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Lu L, Zheng L, Si Y, Chen Z, Luo W, Oh S, King P. Abberrant Posttranscriptional Regulation and Protein Degradtion of TDP-43 and FUS to Stress Respone in ALS (P03.181). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.p03.181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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302
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Zheng L, Yang WW, Guo JY, Jia YR, Sun LX. Stability of daphnoretin in vitro. DIE PHARMAZIE 2012; 67:277-282. [PMID: 22570931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The stability of daphnoretin in sodium phosphate buffers at different pH and temperature, and in different biological samples at 37 degrees C was investigated using HPLC with UV detector set at 345 nm. Daphnoretin degraded rapidly in alkaline environment and was stable in acidic environment. Daphnoretin was stable in simulated gastrointestinal liquid, stomach contents, gastric mucosa and colon contents; it was unstable in plasma, liver homogenates, small intestine contents, small intestinal mucosa and blind gut contents. The stability of daphnoretin in plasma and other biomaterials could have a significant impact on its absorption.
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303
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Leng T, Jaben K, Zheng L, Yang J, Paulus Y, Moshfeghi A, Maltenfort M, Campbell P, Ratliff J, Moshfeghi D. The influence of medical school and residency training program upon choice of an academic career and academic productivity among otolaryngology faculty in the United States of America: Our experience of 1433 academic otolaryngologists. Clin Otolaryngol 2012; 37:58-62. [DOI: 10.1111/j.1749-4486.2011.02402.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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304
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Crippen T, Zheng L, Sheffield C, Tomberlin J, Beier R, Yu Z. Transient gut retention and persistence of Salmonella through metamorphosis in the lesser mealworm, Alphitobius diaperinus (Coleoptera: Tenebrionidae). J Appl Microbiol 2012; 112:920-6. [DOI: 10.1111/j.1365-2672.2012.05265.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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305
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Li C, Zheng L, Sun Y, Wang C, Li W, Lu C, Zhou X. No association between the G196A and C270T polymorphism of the brain-derived neurotrophic factor gene and male infertility. RUSS J GENET+ 2012. [DOI: 10.1134/s1022795412030076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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306
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Li C, Zheng L, Sun Y, Wang C, Li W, Lu C, Zhou X. No association between the G196A and C270T polymorphism of the brain-derived neurotrophic factor gene and male infertility. GENETIKA 2012; 48:405-407. [PMID: 22679788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Brain-derived neurotrophic factor (BDNF) plays important roles in neuronal development and reproductive action. Abnormal expression of BDNF gene has been detected in human sperm and seminal serum. In the present study, we investigated the possible association of G196A and C270T polymorphism of BDNF gene with male infertility. The genotypes of the G196A and C270T polymorphisms were in Hardy-Weinberg equilibrium both in fertile and infertile group. The genotype distribution frequencies were similar between infertile and fertile group. The results showed that the G196A and C270T polymorphism of the BDNF gene is unrelated to the male infertility, at least in a Chinese population.
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307
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Zheng L, Oh ST, Jeon JY, Moon BH, Kwon HS, Lim SU, An BK, Kang CW. The Dietary Effects of Fermented Chlorella vulgaris (CBT(®)) on Production Performance, Liver Lipids and Intestinal Microflora in Laying Hens. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2012; 25:261-6. [PMID: 25049560 PMCID: PMC4093139 DOI: 10.5713/ajas.2011.11273] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 10/28/2011] [Indexed: 12/24/2022]
Abstract
Fermented Chlorella vulgaris CBT® was evaluated for its effects on egg production, egg quality, liver lipids and intestinal microflora in laying hens. One hundred and eight Hy-line Brown layers (n = 108), 80 wk of age, were fed a basal diet supplemented with CBT® at the level of 0, 1,000 or 2,000 mg/kg, respectively for 42 d. Egg production was measured daily and egg quality was measured every two weeks. Five eggs from each replicate were collected randomly to determine egg quality. Egg production increased linearly with increasing levels of CBT® supplementation (p<0.05), although there was no significant effect of treatment on feed intake. Egg yolk color (p<0.001) and Haugh unit (p<0.01) improved linearly with increasing dietary CBT®. Hepatic triacylglycerol level was linearly decreased with increasing dietary CBT® (p<0.05). The supplemental CBT® resulted in linear (p<0.001) and quadratic (p<0.01) response in population of cecal lactic acid bacteria. In conclusion, fermented Chlorella vulgaris supplemented to laying hen diets improved egg production, egg yolk color, Haugh unit and positively affected the contents of hepatic triacylglycerol and the profiles of cecal microflora.
