[The efficacy and safety of laparoscopic radical gastrectomy after neoadjuvant chemotherapy combined with immunotherapy and targeted therapy]

Objectives: To explore the efficacy and safety of laparoscopic radical gastrectomy after neoadjuvant chemotherapy combined with immunotherapy and targeted therapy in patients with gastric cancer. Methods: A retrospective analysis of clinical and pathological data of 20 patients with locally advanced gastric cancer (clinical TNM stage T3-4aN+M0) admitted to the Cancer Hospital, Chinese Academy of Medical Sciences from July 2021 to July 2023. All patients received 3 cycles of SOX (Oxaliplatin+S-1) regimen combined with immunotherapy (Trastuzumab) and targeted therapy (Apatinib) as neoadjuvant treatment followed by laparoscopic radical gastrectomy for gastric cancer. Surgical outcomes, postoperative pathological response, and postoperative recovery were observed. Quantitative data, except for age and operation time, were expressed using Median (range). Results: Among the 20 patients, there were 18 males and 2 females, aged 41 to 73 years [(60.6±9.7) years]. All 20 patients underwent laparoscopic surgical treatment after neoadjuvant therapy, with one patient undergoing laparoscopic conversion to open total gastrectomy with partial transverse colon resection due to tumor invasion into the transverse mesocolon. Eight patients underwent totally laparoscopic radical gastrectomy, all with Billroth Ⅱ+Braun anastomosis at the distal stomach. Eleven patients underwent laparoscopic-assisted radical gastrectomy, among which total gastrectomy with Roux-en-Y anastomosis was performed in ten cases, and proximal gastrectomy with esophagogastrostomy overlap anastomosis was performed in one case. The mean operation time for the 20 patients was (165.0±34.1) minutes; intraoperative blood loss was 80 (20-100) ml; and the number of lymph nodes retrieved was 68 (21-89). Postoperative pathological TNM staging revealed stage T0N0M0 in six cases, stage Ⅰ in two cases, stage Ⅱ in three cases, and stage Ⅲ in nine cases. Six patients (30.0%) achieved pathological complete response, and nine patients (45.0%) achieved significant pathological response. The median postoperative time to flatus was 4 (1-5) days; oral intake resumed after 3 (2-5) days; and the median length of hospital stay was 13 (6-19) days. One patient developed colonic anastomotic leakage with intra-abdominal infection, and one patient developed duodenal stump leakage with intra-abdominal infection, both classified as Clavien-Dindo grade 3A complications, and improved after treatment and discharged. One patient developed gastric paresis, and two patients developed pleural effusion, classified as Clavien-Dindo grade 2 complications, and improved after treatment and discharged. There were no deaths within 30 days after discharge. Conclusions: Laparoscopic radical gastrectomy for gastric cancer after neoadjuvant treatment with the SOX regimen combined with immunotherapy and targeted therapy is safe and feasible, with satisfactory short-term efficacy. However, there is an increase in overall surgical risk and difficulty, and it is recommended to be performed in experienced gastric cancer centers.

Amplitude Analysis of the B^{0}→K^{*0}μ^{+}μ^{-} Decay

An amplitude analysis of the B^{0}→K^{*0}μ^{+}μ^{-} decay is presented using a dataset corresponding to an integrated luminosity of 4.7  fb^{-1} of pp collision data collected with the LHCb experiment. For the first time, the coefficients associated to short-distance physics effects, sensitive to processes beyond the standard model, are extracted directly from the data through a q^{2}-unbinned amplitude analysis, where q^{2} is the μ^{+}μ^{-} invariant mass squared. Long-distance contributions, which originate from nonfactorizable QCD processes, are systematically investigated, and the most accurate assessment to date of their impact on the physical observables is obtained. The pattern of measured corrections to the short-distance couplings is found to be consistent with previous analyses of b- to s-quark transitions, with the largest discrepancy from the standard model predictions found to be at the level of 1.8 standard deviations. The global significance of the observed differences in the decay is 1.4 standard deviations.

Fraction of χ_{c} Decays in Prompt J/ψ Production Measured in pPb Collisions at sqrt[s_{NN}]=8.16 TeV

The fraction of χ_{c1} and χ_{c2} decays in the prompt J/ψ yield, F_{χ_{c}→J/ψ}=σ_{χ_{c}→J/ψ}/σ_{J/ψ}, is measured by the LHCb detector in pPb collisions at sqrt[s_{NN}]=8.16  TeV. The study covers the forward (1.5 Collapse

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Observation of Cabibbo-Suppressed Two-Body Hadronic Decays and Precision Mass Measurement of the Ω_{c}^{0} Baryon

The first observation of the singly Cabibbo-suppressed Ω_{c}^{0}→Ω^{-}K^{+} and Ω_{c}^{0}→Ξ^{-}π^{+} decays is reported, using proton-proton collision data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4  fb^{-1}, collected with the LHCb detector between 2016 and 2018. The branching fraction ratios are measured to be B(Ω_{c}^{0}→Ω^{-}K^{+})/B(Ω_{c}^{0}→Ω^{-}π^{+})=[6.08±0.51(stat)±0.40(syst)]%,B(Ω_{c}^{0}→Ξ^{-}π^{+})/B(Ω_{c}^{0}→Ω^{-}π^{+})=[15.81±0.87(stat)±0.44(syst)±0.16(ext)]%. In addition, using the Ω_{c}^{0}→Ω^{-}π^{+} decay channel, the Ω_{c}^{0} baryon mass is measured to be M(Ω_{c}^{0})=2695.28±0.07(stat)±0.27(syst)±0.30(ext)  MeV, improving the precision of the previous world average by a factor of 4.

Enhanced Production of Λ_{b}^{0} Baryons in High-Multiplicity pp Collisions at sqrt[s]=13 TeV

The production rate of Λ_{b}^{0} baryons relative to B^{0} mesons in pp collisions at a center-of-mass energy sqrt[s]=13  TeV is measured by the LHCb experiment. The ratio of Λ_{b}^{0} to B^{0} production cross sections shows a significant dependence on both the transverse momentum and the measured charged-particle multiplicity. At low multiplicity, the ratio measured at LHCb is consistent with the value measured in e^{+}e^{-} collisions, and increases by a factor of ∼2 with increasing multiplicity. At relatively low transverse momentum, the ratio of Λ_{b}^{0} to B^{0} cross sections is higher than what is measured in e^{+}e^{-} collisions, but converges with the e^{+}e^{-} ratio as the momentum increases. These results imply that the evolution of heavy b quarks into final-state hadrons is influenced by the density of the hadronic environment produced in the collision. Comparisons with several models and implications for the mechanisms enforcing quark confinement are discussed.

Improved Measurement of CP Violation Parameters in B_{s}^{0}→J/ψK^{+}K^{-} Decays in the Vicinity of the ϕ(1020) Resonance

The decay-time-dependent CP asymmetry in B_{s}^{0}→J/ψ(→μ^{+}μ^{-})K^{+}K^{-} decays is measured using proton-proton collision data, corresponding to an integrated luminosity of 6  fb^{-1}, collected with the LHCb detector at a center-of-mass energy of 13 TeV. Using a sample of approximately 349 000 B_{s}^{0} signal decays with an invariant K^{+}K^{-} mass in the vicinity of the ϕ(1020) resonance, the CP-violating phase ϕ_{s} is measured, along with the difference in decay widths of the light and heavy mass eigenstates of the B_{s}^{0}-B[over ¯]_{s}^{0} system, ΔΓ_{s}, and the difference of the average B_{s}^{0} and B^{0} meson decay widths, Γ_{s}-Γ_{d}. The values obtained are ϕ_{s}=-0.039±0.022±0.006  rad, ΔΓ_{s}=0.0845±0.0044±0.0024  ps^{-1}, and Γ_{s}-Γ_{d}=-0.0056_{-0.0015}^{+0.0013}±0.0014  ps^{-1}, where the first uncertainty is statistical and the second systematic. These are the most precise single measurements to date and are consistent with expectations based on the Standard Model and with the previous LHCb analyses of this decay. These results are combined with previous independent LHCb measurements. The phase ϕ_{s} is also measured independently for each polarization state of the K^{+}K^{-} system and shows no evidence for polarization dependence.

