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1.
BJOG ; 127(10): 1200-1209, 2020 09.
Article in English | MEDLINE | ID: mdl-32145139

ABSTRACT

OBJECTIVE: To examine the associations of maternal and child overweight status across multiple time-points with liver fat content in the offspring during young adulthood. DESIGN: Cohort study. SETTING: ELEMENT Cohort in Mexico City. POPULATION: Pregnant women with singleton births (n = 97). METHODS: We quantified hepatic triglyceride content (liver fat content) by proton magnetic resonance spectroscopy (1H MRS) and conventional T2-weighted MRIs (3T scanner) in 97 young adults from the ELEMENT birth cohort in Mexico City. Historical records of the cohort were used as a source of pregnancy, and childhood and adolescence anthropometric information, overweight and obesity (OWOB) were defined. Adjusted structural equation models were run to identify the association between OWOB in different life stages with liver fat content (log-transformed) in young adulthood. MAIN OUTCOME: Maternal OWOB at the time of delivery was directly and indirectly associated with the liver fat content in the offspring at young adulthood. RESULTS: Seventeen percent of the participants were classified as having NAFLD. We found a strong association of OWOB between all periods assessed. Maternal OWOB at time of delivery (ß = 1.97, 95% CI 1.28-3.05), and OWOB status in the offspring at young adulthood (ß = 3.17, 95% CI 2.10-4.77) were directly associated with the liver fat content in the offspring. Also, maternal OWOB was indirectly associated with liver fat content through offspring OWOB status. CONCLUSION: We found that maternal OWOB status is related to fatty liver content in the offspring as young adults, even after taking into account OWOB status and lifestyle factors in the offspring. TWEETABLE ABSTRACT: There was an association between pre-pregnancy overweight and the development of NAFLD in adult offspring.


Subject(s)
Non-alcoholic Fatty Liver Disease/epidemiology , Obesity/epidemiology , Pregnancy Complications/epidemiology , Adolescent , Adult , Birth Weight , Body Mass Index , Case-Control Studies , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Mexico/epidemiology , Non-alcoholic Fatty Liver Disease/etiology , Pregnancy , Prenatal Exposure Delayed Effects/epidemiology , Triglycerides/analysis , Young Adult
3.
Clin Exp Allergy ; 48(10): 1297-1304, 2018 10.
Article in English | MEDLINE | ID: mdl-29808611

ABSTRACT

BACKGROUND: Identifying metabolomic profiles of children with asthma has the potential to increase understanding of asthma pathophysiology. OBJECTIVE: To identify differences in plasma metabolites between children with and without current asthma at mid-childhood. METHODS: We used untargeted mass spectrometry to measure plasma metabolites in 237 children (46 current asthma cases and 191 controls) in Project Viva, a birth cohort from eastern Massachusetts, USA. Current asthma was assessed at mid-childhood (mean age 8.0 years). The ability of a broad spectrum metabolic profile to distinguish between cases and controls was assessed using partial least squares discriminant analysis. We used logistic regression models to identify individual metabolites that were differentially abundant by case-control status. We tested significant metabolites for replication in 411 children from the VDAART clinical trial. RESULTS: There was no evidence of a systematic difference in the metabolome of children reporting current asthma vs. healthy controls according to partial least squares discriminant analysis. However, several metabolites were associated with odds of current asthma at a nominally significant threshold (P < .05), including a metabolite of nicotinamide (N1-Methyl-2-pyridone-5-carboxamide (Odds Ratio (OR) = 2.8 (95% CI 1.1-8.0)), a pyrimidine metabolite (5,6-dihydrothymine (OR = 0.4 (95% CI 0.2-0.9)), bile constituents (biliverdin (OR = 0.4 (95%CI 0.1-0.9), taurocholate (OR = 2.0 (95% CI 1.2-3.4)), two peptides likely derived from fibrinopeptide A (ORs from 1.6 to 1.7), and a gut microbiome metabolite (p-cresol sulphate OR = 0.5 (95% CI 0.2-0.9)). The associations for N1-Methyl-2-pyridone-5-carboxamide and p-cresol sulphate replicated in the independent VDAART population (one-sided P values = .03-.04). CONCLUSIONS AND CLINICAL RELEVANCE: Current asthma is nominally associated with altered levels of several metabolites, including metabolites in the nicotinamide pathway, and a bacterial metabolite derived from the gut microbiome.


