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1.
J Dairy Sci ; 104(9): 9999-10009, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34099298

ABSTRACT

Although future production of dairy goats is influenced by kid-rearing practices, little is known regarding which practices maximize kid growth, welfare, and future production success. The objectives of this survey study were to (1) identify common rearing practices of Canadian commercial dairy goat farms and evaluate their associations with 6 farm performance indicators and (2) determine if farms could be grouped by management style on the basis of the 6 performance indicators and compare rearing practices common across the different groups. A survey was sent by post or electronic media to reach dairy goat producers across Canada. The questionnaire contained 70 questions on the following areas of kid rearing: kidding management, care of newborn, colostrum management, milk and solid feeding in the preweaning period, health management, disbudding, housing conditions, weaning strategies, record keeping and growth monitoring, and farm performance data. Performance indicators, calculated on self-reported data, were 305-d milk production, preweaning mortality rate, diarrhea and respiratory disease prevalence, average daily gain from birth to weaning, herd milk production, and replacement rate. A total of 175 questionnaires were returned. After applying inclusion criteria, including herd size (≥40 goats) and completeness of surveys, 104 respondents from Ontario (n = 72, 69%), Québec (n = 23, 22%), and the Western provinces (n = 9, 9%) were retained for analysis, representing 29% of all Canadian producers. Farm sizes ranged from 42 to 2,500 (median = 190) goats. A large amount of variation in rearing practices and farm performance was found between farms. Colostrum and milk feeding management were found to be associated with all performance indicators except for kid respiratory disease prevalence, with timing of colostrum delivery and feeding method accounting for most the associations within each of the 2 areas. Replacement rate was mostly affected by whether or not kids were reared with their dam. Herds surveyed in the study could successfully be divided into 3 distinct groups (production-focused, longevity-focused, and low performance), representing different management styles on the basis of farm self-reported performance levels. Rearing practices found to be associated with higher farm performance could be targeted by advisory services to help improve management practices on Canadian dairy goat farms.


Subject(s)
Dairying , Goats , Animals , Farms , Female , Ontario , Pregnancy , Self Report , Surveys and Questionnaires
2.
J Anim Sci ; 93(11): 5355-66, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26641055

ABSTRACT

Microbial protein synthesis in the rumen would be optimized when dietary carbohydrates and proteins have synchronized rates and extent of degradation. The aim of this study was to evaluate the effect of varying ruminal degradation rate of energy and nitrogen sources on intake, nitrogen balance, microbial protein yield, and kinetics of nutrients in the rumen of growing kids. Eight Boer goats (38.2 ± 3.0 kg) were used. The treatments were arranged in a split-plot Latin square design with grain sources (barley or corn) forming the main plots (squares). Grain processing methods and levels of protein degradability formed the subplots in a 2 × 2 factorial arrangement for a total of 8 dietary treatments. The grain processing method was rolling for barley and cracking for corn. Levels of protein degradability were obtained by feeding untreated soybean meal (SBM) or heat-treated soybean meal (HSBM). Each experimental period lasted 21 d, consisting of a 10-d adaptation period, a 7-d digestibility determination period, and a 4-d rumen evacuation and sampling period. Kids fed with corn had higher purine derivatives (PD) excretion when coupled with SBM compared with HSBM and the opposite occurred with barley-fed kids ( ≤ 0.01). Unprocessed grain offered with SBM led to higher PD excretion than with HSBM whereas protein degradability had no effect when processed grain was fed ( ≤ 0.03). Results of the current experiment with high-concentrate diets showed that microbial N synthesis could be maximized in goat kids by combining slowly fermented grains (corn or unprocessed grains) with a highly degradable protein supplement (SBM). With barley, a more rapidly fermented grain, a greater microbial N synthesis was observed when supplementing a low-degradable protein (HSBM).


