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51.
A case of multiple myeloma diagnosed by fine-needle aspiration (FNA) biopsy and confirmed by laboratory studies in a patient with a history of renal-cell carcinoma is presented. The patient was diagnosed with renal-cell carcinoma of the right kidney and a radical nephrectomy was performed. Eighteen months after this diagnosis was made, the patient developed chest wall pain and was found to have osteolytic bone lesions of the ribs and vertebral bodies. FNA of an osteolytic rib lesion disclosed multiple myeloma. Additional laboratory studies confirmed the diagnosis of multiple myeloma. This case report demonstrates the value of FNA as a diagnostic tool for the follow-up of cancer patients, the subsequent discrimination between metatastic lesions and a second primary malignancy, and the cytology of multiple myeloma.  相似文献   
52.
It is increasingly recognized that the identification of t(11;22)(q24;q12) is a useful aid in the accurate diagnosis of Ewing's sarcoma and related tumours. However, cytogenetic studies have a low success rate and adequate tumour is not always available. This study describes the use of fluorescence in situ hybridization (FISH) to detect translocations at 22q12, the site of the EWS gene involved in t(11;22)(q24;q12), on tumour touch imprints made from true cut core-needle biopsy and frozen tumour. Of the seven tumours analysed, five diagnosed as Ewing's sarcoma or primitive neuroectodermal tumour demonstrated chromosome translocation at 22q12. This is a rapid and reliable method to detect a diagnostically relevant chromosome translocation using minimal amounts of fresh or frozen tumour.  相似文献   
53.
The present study utilizes the scanning electron microscope (SEM) to reveal the surface morphology of proximal tubular cells and the parietal cells of Bowman's capsule of the adult rabbit nephron. To facilitate the examination of the basal surface of these cells, proximal tubules were dissected free and treated with collagenase to remove the basememt membrane. Other blocks of tissue were cryofractured to expose the lateral cell surfaces of the proximal tubules. Our investigation has shown that the lateral and basal surfaces of both the convoluted and straight segments of the proximal tubule have numerous processes. However, the arrangement and degree of branching is distinctly different in the two segments. The convoluted segment has large lateral ridges which form at the base of the microvilli and fan out to divide into lateral-basal processes. Many of the lateral-basal processes reach the basement membrane intact, interdigitating with complementary processes from adjacent cells. However, some of the lateral-basal processes branch into short, knobby projections (basal villi) which may also reach the basement membrane. Patches of basal villi are interspersed between broad regions of interdigitating lateralbasal processes. Therefore, in the convoluted segment, the lateral-basal processes form the major part of the basal cell surface. In tubular cells of the pars recta, unlike convoluted tubular cells, the majority of the ridges remain unbranched and pass directly to the basal surface where they divide into elaborate basal villi. Thus the basal surface of the pars recta cells is highly complex, appearing leaf-like, being a composite of numerous basal villi with a few lateral ridges. The basal surface of some parietal cells of Bowman's capsule have parallel ridges, which results in patches of striations.  相似文献   
54.
Summary Some patients with hereditary nephritis (HN) who have received a renal transplant have been shown to form antibody with specificity for the NC1 domain of collagen type IV, a major constituent of glomerular basement membranes (GBM). We attempted to duplicate this phenomenon in a family of dogs with X-linked HN, a model for human X-linked HN, by immunizing affected male dogs with normal dog NC1 domain. A collagenase digest was prepared from normal dog GBM, the NC1 domain was separated into dimer (50 kDa) and monomer (24 kDa and 26 kDa) components by SDS-PAGE, and injected into two affected male dogs. Antisera obtained from both dogs contained antibody which reacted with the NC1 domain of dog and human GBM by a plate-binding radioimmunoassay, bound to the dimer and 26 kDa monomer bands by Western blotting, and staining dog and human GBM by immunofluorescence (IF). The affected male dog antiserum reacted equally by radioimmunoassay with the NC1 domain isolated from GBM of unaffected, affected male, and carrier female dogs in the family with X-linked HN, and bound by Western blotting to dimers and the 26 kDa monomer band of the NC1 domain of GBM in each group of dogs. However, the affected male dog antiserum differentiated these dogs by IF; it produced global staining of GBM of unaffected dogs, failed to stain GBM of affected male dogs, and produced segmental staining of GBM of carrier female dogs. Absorption of the affected male dog antiserum with normal dog NC1 domain eliminated the staining of dog GBM by IF, whereas staining persisted after absorption with affected male dog NC1 domain. The abnormal staining patterns of GBM seen by IF in the affected male and carrier female dogs and the results of the absorption studies imply an abnormality of one or more determinants in the 26 kDa monomer band of the NC1 domain of their GBM. Amino acid sequencing of this band identified the 1(IV) chain of collagen type IV, a finding that has implications for the pathogenesis of canine X-linked HN. Absent and segmental staining respectively were also seen by IF in GBM of a male and female patient with HN, using the affected male dog antiserum. Thus, the results obtained in affected male and carrier female dogs with X-linked HN may also be relevant to patients with this disease.  相似文献   
55.
Cystic fibrosis: Synthesis of ciliary inhibitor by amniotic cells   总被引:1,自引:0,他引:1  
The presence of a ciliary inhibitor in media of cultured amniotic cells obtained from a fetus heterozygous for cystic fibrosis has been observed by the oyster gill cilia assay. The chromatographic fraction containing the inhibitor corresponded to eluted fractions chromatographed from cystic fibrosis fibroblast media and serum. An analogous chromatographic fraction from media of cultured amniotic cells from two proportedly normal fetuses did not inhibit cilia. The chromatographic fraction from media of cultured amniotic cells of a fetus at high risk for cystic fibrosis did not inhibit ciliary activity. Serum was collected from this baby seven weeks after birth and also did not inhibit ciliary action, indicating a homozygous normal genotype. These observations may lead to the development of an antenatal test for cystic fibrosis.  相似文献   
56.
