cssi/SciSciGPT-SciSciNet huggingface dataset:
Immunologic aberrations in asbestos cement workers: dissociation from asbestosis

Immunoregulatory disorders have been implicated in the pathogenesis of asbestosis. We therefore compared the immunologic status of a well-characterized group of 31 current and former asbestos-cement workers with that of a group of 52 healthy controls, after adjustments had been made for the possible confounding effects of age, race, and smoking. The asbestos workers had significantly decreased percentages and numbers of both B and T lymphocytes in peripheral blood and a paradoxical IgG hypergammaglobulinemia. Analysis of T-lymphocyte subpopulations revealed that total T-cell numbers (OKT3+), helper-inducer T-cell numbers (OKT4+), and suppressor-cytotoxic T cell numbers (OKT8+) were decreased by similar proportions. These decreases were negatively correlated with time elapsing since the end of exposure to asbestos. In both workers and controls, lymphocyte proliferative responses to phytohemagglutinin (PHA) were correlated positively with the number of OKT4+ cells and negatively with age and serum IgG levels. When adjustments had been made for these confounding variables, no differences in PHA responses were noted between workers and controls. No relationship was detected in the workers between any of the immunologic aberrations noted and (1) radiographic category of pneumoconiosis, (2) estimates of cumulative asbestos exposure, or (3) abnormalities of pulmonary function. These data suggest that the immunologic perturbations we have noted in asbestos-exposed individuals are epiphenomena, unrelated to the pathogenesis of asbestosis itself.
Pollen Morphology as an Aid in Determining Relationships among some Widely Separated Old World Species of Linum

Abstract Of the 25 to 30 species comprising the subgenus Linum, four are known to have multi-aperturate pollen. Of these, L. stelleroides of China differs in several ways from the others and it appears that the multiaperturate condition may have arisen independently in that species. Linum hologynum, of southeastern Europe, and L. marginale and L. monogynum, of Australia and New Zealand, are believed, on the basis of similarities in both pollen and floral morphology, to comprise a single related complex of species. If so, they constitute one of the very few examples of close affinities between plants endemic to Europe and to Australia
Delayed effects of epidermal growth factor after extensive small bowel resection.

Abstract Epidermal growth factor (EGF) is produced in the gastrointestinal tract and has been shown to have a transient stimulatory effect on mucosal growth and uptake of glutamine. This study investigated the delayed effects of EGF on mucosal brush-border membrane enzymes and glutamine uptake after extensive small bowel resection. Twenty-four New Zealand White rabbits underwent a 50% to 60% midjejunoileal enterectomy. One group of 12 had a subcutaneous osmotic pump inserted, delivering EGF at 0.3 μg/kg/h for the first 7 postoperative days. The other group of 12 served as controls. Six rabbits from each group were killed at 3 weeks, and the remaining 12 were killed at 6 weeks. Six additional rabbits served as nonsurgical controls. There was a twofold increase in mucosal dry weight at 3 weeks without EGF, and an almost fourfold increase with EGF, over control rabbits. This effect of EGF on the mucosa persisted for 6 weeks. Enzymatic activity per gram of protein in each group of rabbits was similar between the four groups of rabbits, although maltase activity increased approximately fourfold over that of nonoperative control animals. However, enzyme capacity of maltase and aminooligopeptidase (AOP) increased threefold and twofold (respectively) at 3 weeks without EGF, and sixfold and fourfold with EGF. Functional capacity is a measure of the load of nutrients that the intestine can digest and absorb, and therefore the derivable benefit to the animal. Glutamine uptake capacity increased 60% in 3 weeks without EGF, then declined by 6 weeks. However with EGF it increased 200% by 3 weeks, and further increased 400% by 6 weeks over control levels. The authors conclude that EGF markedly increases the functional capacity of the small intestine in rabbits that have undergone extensive small bowel resection; this effect persists for up to 6 weeks after a small initial dosage of EGF.
Phase Behavior in a Ternary Rod/Coil/Solvant System: Poly (γ-Benzyl-α, L-glutamate)/Nylon-6/m- cresol

Abstract Ternary phase diagrams for the system Poly (γ-benzl-α, L-glutamate)/Nylon-6/m-cresol, were determined by optical microscopy at room temperature, for several different molecular weights, The pahse diagrams do not closely resemble those predicated form the athermal theory for rod/random, coil/diluent mixtures, as set forth by Flory. The appearance of a biphasic system occurs at lower concentrations than predicted. It is proposed that this phenomenon might be caused by the different hydrogen bonding characteristeics of the two polymers. The utility of epiflousecene microscopy as a supplement to the usual corssed-polars techniques for structural determiantions is discussed.
A New Species of Chaenusa (Hymenoptera: Braconidae) Reared from Hydrellia pakistanae and Hydrellia Sarahae Laticapsula (Diptera: Ephydridae) Infesting Hydrilla verticillata (Alismatales: Hydrocharitaceae) in India and Pakistan

