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Inflammation of the temporomandibular joint (TMJ) can alter behavioral responses such as food intake and mobilize stress hormones. The hypothesis of this study was that food intake and diurnal corticosterone analysis can be used as indicators of adjuvant-induced TMJ inflammation. Groups of rats received adjuvant or no injections at the beginning of the resting (AM) or activity (PM) phase. Forty-eight hours (early) or 6 weeks (late) after adjuvant injection, plasma corticosterone was assayed and food intake was recorded. Food intake was suppressed up to 4 days post-injection. As expected, the non-injected group showed low AM and high PM corticosterone. AM corticosterone was elevated, but PM corticosterone was attenuated in both early- and late-stage-injected rats. A computerized pair-fed experiment showed that adjuvant-induced hypophagia did not alter corticosterone levels. Meal pattern analysis revealed decreased food intake due to a decrease in the number of meals taken. Notably, meal size remained the same but meal duration increased. This model demonstrated that food intake and stress hormone analysis could be used as indicators for sequelae of adjuvant-induced TMJ inflammation.

The hospital records of 58 patients operated on for tuberculous perforations of the small intestines at our hospital between 1987 and 1996 were reviewed. Clinical features were non-specific in the majority of the patients. Pneumoperitoneum on abdominal radiographs was present in only 28 (48.3%) patients. Forty-five (77.6%) were operated on within 36 hours of perforation. Surgical management consisted of resection and end-to-end anastomosis (n = 45); oval excision of the perforation and transverse anastomosis reinforced with an omental patch (n = 7); ileo-transverse colostomy (n = 5); and peritoneal drainage only (n = 1). There were 17 deaths (29.3%). Adverse prognostic factors were operation beyond 36 hours (p0.01), multiple perforations (p0.001), and faecal fistula formation (p0.01). Mortality was least with early resection and end-to-end anastomosis of the perforated bowel segment. We conclude that a high index of suspicion is essential for early diagnosis and optimal treatment of patients with tuberculous intestinal perforations.

The three-dimensional structures of rabbit and human liver cytosolic serine hydroxymethyltransferase revealed that H231 interacts with the O3' of pyridoxal-5'-phosphate and other residues at the active site such as S203, K257, H357 and R402 (numbering as per the human enzyme). This and the conserved nature of H231 in all serine hydroxymethyltransferases highlights its importance in catalysis and/or maintenance of oligomeric structure of the enzyme. In an attempt to decipher the role of H230 (H231 of the human enzyme) in the catalytic mechanism and/or maintenance of oligomeric structure of sheep liver serine hydroxymethyltransferase, the residue was mutated to arginine, phenylalanine, alanine, asparagine or tyrosine. Our results suggest that the nature of the amino acid substitution has a marked effect on the catalytic activity of the enzyme. H230R and H230F mutant proteins were completely inactive, dimeric and did not bind pyridoxal-5'-phosphate. On the other hand, mutation to alanine and asparagine retained the oligomeric structure and ability to bind pyridoxal-5'-phosphate. These mutants had only 2-3% catalytic activity. The side reactions like transamination and 5,6,7, 8-tetrahydrofolate independent aldol cleavage were much more severely affected. They were able to form the external aldimine with glycine and serine but the quinonoid intermediate was not observed upon the addition of 5,6,7,8-tetrahydrofolate. Mutation to tyrosine did not affect the oligomeric structure and pyridoxal-5'-phosphate binding. The H230Y enzyme was 10% active and showed a correspondingly lower amount of quinonoid intermediate. The kcat / Km values for L-serine and Lallothreonine were 10-fold and 174-fold less for this mutant enzyme compared to the wild-type protein. These results suggest that H230 is involved in the step prior to the formation of the quinonoid intermediate, possibly in orienting the pyridine ring of the cofactor, in order to facilitate effective proton abstraction.

The 12C(12C,n) reaction (Q=-2.6 MeV) is a potential neutron source for the weak s-process occurring in shell-carbon burning of massive stars. The uncertainty in this reaction rate limits our understanding of the production of elements in the range 60 < A < 110. Current stellar models must rely on the smooth extrapolation of a dubious statistical model calculation based on experimental data taken at energies well above the Gamow window which lies below 3.2 MeV. At Notre Dame, this reaction cross section has been measured in finer steps at energies above 3.5 MeV, while successful measurements down to 3.1 MeV have just recently been achieved. In addition, a new extrapolation based on measurements of the mirror system has been developed which predicts a number of low-energy resonances while accounting well for the high-energy resonances. An overview of this work along with the most recent results and astrophysical implications are presented.

The 12C+12C fusion reaction plays a crucial role during stellar evolution. The astrophysically important energy range spans from 1 MeV to 3 MeV. However, its cross section has not been determined with enough precision, despite numerous studies, due to the extremely low reaction cross sections and the large experimental background. To allow measurements of the 12C+12C fusion at astrophysical energies, we developed an efficient thick-target method using large-area silicon strip detectors. Further measurements at even lower energies will be performed using coincidences between a silicon-detector and a Ge-detector array, at the high-current accelerator under construction at the University of Notre Dame. Since the coincidence method does not allow obtaining information about the channels without gamma-ray emission, a solenoid spectrometer has been constructed for complementary measurements. Meanwhile, we are also investigating the 24Mg(α, α') reaction using the Grand Raiden Spectrometer at RCNP to search for potential resonances in the 12C+12C fusion reaction. Preliminary results from these measurements will be presented.

