julilili42/papers huggingface dataset:
The genus Pseudis (Anura: Pseudidae) in Rio Grande do Sul, southern Brazil, with description of a new species
2000-01-01

Abstract A new species of Pseudis is described from São Francisco de Paula, Rio Grande do Sul, Brazil. It is known from the southern parts of the Serra Geral where it occurs in grassland, inhabiting permanent ponds and still-water zones of slow flowing creeks. It is characterized by a paired vocal sac and a bulbous thumb, considerably widened at the base. It is distinguished from P. minutus by its different call, body coloration, rounded snout, and a more robust body with shorter hindlimbs. Advertisement call, tadpole, and life history are described. The taxonomy of the family Pseudidae in Rio Grande do Sul is discussed, supporting the synonymy of Lysapsus mantidactylus and P. meridionalis with P. minutus.
In Vitro Evaluation of Teratogenic Effects by Time-Varying MR Gradient Fields on Fetal Human Fibroblasts
2000-01-01

The purpose of this study was to evaluate the influence on fetal cell growth in vitro of rapidly changing magnetic gradient fields such as those produced by the gradient coils of a typical magnetic resonance (MR) imager. The static magnetic field and the radiofrequency pulses were disabled during all measurements. Human fetal fibroblasts were placed within a specially designed MR-compatible incubation system inside the magnet. Trapezoid-shaped waveforms of 500 and 75 Hz base frequency and an amplitude of 2 mT were applied for 2-24 hours. Proliferation of the cells was monitored for 3 weeks after exposure. Cell cycle analysis was performed until 24 hours after exposure to detect alterations in cell division. Tests were performed under two different conditions of growth to detect increased as well as decreased proliferation effects. None of these tests showed differences in proliferation and cell cycle distribution between exposed and nonexposed cells.
The novel heterodinucleoside dimer 5-FdU-NOAC is a potent cytotoxic drug and a p53-independent inducer of apoptosis in the androgen-independent human prostate cancer cell lines PC-3 and DU-145
2000-01-01

5-FdU-NOAC inhibits thymidylate synthase and cell cycle progression causing proliferation arrest and apoptosis in DU-145 and PC-3 cells, suggesting a potential role of 5-FdU-NOAC for the treatment of prostate cancer.
Separation and absolute configuration of the enantiomers of a degradation product of the new inhalation anesthetic sevoflurane (Dedicated to Professor Nakanishi on the occasion of his 75th birthday)
2000-01-01

In a rebreathing anesthesia circuit, the inhaled anesthetic sevoflurane degrades into at least two products, termed "compound A" and "compound B." The enantiomer separation of the chiral compound B (1,1,1,3,3-pentafluoro-2-(fluoromethoxy)-3-methoxypropane ) by capillary gas chromatography (cGC) using heptakis (2,3-di-O-acetyl-6-O-tert-butyldimethylsilyl)-beta-cyclodextrin as chiral selector was studied. With this cyclodextrin derivative diluted in the polysiloxane PS 86, an unprecedented high separation factor alpha of 4.1 (at 30 degrees C) was found. Consequently, the enantiomers of compound B were isolated by preparative GC and their specific rotations were measured. In addition, their absolute configurations were determined by X-ray crystallography. To collect the X-ray data, single crystals of both enantiomers were grown in situ on the diffractometer. The levorotatory enantiomer B(-) has the R-configuration while the dextrorotatory enantiomer B(+) has the S-configuration. The elution order of the compound B enantiomers on heptakis (2,3-di-O-acetyl-6-O-tert-butyldimethylsilyl)-beta-cyclodextrin is R before S.
Nerve Conduction Studies in Multiple System Atrophy
2000-01-01

To study the frequency and severity of peripheral neuropathy in multiple system atrophy (MSA), we performed nerve conduction studies in 42 MSA patients suffering from either cerebellar MSA (MSA-C) or parkinsonian MSA (MSA-P). Abnormal nerve conduction was present in 24% of the patients. Abnormalities were significantly more frequent in MSA-P (43%) compared to MSA-C (14%). Motor nerve conduction velocities were reduced in 4% of the MSA-C and in 7% of the MSA-P patients. Abnormal compound muscle action potentials were more frequent in MSA-P (29% versus 7% in MSA-C) pointing to a more pronounced loss of motor axons in this subgroup. Sensory nerve conduction velocities were abnormal in 4% of the MSA-C and 14% of the MSA-P patients, and mean sensory nerve action potentials were normal in all MSA-C and reduced in 7% of the MSA-P patients. The data provide evidence that the peripheral nervous system is differentially affected in MSA-C and MSA-P.
Stringy Hodge numbers and Virasoro algebra
2000-01-01

