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1.
A variety of stimuli, including cytokines and adhesion to surfaces and matrix proteins, can regulate macrophage function, in part through changes in Ca2+-dependent second messengers. While fluctuation in in-tracellular Ca2+ is an important modulator of cellular activation, little attention has been paid to the roles of other ions whose cytoplasmic concentrations can be rapidly regulated by ion channels. To examine the role of ion channels in macrophage function, we undertook patch clamp studies of human culture-derived macrophages grown under serum-free conditions. The major ionic current in these cells was carried by an outwardly rectifying K+ channel, which had a single-channel conductance of 229 pS in symmetrical K+-rich solution and macroscopic whole-cell conductance of 9.8 nS. These channels opened infrequently in resting cells but were activated immediately by (i) adhesion of mobile cells onto a substrate, (ii) stretch applied to isolated membrane patches in Ca2+-free buffers, (iii) intracellular Ca2+ (EC50 of 0.4 m), and (iv) the cytokine IL-2. Furthermore, barium and 4-aminopyridine, blockers of this channel, altered the organization and structure of the cytoskeletal proteins actin, tubulin and vimentin. These cytoskeletal changes were associated with reversible alteration to the morphology of the cells. Thus, we have identified an outwardly rectifying K+ channel that appeared to be involved in cytokine and adherence-mediated macrophage activation, and in the maintenance of cytoskeletal integrity and cell shape.We thank Ken Wyse and Sue Bennett for excellent technical assistance. This work was supported by the National Health & Medical Research Council of Australia, the National Heart Foundation of Australia, the Clive & Vera Ramaciotti Foundation of Australia, the St Vincent's Hospital Clinic Foundation and a St Vincent's Hospital Research Grant.  相似文献   

2.
Summary A prospective randomized trial compared the administration of intrapleural plus intravenous Corynebacterium parvum (C. parvum) versus placebo in patients with resected Stage I and Stage II non-small cell bronchogenic carcinoma. Treatment consisted of 7 mg C. parvum injected into the pleural space and 7 mg C. parvum intravenously once between days 6 and 12 postoperatively and 7 mg intravenously every 3rd month during the 1st year. Intrapleural administration of 35 cc of saline served as the placebo and the flush after intrapleural C. parvum.Of the 303 patients entered into this study, 286 were evaluable, with an average follow-up time of 3.5 years. More complications, especially fever, were observed in patients receiving C. parvum. A fever greater than 38 °C was observed in 9% of the patients assigned to placebo and 76% of the patients assigned to C. parvum. There was no significant difference between the treatments with respect to disease-free interval or survival.M. Kaufmann, J. Stjernswärd**, A. Zimmermann (Ludwig Institute for Cancer Research, Bern Branch); K. Stanley**, M. Isley, M. Zelen (Frontier Science & Tech. Research Foundation, Brookline, MA, USA); C. Mouritzen, P. Paulsen, U. Henriques (Dept. of Thoracic and Cardiovascular Surgery and Institute of Pathology, Kommunehospital, Aarhus, Denmark); N. Konietzko, W. Maassen, W. Hartung, W. Wierich (Ruhrland Clinic, Essen-Heidhausen, and Pathology Institute, Ruhr-University, Bochum, FRG); P. Oehl (Innere Klinik und Poliklinik Tumorforschung, Essen, FRG); J. Vogt-Moykopf, H. Toomes, W. Hofmann (Rohrbach Hospital, Clinic for Thoracic Medicine and Pathology Institute, Heidelberg, FRG); F. Krause, R. Rios, R. Spanel (Klinik Löwenstein, Löwenstein, and Pathology Institute, Ulm, FRG); J. Orel, B. Hrabar, D. Ferluga, T. Rott (University Medical Center, Thoracic Surgery and Pathology, Ljubljana, Yugoslavia); H. A. Rostad, J. R. Vale, P. Lexow (Rikshospital, Oslo, Norway); S. Hagen, S. Birkeland (Ulleval Hospital, Oslo, Norway); T. Harbitz, R. Nissen-Meyer (Aker Hospital, Oslo, Norway); E. Aspevik, H. Engedal, A. Mykin (Haukeland Hospital, Bergen, Norway); V. O. Björk, L. Rodriguez, K. Böök, J. Willems (Karolinska Sjukhuset, Thoracic Surgical Clinic and Pathology Department, Stockholm, Sweden); E. Grädel, J. Hasse, P. Dalquen (Kantonsspital, Dept of Surgery, Div. of Cardiac & Thoracic Surgery & Pathology Institute, Basel, Switzerland); L. Eckmann, K. Hänni, K. Zimmermann (Tiefenauspital Surg. Clinic, Univ. of Bern, Switzerland); B. Nachbur, H. U. Würsten, H. Cottier, A. Zimmermann (Inselspital Dept. of Thoracic and Cardiovascular Surg. and Pathology Institute, Bern, Switzerland); W. Maurer, M. Kaufmann (Bürgerspital, Surgical Department, Solothurn, Switzerland); H. Denck, E. Zwintz, St. Wuketich (Krankenhaus der Stadt Wien-Lainz, I. Chir. Dept., and Path. Inst., Vienna, Austria); N. Pridun, H. Hackl (Pulmonologisches Zentrum der Stadt Wien, and Path. Inst., Vienna, Austria); E. Moritz, W. Schlick, H. Holzner (II. Chir. University Clinic and Path. Inst., Vienna, Austria); K. Karrer (Institute for Cancer Research, Vienna, Austria); R. G. Crispen (ITR-Biomedical Research, University of Illinois, Chicago, USA); D. S. Freestone, R. Bomford, M. T. Scott, T. Priestman, L. Toy (The Wellcome Research Laboratories, Beckenham, England)** Present address: Cancer Unit, World Health Organization, Geneva, Switzerland Offprint requests to: K. Stanley, Ludwig Institute for Cancer Research, Inselspital, CH-3010 Bern, SwitzerlandLudwig Lung Cancer Study Group:  相似文献   

