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51.
BACKGROUND: The purpose of this study was to determine if evidence of functional heterogeneity between subtypes of the Kupffer cell (KC) may be involved in the mechanism of the protective effect of gadolinium chloride (GdCl3) in endotoxemia. METHODS: Rats pretreated with or without GdCl3 were administered lipopolysaccharide (LPS) or vehicle. Serum and liver tissues were collected after LPS administration for cytokine measurements and pathological and immunohistochemical evaluation. RESULTS: After LPS administration, increases in expression of TNF-alpha and IL-6 mRNA in the liver were blunted significantly by GdCl3. In control liver tissue, ED2-positive cells were a predominant fraction, with a few ED1-positive cells, and GdCl3 eliminated only ED2-positive cells. Further, ED2-positive cells were larger in size than ED1-positive ones. Importantly, the number of ED1-positive cells in the liver was increased about threefold in the control group but not in the GdCl3 group after LPS injection. Intermediate or large KCs isolated by counterflow centrifugal elutriation showed greater capacity for phagocytosis and production of superoxide and TNF-alpha than small ones. In contrast, IL-6 production was increased to a greater extent in small than in intermediate or large cells. GdCl3 eliminated the intermediate or large KC subpopulation predominantly. CONCLUSION: Collectively, functional heterogeneity of the KC population was involved in the mechanism of the protective effects of GdCl3 in endotoxemia. TNF-alpha derived from activated intermediate or large KCs may activate small KCs and the latter may be recruited to other organs, such as lungs and kidneys, and produce a large amount of IL-6, leading to multiple organ failure.  相似文献   
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We conducted surveys to investigate the nature of the recovery processes and psychological reactions of children and adolescents affected by the Great Hanshin Awaji Earthquake. The investigations were carried out 4 times at 4 months, 6 months, one year and two years after the disaster. SUBJECTS: About 9000 school children in the 3rd grade, the 5th grade, the 8th grade living in the disaster area. METHOD: The questionnaire consisted of 9-12 items regarding situation and behavior when the earthquake occurred, and 22 items regarding mental health condition, and was filled out in the classroom under supervision by the teacher in charge. The responses were rated from 1 to 4 depending on the frequency of the symptoms, and statistically analyzed. RESULTS: By factor analysis, three factors were elicited. Factor 1 was interpreted as being related to fear and anxiety, factor 2 as related to depression and physical symptoms, and factor 3 as related to pro-social tendencies. These 3 factors were distinct and stable throughout all 4 surveys and each of them showed unique recovery processes. The mean score of factor 1 was highest at 4 months after the earthquake, and decreased as time passed. This factor shows that fear and anxiety seem to be directly related to the experience of the earthquake. According to the severity of the disaster, more severe damage brought about a higher mean score of factor 1. Furthermore, younger children and girls were more strongly affected. Each of the differences in the severity of disaster, in age, and in gender decreased as time passed. The mean score of factor 2 peaked at 6 months, and it slightly recovered after one year. However, the score at the 1st year was still higher than that of the 4th month. At two years the score returned to almost the same level as that of the 4th month. We think that factor 2, involving depressive mood and psychophysical symptoms, may be a secondary phenomenon to fear and anxiety. Other possibilities are that they may be caused by environmental changes after the disaster, inconveniences of daily life, loss of jobs of parents, or masked by hypomanic mood which covered over the disaster area soon after the earthquake (so-called heroic phase). Older children have a greater tolerance for depressive mood and psychophysical symptoms, but those symptoms occurring in older children have a tendency to continue for a longer time. Girls are more heavily affected and need more time to recover from trauma than boys. The mean score of factor 3 showed a gradual decrease as time passed. There was no difference in the way of decrease according to the severity of disaster, age and gender. It may be natural that, since the interest in the earthquake decreased as time passed, consideration for the victims decreased. CONCLUSIONS: The problems of mental health of children and adolescents after the disaster may consist of at least 2 different components; "fear and anxiety," which appeared just after the disaster and decreased earlier; "depressive and psychophysical symptoms" appeared later and stayed longer.  相似文献   
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OBJECTIVE: To examine the characteristics of infants suffering from failure to thrive in a community based cohort in Israel and to ascertain the effect of failure to thrive on their cognitive development. METHODS: By review of records maintained at maternal and child health clinics in Jerusalem and the two of Beit Shemesh, epidemiological data were obtained at age 15 months on a cohort of all babies born in 1991. For each case of failure to thrive, a matched control was selected from the same maternal and child health clinic. At age 20 months, cognitive development was measured, and at 25 months a home visit was carried out to assess maternal psychiatric status by questionnaire, and the HOME assessment was performed to assess the home environment. RESULTS: 3.9% of infants were found to have fallen below the third centile in weight for at least three months during the first year of life. Infants with failure to thrive did not differ from the general population in terms of obstetric or neonatal complications, birth order, or parents' ethnic origin, age, or years of education. The infants with failure to thrive did have lower birthweights and marginally smaller head circumferences at birth. Developmental assessment at 20 months of age showed a DQ of 99.7 v 107.2 in the matched controls, with 11.5% having a DQ below 80, as opposed to only 4.6% of the controls. No differences were found in maternal psychiatric problems as measured by a self report questionnaire. There were, however, significant differences in subscales of the HOME scale. CONCLUSIONS: (1) Infants who suffered from failure to thrive had some physiological predispositions that put them at risk; (2) failure to thrive may be an early marker of families providing suboptimal developmental stimulation.  相似文献   
55.
