Hypothalamic sensitivity to 2-deoxy-D-glucose and glucose: effects on feeding behavior

The effect on food intake of intrahypothalamic deposition of glucose or the glucose metabolic inhibitor 2-deoxy-D-glucose was studied to determine the function of the often hypothesized hypothalamic glucoreceptors in feeding behavior. Our results suggest that the lateral hypothalamic region, as well as the medial hypothalamus, contain glucoreceptive cells that form part of a feeding system.     

妊娠糖尿病孕妇血浆抵抗素水平及其与胰岛素和血糖关系的研究

目的探讨妊娠期糖尿病(GDM)孕妇血浆抵抗素水平及其与胰岛素和血糖的关系。方法采用竞争性酶联免疫吸附法(ELI SA)检测25例GDM组孕妇和30例正常孕妇空腹血浆抵抗素水平;采用葡萄糖氧化酶法测定两组孕妇空腹血糖水平;采用电化学发光法测定两组孕妇的空腹血浆胰岛素水平。结果(1)GDM组孕妇空腹血浆抵抗素水平为(15.32±4.26)μg/L,正常妊娠组孕妇为(11.08±1.52)μg/L两组比较,差异有极显著性(P<0.01);(2)GDM组孕妇空腹血浆胰岛素,血糖水平分别为(13.18±3.25)m IU/L,(9.13±1.34)mmol/L正常妊娠组孕妇分别为(9.10±3.41)m IU/L,(4.72±1.05)mmol/L。两组比较差异有极显著性(P<0.01);(3)GDM组孕妇血浆抵抗素水平与胰岛素、血糖水平呈明显的正相关关系,相关系数(r)分别为0.812,0.573;正常妊娠组孕妇则无相关性。结论GDM孕妇血浆抵抗素水平升高,其抵抗素水平的高低与空腹血浆胰岛素及血糖水平相关。     

Plasma glucose,insulin and catecholamine responses to a Wingate test in physically active women and men

The influence of gender on the glucose response to exercise remains contradictory. Moreover, to our knowledge, the glucoregulatory responses to anaerobic sprint exercise have only been studied in male subjects. Hence, the aim of the present study was to compare glucoregulatory metabolic (glucose and lactate) and hormonal (insulin, catecholamines and estradiol only in women) responses to a 30-s Wingate test, in physically active students. Eight women [19.8 (0.7) years] and eight men [22.0 (0.6) years] participated in a 30-s Wingate test on a bicycle ergometer. Plasma glucose, insulin, and catecholamine concentrations were determined at rest, at the end of both the warm-up and the exercise period and during the recovery (5, 10, 20, and 30 min). Results showed that the plasma glucose increase in response to a 30-s Wingate test was significantly higher in women than in men [0.99 (0.15) versus 0.33 (0.20) mmol l^–1 respectively, P<0.05]. Plasma insulin concentrations peaked at 10 min post-exercise and the increase between this time of recovery and the end of the warm-up was also significantly higher in women than in men [14.7 (2.9) versus 2.3 (1.9) pmol l^–1 respectively, P<0.05]. However, there was no gender difference concerning the catecholamine response. The study indicates a gender-related difference in post-exercise plasma glucose and insulin responses after a supramaximal exercise.     

Serum insulin,glucose and triglyceride responses of Zucker obese and lean rats to cholecystokinin

Zucker obese rats are less sensitive to cholecystokinin (CCK), a putative satiety agent which also stimulates insulin and glucagon release. Changes in serum insulin, glucose and triglycerides, which are elevated in the obese rat, were compared with those in lean rats after saline and CCK-8 injection in fed and non-fed rats. Serum insulin increased 15 min after injection of CCK-8 in both lean and obese rats. In lean rats only, insulin subsequently decreased in both fed and non-fed rats. In both lean and obese rats injected with CCK-8 serum glucose did not change with feeding and was less than in saline-injected rats. While triglyceride concentrations were unaffected by either treatment in lean rats, in obese rats they were increased 100% 15 min after injection of CCK-8 and subsequently decreased in both fed and non-fed rats. Thus, CCK-8 elicited changes which were different from those which occur during normal feeding. Increased serum insulin, glucose and triglycerides which occurred 15 min after injection of saline only in obese rats may be due to increased susceptibility to the stress of being injected and may account for the decreased satiety effect of CCK-8.     

A comparison of islet transplantation and subcutaneous insulin injections for the treatment of diabetes mellitus

Transplantation of the islets of Langerhans has received considerable attention as a means of treating insulin-dependent diabetes mellitus. However, the number of islets needed and the level of plasma glucose control that results from this treatment method still needs to be defined. A pharmacokinetic model of glucose and insulin dynamics which includes the islet insulin response to plasma glucose is used to compare the effectiveness of subcutaneous insulin injections and transplanted islets of Langerhans for the treatment of a hypothetical patient with insulin dependent diabetes mellitus. For a patient receiving 60 U of insulin per day the results show that 500 000 human islets would be needed to obtain glucose control comparable to that obtained with insulin injections and at least 1.5 million human islets are needed to obtain normoglycemia.     

