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51.
It has been previously shown that the eel corpuscles of Stannius (CS) synthesize and secrete a substance (PCS) which is functionally and immunologically related to the mammalian parathyrin family. Purification of PCS, including anion-exchange chromatography, ODS C-18 reverse-phase HPLC, and affinity chromatography, showed that a biologically active peak, eluted in 32% acetonitrile, contains a 32- to 34-kDa protein which is 600-fold more potent than the crude extract is a test involving the hypocalcemic response in the CS-deprived eel. Specific immunoprecipitation of protein encoded by mRNA extracted from eel CS indicates that a 45-kDa precursor is involved in PCS synthesis. The hypothetical significance of a "large" parathyrin-like molecule in fish is suggested in relation to what is known about mammalian parathyrin gene expression. 相似文献
52.
53.
Systematic changes in gene expression in postmortem human brains associated with tissue pH and terminal medical conditions 总被引:8,自引:0,他引:8
54.
Plana M Garcia F Oxenius A Ortiz GM Lopez A Cruceta A Mestre G Fumero E Fagard C Sambeat MA Segura F Miró JM Arnedo M Lopalcos L Pumarola T Hirschel B Phillips RE Nixon DF Gallart T Gatell JM 《Journal of acquired immune deficiency syndromes (1999)》2004,36(3):791-799
OBJECTIVES: To analyze the dynamics of both HIV-1-specific CD4 and CD8 T-cell responses during structured treatment interruptions (STIs) in chronically HIV-1-infected (CHI) patients and to correlate them with the viral set point achieved. METHODS: Forty-five early-stage CHI patients who were on highly active antiretroviral therapy (HAART) for at least 1 year and underwent STI were included. Plasma viral load (VL), peripheral blood mononuclear cell (PBMC) lymphoproliferative (LPR) response to HIV p24 protein, and HIV-1 epitope-specific interferon-gammarelease from CD8 T cells were measured over a minimum study period of 2 years. RESULTS: VL set point during final STI was both significantly lower than, and positively correlated to, baseline VL (P < 0.0001: mean VL reduction 0.77 log10, and r = 0.42, P = 0.004, respectively). CD4 LPRs to p24 increased significantly (P = 0.001) between day 0 of the first STI cycle and 4th STI but decreased thereafter. VL set point during final STI was significantly and negatively correlated with LPRs to p24 at both 2nd STI and 4th STI. Nevertheless, at week 52, 12 weeks after the end of the last STI, LPRs were weak and transient in all patients and were not correlated with VL set point. Moreover, the magnitude and breadth of HIV-1-specific CD8 T-cell responses increased significantly (P < 0.0001) between day 0 and week 52. The largest increases occurred during the final STI. Even though VL reached set point by week 12 of the final STI, HIV-1-specific CD8 T-cell responses did not stabilize but rather increased until the end of the follow-up and did not correlate with plasma VL (r = 0.01, P = 0.88). CONCLUSIONS: STIs do not lead to control of viral replication in CHI patients, probably due to the fact that boosted CTL responses lack strong and durable helper T-cell responses. To reset the VL set point, new approaches that effectively augment and preserve helper T-cell responses should be investigated. 相似文献
55.
Humphrey RK Beattie GM Lopez AD Bucay N King CC Firpo MT Rose-John S Hayek A 《Stem cells (Dayton, Ohio)》2004,22(4):522-530
56.
Epidemiology of Cyclospora cayetanensis and other intestinal parasites in a community in Haiti
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Lopez AS Bendik JM Alliance JY Roberts JM da Silva AJ Moura IN Arrowood MJ Eberhard ML Herwaldt BL 《Journal of clinical microbiology》2003,41(5):2047-2054
We conducted an exploratory investigation in a community in Haiti to determine the prevalence of Cyclospora cayetanensis infection and to identify potential risk factors for C. cayetanensis infection. In 2001, two cross-sectional stool surveys and a nested case-control study were conducted. In 2002, a follow-up cross-sectional stool survey was conducted among children < or =10 years of age. Stool specimens from study participants and water samples from their wells were examined for Cyclospora and other intestinal parasites. In stools, the prevalence of infection with Cyclospora in persons of all ages decreased from 12% (20 of 167 persons) in February 2001 to 1.1% (4 of 352 persons) in April 2001, a 90.8% decrease. For children < or =10 years of age, the prevalence rates were 22.5% (16 of 71 children) in February 2001, 3.0% (4 of 135 children) in April 2001, and 2.5% (2 of 81 children) in January 2002. Use of the water from the artesian well in the northern region of the community versus the one in the south was the only risk factor associated with Cyclospora infection in multivariate analyses (odds ratio, 18.5; 95% confidence interval, 2.4 to 143.1). The water sample from one of the nine wells or water sources tested (one sample per source) in January 2001, shortly before the investigation began, was positive for Cyclospora by UV fluorescence microscopy and PCR. None of the water samples from the 46 wells or water sources tested during the investigation (one sample per source per testing period, including the artesian wells) were positive for Cyclospora. Further studies are needed to assess the role of water as a possible risk factor for Cyclospora infection in Haiti and other developing countries. 相似文献
57.
