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J C Sinclair

Publications and source records attributed to J C Sinclair.

At least 55 records · Page 3Linked to original sources
PubMed1981

Evaluation of neonatal-intensive-care programs.

Within the past 15 years, regional neonatal-intensive-care programs have been introduced and have expanded rapidly. The efficacy of some of the individual interventions that constitute neonatal intensive care has been validated in randomized, controlled clinical trials. It is therefore generally assumed that neonatal-intensive-care programs that incorporate these maneuvers are effective in reducing death and disability. However, the overall effectiveness of these programs has not been tested experimentally. Moreover, much of the non-experimental evidence supporting their value is based on the experience of referral units and does not measure the impact on the populations they serve. A definitive economic evaluation of neonatal intensive care has not yet been reported, despite the high cost of such programs. We conclude that neonatal-intensive care programs require further evaluation with rigorous scientific methods.

Clinical Trials as Topic↗
PubMed1981

Inability to detect hepatitis B surface antigen (HBsAg) in the duodenum of HBsAg-positive persons.

Incubation of hepatitis B surface antigen (HBsAg)-positive serum with duodenal fluid (DF) of normal persons results in marked reduction of immunoreactivity. This was shown to be caused by: (1) interference with radioimmunoassay (RIA) system and (2) actual destruction of HBsAg. The interference in the RIA system could be counteracted by addition of bovine serum and a reproducible detection system of HBsAg in DF was established. DF of HBsAg-positive persons was negative for HBsAg. One HBsAg carrier who had a partial pancreatectomy for an insulinoma had separate cannulae in his bile and pancreatic ducts. Whereas HBsAg could be detected in bile, it was undetectable in pancreatic juice. Incubation of his pancreatic juice with his bile resulted in disappearance of HBsAg. It appears that a factor present in pancreatic juice, or resulting from the interaction of pancreatic juice and bile, results in disappearance of HBsAg immunoreactivity.

Bile↗
PubMed1981

Analysis of newborn intensive care by time-lapse photography.

The activities of nurses, residents, and fellows providing newborn intensive care were studied by time-lapse photography. Six of 40 frames taken each hour during a 23-day period were evaluated. Time spent in bedside care, charting, handwashing, and other activities were estimated for personnel in a four-bed area. The amount of care prescribed for each infant was assessed independently by calculation of a care score from the physicians' orders. Physician activities were significantly diminished at night and on weekends. Bedside care given by physicians increased abruptly at high care scores. Total bedside nursing care was unaffected by time-related variables (day vs. night; weekday vs. weekend; nursing rotations). Regression analysis showed a linear two- to three-fold increase in bedside nursing time with increasing care score. Individual nurses differed significantly in mean time devoted to bedside care and in their response to increasing infant care score. Differences between nurses accounted for as much of the total variation in bedside care (30%) as did differences between infants in care needs. Many factors are likely to affect the individual or group performance of nursery staff. The traditional duty schedule for physicians is associated with a deterioration in their performance at night and the nocturnal increase in neonatal acidosis and mortality previously reported by the authors.

Humans↗
PubMed1980

Hepatitis non-A, non-B.

Evidence for the existence of hepatitis non-A, non-B includes epidemiologic data and results of transmission studies indicating the presence of hepatitis that could not be explained by known causative agents. The diagnosis is suggested in patients who have multiple episodes of acute hepatitis or who contract hepatitis after transfusion, hemodialysis or drug abuse. Sporadic cases are common. Three such cases are described to illustrate that the disease is clinically indistinguishable from hepatitis A or B. The diagnosis is based on the absence of serologic markers of hepatitis A and B and of infection by Epstein-Barr virus and cytomegalovirus, or on serologic evidence of previous infection with hepatitis A and B.

Adult↗
PubMed1979

Diurnal variation in the quality and outcome of newborn intensive care.

Variables related to both the process and the outcome of neonatal intensive care were studied to compare care given during the day (0901-2100 hours) with that at night (2101-0900 hours). At night, intravenous infiltrations occurred more often, and the tidal volume of respirator-treated infants was verified less often. Blood pH values less than 7.20, excluding values within 12 hours of admission, were recorded more often and in more patients at night. During a 12-month period, there were significantly more deaths among infants less than 1,500 gm during the night than during the day. The deterioration of infants at night may result in part from current nursery staffing practices.