Subject(s)
Animal Feed/analysis , Goats/physiology , Hordeum/chemistry , Protein Biosynthesis/drug effects , Rumen/drug effects , Zea mays/chemistry , Animal Nutritional Physiological Phenomena , Animals , Diet/veterinary , Dietary Carbohydrates/pharmacology , Dietary Supplements/analysis , Digestion/drug effects , Fermentation , Gastrointestinal Motility/drug effects , Goats/microbiology , Hordeum/metabolism , Kinetics , Nitrogen/metabolism , Rumen/microbiology , Rumen/physiology , Glycine max/metabolism , Zea mays/metabolism
3.
Animal ; 4(6): 944-50, 2010 Jun.
Article in English | MEDLINE | ID: mdl-22444267

ABSTRACT

The aim of this study was to determine the effects of restricted feeding before puberty on growth performance and mammary gland development in replacement ewe lambs. At weaning, 72 Dorset ewe lambs were assigned to one of the three diets: an ad libitum control diet with medium-quality forage (MQF; diet A-MQF); a restricted diet with the same forage as A, but less feed concentrate (diet R-MQF); or a high-quality forage (HQF) diet (diet F-HQF). The quantity of concentrate offered to the group R-MQF and F-HQF ewe lambs was adjusted to obtain 70% of the control ewe lambs' growth rate. The diets were offered for 75 days after weaning to cover the allometric phase of mammary gland development. During this period, average daily gain (ADG) was 223 and 229 g/day for groups R-MQF and F-HQF, respectively, compared to 305 g/day for group A-MQF (P < 0.0001). At the end of this period, 28 ewe lambs were slaughtered and their mammary gland was collected. Parenchymal fresh tissue weight tended to be higher for groups R-MQF and F-HQF compared to group A-MQF (P = 0.09). Stroma weight was greater (P < 0.05) for the group A-MQF ewe lambs than for those in the other treatments. Total DNA and total protein in parenchymal tissue tended to be greater for groups R-MQF and F-HQF (P = 0.09 and P = 0.07, respectively). Dry fat-free tissue was greater for groups R-MQF and F-HQF (P < 0.05). The remaining ewe lambs were fed the same haylage and barley diet until their first lambing. During this period, compensatory growth was observed. ADG was greater (P < 0.01) for groups R-MQF and F-HQF than for group A-MQF, and feed conversion was improved (P < 0.01) for groups R-MQF and F-HQF compared with the control, whereas the dry matter intake was similar for all groups. Live body weight, loin eye depth and backfat depth at breeding and around lambing were similar for all groups. The results of this study suggest that restricted feeding before puberty improves mammary gland development without compromising growth performance in ewe lambs.

4.
Animal ; 4(12): 1997-2003, 2010 Dec.
Article in English | MEDLINE | ID: mdl-22445373

ABSTRACT

The aim of this study was to determine the effects of restricted feeding before puberty on reproduction, lactation and offspring growth performance in replacement ewe lambs over two breeding seasons. At weaning, 41 Dorset ewe lambs were assigned to one of three diets: an ad libitum control diet with medium-quality forage (MQF; 13.3% crude protein (CP), 1.81 Mcal metabolizable energy per kg, 42.8% ADF; diet A-MQF); a restricted diet with the same forage as A but less feed concentrate (diet R-MQF); or a high-quality forage (HQF) diet (14.8% CP, 2.15 Mcal ME/kg, 34.7% ADF; diet F-HQF). The quantity of concentrate offered to the group R-MQF and F-HQF ewe lambs was adjusted to obtain 70% of the control ewe lambs' growth rate. The diets were offered for 75 days following weaning to cover the allometric phase of mammary gland development. Prepubertal restriction did not affect (P > 0.10) the gestation rate, number of lambs born or the body weight and body condition score of ewes at lambing or at the end of lactation. Ewes from groups R-MQF and F-HQF tended to produce more milk during their first lactation compared to those from group A-MQF (P = 0.07). During the second lactation, groups R-MQF and F-HQF had better standardized milk production than group A-MQF (P < 0.05), and group R-MQF produced more milk than group F-HQF (P < 0.05). Milk fat and protein content were not affected by treatments (P > 0.10) Fat and protein yield were affected by treatments only at the second lactation (P < 0.10 and P < 0.05, respectively). Lamb birth and weaning weights were not affected by prepubertal restriction of feeding in their mother (P > 0.10). However, the average daily gain of second breeding season lambs was higher for the R-MQF group than the F-HQF group (P < 0.05), and a similar trend was observed for total gain (P < 0.10). Restricted feeding before puberty does not impair future reproductive performance; however, it has a positive impact on lactation and on lambs' growth performance.

