[Clinical characteristics of perimenopausal female patients with rheumatoid arthritis].

Objective: To explore the menopause status of patients with rheumatoid arthritis (RA) and clinical characteristics of perimenopausal RA patients. Methods: A cross-sectional study. Female RA patients were recruited retrospectively in the Sun Yat-Sen Memorial Hospital from August 2015 to August 2023. Clinical data were collected, including onset age, disease duration, RA disease activity indicators, functional assessment, and radiographic scores. According to menopausal status, the patients were categorized as pre-menopausal, perimenopausal and post-menopausal groups to explore their menopausal and clinical characteristics. Results: A total of 1 151 female patients were enrolled, with a mean age of (50.2±13.0) years. At enrollment, there were 470 (40.8%), 140 (12.2%) and 541 (47.0%) patients in pre-menopause, perimenopause and post-menopause status, respectively. The mean age of menopause was (49.0±4.2) years. Compared with pre-menopausal group, perimenopausal RA patients had higher disease activity indicators [clinical disease activity index (CDAI) 17 (6, 26) vs 10 (3, 19) ], higher levels of inflammation [erythrocyte sedimentation rate (ESR) 35 (21, 65) vs 26 (14, 44) mm/1h, C-reactive protein (CRP) 6.2 (3.2, 16.8) vs 3.3 (3.2, 13.6) mg/L], and a higher proportion of functional limitation [25.0%(35/140) vs 10.4%(49/470)] (all P<0.016 7); while there was no significant differences in disease activity[M(Q1, Q3)] [CDAI 17 (6, 26) vs 14 (6, 25)], levels of inflammation [ESR 35(21, 65) vs 42 (23, 72) mm/1h, CRP 6.2 (3.2, 16.8) vs 6.2 (3.3, 23.9) mg/L] and functional limitation [25.0%(35/140) vs 28.8%(156/541)] when compared with those in post-menopausal group (all P>0.016 7). In RA patients during the perimenopausal period, 49 cases (35.0%) developed RA during this period. Compared with patients with RA onset during reproductive age, patients with RA onset during the perimenopausal period had higher numbers of 28-joint tender joints [7 (2, 10) vs 4 (0, 8)], higher CDAI [20 (12, 29) vs 14 (4, 24)], and higher ESR [45 (25, 72) vs 32 (18, 56) mm/1h] (all P<0.05). Conclusion: Perimenopausal patients with RA have severe disease activity and functional limitation.

[Hepatitis B virus infection status and clinical characteristics in patients with rheumatoid arthritis].

Objective: To investigate the epidemiology of hepatitis B virus (HBV) infection in patients with rheumatoid arthritis (RA) in China and its association with RA disease characteristics. Methods: A cross-sectional study. A retrospective study was conducted on RA patients recruited from January 2001 to February 2023 in the Department of Rheumatology and Immunology, Sun Yat-Sen Memorial Hospital. Demographic and clinical data were collected including age, gender, disease duration, active smoking, RA disease activity, physical function, radiographic assessment, serological markers of HBV infection and liver function indicators. According to the status of HBV infection, RA patients were grouped as chronic HBV infection, resolved HBV infection and no HBV infection groups. The distribution of each group and the clinical characteristics of RA patients were analyzed. Results: Among 1 941 RA patients, 1 461 (75.3%) completed HBV screening, including 335 males (22.9%) and 1 126 females (77.1%), with a mean age of (55.4±13.1) years. The prevalence of chronic HBV infection was 10.1%(148/1 461), which was significantly higher in male patients than in females [14.6%(49/335) vs 8.8%(99/1 126), P<0.001], especially among those males born from 1970 to 1979[20.0%(7/35) vs 8.5%(17/201), P=0.037] and 1980-1989 [31.8%(7/22) vs 10.5%(14/133), P=0.007]. Among 148 RA patients with chronic HBV infection, there were 5 cases (3.4%) of chronic hepatitis B, 2 cases (1.4%) of HBV-associated cirrhosis and 1 case (0.7%) of hepatocellular carcinoma. The prevalence of resolved HBV infection was 57.6%(841/1 461). There were 472(32.3%) patients with no HBV infection and 267(56.6%) of them showed negative anti-HBs. Among all RA patients, 15 (1.0%) patients had abnormal liver function, of which 7 cases were drug-induced liver injury, 5 cases were chronic hepatitis B, 2 cases were non-alcoholic fatty liver disease, and 1 case was primary biliary cholangitis. Conclusion: Chronic HBV infection remains a common complication in RA patients in China, the infection rate is 10.1%, and the screening and management of HBV infection should be strengthened in clinical practice.