ABSTRACT Chaenusa glabra Kula, new species from India and Pakistan is described, and sexual dimorphism is reported and discussed. A diagnosis is provided to differentiate it from all other species of Chaenusa Haliday sensu lato. It was reared from Hydrellia pakistanae Deonier and Hydrellia sarahae laticapsula Deonier infesting Hydrilla verticillata (L. f.) Royale during foreign exploration for natural enemies of H. verticillata, and is in quarantine at the Florida Biological Control Laboratory in Gainesville. It is the first species of Chaenusa described from the Oriental Region and the only species of Chaenusa known to attack species of Hydrellia Robineau-Desvoidy infesting plants from a genus other than Potamogeton L.
Positron emission tomography imaging of the serotonin transporter in subjects with a history of alcoholism

Abstract Background Our purpose was to investigate the serotonin transporter (SERT) in various brain regions of alcoholics using positron emission tomography and C-11 McN5652. Method Thirty-two adult subjects were involved, 17 social drinkers as control subjects and 15 subjects who were abstinent or recovering alcoholics. Concomitant psychiatric diseases were ruled out based on DSM-IV criteria. The majority of subjects were men. Radioligand binding in 11 brain areas was expressed as the total distribution volume ( DV ), distribution volume of specific binding ( DV spec ), and distribution volume ratio ( DVR ). The cerebellum was used as reference tissue for calculation of DV spec and DVR . Results In subjects with a history of alcoholism, DV was lower in all brain regions, with significant differences in the midbrain, thalamus, amygdala, pons, cingulate gyrus, frontal cortex, and cerebellum. Additionally, DV spec was lower in all brain regions, but differences were only significant in the midbrain; DVR was lower in nine regions but the differences did not reach statistical significance. Conclusions These studies demonstrate lower binding of [ 11 C](+)McN5652 to the SERT in the brain of abstinent or recovering alcoholics compared with control subjects. Differences in the radioligand distribution volumes are more significant before than after correction for nonspecific binding of the radioligand.
Quality-oriented software architecture

This paper proposes a method to select the software architecture for a family of systems that meets user requirements. The method is based on a set of universally accepted design principles and tactics that aims to establish a systematic correlation between the quality requirements of a system and an architectural style that best implements it. The proposed method can also be a valuable assistant to a novice software engineer in selecting an optimal architectural style because the selection of an appropriate architectural style plays an important role in success or failure of a system.
A Mechanism for Phorbol Ester-Mediated Regulation of the PAF Receptor in Human Neutrophils

Phorbol esters induce rapid downregulation of PAF receptors on human neutrophils. The molecular mechanism responsible for this observation has not been elucidated. In the present study, treatment of neutrophils with PMA (10(-7) M) for 10 min caused a complete loss of PAF receptors from the cell surface as determined by specific radioligand binding. This loss of PAF receptors was associated with an inhibition of a PAF-induced increase in [Ca2+]i. Evidence presented in this study suggests that the rapid loss of PAF binding sites from the neutrophil surface is due to PMA-induced PAF receptor internalization and/or redistribution of cellular PAF receptors. This contention is based upon: (i) disruption of PMA-treated neutrophils exposed latent PAF binding sites, while PAF receptors downregulated following A23187 treatment failed to recover upon cell disruption; (ii) PMA-induced PAF receptor downregulation was not observed in cell homogenate preparations, suggesting that cellular integrity which facilitates receptor internalization or redistribution was required; (iii) cytochalasin B, an agent capable of disrupting microfilaments, attenuated PMA-induced PAF receptor downregulation. This phenomenon was reproduced in human mononuclear cells. Thus, the cellular basis for PMA-induced PAF receptor loss from human neutrophils and mononuclear leukocytes likely involves internalization or cellular redistribution of the PAF receptor.
LH Release in Ovariectomized Dogs in Response to Estrogen Withdrawal and its Facilitation by Progesterone

The effects of various estrogen treatments on the profiles of circulating LH in ovariectomized Beagle bitches were determined in 3 separate studies. In the first study, 13 bitches received 1-4 Silastic tubing (4.7 mm o.d.) implants of estradiol-17 3 providing doses of 0.1-0.8 cm/kg during a 72 h period after which the accumulated treatment dose (0.1-1.2 cm/kg) was removed or reduced. In the second study, 16 bitches received an initial estradiol benzoate (EB) injection of 2 pg/kg and 16 h later received an injection of either EB (2 pg/kg) or oil vehicle. In the third study, bitches received EB injections every 6 h for 30 h (n = 4) or 66 h (n = 10) in increasing doses of 0.4-3.6 or 0.4-13.8 pg/kg, respectively, 4 days after receiving small implants of estradiol-17 l (0.15 cm/kg). Five bitches receiving EB for 66 h received progesterone implants (1.6 cm/kg) 6 h after the last EB injection. Each estrogen treatment depressed LH levels within 8-24 h. Preovulatory-like LH surges were consistently observed 26 ± 2 h following removal of estradiol implants (n = 12) and 36 ± 4 h following a single or final EB injection (n = 25). Distinct increases in LH were seldom observed during continued estrogen treatment and were infrequent and sporadic even in bitches in which estradiol levels were elevated above those observed prior to ovulation in intact bitches. Progesterone administered 6 h after 66 h of EB treatment caused higher, earlier and more synchronous LH peaks than did EB treatment alone. The results suggest that the preovulatory surge release of LH in the bitch may be a response to withdrawal of the negative feedback effect of rising estrogen levels and that this withdrawal effect is facilitated by the preovulatory increase in progesterone.
Ykt6p, a Prenylated SNARE Essential for Endoplasmic Reticulum-Golgi Transport

