital Diseases ,Endocrinology ,Liver ,Primary Myelofibrosis ,Erythrocyte sedimentation rate ,Alkaline phosphatase ,Multiple Myeloma ,business ,alpha-2-HS-glycoprotein ,Spleen ,Follow-Up Studies - Abstract
We observed significantly reduced serum alpha 2-HS glycoprotein concentrations in patients with acute lymphocytic, acute nonlymphocytic, chronic granulocytic and chronic myelomonocytic leukemias, Hodgkin's and non-Hodgkin's lymphomas, myelofibrosis, and multiple myeloma, but not in patients with chronic lymphocytic leukemia and polycythemia vera, as compared with healthy controls. We followed the serum level of the protein for 18 months. Patients with infectious complications, those receiving cytostatic treatment, and those in the preterminal period had further reduced serum alpha 2-HS glycoprotein levels. The reduction of serum alpha 2-HS glycoprotein concentration was primarily due to decreased production caused by infiltration of the liver, a hepatotoxic effect of cytostatic treatment, and, to a lesser degree, to increased consumption. We found statistically significant negative correlations between serum alpha 2-HS glycoprotein concentration and erythrocyte sedimentation rate, serum aspartate aminotransferase and alkaline phosphatase activities, and IgG and IgM concentrations. The determination of the alpha 2-HS glycoprotein concentration is useful for the assessment and follow-up of the clinical status and therapy of patients with hematological malignancies and also has prognostic significance.
- Published
- 1991
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33. Convergent vasopressinergic and hippocampal input onto somatospiny neurons of the rat lateral septal area
- Author
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Frederick Naftolin, C. Leranth, and Robert L. Jakab
- Subjects
Male ,Dendritic spine ,Vasopressins ,Hippocampus ,Neuropeptide ,Biology ,Hippocampal formation ,Nerve Fibers ,medicine ,Animals ,Axon ,Neurons ,General Neuroscience ,Rats, Inbred Strains ,Long-term potentiation ,Anatomy ,Immunohistochemistry ,Rats ,Microscopy, Electron ,medicine.anatomical_structure ,nervous system ,Excitatory postsynaptic potential ,Septum Pellucidum ,Soma ,Neuroscience - Abstract
Electron microscopic immunocytochemistry was combined with acute anterograde axon degeneration, following transection of the fimbria-fornix, to describe the innervation of somatospiny neurons by vasopressin-immunoreactive and degenerated hippocamposeptal axon terminals in the rat lateral septal area. Vasopressin-immunopositive boutons characterized by symmetric synaptic membrane specializations, and the degenerated hippocamposeptal axon terminals which form asymmetric synaptic contacts, frequently terminate on the same dendritic and somatic profiles, and particularly on the somata of somatospiny neurons. Although hippocamposeptal fibers predominantly form axospinous synapses in the lateral septal area, they terminate mainly on the dendritic shafts and soma of the vasopressin-receptive neurons. Of 720 vasopressin-immunoreactive terminals in the mediolateral part of the lateral septal area, 80% form synaptic contacts with dendritic shafts: 50% on small (distal) dendritic profiles and 30% on large (proximal) dendrites. Synaptic contacts between vasopressin-immunoreactive terminals and dendritic spines were not observed. The remaining 20% of immunoreactive boutons formed axosomatic synaptic contacts with a total of 58 neurons; 31% of these neurons exhibited somatic spines in the plane of the section analysed. Previous studies have demonstrated that in the lateral septal area vasopressin modulates the action of the excitatory amino acid-containing hippocamposeptal fibers, and also plays a role in the maintenance of long term potentiation evoked by fimbria-fornix stimulation. The convergent vasopressinergic and hippocampal input onto the same somatospiny neurons of the lateral septal area suggests that these neurons are targets of these physiological actions.
