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Tissue engineered scaffolds are currently being explored to aid in healing and regeneration of non-union fractures in bone. Additionally, albumin has been demonstrated to provide benefits to healing when applied to injury sites. This paper focuses on delivery of calcium modified, bioactive bovine serum albumin (BSA) from a multi-functional polyampholyte polymer scaffold. First, the inherent nonfouling and conjugation properties of the polyampholyte hydrogel were verified to determine the impact of calcium exposure. The polyampholyte hydrogel delivery platform was then assessed with calcium titrations and osteoblast-like cell (MC3T3-E1) adhesion, proliferation, and viability evaluations. Finally, integrin inhibitors were used to identify the binding mechanisms that mediate cell adhesion to the calcium-modified BSA-conjugated hydrogels. An increase in cell adhesion was observed following calcium exposure up to 0.075 M, although this and higher calcium concentrations affected hydrogel stability and cell growth. BSA exposed to 0.05 M calcium and delivered from polyampholyte hydrogels promoted the most promising viable cell adhesion over 7 days. Cell adhesion to the calcium-modified BSA-conjugated hydrogels appeared to be regulated by arginine-glycine-aspartic acid (RGD) and collagen specific integrins. These results demonstrate that the delivery of calcium modified BSA from an implantable polymer scaffold is promising for bone tissue engineering applications.

Synthetic hydroxyapatite (HAp) bioceramics commonly serve as non-load bearing implants due to their bone-like composition. Additionally, the porous structure promotes tissue ingrowth and osseointegration. However, HAp bioceramics have insufficient mechanical properties and low bioactivity. This study aims to evaluate how substituted chloride levels in hydroxyapatite (ClHAP) affect the surface and mechanical properties, and osteoblastic response. ClHAP was made via an aqueous precipitation method followed by hydraulic compaction and sintering at 1100 °C for 16 h. This study demonstrated highly densified 2–10% ClHAP bioceramics with outstanding surface hardness and compressive strength, and enhanced surface wettability, relative to other HAp bioceramics. The 2–10% ClHAP bioceramics showed slight acidity and chloride release in vitro, which did not significantly affect the osteoblast adhesion or proliferation. In conclusion, 2–10% ClHAP bioceramics are optimal for implantation for their superior surface and mechanical properties, biocompatibility, and potential for long-term osseointegration.

Polyampholyte hydrogels are attractive materials for tissue engineering scaffolds as they offer a wide variety of features including nonfouling, selective protein delivery, and tunable physical characteristics. However, to improve the potential performance of these materials for in vivo applications, there is a need for a higher diversity of zwitterionic cross-linker species to replace commonly used ethylene glycol (EG) based chemistries. Towards this end, the synthesis of a dipeptide based zwitterionic cross-linker, N-Ser-Ser-C dimethacrylate (S-S) from N-Boc-l-serine is presented. The strategy utilized a convergent coupling of methacrylated serine partners followed by careful global deprotection to yield the zwitterionic cross-linker with good overall yields. This novel cross-linker was incorporated into a polyampholyte hydrogel and its physical properties and biocompatibility were compared against a polyampholyte hydrogel synthesized with an EG-based cross-linker. The S-S cross-linked hydrogel demonstrated excellent nonfouling performance, while promoting enhanced cellular adhesion to fibrinogen delivered from the hydrogel. Therefore, the results suggest that the S-S cross-linker will demonstrate superior future performance for in vivo applications.

Tissue-engineered scaffolds encounter many challenges including poor integration with native tissue. Nonspecific protein adsorption can trigger the foreign body response leading to encapsulation and isolation from the native injured tissue. This concern is mitigated with nonfouling polymer scaffolds. This study investigates the long-term biocompatibility of a nonfouling polyampholyte system composed of positively charged [2-(acryloyloxy)ethyl]trimethylammonium chloride monomers and negatively charged 2-carboxyethyl acrylate monomers, cross-linked with triethylene glycol dimethacrylate. This system has previously shown resistance to nonspecific protein adsorption and short-term cell attachment via conjugated proteins. However, longer-term cell survival has not been evaluated with this system. First, the environmental pH was monitored with varying amounts of counter ions present in the hydrogel synthesis buffer. The lowest level (3 M NaOH) and the level that resulted in pH values closest to physiological conditions (6.7 M NaOH) were chosen for further investigation. These two formulations were then compared in terms of their contact angle, qualitative protein adsorption and conjugation capacity, and quantitative cell adhesion, proliferation, and viability. The 3 M NaOH formulation showed higher initial protein conjugation and cell adhesion compared to the 6.7 M NaOH formulation. However, the 3 M NaOH hydrogels had low cell viability after 24 h due to the acidic component release into the culture environment. The 6.7 M NaOH formulation showed a lower initial conjugation and cell adhesion but overcame this limitation by providing a stable environment that maintained cell viability for over 5 days. The 6.7 M NaOH polyampholyte hydrogel formulation shows increased biocompatibility, while maintaining resistance to nonspecific protein adsorption, as demonstrated by the targeted cell adhesion and proliferation. Therefore, this polyampholyte formulation demonstrates strong potential as a tissue-engineered scaffold.