[Immune checkpoint inhibitor-induced eosinophilic fasciitis: a case report and literature review].

A 58-year-old male patient with angioimmunoblastic T-cell lymphoma developed a rash and skin tightness on the face, limbs, and trunk together with joint stiffness and dysfunction after 6 months of treatment with the programmed cell death protein-1 inhibitor camrelizumab. Laboratory tests revealed progressive eosinophilia over 6 months, with the eosinophil count increasing from 0.07×109/L to 3.3×109/L. Magnetic resonance imaging showed thickened skin of both forearms, while T2-weighted imaging showed markedly increased signal intensity within the myofascia. Skin biopsy of the right forearm showed thickened and fibrosed fascia and infiltration of inflammatory cells, including lymphocytes, plasma cells, and eosinophils. The patient was diagnosed with immune checkpoint inhibitor (ICI)-induced eosinophilic fasciitis (EF). After beginning treatment with methylprednisolone (40 mg daily), methotrexate (10 mg/week), and baricitinib (4 mg daily), his symptoms of skin tightness and joint dysfunction significantly improved within 1 month, and his peripheral blood eosinophil count decreased to 0.17×109/L. ICI-induced EF is a rare immune-related adverse reaction. To date, only 20 cases have been reported in published foreign literature, and their clinical characteristics are summarized here. The time from ICI treatment to EF was 12 (8,15) months, and the main clinical manifestations included skin involvement (n=19), joint dysfunction (n=11), myalgia/muscle weakness (n=9), and peripheral eosinophilia (n=16). After treatment, the clinical symptoms of EF improved in 17 patients, and eosinophil counts returned to normal after 3 (1,8) months. EF is a dysfunctional adverse response to ICI therapy. Tumor patients undergoing immunotherapy should be monitored for symptoms of EF. Early treatment is essential for preventing complications.

[Analysis of the entrance and suture method of umbilical incision in gynecological laparoscopy].

Objective: To explore the entrance and suture method of umbilical incision in gynecological laparoscopy. Methods: A total of 204 cases of gynecologic laparoscopy in our hospital from 2013 to 2016 were reviewed respectively. All the cases used two kinds of approach of umbilical incision: intra-umbilical incision and peri-umbilical incision (longitudinal/transverse oblique/arc incision according to the bellybutton natural skin folds) and two methods of suture: the suture of "U" and the suture of the whole subcutaneous tissue. Two groups were randomly assigned based on the entrance and suture method with each group 102 cases. The peri-operative outcomes were compared, including intra-operative and postoperative bleeding, postoperative incision fat liquefaction and infection, incision pain, incision appearance satisfaction and incision healing satisfaction. Results: The difference was statistically significant in the intra-operative and postoperative bleeding between two groups of intra-umbilical incision and peri-umbilical incision (P<0.05). There was statistically significant difference in postoperative incision fat liquefaction, infection and incision pain between two groups of the suture of "U" and the suture of the whole subcutaneous tissue (P<0.05). The incision appearance satisfaction showed no difference (P>0.05), but the difference was statistically significant (P<0.05) in the incision healing satisfaction between two groups. Conclusion: The peri-umbilical incision (longitudinal/transverse oblique/arc incision according to the bellybutton natural skin folds) and suture of the whole subcutaneous tissue can be the feasible modified methods with high practicability and security, good cosmetic result. It should be promoted in gynecologic laparoscopy.

[The expressions and the roles of SDF-1/CXCR-4 and SDF-1/CXCR-4 in human endometriosis].