Measurement of CP Violation in B^{0}→ψ(→ℓ^{+}ℓ^{-})K_{S}^{0}(→π^{+}π^{-}) Decays

A measurement of time-dependent CP violation in the decays of B^{0} and B[over ¯]^{0} mesons to the final states J/ψ(→μ^{+}μ^{-})K_{S}^{0}, ψ(2S)(→μ^{+}μ^{-})K_{S}^{0} and J/ψ(→e^{+}e^{-})K_{S}^{0} with K_{S}^{0}→π^{+}π^{-} is presented. The data correspond to an integrated luminosity of 6  fb^{-1} collected at a center-of-mass energy of sqrt[s]=13  TeV with the LHCb detector. The CP-violation parameters are measured to be S_{ψK_{S}^{0}}=0.717±0.013(stat)±0.008(syst) and C_{ψK_{S}^{0}}=0.008±0.012(stat)±0.003(syst). This measurement of S_{ψK_{S}^{0}} represents the most precise single measurement of the CKM angle β to date and is more precise than the current world average. In addition, measurements of the CP-violation parameters of the individual channels are reported and a combination with the LHCb Run 1 measurements is performed.

[Analysis of iodine nutritional status of children aged 8-10 years in Zhejiang Province from 2016 to 2021]

Objective: To analyze the iodine nutrition status of children aged 8 to 10 years in Zhejiang Province from 2016 to 2021. Methods: A multi-stage stratified sampling method was used to select non-residential children aged 8 to 10 years from 90 counties in Zhejiang Province. A total of 114 103 children were included in the study from 2016 to 2021. Direct titration method and arsenic-cerium catalytic spectrophotometry were used to detect salt iodine content and urinary iodine level, respectively, to evaluate the iodine nutritional status of children. Ultrasound was used to detect thyroid volume and analyze the current prevalence of goiter in school-age children. Results: The age of 114 103 children was (9.04 ± 0.81) years old, with 50.0% of (57 083) boys. The median of iodine content M (Q1, Q3) in children's household salt was 23.00 (19.80, 25.20) mg/kg, including 17 242 non-iodized salt, 6 173 unqualified iodized salt, and 90 688 qualified iodized salt. The coverage rate of iodized salt was 84.89%, and the coverage rate of qualified iodized salt was 79.48%. The proportion of non-iodized salt increased from 11.85% in 2016 to 16.04% in 2021 (χ2trend=111.427, P<0.001). The median of urinary iodine concentration M (Q1, Q3) in children was 182.50 (121.00, 261.00) μg/L, among which the proportions of iodine deficiency, iodine suitability, iodine over suitability, and iodine excess were 17.25% (19 686 cases), 39.21% (44 745 cases), 26.85% (30 638 cases), and 16.68% (19 034 cases), respectively. The median of urinary iodine concentration in children in inland areas [M (Q1, Q3): 190.90 (128.80, 269.00) μg/L] was significantly higher than that in children in coastal areas [M (Q1, Q3): 173.00 (113.00, 250.30) μg/L] (P<0.001). From 2016 to 2021, a total of 39 134 ultrasound examinations were conducted, and 1 229 cases of thyroid enlargement were detected. The goiter rate was 3.14% (95%CI: 2.97%-3.32%). The incidence of goiter in children in coastal areas [3.45% (95%CI: 3.19%-3.72%), 641/18 604] was higher than that in children in inland areas [2.86% (95%CI: 2.64%-3.10%), 588/20 530] (P=0.001). Conclusion: From 2016 to 2021, the iodine nutrition level of children aged 8-10 years in Zhejiang Province is generally suitable, and the rate of goiter in children meets the limit of iodine deficiency disease elimination standards.

[Pathological significance of plasma cell infiltration in diagnosing lymph node diseases]

Objective: To investigate the value of plasma cells for diagnosing lymph node diseases. Methods: Common lymphadenopathy (except plasma cell neoplasms) diagnosed from September 2012 to August 2022 were selected from the pathological records of Changhai Hospital, Shanghai, China. Morphological and immunohistochemical features were analyzed to examine the infiltration pattern, clonality, and IgG and IgG4 expression of plasma cells in these lymphadenopathies, and to summarize the differential diagnoses of plasma cell infiltration in common lymphadenopathies. Results: A total of 236 cases of lymphadenopathies with various degrees of plasma cell infiltration were included in the study. There were 58 cases of Castleman's disease, 55 cases of IgG4-related lymphadenopathy, 14 cases of syphilitic lymphadenitis, 2 cases of rheumatoid lymphadenitis, 18 cases of Rosai-Dorfman disease, 23 cases of Kimura's disease, 13 cases of dermal lymphadenitis and 53 cases of angioimmunoblastic T-cell lymphoma (AITL). The main features of these lymphadenopathies were lymph node enlargement with various degrees of plasm cell infiltration. A panel of immunohistochemical antibodies were used to examine the distribution of plasma cells and the expression of IgG and IgG4. The presence of lymph node architecture could help determine benign and malignant lesions. The preliminary classification of these lymphadenopathies was based on the infiltration features of plasma cells. The evaluation of IgG and IgG4 as a routine means could exclude the lymph nodes involvement of IgG4-related dieases (IgG4-RD), and whether it was accompanied by autoimmune diseases or multiple-organ diseases, which were of critical evidence for the differential diagnosis. For common lesions of lymphadenopathies, such as Castleman's disease, Kimura's disease, Rosai-Dorfman's disease and dermal lymphadenitis, the expression ratio of IgG4/IgG (>40%) as detected using immunhistochemistry and serum IgG4 levels should be considered as a standard for the possibility of IgG4-RD. The differential diagnosis of multicentric Castleman's diseases and IgG4-RD should be also considered. Conclusions: Infiltration of plasma cells and IgG4-positive plasma cells may be detected in some types of lymphadenopathies and lymphomas in clinicopathological daily practice, but not all of them are related to IgG4-RD. It should be emphasized that the characteristics of plasma cell infiltration and the ratio of IgG4/IgG (>40%) should be considered for further differential diagnosis and avoiding misclassification of lymphadenopathies.

Taxifolin blocks monosodium urate crystal-induced gouty inflammation by regulating phagocytosis and autophagy

Gout is a chronic disease caused by monosodium urate (MSU) crystal deposition in the joints and surrounding tissues. We examined the effects of Taxifolin, a natural flavonoid mainly existing in vegetables and fruits, on MSU-induced gout. Pretreatment with Taxifolin significantly reduced IL-1β, Caspase-1 and HMGB1 levels, upregulation of autophagy-related protein, LC3, as well as improved phagocytosis of macrophages. This study indicated that Taxifolin-attenuated inflammatory response in MSU-induced acute gout model by decreasing pro-inflammatory cytokine production and promoting the autophagy and phagocytic capacity of macrophages. Dietary supplementation with Taxifolin induces the autophagy and attenuated inflammatory response, which in consequence modulates acute gout. A preventive strategy combining dietary interventions with Taxifolin may offer a potential therapeutic alternative to pharmacological treatment to reduce inflammatory response to gout.

[Long-term observation of the effect of atlantoaxial fusion on the growth and development of children's cervical spine]

Objective: To explore the effect of atlantoaxial fusion on the growth and development of children's cervical spine. Methods: The clinical data of 12 children with atlantoaxial dislocation who underwent posterior atlantoaxial fusion at Department of Orthopaedics,the 909th Hospital of Joint Logistics Support Force of Chinese People's Liberation Army from June 2002 to September 2013 were retrospective analyzed. There were 7 males and 5 females,with age of (8.1±3.1)years (range:3 to 13 years).Nine cases were traumatic and 3 cases were congenital malformations,1 of the children had Down syndrome. All children underwent posterior atlantoaxial fusion. Furthermore,the information of the height and anteroposterior width of the cervical vertebral bodies and vertical growth rate of the fusion mass were collected from all patients immediately postoperatively and during the follow-up.The range of motion in cervical spine were collected preoperatively and during follow-up period. Data were compared using independent sample t test, paired sample t test and repeated-measurement. Results: All 12 children had regular follow-up within (122.4±25.3)months(range:65 to 163 months). The height and anteroposterior width of the cervical vertebral bodies were similar to these results with those in published reports of growth in normal children of the same age(all P<0.01). At the last follow-up,atlantoaxial fusion of 11 cases had substantial growth (vertical growth rate of the fusion mass:11 cases ≥10%, 1 case <10%);the range of motion in cervical spine was close to the normal level (flexion(55.2±5.0)°,extension (65.3±4.9)°,left bending (41.7±4.5)°,right bending (42.4±4.4)°,left rotation (66.4±5.6)°,right rotation (68.5±5.8)°). Conclusions: Atlantoaxial fusion surgery is satisfactory in the treatment of pediatric atlantoaxial dislocation.During the follow-up,the growth and development of the cervical spine is close to that of normal children of the same age.In long-term observation,it has been found that the operation has no negative effect on the growth and development of the children's cervical spine.

