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Different screening methods are being developed to generate adeno-associated viral vectors (AAV) with the ability to bypass the blood-brain barrier (BBB) upon intravenous administration. Recently, the AAV9P31 stood out as the most efficient version among a library of peptide-displaying capsids selected in C57BL/6 mice using RNA-driven biopanning. In this work we have characterized in detail its biodistribution in different mouse strains (C57BL/6 and Balb/c), as well as in Sprague Dawley rats and non-human primates (Macaca fascicularis). Using GFP and NanoLuc reporter genes, we confirmed homogeneous infection and transgene expression across the CNS of mice injected intravenously with AAV9P31. A more restricted pattern was observed upon either intracerebroventricular or intraparenchymal injection. Following intravenous delivery, region- and cell-specific differential patterns of transduction were observed in the mouse brain, including a preferential transduction of astrocytes and neurons in the cerebral cortex and striatum, whereas neurons were the only transduced cell type in subcortical locations across the hippocampus, thalamus, hypothalamus, mesencephalon, brainstem and cerebellum. Furthermore, transduced microglial cells were never found in any CNS location. Peripheral organs transduced upon intravenous administration included lung, liver, peritoneum, heart and skeletal muscle. However, a comparable performance of AAV9P31 to bypass the BBB in rats and macaques was not observed, although a more limited neuronal transduction was found in the brainstem of rats upon intravenous delivery. Finally, intracerebroventricular delivery in macaques resulted in neuronal transduction in cortical, subcortical structures and cerebellum following a patchy pattern. In conclusion, the widespread CNS transduction obtained in mice upon intravenous delivery of AAV9P31 represents a powerful tool for modeling a wide variety of neurological disorders as well as an appealing choice for the evaluation of gene therapy-based therapeutics.

ABSTRACTIntroductionVentilator-associated pneumonia (VAP) is common; its prevalence has been highlighted by the Covid-19 pandemic. Even young patients can suffer severe nosocomial infection and prolonged mechanical ventilation. Multidrug-resistant bacteria can spread alarmingly fast around the globe and new antimicrobials are struggling to keep pace; hence physicians must stay abreast of new developments in the treatment of nosocomial pneumonia and VAP.Areas CoveredThis narrative review examines novel antimicrobial investigational drugs and their implementation in the ICU setting for VAP. This paper highlights novel approaches such as monoclonal antibody treatments for P. aeruginosaand S. aureusand phage antibiotic synthesis. This paper also examines mechanisms of resistance in Gram-negative bacteria, virulence factors, and inhaled antibiotics and questions what may be on the horizon in terms of emerging treatment strategies.Expert opinionThe postantibiotic era is rapidly approaching, and the need for personalized medicine, point-of-care microbial sensitivity testing, and development of biomarkers for severe infections is clear. Results from emerging and new antibiotics are encouraging, but infection control measures and de-escalation protocols must be employed to prolong their usefulness in critical illness.

Background:As nursing colleges seek to respond to the demands of the profession for nurses who are globally engaged and of the students for global health educational experiences, Riner's Globally Engaged Nursing Education framework is an effective tool for developing and evaluating an experience.Method:Using Riner's framework, faculty and students at a nursing college evaluate an inaugural cultural exchange program between their U.S.-based college and a partner in India.Results:The framework helps the team identify the strengths of the program, as well as areas for improvement for future global endeavors. The framework as an evaluation tool is also critiqued in light of this process.Conclusion:Overall, this inaugural program was a success and with this evaluation will inform future cultural exchanges between these institutions. Overall, this inaugural program was a success and with this evaluation will inform future cultural exchanges between these institutions. [[J Nurs Educ. 2019;58(12):704–711.]

