Inhibition of dapsone-induced methaemoglobinaemia in the rat isolated perfused liver

We have investigated the disposition of dapsone (DDS, 1 mg) in the rat isolated perfused liver in the absence and the presence of cimetidine (3 mg). After the addition of DDS alone to the liver there was a monoexponential decline of parent drug concentrations and rapid formation of DDS-NOH (within 10 min) which coincided with methaemoglobin formation (11.7 +/- 3.0%, mean +/- s.d.) which reached a maximum (22.6 +/- 9.2%) at 1 h. The appearance of monoacetyl DDS (MADDS) was not apparent until 30-45 min. Addition of cimetidine resulted in major changes in the pharmacokinetics of DDS and its metabolites. The AUC of DDS in the presence of cimetidine (1018.8 +/- 267.8 micrograms min mL-1) was almost three-fold higher than control (345.0 +/- 68.1 micrograms min mL-1, P less than 0.01). The half-life of DDS was also prolonged by cimetidine compared with control (117.0 +/- 48.2 min vs 51.2 +/- 22.9, P less than 0.05). The clearance of DDS (3.0 +/- 0.55 mL min-1) was greatly reduced in the presence of cimetidine (1.03 +/- 0.26 mL min-1 P less than 0.01). The AUC0-3h for DDS-NOH (28.3 +/- 21.2 micrograms min mL-1) was significantly reduced by cimetidine (8.1 +/- 3.40 micrograms min mL-1, P less than 0.01). In contrast, there was a marked increase in the AUC0-3h for MADDS (32.7 +/- 25.8 micrograms min mL-1) in the presence of cimetidine (166.0 +/- 26.5 micrograms min mL-1 P less than 0.01). The methaemoglobinaemia associated with DDS was reduced to below 5% by cimetidine. Hence, a shift in hepatic metabolism from bioactivation (N-hydroxylation) to detoxication (N-acetylation) caused by cimetidine, was associated with a fall in methaemoglobinaemia. These data suggest that the combination of DDS with a cytochrome P450 inhibitor might reduce the risk to benefit ratio of DDS.     

Antibacterials. synthesis and structure-activity studies of 3-aryl-2-oxooxazolidines. 4. Multiply-substituted aryl derivatives.

The synthesis and structure-activity relationship (SAR) studies of the effect of different polysubstitution patterns in the aromatic ring of 5-(acetamidomethyl)oxazolidinone antibacterials (I) on antibacterial activity are presented. Compounds I were prepared by the six-step synthesis described previously (Gregory, W. A.; et al. J. Med. Chem. [formula: see text] 1989, 32, 1673), electrophilic aromatic substitution reactions of 3-substituted compounds, and functional-group interchange reactions of 3,4-disubstituted compounds. Antibacterial evaluation of compounds I against Staphylococcus aureus and Enterococcus faecalis gave the following results. The 2,4- and 2,5-disubstituted derivatives have weak or no antibacterial activity. Antibacterial activities of 3,4-disubstituted compounds are comparable to those of the 4-monosubstituted analogues for small 3-substituents (smaller than Br), but decline rapidly for larger 3-substituents. 3,4-Annulated derivatives are comparable in activity to their open-chain analogues. 3,5-Disubstituted and 3,4,5- and 2,4,6-trisubstituted derivatives are devoid of antibacterial activity.     

Reduction of flurazepam's antiseizure efficacy persists after stress.

Twenty-four hours after mice were forced to swim for up to 10 min in cold (6 degrees C) water, the ability of flurazepam to antagonize the electrical precipitation of seizures was reduced. This stress-induced reduction in flurazepam's antiseizure efficacy persisted for at least 72 h; but was absent 1 week after the single session of swim stress. The data may be relevant to stress-related psychiatric disorders and suggest that the therapeutic efficacy of benzodiazepines may be altered after a severe stress.     

Recognition and management of patients with high-risk vesicovaginal fistulas: Implications for teaching and research

Vesicovaginal fistulas (VVFs) occurring as a result of obstetric trauma are a vast problem in Nigeria and Ghana, where at least 20 000 women await repair, and fewer than 50 physicians have the necessary expertise. Through a series of conferences those VVFs that are at high risk and those at low-risk for repair failure, were identified. A clinic was established where repair of low-risk VVFs was done on an ongoing basis in a remote region of Ghana. A visiting surgical team was utilized to repair the difficult, or high-risk, VVFs, which included 4–6 cm VVFs (3), recurrent VVF (1), combined VVF and RVF (rectovaginal fistula), a large 5 cm juxtacervical VVF (1), and a vesicouterine fistula (1). Management of these patients and others with VVF repair complications is discussed.     

Infracture Technique for the zygomatic body and arch reduction

In the Orient, prominent malar regions are considered unaesthetic and the majority of women with a prominent malar want to reduce the zygoma. Various operative procedures such as shaving or chiseling the zygomatic body or the zygomatic arch have been used for reducing malar eminence, but the zygomatic arch cannot be reduced sufficiently by these methods. By combining intraoral shaving of the zygomatic body and a new effect arch infracture technique through a temporopreauricular incision, we have obtained very satisfactory results in 19 cases and notable minimal complications over the last three years.     

Should all the N3 lymph nodes group metastasis be regarded as distant metastasis (M1) in curatively resected gastric cancer?

Recently, metastasis to N3 lymph nodes group was regarded as distant metastasis by the new TNM staging system due to poor overall survival. However, the 5-year overall survival rate of patients with metastasis to N3 groups was 34.5% after curative surgery. Moreover, in patients with metastasis to lymph node subgroups of #12, #13, #14, the overall 5-year survival rate increased upto 47.2% after curative resection and adjuvant chemotherapy. This was similar to that of the patients with metastasis to N1 and N2 lymph nodes groups. But in these highly tumor burden states, no survival benefit was found with the addition of immunotherapy to chemotherapy as we achieved in stage II and III. Therefore, we suggest that, at least, metastasis to #12, #13, #14 lymph nodes subgroups should not be categorized as a distant metastasis. And in these situations, active curative radical surgery with extended lymphadenectomy and adjuvant chemotherapy are recommended.     

前额迟发性小汗腺血管瘤性错构瘤

一71岁韩国男性前额出现孤立的红色斑块。该斑块出现已有1年,并缓慢增大。体检发现前额上正中线部有一轻微隆起的、1.5cm×1.5cm红色斑块。体力活动或情绪应激反应均不诱发该斑块出汗。皮损无疼痛或触痛。患者前额部无外伤史。皮损组织病理检查示外分泌腺数目增加,真皮深部和皮