Vesicular transport between secretory compartments requires specific recognition molecules called SNAREs. Here we report the identification of three putative SNAREs, p14 (Sft1p), p28 (Gos1p), and a detailed characterization of p26 (Ykt6p). All three were originally isolated as interacting partners of the cis Golgi target membrane-associated SNARE Sed5p, when Sec18p (yeast NSF) was inactivated. YKT6 is an essential gene that codes for a novel vesicle-associated SNARE functioning at the endoplasmic reticulum-Golgi transport step in the yeast secretory pathway. Depletion of Ykt6p results in the accumulation of the p1 precursor (endoplasmic reticulum form) of the vacuolar enzyme carboxypeptidase Y and morphological abnormalities consistent with a defect in secretion. Membrane localization of Ykt6p is essential for protein function and is normally mediated by isoprenylation. However, replacement of the isoprenylation motif with a bona fide transmembrane anchor results in a functional protein confirming that membrane localization, but not isoprenylation per se, is required for function. Ykt6p and its homologues are highly conserved from yeast to human as demonstrated by the functional complementation of the loss of Ykt6p by its human counterpart. This is the first example of a human SNARE protein functionally replacing a yeast SNARE. This observation implies that the specific details of the vesicle targeting code, like the genetic code, are conserved in evolution.
Common and Exclusive Agencies and Partial Delegation

Within the context of common agency, the article examines separation and partial delegation. The first entails breaking the multiple-task agency into smaller single-task agencies, whereas the second allows principals to substitute some of their efforts for the agency's. With respect to the first alternative, it is shown that common agency can be sustained against separation by the presence of strong complements. For the second alternative, principals partially delegate their effort and retain the right to influence agency output at a later stage of the game. Although this tends to weaken agency incentives, principals may prefer this version of common agency than one under full delegation and may prefer it to an exclusive one.
Constraint Corrected J-R - Curve and its Application to Fracture Assessment for X80 Pipelines

Single specimen J-R curve testing for X80 pipeline steel was conducted using single edge notched bend (SENB) and single edge notched tension (SENT) specimens with various crack lengths. Test data indicate that the J-R curves for this steel are strongly constraint dependent. To facilitate transferability of experimental J-R curves to those for actual cracked components, this paper develops a constraint corrected J-R curve for X80 steel. A modified J-Q theory that can consider the global bending stress influence is proposed so as to correctly quantify constraint effect on the crack-tip fields and the J-R curves. Results show that the modified J-Q solution can well match numerical crack-tip fields for bending specimens, with Q being a load-independent constraint parameter under large scale yielding. Based on the experimental data and numerical analysis, a constraint corrected J-R curve is formulated as a function of the parameter Q and crack extension Δa for X80 steel. A general procedure to predict J-R curves for actual cracked components is then outlined. Comparison indicates that the predicted J-R curves developed in this paper agree well with the experimental data for both SENB and SENT specimens. To demonstrate its application in failure assessment, the constraint corrected J-R curve for X80 steel is used to determine failure loads for a surface cracked pipeline. Reasonable agreement to available analytic solution is achieved.
Effect of feeding an Aspergillus oryzae extract on milk production and related responses in a commercial dairy herd

Abstract The objective of this study was to examine the effects of an Aspergillus oryzae extract on milk production and composition, rectal temperatures, and rumen metabolites in a commercial dairy herd. Holsteins (110 cows with two or more lactations) in midlactation averaging 140 DIM were used in a 120-d trial from May to August 1991. Treatments were control (no additive) and A. oryzae (3g of culture plus 136g of rice mill by-product daily). Both groups were fed a TMR composed of alfalfa silage, alfalfa hay, corn silage, rolled barley, whole cottonseed, beet pulp, liquid supplement, and a protein-mineral mix. No differences were detected in actual milk or 3.5% FCM production. Mean milk protein (3.12 vs. 3.05%) and SNF percentages (8.63 vs. 8.51%) were higher for the group fed A. oryzae . Rectal temperatures taken weekly between 1300 and 1500h were lower for cows fed A. oryzae (38.7 vs. 38.8°C). Cows supplemented with A. oryzae had lower blood urea N concentrations than control cows (13.4 vs. 18.1 mg%).
Regulation of parathyroid hormone secretion by adenyl cyclase

Summary In a well-studied physiologically functioning in vitro system for the study of parathyroid hormone (PTH) secretion, both theophylline and dibutyryl cyclic adenosine monophate (dAMP) caused significant stimulation of PTH secretion. The quantity of PTH in the medium paralleled the release of cyclic 3′, 5′-AMP (CAMP) from incubated tissues. These studies suggest strongly that adenyl cyclase is the mediator of the known effects of calcium ion on PTH secretion.
Structural analyses of antigen binding similarities and differences between rabbit and human anti-gp120 V3 mAbs.

