742 resultados para BF
Resumo:
The Body Mass Index (BMI) has been used worldwide as an indicator of fatness. However, the universal cut-off points by the World Health Organisation (WHO) classification may not be appropriate for every ethnic group when consider the relationship with their actual total body fatness(%BF). The application of population-specific classifications to assess BMI may be more relevant to public health. Ethnic differences in the BMI%BF relationship between 45 Japanese and 42 Australian-Caucasian males were assessed using whole body dual-energy X-ray absorptiometry (DXA) scan and anthropometry using a standard protocol. Japanese males had significantly (p<0.05) greater %BF at given BMI values than Australian males. When this is taken into account the newly proposed Asia-Pacific BMI classification of BMI 23 as overweight and 25 as obese may better assess the level of obesity that is associated increased health risks for this population. To clarify the current findings, further studies that compare the relationships across other Japanese populations are recommended.
Resumo:
一种金环蛇抗菌肽cathelicidin-BF及其基因和应用,属生物医学领域。 Cathelicidin-BF是一种直链多肽,含有三十个氨基酸残基,分子量3637.54Da,等电点11.79。cathelicidin-BF全序列为:赖氨酸-苯丙氨酸-苯丙氨酸-精氨酸-赖氨酸-亮氨酸-赖氨酸-赖氨酸-丝氨酸-缬氨酸-赖氨酸-赖氨酸 -精氨酸-丙氨酸-赖氨酸-谷氨酸-苯丙氨酸-苯丙氨酸-赖氨酸-赖氨酸 -脯氨酸-精氨酸-缬氨酸-异亮氨酸-甘氨酸-缬氨酸-丝氨酸-异亮氨酸 -脯氨酸-苯丙氨酸。编码cathelicidin-BF的基因由750个核苷酸组成,其中编码成熟肽部分的为第484-573位核苷酸。Cathelicidin-BF分子量小、杀菌作用强、作用时间迅速、对多种临床耐药菌有非常强的杀灭作用。此外还具有广谱抗菌和非盐依赖等有益特点。
Resumo:
本发明涉及一种金环蛇抗菌肽cathelicidin-BF变异体cathelicidin- BF15及其应用,属于生物医学领域。金环蛇抗菌肽cathelicidin-BF变异体 cathelicidin-BF15是一种直链多肽,含有15个氨基酸残基,分子量1939.47Da,等电点12.05。cathelicidin-BF15全序列为:缬氨酸-赖氨酸-精氨酸-苯丙氨酸-赖氨酸-赖氨酸-苯丙氨酸-苯丙氨酸-精氨酸-赖氨酸-亮氨酸-赖氨酸-赖氨酸-丝氨酸-缬氨酸。cathelicidin-BF15具有强烈的杀菌作用,对多种临床耐药菌有非常强的杀灭作用,此外具有结构简单,人工合成方便和广谱抗菌等有益特点。
Resumo:
Cathelicidins是动物体内一个具有多功能的抗菌肽家族,目前仅在哺乳类、鸟类、爬行类和鱼类中有发现。Cathelicidins具有广谱的抗微生物活性,不但对普通革兰氏阳性细菌、革兰氏阴性细菌、真菌以及病毒具有非常强的活性,而且对许多临床耐药微生物同样具有作用。除此之外,cathelicidins具有许多其他生物学活性,如对多种免疫细胞具有趋化作用、诱导肥大细胞脱粒和组织胺释放、调节巨噬细胞转录、促进伤口愈合、诱导血管发生、诱导变异细胞系细胞凋亡和淋巴细胞活化等。 金环蛇(Bungarus fasciatus)属于眼镜蛇科(Elapinae)环蛇属(Bungarus),是一种具有前沟牙的毒蛇,广泛分布于我国广东、广西、福建、江西、海南及云南南部。 在本论文中,我们对金环蛇体内cathelicidins家族抗菌肽cathelicidin-BF进行了一系列研究。 通过凝胶过滤、阳离子交换和反相高压液相三步从金环蛇蛇毒冻干粉中分离纯化得到金环蛇cathelicidins家族抗菌肽,命名为cathelicidin-BF。Edman降解法测定其氨基酸序列为KFFRKLKKSVKKRAKEFFKKPRVIGVSIPF,由30个氨基酸残基组成,ESI-MS测得其分子量为3637.5 Da。 构建了金环蛇毒腺cDNA文库,从中克隆得到了编码cathelicidin-BF前体的cDNA序列。