Nuclear magnetic resonance studies on bacterial copolyesters of 3-hydroxybutyric acid and 3-hydroxyvaleric acid

Copolyesters of 3-hydroxybutyric acid (HB) and 3-hydroxyvaleric acid (HV), P(HB-co-HV), were isolated from Alcaligenes eutrophus and characterized by solution NMR, solid-state ¹³C CP/MAS NMR, and differential scanning calorimetry. The ¹³C CP/MAS NMR analysis was compatible with that of a random copolyester of oxy-(1-methyl-3-oxotrimethylene) ( B ) and oxy-(1-ethyl-3-oxotrimethylene) ( V ) units which adopts a regular conformation of a 2₁ -helix in the solid state throughout a wide range of compositions varying from 0 to 90 mol-% V units. The chain dynamics of P(HB-co-HV) in chloroform was studied by analysis of the ¹³C and ¹H NMR spectra. The carbon-13 spin-lattice relaxation times (T₁) and nuclear Overhauser enhancements (NOE) indicated that the copolyester molecules in chloroform are not rigid but rather flexible. The conformational preferences of the copolyester molecules were determined by analysis of the ¹H NMR spectra.     

QT interval and QT dispersion in eating disorders

BACKGROUND: Eating disorders are thought to be risk factors for cardiac sudden death secondary to arrhythmia. Results in previous studies on QT interval and QT dispersion, markers of fatal arrhythmia, have been inconsistent. METHODS: We prospectively examined 179 female eating disorder patients, being over 18 years old and diagnosed according to the DSM-IV criteria between January 1995 and December 2002, and 52 healthy women. Patients with abnormal plasma electrolytes or taking medications that might influence the electrocardiogram (ECG) were excluded from the study. QT intervals were corrected for heart rate using Bazett's formula and the nomogram method, which is more reliable at extremely low heart rates than Bazett's formula. QT dispersion was measured as the difference between the longest and shortest QT intervals. QT intervals and QT dispersion in each patient group were compared with those in the control group. RESULTS: The 164 eligible patients consisted of 43 patients with anorexia nervosa restricting type, 35 with anorexia nervosa binge eating/purging type, 63 with bulimia nervosa purging type, and 23 with bulimia nervosa non-purging type. There was no significant difference in age between eating disorder patients and controls. QT interval and QT dispersion were significantly longer in all eating disorder subtypes than in the control group. QT interval and QT dispersion were significantly correlated with the rate of body weight loss in bulimia nervosa. CONCLUSIONS: QT interval and QT dispersion were prolonged in both anorexia nervosa and bulimia nervosa. Examination of ECG in eating disorder patients without extremely low body weight also appears to be clinically important.     

"True" posterior communicating artery aneurysm presenting the abducens nerve palsy

Most of "so-called" posterior communicating artery aneurysms previously reported, originated from the internal carotid-posterior communicating junction. Aneurysms arising from the posterior communicating artery itself are very rare. The abducens nerve palsy caused by cerebral aneurysm is also very rare. We are reporting a case with the saccular aneurysm arising directly from the distal half of the posterior communicating artery presenting the abducens nerve palsy. This 73-year-old woman who had no treatment with hypertension for several years was admitted for sudden onset of severe headache, vomitting and unconsciousness on March 1, 1984. She opened her eyes when addressed and had disorientation, urinary incontinence, right-hemiparesis and left-abducens nerve palsy. A 4-vessel angiography revealed the saccular aneurysm originating directly from the distal half of the posterior communicating artery. The patient underwent left-frontotemporal craniotomy on the 27th day after subarachnoid hemorrhage under Hunt & Kosnic Grade 3. The aneurysm originated directly from the distal half of the posterior communicating artery and directed inferior-posterior-laterally below the oculomotor nerve. The neck was successfully clipped. Immediate post-operative course was uneventful until the 7th day after surgery. On the 8th day she had hypertensive intraventricular hemorrhage and expired. The autopsy could not be obtained. The saccular "true" posterior communicating artery aneurysm with isolated unilateral abducens nerve palsy as seen in our case has not been reported. Considering the operative findings, we thought the aneurysmal dome contacted directly with the abducens nerve.     

