Role of antibodies in T cell-mediated experimental allergic encephalomyelitis

The role of the humoral phase of the immune response in development of T cell-mediated experimental allergic encephalomyelitis (EAE) had not been clearly defined previously even though studies of the myelin basic protein (MBP) molecule had demonstrated the presence not only of T cell but also B cell epitopes capable of inducing cell-mediated immunity and antibody formation. Particularly relevant to this report are the immunological expressions of the region which induces EAE in the Lewis rat. The development of primary demyelination in Lewis rats is preceded by a cell-mediated immune response as well as antibody formation, both of which are highly specific to the encephalitogenic 14-residue peptide that defines the 69-84 region of the parent MBP. Our results are consistent with the dogma that EAE is a T cell-mediated disease, but they also clearly demonstrate an important role for specific antibodies in the development of these T cells responsible for demyelination. The antibody response, which may be heteroclitic, is necessary for T cells to develop into an effector T cell subset. Without this B cell response the subsequent T cell response does not lead to demyelination. In this report we shall discuss these findings and further show that the T cell and B cell epitopes, which are located within the 14-residue sequence, are physically separated and dependent upon the form of synthetic peptides known to induce T cell-mediated and/or humoral immunity.(ABSTRACT TRUNCATED AT 250 WORDS)     

Reduction of acute tubular necrosis (ATN) by furosemide and steroids in cadaveric kidney recovery

One hundred fifty human cadaver kidneys have been preserved by a combination of topical hypothermia and pulsatile perfusion with cryoprecipitated plasma in our laboratory. Post-transplant acute renal failure was reduced from 58 to 21 per cent in those kidneys protected with furosemide and methylprednisolone.     

Polysiloxane: potential noncaloric fat substitute; effects on body composition of obese Zucker rats

Phenylmethylpolysiloxane (PS), a noncaloric, nonabsorbable liquid oil, was studied for effects on body comparison as fat substitute in the diet. Two groups of female obese Zucker rats were fed either a control low-fat (LF) or an experimental diet containing PS (22% wt/wt) incorporated into LF. Two additional groups were fed either PS or cellulose (CE) in diet providing equivalent caloric dilution. Rats on PS lost weight whereas LF control rats gained. Dissectible fat and adipocyte size of PS were smaller than those of LF. Food intake, body water, and adipocyte number did not differ between PS and LF. Body protein on PS increased only in proportion to weight. When both diets were diluted, PS animals lost more weight than CE controls despite similar food intakes, suggesting absorption of calorigenic substances derived from partial digestion of CE but not PS by intestinal microflora. Obese rats did not compensate for caloric dilution with PS.     

Effect of chronic oral nicotine on dopaminergic function in the MPTP-treated mouse

Although epidemiological studies have suggested a lower incidence of Parkinson's disease in cigarette smokers, repeated exposure to cigarette smoke or nicotine does not protect against neurotoxicity induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Since there is some evidence that nicotinic antagonists, nicotine, and neurotransmitters may have tropic effects on neurite outgrowth, the present study examined the effects of chronic nicotine administration for 16 weeks (in drinking water; 5 mg/kg consumed per day) on the rate of terminal recovery after striatal lesioning with MPTP (2 x 30 mg/kg, s.c.). Terminal recovery, as measured by the rate of recovery in the level of striatal dopamine, was not affected by nicotine. Monoamine oxidase-B activity was not reduced by MPTP, nor did nicotine affect its activity in striatal homogenates.     

The relationship between daytime and nighttime food intake in an obese night-eater

