Presently the gold standard diagnostic technique for rabies is the direct immunofluorescence assay （dFA） which is very expensive and requires a high level of expertise. There is a need for more economical and user f...Presently the gold standard diagnostic technique for rabies is the direct immunofluorescence assay （dFA） which is very expensive and requires a high level of expertise. There is a need for more economical and user friendly tests, particularly for use in developing countries. We have established one such test called the direct rapid immunohistochemical test （dRIT） for diagnosis of rabies using brain tissue. The test is based on capture of rabies nucleoprotein （N） antigen in brain smears using a cocktail of biotinylated monoclonal antibodies specific for the N protein and color development by streptavidin peroxidase-amino ethyl carbazole and counter staining with haematoxollin. The test was done in parallel with standard FAT dFA using 400 brain samples from different animals and humans. The rabies virus N protein appears under fight microscope as reddish brown particles against a light blue background. There was 100 % correlation between the results obtained by the two tests. Also, interpretation of results by dRIT was easier and only required a light microscope. To conclude, this newly developed dRIT technique promises to be a simple, cost effective diagnostic tool for rabies and will have applicability in field conditions prevalent in developing countries.展开更多
Using standard and internationally validated methods,86 anthropologic characteristics were determined in 650 male(305 from urban areas and 345 from rural areas) and 704 female(331 from urban areas,373 from rural areas...Using standard and internationally validated methods,86 anthropologic characteristics were determined in 650 male(305 from urban areas and 345 from rural areas) and 704 female(331 from urban areas,373 from rural areas) Chinese Hakka adults living in Guangdong and Jiangxi.The data were used to calculate 24 anthropologic indices,which were analyzed statistically.The physical characteristics of Hakka subjects were analyzed and compared with reference ethnic data.There were four main findings of this study.First,a small proportion of Hakka adults had an eye fold on the upper eyelid,but a large proportion had a mongoloid fold.The eye slits were narrow in most adults,had a medium nasal root height and straight bridges,and most of the external angles were prominent.The nasal base was upturned in most men.The distributions of the three types of nasal base in women were similar.The proportions of subjects with middle and high alae nasi heights were high and similar.Males with a maximum nostril diameter were mostly classified as transverse and oblique,while many women were classified as transverse and had relatively wide alae nasi.The round lobe type was the most common.Upper lip skin height was mostly classified as medium.Lips were classified as thin.The hair was black,eyes were brown,and the skin was yellowish.Second,the head length was long in male Hakka.The minimum frontal breadth,face breadth,lip height,and interocular breadth were similar to those of North-Asian populations.Meanwhile,head breadth,morphological facial height,nose breadth,mouth breadth,and nose height were similar to those of South-Asian populations.Head length was long in female Hakka.The minimum frontal breadth,face breadth,lip height,and interocular breadth were similar to those of North-Asian populations.Head breadth,nose breadth,and mouth breadth were similar to those of South-Asian populations.Third,the stature of male and female Hakka in urban and rural areas was classified as medium.The proportions of male and female Hakka classified as mesocephaly(length-breadth index of the head),hypsicephalic type,metriocephalic type(breadth-height index of the head) mesorrhiny,long trunk,subbrachyskelic type,broad shoulder breadth,and narrow distance between iliac crests were higher than those of other types.Finally,principal component analyses showed that the physical characteristics of Hakka were between those of South-Asian and North-Asian ethnic populations,but were generally closer to those of North-Asian populations in China.展开更多
Since the creation of intelligent creatures,we are no longer the puppets of the creator.For thousands of years,people have been thinking about the nature and the future of ourselves,and reconstruction of the process o...Since the creation of intelligent creatures,we are no longer the puppets of the creator.For thousands of years,people have been thinking about the nature and the future of ourselves,and reconstruction of the process of life has become the ultimate dream for us.In 1951,William Harvey,a British scientist,elaborated the theory of the structure and function of embryos for the first time in his book'the reproduction of animals',which established the foundation for people to explore the process and the mechanism of embryonic development.展开更多
Editor＇s comments The human mutation rate how often new changes appear in the DNA--is fundamental to understanding many aspects of medical genetics and human evolutionary genetics. But it is low, and has therefore b...Editor＇s comments The human mutation rate how often new changes appear in the DNA--is fundamental to understanding many aspects of medical genetics and human evolutionary genetics. But it is low, and has therefore been difficult to measure. In the past, scientists could only estimate it approximately, either by observing how often mutant phenotypes appeared, or by comparison of humans and closely related species, such as chimpanzee, where many mutations could accumulate but the time period was uncertain. Now, a new study supported by the NSFC in China and The Royal Society in the UK reports the first direct measurement of the human mutation rate at the individual letters （ nucleotides or bases） of DNA. This was possible because new （ next ）-generation sequencing technology is much more powerful than the methods available previously. The work was published in the lead- ing journal Currerzt Biology on 15th September 2009. The results were reported in the news by Nature, Science and the BBC , as well as in more than 20 Chinese newspapers and radio stations after the work first appeared online on 27th August. It was also one of the research highlights in Nature on 3rd September, which commented ＂ This direct measurement of the human mutation rate should help researchers to refine evolutionary dating and better understand the source of genetic disease＇. From the work, researchers could estimate that everyone has around 200 new mutations in their genome ; as the authors said, ＂we are all mutants＂. The ability to reliably measure rates of DNA mutation means we can begin to ask how mutation rates vary between different regions of the genome and perhaps also between different individuals.展开更多
文摘Presently the gold standard diagnostic technique for rabies is the direct immunofluorescence assay （dFA） which is very expensive and requires a high level of expertise. There is a need for more economical and user friendly tests, particularly for use in developing countries. We have established one such test called the direct rapid immunohistochemical test （dRIT） for diagnosis of rabies using brain tissue. The test is based on capture of rabies nucleoprotein （N） antigen in brain smears using a cocktail of biotinylated monoclonal antibodies specific for the N protein and color development by streptavidin peroxidase-amino ethyl carbazole and counter staining with haematoxollin. The test was done in parallel with standard FAT dFA using 400 brain samples from different animals and humans. The rabies virus N protein appears under fight microscope as reddish brown particles against a light blue background. There was 100 % correlation between the results obtained by the two tests. Also, interpretation of results by dRIT was easier and only required a light microscope. To conclude, this newly developed dRIT technique promises to be a simple, cost effective diagnostic tool for rabies and will have applicability in field conditions prevalent in developing countries.