Background The rabbit is a commonly used animal model to study antibody responses in AIDS vaccine development. However, little is known about the relationship between epitopes recognized by the rabbit and human immune systems. Structural knowledge of antigen-antibody interactions of rabbit and human mAbs will help us understand the similarity of these two immune systems in recognizing HIV antigens, thus provides a guidance in using the rabbit for AIDS vaccine development. Methods Complex structures of anti-V3 mAbs R56 and R20, generated by immunizing a rabbit with JR-FL gp120 using a DNA prime-protein boost regimen, were determined and analyzed in comparison with human mAbs from HIV-1 infected patients against the same V3 immunogenic regions. Results The epitope of R56 is structurally mapped to the Nterminal region of the V3 crown, overlapping with the epitopes recognized by human IGHV5-51 germline antiV3 mAbs. Both R56 and the human mAbs bind the highly conserved V3 residues, consistent with their broad neutralization activities. However, while the human antibodies can bind the whole beta-hairpin of the crown, R56 only binds the N-terminal half of the hairpin. The epitope of R20 is located in the V3 C-terminal region near the two highly conserved glycosylation sites at the V3 base. This epitope overlaps with that of human mAb PGT128. A long beta-hairpin CDR H3 of R20 stands at the center of its antigen-binding site in a manner similar to several potent human mAbs such as 2909, and interacts with the epitope by a beta-sheettype interaction. Conclusion Structural analyses of immunization-generated rabbit antibodies show that they can recognize immunogenic regions of gp120 and mimic the binding modes of human antibodies. However, optimized immunization schemes need be tested in rabbits to produce antibodies with sufficient affinity maturation to recognize Env epitopes as complex as that of human antibodies generated in chronic infected patients.
Transcriptional activation of the enterocyte differentiation marker intestinal alkaline phosphatase is associated with changes in the acetylation state of histone H3 at a specific site within its promoter region in vitro

Enterocyte differentiation is thought to occur through the transcriptional regulation of a small subset of specific genes. A recent growing body of evidence indicates that post-translational modifications of chromatin proteins (histones) play an important role in the control of gene transcription. Previous work has demonstrated that one such modification, histone acetylation, occurs in an in vitro model of enterocyte differentiation, butyrate-treated HT-29 cells. In the present work, we sought to determine if the epigenetic signal of histone acetylation occurs in an identifiable pattern in association with the transcriptional activation of the enterocyte differentiation marker gene intestinal alkaline phosphatase (IAP). HT-29 cells were maintained under standard culture conditions and differentiated with sodium butyrate. The chromatin immunoprecipitation (ChIP) assay was used to compare the acetylation state of histones associated with specific regions of the IAP promoter in the two cell populations (undifferentiated vs. differentiated). Chromatin was extracted from cells and cleaved by sonication or enzymatic digestion to obtain fragments of approximately 200 to 600 base-pairs, as confirmed by polymerase chain reaction using primers designed to amplify the IAP segments of interest. The ChIP assay selects DNA sequences that are associated with acetylated histones by immunoprecipitation. Unbound segments represent DNA sequences whose histones are not acetylated. After immunoprecipitation, sequences were detected by radiolabeled polymerase chain reaction, and the relative intensity of the bands was quantified by densitometry. The relative acetylation state of histones at specific sites was determined by comparing the ratios of bound/unbound segments. We determined that in a segment of the IAP promoter between -378 and -303 base-pairs upstream from the transcriptional start site, the acetylation state of histone H3 increased twofold in the differentiated, IAP expressing cells, whereas that of histone H4 remained essentially constant. Additionally, at a distant site, between -1378 and -1303 base-pairs, the acetylation state of H3 and H4 did not change appreciably between the undifferentiated and differentiated cells. We conclude that butyrate-induced differentiation is associated with specific and localized changes in the histone acetylation state within the IAP promoter. These changes within the endogenous IAP gene may underlie its transcriptional activation in the context of the enterocyte differentiation program.
Gene expression patterns predict exposure to PCBs in developing Xenopus laevis tadpoles

Polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants that pose global ecological and human health problems. Although it is well established that PCBs are associated with a variety of adverse health effects in wildlife and in humans, it is often difficult to determine direct cause-and-effect relationships between exposure and specific health outcomes. In this study, gene expression signatures were used to relate exposure to PCBs with altered physiological responses and/or specific health effects. Real-time PCR was used to measure gene expression levels for 10 genes in Xenopus laevis tadpoles (18 days postfertilization, PF) after acute exposure (2 days) to the PCB mixture Aroclor 1254. Specific gene expression signatures correlated with exposure and were predictive of adverse health effects. Exposure to low levels of Aroclor 1254 (5-50 ppb) significantly increased expression of six genes, independent of any health effects; exposure to midlevel concentrations (300-400 ppb) significantly decreased expression levels of two genes, NGF and beta-actin, prior to the onset of observable health effects; exposure to higher doses (500-700 ppb) significantly decreased NGF and beta-actin expression concomitant with the appearance of gross morphological abnormalities, behavioral deficits, and a statistically significant decrease in survival. This study expands upon our previous work that demonstrated an age-dependent susceptibility to Aroclor 1254 in Xenopus laevis tadpoles and that defined specific gene expression signatures as useful bioindicators of exposure and as predictors of overt or impending health effects.
SickleREMOTE: A two-way text messaging system for pediatric sickle cell disease patients

