Regional vascular responses to asphyxia in the rabbit

Organ blood flow was measured in eight spontaneously breathing male New Zealand white rabbits exposed to a 50 min period of asphyxia. The results were compared with eight control animals. Cardiac output and arterial pressure did not change. There was increased flow to the heart, brain and diaphragm. Flow to the kidneys and adipose tissue was reduced. Flow to the gastro-intestinal tract, liver, skeletal muscle and carcass was unchanged. Prolonged moderate asphyxia produces preferential blood supply to vital organs and maintains flow to the skeletal musculature and the gastro-intestinal tract; their blood supply is diverted mainly from the kidneys. These changes are similar to those seen in haemorrhagic and endotoxic shock in the rabbit.     

CHANGES OF G-PROTEIN LEVELS IN PLATELET MEMBRANES FROM ALCOHOLICS DURING SHORT-TERM AND LONG-TERM ABSTINENCE

The levels of G     

G<Subscript>i2</Subscript>α protein deficiency: A model for inflammatory bowel disease

Mice deficient for the G protein subunit G_i2α were obtained by gene targeting. They displayed a growth retardation that was apparent at 6 weeks of age. They subsequently developed diffuse colitis with clinical and histopathological features closely resembling those of ulcerative colitis in humans. Seven of 20 G_i2α-deficient mice with colitis also developed adenocarcinomas of the colon. G_i2α-deficient thymocytes displayed two-to fourfold increases in mature CD4⁺8^? and CD4^?8⁺ phenotypes, an approximately threefold increase in highintensity CD3 staining and enhanced proliferative responses to T-cell receptor stimuli. Stimulation of G_i2α-deficient peripheral T cells induced a hyperresponsive profile of interleukin-2, tumor necrosis factor, and interferon-γ production, which may reflect a heightened response of primed cells or a defective negative regulation. We suggest that G_i2α-deficient mice may represent a useful animal model for dissecting the pathomechanisms of inflammatory bowel disease and also for the development of novel therapeutic strategies.     

Applications of BOP reagent in solid phase synthesis Advantages of BOP reagent for difficult couplings exemplified by a synthesis of [Ala 15]-GRF(1–29)-NH2

The BOP reagent [benzotriazol-l-yl-oxy-tris-(dimethylamino)phosphonium hexafluorophosphate] introduced by Castro et al. [Tetrahedron Lett. (1975) 14, 1219–1222] is ideally suited for solid phase peptide synthesis. The rate of coupling using BOP compared favorably to DCC and other methods of activation including the symmetrical anhydride and DCC/HOBt procedures. BOP couplings using the solid phase procedure proceeded more rapidly and to a greater degree of completion for peptide bond formations that were previously determined to be very slow using the conventional DCC method. Stepwise solid phase peptide synthesis using BOP was successfully utilized for the preparation of the (22–29) and (13–29) fragments of [Ala¹⁵]-GRF(1–29)-NH₂. Single couplings with 3 equiv. BOP and Boc-amino acids and 5.3 equiv. of diisopropylethylamine in DMF were used for each cycle. The yields of the fragments were superior and the purities comparable using the BOP procedure (single couplings) to those observed using multiple couplings via the DCC coupling method. A total synthesis of [Ala¹⁵]-GRF(1–29)-NH₂ was also carried out using the BOP procedure (single couplings and 3 equiv. BOP and Boc-amino acids and 5.3 equiv. diisopropylethylamine in DMF for each cycle). Multiple couplings were only required for Boc-Asn-OH due to the proposed formation of Boc-aminosuccinimide during activation. The resultant GRF(1–29) analog was comparable to a control prepared with multiple DCC couplings under optimized conditions. In a parallel study, unprotected Boc-(hydroxy)-amino acids were successfully coupled with the BOP reagent. However, the number of coupling cycles after the introduction of unprotected hydroxy-amino acid must be minimal (<10). The use of the BOP reagent with unprotected Tyr in solid phase peptide synthesis was also clearly established.     

CO-MORBIDITY BETWEEN DERMATOLOGIC DISEASES AND PSYCHIATRIC DISORDERS IN PAPUA NEW GUINEA

Background. Neurodermatitis (now subdivided into lichen simplex chronicus and atopic dermatitis) was included among the psychosomatic disorders. Psychologic causes have been suggested for many skin conditions, such as urticaria, lichen simplex chronicus, atopic dermatitis, psoriasis, alopecia areata, and pruritus. The evidence for psychologic causation is neither strong nor convincing; however, psychiatric disorders are common among people with established skin diseases. Recent investigators have published data reporting co-morbidity between certain psychiatric disorders and skin diseases. The objective of the research was a prospective clinical study of 132 consecutive patients, who attended the dermatologic outpatient clinic of the Port Moresby General Hospital during 1992. Methods. The instrument for the study is the Harding Self-Rating Questionnaire (sro ) that has been demonstrated to work well as a gross screening instrument in the Urban Primary Health Care Clinic setting. The questionnaire was administered to 132 outpatients by one of the investigators (hm ). Those patients who scored above the cut-off point of seven were referred to the second investigator (fyaj ) for examination of their mental state. Results. The results of the study showed all 132 patients were adults, aged between 16 and 75 years. There were 67/132 (50.75%) men and 65/132 (49.24%) women patients. The psychiatric diagnoses for the women patients were: normal variation 17/65, anxiety neurosis 11/65, and neurotic depression 37/65. For the men patients, the psychiatric diagnoses were: normal variation 21/67, anxiety neurosis 15/67, and neurotic depression 30/67. One man with psoriasis also presented with clinical features of schizophrenic psychosis. Conclusions. The results of the study support the hypothesis, that there is a co-morbidity between some psychiatric disorders and some skin diseases.