gebhart/patrepeval huggingface dataset:
V-groove side-pumped 1.5-/spl mu/m fiber amplifier (1996)

Summary form only given. A low-cost, efficient fiber amplifier based on imbedded v-groove side-pumping of a double-cladding fiber was demonstrated. Side-pumping of double-cladding active fibers has the following advantages i) fiber ends are unobstructed and can be directly spliced to other fibers, ii) multiple v-grooves can be used to inject pump power at many points along the fiber, iii) no WDM couplers are required. These advantages yield a compact and efficient amplifier configuration and more than tenfold cost reduction. Improvements in the coupling efficiency and fiber slope efficiency, as well as the use of multiple v-grooves are expected to yield output powers well above the 154 mW demonstrated here.
Characterization of the Escherichia coli transcription factor .sigma.70: localization of a region involved in the interaction with core RNA polymerase (1989)

A set of internal deletions and frame-shift mutations was made in the structural gene for the major sigma factor of Escherichia coli RNA polymerase (sigma 70). The truncated proteins from these various mutants were examined to determine if they retained the ability to bind core RNA polymerase. Two assays were used to determine core-binding activity. Gel filtration was used to separate free sigma 70 from sigma 70 bound to core polymerase. Immunoprecipitation of polymerase using an anti-alpha-subunit monoclonal antibody was also used to determine if the various truncated proteins were bound to core. Results from these experiments indicate core-binding activity is retained when large portions of the sigma 70 protein are deleted. Deletion of a region in the central portion of the protein caused a large decrease in core-binding activity. The results suggest that the region spanning amino acids 361-390 is important for efficient core-binding activity. Sequence comparison of various sigma factors shows highly conserved amino acids in this region. A synthetic peptide having the sequence of amino acids 361-390 was synthesized and examined for the ability to bind core RNA polymerase.
Phytate ( myo -Inositol Hexaphosphate) and Risk Factors for Osteoporosis (2008)

Several risk factors seem to play a role in the development of osteoporosis. Phytate is a naturally occurring compound that is ingested in significant amounts by those with diets rich in whole grains. The aim of this study was to evaluate phytate consumption as a risk factor in osteoporosis. In a first group of 1,473 volunteer subjects, bone mineral density was determined by means of dual radiological absorptiometry in the calcaneus. In a second group of 433 subjects (used for validation of results obtained for the first group), bone mineral density was determined in the lumbar column and the neck of the femur. Subjects were individually interviewed about selected osteoporosis risk factors. Dietary information related to phytate consumption was acquired by questionnaires conducted on two different occasions, the second between 2 and 3 months after performing the first one. One-way analysis of variance or Student's t test was used to determine statistical differences between groups. Bone mineral density increased with increasing phytate consumption. Multivariate linear regression analysis indicated that body weight and low phytate consumption were the risk factors with greatest influence on bone mineral density. Phytate consumption had a protective effect against osteoporosis, suggesting that low phytate consumption should be considered an osteoporosis risk factor.
Ferdinando Fasce, Una famiglia a stelle e strisce: grande guerra e cultura d'impressa in America. Bologna: Il Mulino, 1993. 251 pp. L 32,000 paper. (1998)

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Multivalent structure of galectin-1-nanogold complex serves as potential therapeutics for rheumatoid arthritis by enhancing receptor clustering (2012)

Cellular behaviour is controlled by numerous processes, including intracellular signalling pathways that are triggered by the binding of ligands with cell surface receptors. Multivalent ligands have multiple copies of a recognition element that binds to receptors and influences downstream signals. Nanoparticle-ligand complexes may form multivalent structures to crosslink receptors with high avidity and specificity. After conjugation onto gold nanoparticles, galectin-1 (Au-Gal1) bound with higher affinity to Jurkat cells to promote CD45 clustering and inhibition of its phosphatase activity, resulting in enhancement of apoptosis via caspase-dependent pathways. Au-Gal1 injected intra-articularly into rats with collagen-induced arthritis (CIA) promoted apoptosis of CD4+ T cells and reduced pro-inflammatory cytokine levels in the ankle joints as well as ameliorated clinical symptoms of arthritis. These observed therapeutic effects indicate that the multivalent structure of nanoparticle-ligands can regulate the distribution of cell surface receptors and subsequent intracellular signalling, and this may provide new insights into nanoparticle applications.
Response of human chondrocytes on polymer surfaces with different micropore sizes for tissue‐engineered cartilage (2004)