- Published
- 1991
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34. Broadband One-port Material Characterization Method of Porous and Fluidic Materials
- Author
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L. Jakab, F. Lenart, and G. Karolyi
- Subjects
Permittivity ,Materials science ,Acoustics ,Broadband ,Electronic engineering ,Fluidics ,Coaxial ,Material properties ,Network analyzer (electrical) ,Porous medium ,Relative permeability - Abstract
Magnetic and electrical properties of materials are investigated by the use of a novel method inspired by the known distance-to-fault (DTF) measurement. The principles of the one-port method are detailed and it is verified by presenting measurement results. The complex relative permeability and permittivity of the samples are derived simultaneously by means of a network analyzer and control software. The coaxial sample holder designed for this measurement allows the investigation of liquid and porous materials. As a special feature, the method can be easily implemented into various applications, since it is based on using a scalar network analyzer. Precognition of the sample length is not necessary, which provides high level of flexibility when using the presented method.
- Published
- 2008
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35. Measurement of Complex Electromagnetic Properties of Ferrite Powders and Fluids
- Author
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L. Jakab, G. Karolyi, and F. Lenart
- Subjects
Permittivity ,Nuclear magnetic resonance ,Materials science ,Ferrite (magnet) ,Magnetic nanoparticles ,Nanoparticle ,Composite material ,Coaxial ,Material properties ,Relative permeability ,Porous medium - Abstract
Magnetic and electrical properties of ferrite powders are investigated by the use of a novel method, called Complex Material Properties from Scalar data (CMPS). The principles of the one-port method are detailed and they are verified by presenting measurement results. The complex relative permeability and permittivity of the samples are derived simultaneously by means of a network analyzer and control software. The coaxial sample holder designed for this measurement allows the investigation of liquid and porous materials. The presented method is supplemented by direct loss measurements at a single frequency in order to gain deeper knowledge of the investigated magnetic nanopowders.
- Published
- 2008
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36. The Peenemünde Wind Tunnels: A Memoir by Peter P. Wegener
- Author
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Peter L. Jakab
- Subjects
History ,Engineering (miscellaneous) - Published
- 1998
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37. Development of the Telecoms Power Systems in Hungary
- Author
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L. Jakab
- Subjects
Communication industry ,Electric power system ,Engineering ,business.industry ,Power engineering ,Switched-mode power supply applications ,Telecommunications ,business - Published
- 2005
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38. Computer based evaluation of battery capacity tests
- Author
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L. Jakab
- Subjects
Battery (electricity) ,Engineering ,Automatic test equipment ,Series (mathematics) ,business.industry ,Process (computing) ,Electronic engineering ,Effective method ,State (computer science) ,business ,Software measurement ,Voltage ,Reliability engineering - Abstract
The fully charged state and the ageing process of stationary batteries cannot be followed easily. The most effective method is the capacity test, which gives an exact result about the condition of battery cells. However, these results can depend on people who do the measuring. The evaluation of several different discharge processes are very hard because of the large amount of data. This paper introduces a computer-aided battery capacity test evaluation procedure which gives well ordered data sheets, shows the selected values in diagrams, calculates the partial and final results in the same way, so the results of different measuring series will be comparable. The program is able to compare the results of annual capacity tests and gives a good view about the expectable future behavior trend of the examined batteries. >
- Published
- 2005
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39. Using the BCH construction to generate robust linear hash functions
- Author
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J.P. Grossman and L. Jakab
- Subjects
Collision resistance ,Fowler–Noll–Vo hash function ,Theoretical computer science ,Computer science ,Hash function ,Cryptographic hash function ,SWIFFT ,Hash filter ,Rolling hash ,Algorithm ,Double hashing - Abstract
Providing a single hash function for use across multiple applications is challenging due to the fact that different applications require different sizes of hashed values. An application-independent hash function must be robust in the sense that it must maintain good characteristics independent of the number of output bits which are used. In this paper we show how the BCH construction can be used to construct a single n/spl rarr/m bit linear hash function with the property that that the n/spl rarr/m' bit subhash functions obtained by discarding the upper m - m' output bits all have provably good collision avoidance properties. We apply this technique to the construction of a 256/spl rarr/128 bit hash function. We find that of the 256/spl rarr/m' subhashes, over 78% have optimal minimum collision distances and all but one have a minimum collision distance within 2 of optimal.