Objective: To investigate the expressions and significances of SDF-1 and its receptor CXCR-4 in endometriosis. Methods: 50 hysteromyoma patients treated at Beijing Tongren Hospital, Capital Medical University between 1(st) January 2016 and 31(st) December 2017 were divided into control group, that is, non-endometriosis group, while another 50 endometriosis patients were divided into experimental group.The endometrial tissues, endometriosis lesions, and peritoneal fluid samples of hysteromyoma patients were collected by operation.RT-PCR, ELISA and immunohistochemistry were adopted to detect the expressions of SDF-1 and CXCR-4 in the two groups.Cell count was used to analyze the roles of SDF-1 and CXCR4 in the mitosis and proliferation of endometrial stromal cells. Results: The mean value of SDF-1 and CXCR-4 expressions in ascites or peritoneal fluid of endometriosis patients were (2.56±0.33) mg/L and (4.47±0.32) mg/L, respectively. The mean concentrations in ascites or peritoneal fluid in hysteromyoma patients were (1.39±0.36) mg/L and (3.16±0.32) mg/L, respectively.The expressions of SDF-1 and CXCR-4 in ascites or peritoneal fluid of endometriosis patients were both significantly higher than those of patients in non-endometriosis group (P<0.05). SDF-1 and CXCR-4 were expressed in both endometriosis lesions and the glandular epithelial cells and mesenchymal cells of normal endometrial tissue.Positive staining sites were located in the cytoplasm.A value was used to calculate and analyze the expression of immune staining.The mean A value of SDF-1 and CXCR-4 in endometriosis group were 0.21±0.13 and 0.21±0.13, respectively, and the mean A value in normal endometrial tissues were 0.15±0.13 and 0.14±0.13, respectively.The expressions of these two in endometrial tissues were significantly higher than that in normal endometrial tissues, and the differences were statistically significant (P<0.05). The expression of CXCR-4 mRNA was abundant in the mesenchymal cells of endometriosis cultured in vitro.SDF-1 promoted the mitosis and proliferation of endometrial stromal cells cultured in vitro in a dose-dependent manner.The neutralizing antibody against CXCR-4 was obviously inhibited. Conclusion: The high expressions of SDF-1 and CXCR-4 in endometriosis as well as SDF-1 through its specific receptor CXCR-4 promoted the mitosis and proliferation of endometrial stromal cells, suggesting that SDF-1 and CXCR-4 played important roles in the pathogenesis of endometriosis.

Chemical profiling of cerebrospinal fluid by multiple reaction monitoring mass spectrometry.

We report an accelerated biomarker discovery workflow and results of sample screening by mass spectrometry based on multiple reaction monitoring (MRM). This methodology shows promising initial results for the currently unsolved challenge of Parkinson's disease (PD) laboratory diagnosis by biomarker screening. Small molecules present in cerebrospinal fluid (CSF) at low parts per million levels are monitored using specific transitions connecting ion pairs. A set of such transitions constitutes a multidimensional chemical profile used to distinguish and characterize different CSF samples using multivariate statistical methods.

Association between loop diuretic use and fracture risk.

SUMMARY: Loop diuretic use has been shown to be associated with an increased fracture risk, but the findings have been inconsistent. The present meta-analysis suggests that loop diuretics show a significant positive association with the overall risk of total fractures and, specifically, hip fractures. INTRODUCTION: Despite being widely used, there is limited, prospective randomized trial evidence regarding the skeletal effects of loop diuretics. Previous observational studies have reported conflicting findings regarding the association between loop diuretic use and the risk of fractures. METHODS: This meta-analysis of observational studies assessed the association between loop diuretic use and the risk of fractures. The PubMed, EMBASE, and OVID databases were searched for prospective cohort and case-control studies. Relative risks (RR) with 95% confidence intervals (CI) were derived using random-effects models throughout the analysis. RESULTS: Thirteen studies (4 cohort studies and 9 case-control studies) were included, involving 842,644 participants and 108,247 fracture cases. Compared with non-users, people who had taken loop diuretics had an approximately 15% higher risk of total fractures (95% CI, 1.04-1.26; p<0.01), with high heterogeneity between studies (I2=80.5%; p<0.01). The RR was 1.14 (95% CI, 1.08-1.19) for hip fractures and 0.99 (95% CI, 0.93-1.05) for lower arm or wrist fractures. The RR was 1.05 (95% CI, 1.00-1.11) in prospective cohort studies and 1.22 (95% CI, 1.00-1.44) in case-control studies. There was no evidence of publication bias. CONCLUSION: The results suggest that loop diuretics show a significant positive association with the overall risk of total fractures and hip fractures.