基金supported by the National Natural Science Foundation of China (30830062)Jiaying University in GuangdongGan County Board of Education,Jiangxi for their financial support
文摘Using standard and internationally validated methods,86 anthropologic characteristics were determined in 650 male(305 from urban areas and 345 from rural areas) and 704 female(331 from urban areas,373 from rural areas) Chinese Hakka adults living in Guangdong and Jiangxi.The data were used to calculate 24 anthropologic indices,which were analyzed statistically.The physical characteristics of Hakka subjects were analyzed and compared with reference ethnic data.There were four main findings of this study.First,a small proportion of Hakka adults had an eye fold on the upper eyelid,but a large proportion had a mongoloid fold.The eye slits were narrow in most adults,had a medium nasal root height and straight bridges,and most of the external angles were prominent.The nasal base was upturned in most men.The distributions of the three types of nasal base in women were similar.The proportions of subjects with middle and high alae nasi heights were high and similar.Males with a maximum nostril diameter were mostly classified as transverse and oblique,while many women were classified as transverse and had relatively wide alae nasi.The round lobe type was the most common.Upper lip skin height was mostly classified as medium.Lips were classified as thin.The hair was black,eyes were brown,and the skin was yellowish.Second,the head length was long in male Hakka.The minimum frontal breadth,face breadth,lip height,and interocular breadth were similar to those of North-Asian populations.Meanwhile,head breadth,morphological facial height,nose breadth,mouth breadth,and nose height were similar to those of South-Asian populations.Head length was long in female Hakka.The minimum frontal breadth,face breadth,lip height,and interocular breadth were similar to those of North-Asian populations.Head breadth,nose breadth,and mouth breadth were similar to those of South-Asian populations.Third,the stature of male and female Hakka in urban and rural areas was classified as medium.The proportions of male and female Hakka classified as mesocephaly(length-breadth index of the head),hypsicephalic type,metriocephalic type(breadth-height index of the head) mesorrhiny,long trunk,subbrachyskelic type,broad shoulder breadth,and narrow distance between iliac crests were higher than those of other types.Finally,principal component analyses showed that the physical characteristics of Hakka were between those of South-Asian and North-Asian ethnic populations,but were generally closer to those of North-Asian populations in China.
基金supported by the National Nature Science of China(3147127791649202)National key R&D program of China(2016YFA0500901)
文摘Since the creation of intelligent creatures,we are no longer the puppets of the creator.For thousands of years,people have been thinking about the nature and the future of ourselves,and reconstruction of the process of life has become the ultimate dream for us.In 1951,William Harvey,a British scientist,elaborated the theory of the structure and function of embryos for the first time in his book'the reproduction of animals',which established the foundation for people to explore the process and the mechanism of embryonic development.
文摘Editor＇s comments The human mutation rate how often new changes appear in the DNA--is fundamental to understanding many aspects of medical genetics and human evolutionary genetics. But it is low, and has therefore been difficult to measure. In the past, scientists could only estimate it approximately, either by observing how often mutant phenotypes appeared, or by comparison of humans and closely related species, such as chimpanzee, where many mutations could accumulate but the time period was uncertain. Now, a new study supported by the NSFC in China and The Royal Society in the UK reports the first direct measurement of the human mutation rate at the individual letters （ nucleotides or bases） of DNA. This was possible because new （ next ）-generation sequencing technology is much more powerful than the methods available previously. The work was published in the lead- ing journal Currerzt Biology on 15th September 2009. The results were reported in the news by Nature, Science and the BBC , as well as in more than 20 Chinese newspapers and radio stations after the work first appeared online on 27th August. It was also one of the research highlights in Nature on 3rd September, which commented ＂ This direct measurement of the human mutation rate should help researchers to refine evolutionary dating and better understand the source of genetic disease＇. From the work, researchers could estimate that everyone has around 200 new mutations in their genome ; as the authors said, ＂we are all mutants＂. The ability to reliably measure rates of DNA mutation means we can begin to ask how mutation rates vary between different regions of the genome and perhaps also between different individuals.
