Immunohistochemical and in situ hybridization studies of gonadotropin releasing hormone (GnRH) and its receptor in rat digestive tract

GnRH(LH-RH) is first discovered in the hypothalamus and found to have a role in regulation of reproduction. With the study on it deepening, GnRH was demonnstrated that it also exists in a number of organs beyond the hypothalamus and acts on extrapituitary organs. To study whether digestive tract synthesizes GnRH and its receptor and, if it does, by what cells. In the experiment, the locallizations of GnRH and its receptors in rat digestive tract were studied using immunohistochemistry and in situ hybridization. The parietal cells of gastric gland, the villous and glandular epithelium in small and large intestine and parasympathetic ganglion cells of myenteric plexus showed GnRH immunoreactivity; GnRH mRNA hybridization signal was detected. The epithelium of gastric pit and the cells above in digestive tract showed GnRH receptor immunoreactivity; GnRH receptor mRNA hybridization signal was detected. The immunoreactive and signal materials distributed in cytoplasm of all positive cells, with nuclei being immunonegative and with no hybridization signal. These results suggested that the digestive tract can produce GnRH and express GnRH receptor; GnRH may also be a gastrointestinal hormone.     

Tandemly repeated hexanucleotide at Tetrahymena rDNA free end is generated from a single copy during development

The linear extrachromosomal ribosomal DNA of Tetrahymena is generated from a single integrated copy during macronuclear development. The free ends of this extrachromosomal gene contain 20-70 tandem repeats of the hexanucleotide CCCCAA. We have determined the nucleotide sequence at the same (3') end of the single, integrated micronuclear gene. In contrast to the extrachromosomal gene, only a single CCCCAA sequence was found at this position. The same result was obtained from two independently isolated DNA clones, and was therefore not likely an artifact of cloning. Comparisons of the genomic DNA with the cloned fragment by Southern hybridization also supported this argument. Thus the tandemly repetitive hexanucleotide at the free ends of the extrachromosomal rDNA is not an inherited feature, and must be generated during the development of the macronucleus.     

New pollen classification of Chenopodiaceae for exploring and tracing desert vegetation evolution in eastern arid central Asia

Members of the Chenopodiaceae are the most dominant elements in the central Asian desert. The different genera and species within this family are common in desert vegetation types. Should it prove possible to link pollen types in this family to specific desert vegetation, it would be feasible to trace vegetation successions in the geological past. Nevertheless, the morphological similarity of pollen grains in the Chenopodiaceae rarely permits identification at the generic level. Although some pollen classifications of Chenopodiaceae have been proposed, none of them tried to link pollen types to specific desert vegetation types in order to explore their ecological significance. Based on the pollen morphological characters of 13 genera and 24 species within the Chenopodiaceae of eastern central Asia, we provide a new pollen classification of this family with six pollen types and link them to those plant communities dominated by Chenopodiaceae, for example, temperate dwarf semi‐arboreal desert (Haloxylon type), temperate succulent halophytic dwarf semi‐shrubby desert (Suaeda, Kalidium, and Atriplex types), temperate annual graminoid desert (Kalidium type), temperate semi‐shrubby and dwarf semi‐shrubby desert (Kalidium, Iljini, and Haloxylon types), and alpine cushion dwarf semi‐shrubby desert (Krascheninnikovia type). These findings represent a new approach for detecting specific desert vegetation types and deciphering ecosystem evolution in eastern central Asia.     

Comparing the Curative Effects between Femtosecond Laser-Assisted Cataract Surgery and Conventional Phacoemulsification Surgery: A Meta-Analysis

Purpose

To compare the outcomes of femtosecond laser-assisted cataract surgery (FLACS) with those of conventional phacoemulsification surgery (CPS) for age-related cataracts.