The noradrenergic system shows pathological modifications in aging and neurodegenerative diseases and is thought to be affected in the early stages of both Alzheimer and Parkinson’ ss diseases. We conducted a meta-analysis of noradrenergic differences in Alzheimer’s disease type dementia (ADD) and Parkinson’s disease (PD) using CSF and PET biomarkers. CSF noradrenaline (NA) and 3-methoxy-4-hydroxyphenylglycol (MHPG) as well as NA transporter availability (PET MeNER) levels in controls, ADD and PD patients was summarized from 26 articles (1025 patients and 839 controls in total) using a random-effects model meta-analysis. Compared with controls, PD patients showed significant reductions in CSF NA and MHPG, and PET MeNER binding in the hypothalamus. In ADD, MHPG levels were increased compared with controls. Age correlated with CSF MHPG levels in ADD, but not in PD. Noradrenergic dysfunction in neurodegenerative diseases can be detected using CSF or PET measures and may be more pronounced in PD compared to ADD.

Background: The clinical impact and therapeutic implications of COVID-19 infection in a patient with pre-existing liver disease is unknown. We present a case of a middle-aged female with underlying non-alcoholic steatohepatitis associated cirrhosis who suffered a fatal pulmonary hemorrhage associated with COVID-19 infection. While the management of COVID-19 is evolving with regards to therapeutic anticoagulation requirements in critically ill patients, the impact of a pre-existing liver disease and its therapeutic implications when associated with COVID-19 is yet to be thoroughly elucidated. Case Report: Our patient is a 47 year old female with a past medical history of hypertension, hypothyroidism, fibromyalgia, non-decompensated NASH cirrhosis Child-Pugh Class C, gastric bypass surgery who developed progressive shortness of breath secondary to a COVID-19 pneumonia requiring hospitalization. She then developed acute hypoxic respiratory failure that required mechanical ventilation for over two weeks. Dexamethasone and Convalescent plasma were given for treatment of COVID-19. Unfortunately, her respiratory status during her ICU stay, declined requiring interventions including neuromuscular blockers and proning for refractory hypoxemia. She concurrently developed acute kidney injury requiring continuous renal replacement therapy. Her hospital course was also complicated by septic shock requiring vasopressors secondary to candidemia, and she was initiated on antifungal therapy with fluconazole. During ongoing CRRT therapy, we encountered recurrent clotting events and with the presumed COVID related hypercoagulability, patient was initiated on anticoagulation with systemic unfractionated heparin protocol. On day 17, her respiratory status and shock had resolved. However, her clinical status deteriorated quickly with recurrent shock of presumed sepsis, requiring initiation of broad spectrum antibiotics including vancomycin and piperacillin-tazobactam. Over the course of these 24 hours, patient suffered a fatal pulmonary hemorrhage despite massive transfusion protocol and reversal with protamine sulfate. Conclusion: We presented a cirrhotic patient who died of massive pulmonary hemorrhage associated with COVID-19 infection. There is overall paucity in the literature and in our understanding of management of COVID-19 associated with liver disease. While the literature reports a higher incidence of venous thromboembolic disease in COVID-19 patients, there are several challenges encountered with initiation of anticoagulation in a cirrhotic patient with concurrent coagulopathy. There are however anecdotal reports of favorable outcomes reported in these patients with use of anticoagulation possibly secondary to their antifibrotic properties. Future studies are required to clarify the role of safe and effective anticoagulation, criteria to make this decision, and perhaps even the choice of anticoagulation in patients with underlying liver disease.

