cssi/SciSciGPT-SciSciNet huggingface dataset:
Dependence of Pituitary Gonadotropin-Releasing Hormone (GnRH) Receptors on GnRH Secretion from the Hypothalamus

Recent studies in male rats have shown that the number of pituitary gonadotropin-releasing hormone (GnRH) receptors is increased by castration and by injections of GnRH. This suggests that GnRH has a positive influence on the number of its own receptors, and that GnRH-binding capacity (GnRHBC) is related to the concentration of GnRH in portal blood. The present study was performed to determine if lesions of the medial basal hypothalamus would prevent the postcastration rise of pituitary GnRH receptors and whether exogenous GnRH administration to lesioned animals would maintain receptor numbers. In sham-lesioned castrate rats, the GnRH-BC increased progressively and was twice the basal level by 3 days after surgery. Large medial basal hypothalamic lesions completely eliminated this rise after castration but did not reduce GnRH-BC in intact (noncastrated) control animals. Serum LH levels were undetectable in lesioned rats, but serum PRL levels were elevated, indicating that the lesions had not damaged the p...
Inhibition of nitric oxide synthesis attenuates alcohol consumption in two strains of alcohol-preferring rats

The effect of the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) on voluntary alcohol consumption was examined in two different strains of alcohol-preferring rats, in a continuous-access, two-bottle-choice paradigm. Compared with the vehicle, intraperitoneal injections of L-NAME significantly and dose-dependently (10, 30, and 60 mg/kg) suppressed alcohol intake and preference in both alcohol-preferring (P) and Fawn-Hooded (FH) rats. The effect of the highest dose of L-NAME was nonspecific; it caused general decreases in consumption of alcohol, water, and food. Repeated injection of L-NAME (30 mg/kg) for 4 consecutive days significantly attenuated alcohol intake, but tolerance developed after 3 days of treatment. A single administration of a high dose of L-NAME (60 mg/kg) did not influence the blood alcohol concentrations, which suggests a possible central effect. Furthermore, a moderate dose of 30 mg/kg L-NAME, which selectively inhibited alcohol intake, did not exert a significant effect on telemetrically measured heart rate, core body temperature, and gross motor activity of alcohol naive Fawn-Hooded rats. These results suggest an involvement of nitric oxide in alcohol drinking behavior. Although the true mechanism(s) of action is not yet clear, it can be speculated that L-NAME may exert its action indirectly by modulating neurotransmitters proposed to be involved in alcohol drinking and/or by influencing other neuronal factors, such as neuronal Ca2+ channels, which have been shown to be involved in alcohol drinking behavior.
PECTIC SUBSTANCES AND FIRMNESS OF CUCUMBER PICKLES AS INFLUENCED BY CACL2, NACL AND BRINE STORAGE

The effects of brine treatments (CaCl2 and NaCl) and storage on pectic substances and texture of cucumber pickles were examined. Firmness of cucumber pickles was closely associated with the solubility characteristics and degree of esterification (DE) of pectic substances. Brining, storage, time of CaCl2 addition and concentration of NaCl and CaCl2 were all observed to influence the characteristics of pectic substances. Important to preventing softening was maintenance of pectic substances not extractable (NXP) by conventional methods, i.e., by water (WSP), the chelator sodium hex-ametaphosphate (CSP), and dilute alkali (OHSP). Erosion of NXP consistently resulted in increased levels of CSP and reduced firmness. Reducing the amount of demethylation of pectins was also associated with maintaining firmness. Although the DE declined rapidly during brining, tissues from treatments that enhanced firmness had pectic substances with the highest DE. CaCl2 added to brine at the beginning of fermentation was most effective in preventing the demethylation of pectins and solubilization of NXP. In contrast, delayed addition of CaCl2 and storage in low NaCl concentration (5% or less) caused greater pectin demethylation, erosion of NXP with concomitant increases in CSP and tissue softening.
Characterization of kinetoplast DNA minicircles in Trypanosoma rangeli

Kinetoplast DNA, the mitochondrial DNA of kinetoplastid protozoans, is a network of interlocked minicircles and maxicircles. We analyzed the sequence organization of minicircle DNAs in the El Tocuyo strain and the San Augustin clone B6 of Trypanosoma rangeli. The frequencies of different minicircle types, as defined by the number of 136-bp conserved regions (CRs), are different in the two strains. About half of the 1.7-kb T. rangeli El Tocuyo minicircles have 1 CR and most of the others have 2. In contrast, most of the 1.6-kb T. rangeli San Augustin minicircles have 2 CRs, while some have four. The CR contains a replication origin at one end and is conserved both within and between the two strains. Comparisons of the T. rangeli El Tocuyo and T. rangeli San Augustin minicircle CRs with minicircle CRs of other kinetoplastid species reveal that they are most similar to those of Trypanosoma cruzi.
Inelastic off-fault response and three-dimensional dynamics of earthquake rupture on a strike-slip fault

