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991.
The aim of this study was to elucidate whether a novel mitochondrial antioxidant protein, SP-22, is localized in placenta and whether its expression is induced in placenta of lipopolysaccharide (LPS)-exposed mouse. Western blot analysis of normal human placenta indicated that the SP-22 protein was located in the mitochondrial fraction. Immunohistochemical analysis of SP-22 in normal placenta showed that immunoreactive SP-22 was distributed mostly in cytotrophoblastic cells but with almost no signal in syncytiotrophoblasts. The positive signals were also detected in the decidual cells and stromal cells in stem villi of normal placenta. We also examined LPS-mediated inflammatory placenta on day 13 of pregnancy at various time points after LPS injection (50 microg/kg, intraperitoneally). Western blot analysis indicated that LPS approximately quadrupled the expression of SP-22 in placenta of LPS-exposed mouse. When the SP-22 protein was localized immunohistochemically, the decidua and the diploid trophoblasts in the basal zone were intensively stained in placenta of LPS-exposed mouse compared to the control. The localization and inducible expression of SP-22 protein in placenta suggest a possible role in antioxidant system in mitochondria of normal and inflammatory placentae. 相似文献
992.
复合枸杞多糖对接触氟化物者免疫调节和抗脂质过氧化作用 总被引:4,自引:0,他引:4
目的研究复合枸杞多糖对接触氟化物人群免疫调节和脂质过氧化的影响。方法以某有色金属冶炼厂接触NaF的28名工人为观察对象,检测服用复方枸杞多糖胶囊前后其血浆中超氧化物歧化酶(SOD)、丙二醛(MDA)、过氧化氢酶(CAT)的活力和血清免疫球蛋白IgG、IgA、IgM的含量。结果与服用前比较,服用1周后,SOD、CAT活力有显著性升高(P〈0.01),MDA的含量明显下降(P〈0.01),IgG、IgA、IgM的含量均明显增加(P〈0.01)。结论复合枸杞多糖对接触氟化物者可提高其免疫功能和抗脂质过氧化的作用。 相似文献
993.
维生素D3对大鼠卵巢切碎组织性激素分泌影响 总被引:1,自引:0,他引:1
目的研究维生素D3(VD3)在动情周期不同阶段对大鼠卵巢切碎组织分泌雌二醇(E2),孕酮(P4)的影响。方法采用正交表L16(4^5)设计实验,研究VD3(10^-4,10^-7,10^-10mol/L在动情周期的4个阶段(动情前期、动情期、动情后期、动情间期)对卵巢切碎组织分泌E2和P4的影响。结果VD3可影响卵巢切碎组织体外分泌E2(P〈0.001),但不会影响分泌P4(P〉0.05),卵巢切碎组织体外分泌E2和P4与所处的动情周期有关(P〈0.001,P〈0.05)。结论VD3对卵巢类固醇激素生成和分泌有直接影响。 相似文献
994.
Jill R Stewart Rebecca J Gast Roger S Fujioka Helena M Solo-Gabriele J Scott Meschke Linda A Amaral-Zettler Erika del Castillo Martin F Polz Tracy K Collier Mark S Strom Christopher D Sinigalliano Peter DR Moeller A Fredrick Holland 《Environmental health : a global access science source》2008,7(Z2):S3
Innovative research relating oceans and human health is advancing our understanding of disease-causing organisms in coastal ecosystems. Novel techniques are elucidating the loading, transport and fate of pathogens in coastal ecosystems, and identifying sources of contamination. This research is facilitating improved risk assessments for seafood consumers and those who use the oceans for recreation. A number of challenges still remain and define future directions of research and public policy. Sample processing and molecular detection techniques need to be advanced to allow rapid and specific identification of microbes of public health concern from complex environmental samples. Water quality standards need to be updated to more accurately reflect health risks and to provide managers with improved tools for decision-making. Greater discrimination of virulent versus harmless microbes is needed to identify environmental reservoirs of pathogens and factors leading to human infections. Investigations must include examination of microbial community dynamics that may be important from a human health perspective. Further research is needed to evaluate the ecology of non-enteric water-transmitted diseases. Sentinels should also be established and monitored, providing early warning of dangers to ecosystem health. Taken together, this effort will provide more reliable information about public health risks associated with beaches and seafood consumption, and how human activities can affect their exposure to disease-causing organisms from the oceans. 相似文献
995.
