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31.
Chirag Shah Michael J. W. VanGompel Villian Naeem Yanmei Chen Terrance Lee Nicholas Angeloni Yin Wang Eugene Yujun Xu 《PLoS genetics》2010,6(7)
Sex-specific traits that lead to the production of dimorphic gametes, sperm in males and eggs in females, are fundamental for sexual reproduction and accordingly widespread among animals. Yet the sex-biased genes that underlie these sex-specific traits are under strong selective pressure, and as a result of adaptive evolution they often become divergent. Indeed out of hundreds of male or female fertility genes identified in diverse organisms, only a very small number of them are implicated specifically in reproduction in more than one lineage. Few genes have exhibited a sex-biased, reproductive-specific requirement beyond a given phylum, raising the question of whether any sex-specific gametogenesis factors could be conserved and whether gametogenesis might have evolved multiple times. Here we describe a metazoan origin of a conserved human reproductive protein, BOULE, and its prevalence from primitive basal metazoans to chordates. We found that BOULE homologs are present in the genomes of representative species of each of the major lineages of metazoans and exhibit reproductive-specific expression in all species examined, with a preponderance of male-biased expression. Examination of Boule evolution within insect and mammalian lineages revealed little evidence for accelerated evolution, unlike most reproductive genes. Instead, purifying selection was the major force behind Boule evolution. Furthermore, loss of function of mammalian Boule resulted in male-specific infertility and a global arrest of sperm development remarkably similar to the phenotype in an insect boule mutation. This work demonstrates the conservation of a reproductive protein throughout eumetazoa, its predominant testis-biased expression in diverse bilaterian species, and conservation of a male gametogenic requirement in mice. This shows an ancient gametogenesis requirement for Boule among Bilateria and supports a model of a common origin of spermatogenesis. 相似文献
32.
M. Nasir Khan Manzer H. Siddiqui F. Mohammad M. Naeem M. Masroor A. Khan 《Acta Physiologiae Plantarum》2010,32(1):121-132
Salinity stress affects many metabolic facets of plants and induces anatomical and morphological changes resulting in reduced growth and productivity. To overcome the damaging effects of salinity, different strategies of the application of nutrients with plant hormones are being adopted. The present study was carried out with an aim to find out whether application of calcium chloride (CaCl2) and gibberellic acid (GA3) could alleviate the detrimental effects of salinity stress on plant metabolism. Fifteen days old plants were supplied with (1) 0 mM NaCl + 0 mg CaCl2 kg?1 sand + 0 M GA3 (control, T0); (2) 0 mM NaCl + 10 mg CaCl2 kg?1 sand + 0 M GA3 (T1); (3) 0 mM NaCl + 0 mg CaCl2 kg?1 sand + 10?6 M GA3 (T2); (4) 150 mM NaCl + 0 mg CaCl2 kg?1 sand + 0 M GA3 (T3); (5) 150 mM NaCl + 10 mg CaCl2 kg?1 sand + 0 M GA3 (T4); (6) 150 mM NaCl + 0 mg CaCl2 kg?1 sand + 10?6 M GA3 (T5); (7) 150 mM NaCl + 10 mg CaCl2 kg?1 sand + 10?6 M GA3 (T6). To assess the response of the crop to NaCl, CaCl2 and GA3, plants were uprooted randomly at 60 days after sowing. The presence of NaCl in the growth medium decreased all the growth and physio-biochemical parameters, except electrolyte leakage, proline (Pro) and glycine betaine (GB) content, thiobarbituric acid reactive substances (TBARS), H2O2 content, activities of superoxide dismutase (SOD) and catalase (CAT) and leaf Na content, which exhibited an increase of 37.6, 29.3, 366.9, 107.5, 59.1, 17.1, 28.4 and 255.2%, respectively, compared to the control plants. However, application of CaCl2 in combination with GA3 appears to confer greater osmoprotection by the additive role with NaCl in Pro and GB accumulation. Although the activities of antioxidant enzymes (SOD, CAT and POX) were increased by salt stress, the combined application of CaCl2 and GA3 to salt-stressed plants further enhanced the activities of these enzymes by 25.1, 6.7 and 47.8%, respectively, compared to plants grown with NaCl alone. The present study showed that application of CaCl2 and GA3 alone as well as in combination mitigated the adverse effect of salinity, but combined application of these treatments proved more effective in alleviating the adverse effects of NaCl stress. 相似文献
33.
