Partial trisomy 22: A recognizable syndrome

A patient identified as being a partial trisomy 22 mosaic is presented. The presence of a translocation t(4;22) (pter;q12) is noted in the mother, sister and maternal aunt. Comparison is made with nine other reported cases of partial trisomy 22 confirmed by parental translocation. These suggest a definite syndrome, including mental retardation, congenital heart disease, skeletal anomalies, anti-mongoloid slant of the palpebral fissures, preauricular skin tags and low-set ears.     

Antibody Responses to Group A Streptococcal Infections in the Hamster

The immune response after streptococcal infections of the skin and of the joints was studied in an experimental animal model. Hamsters were challenged intradermally or intra-articularly with different streptococcal serotypes, and antibodies for streptolysin O (ASO), deoxyribonuclease B (anti-deoxyribonuclease B), and group A carbohydrate (anti-group A CHO) were determined. After a single injection at either site, 7 of 48 animals (14%) developed group A-CHO antibodies; however, none of the animals developed detectable levels of ASO or anti-deoxyribonuclease B. After repeated infections of the skin or joint, anti-deoxyribonuclease B antibodies were detectable in 13% (4 of 30) and 30% (5 of 17) of the animals, respectively. Elevations of ASO occurred after repeated joint infections in 4 of 16 animals (25%), whereas none of 30 hamsters repeatedly infected intradermally developed antibodies against streptolysin O. For all three antibodies tested, elevated levels were more frequently noted after repeated joint infections than after repeated skin infections with the same streptococcal serotype. These data, similar to ones previously noted in human impetigo, indicate that ASO responses are feeble after streptococcal skin infections and that the site of infection per se, rather than the infecting strain, appears to be responsible for this poor response.     

The effect of 2,4-dinitrophenol and related compounds on bile secretion

1. 2,4-dinitrophenol, 2,4-dinitrophenetole, 2,4-dinitronaphthol, 4,6-dinitro-o-cresol, and to a lesser extent picric acid, produced an increase in bile flow and a rise in body temperature in the anaesthetized dog. The total biliary bromsulphalein (BSP) excretion in unit time was either slightly reduced, increased or remained at its pre-injection level.2. Picramic acid, the nitrochlorophenols and 2,4-dinitrobenzaldehyde caused a moderate increase in bile flow without an effect on the temperature of the animal.3. The three mononitrophenols, the five remaining isomeric dinitrophenols, isopicramic acid, the aminonitrophenols, phenol, 2,4-dinitroanisole, 2,4-dinitrobenzoic acid, 2,4-dinitrobenzene sulphonic acid, 2,4-dinitroresorcinol and 4-nitracatechol had little effect on bile secretion or body temperature.4. It thus appears that, in order for a compound of this type to have a pronounced effect on bile secretion, it is necessary to have nitro groups in positions 2 and 4 of the benzene ring, and a free or potential hydroxyl group.     

Localization of class i histocompatibility molecule assembly by subfractionation of the early secretory pathway

Class I molecules of the major histocompatibility complex bind peptides derived from cytosolic proteins and display them on the cell surface. This function alerts cytotoxic T cells to the presence of intracellular pathogens. Class I molecule assembly requires the association of the heavy chain with β₂-microglobulin, accompanied by peptide loading via specific transporters. This study localizes where these assembly steps take place, using monoclonal antibodies recognizing class I molecules in different assembly states to analyze subcellular fractions of the early secretory pathway. The distribution of peptide-loaded class I molecules was more localized than the distribution of the total pool of class I molecules in the early secretory pathway. Loaded molecules colocalized with the peptide transporter, free heavy chains, and the chaperone calnexin in high density rough endoplasmic reticulum (RER) membranes. These data suggest that subunit assembly and peptide acquisition occur at the same intracellular site. Class I molecules also localized to less dense subfractions of the early secretory pathway, which contained comparatively less peptide-loaded molecules than the high density RER fractions, at steady state. Following a 15 °C temperature block, class I molecules accumulated in these less dense membrane fractions, indicating that these fractions represent the intermediate compartment where empty class I molecules are trapped in mutant cells. In the presence of cycloheximide, a pool of class I molecules recycling to the RER was detected, suggesting empty molecules recycle to acquire peptide.     