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308
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Iyer D, Zheng L, Williams ML, Tracey BH, Gozani SN. A novel method of detection and classification of motor nerve late-wave activity. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2012; 2011:7845-8. [PMID: 22256158 DOI: 10.1109/iembs.2011.6091933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In motor nerve conduction studies, important diagnostic information is provided by the late-wave responses, comprised of F-waves, A-waves, and repeaters. Late-waves in addition to contamination from power line interference and baseline disturbance, are of low amplitude and random in nature. This makes computer-based analysis of late-wave activity very challenging, especially the computer-based F-wave onset latency assignment. Currently available algorithms assign latency independently on a trace-by-trace basis without considering the information present in an entire ensemble of traces. A novel algorithm that takes into account the ensemble information for segmenting and classifying regions of late-wave data is described in this paper, which in turn can be used to improve the performance of computer-based F-wave onset latency assignment.
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309
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Guo W, Liu J, Zheng L, Xu H, Liu Y, Li Y. Capacity study of multiuser cooperative networks with fixed-gain relays. IET NETWORKS 2012. [DOI: 10.1049/iet-net.2012.0028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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310
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Zheng L, Luo W, Zhang Q, Liu J. 1.134 THE EFFECTS OF URIC ACID ON NEURONAL DIFFERENTIATED PC12 CELLS AGAINST THE TOXICITY INDUCED BY ROTENONE. Parkinsonism Relat Disord 2012. [DOI: 10.1016/s1353-8020(11)70248-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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311
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Rodewald UC, Zheng L, Heying B, Xu X, Su L, Xu J, Pöttgen R. Rare Earth Site Preference in the Doped Laser Host Material Sc2SiO5. A Single-Crystal X-Ray Study. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2012. [DOI: 10.5560/znb.2012.67b0113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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312
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Zheng L, Chen Z, Itzek A, Herzberg MC, Kreth J. CcpA regulates biofilm formation and competence in Streptococcus gordonii. Mol Oral Microbiol 2011; 27:83-94. [PMID: 22394467 DOI: 10.1111/j.2041-1014.2011.00633.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Streptococcus gordonii is an important member of the oral biofilm community. As an oral commensal streptococcus, S. gordonii is considered beneficial in promoting biofilm homeostasis. CcpA is known as the central regulator of carbon catabolite repression in Gram-positive bacteria and is also involved in the control of virulence gene expression. To further establish the role of CcpA as central regulator in S. gordonii, the effect of CcpA on biofilm formation and natural competence of S. gordonii was investigated. These phenotypic traits have been suggested to be important to oral streptococci in coping with environmental stress. Here we demonstrate that a CcpA mutant was severely impaired in its biofilm-forming ability, showed a defect in extracellular polysaccharide production and reduced competence. The data suggest that CcpA is involved in the regulation of biofilm formation and competence development in S. gordonii.
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313
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Balogh K, Asa SL, Zheng L, Cassol C, Cheng S, Ezzat S. The insulin resistance Grb14 adaptor protein promotes thyroid cancer ret signaling and progression. Oncogene 2011; 31:4012-21. [PMID: 22158039 PMCID: PMC3954818 DOI: 10.1038/onc.2011.569] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The growth factor receptor-bound protein (Grb) 14 is an adapter molecule of the Grb7/10/14 family with characteristic BPS domains serving to avidly bind tyrosine kinases. Grb14 inhibits insulin receptor (IR) catalytic activity through interaction with the BPS domain and impedes peptide substrate binding. Members of this Grb family have also been shown to interact with other kinases through their SH2 domain. Here we examined the functional role of Grb14 in thyroid cancer using loss- and gain-of-function approaches. Stable knockdown of Grb14 in thyroid cancer cells facilitated insulin receptor signaling. In contrast, RET phosphorylation was diminished in concert with reduced activation of Akt and STAT3. Loss of Grb14 also resulted in diminished cell proliferation and invasion both in vitro and in mouse flank xenografts. In complementary studies, forced expression of Grb14 interrupted insulin receptor signaling but facilitated RET activation, STAT3, and Akt phosphorylation. Consistent with these findings Grb14 over-expression enhanced cell invasion and resulted in striking metastases in an orthotopic thyroid cancer mouse xenograft model. Primary human thyroid cancer microarrays revealed a positive correlation between Grb14 expression and invasive behavior. Our findings uncover a new role for Grb14 in finely tuning receptor signaling and modulating thyroid cancer progression.