5.
Nat Mater ; 1(3): 185-9, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12618808

ABSTRACT

The alloy GaN(x) As(1-x) (with x typically less than 0.05) is a novel semiconductor that has many interesting electronic properties because of the nitrogen-induced dramatic modifications of the conduction band structure of the host material (GaAs). Here we demonstrate the existence of an entirely new effect in the GaN(x) As(1-x) alloy system in which the Si donor in the substitututional Ga site (Si(Ga)) and the isovalent atom N in the As sublattice (N(As)) passivate each other's electronic activity. This mutual passivation occurs in Si-doped GaN(x) As(1-x) through the formation of nearest-neighbour Si(Ga) -N(As) pairs and is thermally stable up to 950 degrees C. Consequently, Si doping in GaN(x) As(1-x) under equilibrium conditions results in a highly resistive GaN(x) As(1-x) layer with the fundamental bandgap governed by a net 'active' N, roughly equal to the total N content minus the Si concentration. Such mutual passivation is expected to be a general phenomenon for electrically active dopants and localized state impurities that can form nearest-neighbour pairs.


Subject(s)
Alloys/chemistry , Arsenic/chemistry , Arsenicals/chemical synthesis , Crystallization/methods , Gallium/chemistry , Materials Testing/methods , Nitrogen/chemistry , Semiconductors , Silicon/chemistry , Crystallography/methods , Electric Impedance , Sensitivity and Specificity , Temperature
6.
J Urol ; 150(4): 1218-21, 1993 Oct.
Article in English | MEDLINE | ID: mdl-8371396

ABSTRACT

We performed laparoscopically assisted percutaneous renal biopsy on 4 patients with azotemia or renal dysfunction who were believed to be unsuitable candidates for percutaneous renal biopsy. Tissue adequate for diagnosis was obtained in all 4 cases. Complications included subcutaneous emphysema in 1 patient and a small splenic capsular tear in 1, which was managed laparoscopically and did not require transfusion. Bleeding from the renal biopsy occurred in 1 patient and was easily managed laparoscopically. We recommend laparoscopically assisted percutaneous renal biopsy as an alternative method of renal biopsy in patients who can tolerate general anesthesia and who are not candidates for percutaneous renal biopsy.


Subject(s)
Biopsy, Needle/methods , Kidney/pathology , Laparoscopy , Adult , Aged , Biopsy, Needle/adverse effects , Female , Hemorrhage/etiology , Humans , Kidney/abnormalities , Male , Middle Aged , Obesity/complications , Renal Insufficiency/pathology , Spleen/injuries , Subcutaneous Emphysema/etiology , Uremia/pathology
7.
Adv Perit Dial ; 9: 169-72, 1993.
Article in English | MEDLINE | ID: mdl-8105916

ABSTRACT

An obese 48-year-old diabetic woman with end-stage renal disease (ESRD) on continuous ambulatory peritoneal dialysis (CAPD) developed symptomatic cholelithiasis within 2 weeks of initiating CAPD. She was not a good risk for either open cholecystectomy or postoperative hemodialysis, and the relatively noninvasive surgical approach of laparoscopic cholecystectomy was considered to minimize postoperative morbidity and to allow the patient to resume her CAPD treatments after a short postoperative recess from dialysis altogether. The patient tolerated the procedure well with no complications. She resumed routine CAPD on her third postoperative day.


Subject(s)
Cholecystectomy, Laparoscopic , Diabetes Mellitus, Type 1/complications , Peritoneal Dialysis, Continuous Ambulatory , Cholecystectomy, Laparoscopic/methods , Cholelithiasis/complications , Cholelithiasis/surgery , Diabetes Complications , Diabetic Nephropathies/complications , Female , Humans , Kidney Failure, Chronic/etiology , Kidney Failure, Chronic/therapy , Middle Aged , Obesity , Risk Factors
8.
Eur J Appl Physiol Occup Physiol ; 65(6): 485-91, 1992.
Article in English | MEDLINE | ID: mdl-1483435

