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101.
OBJECTIVE: To evaluate the expression of HSP70 and pS2 and to determine whether it may be an additional prognostic variable in the prediction of recurrence and survival in rectal adenocarcinomas. METHODS: The paraffin sections of 45 patients with rectal carcinoma who were treated with surgical resection were stained with HSP70 and pS2 antibodies by using the standard biotin immunoperoxidase method. Cytoplasmic staining for both antibodies was scored semiquantitatively. RESULTS: Only 16 (35.6%) tumors showed a positive cytoplasmic reaction with HSP70 antibody, while pS2 expression was observed in 26 (57.8%) tumors. There was an association between HSP70 and pS2 expression (P=0.002). No correlations were found between HSP70 and pS2 expression and tumor recurrence or overall survival and other prognostic factors. However, the type of surgical resection was significantly associated with pS2 expression status (P=0.013). Significant correlations were detected between tumor recurrence and other clinicopathologic parameters, such as clinical stage, lymph node involvement, and resection type (P=0.015, P=0.015, and P=0.03, respectively). Resection type was significantly associated with clinical outcome, recurrence, and metastasis (P=0.009, P=0.03, P<0.01, respectively). In addition, there was a statistically significant relationship between clinical stage and final outcome (P=0.005). CONCLUSIONS: The strong correlation between pS2 expression and incomplete surgical resection suggests that pS2 may be related to invasive tumor behavior and may also play a role in tumor recurrence, although this latter association did not reach statistical significance in this study. HSP70 expression does not appear to be related to tumor invasiveness or tumor recurrence.  相似文献   
102.
Using a spectrophotometric NBT reduction assay and phagocytosis, we identified that production of superoxide anions and phagocytic activity of hemocytes from Macrobrachium rosenbergii were significantly higher in the presence of rat, rabbit, and chicken erythrocytes than with human, pig, or horse erythrocytes. Hemocytes stimulated with MrL, MrLMab, or PMA increased 4.7, 5.1, and 6.1 fold, respectively, the oxidative response as compared to non-stimulated hemocytes. MrLMab together with MrL increased 5.7 fold the oxidative capacity of hemocytes as compared to non-stimulated cells. These effects were inhibited with 100 mM GalNAc, GlcNAc, or Neu5Ac and 0.2 microM of sialylated submaxillary gland mucin and fetuin. Piroxicam inhibited (P < 0.05) the production of O(2)(-) induced by MrL, whereas iodoacetamide inhibited the effect of MrLMAb (P < 0.05) in a dose-dependent manner. Our results suggest that MrLMab might activate the oxidative burst through the metabolism of glucose as opposed to MrL which utilizes NADPH-independent mechanisms, very probably through pro-inflammatory metabolites.  相似文献   
103.
Infant guinea-pigs born to mothers immunized against influenza virus by infection during pregnancy were reared from birth by non-immune foster mothers. As a control for the effects of fostering, a similar group were fostered to immune mothers. Fostering, regardless of the immune state of the foster-mother, increased the susceptibility of the infant to upper respiratory tract infection. Increased susceptibility was associated with ablation of the infants IgM and IgA antibody responses and reduced secretion of transplacentally acquired IgG antibody in nasal secretions. In the reciprocal experiment, infants of non-immune mothers fostered to immune mothers cleared virus more rapidly than their peers who were fed by their own mothers. This protective effect was associated with an enhanced nasal IgM and IgA antibody response. Infants of immune mothers separated from their mothers at birth and hand-reared on a cow's-milk-based formula feed suffered an increased susceptibility to the virus similar to that seen in fostered infants. Addition of a pool of expressed milk from a group of immune mothers, including their own, to the feed of hand-reared infants did not reduce their susceptibility. However, a further group of infants fed a non-cellular whey fraction of the same milk pool secreted significantly lower titres of virus. This increased protection was associated with elevated levels of IgG antibody secretion into nasal washes early in infection.  相似文献   
104.
105.
Invasion into surrounding brain tissue is a fundamental feature of gliomas and the major reason for treatment failure. The process of brain invasion in gliomas is not well understood. Differences in gene expression and/or gene products between invading and noninvading glioma cells may identify potential targets for new therapies. To look for genes associated with glioma invasion, we first employed Affymetrix microarray Genechip technology to identify genes differentially expressed in migrating glioma cells in vitro and in invading glioma cells in vivo using laser capture microdissection. We observed upregulation of a variety of genes, previously reported to be linked to glioma cell migration and invasion. Remarkably, major histocompatiblity complex (MHC) class I and II genes were significantly downregulated in migrating cells in vitro and in invading cells in vivo. Decreased MHC expression was confirmed in migrating glioma cells in vitro using RT-PCR and in invading glioma cells in vivo by immunohistochemical staining of human and murine glioblastomas for beta2 microglobulin, a marker of MHC class I protein expression. To the best of our knowledge, this report is the first to describe the downregulation of MHC class I and II antigens in migrating and invading glioma cells, in vitro and in vivo, respectively. These results suggest that the very process of tumor invasion is associated with decreased expression of MHC antigens allowing glioma cells to invade the surrounding brain in a 'stealth'-like manner.  相似文献   
106.
Mesothelial/monocytic incidental cardiac excrescence (MICE) is a very uncommon lesion. Diagnosis is incidental and may simulate thrombotic lesions. One of the hypotheses with regard to the etiology of this lesion is a previous cardiac procedure especially mitral valve repair or commissurotomy. Herein, we describe a MICE incidentally found in a patient who underwent mitral valve replacement, as a thrombotic lesion on the left atrial auricle. Histopathologic examination suggested MICE lesions and immunohistochemical stains confirmed it.  相似文献   
107.