Sickle cell disease, the most common hemo-globinopathy in the world, affects patient lives from early childhood. Effective care of sickle cell disease requires frequent medical monitoring, such as tracking the frequency, severity, and duration of painful events. Conventional monitoring includes paper- or web-based reporting diaries. These systems require that patients carry forms, which are easily lost, or laptop computers, which are impractical to scale to large populations. Both are prone to sporadic use by older adolescents due to lack of reminders. In this paper, we design and prototype a Sickle cell disease REporting and MOnitoring TElemedicine system (SickleREMOTE), aiming to resolve limitations of conventional monitoring diaries. This monitoring system is configured as automated short message service text (SMS-text) messages that arrive at a mobile phone anywhere on a cellular network. The messages may be reminders to encourage treatment adherence or questionnaires to collect self-assessed clinical data relating to treatment adjustments. Patients respond to the messages using pre-determined templates and a cloud database parses and stores messages automatically. Providers use a web-based interface to view, analyze, and download collected data. SickleREMOTE is developed by Georgia Institute of Technology in conjunction with Children's Healthcare of Atlanta (CHOA). System effectiveness will be evaluated using a trial of 30 adolescents with sickle cell disease and measured by response rate, time to response, error rate, and correspondence with data collected by telephone calls.
Hydrocarbon geochemistry of the Puget Sound region—II. Sedimentary diterpenoid, steroid and triterpenoid hydrocarbons

Cyclic components of the ‘aliphatic’ hydrocarbon mixtures extracted from Puget Sound sediment cores include a suite of C19 and C20 diterpenoid hydrocarbons of which fichtelite. sandaracopimaradiene, and isopimaradiene have been identified. Although apparently also derived from vascular plants, these diterpenoid hydrocarbons have relative abundances distinctly different from the co-existing plant wax n-alkane suite. Five C27, C28 and C29 diasteranes and four C29, C30 and C31 17α(H), 21β(H) hopanes occur in relatively constant proportion as components of a highly weathered fossil hydrocarbon assemblage. These chromatographically resolved cycloalkanes. along with the strongly covarying unresolved complex mixture, have been introduced to Puget Sound sediments from adjacent urban centres at increasing levels over the last 100 yr in the absence of any major oil spill. Naturally-occurring triterpenoid hydrocarbons, including hop-22(29)-ene (diploptene), are also present. A new group of C30 polyenes has been detected which contains compounds apparently structurally related to a co-existing bicyclic C25 diene and to C20 and C25 acyclic multibranched hydrocarbons described in a previous paper (Barrick et al., 1980).
Biology: Vive la différence

Suzanne Alonzo relishes a synthesis of the extraordinary variations among males and females of the same species.
The hyperstoichiometric ZrMn1+xFe1+y−H2 system II: Hysteresis effect

Abstract The absorption pressure-composition isotherms in the temperature range 23–200 °C were determined for the ZrMn 1.22 Fe 1.11 −H 2 and ZrMn 1.11 Fe 1.22 −H 2 systems using a gasometric technique. Marked hysteresis was observed. The pressure P a needed for hydride formation exceeded the decomposition pressure P d by a factor of 5–6 at room temperature. To explain the hysteresis, the strain energies associated with various sites were computed. These results provided a basis for understanding the hydrogen atom occupancy in the ZrMn 2 hydride. Strain energies at room temperature were computed to be 8.7 kJ (mol H 2 ) −1 and 9.1 kJ (mol H 2 ) −1 for the ZrMn 1.22 Fe 1.11 −H 2 and ZrMn 1.11 Fe 1.23 −H 2 systems respectively. These values are in reasonable agreement with the observed freeenergy difference or the enthalpy difference derived from the absorption and desorption pressure-composition isotherms. This analysis makes it appear almost certain that hysteresis is primarily a consequence of strain energy.
Dynamic process modeling with recurrent neural networks

Mathematical models play an important role in control system synthesis. However, due to the inherent nonlinearity, complexity and uncertainty of chemical processes, it is usually difficult to obtain an accurate model for a chemical engineering system. A method of nonlinear static and dynamic process modeling via recurrent neural networks (RNNs) is studied. An RNN model is a set of coupled nonlinear ordinary differential equations in continuous time domain with nonlinear dynamic node characteristics as well as both feed forward and feedback connections. For such networks, each physical input to a system corresponds to exactly one input to the network. The system's dynamics are captured by the internal structure of the network. The structure of RNN models may be more natural and attractive than that of feed forward neural network models, but computation time for training is longer. Simulation results show that RNNs can learn both steady-state relationships and process dynamics of continuous and batch, single-input/single-output and multi-input/multi-output systems in a simple and direct manner. Training of RNNs shows only small degradation in the presence of noise in the training data. Thus, RNNs constitute a feasible alternative to layered feed forward back propagation neural networks in steady-state and dynamic process modelingmore » and model-based control.« less
Managing productivity of health care organizations

Improving the efficiency and reducing the cost of health care is a particularly complex task, DEA can be used to identify real hospital inefficiencies and opportunities for cost reduction that more traditional techniques do not reveal.
A low noise, non-contact capacitive cardiac sensor

The development of sensitive, non-contact electric field sensors to measure weak bioelectric signals will be useful for the development of a number of unobtrusive health sensors. In this paper we summarize our recent work on a number of specific challenges in the development of non-contact ECG sensors. First, we considered the design of a low noise sensor preamplifier. We have adapted circuit designs that incorporate a double feedback loop to cancel the input transistor leakage current while providing stable operation, fast settling time and good low frequency response without the need for ultrahigh value resistors. The measured input referred noise of the preamplifier in the frequency band 0.05–100 Hz is 0.76 µV rms , which is several times lower than existing ECG preamplifiers.
Low-frequency piezoelectric energy harvesting prototype suitable for the MEMS implementation

