The effect of a series of fixatives on the AgNOR technique

With increasing interest being shown in nucleolar organizer regions (NORs) in pathology, it was considered of great importance to evaluate the effect of some of the more commonly used and more specialized fixatives on the demonstration of these moieties. NORs can be demonstrated in paraffin sections by a silver technique (AgNOR method) which was developed from a method used by cytogeneticists for the demonstration of NORs in chromosome spreads. The degree of staining is dependent on the fixation regime employed and results may vary greatly from one fixative to another. The fixative schedules and post-treatments used in this study were based on standard sequences from the literature. We have shown that, in general, alcohol-based fixatives give optimal results, Carnoy's fluid being especially recommended. Mercurial and dichromate-containing fixatives were found to have highly detrimental effects on NOR staining. 'Routine' 10 per cent formol saline fixation gave adequate results whereas 10 per cent neutral buffered formalin gave optimal staining, similar to alcohol-based fixation.     

A method for typing strains of Legionella pneumophila serogroup 1 by analysis of restriction fragment length polymorphisms

A restriction fragment length polymorphism (RFLP) typing method for Legionella pneumophila serogroup 1 was developed. The method depended upon the use of cloned EcoR1 fragments from L. pneumophila (Knoxville-1) probing Nci1 restriction fragments of chromosomal DNA. Examination of strains of L. pneumophila which were apparently unrelated showed that inter-strain RFLPs were common, and these formed the basis of the typing scheme. The technique was found to be highly reproducible and discriminatory. When the RFLP data were compared to that obtained by monoclonal antibody (MAb) subgrouping both methods of strain differentiation gave consistent results. The isolates examined by either method were also sub-divided by the alternative technique. The analysis of RFLPs by cloned probes should be of considerable epidemiological value.     

Familial insertional translocation of a portion of 3q into 11q resulting in duplication and deletion of region 3q22.1→q24 in different offspring

The use of elongated prophase and prometaphase chromosome preparations has allowed detection of an insertion of a small segment of 3q into 11q in a kindred with 4 balanced carriers and 8 unbalanced offspring. Those with partial 3q deletion have a true multiple congenital anomalies/mental retardation (MCA/MR) syndrome with an appearance suggestive of the Schwartz-Jampel syndrome.     

Social Stigma,HIV/AIDS Knowledge,and Sexual Risk: A Cross‐Cultural Analysis1

The main aim of this study is to evaluate relationships linking social stigma, HIV/AIDS knowledge, and sexual risk among African American (AA) and South African (SA) college students. One major barrier to HIV prevention efforts is the social stigma associated with HIV/AIDS. Based on the Burkholder et al. (1999) findings, persons who engage in greater stigmatization of persons with AIDS (PWA) and gay people are associated with greater sexual behavior risk for HIV/AIDS. The present study attempted to replicate the Burkholder et al. study using African American and South African college students, but the findings were inconsistent with the aforementioned study. AA respondents had higher social stigma of PWA and gays and higher condom self‐efficacy. While SA respondents were less likely to stigmatize PWA and gay persons and had high‐perceived risk of being infected, they reported engaging in high‐risk sexual behavior. The authors discuss the differences that may account for the dissimilar findings.     

The effect of gonadotrophins with differing LH/FSH ratios on the secretion of the various species of inhibin in women receiving IVF

We have measured secretory patterns of inhibin A, B, total alpha inhibin, pro-alphaC inhibin and oestradiol in women following pituitary suppression who were randomised into two groups to receive either urinary gonadotrophin (25:75 IU/ampoule of luteinizing hormone (LH) and follicle stimulating hormone (FSH; Normegon; n = 11) or recombinant (r)FSH (75 IU/ampoule of FSH alone, n = 16). The women were of similar age (approximately 33 years) and length of infertility (approximately 4 years) and had a normal endocrine evaluation. Plasma FSH, LH, oestradiol, inhibin A, B, pro-alphaC and total alpha inhibin were measured by immunoassay prior to and following gonadotrophin stimulation. Immunoactive FSH, LH and oestradiol blood concentrations following pituitary down regulation were similar in the two groups being <2.0, <3.6 IU/l and <82 pmol/l respectively. The units of FSH given (2230 versus 2764 IU; Normegon versus rFSH), duration of treatment (9.1 versus 9.4 days) and number of follicles of > or =14mm on the day of human chorionic gonadotrophin (HCG) administration (17 versus 14) were also similar. Inhibin A or B concentrations rose similarly during Normegon or rFSH administration, peaking at days 9-11. Total alpha and pro-alphaC inhibin concentrations were lower (P < 0.05) in the rFSH group during days 10 and 11 of treatment being 18.9 +/- 15.9 ng/ml (Normegon) and 4.6 +/- 2.8 ng/ml (rFSH) for total alpha inhibin and 8.5 +/- 6.8 ng/ml (Normegon) and 2.8 +/- 1.6 ng/ml (rFSH) for pro-alphaC inhibin on day 10. Overall, higher total alpha inhibin concentrations were associated with more mature follicles and oocytes, greater fertilization rates and better quality embryos. We conclude that inhibin A and B secretion was similar in both groups and is primarily controlled by FSH, whereas total alpha inhibin and pro-alphaC increased preferentially in the Normegon group over the rFSH group, indicating that they are, in part, stimulated by LH.     