该cDNA序列长度为750 bp,由此推断出的cathelicidin-BF前体由191个氨基酸残基组成,包括信号肽区、保守的cathelin区和成熟肽区三部分。用RT-PCR的方法对cathelicidin-BF的组织表达情况进行了研究,结果表明cathelicidin-BF在金环蛇胃、气管、皮肤、肌肉、心脏、肾脏、肺、脑、小肠、脾脏、肝脏、卵巢、毒腺中均有表达,但各组织表达量存在差异。进化分析表明,金环蛇cathelicidin-BF与鸭嘴兽CATH-3在系统进化树中独立成簇,表明金环蛇与鸭嘴兽有着一定的亲缘关系,这为鸭嘴兽在动物进化中分类地位的确定提供了参考资料。 对cathelicidin-BF可能具有的各种生物学活性进行了研究。Cathelicidin-BF具有广谱的抗微生物活性,对革兰氏阳性细菌、革兰氏阴性细菌和真菌均有活性,Cathelicidins是动物体内一个具有多功能的抗菌肽家族,目前仅在哺乳类、鸟类、爬行类和鱼类中有发现。Cathelicidins具有广谱的抗微生物活性,不但对普通革兰氏阳性细菌、革兰氏阴性细菌、真菌以及病毒具有非常强的活性,而且对许多临床耐药微生物同样具有作用。除此之外,cathelicidins具有许多其他生物学活性,如对多种免疫细胞具有趋化作用、诱导肥大细胞脱粒和组织胺释放、调节巨噬细胞转录、促进伤口愈合、诱导血管发生、诱导变异细胞系细胞凋亡和淋巴细胞活化等。 金环蛇(Bungarus fasciatus)属于眼镜蛇科(Elapinae)环蛇属(Bungarus),是一种具有前沟牙的毒蛇,广泛分布于我国广东、广西、福建、江西、海南及云南南部。 在本论文中,我们对金环蛇体内cathelicidins家族抗菌肽cathelicidin-BF进行了一系列研究。 通过凝胶过滤、阳离子交换和反相高压液相三步从金环蛇蛇毒冻干粉中分离纯化得到金环蛇cathelicidins家族抗菌肽,命名为cathelicidin-BF。Edman降解法测定其氨基酸序列为KFFRKLKKSVKKRAKEFFKKPRVIGVSIPF,由30个氨基酸残基组成,ESI-MS测得其分子量为3637.5 Da。 构建了金环蛇毒腺cDNA文库,从中克隆得到了编码cathelicidin-BF前体的cDNA序列。该cDNA序列长度为750 bp,由此推断出的cathelicidin-BF前体由191个氨基酸残基组成,包括信号肽区、保守的cathelin区和成熟肽区三部分。用RT-PCR的方法对cathelicidin-BF的组织表达情况进行了研究,结果表明cathelicidin-BF在金环蛇胃、气管、皮肤、肌肉、心脏、肾脏、肺、脑、小肠、脾脏、肝脏、卵巢、毒腺中均有表达,但各组织表达量存在差异。进化分析表明,金环蛇cathelicidin-BF与鸭嘴兽CATH-3在系统进化树中独立成簇,表明金环蛇与鸭嘴兽有着一定的亲缘关系,这为鸭嘴兽在动物进化中分类地位的确定提供了参考资料。 对cathelicidin-BF可能具有的各种生物学活性进行了研究。Cathelicidin-BF具有广谱的抗微生物活性,对革兰氏阳性细菌、革兰氏阴性细菌和真菌均有活性,Cathelicidins是动物体内一个具有多功能的抗菌肽家族,目前仅在哺乳类、鸟类、爬行类和鱼类中有发现。Cathelicidins具有广谱的抗微生物活性,不但对普通革兰氏阳性细菌、革兰氏阴性细菌、真菌以及病毒具有非常强的活性,而且对许多临床耐药微生物同样具有作用。除此之外,cathelicidins具有许多其他生物学活性,如对多种免疫细胞具有趋化作用、诱导肥大细胞脱粒和组织胺释放、调节巨噬细胞转录、促进伤口愈合、诱导血管发生、诱导变异细胞系细胞凋亡和淋巴细胞活化等。 金环蛇(Bungarus fasciatus)属于眼镜蛇科(Elapinae)环蛇属(Bungarus),是一种具有前沟牙的毒蛇,广泛分布于我国广东、广西、福建、江西、海南及云南南部。 在本论文中,我们对金环蛇体内cathelicidins家族抗菌肽cathelicidin-BF进行了一系列研究。 通过凝胶过滤、阳离子交换和反相高压液相三步从金环蛇蛇毒冻干粉中分离纯化得到金环蛇cathelicidins家族抗菌肽,命名为cathelicidin-BF。Edman降解法测定其氨基酸序列为KFFRKLKKSVKKRAKEFFKKPRVIGVSIPF,由30个氨基酸残基组成,ESI-MS测得其分子量为3637.5 Da。 构建了金环蛇毒腺cDNA文库,从中克隆得到了编码cathelicidin-BF前体的cDNA序列。该cDNA序列长度为750 bp,由此推断出的cathelicidin-BF前体由191个氨基酸残基组成,包括信号肽区、保守的cathelin区和成熟肽区三部分。用RT-PCR的方法对cathelicidin-BF的组织表达情况进行了研究,结果表明cathelicidin-BF在金环蛇胃、气管、皮肤、肌肉、心脏、肾脏、肺、脑、小肠、脾脏、肝脏、卵巢、毒腺中均有表达,但各组织表达量存在差异。进化分析表明,金环蛇cathelicidin-BF与鸭嘴兽CATH-3在系统进化树中独立成簇,表明金环蛇与鸭嘴兽有着一定的亲缘关系,这为鸭嘴兽在动物进化中分类地位的确定提供了参考资料。 对cathelicidin-BF可能具有的各种生物学活性进行了研究。Cathelicidin-BF具有广谱的抗微生物活性,对革兰氏阳性细菌、革兰氏阴性细菌和真菌均有活性,Cathelicidins是动物体内一个具有多功能的抗菌肽家族,目前仅在哺乳类、鸟类、爬行类和鱼类中有发现。