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314
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Feng H, Zhu XT, Qi ZM, Wang QH, Wang GG, Pan YY, Li Y, Zheng L, Jiang YJ, Shang H, Cui L, Cao YM. Transient Attenuated Foxp3 Expression on CD4+ T cells Treated with 7D4 mAb Contributes to the Control of Parasite Burden in DBA / 2 Mice Infected with Lethal Plasmodium chabaudi chabaudi AS. Scand J Immunol 2011; 75:46-53. [DOI: 10.1111/j.1365-3083.2011.02622.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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315
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Xue P, Zheng W, Zhang M, Zheng L. Development of real-time RT-PCR for human metapneumovirus. Acta Virol 2011; 55:285-6. [PMID: 21978165 DOI: 10.4149/av_2011_03_285] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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316
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Stevens K, Zheng L. Acute administration of cotinine to DBA/2 mice increases conditioning amplitude in the sensory inhibition model. Biochem Pharmacol 2011. [DOI: 10.1016/j.bcp.2011.07.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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317
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Lv R, Zheng L, Zhu Z, Pan L, Huang J, Hsiang T. First Report of Stem Blight of Eleocharis dulcis Caused by Phoma bellidis in China. PLANT DISEASE 2011; 95:1190. [PMID: 30732029 DOI: 10.1094/pdis-05-11-0438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Eleocharis dulcis is a perennial herbaceous plant in the family Cyperaceae, which is native to China and India where it grows well in moist-to-wet soils. It is commonly used as a fruit or a vegetable. From August 2009 to December 2010, symptoms were observed on E. dulcis stems in Tuanfeng County, Hubei, China, with the crop area affected estimated to be more than 1,300 ha per year. Corm yield was reduced by 20% on average with as much as 60% yield losses in some fields. Lesions were initially small, red-brown, and oval or circular that enlarged to produce apical necrosis and extending until the stems withered, usually within 2 months. To obtain isolates, diseased tissue was disinfested for 1 min in 0.1% mercuric chloride solution, rinsed with sterilized water, and plated on potato dextrose agar. Isolates with similar morphological characteristics were consistently recovered. Three isolates, CTF-3, CTF-10, and CTF-11, were used to further evaluate characteristics of the pathogen. After 7 days, white colonies were 76 to 80 mm across on oatmeal agar (OA) with sparse aerial hyphae and a slight salmon color in the conidial masses. Pycnidia produced on OA were globose to subglobose, usually with one slightly ostiolar papilla, olivaceous to olivaceous black, and 93 to 245 μm in diameter. Conidia were hyaline, unicellular, ellipsoidal, mostly with two polar guttules, and 3.6 to 6.2 × 2.0 to 3.3 μm. Chlamydospores were absent. Growth of the isolates on malt extract agar (MEA) was slower than on OA, and the colony diameters at 7 days were 60 to 65 mm. The reactions with 1M NaOH were both positive on OA and MEA where the cultures initially changed to yellow green and gradually turned to red. The pathogen was identified as Phoma bellidis Neerg. based on descriptions in Boerema et al. (2). Pathogenicity tests were performed with the three isolates in the laboratory by spraying conidial suspensions (1 × 106 conidia/ml) containing 0.1% Tween 20 until runoff (30 ml per plant) onto stem surfaces of 50-day-old, 60 cm tall plants. For each isolate, there were 50 stems from five replicate plants that had multiple stems per plant. Control plants were treated with sterilized water containing 0.1% Tween 20 only. Plants were incubated with a 16-h photoperiod at 28°C and 90% relative humidity in an artificial climate chamber. Five days after inoculation, typical red-brown spots were observed on all inoculated stems but no symptoms were seen on water-treated control plants. Koch's postulates were fulfilled by reisolation of P. bellidis from diseased stems. The pathogenicity tests were repeated twice more with the same results. P. bellidis has only been reported previously on Bellis spp. from England, Denmark, Italy, the Netherlands, and Switzerland (1,2). Furthermore, there are only a few fungal diseases known to be associated with E. dulcis, and none so far that involve species of Phoma (3,4). To our knowledge, this is the first report of P. bellidis infecting E. dulcis worldwide. References: (1) M. M. Aveskamp et al. Stud. Mycol. 65:27, 2010. (2) G. H. Boerema et al. Phoma Identification Manual: Differentiation of Specific and Infra-Specific Taxa in Culture. CABI Publishing, Wallingford, UK, 2004. (3) P. L. Lentz. Am. Midl. Nat. 67:184, 1962. (4) L. Pan et al. J. Changjiang Vegetables (in Chinese) 14:10, 2010.
