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D Barker

Publications and source records attributed to D Barker.

At least 37 records · Page 2Linked to original sources
PubMed2002

Shortness at birth is associated with insulin resistance in pre-pubertal Jamaican children.

AIM: To investigate the relationship between anthropometry at birth and glucose/insulin metabolism in childhood using the response to an oral glucose challenge. METHOD: Four hundred mother/child pairs on whom gestational and birth data were available were studied. After an overnight fast, anthropometric measurements were made on the children and an oral glucose tolerance test performed. The plasma concentrations of insulin, pro-insulin and 32-33 split pro-insulin were also measured. Skinfold thicknesses were used to calculate percentage body fat and fat mass was derived from the percentage fat and absolute weight. RESULTS: The mean age of the children was 8 y (range 7.5-10.5), and six exhibited impaired glucose tolerance based on WHO criteria. Insulin concentration 120 min after the oral glucose load (a measure of insulin resistance) was inversely related to length at birth (P<0.005). The children who were in the shortest quartile at birth and were heaviest at 8 y old had the highest insulin concentration. CONCLUSION: Shortness at birth is related to insulin resistance. Such insensitivity to the action of insulin is greater in heavier children.

Blood Glucose↗
PubMed2002

Size at birth, fat-free mass and resting metabolic rate in adult life.

Resting metabolic rate is an important predictor of obesity and is closely related to fat-free mass. There is evidence that fat-free mass may be partly determined during critical periods of growth before and after birth. The objective of this study was to examine the relationship between size at birth, childhood growth and fat-free mass and resting metabolic rate in adult life. 318 men and women with detailed records of body size at birth and growth during school years participated in the study. Fat-free mass correlated positively with birth weight among both sexes (r = 0.264, p < 0.001). Those having a higher birth weight had a higher fat-free mass at any adult BMI. Fat-free mass among men increased by 2.2 kg (95 % Cl 0.5 to 3.9; p = 0.01) for every kg increase in birth weight and by 1.5 kg (95 % Cl 1.3 to 1.7, p < 0.0001) for every kg/m(2) BMI in adult life. In women, fat-free mass increased by 2.7 kg (95 % Cl 1.6 - 3.9; p < 0.001) for every kg increase in birth weight and by 0.8 kg (95 % CI 0.7 to 1.0, p < 0.001) for every kg/m(2) of BMI in adult life. Height, weight and body mass index at each age from 7 to 15 years were also strongly, positively associated with fat-free mass. A negative correlation between birth weight and resting metabolic rate expressed per unit of fat-free mass (r = - 0.158; p < 0.001) was found. Fat-free mass may be determined during critical periods of muscle growth in utero and during childhood. The muscle tissue of people who had a lower birth weight is more metabolically active than those with a higher birth weight. This may protect them from the increased risk of obesity associated with low fat-free mass.

Adolescent↗
PubMed2002

The use of glyceryl trinitrate ointment with EMLA cream for i.v. cannulation in children undergoing routine surgery.

This prospective randomized controlled double-blind trial was performed to investigate whether glyceryl trinitrate (GTN) ointment, applied ten minutes after the removal of a eutectic mixture of local anaesthetic cream, lignocaine/ prilocaine (EMLA), influences site selection for intravenous cannulation in children. Eighty children aged between five and 15 years, having general surgery as day patients, received EMLA cream on both hands for 90 minutes prior to transfer to the theatre suite. Acting as their own controls, the children received GTN on one hand, and placebo on the other, after removal of the EMLA cream and ten minutes prior to the insertion of an intravenous cannula. The application of GTN or placebo to left or right hand was blinded and randomized. At induction, the hand with the visually best quality veins was selected and cannulated. The primary outcome was selection between the EMLA/GTN hand and EMLA/placebo hand. The selection having been made, the number of attempts at cannulation, ease of insertion and pain scores (VAS) for cannulation were also recorded. The choice of hand was positively influenced by the use of GTN, with the GTN hand chosen in 51 of 72 (70%) children who completed the protocol (P = 0.001). The findings of this study suggest that the application of GTN after EMLA removal may be clinically useful in aiding cannulation in children.

