Biosynthesis of Ag2Se nanoparticles as a broad-spectrum antimicrobial agent with excellent biocompatibility.

Silver (Ag)-containing nanomaterials have emerged as promising alternatives or adjuvants to antibiotics. Ongoing research is dedicated to enhance their antimicrobial efficacy, stability, biocompatibility, and environmental sustainability. Microorganism-synthesized Ag-containing nanomaterials offer distinct advantages, especially for various surface modification, which potentially fulfill these objectives. In this study, we present the synthesis of silver-selenium (Bio-Ag2Se) nanoparticles using a yeast strain, Rhodotorula mucilaginosa PA-1. These Bio-Ag2Se nanoparticles have small size with a narrow size distribution (12.3 ± 2.9 nm) and long-term stability. They demonstrate a broad antimicrobial spectrum and high antimicrobial efficacy at very low concentrations, effectively targeting microorganisms including Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, as well as pathogenic fungus Candida albicans. Furthermore, Bio-Ag2Se nanoparticles exhibit excellent efficacy to inhibit and eliminate biofilms formed by notorious pathogen S. aureus. In contrast, Bio-Ag2Se nanoparticles at effective antibacterial concentrations demonstrate favorable biocompatibility and do not show obvious cytotoxic effects on human and plant cells. To elucidate the antibacterial mechanisms of Bio-Ag2Se nanoparticles against S. aureus and E. coli, transcriptomic analysis and phenotypic examination were employed. The results reveal significant and broad up-regulation in carbon metabolism pathways in both S. aureus and E. coli, suggesting it as one of the major antibacterial mechanisms of Bio-Ag2Se. This study presents a green synthesis strategy for Ag-containing nanoparticles with promising applications.

Synthesis and biological evaluation of novel H6 analogues as drug resistance reversal agents.

Hederagenin is a naturally occurring pentacyclic triterpenoids compound with multiple pharmacological activities. We recently showed that H6, a synthetic derivative of hederagenin, could enhance the anticancer activity of paclitaxel in drug-resistant cells in vitro and in vivo, but showed poor solubility. With the aim of improving the drug resistant reversal activity of H6, here we designed and synthesized a series of novel H6 analogues. Our results showed that compound 10 at the concentration of 5 µM significantly enhanced the cytotoxicity of paclitaxel to drug-resistant KBV cells and sensitized cells to paclitaxel in arresting cells in G2/M phase and inducing apoptosis. We found that compound 10 might block the drug efflux of P-gp via stimulating P-gp ATPase activity. Importantly, compound 10 enhanced the efficacy of paclitaxel against KBV cancer cell-derived xenograft tumors. Finally, we summarized a preliminary structure-activity relationship of hederagenin by the drug resistant reversal activity of H6 analogues in vitro and compound 10 and H6in vivo. This study highlights the importance of nitrogen-containing derivatives of hederagenin C-28 in the development of novel drug resistance reversal agents.

Relationship between testis volume and types of spermatogenic cells from testicular biopsy in patients with azoospermia or cryptozoospermia / 中华男科学杂志

<p><b>OBJECTIVE</b>To study the relationship between the testis volume and types of spermatogenic cells derived from testicular biopsy in patients with azoospermia or cryptozoospermia.</p><p><b>METHODS</b>We collected testicular pathological biopsies from 492 infertile patients with azoospermia or cryptozoospermia reported in our hospital, classified them according to the testicular histological classification methods in WHO Manual for Standardized Investigation, Diagnosis and Management of the Infertile Male, and analyzed the relationship of the testis volume with the results of semen analyses and testicular histology.</p><p><b>RESULTS</b>Of the 492 cases, 90.5% (445/492) were azoospermia and 9.5% (47/492) cryptozoospermia; mature spermatozoa were present in the seminiferous tubules in 17.9% (88/492) but absent in 42.9% (211/492), and Sertoli cell-only syndrome indicated in 39.2% (193/492); the testis volume was < or = 10 ml in 38.6% (190/492) and < or = 5 ml in 7.9% (39/492). Cryptozoospermia was detected in 14.8% (13/88) of those with mature spermatozoa in the seminiferous tubules, in 11.4% (24/211) of those without, and in 5.2% (10/193) of those with Sertoli cell-only syndrome, with a significantly lower rate in the latter group than in the former two (P < 0.05).</p><p><b>CONCLUSION</b>Spermatogenesis of the testis may be focal and difficult to be completely reflected by a single testicular biopsy, and it may exist even if the testis volume is significantly below the reference value. The indications for testicular biopsy should not be improperly expanded. The WHO testicular histological classification methods have provided a convenient and effective guidance for further clinical examinations and establishment of a protocol.</p>

Chromosome abnormalities and Y chromosome microdeletions in patients with the azoospermia and cryptozoospermia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the incidence of the chromosome abnormalities and Y chromosome microdeletions in Chinese patients with azoospermia and cryptozoospermia.</p><p><b>METHODS</b>Conventional chromosomal karyotyping was used to analyze the chromosome abnormalities. Genomic DNA was extracted from peripheral blood samples and multiplex polymerase chain reactions (PCR) analyses were performed using specific primers to confirm the presence or absence of Y chromosome microdeletions. A total of 997 patients with azoospermia and cryptozoospermia were enrolled in the study.</p><p><b>RESULTS</b>The incidence of chromosome abnormalities in the patient with azoospermia and cryptozoospermia was 28.4%. The major abnormal karyotypes included 47,XXY, 46,XY (Y>G), 46,XX, chimera and translocations. The incidence of the Y chromosome microdeletions was 17.4%. They were mainly found in the karyotypes of 46,XY and 46,XY (Y>G).</p><p><b>CONCLUSION</b>Chromosome abnormalities were the most common hereditary causes of the patients with azoospermia and cryptozoospermia. The incidence of Y chromosome microdeletion was higher in the patients with karyotype of 46,XY and 46,XY (Y>G). Therefore, detection of the AZF microdeletion in these patients is helpful to determine the etiology and avoid the unnecessary treatment and vertical transmission of the genetic defects.</p>

Correlation between biological characteristics of volunteer donors and sperm parameters / 中华男科学杂志

<p><b>OBJECTIVE</b>To explore the correlation between the biological characteristics of volunteer donors and sperm parameters.</p><p><b>METHODS</b>Sperm parameters were analyzed for 778 primary volunteer donors by CASA system with standard methods recommended by WHO including sperm concentration, motility rate, VCL, VSL, ALH, LIN, STR and BCF, and their biological characteristics were recorded.</p><p><b>RESULTS</b>Of all the volunteer donors, students accounted for more than a third, 89.2 percent were under the age of 35 years, 71.6 percent between 166 and 175 cm in height, 91.7 percent of normal weight and 77.1 percent with college education. The median sperm concentration and motility rate were 107.00 x 10(6)/ml and 75 percent respectively. Age was weakly correlated with such semen indexes as concentration (r = 0.210, P = 0.000) , motility rate (r = 0.213, P = 0.000), volume (r = 0.165, P = 0.002), VAP (r = 0.259, P = 0.000), VSL (r = 0.281, P = 0.000), VCL (r = 0.190, P = 0.000), BCF (r = 0.243, P = 0.000) and LIN (r = 0.192, P = 0.000). The semen indexes of the 26-35 age group were a little better than those of the 20-25. Height showed no correlation to semen indexes. Education and occupation were somewhat related with other sperm parameters (P < 0.01) than ALH (P = 0.695/0.886).</p><p><b>CONCLUSION</b>Age, occupation and education bear some correlation with sperm parameters except ALH, while height has none with any of them.</p>