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1.
Copper (Cu) is an essential microelement found in all living organisms with the unique ability to adopt two different redox states—in the oxidized (Cu2+) and reduced (Cu+). It is required for survival and serves as an important catalytic cofactor in redox chemistry for proteins that carry out fundamental biological functions, important in growth and development. The deficit of copper can result in impaired energy production, abnormal glucose and cholesterol metabolism, increased oxidative damage, increased tissue iron (Fe) accrual, altered structure and function of circulating blood and immune cells, abnormal neuropeptides synthesis and processing, aberrant cardiac electrophysiology, impaired myocardial contractility, and persistent effects on the neurobehavioral and the immune system. Increased copper level has been found in several disorders like e.g.: Wilson’s disease or Menke’s disease. New findings with the great potential for impact in medicine include the use of copper-lowering therapy for antiangiogenesis, antifibrotic and anti-inflammatory purposes. The role of copper in formation of amyloid plaques in Alzheimer’s disease, and successful treatment of this disorder in rodent model by copper chelating are also of interest. In this work we will try to describe essential aspects of copper in chosen diseases. We will represent the evidence available on adverse effect derived from copper deficiency and copper excess. We will try to review also the copper biomarkers (chosen enzymes) that help reflect the level of copper in the body.  相似文献   

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The major histocompatibility complex (MHC) is an immunologically important group of genes that appears to be under natural as well as sexual selection. Several hypotheses suggest that certain MHC-allele combinations (usually heterozygous ones) are superior under selective pressure by pathogens. This could influence mate choice in a way that preferences function to create MHC-heterozygous offspring, or that they function to create specific allele combinations that are beneficial under the current environmental conditions through their complementary or epistatic effects. To test these hypotheses, we asked 121 men and women to score the odours of six T-shirts, worn by two women and four men. Their scorings of pleasantness correlated negatively with the degree of MHC similarity between smeller and T-shirt-wearer in men and women who were not using the contraceptive pill (but not in Pill-users). Depending on the T-shirt-wearer, the amount of variance in the scorings of odour pleasantness that was explained by the degree of MHC similarity (r2) varied between nearly 0 and 23%. There was no apparent effect of gender in this correlation: the highest r2 was actually reached with one of the male odours sniffed by male smellers. Men and women who were reminded of their own mate/ex-mate when sniffing a T-shirt had significantly fewer MHC-alleles in common with this T-shirt-wearer than expected by chance. This suggests that the MHC or linked genes influence human mate choice. We found no significant effect when we tested for an influence of the MHC on odour preferences after the degree of similarity between T-shirt-wearer and smeller was statistically controlled for. This suggests that in our study populations the MHC influences body odour preferences mainly, if not exclusively, by the degree of similarity or dissimilarity. The observed preferences would increase heterozygosity in the progeny. They do not seem to aim for more specific MHC combinations.  相似文献   

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It has been anticipated that new, much more sensitive, next generation sequencing (NGS) techniques, using massively parallel sequencing, will likely provide radical insights into the genetics of multifactorial diseases. While NGS has been used initially to analyze individual human genomes, and has revealed considerable differences between healthy individuals, we have used NGS to examine genetic variation within individuals, by sequencing tissues “in depth”, i.e., oversequencing many thousands of times. Initial studies have revealed intra-tissue genetic heterogeneity, in the form of multiple variants of a single gene that exist as distinct “majority and “minority” variants. This highly specialized form of somatic mosaicism has been found within both cancer and normal tissues. If such genetic variation within individual tissues is widespread, it will need to be considered as a significant factor in the ontogeny of many multifactorial diseases, including cancer. The discovery of majority and minority gene variants and the resulting somatic cell heterogeneity in both normal and diseased tissues suggests that selection, as opposed to mutation, might be the critical event in disease ontogeny. We, therefore, are proposing a hypothesis to explain multifactorial disease ontogeny in which pre-existing multiple somatic gene variants, which may arise at a very early stage of tissue development, are eventually selected due to changes in tissue microenvironments.  相似文献   

