Molecular mechanisms modifying the peritoneal membrane exposed to peritoneal dialysis.

Over time, a significant proportion of patients an peritoneal dialysis (PD) develop an increased permeability for small solutes, which induces a faster absorption of glucose, and ultrafiltration failure by early dissipation of the osmotic gradient. Vascular proliferation and vasodilatation of preexisting vessels might represent the structural basis for increased effective peritoneal surface area encountered in these PD patients. Animal models have shown that local release of growth factors and nitric oxide in the peritoneal membrane (PM) may lead to the development of areas of neovascularization and/or submesothelial fibrosis. Long-term exposure to conventional, glucose-based dialysis fluids plays a central role in the pathogenesis of these structural modifications. Glucose degradation products and reactive carbonyl species, which are present both in glucose-based dialysates and uremic plasma, accelerate the formation of the advanced glycation end products in the PM, which may in turn initiate a range of cellular responses including stimulation of monocytes, secretion of inflammatory cytokines, proliferation of vascular smooth muscle cells, stimulation of growth factors, and secretion of matrix proteins. The changes in the PM may also be potentiated by uremia and hyperglycemia per se. These new insights into the molecular mechanisms operating in the PM have provided rationale for novel therapeutic strategies including the development of glucose-free PD solutions and two-chamber bags

Nonimmune Hydrops Fetalis Associated With Genetic Abnormalities

The purpose of this review of the literature on nonimmune hydrops fetalis was to evaluate whether recent clinicopathologic studies have modified the relative incidence of the different associated conditions and the management of these pregnancies. We found 600 cases of nonimmune hydrops fetalis published since 1982. These cases were reviewed with particular attention to genetic causes and were compared with a literature review of 298 cases published before 1982. The mean gestational age at diagnosis varied from 24-29 weeks in the recent series, compared with 31-33 weeks in the earlier series. Genetically transmitted conditions accounted for more than 35% of the fetal and maternal disorders associated with nonimmune hydrops fetalis in the recent series, compared with 21% before 1982. The most frequently identified genetic abnormalities in our review were chromosomal disorders (15.7%), α-thalassemia (10.3%), skeletal dysplasia (4%), arthrogryposis multiplex syndromes (1.8%), multiple pterygium syndrome (1.5%), and lysosomal storage disorders (1.0%). These results confirm the need for systematic chromosome analysis in fetuses with nonimmune hydrops. From this review, we conclude that prenatal noninvasive and invasive techniques combined with detailed pathologic studies have improved the accuracy of diagnosis of the underlying causes of nonimmune hydrops fetalis and have influenced the management of these pregnancies.SCOPUS: re.jinfo:eu-repo/semantics/publishe

BRCA1 and BRCA2 mutations in Belgian families with a history of breast and/or ovarian

Certain familial breast and/or ovarian cancers, specially those diagnosed early, are dominantly heritable and have been linked to mutations in BRCA1 and BRCA2 genes. We have tested 30 women selected from 25 different families with specific criteria. Blood samples were always taken with the informed consent and preliminary interview of the patient by a physicologist specialized in presymptomatic testing. Mutation detection were performed by protein truncation test (PTT), gradient gel electrophoresis (DGGE) and subsequent sequencing. The results showed four frameshift mutations among which three induced truncation of the BRCA1 protein and one of the BRCA2 protein. One of the BRCA1 mutations and the only BRCA2 mutation are prevelant among caucasians. Interestingly, one BRCA1 mutation is shared both by Dutch and French families and another one has not yet been reported. Furthermore, a new unclassified varient was identified. Conclusion: by using specific selection criteria, we have been able to detect BRCA mutations in four out of the 25 families tested. One of the mutations seems to be found only in Belgium. Genetic counselling is being offered to their relatives. (C) 1998 Rapid Science Ltd

Aristolochic acid nephropathy in a Chinese patient: time to abandon the term "Chinese herbs nephropathy"?

The causal role of aristolochic acid (AA) in the so-called Chinese herbs nephropathy (CHN) has been conclusively demonstrated only in the Belgian epidemic. We report a biopsy-proven hypocellular interstitial fibrosing nephropathy in a Chinese patient who had ingested a Chinese herbal preparation bought in Shanghai. The identification of AA in the preparation and of AA-DNA adducts in the kidney tissue unequivocally demonstrates, for the first time, the causal role of AA outside the Belgian epidemic. Because the ingested preparation is very popular in China as an over-the-counter product, our observation raises the possibility that many such cases due to AA might be currently unrecognized in China. AA should be banned from herbal preparations worldwide. All cases of the so-called CHN, in which the causal role of AA has been thoroughly documented, should be further identified as aristolochic acid nephropathy (AAN). The term phytotherapy-associated interstitial nephritis (PAIN) might refer to the other cases associated with phytotherapy without identification, as yet, of the causal agent