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Cyclic nucleotides are important second messengers that mediate a number of cellular responses to external signals. Cyclic nucleotide phosphodiesterases play a role in signal transduction by regulating the cellular concentrations of these messengers. Here, we have applied Southern analyses of somatic cell hybrid lines and of recombinant inbred (RI) mouse strains as well as fluorescence chromosomal in situ hybridization (FISH) to chromosomally localize five cAMP-specific nucleotide phosphodiesterase genes in human and mouse. GenesDPDE1, DPDE2, DPDE3, andDPDE4 that share sequence homology with theDrosophila dunce gene were assigned to human chromosomes 19 (DPDE1 andDPDE2), 5q12 (DPDE3), and 1p31 (DPDE4) and to mouse chromosomes 8, 9, 13, and 4, respectively. The high-affinity cAMP-specific phosphodiesterase gene (HCP1) was mapped to human chromosome 8q13-q22. Since these genes are potential candidates for involvement in psychiatric or behavioral disorders, knowledge of their chromosomal localizations will facilitate the discovery of their association with disease genes as they are being mapped by linkage studies.  相似文献   
3.
Women need to practice cervical screening regularly to reduce morbidity and mortality. The purpose of this study was to examine the impact of an intervention program on knowledge, attitude, and practice of cervical screening in the population of Lebanese/Armenian women. The design was a cross-sectional, quasi-experimental posttest survey following a year long intervention program. The sample included 176 women, who were members of the Armenian Relief Cross in Lebanon. Interventions consisted of educational classes, media messages, and free screening. The instrument was a self-administered questionnaire. Knowledge of women with intervention was higher (p > .05) and practice rate increased between intervention and comparison groups. No difference in attitude was noted. The study was successful in raising awareness and increasing screening in the sample. It is recommended to continue helping women to overcome barriers for cervical screening.  相似文献   
4.
Circular esophageal myotomy (CEM) is currently a well-accepted technique for elongation of the upper esophageal pouch in cases of long-gap esophageal atresia (EA). Esophageal pseudodiverticulum is a frequent and perhaps underreported sequela of this technique, characterized by ballooning or outpouching of the esophageal mucosa in the myotomized area. The present study was designed to seek a supplement for the CEM technique in order to avoid possible pseudodiverticulum formation in the myotomized area. We created an animal model to simulate the anatomic conditions present after primary repair of EA facilitated by CEM. Three groups of dogs underwent either cervical (1 group) or thoracic (2 groups) esophageal myectomy. In the cervical and first thoracic groups, the denuded mucosa was left without any support. In the second thoracic group, the denuded mucosal area was wrapped with polyglactin 910 (Vicryl) mesh. In all three groups the esophagus was narrowed by a Marlex mesh ring 3 cm distal to the myectomized zone, simulating a condition resulting from anastomotic narrowing. The dogs underwent barium swallows under fluoroscopy at different postoperative periods and were killed 4 or 6 months after surgery. The esophagi were removed for gross and radiologic investigation under maximal insufflation as well as for histologic assessment. The proposed canine model proved to be useful for study of the myectomized esophagus, mimicking the anatomy and conditions after CEM in long-gap EA repair. Wrapping the denuded mucosa with Vicryl mesh fortified the weakened esophageal wall, thus diminishing the likelihood of future pseudodiverticulum development. In light of the simplicity of the technique and the absence of any evident risk or complications, we recommend that the use of Vicryl mesh wrap be considered during CEM to reinforce the esophageal wall.Supported by the Slezak Fund for Experimental Surgery (Grant #01370791)  相似文献   
5.
We present a case of a malignant phyllodes tumor metastasizing to a Hürthle cell adenoma of the thyroid. A 55-year-old woman underwent mastectomy for a malignant phyllodes tumor. Two years later, she presented with a left thyroid mass, which was a single, circumscribed, soft, deep red-brown nodular lesion with an eccentric area of firmer consistency. Histologically, the thyroid tumor was composed of 2 distinct types of cellular proliferation. Atypical spindle cells were infiltrating between the Hürthle cell cords and follicles in a fibrosarcomatous pattern. A battery of immunohistochemical stains was applied to both the thyroid and breast tumors for comparison. Based on the histologic and immunophenotypic features of the fibrosarcomatous components of both the breast and thyroid tumors, we rendered a diagnosis of cystosarcoma phyllodes metastatic to Hürthle cell adenoma. To the best of our knowledge, this unusual case is a first report of tumor-to-tumor metastasis of a sarcoma to a primary thyroid neoplasm.  相似文献   
6.
