Identification of marker chromosomes and translocations in man using a computerized diagnostic database and fluorescent in situ hybridization

BACKGROUND: Many species of bats have two sets of submandibular glands, principal and accessory. The accessory gland may resemble the principal one but more often shows wide morphological divergence. The free-tailed bat, Tadarida thersites, is very unusual in that it has two sets of parotid glands rather than binary submandibular glands. We studied the ultrastructure of the principal parotid gland to establish a baseline for comparison with the accessory parotid. METHODS: Two specimens of adult free-tailed bats, one male and one female, were live-trapped in western Kenya. Parotid glands were fixed for electron microscopy using a protocol expressly designed for field fixation and then embedded by conventional means. RESULTS: Histologically, the principal parotid is a typical serous gland. The secretory granules of the endpiece cells have an unusual substructure in that they contain variable numbers of lucent halos and one or several spherules. Intercalated duct cells contain a significant number of dense, serous-like granules. Striated ducts have the usual basal configuration of mitochondria and folded plasma membranes, but the supranuclear cytoplasm contains many small, dense granules, so that these ducts resemble the granular convoluted tubules found in the submandibular glands of many families of rodents. The apices of the duct cells have a peculiar contour--the luminal surfaces obliquely invaginate into the apical cytoplasm, so that in thin section the luminal membranes appear to be underlaid by a layer of vacuoles. CONCLUSION: Although the principal parotid gland of the free-tailed bat shows some distinctive, species-specific ultrastructural features, it basically is similar to the parotid gland in two other molossid bats, Tadarida brasiliensis and Molossus molossus. The distinctive features in the principal parotid gland of T. thersites might relate to its feeding on hard-bodied insects and perhaps to the production of lysozyme.     

Biomechanical regularities in the distribution of tension in various topographic zones of the eyelids in children in health and myopia of different degree

The authors assessed the method for life-time study of the biomechanical characteristics of ocular tissues in 281 children (562 eyes) aged 7 to 14 years. The method for assessing the biomechanics of the eyelids is described. In detail. The rates of propagation of acoustic waves in normal tissue and in 1.0 to 6.0 diopters myopia are presented. A correlation has been revealed between the increase of the velocity of acoustic surface waves, propagating in the horizontal direction in the internal segment of the orbital area of the upper eyelids, and the value of clinical refraction in myopia. The authors consider clinical signs of myopia-screwing up one's eyes and a wider lid slit-from a biomechanical viewpoint.     

Diagnosis of hemostasis disorders in young children using turbidimetry

Practical application of turbidimetrical method for the diagnosis of haemostasis disorders in babies with acute intestinal infections (AII) is described. The results of plasma biochemical analysis show that disturbances in balance between coagulation and fibrinolytic systems takes place in patients with this pathology. The correlation between biochemical parameters and clinical characteristics is observed. As follows from our data, the phase of the haemostasis disorders in babies with AII does not depend on etiology of the disease, but indicates its severity.     

Benefits of collecting local data on breast cancer and mammography practices in northwestern Pennsylvania

OBJECTIVES: A randomized trial was conducted to evaluate the effectiveness of a work-site health promotion program in reducing obesity and the prevalence of cigarette smoking. METHODS: Thirty-two work sites were randomized to treatment or no treatment for 2 years. Treatment consisted of health education classes combined with a payroll-based incentive system. Evaluation was based on cohort and cross-sectional surveys. RESULTS: Of 10,000 total employees in treatment work sites, 2041 and 270 participated in weight control and smoking cessation programs, respectively. Weight losses averaged 4.8 lbs, and 43% of smoking participants quit. Net 2-year reductions in smoking prevalence in treatment vs control work sites were 4.0% and 2.1% in cross-sectional and cohort surveys, respectively. No treatment effect was found for weight. Treatment effects for smoking prevalence and weight were both positively correlated with participation rates in the intervention programs (r = .45 for smoking and r = .55 for weight). CONCLUSIONS: This work-site health promotion program was effective in reducing smoking prevalence at a cost that is believed to make the investment worthwhile.     

Site-directed mutagenesis of recombinant human beta 2-glycoprotein I identifies a cluster of lysine residues that are critical for phospholipid binding and anti-cardiolipin antibody activity

beta2-Glycoprotein I (beta2GPI) is a phospholipid-binding serum protein with anticoagulant properties. It plays a vital role in the binding of anti-cardiolipin Abs purified from patients with autoimmune disease when assayed in a cardiolipin (CL) ELISA. Based on a three-dimensional model of beta2GPI, electrostatic calculations, and earlier peptide studies, a highly positively charged amino acid sequence, Lys282-Asn-Lys-Glu-Lys-Lys287, located in the fifth domain of beta2GPI, has been predicted to be the phospholipid binding site. We tested this hypothesis by site-directed mutagenesis of residues in the predicted phospholipid binding site and by assessing the mutants for phospholipid binding and anti-beta2GPI activity. A single amino acid change from Lys286 to Glu significantly decreased the binding of beta2GPI to CL. Double and triple mutants 2k (from Lys286, 287 to Glu286, 287), 2ka (from Lys284, 287 to Glu284, 287), and 3k (from Lys284, 286, 287 to Glu284, 286, 287) possessed no binding of Ab to beta2GPI in a CL ELISA, as well as no inhibitory activity on the binding of iodinated native beta2GPI to CL. These results indicate that the residues Lys284, Lys286, and Lys287 in the fifth domain of beta2GPI are critical for its binding to anionic phospholipids and its subsequent capture for binding of anti-beta2GPI Abs.     