Administration, Topical↗
PubMed2002

Primary malnutrition. Can we always tell?

Patterns of disease in the English-speaking Caribbean have changed considerably over the past two decades. There has been a decrease in the incidence of common infectious diseases, an increase in the prevalence of chronic non-communicable disorders and an increase in the incidence and prevalence of HIV/AIDS. However, published estimates suggest that malnutrition continues to be a serious public health problem. It is possible that changing patterns of disease within the epidemiological transition may affect patterns of presentation of severe forms of childhood malnutrition. We have examined records of 435 children admitted to the clinical research ward of the Tropical Metabolism Research Unit (TMRU) from January 1, 1990, to December 31, 1999; among these were 25 children who were subsequently found to have severe childhood malnutrition (SCM) due to a defined medical or surgical disorder (i.e. secondary SCM). Among children with secondary SCM, the HIV/AIDS group was the largest and comprised 60% of these admissions. Regression analyses show that, over the ten-year period, there was a small, non-significant decline in the number of cases of primary SCM (incidence rate ratio, IRR = 0.99, 95% confidence interval = 0.96, 1.02, p = 0.98), while the number of cases of secondary SCM increased (IRR = 1.18, 95% CI = 1.03, 1.35, p = 0.02). These data are indicative of the need for continued vigilance in the evaluation of children who have clinical features of the syndromes of severe malnutrition and draw attention to the potential impact of HIV/AIDS in yet another area of healthcare delivery.

Child↗
PubMed2001

Ridge augmentation using mandibular tori.

A 19-year-old female was referred by her dental practitioner for the restoration of missing maxillary lateral incisors and canines. Ridge augmentation was required. This was undertaken using mandibular tori as the sites for harvesting bone. The grafting was successful and the spaces were subsequently restored using resin-bonded bridgework. The case reports that mandibular tori provide a local and convenient source of bone for ridge augmentation procedures.

Adult↗
PubMed2001

Comparison of ketorolac tromethamine 0.5% and rimexolone 1% to control inflammation after cataract extraction. Prospective randomized double-masked study.

PURPOSE: To compare the efficacy of a topical nonsteroidal anti-inflammatory agent (ketorolac tromethamine 0.5%) with that of a topical steroid (rimexolone 1%) to control inflammation after cataract surgery. SETTING: Storm Eye Institute, Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina, USA. METHODS: Thirty-six patients were prospectively and randomly assigned to receive topical treatment with either ketorolac tromethamine 0.5% or rimexolone 1% starting the day after routine cataract extraction. Treatment was masked to both patient and investigator. Each patient had uneventful small incision phacoemulsification with placement of a foldable posterior chamber intraocular lens. Patients used 1 of the 2 antiinflammatory agents 4 times each day starting 24 hours after surgery. No antiinflammatory medications were used preoperatively, intraoperatively, or for 24 hours postoperatively. Signs and symptoms of inflammation, intraocular pressure (IOP), and Kowa cell and flare measurements were evaluated 1, 4, 7, and 30 days postoperatively. RESULTS: There was no statistically significant difference in any measurement of postoperative inflammation between the 2 groups. There was no difference in objective or subjective cell and flare measurements. In addition, there was no difference in IOP measurements between groups. CONCLUSIONS: Ketorolac tromethamine 0.5% was as effective as rimexolone 1% in reducing inflammation after cataract surgery. These results suggest that ketorolac tromethamine 0.5% is a safe and effective antiinflammatory alternative to steroids after cataract extraction.

Aged↗
PubMed2001

Size at birth, childhood growth and obesity in adult life.