Docosahexaenoic Acid Reverses Epithelial-Mesenchymal Transition and Drug Resistance by Impairing the PI3K/AKT/ Nrf2/GPX4 Signalling Pathway in Docetaxel-Resistant PC3 Prostate Cancer Cells

Drug resistance is a serious problem in cancer therapy. Growing evidence has shown that docosahexaenoic acid has anti-inflammatory and chemopreventive abilities. Studies have shown that autophagy inhibition and ferroptosis are promising therapeutic strategies for overcoming multidrug resistance. This study was aimed to examine whether docosahexaenoic acid (DHA) could reverse docetaxel resistance in prostate cancer cells. Cell survival was examined by MTT and colony formation. Protein expression was determined by Western blot. Reactive oxygen species (ROS) production was measured by flow cytometry. DHA displayed anti-cancer effects on proliferation, colony formation, migration, apoptosis, autophagy and epithelial mesenchymal transition. Glutathione-S-transferase π is an enzyme that plays an important role in drug resistance. DHA inhibited GSTπ protein expression and induced cytoprotective autophagy by regulating the PI3K/AKT signalling pathway in PC3R cells. DHA combined with PI3K inhibitor (LY294002) enhanced apoptosis by alleviating the expression of LC3B, (pro-) caspase- 3 and (uncleaved) PARP. DHA induced ferroptosis by attenuating the expression of glutathione peroxidase 4 (GPX4) and nuclear erythroid 2-related factor 2 (Nrf2). DHA-treated PC3R cells produced ROS. The ROS and cytotoxicity were reversed by treatment with ferrostatin-1. DHA combined with docetaxel inhibited EMT by regulating the expression of E-cadhein and N-cadherin. In summary, DHA reversed drug resistance and induced cytoprotective autophagy and ferroptosis by regulating the PI3K/AKT/Nrf2/GPX4 signalling pathway in PC3R cells. We propose that DHA could be developed as a chemosensitizer and that the PI3K/AKT /Nrf2/GPX4 signalling pathway might be a promising therapeutic target for overcoming cancer drug resistance.

Three first records of stick insects attacking plants (Inseect: Phasmida) in Tibet

Except for a few stick insects that are economically valuable, most species be considered to be forest pests, so it is extremely important to obtain plant host-use information of more stick insects. In this paper, the plant hosts of three species of stick insects were recorded for the first time. We also discovered these stick insects can feed upon the flowers or leaves of plants. Lopaphus unidentatus (Chen & He, 1995) (Phasmida: Lonchodidae) attacked Hypericum choisianum Wall. ex N. Robson, 1973 (Hypericaceae), Leurophasma dolichocercum Bi, 1995 (Phasmida: Aschiphasmatidae) attacked Antenoron filiforme (Thunb.) Roberty & Vautier, 1964 (Polygonaceae) and Megalophasma granulatum Bi, 1995 (Phasmida: Lonchodidae) attacked Debregeasia orientalis C. J. Chen, 1991 (Urticaceae). Finally, we were lucky enough to also obtain photographs of them mating and feeding.

[HIV self-testing reagent use in pre-exposure prophylaxis and related factors in men who have sex with men]

Objective: To understand the current status of HIV self-testing reagent use in pre-exposure prophylaxis (PrEP) and related factors in men who have sex with men (MSM). Methods: From December 2018 to December 2019, "Gold data" online platform (www.jinshuju.com) was used to conduct multicenter PrEP studies in Shenyang, Beijing, Chongqing and Shenzhen of China. Results: A total of 1 222 MSM PrEP users were included in the multicenter study. The average age of the participants was (31.5±8.7) years, and the number of sexual partners in the past three months was 3 (P₂₅,P₇₅:2,6). The proportions of those who did not use condoms in anal sex with fixed, casual and commercial partners were 62.7% (456/727), 56.3% (440/781) and 41.0% (16/39), respectively. Up to 74.5% (910/1 222) of participants had used HIV self-testing reagents, and the number of HIV self-testing during last year was 3 (P₂₅,P₇₅:2,5). The multivariate logistic regression analysis indicated that compared with age group >40 years, those with education level of junior high school or below, those with psychological identity as female, event driven PrEP users, those never using new type drugs in past 3 months, the participants aged 18- years (aOR=2.06, 95%CI: 1.35-3.14), 26- years (aOR=2.72, 95%CI: 1.77-4.17), 31- years (aOR=1.76, 95%CI: 1.19-2.59), undergraduates (aOR=2.18, 95%CI: 1.35-3.49), graduate students and above (aOR=3.06, 95%CI: 1.69-5.54), those with psychological identity as male (aOR=3.22, 95%CI: 1.55-6.70), daily PrEP users (aOR=1.35, 95%CI: 1.03-1.78), and new type drug users in the past three months (aOR=1.72, 95%CI: 1.30-2.28) had higher proportions of HIV self-testing behaviors. Conclusions: The proportion of HIV self-testing in MSM PrEP users was high, while it was relatively low in older age group, event driven PrEP users and MSM never using new type drugs. To assess and improve the effectiveness and compliance of PrEPs, it is necessary to provide better HIV self-testing service for MSM with low HIV self-testing rate.

[Bioinformatics analysis of key genes and prognosis-related genes during the onset of hepatocellular carcinoma]

Objective: To screen and analyze the differentially-expressed genes (DEGs) in primary hepatocellular carcinoma tissues and adjacent tissues using bioinformatics methods to explore the molecular mechanism of the occurrence and prognosis of primary hepatocellular carcinoma. Methods: GSE76427 data set was collected through GEO database, and DEGs were identified using GEO2R online analysis. Go and KEGG databases were used for enrichment and functional annotation of DEGs. Protein interaction network was built based on the STRING database and Cytoscape software to analyze the key genes of hepatocellular carcinoma, and the survival curve of these key genes were analyzed using the GEPIA database. Results: A total of 74 hepatocellular carcinoma DEGs were screened, of which 3 and 71 were up-and-down-regulated genes. The results of GO enrichment analysis showed that the down-regulated DEGs were mainly involved in cell response to cadmium and zinc ions, negative growth regulation, heterologous metabolic processes and hormone-mediated signaling pathways. KEGG pathway enrichment analysis results showed that the down-regulated DEGs pathway were mainly involved in retinol metabolism, chemical carcinogenesis, drug metabolism-cytochrome P450, cytochrome P450 metabolizing xenobiotics, tryptophan metabolism and caffeine metabolism. Protein interaction network had screened out 10 down-regulated core genes: MT1G, MT1F, MT1X, MT1E, MT1H, insulin-like growth factor 1, FOS, CXCL12, EGR1, and BGN. Among them, the insulin-like growth factor 1 was related to the prognosis of primary hepatocellular carcinoma. Conclusion: Bioinformatics analysis results of HCC chip data showed that 10 key genes may play a key role in the occurrence and development of HCC and the insulin like growth factor 1 is associated with the prognosis of primary hepatocellular carcinoma.