The temporal relationship between global glaciations and the Great Oxidation Event (GOE) suggests that climate change played an important role in Earth's oxygenation. The potential role of temperature is captured by the stratigraphic proximity between glacial deposits and sediments containing mass‐independent fractionation of sulfur isotopes (MIF‐S). We use a time‐dependent one‐dimensional photochemical model to investigate whether temperature changes associated with global glaciations can drive oscillations in atmospheric O2levels and MIF‐S production across the GOE. We find that extreme climate change can cause atmospheric O2to oscillate between pre (<10−6times the present atmospheric level, PAL) and post‐GOE (>10−5PAL) levels. Post‐glacial hot‐moist greenhouse climates lead to post‐GOE O2levels because the abundant H2O vapor and oxidizing radicals drive the depletion of reduced species. This pattern is generally consistent with the MIF‐S signal observed in the sedimentary record, suggesting a link between global glaciations and O2oscillations across the GOE. The Great Oxidation Event was the most significant environmental and chemical transformation in Earth's history, marking the first time oxygen accumulated in the atmosphere around 2.4 billion years ago. Oxygen increased from below one millionth (low) to at least one‐thousandth of a percent (intermediate) of the present oxygen concentration during this event. However, measurements of geochemical oxygen proxies suggest that oxygen levels oscillated between low and intermediate levels before stabilizing after this event. The first rise of atmospheric oxygen occurred during a period of extreme climate variability indicated by the presence of glacial rock deposits around this time. In this study, we use a time‐dependent photochemical model to show that extreme temperature changes caused by global glaciations can drive oscillations in atmospheric oxygen levels across the Great Oxidation Event (GOE). Our results can help explain why atmospheric oxygen shows drastic changes across the GOE in a way that is consistent with the geochemical record. Across the Great Oxidation Event (GOE), extreme climate change linked to global glaciations can drive oscillations in atmospheric O2levels and mass‐independent fractionation of sulfur isotopes (MIF‐S) productionGlacial climates and hot‐moist greenhouse climates were likely characterized by pre‐GOE and post‐GOE O2levels respectivelyTemperature changes associated with global glaciations can help explain the MIF‐S record across the GOE Across the Great Oxidation Event (GOE), extreme climate change linked to global glaciations can drive oscillations in atmospheric O2levels and mass‐independent fractionation of sulfur isotopes (MIF‐S) production Glacial climates and hot‐moist greenhouse climates were likely characterized by pre‐GOE and post‐GOE O2levels respectively Temperature changes associated with global glaciations can help explain the MIF‐S record across the GOE

An intercomparison of the radio-chronometric ages of four distinct plutonium-certified reference materials varying in chemical form, isotopic composition, and period of production are presented. The cross-comparison of the different 234U/238Pu, 235U/239Pu, 236U/240Pu, and 241Am/241Pu model purification ages obtained at four independent analytical facilities covering a range of laboratory environments from bulk sample processing to clean facilities dedicated to nuclear forensic investigation of environmental samples enables a true assessment of the state-of-practice in “age dating capabilities” for nuclear materials. The analytical techniques evaluated used modern mass spectrometer instrumentation including thermal ionization mass spectrometers and inductively coupled plasma mass spectrometers for isotopic abundance measurements. Both multicollector and single collector instruments were utilized to generate the data presented here. Consensus values established in this study make it possible to use these isotopic standards as quality control standards for radio-chronometry applications. Results highlight the need for plutonium isotopic standards that are certified for 234U/238Pu, 235U/239Pu, 236U/240Pu, and 241Am/241Pu model purification ages as well as other multigenerational radio-chronometers such as 237Np/241Pu. Due to the capabilities of modern analytical instrumentation, analytical laboratories that focus on trace level analyses can obtain model ages with marginally larger uncertainties than laboratories that handle bulk samples. When isotope ratio measurement techniques like thermal ionization mass spectrometry and inductively coupled plasma mass spectrometry with comparable precision are utilized, model purification ages with similar uncertainties are obtained.

Aging is associated with an exaggerated GLP-1 secretory response. However, this response was not sufficient to increase insulin release and overcome insulin resistance in older subjects with IGT.