In this paper we define for singular varieties X a rational number c 1,n-1 st (X) which is a stringy version of the product of Chern numbers c 1 and c n-1 We show that the number c 1,n-1 st (X) can be expressed via stringy Hodge numbers of singular X in the same way as c 1 c n-1 expresses via usual Hodge numbers for smooth manifolds.Our result provides some evidences for the existence of quantum cohomology theory of singular varieties X based on representation of the Virasoro algebra whose central charge is the rational number e st (X) which equals the stringy Euler number of X.
Endothelial Dysfunction in Diabetes Mellitus
2000-01-01

Diabetes mellitus and impaired glucose tolerance are linked to increased cardiovascular morbidity and mortality. Vascular disease is directly associated with plasma glucose levels, and reduction of these levels forestalls to a certain extent the vascular complications of diabetes, such as myocardial infarction, nephropathies, and retinopathies. In addition to hyperglycemia, there are other risk factors that play a prominent role, such as hypertension, hyperlipidemia, and genetic factors. Endothelial dysfunction is one of the major factors in the development of cardiovascular disease. The vascular endothelium regulates the blood flow by tightly controlling the coagulation system, cell-cell interaction, and vascular tone. These functions are disturbed in diabetic patients. In diabetics, endothelin-1 levels are increased, leading to vasoconstriction. Endothelin levels are directly related to plasma glucose levels. In addition, the endothelial cell-NO axis is disturbed. NO release and function are impaired. This seems to be dependent upon hyperglycemia and genetic factors. Impaired NO function also results in vasoconstriction. Furthermore, enhanced vascular permeability is seen in diabetics. This appears to be related to impaired endothelial cell relaxation and reactive oxygen species as well as advanced glycosylated end products (AGEs). The complex changes seen in diabetes and even prediabetes are therefore related to numerous derailments related to endothelial dysfunction, and no single therapeutic approach is likely to solve the problem of vascular complications.
β-Blockers of the Third Generation Inhibit Endothelin-1 Liberation, mRNA Production and Proliferation of Human Coronary Smooth Muscle and Endothelial Cells
2000-01-01

Endothelin-1 (ET-1) plays an important role in atherogenesis. The aim of the study reported here was to investigate the effects of the third generation beta-blockers nebivolol and carvedilol on ET-1 liberation, preproendothelin-1 production and on proliferation of human coronary cells. Human coronary endothelial (HEC) and smooth muscle cells (HCSMC) were grown with carvedilol or nebivolol (10(-7)-10(-5) mol/l). Incubation for 1, 2 or 7 days resulted in an 80% concentration- and time-dependent reduction in HCSMC proliferation. beta-blockers such as propranolol or metoprolol did not influence cell proliferation. Nebivolol (10(-7) mol/l) inhibited accelerated HCSMC proliferation in the presence of growth factors such as transforming growth factor-beta1 or platelet-derived growth factor BB. During incubation with nebivolol or carvedilol ET-1 secretion decreased. For nebivolol this is a result of a reduction in preproendothelin-1 mRNA levels. beta-blockers of the third generation that reduce the cell proliferation and ET-1 secretion may represent strategies with great promise for antiproliferative therapy of coronary heart disease.
Low‐dose melphalan induces favourable responses in elderly patients with high‐risk myelodysplastic syndromes or secondary acute myeloid leukaemia
2000-01-01

We treated 21 elderly patients with high‐risk myelodysplasia ( n = 14) or secondary acute myeloid leukaemia ( n = 7) with 2 mg of melphalan orally once a day until a complete peripheral response was obtained or until there was evidence of treatment failure. We observed seven (30%) complete and two (10%) partial peripheral responses occurring within 4–16 weeks and lasting for 12 + to 55 weeks. In relapse, retreatment was successful in most of the patients. Responses were associated with the absence of complex cytogenetic abnormalities and with a normal or reduced bone marrow cellularity.
The use of reduced doses of amifostine to ameliorate nephrotoxicity of cisplatin/ifosfamide-based chemotherapy in patients with solid tumors
2000-01-01