[Integrated analysis of DNA methylation and gene expression profiles of hepatocellular carcinoma to construct miR-1180-3p relevant ceRNA regulatory network]

Objective: This study analyzes the expression level of miR-1180-3p and constructs the regulatory network of relevant ceRNA by integrating the DNA methylation and gene expression profile of hepatocellular carcinoma from the Cancer Genome Atlas (TCGA). Methods: Firstly, the expression level of miR-1180-3p in hepatocellular carcinoma and adjacent tissues was analyzed by TCGA database, and the differential expression of lncrna and mRNA was screened. Secondly, the LncBase database and the TargetScan database were used to predict the relationship between miR-1180-3p and lncRNA and mRNA, and the DNA methylation-mediated lncRNA was screened by the DNA methylation profile of lncRNA. Finally, Cytoscape software was used to construct miR-1180-3p relevant ceRNA network, and WebGestalt website was used to perform GO and KEGG analysis of related mRNA in ceRNA. Results: Compared with patients with low expression of miR-1180-3p (mean overall survival duration, 5.69 ± 0.35 years), patients with high expression of miR-1180-3p had shorter overall survival time (mean overall survival duration, 3.99 ± 0.47 years), indicating that the high expression of miR-1180-3p was hepatocellular carcinoma risk factor affecting the prognosis (HR = 1.28, 95% CI = 1.1 ~ 1.5, P < 0.01). A miR-1180-3p related ceRNA regulatory network was constructed in this study, which contained 2 lncRNAs (F11-AS1 and LINC01511) and 37 mRNAs. Conclusion: This study has successfully constructed miR-1180-3p relevant ceRNA regulatory network, and DNA methylation-mediated F11-AS1 and F11-AS1/miR-1180-3p/C11of54 ceRNA regulatory axis has played an important role in the occurrence and development of hepatocellular carcinoma.

[Systematic review of physical and psychosocial problems of burned children aged 5 years and below after discharge]

Objective: To summarize the physical and psychosocial problems of burned children aged 0 to 5 years so as to explore their demands of care after discharge. Methods: Databases including Embase, PubMed, PsycARTICLES, and CINAHL Complete were searched using key words " child(*,) infant(*,) toddler, preschool, kid, baby, junior, burn, scald, empyrosis, nursing, care" , and Chinese Journals Full-text Database, China Biology Medicine disc, and VIP Database were searched using key words in Chinese version ",,,,,,,," to obtain the articles about physical and psychosocial health-related problems of burned children aged 0 to 5 years after discharge from the establishment of each database to February 2018. After screening of extracted articles, the physical and psychosocial problems of burned children aged 0 to 5 years after discharge and psychosocial problems of their caregivers were summarized. Results: (1) A total of 3 880 articles were obtained, after screening layer by layer, 9 English articles were finally included, including 4 prospective observational studies, 3 cross-sectional studies, 1 cohort study, and 1 case-control study, with 1 high-quality literature and 8 medium-quality literatures. (2) After discharge, burned children aged 0 to 5 years mainly had physical problems such as pain, itching, fine motor developmental disorders, and gross motor developmental disorders. They had psychosocial problems such as negative emotional behavior, delayed language development, affected game interaction, post-traumatic stress disorder (PTSD), and disrupted family life. The caregivers had psychosocial problems such as worrying about the appearance and the future of children, dissatisfaction with the current status of children, anxiety and depression, pain, and PTSD. The influencing factors of the above health problems were post-discharge time, post-injury time, total burn area, and burn site, etc. There were 12 kinds of measuring tools used in this group to evaluate the health problems of burned children and psychosocial problems of their caregivers. Only the burn outcomes questionnaire for children aged 0 to 5 years was developed for burned children aged 0 to 5 years. Conclusions: After discharge, burned children aged 0 to 5 years still face many physical and psychosocial problems, which are influenced by factors such as post-discharge time, post-injury time, total burn area and burn site, which suggests that there are certain care needs for them. Appropriate tools for evaluating the health problems of burned children aged 0 to 5 years should be developed.

Correlation between the pathogenesis of bronchial asthma and serum expressions of IL-4, IL-12, IL-37 and 25-(OH)D

Wheezing is a common symptom of respiratory diseases. A survey found that about 1/3 of all children had at least one episode of wheezing before reaching the age of 3, and about 1/2 of them had at least one episode of wheezing by the age of 6.

[Acceptability of pre-exposure HIV prophylaxis clinical trial among MSM in Shenyang city]

Objective: To investigate the acceptability and related factors of an "on-demand" pre-exposure prophylaxis (PrEP) to prevent HIV transmission among MSM in Shenyang. Methods: MSM recruited by non-probability sampling method and questionnaire survey conducted by investigators to collect information on social and behavioral characteristics, awareness of PrEP, Truvada and the acceptability of two different PrEP-based trials. Multivariate logistic regression was employed for statistical analysis. Results: Among the 292 respondents, 34.2% had heard of PrEP and 58.2% (170/292) reported were interested in participating a PrEP trial- "on-demand" use or 48.3% (141/292) interested on "daily" use (χ(2)=5.785, P=0.02). Factors independently associated with those "on-demand" would include: having more than 2 male sexual partners during the past 6 month (aOR=1.7, 95%CI: 1.1-2.7), concerning on the positive effect of PrEP (vs. side effects) (aOR=6.4, 95%CI:2.2-18.9), having an HIV-infected sexual partners (aOR=8.1, 95%CI: 1.0-63.3) and self-reported high risk for HIV (aOR=2.6, 95%CI: 1.2-6.0). The last two factors were only associated with the "on-demand" group. Conclusions: "On-demand" PrEP (as opposed to daily) seemed a more feasible prevention strategy on HIV and particularly in those having high risk behavior of HIV. For those who could not follow the daily medication or having HIV risk perception, "On-demand" basis PrEP trial should be recommended for them to follow.

[Bibliometric analysis on research hotspots on HIV post-exposure prophylaxis related articles in the world, 2000-2017]

Objective: To analyze and reveal the distribution, research hotspots and study trend of worldwide published articles correlated with HIV/AIDS post-exposure prophylaxis (PEP), and provide information for related studies in China. Methods: CiteSpace software 5.1 was used to visualize all related papers in the web of science database published during 2000-2017. Results: The average growth rate of international PEP-related papers was 10.78%,and number of published papers in 2016 was highest (n=34), relevant research hotspots have shifted from the prevention of occupational HIV exposure to the prevention of non-occupational HIV exposure in group at high risk, such as MSM, in recent years. Clustering analysis classified research hotspots into three categories, including risk reduction through enhanced intervention, current status of global HIV PEP and German-Austrian Recommendation. Conclusions: Non-occupational HIV PEP in groups at high-risk, especially MSM, has received increasing attention in recent years, the research of PEP mainly focus on improving the awareness and use of PEP in MSM and compliance in the course of medication. In the context of severe HIV epidemic in MSM without effective control in China, PEP should be strengthened to assess and explore the risk of HIV infection in MSM to provide reference for medical personnel and related departments to implement HIV non-occupation exposure blockade and formulate PEP medication.

[Ventilator-associated pneumonia among premature infants <34 weeks' gestational age in neonatal intensive care unit in China: a multicenter study]

Objective: To investigate the incidence and pathogen distribution of ventilator-associated pneumonia (VAP) among preterm infants admitted to level Ⅲ neonatal intensive care units (NICU) in China. Method: A prospective study was conducted in 25 level Ⅲ NICU, enrolling all preterm infants <34 weeks gestational age admitted to the participating NICU within the first 7 days of life from May 2015 to April 2016. Chi-square test, t test and Mann-Whitney U test were used for statistical analysis. Result: A total of 7 918 patients were enrolled, within whom 4 623(58.4%) were males. The birth weight was (1 639±415) g and the gestational age was (31.4±2.0) weeks; 4 654(58.8%) infants required non-invasive mechanical ventilation and 2 154(27.2%) required intubation. Of all the mechanically ventilated patients, VAP occurred in 95 patients. The overall VAP rate was 7.0 episodes per 1 000 ventilator days, varying from 0 to 34.4 episodes per 1 000 ventilator days in different centers. The incidence of VAP was 9.6 and 6.0 per 1 000 ventilator days in children's hospitals and maternity-infant hospitals respectively, without significant differences (t=1.002, P=0.327). Gram-negative bacilli (76 strains, 91.6%) were the primary VAP microorganisms, mainly Acinetobacter baumannii (24 strains, 28.9%), Klebsiella pneumonia (23 strains, 27.7%), and Pseudomonas aeruginosa (10 strains, 12.0%). Conclusion: The incidence of VAP in China is similar to that in developed counties, with substantial variability in different NICU settings. More efforts are needed to monitor and evaluate the preventable factors associated with VAP and conduct interventions that could effectively reduce the occurrence of VAP.