[1] Large dynamic stress off the fault incurs an inelastic response and energy loss, which contributes to the fracture energy, limiting the rupture and slip velocity. Using an explicit finite element method, we model three-dimensional dynamic ruptures on a vertical strike-slip fault in a homogeneous half-space. The material is subjected to a pressure-dependent Drucker-Prager yield criterion. Initial stresses in the medium increase linearly with depth. Our simulations show that the inelastic response is confined narrowly to the fault at depth. There the inelastic strain is induced by large dynamic stresses associated with the rupture front that overcome the effect of the high confining pressure. The inelastic zone increases in size as it nears the surface. For material with low cohesion (∼5 MPa) the inelastic zone broadens dramatically near the surface, forming a “flowerlike” structure. The near-surface inelastic strain occurs in both the extensional and the compressional regimes of the fault, induced by seismic waves ahead of the rupture front under a low confining pressure. When cohesion is large (∼10 MPa), the inelastic strain is significantly reduced near the surface and confined mostly to depth. Cohesion, however, affects the inelastic zone at depth less significantly. The induced shear microcracks show diverse orientations near the surface, owing to the low confining pressure, but exhibit mostly horizontal slip at depth. The inferred rupture-induced anisotropy at depth has the fast wave direction along the direction of the maximum compressive stress.
The production of Asian theories of communication: contexts and challenges

The past two or three decades have witnessed an intense interest in rediscovering Asian theories of communication and exploring their applicability to modern communication studies. I myself have been deeply involved in this project for the past thirty years. While this should be welcomed as a much-needed project, it is imperative that we realize that this effort is as important as it is complex and many-sided; there are several perilous pitfalls in the way such as those presented by romanticism, essentialism and ahistoricism. In this article, I discuss some of these issues, and the ways in which we can profitably engage Western formulations of communication, in relation to what I term Type A and Type B theories.
Malignant Glioma: Lessons from Genomics, Mouse Models, and Stem Cells

Eighty percent of malignant tumors that develop in the central nervous system are malignant gliomas, which are essentially incurable. Here, we discuss how recent sequencing studies are identifying unexpected drivers of gliomagenesis, including mutations in isocitrate dehydrogenase 1 and the NF-κB pathway, and how genome-wide analyses are reshaping the classification schemes for tumors and enhancing prognostic value of molecular markers. We discuss the controversies surrounding glioma stem cells and explore how the integration of new molecular data allows for the generation of more informative animal models to advance our knowledge of glioma's origin, progression, and treatment.
Effects of the N-Terminus of Cardiac Troponin T on Contractile Activation Depend on the Type of Myosin Heavy Chain Isoform

We have previously shown that two specific regions (residues 1-43 and residues 44-73) in rat cardiac troponin T (RcTnT) have divergent effects on contractile function against an α-myosin heavy chain (α-MHC) background (Mamidi et al., Abstract: Biophys J, vol.100, Issue 3, p586a, 2010). Because the effects of Tn isoforms are modulated by an interplay with MHC, we hypothesized that the divergent effects of residues 1-43 and residues 44-73 in cTnT would be further modulated by a shift in MHC isoform to β-MHC. This has a direct bearing on understanding the effects of alterations in cTnT and MHC isoforms not only in health but also in disease. We generated two recombinant mutants (RcTnT1-43 and RcTnT44-73) by deleting residues 1-43 and 44-73 in RcTnT, respectively. We studied contractile function by reconstituting RcTnT1-43 and RcTnT44-73 recombinant proteins into detergent-skinned papillary muscle fibers from normal rat hearts (α-MHC) and propylthiouracil-treated rat hearts (β-MHC). Our data shows that functional alterations induced by RcTnT1-43 and RcTnT44-73 were different in α-MHC vs. β-MHC fibers. For example, RcTnT1-43 decreased both Ca2+-activated maximal tension (by ∼46%) and myofilament Ca2+-sensitivity (by 0.09 pCa units) in α-MHC fibers. However, RcTnT1-43 modestly decreased maximal tension (by ∼18%), with no effect on Ca2+-sensitivity in β-MHC fibers. Thus, the desensitizing effect of RcTnT1-43 was attenuated by β-MHC. Ca2+-activated maximal tension data were supported by myofiber dynamic stiffness measurements. Another major finding is that RcTnT44-73 abolished the sarcomere length-dependent increase in Ca2+-sensitivity in β-MHC, but not in α-MHC fibers. Thus, our data demonstrates that the functional outcome of the N-terminus of cTnT is modulated by the type of MHC isoform present.
DEVELOPMENT AND USE OF SPECIFIC POLYMERASE REACTION FOR THE DETECTION OF AN ORGANISM RESEMBLING EHRLICHIA SP. IN WHITE-TAILED DEER

The role of white-tailed deer (Odocoileus virginianus) in the epidemiology of Ehrlichia chaffeensis and the agent of human granulocytic ehrlichiosis (HGE) is not fully understood, and diagnostic procedures may be complicated by the recent detection of 16S rDNA sequence from an Ehrlichia sp.-like organism in wild deer. A specific forward primer (DGA) and an Ehrlichia spp. reverse primer (GA1UR) were constructed to amplify this new, distinct Ehrlichia sp.-like 16S rDNA. The DGA primer, a forward primer specific for E. chaffeensis (DCH), and a forward primer specific for the E. phagocytophila genogroup (GE9f) were each used with GA1UR in nested polymerase chain reactions to amplify 16S rDNA sequences from control samples containing the deer Ehrlichia sp.-like organism, E. chaffeensis, or the HGE agent. Primer pairs DGA/GA1UR and DCH/GA1UR specifically amplified 16S rDNA sequences from the corresponding target organism, whereas GE9f/GA1UR amplified 16S rDNA sequence from both the HGE agent and the deer Ehrlic...
Breast cancer and electromagnetic fields--a review.

