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Purpose: To describe the anatomical and histological characteristics of the human MTL (meniscotibial ligament) that keeps the meniscus stable and are rarely discussed. Study design: Descriptive laboratory study. Methods: In total, six fresh-frozen adult cadaver knees were dissected, and the dissection protocol were designed by two experienced anatomy professors. The anatomical morphology of MTL was observed. The main anatomical specimens included meniscus, tibial plateau, MTL. The osteotome was used to excise the portion of the tibial plateau, which could obtain the complex including partial meniscus, MTL, and a tibial fragment. A histopathologic study was performed by two experienced pathologists. Results: Macroscopically, the MTL could be divided into two parts: medial meniscotibial ligament (MMTL)and lateral meniscotibial ligament (LMTL). The MMTL is distributed continuously, whereas the LMTL is discontinuous on the tibial plateau. The average length from the tibial attachment of the LMTL to the articular surface was 19 ± 1.0mm (mean ± SD). The average length from the tibial attachment of the MMTL to the articular surface was 10 ± 1.2 mm (mean ± SD). Microscopy of the MTL showed that the MTL is a ligamentous tissue, composed of a network of oriented collagenous fibers. Conclusions: In all knees, the MTL was inserted on the outer edge of the meniscus, attaching to the tibia below the level of articular cartilage, which was key to maintaining the rotational stability of knee and the meniscus in the physiological position on the tibial plateau. Histological analysis of this ligament demonstrated that the MTL is a veritable ligamentous structure, which is made up of collagen type I-expressing fibroblasts. Clinical relevance: This article contributes to the understanding of the anatomical and histological characteristics of the MTL. It is beneficial to promote the development of relevant surgical techniques for the MTL lesion.
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BACKGROUND: Although highly effective as a component of Helicobacter pylori (H. pylori) treatment regimen, tetracycline is associated with a high incidence of medication-related adverse events. Modified dosing of tetracycline as part of quadruple therapy may improve safety while providing comparable eradication rates. AIM: To evaluate the efficacy and safety of modified dosing of tetracycline in patients receiving tetracycline and furazolidone-containing quadruple therapy in patients with H. pylori infection. METHODS: Consecutive patients (10/2020-12/2021) who received tetracycline and furazolidone quadruple therapy for H. pylori infection at Sir Run Run Shaw Hospital were identified. All patients received tetracycline, furazolidone, proton pump inhibitor, and bismuth for 14 d as primary or rescue therapy. Modified tetracycline dose group received tetracycline 500 mg twice daily while standard group received 750 mg twice daily or 500 mg three times daily. RESULTS: Three hundred and ninety-four patients [mean age = 46.3 ± 13.9, male = 137 (34.8%), and 309 (78.4%) primary therapy] completed tetracycline and furazolidone quadruple therapy for H. pylori infection including those who received modified tetracycline dose in 157 and standard doses in 118 (750 mg twice daily) and 119 (500 mg three times daily). Eradication rates in the modified tetracycline dose group were 92.40% and in the standard groups, eradication rates were 93.20% for 750 mg twice daily group and 92.43% for 500 mg three times daily group, respectively, without statistical difference (P = 0.959). The incidence of adverse events was lower in the modified tetracycline dose (15.3% vs 32.3% and 29.4%; P = 0.002) compared to the standard dose group. CONCLUSION: In a real-world experience, modified tetracycline dosing as part of tetracycline and furazolidone quadruple therapy for 14 d demonstrated high efficacy, comparable to standard tetracycline dose regimens, with a favorable safety profile.
