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1.
Despite uncontested evidence for fossils belonging to the early hominin genus Australopithecus in East Africa from at least 4.2 million years ago (Ma), and from Chad by 3.5 Ma, thus far there has been no convincing evidence of Australopithecus, Paranthropus or early Homo from the western (Albertine) branch of the Rift Valley. Here we report the discovery of an isolated upper molar (#Ish25) from the Western Rift Valley site of Ishango in Central Africa in a derived context, overlying beds dated to between ca. 2.6 to 2.0 Ma. We used µCT imaging to compare its external and internal macro-morphology to upper molars of australopiths, and fossil and recent Homo. We show that the size and shape of the enamel-dentine junction (EDJ) surface discriminate between Plio-Pleistocene and post-Lower Pleistocene hominins, and that the Ishango molar clusters with australopiths and early Homo from East and southern Africa. A reassessment of the archaeological context of the specimen is consistent with the morphological evidence and suggest that early hominins were occupying this region by at least 2 Ma.  相似文献   
2.

The broad spectrum of health benefits attributed to probiotics has contributed to a rapid increase in the value of the probiotic market. Probiotic health benefits can be strain specific. Thus, strain-level identification of probiotic strains is of paramount importance to ensure probiotic efficacy. Both Lactobacillus gasseri BNR17 and Lactobacillus reuteri LRC (NCIMB 30242) strains have clinically proven health benefits; however, no assays were developed to enable strain-level identification of either of these strains. The objective of this study is to develop strain-specific PCR-based methods for Lactobacillus gasseri BNR17 and Lactobacillus reuteri LRC strains, and to validate these assays according to the guidelines for validating qualitative real-time PCR assays. Using RAST (Rapid Annotation using Subsystem Technology), unique sequence regions were identified in the genome sequences of both strains. Probe-based assays were designed and validated for specificity, sensitivity, efficiency, repeatability, and reproducibility. Both assays were specific to target strain with 100% true positive and 0% false positive rates. Reaction efficiency for both assays was in the range of 90 to 108% with R square values > 0.99. Repeatability and reproducibility were evaluated using five samples at three DNA concentrations each and relative standard deviation was < 4% for repeatability and < 8% for reproducibility. Both of the assays developed and validated in this study for the specific identification of Lactobacillus gasseri BNR17 and Lactobacillus reuteri LRC strains are specific, sensitive, and precise. These assays can be applied to evaluate and ensure compliance in probiotic products.

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3.
Molecular Biology Reports - Breast cancer is one of the most common cancer types among women in which early tumor invasion leads to metastases and death. EpCAM (epithelial cellular adhesion...  相似文献   
4.
The scarcity of Neandertal remains from Southern Europe hampers our understanding of Neandertal variability, and can bias interpretations about Neandertal geographic variation. To address this issue, it is often important to reassess human remains that, while discovered decades ago, remain relatively unknown to the scientific community. In this contribution, we provide a complete state‐of‐the‐art comparative morphometric analysis of Leuca I, an unworn left second upper molar (LM2) discovered in 1958 in Bambino's Cave (near Santa Maria di Leuca, Apulia, Italy) and attributed to Homo neanderthalensis. Our study includes comparisons of standard metric and nonmetric data, a 2D image analysis of the occlusal surface and measurements of both 2D and 3D enamel thickness and dental tissue proportions. Although Leuca I follows the Neandertal M2s trend in some morphometric aspects (i.e., small relative occlusal polygon area), in other cases it falls to the higher end (for 3D average enamel thickness) or even outside (for 3D‐relative enamel thickness) the Neandertal M2 variability, thus increasing the known Neandertal range of variation. Am J Phys Anthropol 152:300–305, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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6.
Synonymy of two genus-group names is substantiated: Tricholicinus Poppius, 1912 (type species: Tricholicinus setosus J.R. Sahlberg, 1880) = Martyr Semenov et Znojko, 1929 (type species: Martyr praeteritorum Semenov et Znojko, 1929), syn. n. and Psammodromius Peyerimhoff, 1927 (type species: Psammodromius noctivagus Peyerimhoff, 1927) = Xanthomelina Iablokoff-Khnzorian, 1964 (type species: Apristus zajtzewi Eichler, 1924), syn. n. Synonymy of the following names of the species-group taxa is established: Calosoma (Callisthenes) elegans (Kirsch, 1859) = C. (Callisthenes) declive (Dohrn, 1884), syn. n., lectotype of the latter is designated; Carabus (Semnocarabus) erosus erosus Motschulsky, 1866 = C. (Semnocarabus) erosus karascharensis (Eidam, 1931), syn. n., lectotype of the latter is designated; C. (Semnocarabus) cicatricosulus pseudoerosus Mandl, 1955 = C. (Semnocarabus) bogdanowi semnocosulus Deuve et Tian, 2013, syn. n.; Chlaenius (Dinodes) viridis (Ménétriés, 1832) = Ch. pallidicornis Ballion, 1871, syn. n.; Licinus (Tricholicinus) setosus (J.R. Sahlberg, 1880) = Licinus mongolicus Reitter, 1900, syn. n. = Martyr praeteritorum Semenov et Znojko, 1929, syn. n. = Martyr alter Semenov et Znojko, 1929, syn. n.; Psammodromius zajtzewi (Eichler, 1924), comb. n. (transferred from the genus Xanthomelina Iablokoff-Khnzorian, 1964) = Psammodromius pallidicolor (Mandl, 1973), syn. n. = Psammodromius damanabii Morvan, 1977, syn. n.Calosoma (Callisthenes) rostislavi Semenov, 1906, stat. resurr. is resurrected from synonyms of C. (Callisthenes) declive (Dohrn, 1884).  相似文献   
7.