Background

Several investigations have studied gait variability of individuals with anterior cruciate ligament (ACL) deficiency; however, the effect of dual-tasking on the gait variability of these individuals remained unclear. The aim of the present study was to determine the effect of gait speed and dual-tasking on knee flexion–extension variability in subjects with and without ACL deficiency.

Methods

The knee flexion–extension Lyapunov exponent (LyE) was measured in 22 ACL-deficient (Mean±SD) (25.95?±?4.69?years) and 22 healthy subjects (24.18?±?3.32?years). They walked at three levels of gait speed in isolation or concurrently with a cognitive task.

Results

Repeated-measure analyses of variance (ANOVAs) demonstrated that the interaction of group by gait speed was statistically significant. As the gait speed increased from low to high, the knee flexion–extension LyE significantly decreased for the subjects with ACL deficiency (effect size: 0.57, P?=?0.01). The interaction of group by cognitive load was not statistically significant (P?=?0.07). In addition, the ACL-deficient subjects had statistically slower reaction times than healthy subjects during the dual-task compared with the single-task condition.

Conclusions

The ACL-deficient and healthy individuals had a tendency to maintain safe gait. It seems that the ACL-deficient subjects sacrificed the cognitive task more than the healthy individuals to pay more attention toward gait. Additionally, it seems that the gait speed was more challenging than cognitive load on the stride-to-stride variability in the individuals with ACL deficiency.  相似文献   
108.
The problem of morphine tolerance and dependence is a universal phenomenon threatening social health everywhere the world. The major objective of this paper was to investigate the effects of fruit essential oil (FEO) of Cuminum cyminum on acquisition and expression of morphine tolerance and dependence in mice. Animals were rendered dependent on morphine using the well-established method in which was morphine (50, 50, 75 mg/kg; s.c.) injected three times daily for 3 days. In experimental groups, administration of FEO (0.001, 0.01, 0.1, 0.5, 1 and 2%; 5 ml/kg; i.p.) or Tween-80 (5 ml/kg; i.p.) was performed 60 min prior to each morphine injection (for acquisition) or the last injection of morphine on test day (for expression). Morphine tolerance was measured by tail-flick before and after administration of a single dose of morphine (50 mg/kg; s.c.) in test day (4th day). Morphine dependence was also evaluated by counting the number of jumps after injection of naloxone (5 mg/kg; i.p.) on the test day. The results showed that Cumin FEO, only at the dose of 2%, significantly attenuated the development of morphine tolerance (P < 0.01) and dependence (P < 0.05) while it could be significantly effective on expression of morphine tolerance (1 and 2%) and dependence (0.5, 1 and 2%) in a dose-dependent manner. Solely Cumin FEO injection (0.001–2%) did not show any analgesic effect. In conclusion, the essential oil of Cuminum cyminum seems to ameliorate the morphine tolerance and dependence in mice.  相似文献   
109.