BACKGROUND: Several studies have shown tracking of obesity from childhood to adult life. People who develop obesity in adult life may therefore have had a particular path of growth from birth through childhood. OBJECTIVE: To examine the relationship of obesity to size at birth and childhood growth. DESIGN: Birth cohort study. PARTICIPANTS: A total of 5210 individuals alive and living in Finland in 1997, who were born at the Helsinki University Central Hospital between 1924 and 1933 and who went to school in Helsinki were sent a questionnaire in order to get information about adult weight and height. Detailed birth and school health records were available for all subjects. In all, 3847 responded and 3659 (1552 men and 2107 women) with adequate data are included in the present study. MEASUREMENTS: Incidence of obesity based upon lifetime maximum body mass index (BMI) ascertained from a postal questionnaire and defined as a BMI>30 kg/m(2). The main explanatory measurements were size at birth and childhood growth in height, weight and BMI. RESULTS: The cumulative incidence of obesity was 34.2% in men and 33.9% in women. The incidence rose with increasing birth weight and ponderal index (birthweight/length(3); P=0.01 and P=0.04, respectively). These associations were statistically significant only among males. By the age of 7 y the mean weights, heights and BMI of people who later became obese exceeded the average and remained above average at all ages from 7 to 15 y. In both men and women there was a 3-fold increase in obesity associated with a BMI>16 kg/m(2) at age 7 compared with a BMI<14.5 kg/m(2) (P<0.0001). Boys and girls whose mothers had a high BMI in pregnancy had more rapid childhood growth and an increased risk of becoming obese. This effect was stronger among boys (P=0.008). CONCLUSIONS: Obesity is initiated early in life. These results emphasise the importance of early preventive measures for its treatment.

Adolescent↗
PubMed2000

The fetal and childhood growth of persons who develop type 2 diabetes.

BACKGROUND: Type 2 diabetes is associated with low birthweight followed by obesity in adulthood. Persons who develop the disease may therefore have a particular pattern of growth from birth through childhood. OBJECTIVE: To examine the relation of type 2 diabetes to size at birth and childhood growth. DESIGN: Cohort study. SETTING: Helsinki, Finland. PARTICIPANTS: Men (n = 3,639) and women (n = 3,447) who were bom at the Helsinki University Central Hospital between 1924 and 1933, who went to school in Helsinki, and who still lived in Finland in 1971. Detailed birth and school health records were available for all 7,086 participants. We identified 471 men and women who developed type 2 diabetes by using the national Social Insurance Institution's register of all persons in Finland who are receiving long-term therapy with medication. MEASUREMENTS: Incidence of diabetes ascertained from a national register. The main explanatory measurements were size at birth and childhood growth in terms of height, weight, and body mass index. RESULTS: The cumulative incidence of type 2 diabetes was 7.9% (n = 286) in men and 5.4% (n = 185) in women. The incidence increased with decreasing birthweight, birth length, ponderal index (birthweight/length(3)), and placental weight The odds ratio for type 2 diabetes was 1.38 (95% CI, 1.15 to 1.66; P < 0.001) for each 1-kg decrease in birthweight. The mean weights and heights of the children at 7 years of age who later developed type 2 diabetes were about average. Thereafter, their growth in weight and height was accelerated until 15 years of age. The odds ratio for development of type 2 diabetes was 1.39 (CI, 1.21 to 1.61; P < 0.001) for each standard deviation increase in weight between 7 and 15 years of age. The odds ratio became 1.83 (CI, 1.37 to 2.45; P< 0.001) in an analysis restricted to persons whose birthweights were below 3,000 g. Children of both sexes whose mothers had a high body mass index in pregnancy had more rapid growth during childhood and an increased incidence of type 2 diabetes. CONCLUSIONS: These findings are consistent with the hypothesis that type 2 diabetes is programmed in utero in association with low rates of fetal growth. The increased risk for type 2 diabetes associated with small size at birth is further increased by high growth rates after 7 years of age.

Adolescent↗
PubMed2000

Development of a toxicological gene array and quantitative assessment of this technology.