A low-frequency piezoelectric energy harvester based on impact vibration assembled with a compliant driving beam and two rigid generating beams is presented. The ambient low frequency is up-converted to high resonant frequency by the periodic impact between the driving beam and the generating beams. The advantages of the harvester are: restricting the large displacement of the compliant driving beam, improving power density and being especially suitable for a compact MEMS approach. The 1.53mW average power of the macroscale impact vibration harvester is achieved at 20.1Hz under 0.4g acceleration. The power density is 93.2µW/cm3, which is 6.8 times that of conventional counterpart (13.6µW/cm3). The measured results demonstrate the potential of the device applied to portable and implantable electronics benefited from the MEMS batch-fabrication technology.
An alternative explanation of hypertension associated with 17α-hydroxylase deficiency syndrome.

Abstract The syndrome of 17α-hydroxylase deficiency is due to the inability to synthesize cortisol and is associated with enhanced secretion of both corticosterone and 11-deoxy-corticosterone (DOC). In humans, corticosterone and its 5α-Ring A-reduced metabolites are excreted via the bile into the intestine and transformed by anaerobic bacteria to 21-dehydroxylated products: 11β-OH-progesterone or 11β-OH-(allo)-5α-preganolones (potent inhibitors of 11β-HSD2 and 11β-HSD1 dehydrogenase). Neomycin blocks the formation of these steroid metabolites and can blunt the hypertension in rats induced by either ACTH or corticosterone. 3α,5α-Tetrahydro-corticosterone, 11β-hydroxy-progesterone, and 3α,5α-tetrahydro-11β-hydroxy-progesterone strongly inhibit 11β-HSD2 and 11β-HSD1 dehydrogenase activity; all these compounds are hypertensinogenic when infused in adrenally intact rats. Urine obtained from a patient with 17α-hydroxylase deficiency demonstrated markedly elevated levels of endogenous glycyrrhetinic acid-like factors (GALFs) that inhibit 11β-HSD2 and 11β-HSD1 dehydrogenase activity (>300 times greater, and >400 times greater, respectively, than those in normotensive controls). Thus, in addition to DOC, corticosterone and its 5α-pathway products as well as the 11-oxygenated progesterone derivatives may play a previously unrecognized role in the increased Na+ retention and BP associated with patients with 17α-hydroxylase deficiency.
Neuroendocrine and cytokine profile of chronic mild stress-induced anhedonia

A bidirectional relationship exists between depression and cardiovascular disease. Patients with major depression are more likely to develop cardiac events, and patients with myocardial infarction and heart failure are more likely to develop depression. A feature common to both clinical syndromes is activation of proinflammatory cytokines and stress hormones, including the hypothalamic-pituitary-adrenal axis and the renin-angiotensin-aldosterone system. In the present study we examined the hypothesis that exposure to chronic mild stress (CMS), an experimental model of depression that induces anhedonia in rats, is sufficient to activate the production of proinflammatory cytokines and stress hormones that are detrimental to the heart and vascular system. Four weeks of exposure of male, Sprague-Dawley rats to mild unpredictable environmental stressors resulted in anhedonia which was operationally defined as a reduction in sucrose intake without a concomitant effect on water intake. Humoral assays indicated increased plasma levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), plasma renin activity, aldosterone, and corticosterone in the CMS exposed rats. Tissue TNF-alpha and IL-1beta were increased in the hypothalamus, and TNF-alpha was increased in the pituitary gland. These humoral responses to CMS, associated with anhedonia as an index of depression in the rat, are likely to be associated with neurohumoral mechanisms that may contribute to adverse cardiac events. The findings provide a basis for examining more directly the interactions among the central, endocrine, and immune systems in depression associated with heart disease.
Lessened Effectiveness of Bacteriostatic Agents vs. Tuberculous Infection in Rabbits with Impaired Functional Efficiency

SummarySulfanilamide and P-caproylaminobenzenesulfon-hydroxamide, producing 20 and 60% inhibition of growth, respectively, in broth cultures of the avian tubercle bacillus, exert a comparable degree of restriction on the rate of increase in size of the local lesion produced by subcutaneous injection of this organism, in rabbits with warming times less than 40, but not in rabbits with warming times appreciably longer than 40.
The Role and Contribution of Leukotrienes in Asthma

Learning objectives Reading this article will reinforce the reader's knowledge of the biochemistry and pharmacology of leukotrienes (LTs), including the enzymes and cells involved in their synthesis, the receptors that mediate their biologic effects, and the evidence that cysteinyl leukotrienes (CysLT) may play an important role in asthma. The 5-lipoxygenase inhibitors, 5-lipoxygenase-activating protein antagonists, and Cys LT receptor antagonists are three classes of LTs modulators now in clinical use. The effects of these agents in clinical models of asthma induced by allergens, exercise, and aspirin and in multicenter asthma trials are reviewed. Data sources Key papers published in peer-reviewed journals. Study selection Key papers published in peer-reviewed journals. Conclusions The pharmacology of these new medications and experience in clinical trials suggest that they may play a therapeutic role in the treatment of asthma.
Advantages of the use of intact plant tissues in freeze-fracture electron microscopy.

