Vascular endothelial growth factor is an autocrine survival factor for neuropilin-expressing breast carcinoma cells

We identify a novel function for the vascular endothelial growth factor (VEGF) in its ability to stimulate an autocrine signaling pathway in metastatic breast carcinoma cells that is essential for their survival. Suppression of VEGF expression in metastatic cells in vitro induced their apoptosis, in addition to inhibiting the constitutively elevated phosphatidylinositol 3'-kinase activity that is characteristic of these cells and important for their survival. Hypoxia enhanced the survival of metastatic cells by increasing VEGF expression. The importance of the VEGF receptor neuropilin was indicated by the ability of a neuropilin-binding VEGF isoform to enhance breast carcinoma survival. Moreover, the expression of neuropilin in neuropilin-deficient breast carcinoma cells protected them from apoptosis. The identification of this VEGF autocrine signaling pathway has important implications for tumor metastasis and therapeutic intervention.     

Gemcitabine following radiotherapy with concurrent 5-fluorouracil for nonmetastatic adenocarcinoma of the pancreas

Gemcitabine has been shown to be an active agent in the treatment of pancreatic cancer. This study was conducted to prospectively examine the tolerance and early efficacy of adjuvant gemcitabine following radiotherapy with concurrent 5-fluorouracil (5-FU) for nonmetastatic pancreatic adenocarcinoma. Twenty-three patients, median age 64 years, were treated with combined modality therapy. Nine patients underwent tumor resection before chemoradiation; 14 patients with locally unresectable tumors received definitive chemoradiation. Radiotherapy utilized four fields to the tumor and lymphatics to 45 Gy, plus a lateral boost to 50.4 Gy. Concurrent 5-FU 500 mg/m(2)/day was administered on days 1-3 and 29-31, followed by 4 months of gemcitabine 1,000 mg/m(2)/week for 3 weeks (fourth week break). Adjuvant gemcitabine was well tolerated. Eighty-three percent of the patients completed three to four cycles. The primary dose-limiting toxicity was leukopenia, which was observed in 10 patients (43%). Nonhematologic toxicities were reported in five patients (22%). There were no cases of gemcitabine-induced radiation recall and there have been no deaths attributed to treatment toxicity. Median follow-up for the 23 patients was 12 months (range, 5-50); the actuarial median survival was 13 months. This report confirms that adjuvant gemcitabine following radiotherapy with concurrent 5-FU for nonmetastatic pancreatic adenocarcinoma can be safely administered.     

Glutamine synthetase activity and expression are not affected by the development of motor neuronopathy in the G93A SOD-1/ALS mouse

ApoI/Fas belongs to the tumor necrosis factor receptor (TNFR) superfamily and mediates cell death in various cell types. Earlier studies from this laboratory have shown that Fas-mediated cell death of glioma cells occur, in part, through the production of reactive oxygen species (ROS). To further dissect the molecular mechanisms that are involved in Fas-induced cell death, we compared gene expression between Fas-treated and saline-treated human neuroglioma H4 cells by using the technique of mRNA differential display. This approach led to the identification of hSCO1, a component of the inner mitochondrial membrane, which is required for the correct assembly, and catalytic function of cytochrome-c oxidase, as a Fas down-regulated gene. The decrease in hSCO1 mRNA expression was time-dependent, becoming most prominent after 4 h of Fas-treatment. Morphological changes observed by confocal microscopy revealed that after 4 h of Fas-treatment, the cells undergo membrane blebbing and early formation of apoptotic bodies. These observations are discussed in terms of their support for an important role of mitochondrial events in Fas-induced apoptosis.     

Mutation screening of manganese superoxide dismutase in amyotrophic lateral sclerosis

Seventy-seven cases of ALS were screened for mutations in the manganese superoxide dismutase gene (SOD2). DNA was extracted from CNS tissue and screened using single stranded conformation polymorphism and heteroduplex analysis. No mutations were identified in the entire coding region of the SOD2 gene. The known polymorphism in the mitochondrial targeting sequence was identified. No association was found between this polymorphism and ALS. A further polymorphism was detected in the intronic sequence upstream of exon 4, though no association with ALS was demonstrated. We therefore conclude that mutations in SOD2 do not appear to cause ALS.     

A study of cytokine gene polymorphisms and protein secretion in renal transplantation

Although there is evidence that cytokine gene polymorphisms are associated with varying quantities of cytokine protein production, the exact role of these polymorphisms in allograft rejection remains unclear. In a previous study, we demonstrated a significant association between high IL-10 secretion in mixed lymphocyte culture (MLC), together with HLA mismatching for at least 4-6 antigens, with the occurrence of acute rejection following renal transplantation. We, therefore, wished to ascertain whether cytokine gene polymorphisms are associated with varying levels of protein secretion and/or allograft rejection in the same group of patients. Cytokine protein secretion in MLC for IL-4, IL-6, IL-10 and IFN-gamma was measured by ELISA in 49 patient-donor pairs. Protein secretion for the above cytokines was also measured in phytohaemagglutinin (PHA) stimulated cultures in 30 normal controls. In both patient and control groups, single nucleotide polymorphism analysis for IL-4 G(-590)T, IL-6 G(-174)C, IL-10 G(-1082)A, IL-10 C(-819)T, IL-10 C(-592)A, TNF-alpha G(-308)A and microsatellite analysis for IFNG (CA repeat) was performed. No correlation was found between cytokine gene polymorphisms and cytokine protein secretion in either mitogen stimulated cultures (control group) or MLC (patient group). In addition, no correlation was demonstrated between cytokine gene polymorphisms and renal allograft rejection.     

