Human sperm cryopreservation in assisted reproductive technology is the only proven method that enables infertile men to father their own children. However, freezing and thawing reduces spermatozoon motility, viability, and fertilizing ability. An association between dysfunctional spermatozoa due to cryoinjury and protein changes has not been established. We investigated through proteomic analysis the differential protein characteristics between freeze-thawed and fresh sperm samples obtained from nine normozoospermic donors. Twenty-seven proteins differed in abundance between the two groups, and results were verified for four proteins via Western blot and immunofluorescent staining. These proteins are putatively involved in sperm motility, viability, acrosomal integrity, ATP and isocitrate content, mitochondrial membrane potential, capacitation, acrosome reaction, and intracellular calcium concentration. These marked differences suggest that dysfunctional spermatozoon after cryopreservation may be due to protein degradation and protein phosphorylation.

Background The aim of this paper was to conduct a baseline survey of HPV infection in unvaccinated women in Xinjiang Uyghur Autonomous Region before the mass use of HPV vaccine. Methods Between 2008 and 2018, the HPV genotype detected by a PCR-based hybridization gene chip assay of 37,722 women who were from Gynecology Department and Health Management Center of the First Affiliated Hospital of Xinjiang Medical University were tested HPV genotype by a PCR-based hybridization gene chip assay. All statistical analysis methods were performed with this statistical software including Python version 3.6.1, R Software 3.5.1 and Excel 2011. Results The total positive rate for HPV was 14.02%, the most prevalent genotypes were HPV 16 (3.79%), HPV 52 (2.47%), HPV 58 (1.76%), HPV 53 (1.35%) and HPV 31 (0.72%). The single infection (11.34%) and high-risk HPV (HR-HPV) infection (9.72%) was the main prevalence of HPV. Age-specific HPV distribution was presented as a bimodal curve, while the youngest age group (≤25 years) presented the highest HPV infection rate (20.78%), which was followed by a second peak for the 36–40 age group. According to the ethnic stratification, the HPV infection prevalence ranging from the high to low was: Mongol (16.36%), Hui (15.15%), Kazak (14.47%), Han (14.43%), Other (14.37%), Uygher (10.96%). From 2009 to 2013, the HPV infection rate fluctuated but did not changed much. It peaked in 2014 and then fell significantly, reached the bottom point in 2017 and rose slightly in 2018. In 2015, the infection rate of HPVl6 and 52 in the population was almost the same (both 3.40%) the infection rate of HPV52 type (3.31%) was higher than that of HPVl6 type (2.18%) and became the dominant type in 2016. Conclusions We present data regarding the prevalence and type distribution of HPV infection, which could serve as the valuable reference to guide nationwide cervical cancer screening. These baseline data enable the estimates of maximum HPV vaccine impact across time and provide critical reference measurements which are important to the assess of clinical benefits and potential harms in HPV vaccination and the increase in non-vaccine HPV types.

Hexagonal boron nitride (h-BN) catalyst has recently been reported to be highly selective in oxidative dehydrogenation of propane (ODHP) for olefin production. In addition to propene, ethylene also forms with much higher overall selectivities to C2-products than to C1-products. In this work, we report that the reaction pathways over the h-BN catalyst are different from the V-based catalysts in ODHP. Oxidative coupling reaction of methyl, an intermediate from the cleavage of C─C bond of propane, contributes to the high selectivities to C2-products, leading to more C2-products than C1-products over the h-BN catalyst. This work not only provides insight into the reaction mechanisms involved in ODHP over the boron-based catalysts but also sheds light on the selective oxidation of alkanes such as direct upgrading of methane via oxidative upgrading to ethylene or CHxOy on boron-based catalysts.

