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1.
Strongyle faecal egg output was estimated in N'Dama, Zebu and N'Dama x Zebu crossbred (F1) cattle. N'Dama cattle showed a significantly lower prevalence of strongyle infection, as measured by faecal egg output, than F1 (P < 0.01) and Zebu (P < 0.001) cattle. In strongyle-infected animals, mean egg output was also significantly lower in N'Damas (P < 0.03) than in Zebus. A previous trypanosomiasis infection did not affect the results. The presence of a natural resistance trait to strongyle infection in N'Dama cattle is postulated.  相似文献   
2.
The presence of glucocorticoid receptors (GR) in rat liver nuclei over a 24 h time period following hyperthermic stress at 41 degrees C was immunocytologically studied using unfixed nuclear smears. Liver nuclei in unstressed animals were found to be immunonegative for GR. However, intense GR immunopositivity followed by a subsequent gradual decrease in receptor levels was observed in the nuclei of test animals during the first 2 h after stress. This stress-related increase in the receptor nuclear level was greater than the increase seen after dexamethasone administration. These results suggest that hyperthermic stress could potentiate the hormonal stimulation of receptor nuclear translocation.  相似文献   
3.
The epidermal growth factor-seven transmembrane (EGF-TM7) family is a group of seven-span transmembrane receptors predominantly expressed by cells of the immune system. Family members CD97, EGF module-containing mucin-like receptor (EMR) 1, EMR2, EMR3, EMR4, and EGF-TM7-latrophilin-related protein are characterized by an extended extracellular region with a variable number of N-terminal EGF-like domains. EGF-TM7 receptors bind cellular ligands as demonstrated by the interaction of CD97 with decay accelerating factor (CD55) and dermatan sulfate. Investigating the effect of newly generated mAb on the migration of neutrophilic granulocytes, we here report for the first time in vivo data on the function of CD97. In dextran sulfate sodium-induced experimental colitis, we show that homing of adoptively transferred neutrophils to the colon was significantly delayed when cells were preincubated with CD97 mAb. The consequences of this defect in neutrophil migration for host defense are demonstrated in a murine model of Streptococcus pneumoniae-induced pneumonia. Mice treated with CD97 mAb to EGF domain 1 (1B2) and EGF domain 3 (1C5) displayed a reduced granulocytic inflammatory infiltrate at 20 h after inoculation. This was associated with a significantly enhanced outgrowth of bacteria in the lungs at 44 h and a strongly diminished survival. Together, these findings indicate an essential role for CD97 in the migration of neutrophils.  相似文献   
4.
We report on a 9-year-old female patient presenting with muscle weakness, facial dysmorphism and mild mental retardation. She had low birth weight, developmental delay, hypotonia and hyporeflexia and difficulties in climbing the stairs. EMG revealed axonal polyneuropathy affecting both upper and lower limbs. She was the child of non-consanguineous parents, her cytogenetic findings revealed 46,XX,t(12;14)(q14;q23). The mother's karyotype was normal 46,XX while the father's karyotype was 46,XY,t(12;14)(q14;q23) the same as his daughter. Her normal sister's karyotype was also 46,XX,t(12; 14) (q14;q23). Fluorescence in situ hybridization (FISH) was used to elucidate the breakpoints and Array-CGH was done for the patient to confirm the balanced translocation. This observation is of interest because it represents a rare case of a balanced translocation with abnormal phenotype. Mutant genes causing axonal neuropathy have been located on various chromosomes other than 12q14 or 14q24. This report shows the importance of molecular cytogenetics and its correlation with abnormal phenotype and the possibility of another gene locus at the presently studied chromosomal breakpoints. Detailed correlations between chromosome aberrations and their phenotypes are of invaluable help in localising genes for axonal polyneuropathy.  相似文献   
5.
