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At least 73 records · Page 4Linked to original sources

PubMed1991

Glycaemic thresholds for hypoglycaemic symptoms, impairment of cognitive function, and release of counterregulatory hormones in subjects with functional hypoglycaemia.

Nine patients with food-relieved hypoglycaemic symptoms, in whom insulinoma and other organic diseases presenting with hypoglycaemia had been ruled out, and nine matched controls, participated in the study. Subjects were studied during a 5-h controlled (Biostator) insulin-induced (1-2 mU kg-1 min-1) hypoglycaemic clamp. After 1 h of euglycaemia, we aimed to lower the glucose level in arterialized venous blood in a stepwise manner at 30-min intervals to 3.5, 3.0, and 2.0 mmol l-1, and to withhold these levels for a further 30 min. At euglycaemia and at the end of the latter steps, the visual reaction time and cognitive function (digit span, letter cancellation and trail making) were tested, together with recording symptoms and signs of hypoglycaemia. Counter-regulatory hormones were measured at 20-min intervals. In the patients, clinical signs and symptoms of hypoglycaemia developed at median blood glucose levels of 2.6-2.8 and 2.8-3.1 mmol l-1, respectively. By contrast, the blood glucose levels were 0.4-0.8 mmol l-1 lower in control subjects (P less than 0.05). Similarly, the median threshold for deterioration of visual reaction time was 2.8 mmol l-1 in patients and 2.1 mmol l-1 in controls (P less than 0.01). A similar trend was observed for the results of the neuropsychological tests. Visual reaction time deteriorated in all subjects, whereas the cognitive function of some of the subjects in each group remained unchanged during hypoglycaemia. The glycaemic thresholds for release of cortisol, glucagon and growth hormone were significantly higher in patients (P less than 0.05), whereas the thresholds for catecholamine release showed no significant difference from controls. Despite the comparable glucose infusion rates required to sustain each of the hypoglycaemic levels in the two groups, the control subjects achieved lower glucose levels, suggesting that there is resistance to insulin or glucose in functional hypoglycaemia. In conclusion, the present study suggests that the existence of a higher threshold for symptoms and signs, as well as for deterioration of brain function, may explain every-day hypoglycaemic symptoms, despite normal glucose levels, in subjects with functional hypoglycaemia. However, the hypothesis should be tested further using a blinded approach, including euglycaemic control studies.

Adult↗

PubMed1975

Bacteriophage P22 virion protein which performs an essential early function. II. Characterization of the gene 16 function.

P16 is a virion protein and, as such, is incorporated into the phage head as a step in morphogenesis. The role of P16 in assembly is not essential since particles are formed without this protein which appear normal by electron microscopy. P16 is essential when the particle infects a cell in the following cycle of infection. In the absence of functional P16, the infection does not appear to proceed beyond release of phage DNA from the capsid. No known genes are expressed, no DNA is transcribed, and the host cell survives the infection, continuing to grow and divide normally. The P16 function is required only during infection for the expression of phage functions. Induction in the absence of P16 proceeds with the expression of early and late genes and results in particle formation. P16 must be incorporated during morphogenesis into progeny particles after both infection and induction for the progeny to be infectious. The P16 function is necessary for transduction as well as for infection. Its activity is independent of new protein synthesis and it is not under immunity control. P16 can act in trans, but appears to act preferentially on the phage or phage DNA with which it is packaged. The data from complementation studies are compatible with P16 release from the capsid with the phage DNA. In the absence of P16 the infection is blocked, but the phage genome is not degraded. The various roles which have been ruled out for P16 are: (i) an early regulatory function, (ii) an enzymatic activity necessary for phage production, (iii) protection of phage DNA from host degradation enzymes, (iv) any generalized alteration of the host cell, (v) binding parental DNA to the replication complex, and (vi) any direct involvement in the replication of P22 DNA. P16 can be responsible for: (i) complete release of the DNA and disengagement from the capsid, (ii) bringing the released DNA to some necessary cell site or compartment such as the cytoplasm, (iii) removal of other virion proteins from the injected DNA, and (iv) alterations of the structure of the injected DNA.

Adsorption↗

PubMed1992

[Characterization of thyroglobulin in a patient with functioning and non-functioning benign thyroid tumors].