Effects of arsenic supplementation in feed on laying performance, arsenic retention of eggs and organs, biochemical indices and endocrine hormones

1. The primary objective of this experiment was to estimate the toxic effects of arsenic (As) supplementation in feed on laying performance, As retention by eggs and organs, serum biochemical indices and endocrine hormones in laying hens. 2. A total of 320 "Jinghong Number 1" hens, 56-week-old, were randomly allocated into four treatments of four replicates with 20 layers in each. Graded arsenical was added to the basal diet in the experimental diets at As levels of 0, 17, 34 and 51 mg/kg, respectively. The trial lasted for 9 weeks including 1 week for acclimatisation. 3. Supplementation of dietary As for eight weeks had no effect on laying performance. As retention in albumen, yolk, egg, liver and kidney increased as As levels increased The level of serum phosphorus (P) was minimised at the 17 mg As/kg group. The activity of serum glutamic oxaloacetic transaminase (GOT) increased linearly. No differences were observed for levels of serum calcium (Ca), alkaline phosphatase (AKP) and serum glutamic pyruvic transaminase (GPT). Concentrations of estradiol (E₂) and progesterone (PG) declined at 34 and 51 mg/kg As levels compared with the control group. As supplementation exerted no influence on levels of serum follicle stimulating hormone (FSH), luteinising hormone (LH), triiodothyronine (T₃), thyroxine (T₄) and the ratio between T₃ and T₄. 4. In conclusion, dietary As supplementation accelerated retention in tissues and eggs, and affected the laying rate by diminishing hormone levels of E2 and PG at 51 mg/kg.

Evaluation of improved γ-aminobutyric acid production in yogurt using Lactobacillus plantarum NDC75017

Most γ-aminobutyric acid (GABA)-producing microorganisms are lactic acid bacteria (LAB), but the yield of GABA is limited in most of these GABA-producing strains. In this study, the production of GABA was carried out by using Lactobacillus plantarum NDC75017, a strain screened from traditional fermented dairy products in China. Concentrations of substrate (l-monosodium glutamate, L-MSG) and coenzyme (pyridoxal-5-phosphate, PLP) of glutamate decarboxylase (GAD) and culture temperature were investigated to evaluate their effects on GABA yield of Lb. plantarum NDC75017. The results indicated that GABA production was related to GAD activity and biomass of Lb. plantarum NDC75017. Response surface methodology was used to optimize conditions of GABA production. The optimal factors for GABA production were L-MSG at 80 mM, PLP at 18 μM, and a culture temperature of 36 °C. Under these conditions, production of GABA was maximized at 314.56 mg/100 g. Addition of Lb. plantarum NDC75017 to a commercial starter culture led to higher GABA production in fermented yogurt. Flavor and texture of the prepared yogurt and the control yogurt did not differ significantly. Thus, Lb. plantarum NDC75017 has good potential for manufacture of GABA-enriched fermented milk products.

Comparison of the health-related quality of life in patients with narrow gastric tube and whole stomach reconstruction after oncologic esophagectomy: a prospective randomized study

BACKGROUND AND AIMS

To compare the health-related quality of life in patients with narrow gastric tube and whole stomach reconstructions after oncologic esophagectomy.

MATERIAL AND METHODS

In a prospective randomized single-center study from 2007 to 2008, 104 patients underwent esophagectomy for cancer. To assess health-related quality of life, the questionnaire (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 and the Oesophagus-Specific Quality of Life Questionnaire 18) was administered at 3 weeks, 6 months, 1 year, and 2 years after surgery.

RESULTS

The perioperative complication rate was 26.9% in narrow gastric tube group and 48.1% in whole stomach group (P = 0.31). At the time of 3 weeks after surgery, the reflux and dyspnea scores were higher in whole stomach group than in narrow gastric tube group, which meant that the patients in whole stomach group suffered more severe problem. At the time of 6 months and 1 year after surgery, the reflux scores were lower in narrow gastric tube group than in whole stomach group, which revealed that there were less problems of reflux in the patients of narrow gastric tube group; meanwhile, the score of physical function scale in narrow gastric tube group was higher conversely, which suggested that the patients gain a better status in physical function. Nausea and vomiting is the only notable symptom that was worse in whole stomach group at the time of 2 years after surgery, which suggested that patients in whole stomach group suffered more severe nausea and vomiting.

CONCLUSIONS

Narrow gastric tube reconstruction may be a good alternative choice for patients undergoing oncologic esophagectomy in view of better health-related quality of life after the surgery.

Expression of erythropoietin and its receptor in kidneys from normal and cyclosporine-treated rats

Long-term treatment with cyclosporine A (CsA) is associated with various types of complications; however, CsA-induced anemia has not been reported. The present study examined the impact of CsA on hematopoietic parameters and intrarenal expression of erythropoietin (EPO) and the EPO receptor (EPOR) in a rat model of chronic CsA nephrotoxicity. Sprague-Dawley rats were fed a low-salt diet (0.05% sodium) and were treated daily for 4 weeks with vehicle (olive oil 1 mL/kg subcutaneously) or CsA (15 mg/kg subcutaneously). The expression of EPO and EPOR was evaluated by immunohistochemistry and immunoblotting, and hematopoietic parameters were assessed by measuring blood hemoglobin and hematocrit levels, and these variables were compared between treatment groups. Renal function, oxidative stress, histopathology (tubulointerstitial fibrosis), apoptotic cell death, and expression of transforming growth factor β-inducible gene-h3 (βig-h3) were also compared between treatment groups. In kidneys from vehicle-treated rats, endogenous EPO and EPOR protein were expressed constitutively in the outer stripe of the outer medulla and the cortex. EPO protein expression decreased significantly in kidneys from CsA-treated rats. By contrast, EPOR expression was higher in kidneys from CsA-treated rats than in vehicle-treated rats. These changes were accompanied by decreases in serum hemoglobin and hematocrit levels and correlated with the number of cells positive for terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (r = -0.769, P = .003) and βig-h3 protein expression (r = -0.910, P < .001). Long-term treatment with CsA suppresses renal endogenous EPO expression, resulting in anemia. Increases in apoptotic cell death and βig-h3 expression are closely associated with inhibition of EPO expression in chronic CsA nephrotoxicity.

Prevalence of bisexual behaviour among bridge population of men who have sex with men in China: a meta-analysis of observational studies

OBJECTIVE

To integrate the empirical estimates of bisexual behaviour among the bridge population of men who have sex with men (MSM) in China and their HIV and syphilis prevalences stratified by sexual behaviour.

METHODS

The Pubmed, Chinese Biomedical, Chinese National Knowledge Infrastructure, VIP, Wanfang and Google Scholar databases were searched to January 2011 to identify relevant articles. Data of eligible citations were extracted by two reviewers. All analyses were performed using Stata 10.0.

RESULTS

Forty-nine articles (including 28 739 MSM subjects) met the selection criteria. Aggregated findings indicated that the estimated prevalence of bisexual behaviour among MSM in China is 31.2% (95% CI 28.1% to 34.5%). HIV and syphilis prevalences were 5.4% and 11.4%, respectively, among MSM engaging in bisexual behaviour and 3.8% and 9.3% among MSM only having sex with men. HIV prevalence among MSM engaging in sex with both men and women was significantly higher than in those who only have sex with men (OR 1.30; 95% CI 1.04 to 1.62; p=0.02).

CONCLUSION

There is a high prevalence of bisexual behaviour among MSM in China and bisexual behaviour is significantly associated with increased HIV infection risk. The results of this meta-analysis highlight a critical pattern of HIV transmission among MSM in China and indicate that targeted interventions aimed at encouraging safe sex practices and promoting societal and family acceptance of MSM are urgently needed.

Expression and bioactivity analysis of recombinant beta-CPP dimer

Beta-casein phosphopeptide (beta-CPP) is a bioactive peptide that carries different minerals, especially calcium. To investigate more effects of beta-CPP, eukaryotic expression vector of beta-CPP dimer was constructed and transfected into Chinese hamster ovary (CHO) cells. After selection, the cell lines stably expressing beta-CPP dimer were obtained, and the recombinant product was identified and purified. Activity assay of recombinant protein indicated that the recombinant beta-CPP dimer could improve Ca(2+) uptake of sperm, stimulate the proliferation of spleen cells, and induce apoptosis of some malignant tumor cells.

Fgf/MAPK signalling is a crucial positional cue in somite boundary formation

The temporal and spatial regulation of somitogenesis requires a molecular oscillator, the segmentation clock. Through Notch signalling, the oscillation in cells is coordinated and translated into a cyclic wave of expression of hairy-related and other genes. The wave sweeps caudorostrally through the presomitic mesoderm (PSM) and finally arrests at the future segmentation point in the anterior PSM. By experimental manipulation and analyses in zebrafish somitogenesis mutants, we have found a novel component involved in this process. We report that the level of Fgf/MAPK activation (highest in the posterior PSM) serves as a positional cue within the PSM that regulates progression of the cyclic wave and thereby governs the positions of somite boundary formation.