Y.-F. Wang S.-L. Wang F.-A. Chen H.A. Chao T.-C. Tsou C.-G. Shy O. Ppke Y.-M. Kuo H.-R. Chao 《Food and chemical toxicology》2008,46(6):1925-1932
The aim of this study was to examine levels of PBDEs in breast milk associated with seafood consumptions of Taiwanese mothers. Our participants were selected from healthy women recruited between December 2000 and November 2001 from a medical center in central Taiwan. The congeners of PBDEs in 20 milk samples were analyzed by a gas chromatograph with a high resolution mass detector. The mean level of BDE47 in breast milk from mothers with pre-pregnant BMI <22.0 kg/m2 had a significantly higher magnitude compared to those with pre-pregnant BMI 22.0 kg/m2 (1.59 vs. 0.995 ng/g lipid, p = 0.041). We did not find significant correlations between PBDEs exposure levels and women’s age, parity, blood pressure, annual household income, and education level. Women who ate more fish and meat did not show significantly higher PBDE levels than those who ate less, but a significant difference in PBDE levels was demonstrated between the higher (2.15 ng/g lipid) and lower (3.98 ng/g lipid) shellfish consuming subjects (p = 0.002) after an adjustment for the confounders. The ratios of PCB153/BDE47, PCB153/BDE153, and PCB153/PBDEs were significantly correlated with frequent consumption of fish and shellfish. The PCB153/BDE153 ratio was not associated with the other dietary habits (i.e. meat). The ratios of PCB153/PBDEs may therefore be a new indicator for exposure as a result of seafood consumption. 相似文献
996.
So T Takenoyama M Sugaya M Yasuda M Eifuku R Yoshimatsu T Hanagiri T Oyama T Kodate M Osaki T Yasumoto K 《Japanese journal of clinical oncology》2001,31(7):311-317
BACKGROUND: Adenosquamous carcinoma of the lung is not a common cancer, but its prognosis is worse than that of adenocarcinoma or squamous cell carcinoma. Therefore, new therapeutic strategies need to be developed to treat this type of lung cancer. Recently, vaccination using tumor antigens which are recognized by cytotoxic T lymphocytes (CTL) has been applied mainly to melanoma patients. We therefore attempted to establish T cell clones specific for autologous tumor cells (AT) from a patient with adenosquamous carcinoma in order to analyze the specific immune responses against AT. METHODS: A lung adenosquamous carcinoma cell line was established from a resected tumor obtained from a 72-year-old patient. Regional lymph node lymphocytes were stimulated weekly with CD80-transfected AT to induce CTL. The CTL activities were assessed by a standard (51)Cr release assay and by cytokine release. RESULTS: We succeeded in inducing an AT-specific CTL line. Using a limiting dilution method, eight T cell clones were established. AT-specific activity was observed in three CD8(+) T cell clones and one CD4(+) T cell clone out of the eight clones tested. Anti-HLA class I and anti-HLA-B/C mAbs inhibited IFN-gamma production from the AT-specific CD8(+) clones co-cultured with AT, thus indicating the restriction element to be HLA-B*5201 or HLA-Cw*1202. In contrast, the CD4(+) T cell clone recognized AT in an HLA class II-restricted manner. CONCLUSIONS: These results are the first demonstration of a successful induction of AT-specific T cell clones from a patient with lung adenosquamous carcinoma. It may therefore supply a possible way to apply specific immunotherapy to this type of lung cancer. 相似文献
997.
