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Biomedical subjects

A Lifshitz

Publications and source records attributed to A Lifshitz.

At least 19 recordsLinked to original sources
PubMed1998

Insulin sensitivity and sex steroid hormone levels during the menstrual cycle in healthy women with non-insulin-dependent diabetic parents.

OBJECTIVE: To identify the effect of the menstrual cycle and sex steroid hormone levels on insulin sensitivity in healthy women with non-insulin-dependent diabetic parents. METHODS: A clinical trial was realized in 6 healthy women with non-insulin-dependent diabetic parents and in 6 control subjects. In both phases of the menstrual cycle the following tests were made: insulin tolerance test, metabolic profile, and sex steroid hormone levels. RESULTS: Insulin sensitivity was significantly lower in the follicular (p = 0.004) and luteal (p = 0.01) phases of the menstrual cycle in probands compared with controls. In the luteal phase dehydroepiandrosterone was higher in probands than in controls (p = 0.009). CONCLUSIONS: Healthy women with non-insulin-dependent diabetic parents had a lower insulin sensitivity in both phases of the menstrual cycle compared with the control group. Dehydroepiandrosterone was higher in the luteal phase in probands than controls.

Adult↗
PubMed1997

Changes in human serum antioxidant capacity and peroxidation after four months of exposure to air pollutants.

Twenty-one adult volunteers (aged 27-32 years), who had been living in Mexico City for four continuous months (physicians working as fellows) were studied the first and sixteenth week of their stay in order to learn the effects of the pollutants contained in Mexico City's atmosphere on some serum biochemical parameters. The activity of serum superoxide dismutase (SOD) decreased after 16 weeks in comparison with the values obtained the first week (109.6 to 56.9 mU/mg protein; 50% less). In contrast, the inhibitory capacity of serum vs. induced in vitro lipoperoxidation increased in relation to the length of stay (22%). The serum levels of thiobarbituric-reactive material also decreased in almost 30% (from 6.10 to 4.12 nmol). The other lipoperoxides measured were unchanged (chromolipids and diene conjugation). We propose that this may be as a result of the adaptative capacity of the human organism, within a pollutant atmosphere in which the ozone levels might participate in a decrease of SOD activity during chronic exposure, to air pollution.

Adaptation, Physiological↗
PubMed1997

Metabolic profile and insulin sensitivity in healthy young Mexicans with a strong family history of non-insulin-dependent diabetes mellitus in the paternal branch.

The objective was to identify early metabolic defects and insulin sensitivity in a group of healthy young Mexicans with a family history of NIDDM in first and second degree on the paternal branch. The design was a cross-sectional study, and the setting was a hospital and a school of medicine in Guadalajara, Jalisco, Mexico. The subjects were 20 healthy, non-obese, young (age 19-20 years), born in Mexico, with family history of NIDDM in first and second degree in the paternal branch, and 20 controls. Measurements were serum values of creatinin, uric acid, total cholesterol, high-density lipoprotein cholesterol, triglycerides, glucose, and insulin, insulin tolerance test, glucose/insulin ratio, LDL cholesterol, VLDL cholesterol, total cholesterol/HDL cholesterol ratio and LDL cholesterol/HDL cholesterol ratio. In terms of results, only the total cholesterol was slightly, although significantly (p = 0.05) higher in probands (4.3 +/- 0.5 mmol/L) than in control subjects (3.9 +/- 0.5 mmol/L). In conclusion, healthy young Mexicans with a strong family history of NIDDM in the paternal branch were not different in insulin sensitivity from those without family history of NIDDM, and only showed a slight increase in serum total cholesterol.

Adult↗
PubMed1996

Increased adhesiveness of peripheral blood leukocytes corresponds to the appearance of expansion following anterior wall myocardial infarction.

The appearance of increased leukocyte adhesiveness/aggregation as an inflammatory marker in the peripheral blood of patients with anterior wall myocardial infarction was monitored. Of the 26 patients included in the study, 7 had infarct expansion as shown by an enlargement of left ventricular end-diastolic volume. The percent of aggregated leukocytes in the peripheral blood of patients with expansion (29.7 +/- 15.5%) was significantly higher (p = 0.01) than that obtained from patients with no expansion (18.5 +/- 6.8%). The lack of significant differences in peak creatine kinase concentrations between patients with and without expansion suggests that infarct size is not necessarily the main determinant for the appearance of expansion; an increased inflammatory reaction could be a contributory factor.

Cell Adhesion↗
PubMed1996

Dexamethasone as an adjuvant therapy for anovulatory, normoandrogenic patients during ovulation induction with exogenous gonadotropins.