Subject(s)
Asthma/blood , Biomarkers/blood , Metabolome , Metabolomics , Asthma/diagnosis , Asthma/immunology , Case-Control Studies , Child , Chromatography, Liquid , Female , Humans , Male , Mass Spectrometry , Metabolomics/methods , Odds Ratio
4.
Nutr Metab Cardiovasc Dis ; 24(6): 614-22, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24477006

ABSTRACT

BACKGROUND AND AIMS: DNA methylation of repetitive elements may explain the relations between dietary intake, hyperhomocysteinemia, and cardiovascular disease risk. We investigated associations of methyl micronutrient intake and plasma total homocysteine with LINE-1 and Alu methylation in a cross-sectional study of 987 adults aged 45-84 y who participated in the Multi-Ethnic Study of Atherosclerosis (MESA) Stress Study. METHODS AND RESULTS: DNA methylation was estimated using pyrosequencing technology. A 120-item food frequency questionnaire was used to ascertain daily intake of folate, vitamin B12, vitamin B6, zinc, and methionine. Plasma total homocysteine was quantified using a fluorescence polarization immunoassay. Associations of micronutrient intake and homocysteine with LINE-1 and Alu methylation were examined using linear regression. Adjusted differences in %5-methylated cytosines (%5 mC) were examined by categories of predictors using multivariable linear regression models. Intake of methyl-donor micronutrients was not associated with DNA methylation. After adjustment for covariates, each 3 µmol/L increment of homocysteine corresponded with 0.06 (-0.01, 0.13) %5 mC higher LINE-1 methylation. Additionally, BMI was positively associated with LINE-1 methylation (P trend = 0.03). Participants with BMI ≥ 40 kg/m² had 0.35 (0.03, 0.67) %5 mC higher LINE-1 than those with normal BMI. We also observed a 0.10 (0.02, 0.19) %5 mC difference in Alu methylation per 10 cm of height. These associations did not differ by sex. CONCLUSION: Dietary intake of methyl-donor micronutrients was not associated with measures of DNA methylation in our sample. However, higher BMI was related to higher LINE-1 methylation, and height was positively associated with Alu methylation.


Subject(s)
Alu Elements , Atherosclerosis/etiology , DNA Methylation , Diet/adverse effects , Homocysteine/blood , Hyperhomocysteinemia/etiology , Long Interspersed Nucleotide Elements , Aged , Aged, 80 and over , Atherosclerosis/complications , Atherosclerosis/epidemiology , Atherosclerosis/metabolism , Biomarkers/blood , Body Height , Body Mass Index , Cross-Sectional Studies , Female , Humans , Hyperhomocysteinemia/complications , Hyperhomocysteinemia/epidemiology , Hyperhomocysteinemia/metabolism , Los Angeles/epidemiology , Male , Micronutrients/deficiency , Micronutrients/metabolism , Middle Aged , New York City/epidemiology , Obesity, Morbid/complications , Risk Factors
5.
QJM ; 112(11): 841-846, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31286139

