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In recent years, the incidence of teratospermia has been increasing, and it has become a very important factor leading to male infertility. The research on the molecular mechanism of teratospermia is also progressing rapidly. This article briefly summarizes the clinical incidence of teratozoospermia, and makes a retrospective summary of related studies reported in recent years. Specifically discussing the relationship between gene status and spermatozoa, the review aims to provide the basis for the genetic diagnosis and gene therapy of teratozoospermia.
Iodine is an important element in thyroid hormone biosynthesis. Thyroid function is regulated by the hypothalamic–pituitary–thyroid axis. Excessive iodine leads to elevated thyroid-stimulating hormone (TSH) levels, but the mechanism is not yet clear. Type 2 deiodinase (Dio2) is a Se-containing protease that plays a vital role in thyroid function. The purpose of this study was to explore the role of hypothalamus Dio2 in regulating TSH increase caused by excessive iodine and to determine the effects of iodine excess on thyrotropin-releasing hormone (TRH) levels. Male Wistar rats were randomised into five groups and administered different iodine dosages (folds of physiological dose): normal iodine, 3-fold iodine, 6-fold iodine, 10-fold iodine and 50-fold iodine. Rats were euthanised at 4, 8, 12 or 24 weeks after iodine administration. Serum TRH, TSH, total thyroxine (TT4) and total triiodothyronine (TT3) were determined. Hypothalamus tissues were frozen and sectioned to evaluate the expression of Dio2, Dio2 activity and monocarboxylate transporter 8 (MCT8). Prolonged high iodine intake significantly increased TSH expression (P < 0·05) but did not affect TT3 and TT4 levels. Prolonged high iodine intake decreased serum TRH levels in the hypothalamus (P < 0·05). Dio2 expression and activity in the hypothalamus exhibited an increasing trend compared at each time point with increasing iodine intake (P < 0·05). Hypothalamic MCT8 expression was increased in rats with prolonged high iodine intake (P < 0·05). These results indicate that iodine excess affects the levels of Dio2, TRH and MCT8 in the hypothalamus.
Dietary salt intake may vary depending on different lifestyles. We aimed to estimate the different salt intakes and evaluate the knowledge and self-awareness about salt among people speaking the Teochew, Teochew–Hakka and Hakka dialects in the Chaoshan region of southern China.
The study followed a cluster sampling of residents in Chaoshan region. General characteristics, lifestyles, health status as well as knowledge and self-awareness related to salt intake were investigated using a questionnaire. Anthropometric variables as well as Na and K excretion in a 24-h urine collection were measured.
Chaoshan region of China.
Four hundred fifteen adults who spoke only one of these three dialects.
The salt intake of adults who spoke the Teochew, Teochew–Hakka and Hakka dialects was 7·19 (interquartile range (IQR) 5·29–10·17), 9·03 (IQR 6·62–11·54) and 10·12 (IQR 7·61–12·82) g/d, respectively, with significant differences between Teochew and Teochew–Hakka speakers and between Teochew and Hakka speakers (both P < 0·05). The Na:K ratio for adults who spoke the three dialects was 3·00 (IQR 2·00–4·11), 3·50 (IQR 2·64–4·82) and 4·52 (IQR 3·35–5·97), respectively, and differed significantly among the groups (all P < 0·05). Multiple linear regression analysis showed increased Na:K ratio associated with hypertension (β = 0·71, P = 0·043) in Hakka speakers. Knowledge and self-awareness about salt intake were poor in this population.
Salt intake was closely related to lifestyles and was higher than the upper limit (5 g/d) recommended by the WHO in adults of Chaoshan, especially those speaking the Hakka dialect.
Previous neuroimaging studies demonstrated that retinal detachment (RD) subjects were associated with abnormal spontaneous brain activities; however, whether the altered interhemispheric functional connectivity (FC) occurred in RD patients remains unknown. The current study tried to explore the alternations of interhemispheric FC of the whole brain in unilateral RD patients using the voxel-mirrored homotopic connectivity (VMHC) method and their connections to clinical features. Methods: We recruited 30 patients with RD (16 males and 14 females) and 30 healthy controls (HCs) (16 males and 14 females) whose age and sex were closely matched. All subjects underwent the rs-fMRI scans. The VMHC method was applied to directly assess the hemispheres’ functional interaction. The VMHC in these brain areas, which could be used as biomarkers to differentiate RD from HC, was identified by the receiver operating characteristic (ROC) curve analyses. The relations between these patients’ clinical features and their mean VMHC signal values in multiple brain regions were calculated by Pearson correlation analysis. Results: RD patients had significantly lower VMHC values than HCs in the bilateral occipital lobe (Brodmann areas, BA 18), bilateral superior temporal gyrus (BA 39), and bilateral cuneus (BA 19). Moreover, the mean VMHC signal values of the bilateral cuneus were in positive correlation with the duration of the RD (r = 0.446, P = 0.013). Conclusion: Our results provided an evidence of disturbed interhemispheric FC in the visual area occurred in RD patients, which might provide some useful information to understand the neural mechanism of RD patients with acute vision loss. Furthermore, the VMHC values might indicate the progress of the RD.
Studies quantifying relationships between floods and diarrheal diseases have mainly been conducted in low-latitude regions. It’s therefore increasingly important to examine these relationships in midlatitude regions, where they may have significant public health implications. This study aimed to examine the association between floods and bacillary dysentery in the city of Dalian, China.
A generalized additive mixed model was applied to examine the association between floods and bacillary dysentery. The relative risk (RR) of flood impact on bacillary dysentery was estimated.
A total of 18,976 cases of bacillary dysentery were reported in Dalian during the study period. Two weeks’ lagged effect was detected from the impact of floods on bacillary dysentery. The RR of flood impact on bacillary dysentery was 1.17 (95% CI: 1.03-1.33).
Floods have significantly increased the risk of bacillary dysentery in Dalian. More studies should focus on the association between floods and infectious diseases in different regions. Our findings have significant implications for managing the negative health impact of floods in the midlatitude region of China. (Disaster Med Public Health Preparedness. 2017;11:190–195)
Thermal stress can induce birefringence in a laser medium, which can cause depolarization of the laser. The depolarization effect will be very severe in a high-average-power laser. Because the depolarization will make the frequency doubling efficiency decline, it should be compensated. In this paper, the thermal characteristics of two kinds of materials are analyzed in respect of temperature, thermal deformation and thermal stress. The depolarization result from thermal stress was simulated. Depolarization on non-uniform pumping was also simulated, and the compensation method is discussed.
The high repetition rate 10 J/10 ns Yb:YAG laser system and its key techniques are reported. The amplifiers in this system have a multi-pass V-shape structure and the heat in the amplifiers is removed by means of laminar water flow. In the main amplifier, the laser is four-pass, and an approximately 8.5 J/1 Hz/10 ns output is achieved in the primary test. The far-field of the output beam is approximately 10 times the diffraction limit. Because of the higher levels of amplified spontaneous emission (ASE) in the main amplifier, the output energy is lower than expected. At the end we discuss some measures that can improve the properties of the laser system.