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1.
Novel and recurrent mutations in the tyrosinase gene and the P gene in the German albino population 总被引:5,自引:0,他引:5
Albinism is a heterogeneous group of genetic disorders resulting from deficiencies in pigmentation. Clinically, it is divided into ocular (OA) and oculocutaneous albinism (OCA). OCA involves lack of pigment in the skin, hair, and eyes and results from mutations in the tyrosinase gene or in the P gene. OA mainly affects pigmentation in the visual system and may be a mild form of OCA or may be caused by other genetic defects. Clinical diagnosis of albinism type is difficult, because of the observed range of phenotypic variation. Thus, genetic analysis may be helpful with respect to a more accurate diagnosis. Here, we report the mutational profile, determined by genetic analysis of the tyrosinase and P genes, of a large German albino population. We have revealed a total of 42 distinct mutations, 19 of which are novel. Of the 74 unrelated patients screened, 32 (43%) had mutations in the tyrosinase gene, 16 (22%) had P gene mutations, and 26 (35%) patients had no detectable genetic abnormalities. This defines a population of albino patients who are tyrosinase-gene- and P-gene-negative and who thus may represent a good study group for searching for additional genes associated with albinism. 相似文献
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Comstock BA Solomon-Hill G Flanagan SD Earp JE Luk HY Dobbins KA Dunn-Lewis C Fragala MS Ho JY Hatfield DL Vingren JL Denegar CR Volek JS Kupchak BR Maresh CM Kraemer WJ 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(8):2293-2297
The purpose of this study was to verify the concurrent validity of a bar-mounted Myotest? instrument in measuring the force and power production in the squat and bench press exercises when compared to the gold standard of a computerized linear transducer and force platform system. Fifty-four men (bench press: 39-171 kg; squat: 75-221 kg) and 43 women (bench press: 18-80 kg; squat: 30-115 kg) (age range 18-30 years) performed a 1 repetition maximum (1RM) strength test in bench press and squat exercises. Power testing consisted of the jump squat and the bench throw at 30% of each subject's 1RM. During each measurement, both the Myotest? instrument and the Celesco linear transducer of the directly interfaced BMS system (Ballistic Measurement System [BMS] Innervations Inc, Fitness Technology force plate, Skye, South Australia, Australia) were mounted to the weight bar. A strong, positive correlation (r) between the Myotest and BMS systems and a high correlation of determination (R2) was demonstrated for bench throw force (r = 0.95, p < 0.05) (R2 = 0.92); bench throw power (r = 0.96, p < 0.05) (R2 = 0.93); squat jump force (r = 0.98, p < 0.05) (R2 = 0.97); and squat jump power (r = 0.91, p < 0.05) (R2 = 0.82). In conclusion, when fixed on the bar in the vertical axis, the Myotest is a valid field instrument for measuring force and power in commonly used exercise movements. 相似文献
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Martins DB Mazzanti CM França RT Pagnoncelli M Costa MM de Souza EM Gonçalves J Spanevello R Schmatz R da Costa P Mazzanti A Beckmann DV Cecim Mda S Schetinger MR Lopes ST 《Life sciences》2012,90(9-10):351-359
AimsTo investigate the 17-β estradiol in the acetylcholinesterase activity and lipid peroxidation in the brain and blood of ovariectomized rats of different ages.Main methodsAnimals were randomly assigned into three experimental groups of each age (n = 6). Control groups consisted of adult (sham-A) and middle-aged (sham-MA) female rats, ovariectomized adult (OVX-A) and middle-aged (OVX-MA) rats without estrogen therapy reposition, and ovariectomized adult (OVX + E2-A) and middle-aged (OVX + E2-MA) rats treated with 17-β estradiol for 30 days. After this period, AChE activity and lipid peroxidation were measured in the brain and blood.Key findingsThe AChE activity increased (p < 0.05) in striatum (ST) in OVX-A, OVX + E2-A and OVX-MA, and hippocampus (HP) in OVX-MA. The enzyme activity decreased (p < 0.05) in ST of OVX + E2-MA, and cerebral cortex (CC) in OVX + E2-A, OVX-MA and OVX + E2-MA. Blood AChE activity increased (p < 0.05) in OVX + E2-A and decreased (p < 0.05) in OVX-MA. Lymphocyte AChE activity increased (p < 0.05) in OVX-A and OVX + E2-A and decreased (p < 0.05) in OVX-MA. Lipid peroxidation increased (p < 0.05) in ST of OVX-A, CC of OVX-A and OVX-MA, HP of OVX-A, and cerebellum (CE) of OVX-A, OVX-MA, and OVX + E2-MA. Lipid peroxidation decreased (p < 0.05) in ST, CC and CE of OVX + E2-A, and ST and HP of OVX + E2-MA. Similar values of lipid peroxidation to control groups were found in ST and HP of OVX-MA, HP of OVX + E2-A and CC of OVX + E2-MA.Significance17-β estradiol is able to modulate the AChE activity and non-neuronal cholinergic response as well as to reduce lipid peroxidation. Its response is dependent on the age and brain structure analyzed. 相似文献