The effect of different cathode buffer layers on the performance of inverted organic solar cells (OSCs) fabricated with {poly[[2,6'-4,8-di(5-ethylhexylthienyl)benzo[1,2-b;3,3-b]dithiophene][3-fluoro-2-[(2-ethylhexyl) carbonyl] thieno[3,4-b]thiophenediyl]] (PTB7-Th):[6,6]-phenyl-C71-butyric acid methyl} (PC70BM) as active blend layer is studied using device simulator Silvaco/ATLAS TCAD. The parameters used in the simulations were extracted in fabricated OSCs, using the metal-insulator-metal model, obtaining very good agreement between measured and simulated current density (JSC), open-circuit voltage (VOC), fill factor, and power conversion efficiency (PCE). The enhanced performance observed for devices where either 10 nm of poly[(9,9-bis(3-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene) (PFN), 0.6 nm of lithium fluoride (LiF) layer, or the combination of these two materials, was very well reproduced by simulation. Results indicate that the described procedure can be used to predict the behavior of new buffer layers in OSCs. The PCEs values obtained by simulation were 10.90%, 10.45%, 10.38%, 9.03%, and 7.60% for OSCs with cathode buffer layer consisting of the stack PFN/LiF, PFN, LiF/PFN, LiF and without cathode buffer layer, respectively, which agree well with measured values.

Industrial processes look for maximum production with deposits of high purity, good physical apearence AF and high profitability. Problems during the deposit as a low-quality, low current efficiency EC and high energy consumption CE are present. One solution has been the use of organic additives in small quantities. This work sought to optimize the process with the addition of additives to the electrolyte of ZnSO4 analyzing the effects caused on the basis of the EC, CE and AF. Furthermore, X-Ray diffraction was used and scanning electron microscopy to analyze the morphology of the crystals. Additives used were tetramethyl-ammonium chloride CTMA, tetrabutylammonium chloride CTBA, sodium dodecyl sulfate (DSS), decylamine (DA) and 1-decanol (DE). With additives of short-chain, we obtained good results in relation to the AF, EC, CE and orientation of the crystals deposited.

Development of control systems for power plants must demonstrate satisfactory real-time performance in both, the development and the target platforms, before going into actual operation. This paper presents the simulation of a gas turbine driven electric generator and its control system to assess their performance in a real-time PC-based development platform. All programming was built with the Matlab/Simulink technical computing environment. The combustion turbogenerator 14th order model reproduces the whole dynamics in all operating stages, at start-up, from turngear-speed up to synchronization-speed, synchronization, and generation, from minimum-load up to peak-load conditions. The control system comprises the automation sequences and the feedback control loops, including speed, voltage, active power and reactive power controls. Real-time simulation experiments are presented for each operating stage. Results reveal appropriate real-time performance of the combustion turbogenerator and the control system models.

The reaction of bis(trimethylsilyl)ketene acetals 2with N‐heterocycles containing either one or two nitrogen atoms in the presence of triflic anhydride has been examined and the structures of the resulting products compared with those obtained by using methyl chloroformate as the activating agent. Whereas pyridine, pyrazine, quinoxaline and pyrimidine led to the same type of fused δ‐ or γ‐lactones 4, 6, 8, 10and 11as with methyl chloroformate, the behaviour of pyridazine appeared to be peculiar. In the presence of methyl chloroformate, this heterocycle led to δ‐lactones 16via stable dihydropyridazines, with triflic anhydride, the direct formation of γ‐lactones 20was observed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) Whereas pyridine, pyrazine, quinoxaline and pyrimidine react with bis(trimethylsilyl)ketene acetals in the presence of both methyl chloroformate and triflic anhydride to give the same type of lactonization reactions, pyridazine appears to be peculiar, giving δ‐lactones with the first activating agent and γ‐lactones with the second one.

