A foetal alpha-1 antitrypsin which resembles PI*I

Summary A transient form of alpha-1 antitrypsin (PI) with an isoelectric point resembling that of the inherited PI*I allele has been detected in ten premature infants up to 35/40 weeks' gestation. It is suggested that this may be a foetal form of alpha-1 antitrypsin which is specially adapted to the uterine evironment.     

Demonstration of shared antigenic determinants between Streptococcus mutans BHT cell membrane, human heart tissue and myosin using monoclonal antibodies to S. mutans

Monoclonal antibodies (MAb) raised to intact Streptococcus mutans P-4 cells (serotype e) were used to demonstrate the presence of shared antigenic determinant(s) between S. mutans BHT (serotype b) cell membranes and human heart tissue. MAb binding to both BHT membrane and human heart tissue was demonstrated by ELISA. Common antigens were identified by immunoblot analysis following separation of BHT membrane components and human heart antigens by SDS-PAGE. MAb 22C4 recognized three polypeptides from the BHT membrane preparation, having molecular masses of 42, 56 and 85 kDa. MAb 22C4 also recognized an 85 kDa component and a 200 kDa component from human heart tissue. MAb D159 was specific for a single 82 kDa polypeptide in BHT membrane, and also bound to two high molecular mass components in human heart (165 and 200 kDa). When both MAb D159 and 22C4 were first absorbed with S. mutans P-4 cells, subsequent reactivity to the aforementioned BHT membrane components was inhibited, indicating that these cross-reactive components are found in S. mutans P-4 as well as in S. mutans BHT micro-organisms. Competitive binding analysis showed that both MAb D159 and MAb 22C4 bound to myosin, indicating that S. mutans BHT membrane, human heart tissue and myosin share at least one immunodeterminant. This indicates that myosin could be the cross-reactive tissue component in human heart.     

Cytotoxic activity ofEscherichia coli O157:H7 culture filtrate on the mouse colon and kidney

Escherichia coli O157:H7 culture filtrate (O157CF) produced colonic and renal lesions in mice following intraperitoneal or intravenous injection. Colonic lesions were characterized by death and sloughing of both surface and crypt epithelial cells, leading to loss of the mucous membrane and subsequent occult colonic hemorrhage. Several areas of severe colonic damage existed where loss of the epithelium and lamina propria was complete, leaving only the submucosal and smooth muscle layers intact. The colon was the only portion of the gastrointestinal tract affected by O157CF. Renal lesions were characterized by marked vacuolation and general necrosis of proximal convoluted tubular cells, and the presence of numerous exfoliated renal epithelial cells in the lumina of distal convoluted and collecting tubules. A neurogenic response was demonstrated by paralysis of the animals' rear extremities. The mouse was a useful model for detecting and studying in vivo the toxic properties of O157CF.     

Serum growth hormone levels and size of pituitary tumour in untreated acromegaly

Serum levels of growth hormone were measured in 84 untreated acromegalic patients. The range of mean level during a glucose tolerance test was 8 to 1,860 ng./ml. and was lognormally distributed. Mean level was reproducible and correlated moderately well with maximum sellar area on lateral tomography. The hormone level was more responsive to oral glucose and insulin-induced hypoglycaemia in patients with smaller tumours. Attention is drawn to limitations of plain radiographs in assessing the size of a pituitary tumour. Suprasellar tumour extensions may be present in patients without visual field defects.     

Evaluation of physical coverings used to control Escherichia coli O157:H7 at the compost heap surface

Throughout four field trials, compost heaps covered with finished compost maintained temperatures under the physical covering that were ca. 7 to 15.5°C higher, resulting in rapid Escherichia coli O157:H7 reduction, than those of the heaps covered with fresh straw or left uncovered. Our results validated recommendations made by the U.S. Environmental Protection Agency for covering fresh compost.     

Reactivation of latent tuberculosis in rhesus macaques by coinfection with simian immunodeficiency virus

Background Tuberculosis (TB) and AIDS together present a devastating public health challenge. Over 3 million deaths every year are attributed to these twin epidemics. Annually, ～11 million people are coinfected with HIV and Mycobacterium tuberculosis (Mtb). AIDS is thought to alter the spontaneous rate of latent TB reactivation. Methodology Macaques are excellent models of both TB and AIDS. Therefore, it is conceivable that they can also be used to model coinfection. Using clinical, pathological, and microbiological data, we addressed whether latent TB infection in rhesus macaques can be reactivated by infection with simian immunodeficiency virus (SIV). Results A low‐dose aerosol infection of rhesus macaques with Mtb caused latent, asymptomatic TB infection. Infection of macaques exhibiting latent TB with a rhesus‐specific strain of SIV significantly reactivated TB. Conclusions Rhesus macaques are excellent model of TB/AIDS coinfection and can be used to study the phenomena of TB latency and reactivation.     

Psychological stress and vitamins

Conditions of stress and anxiety have complex interactions with insufficient vitamin intake and malnutrition. This study, based on literature research in Medline, analyzes the inter-relationship between vitamins and stress. This report concerns a number of vitamins that have been receiving much attention in earlier reviews of the literature, for their potential to protect against stress-related events, and focus is placed upon recent findings.