Abstract PURPOSE: Several statements have been issued to the effect that no consistent, significant link has been demonstrated between cancer and electromagnetic fields (EMF). However, there continues to be much interest in a possible association with breast cancer, in part because breast cancer risk is substantially higher in industrialized countries than in other areas, and electric power generation and consumption is one of the hallmarks of industrialized societies. In 1987, Stevens proposed a biological mechanism whereby two products of electric power generation, EMF and light at night, might contribute to mammary carcinogenesis through inhibition of melatonin. METHODS: We conducted a comprehensive review of the epidemiologic literature and hypothesized mechanisms pertaining to EMF exposure and the risk of breast cancer, in order to assess whether or not there was evidence to suggest a link between EMF and breast cancer. RESULTS: Some occupational epidemiological studies have demonstrated an increased incidence of breast cancer among mainly male electrical workers. It has been difficult to study women, as few are employed in these types of occupations. In all, there have been eleven occupational studies related to breast cancer in women, and statistically significant risk ratios have been observed: 1.98 for pre-menopausal women in occupations with high EMF exposure in one study, 2.17 in all women who worked as telephone installers, repairers, and line workers in another study, and 1.65 for system analysts/programmers, 1.40 for telegraph and radio operators, and 1.27 for telephone operators in a third study. However, six of the studies did not find any significant effects and two found effects only in subgroups. The results of the eight studies of residential exposure and four electric blanket studies have been inconsistent, with most not demonstrating any significant association. However, this might be attributed, at least to some extent, to difficulties in assessing residential exposure in these studies, as well as other methodological considerations. CONCLUSIONS: The biologic plausibility of an association between EMF and breast cancer, coupled with suggestive data from occupational studies and unexplained high incidence rates of breast cancer, suggests that further investigation of this possible association is warranted.
Conformational Changes in the Parathyroid Hormone Receptor Associated with Activation by Agonist

Binding of hormones to their cognate G protein-coupled receptors (GPCRs) induces conformational shifts within the receptor based on evidence from a few hormone-receptor systems. Employing an engineered disulfide bond formation strategy and guided by a previously established model of the PTH-PTH receptor (PTHR)1 bimolecular complex, we set out to document and characterize the nature of agonist-induced changes in this family B GPCR. A mutant PTHR1 was generated which incorporates a Factor Xa cleavage site in the third intracellular loop. Treatment with Factor Xa fragments the receptor. However, if a new disulfide bond was formed before exposure to the enzyme, the fragments remain held together. A set of double cysteine-containing mutants were designed to probe the internal relative movements of transmembrane (TM) helices 2 and TM7. PTH enhanced formation of disulfide bonds in the K240C/F447C and A242C/F447C mutants. For the F238C/F447C mutant, a disulfide bond is formed in the basal state, but is disrupted by interaction with PTH. For the D241C/F447C PTHR1 construct, no disulfide bond formation was observed in either the basal or hormone-bound state. These findings demonstrate that the conformation of PTHR1 is altered from the basal state when PTH is bound. Novel information regarding spatial proximities between TM2 and TM7 of PTHR1 and the nature of relative movements between the two transmembrane regions was revealed. The data confirm and extend the experimentally derived model of the PTH-PTHR1 complex and provide insights at a new level of detail into the early events in PTHR1 activation by PTH.
Cloning of a T-cell receptor β-chain enhancer binding protein

Abstract Several eukaryotic DNA binding proteins have been isolated by screening lambda expression libraries with DNA probes containing their binding site. This strategy has been employed to isolate clones of the factor that interacts with the T-cell receptor β-chain enhancer motif. A cDNA clone encoding a protein similar to YB-1 has been isolated with this. It seems probable that this protein YB, might interact with other proteins and regulate the transcription of the T-cell receptor β-chain gene.
Demand Estimation and Assortment Optimization Under Substitution: Methodology and Application

Assortment planning at a retailer entails both selecting the set of products to be carried and setting inventory levels for each product. We study an assortment planning model in which consumers might accept substitutes when their favorite product is unavailable. We develop an algorithmic process to help retailers compute the best assortment for each store. First, we present a procedure for estimating the parameters of substitution behavior and demand for products in each store, including the products that have not been previously carried in that store. Second, we propose an iterative optimization heuristic for solving the assortment planning problem. In a computational study, we find that its solutions, on average, are within 0.5% of the optimal solution. Third, we establish new structural properties (based on the heuristic solution) that relate the products included in the assortment and their inventory levels to product characteristics such as gross margin, case-pack sizes, and demand variability. We applied our method at Albert Heijn, a supermarket chain in The Netherlands. Comparing the recommendations of our system with the existing assortments suggests a more than 50% increase in profits.
rPRAM: Exploring Redundancy Techniques to Improve Lifetime of PCM-based Main Memory