3.

Objectives

Short and long sleep duration are associated with metabolic syndrome. However, there is limited research on the association between sleep quality and metabolic syndrome, and thus the aim of this study is to investigate this relationship.

Materials and Methods

The cross-sectional baseline data were collected from the decoded database of the Prevention Health Center of National Cheng Kung University Hospital from 2002 to 2006. The diagnosis of metabolic syndrome was according to the statement of the American Heart Association/National Heart, Lung, and Blood Institute. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). A higher global PSQI score indicates poorer sleep quality, and a global PSQI score greater than five differentiates poor from good sleepers.

Results

Of the 3,435 subjects recruited, 899 (26.2%) had metabolic syndrome. Subjects with metabolic syndrome had higher PSQI and prevalence of poor sleepers than those without metabolic syndrome. The multivariate lineal regression analysis showed that female gender, metabolic syndrome, sleep duration, snoring, alcohol drinking, and habitual exercise were independent predictors of PSQI. When substituting metabolic syndrome with the five components, hyperglycemia and low high-density lipoprotein cholesterol (HDL-C) were positively associated with PSQI. The multivariate logistic regression analyses showed that female gender, metabolic syndrome, sleep duration, and snoring were independently associated with being poor sleepers. Of the five components, only low HDL-C was an independent predictor of being poor sleepers.

Conclusions

Subjects with metabolic syndrome have higher global PSQI scores and a higher risk of being poor sleepers. Of the five components of metabolic syndrome, hyperglycemia and low HDL-C are independently associated with the global PSQI scores, while low HDL-C is an independent predictor of being poor sleepers.  相似文献   

4.
Objective: Impaired lung function is associated with obesity and insulin resistance. In this study, we investigated the relationship between metabolic syndrome and impaired lung function in adults. Research Methods and Procedures: A total of 46,514 subjects 20 years and over (21,669 men and 24,845 women, mean age = 37.3 ± 11.2 and 37.0 ± 11.3 years, respectively) were recruited from four nationwide MJ Health Screening Centers in Taiwan from 1998 to 2000. Metabolic syndrome was defined using the National Cholesterol Education Panel (NCEP) metabolic syndrome criteria or America Heart Association/National Heart Lung Blood Institute (AHA/NHLBI) criteria. The relationship between metabolic syndrome and lung function test was examined using multivariate logistic regression analysis. Results: The prevalence of impaired lung function was 11.1% in men and 14.0% in women. The prevalence of metabolic syndrome was 5.8% using NCEP criteria and 12.8% using AHA/NHLBI criteria. In multivariate logistic regression analysis with adjustment for age, gender, BMI, smoking, alcohol drinking, and physical activity, restrictive lung impairment was independently associated with increased risk of having metabolic syndrome (p < 0.01, odds ratios = 1.221 using NCEP criteria and 1.150 using AHA/NHLBI criteria). Discussion: Obesity and metabolic syndrome were associated with impaired lung function in adults in Taiwan. Our results imply that obesity and insulin resistance may be the common pathways underlying lung function impairment and metabolic syndrome. Moreover, lung function test may be applied as an additional evaluation for metabolic syndrome in a clinical setting.  相似文献   

