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1.
The authors have previously reported that homologous immunoglobulin (Ig)G reduces the occurrence of dextran sulfate sodium (DSS)-induced colitis, mainly by suppressing recruitment of immunocompetent cells into colitis lesions. However, the mechanisms of cell recruitment and of its suppression by IgG remain unclear. In addressing these questions, this study focused on the activation of T cells in the presence of macrophages. The authors found that [3H]-thymidine uptake of T cells from DSS-induced colitis mice, but not from normal mice, was significantly enhanced when cultured with DSS-pulsed macrophages. From the profile of cytokine production, it was suggested that T helper 1 (Th1)-type cells become predominant during stimulation. Addition of homologous IgG significantly suppressed T cell proliferation in a dose-dependent manner, while no suppressive effect was observed with heterologous IgG. Mouse IgG F(ab')2, but not Fc, fragments partially mimicked the suppressive effect of whole IgG. These findings provide evidence that Th1-type cells may play an important role in the development of DSS-induced colitis and that homologous IgG exerts its protective action at least in part through the F(ab')2 portion.  相似文献   
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The in-vitro permeability of chemically modified tetragastrin with fatty acids through the rat skin was studied. The permeability of these compounds through intact skin and stripped skin of rat was determined with a Franz-type diffusion cell. The permeation of tetragastrin across the intact skin was improved by chemical modification with acetic acid and butyric acid. However, tetragastrin and caproyl-tetragastrin did not permeate across the intact skin up to the end of experiment. The permeation of tetragastrin across the stripped skin was improved by chemical modification, the skin flux of these acyl derivatives being in the order: acetyl > butyroyl > caproyl. The stability of tetragastrin in skin homogenate was also significantly improved by chemical modification with fatty acids. These results suggest that chemical modification of tetragastrin with fatty acids increases its lipophilicity, which makes it permeable across the stratum corneum. Moreover, the chemical modification reduced the degradation of tetragastrin in the viable skin, resulting an increase in permeation of tetragastrin across the skin.  相似文献   
4.
SUMMARY: Inhibition of mevalonate synthesis by several statins has been shown to suppress DNA synthesis in glomerular mesangial cells. In the present study, we investigated the effect of a new statin, cerivastatin, on fetal calf serum (FCS)-induced DNA synthesis of cultured rat mesangial cells. Cultured rat mesangial cells were stimulated by 10% FCS in the presence or absence of cerivastatin and mevalonate. 5-bromo-2-deoxyuridine (BrdU) incorporation was used to assess DNA synthesis. the present study showed that 10% FCS caused marked stimulation of DNA synthesis in the mesangial cells. Cerivastatin inhibited FCS-stimulated BrdU incorporation in a dose-dependent manner. IC50 was approximately 1 umol/L. Exogenous mevalonate, farnesyl pyrophosphate and geranylgeranyl pyrophosphate significantly prevented the inhibitory effect of cerivastatin on DNA replication. It appears that cerivastatin, by inhibiting the synthesis of mevalonate, may suppress DNA synthesis in the mesangial cells.  相似文献   
5.
We report on two cases of women with locally advanced squamous cell carcinoma of the urethra. Patient 1 also displayed regional lymph node metastasis. Treatment comprised combined radiotherapy to 60 Gy and chemotherapy with 5-fluorouracil and cisplatin. Complete response was obtained in both patients, including the inguinal lymph nodes of Patient 1. Patient 1 experienced recurrent inguinal lymph node metastasis on the contralateral side at 42 months after initial treatment, and the same treatment was performed followed by surgical excision. Both patients remain alive with no evidence of disease, at 12 months after recurrence in Patient 1, and at 27 months after treatment in Patient 2.  相似文献   
6.
We report the case of a female patient with bilateral metachronous adrenocortical cancer who survived long-term after adrenalectomy. In 1991, the patient underwent left adrenalectomy to remove a huge adrenal mass (10 x 9 cm) displaying no hormonal abnormality. Histological diagnosis was adrenocortical cancer. A right adrenal mass (7 x 6 cm) was found 4 years after left adrenalectomy. Right adrenalectomy was performed, and histological diagnosis was again adrenocortical cancer. The patient remains alive with no evidence of disease 8 years after last surgery.  相似文献   
7.