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Spring B, Elrington S, Mai Z, Zheng L, Abu-Yousif A, Hasan T. Quantitative, multi-scale fluorescence imaging reveals rapid tumor permeation and intracellular delivery of liposome-associated bevacizumab. Photodiagnosis Photodyn Ther 2011. [DOI: 10.1016/j.pdpdt.2011.03.243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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319
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Chen S, Zheng L, Liu J, Li J, Zhang L, Gu J, Li X, Shen W, Ma F, Yao Y, Wu G, Chen Q. Effects of realgar (tetra-arsenic tetra-sulfide) on malignant tumor cells. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.e13525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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320
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Li J, Qin S, Xu J, Guo WJ, Xiong JP, Bai Y, Sun G, Yang Y, Wang L, Xu N, Cheng Y, Zhe-Hai W, Zheng L, Tao M. A randomized, double-blind, multicenter, phase II, three-arm, placebo-control study of apatinib as third-line treatment in patients with metastatic gastric carcinoma. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.4019] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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321
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Azad NS, Diaz LA, Devoe CE, Laheru D, Le DT, Cosgrove D, Zheng L, De Jesus-Acosta A, Donehower RC, Arlen PM, Bristol JA. A phase I study of NPC-1C, a novel therapeutic antibody to treat pancreas and colorectal cancers. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.tps141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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322
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Liang Z, Guo J, Zhang H, Yang C, Pu J, Mei H, Zheng L, Tong Q. Lymphatic sparing versus lymphatic non-sparing laparoscopic varicocelectomy in children and adolescents: a systematic review and meta-analysis. Eur J Pediatr Surg 2011; 21:147-53. [PMID: 21351044 DOI: 10.1055/s-0031-1271733] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVE The aim of this study was to explore the true efficacy and potential advantages of lymphatic sparing laparoscopic varicocelectomy (LSV) over lymphatic non-sparing laparoscopic varicocelectomy (LNSV) in children and adolescents. METHODS A search was made for studies published up until 31 August 2010 using the terms "lymphatic sparing varicocelectomy", "laparoscopy", "adolescent" and "children" in the Medline, Embase, Ovid, Web of Science, and Cochrane databases. Randomized controlled trials (RCTs) and observational clinical studies (OCSs) comparing LSV and LNSV were included. A systematic review and meta-analysis was performed using odds ratios (ORs) for dichotomous variables. RESULTS Out of 127 studies, 2 RCTs and 4 OCSs were eligible for inclusion, comprising 489 cases of LSV and 307 cases of LNSV. The hydrocele rates after LSV were significantly lower than after LNSV (OR = 0.19; 95% confidence interval [CI] = 0.10 to 0.36; p < 0.00001). However, no significant difference was observed between LSV and LNSV with regard to recurrence (OR = 0.65; 95% CI = 0.32-1.33; p = 0.24) or catch-up growth (OR = 2.14; 95% CI =0.97-4.72; p = 0.06). CONCLUSION LSV is valuable in reducing the incidence of postoperative hydrocele, with similar recurrence and catch-up growth rates as LNSV. A series of RCTs are warranted to explore the efficacy of LSV in the management of varicocele in children and adolescents.
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323
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Zheng L, Tanaka H, Abe S. Proteomic analysis of inviable salmonid hybrids between female masu salmon Oncorhynchus masou masou and male rainbow trout Oncorhynchus mykiss during early embryogenesis. JOURNAL OF FISH BIOLOGY 2011; 78:1508-1528. [PMID: 21539556 DOI: 10.1111/j.1095-8649.2011.02958.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Early embryos of inviable hybrids between female masu salmon Oncorhynchus masou masou and male rainbow trout Oncorhynchus mykiss at 9, 12, 15 and 20 days after fertilization were examined for protein expression profiles. A total of 44 proteins, mostly down-regulated products of house-keeping genes and those involved in nucleic acid metabolism or chromatin replication, were identified in hybrid embryos by mass spectrometry analysis and protein database searching. The identified down-regulated proteins may be responsible for the inviability in the hybrids.