ABSTRACT

Twenty-one experienced runners were studied before, during and immediately after a marathon race to ascertain whether either depletion of energy substrate or rise in body temperature, or both, contribute to late-race slowing of running pace. Seven runners drank a glucose/electrolyte (GE) solution ad libitum (Na+ 21 mmol l-1, K+ 2.5 mmol l-1, Cl- 17 mmol l-1, PO4(2-) 6 mmol l-1, glucose 28 mmol l-1) throughout the race; 6 drank water and 8 drank the GE solution diluted 1:1 with water. Although average running speeds for the three groups were not significantly different during the first two-thirds (29 km) of the race, rectal temperature was significantly higher (P < 0.05) and reduction of plasma volume was greater (P < 0.05) in runners who replaced sweat losses with water. During the last one-third of the race, the average running pace of the water-replacement group slowed by 37.2%; the pace slowed by 27.9% in the 8 runners who replaced their sweat loss with GE diluted 1:1 with water (1/2 GE) and 18.2% in runners who replaced fluid loss with full-strength solution (GE). Eleven runners (5 in the water group, 4 in the 1/2 GE group and 2 in the GE group) lapsed into a walk/run/walk pace during the last 6 miles of the race. Ten of these had a rectal temperature of 39 degrees C or greater after 29 km of running, and plasma volume in these runners was reduced by more than 10%.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Exercise/physiology , Running , Adult , Blood Glucose/metabolism , Blood Pressure/physiology , Blood Volume/physiology , Body Temperature/physiology , Electrolytes/blood , Female , Humans , Insulin/blood , Male , Sweating/physiology
9.
Psychol Rep ; 68(3 Pt 1): 733-4, 1991 Jun.
Article in English | MEDLINE | ID: mdl-1891533

ABSTRACT

Relationships among fluid intake and dietary-adherence of 29 hemodialysis patients, nurses' attitudes (liking-disliking) toward these patients, and selected nurses' and patients' verbalizations during hemodialysis treatment were explored. No significant associations were found. Nurses may be facilitating positive solutions to all patients' health care problems rather than admonishing those whom they dislike and/or who do not adhere to treatment.


Subject(s)
Attitude of Health Personnel , Kidney Failure, Chronic/psychology , Nurse-Patient Relations , Patient Compliance/psychology , Renal Dialysis/psychology , Adult , Aged , Female , Humans , Kidney Failure, Chronic/nursing , Male , Middle Aged , Renal Dialysis/nursing
10.
Eur J Clin Pharmacol ; 40(6): 613-7, 1991.
Article in English | MEDLINE | ID: mdl-1884744

ABSTRACT

Seven patients undergoing routine thrice weekly haemodialysis for endstage renal failure participated in 12 investigations of dichloroacetate (DCA) pharmacokinetics and pharmacodynamics. DCA doses were 50 mg/kg by i.v. infusion over 30 min. In each investigation single doses were administered to each subject on two consecutive days, one being a day during which the patient was dialyzed. The timing of drug administration, relative to dialysis, was varied to assess the effect of dialysis on the apparent volume of distribution and elimination rate constants of DCA and on its effect on blood glucose and lactate. Dialysis increased the clearance of DCA by approximately 60%, but had no effect on its apparent volume of distribution. Dialysis did not reduce the maximal lactate-lowering effect of DCA, but slightly decreased the duration of this effect. Blood glucose levels were not significantly altered by DCA and no adverse drug effects were observed. We conclude that dialysis increases plasma clearance of DCA, but has little influence on the metabolic effects of the drug when given at 50 mg/kg doses. DCA can safely and effectively be given to hemodialysis patients who may require the drug for treatment of lactic acidosis.


Subject(s)
Dichloroacetic Acid/pharmacokinetics , Kidney Failure, Chronic/metabolism , Renal Dialysis , Adult , Blood Glucose/analysis , Dichloroacetic Acid/administration & dosage , Dichloroacetic Acid/blood , Dichloroacetic Acid/urine , Drug Administration Schedule , Female , Humans , Kidney Failure, Chronic/drug therapy , Lactates/blood , Lactic Acid , Male , Middle Aged
11.
Perit Dial Int ; 11(4): 341-6, 1991.
Article in English | MEDLINE | ID: mdl-1751601

ABSTRACT

This study compared chronic hemodialysis and CAPD patients on several quality of life variables: dietary adherence, self-esteem, hope, wellbeing, marital happiness, perceived control over life, marital status, number of emotional support persons, and participation in social, recreational, and work activities. Statistically significant differences in the quality of life variables due to treatment modality or demographic variables were not found. However, CAPD patients did engage in significantly more social and recreational activity, though not more work activity, than did hemodialysis patients. It is noted that 73% of the CAPD patients were Caucasian and that 72% of the hemodialysis patients were of black origin. Similarly skewed racial compositions in preceding research comparing patients on CAPD and hemodialysis suggest that 1. choice of treatment is occurring on the basis of some set of patient characteristics, or 2. systematic assignment is occurring on the basis of race, sex, and/or education. However, given no significant race/demography differences for variables used in this research, it appears that quality of life across racially different groups of hemodialysis and CAPD patients is comparable.


