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1.
The presence of certain defects in both cellular and humoral immunity after thermal injury has been established. Likewise, the translocation of enteric bacteria to the mesenteric lymph nodes and to distant organs has also been observed following serious thermal injury. The effects of granulocyte colony-stimulating factor (G-CSF) on bacterial translocation, the small bowel mucosa, and cecal bacterial content were investigated in a rat model of burn wound sepsis in which albino Wistar rats were scalded over 30% of their bodies, after which the lesions were infected by 1×108 colony-forming units (cfu)Pseudomonas aeruginosa. The control group was treated with 5% dextrose solution subcutaneously starting 2 days preburn, while the treatment group received 100μg/kg human G-CSF subcutaneously. On the 4th day post burn all animals were killed to examine the bowel and culture of the mesenteric lymph nodes (MLN), livers, and spleens. No significant differences were observed between the groups regarding the cecal bacterial content and small bowel; however, a difference was seen in the ratio of translocation in the MLN liver and spleen and quantitative MLN cultures. Based on these findings, G-CSF was thus found to be significantly effective in reducing bacterial translocation due to burn wound sepsis.  相似文献   
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BACKGROUND: Mycobacteria are being investigated for modulation of inflammation in asthma and atopic disorders by eliciting particularly strong protective TH1 immune responses. OBJECTIVE: To investigate the long-term effects of intratracheally administered Mycobacterium vaccae on an experimental murine model of asthma. METHODS: BALB/c mice were placed in 4 groups: long-term M. vaccae, M. vaccae, asthma, and control groups. All groups but controls were sensitized intraperitoneally and challenged intratracheally with ovalbumin. The long-term M. vaccae and M. vaccae groups were treated with M. vaccae intratracheally simultaneously during challenges. Finally, mice in the long-term M. vaccae group were rechallenged with ovalbumin nebulization 24 days later. Evaluations of lung histopathologic findings and serum cytokine levels were performed. RESULTS: Comparison of the long-term M. vaccae group with the asthma model group revealed that the number of hyperplasic goblet cells in small and large airways (small airway: P < .05; large airways: P < .01) and thickness of basement membrane in large airways were significantly less in the long-term M. vaccae group. Furthermore, numbers of hyperplasic goblet cells in small airways (P < .05) and basement membrane in the large airway (P < .05), as well as inflammation in small airways (P < .01), were significantly less in the M. vaccae group when compared with the asthma model group. Interferon-gamma secretion from splenocytes of the M. vaccae group was significantly higher than the asthma model and long-term M. vaccae groups. CONCLUSION: Intratracheal administration of M. vaccae exerted a long-lasting ameliorating effect on airway histopathologic features of a murine asthma model.  相似文献   
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Pneumoconiosis was diagnosed by open lung biopsy in two dental technicians who had interstitial lung disease. Mineralogical analysis was performed to investigate the origin of the dust that had been inhaled. A marked accumulation of silicon and phosphorus was found in both cases. The hard metals chromium and cobalt were also found. Dental technician's pneumoconiosis is a complex pneumoconiosis in which such dust and hard metals may play a role.  相似文献   
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We aimed to obtain gamma amanitin with high purity through a purification process and compare toxic effects of alpha, beta, and gamma amanitin. Specific concentrations of the toxins (25, 10, 1, and 0.1?μg/mL) were applied to the C3A human hepatocytes. A MTT test was performed to determine the level of toxicity. Alpha amanitin showed a higher toxicity in 48?h while the lowest toxicity was observed in beta amanitin. The toxicity level of gamma amanitin was found between the alpha and beta amanitin toxicity. Our method is suitable for obtaining gamma amanitin with high purity (>99%) as well as for obtaining alpha amanitin and beta amanitin. Gamma amanitin has been shown to have equal responsibility for toxicity as alpha amanitin in amanita poisoning.  相似文献   
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The aim of this study was to determine if the natural antioxidant foods, dried black grape and garlic, protect against cyclosporine nephrotoxicity. Forty-two Sprague–Dawley rats were given Cyclosporine A (CsA) orally for 10 days, with the antioxidant food supplementation begun 3 days before CsA treatment and continued during the study period (totaling 13 days). In each group (control, CsA alone, CsA plus black grape, CsA plus aqueous garlic extract, aqueous garlic extract alone and black grape alone), there were 7 animals. At the end of the study period, the animals were sacrificed; their kidneys were removed and prepared for biochemical and histopathological investigations. Oxidant (xanthine oxidase enzyme and malondialdehyde) and antioxidant (superoxide dismutase, glutathione peroxidase and catalase enzymes) parameters were measured in the kidney tissues of the groups. Histopathological examinations of the tissues were also performed.

It has been found that CsA creates oxidant load to the kidneys through both xanthine oxidase activation and impaired antioxidant defense system, which accelerates oxidation reactions in the kidney tissue. Supplementation with either dried black grape or aqueous garlic extract led to reduced malondialdehyde level in the kidney tissue possibly, by preventing oxidant reactions. In conclusion, the results suggest that impaired oxidant/antioxidant balance may play part in the CsA-induced nephrotoxicity, and some foods with high antioxidant power may ameliorate this toxicity, in agreement with studies with antioxidant vitamins.  相似文献   
9.

PURPOSE

We aimed to investigate the effectiveness and complications of transthoracic CT-guided biopsy techniques.

METHODS

A total of 94 CT-guided percutaneous transthoracic biopsy procedures performed in 85 patients were retrospectively evaluated. Core biopsy technique was used in 87 procedures and transthoracic fine-needle aspiration biopsy was used in seven procedures.

RESULTS

Diagnostic results were achieved in 79 of 94 biopsy procedures. Pathology results were malignant in 54 patients, suspicious for malignancy in three patients, benign in five patients, and benign nonspecific in 17 patients. Specific diagnoses were obtained in 59 patients (62.8%) using core biopsy, but no specific diagnosis could be reached with transthoracic fine-needle aspiration biopsy. Complications included pneumothorax in 27 patients (28.7%) and parenchymal hemorrhage during and after the procedure in eight patients (8.5%).

CONCLUSIONS

CT-guided percutaneous transthoracic needle biopsy is a highly accurate procedure for histopathological diagnosis of thoracic masses. In addition, percutaneous transthoracic biopsy has an acceptably low complication rate and it reduces the need for more invasive surgical procedures.Since the beginning of the 21st century, lung cancer has been cited as one of the most common causes of death (1). World Health Organization declared lung cancer as the first leading cause of death in men and second in women, among all types of cancers (2).Percutaneous transthoracic biopsies are performed either using fine-needle aspiration biopsy (transthoracic fine-needle aspiration biopsy, TTFNAB) method or using the incisional or core biopsy method. Incisional biopsy and core biopsy are used to obtain a part of tissue from the lesion for histological diagnosis. On the other hand, TTFNAB is used to obtain aspiration material, which is used for cytological examination and lesion diagnosis (3, 4).Indications of transthoracic needle biopsy include solitary and multiple pulmonary nodules, mass lesions, persistent focal infiltration, consolidation, presence of cavities and abscesses, pleural lesions, and mediastinal and hilar mass diagnosis (3, 5).The aim of this study was to investigate the technique, suitability, and complications in CT-guided transthoracic biopsy of lung masses.  相似文献   
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