[Epidemiological pattern of abnormal urinary fluoride rates in population with occupational fluoride exposure in Shanghai].

Objective: To investigate the epidemiological features of abnormal urinary fluoride rates in population with occupational exposure, and its relationships with age, work years and gender in Shanghai. Methods: A questionnaire survey was conducted respectively in 4 999 exposed workers and 283 non-exposed people during 2012-2015. Their urine samples were collected in plastic bottles and the fluoride ion selective electrode method was used for urinary fluoride level analysis. Logistic regression model was used to estimate associations between the abnormal rates and demographic/socioeconomic status of the study subjects. Results: In the past 4 years, the abnormal urinary fluoride rates (≥1.6 mg/L) in the population with occupational exposure was about 14.38%, it was about 1.43% in the control groups without occupational exposure. Their geometric mean of urinary fluoride content was 0.95 mg/L and 0.46 mg/L, respectively. The incidences of the abnormal rates in those aged ≥50 years and 34-39 years were 19.15% and 22.39%, respectively. The abnormal rate in males was 16.87%, much higher than that in females (6.85%). The abnormal rate had an upward trend along with the increased work years, especially in those with work years of ≥20 years. The abnormal rate was 23.28% in those with work years of ≥20 years and 13.29% in those with work years of <4 years. The relative risk for abnormal urinary fluoride rates was higher in male group, older age group and longer work year group, the odds ratio was 2.28, 1.10 and 1.13, respectively. Conclusions: Serious challenges exist in occupational health supervision. The relevant national standards should be updated as soon as possible. Males, those aged >50 years, and those with longer work years are the risk groups for intervention measures. More efforts are needed, such as strengthening the innovative application of health examination data and the equalization of basic public health service with comprehensive occupational health supervision programs among off-farm workers in the new medical reform.

Antiemetic effects of combined methylprednisolone and tropisetron in mastectomy.

BACKGROUND: Combined dexamethasone and tropisetron have been reported more effective than a single drug therapy in preventing postoperative nausea and vomiting (PONV). However, the safety use of dexamethasone has been questioned recently because of the risk of secondary adrenal deficiency. Therefore, we hypothesized that combined tropisetron and methylprednisolone, a short-lasting corticoid, might provide effective prophylaxis of PONV with less effect on endogenous cortisol level. METHODS: In this study, 224 women undergoing modified radical mastectomy under general anesthesia were randomly divided into three groups: 1) receiving 10 mg tropisetron alone (T, N.=76); 2) 10 mg tropisetron and 8 mg dexamethasone (TD, N.=73); or 3) 10 mg tropisetron and 40 mg methylprednisolone (TM, N.=75) intravenously. Serum cortisol level, episodes of PONV and the need for rescue antiemetic medication were recorded during first 3 days after surgery. RESULTS: Serum cortisol significantly decreased in group TD (5.42±1.87 µg/dL), compared with group TM (14.38±2.01 µg/dL, P<0.01) and group T (19.52±1.53 µg/dL, P<0.001) in the first day postoperatively. In the first 24 hours, the incidence of vomiting was significantly higher in group T (15.8%), compared with group TD (5.5%, P<0.05) and group TM (5.3%, P<0.05), respectively. The overall request for a rescue antiemetic of group T was significantly higher, compared with group TD and group TM (P<0.05). CONCLUSION: Methylprednisolone-tropisetron combination is more effective than tropisetron alone, and as equally effective as dexamethasone-tropisetron combination for preventing acute PONV in mastectomy.

[Genetic analysis of gelatinization temperature in rice via microsatellite(SSR) markers].

Rice gelatinization temperature is an important character contributing to cooking quality. Here the inheritance of gelatinization temperature (GT), which was represented by alkali spreading value (ASV), was reported. Two parents, Balilla (japonica variety) and Nantehao (indica variety), which were significantly different on GT-ASV, were selected to construct a backcross population Balilla/Nantehao//Balilla containing 142 individuals. And ASV was investigated in the population, a continuous distribution with two obvious peaks was observed. It indicated that GT-ASV was controlled by one major gene, also modified by some minor genes. In order to map the major and minor genes and estimate the effects of genes. A total of 119 SSR markers were employed to construct a linkage map; further a genome-wide detection was carried out by interval mapping method. The results showed that 6 QTLs were detected, of which, qASV6-1 located on chromosome 6 was a major gene with 87.6% variance explained, and alleles from parent Nantehao could decrease the value. It shoud be the same locus as the alkali degeneration gene (alk). The other QTLs (qASV2, qASV3, qASV6-2, qASV9, and qASV11) all belong to minor genes, which were located on chromosome 2,3,6,9 and 11, respectively. In two parents, they carried the positive and negative alleles simultaneously. These results will be helpful for rice quality breeding and improvement.

[RFLP analysis of the effect of wide compatibility genes in Aus variety 'Dular'].

RFLP markers were employed to test whether the individuals possess wide compatibility genes (WCGs) in the progenies of Dular, which is one of the typical wide compatibility varieties in ecotype Aus rice. Meanwhile the characteristics of WCGs were also analysed. The results are shown as follows: (1) the effect of WCG at S-5 locus is better than the others, (2) the combination of different wide compatibility loci is obviously effective in increasing the spikelet fertility, (3) intraallelic interaction can cause japonica macrospore abortive, while interallelic interaction has some effects in fertility expression.

[Re-analysis of wide compatibility in rice].

