julilili42/papers huggingface dataset:
Estimation of the basic reproduction number of measles during an outbreak in a partially vaccinated population
2000-04-01

From March to July 1996 a measles outbreak occurred in northern Luxembourg with 110 reported cases centered around two primary schools (85 cases) and the surrounding community (25 cases). Eighty four suspected cases were confirmed serologically. Vaccine coverage was estimated from questionnaire-based surveys at the two primary schools to be 70 and 76%, respectively. Vaccine efficacy during the outbreak was estimated to be 94.6% [95% confidence interval (CI) 90·4–97·0]. Using the information from the school surveys, we obtained estimates of the basic reproduction number of measles of 7·7 (95% CI 4·4–11·0) and 6·2 (95% CI 3·5–8·9), respectively. Assuming a 95% vaccine efficacy, these estimates correspond to minimal vaccine coverages of 91·6% (95% CI 81·4–95·7) and 88·3% (95% CI 75·5–93·4) which would have been necessary to minimize the chances of a major outbreak occurring. We can confirm that major outbreaks in similar school settings can only be prevented if vaccination coverage exceeds 90%.
Agr‐independent regulation of fibronectin‐binding protein(s) by the regulatory locus sar in Staphylococcus aureus
2000-04-01

Fibronectin‐binding proteins (FnBPs) are thought to be important for the attachment of Staphylococcus aureus during infection. The regulation of the genes fnb A and fnb B by the global regulatory loci sar and agr was examined using site‐specific regulatory mutants of S. aureus strain Newman. The results from binding assays using both aqueous and solid‐phase fibronectin as well as ligand blotting with biotinylated fibronectin showed that the expression of FnBPA is enhanced in the agr mutant but inhibited in the sar mutant and the sar – agr double mutant. The same regulatory pattern was observed in Northern blot analysis using fnb A‐specific probes. The introduction of sar on a multicopy plasmid increased the already enhanced fnb A transcription of the agr mutant. FnBPB was not detectable by ligand blotting and the fnb B promoter activity in promoter fusion assays was not affected by either sar or agr . The sequence encompassing ORF3 located upstream of sar A was found to be essential for the activation of fnb A transcription. We hypothesize that this sequence may modulate SarA expression and/or activity on the post‐transcriptional level. Gel shift assays demonstrated that SarA binds to the fnbA promoter fragments, probably as a dimer. DNase I footprinting assays with SarA revealed a protected area of 102 bp upstream of fnb A.
Identification of a New Repetitive Element in Staphylococcus aureus
2000-04-01

ABSTRACT The Staphylococcus aureus repeat (STAR) element is a sequence identified in two intergenic regions in S. aureus . The element is found in 13 to 21 copies in individual S. aureus strains, and elements in the homologous intergenic location are variable in length. The element sequence consists of several small and unusually GC-rich direct repeats with recurring intervening sequences. In addition, STAR-like elements may be present in related staphylococcal species.
Lip–jaw and tongue–jaw coordination during rate-controlled syllable repetitions
2000-04-01

The present study investigated the relationship between functionally relevant compound gestures and single-articulator component movements of the jaw and the constrictors lower lip and tongue tip during rate-controlled syllable repetitions. In nine healthy speakers, the effects of speaking rate (3 vs 5 Hz), place of articulation, and vowel type during stop consonant–vowel repetitions (/pa/, /pi/, /ta/, /ti/) on the amplitude and peak velocity of differential jaw and constrictor opening–closing movements were measured by means of electromagnetic articulography. Rather than homogeneously scaled compound gestures, the results suggest distinct control mechanisms for the jaw and the constrictors. In particular, jaw amplitude was closely linked to vowel height during bilabial articulation, whereas the lower lip component amplitude turned out to be predominantly rate sensitive. However, the observed variability across subjects and conditions does not support the assumption that single-articulator gestures directly correspond to basic phonological units. The nonhomogeneous effects of speech rate on articulatory subsystem parameters indicate that single structures are differentially rate sensitive. On average, an increase in speech rate resulted in a more or less proportional increase of the steepness of peak velocity/amplitude scaling for jaw movements, whereas the constrictors were less rate sensitive in this respect. Negative covariation across repetitions between jaw and constrictor amplitudes has been considered an indicator of motor equivalence. Although significant in some cases, such a relationship was not consistently observed across subjects. Considering systematic sources of variability such as vowel height, speech rate, and subjects, jaw–constrictor amplitude correlations showed a nonhomogeneous pattern strongly depending on place of articulation.
Simple and Sensitive Binding Assay for Measurement of Adenosine Using Reduced S-Adenosylhomocysteine Hydrolase
2000-04-01