Future main memory systems will confront the scaling challenges posed by DRAM technology and should adapt themselves to use the emerging memory technologies like Phase Change Memory (PCM, or PRAM). PCM offers advantages such as storage density, non-volatility, and lower energy consumption. However, they are constrained by limited write endurance and reduced performance. In this paper, we propose a novel PCM-based main memory system, rPRAM, that explores advanced redundancy techniques to resuscitate faulty PCM pages and reuse these pages to store data. Our preliminary experiments show that rPRAM has the potential to extend the lifetime of PCM based memory commensurate with the existing schemes like ECP, while incurring only a negligible fraction of hardware cost compared to ECP.
Biventricular Repair After Modified Norwood Operation

Neonates with severe left ventricular outflow tract obstruction (LVOTO) may have a competent left ventricle and mitral valve allowing for biventricular repair (BVR), which can be performed as a primary complete neonatal repair or as a staged procedure. The Norwood procedure, which is characterized by a right ventricle to pulmonary artery (RV-PA) shunt, significantly reduced mortality in this operation. We present our experience with a 2-staged BVR in two neonates with severe LVOTO, in whom we employed the modified Norwood operation (RV-PA shunt) for initial management.
Spirituality of Living and Aging with HIV: A Pilot Study

ABSTRACT Aging with HIV is now possible due to pharmacological advances that are greatly extending life. However, information on aging with HIV is only recently emerging, with little information available about the spiritual lives of those aging with this disease. This pilot study assessed spiritual, psychosocial, and health-related factors in 50 HIV-positive and 50 HIV-negative adults between 30 and 65 years old. The convention of 50 years and over is used in HIV research to indicate older adults and was used in this study as well. Between-group analyses did not reveal differences on attendance of religious events or importance of spirituality. Within-group analyses of the HIV-positive group did show several positive relationships between health-related factors and spirituality; however, age and years diagnosed with HIV were not related to the spirituality items. Interestingly, 72% of the HIV-positive participants indicated that their spirituality changed after receiving their diagnosis and 44% considere...
Long-term results after surgery for autoimmune sclerosing pancreatitis.

Autoimmune sclerosing pancreatitis (ASP) is a recently recognized cause of chronic pancreatitis. The role of operative intervention in this disease is controversial. A single center experience with 161 consecutive pancreatic resections for chronic pancreatitis was retrospectively reviewed. Operative specimens were reanalyzed and assessed for histological features of ASP. Long-term outcome was assessed by patient survey. Eight patients were identified with histological changes consistent with ASP. The pancreatic anatomic configuration according to intraoperative findings and preoperative radiographic evaluation was categorized into (1) diffusely enlarged pancreas (n = 4), (2) localized mass (n = 2), or (3) refractory pancreatic duct disruption without pancreatic enlargement (n = 2). Five patients underwent pancreaticoduodenectomy and three patients underwent distal pancreatectomy. Perioperative morbidity, operative time, and intraoperative estimated blood loss were similar to the same operation for other etiologies of chronic pancreatitis. Biliary obstruction occurred in two patients. Seven patients were alive 5 ± 0.4 years after operation. Good quality of life measured by the SF-36 questionnaire was present in 4 of 7 patients surveyed. Good pain control was achieved with return to work in 5 of 7 patients. Two patients with poor pain control received glucocorticosteroids therapy without improvement in symptoms. Patients with ASP and a mass suspicious for malignancy or refractory duct disruption require operative intervention. Early postoperative outcome, long-term pain control, and improvement in quality of life appear to be good.
Predictors of Outcome following Stroke due to Isolated M2 Occlusions.

Background: Factors influencing outcome after cerebral artery occlusion are not completely understood. Although it is well accepted that the site of arterial occlusion critically influences outcome, the majority of studies investigating this issue has focused on proximal large artery occlusion. To gain a better understanding of factors influencing outcome after distal large artery occlusion, we sought to assess predictors of outcome following isolated M2 middle cerebral artery occlusion infarcts. Methods: We retrospectively analyzed patients with isolated acute M2 occlusion admitted to a single academic center from January 2010 to August 2012. Baseline clinical, laboratory imaging, and outcome data were assessed from a prospectively collected database. Factors associated with a modified Rankin Scale (mRS) score ≤2 in univariable analyses (p Results: 90 patients with isolated M2 occlusion were included in the final analyses. Of these, 69% had a good 90-day outcome which was associated with age 28 ml (OR 11.874, 95% CI 2.630-53.604, p = 0.001), age >80 years (OR 4.953, 95% CI 1.087-22.563, p = 0.039), need for intubation (OR 7.788, 95% CI 1.072-56.604), and history of congestive heart failure (OR 5.819, 95% CI 1.140-29.695) were independent predictors of 90-day mortality (20% of all included patients). Conclusion: While the majority of patients with isolated M2 occlusion stroke has a good 90-day outcome, a substantial proportion of subjects dies by 90 days, as identified by a unique subset of predictors. The knowledge gained from our study may lead to an improvement in the prognostic accuracy, clinical management, and resource utilization in this patient population.
Where knowledge construction, equity, and context intersect: Student learning of science in small groups