Identification and characterization of a novel lymphocystis disease virus isolate from cultured grouper in China.

Grouper Epinephelus spp. is one of the most important mariculture fish species in China and South-East Asian countries. The emerging viral diseases, evoked by iridovirus which belongs to genus Megalocytivirus and Ranavirus, have been well characterized in recent years. To date, few data on lymphocystis disease in grouper which caused by lymphocystis disease virus (LCDV) were described. Here, a novel LCDV isolate was identified and characterized. Based on the sequence of LCDV major capsid protein (MCP) and DNA polymerase gene, we found that the causative agents from different species of diseased groupers were the same one and herein were uniformly defined as grouper LCDV (GLCDV). Furthermore, H&E staining revealed that the nodules on the skin were composed of giant cells that contained inclusion bodies in the cytoplasm. Numerous virus particles with >210 nm in diameter and with hexagonal profiles were observed in the cytoplasm. In addition, phylogenetic analysis based on four iridovirus core genes, MCP, DNA polymerase, myristoylated membrane protein (MMP) and ribonucleotide reductase (RNR), consistently showed that GLCDV was mostly related to LCDV-C, followed by LCDV-1. Taken together, our data firstly provided the molecular evidence that GLCDV was a novel emerging iridovirus pathogen in grouper culture.

Establishment of a new cell line from the heart of giant grouper, Epinephelus lanceolatus (Bloch), and its application in toxicology and virus susceptibility.

A new marine fish cell line, derived from the heart of giant grouper, Epinephelus lanceolatus (Bloch), was established and characterized. The cell line was designated as ELGH and subcultured with more than 60 passages. The ELGH cells were mainly composed of fibroblast-like cells and multiplied well in Leibovitz's L-15 medium supplemented with 10% foetal bovine serum (FBS) at 28 °C. Chromosome analysis indicated that the modal chromosome number was 48. The fluorescent signals were detected in ELGH when transfected with green fluorescent protein reporter plasmids. The 50% cytotoxic concentration (CC50 ) of the extracellular products (ECPs) from Streptococcus iniae and Vibrio alginolyticus E333 on ELGH cells was 60.02 and 12.49 µg mL(-1), respectively. Moreover, the ELGH cells showed susceptibility to Singapore grouper iridovirus (SGIV), but not to soft-shelled turtle iridovirus (STIV), red-spotted grouper nervous necrosis virus (RGNNV) and spring viremia of carp virus (SVCV), which was demonstrated by the presence of a severe cytopathic effect (CPE) and increased viral titres. In addition, electron microscopy observation showed that abundant virus particles were present in the infected cells. Taken together, our data above provided the potential utility of ELGH cells for transgenic and genetic manipulation, as well as cytotoxicity testing and virus pathogenesis.

Diffusion-weighted imaging with fat suppression using short-tau inversion recovery: Clinical utility for diagnosis of breast lesions.

AIM: To compare the utility of conventional diffusion-weighted imaging (DWI) with fat suppression using short-tau inversion recovery (STIR-DWI) for the detection of breast lesions. MATERIALS AND METHODS: Magnetic resonance imaging (MRI) images of 56 patients (both DWI and STIR-DWI performed) were retrospectively analysed. Parameters compared between DWI and STIR-DWI were image artefacts, image signal-to-noise ratio (SNR), apparent diffusion coefficient (ADC), and contrast-to-noise ratio (CNR). Diagnostic utility was assessed using receiver operating characteristic (ROC) analysis. RESULTS: No abnormality was detected in 17 patients, with lesions observed in 39 patients (16 benign, 23 malignant; confirmed by biopsy or surgical histopathology). The rate of image artefacts was significantly lower for STIR-DWI (p < 0.01): quality levels 1 (best), 2, and 3 accounted for 50%, 35.7%, and 14.3% of DWI images, and 96.4%, 3.6% and 0% of STIR-DWI images, respectively. The SNR was not significantly different. ADC values of breast lesions and normal glands were significantly lower for DWI than for STIR-DWI (p = 0.03 and 0.034). ADC values of malignant lesions, but not benign lesions, were significantly lower for DWI than for STIR-DWI (p = 0.02). CNR values of both benign and malignant lesions were not significantly different between DWI and STIR-DWI. The area under the ROC curve, for the use of ADC values to differentiate benign from malignant lesions, was not significantly different between DWI (0.931) and STIR-DWI (0.914). Taking a threshold ADC value of 1.23 × 10(-3) mm(2)/s, the sensitivity and specificity were 87.5% and 87% for DWI, and 87.5% and 82.6% for STIR-DWI, respectively. CONCLUSION: STIR-DWI is adequate for clinical use in breast MRI investigations.