Abstract Background: Adenosine has been suggested to play an important role in the regulation of renal function. We developed a simple and sensitive binding assay for the detection of adenosine based on the displacement of [3H]adenosine from S-adenosylhomocysteine (SAH) hydrolase in its reduced form. Methods: SAH hydrolase was purified to apparent homogeneity from bovine kidney by standard chromatographic methods. SAH hydrolase was converted in its reduced form, which had the advantage that the SAH hydrolase is enzymatically inactive. This reduced enzyme retains its ability to bind adenosine with high affinity. To determine adenosine in urine or tissues, samples must be deproteinized (e.g., with 10 g/L sulfosalicylic acid or 0.6 mol/L perchloric acid). Results: The reduced SAH hydrolase bound adenosine with a dissociation constant of 33.0 ± 2 nmol/L. Displacement of adenosine binding by the adenine 5′-nucleotides, adenine and hypoxanthine, required &amp;gt;1000-fold higher concentrations than adenosine itself. The intra- and interassay imprecision (CV) was &amp;lt;3.9% and 7.8%, respectively, and the values obtained showed acceptable correlation with those by HPLC. Conclusions: The highly sensitive adenosine-binding protein assay is a simple test that allows detection of adenosine in samples with small volumes without purification, and is in this respect superior to HPLC.
Effects of Cerivastatin on Human Arterial Smooth Muscle Cell Proliferation and Migration in Transfilter Cocultures
2000-04-01

Statins competitively inhibit 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase activity reducing mevalonate synthesis. In this study, antiproliferative and antimigratory effects of the new compound cerivastatin were analyzed and compared with classic statins of the first and second generation using mono- and cocultures of human arterial smooth muscle (haSMC) and endothelial (haEC) cells. Effects on the mitotic index and mitochondrial activity of haEC and haSMC monocultures were tested using BrdU enzyme-linked immunosorbent assay (ELISA) and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) tests, respectively. In lactate dehydrogenase (LDH) assays, cytotoxicity of statins was studied. Transfilter cocultures were performed for 14 days to evaluate haSMC growth under the stimulatory effect of proliferating haEC, which release growth factors [e.g., platelet-derived growth factor (PDGF)]. The hydrophobic statins simvastatin, lovastatin, and atorvastatin significantly inhibited haSMC and haEC growth in monocultures at 0.5-50 microM. However, most potent effects were exerted by cerivastatin in 10- to 30-fold lower doses without any significant cytotoxicity. More important, cerivastatin showed also significant effects on haSMC proliferation and migration in transfilter cocultures at extremely low doses (IC50, 0.04-0.06 microM), even when applied exclusively to the endothelial side and in the presence of low-density lipoprotein (LDL). Addition of mevalonate abolished the effects of cerivastatin completely. Even in the presence of growth-stimulating haEC and LDL, cerivastatin was found to be the most potent inhibitor of haSMC proliferation and migration in doses that also can be reached in human serum after oral drug administration. The results support the concept that statins seems to influence additional cellular mechanisms beyond cholesterol reduction, which might also have a relevance for the prevention of restenosis.
Argon Plasma Coagulation in Bronchology: A New Method—Alternative or Complementary?
2000-04-01