The use of whole, intact plant tissue for freeze-fracture electron microscopy provides important information that cannot be obtained from the use of isolated biological membranes or of artifical (phospholipid) membrane preparations. This is not to imply that these exminations of such preparations are not useful, since it would be difficult to interpret our observations of intact cells and tissues without the analysis of these model systems. Analysis of intact tissue and cells reveals the relative densities of membrane proteins of the different membranes within a cell; the three-dimensional organization of various organelles, especially the endoplasmic reticulum; changes in intramembranous particle (IMP) distribution due to stress or injury; and, in conjunction with the use of filipin, membrane sterol content and relative distribution. It is our intention that this survey of freeze-fracture images of intact plant tissues will illustrate the uniqueness of the information gained from an analysis of whole plant tissues compared to isolated membrane fractions.
Synthesis of spacer-equipped phosphorylated di-, tri- and tetrasaccharide fragments of the O-specific polysaccharide of Vibrio cholerae O139.

Abstract The synthesis of oligosaccharide fragments of the O-specific polysaccharide of Vibrio cholerae O139 containing a 4,6-cyclic phosphate galactose residue linked to GlcNAc is described. 8-Azido-3,6-dioxaoctyl 2,3,4,6-tetra- O -acetyl-β- d -galactopyranosyl-(1→3)-2-acetamido-4,6- O -benzylidene-2-deoxy-β- d -glucopyranoside, obtained by condensation of 2,3,4,6-tetra- O -acetyl-α- d -galactopyranosyl bromide and 8-azido-3,6-dioxaoctyl 2-acetamido-4,6- O -benzylidene-2-deoxy-β- d -glucopyranoside, was converted to 8-azido-3,6-dioxaoctyl 3- O -benzyl-β- d -galactopyranosyl-(1→3)-2-acetamido-6- O -benzyl-2-deoxy-β- d -glucopyranoside ( 6 ) by reductive opening of the acetal, followed by deacetylation and selective benzylation. Phosphorylation of 6 furnished two isomeric 4,6-cyclic 2,2,2-trichloroethyl phosphates. Glycosylation of the ( S )-phosphate with 2,4-di- O -benzyl-3,6-dideoxy-α- l - xylo -hexopyranosyl bromide under halide-assisted conditions gave the desired tetrasaccharide, together with a trisaccharide. Global deprotection and reduction of the azide to an amine was effected by catalytic hydrogenation/hydrogenolysis to give the deprotected tetrasaccharide, which is functionalized for conjugation.
Silencers and domains of generalized repression

Gene expression can be affected by the chromosomal position of the gene. An example of this position effect is silencing of the HML and HMR mating-type loci of Saccharomyces cerevisiae. An in vitro assay revealed that silencing induced a transcription-independent general occlusion of the DNA at HMR from sequence-specific interactions of proteins with DNA. The minimum boundaries of the silenced chromatin structure were determined, as were the contributions of the E and I silencers to the size of the silenced domain. Examination of endonuclease-sensitive sites provided evidence that neither the integrity of the chromosomal duplex nor covalent linkage of the silencers to HMR was important for maintenance of the silenced structure in vitro.
Estuarine Phytoplankton Responses to Hurricanes and Tropical Storms with Different Characteristics (Trajectory, Rainfall, Winds)

We examined the short-term (<1 month post-storm) impact of storms [Tropical Storm (TS) Helene in 2000, Hurricane (H) Isabel in 2003, H Alex, Tropical Depression (TD) Bonnie and TS Charley in 2004] varying in their trajectory, wind and rainfall characteristics, on water column structure, nutrients, and phytoplankton biomass in North Carolina’s Neuse R. Estuary (NRE). Data are presented from two sampling programs, ModMon (biweekly) and FerryMon (measurements made every 3 min daily). Helene’s winds mixed the previously stratified water column, delivering sediment-bound nutrients to the euphotic zone, and localized freshwater input from Helene was also evident. Mean chlorophyll a concentrations in the mesohaline portion of the NRE, where N was strongly limiting before the storm (molar DIN:DIP < 1), more than doubled after the storm. Unlike with Helene, the water column was well mixed before passage of Isabel, and nutrient concentrations were high. As a result, minimal impact on phytoplankton biomass was detected despite Isabel’s high winds and significant freshwater input. In fact, conditions became less favorable for phytoplankton growth after the storm. Alex was fast moving and relatively small, but its winds were sufficient to mix the water column. Although data from ModMon suggest that chlorophyll a was only slightly higher after passage of Alex, FerryMon detected an ephemeral bloom that was missed by ModMon. Overall, these results suggest that relatively small tropical storms and hurricanes can lead to significant increases in phytoplankton biomass. However, the phytoplankton response depends on both the characteristics of a particular storm and the physical–chemical conditions of the water column before storm passage. Finally, the ephemeral bloom that developed as a result of Alex, the strong response of phytoplankton in the mesohaline portion of the estuary to nutrient inputs, and their patchiness on several other occasions suggests that storms may create “hot spots” for trophic transfer and biogeochemical dynamics in estuaries. Adaptive sampling is necessary to capture these features and to fully understand the impact of perturbations such as storms on estuarine ecosystem functioning.
A Ca2+-Dependent Global Conformational Change in the 3D Structure of Phosphorylase Kinase Obtained from Electron Microscopy