This paper shows a protocol for the detection of ZAP-70 expression in B-CLL (B cell chronic lymphocytic leukemia) tumor cells by common immunohistochemical methods. The study was conducted on bone marrow trephine biopsies from 62 B-CLL patients at the time of diagnosis. Immunohistochemical reactions based on peroxidase and alkaline phosphatase reactions were used, as well as double immunofluorescent labeling for ZAP-70 detection as an indirect marker of mutated and unmutated CLL. Clinical relevance of the ZAP-70 expression detection method was assessed using χ 2 test between ZAP-70 positivity data and other known prognostic factors, i.e., clinical and cytogenetics data. ZAP-70 was detected in 13 out of 62 patients. Statistically significant results were obtained for ZAP-70 positive cases and known indicators of worse prognosis. Immunohistochemical analysis supported by double immunfluorescent labeling, as shown here, is an easy and reliable technique for the detection of ZAP-70 expression in B-CLL tumor cells applicable in every hematopathology laboratory.  相似文献   
6.
Summary The functional morphology of the neuroendocrine system producing sodium influx-stimulating (SIS) peptide in the pond snail, Lymnaea stagnalis, was studied by in situ hybridization and immunocytochemistry. The SIS-peptide, which is 76 amino acids long, stimulates sodium uptake from the ambient medium. Two synthetic DNA probes were used for in situ hybridization. The nucleotide sequences were chosen from the cDNA structure; they encode amino acids 8–17 and 64–73, respectively. SIS-peptide sequences 10–20 and 67–76 were synthesized and antibodies were raised to them and affinity-purified. In addition to these antibodies, a monoclonal antibody raised to a bioactive, high-pressure liquid chromatography (HPLC)-purified brain extract was used for immunocytochemistry. Paraffin sections of central nervous systems and of whole snails were studied. The SIS-peptide system could be identified as the previously described yellow cell (YC) system by comparing alternate sections treated with the DNA probes, stained with the antibodies, or stained with alcian blue-alcian yellow. SIS-peptide neurons (45) occur in the ganglia of the visceral ring and in the proximal parts of visceral nerves. Axons run in the nerves of these and in several nerves of other ganglia. Numerous axon branches penetrate the perineurium forming a vast central neurohemal area. The SIS-peptide system innervates the pericardium, the nephridial gland, the reno-pericardial canal, the ureter, the spermoviduct and gonadal acini, the anterior aorta, the ventral buccal artery, and the penis protractor muscle. The morphology of the system is discussed in relation to the process of sodium ion uptake from the ambient medium and from pro-urine, and to that of regulating blood pressure. In the central nervous system and other organs, neurons and axons not labeled with the DNA probes, but immunoreactive to one or two of the antibodies, were observed. It seems unlikely that these elements are functionally related to the SIS-peptide system.  相似文献   
7.
Summary The Upper Cretaceous exposures in east central Sinai are represented by carbonate-dominated successions interbedding few sandstone, chert, shale and marl horizons. The recognised rock units are correlated with their counterparts commonly used in the Gulf of Suez region and central Sinai including from base to top: the Raha Formation, Abu Qada Formation, Wata Formation, Matulla Formation and the Sudr Chalk. Twelve limestone microfacies are encountered and are categorised as mudstones (pelmicrite and ostracod micrite), wackestones (pelagic biomicrite and foraminiferal biomicrite), grainstones (foraminiferal biopelsparite and oosparite), boundstones (bindstone and framestone), floatstones (coated-grained biomicrudite, rudist biomicrudite and shelly biomicrudite) and rudstones (shelly biosparudite). The dolostone microfacies include fine-medium crystalline ostracod dolostones and shelly dolostones. These microfacies have been compared with the Standard Microfacies Types and their depositional environments are discussed. The encountered litho- and biofacies suggest that the Cenomanian shallow transgressive sea had covered east central Sinai as far south as the Dahab region. By the advent of the Turonian, open marine subtidal conditions prevailed. This was followed by transitional conditions with shoals and tidal bars in the Late Turonian pointing to a regressive phase more pronounced at the southern localities. The rocks of the Matulla Formation were deposited in an oscillating environment of shallow subtidal to intertidal conditions during Coniacian-Santonian. In the Late Santonian and during most of the Campanian-Maastrichtian, sedimentation was influenced by open marine conditions with low sedimentation rates; local shallow subtidal regressive events occurred.  相似文献   
8.

