LEF1/TCFs are high mobility group box-containing transcriptional factors mediating canonical Wnt/β-catenin signaling during early embryogenesis and tumorigenesis. β-Catenin forms a complex with LEF 1/TCFs and transa...LEF1/TCFs are high mobility group box-containing transcriptional factors mediating canonical Wnt/β-catenin signaling during early embryogenesis and tumorigenesis. β-Catenin forms a complex with LEF 1/TCFs and transactivates LEF1/TCF-mediated transcriptions during dorsalization. Although LEF-mediated transcription is also implicated in ventralization, the underlying molecular mechanism is not well understood. Using the vertebrate Xenopus laevis model system, we found that Xom, which is a ventralizing homeobox protein with dual roles of transcriptional activation and repression, forms a complex with LEF 1/TCF through its homeodomain and transactivates LEF 1/TCF-mediated transcription through its N-terminal transactivation domain （TAD）. Our data show that Xom lacking the N-terminal TAD fails to transactivate ventral genes, such as BMP4 and Xom itself, but retains the ability to suppress transcriptional activation of dorsal gene promoters, such as the Goosecoid promoter, indicating that transactivation and repression are separable functions of Xom. It has been postulated that Xom forms a positive re-enforcement loop with BMP4 to promote ventral- ization and to suppress dorsal gene expression. Consistent with an essential role of Xom transactivation of LEF1/TCFs during early embryogenesis, we found that expression of the dominant-negative Xom mutant that lacks the TAD fails to re-enforce the ventral signaling of BMP4 and causes a catastrophic effect during gastrulation. Our data suggest that the functional interaction of Xom and LEF 1/TCF-factors is essential for ventral cell fate determination and that LEF 1/TCF factors may function as a point of convergence to mediate the combined signaling of Wnt/β-catenin and BMP4/Xom pathways during early embryogenesis.展开更多
The four-seasonal movement is the general movement of the universe. Galaxies, living beings, society, man-made worlds and all substances have or take part in the four-seasonal movement. There are transverse four-seaso...The four-seasonal movement is the general movement of the universe. Galaxies, living beings, society, man-made worlds and all substances have or take part in the four-seasonal movement. There are transverse four-seasonal movement and longitudinal four-seasonal movement. The former is the breathing movement. All substances have the function of breathing. Breathing involves living beings, celestial bodies, society and man-made systems and living beings of different levels have different ways of breathing. The longitudinal four-seasonal movement of living beings is controlled by genes. The four-seasonal movement is confined. Life originates in seeds and seeds are generated in the four-seasonal movement. Thoughts, ideas, designs and methods are the seeds of celestial bodies, society and man-made worlds. Just like living beings, galaxies, and society also have reproductive function. Reproduction has three major means： self-generation, generation by augmentation and generation by transformation. The reproduction of living beings is self-generation while the reproduction of the solar system and other galaxies is generation by augmentation. Man-made objects, society and galaxies are formed with automatic organization of thoughts, thus called generation by transformation. The solar system and the earth have reproduction function. Living beings began with the combined action of the earth, the solar system and the universe. Life forms of the universe include dominant life and recessive life. Different forms of life transform continuously.展开更多
Ion channels are membrane proteins that are found in a number of viruses and which are of crucial physiological importance in the viral life cycle. They have one common feature in that their action mode involves a cha...Ion channels are membrane proteins that are found in a number of viruses and which are of crucial physiological importance in the viral life cycle. They have one common feature in that their action mode involves a change of electrochemical or proton gradient across the bilayer lipid membrane which modulates viral or cellular activity. We will discuss a group of viral channel proteins that belong to the viroproin family, and which participate in a number of viral functions including promoting the release of viral particles from cells. Blocking these channel-forming proteins may be ＂lethal＂, which can be a suitable and potential therapeutic strategy. In this review we discuss seven ion channels of viruses which can lead serious infections in human beings： M2 of influenza A, NB and BM2 of influenza B, CM2 of influenza C, Vpu of HIV-1, p7 of HCV and 2B of picomaviruses.展开更多