Cis-element identification is a prerequisite to understand transcriptional regulation of gene loci. From analysis of a limited number of conserved gene loci, sequence comparison has proved a robust and efficient way to locate cis-elements. Human and mouse GATA1 genes encode a critical hematopoietic transcription factor conserved in expression and function. Proper control of GATA1 transcription is critical in regulating myeloid lineage specification and maturation. Here, we compared sequence and systematically mapped position of DNase I hypersensitive sites, acetylation status of histone H3/H4, and in vivo binding of transcription factors over approximately 120 kilobases flanking the human GATA1 gene and the corresponding region in mice. Despite lying in approximately 10 megabase (Mb) conserved syntenic segment, the chromatin structures of the 2 homologous loci are strikingly different. The 2 previously unidentified hematopoietic cis-elements, one in each species, are not conserved in position and sequence and have enhancer activity in erythroid cells. In vivo, they both bind the transcription factors GATA1, SCL, LMO2, and Ldb1. More broadly, there are both species- and regulatory element–specific patterns of transcription factor binding. These findings suggest that some cis-elements regulating human and mouse GATA1 genes differ. More generally, mouse human sequence comparison may fail to identify all cis-elements.

Cis-element identification is a prerequisite to understand transcriptional regulation of gene loci. From analysis of a limited number of conserved gene loci, sequence comparison has proved a robust and efficient way to locate cis-elements. Human and mouse GATA1genes encode a critical hematopoietic transcription factor conserved in expression and function. Proper control of GATA1transcription is critical in regulating myeloid lineage specification and maturation. Here, we compared sequence and systematically mapped position of DNase I hypersensitive sites, acetylation status of histone H3/H4, and in vivo binding of transcription factors over approximately 120 kilobases flanking the human GATA1gene and the corresponding region in mice. Despite lying in approximately 10 megabase (Mb) conserved syntenic segment, the chromatin structures of the 2 homologous loci are strikingly different. The 2 previously unidentified hematopoietic cis-elements, one in each species, are not conserved in position and sequence and have enhancer activity in erythroid cells. In vivo, they both bind the transcription factors GATA1, SCL, LMO2, and Ldb1. More broadly, there are both species- and regulatory element–specific patterns of transcription factor binding. These findings suggest that some cis-elements regulating human and mouse GATA1 genes differ. More generally, mouse human sequence comparison may fail to identify all cis-elements.

The Quaternary Aquifer of the North China Plain is one of the world’s largest aquifer systems and supports an enormous exploitation of groundwater, which has reaped large socio-economic benefits in terms of grain production, farming employment and rural poverty alleviation, together with urban and industrial water-supply provision. Both population and economic activity have grown markedly in the past 25 years. Much of this has been heavily dependent upon groundwater resource development, which has encountered increasing difficulties in recent years primarily as a result of aquifer depletion and related phenomena. This paper focuses upon the hydrogeologic and socio-economic diagnosis of these groundwater resource issues, and identifies strategies to improve groundwater resource sustainability.

A compound feedforward-feedback control scheme for speed control of a turbogas power unit is presented. The two-degrees-of-freedom control scheme is intended to better allocate control actions throughout the power unit startup. The feed forward control path implements a neurofuzzy system that approximates the plant inverse static behavior and generates a control action to support wide-range operation. The feedback control path implements a neurofuzzy PI controller that compensates for uncertainties and small deviations about the intended acceleration pattern. Both control paths complement each other. Feedforward lessens the control effort on the feedback control, and feedback compensates for the transient dynamics not considered by feedforward control. Simulation experiments show that the proposed control scheme effectively manages the turbogas unit speed along the desired acceleration pattern during startup

Fossil-fuel power plants are complex systems currently being required to take on load-following duties with full-range variations in power generation. Most of their control systems consist of decentralized PI control loop configurations supplemented with ad-hoc compensation schemes, intended to minimize the effects of interaction among the control loops caused by the non-linear coupled process dynamics. This paper analyses the viability of an inverse decoupling compensation scheme to lessen control loop interaction to ease wide-range power generation control throughout the power plant operating space. The proposed compensator introduces compensation factors among the control signals, which can be systematically determined from an equivalent process gain matrix that conveys all required information about control loop interaction.

