Disruption of cell proliferation and apoptosis balance in the testes of crossbred cattle-yaks affects spermatogenic cell fate and sterility.

The balance between proliferation, differentiation and apoptosis is well-coordinated in spermatogenesis for the timely production of appropriate numbers of sperm in animals. Disruption or decrease in sperm production is due to many conditions, including changes in testicular cell fate balance. Interspecies hybridization of domestic yaks and cattle results in sterility in males because of spermatogenic arrest; however, the underlying mechanisms involved in sterility are still unclear. In the present study, we investigated the proliferation and apoptosis status during the development of yaks and crossbred cattle-yaks using immunohistochemistry of proliferating cell nuclear antigen and terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assays. Testicular tissues from yaks (immature: 1 year old, mature: 2-3 years old) and backcrossed hybrids (2 year old) were collected and used to investigate the expression of each parameter in testicular cells. During the maturation of yak testes, proliferation and apoptosis became active only in spermatogenic cells, and not in other somatic cells, such as Sertoli cells, myoid cells and Leydig cells. Furthermore, hybrid cattle-yak testes maintained proliferation ability but less apoptotic ability in spermatogenic cells when compared to yaks of the same age, suggesting that normal spermatogenic cell fate control is disrupted by changes in the balance between proliferation and apoptosis. In addition, Leydig cell proliferation rate was higher than apoptosis rate in the cattle-yak testes, indicating an increased number of Leydig cells, which may affect spermatogenesis through changes in steroidogenesis. Although epigenetic changes may be involved in cattle-yak testes, further studies are needed to clarify the modulation of proliferation and apoptosis to elucidate the mechanisms of infertility in hybrid cattle-yak males.

Enantioselective Epoxidation of 2,3-Disubstituted Naphthoquinones by a Side Chain Truncated Guanidine-Urea Bifunctional Organocatalyst.

An organocatalytic enantioselective epoxidation of 2,3-disubstituted naphthoquinones with tert-butyl hydroperoxide as an oxidant was developed using a guanidine-urea bifunctional catalyst lacking C2 symmetry, which was designed based upon the insights obtained from the DFT calculation model for our previous C2 symmetric catalyst. The present organocatalytic reaction provides access to a variety of optically active naphthoquinone epoxides bearing aryl and methyl substituents at C2 and C3 in high yields with high enantioselectivities (up to 97:3 er).

The Ability for Basic Movement Scale II Can Predict Functional Outcome and Discharge Destination in Stroke Patients.

OBJECTIVES: This study aims to identify whether the Ability for Basic Movement Scale II (ABMS II) at admission would predict the functional status and discharge destination in convalescent stroke patients. METHODS: Ninety-four stroke patients admitted to convalescent rehabilitation ward were investigated. Their functions were evaluated by the ABMS II and Functional Independence Measure (FIM) at admission, FIM and Functional Ambulation Category at discharge. Furthermore, the age, gender, diagnosis, lesion side, onset type, interval between onset and convalescent admission, length of stay (LOS) and discharge destination were recorded. Discharge destination was divided into home and facility. RESULTS: Multiple linear regression identified the ABMS II at admission as a significant predicator of discharge FIM in convalescent stroke patients (ß = .747, P < .05). Binary logistic regression analysis showed the ABMS II significantly predicting basic walk ability (odds ratio 1.29) and home discharge (odds ratio 1.241) of these patients. Receiver operating characteristic analysis indicated that an optimal cutoff of 18 points of ABMS II predicted basic walk ability (area under the curve = .863, P < .05) and home discharge (area under the curve = .827, P < .05). Moreover, a significant negative correlation between the ABSM II at admission and LOS was found (Correlation coefficients -.680, P < .05). CONCLUSIONS: Higher score of the ABMS II at admission predicted better functional recovery, shorter LOS and more possibility to home in convalescent stroke patients. This new, easy scale is expected to be widely used for stroke patients.

Asymmetric Epoxidation of 1,4-Naphthoquinones Catalyzed by Guanidine-Urea Bifunctional Organocatalyst.

An enantioselective nucleophilic epoxidation of 2-substituted 1,4-naphthoquinones in the presence of a newly developed guanidine-bisurea bifunctional organocatalyst with tert-butyl hydroperoxide (TBHP) as an oxidant is presented. 1,4-Naphthoquinones bearing substituents at C6, C7, and C2 were available for the reaction, and the corresponding epoxides were obtained with 88:12-95:5 er in 71-98% yields. DFT calculations indicated that substituents at C2 and C6 in the terminal Ar group of the catalyst 9k play a key role in controlling the stereochemical outcome.