Effects of four commercial ornamentals on the development, survivorship and reproduction of the whitefly B biotype Bemisia tabaci (Gennadius) were studied in the laboratory (temperature 26 ±1℃; relative humidity...Effects of four commercial ornamentals on the development, survivorship and reproduction of the whitefly B biotype Bemisia tabaci (Gennadius) were studied in the laboratory (temperature 26 ±1℃; relative humidity 75%-90%; L: D 14:10). The total survivorship from egg to adult on hibiscus (Hibiscus rosa-sinensis L.), poinsettia (Euphorbia pulcherrima Will), cottonrose hibiscus (Hibiscus mutabilis L.) and variegated leafcroton (Codiaeum variegatum ‘Aucubaefolium') were 33.69%, 40.55%, 79.11%, and 29.39%,respectively. The developmental periods from egg to adult varied from 23.12 days on cottonrose hibiscus to 32.13 days on hibiscus. The average longevity of adult females ranged from 6.87 days on variegated leafcroton to 21.07 days on poinsettia. The average numbers of eggs laid per female were 9.20, 25.13, 54.45, and 26.79 on the above respective hosts. The intrinsic rates of natural increase (rm) for B biotype B. tabaci on cottonrose hibiscus was the highest. Based on life table analyses of whitefly populations, cottonrose hibiscus was the most suitable host for B biotype B. tabaci in this study.展开更多
Purpose： Emergency department resuscitative thoracotomy is an intervention of last resort for the acutely dying victim of trauma. In light of improvements in pre-hospital emergency systems, improved operative strateg...Purpose： Emergency department resuscitative thoracotomy is an intervention of last resort for the acutely dying victim of trauma. In light of improvements in pre-hospital emergency systems, improved operative strategies for survival such as damage control and improvements in critical care medicine, the most extreme of resuscitation efforts should be re-evaluated for the potential survivor, with success properly defined as the return of vital signs which allow transport of the patient to the operating room. Methods： A retrospective review of all patients at a suburban level I trauma center who underwent emergency department resuscitative thoracotomy as an adjunct to the resuscitation efforts normally delivered in the trauma receiving area over a 22 year period was performed. Survival of emergency department resuscitative thoracotomy was defined as restoration of vital signs and transport out of the trauma resuscitation area to the operating room. Results： Sixty-eight patients were identified, of whom 27 survived the emergency department resusci- tative thoracotomy and were transported to the operating room. Review of pre-hospital and initial hospital data between these potential long term survivors and those who died in the emergency department failed to demonstrate trends which were predictive of survival of emergency department resuscitative thoracotomy. The only subgroup which failed to respond to emergency department resuscitative thoracotomy was patients without signs of life at the scene who arrived to the treatment facility without signs of life. Conclusion： The patient population of the ＂potential survivor＂ has been expanded due to advances in critical care practices, technology, and surgical technique and every opportunity for survival should be provided at the outset. Emergency department resuscitative thoracotomy is warranted for any patient with thoracic or subdiaphragmatic trauma who presents in extremis with a history of signs of life at the scene or organized cardiac activity upon arrival. Patients who have no evidence of signs of life at the scene and have no organized cardiac activity upon arrival should be pronounced.展开更多
文摘LEF1/TCFs are high mobility group box-containing transcriptional factors mediating canonical Wnt/β-catenin signaling during early embryogenesis and tumorigenesis. β-Catenin forms a complex with LEF 1/TCFs and transactivates LEF1/TCF-mediated transcriptions during dorsalization. Although LEF-mediated transcription is also implicated in ventralization, the underlying molecular mechanism is not well understood. Using the vertebrate Xenopus laevis model system, we found that Xom, which is a ventralizing homeobox protein with dual roles of transcriptional activation and repression, forms a complex with LEF 1/TCF through its homeodomain and transactivates LEF 1/TCF-mediated transcription through its N-terminal transactivation domain （TAD）. Our data show that Xom lacking the N-terminal TAD fails to transactivate ventral genes, such as BMP4 and Xom itself, but retains the ability to suppress transcriptional activation of dorsal gene promoters, such as the Goosecoid promoter, indicating that transactivation and repression are separable functions of Xom. It has been postulated that Xom forms a positive re-enforcement loop with BMP4 to promote ventral- ization and to suppress dorsal gene expression. Consistent with an essential role of Xom transactivation of LEF1/TCFs during early embryogenesis, we found that expression of the dominant-negative Xom mutant that lacks the TAD fails to re-enforce the ventral signaling of BMP4 and causes a catastrophic effect during gastrulation. Our data suggest that the functional interaction of Xom and LEF 1/TCF-factors is essential for ventral cell fate determination and that LEF 1/TCF factors may function as a point of convergence to mediate the combined signaling of Wnt/β-catenin and BMP4/Xom pathways during early embryogenesis.
