Search PubMed⌕ Search

Biomedical subjects

C Patterson

Publications and source records attributed to C Patterson.

At least 163 records · Page 9Linked to original sources
PubMed1991

Natural skeletal levels of lead in Homo sapiens sapiens uncontaminated by technological lead.

Lead, Ba and Ca concentrations were determined in tooth enamel, femur and rib from buried skeletons of PreColumbian Southwest American Indians, 10 subjects who lived 1000 years ago on the Pacific coast at 34 degrees N, and 13 subjects who lived 700 years ago in a desert valley tributary of the Colorado River at 37 degrees N 111 degrees W, both groups living in environments uncontaminated by technological Pb. For the coastal tribe, average Pb/Ca ratios were 1.1 x 10(-7) in enamel, 2.3 x 10(-7) in femur and 4.7 x 10(-7) in rib, while Ba/Ca ratios were 1.2 x 10(-5) in enamel, 32 x 10(-5) in femur and 38 x 10(-5) in rib (wt ratios). For the desert tribe, average Pb/Ca ratios were 4 x 10(-7) in enamel, 11 x 10(-7) in femur and 37 x 10(-7) in rib, while Ba/Ca ratios were 1.1 x 10(-5) in enamel, 7.5 x 10(-5) in femur and 6.2 x 10(-5) in rib. It is shown that biologic levels of Pb and Ba in buried femur and rib at both burial sites and in buried enamel at the Arizona site are obscured by excessive diagenetic additions of Pb and Ba from soil moisture. It is shown that one-third of the Pb in enamel at the Malibu site is biologic, yielding a skeletal Pb/Ca (wt) ratio of 4 x 10(-8). This is equivalent to a mean skeletal concentration of 13 ng Pb g-1 bone ash, and a mean natural body burden of 40 micrograms Pb/70 kg adult Homo sapiens sapiens, uncontaminated by technological Pb. This value is about one-thousandth of the mean body burden of 40 mg industrial Pb/70 kg adult American today, which indicates the probable existence within most Americans of dysfunctions caused by poisoning from chronic, excessive overexposures to industrial Pb.

Adult↗
PubMed1991

Increased incidence of respiratory distress syndrome in babies of hypertensive mothers.

There is controversy over the effect of hypertension in pregnancy on the incidence of neonatal respiratory distress syndrome. We investigated the association between maternal hypertension and the incidence of respiratory distress syndrome in 268 very low birthweight babies of less than 34 weeks' gestation. A lower incidence of respiratory distress syndrome was associated with growth retardation and membrane rupture greater than 24 hours. Maternal hypertension was associated with an increased incidence of respiratory distress syndrome. We used the multiple logistic regression model to control for confounding variables, as the maternal and neonatal factors associated with respiratory distress syndrome were not evenly distributed between the two groups. After adjustment for birth weight, gestational age, growth retardation, and membrane rupture greater than 24 hours, the risk of developing respiratory distress syndrome was significantly greater in babies of hypertensive mothers. Significance was lost when labour before delivery and mode of delivery were taken into account. The increased incidence of respiratory distress syndrome in babies of hypertensive mothers may be due to the absence of labour before delivery because of the greater likelihood of caesarean section.

Cesarean Section↗
PubMed1990

Diagnosis of iron-deficiency anemia in the elderly.

PURPOSE: To determine the value of serum ferritin, mean cell volume, transferrin saturation, and free erythrocyte protoporphyrin in the diagnosis of iron-deficiency anemia in the elderly. PATIENTS AND METHODS: We prospectively studied consecutive eligible and consenting anemic patients over the age of 65 years, who underwent blood tests and bone marrow aspiration. The study consisted of 259 inpatients and outpatients at two community hospitals in whom a complete blood count processed by the hospital laboratory demonstrated previously undiagnosed anemia (men: hemoglobin level less than 12 g/dL; women: hemoglobin level less than 11.0 g/dL). RESULTS: Thirty-six percent of our patients had no demonstrable marrow iron and were classified as being iron-deficient. The serum ferritin was the best test for distinguishing those with iron deficiency from those who were not iron-deficient. No other test added clinically important information. The likelihood ratios associated with the serum ferritin level were as follows: greater than 100 micrograms/L, 0.13; greater than 45 micrograms/L but less than or equal to 100 micrograms/L, 0.46; greater than 18 micrograms/L but less than or equal to 45 micrograms/L, 3.12; and less than or equal to 18 micrograms/L, 41.47. These results indicate that values up to 45 micrograms/L increase the likelihood of iron deficiency, whereas values over 45 micrograms/L decrease the likelihood of iron deficiency. Seventy-two percent of those who were not iron-deficient had serum ferritin values greater than 100 micrograms/L, and in populations with a prevalence of iron deficiency of less than 40%, values of greater than 100 micrograms/L reduce the probability of iron deficiency to under 10%. Fifty-five percent of the iron-deficient patients had serum ferritin values of less than 18 micrograms/L, and in populations with a prevalence of iron deficiency of greater than 20%, values of less than 18 micrograms/L increase the probability of iron deficiency to over 95%.