Phosphorylase kinase (PhK), a Ca(2+)-dependent regulatory enzyme of the glycogenolytic cascade in skeletal muscle, is a 1.3 MDa hexadecameric oligomer comprising four copies of four distinct subunits, termed alpha, beta, gamma, and delta, the last being endogenous calmodulin. The structures of both nonactivated and Ca(2+)-activated PhK were determined to elucidate Ca(2+)-induced structural changes associated with PhK's activation. Reconstructions of both conformers of the kinase, each including over 11,000 particles, yielded bridged, bilobal structures with resolutions estimated by Fourier shell correlation at 24 A using a 0.5 correlation cutoff, or at 18 A by the 3sigma (corrected for D(2) symmetry) threshold curve. Extensive Ca(2+)-induced structural changes were observed in regions encompassing both the lobes and bridges, consistent with changes in subunit interactions upon activation. The relative placement of the alpha, beta, gamma, and delta subunits in the nonactivated three-dimensional structure, relying upon previous two-dimensional localizations, is in agreement with the known effects of Ca(2+) on subunit conformations and interactions in the PhK complex.
Crystal Structure of 1-nitro-2-phenylcycloprop-2-enecarbonitrile

The synthesis and x-ray crystal structure of 1 -nitro-2-phenylcycloprop-2-enecarbonitrile [1] is reported. The C-NO2 bond length in1 is similar to but slightly shorter than that reported for 1, 2-diphenyl-3-nitrocyclopropene (2). Unlike2, 1 shows no tendency to ionize to the corresponding cyclopropenium ion in solution. This result is further supported by ab initio calculations.
Efficacy of a Nonpathogenic Acidovorax citrulli Strain as a Biocontrol Seed Treatment for Bacterial Fruit Blotch of Cucurbits.

Johnson, K. L., Minsavage, G. V., Le, T., Jones, J. B., and Walcott, R. R. 2011. Efficacy of a nonpathogenic Acidovorax citrulli strain as a biocontrol seed treatment for bacterial fruit blotch of cucurbits. Plant Dis. 95:697-704. Bacterial fruit blotch (BFB), caused by the seedborne, gram-negative bacterium Acidovorax citrulli, is a serious threat to cucurbit seed and fruit production worldwide. Because of the lack of effective management strategies, we investigated the efficacy of a nonpathogenic A. citrulli strain as a biological control seed treatment for BFB. For this study, we generated a type III secretion system mutant of A. citrulli, AAC00-1ΔhrcC, that was nonpathogenic on watermelon but retained its ability to colonize germinating watermelon seed. With watermelon seed naturally infested with A. citrulli, AAC00-1ΔhrcC reduced BFB seedling transmission by 81.8% relative to control seed. In comparison, another A. citrulli antagonist, A. avenae strain AAA 99-2, reduced BFB seedling transmission by 74.6% for seed samples from the same lot. Additionally, when female watermelon blossoms were protected with AAC00-1ΔhrcC and subsequently challenged with AAC00-1, the resulting seedlots displayed 8% BFB seedling transmission. This was not significantly different than seed from blossoms protected with AAA 99-2 (4%) but significantly less than those from blossoms protected with 0.1 M phosphate-buffered saline (36%). These results suggest that nonpathogenic A. citrulli has potential as a biological control seed treatment component in a comprehensive BFB management program. Bacterial fruit blotch (BFB) of cucurbits, caused by the gramnegative bacterium Acidovorax citrulli (33) (formerly A. avenae subsp. citrulli; 42), poses a significant threat to cucurbit seed and fruit production worldwide (32). BFB was reported in commercial watermelon fields in Florida in 1989, and frequent outbreaks caused significant economic losses across the southeastern United States in the early 1990s (35). At present, the disease is a sporadic threat to cucurbit producers worldwide (4,26,29), because an outbreak can lead to 100% yield loss under ideal environmental conditions.
Energy embedding of trypsin inhibitor.

Synopsis Energy embedding has been shown recently to be a useful extension of the distance geometry approach to conformational calculations in the case of very small molecules and simple energy functions. This paper tests theability of energy embedding to locate low energy conformations satisfying both weak and strong geometric constraints when the molecule is the small protein, bovine pancreatic trypsin inhibitor, and the energy function is the complicated OobatakeCrippen residue-residue potential. Using the potential function alone, the algorithm reaches a structure with energy lower than that of the native conformation, but with little resemblance to it. Aided by numerous geometric constraints, such as preformed secondary structure segments, the algorithm again finds a local minimum with energy better than that of the native, and with only 3.3 21 rms deviation from it. This is significantly closer to the native value than can be obtained using standard distance geometry and the geometric constraints alone. Thus, energy embedding using the Oobatake-Crippen potential function is a significant help in finding native conformations of proteins. However, additional trials on a hairpin bend fragment of trypsin inhibitor demonstrate the potential’s shortcomings in encouraging proper secondary structure.
Temporally and spatially resolved spectroscopy of laser-induced plasma from a droplet.

A new diagnostic technique provides temporally and spatially resolved information at two settable wavelengths within the plasma-emission profile of a single transparent water droplet (40 μm in radius and containing 4 M NaCl) irradiated by a high-intensity laser beam. Data from this technique are compared with those from conventional techniques that separately provide time-averaged spatially resolved spectra or spatially averaged temporally resolved spectra of the plasma emission from droplets.