A pocket calculator program to evaluate confidence limits for the relative risk

A program for the TI-59 calculator is given which calculates confidence limits for the relative risk. Figures giving measures of timing and accuracy are presented.     

A solution for linearity, stability and frequency bandwidth in PAM electrocutaneous stimulators'' isolation interface

This paper introduces a novel method to isolate low-level from high-voltage circuits and/or channels of PAM electrocutaneous stimulators in neuromuscular electrical stimulation (NMES). The method avoids problems of linearity and polarization stability of optocouplers and narrow bandwidth of isolation amplifiers. Its main parameters are: carrier frequency of rectangular pulses up to 1 MHz and maximum modulating signal (elliptical or triangular envelopes) of 50 kHz. The circuit has low drift, high-voltage isolation, low-power consumption, requires few components, is battery-operated and ideal for microcomputer interface-based applications.     

A proposed therapy for the encephalopathies of Reye's Syndrome and Hepatic Encephalopathy

On the basis of information known about the pathogenesis of Reye's Syndrome and Hepatic Encephalopathy, and the effect of specific pharmacologic agents at the benzodiazepine receptor it is hypothesized that benzodiazepine receptor antagonists and contragonists will be of therapeutic value in those disorders.     

The fundamental chemistry of life : An attempt to define and identify the basic reaction responsible for life''s creation and evolution

All natural growth follows exponential characteristics which vary from a simple exponential equation (non-solid cancer, bacteria) to complex Gompertzian functions describing solid cancer and multicellular organisms. Like all chemical processes the reagents (energy sources of food) react during life to produce vital energy, but in addition also create the next generation of life. This latter reaction is unique in that a simple proportional increase in the reagents creates an exponential increase in products: it is the sole invariable criterion of all life. The target of combined ionising and non-ionising radiations in cancer cells appears to be identical with this fundamental exponential chemical reaction. Identification of this target as a system of anaerobic glycolysis suggests that life's first reaction is a unique one whereby a simple proportional increase in available glucose causes an exponential proportional increase in energy which is available solely for reproduction.     

Inverse relationship of the velocities of perceived time and information processing events in the brain: A potential bioassay for neural functions: A hypothesis

The velocity of elapsing time is not a constant but a relativistic component in the space-time continuum as postulated by Albert Einstein in his general and special relativity theories. The hypothesis presented here is that there is a biological corollary to relativity theory. It is postulated that biological time perception is also not a constant but is related by an inverse relationship between the velocities of neural processing events and perceived elapsing time. A careful analysis of this relationship may potentially offer a sensitive bioassay to determine the integrity of regional brain function under normal conditions and in the presence of specific disease processes. The mechanism for the biological basis of this theorem depends on the presence of a neural circuit developed through evolution which monitors overall brain efficiency and is coordinately linked to neural time perceiving circuits. Several test approaches are presented to validate the hypothesis of biologic time relativity compared to the rate of neural processing.     

AAQUANT: A computer program for quantitative amino acid analysis of proteins and peptides

Quantitative amino acid analysis is an important tool used in the characterization and structural determination of peptides and proteins. A new computer program, AAQUANT, has been developed specifically to aid researchers in analyzing amino acid composition data. AAQUANT calculates amino acid recoveries, including 95% confidence intervals, following acid hydrolysis of peptides and proteins, and also includes useful routines to locate regions of a specified amino acid composition in known protein sequences, compute amino acid composition reports of known protein sequences, generate proteolytic digestion maps of proteins, and create and edit protein sequence data files. This report describes the AAQUANT routines, and demonstrates the use of the program.     

尼克酰胺与胰腺损伤提取物诱导小鼠骨髓间充质干细胞分化为胰岛素产生细胞的比较

目的 探讨诱导小鼠骨髓间充质干细胞（ＢＭＳＣs）分化为胰岛素产生细胞较好的方法。 方法 大鼠胰腺提取物和尼克酰胺分别诱导小鼠的BMSCs分化,经免疫组织化学、双硫腙染色、放射免疫学方法和RT-PCR技术（Ins-1、Ins-2、Glut-2、GK）鉴定两种诱导方法诱导细胞的分化程度。 结果 两种方法诱导后的细胞均可以表达胰岛素。双硫腙染色和胰岛素免疫组织化学的染色结果发现,两种分化后的细胞无明显差异。放射免疫学检测胰岛素及C肽片段：两种分化后的细胞表达的胰岛素随25mmol/L葡萄糖刺激时间的延长产生的胰岛素分泌曲线有明显差别,尼克酰胺分化的小鼠BMSCs产生的胰岛素产生细胞（IPCs）与正常小鼠胰岛细胞的曲线一致性欠佳,而大鼠胰腺损伤提取物分化的小鼠骨髓间充质干细胞产生的胰岛素产生细胞的分泌曲线一致性很好。尼克酰胺分化后的细胞不能产生C肽片段,而大鼠胰腺损伤提取物能够表达C肽片段。RT-PCR结果显示,尼克酰胺与大鼠胰腺提取物均可以表达胰岛细胞相关的几个mRNA（Ins-1、Ins-2、Glut-2、GK）。 结论 大鼠胰腺提取物与尼克酰胺相比,可能是一种较好的诱导BMSCs分化成熟产生胰岛素的诱导剂。     

QUEST—A package for processing questionnaire text and data

An easy-to-use interactive program (QUEST) has been developed which facilitates the input, updating and checking of patient records from completed questionnaires possibly destined for statistical analysis by SPSS. Using the information about the data available in the SPSS control file, blank questionnaires can be generated, and up to date completed questionnaires printed. Selected cases can be printed out. QUEST is currently being used in four medical studies and one legal study. The program is written in standard Fortran-77 and makes full use of the new features of the language.     