A sesquiterpenoid, 7-hydroxy-3,4-dihydrocadalin, isolated from a Mexican medicinal plant Heterotheca inuloides was evaluated as an antioxidant. This sesquiterpenoid inhibited mitochondrial and microsomal lipid peroxidation induced by Fe(III)-ADP/NADH or Fe(III)-ADP/NADPH. Furthermore, 7-hydroxy-3,4-dihydrocadalin protected red cells against oxidative haemolysis. This sesquiterpene was thus shown to be effective in protecting biological systems against oxidative stresses.  相似文献   
8.
PROBLEM : To determine if patients with unexplained recurrent miscarriage have a deficiency of decidual immunosuppressor cells that produce transforming growth factor β type 2, as has been found in mice with abortion due to rejection and/or trophoblast failure. METHODS : Decidual biopsy specimens were taken as near to the placental attachment site as possible under ultrasound guidance from first trimester legal termination (control) patients with recurrent miscarriage and non-viable pregnancy, and from patients with sporadic missed abortion. The tissue was tested for TGFβ-2+ suppressor cells by in situ hybridization, immunohistochemistry, and analysis of supernatants. RESULTS : TGFβ-2-related suppressor molecules similar but not identical to those identified in pregnant mice were released by decidual lymphoid cells. Fifty percent of 14 recurrent miscarriage patients showed a lack of suppressor cells and 59% were subnormal in comparison to 20 controls and 5 sporadic miscarriage patients, where 80–85% of the patients had detectable suppressor cells. CONCLUSIONS : Suppressor cell deficiency is compatible with a role for rejection and/or trophoblast failure in some patients with recurrent miscarriage. Presence of suppressor cells in most patients with missed abortion (4/5) is compatible with an alternative cause of fetal death, similar to findings reported in genetic fetal death mice.  相似文献   
9.
Microdialysis has been used to determine the concentration of salicylic acid in skin tissue and plasma periodically for 4 h to evaluate the effect of ointment bases on topical and transdermal delivery of salicylic acid. The ointment bases examined were solbase (water-soluble), poloid and white petrolatum (oleaginous), hydrophilic poloid (water in oil (w/o) type emulsion lacking water) and absorptive ointment (w/o-type emulsion containing water). The ointments (0.1 g) containing 25 μmol salicylic acid were applied for 2 h to the surface of rat skin (1 cm2) with (intact) or without the stratum corneum. For intact skin, the extent of topical delivery from different ointments, evaluated by the area under the concentration-time curve (AUC) of salicylic acid in the skin tissue (AUCskin), increased in the order solbase. white petrolatum, poloid, hydrophilic poloid. absorptive ointment. The ratio of AUCskin (topical delivery) to the AUC of salicylic acid in plasma (AUCplasma, transdermal delivery) varied remarkably among the different bases, the greatest ratio being observed for absorptive ointment. When the ointments were applied to skin surface without stratum corneum, AUCskin for solbase was much higher (about 45 times that for intact skin), whereas only a small (two-fold) increase was observed for poloid and hydrophilic poloid and the increase was negligible for white petrolatum and absorptive ointment. For skin without the stratum corneum, the ratio AUCskin/AUCplasma for the different ointments was comparable, although the magnitudes of AUCskin and AUCplasma still varied substantially. The variance of AUC values arises as a result of the different rates of release of salicylic acid from the bases. These results indicate that: the topical and transdermal delivery of salicylic acid in intact skin varies substantially among different ointment bases, and the greatest topical delivery is observed for absorptive ointment; use of absorptive ointment increases the retention of salicylic acid in the stratum corneum; and the stratum corneum functions strongly as a penetration barrier for solbase, moderately for poloid and hydrophilic poloid, and less for absorptive ointment and white petrolatum.  相似文献   
10.
Abstract This study investigated interactions between mucosal lesions and bacterial invasion in ulcerative colitis using the acridine-orange staining method. In all 16 cases of ulcerative colitis, the mucosa was found to be invaded by small rods and cocci. In five of 10 controls, bacteria were seen only adhering to the mucosa and no bacteria were detected in the five remaining cases. It is suggested that the presence of bacteria in the colonic mucosa may be a factor responsible for the persistence or aggravation of ulcerative colitis.  相似文献   
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