High-density arrays of DNA bound to solid substrates offer a powerful approach to identifying changes in gene expression in response to toxicants. While DNA arrays have been used to explore qualitative changes in gene regulation, less attention has focused on the quantitative aspects of this technology. Arrays containing expressed sequence tags for xenobiotic metabolizing enzymes, proteins associated with glutathione regulation, DNA repair enzymes, heat shock proteins, and housekeeping genes were used to examine gene expression in response to beta-naphthoflavone (beta-NF). Upregulation of cytochrome P4501a1 (Cyp1a1) and 1a2 in mouse liver was maximal 8 h after beta-NF administration. Significant upregulation of Cyp1a2 was noted at beta-NF doses as low as 0.62 and 1.2 mg/kg when gene expression was measured by microarray or Northern blotting, respectively. Maximal Cyp1a2 induction is 5-fold by Northern analysis and 10-fold by microarray. Induction of Cyp1a1 was 15- and 20-fold by Northern and microarray analysis, respectively. The coefficient of variation for spot to spot and slide to slide comparisons was <15%; this variability was smaller than interanimal variability (18-60%). Comparison of mRNA expression in control animals indicated that there are differences in labeling/detection associated with Cy3/Cy5 dyes; accordingly, experiments must include methods for establishing baseline signals for all genes. We conclude that the dynamic range and sensitivity of DNA microarrays on glass slides is comparable to Northern blotting analysis and that variability of the data introduced during spotting and hybridization is less than the interanimal variability.

Animals↗
PubMed2000

Effects of infant birthweight and maternal body mass index in pregnancy on components of the insulin resistance syndrome in China.

BACKGROUND: Reduced birthweight is associated with increased risk for the insulin resistance syndrome. Part of this risk is hypothesized to originate from undernutrition in utero. The prevalence of the insulin resistance syndrome increases in countries that undergo the transition from chronic malnutrition to adequate nutrition, when postnatal nutrition improves more rapidly than prenatal nutrition. OBJECTIVE: To determine whether the components of the insulin resistance syndrome are associated with reduced fetal growth and maternal undernutrition. DESIGN: A nonconcurrent, prospective study of men and women whose mothers' heights and weights were recorded during pregnancy. SETTING: Beijing, China. PARTICIPANTS: 627 men and women (mean age, 45 years) whose mothers' obstetric records were preserved. MEASUREMENTS: Adult offspring's blood pressure, plasma glucose levels, insulin levels, and lipid concentrations during an oral glucose tolerance test. The main explanatory measurements were mothers' body mass index during pregnancy and offspring's birthweight and adult size. RESULTS: After adjustment for sex and current body mass index, low birthweight was associated with elevated plasma glucose levels, insulin levels, triglyceride concentrations, and blood pressure. For every 1-kg increase in birthweight, systolic blood pressure decreased by 2.9 mm Hg (95% CI, 0.3 to 5.4 mm Hg) and the 2-hour plasma glucose level decreased by 5.1% (CI, 0.7% to 9.3%). Low maternal body mass index in early and late pregnancy was associated with elevated levels of plasma glucose, insulin, and triglycerides in adult offspring but was not associated with elevated blood pressure. CONCLUSIONS: Risk for the insulin resistance syndrome may be partially established through low maternal body mass before pregnancy and consequent fetal undernutrition. This risk is independent of that associated with adult obesity. In developing countries such as China, improved nutrition in girls and young women may offer long-term benefits to offspring.

Adult↗
PubMed2000

Political talk radio and public opinion.

This article examines the relationship between listening to political talk radio (Rush Limbaugh in particular) and attitudes toward public figures, groups, and policies. We employ a variety of methods to combat the selection bias inherent in such relationships. We find that listening to Limbaugh is independently associated with attitudes toward issues that Limbaugh emphasizes but shows no independent covariance with attitudes toward salient issues that Limbaugh neglects. Moreover, Limbaugh listening independently corresponds to greater negativity toward Ross Perot, a figure for whom affect cannot be accurately predicted from individual party identification or ideology. Finally, regular listening to Limbaugh predicts substantial change in attitudes from 1994 to 1996, but the effects are substantially muted when the Limbaugh message is positive rather than negative.