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Helicobacter pylori , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Furazolidona/efeitos adversos , Estudos Retrospectivos , Tetraciclina/efeitos adversos , Antibacterianos/efeitos adversosRESUMO
The further electrification of various fields in production and daily life makes it a topic worthy of exploration to improve the performance of capacitors for a long time, including thin-film capacitors. The discharge energy density of thin-film capacitors that serves as one of the important types directly depends on electric field strength and the dielectric constant of the insulation material. However, it has long been a great challenge to improve the breakdown strength and dielectric constant simultaneously. Considering that boron nitride nanosheets (BNNS) possess superior insulation and thermal conductivity owing to wide band gap and 2-dimensional structure, a bilayer polymer film is prepared via coating BNNS by solution casting on surface of polyethylene terephthalate (PET) films. By revealing the bandgap and insulating behavior with UV absorption spectrum, leakage current, and finite element calculation, it is manifested that nanocoating contributes to enhance the bandgap of polymer films, thereby suppressing the charge injection by redirecting their transport from electrodes. Worthy to note that an ultrahigh breakdown field strength (~ 736 MV m-1), an excellent discharge energy density (~ 8.77 J cm-3) and a prominent charge-discharge efficiency (~ 96.51%) are achieved concurrently, which is ascribed to the contribution of BNNS ultrathin layer. In addition, the modified PET films also have superior comprehensive performance at high temperatures (~ 120 °C). The materials and methods here selected are easily accessible and facile, which are suitable for large-scale roll-to-roll process production, and are of certain significance to explore the methods about film modification suitable for commercial promotion.
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RESEARCH QUESTION: Does kaempferol alleviate postovulatory oocyte ageing, thereby maintaining their early embryonic development capacity? DESIGN: The effects of kaempferol on postovulatory ageing were investigated in vitro and in vivo by short-term kaempferol administration (mature oocytes were cultured in a kaempferol-containing medium for 12 h; mice were intragastrically administered with the appropriate amount of kaempferol for 21 days). Spindle morphology and chromosome alignment, levels of oxidative stress and the gap junction were assessed by immunofluorescence. Fertilization ability and early embryonic development ability of each oocyte group was detected by IVF. Fertilization of the ageing oocyte model was used to explore whether kaempferol could improve adverse pregnancy outcome. RNA-sequencing and quantitative polymerase chain reaction were used to identify the cellular pathways through which kaempferol relieves postovulatory oocyte ageing in vivo. RESULTS: Kaempferol administration altered various processes in the ageing oocytes, including oxidative stress, the peroxisome, TNF signalling, cAMP signalling and the gap junction pathway. Expression of several important genes, such as Sirt1, Mapk1, Ampk and Foxo3, was regulated. Moreover, kaempferol ameliorated adverse pregnancy outcomes of fertilized ageing oocytes. IVF results indicate that kaempferol could partially counteract the effects of oocyte ageing on fertilization capacity (pronucleus: kaempferol, 69.08 ± 2.37% versus aged, 38.95 ± 3.58%) and early embryonic development (blastocyst: kaempferol, 50.02 ± 3.34% versus aged, 30.83 ± 5.46%). CONCLUSIONS: Our results indicate that kaempferol may be a potent natural antioxidant, have implications for animal husbandry and may help improve the success rate of IVF and ICSI. Further clinical trials are needed.
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Senescência Celular , Quempferóis , Feminino , Camundongos , Gravidez , Animais , Quempferóis/farmacologia , Quempferóis/metabolismo , Oócitos , Blastocisto/metabolismo , Desenvolvimento Embrionário , Fertilização in vitroRESUMO
Since the meniscus is an important stabilizing structure of the knee joint and has a significant role in load-bearing and shock absorption, so the complete structural and functional reconstructions of the teared menisci should be done not only after partial meniscectomy but also post total meniscectomy. So far, animal experiments and good clinical practice have showed that TMAT after total meniscectomy has partially solved the problem of structural and functional reconstructions after total meniscectomy. However, partial meniscectomy will also lead to accelerated knee degeneration, and its proportion is much higher than that of patients with total meniscectomy. Herein, the feasibility of PMAT after partial meniscectomy was investigated for the first time by using the 40% posterior horn meniscectomy model of the medial meniscus in Beagle dogs, and also for the first time, TMAT group and the total meniscectomy group were used as control groups. Compared with the TMAT, the transcriptomics evaluation, scanning electron microscope observation, histological regeneration and structure, biomechanical property, inflammation environment, and the knee function post PMAT were more similar to that of normal meniscus was first reported. This study provides a PMAT scheme with clinical translational value for the complete structural and functional reconstruction of the patients with partial meniscectomy and fills the gap in the field of teared meniscus therapy on the basis of quite well clinical applications of the meniscus repair and the TMAT.