To provide insight into the strengths and limitations of using groupwork to promote excellence and equity in science education, the researcher investigated how students using the Complex Instruction model of groupwork constructed scientific knowledge. Eighty sixth-grade students and one life science teacher at an urban middle school participated in this study. Qualitative analysis of videotapes and interviews makes clear that group discussions rarely moved beyond observational or procedural matters, that students of high status (perceived academic ability and popularity) had greater access to their groups' materials and discourse, and that students made few connections among the contexts of school, science, and everyday life. Quantitative analyses of participation during groupwork and performance on unit tests show that high-status students had significantly higher rates of on-task talk than their middle- or low-status counterparts, and that those students who talked more learned more as well. Thus, although groupwork should not be summarily dismissed as an instructional strategy, group tasks and implementation must be further refined to adequately address the dual goals of excellence and equity: Students need greater guidance in how to talk and do science, and teachers, greater assistance in eliminating differences in student participation and achievement. © 1997 John Wiley & Sons, Inc. J Res Sci Teach 34: 1039–1065, 1997.
Post-Traumatic Stress Disorder and Smoking: A Systematic Review

We conducted a systematic review of what is known about the relationship between post-traumatic stress disorder (PTSD) and smoking to guide research on underlying mechanisms and to facilitate the development of evidence-based tobacco treatments for this population of smokers. We searched Medline, PsychINFO, and the Cochrane Central Register of Controlled Trials and identified 45 studies for review that presented primary data on PTSD and smoking. Smoking rates were high among clinical samples with PTSD (40%-86%) as well as nonclinical populations with PTSD (34%-61%). Most studies showed a positive relationship between PTSD and smoking and nicotine dependence, with odds ratios ranging between 2.04 and 4.52. Findings also suggest that PTSD, rather than trauma exposure itself, is more influential for increasing risk of smoking. A small but growing literature has examined psychological factors related to smoking initiation and maintenance and the overlapping neurobiology of PTSD and nicotine dependence. Observational studies indicate that smokers with PTSD have lower quit rates than do smokers without PTSD. Yet a few tobacco cessation treatment trials in smokers with PTSD have achieved quit rates comparable with controlled trials of smokers without mental disorders. In conclusion, the evidence points to a causal relationship between PTSD and smoking that may be bidirectional. Specific PTSD symptoms may contribute to smoking and disrupt cessation attempts. Intervention studies that test behavioral and pharmacological interventions designed specifically for use in patients with PTSD are needed to reduce morbidity and mortality in this population.
Detection and expression of genes for phosphorus metabolism in picocyanobacteria from the Laurentian Great Lakes

Abstract The pelagic regions of Lake Superior and eastern Lake Erie (Laurentian Great Lakes) are typically phosphorus (P)-limited environments, and picocyanobacteria of the genus Synechococcus spp. are prominent primary producers during the summer. As a proxy for their utilization of organic P, the expression of two genes, phnD and phoX , was monitored. The phnD gene encodes the phosphonate binding protein of the ABC-type phosphonate transporter, whereas the phoX gene encodes a calcium-dependent alkaline phosphatase. Furthermore, to assess the ability of freshwater Synechococcus spp. to substitute sulfolipids for phospholipids, sqdX gene (cyanobacterial sulfolipid synthase) expression was examined. We employed PCR primers to detect the presence of all three genes in the endemic Synechococcus spp., and RT-PCR assays of cultured freshwater strains and environmental samples to assess the degree of P-stress in the phytoplankton. We show that the phnD gene was constitutively expressed, suggesting that freshwater picocyanobacteria were metabolizing exogenous phosphonate compounds in Lakes Erie and Superior. By contrast, phoX was regulated by P bioavailability. We also provide evidence that sqdX is expressed during increased growth rates in phosphorus-replete conditions, suggesting that sulfolipid synthesis is not a P conservation mechanism for freshwater Synechococcus spp.
Ventilation Tube Removal: Does Treatment Affect Perforation Closure?:

Objective: The study goal was to determine whether treatment of the tympanic membrane at the time of ventilation tube (VT) removal affects closure of the perforation. Study Design: We conducted a retrospective chart review and telephone follow-up of children who underwent VT removal from 1995 through 1998. Results: Among 109 patients (162 ears; 58% male), the mean age at VT removal was 6.7 years. Most VTs (59%) were T-tubes, and most (91%) were removed because of prolonged retention (mean 2.3 years). After VT removal, 111 ears (69%) received treatment, most commonly (44%) with 25% trichloroacetic acid (TCA). At the latest follow-up, 151 of the ears (93%) had healed without additional treatment. Treatment failure occurred more frequently in ears not initially treated with TCA (TCA 3% failure, other treatment 13%, no treatment 8%) and in ears with VTs removed because of otorrhea. Conclusions: Most perforations healed. TCA may promote closure, but a large randomized clinical trial is needed to eliminate physician bias. (Otolaryngol Head Neck Surg 2002;126:663-668.)
Bishordeninyl terpene alkaloids and other constituents of Zanthoxylum culantrillo and Z. coriaceum

Abstract A new alkaloid, culantraramine, has been found in Zanthoxylum culantrillo , and the known alkaloid, alfileramine, has been identified from Z. coriaceum . Both alkaloids are members of a new structural type, bishordeninyl terpenes. Z. culantrillo was also found to contain eudesmin, epieudesmin, hordenine, N -methylisocorydine, magnoflorine, candicine, skimmianine, synephrine, tembetarine and a dihydroxy-dimethoxytetrahydroprotoberberine. Isolated from Z. coriaceum were N -methylisocorydine, dihydrochelerythrine, chelerythrine, N -methylcanadine and aegiline, in addition to alfileramine.
The role of bone density in structuring prehistoric salmon bone assemblages