- Published
- 2005
- Full Text
- View/download PDF
40. Glutamate N-methyl-D-aspartate and dopamine receptors have contrasting effects on the limbic versus the somatosensory cortex with respect to amphetamine-induced neurodegeneration
- Author
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Robert L. Jakab, John F. Bowyer, and Robert R. Delongchamp
- Subjects
Male ,medicine.medical_specialty ,Dopamine Agents ,Receptors, N-Methyl-D-Aspartate ,Receptors, Dopamine ,Rats, Sprague-Dawley ,Eticlopride ,Dopamine ,Piriform cortex ,Internal medicine ,Cortex (anatomy) ,Dopamine receptor D2 ,medicine ,Limbic System ,Animals ,Amphetamine ,Molecular Biology ,Chemistry ,General Neuroscience ,Somatosensory Cortex ,Rats ,Dizocilpine ,Endocrinology ,medicine.anatomical_structure ,Neuroprotective Agents ,nervous system ,Dopamine receptor ,Nerve Degeneration ,Neurology (clinical) ,Dizocilpine Maleate ,Neuroscience ,Excitatory Amino Acid Antagonists ,Developmental Biology ,medicine.drug - Abstract
The roles that glutamate N-methyl- d -aspartate (NMDA) and dopamine D1-like and D2-like receptors play in the cortical neurotoxicity occurring in rats exposed to multiple doses of amphetamine (AMPH) for 2 days was evaluated. Neurodegeneration in rats that did not become hyperthermic during AMPH exposure was quantified by counting isolectin B4-labeled phagocytic microglia and Fluoro-Jade (F-J)-labeled neurons in the somatosensory parietal cortex, piriform cortex and posterolateral cortical amygdaloid nucleus (PLCo). The NMDA receptor antagonist, dizocilpine (0.63 mg/kg day) blocked AMPH-induced neurodegeneration in the somatosensory cortex. However, it did not affect degeneration in the piriform cortex and PLCo indicating that limbic degeneration was not NMDA-mediated. The dopamine antagonists, eticlopride (D2/3, 0.25 mg/kg day) and SCH-23390 (D1, 0.25 mg/kg day), blocked the stereotypic behavior and neurodegeneration in the somatosensory cortex. However, eticlopride had a lesser protective effect in the limbic regions. As well, the dopamine D2/D3 agonist quinpirole (1.5 mg/kg day) protected against cortical neurodegeneration when it was given during AMPH exposure and continued until sacrifice. The dopamine D1 agonist (SKF-38393, 12.5 mg/kg day) had no significant effect on neurodegeneration. These data indicate that there are significant differences in NMDA and dopamine D2 modulation of AMPH-induced neurodegeneration in the somatosensory cortex compared to the limbic cortices, and limbic cortical degeneration is not necessarily dependent on excessive stimulation of NMDA receptors as it is in the somatosensory cortex. Although excessive dopamine receptor stimulation during amphetamine exposure may trigger the neurodegenerative processes, continued D2 stimulation after AMPH exposure is neuroprotective in the cortex.
