Diabetic glomerulopathies

The archetypal nodular lesion as described in conventional diabetic glomerulopathies is considered, in the view of recent research advances, as a sub-endothelial microangiopathy developed on a peculiar filtration-type basement membrane (type IV collagen, proteoglycans) and early associated with podocytic and mesangial phenotypic alterations. The molecular pathways leading to glucose pathogenic effect are plural, their interactions, biochemical switch off and regulation mechanisms involving a cellular glucose "operon" are better understood and would allow in the next future to superimpose other therapeutic targets to the hemodynamics changes induced by different angiotensin blockades, future interacting key-controls for the renal microvascular as well as coronary and cerebrovascular risks.     

Rhône-Alpes observatory of Streptococcus pneumoniae in 1999: 35 cases of meningitis

In 1999, in Rh?ne-Alpes region, in a survey of resistance to antibiotics of Streptococcus pneumoniae, 35 cases of meningitis were observed. A retrospectic questionnary was sent to each participant. MICs to Penicillin, Amoxicillin and Cefotaxime were determined with ATB-PNEUMO gallery or E-test and by disk diffusion for the other antibiotics. The results were interpreted according to the recommendations of the CA-SFM. Mean age was 38.1 years (range : 1 month -78 years) and sex-ratio 2/5. Eight patients had previously received antibiotics, 22 patients had risk factors and 23 were transferred in intensive care unit. The patients received C3G + glycopeptide in 15 of 16 children and in 13/19 adults according to the consensus recommendations. Diagnostic was made on the direct examination of CSF in 83%, and blood cultures was positive in 74.3% of cases. The percentage of PRP was 48.6% with 17.1% of intermediate-amoxicilline and 14.3% intermediate-cefotaxime strains. Resistance to trimethoprim-sulfamethoxazole was 45.7%, to chloramphenicol 30% and to fosfomycin 6.9%. All the strains were susceptible to rifampicin and vancomycin. Among the 17 PRP strains, 7 were belonging to serotype 6 (6 in children). The clinical outcome was fatal in 7 male cases (20%), without risk factors in 3 children and 6 of 7 strains were susceptible to penicillin. Six patients (17%) had auditive and/or neurologic sequellaes. This study shows that nearly 50% of strains isolated in meningitis, in Rh?ne-Alpes region, were not susceptible to penicillin, and confirms the frequency of sequellaes while the mortality is not related with the resistance of strains to the antibiotics.     

Phenobarbital increases DNA adduct and metabolites formed by ochratoxin A: role of CYP 2C9 and microsomal glutathione-S-transferase

Ochratoxin A (OTA), a mycotoxin that induces nephrotoxicity and urinary tract tumors, is genotoxic and can be metabolized not only by different cytochromes P450 (CYP) but also by peroxidases involved in the arachidonic cascade, although the exact nature of the metabolites involved in the genotoxic process is still unknown. In order to establish the relation between OTA genotoxicity and the formation of metabolites, we chose three experimental models: kidney microsomes from rabbit, human bronchial epithelial cells, and microsomes from yeast that specifically express the human cytochrome P450 2C9 or 2B6 genes. OTA-DNA adducts were analyzed by (32)P postlabeling and the OTA derivatives formed were isolated by HPLC after incubation of OTA in the presence of: (1) kidney microsomes from rabbit pretreated or not with phenobarbital (PB); (2) human pulmonary epithelial cells simultaneously pretreated (or not) with PB alone or in the presence of ethacrynic acid (EA); (3) microsomes expressing CYP 2B6 and 2C9. PB pretreatment significantly increased DNA adducts formed after OTA treatment, both in the presence of kidney microsomes and bronchial epithelial cells, and induced the formation of new adducts. Ethacrynic acid, which inhibits microsomal glutathione-S-transferase, reduced DNA adduct level. DNA adducts were detected when OTA were incubated with microsomes expressing human CYP 2C9 but not with those expressing CYP 2B6. Several metabolites detected by HPLC were increased after PB treatment. Some of them could be related to DNA-adduct formation. In conclusion, OTA biotransformation, enhanced by PB pretreatment, increased DNA-adduct formation through pathways involving microsomal glutathion-S-transferase and CYP 2C9.     

Submaxillary gland androgen-regulated protein 3A expression is an unfavorable risk factor for the survival of oropharyngeal squamous cell carcinoma patients after surgery

Recently, increased expression of the submaxillary gland androgen-regulated protein 3A (SMR3A) was found in recurrent tumors of an orthotopic floor-of-mouth mouse tumor model after surgery. However, SMR3A expression in the pathogenesis of human malignancy and its correlation with the clinical outcome have not been addressed so far. We analyzed tissue microarrays with specimens from oropharyngeal squamous cell carcinoma (OPSCC) patients (n = 157) by immunohistochemistry and compared SMR3A expression with clinical and pathological features by statistical analysis. Strong SMR3A expression was found in almost 36 % of all primary OPSCCs. Although, SMR3A protein levels were not associated with any clinical or histopathological feature tested, univariate Kaplan–Meier analysis revealed a significant correlation between high SMR3A protein expression and poor progression-free (p = 0.02) and overall survival (p = 0.03). Furthermore, high SMR3A expression was an independent marker for poor clinical outcome [HR (SMR3A^high vs. SMR3^low) = 2.32; 95 % CI = 1.03–5.23] concerning overall survival in a multivariate analysis of OPSCC patients with surgery as primary therapy (n = 100). Our data demonstrate for the first time increased SMR3A protein expression in the pathogenesis of OPSCC, which serves as an unfavorable risk factor for patient survival.