Tuning transverse anisotropy in Co(III)-Co(II)-Co(III) mixed-valence complex toward slow magnetic relaxation.

Two cobalt mixed-valence complexes with different substituents have been prepared and structurally characterized by single-crystal X-ray diffraction to alter slow magnetic relaxation by tailoring the transverse anisotropy. The trinuclear complexes [(L(1))4Co3(H2O)2](NO3)4·CH3OH·5H2O (1-NO3) and [(L(2))4Co3(H2O)2](NO3)4·6H2O (2-NO3) feature a distorted octahedral Co(II) strongly hindered in a trinuclear Co(III)-Co(II)-Co(III) mixed-valence array. Detailed magnetic studies of 1-NO3 and 2-NO3 have been conducted using direct- and alternating-current magnetic susceptibility data. In accordance with variable-field magnetic susceptibility data at low temperatures, high-field electron paramagnetic resonance (HF-EPR) spectroscopy reveals the presence of an easy-plane anisotropy (D > 0) with a significant transverse component, E, in complexes 1-NO3 and 2-NO3. These findings indicate that the onset of the variation of distortion within complex 2-NO3 leads to a suppression of quantum tunneling of the magnetization within the easy plane, resulting in magnetic bistability and slow relaxation behavior. Consequently, the anisotropy energy scale associated with the relaxation barrier, 5.46 cm(-1) (τo = 1.03 × 10(-5) s), is determined by the transverse E term. The results demonstrate that slow magnetic relaxation can be switched through optimization of the transverse anisotropy associated with magnetic ions that possess easy-plane anisotropy.

High-field magnetization and electronic spin resonance study in the twisted honeycomb latticeα-Mn2V2O7.

We report the single-crystal growth of Mn2V2O7and the results of magnetic susceptibility, high-field magnetization up to 55 T and high-frequency electric spin resonance (ESR) measurements for its low-temperatureαphase. Two antiferromagnetic (AFM) ordering at 17.5 K and 3 K and obvious magnetic anisotropy are observed inα-Mn2V2O7upon cooling. In pulsed high magnetic fields, the compound reaches the saturation magnetic moment of ∼10.5µBfor each molecular formula at around 45 T after two undergoing AFM phase transitions atHc1≈ 16 T,Hc2≈ 34.5 T forH//[11-0] andHsf1= 2.5 T,Hsf2= 7 T forH//[001]. In these two directions, two and seven resonance modes are detected by ESR spectroscopy, respectively. Theω1andω2modes ofH//[11-0] can be well described by two-sublattice AFM resonance mode with two zero-field gaps at 94.51 GHz and 169.28 GHz, indicating a hard-axis feature. The seven modes forH//[001] are partially separated by the critical fields ofHsf1andHsf2, displaying the two signs of spin-flop transition. The fittings ofωc1andωc2modes yield zero-field gaps at 69.50 GHz and 84.73 GHz forH//[001], confirming the axis-type anisotropy. The saturated moment and gyromagnetic ratio indicate the Mn2+ion inα-Mn2V2O7is in a high spin state with orbital moment completely quenched. A quasi-one-dimensional magnetism with a zig-zag-chain spin configuration is suggested inα-Mn2V2O7, due to the special neighbor interactions caused by a distorted network structure with honeycomb layer.