The chemical and immunological properties of thyroglobulin (Tg) in tissue obtained from a patient co-existed with two types of thyroid tumors, i.e., functioning and non-functioning, and were compared with the properties of Tg that was isolated from adjacent peripheral tissue. In the present observations, the Tg content was markedly increased in the non-functioning thyroid tumor. On the other hand, the Tg content in the functioning tumor was at the normal level. The iodine content of Tg was significantly lower in the non-functioning tumor than in peripheral tissues. Affinity with Lectins differed among Tg preparations, suggesting that the carbohydrate chain in the Tg was different in each nodule in a single individual.

Adenoma↗

PubMed1992

[Erectile function and urinary function].

In recent years, with the great advance in neuro-urophysiological concept, the evaluation and limitations of clinical investigation for sexual (erection) function and bladder (urinary) function are continuously changing, so they should be correctly recognized at the time of actual interpretation. The common problems on these functional tests are standardization of terminology and of methodology, and difference of individual sensitivity. From a viewpoint of respective evaluation and limitations, AVSS, NPT, papaverine test, BCR for erectile function tests and CM, UFM, EMG, complex urodynamics for urinary function tests are reviewed.

Autonomic Nervous System Diseases↗

PubMed1990

Functional assessment of elderly patients after percutaneous aortic balloon valvuloplasty: New York Heart Association classification versus functional status questionnaire.

Monitoring functional status in patients with cardiac disease has traditionally been done by using the New York Heart Association (NYHA) classification system. For various reasons, we found the NYHA system difficult to apply to elderly patients. We proposed that the functional status questionnaire (FSQ), which measures the ability to perform tasks, would more accurately assess the functional status of the elderly. In a study in 37 patients with a mean age of 76 years, who had aortic stenosis, we measured FSQ and NYHA scores at baseline, 1 month and 3 months. The difference in questionnaires was evident by the 3-month measurement. Individual patients were better evaluated by the FSQ. Six patients had an FSQ score of less than 72 (suggesting severe functional impairment) at 3 months but only two patients gave symptoms scored as NYHA class III or IV (cardiac disability). Five of six patients had a recurrent cardiac event subsequent to the 3-month follow-up. Changes in functional performance preceded symptomatic deterioration that was reflected only by the FSQ scores. The FSQ system more reliably predicted outcome than the NYHA system and appears to be a more useful tool in the evaluation of elderly patients with cardiac disease.

Activities of Daily Living↗

PubMedDate not supplied

[Pathogenesis of functional retardation of physical and sexual development in adolescents. Status of somatotropic and gonadotropic function].

A study of somatotropic and gonadotropic functions in male adolescents with functional retardation of physical and sexual development has shown an important role of the deficiency of gonadotropins, especially FSH, in the pathogenesis of this condition. LH secretion in retarded physical development (RPD) is lowered to a lesser degree and positively correlates with testosterone deficiency. The feedback in the hypothalamohypophyseogonadal function in RPD is less frequently affected and to a lesser degree than gonadotropic functions. Of the tested methods (tests with TRH, L-DOPA and bromocriptine) STH reserves are better revealed with L-DOPA and TRH tests, gonadotropic reserves, especially LH,--with TRH and bromocriptine tests. The stimulating TRH effect on the growth hormone is indicative of the versatility and nonspecificity of its action on the pituitary gland in functional developmental disorders.

Adolescent↗

PubMed1978

Obesity and thyroid function. 3. Relationship between some indicators of thyroid function and the energy metabolism of striated muscle in obese women.

1. In a group of 23 obese women the relations between some indicators of thyroid function (thyroxine-binding globuline--T4BG, triiodothyronine-binding globuline--T3BG, Achilles tendon reflex--ART) on the one hand and activities of enzymes of the energy metabolism (hexokinase--HK, triose phosphate dehydrogenase--TPDH, lactate dehydrogenase--LDH, glycerol-3-phosphate dehydrogenase--GPDH, citrate synthease--CS, malate dehydrogenase--MDH, hydroxyacyl--COA dehydrogenase) in the quadriceps femoris muscle on the other hand were investigated. 2. Correlations were found between T4BG and TPDH, LDH and GPDH activities, between T3BG and TPDH and GPDH activities and between the value of the Achilles tendon reflex and TPDH activity. Functionally these enzymes activities are associated with glycolysis and hydrogen transport from cytoplasmatic NADH2. No correlations were found between enzymes of the aerobic metabolism incl. enzymes of fatty acid oxidation and indicators of thyroid function. 3. The results indicate a relationship between thyroid function and enzymes involved in glycolysis and hydrogen transport from cytoplasmatic NADH2. They do not suggest, however, the unequivocal conclusion that in obese women with reduced thyroid function there is a generally reduced energy supplying metabolism in skeletal muscle.