Methods

A comprehensive literature search of PubMed, EMBASE, and the Cochrane Controlled Trials Register was conducted to identify randomized controlled trials (RCT) and comparative cohort studies comparing FLACS with CPS. Endothelial cell loss percentage (ECL%), central corneal thickness (CCT), corrected and uncorrected distant visual acuity (CDVA and UDVA), and mean absolute error (MAE) of refraction were used as primary outcomes. Secondary outcomes included surgically induced astigmatism (SIA), mean effective phacoemulsification time (EPT), phacoemulsification power and circularity of the capsulorhexis.

Results

Nine RCTs and fifteen cohort studies including 4,903 eyes (2,861 in the FLACS group and 2,072 in the CPS group) were identified. There were significant differences between the two groups in ECL% at one week, about one month and three months postoperatively, in CCT at one day, about one month postoperatively and at the final follow-up, in CDVA at one week postoperatively, and in UDVA at the final follow-up. Significant differences were also observed in MAE, EPT, phacoemulsification power, and the circularity of capsulorhexis. However, no significant differences were observed in CDVA at one week postoperatively or in surgically induced astigmatism.

Conclusions

Compared to CPS, FLACS is a safer and more effective method for reducing endothelial cell loss and postoperative central corneal thickening as well as achieving better and faster visual rehabilitation and refractive outcomes. However, there is no difference in final CDVA and surgically induced astigmatism between the two groups.     

交联琼脂糖珠固定化蛋白酶在纯化牛肺Kunitz抑制剂中的应用

本文介绍了珠状交联琼脂糖及以此作为载体,经氯代环氧丙烷活化后与蛋白酶(胰蛋白酶或糜蛋白酶)结合,制成固定化蛋白酶亲和吸附剂,进而用以亲和层析牛肺提取液中的Kunitz抑制剂的方法。纯化出的抑制剂在SDS-聚丙烯酰胺凝胶电泳上呈现单一条带,与参照物Trasytol(商品Kunitz抑制剂)具有相对应的电泳迁移率,其分子量也相符。纯化产品每毫克蛋白的抑制活力相当于16 000胰蛋白酶BAEE单位。纯化效果为90倍,收率约85％。     

Changes in the Prevalence of Rheumatic Diseases in Shantou,China, in the Past Three Decades: A COPCORD Study

This study aimed to clarify changes in the prevalence of rheumatic diseases in Shantou, China, in the past 3 decades and validate whether stair-climbing is a risk factor for knee pain and knee osteoarthritis (KOA). The World Health Organization-International League Against Rheumatism Community Oriented Program for Control of Rheumatic Diseases (COPCORD) protocol was implemented. In all, 2337 adults living in buildings without elevators and 1719 adults living in buildings with elevators were surveyed. The prevalence of rheumatic pain at any site and in the knee was 15.7% and 10.2%, respectively; both types of pain had a significantly higher incidence in residents of buildings without elevators than was reported by people who lived in buildings with elevators (14.9% vs. 10.6% and 11.32% vs. 8.82%, respectively) (both P < 0.0001). The prevalence of rheumatic pain in the neck, lumbar spine, shoulder, elbow, and foot was 5.6%, 4.5%, 3.1%, 1.4%, and 1.8%, respectively; these findings were similar to the data from the 1987 rural survey, but were somewhat lower than data reported in the urban and suburban surveys of the 1990s, with the exception of neck and lumbar pain. The prevalence of KOA, gout, and fibromyalgia was 7.10%, 1.08%, and 0.07%, respectively, and their prevalence increased significantly compared with those in previous studies from the 20^th century. There were no significant differences in the prevalence of rheumatoid arthritis (RA) (0.35%) or ankylosing spondylitis (AS) (0.31%) compared to that reported in prior surveys. The prevalence of KOA was higher in for residents of buildings without elevators than that in those who had access to elevators (16–64 years, 5.89% vs. 3.95%, P = 0.004; 16->85 years, 7.64% vs. 6.26%, P = 0.162). The prevalence of RA and AS remained stable, whereas that of KOA, gout, and fibromyalgia has increased significantly in Shantou, China, during the past 3 decades. Stair-climbing might be an important risk factor for knee pain and KOA.     