This study evaluates the degree of kidney damage during cisplatin/ifosfamide-based combination chemotherapy and its possible prevention by amifostine. Thirty-one patients with solid tumors stratified according to pretreatment were randomized to receive cisplatin/ifosfamide-based chemotherapy with or without amifostine (1000 mg absolute) given as a short infusion prior to cisplatin. Chemotherapy consisted of cisplatin (50 mg/m2), ifosfamide (4 g/m2) and either etoposide (500 mg/m2) (VIP regimen) or paclitaxel (175 mg/m2) (TIP regimen) repeated at 3 weekly intervals. For all patients the glomerular filtration rate (GFR) measured by creatinine clearance, serum creatinine, electrolytes and differential urinary protein excretion were determined prior to, during and after each treatment cycle. A total of 62 cycles of chemotherapy were evaluable. In the amifostine arm the GFR was almost completely maintained after application of two cycles of chemotherapy (121 to 108 ml/min), whereas in the control group a 30% reduction of the GFR (105 to 80 ml/min) was observed. In both groups marked increases of glomerular and tubular marker profiles peaking at day 3 after chemotherapy were found with a nearly complete reversibility of these changes prior to the next chemotherapy cycle. Patients receiving amifostine had a lower degree of hypomagnesemia, as well as a lower urinary excretion of N-acetyl-glucosaminidase and albumin, indicating less tubular damage compared to the control patients. Treatment with 1000 mg amifostine resulted in an almost complete preservation of GFR. This corresponded to a slightly reduced excretion of tubular marker proteins and a lower incidence of hypomagnesemia during chemotherapy in amifostine patients compared to controls. This dose of amifostine may be sufficient for nephroprotection in patients without pre-existing risk factors for renal damage who undergo a restricted number of chemotherapy cycles.
Escape mechanisms in tumor immunity: a year 2000 update.
2000-01-01

The current consensus of opinion has it that most or possibly all tumors, spontaneous as well as induced, are immunogenic, expressing antigens in a form recognizable by the host immune system. Accordingly, in order to progress, tumors have to evolve strategies for evading immune responses. The purpose of this review is to consider the current status of knowledge concerning these different tumor escape strategies. It represents an update of an article originally published in this journal in 1997 (Pawelec, Zeuthen, and Kiessling, 1997). Therefore, it focuses mostly on publications that have appeared since then, illustrating the impressive accumulation of new data since that time and the importance currently attributed to studies of tumor escape from the immune response.
Personal UV Dosimetry by <i>Bacillus subtilis</i> Spore Films
2000-01-01

&lt;b&gt;Background:&lt;/b&gt; Ultraviolet radiation (UVR) is known to be the most important risk factor for melanoma and non-melanoma skin cancers. Until today it has been impossible to measure reliably UVR in the frame of epidemiological studies. The recent development of a spore film containing spores of Bacillus subtilis resulted in a new method of UV measurement by personal dosimetry. &lt;b&gt;Methods:&lt;/b&gt; The practical application of dosimeters was tested in 18 study persons under different circumstances of UV exposure and in 4 different geographical regions. &lt;b&gt;Results:&lt;/b&gt; Eleven children carried dosimeters on their shoulders for 1 day, playing in- and outdoors on a sunny day in summertime. Their whole-day values ranged from 0.1 to 1.5 minimal erythema doses (MED) per day with a mean of 0.71 MED (±0.44). Four lifeguards in a public swimming-pool carried dosimeters on their shoulders for 11 days and received UV exposures ranging from 3.6 to 9.5 MED (mean 5.9 ± 1.88). Three mountain guides with dosimeters attached to the lateral head in different mountain regions at 23 mountaineering activities received daily exposures of 4.44–17.07 MED (mean 11.9 ± 3.8). &lt;b&gt;Conclusion:&lt;/b&gt; B. subtilis spore film dosimeters can be applied to different study persons including children and mountain guides under different climatic conditions. A broad range of UV exposures can reliably be measured with this method.
Fibroblast Differentiation in Subcutaneous Fibrosis after Postmastectomy Radiotherapy
2000-01-01