文摘The four-seasonal movement is the general movement of the universe. Galaxies, living beings, society, man-made worlds and all substances have or take part in the four-seasonal movement. There are transverse four-seasonal movement and longitudinal four-seasonal movement. The former is the breathing movement. All substances have the function of breathing. Breathing involves living beings, celestial bodies, society and man-made systems and living beings of different levels have different ways of breathing. The longitudinal four-seasonal movement of living beings is controlled by genes. The four-seasonal movement is confined. Life originates in seeds and seeds are generated in the four-seasonal movement. Thoughts, ideas, designs and methods are the seeds of celestial bodies, society and man-made worlds. Just like living beings, galaxies, and society also have reproductive function. Reproduction has three major means： self-generation, generation by augmentation and generation by transformation. The reproduction of living beings is self-generation while the reproduction of the solar system and other galaxies is generation by augmentation. Man-made objects, society and galaxies are formed with automatic organization of thoughts, thus called generation by transformation. The solar system and the earth have reproduction function. Living beings began with the combined action of the earth, the solar system and the universe. Life forms of the universe include dominant life and recessive life. Different forms of life transform continuously.
文摘Ion channels are membrane proteins that are found in a number of viruses and which are of crucial physiological importance in the viral life cycle. They have one common feature in that their action mode involves a change of electrochemical or proton gradient across the bilayer lipid membrane which modulates viral or cellular activity. We will discuss a group of viral channel proteins that belong to the viroproin family, and which participate in a number of viral functions including promoting the release of viral particles from cells. Blocking these channel-forming proteins may be ＂lethal＂, which can be a suitable and potential therapeutic strategy. In this review we discuss seven ion channels of viruses which can lead serious infections in human beings： M2 of influenza A, NB and BM2 of influenza B, CM2 of influenza C, Vpu of HIV-1, p7 of HCV and 2B of picomaviruses.
文摘Effects of four commercial ornamentals on the development, survivorship and reproduction of the whitefly B biotype Bemisia tabaci (Gennadius) were studied in the laboratory (temperature 26 ±1℃; relative humidity 75%-90%; L: D 14:10). The total survivorship from egg to adult on hibiscus (Hibiscus rosa-sinensis L.), poinsettia (Euphorbia pulcherrima Will), cottonrose hibiscus (Hibiscus mutabilis L.) and variegated leafcroton (Codiaeum variegatum ‘Aucubaefolium') were 33.69%, 40.55%, 79.11%, and 29.39%,respectively. The developmental periods from egg to adult varied from 23.12 days on cottonrose hibiscus to 32.13 days on hibiscus. The average longevity of adult females ranged from 6.87 days on variegated leafcroton to 21.07 days on poinsettia. The average numbers of eggs laid per female were 9.20, 25.13, 54.45, and 26.79 on the above respective hosts. The intrinsic rates of natural increase (rm) for B biotype B. tabaci on cottonrose hibiscus was the highest. Based on life table analyses of whitefly populations, cottonrose hibiscus was the most suitable host for B biotype B. tabaci in this study.
文摘Purpose： Emergency department resuscitative thoracotomy is an intervention of last resort for the acutely dying victim of trauma. In light of improvements in pre-hospital emergency systems, improved operative strategies for survival such as damage control and improvements in critical care medicine, the most extreme of resuscitation efforts should be re-evaluated for the potential survivor, with success properly defined as the return of vital signs which allow transport of the patient to the operating room. Methods： A retrospective review of all patients at a suburban level I trauma center who underwent emergency department resuscitative thoracotomy as an adjunct to the resuscitation efforts normally delivered in the trauma receiving area over a 22 year period was performed. Survival of emergency department resuscitative thoracotomy was defined as restoration of vital signs and transport out of the trauma resuscitation area to the operating room. Results： Sixty-eight patients were identified, of whom 27 survived the emergency department resusci- tative thoracotomy and were transported to the operating room. Review of pre-hospital and initial hospital data between these potential long term survivors and those who died in the emergency department failed to demonstrate trends which were predictive of survival of emergency department resuscitative thoracotomy. The only subgroup which failed to respond to emergency department resuscitative thoracotomy was patients without signs of life at the scene who arrived to the treatment facility without signs of life. Conclusion： The patient population of the ＂potential survivor＂ has been expanded due to advances in critical care practices, technology, and surgical technique and every opportunity for survival should be provided at the outset. Emergency department resuscitative thoracotomy is warranted for any patient with thoracic or subdiaphragmatic trauma who presents in extremis with a history of signs of life at the scene or organized cardiac activity upon arrival. Patients who have no evidence of signs of life at the scene and have no organized cardiac activity upon arrival should be pronounced.