Birth Weight↗
PubMed1979

Failure to detect hepatitis B surface antigen (HBsAg) in feces of HBsAg-positive persons.

Since previous studies did not provide conclusive data regarding the presence of hepatitis B surface antigen (HBsAg) in the feces of HBsAg carriers, the feces of 20 HBsAg carriers and six patients with HBsAg-positive active liver disease were examined with use of a reproducible method for concentrating and detecting HBsAg in feces in which bovine serum, which has been shown to protect HBsAg destruction by fecal components, was added to the fecal specimens. HBsAg was not detected in 66 fecal specimens from the 26 HBs-Ag-positive persons. Furthermore, HBsAg could not be detected in the feces of a carrier who had ingested 4 ml of his own serum. This finding suggests that there are factors in the gastrointestinal tract that interfere with the immunoreactivity of the HBsAg and possibly destroy the hepatitis B virus. These findings explain why oral/fecal spread does not play a major role in the transmission of hepatitis B virus.

Carrier State↗
PubMed1979

Vitamin E absorption in small premature infants.

The absorption of vitamin E, given by orogastric tube, was studied in premature infants who weighed less than 1.5 kg at birth. After the administration of either dl-alpha tocopherol or the acetate form, plasma tocopherol levels increased. In a second blind trial, 28 infants received either 25 units of dl-alpha tocopherol or placebo during the first six weeks of life. Plasma tocopherol levels in all treated infants were sustained in the normal adult range. The vitamin E-deficient state of premature infants can be corrected by oral therapy alone.

Administration, Oral↗
PubMed1978

Hepatitis and hepatitis B surface antigen and antibody in dentists.

Dentists were surveyed regarding a history of hepatitis and the presence in the blood of hepatitis B surface antigen (HBsAg) and antibody (anti-HBs) to determine whether they were at high risk of exposure to hepatitis B virus. Of 288 Canadian dentists 5.2% gave a history of hepatitis after graduation. This proportion is similar to that for 1462 Ontario dentists (6.3%) and that for 3162 accountants (5.1%) who had previously completed a mailed questionnaire. One dentist (0.3%) was HBsAg-positive and 42 (14.6%) were anti-HBs-positive. Of 210 healthy volunteer blood donors matched for age, sex and ethnic origin with the group of dentists none was HBsAg-positive and 2.9% significantly fewer (P less than 0.005), were anti-HBs-positive. Among Ontario blood donors 0.3% were HBsAg-positive and 3% were anti-HBs-positive. Thus, in Canada, dentists are not at increased risk of acquiring clinical hepatitis or becoming carriers, but they are more likely than other groups to have anti-HBs in the blood. Among dentists from outside Canada a higher proportion had a history of hepatitis (10.3%) and were HBsAg-positive (1.6%), but approximately the same proportion were anti-HBs-positive (15.9%).

Antibodies, Viral↗
PubMed1978

Hepatitis in undertakers.

Six of 106 undertakers (5.6%) gave a past history of hepatitis during their professional careers; this was no different from the frequency in a control group of 3,162 accountants (5.1%) who had no direct contact with blood. None of the undertakers or 210 blood donors matched for age, sex, and ethnic background had serum positive for hepatitis B surface antigen. Five undertakers (4.7%) had blood that was positive for antibody to hepatitis B surface antigen, compared with six of 210 (2.9%) in the control group; this difference was not statistically significant (P greater than .25). Thus, undertakers appear to be in a low-risk occupation with reference to acquisition of hepatitis B. Although the numbers are too small for statistical analysis, there appeared to be an increased exposure to hepatitis B in undertakers who take no preventive precautions. We recommend that the minimal precautions for undertakers be the wearing of gloves.

Adult↗
PubMed1978

Experimental design deck for clinical research: A new learning resource in aid of scientific thinking.

The Experimental Design Deck for Clinical Research is a simulation of a problem in experimental design in a card deck format. It is intended to stimulate the development of skills in scientific thinking by allowing the student, in a self-directed fashion, to design a clinical trial to test either a given hypothesis (specific deck) or a hypothesis that the player provides (general deck). In addition to its use as an educational tool, the Experimental Design Deck can be used as a guide to the application of scientific thinking in a variety of biomedical activities. It can easily be modified for application to problems in nonmedical research and evaluation.