Cathelicidins具有广谱的抗微生物活性,不但对普通革兰氏阳性细菌、革兰氏阴性细菌、真菌以及病毒具有非常强的活性,而且对许多临床耐药微生物同样具有作用。除此之外,cathelicidins具有许多其他生物学活性,如对多种免疫细胞具有趋化作用、诱导肥大细胞脱粒和组织胺释放、调节巨噬细胞转录、促进伤口愈合、诱导血管发生、诱导变异细胞系细胞凋亡和淋巴细胞活化等。 金环蛇(Bungarus fasciatus)属于眼镜蛇科(Elapinae)环蛇属(Bungarus),是一种具有前沟牙的毒蛇,广泛分布于我国广东、广西、福建、江西、海南及云南南部。 在本论文中,我们对金环蛇体内cathelicidins家族抗菌肽cathelicidin-BF进行了一系列研究。 通过凝胶过滤、阳离子交换和反相高压液相三步从金环蛇蛇毒冻干粉中分离纯化得到金环蛇cathelicidins家族抗菌肽,命名为cathelicidin-BF。Edman降解法测定其氨基酸序列为KFFRKLKKSVKKRAKEFFKKPRVIGVSIPF,由30个氨基酸残基组成,ESI-MS测得其分子量为3637.5 Da。 构建了金环蛇毒腺cDNA文库,从中克隆得到了编码cathelicidin-BF前体的cDNA序列。该cDNA序列长度为750 bp,由此推断出的cathelicidin-BF前体由191个氨基酸残基组成,包括信号肽区、保守的cathelin区和成熟肽区三部分。用RT-PCR的方法对cathelicidin-BF的组织表达情况进行了研究,结果表明cathelicidin-BF在金环蛇胃、气管、皮肤、肌肉、心脏、肾脏、肺、脑、小肠、脾脏、肝脏、卵巢、毒腺中均有表达,但各组织表达量存在差异。进化分析表明,金环蛇cathelicidin-BF与鸭嘴兽CATH-3在系统进化树中独立成簇,表明金环蛇与鸭嘴兽有着一定的亲缘关系,这为鸭嘴兽在动物进化中分类地位的确定提供了参考资料。 对cathelicidin-BF可能具有的各种生物学活性进行了研究。Cathelicidin-BF具有广谱的抗微生物活性,对革兰氏阳性细菌、革兰氏阴性细菌和真菌均有活性,Cathelicidins是动物体内一个具有多功能的抗菌肽家族,目前仅在哺乳类、鸟类、爬行类和鱼类中有发现。Cathelicidins具有广谱的抗微生物活性,不但对普通革兰氏阳性细菌、革兰氏阴性细菌、真菌以及病毒具有非常强的活性,而且对许多临床耐药微生物同样具有作用。除此之外,cathelicidins具有许多其他生物学活性,如对多种免疫细胞具有趋化作用、诱导肥大细胞脱粒和组织胺释放、调节巨噬细胞转录、促进伤口愈合、诱导血管发生、诱导变异细胞系细胞凋亡和淋巴细胞活化等。 金环蛇(Bungarus fasciatus)属于眼镜蛇科(Elapinae)环蛇属(Bungarus),是一种具有前沟牙的毒蛇,广泛分布于我国广东、广西、福建、江西、海南及云南南部。 在本论文中,我们对金环蛇体内cathelicidins家族抗菌肽cathelicidin-BF进行了一系列研究。 通过凝胶过滤、阳离子交换和反相高压液相三步从金环蛇蛇毒冻干粉中分离纯化得到金环蛇cathelicidins家族抗菌肽,命名为cathelicidin-BF。Edman降解法测定其氨基酸序列为KFFRKLKKSVKKRAKEFFKKPRVIGVSIPF,由30个氨基酸残基组成,ESI-MS测得其分子量为3637.5 Da。 构建了金环蛇毒腺cDNA文库,从中克隆得到了编码cathelicidin-BF前体的cDNA序列。该cDNA序列长度为750 bp,由此推断出的cathelicidin-BF前体由191个氨基酸残基组成,包括信号肽区、保守的cathelin区和成熟肽区三部分。用RT-PCR的方法对cathelicidin-BF的组织表达情况进行了研究,结果表明cathelicidin-BF在金环蛇胃、气管、皮肤、肌肉、心脏、肾脏、肺、脑、小肠、脾脏、肝脏、卵巢、毒腺中均有表达,但各组织表达量存在差异。进化分析表明,金环蛇cathelicidin-BF与鸭嘴兽CATH-3在系统进化树中独立成簇,表明金环蛇与鸭嘴兽有着一定的亲缘关系,这为鸭嘴兽在动物进化中分类地位的确定提供了参考资料。 对cathelicidin-BF可能具有的各种生物学活性进行了研究。Cathelicidin-BF具有广谱的抗微生物活性,对革兰氏阳性细菌、革兰氏阴性细菌和真菌均有活性,Cathelicidins是动物体内一个具有多功能的抗菌肽家族,目前仅在哺乳类、鸟类、爬行类和鱼类中有发现。Cathelicidins具有广谱的抗微生物活性,不但对普通革兰氏阳性细菌、革兰氏阴性细菌、真菌以及病毒具有非常强的活性,而且对许多临床耐药微生物同样具有作用。除此之外,cathelicidins具有许多其他生物学活性,如对多种免疫细胞具有趋化作用、诱导肥大细胞脱粒和组织胺释放、调节巨噬细胞转录、促进伤口愈合、诱导血管发生、诱导变异细胞系细胞凋亡和淋巴细胞活化等。 金环蛇(Bungarus fasciatus)属于眼镜蛇科(Elapinae)环蛇属(Bungarus),是一种具有前沟牙的毒蛇,广泛分布于我国广东、广西、福建、江西、海南及云南南部。 在本论文中,我们对金环蛇体内cathelicidins家族抗菌肽cathelicidin-BF进行了一系列研究。 通过凝胶过滤、阳离子交换和反相高压液相三步从金环蛇蛇毒冻干粉中分离纯化得到金环蛇cathelicidins家族抗菌肽,命名为cathelicidin-BF。