Achilles Tendon↗

PubMed1978

Adherent cell function in murine T lymphocyte antigen recognition. II. Definition of genetically restricted and nonrestricted macrophage functions in T cell proliferation.

The mechanisms by which adherent cells, presumably of mononuclear phagocytic lineage, influence in vitro antigen-specific activation of murine T lymphocytes was examined. Two distinct functions for macrophages could be discerned. One macrophage function is dependent on a soluble factor produced by cultured adherent cells and is most easily studied with complex multideterminant antigens. This factor is neither antigen-specific nor MHC-restricted in its action in that PEC, regardless of haplotype, produce factor in the absence of antigen. A second function, antigen-specific T cell activation, is seen when antigens of more restricted heterogeneity are used, such as those under the control of Ir genes. This latter activity demands identity or partial identity between the antigen-presenting cell and the primed T cell, thus suggesting an additional specific, genetically restricted function for macrophages in in vitro antigen recognition. Whether these adherent cell functions are mediated by all or distinct subsets of cells was not established.

Animals↗

PubMed1992

RETRACTED: Right ventricular function in patients with reduced left ventricular function undergoing myocardial revascularization.

Complex interrelationships exist between the right (RV) and the left ventricles (LV). Therefore, in 30 consecutive patients with reduced LV function (left ventricular ejection fraction [LVEF]) less than 40% undergoing myocardial revascularization, RV hemodynamics were studied from the beginning of anesthesia until the end of the operation. The data were compared with 30 consecutive patients with normal LVEF (greater than 70%). Ventricular function was assessed during left heart catheterization, which was carried out within 1 month of the operation. In addition to standard hemodynamic variables, RV ejection fraction (RVEF), RV end-diastolic volume (RVEDV), and RV end-systolic volume (RVESV) were monitored by the thermodilution technique. The two groups did not differ preoperatively with regard to RVEF, pressure (MAP, PAP, PCWP, RAP, RVPsyst, RVEDP), cardiac index (CI), and volume variables (RVESV, RVEDV). However, when the group with preoperatively reduced LVEF was subdivided into patients with severely reduced LVEF (less than 30%; n = 14; mean value 25.1%) and patients with moderately reduced LVEF (30%-40%; n = 16; mean value 37.3%), RVEF was significantly lower in the patients with a LVEF below 30% throughout the entire investigation period. RVEDV and RVESV were significantly higher in these patients. In conjunction with the lower RVEF and normal PAP, this suggests reduced RV function. It can be concluded that a severely reduced preoperative LVEF (less than 30%) may also be associated with impaired RV function.

Analysis of Variance↗

PubMed1991

Primary biliary cirrhosis: relation between hepatic function and pulmonary function in patients who never smoked.

We studied the relationship between selected variables of hepatic and pulmonary function in 47 patients with primary biliary cirrhosis, who were participating in a prospective study to assess sequential pulmonary function at yearly intervals. An additional 20 patients with primary biliary cirrhosis, who were liver transplant candidates awaiting transplantation, were studied. None of the 67 patients ever smoked cigarettes. Severity of primary biliary cirrhosis was characterized by histological stage and the Mayo risk score derived from a Cox regression model that used the following variables: serum bilirubin and serum albumin levels, age, prothrombin time and clinical severity of edema. Pulmonary function assessment included key variables describing expiratory airflow (forced expiratory volume in 1 sec divided by forced vital capacity) and efficiency of gas exchange (steady-state diffusing capacity for carbon monoxide). We found a significant relationship between histological stage of primary biliary cirrhosis and steady-state diffusing capacity (p = 0.02) and between the Mayo risk score for disease severity and steady-state diffusing capacity (p = 0.03). Progressive deterioration of steady-state diffusing capacity was associated with increasing severity of primary biliary cirrhosis. No relationship existed between pulmonary function and the presence of sicca complex or Sjögren's syndrome or the clinical manifestations of portal hypertension (e.g., esophageal varices, ascites and splenomegaly). No significant relationship existed between expiratory airflow and severity of primary biliary cirrhosis. We conclude that in patients with primary biliary cirrhosis who have never smoked, a statistically significant relationship exists between the severity of the liver disease and the efficiency of gas exchange measured by steady-state diffusing capacity.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗

PubMed1992

[The effect of acute cellular rejection on liver function following orthoptic liver transplantation. Quantitative functional studies with the 14C-aminopyrine breath test].