Aisha Khan 《American anthropologist》2000,102(1):197-199
Women Plantation Workers: International Experiences. Shobhita Jain and Rhoda Reddock. eds. New York: Berg. 1998.186 pp. 相似文献
34.
In our previous publication we had reported the purification and characterization of Clitoria ternatea agglutinin from its seeds on fetuin CL agarose affinity column, designated CTA [A. Naeem, S. Haque, R.H. Khan. Protein J., 2007]. Since CTA binds beta-d-galactosides, this lectin can be used as valuable tool for glycobiology studies in biomedical and cancer research. So an attempt was made for a high yielding alternative purification method employing the use of asialofetuin CL agarose column for the above-mentioned lectin, designated CTL. The fetuin affinity purified agglutinin was found similar to asialofetuin affinity purified lectin in SDS pattern, HPLC and N-terminal sequence. The content of lectin was found to be 30mg/30g dry weight of pulse. The yield was 2.8% as compared to 0.3% obtained on fetuin column. The number of tryptophan and tyrosine estimated was four and six per subunit. 相似文献
35.
Inflammatory bowel diseases (IBD) such as Crohn’s disease and ulcerative colitis are inflammatory disorders associated with
decreased colonic contractility. Here we show that, in experimental colitis in rat induced by trinitrobenzenesulfonic acid,
there is a decrease in contraction in response to carbamoylcholine and the sarco/endoplasmic reticulum Ca+2 (SERCA) pump inhibitor thapsigargin. However, the decrease in contractility may occur due to decrease in the SERCA pump levels
or their inactivation. Therefore, we examined the protein and mRNA levels for SERCA2 isoform, which is predominant isoform
in colonic smooth muscle. There was a decrease in the levels of SERCA2 protein and mRNA levels in inflamed colonic muscle.
These findings suggest that decreased SERCA pump levels is responsible for a decrease in the Ca+2 stores in the sarco/endoplasmic reticulum that causes a decrease in the contractility in colonic smooth muscle leading to
poor bowel movements. 相似文献
36.
Tauqeer Ahmad Yasir Sobia Aslam Muhammad Shahid Rizwan Allah Wasaya Muhammad Ateeq Muhammad Naeem Khan Sikander Khan Tanveer Walid Soufan Basharat Ali Allah Ditta Arpna Kumari Ayman EL Sabagh 《Phyton》2022,91(11):2491-2504
In soil biota, higher and enduring concentration of heavy metals like cadmium (Cd) is hazardous and associated
with great loss in growth, yield, and quality parameters of most of the crop plants. Recently, in-situ applications of
eco-friendly stabilizing agents in the form of organic modifications have been utilized to mitigate the adverse
effects of Cd-toxicity. This controlled experiment was laid down to appraise the imprints of various applied
organic amendments namely poultry manure (PM), farmyard manure (FYM), and sugarcane press mud (PS)
to immobilize Cd in polluted soil. Moreover, phytoavailability of Cd in wheat was also accessed under an alkaline
environment. Results revealed that the addition of FYM (5–10 ton ha-1
) in Cd-contaminated soil significantly
increased germination rate, leaf chlorophyll content, plant height, spike length, biological and grain yield amongst
all applied organic amendments. Moreover, the addition of FYM (5–10 ton ha-1
) also reduced the phytoavailability of Cd by 73–85% in the roots, 57–83% in the shoots, and 81–90% in grains of wheat crop. Thus, it is affirmed
that incorporation of FYM (5–10 ton ha-1
) performed better to enhance wheat growth and yield by remediating
Cd. Thus, the application of FYM (5–10 ton ha-1
) reduced the toxicity induced by Cd to plants by declining its
uptake and translocation as compared to all other applied organic amendments to immobilize Cd under sandy
alkaline polluted soil. 相似文献
37.