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324
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Zeng J, Zheng L, Sun X, He Q. Application of Cross-Flow Microfiltration for Purifying Solvent Naphtha with Ceramic Membranes. Chem Eng Technol 2011. [DOI: 10.1002/ceat.201000493] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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325
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Zheng L, Lv R, Li Q, Huang J, Wang Y, Hsiang T. First Report of Leaf Spot of Houttuynia cordata Caused by Alternaria alternata in China. PLANT DISEASE 2011; 95:359. [PMID: 30743519 DOI: 10.1094/pdis-10-10-0724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Houttuynia cordata is a perennial herbaceous plant (family Saururaceae) that is native to southern China, Japan, Korea, and Southeast Asia where it grows well in moist to wet soils. It is commonly used as a Chinese herbal medicine and as a vegetable. In North America and Europe it is also used as an ornamental. From September 2007 to November 2009, symptoms of leaf spot were found on H. cordata leaves in Dangyang County, Hubei, China, with the crop area affected estimated to be over 600 ha per year. Rhizome yield was reduced by 20% on average, with up to 70% yield losses in some fields during the autumn growing season. Lesions were initially small, brown, and oval or circular that developed into dark spots and sometimes formed target spots with white centers. These spots enlarged and overlapped, extending until the leaves withered entirely usually within 2 months. A fungus was consistently recovered from symptomatic leaf samples collected in October 2008 or 2009 with an average 90% isolation rate from ~60 leaf pieces that were surface sterilized with 0.1% mercuric chloride solution. Three isolates, HCDY-2, HCDY-3, and HCDY-4, were used to further evaluate characteristics of the pathogen. On potato dextrose agar, all cultures initially developed white colonies and the centers turned gray or brown after 4 days of incubation. Conidiophores were single or fasciculate, straight or knee curved, gray-brown with regular septa, and 42 to 61 × 4 to 5 μm. Conidia were obclavate or ovate, brown, and 26 to 38 × 12 to 20 μm with three to five transverse and one to three longitudinal or oblique septa. The tops of some conidia developed into secondary conidiophores, which were cylindrical, beige, and 5 to 17 × 3 to 5 μm. The pathogen was identified as Alternaria alternata based on descriptions in Simmons (3). Genomic DNA of HCDY-2 was extracted, and the rDNA-internal transcribed spacer sequence showed 99.6% identity to A. alternata (GenBank No. AY513941). Pathogenicity tests were performed with the three isolates by spraying conidial suspensions (1 × 106 conidia/ml) containing 0.1% Tween 20 onto upper and lower surfaces of leaves of 40-day-old 15-cm high plants. There were 20 leaves from five replicate plants for each isolate. Control plants were treated with sterilized water containing 0.1% Tween 20 only. All plants were incubated with a 16-h photoperiod at 25°C and 90% relative humidity in an artificial climate chamber. Five days after inoculation, typical brown spots were observed on all inoculated leaves but no symptoms were seen on water-treated control plants. Koch's postulates were fulfilled by reisolation of A. alternata from diseased leaves. The pathogenicity tests were carried out twice. A survey of the literature revealed only a few fungal diseases associated with H. cordata (1,2,4), including Phyllosticta houttuyniae, Pseudocercospora houttuyniae, Rhizoctonia solani, and Sclerotium rolfsii. Although A. alternata is a cosmopolitan plant pathogen, it has not been reported on any species in the four genera in Saururaceae (Anemopsis, Gymnotheca, Houttuynia, and Saururus) (3). To our knowledge, this is the first report of A. alternata infecting H. cordata worldwide. References: (1) Y. L. Guo and W. X. Zhao. Acta Mycol. Sin. 8:118, 1989. (2) K. Sawada. Spec. Publ. Taiwan Univ. 8:138, 1959. (3) E. G. Simmons. Alternaria: An Identification Manual. The American Phytopathological Society, St. Paul, MN, 2007. (4) Y. Wu et al. J. Changjiang Vegetables (In Chinese) 2:19, 2007.
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