Serum albumin is the most prominent protein in blood, and it aids in bone fracture healing, though the manner through which enhanced healing occurs is not well understood. This study investigates the influence of calcium on the bioactivity of albumin due to the prevalence of calcium at bone injury sites. Bovine serum albumin (BSA) was exposed to varying concentrations of calcium, adsorbed to tissue culture polystyrene, and the subsequent BSA-coated surfaces were evaluated with calcium titration, and cell adhesion, viability, and binding inhibition studies. Calcium-modified BSA improved overall MC3T3-E1 osteoblast-like cell adhesion, although high calcium concentrations induced cell death. Inhibiting specific integrins revealed that without calcium exposure, cell binding to BSA was primarily mediated by integrins that typically bind to the GFOGER sequence of collagen. As calcium exposure increases, the primary binding interaction transitioned to integrins known to bind RGD. However, cell binding to calcium-modified BSA was not completely eliminated during the inhibition studies indicating additional unidentified binding interactions occur. Overall, these results suggest that the exposure to calcium induces conformational changes that affect the cell-binding bioactivity of BSA, which may explain the beneficial impact of albumin in bone tissue.

Vaping Syndromic Surveillance Increases in EVALI were identified in 2019. Using the National Syndromic Surveillance Program, which includes about 70% of U.S. EDs, researchers found a gradual increa...

Titanium (Ti) and its alloys (especially Ti-6Al-4V or Ti64) are commonly used as load-bearing implants because of their biocompatibility and resistance to fatigue and corrosion. However, Ti/alloys are bio-inert metals and not prone to osseointegration. In order to further improve the bioactivity and osseointegration of Ti64, this study evaluated the modification of the Ti64 surface with a deposited chlorine substituted hydroxyapatite (ClHAP)/polydopamine (Pda) composite coating. Pda serves as an adhesion molecule and ClHAP releases slight acidity that stimulates osteoclastic activity. The composite coating with 10-30 % ClHAP particles is shown to promote bioactivity as evidenced by osteoblast proliferation. Therefore, this coating approach may enhance osseointegration in vivo.

Polyampholytes are a class of polymers made up of positively and negatively charged monomer subunits. Polyampholytes offer a unique tunable set of properties driven by the interactions between the charged monomer subunits. Some tunable properties of polyampholytes include mechanical properties, nonfouling characteristics, swelling due to changes in pH or salt concentration, and drug delivery capability. These characteristics lend themselves to multiple biomedical applications, and this review paper will summarize applications of polyampholyte polymers demonstrated over the last five years in tissue engineering, cryopreservation and drug delivery.

Coccidioides spp. are saprophytic, dimorphic fungi that are endemic to arid climates, are capable of infecting many species, and result in diverse clinical presentations. An indoor-housed laboratory rhesus macaque presented with weight loss and decreased activity and appetite. During the diagnostic evaluation, a bronchiolar–alveolar pattern in the cranial lung lobes, consistent with bronchopneumonia, was noted on radiographs. Given the poor prognosis, the macaque was euthanized. Confirming the radiographic assessment, gross necropsy findings included multifocal to coalescing areas of consolidation in the right and left cranial lung lobes. Microscopically, the consolidated regions were consistent with a pyogranulomatous bronchopneumonia and contained round, nonbudding, fungal yeast structures considered to be morphologically consistent with Coccidioides immitis. Culture and colony morphology results were confirmed through additional diagnostic testing. Sequencing of the D1–D2 domain of the 28S large ribosomal subunit positively matched with a known sequence specific to C. immitis. Serology for Coccidioides spp. by both latex agglutination (IgM) and immunodiffusion (IgG) was positive. In this rhesus macaque, the concordant results from histology, culture, DNA sequencing, and serology were collectively used to confirm the diagnosis of coccidioidomycosis. This animal likely acquired a latent pulmonary infection with Coccidioides months prior to arrival, when housed outdoors in a Coccidioides-endemic area. The nonspecific clinical presentation in this macaque, coupled with the recent history of indoor housing and lag between clinical presentation and outdoor housing, can make similar diagnostic cases challenging and highlights the need for awareness regarding animal source when making an accurate diagnosis in an institutional laboratory setting.

Polymeric tissue engineering scaffolds have shown promise to aid in regeneration and repair of damaged tissue. In particular, nonfouling polymers have been proposed for eliminating biomaterial-induced concerns such as infection, scarring, and rejection by the immune system. Polyampholyte polymers are one class of nonfouling polymers that are composed of an equimolar mixture of positively and negatively charged monomer subunits. They possess nonfouling properties, bioactive molecule conjugation capabilities, and tunable mechanical properties. In this study, the influence of the cross-linker species on the degradation behavior, mechanical strength, and nonfouling properties of polyampholytes composed of a 1:1 molar ratio of [2-(acryloyloxy)ethyl] trimethylammonium chloride (positively charged) and 2-carboxyethyl acrylate (negatively charged) monomers was investigated. Specifically, the impact of ethylene glycol repeat units on the overall material performance was evaluated by synthesizing and characterizing hydrogels containing di-, tri-, and tetra-ethylene glycol dimethacrylate cross-linker species. The degradation studies were conducted for over 100 days in Sorenson's buffer with pH values of 4.5, 7.4, and 9.0 by tracking the swelling behavior and weight change over time. The mechanical properties were assessed using compression and tensile testing to failure. The retention of the nonfouling and protein conjugation capabilities was demonstrated using fluorescently labeled bovine serum albumin. The results demonstrate the tunability of both degradation behavior and mechanical properties through the cross-linker selection, without impacting the underlying nonfouling and biomolecule delivery capabilities. Therefore, it is concluded that polyampholyte hydrogels represent a promising platform for tissue engineering.