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Zielke H. Ronald Huang Yinyin Baab Peter J. Collins Roger M. Zielke Carol L. Tildon J. Tyson 《Neurochemical research》1997,22(9):1159-1164
Leucine and -ketoisocaproate (-KIC) were perfused at increasing concentrations into rat brain hippocampus by microdialysis to mimic the conditions of maple syrup urine disease. The effects of elevated leucine or -KIC on the oxidation of L-[U-14C]glutamate and L-[U-14C]glutamine in the brain were determined in the non-anesthetized rat. 14CO2 generated by the metabolic oxidation of [l4C]glutamate and [14C]glutamine in brain was measured following its diffusion into the eluant during the microdialysis. Leucine and -KIC exhibited differential effects on 14CO2 generation from radioactive glutamate or glutamine. Infusion of 0.5 mM -KIC increased [l4C]glutamate oxidation approximately 2-fold; higher concentrations of -KIC did not further stimulate [14C]glutamate oxidation. The enhanced oxidation of [14C]glutamate may be attributed to the function of -KIC as a nitrogen acceptor from [14C]glutamate yielding [14C]-ketoglutarate, an intermediate of the tricarboxylic acid cycle. [14C-]glutamine oxidation was not stimulated as much as [14C-]glutamate oxidation and only increased at 10 mM -KIC reflecting the extra metabolic step required for its oxidative metabolism. In contrast, leucine had no effect on the oxidation of either [14C]glutamate or [14C]glutamine. In maple syrup urine disease elevated -KIC may play a significant role in altered energy metabolism in brain while leucine may contribute to clinical manifestations of this disease in other ways. 相似文献
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Masahiko Idei Keigo Osada Shinya Sato Takeshi Nakayama Tamotsu Nagumo David G. Mann 《Protoplasma》2013,250(4):833-850
The most complete account to date of the ultrastructure of flagellate cells in diatoms is given for the sperm of Thalassiosira lacustris and Melosira moniliformis var. octogona, based on serial sections. The sperm are uniflagellate, with no trace of a second basal body, and possess a 9?+?0 axoneme. The significance of the 9?+?0 configuration is discussed: lack of the central pair microtubules and radial spokes does not compromise the mastigoneme-bearing flagellum’s capacity to perform planar beats and thrust reversal and may perhaps be related to sensory/secretory function of the sperm flagellum during plasmogamy. The basal bodies of diatoms are confirmed to contain doublets rather than triplets, which may correlate with the absence of some centriolar proteins found in most cells producing active flagella. Whereas Melosira possesses a normal cartwheel structure in the long basal body, no such structure is present in Thalassiosira, which instead possesses ‘intercalary fibres’ linking the basal body doublets. No transitional helices or transitional plates are present in either species studied. Cones of microtubules are associated with the basal body and partially enclose the nucleus in M. moniliformis and T. lacustris. They do not appear to be true microtubular roots and may arise through transformation of the meiosis II spindle. A close association between cone microtubules and tubules containing mastigonemes may indicate a function in intracellular mastigoneme transport. No correlation can yet be detected between methods of spermatogenesis and phylogeny in diatoms, contrary to previous suggestions. 相似文献
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Chris Hann 《The journal of the Royal Anthropological Institute》2022,28(1):5-29
When T.H. Huxley lectured on evolution and ethics in 1893, his critique of the amoral laws of the ‘cosmic process’ left his audience puzzled. While Huxley paid little attention to political and economic institutions, this article draws attention to the historical materialism of that era and its twentieth-century legacies. Empirically, it analyses the rise and fall of a Hungarian state farm with reference to the comparative literature on twentieth-century socialist societies. Theoretically, socialism is considered as the combination of a materialist philosophy of history with an axial ethical impulse. In the aftermath of the collapse of the Eurasian socialist order in the 1990s, we can see why Huxley was right to deplore the ‘fanatical individualism’ of his age. His humanism resembles that of the early Karl Marx and he stands closer to Émile Durkheim than to contemporary currents in the anthropology of ethics. 相似文献
