Inconsistent expression of both centromeres of a dicentric Y chromosome in a child with ambiguous external genitalia.

A newborn child with ambiguous external genitalia had evidence of internal female development on the left and internal male development on the right. Blood chromosome analysis showed three cell types: 45,X; 46,XY with the Y being submetacentric and about twice the usual size with two 'centromeric' C bands; and 46,X,dic(Y). Chromosome studies from the skin, uterus, and Fallopian tube showed almost exclusively 45,X cells. This represents the second reported patient in whom two centromeres are inconsistently expressed though present as shown by two 'centromeric' C bands.     

Genetic counseling in ornithine carbamoyltransferase deficiency

Ornithine transcarbamylase (OTC) deficiency is an inborn error of urea cycle metabolism, responsible for lethal hyperammonemia in males and for severe symptoms in at least 20% of heterozygous females. The authors provide here additional data on the informativity of the protein loading test (PLT) for the detection of heterozygotes. They show that the risk of being a carrier for the mother of an affected boy falls from 2/3 a priori to only 1/8 if her PLT is negative. The risk for the mother of heterozygote girl falls from 1/2 a priori to 1/16 if her PLT is negative.     

Effects of social factors on adrenal weight and related physiology of Macaca fascicularis

Increased adrenal cortical activity and hypertrophy of adrenal glands associated with defeat and social subordination have been reported frequently in small mammals; these adrenal changes have been linked to impairments in immune response, glucose metabolism and reproductive performance. Similar studies in primates have produced variable results. The current study was undertaken to illuminate the effects of social status on the adrenal gland and to examine concurrent effects of social variables on other physiological systems in Macaca fascicularis, in an initial exploration of the hypothesis that high and low social status have different physiological consequences. Sixty adult male M. fascicularis were housed in social groups of n = 5, under either stable or unstable social conditions. It was found that subordinate animals had heavier adrenal glands and somewhat higher plasma glucose concentrations than dominants. In contrast, dominants had higher blood pressure and worsened atherosclerosis, under some conditions, than subordinates. These data appear to offer preliminary support for Henry and Stephen's hypothesis of differential arousal of dominant and subordinate animals.     

Community stressors, mediating conditions and wellbeing in urban neighborhoods.

Individual and community measures of stress are related to the presence of depression/demoralization symptoms (Feeling Bad), to positive Wellbeing (Feeling Good) and to the combination of these two (Wellbeing), in an urban sample of 549 adults. The mediation and moderation of these effects by indicators of social support, evaluation of status, and belief variables intended to measure aspects of individual coping tendencies are examined and tested. The findings suggest the absence of moderating effects of any of the support and coping variables on each stressor or on the effects of stressors on Feeling Bad, Feeling Good, and Wellbeing. A number of the variables do, however, have significant main effects, and thus appear to operate directly on the dependent variables, regardless of the presence or level of stress. Differences between apparent effects on Feeling Good and Feeling Bad and the increase in effects for the combination measure are discussed.     

Age effects on executive ability

Heterogeneity of executive tasks has made it difficult to determine whether there are age-related declines in executive functioning. To address this issue, 112 individuals, 20-79 years old, took the California Trail Making Test (CTMT) and the California Stroop Test (CST), subtests of the Delis-Kaplan Executive Function Scale (D. C. Delis, E. Kaplan, & J. H. Kramer, in press) that include measurement of component skills embedded in the executive function tasks. Multiple regression analyses revealed that after controlling for component skills, age had a significant effect on the executive requirement of the CST, namely speed on the interference condition. Age did not affect switching performance on the letter-number condition of the CTMT. Additional analyses revealed that age was significantly associated with commission of certain types of errors. This study confirms the importance of partialing out components in the assessment of multidimensional cognitive tasks, particularly when making age comparisons. It also emphasizes specificity over generalizability when examining the impact of age on cognition.     

Evaluation of the Spot-CAMP test for the rapid presumptive identification of group B streptococci

A rapid Spot-CAMP test was evaluated for its ability to accurately identify colonies of Streptococcus agalactiae (Lancefield Group B) growing on primary sheep blood agar plates. The test uses a beta-lysin-containing filtrate, which is prepared from a broth culture of Staphylococcus aureus. A drop of beta-lysin filtrate is applied adjacent to a suspected group B Streptococcus (GBS) colony and the plate is incubated and then examined for a zone of synergistic hemolysis. The Spot-CAMP test demonstrated 100% correlation with both a Standard CAMP procedure and Lancefield serogrouping. The rapid Spot-CAMP test was easy to perform and inexpensive, and could presumptively identify within 30 minutes colonies of GBS growing on primary isolation plates.     