31P and23Na nuclear magnetic resonance study on forebrain ischemia in rats with shift reagent Dy(TTHA)

³¹P and ²³Na nuclear magnetic resonance (NMR) spectroscopy was employed to study the dynamic changes in intracellular high-energy phosphates and sodium during 15min of forebrain ischemia and recirculation in in vivo rat brain. In the presence of the shift reagent Dysprosium triethylenetetramine-N,N,N,N,N,N-hexaacetic and [Dy(TTHA)], the sodium peak separated into two peaks, unshifted and shifted. During 15min of ischemia, the unshifted sodium peak decreased and the shifted sodium peak increased. With recirculation, the unshifted and the shifted sodium peaks returned to the preischemia level within 10min, but the shifted one increased during 30–60min. Intracellular high-energy phosphates and intracellular pH (pHi) decreased during 15min of ischemia and returned to the preischemia levels within 20min of recirculation. We conclude that the decrease in unshifted sodium peak during ischemia is due to the decrease in subarachnoid sodium and the cellular influx of interstitial sodium would be minimum. The increase in shifted sodium peak during ischemia is considered to be due to the dilatation of cerebral blood vessels and the increase in interstitial sodium which was transported from subarachnoid space.(Kurata M: ³¹P and ²³Na nuclear magnetic resonance study on forebrain ischemia in rats with shift reagent Dy(TTHA). J Anesth 7: 325–333, 1993)     

Immunohistochemical dynamics of leukotoxin (9.10-eooxv-12-octadecenoic acid) in lungs of rats

This paper investigates the immunohistochemical dynamics of leukotoxin (9,10-epoxy-12-octadecenoic acid, LTx) in the lungs of rats exposed to hyperoxia with or without paraquat. The rats were treated with 100% oxygen or ambient air for 24. 48, 72 and 96 h in the presence or absence of a low or high dose paraquat (1,1-di-methyl-4,4-bipyridinium, PQ) injection. Immunostaining for LTx demonstrated positive reactions in the neutrophils that showed a progressive increase in intensity of staining with time in all groups exposed to 100% oxygen and in the group with high dose PQ, but the positive findings were weak in the group injected with low dose PQ only. We found the positive immunostaining reaction not only in neutrophils but also in alveolar macrophages. This indicates that LTx is produced by alveolar macrophages as well as by neutrophils depending on the treatment period under hyperoxic conditions, suggesting that LTx is an important chemical mediator in pulmonary diseases.     

A study on how a 6-month aerobic exercise program can modify coronary risk factors depending on their severity in middle-aged sedentary women

It is well known that physical exercise can reduce coronary risk factors. But how an aerobic exercise modifies coronary risk factors in relation to severity and physical fitness is still controversial. Fifty-four middle-aged women (mean age, 55 years) completed a 6-month on-site and home-based anaerobic threshold-level exercise program. The changes in coronary risk factor profiles were observed during the pre-intervention and intervention periods. Before the intervention (during control period), most coronary risk factors showed a rather unfavorable trend. After the program, their mean body weight decreased from 56.7 to 55.7 kg (p>0.05) and the proportion of body fat from 30.9 to 27.9% (p>0.05) without any reduction in lean body mass. Systolic blood pressure (SBP) decreased from 129.0 to 125.0 mm Hg (p>0.05) and diastolic blood pressure from 79.5 to 76.6 mm Hg (p>0.05). Fasting plasma glucose (FPG) declined from 109.6 to 103.4 mg/dl (p>0.05). Changes in SBP and FPG were most remarkable in their respective worst tertile. Serum lipids improved only modestly. Maximum oxygen uptake increased from 23.6 to 26.1 ml/kg/min (p>0.01). However, no significant correlations were found between changes in coronary risk factors and those in physical fitness. We conclude that the 6-month aerobic exercise program would modify women’s coronary risk factors depending on their initial values, probably independently of the changes in physical fitness.     

Completely covered cloacal exstrophy: recognition of a new clinical sub-entity

A case showing many of the typical visceral features of cloacal exstrophy is reported. The patient had fn imperforate anus, a cecal-cloacal fistula, dehiscence of the pubiic symphysis, and lumbosacral spina bifida with synsingomyelia, but the lower abdominal wall was intact without any visceral extroversion. The pertinent literature was reviewed, and it was found that this case corresponded to t typical case of completely covered cloacal exstrophy. Only six cases, including the present one, have so far been reported in the literature. From a clinical viewpoint, it apparently occupies an intermediate position in the wide spectrum of cloacal anomalies between classical cloacal exstrophy and imperforate anus with recto-cloacal fistula, but anatomatically and embryologically it is definitely a variant of cloacal exstrophy. In other words, it looks like an imperforate anus with recto-cloacal exstrophy, but should be treated as a variant of loacal exstrophy. The anatomy, classification, embryology, diagnosis, and management of this peculiar surgical condition are discussed, and recognition of this entity is urged.