- Published
- 2004
41. [Vascular injuries in everyday practice]
- Author
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B, Galambos, L, Tamás, P, Zsoldos, T, Czigány, L, Jakab, J, Németh, and L, Csönge
- Subjects
Adult ,Male ,Reoperation ,Adolescent ,Thoracic Injuries ,Wounds, Penetrating ,Wounds, Nonpenetrating ,Amputation, Surgical ,Veins ,Neck Injuries ,Blood Vessel Prosthesis Implantation ,Arteriovenous Shunt, Surgical ,Thoracic Arteries ,Humans ,Child ,Polytetrafluoroethylene ,Aged ,Retrospective Studies ,Aged, 80 and over ,Arm Injuries ,Hungary ,Leg ,Multiple Trauma ,Polyethylene Terephthalates ,Anastomosis, Surgical ,Angiography ,Graft Occlusion, Vascular ,Arteries ,Middle Aged ,Limb Salvage ,Arteriovenous Fistula ,Arm ,Female ,Aneurysm, False ,Follow-Up Studies ,Leg Injuries - Abstract
It was the objective of this retrospective study to analyse the causes of injury, surgical approaches, outcome, and complications in patients with vascular trauma and to report our experience with vein homografts for arterial reconstruction in the upper and lower limbs and cervicothoracic region in patients operated on over a period between 1981-2001.In 128 patients with peripheral arterial injuries the mechanism was direct penetration in 90 cases and blunt injury in 20 cases. In 4 cases a chronic damage (false aneurysm, AV fistula) was observed. Isolated vascular trauma was present in 97 patients (75.8%), 31 cases (24.2%) were aggravated by concomitant bone fractures, and nerve or soft tissue damage. Most frequently injured vessels were the superficial femoral (22.6%), crural (22.6%), and ulnar and radial (13.2%) arteries. 16 patients with penetrating cervicothoracic arterial injuries were registered during this period. 8 patients underwent emergency exploration and 8 patients angiography prior urgent exploration.Saphenous vein interposition grafting was applied with good results in 34 patients, polytetrafluoroethylene and Dacron grafts were used in eight cases, end to end anastomosis in 12 cases, venous bypasses in 5 cases, venous patches in 7 cases. 17 patients underwent arterial repair and 9 venous repair. Vein homografts as an arterial substitute were implanted in 8 patients. Five secondary amputations were performed and five patients died. The limb salvage rate was 95% and the primary patency rate of vein homografts was 75% (excluded primary amputations). The penetrating cervicothoracic injuries were all repaired with improvement in level of consciousness and neurological deficit when present.Most vascular injuries of the extremities can be managed successfully unless associated with severe concomitant damage of the bones, nerves and soft tissues. In the absence of suitable autologous vein grafts, homografts appear to be an interesting alternative for arterial repair. In penetrating cervicothoracic vascular injuries immediate operative repair offers the best chance of recovery.
- Published
- 2004
42. Selective changes in gene expression in cortical regions sensitive to amphetamine during the neurodegenerative process
- Author
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Diane B. Miller, Angela J. Harris, A.Roger Little, Robert R. Delongchamp, John F. Bowyer, Robert L. Jakab, and James P. O'Callaghan
- Subjects
Male ,medicine.medical_specialty ,Dopamine ,Substantia nigra ,Striatum ,Toxicology ,Rats, Sprague-Dawley ,Dopamine receptor D2 ,Internal medicine ,Gene expression ,medicine ,Animals ,Amphetamine ,Dopamine transporter ,Oligonucleotide Array Sequence Analysis ,Cerebral Cortex ,biology ,General Neuroscience ,Neurotoxicity ,Neurodegenerative Diseases ,medicine.disease ,Rats ,Endocrinology ,Gene Expression Regulation ,biology.protein ,medicine.drug - Abstract
Gene expression profiles in several brain regions of adult male rats were evaluated following a d -amphetamine (AMPH) exposure paradigm previously established to produce AMPH neurotoxicity. Escalating doses of AMPH (5–30 mg/kg) were given over the course of 16 h per day in an 18 °C environment for 2 days. This paradigm produces neurotoxicity but eliminates or minimizes the hyperthermia and seizure activity that might influence gene expression in a manner unrelated to the neurotoxic effects of AMPH. The expression of 1185 genes was monitored in the striatum, parietal cortex, piriform cortex and posteriolateral cortical amygdaloid nucleus (PLCo) using cDNA array technology, and potentially significant changes were verified by RT–PCR. Gene expression was determined at time points after AMPH when neurodegeneration was beginning to appear (16 h) or maximal (64 h). Expression was also determined 14 days after AMPH to find long-term changes in gene expression that might be biomarkers of a neurotoxic event. In the parietal cortex there was a two-fold increase in neuropeptide Y precursor protein mRNA whereas nerve growth factor-induced receptor protein I-A and I-B mRNA decreased 50% at 16 h after the end of AMPH exposure. Although these changes in expression were not observed in the PLCo, insulin-like growth factor binding protein 1 mRNA was increased two-fold in the PLCo at 16 and 64 h after AMPH. Changes in gene expression in the cortical regions were all between 1.2- and 1.5-fold 14 days after AMPH but some of these changes, such as annexin V increases, may be relevant to neurotoxicity. Gene expression was not affected by more than 1.5-fold at the time points in the striatum, although 65% dopamine depletions occurred, but the plasma membrane-associated dopamine transporter and dopamine D2 receptor were decreased about 40% in the substantia nigra at 64 h and 14 days post-AMPH. Thus, the 2-day AMPH treatment produced a few changes in gene expression in the two-fold range at time points 16 h or more after exposure but the majority of expression changes were less than 1.5-fold of control. Nonetheless, some of these lesser fold-changes appeared to be relevant to the neurotoxic process.