Abstract Archaeologists working in north-western North America often suggest that the low frequency of salmon cranial elements and abundance of vertebrae in prehistoric deposits reflects the cultural use of stored fish. While empirical documentation of salmon storage is certainly important, a variety of noncultural factors, particularly bone density, should be considered in interpreting body part frequencies. Bone densities of representative cranial and postcranial elements from 10 chinook salmon ( Oncorhynchus tshawytscha ) were measured using X-ray absorptiometry. Except for the otolith, most cranial elements have lower densities than postcranial bones. The role of bone density in structuring prehistoric salmon assemblages is explored through comparisons of density measures with element survivorships in three archaeological assemblages with low cranial element survivorship. The scarcity of cranial elements in two of the assemblages is best explained by density-mediated destruction, while cultural processing probably accounts for the dearth of head bones in the third assemblage.
Effects of naltrexone and CCK on estrous behavior and food intake in Syrian hamsters.

Abstract Food deprivation inhibits estrous behavior in several species of rodents, but little is known about the neurotransmitter systems mediating this phenomenon. We determined whether partial blockade of opioid receptors by continuous infusion of naltrexone and/or acute peripheral injection of cholecystokinin (CCK) administration would overcome the suppressive effects of food deprivation on estrous behavior in Syrian hamsters. Contrary to expectation, naltrexone produced a slight suppression of estrous behavior, and systemic CCK administration had no effect. This dose of naltrexone was sufficient to reduce in vivo binding of [ 3 H]naloxone in the brain, and both compounds affected other parameters such as food intake and body weight gain. Thus, the doses of CCK and naltrexone that were used were physiologically effective. These findings suggest that neither peripheral CCK nor opioid systems are likely to play a major role in the suppression of hamster estrous behavior by food deprivation.
Ontogeny of Hepatic and Renal Systemic Clearance Pathways in Infants Part I

Maturation of drug systemic clearance mechanisms during the postnatal period produces dramatic and rapid changes in an infant's capacity to eliminate drugs. A tentative general mathematical model describing the ontogeny of hepatic cytochrome P450 (CYP) enzyme-mediated clearance and renal clearance due to glomerular filtration in the first 6 months of life was elaborated from age-specific in vitro hepatic microsomal activity data (normalised to amount of hepatic microsomal protein) for enzyme-specific probe substrates and in vivo probe substrate data for glomerular filtration (normalised to bodyweight), respectively. The model predicts an age- and clearance pathway-specific Infant Scaling Factor (ISF) for the first 6 months of life. The ISF reflects functional maturation of a specific clearance pathway (normalised to bodyweight) relative to adult values. Therefore, the ISF directly correlates adult clearance values with an infant's capacity to eliminate drugs. Substitution of appropriate model parameter estimates and the age of the infant into the model provides an estimated ISF value, which may then be used to predict the contribution of a particular clearance pathway to total systemic clearance in the infant when adult systemic clearance values are known. The model was tested for its ability to predict infant systemic clearance of drugs whose elimination is principally mediated by a single CYP enzyme or by glomerular filtration. The model performed reasonably well for CYP1A2 and CYP3A4, but poorer predictions were obtained for CYP2D6 and CYP2C because of lack of model complexity and/or inadequate hepatic microsomal activity data to fully describe the maturational process of functional enzyme. For renal clearance due to glomerular filtration, data normalised to bodyweight (kg) showed a limited maturational trend, suggesting that adult renal clearances normalised to bodyweight might reasonably predict infant renal clearances in the first 6 months of life. The model provided reasonable predictions of renal clearance due to glomerular filtration in the infant.
Conditional and post algebra expressions

Boolean expressions of Boolean algebras are logically equivalent to conditional logic expressions; we define and give theorems about equivalences of general conditional expressions; moreover, conditional expressions are properly contained in n-valued Post algebras. Theorems are given regarding equivalences of conditional logic in Post logic.
Failure of shortening and inversion of the perinatal gubernaculum in the cryptorchid long-evans orl rat.

Purpose: Failure of testicular descent occurs in about 65% of spontaneously cryptorchid Long-Evans orl rats. Development of the fetal gubernaculum is dependent on expression of leucine rich G protein coupled receptor (also known as G protein coupled receptor affecting testicular descent) and its ligand, insulin-like 3. We studied testicular descent and mRNA expression of insulin-like 3 and leucine rich G protein coupled receptor in Long-Evans orl and Long-Evans wild-type rats during perinatal development.Materials and Methods: Long-Evans orl and Long-Evans wild-type males obtained at gestational days 18 to 21 and day of birth were preserved in RNAlater® for at least 24 hours. The size and position of the testes, kidneys and gubernacula were determined by microdissection and image analysis. Leucine rich G protein coupled receptor mRNA expression was analyzed in fetal gubernacula (gestational days 18 to 21) using real-time reverse transcriptase polymerase chain reaction with SYBR® Green detection. Insulin-l...
Multiple nucleation pathways near triple points of Ar–Kr mixtures