Diffusion tensor imaging and 1H-MRS study on radiation-induced brain injury after nasopharyngeal carcinoma radiotherapy.

AIM: To investigate the metabolic characteristics of the temporal lobes following radiation therapy for nasopharyngeal carcinoma using diffusion tensor imaging (DTI) and proton magnetic resonance spectroscopy ((1)H-MRS). MATERIALS AND METHODS: DTI and (1)H-MRS were performed in 48 patients after radiotherapy for nasopharyngeal carcinoma and in 24 healthy, age-matched controls. All patients and controls had normal findings on conventional MRI. Apparent diffusion coefficient (ADC), fractional anisotropy (FA), three eigenvalues λ1, λ2, λ3, N-acetylaspartic acid (NAA)/choline (Cho), NAA/creatinine (Cr), and Cho/Cr were measured in both temporal lobes. Patients were divided into three groups according to time after completion of radiotherapy: group 1, less than 6 months; group 2, 6-12 months; group 3, more than 12 months. Mean values for each parameter were compared using one-way analysis of variance (ANOVA). RESULTS: Mean FA in group 1 was significantly lower compared to group 3 and the control group (p < 0.05). Group-wise comparisons of apparent diffusion coefficient (ADC) values among all the groups were not significantly different. Eigenvalue λ1 was significantly lower in groups 1 and 3 compared to the control group (p < 0.05). NAA/Cho and NAA/Cr were significantly lower in each group compared to the control group (p < 0.01 for both). The decrease in NAA/Cho was greatest in group 1. There were no significant between-group differences regarding Cho/Cr. CONCLUSION: A combination of DTI and (1)H-MRS can be used to detect radiation-induced brain injury, in patients treated for nasopharyngeal carcinoma.

Speed determinacy of travelling waves for a three-component lattice Lotka-Volterra competition system.

In this paper, the invasive speed selection of the monostable travelling wave for a three-component lattice Lotka-Volterra competition system is studied via the upper and lower solution method, as well as the comparison principle. By constructing several special upper and lower solutions, we establish sufficient conditions such that the linear or nonlinear selection is realized.

Angular dependence of spin-flop transition in triangular lattice antiferromagnet Cu2(OH)3Br.

We report angular dependence of spin-flop transition in triangular lattice antiferromagnet Cu2(OH)3Br by angle-dependent magnetization and ESR measurements. The results show that the antiferromagnetic easy magnetization axis is the diagonal direction (θ= 45°) of theac*plane, i.e., the orientation of Cu1 spins based on the magnetic structure (2020Phys. Rev. Lett.125037204), whereas the spin-flop axis is thebaxis. A phenomenological model is proposed to describe the angle-dependent spin-flop transitions. Based on this model, Cu1 spins are sensitive to external magnetic field, while Cu2 spins are robust against to the field, showing partial decoupling. The model is expected to be used in other uniaxial antiferromagnets with a more general easy axis and complex spin-flop transitions.

Risk factors for Clostridioides difficile infection in children: a systematic review and meta-analysis.

BACKGROUND: Clostridioides difficile is considered an urgent threat to human health by the US Centers for Disease Control and Prevention. In recent years, C. difficile has been reported increasingly as a cause of gastrointestinal disease in children, and the prevalence of hospital-acquired C. difficile infection and community-acquired CDI in children is increasing. AIM: To perform a systematic review and meta-analysis of risk factors for CDI in children. METHODS: MEDLINE/PubMed, EMBASE, Web of Science, Scopus, OVID, China National Knowledge Infrastructure, Wanfang (Chinese), SinoMed (Chinese) and Weipu (Chinese) were searched from inception to 12th January 2022. Observational studies (cohort, case-control and cross-sectional) on CDI in children were included in the analysis. Data were pooled using a fixed or random-effects model, and odds ratios (OR) were calculated. FINDINGS: In total, 25 observational studies were included in the analysis. Prior antibiotic exposure [OR 1.93, 95% confidence interval (CI) 1.25-2.97], prolonged hospitalization (OR 14.68, 95% CI 13.24-16.28), history of hospitalization (OR 3.67, 95% CI 1.91-7.06), gastric acid suppressants (OR 1.96, 95% CI 1.41-2.73), male gender (OR 1.18, 95% CI 1.05-1.32), neoplastic disease (OR 3.40, 95% CI, 2.85-4.07), immunodeficiency (OR 4.18, 95% CI 3.25-5.37), solid organ transplantation (OR 4.56, 95% CI 3.95-5.27) and enteral feeding (OR 2.21, 95% CI 1.05-4.62) were associated with increased risk of CDI. CONCLUSION: This systematic review and meta-analysis provides further evidence for the susceptibility factors of CDI to improve clinicians' awareness of CDI, and prevent C. difficile-associated diarrhoea in children.