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Artroplastia do Joelho/normas , Menisco/cirurgia , Transplante Homólogo/normas , Animais , Artroplastia do Joelho/métodos , Artroplastia do Joelho/estatística & dados numéricos , Cães , Estudos de Viabilidade , Menisco/fisiopatologia , Transplante Homólogo/métodos , Transplante Homólogo/estatística & dados numéricosRESUMO
Perfluorooctane sulphonate (PFOS), as a surfactant, is widely applied in the agricultural production activities and has become a potential menace to human health. The mechanism of its effect on the maturation of mammalian oocytes is unclear. This study explored the toxic effect of PFOS on mouse oocyte maturation in vitro. The results revealed that PFOS under a concentration of 600 µM could significantly reduce the polar body extrusion rate (PBE) of mouse oocytes and cause symmetrical cell division. Further experiments showed that PFOS resulted in the abnormal cytoskeleton of the oocytes, causing the abnormal spindles and misplaced chromosomes, as well as the impaired dynamics of actin. Moreover, PFOS exposure inhibited the process of oocyte meiosis, which reflected in the slower spindle migration and continuous activation of spindle assembly checkpoint (SAC), then ultimately increased the probability of aneuploidy. Most importantly, PFOS exposure reduced the quality of oocytes, specifically by disrupting the function of mitochondria, inducing cell oxidative stress, and triggering early apoptosis. Furthermore, the level of methylation of histones is additionally influenced. In summary, our findings showed that PFOS exposure interfered with the maturation of mouse oocytes through affecting cytoskeletal dynamics, meiotic progression, oocyte quality, and histone modifications.
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Ácidos Alcanossulfônicos , Ácidos Alcanossulfônicos/metabolismo , Ácidos Alcanossulfônicos/toxicidade , Animais , Apoptose , Fluorocarbonos , Camundongos , Oócitos/metabolismo , Estresse OxidativoRESUMO
Fas binding factor 1 (Fbf1) is one of the distal appendage proteins in the centriole, located at its distal and proximal ends. It influences the duplication and separation of centrosomes, thereby affecting the progression of the cell cycle during mitosis. However, the function of Fbf1 in meiosis has remained unclear. To explore the role of Fbf1 in the in vitro maturation of mouse oocyte, immunofluorescence staining was used to examine the Fbf1 location in the oocyte and their phenotype after protein deletion. Western blot was used to examine the protein abundance. This study showed that mouse oocytes express Fbf1 which locates at the spindle poles and around the microtubules. Through taxol and nocodazole treatment, and microinjection of siRNA, it was demonstrated that Fbf1 had an important role in the spindle assembly and chromosome separation during mouse oocyte meiosis In particular, microinjection of Fbf1-siRNA resulted in severe abnormalities in the spindle and chromosome arrangement, decreased aggregation of microtubules, disrupted the first oocyte meiosis, and the extrusion of the first polar body. Furthermore, in the Fbf1-siRNA group, there was reduced expression of Plk1 and its agglutination at the spindle poles, along with retarded chromosome segregation due to the activation of the spindle assembly checkpoint (SAC) component BubR1. These results indicate that Fbf1 may function in microtubule depolymerization and agglutination, control the microtubule dynamics, spindle assembly and chromosome arrangement and, thus, influence the mouse oocyte meiotic maturation.