Mayotte is a little French island, located in the Indian ocean, between Madagascar and Mozambic. Officially, the population goes up to 150,000 inhabitants, but in fact, it probably comes up to about 200,000 people, because of a very numerous illegal immigration, especially coming from Anjouan, the nearest Comorian island. Up to now there are no data about HIV in Mayotte. There is only one adult medical unit (except intensive care). All patients detected as seropositive for HIV are sent for treatment in this unit. The only case of systematically proposed HIV serology is pregnancy, and this since 1994. 70% to 80% of women accept it. There are annually 6000 deliveries in Mayotte. When a seropositivity is detected, screening is systematically proposed to other members of the family. Epidemiology does not seem to worsen, even if detection is increasing: 8675 tests done in 1998, 9142 in 1999, 12,085 in 2000. All cases of seropositivity attended to at present time in our unit have been registered and studied, apart from patients who died before this study, and those who did not consult for more than two years. There were 8 HIV positive people who died since 1990 in Mayotte, most of them in 1991, 1992. There was no death in the last years, nor sanitary evacuation, except one. 50 people are registered: 20 males, 30 females. Average age is 34. 39 Comorian people, 10 metropolitans, and one from another origin. Contamination was heterosexual in 43 cases, intravenous drug user in 1 case, homosexual in 2 cases, professional in 1 case, unknown in 3 cases. There are 4 double contamination Ag Hbs/HIV, and 2 HCV/HIV. 39 subjects are at A stage, 5 B, 6 C. The beginning of the epidemic in Mayotte took place probably around 1990, among militaries and prostitutes. Now, transmission keeps going on, in most cases, heterosexual, as it occurs in the nearby Africa. Polygamy, official or officious, has a leading role. Females who were detected during pregnancy have obtained zidovudine, or have been able to pursue previous therapy. Medical care and therapy are free in Mayotte, but sometimes there are delays in supplying medicines or in returning results. Epidemic has not increased up to now; even though screening has. There are very few pediatric cases: only 4 cases were notified in Mayotte until now: one who died very soon, one who has gone to live in Reunion island, and two who are still in Mayotte: one is 12 years old, and another one 5 years old.  相似文献   
110.
Isolation rearing has long been suspected to alter hormonal and behavioral responses to stress. Two experiments were conducted to test the hypothesis that isolates are more timid or fearful than socially reared rats when exposed to novel test environments. In both, isolate response to 3 graded stressors was compared to that of socially-reared rats. In the first experiment, animals were handled, shocked or not treated prior to testing to produce three levels of conditioned fear. They were then tested on four paradigms previously shown sensitive to conditioned fear: open field activity, emergence latency, auditory startle, and latency to accept food from the experimenter. In the second experiment, rats were given a 0-, 5- or 20-min forced swim, then sacrificed for analysis of plasma corticosterone and pituitary and hypothalamic beta-endorphin. It was found that isolates showed little evidence of enhanced behavioral timidity, although rearing effects were seen on all 4 behavioral measures. Plasma corticosterone levels increased in a graded fashion over the course of the forced swim, but there was no effect of rearing conditions. While there were no effects of rearing or stress on hypothalamic beta-endorphin, pituitary beta-endorphin content was lower in females than in males, and isolate males had lower pituitary endorphin than social males. In summary, these experiments provide no evidence that isolation rearing produces a primary, global increase in fearfulness, but identify several behavioral and hormonal differences associated with differential housing in rats.  相似文献   
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