Modulation of cytosolic phospholipase A(2) by PPAR activators in human preadipocytes

Cytosolic phospholipase A(2) (cPLA(2)) is responsible for the release of arachidonic acid, a precursor for eicosanoid biosynthesis, from cellular phospholipids. The objective of this study is to examine the regulation of cPLA(2) by peroxisome proliferator-activated receptor (PPAR) activators in preadipocyte SW872 (SW) cells. PPAR belong to the superfamily of nuclear hormone receptors that heterodimerize with the retinoid X receptor. In this study, the presence of both PPARalpha and PPARgamma was confirmed in SW cells by positive identification of their mRNA in the cellular homogenate. Clofibrate, a PPARalpha activator, caused an enhancement of ionophore A-23187-induced arachidonate release in SW cells. This increase resulted from an enhancement of cPLA(2) activity, which was caused by an increase in enzyme protein. Clofibrate at lower concentrations (10-200 microM) produced increases in the mRNA levels of cPLA(2) in a dose-response manner. At higher concentrations (>400 microM), clofibrate treatment resulted in the attenuation of the cPLA(2) mRNA level and protein expression. We postulate that clofibrate, acting through the PPARalpha, caused an induction in the transcription of cPLA(2) gene, which led to an increase in the cPLA(2) protein. The observed increase in arachidonate release in SW cells appeared to be a direct result of the enhanced cPLA(2) activity.

Notch signalling and the synchronization of the somite segmentation clock

In vertebrates with mutations in the Notch cell-cell communication pathway, segmentation fails: the boundaries demarcating somites, the segments of the embryonic body axis, are absent or irregular. This phenotype has prompted many investigations, but the role of Notch signalling in somitogenesis remains mysterious. Somite patterning is thought to be governed by a "clock-and-wavefront" mechanism: a biochemical oscillator (the segmentation clock) operates in the cells of the presomitic mesoderm, the immature tissue from which the somites are sequentially produced, and a wavefront of maturation sweeps back through this tissue, arresting oscillation and initiating somite differentiation. Cells arrested in different phases of their cycle express different genes, defining the spatially periodic pattern of somites and controlling the physical process of segmentation. Notch signalling, one might think, must be necessary for oscillation, or to organize subsequent events that create the somite boundaries. Here we analyse a set of zebrafish mutants and arrive at a different interpretation: the essential function of Notch signalling in somite segmentation is to keep the oscillations of neighbouring presomitic mesoderm cells synchronized.

Sperm function tests after vasovasostomy

AIM

To evaluate the sperm function after vasovasostomy.

METHODS

Semen samples from 42 subjects after vasovasostomy (Group A: 1-6 months, Group B: 6-12 months; Group C: 12-18 months after vasectomy reversal) were investigated. Semen from 34 normal fertile men was used as controls. Sperm function tests, including hypoosmotic swelling test (HOST), acridine orange (AO) fluorescence, acrosome reaction (triple-stain), cervical mucus penetration test (CMPT), etc were done.

RESULTS

After vasectomy reversal, the percentage of HOST was significantly lower than that of the normal fertile men. In regard to AO, there were no significant differences between the three vasovasostomy groups and between these 3 groups and the controls. With triple-stain, the percentage of normal acrosome reaction was significantly lower in Group A as compared with the controls, but not in Groups B and C. There were no significant differences in the results of CMPT between the vasovasostomy groups and the controls. However, the number of "poor" type was significantly higher in Groups A and C than in the controls; the percentage of "negative" type were higher in Groups A and B than in the controls.

CONCLUSION

After vasovasostomy a lower level of HOST remained for one year and gradually recovered after one year. Six months after vasectomy reversal, the percentage of acrosome reaction could be changed from lower level to normal range. The data of AO indicated that the genetic material (double-stranded DNA) in spermatozoa was not affected by vasovasostomy. To evaluate the result of CMPT after vasectomy reversal, not only the normal results but also the abnormal results ("poor" and "negative" types) should also be considered.

Zebrafish Mesp family genes, mesp-a and mesp-b are segmentally expressed in the presomitic mesoderm, and Mesp-b confers the anterior identity to the developing somites

Segmentation of a vertebrate embryo begins with the subdivision of the paraxial mesoderm into somites through a not-well-understood process. Recent studies provided evidence that the Notch-Delta and the FGFR (fibroblast growth factor receptor) signalling pathways are required for segmentation. In addition, the Mesp family of bHLH transcription factors have been implicated in establishing a segmental prepattern in the presomitic mesoderm. In this study, we have characterized zebrafish mesp-a and mesp-b genes that are closely related to Mesp family genes in other vertebrates. During gastrulation, only mesp-a is expressed in the paraxial mesoderm at the blastoderm margin. During the segmentation period, both genes are segmentally expressed in one to three stripes in the anterior parts of somite primordia. In fused somites (fss) embryos, in which all early somite boundary formation is blocked, initial mesp-a expression at the gastrula stage remains intact, but the expression of mesp-a and mesp-b is not detected during the segmentation period. This suggests that these genes are downstream targets of fss at the segmentation stage. Comparison with her1 expression (Muller, M., von Weizsacker, E. and Campos-Ortega, J. A. (1996) Development 122, 2071–2078) suggests that, like her1, mesp genes are not expressed in primordia of the first several somites. Furthermore, we found that zebrafish her1 expression oscillates in the presomitic mesoderm. The her1 stripe, which first appears in the tailbud region, moves in a caudal to rostral direction, and it finally overlaps the most rostral mesp stripe. Thus, in the trunk region, both her1 and mesp transcripts are detected in every somite primordium posterior to the forming somites. Ectopic expression of Mesp-b in embryos causes a loss of the posterior identity within the somite primordium, leading to a segmentation defect. These embryos show a reduction in expression of the posterior genes, myoD and notch5, with uniform expression of the anterior genes, FGFR1, papc and notch6. These observations suggest that zebrafish mesp genes are involved in anteroposterior specification within the presumptive somites, by regulating the essential signalling pathways mediated by Notch-Delta and FGFR.

A simple method for measuring the Q value of an NMR sample coil

A simple method for measuring the Q (quality factor) value of an NMR sample coil based on an impedance matching principle is described. This method has the advantage of utilizing a signal generator and reflection coefficient bridge rather than an expensive high-frequency Q meter and offers an alternative means of measuring the Q value of an NMR sample coil or any other radio frequency coil.

Sequence and embryonic expression of deltaC in the zebrafish

Four genes - deltaA, deltaB, deltaC and deltaD - coding for homologues of the Notch ligand Delta have been discovered in zebrafish (Haddon et al., 1998b). We report here the cDNA sequence and expression pattern of deltaC. Its closest relatives are deltaB and Xenopus X-Delta-2. Unlike deltaA, deltaB, and deltaD, deltaC is not expressed in the majority of nascent primary neurons; but it is strongly expressed in the early retina, where it precedes other delta genes. It is also expressed in cranial ganglia, in sensory epithelia including ear and lateral line, and in scattered epidermal cells. In the mesoderm, expression is visible by 50% epiboly; it is seen subsequently in the tail bud, in stripes in the presomitic mesoderm and in the posterior half of each somite. There is expression also in notochord, blood vessels and pronephros.

Vertebrate segmentation: the clock is linked to Notch signalling

The periodic formation of somites during vertebrate segmentation has been suggested to involve a molecular 'segmentation clock'. Recent observations of cyclic Lunatic fringe expression in chick and mouse embryos link the segmentation clock to Delta-Notch signalling.