ABSTRACT

BACKGROUND: The relationship between gout medication use and cataract development is controversial. Moreover, limited clinical studies have evaluated this relationship. AIM: To assess the effects of colchicine, allopurinol and benzbromarone on the risk of cataract in patients with gout. DESIGN: Population-based nested case-control study. METHODS: We enrolled 7900 patients who had received a new diagnosis of cataract >3 years after gout diagnosis into the study group and 33 475 patients who did not receive a diagnosis of cataract into the control group by matching for age, sex and the year of gout diagnosis at a ratio of 1:1. We used World Health Organization's defined daily dose (DDD) as a measure to assess the dosage of colchicine, allopurinol and benzbromarone exposure. Logistic regression was used to estimate crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the risk of cataract. RESULTS: The risk of cataract significantly increased in patients who received colchicine at a cumulative DDD of ≥66.5 (OR = 1.17, 95% CI = 1.01-1.36, P = 0.041). In the age-stratified analysis, patients with gout aged >60 years had a higher risk of cataract (OR = 1.27, 95% CI = 1.06-1.53, P = 0.011) than did patients aged <60 years. Allopurinol and benzbromarone had no association with cataract. CONCLUSIONS: In this population-based nested case-control study, we observed that colchicine use increased the risk of cataract in patients with gout, especially in those aged >60 years who received colchicine at a cumulative DDD of >66.5.


Subject(s)
Cataract/chemically induced , Colchicine/adverse effects , Gout Suppressants/adverse effects , Gout/drug therapy , Adult , Age Factors , Aged , Aged, 80 and over , Allopurinol/therapeutic use , Benzbromarone/therapeutic use , Case-Control Studies , Cataract/epidemiology , Colchicine/administration & dosage , Databases, Factual , Female , Gout/complications , Gout Suppressants/administration & dosage , Humans , Logistic Models , Male , Middle Aged , National Health Programs , Risk Factors , Taiwan , Young Adult
6.
J Dev Orig Health Dis ; 9(4): 432-441, 2018 08.
Article in English | MEDLINE | ID: mdl-29665872

ABSTRACT

This study investigates relations of maternal N-3 and N-6 polyunsaturated fatty acids (PUFA) intake during pregnancy with offspring body mass index (BMI), height z-score and metabolic risk (fasting glucose, C-peptide, leptin, lipid profile) during peripuberty (8-14 years) among 236 mother-child pairs in Mexico. We used food frequency questionnaire data to quantify trimester-specific intake of N-3 alpha-linolenic acid, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); N-6 linoleic acid and arachidonic acid (AA); and N-6:N-3 (AA:EPA+DHA), which accounts for the fact that the two PUFA families have opposing effects on physiology. Next, we used multivariable linear regression models that accounted for maternal education and parity, and child's age, sex and pubertal status, to examine associations of PUFA intake with the offspring outcomes. In models where BMI z-score was the outcome, we also adjusted for height z-score. We found that higher second trimester intake of EPA, DHA and AA were associated with lower offspring BMI and height z-score. For example, each 1-s.d. increment in second trimester EPA intake corresponded with 0.25 (95% CI: 0.03, 0.47) z-scores lower BMI and 0.20 (0.05, 0.36) z-scores lower height. Accounting for height z-score in models where BMI z-score was the outcome attenuated estimates [e.g., EPA: -0.16 (-0.37, 0.05)], suggesting that this relationship was driven by slower linear growth rather than excess adiposity. Maternal PUFA intake was not associated with the offspring metabolic biomarkers. Our findings suggest that higher PUFA intake during mid-pregnancy is associated with lower attained height in offspring during peripuberty. Additional research is needed to elucidate mechanisms and to confirm findings in other populations.


Subject(s)
Adiposity/physiology , Body Height , Body Mass Index , Fatty Acids, Omega-3/administration & dosage , Fatty Acids, Omega-6/administration & dosage , Obesity/prevention & control , Prenatal Exposure Delayed Effects/prevention & control , Adiposity/drug effects , Adolescent , Adult , Child , Female , Humans , Infant, Newborn , Male , Middle Aged , Obesity/metabolism , Pregnancy , Prospective Studies , Young Adult
7.
Pediatr Obes ; 12(1): 48-57, 2017 02.
Article in English | MEDLINE | ID: mdl-26843357