Mast cells are important as sentinel cells in host defense against bacterial infection. Much of their effectiveness depends upon recruiting other immune cells; however, little is known about the mechanisms of this response. CCL20, also known as macrophage inflammatory protein-3alpha (MIP-3alpha), Exodus, and LARC, is a chemokine known to be a potent chemoattractant for immature dendritic cells and T cells. In this study, we examined the human mast cell production of both CCL20 and granulocyte-macrophage colony-stimulating factor (GM-CSF), a critical cytokine for innate immune responses in the lung, in response to Pseudomonas aeruginosa. Reverse transcription-PCR and Western blot analysis demonstrated that the human mast cells (HMC-1) express CCL20 mRNA and are able to produce a significant amount (32.4 ng/ml) of CCL20 protein following stimulation by calcium ionophore and phorbol myristate acetate. Importantly, P. aeruginosa potently stimulated CCL20 production in human cord blood-derived mast cells (CBMC), with production peaking at 6 h after stimulation. This time course of expression was distinct from that of GM-CSF, which peaked after 24 to 48 h. Significant CCL20 production did not occur following immunoglobulin E-mediated activation of CBMC under conditions which induced a substantial GM-CSF response. Interestingly, the CCL20 response of mast cells to P. aeruginosa was relatively resistant to inhibition by the corticosteroid dexamethasone, interleukin-10, or cyclosporine, while GM-CSF production was potently inhibited. However, P. aeruginosa-induced CCL20 production was blocked by the protein kinase C (PKC) inhibitor Ro 31-8220 and a PKC pseudosubstrate. These results support a role for human mast cells in the initiation of immune responses to P. aeruginosa infection.

ABSTRACTMast cells are important as sentinel cells in host defense against bacterial infection. Much of their effectiveness depends upon recruiting other immune cells; however, little is known about the mechanisms of this response. CCL20, also known as macrophage inflammatory protein-3α (MIP-3α), Exodus, and LARC, is a chemokine known to be a potent chemoattractant for immature dendritic cells and T cells. In this study, we examined the human mast cell production of both CCL20 and granulocyte-macrophage colony-stimulating factor (GM-CSF), a critical cytokine for innate immune responses in the lung, in response to Pseudomonas aeruginosa. Reverse transcription-PCR and Western blot analysis demonstrated that the human mast cells (HMC-1) express CCL20 mRNA and are able to produce a significant amount (32.4 ng/ml) of CCL20 protein following stimulation by calcium ionophore and phorbol myristate acetate. Importantly, P. aeruginosapotently stimulated CCL20 production in human cord blood-derived mast cells (CBMC), with production peaking at 6 h after stimulation. This time course of expression was distinct from that of GM-CSF, which peaked after 24 to 48 h. Significant CCL20 production did not occur following immunoglobulin E-mediated activation of CBMC under conditions which induced a substantial GM-CSF response. Interestingly, the CCL20 response of mast cells to P. aeruginosawas relatively resistant to inhibition by the corticosteroid dexamethasone, interleukin-10, or cyclosporine, while GM-CSF production was potently inhibited. However, P. aeruginosa-induced CCL20 production was blocked by the protein kinase C (PKC) inhibitor Ro 31-8220 and a PKC pseudosubstrate. These results support a role for human mast cells in the initiation of immune responses to P. aeruginosainfection.

