A woman carrier of two apparently unrelated reciprocal translocations

Summary Two reciprocal balanced translocations involving chromosomes 2, 9, 12, and 18 were found in the karyotype of a woman with a child showing several congenital malformations at birth.Prenatal cytogenetic diagnosis, performed when a second pregnancy occurred, showed a normal chromosome constitution in the foetus.     

Long-lasting tolerance to alcohol following a history of dependence.

Tolerance to alcohol effects is one of the defining features of clinical alcohol dependence. Here, we hypothesized that the post-dependent state may include tolerance to sedative-hypnotic alcohol actions. To address this question, we used a recently developed animal model in which repeated cycles of alcohol intoxication and withdrawal trigger long-lasting behavioral plasticity. This animal model shares important features with the clinical condition. Animals were exposed to 7 weeks of intermittent alcohol vapor, allowed to recover for 3 weeks, and tested in protracted abstinence to exclude contributions from acute withdrawal. Post-dependent and control rats were injected with a hypnotic dose of alcohol (3 g/kg), and the loss of righting reflex (LORR) was recorded, blood alcohol levels were monitored, and the elimination rate was calculated. Post-dependent animals showed a decrease in LORR. Alcohol metabolism and elimination kinetics did not differ between groups. In conclusion, a history of alcohol dependence induces long-lasting hypnotic tolerance. This process may play an important role in maintaining the dependent state.     

Ring chromosome 10 Associated with multiple congenital malformations

Summary A paracentric inversion of the short arm of chromosome 1 (inv(1)(p22p36)) is reported in a deeply mentally retarded 19-year-old girl and in her normal father.     

Balanced autosomal translocations and ovarian dysgenesis

We report two unrelated women with gonadal dysgenesis, and a (6;15)(p21.3;q15) and a (8;9)(p11.2;q12) balanced translocation, respectively. The patients were of normal stature and showed no phenotypic abnormality or malformation other than ovarian failure. We are not aware of other reports of balanced autosomal translocations associated with gonadal dysgenesis in women. The occurrence of chromosome anomaly and sterility in the two females may be coincidental. However, studies on mouse gametic progression indicate that balanced autosomal translocations can cause oocyte degeneration and reduction of reproductive lifespan. On the basis of these observations, we cannot exclude that the ovarian failure in our patients is the result of oocyte degeneration because of as yet unidentified consequences of the balanced translocations.     

IgM and IgG significant reactivity to Borrelia burgdorferi sensu stricto, Borrelia garinii and Borrelia afzelii among Italian patients affected by Lyme arthritis or neuroborreliosis

Abstract This survey evaluates the specificity of band patterns in immunoblot of sera taken from clinically defined cases of Lyme arthritis and neuroborreliosis, towards three locally isolated strains of Borrelia burgdorferi , belonging to the three species: Borrelia sensu stricto, Borrelia garinii and Borrelia afzelii . To assess specificity, patient sera were statistically ( χ ², P ≤ 0.05) compared with blood donors sera samples. Both IgG and IgM antibodies were considered. The overall reactivity of the three Borrelia strains in IgG immunoblots indicated that ten protein bands were significant, with a different prevalence of some of them in the two groups of patient sera: bands at 60-58, 30–33, 36–37 and 28-27 kDa were markers for neuroborreliosis sera; proteins at 100-83, 72-70 and 18-17 kDa behaved like markers for Lyme arthritis. The IgM Immunoblots revealed significant bands at 100-83, 72-70, 51, 24-21 and 18-17 kDa only with neuroborreliosis sera. Though there were variable band reactivities in each strain, a correlation emerged between the three genospecies and the clinical symptoms: in fact B. afzelii and B. garinii were prevalent in Lyme arthritis sera, (IgG Immunoblots); B. garinii was associated to neuroborreliosis (IgG and IgM Immunoblots); B. sensu stricto was strongly reactive with neuroborreliosis in IgM immunoblots. These data indicate that the three locally isolated strains of Borrelia representing the three genospecies should be used together in immunoblot to detect antibodies elicited in neuroborreliosis and Lyme arthritis.     

Pore-forming and haemolytic properties of the Gardnerella vaginalis cytoiysin

The pleomorphic bacterium Gardnerella vaginalis releases in the culture broth a haemolytic exotoxin (Gvh) which is probably a virulence determinant of this unique bacterium, implicated in gynaecological and urological disorders. This 59kDa cytolysin was purified to homogeneity in just one chromatographic step directly from the culture supernatant, a final specific activity up to 1.9 × 10⁶ HU mg^?1 being obtained. The toxin-induced lesion on human erythrocytes results from the formation of a pore whose radius is approximately 2.4 nm. The damage is inhibited by osmotic protectants and shows a sigmoidal dose-response profile suggesting an aggregation process of haemolysin molecules on the target membrane to create the functional lesion. The extent and the kinetics of haemolysis are strongly dependent on temperature and an activation energy of 64.0 kJ mol^?1 has been derived. Lipid membranes can be very efficient inhibitors of Gvh-haemolysis, being able to bind the toxin quite avidly. The inhibitory effect requires the presence of cholesterol and it is stronger when cholesterol is mixed with negatively charged phospholipids rather than with zwitterionic phospholipids, suggesting that a negative surface potential increases the affinity of the toxin for the lipid bilayer. The functional properties of Gvh have been compared with those of Clostridium perfringens theta-toxin (PFO) and Escherichia coli haemolysin (HlyA), which are representative of widespread haemolysins produced by Gram-positive and Gram-negative bacteria, respectively. The toxin shares several features with the family of the so-called ‘sulphydryl-activated’ cytolysins produced by Gram-positive bacteria, although Gvh does not truly belong to this family, being deactivated by β-mercaptoethanol and being antigenically distinct from them. We report here for the first time the detection in the vaginal fluid of infected women of a specific IgA response against the toxin.