Subject(s)
Peritoneal Dialysis, Continuous Ambulatory , Quality of Life , Renal Dialysis , Black or African American , Female , Humans , Kidney Failure, Chronic/psychology , Kidney Failure, Chronic/therapy , Male , Middle Aged , Peritoneal Dialysis, Continuous Ambulatory/psychology , Renal Dialysis/psychology , Social Behavior , Socioeconomic Factors
12.
Nephron ; 50(1): 24-7, 1988.
Article in English | MEDLINE | ID: mdl-3173598

ABSTRACT

Twelve postmenopausal women who experienced frequent urinary tract infections were found to have atrophic vaginitis. Four of them who were taking sulfonamide preparations chronically also had an interstitial nephritis manifest by decreasing glomerular filtration rate and eosinophiluria. Treatment consisted of a Betadine douche daily for 1 week, administration of an appropriate nonsulfonamide antibiotic, and institution of estrogen therapy to restore glycogen deposition in the vaginal epithelium and promote return of a normal vaginal pH and bacterial flora. Prior to estrogen therapy, the frequency of infection was four per patient per year. During a follow-up observation period ranging from 2 to 8 years, there have been only four infections in the entire group. When sulfonamides were discontinued in the 4 patients with manifestations of interstitial nephritis, the eosinophiluria cleared, and the glomerular filtration rate increased significantly.


Subject(s)
Menopause , Urinary Tract Infections/prevention & control , Estrogens/therapeutic use , Female , Glomerular Filtration Rate , Humans , Middle Aged , Nephritis, Interstitial/chemically induced , Nephritis, Interstitial/physiopathology , Povidone-Iodine/administration & dosage , Recurrence , Sulfonamides/adverse effects , Therapeutic Irrigation , Urinary Tract Infections/complications , Vaginitis/complications , Vaginitis/drug therapy
13.
Am J Med ; 82(3): 427-38, 1987 Mar.
Article in English | MEDLINE | ID: mdl-3548346

ABSTRACT

Eleven patients with well-documented hepatorenal syndrome were studied by measurement of blood volume, glomerular filtration rate, renal plasma flow, plasma aldosterone concentration, renin substrate concentration, and plasma renin activity. They were then given 750 ml of stored plasma, 750 ml of fresh frozen plasma, and then an infusion of angiotensin II, in random order on successive days. Infusion of fresh frozen plasma improved function more than did stored plasma and in addition returned a very low filtration fraction toward normal. Angiotensin II infusion increased filtration fraction, but decreased glomerular filtration rate, renal plasma flow, and urine flow sharply. Patients were then given a daily infusion of 1,000 ml of fresh frozen plasma for seven to 18 days to expand the blood volume to supranormal levels as assayed by serial measurement of blood volume. Plasma aldosterone levels decreased to a normal range, glomerular filtration rate and renal plasma flow both increased, and urinary excretion of sodium and potassium both returned toward normal. The effect of intraperitoneal pressure was then studied by measuring glomerular filtration rate, renal plasma flow, pressure in the vena cava, hepatic vein free flow, and hepatic vein wedged pressure before, during, and after paracentesis to reduce the intraperitoneal pressure from 30 to 40 cm H2O to 12 to 17 cm H2O. Venous pressures moved parallel to ascitic fluid pressures, and glomerular filtration rate, renal plasma flow, and urine flow all improved sharply; then, as ascitic fluid continued to form, reducing vascular volume, urine flow, glomerular filtration rate, and renal plasma flow all decreased slowly. Six patients then underwent placement of a LeVeen shunt. Improvement in glomerular filtration rate and renal plasma flow and clinical condition was dramatic. During postoperative observation of up to two years, progressive improvement in hepatic function has occurred.