Abstract Response of chondrocytes on polymer surfaces is important for applications of tissue‐engineered cartilage, and tissue engineering contains the interaction of cells on material surfaces. We examined the behavior of human chondrocytes cultured on polycarbonate (PC) membranes with different micropore sizes (0.2–8.0 μm in diameter). The adhesion and proliferation of chondrocytes were evaluated by measuring the number of attached cells after 1, 2, and 4 days of culture and morphological observations. It seems that the cell adhesion and proliferation were progressively inhibited, as the PC membranes had micropores with increasing size, probably due to surface discontinuities produced by track‐etched pores. On the PC membrane with smaller micropore sizes, the cells seemed to override these surface discontinuities. Phenotype of chondrocyte was assessed by Safranin‐O staining for anionic sulfated proteoglycans. Chondrocytes on the 8.0 μm‐diameter membrane surface proliferated, on 8 days, formed morphology of round shape, and expressed proteoglycans, because of limitation of spreading by the track‐etched micropores. They maintained their phenotype under conditions that support a round cell shape on the large pore diameter substrate, whereas chondrocyte phenotypes lost on the small pore diameter membranes. In conclusion, this study demonstrated that micropore sizes as well as pore‐to‐pore distance play an important role for adhesion, proliferation, and phenotype of human articular chondrocytes. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2784–2790, 2004
Irreversible Electroporation: A New Ablation Modality — Clinical Implications (2007)

Irreversible electroporation (IRE) is a new tissue ablation technique in which micro to millisecond electrical pulses are delivered to undesirable tissue to produce cell necrosis through irreversible cell membrane permeabilization. IRE affects only the cell membrane and no other structure in the tissue. The goal of the study is to test our IRE tissue ablation methodology in the pig liver, provide first experience results on long term histopathology of IRE ablated tissue, and discuss the clinical implications of the findings. The study consists of: a) designing an IRE ablation protocol through a mathematical analysis of the electrical field during electroporation; b) using ultrasound to position the electroporation electrodes in the predetermined locations and subsequently to monitor the process; c) applying the predetermined electroporation pulses; d) performing histopathology on the treated samples for up to two weeks after the procedure; and e) correlating the mathematical analysis, ultrasound data, and histology. We observed that electroporation affects tissue in a way that can be imaged in real time with ultrasound, which should facilitate real time control of electroporation during clinical applications. We observed cell ablation to the margin of the treated lesion with several cells thickness resolution. There appears to be complete ablation to the margin of blood vessels without compromising the functionality of the blood vessels, which suggests that IRE is a promising method for treatment of tumors near blood vessels (a significant challenge with current ablation methods). Consistent with the mechanism of action of IRE on the cell membrane only, we show that the structure of bile ducts, blood vessels, and connective tissues remains intact with IRE. We report extremely rapid resolution of lesions, within two weeks, which is consistent with retention of vasculature. We also document tentative evidence for an immunological response to the ablated tissue. Last, we show that mathematical predictions with the Laplace equation can be used in treatment planning. The IRE tissue ablation technique, as characterized in this report, may become an important new tool in the surgeon armamentarium.
Novel and diagnostically applicable information from optical waveform analysis of blood coagulation in disseminated intravascular coagulation (1997)