ZAKβ antagonizes and ameliorates the cardiac hypertrophic and apoptotic effects induced by ZAKα

ZAK (sterile alpha motif and leucine zipper containing kinase AZK), a serine/threonine kinase with multiple biochemical functions, has been associated with various cell processes, including cell proliferation, cell differentiation, and cardiac hypertrophy. In our previous reports, we found that the activation of ZAKα signaling was critical for cardiac hypertrophy. In this study, we show that the expression of ZAKα activated apoptosis through both a FAS‐dependent pathway and a mitochondria‐dependent pathway by subsequently inducing caspase‐3. ZAKβ, an isoform of ZAKα, is dramatically expressed during cardiac hypertrophy and apoptosis. The interaction between ZAKα and ZAKβ was demonstrated here using immunoprecipitation. The results show that ZAKβ has the ability to diminish the expression level of ZAKα. These findings reveal an inherent regulatory role of ZAKβ to antagonize ZAKα and to subsequently downregulate the cardiac hypertrophy and apoptosis induced by ZAKα.     

Comparison of neurotoxicity of different aggregated forms of Aβ40, Aβ42 and Aβ43 in cell cultures

The abnormal deposition of amyloid‐β (Aβ) peptides in the brain is the main neuropathological hallmark of Alzheimer's disease (AD). Amyloid deposits are formed by a heterogeneous mixture of Aβ peptides, among which the most studied are Aβ40 and Aβ42. Aβ40 is abundantly produced in the human brain, but the level of Aβ42 is remarkably increased in the brain of AD patients. Aside from Aβ40 and Aβ42, recent data have raised the possibility that Aβ43 peptides may be instrumental in AD pathogenesis. Besides its length, whether the Aβ aggregated form accounts for the neurotoxicity is also particularly controversial. Aβ fibrils are generally considered as key pathogenic substances in AD pathogenesis. Nevertheless, recent data implicated soluble Aβ oligomers as the main cause of synaptic dysfunction and memory loss in AD. To further address this uncertainty, we analyzed the neurotoxicity of different Aβ species and Aβ forms at the cellular level. The results showed that Aβ42 could form oligomers significantly faster than Aβ40 and Aβ43 and Aβ42 oligomers showed the greatest level of neurotoxicity. Regardless of the length of Aβ peptides, Aβ oligomers induced significantly higher cytotoxicity compared with the other two Aβ forms. Surprisingly, the neurotoxicity of fibrils in PC12 cells was only marginally but not significantly stronger than monomers, contrary to previous reports. Altogether, our findings demonstrate the high pathogenicity of Aβ42 among the three Aβ species and support the idea that Aβ42 oligomers contribute to the pathological events leading to neurodegeneration in AD. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.     

Identification of cry1I-type genes from Bacillus thuringiensis strains and characterization of a novel cry1I-type gene

A PCR-restriction fragment length polymorphism method for identification of cry1I-type genes from Bacillus thuringiensis was established by designing a pair of universal primers based on the conserved regions of the genes to amplify 1,548-bp cry1I-type gene fragments. Amplification products were digested with the Bsp119I and BanI enzymes, and four kinds of known cry1I-type genes were successfully identified. The results showed that cry1I-type genes appeared in 95 of 115 B. thuringiensis isolates and 7 of 13 standard strains. A novel cry1I-type gene was found in one standard strain and six isolates. The novel cry1I gene was cloned from B. thuringiensis isolate Btc007 and subcloned into vector pET-21b. Then it was overexpressed in Escherichia coli BL21(DE3). The expressed product was shown to be toxic to the diamondback moth (Plutella xylostella), Asian corn borer (Ostrinia furnacalis), and soybean pod borer (Leguminivora glycinivorella). However, it was not toxic to the cotton bollworm (Helicoverpa armigera), beet armyworm (Spodoptera exigua), or elm leaf beetle (Pyrrhalta aenescens) in bioassays. Subsequently, the Cry protein encoded by this novel cry gene was designated Cry1Ie1 by the B. thuringiensis delta-endotoxin nomenclature committee.