It is well-known that the initiation and propagation behaviour of small cracks is strongly influenced by the microstructure. In addition to the visible structure on the surface, in-depth information is essential for the evaluation of influencing factors. Investigations on micro-crack behaviour have been performed with intermetallic γ-based TiAl. Starter notches facilitate systematic studies as cracks initiate from notch tips. In this case artificial notches in the scale less than colony dimensions were prepared by femtosecond pulsed laser radiation, which causes no significant damage. After multistage tensile compression tests under increasing load, several small cracks were generated and analyzed in the SEM. Using femtosecond laser-induced breakdown spectroscopy (fs-LIBS) it was possible to analyze spectrochemically the surrounding microstructure of these micro-cracks and their propagation on the surface.

Therapies that suppress RIPK1 kinase activity are emerging as promising therapeutic agents for the treatment of multiple inflammatory disorders. The ability to directly measure drug binding of a RIPK1 inhibitor to its target is critical for providing insight into pharmacokinetics, pharmacodynamics, safety and clinical efficacy, especially for a first‐in‐class small‐molecule inhibitor where the mechanism has yet to be explored. Here, we report a novel method for measuring drug binding to RIPK1 protein in cells and tissues. This TEAR1 (Target Engagement Assessment for RIPK 1) assay is a pair of immunoassays developed on the principle of competition, whereby a first molecule (ie, drug) prevents the binding of a second molecule (ie, antibody) to the target protein. Using the TEAR1 assay, we have validated the direct binding of specific RIPK1 inhibitors in cells, blood and tissues following treatment with benzoxazepinone (BOAz) RIPK1 inhibitors. The TEAR1 assay is a valuable tool for facilitating the clinical development of the lead RIPK1 clinical candidate compound, GSK2982772, as a first‐in‐class RIPK1 inhibitor for the treatment of inflammatory disease.

Laser material processing of dielectrics with temporally asymmetric femtosecond laser pulses of identical fluence, spectrum, and statistical pulse duration is investigated experimentally. To that end single shot structures at the surface of fused silica as a function of fluence and pulse shape are analyzed with the help of scanning electron microscopy. Structures for the bandwidth limited pulses show the known expansion in structure size with increasing laser fluence approaching the diffraction limit, which is 1.4 μm for the 0.5NA microscope objective used. In contrast, structures from the asymmetric pulses are remarkably stable with respect to variations in laser fluence and stay below 300 nm despite doubling the fluence. Different thresholds for surface material modification with respect to an asymmetric pulse and its time reversed counterpart are attributed to control of different ionization processes.

Since small crack propagation behavior is strongly affected by microstructure, very small artificial notches with a length in the submillimeter range are needed for a systematic study of microcrack behavior. Laser processing technique with ultrashort pulses is a micromachining tool which will not cause any serious mechanical damage in metallic materials. Small artificial starter notches were manufactured in medium carbon steels with this technique and some fatigue tests were carried out. Laser affected zones could be observed at the notch boundary but cracks were initiated from the notch tips and propagated steadily. The crack paths were very tortuous like natural small cracks. The experimental results showed that the femtosecond laser processing technique is useful to introduce a small notch and allows systematic investigation of microcrack behavior.

PURPOSE To evaluate the genetic contribution in age-related macular degeneration (ARMD) by a disease-ascertained twin study. METHODS Concordance rates for ARMD in 25 twins were obtained by using four masked graders to confirm the diagnosis of ARMD and place subjects in one of three categories; concordant, intermediate, or discordant. Demographic features and known risk factors for ARMD were compared between monozygotic and dizygotic twin pairs. RESULTS Of the 25 twin pairs, 15 were monzygotic and 10 were dizygotic. All 15 monozygotic twins were concordant or intermediate for ARMD. Of the dizygotic twin pairs, only one was concordant and five were discordant. In the demographic and risk factor analysis no unusual contributing or confounding variables were detected. CONCLUSIONS The association between zygosity and concordance for ARMD suggests a major importance for genetics in the etiology of ARMD. Our data further support a multi-factorial, primarily polygenic etiology for the condition.