Rescue of a thymotropic, leukemogenic C-type virus from cultured, nonproducer-lymphoma cells of strain C57BL/Ka mice.

A permanent cell line, BL/RL₁₂-NP, derived from a radiation-induced C57BL/Ka mouse lymphoid tumor, has remained devoid of MuLV expression, except for the rare, sporadic initiation of virus production in some cultures. It can, however, be stably infected by the radiation leukemia virus (RadLV), and the progeny virus population retains the biological and serological properties of the parental RadLV. The cells can also be infected by a B-ecotropic, nonthymotropic, nonleukemogenic C57BL/Ka virus isolate, BL/Ka (B). In the latter situation, the emerging virus particles may exhibit thymotropic and leukemogenic (T+L+) attributes similar to those of RadLV, while retaining at least some of the envelope determinants of BL/Ka (B). These observations suggest that, following productive infection by a nonleukemogenic helper virus, oncogenic sequences endogenous to the non-producer lymphoma cells may be packaged in infectious progeny virions. The data are interpreted as providing strong support for the existence, in radiogenic lymphomas, of defective T+L+ sequences, designated RadLV-O. Possible mechanisms whereby RadLV-O is later expressed as an infectious leukemogenic virus are discussed.     

Mouse homologues of the human AZF candidate gene RBM are expressed in spermatogonia and spermatids, and map to a Y chromosome deletion interval associated with a high incidence of sperm abnormalities

An RNA-binding motif (RBM) gene family has been identified on the human Y chromosome that maps to the same deletion interval as the 'azoospermia factor' (AZF). We have identified the homologous gene family (Rbm) on the mouse Y with a view to investigating the proposal that this gene family plays a role in spermatogenesis. At least 25 and probably >50 copies of Rbm are present on the mouse Y chromosome short arm located between Sry and the centromere. As in the human, a role in spermatogenesis is indicated by a germ cell-specific pattern of expression in the testis, but there are distinct differences in the pattern of expression between the two species. Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are female due to a position effect resulting in non-expression of Sry ; sex-reversing such mice with an Sry transgene produces males with a high incidence of abnormal sperm, making this the third deletion interval on the mouse Y that affects some aspect of spermatogenesis. Most of the copies of Rbm map to this deletion interval, and the Yd1males have markedly reduced Rbm expression, suggesting that RBM deficiency may be responsible for, or contribute to, the abnormal sperm development. In man, deletion of the functional copies of RBM is associated with meiotic arrest rather than sperm anomalies; however, the different effects of deletion are consistent with the differences in expression between the two species.      

Mutations in Emery-Dreifuss muscular dystrophy and their effects on emerin protein expression

Seventeen families with Emery-Dreifuss muscular dystrophy (EDMD) have been studied both by DNA sequencing and by emerin protein expression. Fourteen had mutations in the X-linked emerin gene, while three showed evidence of autosomal inheritance. Twelve of the 14 emerin mutations caused early termination of translation. An in-frame deletion of six amino acids from the C-terminal transmembrane helix caused almost complete absence of emerin from muscle with no localization to the nuclear membrane, although mRNA levels were normal. This shows that mutant emerin proteins are unstable if they are unable to integrate into a membrane. A 22 bp deletion in the promoter region was expected to result in reduced emerin production, but normal amounts of emerin of normal size were found in leucocytes and lymphoblastoid cell lines. This shows that DNA analysis is necessary to exclude emerin mutations in suspected X-linked EDMD. Emerin levels in female carriers often deviated from the expected 50% and this was due, in at least two families, to skewed emerin mRNA expression from the normal and mutated alleles. In one family with a novel deletion of the last three exons of the emerin gene, a carrier had a cardiomyopathy and very low emerin levels (<5% of normal) due to skewed X-inactivation. In the three autosomal cases of EDMD, emerin was normal on western blots of blood cells, which suggests that autosomal EDMD is not caused by indirect reduction of emerin levels.