Detection of Apoptosis in Peripheral Blood Cells of 31 Subjects Affected by Down Syndrome Before and After Zinc Therapy

Thirty-one patients affected by Down syndrome (DS) were investigated to study the presence of apoptosis in peripheral blood cells in relation to the plasma levels of zinc. Twelve patients had undergone therapy with ZnSO₄, while the remaining 19 were untreated. The presence of programmed cell death was evaluated by means of electron microscopy, in situ nick translation (NT), and agarose gel electrophoresis of DNA. These approaches evidenced the presence of apoptosis in peripheral blood cells of patients before therapy with ZnSO₄, while after zinc supplementation there was a reduction in the number of apoptotic cells. These results suggest that the process of programmed cell death in peripheral blood cells of patients with Down syndrome is related to the plasma levels of zinc ion.     

Clustering of Y chromosome deletions in subinterval E of interval 6 supports the existence of an oligozoospermia critical region outside the DAZ gene.

Y chromosome molecular analysis was performed using the STS-PCR technique in 50 patients with oligozoospermia. Microdeletions of interval 6 of the Y chromosome were detected in seven patients, in six of whom subinterval E was affected. All patients retained the RBM1 and DAZ genes, while in one deletion involved the SPGY gene. The size of the deletion was not apparently related to the severity of the disease. These results suggest the presence of an oligozoospermia critical region on the Y chromosome within subinterval E of interval 6.     

Prevalence of chromosomal abnormalities in 2078 infertile couples referred for assisted reproductive techniques

BACKGROUND: This study analyses the prevalence of karyotype changes and Yq11 microdeletions among couples referred for assisted reproduction techniques. METHODS: Prior to receiving either IVF or ICSI treatment, each partner of 2078 infertile couples was screened for karyotype changes by GTG-banding technique on peripheral lymphocytes. No subject presented with obvious phenotype of chromosomal rearrangement. All the oligo/azoospermic men with normal karyotype were further investigated by PCR for Yq11 microdeletions. RESULTS: Eighty-two out of 2078 couples (3.95%) had one partner carrying a chromosomal change, and 10 out of 202 (4.95%) men showed Yq11 microdeletions. The chromosomal rearrangements were 44 (2.1%) translocations, 23 (1.1%) gonosomal mosaics, six (0.3%) 47,XXY, five (0.24%) marker chromosomes, three (0.14%) inversions and one (0.05%) duplication. Frequency of anomalies in men and women were similar: 42 and 40 cases respectively. CONCLUSIONS: Partners of infertile couples requiring IVF or ICSI treatment appear to be affected by higher frequency of chromosomal rearrangements than the general population. Categories with greater risk were represented by men with sperm cell count <20 x 10(6) sperm/ml, and women with history of pregnancy loss.     

Chromosome abnormalities in breast fibroadenomas

A cytogenetic study on 25 breast fibroadenomas from 17 women is reported. Seven tumors in five patients showed clonal structural chromosome changes. In three patients the breaks involved chromosome 12, occurring in two tumors in band 12p12 and in band 12q15 in all three tumors of one patient. The finding of an identical aberration, t(11;12)(q21;q15), in three adenomas from the same patient strongly suggests a clonal origin of multiple fibroadenomas of the breast.     

Variable-ratio schedules of timeout from avoidance: effects of anxiolytic drugs

Concurrent performances in rats were studied under conditions where responses on one lever postponed shock on an unsignaled avoidance schedule, and responses on another level produced periods of signaled timeout from avoidance on a variable-ratio schedule. This procedure resulted in relatively high rates of responding on the timeout lever, and provided a baseline which permitted simultaneous evaluation of drug effects on two different types of negative reinforcement (shock postponement vs timeout). Chlordiazepoxide and ethanol selectively increased responding on the timeout lever at low doses, while higher doses decreased responding on both levers. Two 5-HT(1A) agonists, buspirone and 8-OH-DPAT, had different effects. Buspirone decreased responding across all effective doses, but 8-OH-DPAT increased responding on both the timeout and avoidance levers, with greater increases noted in responding maintained by timeout. These results replicate and extend previous findings, and support the notion that traditional anxiolytic drugs like chlordiazepoxide and ethanol may increase the reinforcing properties of escape from an avoidance schedule. Differences between the behavioral effects of buspirone and 8-OH-DPAT may reflect differential activity at the 5-HT(1A) receptor or the dopaminergic properties of buspirone.     

Synthesis and Ring‐Opening Polymerization of Cyclic Butylene 2,5‐Furandicarboxylate

A new synthetic pathway for the polymerization of furan based polyesters is reported in this work. First, poly(butylene 2,5‐furandicarboxylate) cyclic oligoesters (COEs) are chemically synthesized by semi‐batch esterification. The structure of the COEs is confirmed by infrared spectroscopy, ¹H, and ¹³C‐NMR, while the molecular weight distribution of the COEs is determined by matrix‐assisted laser desorption/ionization time of flight mass spectroscopy. The cyclic oligoesters are then successfully polymerized via ring‐opening polymerization using tetrakis(2‐ethylhexyl)‐titanate as catalyst. Differential scanning calorimetry and ¹H‐NMR analysis unambiguously proves the formation of polymeric species. Both end‐group analysis from ¹H‐NMR spectrum and calculation through Flory–Fox equation give comparable estimates of the number average molecular weight: 5.8 × 10³ g mol^?1 and 7.8 × 10³ g mol^?1, respectively.