5.
Summary The Southeastern Cancer Study Group conducted a randomized clinical trial in acute myeloblastic leukemia and the blastic phase of chronic myelocytic leukemia to compare: Two induction programs (Schedule A) cytosine arabinoside and 6-thioguanine or (Schedule B) cytosine arabinoside, 6-thioguanine and daunorubicin; two consolidation programs (Schedule C) continuation of induction programs at a reduced dose or (Schedule D) a combination of cyclophosphamide, methotrexate and vincristine; and two maintenance programs — (Schedule E) 1 month of BCG, followed by methotrexate or (Schedule F) methotrexate. Over a 3 year period 372 patients were entered and 295 were judged evaluable. None of 11 patients with blastic phase of chronic myelocytic leukemia responded. There were no significant differences between the schedules in the number of patients with acute myeloblastic leukemia achieving complete remissions (37%, Schedule A vs. 41% Schedule B). The relapse rates on consolidation were similar (43%, Schedule C and 39%, Schedule D). BCG significantly prolonged the duration of first remission following consolidation (P<0.05) from 13.0–23.9 weeks. Survival was not significantly prolonged (92.7 weeks vs. 71.7 weeks). There were no serious complications from BCG therapy. Contributors. The following members of the Southeastern Cancer Study Group participated in this study: John T. Carpenter, John R. Durant, Richard Gams, William J. Hammack, George A. Omura, Gayle Roberts, University of Alabama School of Medicine, Birmingham, Alabama; Harold Silberman, Donald S. Miller, Duke University School of Medicine, Durham, North Carolina; William B. Kremer, Durham Veterans Administration Hospital, Durham, North Carolina; Evert A. Bruckner, Lawrence E. Cooper, Charles C. Corley, Joseph E. Hardison, Charles M. Huguley, Jr., James Keller, Mason G. Robertson, John D. Schmale, Charles Vogel, W. R. Vogler, William H. Whaley, E. F. Winton, Emory University School of Medicine, Atlanta, Georgia; Chan Kon Chin, Guy Faguet, Claude-Starr Wright, Medical College of Georgia, Augusta, Georgia; Y. S. Ahn, Howard E. Lessner, University of Miami School of Medicine, Miami, Florida; Dov Gorshein, Scott Murphy, Presbyterian University of Pennsylvania Medical Center, Philadelphia, Pennsylvania; William E. Barry, Sharon P. Fischer, Rosaline R. Joseph, Richard V. Smalley, Temple University School of Medicine, Philadelphia, Pennsylvania; Virgil Loeb, Jr., Cary Presant, Edward Reinhard, Shabbir H. Safdar, Washington University School of Medicine, St. Louis, Missouri; Norman Maldonado, Enrique Velez-Garcia, University of Puerto Rico School of Medicine, San Juan, Puerto Rico; S. A. Gregory, William H. Knospe, Rush-Presbyterian-St. Luke's Medical Center, Chicago, Illinois; Stephen Krauss, University of Tennessee Memorial Research Center, Knoxville, Tennessee; Karl Tornyos, New Orleans Veterans Hospital, New Orleans, Louisiana; W. B. Forman, R. W. Kellermeyer, A. Rassiga, Case Western Reserve University School of Medicine, Cleveland, Ohio; William R. Arrowsmith, George Porter, Donald M. Samples, Ochsner Clinic, New Orleans, Louisiana; Lois W. Dow, Charles L. Neely, University of Tennessee School of Medicine, Memphis, Tennessee; G. O. Broun, Jr., St. Louis University School of Medicine, St. Louis, Missouri  相似文献   

6.
Adiponectin is an adipose‐secreted hormone with anti‐inflammatory properties mediated by inhibition of nuclear factor‐κB (NF‐κB) signaling. This study investigates whether fenofibrate alters adiponectin levels in patients with hypertriglyceridemia and the metabolic syndrome, and examines the association of adiponectin with circulating inflammatory markers and whole blood cytokine production. The effects of fenofibrate (160 mg/day) on adiponectin and other inflammatory markers were investigated in a 12‐week randomized, placebo‐controlled trial in 55 patients with hypertriglyceridemia (plasma triglycerides ≥1.7 mmol/l and <6.8 mmol/l), central obesity and other characteristics of the metabolic syndrome who were not receiving lipid‐altering therapies. In the fenofibrate group, adiponectin levels increased from 4.10 to 4.50 µg/ml (+7.7%); in the placebo group, adiponectin levels increased by 1.8%; (P = 0.0005). In multivariate models including age, gender, and waist circumference, there were inverse correlations between changes in adiponectin and vascular cell adhesion molecule‐1 (VCAM‐1) (r = −0.54, P < 0.0001) and intercellular adhesion molecule‐1 (ICAM‐1) (r = −0.57, P < 0.0001), and C‐reactive protein (CRP) (r = −0.40, P = 0.0041); lipopolysaccharide (LPS)‐stimulated production of tumor necrosis factor‐α (TNF‐α) (r = −0.30, P = 0.035), interleukin (IL)‐1β (r = −0.44, P = 0.0016), monocyte chemotactic protein‐1 (MCP‐1) (r = −0.46, P = 0.001), and macrophage inflammatory protein‐1α (MIP‐1α) (r = −0.45, P = 0.0012). Fenofibrate (160 mg/day) raised adiponectin levels in patients with hypertriglyceridemia and the metabolic syndrome. Changes in adiponectin were significantly and inversely associated with changes in multiple inflammatory markers. These data suggest that adiponectin may contribute to the anti‐inflammatory effects of fenofibrate.  相似文献   