Several studies have been developed on the hydrophobicity of different strains of Candida albicans, but little is known about the hydrophobic characteristics of Candida parapsilosis, despite the fact that this species is becoming an important pathogen. This work shows a study of the influence of the incubation temperature on the hydrophobicity of C. parapsilosis strain 294, through macroscopic techniques based on contact angles measured on deposited lawns of yeasts and on cell adhesion to solvents hexadecane and chloroform (microbial adhesion to solvents (MATS) test) and through a microscopic technique by using atomic force microscopy (AFM). All of the techniques employed have shown that the yeast surface becomes more hydrophobic when grown at 37 °C than at 22 °C. However, some discrepancies have been found between the behavior of yeasts against hexadecane or chloroform in MATS and the interfacial free energy predictions between the yeasts and each of those liquids calculated from contact angle measurements. On the other hand, AFM techniques have indicated a different temperature influence on the surface properties of the two kinds of patches that lateral force microscopy reveals. Also, all techniques have displayed a similar sensibility to detect the changes induced in the surface characteristics by the incubation temperature, but in this case, AFM shows a different behavior for the different surface patches, too.

Pulmonary infection with Pseudomonas aeruginosa is characterized by massive airway inflammation, which comprises significant cytokine production. Although mast cells are abundant in the lung and are potent sources of various cytokines, a role of mast cells in P. aeruginosa infection remains undefined, and P. aeruginosa-induced signaling mechanisms in mast cells have not been studied previously. Here we demonstrate that human cord blood-derived mast cells, mouse bone marrow-derived mast cells, and the mouse mast cell line MC/9 produce significant amounts of interleukin 6 (IL-6) in response to P. aeruginosa. This response was accompanied by a stimulation of protein kinase Calpha (PKCalpha) phosphorylation and PKC activity and was significantly blocked by the PKC inhibitors Ro 31-8220 and PKCalpha pseudosubstrate. Interestingly, mast cells treated with P. aeruginosa had reduced protein levels of phosphatase 2A catalytic unit (PP2Ac), which prompted us to determine whether a direct association between PKCalpha and PP2A occurs in mast cells. In mouse bone marrow-derived mast cells and MC/9 cells, as well as in the human mast cell line HMC-1, PP2A coimmunoprecipitated with PKCalpha either using PKCalpha- or PP2Ac-specific antibodies, suggesting that PKCalpha and PP2Ac are physically associated in mast cells. The PP2A inhibitor okadaic acid induced P. aeruginosa-like responses in mast cells including increased PKCalpha phosphorylation, stimulated PKC activity, and augmented IL-6 production, the last being blocked by the PKC inhibitor Ro 31-8220. Finally, okadaic acid potentiated the P. aeruginosa-induced IL-6 production. Collectively, these data provide, to our knowledge, the first evidence of both a direct physical association of PP2A and PKCalpha in mammalian cells and their coinvolvement in regulating mast cell activation in response to P. aeruginosa.

The investigation of the chemical constituents from the roots of Psacalium radulifolium, a member of the matarique complex of medicinal plants, which includes several members of the Asteraceae, resulted in the isolation of four new modified eremophilanes:  radulifolin A (4), epi-radulifolin A (5), radulifolin B (6), and radulifolin C (7), together with the known natural substances cacalol, cacalone, epi-cacalone, O-methyl-1,2-dehydrocacalol, adenostin A, decompostin, and neoadenostylone. Antimicrobial evaluation of the extracts and the isolated compounds indicated that cacalol was the major active compound.

The developmental expression of two metabotropic glutamate receptors (mGluR), mGluR1α and mGluR2/3 was evaluated in the rat striatum from birth to adulthood. The mGluR1α receptor subtype displayed a patchy organization perinatally that became more homogeneous after the first postnatal week. The adult pattern of receptor expression consisted of homogeneous punctate profiles spread throughout the striatum. The mGluR2/3 receptor subtype exhibited a unique pattern of ontogenic expression, being associated exclusively with fibers of the internal capsule that penetrate the striatum, during the perinatal period. The protein localization for this subtype spread into the striatal neuropil after the first postnatal week, in parallel to the development of afferent terminations and arborizations to the nucleus. Unlike the ionotropic GluR subunits that are associated with somata and dendrites, neither subtype of metabotropic receptor was associated with neuronal cell bodies within the striatum.