Edman降解法测定其氨基酸序列为KFFRKLKKSVKKRAKEFFKKPRVIGVSIPF,由30个氨基酸残基组成,ESI-MS测得其分子量为3637.5 Da。 构建了金环蛇毒腺cDNA文库,从中克隆得到了编码cathelicidin-BF前体的cDNA序列。该cDNA序列长度为750 bp,由此推断出的cathelicidin-BF前体由191个氨基酸残基组成,包括信号肽区、保守的cathelin区和成熟肽区三部分。用RT-PCR的方法对cathelicidin-BF的组织表达情况进行了研究,结果表明cathelicidin-BF在金环蛇胃、气管、皮肤、肌肉、心脏、肾脏、肺、脑、小肠、脾脏、肝脏、卵巢、毒腺中均有表达,但各组织表达量存在差异。进化分析表明,金环蛇cathelicidin-BF与鸭嘴兽CATH-3在系统进化树中独立成簇,表明金环蛇与鸭嘴兽有着一定的亲缘关系,这为鸭嘴兽在动物进化中分类地位的确定提供了参考资料。 对cathelicidin-BF可能具有的各种生物学活性进行了研究。Cathelicidin-BF具有广谱的抗微生物活性,对革兰氏阳性细菌、革兰氏阴性细菌和真菌均有活性,其中包括大量临床分离耐药菌株。Cathelicidin-BF对革兰氏阴性细菌的活性要强于革兰氏阳性细菌,此外对白色念珠菌、毕赤酵母和一些腐生性真菌也具有活性。Cathelicidin-BF的抗氧化活性、溶血活性、凝集素活性、丝氨酸蛋白酶和丝氨酸蛋白酶抑制剂活性、细胞毒性、抗肿瘤活性均不明显。Cathelicidin-BF具有很强的肥大细胞脱颗粒活性。以上结果表明cathelicidin-BF在金环蛇抵御外界病原微生物侵袭的先天免疫反应中可能发挥了重要作用。 利用多种实验方法对cathelicidin-BF的结构和抗菌机理进行了研究。CD和NMR的实验结果表明,在亲水环境中,cathelicidin-BF为无规卷曲的构象;在疏水或模拟细菌细胞质膜的环境中,cathelicidin-BF的N-末端区域具有典型的两亲性α-螺旋构象。杀菌动力学实验结果表明,cathelicidin-BF杀菌作用极其迅速,在浓度大于1×MIC时,在1 min内即可杀死所有细菌,且其杀菌作用是致死性的。扫描电镜结果表明,经过cathelicidin-BF处理的细菌细胞形状发生明显改变,细胞膨胀变形,表面出现大量囊泡状结构。大量细菌细胞破裂溶解,内容物外泄。综合以上结果我们推测:cathelicidin-BF在亲水的环境中为无规卷曲的结构,当通过静电相互作用吸附到细菌细胞质膜上后,由于环境疏水性的增加其N-端转变为两亲性的α-螺旋构象。Cathelicidin-BF的疏水侧插入到细菌细胞质膜内部,亲水侧暴露于细菌细胞质膜表面。随着结合到细菌细胞质膜上的cathelicidin-BF分子不断增加,细菌细胞质膜内陷,最终在细菌细胞质膜上形成孔洞。细菌细胞内容物大量外流,最终导致细菌细胞的死亡。 通过体外和体内多个实验对cathelicidin-BF进行了初步的药理学和药效学研究。Cathelicidin-BF在血清中稳定性较差,容易被血清中各种蛋白酶降解。一定浓度的盐离子能够增强cathelicidin-BF的抗菌活性。动物模型实验表明,cathelicidin-BF对多种细菌引起的小鼠皮肤感染具有很好的治疗效果。Cathelicidin-BF本身所具有的特点及动物模型实验中表现出的极佳的治疗效果使其成为外用抗菌药物开发的优良模板。
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于2010-11-23批量导入
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Age-related macular degeneration (AMD) is the most common cause of blindness in older people in developed countries, and risk for this condition may be classified as genetic or environmental, with an interaction between such factors predisposing to this disease. This study investigated the relationship between AMD risk genes, macular pigment optical density (MPOD), which may protect against AMD, and serum concentrations of the macular carotenoids, lutein (L) and zeaxanthin (Z). This was a cross-sectional study of 302 healthy adult subjects. Dietary intake of L and Z was assessed by food frequency questionnaire, and MPOD was measured by customized heterochromatic flicker photometry. We also calculated MPOD Area as the area of MP under the spatial profile curve, to reflect MP across the