To test the effect of acute cellular rejection on liver function as represented by cytochrome-P-450 enzyme activity, the 14C-aminopyrine breath test (ABT) was performed prospectively in 46 patients (31 men, 15 women; mean age 48 [15-66] years) who had undergone a total of 50 orthotopic liver transplantations. Routine biochemical tests were performed daily until the 30th postoperative day, while the ABT was done daily on days 1-10 and three times weekly on days 11-30, and liver puncture biopsies were obtained once weekly or more often if there was clinical suspicion of rejection. Histologically confirmed cellular rejection occurred within the stated period of observation in eight patients (five women, three men; median age 45 [18-59] years). Results of routine laboratory tests (transaminases, bilirubin, thromboplastin time), as well as bile-flow and body temperature, did not vary uniformly. On the other hand, results of ABT at the time of rejection showed a decrease in all patients by an average of 65% (P < 0.01). Changes in the ABT preceded those in other tests by 1-2 days in four patients, being the only measurable functional abnormality in one. All rejection episodes responded to glucocorticoid pulse-treatment (three times 1 g methyl-prednisolone). Using ABT results as criterion, liver function became normal after the glucocorticoid injection within 4-11 days. These data indicate that the ABT is suitable in the routine monitoring of transplant function, thus facilitating early diagnosis and controlled treatment of acute cellular rejection.

Acute Disease↗

PubMed1988

Relationship of lung function loss to level of initial function: correcting for measurement error using the reliability coefficient.

The regression of lung function change on the initial lung function level is biased when the initial level is measured with random error. Several methods have been proposed to obtain unbiased estimates of regression coefficients in such circumstances. We apply these methods to examine the relationship between lung function loss over 11 years and its initial level in 433 men aged about 20 when first seen. On theoretical and practical grounds the best method is the correction of the regression coefficient using the reliability coefficient. This is defined as the ratio of the error free variance to the variance of the variable measured with error, and is easily estimated as the correlation between repeat measurements of the underlying level. In young men the loss of some lung functions (forced vital capacity [FVC], forced expiratory volume in one second [FEV1], forced expiratory flow in the middle half of expiration, and the ratio FEV1/FVC) do not appear to be related to initial level.

Adult↗

PubMed1985

Deficiency of the adhesive protein complex lymphocyte function antigen 1, complement receptor type 3, glycoprotein p150,95 in a girl with recurrent bacterial infections. Effects on phagocytic cells and lymphocyte functions.

A patient presenting delayed umbilical cord detachment, severe recurrent bacterial infections, and inability to form pus exhibited a profound defect in the expression of alpha- and beta-chains of the receptor for the C3bi fragment of C3 (CR3), lymphocyte function antigen 1 (LFA-1) molecule, and the p150,95 molecule found on neutrophils, monocytes, and lymphocyte membranes. This was shown by immunofluorescence studies using specific monoclonal antibodies, rosette formation with C3bi-coated erythrocytes, and immunoprecipitation for the LFA-1 complex. These membrane defects were responsible for abnormal phagocytic cell functions including adherence to nylon wool, cell movement, phagocytosis, and opsonized particle-induced oxidative response and for defective natural killer cell activity. In addition, lymphocyte function deficiencies previously unobserved in this disease were found. Cytolytic T lymphocyte activity was profoundly reduced; alpha- and gamma-interferon production were impaired. Finally, there was no antibody production to vaccinal antigens whereas the antibody responses to polysaccharides and to cytomegalovirus were found to be normal. The cytotoxic T cell deficiency could be expected from previous blocking experiments of this function with monoclonal antibodies to LFA-1 and is probably related to an extremely severe deficiency in LFA-1 expression in this patient. Anomalies in interferon and in antibody production suggest additional role(s) of the LFA-1 complex in monocyte/T lymphocyte/B lymphocyte cell interactions that have not yet been envisaged.

Antibodies, Monoclonal↗

PubMed1977

Clinical significance of pulmonary function tests. Pulmonary function after uncomplicated myocardial infarction.

Derangement of pulmonary function following myocardial infarction is related to the severity of hemodynamic dysfunction. Abnormalities of pulmonary function appear even in patients without clinical or radiologic evidence of congestive failure. There is a reduction in vital capacity and rates of air flow. There is evidence for dysfunction of "small airways" and diminished ventilation to dependent parts of the lung. Total lung capacity may be normal or reduced, and residual volume may be increased slightly in uncomplicated myocardial infarction. Residual volume falls with more pronounced pulmonary congestion and edema. Distribution of pulmonary perfusion is altered after myocardial infarction, with a shift of perfusion away from the dependent parts of the lung (bases) towards the apices. Pulmonary gas exchange is impaired, with hypoxemia (due to both ventilation-perfusion inequality and increased shunting); and the diffusing capacity for carbon monoxide is diminished. Dead space is increased. The basic pathophysiologic mechanism responsible for abnormalities of pulmonary function is increased pulmonary water, which may be very minimal with uncomplicated myocardial infarction and stay primarily in the pulmonary interstitial space, but becomes progressively more severe with eventual alveolar flooding and marked impairment of pulmonary function.