This paper presents a first evaluation of PID-like fuzzy controllers towards the implementation of a multiloop control strategy for fossil fuel power units. Simple fuzzy-PID controllers substitute the conventional PID controllers. Their design using standard characteristics and reduced sets of rules is motivated by the notion that skilful operators make use of only a few control rules to adequately manage the process. Through computer simulations, the robust performance of three promising configurations of fuzzy-PID controllers is evaluated and compared to that of a finely tuned conventional PID, in a single-input-single-output setup, showing improved performance. The multiloop control strategy is implemented and simulation experiments, using a nonlinear model of the power plant, indicate improvement over the PID based configuration.

Bacterial heat shock proteins (Hsps) are abundantly produced during the course of most microbial infections and are often targeted by the mammalian immune response. While Hsps have been well characterized for their roles in protein folding and secretion activities, little attention has been given to their participation in pathogenesis. In the case of Legionella pneumophila, an aquatic intracellular parasite of protozoa and cause of Legionnaires' disease, Hsp60 is uniquely located in the periplasm and on the bacterial surface. Surface-associated Hsp60 promotes attachment and invasion in a HeLa cell model and may alter an early step associated with the fusion of phagosomes with lysosomes. Avirulent strains of L. pneumophila containing defined mutations in several dot/icm genes are defective in localizing Hsp60 onto their surface and are reduced approximately 1000-fold in their invasiveness towards HeLa cells. For the ulcer-causing bacterium Helicobacter pylori, surface-associated Hsp60 and Hsp70 mediate attachment to gastric epithelial cells. The increased expression of these Hsps following acid shock correlates with both increased association with and inflammation of the gastric mucosa. A role for Hsps in colonization, mucosal infection and in promoting inflammation is discussed. Infect. Dis. Obstet. Gynecol. 7:58–63, 1999. © 1999 Wiley-Liss, Inc.

Previous studies have indicated that porcine reproductive and respiratory syndrome virus (PRRSV) can be identified in and transmitted through boar semen. However, the site(s) of replication indicating the origin of PRRSV in semen has not been identified. To determine how PRRSV enters boar semen, five vasectomized and two nonvasectomized PRRSV-seronegative boars were intranasally inoculated with PRRSV isolate VR-2332. Semen was collected three times weekly from each boar and separated into cellular and cell-free (seminal plasma) fractions. Both fractions were evaluated by reverse transcriptase nested polymerase chain reaction (RT-nPCR) for the presence of PRRSV RNA. Viremia and serostatus were evaluated once weekly, and boars were euthanatized 21 days postinoculation (DPI). Tissues were collected and evaluated by RT-nPCR, virus isolation (VI), and immunohistochemistry to identify PRRSV RNA, infectious virus, or viral antigen, respectively. PRRSV RNA was identified in semen from all vasectomized and nonvasectomized boars and was most consistently found in the cell fraction, within cells identified with a macrophage marker. Viral replication as determined by VI was predominately found within lymphoid tissue. However, PRRSV RNA was widely disseminated throughout many tissues, including the reproductive tract at 21 DPI. These results indicate that PRRSV can enter semen independent of testicular or epididymal tissues, and the source of PRRSV in semen is virus-infected monocytes/macrophages or non-cell-associated virus in serum. PRRSV-infected macrophages in semen may result from infection of local tissue macrophages or may originate from PRRSV-infected circulating monocytes or macrophages.