Inhibitory monoclonal antibody against a (myristylated) small-molecular-weight antigen from Plasmodium falciparum associated with the parasitophorous vacuole membrane. 总被引:3,自引:1,他引:3
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U A Kara D J Stenzel L T Ingram G R Bushell J A Lopez C Kidson 《Infection and immunity》1988,56(4):903-909
A small-molecular-weight antigen that occurs in asexual blood stages in synchronized cultures of Plasmodium falciparum was detected by a monoclonal antibody which inhibits parasite growth in vitro. This antigen, QF116, showed a molecular weight of 15,000 in parasite strain FCR-3K+ from The Gambia and 19,000 in strain FCQ-27 from Papua New Guinea. The protein did not show significant glycosylation by galactose or glucosamine labeling but was found to be acylated by myristic acid. By using immunogold labeling and electron microscopy, the location of the antigen could be attributed to the parasitophorous vacuole membrane and to inclusions and vesicles residing within the cytoplasm of the erythrocyte host cell. 相似文献
58.
Rheumatic heart disease: proinflammatory cytokines play a role in the progression and maintenance of valvular lesions 总被引:3,自引:0,他引:3
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Guilherme L Cury P Demarchi LM Coelho V Abel L Lopez AP Oshiro SE Aliotti S Cunha-Neto E Pomerantzeff PM Tanaka AC Kalil J 《The American journal of pathology》2004,165(5):1583-1591
Heart lesions of rheumatic heart disease (RHD) patients contain T-cell clones that recognize heart proteins and streptococcal M peptides. To functionally characterize heart-infiltrating T lymphocytes, we evaluated their cytokine profile, both directly in situ and in T-cell lines derived from the heart (HIL). Interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, interleukin (IL)-4, and IL-10 expressions were characterized in 20 heart tissue infiltrates from 14 RHD patients by immunohistochemistry. IFN-gamma-, TNF-alpha-, and IL-10-positive cells were consistently predominant, whereas IL-4 was scarce in the valves. In agreement with these data, the in vitro experiments, in which 13 HILs derived from heart samples of eight patients were stimulated with M5 protein and the immunodominant M5 (81-96) peptide, IL-4 was detected in HIL derived from the atrium (three of six) but not from the valve (zero of seven). IFN-gamma and IL-10 production were detected in culture supernatants in 11 of 13 and 6 of 12 HILs, respectively. The predominant IFN-gamma and TNF-alpha expression in the heart suggests that Th1-type cytokines could mediate RHD. Unlike in reversible myocardium inflammation, the significantly lower IL-4 expression in the valvular tissue (P = 0.02) may contribute to the progression of the RHD leading to permanent valvular damage (relative risk, 4.3; odds ratio, 15.8). The lack of IL-4 in vitro production by valve-derived HIL also emphasizes the more severe tissue destruction in valves observed in RHD. 相似文献
59.
A malformed child with a recombinant chromosome 7, rec(7) dup p, derived from a maternal pericentric inversion inv(7)(p15q36).
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![点击此处可从《Journal of medical genetics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A Delicado E Escribano I Lopez Pajares A Diaz de Bustamante S Carrasco 《Journal of medical genetics》1991,28(2):126-127
We report a child with facial dysmorphic features, hypoplasia of the external genitalia, intestinal malrotation, congenital cardiac defect, and minor limb anomalies. Chromosome studies showed a recombinant chromosome 7, rec(7) dup p, resulting from a maternal pericentric inversion inv(7)(p15 q36). Thus, this child had partial trisomy 7p in addition to a small distal monosomy 7. The clinical findings are compared with those found in previous reports of trisomy 7p. Finally, some general principles for genetic counselling are discussed. 相似文献
60.
Reza-Albarran AA Gomez-Perez FJ Lopez JC Herrera M Gamboa-Dominguez A Keirns C Aranda A Rull JA 《Endocrine pathology》1999,10(3):251-257
Pigmented nodular cortical hyperplasia, a rare cause of Cushing’s syndrome, is characterized by resistance to inhibition with
dexamethasone and normal sized adrenal glands with multiple, small pigmented nodules. The disorder may be a component of a
syndrome inherited as an autosomal dominant pattern that includes intra- and extracardiac myxomas, lentiginous lesions, blue
nevi, other functional endocrine tumors, and peripheral nerve tumors (Carney’s complex).
We report a patient in whom bilateral myelolipomas were found, in addition to the usual features of this complex. A 29-yr-old
man was admitted to the hospital for Cushing’s syndrome of probably more than 15 yr duration. Physical examination showed
diffuse facial hyperchromatic macules, 0.2–0.5 cm, predominantly around the lips and on the palmar surfaces of the fingers.
Results with dexamethasone suppression nocturnal testing (1 and 8 mg) were compatible with an adrenal adenoma. The computed
tomography (CT) of the sella turcica was normal. Adrenal CT showed a tumor in the left gland with a double component: one
solid and another suggestive of fat, consistent with an angiomyelolipoma. Following 5 wk treatment with ketoconazole, 800
mg per day po, serum cortisol decreased to 5.9 μg/dL, morning and evening, respectively.
Bilateral adrenalectomy was performed. Pathologic examination revealed pigmented nodular cortical hypersplasia and a dominant
myelolipoma in the left adrenal. A microscopic myelolipoma was identified in the right adrenal.
An echocardiogram showed a mass on the posterior wall of the left ventricle which was a myxoma. Study of the patient's family
disclosed two sisters with facial lentigines. Echocardiograms were performed on all available first degree relatives: all
were normal. Nocturnal inhibition with dexamethasone revealed that one of the patient’s sisters with lentigines also had hypercortisolism.
Myelolipoma has been reported in association to Cushing syndrome in humans and experimentally after pituitary extracts in
animals. The relationship between this finding and the Carney’s complex remain elusive. 相似文献