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Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Ciclo Celular/metabolismo , Meiose , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fuso Acromático , Animais , Camundongos , Microtúbulos , Nocodazol , Oócitos , Quinase 1 Polo-LikeRESUMO
BACKGROUND: Peripheral blood (PB) is a potential source of chondrogenic progenitor cells that can be used for cartilage repair and regeneration. However, the cell types, isolation and implantation methods, seeding dosage, ultimate therapeutic effect, and in vivo safety remain unclear. METHODS: PubMed, Embase, and the Web of Science databases were systematically searched for relevant reports published from January 1990 to December 2019. Original articles that used PB as a source of stem cells to repair cartilage in vivo were selected for analysis. RESULTS: A total of 18 studies were included. Eight human studies used autologous nonculture-expanded PB-derived stem cells (PBSCs) as seed cells with the blood cell separation isolation method, and 10 animal studies used autologous, allogenic or xenogeneic culture-expanded PB-derived mesenchymal stem cells (PB-MSCs), or nonculture-expanded PBSCs as seed cells. Four human and three animal studies surgically implanted cells, while the remaining studies implanted cells by single or repeated intra-articular injections. 121 of 130 patients (in 8 human clinical studies), and 230 of 278 animals (in 6 veterinary clinical studies) using PBSCs for cartilage repair achieved significant clinical improvement. All reviewed articles indicated that using PB as a source of seed cells enhances cartilage repair in vivo without serious adverse events. CONCLUSION: Autologous nonculture-expanded PBSCs are currently the most commonly used cells among all stem cell types derived from PB. Allogeneic, autologous, and xenogeneic PB-MSCs are more widely used in animal studies and are potential seed cell types for future applications. Improving the mobilization and purification technology, and shortening the culture cycle of culture-expanded PB-MSCs will obviously promote the researchers' interest. The use of PBSCs for cartilage repair and regeneration in vivo are safe. PBSCs considerably warrant further investigations due to their superiority and safety in clinical settings and positive effects despite limited evidence in humans.
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Background α-Dicarbonyl compounds (α-DCs) have been detected in body fluids including plasma and urine and elevation of this sort of compounds in vivo has been associated with the development of many kinds of chronic diseases. However whether α-DCs are present in human saliva, and if their presence/absence can be related with various chronic diseases is yet to be determined. Methods In this study, a pre-column derivatization HPLC-UV method was developed to measure 3-deoxyglucosone (3-DG), glyoxal (GO), methylglyoxal (MGO), diacetyl (DA), and pentane-2,3-dione (PD) in human saliva employing 4-(2,3-dimethyl-6-quinoxalinyl)-1,2-benzenediamine (DQB) as a derivatizing reagent. The derivatization of the α-DCs is fast and the conditions are facile. The method was evaluated and the results show that it is suitable for the quantification of α-DCs in human saliva. Results In the measurements of these α-DCs in the saliva of 15 healthy subjects and 23 type 2 diabetes mellitus (T2DM) patients, we found that the concentrations of GO and MGO in the saliva of the diabetic patients were significantly higher than those in healthy subjects. As far as we know, this is the first time that salivary α-DC concentrations have been determined and associated with T2DM. Conclusions The developed method would be useful for the measurement of the salivary α-DC levels and the data acquired could be informative in the early screening for diabetes.
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Desoxiglucose/análogos & derivados , Glioxal/análise , Aldeído Pirúvico/análise , Adulto , Cromatografia Líquida de Alta Pressão/métodos , Desoxiglucose/análise , Diabetes Mellitus Tipo 2/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saliva/químicaRESUMO
The presence of αdicarbonyl compounds (α-DCs) in vivo has been associated with the development of complications of diabetes mellitus (DM) and also with other chronic diseases. Therefore, quantitative analysis of α-DCs in body fluids is crucial to understand their roles in the formation of these chronic diseases. We established in this study a practical HPLC-UV method to measure 3deoxyglucosone (3-DG), glyoxal (GO), methylglyoxal (MGO), diacetyl (DA), and pentane2,3dione (PD) in blood plasma using 4(2,3dimethyl6quinoxalinyl)1,2benzenediamine (DQB) as a derivatizing reagent. The derivatizing reaction could be carried out quickly under mild conditions and the HPLC determination is simple, sensitive, and easy to operate. The recoveries of the α-DCs are between 85.26% and 110.20% (intra-day) and 87.25% and 103.18% (inter-day); the RSDs are between 1.28% and 5.69% (intra-day) and 2.26% and 6.34% (inter-day). We found the plasma levels of 3-DG, GO, and MGO in the diabetic patients are all significantly higher than those in healthy subjects. The results also show that the contents of GO and MGO in diabetic nephropathy (DN) patients are both significantly higher than those in simple T2DM patients. Moreover, it is found for the first time that the plasma level of GO might be a potential predictor of DN. The developed method would be useful for the measurements of the plasma α-DCs and the data acquired could be informative in the diagnosis of DM complications.