7.
The purpose of this study was to compare the performance of six candidate urinary biomarkers, kidney injury molecule (KIM)-1, N-acetyl-β-D-glucosaminidase (NAG), neutrophil gelatinase-associated lipocalin (NGAL), interleukin (IL)-18, cystatin C and α-1 microglobulin, measured 2?h following cardiopulmonary bypass (CPB) for the early detection of acute kidney injury (AKI) in a prospective cohort of patients undergoing cardiac surgery. A total of 103 subjects were enrolled; AKI developed in 13%. Urinary KIM-1 achieved the highest area under-the-receiver-operator-characteristic curve (AUC 0.78, 95% confidence interval 0.64–0.91), followed by IL-18 and NAG. Only urinary KIM-1 remained independently associated with AKI after adjustment for a preoperative AKI prediction score (Cleveland Clinic Foundation score; p?=?0.02), or CPB perfusion time (p?=?0.006). In this small pilot cohort, KIM-1 performed best as an early biomarker for AKI. Larger studies are needed to explore further the role of biomarkers for early detection of AKI following cardiac surgery.  相似文献   

8.
The protective mechanisms by which some obese individuals escape the detrimental metabolic consequences of obesity are not understood. This study examined differences in body fat distribution and adipocytokines in obese older persons with and without metabolic syndrome. Additionally, we examined whether adipocytokines mediate the association between body fat distribution and metabolic syndrome. Data were from 729 obese men and women (BMI ≥30 kg/m2), aged 70–79 participating in the Health, Aging and Body Composition (Health ABC) study. Thirty‐one percent of these obese men and women did not have metabolic syndrome. Obese persons with metabolic syndrome had significantly more abdominal visceral fat (men: P = 0.04; women: P < 0.01) and less thigh subcutaneous fat (men: P = 0.09; women: P < 0.01) than those without metabolic syndrome. Additionally, those with metabolic syndrome had significantly higher levels of interleukin‐6 (IL‐6), tumor necrosis factor‐α (TNF‐α), and plasminogen activator inhibitor‐1 (PAI‐1) than individuals without metabolic syndrome. Per standard deviation higher in visceral fat, the likelihood of metabolic syndrome significantly increased in women (odds ratio (OR): 2.16, 95% confidence interval (CI): 1.59–2.94). In contrast, the likelihood of metabolic syndrome decreased in both men (OR: 0.56, 95% CI: 0.39–0.80) and women (OR: 0.49, 95% CI: 0.34–0.69) with each standard deviation higher in thigh subcutaneous fat. These associations were partly mediated by adipocytokines; the association between thigh subcutaneous fat and metabolic syndrome was no longer significant in men. In summary, metabolically healthy obese older persons had a more favorable fat distribution, characterized by lower visceral fat and greater thigh subcutaneous fat and a more favorable inflammatory profile compared to their metabolically unhealthy obese counterparts.  相似文献   

