Molecular diagnosis of hereditary neuropathy with liability to pressure palsies (HNPP) by detection of 17p11.2 deletion in Italian patients

Hereditary neuropathy with a liability to pressure palsies (HNPP) is an autosomal dominant disorder characterized by recurrent pressure palsies generally precipitated by minor trauma; weakness and paraesthesia usually improve and recover completely in a few months. By Southern blotting and fluorescent in situ hybridization analysis we confirm the presence of a 17p11.2 deletion in familial and in isolated cases of HNPP, suggesting that molecular analysis of the 17p11.2 region could also be a reliable and non-invasive method of diagnosis in sporadic cases, where a correct diagnosis usually requires a nerve biopsy. Although HNPP is a mild disease and not all patients seek medical attention, a presymptomatic diagnosis is useful for assessing the risk during genetic counselling, due to the inheritance of the mutation.     

Alpha 2-adrenoceptor sensitivity in anorexia nervosa: GH response to clonidine or GHRH stimulation

Growth hormone (GH) response to clonidine and growth hormone-releasing hormone (GHRH) stimulation, together with baseline somatomedin C (SmC) levels, were examined in parallel in a group of 21 patients with anorexia nervosa (AN) and in 10 controls. In addition, the Hamilton Rating Scale for Depression (HRS) was administered to the patients. Clonidine (2.5 micrograms/kg body weight, iv) induced GH elevations that were not significantly different between patients and controls. In contrast, GHRH (1 microgram/kg body weight, iv) produced a significantly higher GH response in anorectics than in controls. The ratio between GH responses (area under the curve, or AUC) to GHRH and to clonidine was significantly higher in patients than in controls. Baseline SmC levels (6 patients) were significantly lower in anorectics than in controls. Minor depressive symptomatology was present in all patients. When viewed in relation to the GH hyperresponsiveness to GHRH, the apparent normality of the response to clonidine in anorectics reflects the existence of an actual alpha 2-adrenoceptor subsensitivity. As clonidine reportedly acts via release of endogenous GHRH, an excessive, rather than a normal, GH response to clonidine was to be anticipated.     

Cytomegalovirus Prevalence and Transmission After Islet Allograft Transplant in Patients with Type 1 Diabetes Mellitus

Cytomegalovirus (CMV) serological status of transplant donors and recipients has important implications on antiviral prophylaxis, morbidity/mortality, donor selection and hospital stay. We evaluated CMV prevalence in our islet transplant candidates (ITC) in comparison with organ donors. We correlated the CMV serological status of our ITC with serology for Epstein-Barr virus and Parvovirus B19, auto-antibodies, patient's age, age at DM onset, duration of DM, gender, race, ABO group, HLA haplotype and C-peptide levels. Cytomegalovirus transmission after islet transplant using the Edmonton regimen was also evaluated. Cytomegalovirus seropositivity varied according to patient group, age, gender and race. Type 1 DM patients had reduced odds of CMV seropositivity when compared with organ donors. In all groups studied, older patients, females, and non-Caucasians were more likely to be CMV seropositive. In addition, no CMV reactivation, infection or disease was observed among our transplanted patients using this steroid-free regimen even after donor/recipient CMV mismatch.     

Current status of Milan adjuvant chemotherapy trials for node-positive and node-negative breast cancer

This report summarizes the most important clinical results achieved at the Milan Cancer Institute through various randomized trials with systemic adjuvant chemotherapy. In the study testing surgery versus surgery plus 12 cycles of cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) in node-positive patients, the reduction in failure rate (34%) significantly favored CMF-treated patients (P less than 0.001). Despite a reduction in the death rate of 23%, the overall survival showed only a trend for CMF compared to surgery alone (P = 0.10). In a second study, the 8-year results confirmed the lack of difference in relapse-free survival and total survival rates between patients who received 12 and 6 cycles of CMF. The third study indicated that at 6 years, postmenopausal women who had 1-3 positive lymph nodes and were treated with full-dose sequential non-cross-resistant combinations had rates of relapse-free survival and total survival that were superior to those previously achieved with CMF in the same menopausal subset. In a limited series of patients with negative axillary nodes as well as negative estrogen receptors, there was clear evidence of very poor prognosis in women given only local-regional therapy, compared to women treated with adjuvant CMF. Within the node-negative subset, the proliferative activity (labeling index) of the primary tumor appears to be a more effective prognostic discriminant than estrogen receptor status. The proportion of primary drug-resistant tumor cells as well as the lack of relative dose intensity in the drug programs tested so far probably represent the two most important causes for the failure of adjuvant chemotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hyperhomocysteinemia in premature arterial disease: examination of cystathionine {beta}-synthase alleles at the molecular level