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Biomarcadores , Diabetes Mellitus Tipo 2/sangue , Nefropatias Diabéticas/sangue , Idoso , Biomarcadores/sangue , Cromatografia Líquida de Alta Pressão , Desoxiglucose/análogos & derivados , Desoxiglucose/sangue , Nefropatias Diabéticas/diagnóstico , Diacetil/sangue , Feminino , Glioxal/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Aldeído Pirúvico/sangueRESUMO
The root of Cynanchum auriculatum (C. auriculatum) Royle ex Wight has been shown to possess various pharmacological effects and has recently attracted much attention with respect to its potential role in antitumor activity. The C-21 steroidal glycosides are commonly accepted as the major active ingredients of C. auriculatum. In this study, the antitumor abilities of different extracted fractions of the root bark and the root tuber of C. auriculatum were investigated by using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay in human cancer cell lines HepG2 and SMMC-7721. The results showed that the chloroform and ethyl acetate fractions of the root tuber suppressed tumor cell growth strongly. To identify and characterize the chemical constituents of different active fractions, an ultra high performance liquid chromatography with triple-quadrupole tandem mass spectrometry method was developed for the simultaneous quantitation of eight C-21 steroidal glycosides. The analysis revealed that the C-21 steroidal glycosides were concentrated in the chloroform and ethyl acetate fractions, and the total contents of different fractions in the root tuber were significantly higher than those of corresponding ones in the root bark. Furthermore, the C-21 steroidal glycosides based on different types of aglucones were prone in different medicinal parts of C. auriculatum.
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Antineoplásicos Fitogênicos/isolamento & purificação , Cynanchum/química , Glicosídeos/isolamento & purificação , Raízes de Plantas/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/farmacologia , Humanos , Extratos Vegetais/química , Espectrometria de Massas em TandemRESUMO
Diacetyl is an important flavoring compound in many foods, especially in beer. In the present study, we developed and validated a new precolumn derivatization HPLC-UV method for the determination of diacetyl using 4-(2,3-dimethyl-6-quinoxalinyl)-1,2-benzenediamine as a novel derivatizing reagent. After derivatization with the reagent at a pH value 4.0 at ambient temperature for 10 min, diacetyl was analyzed on an ODS column and detected at 254 nm. The results show that the correlation coefficient of the method is 0.9991 in the range of 0.10 to 100.0 µM diacetyl, and the limit of detection is 0.02 µM. The method was further evaluated in the analysis of beer samples with the recoveries ranging from 94.4 to 102.6% and RSDs from 1.36 to 3.33%. The concentrations of diacetyl in 8 beer samples were determined in the range of 0.19 to 0.42 µM. The method established in this study may be well suitable for the determination of diacetyl in beer.