Aged↗
PubMed1990

Atrial and ventricular arrhythmias in asymptomatic active elderly subjects: correlation with left atrial size and left ventricular mass.

Elderly normal subjects have an increased prevalence of cardiac arrhythmias compared with young and middle-aged subjects. The objective of this study was to test the hypothesis that the incidence and complexity of atrial and ventricular arrhythmias may be related to either left atrial enlargement or to increased left ventricular mass, respectively. From 146 asymptomatic volunteers older than 60 years, 86 subjects were considered to be free of cardiovascular abnormalities and had adequate M-mode echocardiograms and 24-hour ambulatory electrocardiograms. The mean age was 72 +/- 7 years, with a range of 60 to 96 years. There were 37 men and 49 women. During 1415 +/- 73 minutes of ambulatory electrocardiography, the average heart rate was 72 +/- 8 beats/min in men and 76 +/- 6 beats/min in women (p less than 0.05). Atrial arrhythmias were present in 64 subjects (74%); the frequency and complexity of these arrhythmias correlated with left atrial size (p less than 0.01). Ventricular arrhythmias were present in 55 subjects (64%); the frequency and complexity of ventricular arrhythmias did not correlate with left ventricular mass index. These results suggest that left atrial dilatation, a normal development in healthy elderly subjects, plays a significant role in the pathophysiology of the increased incidence of atrial arrhythmias. Increased left ventricular mass, which also occurs normally in the aging heart, is not, on the other hand, associated with an increased frequency and/or complexity of ventricular arrhythmias.

Aged↗
PubMed1990

Intravenous diclofenac sodium. Does its administration before operation suppress postoperative pain?

Intravenous diclofenac sodium was evaluated in a double-blind randomised trial relative to intramuscular diclofenac, intravenous fentanyl, and intramuscular placebo in 160 patients undergoing extraction of impacted lower third molar teeth. The test drug was administered before operation in an attempt to alleviate postoperative pain. A 10-cm visual analogue scale was used to assess pain at 30 minutes and one day after surgery, if the patients stayed overnight. Patients who received intravenous diclofenac had significantly less pain than the other groups 30 minutes after operation. They also had significantly less pain one day after surgery than the placebo or opioid groups, but not less than the intramuscular diclofenac group. Capillary bleeding time, in comparison with placebo, was significantly prolonged after the use of intramuscular diclofenac, and a similar but nonsignificant trend was observed in the intravenous diclofenac group. No problems were encountered with excessive bleeding in any group.

Adolescent↗
PubMed1990

Colorectal cancer in the north and south of Ireland 1950-1984.

STUDY OBJECTIVE: Northern Ireland has the highest standardised mortality ratios for colon cancer in the United Kingdom and the Republic of Ireland has some of the highest mortality rates for cancer in the world. The aim of the study therefore was to investigate trends in colorectal cancer in the north and south of Ireland over the period 1950 to 1984. DESIGN: The study was a cohort analysis of deaths from colorectal cancer for ages 35-74 years by five year age groups, divided by sex. SETTING: This was a population study involving all cases reported to the Registrar General of Northern Ireland and the Eire Vital Statistics and Central Statistical Office during the study period. MEASUREMENTS AND MAIN RESULTS: As in mainland Britain, rectal cancer mortality declined in the north and the south during the study period, but the fall began sooner for males than females. Colon cancer mortality fell in the late 1950s but subsequently rose to its previous high levels. CONCLUSIONS: The observation that there were declines in mortality in the north and south of Ireland in the late 1950s does not support the hypothesis that altered diet due to war rationing in Great Britain and Northern Ireland underlay the fall in British colon cancer mortality after the war. The very high standardised mortality ratios for colon cancer in Northern Ireland highlight a continuing major public health problem in the region.

Adult↗
PubMed1989

Surgical wound infections.

At the last meeting of the SURGIKOS Operating Room/Infection Control Combined Advisory Panel, guest speakers reviewed current thinking and practices that have an impact on surgical wound infections. Presentation topics included the role of the CDC, nursing and classification systems in controlling wound infections; cost effective epidemiologic methods of reducing infections; and outcomes of surgical wound infection prevention practices deemed critical by the Joint Commission on Accreditation of Healthcare Organizations. The following is a brief overview of the presentations that guided panel discussions on these topics.