9.
Menstrual taboos are nearly ubiquitous and assume parallel forms in geographically distant populations, yet their function has baffled researchers for decades. This paper proposes that menstrual taboos are anticuckoldry tactics. By signaling menstruation, they may advertise female reproductive status to husbands, affines, and other observers. Females may therefore have difficulty in obfuscating the timing of the onset of pregnancy. This may have three consequences: (a) males are better able to assess their probabilities of paternity and to direct their parental investment toward genetic offspring; (b) adulterous pregnancies are more easily detected and penalized, enhancing sexual fidelity; and (c) males avoid marrying pregnant females by relying on menstruation as evidence of nonpregnancy. This hypothesis is tested with 29 months of field data on menstrual taboos among the Dogon of Mali. Key results include the following: (a) cuckoldry is a major Dogon concern, (b) menstrual huts advertise female reproductive status, (c) husbands impose the taboos upon their wives, (d) female defiance of the taboos is undetectable and probably rare, and (e) informants think that the taboos help husbands and patrilineages to avoid cuckoldry. Thus the anti-cuckoldry hypothesis provides helpful insight into the menstrual taboos of the Dogon and should be tested among other populations. This research was supported by The Evolution and Human Behavior Program at the University of Michigan (through Dick Alexander), the L.S.B. Leakey Foundation, and the National Science Foundation (BNS-8612291). Beverly Strassmann is a National Institutes of Health postdoctoral fellow at the Reproductive Sciences Program, University of Michigan. Her primary research interest is human evolutionary ecology, with recent emphasis on menstruation in natural fertility populations, the effect of polygyny on female fitness, and reproductive endocrinology.  相似文献   

10.
Book Reviews     
Michael Kearney. 1996. Reconceptualizing the Peasantry: Anthropology in Global Per‐spectwe. Boulder, Colorado: Westview Press. 210 pp.

Don Kulick &; Margaret Wiltson (eds). 1995. Taboo: Sex, Identity and Erotic Subjectivity in Anthropological Fieldwork. London/New York: Routledge. xvi + 283 pp.

Sandra Wallman et al. 1996. Kampala Women GettingBy: Well‐being in the Time of AIDS. London:James Currey Ltd. 246 pp.

Angelique Haugerud. 1995. The Culture of Politics in Modern Kenya. Cambridge: Cambridge University Press, xvi + 266 pp.

Mary Kay Vaughan. 1997. Cultural Politics in Revolution: Teachers, Peasants, and Schools in Mexico, 1920–1940. Tuscon: University of Arizona Press, xiii + 262 pp.

Robert J. Foster (ed.). 1995. Nation Making: Emergent Identities in Postcohnial Melanesia. Ann Arbor: University of Michigan Press, vi + 280 pp.

Tom G. Svensson. 1997. The Sámi and Their Land: The Sámi vs the Swedish Crown. Oslo: Novus forlag. 213 pp.

Pamela J. Asquith &; Arne Kalland (eds). 1997. Japanese Images of Nature: Cultural Perspectives. London: Curzon. 220 pp.  相似文献   

11.
Objective: To use standardized cut‐offs of body mass index (BMI), waist circumference, waist‐to‐hip ratio, and fasting insulin levels to predict the development of metabolic disorders and metabolic syndrome. Research Methods and Procedures: We performed an 8‐year follow‐up study of 628 non‐Hispanic whites and 1340 Mexican Americans, ages 25 to 64 years, from the second cohort of the San Antonio Heart Study. We defined metabolic disorders as dyslipidemia (triglycerides ≥2.26 mM or high‐density lipoprotein <0.91 mM in men and <1.17 mM in women), hypertension (blood pressure ≥140/≥90 mm Hg, or receiving antihypertensive medications), and type 2 diabetes (fasting glucose ≥7.0 mM, 2‐hour test glucose ≥11.1 mM, or receiving anti‐diabetic medications). People with at least two metabolic disorders were defined as having metabolic syndrome. Results: High waist‐to‐hip ratio and fasting insulin levels were significant predictors of developing metabolic syndrome. High anthropometric indices remained significant predictors of metabolic syndrome after adjusting for fasting insulin. Waist circumference, BMI, and insulin had similar areas under the receiver operating characteristic curves (0.74 to 0.76). Further multivariate analyses combining these indices showed minimal increase in prediction. Of subjects who had a combination of high BMI (≥30 kg/m2) and high waist circumference (above “Action Level 2”), 32% developed metabolic syndrome, compared with 10% of subjects with both low BMI and low waist circumference. Discussion: These findings support the National Institutes of Health recommendations for reducing the risk of metabolic syndrome. Adjustment for baseline fasting insulin levels had only a small effect on the ability of anthropometric indices to predict the metabolic syndrome.  相似文献   

12.
Hemphill  Delbert D.  Baker  L. R.  Sell  H. M. 《Planta》1972,103(3):241-248
Summary Thin-layer chromatography, gas-liquid chromatography, and mass spectrometry were used to identify gibberellins isolated from mature seeds of both Cucumis sativus (cucumber) and Cucumis melo (muskmelon). The gibberellins were extracted and purified by organic solvent fractionation, paper and thin-layer chromatography, and crystallization. Seeds of C. sativus were found to contain gibberellins A1, A3, A4, and A7 with A1 the predominant species. Seeds of C. melo contained gibberellins A1 and A3 and a trace of A5. Direct probe mass spectrometry of the gibberellins proved successful for identification purposes. Distinctive molecular ions and fragmentation patterns were obtained for each gibberellin.Journal Article No. 5664 from the Michigan Agricultural Experiment Station. This work was supported in part by a grant from the Herman Frasch Foundation.Portions were taken from a thesis submitted in partial fulfillment of the requirements for the Ph.D. degree, Michigan State University, 1971  相似文献   

