[Observation and analysis of lens turbidity lesion induced by low intensity 635 nm laser radiation].

Objective: To study the characteristics of the lens turbidity after long-term exposure to low intensity 635nm laser. Methods: Cluster sampling method was adopted to select 812 employees in a laser leveler workshop in a city of Guangdong Province from January 2014 to December 2018. They were divided into the control group, diffuse reflection (DR) group and direct vision (DV) group for retrospective observation and analysis of lens turbidity. The laser irradiation intensity of each group was investigated, the position and shape of lens opacity were analyzed, and the influencing factors were statistically analyzed with the repeated measurement data of dichotomy. Results: The laser irradiance and radiant exposure of DV group were between 0.72×10(-4) and 9.92×10(-4) mW/cm(2) and between 2.61×10(-2) and 1.53 J/cm(2), respectively. The subjects were mainly diagnosed with lens turbidity lesion, especially for the DV group. Most of lesions occurred in the pole and periphery of the anterior cortex. The lesions exhibited multipoint patterns with greyish white color. The turbidity rates in DV group (before work and work for 1, 2, 3 years) were 0%, 1.99% (8/402) , 4.98% (20/402) and 6.72% (27/402) , respectively, in the order of observation points. The statistical analysis of single factor effect showed that the turbidity rate was higher in DV group and higher in the second year in the DV group (P<0.01) . Multi-factor analysis of the laser effect on the lens showed that the main effect between groups, between the observation point were statistically significant (P<0.05) , but no statistical significance in the interaction between group×observation points (P>0.05) . Conclusion: Lens turbidity lesion can be caused by long-term exposure to low intensity 635 nm laser, so the product safety classification should be strictly strengthened. It is necessary to strengthen the protection of laser photochemical damage in the production process.

Translational potentiation of messenger RNA with secondary structure in Xenopus.

Differential translation of messenger RNA (mRNA) with stable secondary structure in the 5' untranslated leader may contribute to the dramatic changes in protein synthetic patterns that occur during oogenesis and early development. Plasmids that contained the bacterial gene chloramphenicol acetyltransferase and which encoded mRNA with (hpCAT) or without (CAT) a stable hairpin secondary structure in the 5' noncoding region were transcribed in vitro, and the resulting mRNAs were injected into Xenopus oocytes, eggs, and early embryos. During early oogenesis, hpCAT mRNA was translated at less than 3 percent of the efficiency of CAT mRNA. The relative translational potential of hpCAT reached 100 percent in the newly fertilized egg and returned to approximately 3 percent after the midblastula transition.

Cloning and expression levels of genes relating to the ovulation rate of the Yunling black goat.

This study investigated the nucleotide sequences and tissue expression levels of genes relating to the ovulation rate in Yunling black goats, a famous Yunnan province, China, local breed with low fecundity. Five genes, FSHB, FSHR, BMP15, BMPR1B, and ESR2, were investigated; the complete cDNA sequences of these genes were 390, 2088, 1185, 1509, and 1585 bp, respectively, and compared with Boer goats (a more fecund breed), the sequence identities were 99%, 99%, 99%, 100%, and 99%, respectively. There were two base differences in FSHB and BMP15, four in FSHR, and three in ESR2. There were fewer follicles and oocytes in Yunling black goats than in Boer goats. Expression levels of FSHB, FSHR, and BMP15 genes in Yunling black goats were lower, and expression levels of BMPR1B and ESR2 genes were higher. Serum FSH content was lower in Yunling black goats, but serum estrogen content was higher. Protein expression levels of FSHR, BMP15, BMPR1B, and ESR2 in ovary and pituitary correlated positively with gene mRNA expression levels. In Yunling black goats, the mRNA expression levels of FSHB, FSHR, and BMP15 positively correlated with litter size, but those of BMPR1B and ESR2 correlated negatively. Together, base changes and variations in mRNA and protein expression levels of genes relating to the ovulation rate result in low fecundity in the Yunling black goat. Reduced BMP15 and FSHR levels may be related to the observed fewer oocytes and, consequently, fewer follicles.