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41.
42.
Inactivation of rifampin by Nocardia brasiliensis.   总被引:1,自引:3,他引:1       下载免费PDF全文
Rifampin was glycosylated by a pathogenic species of Nocardia, i.e., Nocardia brasiliensis. The structures of two glycosylated compounds (RIP-1 and RIP-2) isolated from the culture broth of the bacterium were determined to be 3-formyl-23-(O-[beta-D-glucopyranosyl])rifamycin SV and 23-(O-[beta-D-glucopyranosyl])rifampin, respectively. Both compounds lacked antimicrobial activity against other gram-positive bacteria as well as the Nocardia species.  相似文献   
43.
BACKGROUND: Bullous pemphigoid (BP) is a subepidermal blistering disease characterized by autoantibodies against the hemidesmosomal proteins, BP180 and BP230. NC16A, a non-collagenous stretch of the BP180 ectodomain is the primary target of pathogenic IgG antibodies. Whereas IgG anti-BP180 autoantibodies play a primary role in the pathogenesis, there is a growing number of data regarding the potential pathogenic roles of IgE class autoantibodies in BP. OBJECTIVES: To examine the levels of IgG and IgE autoantibodies against BP180 and BP230, and to investigate mutual association and clinical relevance. METHODS: Sera obtained from 67BP patients and 36 healthy donors were subjected to ELISA assays to measure serum IgG and IgE levels of anti-BP180 and anti-BP230 antibodies. RESULTS: IgG anti-BP180 antibodies were positive in 63 (94%) of 67BP patients. IgG anti-BP230, IgE anti-BP180, and IgE anti-BP230 antibodies were found in 48 (72%), 20 (30%) and 45 (67%), respectively. IgG anti-BP180 levels were correlated with the affected areas. IgG anti-BP230 antibodies tended to increase in proportion to elongation of disease duration. IgE anti-BP230 levels showed a strong association with local eosinophil accumulation, while the levels were reversely related with the affected areas in BP. CONCLUSIONS: IgE autoantibodies to BP180 and BP230 are detected at high frequencies in BP. IgE anti-BP230 antibodies may have a role in attracting eosinophils to the skin lesions.  相似文献   
44.
Inflammation-based markers predict the long-term outcomes of various malignancies. We investigated the relationship between the modified Glasgow prognostic score (mGPS) and the long-term outcomes of obstructive colorectal cancer in patients who underwent self-expandable metallic colonic stent placement and subsequently received curative surgery. We retrospectively analyzed 63 consecutive patients with pathological stage II and III obstructive colorectal cancer from 2013 to 2018. The mGPS was calculated before stenting and surgery, and the difference of the scores was defined as the d-mGPS. All d-mGPS = 2 patients were > 70 years of age (p = 0.01). Postoperative complications were more common in the preoperative mGPS = 2 group (p = 0.02). The postoperative hospital stay was significantly longer in the mGPS = 2 group (p = 0.007). Multivariate analyses revealed that d-mGPS was an independent prognostic factor for overall survival (OS) (hazard ratio [HR] = 9.18, p = 0.004) and cancer-specific survival (HR = 9.98, p = 0.01). Preoperative mGPS = 2 was significantly associated with poor OS (HR = 5.53, p = 0.04). The results indicated that mGPS might serve as a valuable indicator of the immunonutritional status of preoperative patients, and a preoperative change of the status might affect the long-term outcomes of patients with obstructive colorectal cancer.  相似文献   
45.

Purpose

Pirfenidone is a new, anti-fibrotic drug used for the treatment of idiopathic pulmonary fibrosis (IPF). The aim of this study was to evaluate the utility of computed tomography (CT) in the imaging assessment of the response to pirfenidone therapy.

Materials and methods

Subjects were 78 patients with IPF who underwent CT on two occasions with one-year interval (38 consecutive patients treated with pirfenidone and 40 age-matched control). Changes in the fibrous lesion on sequential CTs were assessed as visual score by two radiologists. We measured the volume and change per year of fibrous pattern (F-pattern) quantitatively using a computer-aided system on sequential CTs.

Results

The baseline vital capacity (%pred VC) was 74.0 ± 14.0% in the pirfenidone group and 74.6 ± 16.6% in controls (p = NS). Deterioration of respiratory status was defined as 10% or greater decline in %pred VC value after 12-month treatment. A significantly larger proportion of pirfenidone-treated patients showed stable respiratory status (21 of 38, 65.6%) than the control (15 of 40, 37.5%). The change in fibrous lesion was significantly smaller in the pirfenidone group than the control in both of visual score (p = 0.006) and computer analysis (p < 0.001). The decline in VC correlated significantly with the increase in fibrotic lesion (p < 0.001).

