julilili42/papers huggingface dataset:
A morphological analysis of marsupial mammal higher-level phylogenetic relationships
2003-06-01

Abstract Phylogenetic relationships among marsupial taxa have proven to be more complex than the simple grouping of species by continent. Recent marsupials are distributed across the New World, Australia, New Guinea, and certain neighboring islands. Morphological characteristics of various groups bridge different geographical areas. We investigated the origin of these characteristics by assembling a morphological data matrix consisting of a new suite of 149 postcranial characters and incorporated a series of previously published data on the craniodental (76 characters) and soft tissue (5 characters) anatomy. Twenty-one marsupial terminal taxa representing all the major radiations of marsupials and 10 outgroups, most of which are exceptionally well-preserved fossils such as Vincelestes , Ukhaatherium , and a few basal metatherian taxa, were investigated. A maximum parsimony analysis was conducted, resulting in one most parsimonious tree. Relationships among outgroups are congruent with current understanding of mammalian phylogeny. All currently accepted marsupial orders were recovered by the analysis. We confirmed previous results showing the South American “monito del monte” Dromiciops nested within the Australasian radiation. Within this australidelphian clade, Dromiciops was closely allied with the Diprotodontia. The South American paucituberculates appeared more closely related to the Australidelphia than to the American Didelphimorphia. The marsupial mole Notoryctes and the Peramelia were closely allied to each other and in turn were the sister group of the Dromiciops plus Diprotodontia clade. This pattern of relationships left Dasyuromorphia as the most basal offshoot of the Australidelphia. Whereas this tree topology recovers some signal that had been detected by previous studies, morphological and/or molecular, some novel hypotheses are also supported.
Potentiation of parkinsonian symptoms by depletion of locus coeruleus noradrenaline in 6‐hydroxydopamine‐induced partial degeneration of substantia nigra in rats
2003-06-01

Abstract Parkinson's disease is characterized not only by a progressive loss of dopaminergic neurons in the substantia nigra but also by a degeneration of locus coeruleus noradrenergic neurons. The present study addresses the question of whether a partial neurodegeneration of dopaminergic neurons using 6‐hydroxydopamine in rat, not sufficient to produce motor disturbances, is potentiated by prior selective denervation of locus coeruleus noradrenergic terminal fields using N‐ethyl‐2‐bromobenzylamine. Two types of denervations, one causing dopamine deficiency alone and the other causing noradrenaline and dopamine deficiency, were performed. Noradrenaline, 5‐hydroxytryptamine, 5‐hydroxyindole acetic acid, dopamine and its metabolites were analysed in various brain regions. Behaviour was evaluated by catalepsy tests and activity box. N‐ethyl‐2‐bromobenzylamine selectively depleted noradrenaline from neurons of locus coeruleus origin. Decreased dopamine content in the striatum, substantia nigra and pre‐frontal cortex was observed after dopaminergic lesion with 6‐hydroxydopamine (42.9%). Additional locus coeruleus noradrenaline depletion with N‐ethyl‐2‐bromobenzylamine aggravated the dopamine depletion (61.2%). The lesion in the noradrenergic and dopaminergic neurodegenerated group was not sufficient to induce consistent catalepsy and akinesia. However, after a subthreshold dose of haloperidol (0.1 mg/kg), the expression of catalepsy and akinesia was strong in the dual‐lesioned group and less in the 6‐hydroxydopamine‐lesioned group. These results indicate that denervation of locus coeruleus noradrenergic terminals with N‐ethyl‐2‐bromobenzylamine potentiates the 6‐hydroxydopamine‐induced partial dopaminergic neurodegeneration and parkinsonian symptoms. Based on the present findings and existing reports, it can be concluded that noradrenergic neurons of locus coeruleus have neuromodulatory and neuroprotective properties on the dopaminergic neurons of basal ganglia and that noradrenergic degeneration may contribute to the aetiology and pathophysiology of Parkinson's disease.
Identification of a basolateral Cl−/HCO 3 − exchanger specific to gastric parietal cells
2003-06-01