Utilization of heterosis between rice subspecies has fascinated rice breeders for several decades. One of the main obstacles is the hybrid sterility in the F1 populations of subspecies crosses in rice. Wide compatibility varieties are considered to an important way to overcome the problem. But the genetics of the wide compatibility is controversial. This paper dealt with the problem through three kinds of triple crosses in which a wide compatibility variety, Ketan Nangka, was involved. Pollen fertility, spikelet fertility and the correlationship between the two fertilities were analyzed in the three kinds of triple crosses. The results suggested that male and female sterilities existed in indica-japonica hybrids at the same time, while the contribution of male sterility to spikelet fertility varied from cross to cross; The characteristic of wide compatibility in different triple crosses was coordinated with the hybrid sterility between the indica and japonica test varieties used; Ketan Nangka possessed the wide compatibility genes on the loci in which the male and female sterilities between the test varieties were involved; The genetics of wide compatibility gene S-5 fitted to one locus sporo-gametophytic interaction model.

[Chromosome location of a semidwarf gene sd-t in indica rice (O. sativa L.)].

For investigating the linkage group to which the semidwarf gene sd-t belongs, the crosses between Aitaiyin 2(ATY2), a variety of sd-t carrier in indica rice, and marker stocks as well as the trisomic lines of IR36 were made. The results indicated that the sd-t gene was linked to the marker genes Prp-b (Purple pericap b), lg(ligueless) and Wh(White hull). The recombination values estimated were 2.85% +/- 0.52% for sd-t to Prp-b, 27.90% +/- 3.81% for sd-t to lg and 38.62% +/- 2.99% for sd-t to Wh, respectively. It was inferred that the sd-t gene was located on chromosome 4 according to the established relationship between chromosomes and linkage groups.

[RFLP analysis on wide compatibility genes in rice variety dular of ecotype aus].

Dular is one of the typical wide compatibility varieties in ecotype Aus of rice. Genetic analysis on wide compatibility genes (WCG) from Dular based on triple crosses (indica//++Dular/japonica) was conducted. In the condition of being shaded for 7 days, the individual spikelet fertility segregated obviously, and the continuous distributions of spikelet fertility with a handful of peaks were observed. This suggested that the segregation of spikelet fertility in triple cross populations was controlled by one or more major genes, also modified by some minor genes. Based on 109 individuals of triple cross Nanjing 11 (indica)//++Dular/2533(japonica, a marker gene line, Rc and g), fertile and semisterile pools were set up by bulked segregant analysis, the RFLP analysis of the two pools led to the discovery of three chromosomal segments co-segregating with fertility. The one is on the interval RG213-C235 on chromosome 6. According to the previous studies, it may be the wide compatibility gene S5n. The other two were on the interval RG901-RG413 and G402-RG651 on chromosome 12, temporarily designated as Sd1(t)n and Sd2(t)n, respectively. Because of the continuous distribution for spikelet fertility, we also used a quantitative model to evaluate the effects of those three loci. On the basis of interval analysis with Mapmaker/QTL, 32.3% of the phenotypic variance associated with spikelet fertility was explained by the S5n (LOD = 9.03), and the other two chromosomal segments were responsible for 10.5%(LOD = 2.61) and 10.9%(LOD = 2.14) phenotypic variance, respectively. The results demonstrated that the wide compatibility variety Dular contained three WCGs. To introgress the three WCGs into a restorer line or an abortive line will overcome the hybrid sterility barrier of indica/japonica crosses, and the precise RFLP mapping will be useful for breeders to accumulate a few genes of interest into one cultivar by means of molecular marker assisted selection.

[Isolation and cytological identification of a desynaptic variant in rice].

A sterile variant was found from the population of a japonica rice variety Lunhui 422. Cytological investigation was conducted in meiosis. It is showed that the sterility was caused by desynapsis. As there were 8.69 bivalents in average occurred to be desynaptic, moreover, the most number of the desynaptic bivalents reached 12 at post diakinsis. It can be considered that the desynaptic variation is a complete desynapsis found in rice so far.

Cytological identification of an isotetrasomic in rice and its application to centromere mapping.

The aneuploid with isochromosome or telochromosome is ideal material for exploring the position of centromere in lingkage map. For obtaining these aneuploids in rice, the primary trisomics from triplo-1 to triplo-12 and the aneuploids derived from a triploid of indica rice variety Zhongxian 3037 were carefully investigated. From the offsprings of triplo-10, a primary trisomic of chromosome 10 of the variety, an isotetrasomic "triplo-10-1" was obtained. Cytological investigation revealed that a pair of extra isochromosomes of triplo-10-1 were come from the short arm of chromosome 10. In the offsprings of the isotetrasomic, a secondary trisomic "triplo-10-2", in which the extra- chromosome was an isochromosome derived from the short arm of chromosome 10, was identified. With the isotetrasomic, secondary trisomic, primary trisomic and diploid of variety Zhongxian 3037, different molecular markers were used for exploring the position of the centromere of chromosome 10. Based on the DNA dosage effect, it was verified that the molecular markers G1125, G333 and L169 were located on the short arm, G1084 and other 16 available molecular markers were on the long arm of chromosome 10. So the centromere of chromosome 10 was located somewhere between G1125 and G1084 according to the RFLP linkage map given by Kurata et al[1]. The distance from G1125 to G1084 was about 3.2 cM.

RFLP tagging of a new semidwarfing gene in rice.

A new rice semidwarfing gene which is not allelic tosd1, temporarily designated assdg, might be of use as a new source of semidwarfism in rice breeding programs. We report here the identification of a DNA marker closely linked to this gene. The DNA marker was identified by testing 120 mapped rice RFLP makers as hybridization probes for Southern analysis of a pair of nearly isogenic lines with or withoutsdg. Linkage association of the marker with the gene was verified using a F2 population segregating for semidwarfism. RFLP analysis showed thatsdg is closely linked to a single-copy DNA clone RZ182 on chromosome 5, with a distance of 4.3 centiMorgans between them. This marker may facilitate early selection for the semidwarfing gene in rice breeding programs.