Journal Article↗
PubMed2000

Diagnosis of cutaneous leishmaniasis in Colombia: the sampling site within lesions influences the sensitivity of parasitologic diagnosis.

Parasitologic confirmation of cutaneous leishmaniasis is obligatory before chemotherapy can be considered. Direct microscopic examination of scrapings taken from indurated borders of ulcers has been routinely used as primary method of diagnosis. In this report we compared the sensitivity of examination of dermal scrapings taken from the bottoms of ulcers (BDS) with that of dermal scrapings taken from indurated active margins of lesions (MDS) in a total of 115 patients. The sensitivities of the microscopic examination were 90.4 and 78.3% for BDS and MDS samples, respectively. When the PCR method was used with a group of 40 patients, we also observed a higher sensitivity when BDS samples were examined (80.8% in BDS samples versus 57.7% in MDS samples). The improvement of the diagnostic sensitivity in the BDS samples appears to be related to the higher parasite load and more easily detectable morphology of amastigotes in the centers of the ulcers. Other parasitologic diagnostic methods, such as culture and histopathologic examination of biopsies, are less sensitive (67.5 and 64.3%, respectively). Aspirate culture, however, was shown to be the most sensitive method for the diagnosis of patients with chronic ulcers. When microscopic examinations of both MDS and BDS samples are combined, the sensitivity of diagnosis may rise up to 94%. We therefore recommend this method as a primary routine procedure for diagnosis of cutaneous leishmaniasis.

Animals↗
PubMed2000

Fetal and childhood growth and hypertension in adult life.

The association between low birth weight and raised blood pressure has been extensively replicated. Little is known about the way childhood growth modifies the effects of low birth weight. We report on the fetal and childhood growth of 1958 men and women who received treatment for hypertension and belong to a cohort of 7086 people born in Helsinki, Finland, during 1924-1933. As expected, the men and women who developed hypertension had low birth weight (P=0.002). They were also shorter in body length at birth (P=0.02). After birth they experienced accelerated growth, so that by 7 years their heights and weights were approximately average. In a simultaneous regression, both birth length and tall height had statistically significant although opposing effects on hypertension (P=0.003 for birth length and 0.009 for height at 7 years). Accelerated postnatal growth was associated with better childhood living conditions. Children who later developed both hypertension and type 2 diabetes, rather than hypertension alone, had small placental size as well as small body size at birth, and their accelerated postnatal growth continued beyond 7 years. We suggest that hypertension may originate through retarded growth in utero followed by accelerated postnatal growth as a result of good living conditions. Retarded fetal growth leads to permanently reduced cell numbers in the kidney and other tissues, and subsequent accelerated growth may lead to excessive metabolic demand on this limited cell mass.

Adolescent↗
PubMed2000

Fetal growth and early postnatal growth are related to blood pressure in adults.

It is commonly agreed that birth weight is associated with blood pressure in adults. However, not much is known about birth length, ponderal index, and early postnatal growth, whose effects on adult blood pressure, if any, can affect the interpretation of the birth weight-blood pressure association. This study examined the association between fetal growth, early postnatal growth, and blood pressure in Chinese adults. One hundred twenty-two subjects born in Hong Kong in 1967 were followed from birth to age 30 years. Multiple linear regression was used to analyze the association between size at birth, postnatal changes in body size, and systolic and diastolic blood pressure at age 30 years. Having adjusted for potential confounders and each other explanatory variable, it is found that birth length standard deviation score (regression coefficient or beta=-3.2), ponderal index at birth (beta=-1.8), and postnatal changes in ponderal index from age 6 months to 18 months (beta=-2.2) were inversely associated with systolic blood pressure (each P<0.05). Postnatal changes in length standard deviation score were not significantly associated with systolic blood pressure. Birth length standard deviation score was inversely associated with diastolic blood pressure at age 30 years (beta=-2.6; P<0.05). Other anthropometric variables were not associated with diastolic blood pressure. The results support the hypotheses that both fetal growth and early postnatal growth may have a long-term impact on blood pressure in adults. It also highlights the importance of differentiating length and weight for length.