The elements between iron and strontium are largely produced by the weak s-process occurring in massive stars during the late stages of convective core He burning and the convective shell carbon burning with the primary source of neutrons coming from the reaction 22Ne(α,n)25Mg. However, shell carbon burning may produce hot enough temperatures to activate 12C(12C,n)23Mg as a significant neutron source. Few studies have been done on this reaction, and the extrapolation from experimental data down to the relevant astrophysical energies is uncertain. Recent studies performed at the Nuclear Science Laboratory of Notre Dame aim to improve the existing reaction data using new experimental techniques as well as provide a more reliable extrapolation to the low energies not accessible by experiment. Preliminary results will be presented and the astrophysical implications will be discussed.

Summary Cold injury was produced by immersing the rabbits' hind limbs in a mixture of ice and alcohol at a temperature of −5°C. to −10°C. for 2 hours. The limb was thawed slowly at the room temperature. Extent of damage was classified into six degrees, depending upon tissue survival. The efficacy of nicotinic acid, 10 to 20 mg. per kilogram of body weight, administered orally in three divided doses, was studied in different groups of rabbits. Nicotinic acid proved useful in reducing or preventing the damage caused by local cold injury in rabbits. Some possible explanations for this beneficial effect are discussed.

Various therapeutic measures and drugs have been used in minimizing the deleterious effects of cold injury. Considering the cold injury as an aseptic inflammatory process,1 we decided to evaluate the possible role of the anti inflammatory agent, oxyphenbutazone (Tanderil), in the treatment of cold injury in rabbits.

An evaluation of the Federal Weatherization Assistance Program to determine the fuel savings for participants in Minnesota has been completed. The homes selected in this study were weatherized between April and October 1978. Therefore, a comparison of normalized fuel consumption for the 1976 to 1977 and 1977 to 1978 heating seasons was an appropriate measure of the fuel savings achieved. In addition, a control group was established to reflect fuel consumption changes resulting from the effect of other public energy awareness programs. The results indicate that the average energy savings was 13.43%. This was based on 59 sample group and 37 control group homes representing the population of all weatherized and non-weatherized low-income homes in the state, respectively. The conclusions of this study are: at an average fuel cost of $6 per million Btu, weatherization has been accomplished at a simple payback of 3.5 years; 90% of the weatherized homeowners have expressed varying degrees of positive satisfaction; behavioral changes (example, raising thermostats) are significant in offsetting potential weatherization savings; and the Retrotech Job Book, in its present form, has not been used effectively.

A new method has been devised to assess the competence of the canine aortic valves, before implantation. This method would provide a better selection of aortic valves before their insertion and may reduce the incidence of postoperative incompetency. Comparison of canine pulmonary and aortic valve function, at various pressures, revealed that the pulmonary valves were regurgitant at higher pressures, in comparison to aortic valves. Formalin preserved valves were found to be significantly regurgitant.

Hearts from 131 unselected medicolegal autopsies have been studied. The age of the subjects ranged from 5 to 80 years old. After the coronary arteries were injected with radio opaque dye in gelatin the hearts were dissected and angiograms taken. Depending upon the pattern of coronary artery circulation, the hearts, were categorised into 3 groups. Group I or right preponderant heart was found in 63% of cases, group II or heart with 'balanced circulation' was present in 25% of cases while group III or 'left preponderant' heart was seen in 12% of the cases. This pattern of circulation is similar to that observed in the western population. Coronary collateral circulation was seen in all hearts, of all age groups. However, mild degree of anastomoses were common in the first three decades of life while in the later decades anastomoses were often marked. Hearts with grade III and IV coronary occlusions showed moderate to marked anastomoses in 70% of the cases. Myocardial scars were seen in 24 hearts. Of these, 22 had grade III and IV occlusions in their coronary arteries while, only 2 hearts had grade II occlusive lesions. The anastomoses were moderate to marked in 67% of these hearts.

ACUTE mountain sickness and high altitude pulmonary oedema are two acute medical problems for troops in the Himalayan terrain who frequently shuttle between sea level and high altitudes (10,000–16,000 ft.). These two acute illnesses have some features in common: time lag (they rarely occur within 12 h of arrival at the altitude or 96 h after arrival), throbbing headache, muscular cramps and pulmonary congestion. We have studied the acute circulatory response to high altitude hypoxia and investigated the extent to which shifts in the circulating blood volumes, if any, could be related to the time lag and clinical features of these acute illnesses.

Postoperative peritoneal adhesions are one of the important causes of intestinal obstruction. Coletti and Bossart 1 reported that in their series, intestinal adhesions were responsible for 90% of small bowel obstructions in the early postoperative period. Numerous agents have been studied experimentally and clinically with regard to their usefulness in preventing the formation of intraperitoneal adhesions, but none, as yet, has proved consistently useful. Considering formation of peritoneal adhesions as an inflammatory process, 2 an anti-inflammatory agent, oxyphenbutazone, has been used in this study to prevent it. Materials and Methods Forty rabbits were anesthetized with intravenously administered pentobarbital sodium. A laparotomy was carried out by a midline incision. The cecum and corresponding parietal peritoneum were scraped until the normal gloss was lost. The abdomen was closed in layers. The animals were studied in the following groups: Group A. —This group was subdivided into two. Group Al, the control group, consisted

Peritoneal adhesions were produced in 20 rabbits and 35 monkeys by traumatizing the cecum and corresponding parietal peritoneum. Adhesions were classified into six grades, depending on the extent and density. Combined therapy with oxyphenbutazone, proteolytic enzymes from carica papaya, and dextran 40 after lysis of adhesions reduced the reformation of peritoneal adhesions significantly, and the percentage reduction was greatest as compared to the individual use of the drugs. It is emphasized that the role of any therapy in peritoneal adhesions should be evaluated only by the decrease in the reformation of adhesions after lysis.