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1.
Viruses ; 15(7)2023 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-37515122

RESUMEN

As one of the most important avian immunosuppressive and neoplastic diseases, Marek's disease (MD), caused by oncogenic Marek's disease virus (MDV), has caused huge economic losses worldwide over the past five decades. In recent years, MD outbreaks have occurred frequently in MD-vaccinated chicken flocks, but the key pathogenic determinants and influencing factors remain unclear. Herein, we analyzed the pathogenicity of seven newly isolated MDV strains from tumor-bearing chickens in China and found that all of them were pathogenic to chicken hosts, among which four MDV isolates, SDCW01, HNXZ05, HNSQ05 and HNSQ01, were considered to be hypervirulent MDV (HV-MDV) strains. At 73 days of the virus infection experiment, the cumulative incidences of MD were 100%, 93.3%, 90% and 100%, with mortalities of 83.3%, 73.3%, 60% and 86.7%, respectively, for the four viruses. The gross occurrences of tumors were 50%, 33.3%, 30% and 63.3%, respectively, accompanied by significant hepatosplenomegaly and serious atrophy of the immune organs. Furthermore, the immune protection effects of four commercial MD vaccines against SDCW01, CVI988, HVT, CVI988+HVT, and 814 were explored. Unexpectedly, during the 67 days of post-virus challenge, the protection indices (PIs) of these four MD vaccines were only 46.2%, 38.5%, 50%, and 28%, respectively, and the birds that received the monovalent CVI988 or HVT still developed tumors with cumulative incidences of 7.7% and 11.5%, respectively. To our knowledge, this is the first demonstration of the simultaneous comparison of the immune protection efficacy of multiple commercial MD vaccines with different vaccine strains. Our study revealed that the HV-MDV variants circulating in China could significantly break through the immune protection of the classical MD vaccines currently widely used. For future work, there is an urgent need to develop novel, more effective MD vaccines for tackling the new challenge of emerging HV-MDV strains or variants for the sustainable control of MD.


Asunto(s)
Herpesvirus Gallináceo 2 , Vacunas contra la Enfermedad de Marek , Enfermedad de Marek , Neoplasias , Animales , Pollos , Herpesvirus Gallináceo 2/genética , Vacunas contra la Enfermedad de Marek/genética
2.
Zhonghua Nan Ke Xue ; 19(4): 321-3, 2013 Apr.
Artículo en Chino | MEDLINE | ID: mdl-23678710

RESUMEN

OBJECTIVE: To assess the long-term effect and safety of non-occlusive intra-vas device (IVD) for male contraception in comparison with no-scalpel vasectomy (NSV). METHODS: We conducted a follow-up investigation on 100 males who had received IVD and another 50 who had undergone NSV 6 years before. We compared the rates of sperm absence and complications between the two groups. RESULTS: Follow-up visits were successfully performed on 95 males (95%) of the IVD group and 44 (88%) of the NSV group. Pregnancy was not found in any of the cases. Spermatozoa (> or = 5 x 10(6)/ml) were not detected in 87 cases (91.58%) in the IVD group and in 44 cases (95.45%) in the NSV group, with no significant differences between the two groups (P > 0.05). The rate of postoperative complications in the IVD group (11.58%) showed no significant difference from that of the NSV group (4.55%) (P > 0.05). CONCLUSION: IVD is as effective and safe as NSV for male contraception.


Asunto(s)
Anticoncepción/métodos , Conducto Deferente , Adulto , Estudios de Seguimiento , Humanos , Masculino , Vasectomía
3.
J Am Chem Soc ; 133(30): 11632-40, 2011 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-21707062

RESUMEN

An operationally simple approach for the preparation of a new class of bifunctional Au nanoparticle-acid catalysts has been developed. In situ reduction of Au(3+) with HS-functionalized periodic mesoporous organosilicas (PMOs) creates robust, fine Au nanoparticles and concomitantly produces a sulfonic acid moiety strongly bonded to PMOs. Characterizations of the nanostructures reveal that Au nanoparticles are formed with uniformed, narrow size distribution around 1-2 nm, which is very critical for essential catalytic activities. Moreover, the Au nanoparticles are mainly attached onto the pore surface rather than onto the outer surface with ordered mesoporous channels, allowing for maximal exposure to reaction substrates while minimizing Au nanoparticle leaching. Their higher S(BET), V(P), and D(P) than either the Au-HS-PMO(Et) or the Au/SO(3)H-PMO(Et) render the catalyst with comparably even higher catalytic efficiency than its homogeneous counterparts. Furthermore, the unique amphiphilic compartment of the Au-HS/SO(3)H-PMO(Et) nanostructures enables organic reactions to proceed efficiently in a pure aqueous solution without using any organic solvents or even without water. As demonstrated experimentally, remarkably, the unique bifunctional Au-HS/SO(3)H-PMO(Et) catalyst displays higher efficiencies in promoting water-medium alkyne hydration, intramolecular hydroamination, styrene oxidation, and three-component coupling reactions and even the solvent-free alkyne hydration process than its homogeneous catalysts. The robust catalyst can be easily recycled and used repetitively at least 10 times without loss of catalytic efficiency. These features render the catalyst particularly attractive in the practice of organic synthesis in an environmentally friendly manner.


Asunto(s)
Oro/química , Sulfuro de Hidrógeno/química , Nanopartículas del Metal/química , Compuestos de Organosilicio/química , Sulfatos/química , Agua/química , Catálisis , Tamaño de la Partícula , Porosidad , Propiedades de Superficie
4.
Comput Biol Med ; 40(7): 671-9, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20591423

RESUMEN

The oxidation of adenine in phosphate buffer solution is investigated using square-wave voltammetry and in situ UV spectroelectrochemistry. The geometry of adenine and the derivatives optimized at DFTB3LYP-6-31G (d, p)-PCM level is in agreement with the crystal structure, and the imitated UV spectra of adenine and the product at electrode are consistent with the in situ UV spectra. The relationship between the electrochemical property and the molecular structure is also discussed. The experimental and theoretical results show that the adenine oxidation origins from the neutral adenine.