Some obese individuals consume food during awakenings from nighttime sleep. Three studies were conducted on a 28-year-old morbidly obese male with chronic sleeping complaints and insignificant weight loss, despite self-reported daily caloric restriction: I. For 3 mo, the subject recorded food intake for 24-h periods. Mean daytime intake was 1286 kcal +/- 386 (SD), and mean nighttime intake was 1036 kcal +/- 487 (SD). Caloric values of daytime and nighttime intake were negatively correlated, r = -0.22, df= 82, p < .05. II. Seven consecutive 24-h food intake recordings were obtained with an automated formula dispenser when the subject was an inpatient on a metabolic ward and received ad libitum formula as his sole food source. Mean daytime intake was 1245 +/- 662 (SD), and mean nighttime intake was 231 +/- 236 (SD). There was a non-significant negative correlation between daytime and nighttime intake, r = -0.32, df = 5, NS. III. The subject underwent polysomnographic studies on 2 non-consecutive nights, following the administration of either a low (600 kcal) or high (1800 kcal) daytime caloric condition. The subject, upon awakening from nighttime sleep, could eat from a platter of sandwich quarters placed at his bedside. The addition of 1200 kcal to daytime intake decreased nighttime intake by 654 kcal, or by 55% of the additional calories delivered during the day. The three studies (I, II, and III) show that daytime food intake can be negatively correlated with nighttime intake, and that daytime intake can influence nighttime intake in a documented obese night-eater.     

MODIFIED BROMOPHENOL BLUE DYE BINDING METHOD FOR QUANTITATION OF MICROALBUMINURIA IN DIABETES MELLITUS

Albumin excretion in microalbuminuria range is one of the earliest manifestation of nephropathy, specially in diabetes mellitus. The modified dye binding method using bromo-phenol blue was studied in 27 healthy controls and 54 patients of diabetes mellitus, negative for albuminuria by albustix test. The analytical recovery (99.4 to 104.0%), within run coefficient of variation (0.8 to 0.36%) and day-to-day coefficient of variation (2.39 to 0.82%), for low and higher range were within acceptable limits. The values in controls ranged as follows: urinary albumin concentration (mg/L) 7.7 – 28.4 in 2-hour specimen and 10.3 – 29.2 in overnight specimen; albumin excretion rate (µg/min) 7.8 – 29.7 in 2-hour and 9.2 – 29.6 in overnight specimen; and albumin creatinine ratio (mg/g) 10.6 – 29.6 in 2-hour and 11.9 – 29.6 in overnight specimens.Correlation analysis of various albumin excretion parameters revealed excellent correlation between estimations from overnight and 2-hour samples for albumin-creatinine ratio (r = 1.00) and albumin excretion rate (r=0.96). Equally good correlation was observed between 2-hour albumin-creatinine ratio and albumin excretion rate (r=0.95). In 10 of 54 patients excretion rate was more than 200 µg/min and could have been detected by repeat albustix test. Of the 36 positive for microalbuminuria, 21 had one or more target organ involvement. There was no target organ involvement in 8 patients negative for microalbuminuria. Screening for microalbuminuria by this simple and economic method, using 2-hour albumin-excretion rate or albumin-creatinine ratio could be one of the earliest investigations in diabetic patients.KEY WORDS: Microalbuminuria, Spectrophotometeric method, Diabetes mellitus     

Animal health emergencies: prevention and preparedness in Asia

Besides response and recovery, prevention and preparedness are the two critical components of any contingency plan. The author discusses the various elements which must be present in the prevention and preparedness plan of countries in Asia. As the continent has such diverse peoples and veterinary infrastructures, the actual plan may vary from one country to another, but must incorporate those elements which are crucial to ensure the success of the preparedness plan.     

Characterization of a panel of neurofilament antibodies recognizing N-terminal epitopes.

Peptides corresponding to sequences from the amino-terminal "head" regions of the low, middle, and high molecular weight neurofilament proteins (NF-L, NF-M, and NF-H) were synthesized by a modification of the Merrifield solid-phase method, and a panel of polyclonal antibodies to these epitopes were prepared in rabbits by the injection of synthetic peptides conjugated to the carrier protein keyhole limpet hemocyanin (KLH). An additional, monoclonal antibody recognizing both glial fibrillary acidic protein (GFAP) and vimentin was also produced, by fusion of cells of the mouse myeloma line NS-1 with spleen cells from a mouse immunized with cytoskeletal extracts. Antibody specificities were confirmed by a combination of Western blotting against cytoskeletal extracts and immunofluorescence using both rat brain sections and fibroblasts transfected with fully encoding cDNAs for each neurofilament protein, driven by viral promoters.