BACKGROUND: Asthma is an inflammatory airway disease caused by interaction between susceptibility genes and diverse environmental factors. In Israel, asthma seems to be familial and more severe in patients of Iraqi Jewish descent. On the other hand, asthma is less frequent in individuals with familial Mediterranean fever, an autoinflammatory disease prevalent in the Iraqi Jewish community and linked to mutations in the familial Mediterranean fever gene, designated MEFV. OBJECTIVES: To explore a possible role for mutated MEFV in the reduced susceptibility to asthma and to determine its expression in Israeli subjects of Iraqi origins. METHODS: Using a case-control approach, we studied the presence of the 3 most common MEFV mutations (M694V, V726A, and E148Q) in DNA samples from 75 patients with asthma and 45 asymptomatic first-degree relatives, all of Iraqi Jewish origin. The severity of asthma was evaluated using a published severity score. RESULTS: Eleven patients with asthma and 14 of their relatives carried 1 or 2 mutations in the MEFV gene, a carrier rate significantly lower in patients with asthma than in their first-degree relatives and in ethnically matched healthy individuals (P < .03 and P < .003, respectively). Carriers of MEFV mutations had less severe disease, compared with noncarriers (P < .002). CONCLUSION: These findings suggest that MEFV mutations may have a protective effect in the pathogenesis of asthma.  相似文献   
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Tumor metastases are extremely rare in striated muscles. This is surprising given the fact that this tissue constitutes 60% of body weight. The present study focuses on small molecules produced and secreted by muscle cells which possess anti-cancer activity in vivo. Recently we have shown that a low molecular weight fraction (<1000 Dalton) of skeletal muscle cell conditioned medium (muscle factor-MF), markedly inhibits the proliferation of carcinoma, sarcoma or melanoma cell lines in vitro. The MF exerts a cytostatic effect on tumor cell growth and arrests the cells in the G0/G1 of the cell cycle. However, normal cell proliferation, such as bone marrow and fibroblasts, was stimulated following incubation with MF. In this study, the effect of orally administered MF on melanoma and sarcoma growth was examined in mice. The administration of MF to mice inoculated intravenously with melanoma (B16–F10) or sarcoma (MCA-105) cells, resulted in a statistically significant inhibition of metastatic lung foci. In a different model, melanoma was induced in the foot pad and after development of a local lesion, the leg was amputated. A prolonged survival time was observed in the MF treated groups. Since the MF stimulated bone marrow cell proliferation in vitro, we decided to test its efficacy as an inhibitor of the myelotoxic effect exerted by chemotherapy, in vivo. MF, administered after chemotherapy, restored the number of white blood cells and yielded an increased percentage of neutrophils compared with the decline in these parameters after administration of chemotherapy alone. Thus, it is indicated that MF exerted a systemic anti tumor and chemoprotective effect when given orally. It can be concluded that it is bioavailable and is not biodegradable in the digestive system. MF may be considered as a potential therapy for the prevention of tumor spread. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
9.
Developing thymocytes are selected for recognition of molecules encoded by the major histocompatibility complex, purged of self-reactive cells and committed to either the CD4 or CD8 lineage. The 1% of thymocytes that complete these tasks emigrate and join the population of peripheral lymphocytes. Whether T cell maturation is complete at the time of thymic exit has been a subject of debate. Using mice transgenic for green fluorescent protein driven by the recombination activating gene 2 promoter to identify recent thymic emigrants, we now show that T cell differentiation continues post-thymically, with progressive maturation of both surface phenotype and immune function. In addition, the relative contribution of CD4 and CD8 recent thymic emigrants was modulated as they entered the peripheral T cell pool. Thus, T cell maturation and subset contribution are both finalized in the lymphoid periphery.  相似文献   
10.
Amyloid fat pad aspiration specimens for cases with a clinical suspicion of amyloid typically are stained with Congo red and examined by brightfield microscopy. Congophilia with apple-green birefringence by polarization microscopy (PM) is considered diagnostic for amyloid. Examination of Congo red-stained slides by fluorescent microscopy (FM) is considered by some to be a more sensitive detection method. In this study, we assessed the utility of this technique in cytopathology archival slides from abdominal fat pad aspirations previously stained with Congo red dye. Seventy-eight cases of abdominal fat pad aspirations collected during the last 5 yr and stained with the Congo red procedure were obtained from archival files. Additionally, 20 adipose tissue material slides prepared from the surgical pathology specimens were examined as controls. One representative smear was examined in each case using FM equipped with rhodamine excitation/absorption (540/570 nm) filters. Relevant clinical information was obtained in all cases. Twelve cases (15.4%) of the 78 fat pad aspiration cases were reported originally as positive by Congo red stain using polarization and apple-green birefringence as diagnostic criteria. On review, four cases were deemed unsatisfactory. By FM examination 29 of the 74 (39.2%) cases were reclassified as positive for amyloid. The results were confirmed by immunohistochemical stain for amyloid P protein and electron microscopy. A number of similar distinct fluorescence and immunohistochemical patterns were recognized in the positive cases. Minimally weak fluorescence in the adipose tissue was observed in the control cases. The use of FM in Congo red-stained fat pad smears can improve the detection of amyloid in cytology preparations.  相似文献   
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