macula. Serum L and Z were measured by HPLC. Genotyping of tag SNPs in the genes CFH, ARMS2, C3, C2 and BF was undertaken with multiplex polymerase chain reaction (PCR) and primer extension methodology (ABI Snapshot, ABI Warrington UK) on DNA extracted from peripheral blood. The mean ± SD (range) age of the subjects in this study was 48 ± 11 (21-66) years. There was a statistically significant association between CFH genotype and family history of AMD, with subjects having two non-risk CFH haplotypes (n =35), or one non-risk and one protective CFH haplotype (n = 33), being significantly more likely to have a negative family history of AMD (Pearson Chi square: p = 0.001). There was no significant association between the AMD risk genes investigated and either MPOD (One way ANOVA: p > 0.05) or serum concentrations of L or Z (One way ANOVA: p > 0.05, for both). Subjects who were homozygous for risk alleles of both CFH and ARMS2 (n = 4) had significantly lower MPOD at 0.5_ and 1_ retinal eccentricity (Independent samples t test: p
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The neutral complex [HgPh(dmpymt)] 1 (dmpymtH = 4,6-dimethylpyrimidine-2(1H)-thione) reacts with HBF(4) to give the cationic complex [HgPh(dmpymtH)][BF(4)] 2. The X-ray molecular structure of the later revealed a [2+1] coordination sphere about the mercury(II) atom (C-Hg-S and Hg center dot center dot center dot N). In the dinuclear complex [(HgPh)(2)(mu-dtu)] 3 [dtuH(2) = 2,4(1H,3H)-pyrimidinedithione or dithiouracil] the coordination spheres are also [2+1] although dissimilar regarding the Hg center dot center dot center dot N secondary bonds. NMR spectroscopy ((1)H, (13)C and (199)Hg) studies were undertaken in solution and the results discussed in the light of the X-ray structures. (C) 2008 Elsevier B. V. All rights reserved.
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This study aimed to evaluate the potential use of smectite clays for color removal of textile effluents. The experiments were performed by testing exploratory/planning method factorial and fractional factorial where the factors and levels are predetermined. The smectite clays were used originating from gypsum hub of the region Araripe-PE, and the dye used was Reactive Yellow BF-4G 200%. The smectite clay was collected and transported to the Laboratory of Soil Physics of UFRPE, where it