Ritodrine- and terbutaline-induced hypokalemia in preterm labor: Mechanisms and consequences. The effects of ritodrine and terbutaline on potassium homeostasis, renal function, and cardiac rhythm were assessed in women treated with these drugs for preterm labor. Timed blood and urine samples were obtained for two hours before and during six hours of intravenous ritodrine (N = 5) and terbutaline (N = 5) administered in pharmacologically equivalent doses. No differences were found in any parameters affecting potassium homeostasis or renal function between these drugs. A decrease in mean plasma potassium of 0.9 mEq/liter occurred after 30 minutes of drug infusion (4.2 ± 0.1 to 3.3 ± 0.1 mEq/liter, P < 0.005) before any significant changes in plasma glucose (75.0 ± 4.7 to 93.7 ± 6.1 mg/dl, P = NS) or plasma insulin (12.4 ± 6.0 to 28.4 ±5.1 mU/ml, P = NS). The mean plasma potassium after four hours of drug infusion was 2.5 ±0.1 mEq/liter. Plasma insulin rose to a level known to induce cellular potassium uptake (39.2 ±7.7 mU/ml) after 60 minutes of drug therapy and remained at this level for four hours. Hyperlactatemia occurred at four hours (4.7 ± 0.8 mmol/liter) and the plasma lactate/pyruvate ratio increased in a 10:1 ratio. Both drugs significantly reduced glomerular filtration rate, sodium, potassium, and chloride excretion and urinary flow rate. Changes in acid-base homeostasis, plasma aldosterone, or renal potassium excretion did not contribute to ritodrine- or terbutaline-induced hypokalemia. In 83 women with preterm labor randomly assigned to ritodrine (N = 42) or terbutaline (N = 41), the maximum decrease in plasma potassium occurred after six hours of drug infusion. During Holter monitoring, 3 of 14 women treated with ritodrine or terbutaline developed symptomatic cardiac arrhythmias at the lowest plasma potassium, while no women treated with saline and morphine (N = 12) developed cardiac arrhythmias (P = 0.14). We conclude that ritodrine and terbutaline induce profound hypokalemia by stimulating cellular potassium uptake and both drugs cause significant renal sodium and fluid retention and cardiac arrhythmias. Careful monitoring of electrolytes, fluid balance, and cardiac rhythm should occur during tocolytic therapy with ritodrine or terbutaline.

To evaluate the potential for regulation of the insulin receptor substrate IRS-1, we have cloned the mouse IRS-1 gene, identified its promoter, and analyzed promoter activity in the basal state and in response to stimulation. The 5'-region of the mouse IRS-1 gene lacks typical CAAT and TATA boxes but contains nine potential Sp1 binding sites consistent with a housekeeping gene. The 5'-region of the IRS-1 gene also has significant regions of homology with the promoters of the progesterone receptor gene, the insulin-like growth factor I receptor gene, and the androgen receptor gene. Multiple transcription start sites were identified 0.4-1.2 kilobases (kb) upstream from the start codon. Using a chloramphenicol acetyl transferase assay in Chinese hamster ovary (CHO) cells, basal promoter activity was present in the 3.2 kb 5'-flanking region of IRS-1 gene. Within this region, there were 184-base pair and 60-base pair negative regulatory elements at -3.2 kb and -1.6 kb surrounded by positive elements. By gel shift assay, a nuclear factor was identified in CHO cells which binds to -1606 and -1586 sequence in the negative regulatory element and appears to be distinct from C/EBP, CREB, and AP-1. In 3T3-F442A adipocytes dexamethasone treatment significantly decreased IRS-1 mRNA and IRS-1 protein. This was due to a decrease in the half-life of IRS-1 mRNA, with no change in IRS-1 promoter-chloramphenicol acetyl transferase activity. Insulin also decreased IRS-1 protein by approximately 60% within 9 h but did so without altering IRS-1 mRNA levels or chloramphenicol acetyl transferase activity. Thus, both insulin and dexamethasone down-regulate IRS-1 expression at the posttranscriptional level; with insulin this is probably due to an effect on protein half-life, whereas with dexamethasone the effect is due to a change in the half-life of IRS-1 mRNA.