Argon plasma coagulation (APC) is a thermal coagulation technique that uses ionized argon to transmit high-frequency electrical current, contact free, to tissue. APC has been used in surgery for more than 20 years, particularly for the hemostasis of superficial bleeding. Although APC has become well established in gastrointestinal endoscopy since its introduction in 1991, very few reports of its use in bronchoscopy exist to date. From June 1994 to June 1998. 364 patients (80 women. 284 men), 88% with a confirmed malignant tumor, were treated prospectively in a total of 482 sessions. The single most common indication was recanalization of malignant airway stenoses (186 patients). The defined therapy objective was achieved with good results in 67% of patients. More than 90% of interventions were performed with rigid bronchoscopy. Despite less penetration compared with Nd:YAG laser, extensive bronchial tumors were treatable, in which coagulated tumor fractions were removed either with forceps or bronchoscope tip. The second indication was bleeding in the central airways (119 patients). Acute hemostasis was achieved in 118 patients, 20% in whom the flexible technique under local anesthesia was used. In 34 patients. APC was successfully used to recanalize occluded stents. Rare indications included benign endobronchial tumor, fistula conditioning before fibrin adhesion, and the treatment of scar tissue stenosis. Summarizing all complications, a rate of 3.7% “per treatment” was recorded. Two patients died within 24 hours; their deaths were not directly related to APC. APC is an effective and safe technique for the treatment of bronchologic tumor ablation and hemostasis and can be used with local anesthetic with flexible bronchoscopy or rigid bronchoscopy with general anesthesia. Compared with Nd:YAG laser. APC is an economic alternative technique offering more effective hemostasis. Furthermore. APC is of particular value as a compliment to well-known techniques, increasing the options in interventional bronchoscopy. Journal of Bronchology7:109-117, 2000. APC, argon plasma coagulation; HF currency, high-frequency electrical current
Characterization of an HPr Kinase Mutant of Staphylococcus xylosus
2000-04-01

ABSTRACT The Staphylococcus xylosus gene hprK , encoding HPr kinase (HPrK), has been isolated from a genomic library. The HPrK enzyme, purified as a His 6 fusion protein, phosphorylated HPr, the phosphocarrier protein of the bacterial phosphotransferase system, at a serine residue in an ATP-dependent manner, and it also catalyzed the reverse reaction. Therefore, the enzyme constitutes a bifunctional HPr kinase/phosphatase. Insertional inactivation of the gene in the genome of S. xylosus resulted in the concomitant loss of both HPr kinase and His serine-phosphorylated-HPr phosphatase activities in cell extracts, strongly indicating that the HPrK enzyme is also responsible for both reactions in vivo. HPrK deficiency had a profound pleiotropic effect on the physiology of S. xylosus . The hprK mutant strain showed a severe growth defect in complex medium upon addition of glucose. Glucose uptake in glucose-grown cells was strongly enhanced compared with the wild type. Carbon catabolite repression of three tested enzyme activities by glucose, sucrose, and fructose was abolished. These results clearly demonstrate the prominent role of HPr kinase in global control to adjust catabolic capacities of S. xylosus according to the availability of preferred carbon sources.
Evolution Semigroups and Product Formulas for Nonautonomous Cauchy Problems
2000-04-01

In this paper, we study nonautonomous Cauchy problems (NCP) {u̇(t) = A(t)u(t)u(s) = x ∈ X for a family of linear operators (A(t))t∈I on some Banach space X by means of evolution semigroups. In particular, we characterize "stability" in the so called "hyperbolic case" on the level of evolution semigroups and derive a product formula for the solutions of (NCP). Moreover, in Section 4 we connect the "hyperbolic" and the "parabolic" case by showing, that integrals ∫ts A(τ) dτ always define generators. This yields another product formula.
Synthesis of a Biotinated Lipofullerene as a New Type of Transmembrane Anchor
2000-04-01

As a prototype for a new class of lipid membrane components, the lipophilic fullerene derivative (so-called lipofullerene) 1 was synthesized and characterized. This mixed [1:5]-hexakisadduct consists of ten long alkyl chains within five didodecyl malonate addends and a linker malonate carrying a (+)-biotin unit as part of an amphiphilic spacer. The malonates are attached to the fullerene core in an octahedral addition pattern, which was achieved by two successive cyclopropanation sequences with the functional precursor malonate 8 and dodecyl malonate 10. The final step of the synthesis of 1 was the attachment of activated biotin 5 with the deprotected precursor 11. Binding experiments followed by reflectometric interference spectroscopy [RIfS] proved the capability of 1 to bind specifically the protein streptavidin (SA) through the biotin unit. The amphiphilic behavior of 1 was demonstrated by Langmuir Blodgett (LB) film investigations.
Methaemoglobinaemia after peribulbar blockade: an unusual complication in ophthalmic surgery
2000-04-01