Delta-Notch signalling and the patterning of sensory cell differentiation in the zebrafish ear: evidence from the mind bomb mutant

Mechanosensory hair cells in the sensory patches of the vertebrate ear are interspersed among supporting cells, forming a fine-grained pattern of alternating cell types. Analogies with Drosophila mechanosensory bristle development suggest that this pattern could be generated through lateral inhibition mediated by Notch signalling. In the zebrafish ear rudiment, homologues of Notch are widely expressed, while the Delta homologues deltaA, deltaB and deltaD, coding for Notch ligands, are expressed in small numbers of cells in regions where hair cells are soon to differentiate. This suggests that the delta-expressing cells are nascent hair cells, in agreement with findings for Delta1 in the chick. According to the lateral inhibition hypothesis, the nascent hair cells, by expressing Delta protein, would inhibit their neighbours from becoming hair cells, forcing them to be supporting cells instead. The zebrafish mind bomb mutant has abnormalities in the central nervous system, somites, and elsewhere, diagnostic of a failure of Delta-Notch signalling: in the CNS, it shows a neurogenic phenotype accompanied by misregulated delta gene expression. Similar misregulation of delta; genes is seen in the ear, along with misregulation of a Serrate homologue, serrateB, coding for an alternative Notch ligand. Most dramatically, the sensory patches in the mind bomb ear consist solely of hair cells, which are produced in great excess and prematurely; at 36 hours post fertilization, there are more than ten times as many as normal, while supporting cells are absent. A twofold increase is seen in the number of otic neurons also. The findings are strong evidence that lateral inhibition mediated by Delta-Notch signalling controls the pattern of sensory cell differentiation in the ear.

Neural degeneration mutants in the zebrafish, Danio rerio

Forty zebrafish mutants with localized or general neural degeneration are described. The onset and duration of degeneration and the distribution of ectopically dying cells are specific characteristics of each mutant. Mutants are classified into four groups by these parameters. Class I: late focal neural degeneration mutants. These 18 mutants have restricted cell death mainly in the tectum and the dorsal hindbrain after 36 hours. The degeneration does not spread and disappears at later stages of development. Class II: early focal neural degeneration mutants. Ten mutants in this class exhibit transient restricted degeneration affecting mainly the diencephalon, the hindbrain and the spinal cord at 20 hours. The midbrain is less affected. The degeneration shifts to the dorsal diencephalon and the tectum at 36 hours. Class III: late spreading neural degeneration mutants. The 8 mutants in this class display a degeneration that is first seen in the tectum and subsequently spreads throughout the nervous system from 36 hours on. Class IV: early general neural degeneration mutants. This class of four mutants already shows overall cell degeneration in the nervous system at the 15-somite stage. Three of the class I mutants show a change in the pattern of gene expression in the anlage of a brain structure prior to the onset of degeneration. These results suggest that focal cell death may be a useful clue for the detection of early patterning defects of the vertebrate nervous system in regions devoid of visible landmarks.

Mutations affecting development of the midline and general body shape during zebrafish embryogenesis

Tissues of the dorsal midline of vertebrate embryos, such as notochord and floor plate, have been implicated in inductive interactions that pattern the neural tube and somites. In our screen for embryonic visible mutations in the zebrafish we found 113 mutations in more than 27 genes with altered body shape, often with additional defects in CNS development. We concentrated on a subgroup of mutations in ten genes (the midline-group) that cause defective development of the floor plate. By using floor plate markers, such as the signaling molecule sonic hedgehog, we show that the schmalspur (sur) gene is needed for early floor plate development, similar to one-eyed-pinhead (oep) and the previously described cyclops (cyc) gene. In contrast to oep and cyc, sur embryos show deletions of ventral CNS tissue restricted to the mid- and hindbrain, whereas the forebrain appears largely unaffected. In the underlying mesendodermal tissue of the head, sur is needed only for development of the posterior prechordal plate, whereas oep and cyc are required for both anterior and posterior prechordal plate development. Our analysis of sur mutants suggests that defects within the posterior prechordal plate may cause aberrant development of ventral CNS structures in the mid- and hindbrain. Later development of the floor plate is affected in mutant chameleon, you-too, sonic-you, iguana, detour, schmalhans and monorail embryos; these mutants often show additional defects in tissues that are known to depend on signals from notochord and floor plate. For example, sur, con and yot mutants show reduction of motor neurons; median deletions of brain tissue are seen in sur, con and yot embryos; and cyc, con, yot, igu and dtr mutants often show no or abnormal formation of the optic chiasm. We also find fusions of the ventral neurocranium for all midline mutants tested, which may reveal a hitherto unrecognized function of the midline in influencing differentiation of neural crest cells at their destination. As a working hypothesis, we propose that midline-group genes may act to maintain proper structure and inductive function of zebrafish midline tissues.

Zebrafish pigmentation mutations and the processes of neural crest development

Neural crest development involves cell-fate specification, proliferation, patterned cell migration, survival and differentiation. Zebrafish neural crest derivatives include three distinct chromatophores, which are well-suited to genetic analysis of their development. As part of a large-scale mutagenesis screen for embryonic/early larval mutations, we have isolated 285 mutations affecting all aspects of zebrafish larval pigmentation. By complementation analysis, we define 94 genes. We show here that comparison of their phenotypes permits classification of these mutations according to the types of defects they cause, and these suggest which process of neural crest development is probably affected. Mutations in eight genes affect the number of chromatophores: these include strong candidates for genes necessary for the processes of pigment cell specification and proliferation. Mutations in five genes remove part of the wild-type pigment pattern, and suggest a role in larval pigment pattern formation. Mutations in five genes show ectopic chromatophores in distinct sites, and may have implications for chromatophore patterning and proliferation. 76 genes affect pigment or morphology of one or more chromatophore types: these mutations include strong candidates for genes important in various aspects of chromatophore differentiation and survival. In combination with the embryological advantages of zebrafish, these mutations should permit cellular and molecular dissection of many aspects of neural crest development.

Mutations affecting the cardiovascular system and other internal organs in zebrafish

In a screen for early developmental mutants of the zebrafish, we have identified mutations specifically affecting the internal organs. We identified 53 mutations affecting the cardiovascular system. Nine of them affect specific landmarks of heart morphogenesis. Mutations in four genes cause a failure in the fusion of the bilateral heart primordia, resulting in cardia bifida. In lonely atrium, no heart venticle is visible and the atrium is directly fused to the outflow tract. In the overlooped mutant, the relative position of the two heart chambers is distorted. The heart is enormously enlarged in the santa mutant. In two mutants, scotch tape and superglue, the cardiac jelly between the two layers of the heart is significantly reduced. We also identified a number of mutations affecting the function of the heart. The mutations affecting heart function can be subdivided into two groups, one affecting heart contraction and another affecting the rhythm of the heart beat. Among the contractility group of mutants are 5 with no heart beat at all and 15 with a reduced heart beat of one or both chambers. 6 mutations are in the rhythmicity group and specifically affect the beating pattern of the heart. Mutations in two genes, bypass and kurzschluss, cause specific defects in the circulatory system. In addition to the heart mutants, we identified 23 mutations affecting the integrity of the liver, the intestine or the kidney. In this report, we demonstrate that it is feasible to screen for genes specific for the patterning or function of certain internal organs in the zebrafish. The mutations presented here could serve as an entry point to the establishment of a genetic hierarchy underlying organogenesis.

Mutations affecting xanthophore pigmentation in the zebrafish, Danio rerio

In a large-scale screen for mutants with defects in embryonic development we identified 17 genes (65 mutants) specifically required for the development of xanthophores. We provide evidence that these genes are required for three different aspects of xanthophore development. (1) Pigment cell formation and migration (pfeffer and salz); (2) pigment synthesis (edison, yobo, yocca and brie) and (3) pigment translocation (esrom, tilsit and tofu). The number of xanthophore cells that appear in the body is reduced in embryos with mutations in the two genes, salz and pfeffer. In heterozygous and homozygous salz and pfeffer adults, the melanophore stripes are interrupted, indicating that xanthophore cells have an important function in adult melanophore pattern formation. Most other genes affect only larval pigmentation. In embryos mutant for edison, yobo, yocca and brie, differences in pteridine synthesis can be observed under UV light and by thin-layer chromatography. Homozygous mutant females of yobo show a recessive maternal effect. Embryonic development is slowed down and embryos display head and tail truncations. Xanthophores in larvae mutant in the three genes esrom, tilsit and tofu appear less spread out. In addition, these mutants display a defect in retinotectal axon pathfinding. These mutations may affect xanthophore pigment distribution within the cells or xanthophore cell shape. Mutations in seven genes affecting xanthophore pigmentation remain unclassified.