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Victor C. de Munck 《Ethnos》2013,78(3-4):219-231
This article examines the interplay of local, national, and international historical and contemporary processes as manifested in a Sri Lankan Muslim village festival. The author shows that the festival is a product of the historical isolation of the village and its attempt to establish a distinct Muslim social identity. In contemporary Sri Lanka a separate Muslim identity is no longer in doubt and the festival has become a focal event for competing and, potentially, mutually exclusive social identities as exemplified by Sufism, Sri Lankan nationalism, and pan‐Islamic fundamentalism.  相似文献   

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BackgroundVitamin E and its derivatives, namely, the tocopherols, are known antioxidants, and numerous clinical trials have investigated their role in preventing cardiovascular disease; however, evidence to date remains inconclusive. Much of the in vitro research has focused on tocopherol's effects during low-density lipoprotein (LDL) oxidation, with little attention being paid to very LDL (VLDL) and high-density lipoprotein (HDL). Also, it is now becoming apparent that γ-tocopherol may potentially be more beneficial in relation to cardiovascular health.ObjectivesDo α- and γ-tocopherols become incorporated into VLDL, LDL and HDL and influence their oxidation potential in an in vitro and ex vivo situation?DesignFollowing (i) an in vitro investigation, where plasma was preincubated with increasing concentrations of either α- or γ-tocopherol and (ii) an in vivo 4-week placebo-controlled intervention with α- or γ-tocopherol. Tocopherol incorporation into VLDL, LDL and HDL was measured via high-pressure liquid chromatography, followed by an assessment of their oxidation potential by monitoring conjugated diene formation.ResultsIn vitro: Both tocopherols became incorporated into VLDL, LDL and HDL, which protected VLDL and LDL against oxidation. However and surprisingly, the incorporation into HDL demonstrated pro-oxidant properties. Ex vivo: Both tocopherols were incorporated into all three lipoproteins, protecting VLDL and LDL against oxidation; however, they enhanced the oxidation of HDL.ConclusionsThese results suggest that α- and γ-tocopherols display conflicting oxidant activities dependent on the lipoprotein being oxidized. Their pro-oxidant activity toward HDL may go some way to explain why supplementation studies with vitamin E have not been able to display cardioprotective effects.  相似文献   

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Background

“A Body Shape Index” (ABSI) is a recently proposed index that standardizes waist circumference for body mass index (BMI) and height. This study aims to: (a) examine if the ABSI scaling exponents for standardizing waist circumference for BMI and height are valid in middle-aged and older Indonesian population, and (b) compare the association between incident hypertension and ABSI and other anthropometric measures.

Methods and Findings

The Indonesian Family Life Survey Wave 3 measured anthropometric variables and blood pressure of 8255 adults aged between 40 to 85 years in 2000. The relationship between two anthropometric quantities, e.g. weight (w) and height (h), can be expressed as the power law-equivalent , where p = 2 is the scaling exponent in the derivation of the BMI and can be estimated by linear regression analysis. This was extended to the regression analysis of the log-transformed waist circumference, weight and height to establish the scaling exponents in the ABSI. The values for men were similar to those developed by the previous American study, which were 2/3 (BMI) and 1/2 (height). Those for women were somewhat smaller, at 3/5 (BMI) and 1/5 (height). The original (American) ABSI leads to mild negative correlation with BMI (−0.14) and height (−0.12) in the female population. Analysis of the development of hypertension between Waves 3 and 4 (average interval 7.5 years) in relation to ABSI measured at Wave 3 showed stronger association if the locally derived (Indonesian) scaling exponents were used. However, both versions of the ABSI were less associated with incident hypertension than waist circumference and BMI.