Peri-operative risk factors for acute lung injury after elective oesophagectomy

Acute lung injury after oesophagectomy is well recognized butthe risk factors associated with its development are poorlydefined. We analysed retrospectively the effect of a numberof pre-, peri- and post-operative risk factors on the developmentof lung injury in 168 patients after elective oesophagectomyperformed at a single centre. The acute respiratory distresssyndrome (ARDS) developed in 14.5% of patients and acute lunginjury in 23.8%. Mortality in patients developing ARDS was 50%compared with 3.5% in the remainder. Features associated withthe development of ARDS included a low pre-operative body massindex, a history of cigarette smoking, the experience of thesurgeon, the duration of both the operation and of one-lungventilation, and the occurrence of a post-operative anastomoticleak. Peri-operative cardiorespiratory instability (measuredby peri-operative hypoxaemia, hypotension, fluid and blood requirementsand the need for inotropic support) was also associated withARDS. Acute lung injury after elective oesophagectomy is associatedwith intraoperative cardiorespiratory instability. Br J Anaesth 2001; 86: 633–8     

The delivery of surgical cleft care in the United Kingdom

BACKGROUND AND PURPOSE: A national survey of cleft teams was undertaken as part of the Clinical Standards Advisory Group investigation of the current status of cleft care in the United Kingdom (UK). METHODS: Fifty-seven cleft teams were identified, of which 90% responded to the survey. MAIN FINDINGS: Nine cleft teams had been established since 1992. Only one region, Northern Ireland, had a centralised cleft service and, despite 82% of teams having databases, only four were able to produce corroborated evidence of receiving at least 30 annual new referrals during 1995. There was a wide variation in the facilities provided by individual cleft teams--only six teams were able to provide all of the key facilities recommended by the Royal College of Surgeons Steering Group on cleft lip and palate. Facilities such as antenatal and neonatal counselling, protocols for record keeping and long-term treatment were similar for high and low volume teams. High volume teams were more likely to have established links with a full range of specialities including psychology, clinical genetics and paediatrics than low volume teams. CONCLUSION: A national survey of cleft services has demonstrated a need for reorganisation. This is now in process and once established will require continual monitoring and assessment.     

Aquaporins and the surgeon: cautionary tales

Nephrogenic diabetes insipidus (NDI) presents an uncommon but formidable clinical challenge in the surgical patient. Two recent cases of NDI with differing aetiology are presented. These cases and a review of the literature illustrate well the diagnosis, fluid and electrolyte imbalances seen and the strategy of treatment required in the post-operative setting. The central role of the recently discovered aquaporin channels in this condition is briefly outlined. Nephrogenic diabetes insipidus has a diverse aetiology and many of the hazards of the condition are peculiar to the surgical setting. The importance of management in a high dependency environment is highlighted.     

Genetic epidemiology of visceral leishmaniasis in northeastern Brazil

Familial clustering of disease, racial differences in asymptomatic:disease ratios, and studies of mice all point to a genetic component for disease susceptibility in visceral leishmaniasis. Analysis of 87 multi-case pedigrees (824 individuals; 138 nuclear families) from a region of northeastern Brazil endemic for Leishmania chagasi demonstrates a high relative risk ratio (lambda(2S) = 34) to further siblings of affected sibling pairs. Complex segregation analysis using POINTER and COMDS show that all single locus models, as well as polygenic and multifactorial models, provide a significantly (P < 0.001) better fit to the data than a sporadic model. Of the genetic models, the general single locus model was not significantly different from additive or dominant single locus models, all of which gave a gene frequency for the putative disease susceptibility allele of approximately 0.002. The general single locus model was strongly favored (P < 0.001) over a recessive single gene model. Using POINTER, polygenic and multifactorial models were clearly rejected (P < 0.001 in all cases) in favor of the general single locus model. Using COMDS, the analysis was extended to consider two locus models. Results under a general two-locus model did not differ significantly from the dominant, additive, or general single locus models. Under this model, one locus was estimated at a gene frequency of 0.0017, i.e., in the same range as the disease susceptibility locus for the most favored single gene models, with the second locus at a much lower frequency of 0.0002. Hence, the data support the hypothesis that a single major gene may be important in determining disease susceptibility in this population. To identify the gene(s) involved, a genome scan with replication using two subsets of these larger pedigrees with power to detect linkage is in progress.