PubMed Health⌕ Search

Biomedical subjects

J Greco

Publications and source records attributed to J Greco.

17 recordsLinked to original sources
PubMed1990

The circadian rhythm of the N-terminus and C-terminus of the atrial natriuretic factor prohormone.

Circadian variation in the circulating concentrations of the N-terminal and C-terminal portions of the atrial natriuretic factor prohormone (pro ANF) was evaluated in 8 men, ages 41-47, who have been followed for 19 years with respect to circadian variation in physiological variables including blood pressure and clinical chemistries. The N-terminus of the ANF prohormone contains two peptides consisting of amino acids 1-30 and 31-67 while the C-terminus contains 1 peptide (amino acids 99-126) of this 126 amino acid prohormone which lower blood pressure and have natriuretic properties. To determine if either the N-terminus and/or the C-terminus of the prohormone have a circadian variation in their circulating plasma concentrations these 8 men had blood samples obtained for radiommunoassay every 3 hr during a 24-hr period. Three radiommunoassays which immunologically recognize (1) the whole N-terminus (i.e. amino acids 1-98), (2) the midportion of the N-terminus (amino acids 31-67) and (3) the C-terminus (amino acids 99-126) of the ANF prohormone were utilized. The whole N-terminus, the midportion of the N-terminus which circulates after being proteolytically cleaved from the rest of the N-terminus, and the C-terminus each had a peak circulating concentration between 0400 and 0700 which were significantly (P less than 0.001) higher than their concentrations at any other time throughout the 24-hr period.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Circadian distribution of proteins in urine from healthy young men.

Urine samples were collected at 3-hr intervals over a single 24-hr period from each of seven clinically healthy men who ranged in age from 21-25 years. Urines at each collection time were subsequently pooled using 20% of each volume and serially dialyzed against ammonium-barbituric acid buffer (pH 7.35 +/- 0.02), using a cellulose membrane permeable to compounds of less than 12,000-14,000 molecular weight (mw). When the dialyzed portions were then analyzed for total proteins, the sum of proteins in eight pools amounted to 74 mg. A 1 ml aliquot of each pool, representing approximately 50 micrograms of proteins, was concentrated and reconstituted. Approximately 20 micrograms of reconstituted proteins were then subjected to polyacrylamide gel electrophoresis. The stained gel was then scanned by laser densitometry and planimetry. Each aliquot revealed eight segments as identified by Coomassie and silver staining. Their molecular weights, estimated by extrapolation from concurrently run protein standards, and their total protein amounts were: 116,000 mw (9.44 mg), 91,000 mw (3.3 mg), 68,000 mw (11.58 mg), 53,000 mw (2.58 mg), 43,000 mw (9.12 mg), 32,000 mw (7.13 mg), 24,000 mw (4.52 mg) and 20,000 mw (5.27 mg). A statistically significant rhythm (P = 0.022 from ANOVA and 0.011 from Single Cosinor) was found for the excretion of total proteins, with an acrophase in the afternoon (1537) for these diurnally-active subjects.

Adult↗
PubMed1990

Reference values for circadian rhythms of 98 variables in clinically healthy men in the fifth decade of life.

Nine clinically healthy men, 41-47 yr of age, served as subjects in a 24-hr study conducted at the Edward Hines Jr Veterans Administration Hospital in the Chicago area in May 1988. Physiologic measurements, and blood and urine samples were collected at 3-hr intervals over a single 24-hr period beginning at 1900. The number of variables measured or calculated (total = 98) included: 6 vital signs (oral temperature, pulse, blood- and intraocular pressures); 16 in whole blood (counts and differentials); 50 in serum (SMAC-24, lipids, hormones, electrophoresis of LDH and proteins); and 26 in urine (solids, proteins, creatinine, catecholamines, melatonin, cortisol, electrolytes and metals). Data were analyzed for time effect by analysis of variance (ANOVA) and for circadian rhythm by single cosinor. Individual rhythm characteristics for each variable were summarized for the group by population mean cosinor. The vast majority of variables revealed statistically significant within-day changes in values as validated by one-way ANOVA. All vital signs (except for intraocular pressures) and all serum hormones displayed a prominent circadian rhythm for the group, as did most variables in whole blood, while only about half of the variables in urine demonstrated a significant group rhythm. The results obtained are meant to: (a) document the circadian time structure; and (b) serve as reference values for circadian rhythm characteristics (range of change, mesor, amplitude and acrophase) for a defined group of individuals: clinically-healthy adult men in the prime of life.