Establishment and characterization of a new cell line derived from kidney of grouper, Epinephelus akaara (Temminck & Schlegel), susceptible to Singapore grouper iridovirus (SGIV).

A marine fish cell line derived from the kidney of red-spotted grouper, Epinephelus akaara, designated as EAGK was established and characterized. The EAGK cells multiplied well in Leibovitz's L-15 medium containing 10% foetal bovine serum at 25 °C and have been subcultured for more than 90 passages. Karyotyping, chromosomal typing and ribosomal RNA (rRNA) genotyping analysis revealed that EAGK had a modal diploid chromosome number of 82 and was a fibroblast cell line originated from grouper. A severe cytopathic effect was observed in EAGK cells incubated with Singapore grouper iridovirus (SGIV), but not with soft-shelled turtle iridovirus, viral nervous necrosis virus or spring viraemia of carp virus. SGIV replication was further confirmed by immunofluorescence, electron microscopy and virus titre determination. Bright fluorescence was observed after transfection with fluorescent protein reporter plasmids, indicating that EAGK cells can be used to identify gene functions in vitro. In addition, the cell organelles including mitochondria and endoplasm reticulum changed and aggregated around virus factories after SGIV infection, suggested that the EAGK cell line could be an important tool for investigation of iridovirus-host interactions.

Characterizing the impact of high temperature during grain filling on phytohormone levels, enzyme activity and metabolic profiles of an early indica rice variety.

Global warming results in high temperature stress (HTS), which presents severe challenges worldwide for modern agricultural production and will have significant impacts on the yield and quality of crops. Accumulation of photosynthetic products, activity of enzymes involved in sucrose-starch metabolism, phytohormone levels and metabolic profiling using LC-MS were analysed in the flag leaves and/or developing grains subjected to HTS during the grain-filling stage of an indica rice. HTS induced significant yield loss and reduced the grain quality, with lower amylose content. HTS reduced photosynthetic product accumulation in flag leaves and reduced starch accumulation in developing grains, compared to growth under normal temperatures. The activity of enzymes related to sucrose-starch metabolism were dis-regulated in developing grains grown under high temperature (HT). Moreover, phytohormone homeostasis in flag leaves and developing grains was also dramatically disturbed by HT. Metabolic profiling detected many metabolites with remarkably different relative fold abundances at different time points in the developing grain at HT versus normal temperatures, these metabolites were enriched in several HTS response pathways. The change in phytohormone ratio and auxin level might be associated with the reduction in photosynthetic products and their translocation, and ultimately with reduced starch accumulation in the developing grain. The detected metabolites might have different roles in response to the HTS in developing grain at different development stages. These results provide a theoretical reference and basis for future rice production towards higher quality and yield when grown under HTS.

Ecological degradation in protected areas: the case of Wolong Nature Reserve for giant pandas.

It is generally perceived that biodiversity is better protected from human activities after an area is designated as a protected area. However, we found that this common perception was not true in Wolong Nature Reserve (southwestern China), which was established in 1975 as a "flagship" protected area for the world-renowned endangered giant pandas. Analyses of remote sensing data from pre- and post-establishment periods indicate that the reserve has become more fragmented and less suitable for giant panda habitation. The rate of loss of high-quality habitat after the reserve's establishment was much higher than before the reserve was created, and the fragmentation of high-quality habitat became far more severe. After the creation of the reserve, rates of habitat loss and fragmentation inside the reserve unexpectedly increased to levels that were similar to or higher than those outside the reserve, in contrast to the situation before the reserve was created.