Transmittance waveform is the term applied to the optical profile generated from the process of clot formation on standard coagulation tests run on the MDA-180, a new-generation automated coagulation analyser. In patients with disseminated intravascular coagulation, a characteristically abnormal 'biphasic change' is seen on both the activated partial thromboplastin time and thrombin time waveforms. Increasing steepness of the initial slope on the waveform correlates with clinical deterioration and fulminant progression. Although the mechanism underlying the biphasic appearance remains to be elucidated, its identification provides the diagnostic laboratory with a simple, rapid and robust assay for disseminated intravascular coagulation that can help the clinician with urgent and appropriate therapeutic interventions.
Dimerization: An Emerging Concept for G Protein–Coupled Receptor Ontogeny and Function (2002)

In the last four to five years, the view that G protein-coupled receptors (GPCRs) function as monomeric proteins has been challenged by numerous studies, which suggests that GPCRs exist as dimers or even higher-structure oligomers. Recently, biophysical methods based on luminescence and fluorescence energy transfer have confirmed the existence of such oligomeric complexes in living cells. Although no consensus exists on the role of receptor dimerization, converging evidence suggests potential roles in various aspects of receptor biogenesis and function. In several cases, receptors appear to fold as constitutive dimers early after biosynthesis, whereas ligand-promoted dimerization at the cell surface has been proposed for others. The reports of heterodimerization between receptor subtypes suggest a potential level of receptor complexity that could account for previously unexpected pharmacological diversities. In addition to fundamentally changing our views on the structure and activation processes of GPCRs, the concept of homo- and heterodimerization could have dramatic impacts on drug development and screening.
Ordered cosmid library and high‐resolution physical—genetic map of Helicobacter pylori strain NCTC11638 (1994)

Helicobacter pylori is a Gram-negative bacterium that infects the human gastric mucosa, causes gastritis and contributes to the development of peptic ulcers and gastric cancer. To facilitate molecular genetic analysis of this pathogen, we constructed a approximately 20-fold redundant cosmid library and physical/genetic map of strain NCTC11638. Genomic DNA fragments were cloned into the cosmid vector Lorist6, and clones were ordered by hybridization with several types of probes: (i) ends of cloned DNAs; (ii) chromosomal Notl digest fragments; (iii) cosmids containing Notl sites; and (iv) specific genes. Seven hundred and fifty-one cosmids were mapped to one of three contigs covering > 90% of the chromosome, and are represented by a 68-cosmid miniset. The order of cosmids was confirmed and extents of overlap among them were estimated by restriction analysis. All currently known H. pylori genes were mapped, including those for a cytotoxin (vacA), cytotoxin-associated protein (cagA), urease and regulatory functions (ureAb, ureD and ureH), catalase (katA), major and minor flagellins (flaA and flaB), heat-shock (stress) and chaperone proteins (dnaK, htA, hspB (groEL)), prokaryotic ferritin (pfr), an adhesin subunit (hpaA), a surface protein (26 kDa), and 16S and 23S ribosomal RNAs (two genes each). The orientations of eight genes or clusters were determined, and two repetitive sequences were also found. The gene order and rRNA gene copy number determined here differed from that reported for an unrelated strain, which suggests considerable flexibility in H. pylori genome organization.
Ureaplasma urealyticum intrauterine infection: role in prematurity and disease in newborns (1993)

Ureaplasma urealyticum, a common commensal of the urogenital tract of sexually mature humans, is gaining recognition as an important opportunistic pathogen during pregnancy. While its etiologic significance in many aspects of adverse pregnancy remains controversial, recent evidence indicates that U. urealyticum in the absence of other organisms is a cause of chorioamnionitis. Furthermore, ureaplasmal infection of the chorioamnion is significantly associated with premature spontaneous labor and delivery. In at least some cases, it appears to be causal. Present evidence indicates that U. urealyticum is a cause of septicemia, meningitis, and pneumonia in newborn infants, particularly those born prematurely. There is strong but not definitive evidence that ureaplasmal infection of the lower respiratory tract can lead to development of chronic lung disease in very low-birth-weight infants. Although risk factors for colonization of the lower genitourinary tract have been identified, little information is available concerning risk factors for intrauterine infection and host immune responses to invasive infection. Recent establishment of animal models of respiratory and central nervous system diseases should provide an opportunity to evaluate risk factors, pathogenic mechanisms, and operative immune mechanisms. However, the most critical need is additional information concerning indications for diagnosis and treatment as well as efficacy of treatment.
Down-regulation of prostate-specific antigen expression by finasteride through inhibition of complex formation between androgen receptor and steroid receptor-binding consensus in the promoter of the PSA gene in LNCaP cells. (1997)