- Published
- 2003
43. Parvalbumin neuron circuits and microglia in three dopamine-poor cortical regions remain sensitive to amphetamine exposure in the absence of hyperthermia, seizure and stroke
- Author
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John F. Bowyer and Robert L. Jakab
- Subjects
Male ,medicine.medical_specialty ,Fever ,Tyrosine 3-Monooxygenase ,Dopamine ,Striatum ,Rats, Sprague-Dawley ,Interneurons ,Seizures ,Piriform cortex ,Internal medicine ,Glial Fibrillary Acidic Protein ,medicine ,Animals ,Gliosis ,Molecular Biology ,Cerebral Cortex ,biology ,Chemistry ,General Neuroscience ,Barrel cortex ,medicine.disease ,Immunohistochemistry ,Drug Residues ,Astrogliosis ,Rats ,Stroke ,Amphetamine ,medicine.anatomical_structure ,Endocrinology ,Parvalbumins ,nervous system ,Cerebral cortex ,Astrocytes ,Nerve Degeneration ,biology.protein ,Neurology (clinical) ,Neuron ,Microglia ,Neuroscience ,Parvalbumin ,Developmental Biology ,medicine.drug - Abstract
The dopamine-releasing and depleting substance amphetamine (AMPH) can make cortical neurons susceptible to damage, and the prevention of hyperthermia, seizures and stroke is thought to block these effects. Here we report a 2-day AMPH treatment paradigm which affected only interneurons in three cortical regions with average or below-average dopamine input. AMPH (six escalating doses/day ranging from 5 to 30 mg/kg for 2 days) was given at 17-18 degrees C ambient temperature (T) to adult male rats. During the 2-day AMPH treatment, peak body T stayed below 38.9 degrees C in 40% of the AMPH treated rats. In 60% of the rats, deliberate cooling suppressed (
- Published
- 2002
44. Dimensioning aspects of 48 V telecommunications power supply systems
- Author
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L. Jakab
- Subjects
Presentation ,Engineering ,business.industry ,media_common.quotation_subject ,Emphasis (telecommunications) ,Electric fuses ,business ,Telecommunications ,Dimensioning ,Voltage ,media_common ,Power (physics) - Abstract
Considering the reliable operation of 48 V telecommunications power supply systems, it is essential for appropriate dimensioning. The basic elements of the power supply systems, i.e. batteries, rectifiers, DC/AC cabling, fuses, etc., should be defined by exact calculation. The presentation reviews the main questions and problems of dimensioning. It lays a special emphasis on the optimized planning procedure, further it also deals with the economical impacts of the dimensioning parameters.