SNP rs498055 in the predicted gene LOC439999 on chromosome 10 was recently identified as being strongly associated with late-onset Alzheimer disease (LOAD). This SNP falls within a chromosomal region that has engendered continued interest generated from both preliminary genetic linkage and candidate gene studies. To independently evaluate this interesting candidate SNP we examined four independent datasets, three family-based and one case-control. All the cases were late-onset AD Caucasian patients with minimum age at onset ≥ 60 years. None of the three family samples or the combined family-based dataset showed association in either allelic or genotypic family-based association tests at p < 0.05. Both original and OSA two-point LOD scores were calculated. However, there was no evidence indicating linkage no matter what covariates were applied (the highest LOD score was 0.82). The case-control dataset did not demonstrate any association between this SNP and AD (all p-values > 0.52). Our results do not confirm the previous association, but are consistent with a more recent negative association result that used family-based association tests to examine the effect of this SNP in two family datasets. Thus we conclude that rs498055 is not associated with an increased risk of LOAD.  相似文献   
57.
To assess the utility of linkage disequilibrium (LD) as a tool for fine-mapping disease genes in non-isolated populations, we have assessed the linkage disequilibrium strength among a series of single nucleotide polymorphisms (SNPs) in an approximate 1 Mb region of human chromosome 22q11. Nineteen random SNPs were discovered and tested across this region with an average spacing of 57 kb (range=1.4-289 kb). These 19 SNPs were genotyped in a population consisting of 444 unrelated pedigrees that were largely collected in the U.S. and U.K. Haplotypes for all pedigrees were derived from pedigree data and over 1,400 haplotypes from unrelated individuals were evaluated for linkage disequilibrium between marker alleles. In addition, linkage disequilibrium between marker alleles was also evaluated using estimated haplotypes without genealogical information (i.e., without parental genotype information). Every marker pair combination was tested for a total of 171 tests and 2x2 contingency tables were constructed to measure LD strength. In general the haplotypes derived from pedigree data provided a more conservative estimate of LD strength. Using genealogical information for estimates of D', 59% (10/17) of marker pairs less than 50 kb apart had D' values >0.30. Finally, we observed a 60 kb region with non-significant LD, which could reflect increased recombination in this region.  相似文献   
58.
Coxsackievirus B3 (CVB3) infection can result in myocarditis, which in turn may lead to a protracted immune response and subsequent dilated cardiomyopathy. Human decay-accelerating factor (DAF), a binding receptor for CVB3, was synthesized as a soluble IgG1-Fc fusion protein (DAF-Fc). In vitro, DAF-Fc was able to inhibit complement activity and block infection by CVB3, although blockade of infection varied widely among strains of CVB3. To determine the effects of DAF-Fc in vivo, 40 adolescent A/J mice were infected with a myopathic strain of CVB3 and given DAF-Fc treatment 3 days before infection, during infection, or 3 days after infection; the mice were compared with virus alone and sham-infected animals. Sections of heart, spleen, kidney, pancreas, and liver were stained with hematoxylin and eosin and submitted to in situ hybridization for both positive-strand and negative-strand viral RNA to determine the extent of myocarditis and viral infection, respectively. Salient histopathologic features, including myocardial lesion area, cell death, calcification and inflammatory cell infiltration, pancreatitis, and hepatitis were scored without knowledge of the experimental groups. DAF-Fc treatment of mice either preceding or concurrent with CVB3 infection resulted in a significant decrease in myocardial lesion area and cell death and a reduction in the presence of viral RNA. All DAF-Fc treatment groups had reduced infectious CVB3 recoverable from the heart after infection. DAF-Fc may be a novel therapeutic agent for active myocarditis and acute dilated cardiomyopathy if given early in the infectious period, although more studies are needed to determine its mechanism and efficacy.  相似文献   
59.
BACKGROUND: Treatment with omalizumab has been shown to reduce serum free IgE concentrations and to have beneficial effects on allergic airway disease. However, its effect on IgE synthesis is unknown. OBJECTIVE: To determine whether omalizumab therapy affects nasal reactivity to allergen and local IgE production. METHODS: Nineteen patients with perennial allergic rhinitis were treated with intravenous omalizumab every 2 weeks for 26 weeks in an open-label study. Serum free and total IgE concentrations were measured at baseline and every 2 weeks throughout the study. Nasal challenge to dust mite allergen was performed at baseline and after 12 and 24 weeks of treatment. Nasal lavage fluid obtained before and after each nasal challenge was evaluated for mite-specific antibodies, plaque-forming cells, and productive epsilon messenger RNA (mRNA). RESULTS: During treatment, serum free IgE concentrations were decreased by 97% to 99%, and the nasal response to allergen challenge was significantly reduced on days 80 and 164. The postchallenge increase in nasal lavage mite specific IgE was significantly reduced by treatment with omalizumab on day 168. IgE plaque-forming cells and productive epsilon mRNA were not significantly affected by omalizumab treatment. CONCLUSIONS: Omalizumab treatment markedly reduced serum free IgE and the clinical response to nasal allergen challenge. However, the absence of an effect on IgE-secreting B cells and epsilon mRNA in nasal lavage fluid suggests that omalizumab treatment for 6 months does not significantly modulate synthesis of nasal IgE.  相似文献   
60.
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