Effect of Glycemic Carbohydrates on Short-term Satiety and Food Intake

We examine the relationships between glycemic carbohydrate and its effects on short-term satiety and food intake. Both high- and low-glycemic carbohydrates have an impact on satiety, but their effects have different time courses. High-glycemic carbohydrates are associated with a reduction in appetite and food intake in the short term (e.g., one hour), whereas the satiating effects of lower-glycemic carbohydrates appear to be delayed (e.g., 2 to 3 hours). There is no consistent evidence that an increase in blood glucose, either acute or sustained, is the primary determinant of their effects on food intake and satiety. Many other preabsorptive and postabsorptive signals for satiety exist and may be the determining factors. Further studies are needed to delineate the role of glycemic carbohydrates and their mechanisms of action in determining satiety.     

Efficacy of short‐term oral cobalamin therapy for the treatment of cobalamin deficiencies related to food‐cobalamin malabsorption: A study of 30 patients

Background: It has been suggested that oral cobalamin (vitamin B₁₂) therapy may be an effective therapy for treating cobalamin deficiencies related to food‐cobalamin malabsorption. However, the duration of this treatment was not determined. Patients and method: In an open‐label, nonplacebo study, we studied 30 patients with established cobalamin deficiency related to food‐cobalamin malabsorption, who received between 250 and 1000 μg of oral crystalline cyanocobalamin per day for at least 1 month. Endpoints: Blood counts, serum cobalamin and homocysteine levels were determined at baseline and during the first month of treatment. Results: During the first month of treatment, 87% of the patients normalized their serum cobalamin levels; 100% increased their serum cobalamin levels (mean increase, +167 pg/dl; P < 0.001 compared with baseline); 100% had evidence of medullary regeneration; 100% corrected their initial macrocytosis; and 54% corrected their anemia. All patients had increased hemoglobin levels (mean increase, +0.6 g/dl) and reticulocyte counts (mean increase, +35 × 10⁶/l) and decreased erythrocyte cell volume (mean decrease, 3 fl; all P < 0.05). Conclusion: Our findings suggest that crystalline cyanocobalamin, 250–1000 μg /day, given orally for 1 month, may be an effective treatment for cobalamin deficiencies not related to pernicious anemia.     

Klinefelter's Syndrome: Hypogonadism,abnormal carbohydrate metabolism. Is it a result of biotin deficiency?

The aetiology of Klinefelter's Syndrome is not known. The causative factor(s) must explain the hypogonadism, low androgen levels, the disordered carbohydrate metabolism and the commonly associated psychiatric conditions. A biotin deficient/dependent state can account for the above. A biotin deficient Klinefelter's Syndrome patients with the above is described. The possible role of biotin in the primary, secondary and tertiary prevention of Klinefelter's Syndrome needs further research.     

Glycemic Carbohydrate: An International Perspective

Attention to the different types of carbohydrates and their role in health and disease is relatively recent. FAO and WHO jointly published a report on carbohydrates in human nutrition in 1998, with a number of recommendations about increasing carbohydrate intake as a sound approach to the prevention of obesity. The glycemic index (GI) was recommended as a means of classifying foods on the basis of their potential for raising blood glucose; this concept was based on the understanding that the state of hyperglycemia that is observed following the intake of certain high-GI carbohydrate foods could constitute a risk factor for diseases of lifestyle.     

Prediction of lactose malabsorption in referral patients

Two hundred forty-two patients referred for various gastrointestinal complaints were evaluated for clinical parameters that would predict findings of lactose malabsorption. Breath hydrogen and blood glucose lactose tests were performed after ingestion of 50 g lactose. Presenting complaints, duration of symptoms, and patient demographics such as age, sex, and ethnic heritage were not different between lactose malabsorbers and absorbers as defined by the breath hydrogen lactose test. Foodrelated symptoms in general and after specific foods such as milk, ice cream, cheese, and yogurt were also similar between groups. Prior to testing, 30% of malabsorbers (N=161) and 36% of absorbers (N=81) reported lactoserelated symptoms (P=NS). The blood glucose response to lactose was abnormal in 60% of malabsorbers and 15% of absorbers. This study confirmed our impression that it is difficult to predict lactose absorption status by clinical parameters. The majority of our lactose malabsorber patients were unaware of lactose-associated symptoms. Furthermore, symptom assessment, demographics, food history, and blood glucose testing did not predict abnormal hydrogen responses to lactose.The opinions and assertations expressed herein are those of the authors and are not to be construed as reflecting opinions of the United States Air Force or the Department of Defense.This work has been presented in part at the Annual Scientific Session of the American Gastroenterological Association, San Francisco, California, May 19, 1986, and published as an abstract (Gastroenterology 90:1562, 1986).     

Monoclonal antibodies (2C5 and 4C9) against lactoseries carbohydrates identify subsets of olfactory and vomeronasal receptor cells and their axons in the rabbit

Monoclonal antibodies (MAbs) against lactoseries carbohydrates were used to study immunohistochemically the olfactory and vomeronasal receptor cells and their axons in the rabbit. MAb 2C5, which recognizes Gal alpha 1----3Gal beta 1----4G1cNAc----R structure, selectively labeled a subset of olfactory receptor cells and the majority of vomeronasal receptor cells. MAb 4C9, which reacts with fucosyl poly-N-acetyllactosamine, identified a subset of vomeronasal receptor cells. The above two MAbs also labeled the axons of these chemosensory receptor cells and thus revealed their axonal projection sites in the main and accessory olfactory bulbs.     