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Cerveja/análise , Cromatografia Líquida de Alta Pressão/métodos , Diacetil/análise , Fenilenodiaminas/química , Quinoxalinas/químicaRESUMO
AIM: To investigate the diagnostic accuracy of FibroScan (FS) in detecting esophageal varices (EV) in cirrhotic patients. METHODS: Through a systemic literature search of multiple databases, we reviewed 15 studies using endoscopy as a reference standard, with the data necessary to calculate pooled sensitivity (SEN) and specificity (SPE), positive and negative LR, diagnostic odds ratio (DOR) and area under receiver operating characteristics (AUROC). The quality of the studies was rated by the Quality Assessment of Diagnostic Accuracy studies-2 tool. Clinical utility of FS for EV was evaluated by a Fagan plot. Heterogeneity was explored using meta-regression and subgroup analysis. All statistical analyses were conducted via Stata12.0, MetaDisc1.4 and RevMan5. RESULTS: In 15 studies (n = 2697), FS detected the presence of EV with the summary sensitivities of 84% (95%CI: 81.0%-86.0%), specificities of 62% (95%CI: 58.0%- 66.0%), a positive LR of 2.3 (95%CI: 1.81-2.94), a negative LR of 0.26 (95%CI: 0.19-0.35), a DOR of 9.33 (95%CI: 5.84-14.92) and an AUROC of 0.8262. FS diagnosed the presence of large EV with the pooled SEN of 0.78 (95%CI: 75.0%-81.0%), SPE of 0.76 (95%CI: 73.0%-78.0%), a positive and negative LR of 3.03 (95%CI: 2.38-3.86) and 0.30 (95%CI: 0.23-0.39) respectively, a summary diagnostic OR of 10.69 (95%CI: 6.81-16.78), and an AUROC of 0.8321. A meta-regression and subgroup analysis indicated different etiology could serve as a potential source of heterogeneity in the diagnosis of the presence of EV group. A Deek's funnel plot suggested a low probability for publication bias. CONCLUSION: Using FS to measure liver stiffness cannot provide high accuracy for the size of EV due to the various cutoff and different etiologies. These limitations preclude widespread use in clinical practice at this time; therefore, the results should be interpreted cautiously given its SEN and SPE.
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Técnicas de Imagem por Elasticidade/métodos , Varizes Esofágicas e Gástricas/diagnóstico por imagem , Esofagoscopia , Esôfago/diagnóstico por imagem , Cirrose Hepática/complicações , Varizes Esofágicas e Gástricas/etiologia , Humanos , Razão de Chances , Valor Preditivo dos Testes , Curva ROC , Índice de Gravidade de DoençaRESUMO
OBJECTIVE: To observe the effect of subarachnoid nerve block anesthesia on glutamate transporter glutamate-aspartate transporter (GLAST) and GLT-1 expressions in rabbits, and to investigate the effect of peripheral nerve anesthesia on the morphology and function of the spinal cord. METHODS: Twenty healthy New Zealand white rabbits were randomly divided into two groups: the experimental group and control group; with 10 rabbits in each group. For spinal nerve anesthesia, 5 g/L of bupivacaine was used in the experimental group, and sterile saline was used in the control group. After 30 min of cardiac perfusion, GLAST and GLT-1 protein expression in spinal neurons were detected by immunohistochemistry and immunofluorescence staining. RESULTS: GLAST and GLT-1 protein-positive cells increased in neurons in the experimental group, compared with the control group (P < 0.05). CONCLUSIONS: After subarachnoid nerve block anesthesia, rabbit glutamate transporter GLAST and GLT-1 expression is increased; and spinal cord nerve cell function is inhibited.
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OBJECTIVE: To establish a 29 Y-STR loci multiplex PCR system for investigating the genetic polymorphisms and to assess its application value in forensic science. METHODS: A multiplex PCR system was established using a five color fluorescence labeling 29 Y-STR loci (DYS456, DYS389 I , DYS437, DYS447, DYS389 11, DYS438, DYS522, DYS460, DYS458, DYS622, DYS390, DYS392, DYS448, DYS449, DYS391, Y-GA TA-H4, DYS388, DYS19, DYS385a/b, DYS527a/b, DYS393, DYS459a/b, DYS635, DYS439, DYS570 and DYS627) for multiple amplification and capillary electrophoresis. And its applicability was validated with genetic polymorphism data of 29 Y-STR of unrelated 2,000 male samples in Shandong Han population. RESULTS: A total of 1,981 different haplotypes of 2,000 individuals showed genotype diver- sity between 0.370 0 and 0.965 4. The system provided stable and accurate typing with high sensitivity of 0.05 ng. It satisfied the needs of variety of routine biological samples. CONCLUSION: The 29 Y-STR loci multiplex PCR system could be applied for actual cases and establishment of Y-STR database. In addition, it has great significance in forensic science practices and related research.