OBJECTIVE: The objective of our study was to explore the effect of dexamethasone (DEX), a highly potent, long-acting glucocorticoid, on the treatment outcome of 74 anovulatory women aged 21 to 29 years, with normal gonadotropins, androgen, and prolactin (PRL) serum levels who failed to conceive on antiestrogen therapy. METHODS: The patients received human menopausal gonadotropin/human chorionic gonadotropin (hMG/hCG) for ovulation induction. Starting on day 4 of the induced menstruation, hMG was administered in combination with DEX, 0.5 mg at night, or without DEX as an adjuvant treatment. The total amount of gonadotropins used, time required for stimulation, percentage of fertilization, serum estradiol levels, pregnancy rate, cumulative pregnancy rate, and abortions were recorded. RESULTS: There were no differences in either the cumulative pregnancy rate (54.1% in the DEX group and 52.7% in the untreated group) or the abortion rates (21.7% in the DEX group compared to 20.8% in the untreated group). The other parameters investigated also did not differ significantly between the groups. CONCLUSIONS: The overall results did not support DEX as a clinically useful adjuvant therapy for anovulatory, normoandrogenic patients.

Abortion, Spontaneous↗
PubMed1996

Insulin resistance in offspring of hypertensive subjects.

OBJECTIVE: To assess whether apparently healthy subjects with a family history of systemic hypertension have a higher risk of presenting the insulin resistance syndrome. SUBJECTS: Three hundred and eighty-six subjects aged 20-65 years. SETTING: A middle socio-economic class urban community from Mexico City. METHOD: All subjects and, when necessary, their first-degree relatives, answered a questionnaire and underwent a physical examination with measurement of height, weight and blood pressure. Serum insulin, glucose, cholesterol and triglycerides were measured during fasting and 2 h after an oral load of 75 g glucose. RESULTS: A family history of systemic hypertension was present for 167 (43%) of the subjects, of whom 123 (31%) were obese. Subjects with a family history of hypertension had higher systolic blood pressures than did those without such a history (120 +/- 15 versus 115 +/- 10 mmHg). In the logistic regression model, the body mass index and age showed statistically significant effects on the fasting glucose:insulin ratio and on serum insulin levels after an oral load of glucose. When men and women were analysed separately, only in men were higher systolic and mean blood pressures and lower glucose:insulin ratios observed. In the logistic regression analysis the body mass index was a significant predictor of the glucose:insulin ratio and serum insulin levels after an oral load of glucose, especially in men. CONCLUSION: Apparently healthy male offspring of hypertensive parents have higher blood pressure levels and lower insulin sensitivities than do offspring of normotensive parents. Insulin resistance was related to obesity, but not to a family history of hypertension, as had previously been reported by other research groups.

Adult↗
PubMed1996

Possible effect of air pollutants (Mexico City) on superoxide dismutase activity and serum lipoperoxides in the human adult.

The action of air pollutants, through their constituents, (O3, NO2, tobacco smoke) are capable of causing damage due to their lipoperoxidative properties or, indirectly, by inducing production of free radicals. As a consequence of photochemical processes, the ozone levels in the atmosphere of Mexico City are generally higher (mean of 0.325 ppm; period between 1987-1992) and may be harmful to health. Sixty two volunteers (medical doctors), aged 27-32 years, were divided into three groups. Group A was composed of those persons (17) who had never lived in Mexico City; a second group (B) (21) had recently arrived in Mexico City (1-8 days); and a third group (C) (24) who had permanently resided in Mexico City. Serum was obtained from fresh whole blood. Superoxide dismutase (SOD) activity and thiobarbituric acid-reactive materials were higher in group B while chromolipids and the serum inhibitory capacity (for lipoperoxidation) was higher in group C. The acute exposure to pollutants in group B apparently may have induced SOD as an antioxidant defense and was responsible for the increased level of TBA reactive material. In group C, the significant finding is better antioxidative defenses and slightly higher chromolipids.

Adult↗
PubMed1996

Circadian variation of human acute phase response.

Circadian variation of temperature, both normal and febrile, is a well known fact. Mediators of fever are also regulators of acute phase response and are associated with stimulation of pituitary hormone production related with defervescence and with a circadian pattern of secretion. Acute phase response may consequently have circadian variations in its components. Measurements of temperature, erythrocyte sedimentation rate, complete blood cell count, serum cortisol and fibrinogen were made at 7:00, 15:00, and 23:00 h during two consecutive days in 35 patients with fever and acute infection, 15 patients with clinically active ankylosing spondylitis without fever and 10 healthy volunteers. Temperature curves showed statistically significant circadian rhythms, with higher values at night and lower ones during early morning. Erythrocyte sedimentation rate, leukocyte count and fibrinogen also showed statistically significant circadian rhythms, but with higher values at 15:00 h. Serum cortisol also showed statistically significant circadian rhythmicity but with a higher rhythm adjusted mean (MESOR), and a 100 degrees (6 h) phase shift in patients with fever, as compared to patients with ankylosing spondylitis and healthy controls. In conclusion, components of acute phase response, including fever, have circadian rhythmicity, but asynchronically. Differences between fever and ankylosing spondylitis can be due to the intensity of acute phase response stimulation.