Role of dietary fat in calorie intake and weight gain

This paper reviews the literature on the role of dietary fat in calorie intake and body weight gain in humans and laboratory animals. An overview of 40 animal studies which compared growth on high-fat (HF) and high-carbohydrate (HC) solid/powdered diets indicated that the HF diet elicited greater weight gain in 33 out of 40 studies. Enhanced growth on the HF diet was often, but not exclusively, attributable to greater caloric intake. Additional evidence for the growth-enhancing effect of HF diets emerges from "diet option" and "supermarket" feeding studies in rats, and experimental and epidemiological studies in humans. Three principal factors that contribute to the different responses to HF and HC diets are (a) caloric density, (b) sensory properties and palatability, and (c) postabsorptive processing. It is concluded that both calorie intake and metabolic energy expenditure are biased towards weight gain when a HF diet is consumed, and that the high caloric density of high-fat diets plays a primary role in weight gain. Humans may be biologically predisposed to gain weight when a HF diet is consumed.     

A survey and critical evaluation of a dual isotope (Dicopac) vitamin B12 absorption test

The results of all dual isotope tests (2142) carried out on 1989 patients, 807 males (40.6%) and 1182 females (59.4%), during a 10 year period (1976–1985 inclusive) in the Grampian Health Board Area (population 497,272) have been reviewed. Patient age ranged from 5–95 years with 45.5% over 60 years. The referring specialities were Gastroenterology (47.6%), Haematology (11.3%), Paediatries (2.1%) and all others (39.9%). According to the manufacturer's recommended criteria, results were classified as normal in 1054 (49.2%), abnormal in 659 (30.8%), equivocal in 337 (15.7%) and unsatisfactory in 92 (4.3%) tests. Vitamin B₁₂ malabsorption of ileal type was indicated in 544 tests (25.4%) and of gastric type in 115 (5.4%). Of the latter, 76 were related to pernicious anaemia, 10 to previous gastric surgery and 2 to gastric carcinoma. Of the 337 patients with equivocal results, 138 patients were reviewed and 115 (83.3%) found to have a documented cause for gastric malabsorption (96 pernicious anaemia and 19 previous gastric surgery). In 172 patients with proven pernicious anaemia the manufacturer's recommended criteria for gastric malabsorption were completely satisfied in only 76 (44.3%) but 167 (96.5%) had an excretion ratio 1.3 and 127 (73.8%) a ratio 1.7. Unsatisfactory tests were mainly due to incomplete urine collection (91.3%) or contamination with another isotope (5.4%).     

呼出气氢测定试验对飞行人员乳糖酶缺乏症的研究

对66名汉族飞行人员进行乳糖呼出气氢测定试验,乳糖吸收不良的发生率为83.3％,其中乳糖不耐受者占34.6％;与一般汉族人群无明显差别。对10名确定为中度以上乳糖吸收不良的飞行人员进行250ml鲜牛奶的试验结果,有50％呼出气氢含量在正常范围,并无一例出现胃肠道症状。提示较长期食用牛奶未能使乳糖酶缺乏状态发生改变,但每日食用适量牛奶属合理营养。     

Adhesion of carcinoma cells to rat hepatocytes and rat fibronectin is inhibited by the OPAR monoclonal antibody,which is directed against a rat liver-specific carbohydrate epitope

The OPAR mouse monoclonal antibody (mAb) directed against rat hepatocytes was previously shown to inhibit adhesion of TA3/Ha mammary carcinoma cells to hepatocytes. The antigen is abundantly present at the surface of hepatocytes beneath the endothelium of liver capillaries where we have observed invasion of carcinoma cells to occur. The OPAR mAb reacted with three major bands on a Western blot of liver plasma membrane proteins. The same proteins were also seen upon immunoprecipitation from iodinated liver plasma membrane proteins. We have isolated OPAR antigens by lectin wheat germ agglutinin (WGA) and OPAR affinity chromatography. Amino acid sequence analysis revealed that two of the bands were 1-macroglobulin and C4-binding protein, which are serum components produced by hepatocytes. The presence of the epitope on distinct proteins and our previous observation that it can be detected in the Golgi apparatus but not in the endoplasmic reticulum, suggested that OPAR reacts with a liver-specific glycoconjugate. Loss of OPAR reactivity after neuraminidase and N-glycosidase F treatment showed that the epitope contains sialic acid residues on N-linked sugar moieties. OPAR also reacted with rat fibronectin, and inhibited adhesion of TA3/St cells to fibronectin. This explains the inhibition by the OPAR mAb of TA3/St cell adhesion to hepatocytes, which we have shown to be due mainly to interaction with hepatocyte surface-associated fibronectin. However, adhesion of the related TA3/Ha cells to hepatocytes, which is mediated by the ₆P4 integrin, and does not involve binding to fibronectin, is also inhibited. This suggests that ₆₄ on liver-metastasizing carcinoma cells binds to an OPAR epitope-carrying glycoprotein produced by hepatocytes.