Editor,—Peribulbar blockade is frequently used for anaesthesia in ophthalmic surgery. Owing to its short onset time and low incidence of cardiac and central nervous system toxicity, the local anaesthetic prilocaine is a popular choice for peribulbar blockade. Prilocaine is, however, the most potent methaemoglobin forming local anaesthetic. We report a case of prilocaine induced methaemoglobinaemia after peribulbar blockade for ophthalmic surgery. ### CASE REPORT A 27 year old Romanian woman presented with a detached retina requiring surgical repair. Her medical history was significant for insulin dependent diabetes mellitus complicated by chronic renal failure, anaemia, and diabetic retinopathy. Her daily medication included captopril 25 mg, verapamil 240 mg, isosorbide dinitrate 40 mg, and frusemide 40 mg. A mixture of prilocaine 80 mg, bupivacaine 30 mg, hyaluronidase, and naphazoline was used to perform a peribulbar anaesthesia. Vital signs at the beginning ...
Spectral and asymptotic properties of resolvent-dominated operators
2000-04-01

Abstract Let A and B be (not necessarily bounded) linear operators on a Banach lattice E such that |( s – B) -1 x|≤ (s – A) -1 |x| for all x in E and sufficiently large s ∈ R. The main purpose of this paper is to investigate the relation between the spectra σ( B ) and σ( A ) of B and A , respectively. We apply our results to study asymptotic properties of dominated C 0 -semigroups.
Diagnostic Protein Expression in Human Muscle Biopsies
2000-04-01

Using immunohistochemistry in diagnosing neuromuscular diseases is meant to enhance the diagnostic yield in two ways. The first application aims at visualizing molecules which are developmentally, neurally, and/or immunologically regulated and not expressed by normal muscle. They are upregulated in pathological conditions and may help assign a given muscular biopsy to one of the main diagnostic entities (muscular dystrophies, inflammatory myopathy, neurogenic atrophy). In the past, muscle‐specific molecules with a defined expression pattern during fetal myogenesis served as antigens, with the rationale that the developmental program was switched on in new fibers. Recently, myofibers in diseased muscle are thought of as targets of stimuli which are released by macrophages in muscular dystrophy, by lymphocytes in inflammatory myopathies, or by a lesioned peripheral nerve in neurogenic atrophies. This has somewhat blurred the borders between the diagnostic groups, for certain molecules, e.g. cytokines, may be upregulated after experimental necrotization, denervation, and also in inflammatory myopathies. In the second part of this review we summarise the experiences of a Centre in the North of England that specialises in the diagnosis and clinical support of patients with muscular dystrophy. Emphasis is placed on the use of protein expression to guide mutation analysis, particularly in the limb‐girdle muscular dystrophies (a group of diseases that are very difficult to differentiate on clinical grounds alone). We confirm that genetic analysis is essential to corroborate the results of protein analysis in certain conditions (particularly in calpainopathy). However, we conclude that analysing biopsies for abnormal protein expression is very useful in aiding the decision between alternative diagnoses.
Bag‐1 and Bcl‐2 Gene Transfer in Malignant Glioma: Modulation of Cell Cycle Regulation and Apoptosis
2000-04-01

Bag‐1 is a heat shock 70 kDa (Hsp70)‐binding protein that can collaborate with Bcl‐2 in suppressing apoptosis under some conditions. Here, we report that 11 of 12 human glioma cell lines express Bag‐1 protein in vitro. Moreover, 15 of 19 human glioblastomas expressed Bag‐1 as assessed by immunohistochemistry in primary tumor specimens. To examine the biological effects of Bag‐1 in glioma cells, we expressed Bag‐1 or Bcl‐2 transgenes in 2 human malignant glioma cell lines, LN‐18 and LN‐229. Bag‐1 significantly slowed glioma cell growth and reduced clonogenicity of both cell lines in vitro. Coexpressed Bcl‐2 abrogated these effects of Bag‐1. Intracranial LN‐229 glioma xenografts implanted into nude mice revealed a substantial growth advantage afforded by Bcl‐2. Bag‐1 had no such effect, either in the absence or presence of Bcl‐2. Upon serum starvation in vitro , Bcl‐2 prevented cell death whereas Bag‐1 did not. Both Bcl‐2 and Bag‐1 slowed proliferation of serum‐starved cells when expressed alone. Importantly, coexpression of Bcl‐2 and Bag‐1 provided a distinct growth advantage under conditions of serum starvation that is probably the result of (i) the death‐preventing activity of Bcl‐2 and (ii) the property of Bag‐1 to overcome a Bcl‐2‐mediated enhancement of exit from the cell cycle. In contrast to these Bcl‐2/Bag‐1 interactions observed under serum starvation conditions, Bag‐1 did not further enhance the strong protection from staurosporine‐, CD95 (Fas/Apo1) ligand‐, Apo2 ligand (TRAIL)‐ or chemotherapeutic drug‐induced apoptosis afforded by Bcl‐2. Taken together, these results indicate a role for Bag‐1/Bcl‐2 interactions in providing a survival advantage to cancer cells in a deprived microenvironment that may be characteristic of ischemic/hypoxic tumors such as human glioblastoma multiforme, and suggest that Bcl‐2/Bag‐1 interactions also modulate cell proliferation.
Postglomerular vasoconstriction induced by dopamine D3receptor activation in anesthetized rats
2000-04-01

