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Biomedical subjects

T Joyce

Publications and source records attributed to T Joyce.

At least 55 records · Page 3Linked to original sources

The social and economic correlates of pregnancy resolution among adolescents in New York City, by race and ethnicity: a multivariate analysis.

This study utilizes a data set combining vital records from live birth and induced abortion certificates in New York City in 1984 to examine the correlates of the two outcomes among pregnant adolescents. Four groups totaling 31,207 teenagers were examined: Black non-Latinos (51 per cent), White non-Latinos (17 per cent), Puerto Ricans (25 per cent), and non-Puerto Rican Latinos (8 per cent). Multivariate regressions were fit for each group. Simulations based on the regressions reveal that the proportion of live births plus induced abortions among unmarried 18-year-olds, on Medicaid, with a previous live birth, no previous induced abortions, and nine years of completed schooling was .55 in the case of Puerto Ricans, .34 for non-Puerto Rican Latinos, .60 for Blacks, and .51 for Whites. For nulliparous adolescents of the same age and marital status, with an additional year of schooling, but not on Medicaid, and with a previous induced abortion, the fraction of pregnancies that were terminated rose to .84 in the case of Puerto Ricans, .81 for non-Puerto Rican Latinos, .87 for Blacks, and .96 for Whites. The results suggest that attitudes toward abortion as proxied by previous induced terminations substantially increase the likelihood of aborting as well as narrow the racial and ethnic differences with respect to pregnancy resolution.

Adolescent↗

The demand for health inputs and their impact on the black neonatal mortality rate in the U.S.

Relatively high birth rates among black adolescents and unmarried women as well as inadequate access to medical care are considered primary reasons why the black neonatal mortality rate is almost double that of whites. Using household production theory, this paper examines the determinants of input utilization and estimates the impact of utilization on the survival of black infants across large counties in the U.S. in 1977. The results indicate that expanding the availability of family planning clinics increases the number of teenagers served resulting in a lower neonatal mortality rate. Accessibility to abortion services operates in a similar manner. Moreover, the use of neonatal intensive care, which is strongly related to its availability, is an important determinant of newborn survivability whereas the initiation of early prenatal care is not. Overall, the results suggest that lowering the incidence of low-weight and preterm births among blacks by helping women to avoid an unwanted birth, may be the most cost-effective way of improving black infant health.

Abortion, Induced↗

The impact of induced abortion on black and white birth outcomes in the United States.

This paper examines the impact of induced abortion on birth outcomes by treating abortion as an endogenous input into the production of infant health. To gauge the direct and indirect effects of abortion, three measures of infant health are considered simultaneously: the neonatal mortality rate, the percentage of low-weight births, and the percentage of preterm births. All three are race specific and all pertain to large counties in the United States in 1977. The results suggest that by preventing unwanted births, abortion enhances the survivability of newborns of a given birth weight and improves the distribution of births among high-risk groups.

Abortion, Induced↗

The effects of bupivacaine and chloroprocaine as local anesthetics for epidural anesthesia of fetal heart rate monitoring parameters.

The effects of saline-induced pressure-volume changes in the epidural space, and bupivacaine and chloroprocaine as local anesthetics for epidural anesthesia, on various fetal heart rate monitor parameters were investigated in 34 low-risk women. Epidural space pressure-volume changes, bupivacaine, and chloroprocaine had no effect on the incidence of pathologic periodic fetal heart rate changes, the level of the baseline fetal heart rate, or the level of uterine activity units. Epidural space pressure-volume changes and chloroprocaine did not affect fetal heart rate variability. The use of bupivacaine was associated with a significant increase in fetal heart rate variability

Adult↗

Capillaria plica infection in dogs.

The prevalence, pathologic effects, and treatment of Capillaria plica infection were investigated in two breeding kennels. The prevalence of C plica infection in mature dogs in two kennels (127 dogs) was 76% and 59%. Pups less than 8 months old did not pass C plica eggs in the urine. Age, breed, or sex predilection was not observed in mature dogs. In infected dogs, hematuria, dysuria, and pollakiuria developed without secondary bacterial cystitis. A direct life cycle could not be demonstrated experimentally. Histologically, adult C plica were seen in the submucosa of the bladder and ureter, where they induced a mild inflammatory reaction and submucosal edema.

Animals↗

Characterization of renal defects in dogs with a syndrome similar to the Fanconi syndrome in man.

Ten adult dogs with multiple spontaneous defects of renal tubular reabsorption were studied. Clinical signs included polydipsia, polyuria, and glycosuria for 2 to 12 months. Eight of the dogs were Basenjis. Urinalyses revealed hyposthenuria, glycosuria, and amino aciduria in most dogs. Renal function was normal in 5 dogs and slightly reduced in the remainder. Moderate metabolic acidosis had developed in 3 dogs. Renal clearance studies revealed reduced tubular reabsorption of glucose, phosphate, sodium, potassium, and uric acid. Abnormal glucose tubular maximal curves were found. Results of oral glucose tolerance tests were normal. Two patterns of abnormal amino aciduria were evident: generalized amino aciduria and a pattern similar to that of cystinuria in dogs. Radiography of long bones and bone densitometry did not reveal any skeletal abnormalities. Five of the dogs died within 90 days of diagnosis; death was due to acute renal failure associated with profound dehydration, acidosis, and papillary necrosis. The other dogs remained stable without treatment after 18 months. Histopathology of kidneys did not reveal uniform abnormalities; some dogs had variable and nonspecific changes and others were normal. Electron microscopy did not reveal ultrastructural abnormalities in renal tubular cells. It was concluded that the syndrome in these dogs represents a new entity of renal disease in dogs, similar to idiopathic Fanconi syndrome in man.