As a specific competitive inhibitor of 5alpha-reductase, an intracellular enzyme that converts testosterone to dihydrotestosterone, finasteride is being extensively used for the treatment of benign prostatic hyperplasia and in experimental settings for prostate cancer. In this study, we showed that finasteride markedly inhibited prostate-specific antigen (PSA) secretion and expression. The promoter of the PSA gene contains several well-known cis-regulatory elements. Among them, steroid receptor-binding consensus (SRBC) has been identified as a functional androgen-responsive element. Our previous study showed that PSA was not only present in conditioned medium of the PSA-positive LNCaP cells but was also detectable in small amounts in PSA-negative cell lines, PC-3 and DU-145 (L. G. Wang et al., Oncol. Rep., 3: 911-917, 1996). A strong correlation between binding of nuclear factors to SRBC and the level of PSA present in the conditioned medium and cell extracts was found in these three cell lines, whereas no such correlation with binding was obtained using Sp1 oligonucleotide as a probe. Binding of LNCaP cell nuclear proteins to SRBC was diminished when the cells were exposed to 25 microM finasteride, at which concentration 50% of both PSA mRNA and protein were inhibited. As a major component of DNA-protein complexes, the level of androgen receptor was dramatically decreased in the cells treated with finasteride. Our data indicate that inhibition of complex formation between SRBC and nuclear proteins due to the remarkable decrease in the level of androgen receptor plays a key role in the down-regulation of PSA gene expression by finasteride in LNCaP cells.
Suspension Culture of Mammalian Cells (2018)

Mammalian cell suspension culture systems are being used increasingly in the biotechnology industry. This is due to their many advantages including simplicity and homogeneity of culture. Suspension systems are very adaptable (e.g., for microcarrier, microencapsulation, or other methods of culture). Their engineering is thoroughly understood and standardized at large scale, and automation and cleaning procedures are well established. Suspension systems offer the possibility of quick implementation of production protocols due to their ability to be scaled easily once the basic culture parameters are understood. The only main disadvantage of the suspension culture systems to date is their inapplicability for the production of human vaccines from either primary cell lines or from normal human diploid cell lines (Hayflick et al., 1987 and references therein). One of the great advantages of suspension culture is the opportunity it provides to study interactions of metabolic and production phenomena in chemostat or turbidostat steady-state systems. Furthermore, in suspension culture systems from which cell number and cell mass measurements are easy to obtain, rigorous and quantitative estimations of the effects of growth conditions or perturbations of metabolic homeostasis can be made. Such studies can speed up the development of optimal processes. With our increasing understanding of factors influencing expression in mammalian cells (Cohen and Levinson, 1988; Santoro et al., 1988) and the direct application of new methods in suspension culture (Rhodes and Birch, 1988), its usefulness and importance is likely to increase in the future. In this chapter, we have described some of the potential uses of the various suspension culture systems and have covered most of the established technology and literature. Due to the rapid developments and needs in the biotechnology industry and the versatility of suspension culture systems, it is probable that many more variations on this theme will evolve in the near future at both the pilot and production scales.
Interleukin‐13 selectively induces monocyte chemoattractant protein‐1 synthesis and secretion by human endothelial cells. Involvement of IL‐4Rα and Stat6 phosphorylation (1997)