Asunto(s)
Adenina/química , Técnicas Electroquímicas , Fosfatos/química , Espectrofotometría Ultravioleta , Tampones (Química) , Distribución Normal , Oxidación-Reducción
5.
Beijing Da Xue Xue Bao Yi Xue Ban ; 42(3): 308-13, 2010 Jun 18.
Artículo en Chino | MEDLINE | ID: mdl-20559407

RESUMEN

OBJECTIVE: To understand the spectrum of diseases and epidemiological characteristics of outpatients at Entric Disease Clinic, with a focus on analysis of the distribution of infectious diarrheal diseases in different populations and to explore disease control strategies on Enteric Infectious Diseases for focal groups. METHODS: A census on outpatients at Entric Disease Clinics was conducted in two class Three comprehensive hospitals in Beijing from April 1 to October 31, 2009 based on a descriptive study using diarrhea-syndrome surveillance system set in the two clinics, thus to depict the spectrum of diseases and epidemiological characteristics of outpatients, and analyze the proportion of infectious diarrhea in diarrheal diseases specifically and the rate changes of infectious diarrhea in different months, age groups and occupational groups. RESULTS: Diseases are varied at the two enteric diseases clinics among the patients and there are mainly 10 kinds of diseases, "non-infectious diarrhea" accounted for the highest percentage (77.4%), followed by "unspecified diarrhea" (11.7%), and infectious diarrhea accounted for the least proportion(8.7%)."Gastroenteritis and enteritis" are the most frequently diagnosed cases among all the diseases, was a total of 7 565 cases, accounting for 70.2%. The volume of visits reached its top during summer and autumn(July to September), and the mean volume of visits in this period is (60.78+/-16.85) cases/day. The volume of visits has an obvious seasonal trend, and visits during July and August are the most frequent (41.82% altogether). Patients with "infectious diarrhea" had a highest ratio(5.3%) in May and lowest (1.1%) in October while patients with "bacillary dysentery" accounted for a highest ratio(8.2%) in September and lowest(3.8%) in April. Outpatients are mainly from Beijing city(61.9%), in which young and middle-aged people accounted for 73.9% in total, and student is the main occupation (28.8%). The distributions of diarrheal diseases are the same in different age groups but differ from different occupational groups. Infectious diarrhea accounted for a highest proportion(9.2%) in 18-to-44-year-old age group when using age grouping, and a highest proportion(15.2%) in restaurant service personnel when using occupation grouping. CONCLUSION: The volume of outpatients attended at general hospitals is overwhelming especially in July and August, and the major type is "non-infectious diseases", which indicates an arduous task on prevention and control of Enteric Infectious Diseases. Infectious diarrhea took up a certain amount, but the rate is not that high, which indicates possible missing diagnosis of patients with infectious diseases.Our focal groups would be young and middle-aged people and students in the city. Therefore, the need to extend the consultation hours is urgent. Meanwhile, for the main goal of surveillance and early warning on Enteric Infectious Diseases, all aspects of construction of Enteric Disease Clinic should be strengthened, such as enhance laboratory tests on pathogens, improve diagnosis level of physicians and etc.


Asunto(s)
Diarrea/epidemiología , Disentería Bacilar/epidemiología , Disentería/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , China/epidemiología , Femenino , Hospitales , Humanos , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Prevalencia , Estaciones del Año , Adulto Joven
6.
Biomed Environ Sci ; 21(6): 485-91, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19263804

RESUMEN

OBJECTIVE: To study the specific amino acid variation in Nef that may be related to disease progression after infection with HIV-1 subtype B, a predominant strain circulating in China, and to determine whether changes in Nef secondary structure may influence different stages of AIDS development based on the concept that the Nef gene of HIV infection dramatically alter the severity of viral infection and virus replication and disease progression, and that long-term non-progressors (LTNP) of HIV infection are commonly associated with either a deletion of the Nef gene or the defective Nef alleles. METHODS: The study subjects were divided into LTNP1(n=14), LTNP2 (n=16) and slow progressor (SP, n=19) groups for mutational analysis of the Nef sequence. The data were obtained by using Bioedit, MEGA, Anthewin and SAS software. RESULTS: Residues in Nef TA(48/49) and K151 occurred more frequently in the LTNP group while AA(48/49) was more frequently observed in the SP group. Of the differences observed in the secondary structure comparison using Nef consensus sequences of these three groups, one was roughly corresponding to the Nef(48/49) mutation site. CONCLUSION: TA(48/49), K(151), and AA(48/49) in the Nef gene might be associated with the different stages of HIV infection, and there may be a link between the Nef secondary structure and the progression of HIV-1 infection.


Asunto(s)
Donantes de Sangre , Progresión de la Enfermedad , Productos del Gen nef/genética , Infecciones por VIH/virología , Sobrevivientes de VIH a Largo Plazo , VIH-1/clasificación , VIH-1/genética , Secuencia de Aminoácidos , Secuencia de Bases , Recuento de Linfocito CD4 , China/epidemiología , Infecciones por VIH/epidemiología , Humanos , Datos de Secuencia Molecular , Mutación/genética , Factores de Tiempo
7.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 10): o1998, 2008 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-21201196

RESUMEN

In the mol-ecule of the title compound, C(9)H(7)NOS(2), the heterocycle and the phenyl ring are oriented at a dihedral angle of 72.3 (1)°. Adjacent mol-ecules are connected through C-H⋯O inter-actions.

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