Subject(s)
Blood Volume , Hepatorenal Syndrome/physiopathology , Kidney Diseases/physiopathology , Kidney/physiopathology , Liver/physiopathology , Peritoneal Cavity/physiopathology , Angiotensin II/therapeutic use , Ascites/physiopathology , Blood Transfusion , Combined Modality Therapy , Female , Hepatorenal Syndrome/therapy , Humans , Male , Peritoneovenous Shunt , Plasma , Pressure , Renin/blood , Time Factors
14.
Am J Kidney Dis ; 7(6): 471-6, 1986 Jun.
Article in English | MEDLINE | ID: mdl-3717154

ABSTRACT

Povidone-iodine is frequently used as an antiseptic in patients on chronic dialysis. In order to determine if the use of povidone-iodine affects thyroid function in these patients, we measured serum iodine and thyroid hormone levels in dialysis patients prior to and following discontinuation of topical povidone-iodine antiseptics. Serum inorganic iodine levels were elevated initially in nearly 90% of the patients (19 on hemodialysis, 12 on continuous ambulatory peritoneal dialysis [CAPD]). Following discontinuation of povidone-iodine, iodine levels over a 3-month period decreased modestly in patients on CAPD (n = 5) and were unchanged in patients on hemodialysis (n = 5). Total and free thyroxine levels were frequently low but did not correlate with protein-bound or inorganic iodine levels and did not change after discontinuation of povidone-iodine. Thyrotropin levels correlated significantly (r = .62, P less than .01) with inorganic iodine levels in patients on hemodialysis, but not for patients on CAPD. We conclude that abnormal thyroid function tests are common in dialysis patients but are not related to iodine retention or to the routine use of topical povidone-iodine-containing antiseptics.


Subject(s)
Hypothyroidism/chemically induced , Iodine/blood , Peritoneal Dialysis, Continuous Ambulatory , Povidone-Iodine/adverse effects , Povidone/analogs & derivatives , Renal Dialysis , Adult , Aged , Female , Humans , Kidney Diseases/blood , Kidney Diseases/therapy , Male , Middle Aged , Thyroid Function Tests , Thyroid Hormones/blood , Thyrotropin/blood , Thyroxine/blood
15.
Arch Intern Med ; 146(4): 737-41, 1986 Apr.
Article in English | MEDLINE | ID: mdl-3963956

ABSTRACT

Thirteen adult patients with nephrotic syndrome resistant to corticosteroid administration were treated with azathioprine daily for four years. Progressive improvement occurred in all 13 patients so that they were in complete remission after one to three years. The onset of apparent improvement was earlier and the rate of progressive improvement more rapid in patients who had selective proteinuria before therapy than in those whose proteinuria was nonselective. One patient who stopped therapy after 20 months suffered relapse but again responded when azathioprine treatment was restarted. Observation after the four-year therapeutic period ranges from three to 15 years; there have been no relapses during this time.


Subject(s)
Azathioprine/therapeutic use , Nephrosis, Lipoid/drug therapy , Nephrotic Syndrome/drug therapy , Prednisone/therapeutic use , Adolescent , Adult , Aged , Child , Child, Preschool , Creatinine/blood , Creatinine/urine , Drug Resistance , Female , Follow-Up Studies , Humans , Male , Middle Aged , Nephrosis, Lipoid/complications , Nephrosis, Lipoid/metabolism , Nephrotic Syndrome/etiology , Nephrotic Syndrome/metabolism , Proteinuria/drug therapy , Recurrence , Time Factors
16.
J Clin Invest ; 77(3): 750-6, 1986 Mar.
Article in English | MEDLINE | ID: mdl-3005363

ABSTRACT

Human platelets that were preincubated with porcine elastase aggregated spontaneously upon the addition of fibrinogen. Maximal aggregation to fibrinogen was observed with platelets pretreated with an elastase concentration of 111 micrograms/ml, and half-maximal aggregation occurred after treatment with 11 micrograms/ml elastase. Binding of radiolabeled fibrinogen to elastase-treated platelets was specific, saturable, and showed a single class of 48,400 +/- 9,697 fibrinogen-binding sites per platelet with a dissociation constant of 6.30 +/- 1.48 X 10(-7) M. ATP, apyrase, and the stimulators of platelet adenylate cyclase forskolin, prostaglandin E1, prostacyclin, and N6, 2'-O-dibutyryl cyclic AMP did not inhibit the fibrinogen-induced aggregation of elastase-treated platelets. EDTA completely blocked the initiation of aggregation and reversed the fibrinogen-induced aggregation of elastase-treated platelets. Monoclonal and polyclonal antibodies directed against glycoproteins (GP) IIb and IIIa completely blocked the fibrinogen-induced aggregation of elastase-treated platelets. Immunoprecipitates with these antibodies obtained from detergent extracts of surface-radiolabeled, intact, and elastase-treated platelets contained the glycoproteins IIb and IIIa. We conclude that surface proteolysis by low concentrations of elastase can expose fibrinogen-binding sites associated with GPIIb and GPIIIa on the platelet surface, resulting in spontaneous aggregation upon the addition of fibrinogen. These findings may be relevant to hemostatic changes observed in patients with increased levels of circulating elastase.