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Involvement of binding lipoproteins in the absorption and transport of α-tocopherol in the rat 总被引:1,自引:1,他引:0
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1. Specific lipoproteins binding alpha-tocopherol but not its known metabolites have been isolated and identified from cytosol of rat intestinal mucosa and from serum. 2. A timestudy of the appearance of the orally administered alpha-[(3)H]tocopherol with these lipoproteins indicates that very-low-density lipoprotein of serum acts as a carrier of the vitamin. 3. The involvement of the mucosal lipoprotein in the absorption of the vitamin from the intestine has been inferred from observations on the amounts of alpha-tocopherol in serum of orotic acid-fed rats where release of lipoproteins from the liver to serum is completely inhibited. A considerable decrease in the association of alpha-tocopherol with serum very-low-density lipoprotein under this condition is interpreted to mean that serum lipoproteins are limiting factors for the transport of the vitamin across the intestine and that this is possibly effected by exchange of alpha-tocopherol between serum very-low-density lipoprotein and mucosal lipoprotein. 相似文献
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Littorals in the in the Exuma Cays, Bahamas and the Bath Plantation, Barbados are comparative in many ways. These edges of
the sea have provided critical services to local people during the time of slavery and since. More than food and medicine,
the littoral is the nightly sea bath, where children are instructed, and the last ecosystem effectively used by the elderly.
Independence and self-respect derive from use and protection of these littoral by individuals and communities. Local patterns
of conservation and use are argued to be essential in the ecological structure and functions of the littoral. Development
projects and marine protected areas alike are seen as potentially breaking local ties with the littoral causing trophic skew
and damaging local society. If development occurs, mitigation solutions potentially derive from legally recognizing local
people as partners in the co-management of their traditional littoral.
相似文献
Richard W. Stoffle (Corresponding author)Email: |
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Besides bringing problems, aging can let the mind's eye see more clearly than before, and it can let us express ourselves better. As age, experience and common sense examine today's skeletal medicine and surgery two questions keep popping up: A) How did we fail?; B) How to make it better? The Utah paradigm of skeletal physiology and the seminal ISMNI offer some answers, but exploiting them faces problems. Problem #1: By 1960 all clinicians and physiologists 'knew' (as the ancients 'knew' this world is flat) that effector cells controlled solely by nonmechanical agents explain all skeletal physiology and disorders ('effector cells' include osteoblasts, osteoclasts, chondroblasts and fibro-blasts). Or, nonmechanical agents -->cell level -->organ and intact subject. Adding later-discovered information to that 1960 view led to the Utah paradigm, which reveals the formerly hidden tissue-level 'dimension' of skeletal physiology. It builds on this idea: (mechanical + nonmechanical agents) -->(tissue level + cell level) --> organ and intact subject. The paradigm assigns great influence of neuromuscular physiology and physical activities on skeletal architecture, strength and mechanical competence. It also exposes flaws in many older views so controversies arise. Problem #2: The Utah paradigm and Wegner's concept of plate tectonics in geology seem alike in that each is valid but came before its time, so others fought it. They differ in this: The fight about Wegner's idea is over, but for the Utah paradigm and the ISMNI it just began. Hence more controversies. Nevertheless: A growing minority realizes that paradigm provides a far better base to build on than its antecedents, and since it keeps evolving as more evidence comes in it could endure for some decades. Yet very few realize this: It and the ISMNI have important implications for fields besides biomechanics and orthopaedics. Examples include anatomy, cardiovascular disease, dentistry, endocrinology, family medicine, gastroenterology, general surgery, genetics, gerontology, gynecology, maxillofacial surgery, neurology, neurosurgery, nutrition, ophthalmology, pathology, pediatrics, physical medicine and rehabilitation, plastic surgery, radiology, rheumatology, space and sports medicine, and urology. Quite a list! For the italicized questions above this article offers answers, of which its conclusion distills an essence. 相似文献