13.
Prostate cancer represents a significant worldwide public health burden. Epidemiological and genetic epidemiological studies have consistently provided data supporting the existence of inherited prostate cancer susceptibility genes. Segregation analyses of prostate cancer suggest that a multigene model may best explain familial clustering of this disease. Therefore, modeling gene–gene interactions in linkage analysis may improve the power to detect chromosomal regions harboring these disease susceptibility genes. In this study, we systematically screened for prostate cancer linkage by modeling two-locus gene–gene interactions for all possible pairs of loci across the genome in 426 prostate cancer families from Johns Hopkins Hospital, University of Michigan, University of Umeå, and University of Tampere. We found suggestive evidence for an epistatic interaction for six sets of loci (target chromosome-wide/reference marker-specific P≤0.0001). Evidence for these interactions was found in two independent subsets from within the 426 families. While the validity of these results requires confirmation from independent studies and the identification of the specific genes underlying this linkage evidence, our approach of systematically assessing gene–gene interactions across the entire genome represents a promising alternative approach for gene identification for prostate cancer.  相似文献   

14.
Our objective is to test an optimality model of human fertility that specifies the behavioral requirements for fitness maximization in order (a) to determine whether current behavior does maximize fitness and, if not, (b) to use the specific nature of the behavioral deviations from fitness maximization towards the development of models of evolved proximate mechanisms that may have maximized fitness in the past but lead to deviations under present conditions. To test the model we use data from a representative sample of 7,107 men living in Albuquerque, New Mexico, between 1990 and 1993. The model we test proposes that low fertility in modern settings maximizes number of grandchildren as a result of a trade-off between parental fertility and next generation fertility. Results do not show the optimization, although the data do reveal a trade-off between parental fertility and offspring education and income. We propose that two characteristics of modern economies have led to a period of sustained fertility reduction and to a corresponding lack of association between income and fertility. The first is the direct link between costs of investment and wage rates due to the forces of supply and demand for labor in competitive economies. The second is the increasing emphasis on cumulative knowledge, skills, and technologies in the production of resources. Together they produce historically novel conditions. These two features of modern economies may interact with evolved psychological and physiological mechanisms governing fertility and parental investment to produce behavior that maximizes the economic productivity of lineages at the expense of fitness. If cognitive processes evolved to track diminishing returns to parental investment and if physiological processes evolved to regulate fertility in response to nutritional state and patterns of breast feeding, we might expect non-adaptive responses when returns from parental investment do not diminish until extremely high levels are reached. With high economic payoffs from parental investment, people have begun to exercise cognitive regulation of fertility through contraception and family planning practices. Those cognitive processes maynot have evolved to handle fitness trade-offs between fertility and parental investment. A preliminary presentation of this data was published in R. I. M. Dunbar, ed.,Human Reproduction Decisions: Biological and Social Perspectives. New York: St. Martin’s Press, 1995. Support for the research project, “Male Fertility and Parenting in New Mexico,” began with two seed grants from the University of New Mexico’s Biomedical Research Grants Program, 1988 and 1989, and one from the University of New Mexico Research Allocations Committee, 1988. Further seed money as well as interim funding came from the William T. Grant Foundation (#89130589 and #91130501). The major support for the project came from the National Science Foundation from 1990 to 1993 (#BNS-9011723 and #DBS-911552). Both National Science Foundation grants included Research Experience for Undergraduates supplements. Hillard S. Kaplan is an Associate Professor of Anthropology at the University of New Mexico. His earlier research and publications focused on food sharing, time allocation, parental investment, and reproductive strategies among Ache hunter-gatherers in Paraguay, Machiguenga and Piro forager-horticulturalists in Peru, and villagers of several ethnicities in Botswana. New research and theory concern fertility, parental investment, and mating strategies in developed and developing nations. This research formulates a new theory of reproductive decision-making and the demographic transition, integrating human capital and parental investment theory in a synthesis of economic and evolutionary approaches. Jane B. Lancaster is a Professor of Anthropology at the University of New Mexico. Her research and publications are on human reproductive biology and behavior, especially human parental investment; women’s reproductive biology of pregnancy, lactation, and child-spacing; and male fertility and investment in children. Current research with Hillard S. Kaplan is on male life history strategies among a large sample of men in New Mexico. She has coedited three books on human parental investment:School-Age Pregnancy and Parenthood (with B. Hamburg),Parenting across the Life Span (with J. Altmann, A. Rossi, and L. Sherrod), andOffspring Abuse and Neglect (with R. Gelles). She is scientific editor of a quarterly journal,Human Nature: An Interdisciplinary, Biosocial Perspective published by Aldine de Gruyter. She is also a council member of the newly formed Human Behavior and Evolution Society. John A. Bock is Andrew W. Mellon Post-Doctoral Fellow in Epidemiology and Population Health at the National Centre for Epidemiology and Population Health, The Australian National University. His research focuses on the allocation of parental investment and the determinants of children’s activities, integrating aspects of economic and evolutionary theory. He has ongoing field research with Bantu and Bushmen agro-pastoralists and forager-horticulturalists in the Okavango Delta, Botswana. He is also collaborating with Lancaster and Kaplan on the determinants of progeny distribution and homosexuality among New Mexican men. Sara E. Johnson is a Ph.D. candidate at the University of New Mexico. Her major research trajectory focuses on trade-offs in life history characters. Her research experience includes participation in a study of variation in growth and development among children in a multi-ethnic community in the Okavango Delta, Botswana, in addition to her dissertation work on individual variation in growth and mortality among juvenile baboons. She is collaborating with Lancaster and Kaplan on the association between survival and fertility among Albuquerque men.  相似文献   