Subject(s)
Blood Platelets/metabolism , Fibrinogen/metabolism , Glycoproteins/metabolism , Membrane Proteins/metabolism , Pancreatic Elastase/metabolism , Platelet Aggregation , Receptors, Cell Surface/metabolism , Adenosine Triphosphate/metabolism , Cations, Divalent/pharmacology , Humans , Platelet Aggregation/drug effects , Platelet Membrane Glycoproteins
17.
Am J Med ; 77(5): 785-90, 1984 Nov.
Article in English | MEDLINE | ID: mdl-6496532

ABSTRACT

One hundred five patients with established diastolic hypertension were enrolled in an exercise program to examine the effect of aerobic conditioning on blood pressure. In four patients, the decrease in mean blood pressure was less than 5 mm Hg; in all others, there was a significant decline in arterial blood pressure. In 58 patients who were not taking drug medication in the pre-exercise period, mean blood pressure decreased by 15 mm Hg. Of 47 patients receiving drug therapy during the pre-exercise period, 24 were able to discontinue all medication. Mean blood pressure in this group fell from 116.9 +/- 6.5 mm Hg to 97.2 +/- 9.2 mm Hg as a result of exercise. In patients still taking antihypertensive drugs, mean pressure decreased from 120.9 +/- 28.8 mm Hg to 104.4 +/- 17.9 mm Hg after three months of exercise. It is concluded that in patients physically and emotionally able to exercise, a significant decline in blood pressure can be achieved.


Subject(s)
Exercise Therapy , Hypertension/therapy , Adult , Aged , Female , Humans , Hypertension/drug therapy , Hypertension/physiopathology , Male , Middle Aged
18.
Med Sci Sports Exerc ; 16(3): 263-8, 1984 Jun.
Article in English | MEDLINE | ID: mdl-6748924

ABSTRACT

Increased concentration of red blood cell 2,3-diphosphoglycerate (RBC 2,3-DPG) shifts the hemoglobin-oxygen dissociation curve to the right, thus theoretically allowing better oxygenation of tissues. To determine whether such a shift is physiologically significant, we investigated the effects of oral phosphate loading on several parameters including plasma phosphate concentration, RBC 2,3-DPG, hematocrit and hemoglobin concentration, maximal oxygen uptake (VO2max), and degree of lactic acidemia in 10 well-trained distance runners. After control determinations were made, either a phosphate load or a placebo was given for 3 d before the athlete was restudied. A placebo and two phosphate-loading studies were performed at weekly intervals, followed by 2 wk of rest and another post-intervention control study. Blood samples for control values were drawn before and after a standard warm-up period, after treadmill exercise at a 10% grade, and at the completion of the VO2 determination. After oral phosphate loading there was a significant increase in serum phosphate and RBC 2,3-DPG. Maximal oxygen uptake was significantly increased and correlated with the rise in RBC 2,3-DPG (r = 0.81). The increase in blood lactate after exercise on the 10% grade was attenuated during sessions which followed phosphate loading.


Subject(s)
Diphosphoglyceric Acids/blood , Oxygen Consumption/drug effects , Phosphates/pharmacology , Physical Exertion , 2,3-Diphosphoglycerate , Erythrocytes , Humans , Lactates/metabolism , Lactic Acid , Male
20.
J Urol ; 129(4): 816-7, 1983 Apr.
Article in English | MEDLINE | ID: mdl-6341625

ABSTRACT

A patient is described who presented with late ureteral necrosis following renal transplantation, a complication that usually is seen in the early perioperative period. The patient was anuric with azotemia and a high serum creatinine. Response to surgical correction of ureteral obstruction was excellent and renal function returned to normal within 6 days postoperatively.


Subject(s)
Creatinine/blood , Kidney Transplantation , Uremia/diagnosis , Ureteral Obstruction/diagnosis , Adult , Female , Humans , Postoperative Complications , Uremia/blood , Uremia/etiology , Ureteral Obstruction/blood , Ureteral Obstruction/etiology
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