Jaw and branchial arch mutants in zebrafish I: branchial arches

Jaws and branchial arches together are a basic, segmented feature of the vertebrate head. Seven arches develop in the zebrafish embryo (Danio rerio), derived largely from neural crest cells that form the cartilaginous skeleton. In this and the following paper we describe the phenotypes of 109 arch mutants, focusing here on three classes that affect the posterior pharyngeal arches, including the hyoid and five gill-bearing arches. In lockjaw, the hyoid arch is strongly reduced and subsets of branchial arches do not develop. Mutants of a large second class, designated the flathead group, lack several adjacent branchial arches and their associated cartilages. Five alleles at the flathead locus all lead to larvae that lack arches 4–6. Among 34 other flathead group members complementation tests are incomplete, but at least six unique phenotypes can be distinguished. These all delete continuous stretches of adjacent branchial arches and unpaired cartilages in the ventral midline. Many show cell death in the midbrain, from which some neural crest precursors of the arches originate. lockjaw and a few mutants in the flathead group, including pistachio, affect both jaw cartilage and pigmentation, reflecting essential functions of these genes in at least two neural crest lineages. Mutants of a third class, including boxer, dackel and pincher, affect pectoral fins and axonal trajectories in the brain, as well as the arches. Their skeletal phenotypes suggest that they disrupt cartilage morphogenesis in all arches. Our results suggest that there are sets of genes that: (1) specify neural crest cells in groups of adjacent head segments, and (2) function in common genetic pathways in a variety of tissues including the brain, pectoral fins and pigment cells as well as pharyngeal arches.

The identification of genes with unique and essential functions in the development of the zebrafish, Danio rerio

In a large-scale screen, we isolated mutants displaying a specific visible phenotype in embryos or early larvae of the zebrafish, Danio rerio. Males were mutagenized with ethylnitrosourea (ENU) and F2 families of single pair matings between sibling F1 fish, heterozygous for a mutagenized genome, were raised. Egg lays were obtained from several crosses between F2 siblings, resulting in scoring of 3857 mutagenized genomes. F3 progeny were scored at the second, third and sixth day of development, using a stereomicroscope. In a subsequent screen, fixed embryos were analyzed for correct retinotectal projection. A total of 4264 mutants were identified. Two thirds of the mutants displaying rather general abnormalities were eventually discarded. We kept and characterized 1163 mutants. In complementation crosses performed between mutants with similar phenotypes, 894 mutants have been assigned to 372 genes. The average allele frequency is 2.4. We identified genes involved in early development, notochord, brain, spinal cord, somites, muscles, heart, circulation, blood, skin, fin, eye, otic vesicle, jaw and branchial arches, pigment pattern, pigment formation, gut, liver, motility and touch response. Our collection contains alleles of almost all previously described zebrafish mutants. From the allele frequencies and other considerations we estimate that the 372 genes defined by the mutants probably represent more than half of all genes that could have been discovered using the criteria of our screen. Here we give an overview of the spectrum of mutant phenotypes obtained, and discuss the limits and the potentials of a genetic saturation screen in the zebrafish.

The zebrafish epiboly mutants

Epiboly, the enveloping of the yolk cell by the blastoderm, is the first zebrafish morphogenetic movement. We isolated four mutations that affect epiboly: half baked, avalanche, lawine and weg. Homozygous mutant embryos arrest the vegetal progress of the deep cells of the blastoderm; only the yolk syncytial layer of the yolk cell and the enveloping layer of the blastoderm reach the vegetal pole of the embryo. The mutations half baked, avalanche and lawine produce a novel dominant effect, termed a zygotic-maternal dominant effect: heterozygous embryos produced from heterozygous females slow down epiboly and accumulate detached cells over the neural tube; a small fraction of these mutant individuals are viable. Heterozygous embryos produced from heterozygous males crossed to homozygous wild-type females complete epiboly normally and are completely viable. Additionally, embryos heterozygous for half baked have an enlarged hatching gland, a partial dominant phenotype. The phenotypes of these mutants demonstrate that, for the spreading of cells during epiboly, the movement of the deep cells of the blastoderm require the function of genes that are not necessary for the movement of the enveloping layer or the yolk cell. Furthermore, the dominant zygotic-maternal effect phenotypes illustrate the maternal and zygotic interplay of genes that orchestrate the early cell movements of the zebrafish.

Genes controlling and mediating locomotion behavior of the zebrafish embryo and larva

Zebrafish embryos and larvae have stage-specific patterns of motility or locomotion. Two embryonic structures accomplish this behavior: the central nervous system (CNS) and skeletal muscles. To identify genes that are functionally involved in mediating and controlling different patterns of embryonic and larval motility, we included a simple touch response test in our zebrafish large-scale genetic screen. In total we identified 166 mutants with specific defects in embryonic motility. These mutants fall into 14 phenotypically distinct groups comprising at least 48 genes. Here we describe the various phenotypic groups including mutants with no or reduced motility, mechanosensory defective mutants, ‘spastic’ mutants, circling mutants and motor circuit defective mutants. In 63 mutants, defining 18 genes, striation of somitic muscles is reduced. Phenotypic analysis provides evidence that these 18 genes have distinct and consecutive functions during somitic muscle development. The genes sloth (slo) and frozen (fro) already act during myoblast differentiation, while 13 genes appear to function later, in the formation of myofibers and the organization of sarcomeres. Mutations in four other genes result in muscle-specific degeneration. 103 mutations, defining at least 30 genes, cause no obvious defects in muscle formation and may instead affect neuronal development. Analysis of the behavioral defects suggests that these genes participate in the diverse locomotion patterns observed, such as touch response, rhythmic tail movements, equilibrium control, or that they simply confer general motility to the animal. In some of these mutants specific defects in the developing nervous system are detected. Mutations in two genes, nevermind (nev) and macho (mao), affect axonal projection in the optic tectum, whereas axon formation and elongation of motorneurons are disrupted by mutations in the diwanka (diw) and the unplugged (unp) genes.

Mutations in zebrafish genes affecting the formation of the boundary between midbrain and hindbrain

Mutations in two genes affect the formation of the boundary between midbrain and hindbrain (MHB): no isthmus (noi) and acerebellar (ace). noi mutant embryos lack the MHB constriction, the cerebellum and optic tectum, as well as the pronephric duct. Analysis of noi mutant embryos with neuron-specific antibodies shows that the MHB region and the dorsal and ventral midbrain are absent or abnormal, but that the rostral hindbrain is unaffected with the exception of the cerebellum. Using markers that are expressed during its formation (eng, wnt1 and pax-b), we find that the MHB region is already misspecified in noi mutant embryos during late gastrulation. The tectum is initially present and later degenerates. The defect in ace mutant embryos is more restricted: MHB and cerebellum are absent, but a tectum is formed. Molecular organisation of the tectum and tegmentum is disturbed, however, since eng, wnt1 and pax-b marker gene expression is not maintained. We propose that noi and ace are required for development of the MHB region and of the adjacent mid- and hindbrain, which are thought to be patterned by the MHB region. Presence of pax-b RNA, and absence of pax-b protein, together with the observation of genetic linkage and the occurrence of a point mutation, show that noi mutations are located in the pax-b gene. pax-b is a vertebrate orthologue of the Drosophila gene paired, which is involved in a pathway of cellular interactions at the posterior compartment boundary in Drosophila. Our results confirm and extend a previous report, and show that at least one member of this conserved signalling pathway is required for formation of the boundary between midbrain and hindbrain in the zebrafish.

Genes involved in forebrain development in the zebrafish, Danio rerio

We identified four zebrafish mutants with defects in forebrain induction and patterning during embryogenesis. The four mutants define three genes: masterblind (mbl), silberblick (slb), and knollnase (kas). In mbl embryos, the anterior forebrain acquires posterior forebrain characteristics: anterior structures such as the eyes, olfactory placodes and the telencephalon are missing, whereas the epiphysis located in the posterior forebrain is expanded. In slb embryos, the extension of the embryonic axis is initially delayed and eventually followed by a partial fusion of the eyes. Finally, in kas embryos, separation of the telencephalic primordia is incomplete and dorsal midline cells fail to form a differentiated roof plate. Analysis of the mutant phenotypes indicates that we have identified genes essential for the specification of the anterior forebrain (mbl), positioning of the eyes (slb) and differentiation of the roof plate (kas). In an appendix to this study we list mutants showing alterations in the size of the eyes and abnormal differentiation of the lenses.