Acute-Phase Reaction↗
PubMed1996

Predictive value of signs and symptoms in the diagnosis of subarachnoid hemorrhage among stroke patients.

Clinical diagnosis of subarachnoid hemorrhage (SAH) is frequently misdiagnosed with intracerebral hemorrhage (ICH) or cerebral infarction (CI), which delays appropriate referral. This study was undertaken to create a clinical index to select, among stroke patients, those with the highest probability of having a SAH. Clinical data of patients with acute stroke were evaluated with the X2 and the Fisher exact test; a p value < 0.05 was considered significant. Significant variables were included in a "log-lineal regression analysis" where those with an odds ratio (OR) 95% confidence limits not including the unit were considered to construct an index using the odds ratio coefficient (C). The results indicated that of 197 records which were included, 22 cases of SAH and 175 of ICH or CI were demonstrated. Kappa coefficients for observer variation in clinical data retrieval was 0.91. After "log-lineal regression analysis" was carried out the following variables were significant: neck stiffness (C = 3, OR = 21); lack of focal neurologic signs (C = 2, OR = 6.88); and age < or = 60 years (C = 1.5, OR = 4.35). A fourth variable, seizures (C = 1, OR = 3.25), was marginally significant (p = 0.07), but added predictive value to the index. The positive predictive values of the sum of the coefficients were: 0 = 0%; 1-2 = 3%; 2.5-3.5 = 21%; 4-5 = 40%; 6.5 = 75%; 7.5 = 100%. In conclusion, when a stroke patient shows neck stiffness, or any combination of young age, lack of focal neurologic signs or seizures (a score > or = 2.5, the index has a 91% sensitivity and 82% specificity), he/she must be referred to a tertiary care center.

Adolescent↗
PubMed1996

The effect of estrogen replacement therapy on plasma serotonin and catecholamines of postmenopausal women.

We examined the effect of estrogen replacement therapy (ERT) on plasma serotonin (5HT) and norepinephrine (NE) and their correlation with serum estradiol, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in 12 postmenopausal women. Plasma 5HT and NE, estrogen, progesterone, LH and FSH were examined every 4 days for 2 consecutive months (before and during ERT). Serotonin values were low (32.29 +/- 38.36 nmol/l) and showed an intrinsic spontaneous cyclicity with a nadir every 10-11 days. Plasma NE was similar to that observed during the follicular phase of the ovulatory cycle (1,216.8 +/- 503.4 pmol/l) and showed no cyclicity. ERT significantly increased mean (+/- SD) serum estrogen values (from 95.40 +/- 73.31 to 390.72 +/- 347.17 pmol/l, P = 0.0001), significantly decreased serum FSH (from 84.04 +/- 14.97 to 52.97 +/- 20.74 mIU/ml, P = 0.0001) and LH (from 35.35 +/- 13.82 mIU/ml to 29.69 +/- 16.46 mIU/ml, P = 0.03). Plasma 5HT levels showed a tendency to rise under the influence of ERT, but this increase was not statistically significant. Plasma NE decreased significantly from 1,216.8 +/- 503.4 to 994.1 +/- 353.89 pmol/l, P <0.05. In conclusion, plasma serotonin in postmenopausal women has a 10-11 day cycle and is significantly lower than in the follicular phase of ovulating women. Plasma NE shows no cyclicity and is significantly decreased by ERT.

Aged↗
PubMed1995

An assessment of cerebrospinal fluid's total creatine-kinase activity in the differential diagnosis of metabolic and organic causes of coma.