- Published
- 2002
- Full Text
- View/download PDF
45. [Further data on the subject of endothelial dysfunction]
- Author
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L, Jakab
- Subjects
Vasculitis ,Transforming Growth Factor beta ,Terminology as Topic ,Chronic Disease ,Selectins ,Humans ,Endothelium, Vascular - Published
- 2002
46. High levels of antibodies against Clq are associated with disease activity and nephritis but not with other organ manifestations in SLE patients
- Author
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L, Horváth, L, Czirják, B, Fekete, L, Jakab, T, Pozsonyi, L, Kalabay, L, Romics, K, Miklós, L, Varga, Z, Prohászka, A, Szakács, E, Nagy, M R, Daha, and G, Füst
- Subjects
Adult ,Male ,alpha-2-HS-Glycoprotein ,Antibodies, Antinuclear ,Complement C1q ,Age Factors ,Humans ,Enzyme-Linked Immunosorbent Assay ,Female ,Blood Proteins ,Complement C3 ,Lupus Nephritis - Abstract
Serum concentration of antibodies to C1q (C1qAb) has been reported to be elevated in a high percentage of patients with systemic lupus erythematosus (SLE). The associations of high C1qAb levels with different clinical manifestations and the activity of the disease, however, are not definitely understood.We measured the levels of IgG type C1qAb in the sera of 137 patients with SLE using an ELISA method.Serum concentrations of C1qAb were found to be higher (p0.0001) in SLE patients than in healthy controls. High titer (66 AU/ml) C1qAb was found in 40/137 (29.2%) SLE patients, and 4/192 (2.1%) healthy controls (p0.0001). A strong negative correlation (R = -0.4, p0.0001) between the age of the patients and the C1qAb titers could be detected. C1qAb levels in clinically active SLE patients significantly (p0.0001) exceeded those measured in the sera of patients in the inactive stage of the disease. A significant positive correlation was detected between C1qAb levels and the laboratory activity markers (anti-DNA, low C3 level) of the disease. We found a significant negative correlation between levels of C1qAb and a negative acute phase protein, alpha2-HS-glycoprotein. Renal involvement was present in 11/40 (27.5%) and 11/97 (11%) of the patients with high and low titers of C1qAb, respectively (p = 0.038). The prevalence of other organ manifestations was, however, the same in the patients with or without high titer C1qAb.These findings indicate that C1qAb measurement is a useful method for detecting the activity of SLE and predicting renal manifestations, but not other organ involvement in the disease.
- Published
- 2002
47. Mo1752 Linaclotide Induces Endocytosis of the Sodium/Hydrogen Exchanger 3 (NHE3) and Inhibits Sodium Absorption
- Author
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Robert L. Jakab, Inmaculada Silos-Santiago, Boris Tchernychev, Gerhard Hannig, David Arthur, and Nadia A. Ameen
- Subjects
Sodium–hydrogen antiporter ,chemistry.chemical_compound ,Hepatology ,Chemistry ,Sodium ,Inorganic chemistry ,Gastroenterology ,chemistry.chemical_element ,Endocytosis ,Absorption (electromagnetic radiation) ,Linaclotide - Published
- 2014
- Full Text
- View/download PDF
48. [To the Editor: The problem of celiac disease in the present]
- Author
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L, Jakab
- Subjects
CD4-Positive T-Lymphocytes ,B-Lymphocytes ,Celiac Disease ,Antigens, CD ,Humans ,Lymphoma, B-Cell, Marginal Zone ,Immunoglobulin A - Published
- 2001
49. Muscarinic m1 and m2 receptor proteins in local circuit and projection neurons of the primate striatum: anatomical evidence for cholinergic modulation of glutamatergic prefronto-striatal pathways
- Author
-
Robert L. Jakab, Patricia S. Goldman-Rakic, Adriana A. Alcantara, Steven M. Hersch, Allan I. Levey, and Ladislav Mrzljak
- Subjects
Male ,Calbindins ,Glutamic Acid ,Prefrontal Cortex ,Striatum ,Neurotransmission ,Biology ,Medium spiny neuron ,Choline O-Acetyltransferase ,Glutamatergic ,S100 Calcium Binding Protein G ,Neural Pathways ,Muscarinic acetylcholine receptor M4 ,Animals ,Neurons ,Receptor, Muscarinic M2 ,General Neuroscience ,Receptor, Muscarinic M1 ,NADPH Dehydrogenase ,Muscarinic acetylcholine receptor M2 ,Choline acetyltransferase ,Macaca mulatta ,Receptors, Muscarinic ,Acetylcholine ,Corpus Striatum ,Microscopy, Electron ,Parvalbumins ,nervous system ,Cholinergic Fibers ,Synapses ,Acetylcholinesterase ,Cholinergic ,Female ,Neuroscience - Abstract