Hyperhomocysteinemia occurs in approximately 30% of the patientswith premature occlusive arterial disease (POAD). Some of theseexhibit significantly reduced fibroblast cystathionine ß-synthase(CBS) activities, suggesting that they may be heterozygous forCBS deficiency. To test this possibility, we studied cDNA derivedfrom four well characterized patients with POAD, exhibitinghyperhomocysteinemia and reduced CBS activities, from four normalcontrols, and from four obligatory heterozygotes for CBS deficiency.Lysates of individual colonies of E.coli, containing full-lengthPCR-amplification products in the expression vector, pKK388.1,were tested for CBS activity. cDNA from at least seven of theeight possible independent POAD alleles encoded catalyticallyactive, stable CBS which exhibited normal response to both PLPand AdoMet. The sequences of all 3'-untranslated regions ofall seven isolated POAD alleles were identical to the normal,wild-type CBS sequences. The results of the expression studieswere confirmed for one POAD patient by determining the full-lengthcDNA sequences for both alleles; these were entirely normalover the complete length of the cDNA. In contrast, the screeningmethod correctly distinguished mutant from normal alleles inall four obligatory heterozygotes studied. We conclude thatCBS mRNAs from POAD individuals are free from inactivating mutations,including all 33 previously identified in heterozygous carriersand homocystinuric patients.     

Continuous venous-venous hemofiltration for the treatment of fluid overload in continuous ambulatory peritoneal dialysis patients

Fluid overload is not infrequent in continuous ambulatory peritoneal dialysis (CAPD) patients. In our experience, extemporaneous continuous venous-venous hemofiltration (CVVHF) was able to correct fluid imbalances refractory to high dose diuretics and hypertonic solutions. We treated 8 of 52 patients (5 females, 3 males, mean age 52 years) on CAPD from 4 to 36 months and with fluid overloads of up to 10 kg. A Biospal SCU/CAVH flat-sheet high-flux hemodialyzer employed for 10 h produced an ultrafiltration rate (QB:150 ml/min) of 11.12 +/- 4.97 ml/min. With an isotonic replacement solution, the filter provided sufficient extraction of small molecules so that CAPD could be interrupted during CVVHF. The procedure appeared well tolerated. This approach reduced the use of hypertonic dialysate, which is not devoid of side effects on ultrafiltration capacity of the peritoneal membrane.     

Different patterns of induction of FGF‐2, FGF‐1 and BDNF mRNAs during kindling epileptogenesis in the rat

Neurotrophic factors (NTF) play important roles in the developing and in the adult brain. NTF involvement in neuronal plasticity is suggested by the modulation of NTF expression patterns in different physiological and pathological situations and by the effects they produce in the adult brain (e.g. axonal sprouting induction and neuroprotection). We used the RNAase protection assay to investigate the expression patterns of some NTFs during amygdala kindling, an animal model of epilepsy in which ‘pathological’ neuronal plasticity appears to occur. After a single kindling stimulation, fibroblast growth factor-2 (FGF-2) mRNA levels were increased in the hippocampus, the cortex and the hypothalamus, whereas they were not significantly altered in the thalamus and the striatum. A single stimulation did not alter fibroblast growth factor-1 (FGF-1) and brain-derived neurotrophic factor (BDNF) gene expression. Fully kindled animals, left unstimulated for a week, did not exhibit any alteration in the mRNA levels for any of the NTFs examined. However, in contrast with the effect of a single stimulation, amygdala stimulation of kindled animals (evoking a generalized tonic-clonic seizure) produced a great increase in hippocampal and cortical BDNF mRNA levels, but FGF-1 mRNA levels were not altered, and FGF-2 mRNA levels were significantly increased only in the cortex. These results suggest that different NTFs can be recruited at different stages of kindling epileptogenesis and, accordingly, may play different parts in the adaptive changes taking place in this experimental paradigm.