The basolateral Cl − /HCO[Formula: see text] exchanger in parietal cells plays an essential role in gastric acid secretion mediated via the apical gastric H + -K + -ATPase. Here, we report the identification of a new Cl − /HCO[Formula: see text]exchanger, which shows exclusive expression in mouse stomach and kidney, with expression in the stomach limited to the basolateral membrane of gastric parietal cells. Tissue distribution studies by RT-PCR and Northern hybridizations demonstrated the exclusive expression of this transporter, also known as SLC26A7, to stomach and kidney, with the stomach expression significantly more abundant. No expression was detected in the intestine. Cellular distribution studies by RT-PCR and Northern hybridizations demonstrated predominant localization of SLC26A7 in gastric parietal cells. Immunofluorescence labeling localized this exchanger exclusively to the basolateral membrane of gastric parietal cells, and functional studies in oocytes indicated that SLC26A7 is a DIDS-sensitive Cl − /HCO[Formula: see text] exchanger that is active in both acidic and alkaline pH i . On the basis of its unique expression pattern and function, we propose that SLC26A7 is a basolateral Cl − /HCO[Formula: see text] exchanger in gastric parietal cells and plays a major role in gastric acid secretion.
Training locked-in patients: a challenge for the use of brain-computer interfaces
2003-06-01

Training severely paralyzed patients to use a brain-computer interface (BCI) for communication poses a number of issues and problems. Over the past six years, we have trained 11 patients to self-regulate their slow cortical brain potentials and to use this skill to move a cursor on a computer screen. This paper describes our experiences with this patient group including the problems of accepting and rejecting patients, communicating and interacting with patients, how training may be affected by social, familial, and institutional circumstances, and the importance of motivation and available reinforcers.
Lymphatic vessels in the colonic mucosa in ulcerative colitis.
2003-06-01

In the normal colonic mucosa, lymphatics are found only in a narrow band associated with the muscularis mucosae and are absent from the rest of the mucosa. This study examined whether this arrangement of lymphatics is also valid in ulcerative colitis. Histological sections of colon from 15 long-standing cases were investigated with antibodies against CD 34 (negative for lymphatics; positive for blood vessel endothelium) and, in selected cases, podoplanin (positive for lymphatic endothelium; negative for blood vessel endothelium). Whereas inflammation of the mucosa was not associated with changes in lymphatics, an increase in intramucosal lymphatics was seen when the pathological changes included widening of the muscularis mucosae or penetration of the mucosa by muscle fibers, filiform changes in the mucosa, and hyperplasia of the mucosa-associated lymphoid tissue (MALT). In specimens with epithelial dysplasia, an association between the dysplastic epithelium and ectatic and quantitatively increased lymphatics was observed. With superimposed carcinoma, no relationship between the malignant tumor and lymphatics was identifiable. Nevertheless, pre-existing lymphatics in the muscularis mucosae were involved in lymphatic tumor spread. The immunohistochemical findings demonstrated that lymphatics occurred in all areas of the mucosa in ulcerative colitis (or, in effect, at sites which were not normally found under physiological conditions) and in regions that favored lymphatic tumor dissemination. Whether these lymphatics were actually involved in metastasis remains to be defined.
In-situ biodegradation of tetrachloroethene and trichloroethene in contaminated aquifers monitored by stable isotope fractionation
2003-06-01

Stable carbon isotope analysis of tetrachloroethene (PCE) and trichloroethene (TCE) was applied to evaluatenatural attenuation processes in the upper Quaternary and lower Tertiary aquifer in the area of a former dry-cleaning plant located in Leipzig, Germany. Groundwater samples were taken during one monitoring campaign in 2001. The 13C enrichment in contaminants along the water flow path suggested that both, PCE and TCE were degraded in the Quaternary aquifer. The enrichment of 13C in the residual PCE fraction and an isotope fractionation factor from laboratory experiments were used to calculate the extent of biodegradation in the Quatemary aquifer. These calculations indicated that a major portion of PCE was biodegraded in the course of the plume. In the Tertiary aquifer the carbon isotope ratios of PCE and TCE indicated that the decreasing concentrations of these contaminants were probably not caused by microbial processes.
Fibroblast growth factor‐2 but not Mel‐CAM and/or β3 integrin promotes progression of melanocytes to melanoma
2003-06-01