Adolescent↗
PubMed2000

Isolation and expression of PASK, a serine/threonine kinase, during rat embryonic development, with special emphasis on the pancreas.

We report the isolation and characterization of a serine/threonine kinase expressed during rat pancreas development. This kinase was cloned as part of a general screen using degenerate oligonucleotides to map expression of kinases and receptors during the course of pancreatic development. Sequence analysis showed it to be a member of the ste20-like serine/threonine kinase family. Northern blotting analysis against both fetal and adult tissues showed two transcripts, one of 2 kb and the other of 4 kb. The ratio of transcript expression varied with the tissue. In situ hybridization analysis showed that this gene is expressed in the early gut and pancreatic epithelium. By embryonic Day 15, the transcript is localized to cells that will eventually become exocrine in nature. In situ hybridization analysis also demonstrated high levels of expression in the choroid plexus, the developing myocardium, kidney, CNS, dorsal root ganglia, and testes. In addition, a search of the EST database revealed a related human kinase not previously described.

Amino Acid Sequence↗
PubMed2000

Cancer risk estimates for family members of a population-based family registry for breast and ovarian cancer.

Population-based breast and ovarian cancer family registries can facilitate studies to evaluate genetic and environmental factors in the etiology of these malignancies. The purpose of this study is to describe what is, as far as we know, the first population-based breast and ovarian cancer family registry and to estimate breast and ovarian cancer risk in relatives of breast and ovarian cancer probands. Population-based consecutive incident cases of breast and ovarian cancer were invited to participate in the University of California, Irvine breast and ovarian family registry. In this study, we report data on 1567 breast cancer and 328 ovarian cancer probands. The operational components of this family registry include enrollment of probands, family history interviewing, confidentiality, pathology, verification and review, biospecimen bank, statistical/genetic analysis, and special studies on positional cloning of known genes. All of the components are tracked through the University of California, Irvine Genetic Research Information System. In non-Hispanic-white breast cancer probands, relative risk (RR) of breast cancer in mothers and sisters is significantly elevated [RR = 1.7 and 95% confidence interval (CI) = 1.4-2.0 and RR = 2.8 and 95% CI = 2.3-3.3, respectively]. In families of ovarian cancer probands, mothers are at increased risk of ovarian cancer (RR = 4.6; 95% CI, 2.1-8.7). RR of breast cancer in mothers of Hispanic breast cancer probands is significantly elevated (RR = 4.9; 95% CI, 2.6-8.5). No elevation of breast or ovarian cancer risk was observed among relatives of Asian probands. In general, there is a decrease in RR among mothers and sisters with increase in age of onset of probands. In second-degree relatives and first cousins, the breast cancer hazards ratios increase with increase in the number of affected first-degree relatives and decrease with increase in age at onset of the proband.

Adult↗
PubMed1999

Characterisation of kinetoplast DNA minicircles from Herpetomonas samuelpessoai.

In this study, we have sequenced more than 100 clones of minicircle DNA from Herpetomonas samuelpessoai. An unusual amplification approach was developed to amplify minicircle DNA by using a pair of complementary primers designed from a universal stretch of minicircle sequence. Sequence analysis shows that the kinetoplast minicircles in Herpetomonas with a size of 1.3 kb are organised into two conserved regions and two variable regions which are located 180 degrees apart. The potential gRNA genes are encoded in variable regions of minicircle approximately 360 bp from CSB-3 (conserved sequence block 3). A conserved upstream sequence located 30 nt before the gRNA genes was identified and is related to the gRNA genes in sequence organisation. A potential role(s) of this sequence in gRNA transcription is discussed.

Animals↗