ABSTRACT

BACKGROUND: Prenatal exposure to traffic pollution has been associated with faster infant weight gain, but implications for cardiometabolic health in later childhood are unknown. METHODS: Among 1418 children in Project Viva, a Boston-area pre-birth cohort, we assessed anthropometric and biochemical parameters of cardiometabolic health in early (median age 3.3 years) and mid- (median age 7.7 years) childhood. We used spatiotemporal models to estimate prenatal and early life residential PM2.5 and black carbon exposure as well as traffic density and roadway proximity. We performed linear regression analyses adjusted for sociodemographics. RESULTS: Children whose mothers lived close to a major roadway at the time of delivery had higher markers of adverse cardiometabolic risk in early and mid-childhood. For example, total fat mass was 2.1 kg (95%CI: 0.8, 3.5) higher in mid-childhood for children of mothers who lived <50 m vs. ≥200 m from a major roadway. Black carbon exposure and traffic density were generally not associated with cardiometabolic parameters, and PM2.5 exposure during the year prior was paradoxically associated with improved cardiometabolic profile. CONCLUSIONS: Infants whose mothers lived close to a major roadway at the time of delivery may be at later risk for adverse cardiometabolic health.


Subject(s)
Air Pollutants/adverse effects , Air Pollution/adverse effects , Environmental Exposure/adverse effects , Metabolic Syndrome/epidemiology , Air Pollutants/analysis , Biomarkers/analysis , Boston , Child , Child, Preschool , Cohort Studies , Female , Humans , Infant , Male , Metabolic Syndrome/etiology , Pregnancy , Prenatal Exposure Delayed Effects , Prospective Studies , Regression Analysis
8.
Obes Sci Pract ; 2(4): 471-476, 2016 12.
Article in English | MEDLINE | ID: mdl-28090353

ABSTRACT

OBJECTIVE: This study aims to investigate relations of serum leptin at age 4 with development of adiposity and linear growth during 3 years of follow-up among 75 Greek children and to identify serum metabolites associated with leptin at age 4 and to characterize their associations with adiposity gain and linear growth. METHODS: Linear regression models that accounted for maternal age, education and gestational weight gain and child's age and sex were used to examine associations of leptin and leptin-associated metabolites measured at age 4 with indicators of adiposity and linear growth at age 7. RESULTS: Each 1-unit increment in natural log-(ln)-transformed leptin corresponded with 0.33 (95% CI: 0.10, 0.55) units greater body mass index-for-age z-score gain during follow-up. Likewise, higher levels of the leptin-associated metabolites methylmalonyl-carnitine and glutaconyl-carnitine corresponded with 0.14 (95% CI: 0.01, 0.27) and 0.07 (95% CI: -0.01, 0.16) units higher body mass index-for-age z-score gain, respectively. These relationships did not differ by sex or baseline weight status and were independent of linear growth. CONCLUSIONS: These findings suggest that leptin, methylmalonyl-carnitine and possibly glutaconyl-carnitine are associated with weight gain during early childhood. Future studies are warranted to confirm these findings in other populations.

9.
Eur J Clin Nutr ; 69(2): 167-72, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25271016

ABSTRACT

BACKGROUND/OBJECTIVES: Studies in adults indicate that dietary polyunsaturated fatty acid (PUFA) composition may play a role in development of adiposity. Because adipocyte quantity is established between late childhood and early adolescence, understanding the impact of PUFAs on weight gain during the school-age years is crucial to developing effective interventions. SUBJECTS/METHODS: We quantified N-3 and N-6 PUFAs in serum samples of 668 Colombian schoolchildren aged 5-12 years at the time of recruitment into a cohort study, using gas-liquid chromatography. Serum concentrations of N-3 (alpha-linolenic acid (ALA), eicosapentaenoic acid, docosahexaenoic acid) and N-6 PUFAs (linoleic acid, gamma-linolenic acid, dihomo-gamma-linolenic acid, arachidonic acid) were determined as percentage total fatty acids. Children's anthropometry was measured annually for a median of 30 months. We used mixed-effects models with restricted cubic splines to construct population body mass index-for-age z-score (BAZ) growth curves for age- and sex-specific quartiles of each PUFA. RESULTS: N-3 ALA was inversely related to BAZ gain after adjustment for sex, baseline age and weight status, as well as household socioeconomic level. Estimated BAZ change between 6 and 14 years among children in the highest quartile of ALA compared with those in the lowest quartile was 0.45 (95% confidence interval: 0.07, 0.83) lower (P-trend=0.006). CONCLUSIONS: N-3 ALA may be protective against weight gain in school-age children. Whether improvement in PUFA status reduces adiposity in pediatric populations deserves evaluation in randomized trials.