Antisepsis↗
PubMed1989

Measurement of circulating immune complexes containing IgG, IgM, IgA and IgE by flow cytometry: correlation with disease activity in patients with systemic lupus erythematosus.

The immunoglobulin (Ig) class of the antibody component of circulating immune complexes (IC) may be an important determinant of their pathogenicity. This study reports the development of a fluorometric immunoassay, using Raji cells as solid phase component and detection by flow cytometry, for the measurement of IC containing IgG, IgM, IgA and IgE. Analytic specificity of the method was established and diagnostic sensitivity determined in groups of patients with various disorders. In a detailed study of 44 patients with systemic lupus erythematosus (SLE), elevated levels of IC were observed in the majority of patients, the prevalence of the respective Ig subclasses within the patient group being IgG-IC (93%); IgM-IC (77%); IgA-IC (59%); IgE-IC (52%). Raised levels of IC (of all classes) correlated with disease activity. Longitudinal study of a patient with acute cerebral SLE revealed elevated IC levels of all four Ig classes at presentation which fell during treatment, coincident with normalization of complement values. The biological consequences of IC of various Ig subclasses is discussed with particular reference to a possible mechanism of IgE-IC mediated tissue damage.

Adult↗
PubMed1989

Acute decompensation in dementia: recognition and management.

Dementing illnesses are chronic disorders causing global impairment of intellectual function. The most common cause is Alzheimer's disease, and this, together with most other forms of dementing illness, is relentlessly progressive. Frequently, however, there is an abrupt deterioration in physical, behavioral, or cognitive function in someone who is known to suffer from a dementing illness. This article outlines an approach to the many factors capable of producing such acute decompensation.

Acute Disease↗
PubMed1988

Homology in classical and molecular biology.

Hypotheses of homology are the basis of comparative morphology and comparative molecular biology. The kinds of homologous and nonhomologous relations in classical and molecular biology are explored through the three tests that may be applied to a hypothesis of homology: congruence, conjunction, and similarity. The same three tests apply in molecular comparisons and in morphology, and in each field they differentiate eight kinds of relation. These various relations are discussed and compared. The unit or standard of comparison differs in morphology and in molecular biology; in morphology it is the adult or life cycle, but with molecules it is the haploid genome. In morphology the congruence test is decisive in separating homology and nonhomology, whereas with molecular sequence data similarity is the decisive test. Consequences of this difference are that the boundary between homology and nonhomology is not the same in molecular biology as in morphology, that homology and synapomorphy can be equated in morphology but not in all molecular comparisons, and that there is no detected molecular equivalent of convergence. Since molecular homology may reflect either species phylogeny or gene phylogeny, there are more kinds of homologous relation between molecular sequences than in morphology. The terms paraxenology and plerology are proposed for two of these kinds--respectively, the consequence of multiple xenology and of gene conversion.

Anatomy, Comparative↗
PubMed1988

A randomized trial of quality assurance in nursing homes.

Sixty nursing homes were randomly allocated to receive or not to receive a quality assurance intervention. The experimental intervention included the use of predeveloped quality assurance packages, the services of a quality assurance consultant, and the process of working through the quality assurance cycle with one of two principal indicator conditions. Two prevalent health problems, hazardous mobility and constipation, were selected as the principal indicator conditions. To detect co-intervention, one of two hidden secondary indicator conditions (potential skin breakdown and urinary incontinence) was assessed in each facility. In the control nursing homes, both the principal and secondary indicator conditions were hidden from staff. The care for 1,525 residents was examined before and after the intervention using a retrospective record review initiated for the study purposes. Improvement in management of the principal conditions, hazardous mobility and constipation, was greater in the experimental group (P less than 0.03 and P less than 0.005, respectively). Neither group changed its management of the hidden conditions. Behavior change was achieved using quality assurance-linked interventions. Further research should focus on refining quality assurance interventions that provide staff education and motivational strategies.

Accidental Falls↗
PubMed1987

Disseminated Mycobacterium bovis infection in an elderly patient.

We report a fatal case of disseminated infection due to Mycobacterium bovis occurring in an elderly patient. The greatest incidence of tuberculosis is in the aged, who were likely to have been infected in childhood when the disease was more prevalent. However, the clinical or radiographic presentation of tuberculosis in the older patient may be atypical or nonspecific, contributing to delay in diagnosis, and greater morbidity and mortality.

Aged↗