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Nada Horvatin?i? Ines Krajcar Broni?Bogomil Obeli? 《Palaeogeography, Palaeoclimatology, Palaeoecology》2003,193(1):139-157
We studied Holocene speleothems and tufa samples collected in numerous caves and rivers in the Dinaric Karst of Croatia, Slovenia, Bosnia and Herzegovina, as well as Serbia and Montenegro. Differences in the formation process of tufa and speleothems are discussed in the context of their isotopic composition (14C, 13C and 18O), as well as the chemistry of surface water (rivers, lakes) and drip water (in caves). The physical and chemical parameters monitored in the surface water (tufa precipitation) and drip water (speleothem precipitation) show that more stable conditions accompany speleothem rather than tufa formation. This is particularly obvious in the water temperature variations (2-22°C in surface water and 7-12°C in drip water) and in saturation index variation (3-11 in surface water and 1-6 in drip water). The range of 14C ages recorded by Holocene speleothems (∼12?000 yr) is wider by several thousands years than that of Holocene tufa samples (∼6000 yr). δ13C values for tufa samples range from −12‰ to −6‰ and for speleothem samples from −12‰ to +3‰ reflecting higher soil carbon and/or vegetation impact on the process of tufa than on speleothem formation. The differences in δ18O values of tufa and speleothem samples from different areas reflect different temperature conditions and differing isotopic composition in the water. The study shows that speleothems from the Dinaric Karst can be used as global palaeoclimatic records, whereas tufa records changes in the local palaeoenvironment. 相似文献
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J Maurin C Bouillé J D Baylé 《Archives internationales de physiologie et de biochimie》1978,86(1):53-65
Extensive multiple electrolytic lesions were placed into the nucleus raphes of the brain stem in the pigeon. Diurnal pituitary-adrenocortical rhythmicity appeared not to be altered and basal plasma corticosterone level remained quite normal in raphe lesioned birds. Electrical stimulations through permanently implanted electrode were delivered in various central nervous structures in unanaesthetized, freely moving pigeons. Stimulations of nucleus raphes and of various parts of formatio reticularis led to a significant rise in plasma corticosterone within 16 to 19 min after the beginning of the stimulating session. Then, plasma B came again to initial level within 15 minutes. Stimulations of the corticotropic area of the hypothalamus (n. posterior medialis hypothalami) and of archistriatum dorsalis induced an early plasma corticosterone increase occurring immediately after the stimulating burst (10 min). Stimulating the n. septum medialis also had an immediate, but reverse (decrease) effect on plasma corticosterone level. Stress-induced pituitary-adrenal cortical activation exhibited a temporal pattern quite similar to that observed after brain stem (n. raphes or formatio reticularis) stimulation. It is suggested that these various limbic and brain stem areas might be involved in some "limbic system-midbrain circuit" with two components : The forebrain component might be involved in the regulation and diurnal modulation of basal hypothalamic-pituitary-adrenocortical function, the brain-stem component interferring with stress-induced responses. 相似文献
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Human and non-human animals tend to avoid risky prospects. If such patterns of economic choice are adaptive, risk preferences should reflect the typical decision-making environments faced by organisms. However, this approach has not been widely used to examine the risk sensitivity in closely related species with different ecologies. Here, we experimentally examined risk-sensitive behaviour in chimpanzees (Pan troglodytes) and bonobos (Pan paniscus), closely related species whose distinct ecologies are thought to be the major selective force shaping their unique behavioural repertoires. Because chimpanzees exploit riskier food sources in the wild, we predicted that they would exhibit greater tolerance for risk in choices about food. Results confirmed this prediction: chimpanzees significantly preferred the risky option, whereas bonobos preferred the fixed option. These results provide a relatively rare example of risk-prone behaviour in the context of gains and show how ecological pressures can sculpt economic decision making. 相似文献
