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BACKGROUND: Although it is known that pentoxifylline (PTX) produces various beneficial effects during sepsis, it remains unknown whether this agent has any salutary effects on the depressed vascular responsiveness to adrenomedullin (ADM), a novel potent vasodilatory peptide, under such conditions. MATERIALS AND METHODS: Adult male Sprague-Dawley rats were subjected to polymicrobial sepsis by cecal ligation and puncture (CLP). One hour after CLP, PTX (50 mg/kg body wt) or vehicle (normal saline) was infused intravenously over 90 min. Twenty hours after CLP (i.e., the late, hypodynamic stage of sepsis), the thoracic aorta and small intestine were isolated and preconstricted by norepinephrine. Rat ADM (10(-7) M) was applied, and the percentage of ADM-induced relaxation in the aortic rings and resistance vessels in the small intestine was determined. In addition, plasma ADM was determined by radioimmunoassay and tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-1beta, and IL-6 levels were measured by enzyme-linked immunosorbent assay. RESULTS: The percentage of ADM-induced vascular relaxation in the aortic rings and resistance vessels of the isolated gut was significantly reduced 20 h after CLP. Administration of PTX early after the onset of sepsis, however, prevented the decrease in vascular ADM responsiveness at the macro- and microcirculatory levels. Plasma ADM levels increased after CLP, irrespective of PTX infusion, indicating that the effect of PTX was not mediated by altering ADM release. The upregulated TNF-alpha, IL-1beta, and IL-6 during late sepsis were, however, attenuated by PTX administration, suggesting that maintenance of ADM responsiveness by this agent appears to be due to downregulation of these cytokines. CONCLUSIONS: Since early administration of PTX maintains vascular ADM responsiveness even during the late stage of sepsis, this agent appears to be a useful adjunct in preventing the deterioration in hemodynamics and cardiovascular function during the progression of polymicrobial sepsis.  相似文献   
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Objective. To quantify the effects of informal caregiver availability and public funding on formal long-term care (LTC) expenditures in developed countries.
Data Source/Study Setting. Secondary data were acquired for 15 Organization for Economic Cooperation and Development (OECD) countries from 1970 to 2000.
Study Design. Secondary data analysis, applying fixed- and random-effects models to time-series cross-sectional data. Outcome variables are inpatient or home heath LTC expenditures. Key explanatory variables are measures of the availability of informal caregivers, generosity in public funding for formal LTC, and the proportion of the elderly population in the total population.
Data Collection/Extraction Method. Aggregated macro data were obtained from OECD Health Data, United Nations Demographic Yearbooks, and U.S. Census Bureau International Data Base.
Principal Findings. Most of the 15 OECD countries experienced growth in LTC expenditures over the study period. The availability of a spouse caregiver, measured by male-to-female ratio among the elderly, is associated with a $28,840 (1995 U.S. dollars) annual reduction in formal LTC expenditure per additional elderly male. Availability of an adult child caregiver, measured by female labor force participation and full-time/part-time status shift, is associated with a reduction of $310 to $3,830 in LTC expenditures. These impacts on LTC expenditure vary across countries and across time within a country.
Conclusions. The availability of an informal caregiver, particularly a spouse caregiver, is among the most important factors explaining variation in LTC expenditure growth. Long-term care policies should take into account behavioral responses: decreased public funding in LTC may lead working women to leave the labor force to provide more informal care.  相似文献   
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As a general rule, surgery, whenever possible followed by irradiation, is considered to be a standard treatment for pyriform sinus cancer. In early primary lesions, many different approaches have been tried for larynx preservation. From 1990-1997, 7 patients with pyriform sinus carcinoma without the involvement of pyriform sinus apex were treated with partial laryngopharyngectomy at the Asan Medical Center. Three patients were T1 stage and four were T2. All patients had nodal metastases and were treated with neck dissection and postoperative radiotherapy. Follow-up period was 1-8 years. One regional recurrence and one distant metastasis occurred; however, there was no recurrence at the primary site. The voices of all the patients were saved. The most uncomfortable postoperative symptom was mild aspiration. From these results, we can conclude that partial laryngopharyngectomy with neck dissection might be the favorable treatment modality for selected cases of pyriform sinus cancer.  相似文献   
46.