Conclusions

The values for the scaling exponents for ABSI are roughly similar between the American population and the middle-aged and older Indonesian population, although larger discrepancy was found in women. The ABSI is less associated with incident hypertension than waist circumference and BMI.  相似文献   

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Cota D  Barrera JG  Seeley RJ 《Neuron》2006,51(6):678-680
Leptin receptors are expressed on mesolimbic dopamine neurons, yet little is known about the functional significance of this anatomical relationship. In this issue of Neuron, Hommel et al. reveal a novel site for leptin's regulation of feeding. In turn, Fulton et al. propose a novel role for leptin in regulating non-feeding-related motivated behaviors.  相似文献   

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We explored the relationships between facial attractiveness and several variables thought to be related to genotypic and phenotypic quality in humans (namely fluctuating asymmetry (FA), body mass index (BMI), health, age). To help resolve some controversy around previous studies, we used consistent measurement and statistical methods and relatively large samples of both female (n=94) and male (n=95) subjects (to be evaluated and measured), and female (n=226) and male (n=153) viewers (to rate attractiveness). We measured the asymmetry of 22 traits from three trait families (eight facial, nine body and five fingerprint traits) and constructed composite asymmetry indices of traits showing significant repeatability. Facial attractiveness was negatively related to an overall asymmetry index in both females and males, with almost identical slopes. Female facial attractiveness was best predicted by BMI and past health problems, whereas male facial attractiveness was best predicted by the socioeconomic status (SES) of their rearing environment. Composite FA indices accounted for a small (<4%) but usually significant percentage of the variation in facial attractiveness in both sexes, when factors related to asymmetry were controlled statistically. We conclude that, although facial attractiveness is negatively related to developmental instability (as measured by asymmetry), attractiveness also signals different aspects of “quality” in the two sexes, independent of FA.  相似文献   

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A new method will be presented which allows the perception of body odors in humans to be studied objectively. The analysis of body odor‐evoked potentials was used to investigate if and how the human brain is able to differentiate self from non‐self body odor for the first time. Six subjects (three females) participated in two experimental sessions. In each session, two body odors (axillary hair) were presented within an olfactory oddball paradigm. One of the odors was collected from the subject and the other from an odor donor of the same sex. In the first session the subjects' attention was distracted to a secondary task (passive paradigm), in the second session the subjects were asked to actively differentiate the odors (active paradigm). For the EEG recordings the odors were presented within a constantly flowing airstream. The results show that the subjects could hardly differentiate the body odors subjectively. However, it could be demonstrated that the central nervous processing of one's own odor was faster than the processing of the chemosensory non‐self signal. Moreover, in the active paradigm, the potentials appeared to be larger when the subjects perceived their own body odor. The conclusion is reached that the measurement of chemosensory event‐related potentials (CSERP) is the method of choice for the investigation of HLA‐associated body odors. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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The effects of shift and time‐on‐shift on alertness and perceived tension, as well as related physiological variables, were investigated in satellite controllers working a rapid forward rotating three‐shift system. In controlled laboratory conditions, subjective tension and HR have been reported to display circadian variation and marked sensitivity to external factors. We examined whether circadian variations were masked for these particular variables in real‐job conditions, unlike for alertness and body temperature, which have been repeatedly shown to display circadian variation in these conditions. This hypothesis was tested in a repeated‐measures design by collecting alertness and tension self‐reports and recording operators' sublingual temperature on three occasions on each shift and HR continuously throughout shifts. Alertness and body temperature varied according to a typical diurnal trend; subjective tension was only enhanced on the initial recording of each shift (compared to the remaining ones), while HR displayed an intermediary trend. Intra‐subject correlations revealed a positive relationship between alertness, oral temperature, and HR, while no such relationship was found for subjective tension. These results support the hypothesis of a close dependence of alertness and temperature, and to a lesser extent for HR, on endogenous mechanisms in this job‐situation. In addition, some situation‐specific factors, such as job‐demand, would affect subjective tension and partially mask the circadian variations in HR.  相似文献   