BACKGROUND. Merkel cell carcinoma is an uncommon malignancy of the skin that often portends a poor prognosis. Since its first description by Toker in 1972, a plethora of case reports and articles regarding the etiopathogenesis and treatment have been published spanning multiple medical and surgical disciplines. Much confusion still exists regarding the diagnosis and treatment of this ominous tumor. OBJECT. Through extensive review of the medical, surgical, and pathological literature, to collate the observations of multiple investigators and summarize these findings. METHODS. Articles from journals of multiple subspecialties were carefully reviewed with particular emphasis placed on epidemiology, prognosis, histology, immunohistochemistry, electron microscopy, tumor origin, treatment, and work-up of Merkel cell carcinoma. RESULTS. Merkel cell carcinoma is an aggressive malignant neoplasm. Local recurrence develops in 26-44% of patients despite therapy. Up to three-fourths of patients eventually develop regional nodal metastases with distant metastases occurring in one-third of all patients. Reported bverall 5-year survival rates range from 30% to 64%. CONCLUSION. Treatment recommendations unfortunately are based more on anecdotal than scientific data because of the rarity of the tumor and its recognized high risk. Most authors recommend wide local excision of the primary lesion and regional lymph node resection if lymph nodes are palpable followed by x-irradiation of both the postsurgical bed and lymph node basin. The role of elective lymph node resection in the absence of clinically positive nodes remains controversial. Dermatol Surg 1995 ;21 :669-683.

The mouse IRS-1 gene has been cloned and its structure determined. Mouse IRS-1 differs from rat by the absence of the potential C-terminal nucleotide binding site. Otherwise, the predicted IRS-1 protein is highly conserved between mouse, rat and humans, especially in the possible phosphorylation sites. The highly conserved nature of IRS-1 suggests the importance of these domains in the function of IRS-1 or its association with other proteins.

Insulin receptor substrate-1 is a major substrate of insulin receptor Tyr kinase. We have now cloned the IRS-1 cDNA from human skeletal muscle, one of the most important target tissues of insulin action, localized and cloned the human IRS-1 gene, and studied the expression of the protein in Chinese hamster ovary cells. Human IRS-1 cDNA encodes a 1242 amino acid sequence that is 88% identical with rat liver IRS-1. The 14 potential Tyr phosphorylation sites include 6 Tyr-Met-X-Met motifs and 3 Tyr-X-X-Met motifs that are completely conserved in human IRS-1. Human IRS-1 has >50 possible Ser/Thr phosphorylation sites and one potential ATP-binding site close to the NH2-terminal. The human IRS-1 gene contains the entire 5ʹ-untranslated region and protein coding region in a single exon and was localized on chromosome 2 q36–37 by in situ hybridization. By Northern blot analysis, IRS-1 mRNA is rare and consists of two species of 6.9 and 6 kilobase. By using quantitative polymerase chain reaction after reverse transcription of total RNA from human fetal tissues, IRS-1 mRNA could be identified in all tissues. When human IRS-1 cDNA was expressed in Chinese hamster ovary cells, the protein migrated between 170,000–180,000 Mr in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and was rapidly Tyr phosphorylated upon insulin stimulation. Thus, IRS-1 is widely expressed and highly conserved across species and tissues. Compared with rat protein, human IRS-1 contains more potential Ser/Thr phosphorylation sites and only one nucleotide binding site. The entire protein coding sequence is contained within a single exon.

Control of two basic ionization processes in dielectrics i.e. photo ionization and electron–electron impact ionization on intrinsic time and intensity scales is investigated experimentally and theoretically. Temporally asymmetric femtosecond pulses of identical fluence, spectrum and pulse duration result in different final free electron densities. We found that an asymmetric pulse and its time reversed counterpart address two ionization processes in a different fashion. This results in the observation of different thresholds for surface material modification in sapphire and fused silica. We conclude that control of ionization processes with tailored femtosecond pulses is suitable for robust manipulation of breakdown and thus control of the initial steps of laser processing of high band gap materials.

Laser control of two basic ionization processes in dielectrics on intrinsic time and intensity scales with temporally asymmetric pulse trains is investigated. We create robust structures one order below the diffraction limit.

Transparent solids may absorb energy from a laser beam of sufficient high intensity. Several models are under consideration to describe the evolution of the free-electron density. Some of these models keep track of the energy distribution of the electrons. In this work we compare different models and give rules to estimate which one is applicable. We present the inclusion of a term in the multiple rate equation approach, recently introduced, describing fast recombination processes to exciton states. Moreover, we present experimental results with temporally asymmetric femtosecond laser pulses, impinging on a surface of fused silica. We found different thresholds for surface material modification with respect to an asymetric pulse and its time reversed counterpart. This difference is due to a different time-and-intensity dependence of the main ionization processes, which can be controlled with help of femtosecond shaped laser pulses.