In order to acquire a better understanding of the mechanism of radiation-induced fibrosis, we studied the differentiation of normal skin fibroblasts cultured from breast cancer radiotherapy patients with different risk of fibrosis. The differentiation state of fibroblasts was characterized in clonal cultures using established cytomorphological criteria. Collagen synthesis was determined by 3H-proline incorporation into pepsin-resistant protein. Radiation-induced inactivation of fibroblasts was paralleled by an increase in terminally differentiated fibrocytes, demonstrating that premature terminal differentiation is an important response to irradiation of fibroblasts from radiotherapy patients. Surviving colony-forming fibroblasts showed a change in differentiation with an increase in the ratio L:E of progenitor fibroblasts in late (L) compared to early (E) differentiation states. Furthermore, increased collagen production was observed after irradiation. The results provide evidence supporting a role of terminal fibroblast differentiation in radiation-induced fibrosis and imply that the progenitor population surviving radiotherapy might be more prone to terminal differentiation than before radiotherapy.
Brightness and color of rapidly moving objects: The visual appearance of a large sphere revisited
2000-01-01

An object at relativistic speed is seen as both rotated and distorted when it is large or close by so that it subtends a large solid angle. This is a consequence of the aberration effect and is obtained by purely geometric considerations. In this paper it is pointed out and illustrated that a photorealistic image of such an object would actually be dominated by the Doppler and searchlight effects, which would be so prominent as to render the geometric apparent shape effectively invisible.
Experience with Growth Hormone Therapy in Turner Syndrome in a Single Centre: Low Total Height Gain, No Further Gains after Puberty Onset and Unchanged Body Proportions
2000-01-01

The experience gained since 1987, through observation of 85 girls with Turner syndrome under growth hormone (GH) treatment, has enabled the analysis of one of the largest cohorts. Our results show that age, karyotype and height reflect the heterogeneity of the patients examined at our growth centre. In 47 girls, followed over 4 years on GH (median dose 0.72 IU/kg/week), the median age was 9.4 years and mean height SDS was –3.55 (Prader) and –0.14 (Turner-specific), while height and other anthropometrical parameters [weight, body mass index, sitting height (SH), leg length (LL) SH/LL, head circumference, arm span] were documented and compared to normative data as well as to Turner-specific references established on the basis of a larger (n = 165) untreated cohort from Tübingen. The latter data are also documented in this article. Although there was a trend towards normalization of these parameters during the observation period, no inherent alterations in the Turner-specific anthropometric pattern occurred. In 42 girls who started GH treatment at a median age of 11.8 years, final height (bone age &gt;15 years) was achieved at 16.7 years. The overall gain in height SDS (Turner) from start to end of GH therapy was 0.7 (± 0.8) SD, but 0.9 (± 0.6) SD from GH start to onset of puberty (spontaneous 12.2 years, induced 13.9 years) and –0.2 (± 0.8) from onset of puberty to end of growth. Height gain did not occur in 12 patients (29%) and a gain of &gt; 5 cm was only observed in 16 patients (38%). Height gain correlated positively with age at puberty onset, duration, and dose of GH, and negatively with height and bone age at the time GH treatment started. Final height correlated positively with height SDS at GH start and negatively with the ratio of SH/LL (SDS). We conclude that, in the future, GH should be given at higher doses, but oestrogen substitution should be done cautiously, owing to its potentially harmful effect on growth. LL appears to determine height variation in Turner syndrome and the potential to treat short stature successfully with GH.
FTICR-mass spectrometry for high-resolution analysis in combinatorial chemistry
2000-01-01

The diversity of compound collections required for finding lead structures in pharmaceutical research can be provided by means of combinatorial organic chemistry. The resultant enormous number of single compounds but also of compound mixtures represents a challenge for the analyst. With the introduction of Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS or FT-MS), a new and, as yet, not widespread mass spectrometric technique (a means of analysis of such compound libraries with a very high mass resolution) high mass accuracy and high sensitivity has become available. Moreover, in combination with electrospray ionization (ESI), not only high-throughput measurements via flow-injection analysis (FIA) but also coupling with separation techniques such as high-performance liquid chromatography (HPLC) or capillary electrophoresis (CE) is possible. Structural verification by way of decomposing ions (MS(n); n > or = 2) using a variety of different dissociation techniques can be performed by FTICR-MS. This is the first review specifically covering applications of FTICR-MS in the field of combinatorial chemistry.
Pathogenesis and Symptomatology of Cholelithiasis in Childhood
2000-01-01