15.
Abstract

Using data for sixty less‐developed countries, we constructed a causal model in which medical care, nutrition, status of women, and socioeconomic development are examined as determinants of infant mortality. Social and economic development are treated as exogenous variables; medical care, nutrition, and status of women are viewed as variables endogenous to the model. The model is tested by maximum likelihood methods. Results indicate that good nutrition and the presence of informally trained health care personnel, i.e., midwives, are more significantly related to low rates of infant mortality than are the employment status of women and the presence of formally trained health care personnel such as physicians and nurses. The general level of social and economic development conditions these relationships.  相似文献   

16.
The appearance of depigmentation during the course of malignant melanoma has been considered a good prognostic sign. Is it only a side-effect, informative of the immune system's response to the treatment, or does it act as a necessary amplifier of these clinically important anti-tumor responses? The current review will attempt to tackle this question by reviewing the current literature, as well as by posing some novel hypotheses. Understanding the nature of humoral and cellular immune responses directed against normal melanocytes and their malignant counterparts may lead to the design of improved therapeutic strategies relevant to both vitiligo and melanoma.  相似文献   

17.
The nitric oxide (NO) system is involved in the regulation of the cardiovascular system in controlling central and peripheral vascular tone and cardiac functions. It was the aim of this study to investigate in wild‐type C57BL/6 and endothelial nitric oxide synthase (eNOS) knock‐out mice (eNOS‐/‐) the contribution of NO on the circadian rhythms in heart rate (HR), motility (motor activity [MA]), and body temperature (BT) under various environmental conditions. Experiments were performed in 12∶12 h of a light:dark cycle (LD), under free‐run in total darkness (DD), and after a phase delay shift of the LD cycle by ?6 h (i.e., under simulation of a westward time zone transition). All parameters were monitored by radiotelemetry in freely moving mice. In LD, no significant differences in the rhythms of HR and MA were observed between the two strains of mice. BT, however, was significantly lower during the light phase in eNOS‐/‐ mice, resulting in a significantly greater amplitude. The period of the free‐running rhythm in DD was slightly shorter for all variables, though not significant. In general, rhythmicity was greater in eNOS‐/‐ than in C57 mice both in LD and DD. After a delay shift of the LD cycle, HR and BT were resynchronized to the new LD schedule within 5–6 days, and resynchronization of MA occurred within 2–3 days. The results in telemetrically instrumented mice show that complete knock‐out of the endothelial NO system—though expressed in the suprachiasmatic nuclei and in peripheral tissues—did not affect the circadian organization of heart rate and motility. The circadian regulation of the body temperature was slightly affected in eNOS‐/‐ mice.  相似文献   

18.
Of all the former Soviet republics, Kazakhstan has what may well be the most untenable interethnic predicament ‐ an ethnic Russian population that is nearly as large as the ethnic Kazakh population. The Russians, moreover, constitute a majority of the population in the northern part of the country, which borders the Russian republic. Having the unenviable task of nation‐building in an increasingly fragmented multi‐ethnic environment, Nazarbaev has made his strategy clear: build a strong unitary Kazakh state by steadily increasing control over the Russian‐dominated provinces of the north. Kazakh action in the north, and Russian response, will determine whether there is a future for a multinational Kazakhstan.  相似文献   

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Abstract

This paper investigates a late nineteenth‐century fertility transition in a predominantly Mormon population of the western United States. A unique set of longitudinal data composed of 31,500 computerized family genealogies is drawn upon to examine a number of problems identified in reappraisals of fertility transition research (Caldwell, 1981; Freedman, 1979). Four subcohorts, differentiated by religious commitment and exposure to urban influences, are examined over the course of the transition. The study presents traditional analyses of subcohort CEB levels, period MTFR's, and m values (Coale and Trussell, 1974) and focuses on a macrosimulation of the fertility transition within the population (Bongaarts, 1976). Despite wide subcohort variation in cross‐sectional levels of fertility over time, simulation results suggest a similar absolute longitudinal decline in fertility levels, parity at which contraception was initiated, and maximum birth parities for all four subcohorts. The implications of these results for future analyses and the desirability of individual level data are discussed.  相似文献   

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