The objective of the study was to assess total cerebrospinal creatinine-kinase activity (CSF-CK) measurement in differential diagnosis of "metabolic" and organic causes of coma. The setting for the study was a tertiary care reference medical center and community general hospital. The design of the study was a series of consecutive patients with profound coma (Glasgow scale ratings between 3 and 6) as the presenting complaint to the emergency room and controls. Measurements and main results were as follows: CSF-CK was measured in 103 consecutive patients including 18 patients with metabolic causes of coma, 27 patients with organic causes of coma, 18 patients scheduled for elective orthopedic surgery with epidural anesthesia and 27 patients with compressive myelopathy and radiculopathy. CSF-CK activities were significantly different between groups (H = 29.48, p < 0.001, Kruskal-Wallis test), controls had a median of 0 mU/ml (range 0-16 mU/ml), patients with metabolic causes of coma had a median of 0 mU/ml (range 0-65 mU/ml), patients with compressive myelopathy or radiculopathy had a median of 19 mU/ml (range 0-80 mU/ml), and patients with organic causes of coma had a median of 20 mU/ml (range 0-400 mU/ml). The test sensitivity was 83% (95% confidence interval (CI 65-100%) specificity 62% (CI 43-80%) positive predictive value 60% (CI 49-79%) and negative predictive value 85% (CI 75-95%). The conclusion of the study was that the test is useful for ruling out metabolic causes of coma when CSF-CK activity is high (i.e., above 16 mU/ml).

Adult↗
PubMed1995

Enteric viral infections in Gaza children--incidence and associated factors and phenomena.

Regular administration of live attenuated polio vaccine (TOPV) to babies in Gaza failed to give adequate protection against infection and disease with wild polio viruses. The possible interference of the "take" of the vaccine was investigated by obtaining demographic, socioeconomic and virological data. More than 100 babies during their first year of life, and their families, were followed. Enteroviruses were isolated in 25.3% and 7.9% of stool samples obtained from healthy babies and babies with diarrhea, respectively. In the same cases, rotaviruses were detected in only 1.9% and 1.4% respectively. It appears that the most common candidates for viral interference in this population are enteroviruses and not rotaviruses, either in healthy babies or in babies suffering from diarrhea.

Adult↗
PubMed1994

Fever: friend or foe?

Fever is one of the most common manifestations of disease. The patient's relatives and physicians' concern about it is due to the fact that fever reflects that something in the body is not working well. However, the question on fever as convenient or harmful is not yet completely answered. The purpose of this paper is to examine the arguments on both sides and to guide on the convenience of antipyretic treatment.

Analgesics, Non-Narcotic↗
PubMed1991

Corynebacterium CDC group A-4 native valve endocarditis.

A patient with endocarditis caused by Corynebacterium CDC Group A-4 is described. This is the first case in the literature of endocarditis caused by this bacteria, and is unique in that the patient was immune competent and the infection occurred on a native valve. This case illustrates that corynebacteria cannot be considered a contaminant and that the exact pathogen should be identified.

Aged↗
PubMed1991

Possible role for a plasma factor in the induction and/or maintenance of the state of leukocyte adhesiveness/aggregation in the peripheral blood. A study of mothers and their newborns.

The adhesive property of white blood cells is essential for a normal immune response. We examined the state of leukocyte adhesiveness/aggregation (LAA) in the peripheral blood of 31 mothers and their newborns by means of a direct slide test and found it to differ significantly, the respective per cents of aggregated leukocytes found in the peripheral blood being 15 +/- 6.4 and 5 +/- 3.3 (mean +/- SD). However, the particle concentration of white blood cells in the peripheral blood did not differ significantly (14.2 +/- 4.4 and 13.6 +/- x 10(9) l-1). By incubating a mother's plasma with her newborn's whole blood we could induce a significant (p less than 0.0001) increment in the state of LAA. We conclude that deficiency of a plasma factor that does not cross the placenta is responsible for the low LAA in the newborn's peripheral blood.

Cell Adhesion↗
PubMed1990

How to predict the immune status of poliovirus vaccinees? A comparison of virus neutralization at a very low serum dilution versus ELISA in a cohort of infants.

A cohort of children from Gaza was observed from birth to the age of one year. Blood specimens were collected at birth, before and after poliovirus vaccination and at one year of age. Poliovirus immunity before and after vaccination was assessed by ELISA and virus neutralization (NT). Positive predictive values for ELISA were between 81.5% and 90.8%. However, ELISA revealed a high frequency of false negatives, and unacceptably low negative predictive values between 28.6% and 55.4%. The history of poliovirus immunity in the cohort was further investigated by NT. A high level of seropositivity to poliovirus type 1 (PV-1) was found. In cord blood, 83.3% had a NT titre greater than or equal to 4 and 99.0% had a titre greater than or equal to 2. Similarly, by one year of age, 85.7% had a titre greater than or equal to 4 and 90.5% had a titre greater than or equal to 2. Seropositivity to PV-2 and PV-3 were slightly lower, ie 80.8% of children had a PV-2 titre greater than or equal to 4 and 75.4% had a PV-3 titre greater than or equal to 4. As for other developing areas, poliomyelitis eradication in Gaza will come about when universal vaccination fills all 'immunity gaps' and improved sanitation and housing reduces the endemicity of wild polioviruses.

Antibodies, Viral↗