Wound bed preparation: a systematic approach to wound management   总被引:6,自引:0,他引:6  
The healing process in acute wounds has been extensively studied and the knowledge derived from these studies has often been extrapolated to the care of chronic wounds, on the assumption that nonhealing chronic wounds were simply aberrations of the normal tissue repair process. However, this approach is less than satisfactory, as the chronic wound healing process differs in many important respects from that seen in acute wounds. In chronic wounds, the orderly sequence of events seen in acute wounds becomes disrupted or "stuck" at one or more of the different stages of wound healing. For the normal repair process to resume, the barrier to healing must be identified and removed through application of the correct techniques. It is important, therefore, to understand the molecular events that are involved in the wound healing process in order to select the most appropriate intervention. Wound bed preparation is the management of a wound in order to accelerate endogenous healing or to facilitate the effectiveness of other therapeutic measures. Experts in wound management consider that wound bed preparation is an important concept with significant potential as an educational tool in wound management.
This article was developed after a meeting of wound healing experts in June 2002 and is intended to provide an overview of the current status, role, and key elements of wound bed preparation. Readers will be able to examine the following issues;
• the current status of wound bed preparation;
• an analysis of the acute and chronic wound environments;
• how wound healing can take place in these environments;
• the role of wound bed preparation in the clinic;
• the clinical and cellular components of the wound bed preparation concept;
• a detailed analysis of the components of wound bed preparation.
(WOUND REP REG 2003;11:1–28)  相似文献   
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57.
Renal toxicity of non-ionic contrast medium (iohexol) for drip infused pyelography (DIP) was studied in a randomized trial of nine patients with normal renal function. Urine samples were collected before and immediately after DIP, and analyzed for albumin, an index of glomerular permeability; gamma-glutamyl transpeptidase (gamma-GTP), a brush-border enzyme; N-acetyl-beta-glucosaminidase (NAG), a lysosomal enzyme; alpha 1 microglobulin (alpha 1MG) and beta 2 microglobulin (beta 2MG), an index to tubular proteinuria; and creatinine. The urinary excretion of enzymes and proteins was compared with urinary creatinine. Urinary excretion of gamma-GTP and NAG increased significantly (P less than 0.001, 0.02) after DIP. Urinary alpha 1 MG and beta 2-MG did not change significantly. The change of urinary albumin was mild. Our data suggest that non-ionic, low osmolal radiocontrast medium ioheol shows a lower renal tubular toxicity, and the brush-border enzyme gamma-GTP and lysosomal enzyme NAG are considered as a good index for renal tubular damage.  相似文献   
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59.
In innate immunity, activated natural killer (NK) cells attack and damage pathogens such as bacteria and virus without restriction by the MHC antigen. NK cells activated by IL-12 have been reported to recognize and kill tumor cells in perforin-mediated apoptosis. We have reported that D-Fraction, a polysaccharide extracted from the maitake mushroom (Grifola frondosa), activates macrophages, dendritic cells, and T cells and inhibits the growth of tumor cells. However, the effects of D-Fraction on NK cell function in the innate immune response are not well known. In the present study, we administered D-Fraction to MM-46 mammary tumor-bearing C3H/HeJ mice intraperitoneally for 3 consecutive days and investigated its effects on the activation and cytotoxicity of NK cells. D-Fraction significantly enhanced the cytotoxicity against NK-sensitive YAC-1 cells and the expression of CD223 on NK cells. D-Fraction also increased the expression of CD86 on macrophages. In addition, the levels of IL-12 in the culture supernatant of whole spleen cells and in serum increased, compared with the control corresponding to an increase in expression of IL-12 receptor betaI on NK cells. These results suggest that D-Fraction enhances the cytotoxicity of NK cells through the production of IL-12 by macrophages activated by D-Fraction.  相似文献   
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