Subject(s)
Body Mass Index , Diet , Fatty Acids/blood , Nutritional Status , Pediatric Obesity/prevention & control , Weight Gain/drug effects , alpha-Linolenic Acid/blood , Adiposity/drug effects , Child , Child, Preschool , Cohort Studies , Colombia , Dietary Fats/blood , Dietary Fats/pharmacology , Dietary Fats/therapeutic use , Fatty Acids/pharmacology , Fatty Acids/therapeutic use , Female , Humans , Male , Pediatric Obesity/blood , alpha-Linolenic Acid/pharmacology , alpha-Linolenic Acid/therapeutic use
10.
J Dev Orig Health Dis ; 6(2): 65-78, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25631626

ABSTRACT

In this review, we discuss the potential role of metabolomics to enhance understanding of obesity-related developmental origins of health and disease (DOHaD). We first provide an overview of common techniques and analytical approaches to help interested investigators dive into this relatively novel field. Next, we describe how metabolomics may capture exposures that are notoriously difficult to quantify, and help to further refine phenotypes associated with excess adiposity and related metabolic sequelae over the life course. Together, these data can ultimately help to elucidate mechanisms that underlie fetal metabolic programming. Finally, we review current gaps in knowledge and identify areas where the field of metabolomics is likely to provide insights into mechanisms linked to DOHaD in human populations.


Subject(s)
Metabolomics , Obesity/etiology , Animals , Humans , Obesity/metabolism
11.
J Formos Med Assoc ; 91(6): 601-7, 1992 Jun.
Article in English | MEDLINE | ID: mdl-1358346

ABSTRACT

In order to decrease complications following incomplete hemostasis, we tried to make a safe, efficient and highly concentrated fibrin glue by thawing single-donor fresh frozen plasma. Using a unique animal model, in which arterial bleeding was created, fibrin glue and some related hemostatic agents were tested to evaluate their hemostatic effectiveness. The results demonstrated that: 1) the concomitant use of cryoprecipitate-thrombin tissue glue with adjuvant (aprotinin or calcium chloride) had a better hemostatic effect than the use of cryoprecipitate-thrombin tissue glue alone (p < 0.05); 2) impregnation of fibrin glue with a suitable vehicle was advisable to accelerate the coagulation plug formation and to enhance the mechanical strength of the adhesive plug; 3) Gelform, used as a vehicle to hold the fibrin glue, had a more efficient hemostatic effect than gauze, collagen fleece and Surgicel (p < 0.05); 4) systemic heparinization attenuated the effectiveness of the hemostatic agents and aggravated the bleeding problem, but a low hematocrit level did not; 5) fibrin glue had its own limitations, especially under systemic heparinization, on hemostatic effectiveness in a high-pressure system. Understanding the characteristics of fibrin glue, as mentioned above, definitely improved the hemostatic effectiveness of the glue, especially after failure of the usual methods of controlling bleeding.


Subject(s)
Fibrin Tissue Adhesive/therapeutic use , Hemostasis, Surgical/methods , Animals , Dogs , Hematocrit , Hemodilution , Heparin/therapeutic use
12.
Eur J Clin Nutr ; 67(6): 646-51, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23462945