Nevus sebaceous (NS) is a common congenital hamartoma of the skin composed predominantly of sebaceous glands. Although most NS are benign skin tumors, malignant transformations have been reported. There is still controversy about the lifetime risk of malignant degeneration and precise surgical criteria. This study reports cases of malignant degeneration and suggests a surgical treatment algorithm. The medical records of patients with basal-cell carcinoma (BCC) arising from NS between January 2001 and January 2021 were retrospectively reviewed. Patient demographics including lesion location, and tumor size were investigated. The symptoms, histological findings before and after excision, complications, and recurrence during 2-year follow-up periods were investigated. Ten patients were identified with BCC arising from NS lesions. All patients were female and the mean age was 52.11 years. All patients complained of sudden morphological changes, the most common type being rapid color changes. Two cases had histological findings that showed a miss-match between punch biopsy and excisional biopsy results. No recurrence was detected 2 years after surgeries in any patients. Cases after third stage, especially in over 40 years who report morphologic changes, should undergo total surgical excision as the first approach, with strong suspicion of malignant degeneration.  相似文献   
47.
Gut microbiota dysbiosis is strongly associated with psychiatric disorders and inflammatory bowel disease (IBD). Herein, we examined whether the fecal microbiota of IBD patients with depression (IBDD) and their gut microbiota culture (iGm) could cause depression and colitis in mice and anti-inflammatory probiotics could mitigate depression in iGm-transplanted or immobilization stress (IS)-exposed mice. Fecal microbiota transplantation (FMT) from IBDD patients, which exhibited Enterobacteriaceae-rich gut microbiota, and its gut microbiota culture (iGm) increased depression-like behaviors in mice. Their treatments heightened the blood lipopolysaccharide (LPS) level and colonic IL-1β and IL-6 expression. However, FMT from healthy volunteers or sulfasalazine treatment alleviated cGm-induced depressive-like behaviors and hippocampal and colonic inflammation in mice. Moreover, oral administration of Lactobacillus plantarum NK151, Bifidobacterium longum NK173, and Bifidobacterium bifidum NK175, which inhibited LPS-induced IL-6 expression in macrophages, alleviated cGm-induced depression-like behaviors, hippocampal NF-κB+Iba1+ cell numbers and IL-1β and IL-6 expression, blood LPS, IL-6, and creatinine levels, and colonic NF-κB+CD11c+ number and IL-1β and IL-6 expression in mice. Treatment with NK151, NK173, or NK175 mitigated immobilization stress (IS)-induced depressive-like behaviors, neuroinflammation, and gut inflammation in mice. NK151, NK173, or NK175 also decreased IS-induced blood LPS, IL-6, and creatinine levels. The transplantation of Enterobacteriaceae-rich gut microbiota can cause depression and colitis, as IS exposure, and anti-inflammatory NK151, NK173, and NK175, may alleviate stress-induced fatigue, depression, and colitis by regulating the expression of proinflammatory and anti-inflammatory cytokines through the suppression of gut bacterial LPS.  相似文献   
48.
目的:测定市场上实际流通的商品胡桐泪药材中多糖的含量并对其单糖组成进行分析,以多糖为指标评价药材质量。方法:采用苯酚-硫酸法对总多糖进行含量测定;应用核磁共振氢谱(1H-NMR)分析单糖组成;运用高效凝胶渗透色谱(HPGPC)测定总多糖的分子量分布。结果:以葡萄糖计,4批新式胡桐泪总多糖含量平均值为(7.36±1.74)%,6批老式胡桐泪总多糖含量平均值为(1.53±0.99)%;新式与老式胡桐泪总多糖的单糖组成相似,主要由阿拉伯糖和半乳糖组成,还含有木糖、甘露糖、鼠李糖等,部分样品尚含有较高含量的葡萄糖;新旧类型样品总多糖在分子量分布上存在较大差异。结论:新式胡桐泪的总多糖含量平均值较老式高,以多糖含量为评价指标时,新式样品总体质量较老式更好;应用核磁共振氢谱可以快速、准确地鉴定单糖组成。  相似文献   
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To improve its dissolution, ibuprofen solid dispersions (SDs) were prepared in a relatively easy and simple manner, characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR), and evaluated for solubility, in-vitro drug release and oral bioavailability of ibuprofen in rats. Loss of individual surface properties during melting and resolidification as revealed by SEM micrographs indicated the formation of effective SDs. Absence or shifting towards the lower melting temperature of the drug peak in SDs and physical mixtures in DSC study indicated the possibilities of drug-polymer interactions. FT-IR spectra showed the presence of drug crystalline in SDs. Quicker release of ibuprofen from SDs in rat intestine resulted in a significant increase in AUC and Cmax, and a significant decrease in Tmax over pure ibuprofen. Preliminary results from this study suggested that the preparation of fast dissolving ibuprofen SDs by low temperature melting method using polyethylene glycol 4000 (PEG 4000) as a meltable hydrophilic polymer carrier could be a promising approach to improve solubility, dissolution and absorption rate of ibuprofen.  相似文献   
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