Adult↗
PubMed1990

Circadian reference data for men in fifth decade of life.

These results are meant to serve as chrono-biologically-defined reference values for healthy adult men in their fifth decade of life. A thorough statistical analysis of these data is being prepared for presentation elsewhere. A rigorous comparison with results obtained when these same men were in their 20's and again in their 30's may help us to document the kinds and extent of changes in circadian rhythm characteristics (MESOR, amplitude and/or acrophase) which may occur with aging.

Adult↗
PubMed1988

Ten-year-replicated circadian profiles for 36 physiological, serological and urinary variables in healthy men.

At 3-hr intervals over a 24-hr span, 36 systemic, serologic and urinary variables were examined in 7 men in their mid 20's in the Spring of 1969, and again in the same 7 men in the Spring of 1979 under a similar chronobiologic protocol, using the same chemical and numerical analytical procedures. The variables examined for rhythms by cosinor were: vital signs--blood pressure (systolic, diastolic, pulse pressure and mean arterial pressure), heart rate, intraocular pressure (left and right), oral temperature; serum components--albumin, albumin/globulin ratio, total bilirubin, calcium, carbon dioxide, chlorides, bilirubin, cholesterol, globulin, glucose, potassium, sodium, sodium/potassium ratio, transaminase, triglycerides, total protein, urea nitrogen; and urine components--calcium, calcium/magnesium ratio, creatinine, magnesium, pH, potassium, sodium, sodium/potassium ratio, urea clearance, urea nitrogen, volume and zinc. Although all subjects appeared clinically healthy in 1969 and in 1979, certain inter-study differences were observed in a number of rhythm parameters of different variables. Statistically significant increases in mesor for the group as a whole were observed for serum Ca, cholesterol, Cl, CO2, K, Na, and while statistically significant mesor decreases for a group as a whole were noted in serum glucose and transaminase. Statistically significant increases in amplitude for the group as a whole were observed in serum chloride and urinary Na/K ratio, while statistically significant decreases were observed in amplitude for blood pressure, heart rate, serum albumin, A/G ratio, globulin, glucose, protein, sodium and transaminase.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Effective long-term suppression of pituitary-gonadal axis in prostatic cancer by Zoladex (ICI 118,630).

Eleven patients with prostatic cancer maintained on monthly depot Zoladex (ICI 118,630) from 20 to 23.5 months are described. All are in clinical remission. Castrate levels of testosterone are maintained, and low levels of LH and FSH were observed. Contrary to a prior report, persistent blockage of the pituitary-gonadal axis is achieved and maintained with no detectable adverse side effects.

Buserelin↗
PubMed1987

Circadian variations in eleven radioimmunoassay variables in the serum of clinically healthy men.

Radioimmunoassay studies were conducted on 13 clinically healthy male subjects. Ten ranged in age between 23 and 44 years, two were age 51, and one was age 58. Blood samples were collected at 3-hr intervals over a period of 27 hr. Each serum sample was analyzed for the following hormones: insulin, gastrin, melatonin, prolactin, triiodothyronine (uptake), thyroid-stimulating hormone, triiodothyronine, thyroxine, luteinizing hormone, growth hormone, and follicle-stimulating hormone. Group data for each hormone were fitted to a 24-hr cosine curve. A statistically significant fit to this curve was evident in the six italicized variables. Those that did not yield a statistically significant fit frequently revealed a statistically significant variation along the 27-hr span. Chronogram and cosinor plots are presented.