Abstract: A variety of melanoma‐associated antigens have been identified that mediate adhesion, growth, proteolysis, and modulation of immune response. However, the mechanisms by which human normal melanocytes become malignant are not clearly understood. Among the most consistent observations is the up‐regulation of fibroblast growth factor‐2 (FGF‐2) and of the adhesion molecules β3 integrin and Mel‐CAM during melanoma progression. To evaluate the potential role of FGF‐2, β3 integrin and Mel‐CAM in melanoma development we overexpressed FGF‐2, β3 integrin and Mel‐CAM in normal human melanocytes using replication‐deficient adenoviruses as a gene delivery vehicle. Fibroblast growth factor‐2 overexpressing melanocytes in monolayer culture displayed cytological atypia. Furthermore, in human skin reconstructs where the physiological milieu is recreated in vitro , FGF‐2‐overexpressing melanocytes exhibited marked proliferation, upwards migration, cluster formation and type IV collagen expression within the epidermal compartment, simulating early radial growth phase melanoma. In contrast, overexpression of β3 integrin and/or Mel‐CAM in melanocytes did not affect their biological behaviour in human skin reconstructs. The described results of the current and previous studies emphasise the key role of FGF‐2 in melanoma development and progression, underscoring the promise of FGF‐2 as a target for therapy.
Two dimensional superconducting quantum interference filters
2003-06-01

We have successfully developed a novel superconducting quantum interferometer based on Josephson junction networks with unconventional loop size distribution. For distinct theoretically determined distributions, the magnetic field B dependent dc voltage V(B) of the interferometer possesses a unique delta-peak like characteristics around B=0. Such devices are called Superconducting Quantum Interference Filters (SQIFs). The unique voltage response of SQIFs allows novel applications, e.g., absolute magnetic field sensors, high speed logical switches and non hysteretic low noise amplifiers which can be directly connected to standard room temperature electronics. In this paper we present new experimental and theoretical results on high performance two dimensional Superconducting Quantum Interference Filters (2D SQIFs). Such 2D SQIFs can be used as absolute magnetic field sensors. Our results indicate that due to the scaling behavior of the flux to voltage transfer function and the scaling of the white output noise, a highly sensitive absolute field sensor based on 2D SQIFs can be very small in size.
MR imaging and spectroscopy of a tuber cinereum hamartoma in a patient with growth hormone deficiency and hypogonadotropic hypogonadism.
2003-06-01

Summary: To our knowledge, this is the first report of hypogonadotropic hypogonadism, or growth hormone deficiency, in a patient without non-Pallister-Hall syndrome who had hypothalamic hamartoma diagnosed on the basis of MR imaging and MR spectroscopy findings. On short-TE proton MR spectra, the N-acetylaspartate concentration in the hamartoma was lower than that in the thalamus but similar to that in the amygdala. However, myo-inositol concentration was elevated in the hamartoma compared with that in the amygdala and thalamus. This report stresses the advantages of short-TE spectroscopy and demonstrates that regional variations in spectra should be considered when reference structures are used.
Startle Response Modulation as a Behavioral Tool in Neuropharmacology
2003-06-01

Behavioral studies in animals are an important part of neuropharmacological research, because they integrate findings from in vitro pharmacology, chemical neuroanatomy and electrophysiology at the systems level, thereby bridging the gap between basic research on one hand, and the development of pharmacological treatment with clinical trials on the other hand. Animal behavioral models of neuropsychiatric diseases (such as fear/anxiety disorders, depression, addiction, or schizophrenia) are, therefore, an eminent part of preclinical neuropharmacology. We review here recent neuropharmacological findings on prepulse inhibition (PPI) and fear-potentiation of the startle response (FPS) as behavioral models for sensorimotor gating deficits in neuropsychiatric disorders and fear/anxiety-related disorders, respectively. Keywords: anxiety, fear, fear-potentiated startle, prepulse inhibition, schizophrenia
Cytokines and Antitumor Immunity
2003-06-01

Currently, the notion of immunosurveillance against tumors is enjoying something of a renaissance. Even if we still refuse to accept that tumors arising in the normal host are unable to trigger an immune response because of the lack of initiation (“danger”) signals, there is no doubt that the immune system can be manipulated experimentally and by implication therapeutically to exert anti-tumor effects. For this activity to be successful, the appropriate cytokine milieu has to be provided, making cytokine manipulation central to immunotherapy. On the other hand, the major hurdle currently preventing successful immunotherapy is the ability of tumors to evolve resistant variants under the pressure of immune selection. Here, too, the cytokine milieu plays an essential role. The purpose of this brief review is to consider the current status of the application of cytokines in facilitating antitumor immunity, as well their role in inhibiting responses to tumors. Clearly, encouraging the former but preventing the latter will be the key to the effective clinical application of cancer immunotherapy.
Metabolic Effects of the Gly1057Asp Polymorphism in IRS-2 and Interactions With Obesity
2003-06-01

