Influence of carrier-specific, thymus-derived cells on the immunologlobulin M antibody response to staphylococcal lipoteichoic acid

The immunoglobulin M antibody response to the lipoteichoic acid (LTA) of Staphylococcus aureus ATCC 6538P was examined by a procedure in which erythrocytes sensitized with periodate-activated LTA were used for the detection of immunoglobulin M-producing plaque-forming cells LTA-specific plaque-forming cells were first detected 2 days after immunization with heat-killed bacterial cells, and maximal numbers of plaque-forming cells, mostly of the immunoglobulin M class rather than the immunoblogulin G or immunoglobulin A class, were attained by day 4; specificity for LTA was affirmed by plaque inhibition tests. No plaque-forming cells were found in mice given isolated LTA over a 10,000-fold range of immunizing doses. Mice pretreated with a carrier known to activate thymus-derived helper lymphocytes produced a plaque-forming cell response to LTA only when immunized with LTA bound to the same carrier. This suggests that carrier-specific thymus-derived cells are needed to initiate an antibody response to poorly immunogenic LTA. Since an antibody response can be elicited in mice given heat-killed cells, other cell wall and/or cell membrane constituents may play an important role as immunologically active carriers for this antigen.     

General anaesthesia for surgery can influence circulating melatonin during daylight hours

BACKGROUND: Both melatonin and anaesthetics have been shown to affect sleep and behaviour. The effect of general anaesthesia on circulatory melatonin has not been reported, but anaesthetic-related alterations in hormone profiles are known. We hypothesize that differences in recovery from anaesthesia may be associated with differences in circulatory melatonin levels because of melatonin's sedative effect in humans. METHODS: The influences of general anaesthesia and surgery on circulating melatonin, prolactin, and cortisol concentration were investigated in 32 female patients scheduled for elective gynaecological surgery to study differences in hormone profiles and responses during anaesthesia and the recovery period. Patients were randomly assigned to one of two groups. General anaesthesia was induced with either thiopentone/fentanyl (Group 1: n = 16) or propofol/fentanyl (Group 2: n = 16). Maintenance of anaesthesia was achieved with either isoflurane (0.8-1.0 vol%)/fentanyl (Group 1) or propofol (6 mg.kg-1.h-1)/fentanyl (Group 2) with a N2O/O2 flow ratio of 2:1 in both groups. During anaesthesia, patients' eyes were carefully taped shut to prevent light effects. Blood samples were taken before and after premedication, immediately before induction of anaesthesia, every 15 min during anaesthesia, and hourly in the recovery room for 8 h. The control group consisted of 6 healthy women who were not subjected to surgery, but who were in a similar environment, including light conditions, as the study groups. RESULTS: Isoflurane and propofol anaesthesia as well as darkness elicited elevated plasma melatonin levels that persisted in the recovery period in patients anaesthetized with isoflurane, but gradually decreased during the recovery of patients anaesthetized with propofol. Circulating prolactin and cortisol values were also elevated during anaesthesia and had similar decreases during the recovery period. CONCLUSION: Higher plasma levels of melatonin during the recovery period following isoflurane anaesthesia may, in part, explain increased sedation in these patients compared with patients who received propofol anaesthesia. However, the relationship between recovery from anaesthesia and plasma melatonin levels may not be simple and straightforward.     

The resistance of cowpea seeds to bruchid beetles is not related to levels of cysteine proteinase inhibitors

A cDNA encoding a cysteine proteinase inhibitor was isolated from a cDNA library prepared from developing seeds of an insect-resistant line of cowpea. The sequence of the encoded protein was homologous with those of other plant cysteine endoproteinase inhibitors, and with Type 2 cystatins from animals. Southern blot analyses indicated that small gene families were present in both resistant and susceptible lines of cowpea, while northern blot analyses showed similar levels of expression. It is concluded that the levels of expression of the inhibitor do not account for the differences in insect resistance of the two lines.     

The Academy of Psychosomatic Medicine practice guidelines for psychiatric consultation in the general medical setting. The Academy of Psychosomatic Medicine

This practice guideline seeks to provide guidance to psychiatrists who regularly evaluate and manage patients with medical illnesses. The guideline is intended to delineate the knowledge base, professional expertise, and integrated clinical approach necessary to effectively manage this complex and diverse patient population. This guideline was drafted by a work group consisting of psychiatrists with clinical and research expertise in the field, who undertook a comprehensive review of the literature. The guideline was reviewed by the executive council of the Academy of Psychosomatic Medicine and revised prior to final approval. Some of the topics discussed include qualifications of C-L consultants, patient assessment, psychiatric interventions (e.g., psychotherapy, pharmacotherapy), medicolegal issues, and child and adolescent consultations.