Adult↗
PubMed1986

Reversal by indomethacin of renal effects of dopamine in subjects with normal renal function.

In five subjects with normal renal function, intravenous dopamine, at a rate of 6 ug/kg/min, produces a renal vasodilation, increase in Na excretion and reduction in urinary osmolality, without modification in glomerular filtration rate. These effects were reversed by intravenous indomethacin (2 mg/kg), suggesting that the renal effects of dopamine might depend on normal prostaglandins production.

Adult↗
PubMed1986

Assessment of HBV replicative status by receptors for polymerized human albumin.

Receptors for polymerized human albumin (pHSA-r) are expressed on HBsAg in larger numbers during complete viral replication. We have evaluated the usefulness of pHSA-r as a marker of high-level infection by a comparison with serum HBeAg, liver HBcAg and serum HBV-DNA. One-hundred-and-fifty-seven patients with HBsAg positive chronic liver disease were tested for HBeAg and pHSA-r titre. In 73 of them liver HBcAg was tested by immunofluorescence, while in the remaining 84 serum HBV-DNA was determined. Seventy-three subjects were HBeAg positive, 20/73 were HBcAg positive, and 60/84 had circulating HBV-DNA. The best cut-off for pHSA-r was found at 1:204,800 (sensitivity of 67.6% and specificity of 95.7% in detecting viral replication). At this cut-off the concordance rate between pHSA-r and viral replication (as assessed by HBV-DNA or liver HBcAg) was 83%, a figure similar to that of HBeAg (88%). Three HBeAg negative subjects who were actually complete replicators were identified by the pHSA-r test.

Carrier State↗
PubMed1985

Application of dimethyl sulfoxide to skin of white and hairless mice.

Dimethyl sulfoxide (DMSO) was applied to a 2-cm2 area on the backs of four groups of mice for a 5-min period each day, 5 days per week, for the designated periods: groups I and II--six hairless albino mice (hrhr, c/c) per group--were treated for 8 weeks; group III--three hairless albino mice (hrhr, c/c)--were treated for 4 weeks; group IV--three white mice (ICR Swiss)--were treated for 8 weeks. A group of six untreated hairless albino mice (hrhr, c/c) (group V) functioned as controls for groups I, II and III, and a group of three white mice (ICR Swiss) (group VI) served as controls for group IV. Except for DMSO applications, controls were handled and treated in the same way as the experimental groups. At the end of the experimental periods, the claws of all appendages were removed, measured and average lengths were determined. The claws of group I and group II hairless albino mice were, on average, 2.4-fold longer than the claws of the control hairless albino mice, a significant increase (p less than 0.01) in the average claw length. There was no significant difference in the lengths of the claws of the group III mice after 4 weeks of DMSO application. The claws of group IV (ICR Swiss mice) were, on average, 1.2-fold longer than the claws of the control white mice, representing a significant increase (p less than 0.02) in claw length after 8 weeks of DMSO application.

Administration, Topical↗
PubMed1985

Polyalbumin receptors, hepatitis B surface antigen (HBsAg), and HBsAg/IgM complexes in HBsAg positive patients with and without delta superinfection.

Receptors for polymerized human albumin are found at high titres during high-level hepatitis B virus (HBV) replication and in small amounts in chronic low-level infection. Complexes between hepatitis B surface antigen (HBsAg) and IgM without specificity for HbsAg are expressed in a pattern similar to that of receptors. Anti-albumin antibodies could be involved in their formation. Delta infection depresses the synthesis of gene products of HBV. To assess whether delta modifies the expression of receptors on HBsAg and the level of HBsAg/IgM complexes, and if anti-albumin antibodies are actually part of the complex, we tested sera from 86 subjects with acute and chronic HBV infection. Our findings show that the amounts of circulating receptors and HBsAg/IgM are proportional to the concentration of HBsAg and thus probably to the degree of viral replication. We did not find any correlation between circulating anti-albumin antibodies of the IgM class and HBsAg/IgM complexes. Delta infection depresses HBsAg synthesis and causes a related decrease in receptors and HBsAg/IgM titres if superimposed on the more active stage of HBV infection. When HBsAg, receptors, and HBsAg/IgM are at low levels, no further depression is caused by delta infection. HBsAg/IgM titre is not enhanced by presence of anti-delta antibodies, thus excluding a role of the latter in forming these complexes.