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The study aimed to identify the changes of anatomic and microscopic structure and the expression and localization of hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) in the myocardium and coronary artery of the yak heart adapted to chronic hypoxia with aging. Thirty-two yaks (1 day, 6 months, 1 year, 2 years, and 5 year old) were included, and immunoelectronmicroscopy, immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA) were used. Right ventricular hypertrophy was not present in yaks with aging. There was no intima thickening phenomenon in the coronary artery. The ultrastructure of myofibrils, mitochondria, and collagen fibers and the diameter and quantity of collagen changed significantly with aging. The enzymatic activity of complexes I, II, and V increased with age. Immunogold labeling showed the localization of HIF-1α protein in the cytoplasm and nuclei of endothelial cells and cytoplasm of cardiac muscle cells, and VEGF protein in the nuclei and perinuclei areas of smooth muscle cells of coronary artery, and in the cytoplasm and nuclei of endothelial cells. ELISA results showed that HIF-1α secretion significantly increased in the myocardium and coronary artery from an age of 1 day to 2 years of yaks and decreased in old yaks. However, VEGF protein always increased with aging. The findings of this study suggest that 6 months is a key age of yak before which there are some adaptive changes to deal with low-oxygen environment, and there is a maturation of the yak heart from the age of 6 months to 2 years. 相似文献
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Dr. Neville N. Osborne 《Cell and tissue research》1984,237(3):605-608
Summary The presence of dopamine--hydroxylase (DBH) and phenylethanol-amine-N-methyltransferase (PNMT) immunoreactivity in specific neurones of the snail Helix aspersa has been demonstrated. In addition, high performance liquid chromatography and electrochemical detection have revealed the presence of noradrenaline and adrenaline in the snail central nervous system, although the major catecholamine is dopamine. These results suggest that adrenaline, and perhaps noradrenaline, have transmitter or modulatory functions in the snail nervous system. 相似文献
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Jeschke U Richter DU Hammer A Briese V Friese K Karsten U 《Histochemistry and cell biology》2002,117(3):219-226
The Thomsen-Friedenreich (TF) antigen (or, more precisely, epitope Galbeta1-3GalNAcalpha-O-) has been known for a long time as a carcinoma-associated antigen. In normal tissues the occurrence of TF antigen is restricted to a few immunologically privileged areas. Here we report on the identification of the TF epitope and its putative carrier protein mucin 1 (MUC1) in human placental tissue, on isolated trophoblast cells in vitro and on trophoblast tumour cell lines BeWo and Jeg3. Cryosections of placental and decidual tissues of the first, second and third trimester were double stained with monoclonal antibodies directed against the TF epitope (IgM) and against MUC1 (IgG). In the first trimester of pregnancy we found strong expression of TF antigen and MUC1 at the apical side of the syncytiotrophoblast directed towards the maternal blood. This expression was consistent in the second trimester of pregnancy, and to a lesser degree in the third trimester. In addition, we found positive staining for TF antigen and MUC1 on extravillous trophoblast cells in the decidua during the first and second trimester of pregnancy. Trophoblast tumour cells of the cell line BeWo, which form a syncytium in vitro, were also positive for TF antigen and MUC1, whereas Jeg3 cells, which are unable to form a syncytium, expressed only MUC1. Freshly isolated trophoblast cells from first trimester placentas showed strong staining for MUC1; however, only a few of these cells (less than 1%) were positive for TF antigen, and might consist of digested fragments of the syncytium. In summary, TF antigen and MUC1 are expressed by the syncytiotrophoblast at the feto-maternal interface and by extravillous trophoblast cells invading the decidua, whereas villous cytotrophoblast cells in situ as well as freshly isolated trophoblast cells from first trimester placentas only express MUC1 but not TF antigen. 相似文献
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