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Povo Asiático/genética , Cromossomos Humanos Y , Etnicidade/genética , Genética Populacional , Haplótipos , Reação em Cadeia da Polimerase Multiplex/métodos , China , DNA/análise , DNA/genética , DNA/isolamento & purificação , Genética Forense/métodos , Ciências Forenses , Genética Populacional/métodos , Humanos , Masculino , Repetições de Microssatélites , Polimorfismo Genético , Reprodutibilidade dos TestesRESUMO
Based on data obtained from 572 branches of 45 Chinese fir trees in Jiangle Forest Farm, Fujian Province, southeast China, prediction models for branch, foliage biomass and total branch and foliage biomass of individual tree were developed by linear mixed effects (LME) method, and tested by independent samples. The results showed that the LME models provided better performance than the multiple linear regression models for the branch, foliage and total biomass prediction of Chinese fir plantation. The LME models with different combinations of the random effects parameters had different fitting precisions. The LME models including variance structures could effectively remove the heteroscedasticity in the data and improved the precision. The LME model with the exponential function as the variance structure had better fitting precisions for the total biomass and foliage biomass models, and that with the constant plus power function as the variance structure had better performance for the branch biomass model. Model validation confirmed that the LME models with the random effects and heteroscedasticity structure could significantly improve the precision of prediction, compared to the multiple linear regression models.
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Cunninghamia/crescimento & desenvolvimento , Florestas , Modelos Lineares , Biomassa , China , Árvores/crescimento & desenvolvimentoRESUMO
Hepatitis E virus (HEV), the causative agent of hepatitis E, is classified into four major genotypes (1 to 4) and swine is the main natural reservoir for genotypes 3 and 4. In this study, a total of 106 bile samples from a slaughterhouse in the Shandong province of China were tested for the partial ORF2 gene of HEV by RT-nPCR to determine the virus genotypes, and two indirect ELISA were developed for the detection of swine HEV specific IgM and IgG antibodies in 980 serum samples from 24 farms, in order to investigate the seroprevalence. Thirty-two out of 106 (30.2%) bile samples were positive for HEV and a high degree of partial ORF2 sequence similarity (86.8-100%) was observed among 20 samples. The viral sequences belonged to genotype 4, subtypes 4a and 4d. One complete genome sequence of a subtype 4d HEV was further determined and characterized. The seroprevalence of HEV IgG and IgM antibodies was 100% (24/24) and 41.7% (10/24) for herds, and 66.4% (651/980) and 1.6% (16/980) for the individual pigs, respectively. These results suggested a high prevalence of genotype 4 of swine HEV infection both in swine farms and at the slaughterhouse in Shandong province, which further raise public-health concerns for zoonosis and pork safety.
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Vírus da Hepatite E/genética , Hepatite E/veterinária , Doenças dos Suínos/virologia , Matadouros , Animais , China/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Inocuidade dos Alimentos , Genótipo , Hepatite E/epidemiologia , Hepatite E/virologia , Carne/virologia , Filogenia , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/epidemiologia , ZoonosesRESUMO
This research chose five lead-contaminated sites of a lead-acid battery factory to analyze the speciation distribution and concentration of lead. Under the same conditions (0.1 mol x L(-1) EDTA,30 min, 25 degrees C), the removal effect of heavy metal was compared between ultrasonic-assisted chemical extraction (UCE) and conventional chemical extraction ( CCE), and the variation of lead speciation was further explored. The results showed that the lead removal efficiency of UCE was significantly better than CCE. The lead removal efficiency of WS, A, B, C and BZ was 10.06%, 48.29%, 48.69%, 53.28% and 36.26% under CCE. While the removal efficiency of the UCE was 22.42%, 69.31%, 71.00%, 74.49% and 71.58%, with the average efficiency higher by 22%. By comparing the speciation distribution of the two washing methods, it was found that the acid extractable content maintained or decreased after UCE, whereas it showed an increasing trend after CCE. The reduction effect of the reducible was as high as 98% by UCE. UCE also showed a more efficient reduction effect of the organic matter-sulfite bounded form and the residual form. Hence, it is feasible to improve the washing efficiency of heavy metal contained in soil by conducting the cleaning process with the help of ultrasonic wave, which is a simple and fast mean to remove lead from contaminated sites.