The Echinococcus granulosus genome was searched for microsatellites using 8 different repeated oligonucleotides as probes (GT15, CT15, AT15, CG15, CAT10, CAA10, CGG10 and CATA10). Southern blot experiments revealed that DNA regions containing GT, CAA, CATA and CT repeats are the most frequent in the E. granulosus genome. AT and CG probes showed no hybridization signal. Two loci containing CA/GT (Egmsca1 and Egmsca2) and 1 locus containing GA/CT (Egmsga1) repeats were cloned and sequenced. The locus Egmsca1 was analysed in 73 isolates from Brazil and Argentina whose strains were previously characterized. Brazilian isolates from cattle strain and Argentinean isolates from camel strain were monomorphic and shared the allele (CA)7. Argentinean isolates of sheep and Tasmanian sheep strains shared 2 alleles [(CA)8 and (CA)10] with Brazilian isolates of sheep strain. The allele (CA)11 was found only in Brazilian isolates of sheep strain at a low frequency. The Brazilian and the Argentinean sheep strain populations were tested for the Hardy-Weinberg equilibrium, and only the former was in agreement with the expectations. No polymorphism was found among individual protoscoleces from a single hydatid cyst, validating the utilization of pooled protoscoleces from 1 cyst, grouped as an isolate, in population studies. This work describes for the first time the isolation and characterization of microsatellites from E. granulosus.

OBJECTIVE To demonstrate the efficacy, tolerability, and safety of acarbose compared with placebo in patients with type 2 diabetes inadequately controlled with diet and insulin. RESEARCH DESIGN AND METHODS A multicenter randomized double-blind placebo-controlled parallel-group comparison study was conducted. The trial was 26 weeks with a 2-week screening period and a 24-week period of treatment with acarbose or placebo, with forced titration from 25 mg t.i.d. to 50 mg t.i.d. after 4 weeks, and titration of 50 mg t.i.d. to 100 mg t.i.d. after 12 weeks based on glucose control. The dosage of insulin was toremain stable. The primary efficacy variable was mean change from baseline in HbA1c, and secondary efficacy variables included mean changes in fasting and postprandial plasma glucose and triglyceride levels. RESULTS The addition of acarbose to the treatment of patients receiving background insulin and diet therapy resulted in a statistically significant reduction in mean HbA1c of 0.69% compared with placebo. Therewere statistically significant reductions in postprandial plasma glucose and glucose area under the curve, and in postprandial serum triglyceride levels in the acarbose-treated patients. Gastrointestinal side effects were more frequently reported in the acarbose-treated patients. There were no significant differences in hypoglycemic events or liver transaminase elevations between groups. CONCLUSIONS This study demonstrated that the addition of acarbose to patients with type 2 diabetes who are inadequately controlled with insulin and diet is safe and generally well tolerated and that it significantly lowers HbA1c and postprandial glucose levels.

The use of coal in the iron and steel industry located in coke oven sites generated an important amount of tar, contaminated by polycyclic aromatic hydrocarbons, phenols, cyanides and ammonium. This mixture of compounds created contaminated soils areas which need to be remediated for groundwater protection and safe reuse of ancient industrial sites. Generally the bioremediation of PAH contaminated soil is possible but the limited bioavailability of heavier compounds and the unknown behaviour of some generated metabolites is questionable with respect to the feasibility and the efficiency of the proposed techniques. As an alternative to excavation and incineration of contaminated soils, and to enhance leaching treatment using tensioactive molecules, bioremediation has been tested in this work from laboratory trials (batch biodegradation study based on a constant aeration) to on site landfarming processes (pilot scale landfarming test with the addition of hydrogen peroxyde and surfactants). On each of these experiments not only the biodegradation but also the toxicity in soils were followed. The classical analytical study is reinforced by ecotoxicological data that can show the bioavailability and the environmental hazard of a given pollutant.

Supercritical fluids have both gas- and liquid-like properties. They exhibit gas-like mass-transfer properties and liquid like solvatation characteristics. Up to now, the most common fluid has been supercritical CO2 because of its reasonable critical properties, low toxicity and chemical inertness.

The principal substrate for the insulin and insulin-like growth factor-1 (IGF-1) receptors is the cytoplasmic protein insulin-receptor substrate-1 (IRS-1/pp185). After tyrosine phosphorylation at several sites, IRS-1 binds to and activates phosphatidylinositol-3'-OH kinase (PI(3)K) and several other proteins containing SH2 (Src-homology 2) domains. To elucidate the role of IRS-1 in insulin/IGF-1 action, we created IRS-1-deficient mice by targeted gene mutation. These mice had no IRS-1 and showed no evidence of IRS-1 phosphorylation or IRS-1-associated PI(3)K activity. They also had a 50 per cent reduction in intrauterine growth, impaired glucose tolerance, and a decrease in insulin/IGF-1-stimulated glucose uptake in vivo and in vitro. The residual insulin/IGF-1 action correlated with the appearance of a new tyrosine-phosphorylated protein (IRS-2) which binds to PI(3)K, but is slightly larger than and immunologically distinct from IRS-1. Our results provide evidence for IRS-1-dependent and IRS-1-independent pathways of insulin/IGF-1 signalling and for the existence of an alternative substrate of these receptor kinases.