Clinical Trials as Topic↗
PubMed1977

Urine solute excretion in growing low-birth-weight infants.

Fifteen thriving low-birth-weight infants who weighed less than 1,950 gm at birth were randomly selected to study the urine solute excretion on two milk-based proprietary formulas, SMA or Formula 4. The results showed that urine oxmolality rose progressively with increasing caloric concentration and was 78, 111, and 163 mOsm/kg H2O on 67, 80, and 100 kCal/dl SMA, respectively. Formula 4 gave rise to significantly higher urine osmolality (133 mOsm/kg H2O) than SMA, when fed at the same caloric density of 67 kCal/dl. Although the dependence of urine solute excretion on dietary load was confirmed, the rapidly growing low-birth-weight infant appears to incorporate a larger portion of potential urine solute into growing tissues, than is the case in the term infant.

Animals↗
PubMed1976

Practical guidelines for assessing patients positive for hepatitis B surface antigen.

In assessing the patient the hepatitis B surface antigen (HBsAg) the physician must decide on the basis of physical findings, results of laboratory tests and biopsy, when indicated, whether the patient is an asymptomatic carrier or has acute or chronic hepatitis. Asymptomatic carriers of HBsAg must be educated in personal hygiene and the possibility of transmission, should not be allowed to donate blood or breast-feed and should not work with blood products for human use or pharmaceutical products designated for intravenous use. However, it is otherwise not necessary to advise these individuals to change their profession.

Carrier State↗
PubMed1976

Hepatitis B surface antigen and antibody in asymptomatic blood donors.

Seventy-two volunteer blood donors who had hepatitis B surface antibody (anti-HBS) were studied and compared with 115 carriers of hepatitis B surface antigen (HBSAg). Anti-BHS-positive donors gave a history of greater possible exposure to hepatitis B virus, there was a lower male-female ratio, and they had a much lower frequency of abnormal hepatic function test results. Those who were positive by counterimmunoelectrophoresis (CIEP), which indicated a high titer of antibody (greater than 1:2,000 as measured by passive hemagglutination assay [PHA], also had an ethnic origin similar to that of the donor panel, ie, predominantly Canadian and northern European. The HBSAg carriers, on the other hand, had a high frequency of origin from Mediterranean and Far Eastern countries. Low-antibody-titer (positive PHA but negative CIEP) donors had ethnic origins that more closely approximated those of HBSAg carriers.

Antibodies↗
PubMed1975

e antigen and anti-e in HBsAg carriers.

A new antigen/antibody system, "e" and anti-e, was described in 1972. In order to assess the clinical significance of e antigen and anti-e, their presence was correlated with the clinical status, S.G.P.T. levels and liver biopsies of HBsAg carriers. 31 of the carriers had liver biopsies, 32 of 70 carriers had anti-e and 2 had e antigen. 28 of 55 carriers with normal S.G.P.T. and 4 of 15 patients with raised S.G.P.T. had anti-e. This difference is not statistically significant. 2 patients with e had raised S.G.P.T. All patients with normal histology, 45% of patients with mild, and 23% of patients with striking histological changes in the liver had anti-e. This association of anti-e with a normal or mildly abnormal liver was statistically significant. The 2 patients with e antigen had the most severe abnormalities in liver function and liver histology.

Alanine Transaminase↗
PubMed1975

Prevalence and significance of hepatitis B surface antigen in a general hospital.

Over a 6-month period 2025 patients admitted to New Mount Sinai Hospital, Toronto were screened for hepatitis B surface antigen (HBsAg) by counter-immunoelectrophoresis (CIEP) and radioimmunoassay (RIA). CIEP detected 12 HBsAg-positive patients and RIA 16. RIA is therefore the more sensitive test for HBsAg. Of the 16 patients 2 had liver disease previously diagnosed, 3 had malignant disease and 11 were asymptomatic carriers. Of the 11 carriers all were born in countries where the carrier rate is known to be high. Routine screening of hospital patients on admission is of no value in detecting unsuspected liver disease but is of value in detecting asymptomatic carriers, which is of importance for the patient and his family. Routine screening tests for HBsAg in Canadian hospitals that treat many patients born in countries with a known high HBsAg prevalence is recommended. Routine screening is also recommended in all hospitals in Mediterranean and Asian countries.

Carrier State↗