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Recuperação e Remediação Ambiental/métodos , Chumbo/química , Poluentes do Solo/química , Solo/química , Ultrassom , Ácidos , IndústriasRESUMO
Avian hepatitis E virus (HEV) is an emerging virus associated with the big liver and spleen disease or hepatitis-splenomegaly syndrome in chickens and subclinical infections by the virus are also common. The complete genome of avian HEV contains three open-reading frames (ORFs) in which ORF2 protein is part of virus particles and thus contains primary epitopes. Antigenic epitopes of avian HEV ORF2 protein have been described but those associated with the ORF3 have not. To analyze the antigenic domains and epitopes in the ORF3 protein of a Chinese isolate of avian HEV (CaHEV), we generated a series of antigens comprised of the complete ORF3 and also five truncated overlapping ORF3 peptides. The antibodies used in this study were mouse antisera and monoclonal antibodies against ORF3, positive chicken sera from Specific Pathogen Free chickens experimentally infected with CaHEV and clinical chicken sera. Using these antigens and antibodies, we identified three antigenic domains at amino acids (aa) 1-28, 55-74 and 75-88 in which aa 75-88 was a dominant domain. The dominant domain contained at least two major epitopes since field chickens infected with avian HEV produced antibodies against the domain and epitopes. These results provide useful information for future development of immunoassays for the diagnosis of avian HEV infection.
Assuntos
Epitopos/imunologia , Hepevirus/genética , Hepevirus/imunologia , Proteínas Virais/genética , Proteínas Virais/imunologia , Animais , Galinhas/imunologia , Galinhas/virologia , China , Epitopos/genética , Escherichia coli/genética , Soros Imunes/metabolismo , Camundongos , Dados de Sequência Molecular , Peptídeos/genética , Peptídeos/imunologia , Estrutura Terciária de Proteína/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Organismos Livres de Patógenos EspecíficosRESUMO
To analyze the growth, proliferation, apoptosis, invasiveness and chemotherapy sensitivity of EC9706 cells after K-Ras gene silencing, an expression carrier pSilencer-siK-Ras was constructed, and the EC9706 cell line was transfected using a liposome technique. Six groups were established: Control, siRNA NC (transfected with empty vector pSilencer2.1); Ras siRNA (transfected with pSilencer-siK-Ras2); Paclitaxel; Paclitaxel + siRNA NC; and Ras siRNA +Paclitaxel. After the treatment, RT-PCR, Western blotting, MTT assay, flow cytometry and the Transwell technique were used to assess expression of K-Ras mRNA and protein in EC9706 cells, as well as cell growth, proliferation, apoptosis and invasiveness. The effect of Paclitaxel chemotherapy was also tested. pSilencer-siK-Ras2 effectively down-regulated expression of K-Ras mRNA and protein in EC9706 cells, growth being significantly inhibited. Flow cytometry indicated obvious apoptosis of cells in the experimental group, with arrest in the G1 phase; cell migration ability was also reduced. After pSilencer-siK-Ras2 transfection or the addition of Paclitaxel, EC9706 cells were suppressed to different extents; the suppressive effect was strengthened by combined treatment. The results suggested that RNAi-induced K-Ras gene silencing could enhance chemotherapy sensitivity of esophageal cancer.