Lysosomal routing of Fc gamma RI from early endosomes requires recruitment of tyrosine kinases.

The high-affinity receptor for immunoglobulin G (Fc gamma RI) plays a central role in the clearance of immune complexes by mediating their internalization and delivery to lysosomes. In monocytic U937 cells, receptor internalization is independent of tyrosine kinase activity. However, the tyrosine kinase inhibitor, genistein, prevents further progress of the receptor to lysosomes and traps it in a sub-plasma membrane early endosome. Similarly, Fc gamma RI expressed in COS cells is able to internalize immune complexes but is unable to translocate to lysosomes. This suggests that Fc gamma RI, whose cytoplasmic tail is devoid of known signalling motifs, must recruit tyrosine kinases via its gamma-chain to achieve lysosomal delivery. We show that a chimera of the extracellular domain of Fc gamma RI and the cytoplasmic tail of the gamma-chain is both internalized and efficiently trafficked to lysosomes. Our study suggests that a key function of the gamma-chain is recruitment of tyrosine kinases to initiate the intracellular signalling pathways required to target Fc gamma RI following immune complex aggregation to lysosomes and not to initiate endocytosis per se.     

Executive function in XXY: Comparison of performance‐based measures and rating scales

Few studies have systematically assessed executive functioning (EF) skills in boys with XXY, and these are limited by small samples and restricted EF assessment. This study used a broader battery of performance‐based measures as well as parent‐rating scales of EF in 77 boys and adolescents with XXY (mean age = 12.5 years), recruited from a clinical trial and an outpatient clinic. Exploratory factor analyses were used to create EF domains from performance‐based measures, and similar domains were measured using the Behavior Rating Inventory of Executive Function and Conners Parent‐Rating Scales. The boys with XXY showed a distinct EF profile, with the greatest deficit in attention and more moderate deficits in working memory, switching, and planning/problem solving. Parent ratings showed similar challenges, as well as impaired inhibition. Independent sample t‐tests showed no difference on performance measures between boys diagnosed or not diagnosed with attention‐deficit/hyperactivity disorder (ADHD), although parents of boys diagnosed with ADHD reported more difficulties. There were no differences on performance‐based tests between those diagnosed pre‐ and postnatally, although parents of postnatally diagnosed boys reported more metacognitive problems. Language deficits, cognition, and socio‐economic status did not account for EF deficits.     

Housing type,housing location and mental health

A number of studies have suggested a connection between the type of dwellings which people occupy and their mental health. People who live in flats are usually shown to be more prone to mental illness than those who live in houses. Those who live in high-rise accommodation are shown to be particularly vulnerable. These conclusions were examined by comparing rates on an indicator of psychological distress, in different dwelling types located in good and bad council housing areas. The results suggest that psychological distress is more closely associated with the location of a dwelling than with dwelling type. High-rise flats located on inner-city problem estates are associated with high levels of psychological distress, while low levels are found in similar dwelling types located in the suburbs. These findings are consistent when the effect of age, health, sex and household class are taken into consideration.     

Safety and efficacy of internal mammary artery grafts for left main coronary artery disease. A preliminary report

Questions regarding the relative safety and efficacy of internal mammary artery (IMA) grafts versus saphenous vein grafts (SVG) in patients with left main coronary artery disease (LMCAD) have not been specifically addressed in the literature. To elucidate this point, we analyzed 196 patients with LMCAD who underwent myocardial revascularization between January 1975 and December 1981, 98 by IMA and SVG and 98 by SVG, IMA was used most often to bypass the left anterior descending (LAD). Chi Square and "t" tests were performed on all demographic, cardiac and operative data comparing IMA to SVG. All results were non-significant, indicating that the two groups were comparable. Anginal pattern was progressive or unstable in 93%. IMA was used in 4 patients who were on intra-aortic balloon pump. The mean number bypass grafts per patient was 3.1. Postoperative complications were comparable for both groups, including early and late myocardial infarction. Overall operative mortality was 2.6%. Results of a survival analysis indicated no significant difference in the mortality rates of patients operated on by SVG versus IMA-SVG. Cumulative mortality rates at a mean followup of 20.5 months were 12.2% for SVG and 7.1% for IMA patients. Significant mortality risk factors were ejection fraction less than 55% (p less than 0.05); and perioperative myocardial infarction (p less than 0.001). Twenty-five patients with recurrent chest pain underwent repeat cardiac catheterization. This revealed 10 of 10 patent IMA grafts, 6 of 8 single patent SVG to LAD and 6 of 9 patent sequential vein grafts to the diagonal and LAD arteries.(ABSTRACT TRUNCATED AT 250 WORDS)