Breast cancer screening of the medically underserved: results and implications

Socioeconomic status is the most significant factor influencing the decreased survival associated with breast cancer in minority groups in the United States. Barriers to the use of early detection programs by low-income women often result in the detection of breast cancer at stages too advanced to assure optimum outcomes. In an effort to increase accessibility of breast cancer screening among such individuals, the Early Detection Program (EDP) was initiated in 1987. The program provided breast cancer screening to women 40 years of age and older who attended eight primary healthcare centers located in low-income neighborhoods throughout Dade County, Florida. From its inception in October 1987 through December 1993, 23,866 medically underserved women had mammography examinations, with more than 17,000 of these women undergoing baseline mammograms. Since the program's inception, 126 cancers were diagnosed in 123 women. A dramatic shift from later to earlier stage breast cancers was observed. These results warrant a greater inclusion of medically underserved and lower socioeconomic status women in screening programs for the early detection of breast cancer.     

An endo-acting proline-specific oligopeptidase from Treponema denticola ATCC 35405: evidence of hydrolysis of human bioactive peptides

An endo-acting proline-specific oligopeptidase (prolyl oligopeptidase [POPase], EC 3.4.21.26) was purified to homogeneity from the Triton X-100 extracts of cells of Treponema denticola ATCC 35405 (a human oral spirochete) by a procedure that comprised five successive fast protein liquid chromatography steps. The POPase is a cell-associated 75- to 77-kDa protein with an isoelectric point of ca. 6.5. The enzyme hydrolyzed (optimum pH 6.5) the Pro-pNA bond in carbobenzoxy-Gly-Pro-p-nitroanilide (Z-Gly-Pro-pNA) and bonds at the carboxyl side of proline in several human bioactive peptides, such as bradykinin, substance P, neurotensin, angiotensins, oxytocin, vasopressin, and human endothelin fragment 22-38. The minimum hydrolyzable peptide size was tetrapeptide P3P2P1P'1, while the maximum substrate size was ca. 3 kDa. An imino acid residue in position P1 was absolutely necessary. The hydrolysis of Z-Gly-Pro-pNA was potently inhibited by the following, with the Ki(app) (in micromolar) in parentheses: insulin B-chain (0.7), human endothelin-1 (0.5), neuropeptide Y (1.7), substance P (32.0), T-kinin (4.0), neurotensin (5.0), and bradykinin (16.0). Chemical modification and inhibition studies suggest that the POPase is a serine endopeptidase whose activity depends on the catalytic triad of COOH ... Ser ... His but not on a metal. The amino acid sequence around the putative active-site serine is Gly-Gly-Ser-Asn-Pro-Gly. The enzyme is suggested to contain a reactive cysteinyl residue near the active site. Amino acid residues 4 to 24 of the first 24 N-terminal residues showed a homology of 71% with the POPase precursor from Flavobacterium meningosepticum and considerable homology with the Aeromonas hydrophila POPase. The ready hydrolysis of human bioactive peptides at bonds involving an imino acid residue suggests that enzymes like POPase may contribute to the chronicity of periodontal infections by participating in the peptidolytic processing of those peptides.     

Increased expression of CD80, CD86 and CD70 on T cells from HIV-infected individuals upon activation in vitro: regulation by CD4+ T cells

T cells express CD28 and CD27 which transduce co-stimulatory signals after interaction with their ligands on antigen-presenting cells (APC). These ligands, CD80, CD86 and CD70, are also expressed to some extent on activated T cells. Here, we show that in human immunodeficiency virus (HIV)-infected individuals, CD28 and CD27 expression is decreased on CD8+ T cells. On the other hand, T cell stimulation in vitro induced high CD80, CD86 and CD70 expression on T cells from HIV-infected individuals. It appeared that an inverted CD4:CD8 T cell ratio could explain this enhanced expression of co-stimulatory ligands. Indeed, high expression levels of CD80, CD86 and CD70 were found on activated CD8+ T cells from HIV- individuals cultured in the absence of CD4+ T cells. Addition of CD4+ T cells prevented this up-regulation. However, in HIV-infected individuals, addition of excess autologous or healthy control CD4+ T cells did not completely counteract up-regulation of co-stimulatory ligand expression on CD8+ T cells. Thus, to some extent, CD8+ T cells in HIV-infected individuals appeared to be refractory to CD4+ T cell-mediated regulation of ligand expression in vitro. Activated T cells from HIV-infected individuals and activated CD8+ T cells from healthy controls were able to act as accessory cells in CD3-induced T cell proliferation, which was dependent on cell-cell contact. Thus, we showed that T cells from HIV-infected individuals express enhanced levels of co-stimulatory ligands upon activation, which provides them with accessory cell properties. Enhanced stimulatory potential of these nonprofessional APC may contribute to persistently high levels of immune activation in HIV infection related to disease progression.