Insulin receptor substrate (IRS)-2 plays an important role in insulin signaling and its disruption results in diabetes in mice. In humans, the IRS-2 Gly1057Asp substitution was associated with lower risk of type 2 diabetes in lean individuals, but with a higher risk in obese individuals. To clarify the role of IRS-2 on the development of type 2 diabetes and obesity in Pima Indians, and particularly to investigate whether the effects of the Gly1057Asp polymorphism on metabolism are mediated by obesity, molecular scanning of the gene for mutations was performed and interaction of the polymorphism with obesity was tested. We identified the previously described Gly1057Asp mutation as well as a rare Asp819His mutation and four silent polymorphisms. The effect of the Gly1057Asp mutation on type 2 diabetes and obesity was tested in a large cohort of Pima Indians (n = 998). A subgroup of nondiabetic full-heritage Pima Indians (n = 233) had measurements of body composition, glucose tolerance, insulin action (M), endogenous glucose production (EGP; hyperinsulinemic clamp), acute insulin response (AIR, 25-g intravenous glucose tolerance test, n = 118 normal glucose-tolerant subjects), and percutaneous fat biopsy specimens from the periumbilical region (n = 160). A total of 132 nondiabetic subjects were included in longitudinal analyses. The frequency of the Asp1057 allele was 0.6. In cross-sectional analyses, subjects homozygous for the Asp1057 allele (Asp/Asp) had a higher prevalence of type 2 diabetes than heterozygote individuals and subjects homozygous for the Gly1057 allele (X/Gly, P = 0.04). There was no effect on BMI (P = 0.78) or gene-BMI interaction on the prevalence of type 2 diabetes (P = 0.57). In the nondiabetic subgroup, subjects with Asp/Asp had higher percent body fat (P = 0.01), BMI (P = 0.02), and waist circumference (P = 0.004), but there was no difference in metabolic characteristics (all P &amp;gt; 0.2). However, the relationship between percent body fat and fasting glucose, basal EGP, EGP during the clamp, AIR, and subcutaneous abdominal adipocyte size was significantly different in the Asp/Asp group (P for interaction = 0.02, 0.06, 0.0007, 0.08, and 0.006, respectively) compared with the X/Gly group, suggesting a more detrimental effect of Asp homozygosity on these traits with increasing percent body fat. In longitudinal analyses, among subjects in the upper tertile of change in percent body fat, those with Asp/Asp had a larger increase in fasting and postprandial glycemia and basal EGP and a larger decrease in M and AIR than subjects with X/Gly, independent of change in obesity (all P &amp;lt; 0.05). In conclusion, our findings suggest that the association of homozygosity for the Asp1057 allele in IRS-2 with type 2 diabetes in Pima Indians may be mediated by interaction of the polymorphism with obesity on several diabetes-related traits.
MR Imaging–Guided Adrenal Biopsy Using an Open Low-Field-Strength Scanner and MR Fluoroscopy
2003-06-01

MR imaging-guided biopsy of the adrenal gland is feasible and safe. In all patients, appropriate specimens were obtained with full diagnostic yield and accuracy. MR fluoroscopy is particularly useful to establish an oblique paravertebral access without pleural transgression. For final needle placement, supplementary breath-hold multislice sequences are required in most cases.
Looking into the water with oblique head tilting: revision of the aerial binocular imaging of underwater objects
2003-06-01

It is a well-known phenomenon that when we look into the water with two aerial eyes, both the apparent position and the apparent shape of underwater objects are different from the real ones because of refraction at the water surface. Earlier studies of the refraction-distorted structure of the underwater binocular visual field of aerial observers were restricted to either vertically or horizontally oriented eyes. We investigate a generalized version of this problem: We calculate the position of the binocular image point of an underwater object point viewed by two arbitrarily positioned aerial eyes, including oblique orientations of the eyes relative to the flat water surface. Assuming that binocular image fusion is performed by appropriate vergent eye movements to bring the object's image onto the foveas, the structure of the underwater binocular visual field is computed and visualized in different ways as a function of the relative positions of the eyes. We show that a revision of certain earlier treatments of the aerial imaging of underwater objects is necessary. We analyze and correct some widespread erroneous or incomplete representations of this classical geometric optical problem that occur in different textbooks. Improving the theory of aerial binocular imaging of underwater objects, we demonstrate that the structure of the underwater binocular visual field of aerial observers distorted by refraction is more complex than has been thought previously.
Automated RNA Extraction by MagNA Pure Followed by Rapid Quantification of Cytokine and Chemokine Gene Expression with Use of Fluorescence Resonance Energy Transfer
2003-06-01