ABSTRACT

BACKGROUND: Studies regarding the role of iron on linear growth have yielded heterogeneous results. Some trials indicate that iron supplementation of iron-replete infants leads to slower-length gain. However, little is known of the relation between iron status and linear growth in school-age children. METHODS: We quantified plasma ferritin, mean corpuscular volume (MCV), and hemoglobin in 2714 children aged 5-12 years at recruitment into a cohort study. Height was measured periodically for a median of 30 months. Height-for-age Z-scores (HAZ) were calculated using the World Health Organization growth reference. Mixed effects models with restricted cubic splines were used to construct population HAZ-for-age growth curves for sex- and age-specific quartiles of each iron status indicator. RESULTS: Ferritin and MCV were each inversely related to attained HAZ among boys after the adjustment for baseline age, baseline body mass index-for-age Z-score and socioeconomic status. There was a decreasing monotonic relation between quartiles of ferritin and estimated change in HAZ from ages 6 to 14 years (P trend=0.001); boys in the 4th quartile experienced a HAZ change that was 0.46 Z lower than that of boys in the 1st quartile (P=0.0006). Similarly, we observed smaller HAZ change among boys in the highest quartile of MCV in comparison with those in the 1st quartile (P trend=0.001). Hemoglobin was not related to linear growth in boys. None of the iron-status indicators were associated with linear growth in girls. CONCLUSIONS: Higher iron status, as indicated by ferritin and MCV, is related to slower linear growth in iron-replete school-age boys.


Subject(s)
Body Height , Child Development , Growth Disorders/etiology , Iron, Dietary/adverse effects , Nutritional Status , Anemia, Iron-Deficiency/blood , Anemia, Iron-Deficiency/epidemiology , Child , Child, Preschool , Cohort Studies , Colombia/epidemiology , Female , Follow-Up Studies , Food, Fortified/adverse effects , Growth Disorders/epidemiology , Growth Disorders/physiopathology , Humans , Iron Overload/blood , Iron Overload/epidemiology , Iron Overload/etiology , Iron Overload/physiopathology , Iron, Dietary/administration & dosage , Longitudinal Studies , Male , Nutrition Policy , Prevalence , Prospective Studies , Severity of Illness Index , Sex Characteristics
15.
Eur J Clin Chem Clin Biochem ; 31(7): 413-8, 1993 Jul.
Article in English | MEDLINE | ID: mdl-8399780

ABSTRACT

The effects of hypothermia on the intracellular pH of human erythrocytes were studied non-invasively using 31P NMR spectroscopy and the endogenous phosphorus-containing compounds glycerate 2,3-bisphosphate and inorganic phosphate. Specifically, the pH dependence of the 31P NMR chemical shifts of these compounds was used to measure the intracellular pH at 25 and 37 degrees C. The possibility of a non-pH-dependent change on the chemical shifts of the 2-P and 3-P resonances of glycerate 2,3-bisphosphate due to the presence of paramagnetic deoxy-haemoglobin (i.e., a pseudo-contact interaction) was investigated and found to have negligible effect under the present experimental conditions. The most probable reasons for this are that the deoxy-haemoglobin concentration was too small and/or the glycerate 2,3-bisphosphate does not get sufficiently close to the paramagnetic centre to be affected. The change in intracellular pH with temperature was consistent with that predicted by the alphastat hypothesis.


Subject(s)
Cold Temperature , Diphosphoglyceric Acids/blood , Erythrocytes/chemistry , 2,3-Diphosphoglycerate , Carbon Monoxide/pharmacology , Hemoglobins/chemistry , Humans , Hydrogen-Ion Concentration , Magnetic Resonance Spectroscopy
16.
Am J Physiol ; 266(3 Pt 2): R1008-15, 1994 Mar.
Article in English | MEDLINE | ID: mdl-8160849