Chemokines secreted by endothelium have been demonstrated to promote leucocyte recruitment to sites of inflammation. In the present study we investigated the effect of the T lymphocyte-secreted cytokine interleukin (IL)-13 on endothelial expression of chemokines. Employing in situ hybridization and enzyme-linked immunosorbent assay (ELISA) techniques we demonstrate that IL-13, which shares many of its activities with IL-4, selectively induces expression of the C-C chemokine monocyte chemoattractant protein (MCP)-1 in human umbilical vein endothelial cells (HUVEC). However, it fails to up-regulate other C-C and C-X-C chemokines potentially inducible in endothelium such as RANTES (regulated on activation, normal T expressed and secreted), gro-alpha, or IL-8. IL-13 dose-dependently induces monocyte chemotactic activity by HUVEC which can be efficiently blocked by neutralizing antisera against MCP-1. In contrast to the synergistic effect of IL-13 and tumour necrosis factor-alpha (TNF-alpha) on endothelial vascular cell adhesion molecule-1 (VCAM-1) surface expression, TNF-alpha-induced secretion of MCP-1 is not augmented by IL-13. Studying the signalling pathway activated by IL-13 it is demonstrated that a neutralizing monoclonal antibody (mAb) to the 140,000 MW component of the IL-4 receptor (IL-4R alpha) inhibits the effect of IL-13. Immunoprecipitation studies reveal that endothelial IL-4R alpha is rapidly tyrosine phosphorylated upon treatment with IL-13 and IL-4. We furthermore show that both cytokines activate the signal transducer and activator of transcription (Stat) protein-6 in endothelial cells. Our data suggest that IL-13 partly utilizes components of the IL-4 receptor signalling pathway for induction of endothelial MCP-1 expression to facilitate recruitment of blood leucocytes.
Growth of Streptococcus pneumoniae on Human Glycoconjugates Is Dependent upon the Sequential Activity of Bacterial Exoglycosidases (2007)

In the human host, Streptococcus pneumoniae encounters a variety of glycoconjugates, including mucin, host defense molecules, and glycans associated with the epithelial surface. S. pneumoniae is known to encode a number of glycosidases that may modify these glycoconjugates in vivo. Three exoglycosidases, a neuraminidase (NanA), beta-galactosidase (BgaA), and N-acetylglucosaminidase (StrH), have been previously demonstrated to sequentially deglycosylate N-linked glycans on host defense molecules, which coat the pneumococcal surface in vivo. This cleavage is proposed to alter the clearance function of these molecules, allowing pneumococci to persist in the airway. However, we propose that the exoglycosidase-dependent liberation of monosaccharides from these glycoconjugates in close proximity to the pneumococcal surface provides S. pneumoniae with a convenient source of fermentable carbohydrate in vivo. In this study, we demonstrate that S. pneumoniae is able to utilize complex N-linked human glycoconjugates as a sole source of carbon to sustain growth and that efficient growth is dependent upon the sequential deglycosylation of the glycoconjugate substrate by pneumococcal exoglycosidases. In addition to demonstrating a role for NanA, BgaA, and StrH, we have identified a function for the second pneumococcal neuraminidase, NanB, in the deglycosylation of host glycoconjugates and have demonstrated that NanB activity can partially compensate for the loss or dysfunction of NanA. To date, all known functions of pneumococcal neuraminidase have been attributed to NanA. Thus, this study describes the first proposed role for NanB by which it may contribute to S. pneumoniae colonization and pathogenesis.
Breaking Point of Two Breath Holds Separated by a Single Inspiration (1957)

Alveolar gas tensions were measured during six trials for each of three men at normal resting level, at the end of a maximum inspiration, at the breaking point of a first breath hold, at the end of a single gasp and at the breaking point of a second breath hold. The volume of the inspirations preceding each breath hold, as well as the breath holding times, was also measured. The first breath holding time was substantially longer than the second. When Gray's chemical ventilation equation was used, the equivalent ventilation ratio at the first breaking point was significantly lower than that of the second breaking point. Other factors in addition to the chemical stimuli may affect the breaking point of breath holding and the longer time of the first breath hold may allow these additional factors to lower tolerance to chemical stimuli at the first breaking point. Submitted on January 18, 1957