When and why does occlusion of the vas deferens affect the testis?

The motility of spermatozoa from successive segments of human and animal epididymides was examined under the phase-contrast microscope. The segments were taken from laboratory rodents unilaterally vas ligated for three to five months and from human orchiectomy specimens. Evidence for testicular alteration, caused by epididymal stasis proven by the phase-contrast motility profile, was sought by weight, gross observation, and histologic examination. Two observations were made on the animals: (1) the ligature about the vas seldom resulted in epididymal stasis because the ligature cut through the muscular wall of the vas (permitting a leak);and, (2) when stasis was achieved, gross and microscopic alterations of the testis from the normal were inevitable. The observations of the human material showed that a progressive loss of sperm motility during passage through the epididymis occurred in more than one half the specimens. The motility profile of these epididymides closely resembled that seen in the unilaterally vas-ligated animals. The suggestion is made that senescence of a testicle may be caused by occlusion of its excurrent ducts. These observations seemed to support the hypothesis that faulty sperm transport and faulty maturation, becuase of epididymal rupture and fibrosis (rather than the presence of autoantibodies to sperm) probably cause the unreliability of vasovasostomy. Storage of frozen semen offers more certainty than the possibility of successful vasovasostomy.     

The Psychometric Detection of Schizotypy: Do Putative Schizotypy Indicators Identify the Same Latent Class?

The authors examined whether three indicators of Schizotypy, the Revised Social Anhedonia Scale (RSAS), Magical Ideation Scale (MIS), and Perceptual Aberration Scale (PAS), identify a common latent class or taxon as conceptualized by P. E. Meehl (1962, 1990). The separate and joint latent structures of these scales were evaluated using taxometric methods in two large, independent samples. Replicating prior findings, the RSAS and PAS each identified latent taxa with base rates approximating .10. Results for the taxonicity of the MIS were less consistent. Analyses of joint latent structure indicated that the RSAS-identified taxon was essentially independent of constructs measured by the PAS or MIS. Measures commonly thought to tap the same latent class, conjectured to be schizotypy, do not share this property. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of anger and relaxation forms of in vivo emotive imagery on pain tolerance.

To examine the effects of "in vivo' emotive imagery on pain tolerance, 40 male and 40 female college students were stratified on sex and assigned randomly to no-treatment control, neutral imagery, anger emotive imagery, or relaxation emotive imagery conditions during which they were asked to immerse their hands in ice water (0 °C) for as long as possible. A sex by treatment analysis of variance followed by Tukey post hoc comparisons showed that anger "in vivo' emotive imagery was significantly more effective for females than no-treatment control procedures. No significant differences were noted in males. (French summary) (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Deafness in Black children is Southern Africa

An aetiological survey of 499 deaf Black children in 3 schools in Southern Africa is reported. Specific genetic syndromes were identified in 21 children, of whom 13 had the Waardenburg syndrome. Inherited deafness without associated defects was diagnosed in further 32 children, and an indentifiable acquired cause was evident in 108 children (22%). No cause could be found in the remaining 338 children (68%), of whom 71 had various nonspecific congenital anomalies.     

Die-off of enteric bacterial pathogens during mesophilic anaerobic digestion

Conventionally treated sewage sludge may contain high concentrations of potentially pathogenic microorganisms and additional treatment is required to minimise the risks to health if it is to be recycled to agricultural land. Mesophilic anaerobic digestion (MAD) is the most widely used process in the UK for stabilising sludge prior to agricultural recycling, but little is known about the fate of a number of enteric pathogens as the sludge passes through the treatment processes. The aim of this study was to determine the efficiency of MAD in removing the bacterial enteric pathogens, Salmonella senftenberg, Listeria monocytogenes and Campylobacter jejuni which were added as a spike to the digester feedstock, together with the die-off of indigenous Escherichia coli already present in the sludge. The primary sludge digestion stage of MAD was found to achieve a log removal of 1.66 for E. coli, 2.23 for L. monocytogenes and 2.23 for S. senftenberg. However, the extent of die-off was a function of the numbers of pathogens in the feed and as these increased the log removal also increased. The numbers of C. jejuni were not affected by primary sludge digestion. Additional die-off was provided by secondary sludge digestion with log removals of 1.70 for E. coli, 2.10 for S. senftenberg and 0.36 for C. jejuni.     

Diagnostic differences in social anhedonia: A longitudinal study of schizophrenia and major depressive disorder.

This study examined the hypothesis that, in schizophrenia, elevated trait social anhedonia (SA) is a stable individual difference, whereas in depression, increased SA is a reflection of a current clinical state that will diminish with recovery. Differences in trait Negative Affect (NA) and Positive Affect (PA) were also examined. Individuals with schizophrenia (n?=?55) and depression (n?=?34) were evaluated at baseline during hospitalization and compared with nonpsychiatric control participants (n?=?41). Participants were assessed again at a 1-year follow-up. At baseline, compared with control participants, individuals with schizophrenia and depression were both characterized by elevated SA, greater NA, and lower PA. In schizophrenic individuals, elevated SA remained stable over the follow-up. However, in recovered depressed patients, SA declined over the follow-up period. Group differences remained in NA and PA over the 1-year follow-up. These results support the view that elevated SA is enduring in schizophrenia but that elevated SA is transiently related to clinical status in depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of death within 11 years on cognitive performance in old age.

Six different cognitive tests and the Beck Depression Inventory (BDI) were given to 3,572 active community residents aged 49 to 93 years. Causes of death were ascertained for 443 who died between 36 and 3,903 days later. Subsequent survival predicted test scores during the 3,903 days and independently during Days 36 to 1,826 and Days 1,827 to 3,903. Scores on the BDI and cumulative verbal learning and vocabulary tests predicted mortality after demographics and performance on other cognitive tests had been considered. Predictors were similar for deaths from heart disease, malignancies, and other causes. A new finding that cognitive tests did not predict survival duration within the sample of deceased explains previous findings of greater terminal decline in performance for young than for elderly adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nicotine poisoning and rapid smoking.

Notes that there are some similarities between nicotine poisoning and symptoms experienced by Ss after rapid smoking (RS). Pharmacological evidence suggests that nicotine poisoning may be the aversive component in the RS paradigm and that hazardous dosage levels are theoretically possible. The need for normative data on the amount of nicotine absorbed by Ss during RS is emphasized, along with methodological issues related to the use of low-nicotine cigarettes and whether the curtailment of nicotine content would weaken the efficacy of the RS treatment. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Parastremmatic dwarfism

The number of ribosomal RNA cistrons has been measured in the total DNA extracted from L2 juvenile and adult stages of the free-living nematode Panagrellus silusiae. Saturation hybridization studies with homologous rRNA indicate that both stages have about 275 ribosomal genes per haploid equivalent. Using homologous 125I-labelled rRNA for in situ hybridization, the mean number of silver grains per DNA content for oocyte, hypodermis and gut nuclei was similar. The mean DNA contents of maturing oocyte, hypodermis and gut nuclei are about 20C, 2C, and 10C respectively. We conclude that rDNA amplication alone is insufficient to account for the variation in DNA content of oocytes and that postembryonic development in this eutelic organism occurs without a significant differential increase in the number of ribosomal cistrons per worm.