ABSTRACT

The alphastat hypothesis states that intracellular acid-base status is regulated to maintain constancy of the fractional dissociation of intracellular protein and enzyme imidazole-histidine (alpha-imidazole). A major drawback of this theory has been the lack of a means to directly measure alpha-imidazole in intact animals. We developed a method for directly measuring alpha-imidazole in intact unanesthetized animals using 1H-nuclear magnetic resonance spectroscopy (NMR). We measured carnosine alpha-imidazole of white skeletal muscle from intact unanesthetized newts at three body temperatures (10, 20, and 30 degrees C). alpha-Imidazole remained constant, approximately 0.56, with alterations in body temperature, whereas intracellular pH (pHi) changed significantly (-0.015 U/degrees C), affirming the validity of the imidazole alphastat hypothesis for this tissue. This method was also used to determine the pK values of the imidazole moiety of carnosine and the imidazole moiety alone over a temperature (T) range 4-40 degrees C. The pK values of carnosine differed from those of imidazole, but the delta pK/delta T was the same. pHi was also determined using 31P-NMR and found to be the same as that calculated from carnosine alpha-imidazole values. Therefore Pi and carnosine share a similar pHi environment. We describe a novel technique to directly measure alpha-imidazole in intact tissue.


Subject(s)
Imidazoles/metabolism , Magnetic Resonance Spectroscopy , Animals , Carnosine/metabolism , Hydrogen-Ion Concentration , Intracellular Membranes/metabolism , Models, Biological , Muscles/metabolism , Protons , Salamandridae , Solutions , Temperature
17.
Biophys J ; 80(6): 2493-504, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11371428

ABSTRACT

A simplified pore-to-pore hopping model for the two-phase diffusion problem is developed for the analysis of the pulsed gradient spin echo (PGSE) attenuation of water diffusion in the condensed cell suspension systems. In this model, the two phases inside and outside the cells are treated as two different kinds of pores, and the spin-bearing molecules perform hopping diffusion between them. The size and the orientations of those two respective pores are considered, and then the diffraction pattern of the PGSE attenuation may be well simulated. Nevertheless, the intensity of the characteristic peak decreases with increasing membrane permeability, from which the exchange time may be estimated. We then analyze the experimental 1H PGSE results of the erythrocytes suspension system. The water-residence lifetime in the erythrocyte is obtained to be 10 ms, which is the same as that estimated from the two-region approximation. Furthermore, the PGSE attenuation curve of addition of p-Chloromercuribenzenesulfonate (p-CMBS) is also discussed. It predicts that the alignment of erythrocytes will become normal to the magnetic field direction after the addition of p-CMBS, and inspection using a light microscope confirms that result.


Subject(s)
Cell Membrane Permeability/physiology , Diffusion , Models, Biological , 4-Chloromercuribenzenesulfonate/pharmacology , Biological Transport , Cell Polarity/drug effects , Computer Simulation , Erythrocytes/chemistry , Erythrocytes/cytology , Erythrocytes/metabolism , Humans , Magnetic Resonance Spectroscopy , Magnetics , Microscopy , Water/metabolism
18.
Am J Physiol ; 265(5 Pt 2): R1162-7, 1993 Nov.
Article in English | MEDLINE | ID: mdl-8238619

ABSTRACT

The effect of acute alterations in body temperature (BT) on intracellular pH (pHi) and phosphate metabolites was assessed in white skeletal muscle of intact newts and lungless red-backed salamanders using 31P-nuclear magnetic resonance spectroscopy. pHi decreased with increasing BT in the tail muscle of both newts and lungless red-backed salamanders. The change in pH with change in temperature from 10 to 30 degrees C was -0.018 U/degrees C in newts and -0.041 U/degrees C in red backs. The calculated alpha-imidazole for skeletal muscle cytosol did not change (0.56) in newts from 10 to 30 degrees C but fell from 0.69 to 0.43 in red-backed salamanders. Phosphocreatine (PCr)/Pi fell and Pi/beta-ATP rose with increasing temperature in both newts and red backs; however, the change was much greater in red backs. Providing the red backs with O2 at 30 degrees C led to higher pH and alpha-imidazole, comparable to that of newts, along with increased PCr/Pi and lower Pi/beta-ATP. Thus newts maintain white skeletal muscle cell cytosol alpha-imidazole constant with changes in BT, whereas red backs apparently do not. However, at the BT of preference, red backs and newts maintain similar muscle pHi and alpha-imidazole. The method of gas exchange appears to strongly influence the ability of an animal to maintain its acid-base status over a range of temperatures, and our results suggest that behavioral regulation of BT may involve alpha-imidazole regulation as well.