The cellular and subcellular localization of muscarinic receptor proteins m1 and m2 was examined in the neostriatum of macaque monkeys by using light and electron microscopic immunocytochemical techniques. Double-labeling immunocytochemistry revealed m1 receptors in calbindin-D28k–positive medium spiny projection neurons. Muscarinic m1 labeling was dramatically more intense in the striatal matrix compartment in juvenile monkeys but more intense in striosomes in the adult caudate, suggesting that m1 expression undergoes a developmental age-dependent change. Ultrastructurally, m1 receptors were predominantly localized in asymmetric synapse-forming spines, indicating that these spines receive extrastriatal excitatory afferents. The association of m1-positive spines with lesion-induced degenerating prefronto-striatal axon terminals demonstrated that these afferents originate in part from the prefrontal cortex. The synaptic localization of m1 in these spines indicates a role of m1 in the modulation of excitatory neurotransmission. To a lesser extent, m1 was present in symmetric synapses, where it may also modulate inhibitory neurotransmission originating from local striatal neurons or the substantia nigra. Conversely, m2/choline acetyltransferase (ChAT) double labeling revealed that m2-positive neurons corresponded to large aspiny cholinergic interneurons and ultrastructurally, that the majority of m2 labeled axons formed symmetric synapses. The remarkable segregation of the m1 and m2 receptor proteins to projection and local circuit neurons suggests a functional segregation of m1 and m2 mediated cholinergic actions in the striatum: m1 receptors modulate extrinsic glutamatergic and monoaminergic afferents and intrinsic GABAergic afferents onto projection neurons, whereas m2 receptors regulate acetylcholine release from axons of cholinergic interneurons. J. Comp. Neurol. 434:445–460, 2001. © 2001 Wiley-Liss, Inc.
- Published
- 2001
50. Estrogen receptor beta immunoreactivity in differentiating cells of the developing rat cerebellum
- Author
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R L, Jakab, J K, Wong, and S M, Belcher
- Subjects
Male ,Neurons ,Age Factors ,Cell Differentiation ,Immunohistochemistry ,Rats ,Rats, Sprague-Dawley ,Purkinje Cells ,Sex Factors ,Animals, Newborn ,Receptors, Estrogen ,Cerebellum ,Animals ,Estrogen Receptor beta ,Female - Abstract
Estrogen receptors (ER) play a significant role in the development of some regions of the mammalian brain. Recently, ER-beta (ERbeta) mRNA and protein were shown to be expressed in the rat cerebellum. In the present study, the ontogeny of ERbeta protein expression was examined in the rat cerebellum during postnatal development. Western blot analysis indicated that a single ERbeta-like immunoreactive species of approximately 55 kDa was present in protein lysates prepared from the cerebella of female and male Sprague-Dawley rat pups. Immunocytochemical analysis of cerebellar sections from the midline vermis revealed that during development, the expression of ERbeta varied with age and cell-type, but not sex. In the developing cerebellum, highest levels of ERbeta-immunoreactivity (IR) were detected in neurons during neurite growth, and in some glia during migration. Throughout the first postnatal week, ERbeta-IR was localized to differentiating granule cells in the external germinal layer and to migrating glia. Differentiating granule cells expressed detectable levels of ERbeta throughout development. In Purkinje cells, ERbeta-IR was first detected on postnatal day 6 (P6), with peak intensities of immunostaining coinciding with the initiation of axonal and dendritic growth that occurs between P7 and P8. Expression of ERbeta-IR remained high during maturation of Purkinje cell dendrites, and then decreased to a lower level maintained in the adult. From the third postnatal week, ERbeta-IR was also detected in the later developing Golgi, stellate, and basket neurons. These results suggest that ERbeta may play a role in growth-related mechanisms during differentiation of cerebellar neurons and glia.
- Published
- 2001
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