The recent emergence of the Omicron variant has raised concerns on vaccine efficacy and the urgent need to study more efficient vaccination strategies. Here we observed that an mRNA vaccine booster in individuals vaccinated with two doses of inactivated vaccine significantly increased the plasma level of specific antibodies that bind to the receptor-binding domain (RBD) or the spike (S) ectodomain (S1 + S2) of both the G614 and the Omicron variants, compared to two doses of homologous inactivated vaccine. The level of RBD- and S-specific IgG antibodies and virus neutralization titers against variants of concern in the heterologous vaccination group were similar to that in individuals receiving three doses of homologous mRNA-vaccine or a boost of mRNA vaccine after infection, but markedly higher than that in individuals receiving three doses of a homologous inactivated vaccine. This heterologous vaccination regime furthermore significantly enhanced the RBD-specific memory B cell response and S1-specific T cell response, compared to two or three doses of homologous inactivated vaccine. Our study demonstrates that mRNA vaccine booster in individuals vaccinated with inactivated vaccines can be highly beneficial, as it markedly increases the humoral and cellular immune responses against the virus, including the Omicron variant.

MicroRNAs are small, non-coding RNA molecules that regulate gene expression, and miR-124 is the most abundant miRNA in the brain. Studies have shown that miR-124 is clearly reduced in the ischemic brain after stroke; however, the role of miR-124 after stroke is less well studied. Using TargetScan, MicroCosm Targets version 5, and microRNA.org databases, we identified miR-124 as a possible regulator of the DNA repair protein Ku70. We validated that Ku70 is a target for miR-124 with a luciferase reporter activity assay. Moreover, adult rats subjected to focal cerebral ischemia exhibited a substantial reduction of miR-124 expression, which was inversely upregulated by Ku70 expression. In vivo treatment with miR-124 antagomir effectively enhanced Ku70 mRNA and protein levels in the ischemic region. Furthermore, knockdown of cerebral miR-124 reduced cell death and infarct size and improved neurological outcomes. Our data demonstrate that miR-124 is an endogenous regulator of Ku70 that improves ischemia/reperfusion (I/R)-induced brain injury and dysfunction.

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Direct oxidation of methane to value-added C1 chemicals (e.g. HCHO and CO) provides a promising way to utilize natural gas sources under relatively mild conditions. Such conversions remain, however, a key selectivity challenge, resulting from the facile formation of undesired fully-oxidized CO2. Here we show that B2O3-based catalysts are selective in the direct conversion of methane to HCHO and CO (~94% selectivity with a HCHO/CO ratio of ~1 at 6% conversion) and highly stable (over 100 hour time-on-stream operation) conducted in a fixed-bed reactor (550 °C, 100 kPa, space velocity 4650 mL gcat−1 h−1). Combined catalyst characterization, kinetic studies, and isotopic labeling experiments unveil that molecular O2 bonded to tri-coordinated BO3 centers on B2O3 surfaces acts as a judicious oxidant for methane activation with mitigated CO2 formation, even at high O2/CH4 ratios of the feed. These findings shed light on the great potential of designing innovative catalytic processes for the direct conversion of alkanes to fuels/chemicals.

Choroidal neovascularization (CNV) is a common cause of severe and irreversible visual loss; however, the treatment of CNV has been hindered by its complex and poorly understood pathogenesis. It has been postulated that bone marrow (BM)-derived cells (BMCs) contribute to CNV, but little is known about the role of mesenchymal stem cells (MSCs) in CNV and their therapeutic potential for CNV treatment. We found that BM-derived MSCs transplanted by intravenous injection into laser-induced CNV mouse models were specifically recruited into CNV lesions, where they differentiated into multiple cell types and participated in the development of neovascularization, without stagnation in other organs. By taking advantage of this recruitment potential, engineered MSCs were used to produce the antiangiogenic pigment epithelial-derived factor (PEDF) at the CNV sites, thereby inhibiting the growth of CNVs and stimulating regressive features. Further studies indicated that the effect may be mediated, at least partly, by retinal pigment epithelial (RPE) cells, which function as important regulators for CNV development. These results suggest that MSCs contribute to CNV and could serve as delivery vehicles of antiangiogenic agents for the treatment of a range of CNV-associated diseases.