15.

Objective:

To examine the relative association of abdominal visceral adipose tissue (VAT) with cardiometabolic risk factors between African and European Americans.

Design and Methods:

We conducted a cross‐sectional study of 2035 African Americans from Jackson Heart Study (JHS) and 3170 European Americans from Framingham Heart Study (FHS) who underwent computed tomography assessment of VAT and subcutaneous adipose tissue (SAT). The FHS participants were weighted to match the age distribution of the JHS participants and the metabolic risk factors were examined by study groups in relation to VAT.

Results:

JHS participants had higher rates of obesity, hypertension, diabetes and metabolic syndrome than FHS participants (all p = 0.001). The associations were weaker in JHS women for VAT with blood pressure, triglycerides, HDL‐C, and total cholesterol (pinteraction = 0.03 to 0.001) than FHS women. In contrast, JHS men had stronger associations for VAT with high triglycerides, low HDL, and metabolic syndrome (all pinteraction = 0.001) compared to FHS men. Similar associations and gender patterns existed for SAT with most metabolic risk factors.

Conclusions:

The relative association between VAT and cardiometabolic risk factors is weaker in JHS women compared to FHS women, whereas stronger association with triglycerides and HDL were observed in JHS men.  相似文献   

16.

Objective:

Circulating cortisol and psychosocial stress may contribute to the pathogenesis of obesity and metabolic syndrome (MS). To evaluate these relationships, a cross‐sectional study of 369 overweight and obese subjects and 60 healthy volunteers was performed and reviewed the previous literature.

Design and Methods:

Overweight and obese subjects had at least two other features of Cushing's syndrome. They underwent measurements representing cortisol dynamics (24 h urine cortisol excretion (UFC), bedtime salivary cortisol, 1 mg dexamethasone suppression test) and metabolic parameters (BMI, blood pressure (BP); fasting serum triglycerides, HDL, insulin, and glucose). Subjects also completed the Perceived Stress Scale (PSS). UFC, salivary cortisol, and weight from 60 healthy volunteers were analyzed.

Results:

No subject had Cushing's syndrome. UFC and dexamethasone responses were not associated with BMI or weight. However, salivary cortisol showed a trend to increase as BMI increased (P < 0.0001), and correlated with waist circumference (WC) in men (rs = 0.28, P = 0.02) and systolic BP in women (rs = 0.24, P = 0.0008). Post‐dexamethasone cortisol levels were weak to moderately correlated with fasting insulin (rs = ?0.31, P = 0.01) and HOMA‐IR (rs = ?0.31, P = 0.01) in men and systolic (rs = 0.18, P = 0.02) and diastolic BP (rs = 0.20, P = 0.009) in women. PSS results were higher in obese subjects than controls, but were not associated with cortisol or metabolic parameters. As expected, WC correlated with fasting insulin, HOMA‐IR, and systolic BP (adjusted for BMI and gender; P < 0.01). Literature showed inconsistent relationships between cortisol and metabolic parameters.