Scabies remains a significant source of morbidity in nursing home residents because of its highly contagious nature. It is characterized by severe pruritus and papules, pustules, burrows, nodules, and occasionally urticarial lesions. Lesions are commonly found on the wrists, finger webs, antecubital fossae, axillae, areolae, periumbilical region, lower abdomen, genitals, and buttocks. Diagnosis is based on the history, physical examination, and demonstration of mites, eggs, or scybala on microscopic examination. Several topical scabicides are available, but permethrin cream appears to be less toxic and more effective in cases that are resistant to other agents. Successful management requires evaluation of individuals with close patient contact.

We present experiments to prepare highly ordered nanochannels with subdiffraction dimensions on fused silica surfaces with femtosecond laser light. For this purpose, we exploit the strongly enhanced near field of highly ordered triangular gold nanoparticles. We demonstrate that after a single laser shot, 6 μm long nanochannels with a mean depth of 4 nm and an average width of 96 nm, i.e., well below the diffraction limit, are generated. These nanochannels are prepared by ablation, caused by the localization of the near field. The crucial parameters, besides the applied fluence, are the polarization direction of the incoming laser light with respect to the triangular nanoparticles and the size of the nanoparticles.

The on-line analysis of gas streams containing ultra low-level concentrations of CO2 over extended time periods presents a unique analytical problem. In the absence of a CO2 preconcentration step, many commercially available instruments used for routine gas analysis lack either the sensitivity or stability for ultra low-level CO2 monitoring. This paper will address two relatively inexpensive (

Cardiopulmonary bypass may, by necessity, have to be performed in patients who are frankly hypothyroid. In treating five such patients, all of whom required coronary revascularization, it was noted that fluid balance during perfusion was considerably different than that in the normal population. In order to attempt to evaluate this difference, ten consecutive euthyroid patients having revascularization and the five hypothyroid patients were compared to correlate all fluid absorbed and excreted with the duration of bypass, the serum sodium, and subsequent weight gain. Fluid intake, urine output, and retained fluid were significantly elevated in the hypothyroid as compared to the euthyroid group, while serum sodium following operation was not significantly different. While there are considerable data indicating that hypothyroidism is associated with abnormal salt and water excretion, there is no information concerning the alterations which occur during cardiopulmonary bypass. The present study indicates that hypothyroidism is associated with significant diuresis (without administration of exogenous diuretic agents during cardiopulmonary bypass). The proposed explanation for this diuresis rests with the assumption that with cardiopulmonary bypass and appropriate fluid administration, the contracted blood volume in hypothyroid patients expands acutely and a diuresis results.

Syringacin 4-A, a bacteriocin produced by Pseudomonas syrinagae 4-A, was obtained by induction with ultraviolet irradiation or mitomycin C. Approximately 1,000-fold purification of the bacteriocin was achieved by manganous chloride precipitation, differential centrifugation, and chromatography on hydroxyapatite columns. The purified syngacin was homogeneous on hydroxyapatite columns and sucrose density gradients; it also sedimented as a single entity in the analytical ultracentrifuge. The buoyant density of purified syringacin in cesium chloride was 1.294 g/ml. The sedimentation coefficient was calculated as 120 S , and the diffusion coefficient was 6.49 × 10 −8 cm 2 /s. The molecular weight was calculated as 1.6 × 10 7 from physical data and 1.7 × 10 7 from biological data. The syringacin was composed of about 88.4% protein, 8.5% arabinose, 2.2% galacturonic acid, and 0.7% glucosamine. Amino acid analysis indicated a predominance of leucine (12.1%), aspartic acid (12.2%), and glutamic acid (12.7%). The ultraviolet spectrum showed a maximum absorbance peak at 276 nm. The syringacin was heat and alcohol sensitive, but resistant to trypsin, chymotrypsin, carboxypeptidase, Pronase, protease, lysozyme, steapsin, deoxyribonuclease, and ribonuclease. Maximum pH stability was between 5 and 8. Crude bacteriocin was stable at room temperature for at least a year, and purified material was stable for at least 3 months at 4 C.