Qasim Ayub Massimo Mezzavilla Luca Pagani Marc Haber Aisha Mohyuddin Shagufta Khaliq Syed?Qasim Mehdi Chris Tyler-Smith 《American journal of human genetics》2015,96(5):775-783
The Kalash represent an enigmatic isolated population of Indo-European speakers who have been living for centuries in the Hindu Kush mountain ranges of present-day Pakistan. Previous Y chromosome and mitochondrial DNA markers provided no support for their claimed Greek descent following Alexander III of Macedon''s invasion of this region, and analysis of autosomal loci provided evidence of a strong genetic bottleneck. To understand their origins and demography further, we genotyped 23 unrelated Kalash samples on the Illumina HumanOmni2.5M-8 BeadChip and sequenced one male individual at high coverage on an Illumina HiSeq 2000. Comparison with published data from ancient hunter-gatherers and European farmers showed that the Kalash share genetic drift with the Paleolithic Siberian hunter-gatherers and might represent an extremely drifted ancient northern Eurasian population that also contributed to European and Near Eastern ancestry. Since the split from other South Asian populations, the Kalash have maintained a low long-term effective population size (2,319–2,603) and experienced no detectable gene flow from their geographic neighbors in Pakistan or from other extant Eurasian populations. The mean time of divergence between the Kalash and other populations currently residing in this region was estimated to be 11,800 (95% confidence interval = 10,600−12,600) years ago, and thus they represent present-day descendants of some of the earliest migrants into the Indian sub-continent from West Asia. 相似文献
38.
Kafeel Ahmad Asma Ashfaq Muhammad Ashraf Nudrat Aisha Akram Sumaira Yasmin 《人类与生态风险评估》2015,21(4):1109-1122
Dietary exposure to heavy metals (viz., Ni, As, Fe, Cr, Mn, Co, Mo, Cu, Zn, Se, Cd, and Pb) has been recognized as a potential hazard to human health. This study investigates the level of contamination at two different sites in Pakistan, one irrigated with canal water (Site-I) and the other with urban wastewater (Site-II). At Site-II, irrigation with wastewater resulted in a significant increase in heavy metals and metalloids in soil and a subsequent build-up in two vegetables selected for study (Solanum tuberosum [potato] and Pisum sativum [pea]). Results showed that mean concentrations of heavy metals and metalloids in soil at Site-I were lower than those of Site-II. Mean concentrations of As and Cd in soil at both sites and for both vegetables were found above maximum permissible levels, while for both vegetables As at both sites and Cd, Mo, and Pb exceeded the suggested maximum levels for vegetables. High levels of some metals in the soils and vegetables could be due to unnecessary use of fertilizers and disposable water for irrigating the soils and the environmental cues prevalent in the areas, such as presence of ions that may bind the metals, often play an important role in uptake. 相似文献
39.
Aasim I. Padela Aisha Y. Malik Farr Curlin Raymond De Vries 《Developing world bioethics》2015,15(2):98-106
Contemporary clinical ethics was founded on principlism, and the four principles: respect for autonomy, nonmaleficence, beneficence and justice, remain dominant in medical ethics discourse and practice. These principles are held to be expansive enough to provide the basis for the ethical practice of medicine across cultures. Although principlism remains subject to critique and revision, the four‐principle model continues to be taught and applied across the world. As the practice of medicine globalizes, it remains critical to examine the extent to which both the four‐principle framework, and individual principles among the four, suffice patients and practitioners in different social and cultural contexts. Using the four‐principle model we analyze two accounts of surrogate decision making – one from the developed and one from the developing world – in which the clinician undertakes medical decision‐making with apparently little input from the patient and/or family. The purpose of this analysis is to highlight challenges in assessing ethical behaviour according to the principlist model. We next describe cultural expectations and mores that inform both patient and clinician behaviors in these scenarios in order to argue that the principle of respect for persons informed by culture‐specific ideas of personhood may offer an improved ethical construct for analyzing and guiding medical practice in a globalized and plural world. 相似文献
40.
Aysha H Khan Muniba Aban Jamal Raza Naeem ul Haq Abdul Jabbar Tariq Moatter 《BMC endocrine disorders》2011,11(1):1-6