Conclusion:

Taken together, these data do not support a strong relationship between systemic cortisol or stress and obesity or MS.
  相似文献   

17.
Objective: NIH Clinical Guidelines (1998) recommend the measurement of waist circumference (WC, centimeters) within body mass index (BMI, kilograms per square meter) categories as a screening tool for increased health risk. Research Methods and Procedures: The Canada Heart Health Surveys (1986 through 1992) were used to describe the prevalence of the metabolic syndrome in Canada and to test the use of the NIH guidelines for predicting metabolic risk factors. The sample included 7981 participants ages 20 to 74 years who had complete data for WC, BMI, high‐density lipoprotein‐cholesterol, triglycerides, diabetic status, and systolic and diastolic blood pressures. National Cholesterol Education Program Adult Treatment Panel III risk categories were used to identify the metabolic syndrome and associated risk factors. Logistic regression was used to test the hypothesis that WC improves the prediction of the metabolic syndrome, within overweight (25 to 29.9 kg/m2) and obese I (30 to 34.9 kg/m2) BMI categories. Results: The prevalence of the metabolic syndrome was 17.0% in men and 13.2% in women. The odds ratios (OR) for the prediction of the metabolic syndrome were elevated in overweight [OR, 1.85; 95% confidence interval (95%CI), 1.02 to 3.35] and obese (OR, 2.35; 95%CI, 1.25 to 4.42) women with a high WC compared with overweight and obese women with a low WC, respectively. On the other hand, WC was not predictive of the metabolic syndrome or component risk factors in men, within BMI categories. Discussion: In women already at increased health risk because of an elevated BMI, the additional measurement of WC may help identify cardiovascular risk.  相似文献   

18.
The eastern massasauga rattlesnake (Sistrurus catenatus catenatus) has experienced population declines throughout its range and is now a candidate for federal protection. However, little is known about massasauga habitat selection in Michigan, particularly in actively managed landscapes. Our objectives were to: 1) quantify whether massasaugas in southwestern Michigan select certain vegetation types disproportionately to their availability and 2) quantify whether the vegetation structure associated with snake locations differed between managed (e.g., burning, woody species removal) and unmanaged stands. We implanted radio transmitters in 51 snakes from 2004 to 2005 and 2008 to 2009. We quantified second-order resource selection using compositional analysis, and modeled the effect of habitat management efforts on vegetation using 4 structural variables. All snakes selected cover types disproportionately to their availability (P = 0.001); a ranking matrix ordered the vegetation types, from most to least used, as: early-mid successional deciduous wetland > early-mid successional deciduous upland > developed > late successional mixed lowland forest > late successional deciduous upland forest. We found that snakes in managed areas were associated with greater amounts of dead herbaceous cover (P = 0.005) and less woody stem density (P < 0.001) and tree dominance (P < 0.001) than were snakes in unmanaged areas; however, live herbaceous cover was comparable. Our results can be used by regional managers to provide early and mid successional habitat with structure similar to that selected by snakes in Michigan. © 2011 The Wildlife Society.  相似文献   

19.
Review of On the Move: How and Why Animals Travel in Groups edited by Sue Boinski and Paul A. Garber. Chicago, University of Chicago Press, 2000, xii + 811 pp, 63 fig., 53 tab., $35.  相似文献   

20.
Pollen records for American beech (Fagus grandifolia) and eastern hemlock (Tsuga canadensis) compiled from 50 sites in Michigan and Wisconsin, USA, show that both species entered the Upper Great Lakes region about 7000 yr B.P., reaching their western and southwestern boundaries between 2000 and 1000 yr B.P. Fagus advanced northward into lower Michigan as a continuous front, except where Lake Michigan posed a geographic barrier. Colonies were established on the far side of the lake after a 1000 year lag, implying that longdistance dispersal across a 100-km wide barrier can occur. The Fagus range may not have been in equilibrium with climate for one or two thousand years before this time, when seeds were dispersed across the lake to Wisconsin. Tsuga seeds may have been dispersed 150 km or more from Ontario to reach Upper Michigan. Scattered colonies were established 6000–7000 yr B.P. on either side of Lake Michigan, which did not pose a significant barrier to this wind-dispersed species, Tsuga spread rapidly over a large region prior to 5000 yr B.P. Subsequent expansion to the west occurred more slowly, and may reflect gradual climatic changes in northern Wisconsin during the second half of the Holocene. Tsuga's range may have been limited by dispersal, rather than climate, for an unknown length of time prior to 5000 yr B.P. During this period Tsuga was expanding its range rapidly. The study shows, however, that it is difficult to devise rigorous tests to distinguish between dispersal limitations and climate as factors limiting range limits in the past.This work has been supported by the U.S. National Science Foundation.This work has been supported by the U.S. National Science Foundation.  相似文献   

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