&lt;i&gt;Questions:&lt;/i&gt; How may gallstones develop if there is no hemolytic disorder and no malformation or alteration of the gallbladder and cystic ducts? Was there a change in the incidence of stones and the assignment of the patients to different age groups? The literature gives answers to these questions on the basis of only few cases. Therefore, a relatively large prospective database of collected cases during 30 years shall be used to give additional answers. &lt;i&gt;Methods:&lt;/i&gt; The data are derived from 111 children with symptomatic gallstones without hemolytic diseases. 109 of them required operative therapy. They were examined preoperatively and postoperatively maximum during 30 years of follow-up as well according to a defined program. This program includes taking the patient’s history, evaluation of clinical, radiological including sonographical examination, exclusion of hemolytic primary diseases, histological investigation of intraoperatively gained specimens of the gallbladder, and the spectroscopic qualitative as well as semiquantitative analysis of stones and bile. &lt;i&gt;Results:&lt;/i&gt; (1) The qualitative and quantitative composition of the stones is different in the four age groups. (2) The causes of lithogenesis are different in the four age groups. (3) Children with long-term TPN, after cardiopulmonary bypass operations, after extended small bowel resection, suffering from obesity, and girls using hormonal contraception are at risk of developing gallstones. We recommend to observe these patients by repeated ultrasound controls for gallstone formation during a minimum of 10 years. (4) Malformations and pathological alterations of the gallbladder are rare causes for increased lithogenity. The gallbladder appeared morphologically normal in 61% of patients with symptomatic gallstones. (5) An increased frequency of gallstones during the last 30 years was only observed in the age group under 1 year.
Tumor-Biological Factors Upa and PAI-1 as Stratification Criteria of a Multicenter Adjuvant Chemotherapy Trial in Node-Negative Breast Cancer
2000-01-01

In axillary node-negative primary breast cancer, 70% of the patients will be cured by locoregional treatment alone. Therefore, adjuvant systemic therapy is only needed for those 30% of node-negative patients who will relapse after primary therapy and eventually die of metastases. Traditional histomorphological and clinical factors do not provide sufficient information to allow accurate risk group assessment in order to identify node-negative patients who might benefit from adjuvant systemic therapy. In the last decade various groups have reported a strong and statistically independent prognostic impact of the serine protease uPA (urokinase-type plasminogen activator) and its inhibitor PAI-1 (plasminogen activator inhibitor type 1) in node-negative breast cancer patients. Based on these data, a prospective multicenter therapy trial in node-negative breast cancer patients was started in Germany in June 1993, supported by the German Research Association (DFG). Axillary node-negative breast cancer patients with high levels of either or both proteolytic factors in the tumor tissue were randomized to adjuvant CMF chemotherapy versus observation only. Recruitment was continued until the end of 1998, by which time 684 patients had been enrolled. Since then, patients have been followed up in order to assess the value of uPA and PAI-1 determination as an adequate selection criterion for adjuvant chemotherapy in node-negative breast cancer patients. This paper reports on the rationale and design of this prospective multicenter clinical trial, which may have an impact on future policies in prognosis-oriented treatment strategies.
Speaker discrimination in a foreign language: first language environment, second language learners
2000-01-01

A witness to a crime may be required to identify a speaker based on voice samples from a language which is not their first language. Previous experimental work has shown that knowledge of a language has an effect on an individual's ability to identify speakers. This paper examines whether this ability increases over the course of the British four-year language degree. The results from a series of different open-test voice line-up presentations showed that listener ability improved on beginning to study a foreign language, yet showed no unambiguous improvement after the second semester of study.
Microsatellite Instability in Thyroid Papillary Carcinoma and Multinodular Hyperplasia
2000-01-01

Microsatellite instability (MSI) is a molecular landmark of mutations in DNA mismatch repair genes. The impaired efficiency of DNA repair mechanisms promotes carcinogenesis as well as contributes to tumour progression. Until now, only few studies on MSI in thyroid tumours have been published. Therefore, the aim of the present study was to investigate MSI as a possible characteristic feature of thyroid tumours. The analysis of 12 thyroid papillary carcinomas and 17 multinodular hyperplasias at 13 microsatellite loci showed MSI and loss of heterozygosity (LOH) in both types of lesion, with more alterations noted in the papillary thyroid carcinomas (in 65%) than in multinodular hyperplasia (in 35%). In carcinomas, LOH occurred more frequently than MSI, while in multinodular hyperplasia the LOH/MSI ratio is almost equal.