Humans↗

PubMedDate not supplied

Long-term deficits of goal-directed vestibulo-ocular function following total unilateral loss of peripheral vestibular function.

Brief whole-body movements (+/- 5 to 170 degrees/s peak velocity; approximately equal to 0.5 s duration), applied during 1.44-s intervals of total darkness while subjects "looked" at a just-viewed target, were used to examine vestibulo-ocular function in 3 patients who had compensated to total unilateral loss of peripheral vestibular function. We found that the combined effects of slow-phase and saccadic eye movements both tended to keep the eyes stabilized on the unseen target. Compensatory slow-phases elicited during rapid head movements ipsilateral to (i.e., towards) the lesion were only about 60% as effective as those elicited during rapid contralateral movements. Compensatory gaze-correcting saccades tended to supplement deficient slow-phase movements, especially during rapid ipsilateral head movement. However, the gaze-correcting effect of saccades was only about half of the required for perfect stabilization. Thus, two functional vestibular deficits were observed during rapid ipsilateral head movements: (1) reduced slow-phase stabilization, and (2) reduced saccadic ability to adequately supplement the deficient slow phases. However, overall vestibular functional capability, as assessed by observation of the net effect of both slow phases and saccades, was much better than would be indicated by conventional observation of slow-phase movements alone.

Adult↗

PubMed1991

The relation between motor function development and vestibular function tests in four children with inner ear anomaly.

It is well known that the development of motor function is frequently retarded in children with congenital deafness, particularly in cases of inner ear anomaly. The relation between the results of vestibular function tests and the development of motor function in 4 children with inner ear anomaly is studied. CT scan obtained from these cases revealed the absence of lateral semicircular canals in both ears. There were no responses to caloric stimulation using 40 ml ice-water. However, damped rotation test elicited per-rotatory nystagmus in all cases. In contrast to this result, the same nystagmus was provoked only in 2 cases in Barany rotation test. Early development of motor functions, especially that of first walk, was more retarded in the 2 cases showing no per-rotatory nystagmus in Barany rotation test than in the other 2 positive cases.

Child↗

PubMed1987

Regional time-based functional imaging of hepatocyte function.

Hepatocyte function was analyzed following the injection of 5 mCi of Tc-99m disofenin by the computer generation of three kinds of functional images designed to portray regional rates of hepatic uptake. Nineteen patients were analyzed, of whom eight had no overt liver disease, five had active hepatitis, five had cirrhosis, and one had acute cholecystitis. Functional images were graded according to lack of regional homogeneity of accumulation. Uptake kinetics were found to be significantly more homogeneous in normal subjects, becoming increasingly heterogeneous in hepatitis and cirrhosis patients, respectively. Thus functional imaging may provide a tool for the quantitative analysis of parenchymal disruption in liver disease.

Adult↗

PubMed1977

Kinetics of hepatocellular proliferation as a function of the microvascular structure and functional state of the liver.

An analysis of hepatocellular proliferation in regenerating rat liver reveals a dependence of kinetic parameters on the microvascular structure of the liver. Influx kinetics of hepatocytes into DNA synthesis as well as cell cycle phases vary in different parts of the liver lobule between the afferent and efferent vascular poles. Heterogeneity of the proliferative response and size limitations on cell cycle compartments appear to be intimately related to the actual functional state of the individual liver cell. Modifications of liver cell functions result in variations of the proliferative activity. Phenobarbital-induced hypertrophy of hepatocytes reveals a permissive action on G1- S influx. Selective destruction of the subpopulations, by allyl formate, leads to a new functional determination of the residual liver and to a change in proliferative compartments. Maximum modulation of cell cycle compartments is obtained by hydroxyurea-induced synchronization of hepatocytes after partial liver resection. During hydroxyurea treatment, the regenerating liver shows a pronounced cellular hypertrophy. After release from hydroxyurea block, cells embark on DNA synthesis simultaneously. The DNA synthesizing compartment comprises almost the entire liver cell population. Heptotrophic factors might play a part in regulating or modifying hepatocellular function and proliferative response after cell loss.

Allyl Compounds↗