Microdissection genotyping of mixed glial and primitive neuroectodermal central nervous system neoplasm

A 22-year-old man with previous radiation treatment for childhood astrocytoma underwent resection of a right parietooccipital lesion. Histopathology revealed a malignant neoplasm with areas of astrocytic and primitive neuroectodermal components. To resolve the relationship and cellular origin, representative tissue was microdissected from several targets, obtaining a balanced mixture of each element. Nonneoplastic brain parenchyma was separately microdissected to determine polymorphic marker informativeness and to serve as an internal negative control. Despite the relatively small quantity of tissue removed for each microdissection target, sufficient material was available for reliable, balanced, polymerase chain reaction-format genotyping encompassing a panel of tumor suppressor genes and genetic loci associated with these forms of neoplasia. The findings revealed distinct discordant genotypic profiles for each of the neoplastic components. The efficacy of the approach used for molecular analysis of this complex neoplasm and the implication of the genotypic findings are discussed.     

An inhibition enzyme-linked immunosorbent assay for the detection of antibody to Rift Valley fever virus in humans, domestic and wild ruminants

This paper describes the development and validation of an inhibition ELISA based on gamma-irradiated tissue culture-derived antigen for the detection of antibody to Rift Valley fever virus (RVFV) in humans, domestic and wild ruminants. Validation data sets derived from field-collected sera in Africa (humans=1367, cattle=649, goats=806, sheep=493, buffalo=258, camels=156) were categorized according to the results of a virus neutralisation test. In addition, individual sera from 93 laboratory workers immunized with inactivated RVF vaccine, 136 serial bleeds from eight sheep experimentally infected with wild-type of RVFV, and 200 serial bleeds from 10 sheep vaccinated with the live-attenuated strain of the virus, were used to study the kinetics of RVFV antibody production under controlled conditions. At cut-off values selected at 95% accuracy level by the two-graph receiver operating characteristic analysis the ELISA sensitivity ranged from 99.47% (humans) to 100% (sheep, buffalo, camels). The specificity ranged from 99.29% (sheep) to 100% (camels). Compared to virus neutralisation and haemagglutination-inhibition tests, the ELISA was more sensitive in detection of the earliest immunological responses in experimentally infected and vaccinated sheep. Our results demonstrate that the ELISA format reported here can be used as a safe, robust and highly accurate diagnostic tool in disease-surveillance and control programmes, import/export veterinary certification, and for monitoring of the immune response in vaccinees.     

Characterization of human papillomavirus infection,P53 and Ki-67 expression in cervix cancer of Mozambican women

In this study, we aimed at evaluating the distribution of HPV types and the expression of P53 and Ki-67 in cervix carcinomas of Mozambican women. Fourty-seven invasive carcinomas, 10 CIN III, and 10 normal cervix were studied. P53 and Ki-67 expression was examined immunohistochemically. HPV infection and HPV types were detected by PCR (GP5+/bio-GP6+) and enzyme-immunoassay, respectively. Expression of P53 and Ki-67 and detection of HPV were as follows: normal cervix--0%, 10%, and 0%, respectively; CIN III--10%, 0%, and 100%, respectively; invasive carcinomas--50%, 55.5%, and 70%, respectively. HPV 16 was identified in 54% of invasive carcinomas, HPV 31, 33, 35, and 45 in 23%, "unidentified" HPV in 19%, and HPV 18 in 4% of invasive carcinomas. No significant associations were observed between P53 expression, Ki-67 expression, and HPV infection. In conclusion, we observed a high frequency of HPV infection in CIN III lesions and invasive carcinomas from Mozambican women, with HPV 16 representing the most frequent viral type. HPV status was not related to P53 and Ki-67 expression. Both P53 and Ki-67 are associated with invasive cervix carcinomas, mainly of the squamous keratinizing histotype.     

Psychiatric disorders associated with risk for the development of eating disorders during adolescence and early adulthood

Longitudinal data were used to investigate whether anxiety, depressive, disruptive, personality, or substance use disorders are associated with risk for the development of eating disorders during adolescence or early adulthood. Psychiatric disorders were assessed among 726 youths from a random community sample during adolescence and early adulthood. Depressive disorders during early adolescence were associated with elevated risk for the onset of eating disorders, dietary restriction, purging behavior, and recurrent weight fluctuations after preexisting eating problems and other psychiatric disorders were controlled statistically. Disruptive and personality disorders were independently associated with elevated risk for specific eating or weight problems. The present findings suggest that depressive disorders during early adolescence may contribute to the development of eating disorders during middle adolescence or early adulthood.