A theoretical model of calcium signaling is presented that simulates oscillations of cytoplasmic calcium concentration ([Ca2+]cyt) in stomatal guard cells under the action of abscisic acid. The model is based on the kinetics of inositol 1,4,5-trisphosphate-sensitive calcium channels of endoplasmic reticulum and cyclic ADP-ribose-sensitive calcium channels of the tonoplast. The operation of two energy-dependent pumps—the Ca2+-ATPase of the endoplasmic reticulum and the Ca2+/H+ antiporter of the tonoplast—is also included in the model. It is shown that the removal of excessive Ca2+ from the cytoplasm by the tonoplast Ca2+/H+ antiporter is the main factor accounting for generation of [Ca2+]cyt oscillations at a wide range of ABA concentrations (0.01–1 M). The long period of [Ca2+]cyt oscillations in plant cells is explained by a slow release from inhibition of inositol 1,4,5-trisphosphate-gated calcium channels.  相似文献   
8.
Several new models of intracellular calcium dynamics based on refined inositol-1,4,5-triphosphate-sensitive calcium channel kinetics were studied. The refined kinetic schemes take into account that a cytosolic calcium cannot inhibit inositol-1,4,5-triphosphate receptors when they are bound to inositol-1,4,5-triphosphate. The mathematical analysis of intracellular calcium dynamics based on one of these schemes allowed us to show how different types of Ca response to extracellular stimuli, such as excitability, oscillations, sustained elevation of Ca and frequency encoding can arise with a reasonably good fit to experimental data.  相似文献   
9.
(–)-Hydroxycitric acid (HCA), a natural extract from the dried fruit rind of Garcinia cambogia (family Guttiferae), is a popular supplement for weight management. The dried fruit rind has been used for centuries as a condiment in Southeastern Asia to make food more filling and satisfying. A significant number of studies highlight the efficacy of Super CitriMax (HCA-SX, a novel 60% calcium-potassium salt of HCA derived from Garcinia cambogia) in weight management. These studies also demonstrate that HCA-SX promotes fat oxidation, inhibits ATP-citrate lyase (a building block for fat synthesis), and lowers the level of leptin in obese subjects. Acute oral, acute dermal, primary dermal irritation and primary eye irritation toxicity studies have demonstrated the safety of HCA-SX. However, no long-term safety of HCA-SX or any other (–)-hydroxycitric acid extract has been previously assessed. In this study, we have evaluated the dose- and time-dependent effects of HCA-SX in Sprague-Dawley rats on body weight, hepatic and testicular lipid peroxidation, DNA fragmentation, liver and testis weight, expressed as such and as a % of body weight and brain weight, and histopathological changes over a period of 90 days. The animals were treated with 0, 0.2, 2.0 and 5.0% HCA-SX as feed intake and the animals were sacrificed on 30, 60 or 90 days of treatment. The feed and water intake were assessed and correlated with the reduction in body weight. HCA-SX supplementation demonstrated a reduction in body weight in both male and female rats over a period of 90 days as compared to the corresponding control animals. An advancing age-induced marginal increase in hepatic lipid peroxidation was observed in both male and female rats as compared to the corresponding control animals. However, no such difference in hepatic DNA fragmentation and testicular lipid peroxidation and DNA fragmentation was observed. Furthermore, liver and testis weight, expressed as such and as a percentage of body weight and brain weight, at 30, 60 and 90 days of treatment, exhibited no significant difference between the four groups. Taken together, these results indicate that treatment of HCA-SX over a period of 90 days results in a reduction in body weight, but did not cause any changes in hepatic and testicular lipid peroxidation, DNA fragmentation, or histopathological changes.  相似文献   
10.
The impetus for the novel Energy Formula (EF) which combines the niacin-bound chromium (III) (0.45%) (NBC), standardized extract of Withania somnifera extracts (10.71%), caffeine (22.76%), D-ribose (10.71%) and selected amino acids such as phenylalanine, taurine and glutamine (55.37%) was based on the knowledge of the cardioprotective potentials of the Withania somnifera extract, caffeine and D-ribose as well as their abilities to increase energy levels and the abilities of amino acids to increase the muscle mass and energy levels. The effect of oral supplementation of EF on the safety, myocardial energy levels and cardioprotective ability were investigated in an ischemic-reperfused myocardium model in both male and female Sprague-Dawley rats over 90 days trial period. At the completion of 90 days, the EF-treated male and female rats gained 9.4% and 3.1% less body weights, respectively, as compared to their corresponding control groups. No significant difference was found in the levels of lipid peroxidation and activities of hepatic Aspartate transaminase, Alanine transaminase and Alkaline phosphatase in EF treatment when compared with control animals. The male and female rat hearts were subjected to 30 min of global ischemia followed by 2 h of reperfusion at 30 and 90 days of EF treatment. Cardiovascular functions including heart rate, coronary flow, aortic flow, dp/dt(max), left ventricular developed pressure (LVDP) and infarct size were monitored. The levels of myocardial adenosine triphosphate (ATP), creatine phosphate (CP), phospho-adenosine monophosphate kinase (p-AMPK) levels, were analyzed at the end of 30 and 90 days of treatment. Significant improvement was observed in all parameters in the EF treatment groups as compared to their corresponding controls. Thus the niacin-bound chromium (III) based energy formula is safe and effective supplement to boost energy levels and cardioprotection.  相似文献   
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