Conclusion

CT can be used to assess pirfenidone-induced slowing of progression of pulmonary fibrosis.  相似文献   
46.
47.
We analyzed ictal motor symptoms in 10 patients diagnosed to have supplementary motor area (SMA) seizures based on ictal encephalographic (EEG) findings and ictal clinical semiology. Inclusion criteria were (1) EEG seizure pattern in the vertex for the scalp recording or in the area over and/or adjacent to SMA for epicortical recording and (2) ictal motor semiology characterized, as previously reported, by sudden and a brief tonic posturing of extremities and trunk mainly occurring during sleep without loss of consciousness. In 50% (5/10) of the patients, tonic posturing began in one part of the body and moved to other part(s) in 5-10s. Unlike Jacksonian march seen in seizures involving the primary sensorimotor area (S1-M1), it spread in no accordance with the somatotopy in S1-M1. The sequential propagation of tonic posturing may represent the somatotopic organization within the SMA proper.  相似文献   
48.
BACKGROUND: The antitumor activity of CS-1008, a humanized agonistic anti-human death receptor (DR) 5 antibody, was investigated in preclinical models. Materials and methods: Cytotoxicity of CS-1008 was evaluated in a several human tumor cell lines as well as primary human hepatocytes in vitro. To evaluate antitumor efficacy, athymic nude mice were inoculated with human colorectal tumor COLO 205, pancreatic tumor MIA PaCa-2 or non-small-cell lung carcinoma NCI-H2122 and CS-1008 was i.v. administered. The combination effects of CS-1008 with gemcitabine or docetaxel (Taxotere) against MIA PaCa-2 or NCI-H2122 were evaluated in vivo, respectively. RESULTS: CS-1008 inhibited the growth of tumor cell lines with DR5 expression, including COLO 205, NCI-H2122, MIA PaCa-2 and renal cell adenocarcinoma ACHN in vitro with antibody cross-linkage. Using COLO 205, apoptosis induction was confirmed by annexin V staining. Weekly administration of CS-1008 resulted in the inhibition of COLO 205 tumor growth as well as MIA PaCa-2 in vivo. CS-1008 in combination with gemcitabine or docetaxel demonstrated enhanced antitumor activity against MIA PaCa-2 or NCI-H2122 cells, respectively. Unlike tumor necrosis factor-related apoptosis-inducing ligand, CS-1008 did not induce cell death in human primary hepatocytes. CONCLUSION: CS-1008 has a selective toxicity toward tumor cells expressing DR5 and the potential for antitumor efficacy in human malignancies.  相似文献   
49.
Factors influencing collagen-induced autoimmune ear disease   总被引:3,自引:0,他引:3  
In 1981, the authors described a type II collagen-induced autoimmune ear disease (CIAED) model. The purpose of this study was to gather further evidence that this is a sound animal model to use in evaluating inner ear diseases. The temporal bone lesions of CIAED in Lewis and Wistar rats were characterized by the presence of sensorineural hearing loss with mild atrophy of the organ of Corti and spiral ganglion degeneration, vestibular dysfunction with vacuolar degeneration of the crista ampullaris, otospongiosis-like lesions in the tympanic annules, cochlear vasculitis, and eustachian tube disease. Both cellular and humoral immune responses to type II collagen were demonstrated. The induction of ear lesions depends on many factors. In general, animals immunized with antigens in complete Freund's adjuvant showed relatively more severe lesions than animals immunized with antigens in incomplete Freund's adjuvant, but the duration of the immunization seems to be a more important factor in reproducing severe lesions. The strain and the source of the animals are also important factors in autoimmune inner ear diseases, as is the condition of the host animals. Subclinical or clinical mycoplasma infection in the rat markedly reduced the incidence and severity of lesions in type II collagen-induced arthritis. Many researchers did not consider sialoductal adenovirus, widely present among laboratory rats, a lesion-producing factor in rats. Although many factors influence the induction and severity of CIAED, these animal models provide an excellent new avenue of inner ear research.  相似文献   
50.
Induction of experimental endolymphatic hydrops by immunologic techniques   总被引:1,自引:0,他引:1  
Immunologic techniques have been used by many investigators to produce experimental endolymphatic hydrops models. These techniques, however, have achieved little success in producing models simulating the idiopathic endolymphatic hydrops of Meniere's disease, in which no inflammatory changes occur in the perilymphatic spaces. In this study, the antigen horseradish peroxidase (HRP) was injected into the endolymphatic sacs of ninety guinea pigs that had been systematically sensitized to this antigen. Endolymphatic hydrops was induced in sixty-seven of the subjects, sixty-four of which showed no inflammatory changes in the perilymphatic spaces. The endolymphatic sacs of the affected guinea pigs were packed with soft granulation tissue induced by immunologic mechanisms; it is felt that the hydrops was caused by disturbances in endolymph absorption resulting from these tissue formations. Our results suggest that the introduction of antigens into the endolymphatic sac may prove useful in producing endolymphatic hydrops with characteristics similar to those occurring in Meniere's disease.  相似文献   
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