A sample computer system for physiological data acquisition and analysis

This report outlines a sample configuration of a system which records, stores and analyses, graphically and statistically, neurophysiological and cardiovascular recordings during an experiment. The system is composed of sensitive physiological amplifiers, an analog to digital signal conversion board, scientific software, a 80286-based computer with 640 Kb of RAM, and a laser printer. Each component of the system is described along with the specific task(s) it performs.     

A protective role for heme oxygenase-1 in INS-1 cells and rat islets that are exposed to high glucose conditions

Heme oxygenase-1 (HO-1) has been described as an inducible protein that is capable of cytoprotection via radical scavenging and the prevention of apoptosis. Chronic exposure to hyperglycemia can lead to cellular dysfunction that may become irreversible over time, and this process has been termed glucose toxicity. Yet little is known about the relation between glucose toxicity and HO-1 in the islets. The purposes of the present study were to determine whether prolonged exposure of pancreatic islets to a supraphysiologic glucose concentration disrupts the intracellular balance between reactive oxygen species (ROS) and HO-1, and so this causes defective insulin secretion; we also wanted to evaluate a protective role for HO-1 in pancreatic islets against high glucose levels. The intracellular peroxide levels of the pancreatic islets (INS-1 cell, rat islet) were increased in the high glucose media (30 mM glucose or 50 mM ribose). The HO-1 expression was induced in the INS-1 cells by the high glucose levels. Both the HO-1 expression and glucose stimulated insulin secretion (GSIS) was decreased simultaneously in the islets by treatment of the HO-1 antisense. The HO-1 was upregulated in the INS-1 cells by hemin, an inducer of HO-1. And, HO-1 upregulation induced by hemin reversed the GSIS in the islets at a high glucose condition. These results suggest HO-1 seems to mediate the protective response of pancreatic islets against the oxidative stress that is due to high glucose conditions.     

A new computer memory for biology and medicine using the laser card

A new computer memory using a laser beam to impress dimples on a standard credit card has been devised which contains about 2 million bytes (700 typed pages) and which has been formatted with software to permit access to a complete medical record which can be carried by the patient and updated at each encounter with the health care system. The system has been tested in an outpatient clinic with considerable success.     

A pain microcomputer system for clinical and laboratory investigation

This report describes the design and use of a mobile “Pain Microcomputer System” (PMS). As a mobile clinical and laboratory research tool the PMS integrates four functions: (1) psychophysical measurement of behavioral pain responses; (2) psychophysiologic recording, including brain evoked potentials, cortical power spectrum analysis, EKG and EMG; (3) data acquisition, analysis and display; (4) peripheral communications via modem allows interaction with larger computers for more complex data analyses, extensive graphics, etc. A word processor disk facilitates writing of scientific and clinical reports. Present and future capabilities of the system for comprehensive pain research and patient care are discussed.     

Stromelysin, gelatinase A and TIMP-1 in prosthetic interface tissue: a role for macrophages in tissue remodelling

Aseptic loosening of prosthetic components is the most important long-term complication of total joint replacement. To investigate the underlying destructive mechanisms, periprosthetic tissues from both well-fixed and loosened sites from six patients, undergoing surgery for aseptic loosening of knee or hip prostheses, were analysed in detail by immunohistochemical methods for the presence, of matrix metalloproteinases and tissue inhibitor of metalloproteinases-1 (TIMP-1). The tissues contained small numbers of cells positive for either collagenase, stromelysin, gelatinase A or TIMP-1; these were randomly distributed, neither specifically next to the bone interface nor to wear particles, and the number of positive cells did not correlate with macroscopic observations at operation. Gelatinase A was co-localized in cells with prolyl-4-hydroxylase, an enzyme involved in collagen synthesis. The predominant cell type in these tissues was shown to be the macrophage by the use of cell marker antibodies. Dual localization was not technically possible but the results strongly suggest that monocyte/macrophages were the primary source of gelatinase A and TIMP-1. Stromelysin was immunolocalized on connective tissue matrix in four patients, and gelatinase A in one patient, and were also observed in tissues in which there was no evidence of cellular synthesis of these enzymes. This suggests that secretion had taken place previously, resulting in enzyme bound to matrix for some time. Taken together, these data indicate that localized focal connective tissue remodelling occurs in periprosthetic tissues from both well fixed and loosened sites.