held its preparation through air drying, lump breaking and classification in sieve to then submit it to the adsorption process. Upon completion of 22 complete factorial design it was concluded that the values of (96, 96,5 and 95,8%) corresponding to the percentage of of removal for "in-kind", chemically and thermally activated, respectively and adsorbed amounts of (4,80, 4,61 and 4,74 mg/g) for three clays. Showed that the activation processes used did not increase the adsorption capacity of smectite clay. The kinetic data were best fitted to the Freundlich isotherm, with an exponential distribution of active sites and that shows above the Langmuir equation for adsorption of cations and anions by clays. The kinetic model that best adapted to the results was the pseudosecond order model. In the factorial design study 24-1, at concentrations up to 500 mg/L obtains high percentage of color removal (92,37, 90,92 and 93,40%) and adsorbed amount (230,94, 227,31 and 233,50 mg/g) for three clays. The kinetic data fitted well to Langmuir and Freundlich isotherms. The kinetic model that best adapted to the results was the pseudosecond order model
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AIM: To assess the correlation between Wits and AF-BF appraisals with the ANB angle, and verify the influence of the facial type on these appraisals. METHODS: Lateral cephalometric radiographs from 118 untreated individuals were separated into 3 groups according to the facial pattern (brachyfacial, mesofacial, and dolichofacial). The radiographs were digitized and submitted to ANB angle and Wits and AF-BF appraisals on computer software. All radiographs were retraced for intraobserver and interobserver error tests. RESULTS: The Student's t test demonstrated no statistically significant differences on the intraobserver's test (P > .05). There were statistically significant differences in the readings of Wits values of the 3 groups and for AF-BF values in the brachyfacial and mesofacial groups (P <.05). The multiple linear regression tests demonstrated high correlation between ANB and AF-BF for the 3 groups (r2, 0.768). The same result was found for ANB and Wits (r2, 0.624). CONCLUSION: Facial pattern does not have an influence on the correlation between ANB and AF-BF nor between ANB and Wits, but it does influence the measurements of ANB, AF-BF, and Wits.