Fifteen hybridomas secreting monoclonal antibodies against human antithrombin III, originating from two mouse strains, have been produced by the cell fusion technique. Eight monoclonal antibodies belong to the class lgG1, five to the class lgG2a, and two to the class lgG2b. All light chains belong to the κ group. No cross-reaction of the monoclonal antibodies have been observed with a crude preparation of albumin nor with α1-antitrypsin and α2-antiplasmin. Five of these monoclonal antibodies exhibit a relatively high avidity for antithrombin III. Inhibition experiments showed that the 15 monoclonal antibodies define seven more or less independent antigenic regions on the antithrombin III molecule. Examination of the effects of these antibodies on the inhibitory capacity of antithrombin III toward thrombin activity, either in the presence or in the absence of heparin, showed that several monoclonal antibodies inhibit the antithrombin III activity and allowed to relate some of the antigenic determinants to functional sites on the antithrombin III molecule.

23 hybridomas secreting monoclonal antibodies against human α2, the fast-acting inhibitor of plasmin present in plasma, have been produced by the cell-fusion technique. Isotyping of the monoclonal antibodies has revealed that 14 monoclonal antibodies belong to the class IgG1, 6 to the class IgG2a, and 3 to the class tgG2b. All light chains belong to the κ group. The specificity and relative avidity of these monoclonals have been determined Using an indirect enzyme-linked immunosorbent assay. 13 monoclonals exhibit a relatively high avidity for α2, 5 are of intermediate avidity, and 5 of low avidity. The epitope specificity of these 23 rnonoclonal antibodies, originating from a single mouse, have been examined in inhibition experiments. A group of 10 monoclonal antibodies exhibit a very similar inhibition pattern. Partial inhibition effects displayed by 10 other antibodies define partially overlapping antigenic regions. The binding of these antibodies seems to produce a conformational change in the α2 molecule, reducing the binding of two other antibodies. The last antibody defines an independent epitope.

Stratigraphic studies and detailed field analyses of brittle and plastic deformations allow the reconstruction of the stress pattern and the tectonic evolution of the central sector of the Mexican Volcanic Belt. Several compressional phases affected the metamorphic basement, while the last one also involved the volcanic cover of Early Miocene age. In Middle Miocene-Early Pliocene times and ENE-WSW extensional phase developed, representing the southern protraction of the Basin and Range Province of the western United States. In Pliocene-Quaternary times there then followed the development of a complicated deformational cycle showing the superficial evidence of a sinistral lateral shear zone. At the beginning the area was affected by a NE-SW compression including reverse, dextral and sinistral strike-slip faulting. This was followed by Early Pleistocene sinistral transtension characterized by a NW-SE direction of least principal stress and sinistral normal-slip faulting. During Late Pleistocene-Holocene times the transtension was concentrated along E-W faults.

23 hybridomas secreting monoclonal antibodies against human a2 , the fast-acting inhibitor of plasmin present in plasma, have been produced by the cell-fusion technique. Isotyping of the monoclonal antibodies has revealed that 14 monoclonal antibodies belong to the class IgG1, 6 to the class IgG2a, and 3 to the class tgG2b. All light chains belong to the ? group. The specificity and relative avidity of these monoclonals have been determined Using an indirect enzyme-linked immunosorbent assay. 13 monoclonals exhibit a relatively high avidity for a2 , 5 are of intermediate avidity, and 5 of low avidity. The epitope specificity of these 23 rnonoclonal antibodies, originating from a single mouse, have been examined in inhibition experiments. A group of 10 monoclonal antibodies exhibit a very similar inhibition pattern. Partial inhibition effects displayed by 10 other antibodies define partially overlapping antigenic regions. The binding of these antibodies seems to produce a conformational change in the a2 molecule, reducing the binding of two other antibodies. The last antibody defines an independent epitope.

"This is a Test: One Girl's Fight with Cancer" is the award-winning play written by students at Washington Irving School in Chicago, Illinois. It follows the life of Shenita Peterson, from the first twinges of what was to be diagnosed as bone cancer through her reluctant return to school, bald and on crutches. This Is a Test is a creative exploration of fear, memory, and healing as well as a staging of a struggle with life-threatening illness.