Animals↗

Clinical evaluation of glomerular function: 24-hour creatinine clearance in dogs.

Methods of renal clearance to measure glomerular filtration rate (GFR) were compared with plasma creatinine concentration in clinically normal and partially nephrectomized dogs. Glomerular filtration rate was measured by use of a simple 24-hour creatinine clearance method in 36 normal female Beagles. Mean values were 57.6 +/- 9.3 ml/minute/m2 of body surface or 3.7 +/- 0.77 ml/minute/kg of body weight. Variability of this measurement was considerable, as determined in 4 dogs studied on 4 consecutive days. Glomerular filtration rate was measured in the same 36 dogs while they were under anesthesia, using short clearance periods to compare inulin and endogenous creatinine clearance. Mean values for inulin were 41.8 +/- 13.9 ml/minute/m2 of body surface. A close agreement with creatinine clearance was found (correlation coefficient, 0.998). Mean plasma creatinine concentration was 0.82 (range, 0.5--1.0) mg/100 ml. The value of GFR measurement compared with plasma creatinine concentration was determined in 10 dogs after 75% nephrectomy. Sixty days after partial nephrectomy, GFR was reduced to 61% of normal. Mean plasma creatinine and blood urea nitrogen were 1.2 +/- 0.14 mg/100 ml and 20.4 +/- 7.1 mg/100 ml, respectively. Thus, the detection of reduced renal function may be uncertain when plasma creatinine or blood urea nitrogen are used as a means of evaluating renal function. It was concluded that a simple method of creatinine clearance is a sensitive and useful measurement to detect early or borderline reduction in glomerular function.

Anesthesia↗

The fanconi syndrome in Basenji dogs: a new model for renal transport defects.

The renal defects resulting in a Fanconi syndrome were seen in eight Basenji dogs by measuring renal clearance and in vitro amino acid and sugar uptake and performing histopathologic evaluations. Renal tubular handling of glucose, phosphate, sodium, potassium, uric acid, and amino acids was abnormal, and in vitro uptake of labeled lysine, glycine, and alpha-methyl-D-glucoside by renal cortical slices was impaired. Histopathology was normal except for enlarged nuclei in some renal tubule cells. These Basenji dogs, which may be genetically affected, represent a likely model for idiopathic Fanconi syndrome in humans.

Amino Acids↗

Spontaneous Fanconi syndrome in the dog.

Three dogs with spontaneous renal tubular defects similar to idiopathic Fanconi syndrome are characterized. Renal clearance studies revealed a fractional reabsorption of glucose ranging from 31% to 82%. Abnormal glucose thulium values were present in all dogs. A generalized aminoaciduria occurred in two dogs while one had aminoaciduria characteristic of canine cystinuria. Fractional reabsorption of phosphate ranged from 47% to 79%. In vitro uptake of alpha-methyl-D-glucoside was significantly depressed (p less than 0.001). In vitro uptake of amino isobutyric acid was similar to controls. Renal biopsy revealed nonspecific interstitial change in two dogs and normal histology in the other. These animals represent a useful new model for the study of renal tubular transport defects.

Amino Acids↗

Parathyroid function in infants of diabetic mothers.

Serum parathyroid hormone and total and ionized Ca, Mg, and P levels were determined serially from birth to 96 hr of age in 28 infants of diabetic mothers (IDM, 15 Class A, 13 Class B, C, D) and their respective mothers at the time of delivery. In spite of marked decreases in concentrations of serum total and ionized Ca from birth to 24 to 48 hr, there was an insignificant increase in serum PTH values over this period in infants of insulin-dependent mothers. Infants of Class A diabetic mothers had an equivocal PTH response. Nineteen term control infants were similarly examined and had a significant increase in serum PTH postnatally. Relatively higher values of serum ionized Ca at birth in IDM were followed by greater decreases in ionized Ca from birth to 24-48 hr of age, and by decreased neonatal parathyroid function. The data support functional hypoparathyroidism as a basis for the hypocalcemia and hyperphosphatemia of IDM. It is speculated that increased concentrations of serum ionized Ca in utero and suppression of activity in the fetal parathyroid glands may be a cause for the functional hypoparathyroidism.

Blood↗

Solar disinfection of drinking water and diarrhoea in Maasai children: a controlled field trial.

BACKGROUND: Solar radiation reduces the bacterial content of water, and may therefore offer a method for disinfection of drinking water that requires few resources and no expertise. METHODS: We distributed plastic water bottles to 206 Maasai children aged 5-16 years whose drinking water was contaminated with faecal coliform bacteria. Children were instructed to fill the bottle with water and leave it in full sunlight on the roof of the hut (solar group), or to keep their filled bottles indoors in the shade (control group). A Maasai-speaking fieldworker who lived in the community interviewed the mother of each child once every 2 weeks for 12 weeks. Occurrence and severity of diarrhoea was recorded at each follow-up visit. FINDINGS: Among the 108 children in households allocated solar treatment, diarrhoea was reported in 439 of the 2-week reporting periods during the 12-week trial (average 4.1 [SD 1.2] per child). By comparison, the 98 children in the control households reported diarrhoea during 444 2-week reporting periods (average 4.5 [1.2] per child). Diarrhoea severe enough to prevent performance of duties occurred during 186 reporting periods in the solar group and during 222 periods in the control group (average 1.7 [1.2] vs 2.3 [1.4]). After adjustment for age, solar treatment of drinking water was associated with a reduction in all diarrhoea episodes (odds ratio 0.66 [0.50-0.87]) and in episodes of severe diarrhoea (0.65 [0.50-0.86]). INTERPRETATION: Our findings suggest that solar disinfection of water may significantly reduce morbidity in communities with no other means of disinfection of drinking water, because of lack of resources or in the event of a disaster.

Adolescent↗