Ohnishi A Yamamoto T Izawa K Yamamori S Takahashi K Mega H Jinnai K 《Acta neuropathologica》2000,99(3):327-330
The Ser149Arg mutation of peripheral myelin protein 22 (PMP22) was found in a 19-year-old woman with a sporadic case of Dejerine-Sottas
disease. The patient showed delayed motor development. She walked for the first time with support at the age of 2 years. Scoliosis
developed at age 4 years. Her walking ability was best at age 11. Thereafter, she showed progressive muscle weakness and sensory
disturbances in the distal extremities. At the age of 18 years, the use of a wheelchair became necessary. Motor and sensory
nerve conduction studies showed absent motor and sensory responses on electrical stimulation of the limb nerves. A sural nerve
biopsy specimen showed marked decreases in the numbers of both large and small myelinated fibers, abundant onion-bulb formation,
and hypomyelination. Electron microscopic observation revealed the presence of demyelinated axons and myelin sheaths disproportionately
thin relative to axon diameter. That this was a de novo mutation was established by parentage testing and PMP22 gene analysis
of the parents. The mutation seems to be novel and dominant.
Received: 12 April 1999 / Accepted: 14 June 1999 相似文献
998.
Liss GM Tarlo SM Macfarlane Y Yeung KS 《American journal of respiratory and critical care medicine》2000,162(1):112-118
Occupational asthma (OA) can cause persistent symptoms, but populations with OA have not been followed for the development of serious outcomes such as hospitalization. Subjects receiving compensation for OA during 1980-1993, and a comparison sample of workers with musculoskeletal injuries (INJ) were identified from the Ontario Workers' Compensation Board. We also identified for comparison a group of asthmatic patients (AP) seen at a tertiary care hospital clinic during the same period. The file was matched with the Ontario Ministry of Health data base of hospitalizations through 1996. We compared the frequency of hospitalization of the subgroups with that expected in the general population using standardized morbidity ratios (SMRs), and directly by proportional hazards regression. The study group included 844 OA claimants, 1,556 INJ claimants, and 402 AP. Although admissions for all causes combined and respiratory disease among INJ were less than expected in the general population, admissions for all causes combined exceeded that expected among OA and AP. Admissions for respiratory disease were markedly greater than expected among OA (SMR 9.2) and AP (SMR 17) because of even greater excess admissions for asthma (SMRs 45 and 81, respectively). Compared with those with INJ, those with OA were more likely to be hospitalized for all causes combined (adjusted relative risk [RR] 1.4, 95% confidence interval [CI] 1.2 to 16); cardiovascular disease (RR 1.4, 95% CI 0.9 to 2.0); respiratory disease (RR 5.4, 95% CI 3.8 to 7.7); and asthma (RR 28.1, 95% CI 10.2 to 77.2) but not for malignancies (RR 1.0) or injuries (RR 0.9). Those with OA were admitted to hospital about half as frequently as AP for respiratory disease and asthma (although this was modified by smoking status and sex), but were 30% more likely to be admitted for ischemic heart disease (IHD). Among the OA claimants, factors that were significantly associated with hospitalization for asthma included older age and exposure to agents other than isocyanates. Those with OA became less likely to be hospitalized for asthma with increasing time after onset, particularly after 5 or more years. We conclude that subjects with OA suffer higher rates of hospitalizations for all causes combined, respiratory disease, and asthma than other workers, although less than among AP seen at a tertiary care center. 相似文献
999.
Background
The question of the protective effect of breastfeeding on development of asthma has raised substantial interest, but the scientific evidence of the optimal duration of breastfeeding is controversial. 相似文献1000.
The purpose of this study was to examine whether repetitive muscle tasks in low weight load might influence the fatigue of forearm muscles,and to identify ergonomic risk factors of forearm muscle fatigue in these tasks.Sixteen healthy male volunteers performed eight wrist extensions in different frequency,weight and angle loads while being instructed to keep a dominant upper limb posture as constant as possible.Surface electromyograph(sEMG) was recorded from right extensors digitorium(ED),flexor carpi radialis(FCR),flexor carpi ulnaris(FCU) and extensor carpi ulnaris(ECU) during the task performance.Our results showed that mean power frequency(MPF) and me-dian frequency(MF) values of ED,FCR and FCU were significantly lower(P<0.05) at high fre-quency load level than at low load level.However,MPF and MF values of ED were significantly lower(P<0.01) in higher load groups of frequency,angle and weight than in lower load groups.These results indicated that the fatigue of muscles varied in the same task,and the number-one risk factor of ECU,ED and FCR was angle load. 相似文献