Background

Wolfram syndrome (WFS) is a recessive neurologic and endocrinologic degenerative disorder, and is also known as DIDMOAD (Diabetes Insipidus, early-onset Diabetes Mellitus, progressive Optic Atrophy and Deafness) syndrome. Most affected individuals carry recessive mutations in the Wolfram syndrome 1 gene (WFS1). However, the phenotypic pleiomorphism, rarity and molecular complexity of this disease complicate our efforts to understand WFS. To address this limitation, we aimed to describe complications and to elucidate the contributions of WFS1 mutations to clinical manifestations in Japanese patients with WFS.

Methodology

The minimal ascertainment criterion for diagnosing WFS was having both early onset diabetes mellitus and bilateral optic atrophy. Genetic analysis for WFS1 was performed by direct sequencing.

Principal Findings

Sixty-seven patients were identified nationally for a prevalence of one per 710,000, with 33 patients (49%) having all 4 components of DIDMOAD. In 40 subjects who agreed to participate in this investigation from 30 unrelated families, the earliest manifestation was DM at a median age of 8.7 years, followed by OA at a median age of 15.8 years. However, either OA or DI was the first diagnosed feature in 6 subjects. In 10, features other than DM predated OA. Twenty-seven patients (67.5%) had a broad spectrum of recessive mutations in WFS1. Two patients had mutations in only one allele. Eleven patients (27.5%) had intact WFS1 alleles. Ages at onset of both DM and OA in patients with recessive WFS1 mutations were indistinguishable from those in patients without WFS1 mutations. In the patients with predicted complete loss-of-function mutations, ages at the onsets of both DM and OA were significantly earlier than those in patients with predicted partial-loss-of function mutations.

Conclusion/Significance

This study emphasizes the clinical and genetic heterogeneity in patients with WFS. Genotype-phenotype correlations may exist in patients with WFS1 mutations, as demonstrated by the disease onset.  相似文献   
9.
Alterations of pancreatic antioxidative defense (AD) and possible nitric oxide (NO) role in AD organization of adult rats receiving l-arginine.HCl (2.25%) or N(omega)-nitro-l-arginine methyl ester (L-NAME.HCl, 0.01%) as drinking liquids and maintained at room (22+/-1 degrees C) or low (4+/-1 degrees C) temperature for 45 days were studied. For that purpose, copper, zinc- and manganese superoxide dismutase (CuZnSOD, MnSOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione S-transferase (GST) and glutathione reductase (GR) activities were determined. Cold-induced decrease of CuZnSOD was inhibited with L-NAME, while l-arginine produced the same effect as cold in both supplemented groups. Cold acclimation elevated GSH-Px activity. l-Arginine and L-NAME expressed no effect on GSH-Px in rats kept at room temperature. L-NAME additionally elevated cold-induced GSH-Px activity, l-arginine expressing a similar trend. Cold-induced increase in GST activity was inhibited by L-NAME, while l-arginine inhibited this enzyme in both supplemented groups. Cold acclimation increased GR activity in control and L-NAME-treated group and l-arginine expressed a similar trend. Neither of the treatments affected MnSOD and CAT activities. Cold-induced changes of pancreatic AD were additionally affected by the alterations in l-arginine-NO-producing pathway. Some AD changes in the same direction with l-arginine or L-NAME point to the complexity of nitrogen compounds metabolism and function, accompanied by tissue-specific response.  相似文献   
10.
Interactions between the aromatic amino acid residues have a significant influence on the protein structures and protein-DNA complexes. These interactions individually provide little stability to the structure; however, together they contribute significantly to the conformational stability of the protein structure. In this study, we focus on the four aromatic amino acid residues and their interactions with one another and their individual interactions with the four nucleotide bases. These are analyzed in order to determine the extent to which their orientation and the number of interactions contribute to the protein and protein-DNA complex structures.  相似文献   
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