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We report for the first time the genetic and biological characterization of 10 HIV-1 primary isolates representing CRF28_BF and CRF29_BF together with additional unique BF recombinant forms (URFs) obtained by PBMC cocultivation. Recombination is an important factor promoting the increase in the genetic diversity of HIV-1. Notably, more than 20% of HIV-1 sequences worldwide were recombinants. Several recombinant viruses were reported in Brazil, and six circulating recombinant forms (CRFs) have been identified (CRF28_BF, CRF29_BF, CRF31_BC, CRF39_BF, CRF40_BF, and CRF46_BF). CRF28_BF and CRF29_BF were found to infect almost 30% of the patients in Sao Paulo State. The near full-length genomes of these 10 primary isolates were amplified by nested PCR in three overlapping segments, purified, and sequenced. Three samples were related to CRF28_BF, three to CRF29_BF, and four were unique recombinant forms (URFs), as determined by their breakpoint profile determined with the jpHMM program. Additionally, the coreceptor usage of these isolates was investigated in vitro using GHOST assays, which revealed three dual-tropic (X4/R5) viruses, four lymphotropic (X4) viruses, and three macrophage-tropic (R5) viruses with different V3-loop motifs, which challenges the notion that GWGR-carrying viruses are macrophage-tropic only. In sum, we report a much-anticipated well-characterized panel of viruses representing CRF28_BF, CRF29_BF, and URFs from Sao Paulo State, Brazil.
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Although some studies have shown diversity in HIV integrase (IN) genes, none has focused particularly on the gene evolving in epidemics in the context of recombination. The IN gene in 157 HIV-1 integrase inhibitor-naive patients from the Sao Paulo State, Brazil, were sequenced tallying 128 of subtype B (23 of which were found in non-B genomes), 17 of subtype F (8 of which were found in recombinant genomes), 11 integrases were BF recombinants, and 1 from subtype C. Crucially, we found that 4 BF recombinant viruses shared a recurrent recombination breakpoint region between positions 4900 and 4924 (relative to the HXB2) that includes 2 gRNA loops, where the RT may stutter. Since these recombinants had independent phylogenetic origin, we argue that these results suggest a possible recombination hotspot not observed so far in BF CRF in particular, or in any other HIV-1 CRF in general. Additionally, 40% of the drug-naive and 45% of the drug-treated patients had at least 1 raltegravir (RAL) or elvitegravir (EVG) resistance-associated amino acid change, but no major resistance mutations were found, in line with other studies. Importantly, V151I was the most common minor resistance mutation among B, F and BF IN genes. Most codon sites of the IN genes had higher rates of synonymous substitutions (dS) indicative of a strong negative selection. Nevertheless, several codon sites mainly in the subtype B were found under positive selection. Consequently, we observed a higher genetic diversity in the B portions of the mosaics, possibly due to the more recent introduction of subtype F on top of an ongoing subtype B epidemics and a fast spread of subtype F alleles among the B population.
Serial reports on start-up experiments : no. 5. counting losses in BF₃ proportional counter systems.
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"Work performed under Contract No. AT-30-2-Gen-16."
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Complement factor B and C2 are two central serine proteases of the alternative and classical complement pathways, respectively, that serve as the catalytic subunits of the C3 convertase. Research has been completed using a female Japanese medaka fish, (Oryzias latipes), and other teleost and elasmobrach species in order to isolate eDNA clones and perform linkage analysis of the Bf/C2 gene(s). To further analyze the evolution of the complement system in teleosts, different tissues than the ones from previous studies of medaka fish were analyzed for the constitutive gene expression of factor B and C2. Bf/C2 sequences were amplified by reverse transcription-polymerase chain reaction with primers corresponding to the common amino acid sequences shared by mammalian Bf and C2. Agarose gel electrophoresis was used to visualize sample bands and to calculate the concentration of gene expression of the Bf/C2 gene(s) in each tissue. All five tissue types, kidney, liver, muscle, testis, and spleen from a male medaka fish demonstrated Bf/C2 gene(s) expression, confirming that the messages of Bf/C2 gene(s) are distributed throughout the medaka fish. Tissues of the spleen, liver, and kidney contained the highest concentrations of expression of Bf/C2 gene( s ), while tissues of the muscle and testis contained the lowest concentrations. This research also determined that RT-PCR allowed for more sensitive analysis of gene expression than other molecular biology techniques such as Northern blotting analysis.