Acute Disease↗
PubMed1979

Instrumental analysis of trace elements in thumbnails of human subjects.

Human thumbnails were analyzed for trace elements by instrumental analysis using thermal neutron activation technique. The average concentration of metals studied in clinically symptom-free adult female and male subjects were: zinc, 184 vs. 153 ppm; chromium, 6.8 vs. 4.2; selenium, 0.9 vs. 0.6; gold, 2.6 vs. 0.4; mercury, 1.9 vs. 0.4; silver, 0.7 vs. 0.3; cobalt, 0.07 vs. 0.04. A summary of literature reported concentration of metals in human nail is also presented.

Adult↗
PubMed1978

Further study of fibrinogen degradation products in bladder cancer detection.

A new, rapid immunoassay kit for assaying fibrinogen degradation products (FDP) was studied in 56 patients with cancer of the bladder and in 48 control patients. The specificity of the kit was demonstrated with a small number of false positive results. In bladder cancer patients with low-stage, small superficial tumors, FDP was positive in 32.2 per cent. The combination of urinary cytologic examination with FDP increased the accuracy of the positive results to 80 per cent. The rapid FDP test supplements the urinary cytology in the follow-up and detection of early bladder cancer.

Cytodiagnosis↗
PubMed1976

The haemodynamic response to salt and water loading in patients with end-stage renal disease and anephric man.

1. Patients with end-stage renal disease and anephric patients underwent expansion and depletion of body fluids with salt and water. This resulted in four different sequential haemodynamic patterns: (i) no significant increase in blood pressure; (ii) increase in blood pressure associated with a rise in cardiac output and no effect on total peripheral resistance; (iii) increase in cardiac output followed by a rise in blood pressure and total peripheral resistance; (iv) increase in total peripheral resistance and blood pressure without significant changes in cardiac output. 2. It is concluded that an initial rise in cardiac output is not necessary to increase-blood pressure in either anephric man or patients with end-stage renaldisease.

Blood Pressure↗
PubMed1975

Increasing the inotropic effect and toxic dose of digitalis by the administration of antikaliuretic drugs--further evidence for a cardiac effect of diuretic agents.

In prior studies, we have shown that the antikaliuretic drugs, triamterene and amiloride, through a direct cardiac effect reduce the loss of cardiac potassium induced by the administration of digitalis. Since loss of myocardial potassium is thought to underlie digitalis arrhythmias, this study was performed to determine whether triamterene and amiloride also extend the toxic dose and thus the therapeutic effect of digitalis. In twelve dogs, acetylstrophanthidin was infused (100 ug per minute) serially at 2.5-hour intervals. Trimterene (400 mg. in divided doses) was infused before the third acetylstrophanthidin infusion. This extended the dose required to produce a toxic arrhythmia by 110 per cent. In fourteen additional studies, nine dogs received 400 mg. of triamterene prior to the third acetylstrophanthidin infusion and five animals received 100 mg. of amiloride during the same period. In these fourteen studies, not only was the toxic dose of digitalis extended, but its inotropic effect (see article) (common peak developed isovolumic ventricular pressure) was also increased. These studies have demonstrated that through a cardiac effect, by reducing the digitalis-induced loss of cardiac potassium, the potassium-sparing drugs, triameterene and amiloride, extend the toxic dose of digitalis and thus permit txtension of its inotropic activity.

Amiloride↗