Cluster partition functions for droplets of Ar–Kr mixtures are evaluated at 90 and 120 K by the inversely restricted sampling (IRS) algorithm. These quantities and series expansion techniques are used within the droplet model to condensation to predict the condensation curve in the neighborhood of a triple point of the Ar–Kr phase diagrams. Using the same series, the free energy surface for droplet growth is examined for supersaturated states of the mixture. For strongly supersaturated states in the neighborhood of the triple point, we find two saddle‐point free energy barriers. It is suggested that these physical circumstances provide a sensitive testing ground for molecular theories of homogeneous nucleation.
Spectroscopic determination of copolymer composition in high isocyanate content polymers

Copolymer compositions high in aliphatic isocyanate content cannot be determined by typical titration methods due to crosslinking during polymer workup. A quantitative method involving ultraviolet analysis of an isocyanate/absorbing amine adduct is presented. Agreement between the ultraviolet (UV) method and elemental analysis, in both composition data and reactivity ratios (r1r2, which are calculated from data obtained by the UV method) delineate a viable method of polymer analysis. Data from Fourier transform infrared (FTIR) analysis of the urea linkage is in good agreement with nitrogen analysis and the UV method, but is sufficiently biased to cause significant differences in r1r2 values. Bias in the infrared analysis may arise from the intra- or intermolecular interaction of CO and NH groups of the urea linkage. Hypochromic effects are observed in UV analysis in noncarbonylic solvents. Hypochromicity varied with copolymer composition and could be related to sequence distributions. The hypochromic effects observed were most pronounced in low amine adduct content polymers where the majority of phenyl chromophores are isolated between MMA units.
Plasma Enhanced Chemical Vapor Deposition Of Dielectric Films: Correlation Of Stress To Film Structure And Plasma Characteristics

Stress in dielectric films, including silicon dioxide, borosilicate glass, and silicon nitride, deposited using Plasma Enhanced Chemical Vapor Deposition have been studied. In each case the total stress was found to be strongly dependent on processing conditions. Deposition rates and film characteristics, such as refractive index, -OH content, (in the case of SiO 2 ), total H content, Si-H and N-HI concentration (in the case of nitride), boron concentration (for BSG), have also been determined as fuctions of processing parameters. In addition, the emission spectra from the plasma itself has been studied. Correlations have been established whereever relevant.
Insulin excess counteracts the effects of HDL on intracellular sterol accumulation in cultured human skin fibroblasts

Both Type 1 (insulin-dependent) and Type 2 (non-insulin-dependent) diabetic individuals are at increased risk of developing ischaemic heart disease. Insulin excess, present in both diabetic groups, may play an important pathophysiologic role in accelerating the atherogenic process. In this study, cultured human skin fibroblasts were incubated with varying concentrations of insulin to test the role of insulin on cell cholesterol homeostasis and on HDL3-mediated removal of excess cholesterol from cells. Insulin excess (1-2-100 nmol/l) resulted in a significant dose-dependent reduction in HDL3-mediated cholesterol efflux from the intracellular unesterified cholesterol pool of cultured human skin fibroblasts. Similar insulin concentrations resulted in impaired HDL-mediated cholesterol efflux from the cell membrane but had no effect on non-HDL-mediated efflux. The effect of insulin on cholesterol esterification and biosynthesis was assessed by14C-oleate labelling. The addition of HDL3 (50 μg) resulted in a significant decrease in14C-labelled cholesterol ester, reflecting a decrease in intracellular unesterified cholesterol, which was partially reversed by the addition of insulin. Insulin had no effect on the incorporation of14C-oleate into unesterified cholesterol. During simultaneous incubation of fibroblasts with LDL and HDL, insulin resulted in an increase in cholesterol esterification and inhibited ability of HDL to promote the decrease in esterification. Thus, we have shown that insulin exess counteracts the beneficial effects of HDL that involve removal of cellular cholesterol and may in part promote atherogenesis by this mechanism
Methane heating rates in outer planet atmospheres

Abstract We have reviewed and expanded the techniques for calculating the heating rates of CH 4 near-i.r. bands (3.3, 2.3 and 1.7 μm) for conditions relevant to the atmospheres of the outer planets. We consider all pressures below 100 mbar and temperatures from 77 to 300 K. We find that using the correlated- k method, the heating rates of the stronger band, 3.3 μm band, at all pressures and the heating rates for the other two bands at pressures below 0.1 mbar can be accurately calculated. We also find that the application of the general random band models which depend on the line listings is not appropriate to these three bands.
Numerical Simulation of Precipitation Development in Supercooled Cumuli-Part I

Abstract A numerical model of supercooled cumuli is developed and discussed. Water substance in the model is idealized to be partitioned into the five phase components; namely, water vapor, liquid cloud water, liquid rainwater, frozen rainwater, and ice crystals. Continuity equations are developed that predict the distribution of water substance among the five phase components. The cloud dynamic framework consists of a simple one-dimensional Lagrangian model that includes the effects of entrainment. The model is able to operate either as a steady-state model or as a spherical vortex model. The results of two case study experiments illustrated that the principle action of ice particles nucleated on sublimation nuclei, or by the freezing of cloud droplets in cumulus clouds containing moderate to heavy amounts of supercooled rainwater, is to promote the freezing of supercooled rainwater. On the other hand, clouds containing small amounts of supercooled rainwater are dynamically insensitive to moderate concen...
PAPER ELECTROPHORETIC STUDIES ON PITUITARY EXTRACTS FROM NORMAL AND THYROIDECTOMTZED RATS1