Subject(s)
Acclimatization , Energy Metabolism , Hydrogen-Ion Concentration , Muscles/physiology , Notophthalmus viridescens/physiology , Salamandridae/physiology , Adenosine Triphosphate/metabolism , Animals , Magnetic Resonance Spectroscopy , Muscles/metabolism , Phosphates/metabolism , Phosphocreatine/metabolism , Species Specificity , Temperature
19.
Zhonghua Yi Xue Za Zhi (Taipei) ; 52(2): 120-4, 1993 Aug.
Article in English | MEDLINE | ID: mdl-8402366

ABSTRACT

The development of adult respiratory distress syndrome (ARDS) can be associated with a variety of clinical disorders. Pulmonary cryptococcosis occurring in immunocompromised patients has been reported with increasing frequency because of the rapidly rising number of immunocompromised hosts and the improvement in diagnostic techniques. But pulmonary cryptococcosis causing ARDS in immunocompetent patients has not, to present knowledge, been described. Here a rare case of pulmonary cryptococcosis is reported in an immunocompetent host who developed adult respiratory distress syndrome. The clinical course, radiologic patterns, methods of diagnosis and treatment are reviewed.


Subject(s)
Cryptococcosis/complications , Lung Diseases, Fungal/complications , Respiratory Distress Syndrome/etiology , Adult , Cryptococcosis/drug therapy , Cryptococcosis/immunology , Humans , Immunocompetence , Lung Diseases, Fungal/drug therapy , Lung Diseases, Fungal/immunology , Male
20.
Am J Respir Crit Care Med ; 160(4): 1319-23, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10508824

ABSTRACT

Current methods of preserving lung tissue for transplantation are inadequate. In this study, we tested whether the combination of hypothermia plus prostaglandin E(1) (PGE(1)) treatment would have synergistic attenuation on ischemia-reperfusion (I/R) lung injury. Isolated rat lung experiments with ischemia for 1 h then reperfusion for 1 h, were conducted using six different perfusates: (1) University of Wisconsin solution (UW) at 30 degrees C (n = 5), (2) UW at 22 degrees C (n = 5), (3) UW at 10 degrees C (n = 4), (4) UW+PGE(1) at 30 degrees C (n = 4), (5) UW+PGE(1) at 22 degrees C (n = 4), and (6) UW+PGE(1) at 10 degrees C (n = 4). Hemodynamic changes, lung weight gain, capillary filtration coefficients, and lung pathology were analyzed to evaluate the I/R injury. Compared with 30 degrees C UW, animals treated with 22 degrees C UW and 10 degrees C UW had less I/R lung injury, with the groups receiving 22 degrees C UW showing superior results to group receiving 10 degrees C UW. The addition of PGE(1) to UW solution produced more attenuation of I/R injury than did UW alone. Among the six groups, 10 degrees C UW+PGE(1) produced the most reduction of I/R injury. This study has shown that hypothermia can attenuate I/R injury with the optimal flushing temperature being near 22 degrees C. PGE(1) also has a protective effect on I/R. Furthermore, hypothermia and PGE(1) have synergistic attenuation of I/R lung injury. We propose that pulmonary artery flushed with cooling UW+PGE(1) might improve lung preservation and improve results in lung transplantation.


Subject(s)
Alprostadil/pharmacology , Hypothermia, Induced , Lung/pathology , Organ Preservation , Reperfusion Injury/pathology , Vasodilator Agents/pharmacology , Adenosine , Allopurinol , Animals , Capillary Permeability , Glutathione , Insulin , Lung/blood supply , Male , Organ Preservation Solutions , Organ Size , Pulmonary Circulation/drug effects , Pulmonary Wedge Pressure , Raffinose , Rats , Rats, Sprague-Dawley , Reperfusion Injury/prevention & control , Vascular Resistance
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