In the present study we investigated the renal hemodynamic effects of dopamine D 3 receptor activation by R(+)-7-hydroxy-dipropylaminotetraline (7-OH-DPAT) in thiopental-anesthetized Sprague-Dawley rats. In clearance experiments infusion of 7-OH-DPAT (0.01–1.0 μg ⋅ kg − 1 ⋅ min − 1 ) dose-dependently elevated glomerular filtration rate (GFR) without affecting mean arterial blood pressure (MAP). In renal blood flow experiments 7-OH-DPAT infusion (1.0 μg ⋅ kg − 1 ⋅ min − 1 ) increased GFR by 16 ± 2%, associated with an unexpected fall in renal blood flow by 20 ± 3% and a significant elevation of renal vascular resistance by 18 ± 3%. The renal hemodynamic changes were not influenced by pretreatment with the D 2 -receptor antagonist S(−)-sulpiride but were completely abolished during D 3 receptor inhibition by 5,6-dimethoxy-2-(di-n-propylamino)indane (U-99194A). In micropuncture experiments 7-OH-DPAT (1.0 μg ⋅ kg − 1 ⋅ min − 1 ) significantly elevated stop-flow pressure measured in the early proximal tubules and reduced hydrostatic pressure at the first branching point of the efferent arteriole without altering MAP. We conclude from these data that pharmacological activation of dopamine D 3 receptors affects renal hemodynamics in anesthetized rats by preferential postglomerular vasoconstriction.
Subcellular localization and light-dark control of ornithine decarboxylase in the unicellular green alga Chlamydomonas reinhardtii
2000-04-01

The polyamines putrescine, spermidine and spermine are required for cell proliferation of both eukaryotic and prokaryotic organisms. In plant cells, putrescine, which is also the precursor of spermidine, is derived from ornithine by the action of ornithine decarboxylase (ODC, EC 4.1.1.17) or from arginine by arginine decarboxylase (ADC, EC 4.4.4.19). In the unicellular green alga Chlamydomonas reinhardtii, ODC activity exceeds ADC activity by orders of magnitude as shown in the present communication, indicating that biosynthesis of polyamines is controlled by ODC activity in this organism. ODC was localized in the cytosol and was found to consist of 50 kDa subunits as revealed by affinity labeling with [ 3 H]difluoromethylornithine and subsequent SDS-PAGE and fluorography. Its activity was much higher in light- than in dark-adapted (starved) cells. After transfer from darkness to light, a rapid increase in ODC activity was observed. This light-induced increase in ODC activity could be completely abolished by addition of cycloheximide, an inhibitor of protein biosynthesis, but not by actinomycin D inhibition of transcription. Up-regulation of ODC activity after onset of illumination could be prevented by addition of the photosystem II inhibitor 3-(3'-4'-dichlorophenyl)-1,1-dimethyl-urea. ODC activity was found to be correlated with the ATP level both in light- and dark-adapted cells. ODC half-lives of 42 and 83 min were determined for dark- and light-adapted cells, respectively.
Acute lymphoblastic leukaemia: correlation between morphological/immunohistochemical and molecular biological findings in bone marrow biopsy specimens
2000-04-01

Acute leukaemia can be subtyped in bone marrow sections with a limited panel of antibodies suitable for use on paraffin wax embedded sections (against CD3, CD10, CD20, CD79a, myeloperoxidase, and lysozyme). In patients with ALL and a diagnostically equivocal immunophenotype, gene rearrangement analysis might indicate whether the B or T cell lineage is involved.