Cytokines and chemokines, a superfamily of small cytokine-like molecules, are key mediators of immunity and inflammation. Detection of cytokines and chemokines in disease states provides useful diagnostic tools for investigating host responses to invading organisms, tumors, and trauma. Different reverse transcription-PCR (RT-PCR) protocols have been described in the literature, including semiquantitative, quantitative, and competitive PCR techniques, but most of them were labor-intensive and time-consuming (1)(2). Recently, real-time PCR assays have become a major tool for quantifying the number of DNA or cDNA copies in different settings and clinical materials. These assays offer a standardized, rapid, accurate, and reproducible method that combines rapid in vitro amplification with real-time quantification of the DNA or cDNA load. However, to date, only limited data are available for quantification of cytokine gene expression (3)(4). In addition, there is a need for rapid, sensitive, reliable, and standardized methods for RNA extraction. Here we present an automated standardized protocol for the extraction of RNA from human peripheral blood mononuclear cells (PBMCs), using the MagNA Pure LC system (Roche Diagnostics), combined with a rapid and easy-to-perform quantitative PCR assay, using the LightCycler (Roche Diagnostics) amplification and detection system. We applied this protocol to quantification of mRNA expression of the following immunorelevant genes: interleukin (IL)-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p40, IL-18, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), macrophage-inducing protein-3α (MIP-3α), SCYB-11 (IFN-inducible T-cell-α chemoattractant; H174; CXCL11), intracellular adhesion molecule-1 (ICAM-1; CD54), and nuclear factor-κB (NFκB), the transcription factor and central mediator of immune response. PBMCs were prepared from 50 mL of heparinized fresh venous blood obtained from healthy donors (n = 30). PBMCs were separated by centrifugation over Ficoll and resuspended in 1 mL of phosphate-buffered saline. The PBMC concentration was adjusted to 1 × 106/mL in RPMI 1640 containing 100 ...
Direct effects on proliferation, antigen expression and melanin synthesis of cultured normal human melanocytes in response to UVB and UVA light
2003-06-01

Background/Purpose: Ultraviolet (UV) radiation; induces a variety of responses in the skin, including tanning and inflammation, and may also act as a carcinogen. As epidermal melanocytes are seen as the major targets of UV light, the present study was conducted to evaluate the direct effects of UVA and UVB irradiation on melanocytes in vitro . Methods: Normal human epidermal melanocytes (NHM) were exposed on 3 consecutive days to UVA (0.072–7.2 J/cm 2 ) and UVB (7.2–48 mJ/cm 2 ), respectively, and changes of morphology, cell number, melanin synthesis and antigen expression (APAAP technique) were determined 5 days after the first exposure. Results: UVA radiation caused only minimal effects on NHM by slightly inducing expression of the activation marker HMB‐45 and decreasing expression of the proliferation marker Ki‐67. No changes of morphology, cell number or melanin synthesis were detectable with any of the applied doses. On the other hand, UVB radiation significantly induced dendrite formation and decreased the number of NHM in a dose‐dependent manner (74% of the controls at 7.2 mJ/cm 2 , 64% at 14.4 mJ/cm 2 and 28% at 36 mJ/cm 2 ). Significant induction of the activation marker HMB‐45 was found in parallel to decreased expression of the differentiation marker K.1.2.58. UVB doses 9.6 mJ/cm 2 also resulted in significant downregulation of the proliferation marker Ki‐67, confirming the data of the cell counts, and melanin content was increased in NHM (20% over the controls, P &lt;0.01) after applying 7.2 mJ/cm 2 UVB. Conclusion: Our results may suggest that the effect of UVB radiation in skin is due to direct activation of melanocytes, whereas skin tanning caused by UVA is mediated rather in an indirect way.