Paper electrophoretic analysis of saline extracts of rat adenohypophyscal tissue has demonstrated the presence of a protein component which disappeared following thyroidectomy or thiouracil feeding, and was restore:! after thyroxine administration. Since castration and adrenalcctcmy were without effect on this constituent, it is referred to as the “thyroid-labile” component of the adenohypophysis. Extracts of rat anterior pituitary glands which had previously been incubated in vitro in a medium containing lysine-2-C14 were subjected to paper electrophoresis. Radioactivity was detected in the region of the “thyroidlabile” component. Since the amount of radioactivity in this area was the same in extracts from normal and thyroidectomized rats it was concluded that the isotope had been incorporated into minor protein constituents with mobilities similar to that of the “thyroid-labile” component. Both growth hormone and thyrotropin were localized in the region of the “thyroid-labile” component, but differences...
In vivo and in vitro development of α-MSH and ACTH in the embryonic and postnatal rat brain

Abstract The appearance of immunoreactive α-melanotropin (α-MSH) and adrenocorticotropin (ACTH) during development was studied in 3 areas of the rat brain — cerebral hemispheres, midbrain and hindbrain — from embryonic day (ED) 13–14 until day 21 postnatally. The α-MSH content in vivo was always highest in the midbrain; a peak content at birth was followed by a transient decline and a later, higher plateau from postnatal day 7 onwards. The α-MSH content in the cerebral hemispheres rose progressively after birth reaching a peak at day 21. Values in the hindbrain rose at day 3 and changed relatively little thereafter. Aggregating cell cultures of midbrain tissue taken at ED 15–16 showed a gradual increase in α-MSH content over the next 20 days. The α-MSH content of hindbrain cultures remained at constant low levels, while no α-MSH was detectable in cerebral hemisphere cultures. ACTH appeared in vivo earlier than α-MSH and was detectable in embryonic brains at ED 13–14. A transient rise was seen at ED 17–18 and major peaks at birth, day 2 and day 3, in the midbrain, hemispheres and hindbrain, respectively. In vitro, the ACTH content increased in all brain regions during the first 5 days in culture and showed no further change thereafter. Comparisons of the in vivo and in vitro development of α-MSH and ACTH demonstrate that (i) these two peptide systems are independent in respect to their localization and time of appearance; (ii) they undergo maturation both in vivo and in vitro; (iii) epigenetic factors, such as interactions with other neurotransmitter systems may modulate the developmental pattern of these two peptides.
Extended x-ray-absorption fine-structure studies of diamond and graphite

We have recorded the extended x-ray-absorption fine structure (EXAFS) above the carbon K edge for diamond and highly oriented crystalline graphite using 250--800-eV synchrotron radiation. The spectra are used to test phase and amplitude transferability of the C-C EXAFS signal between the two bonding forms of carbon. We find excellent phaseshift transferability with errors in distances less than 0.01 A. Amplitude transferability is worse but better than 20%. Implications of our results for structural determinations of C-C bonds in molecules and solids are discussed.
X-Ray Imaging In The Laser-Fusion Program

Imaging devices which are used or planned for x-ray imaging in the laser-fusion program are discussed. Resolution criteria are explained, and a suggestion is made for using the modulation transfer function as a uniform definition of resolution for these devices.
Computation of equilibrium states and bifurcations using interval analysis : Application to food chain models

Food chains and webs in the environment are highly nonlinear and interdependent systems. When these systems are modeled using simple sets of ordinary differential equations, these models can exhibit very rich and complex mathematical behaviors. We present here a new equation-solving technique for computing all equilibrium states and bifurcations of equilibria in food chain models. The method used is based on interval analysis, in particular an interval-Newton/generalized-bisection algorithm. Unlike the continuation methods often used in this context, the interval method provides a mathematical and computational guarantee that all roots of a nonlinear equation system are located. The technique is demonstrated using three different food chain models, and results of the computations are used to compare the models.
Twenty-Year Follow-Up of Patients With New Perioperative Q Waves After Coronary Artery Bypass Grafting

Perioperative myocardial infarction (MI) is a wellknown complication of coronary artery bypass grafting (CABG),1 with an incidence between 1.3% and 25%.1‐ 4 Although risk factors for perioperative infarction after bypass4,5 have been described, there is no consensus about its long-term clinical significance.1,6 ‐9 Clinically, a new perioperative MI is most often suspected because of the appearance of new Q waves on the postoperative electrocardiogram (ECG). However, it remains unclear whether new postoperative Q waves portend a worse prognosis. If the development of new Q waves after CABG has no impact on prognosis, aggressive evaluation and therapy may not be necessary in uncomplicated cases. To answer this question, we analyzed the effect of new Q waves after CABG on long-term, 20-year survival. Because the development of new Q waves after CABG may result from unmasking of a prior infarction,10 it could be argued that other criteria would help identify only patients with a true perioperative acute MI. We therefore also examined the survival of subgroups of patients with new perioperative Q waves stratified by the presence or absence of concomitant localized STsegment elevation, elevated cardiac enzymes, and/or positive technetium pyrophosphate scans.