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1.
Phys Rev E ; 106(5-1): 054104, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36559519

RESUMO

We investigate the ground-state phase diagram for a spin-one quantum Heisenberg antiferromagnetic chain with exchange and single-ion anisotropies in an external magnetic field by using the infinite time-evolving block decimation algorithm to compute the ground-state fidelity per lattice site. We detect all phase boundaries solely by computing the ground-state fidelity per lattice site, with the prescription that a phase transition point is attributed to a pinch point on the ground-state fidelity surface. Furthermore, the results indicate that a magnetization plateau corresponds to a fidelity plateau on the ground-state fidelity surface, thus offering an alternative route for investigating the magnetization processes of quantum many-body spin systems. We characterize all phases by using the local-order parameter, the spin correlation, the momentum distribution of the spin correlation structure factor, and mutual information as a function of the lattice distance. The commensurate and incommensurate phases are distinguished by the mutual information. In addition, the central charges at criticalities are identified by performing a finite-entanglement scaling analysis. The results show that all phase transitions between spin liquids and magnetization plateaus belong to the Pokrovsky-Talapov universality class.

2.
Sci Rep ; 9(1): 13993, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31570751

RESUMO

Patients suffer bilateral sacral plexus injuries experience severe problems with incontinence. We performed a cadaveric study to explore the anatomical feasibility of transferring ipsilateral S2 nerve root combined with a sural nerve graft to pudendal nerve for restoration of external anal and urethral sphincter function. The sacral nerve roots and pudendal nerve roots on the right side were exposed in 10 cadavers. The length from S2 nerve root origin to pudendal nerve at inferior border of piriformis was measured. The sural nerve was used as nerve graft. The diameters and nerve cross-sectional areas of S2 nerve root, pudendal nerve and sural nerve were measured and calculated, so as the number of myelinated axons of three nerves on each cadaver specimen. The length from S2 nerve root to pudendal nerve was 10.69 ± 1.67 cm. The cross-sectional areas of the three nerves were 8.57 ± 3.03 mm2 for S2, 7.02 ± 2.04 mm2 for pudendal nerve and 6.33 ± 1.61 mm2 for sural nerve. The pudendal nerve contained approximately the same number of axons (5708 ± 1143) as the sural nerve (5607 ± 1305), which was a bit less than that of the S2 nerve root (6005 ± 1479). The S2 nerve root in combination with a sural nerve graft is surgically feasible to transfer to the pudendal nerve for return of external urethral and anal sphincter function, and may be suitable for clinical application in patients suffering from incontinence following sacral plexus injuries.


Assuntos
Canal Anal/inervação , Nervo Pudendo/cirurgia , Raízes Nervosas Espinhais/cirurgia , Nervo Sural/transplante , Uretra/inervação , Adulto , Canal Anal/cirurgia , Estudos de Viabilidade , Incontinência Fecal/cirurgia , Feminino , Humanos , Masculino , Nervo Pudendo/anatomia & histologia , Raízes Nervosas Espinhais/anatomia & histologia , Nervo Sural/anatomia & histologia , Uretra/cirurgia , Incontinência Urinária/cirurgia
3.
Mol Ther ; 27(3): 531-541, 2019 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-30692016

RESUMO

Osteoarthritis (OA), the most prevalent age-related joint disorder, is characterized by chronic inflammation, progressive articular cartilage destruction, and subchondral bone sclerosis. Accumulating evidences indicate that circular RNAs (circRNAs) play a critical role in various diseases, but the function of circRNAs in OA remains largely unknown. Here we showed that circRNA.33186 was significantly upregulated in IL-1ß)-treated chondrocytes and in cartilage tissues of a destabilized medial meniscus (DMM)-induced OA mouse model. Knockdown of circRNA.33186 increased anabolic factor (type II collagen) expression and decreased catabolic factor (MMP-13) expression. Knockdown of circRNA.33186 also promoted proliferation and inhibited apoptosis in IL-1ß-treated chondrocytes. Silencing of circRNA.33186 in vivo markedly alleviated DMM-induced OA. Mechanistic study showed that circRNA.33186 directly binds to and inhibits miR-127-5p, thereby increasing MMP-13 expression, and contributes to OA pathogenesis. Taken together, our findings demonstrated a fundamental role of circRNA.33186 in OA progression and provide a potential drug target in OA therapy.


Assuntos
MicroRNAs/metabolismo , Osteoartrite/patologia , RNA Circular/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Western Blotting , Proliferação de Células/genética , Proliferação de Células/fisiologia , Células Cultivadas , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Imunofluorescência , Imuno-Histoquímica , Interleucina-1beta/metabolismo , Masculino , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Osteoartrite/genética , Osteoartrite/metabolismo , RNA Circular/genética
4.
BMC Musculoskelet Disord ; 18(1): 187, 2017 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-28499431

RESUMO

BACKGROUND: Current treatments for proximal humeral fractures include conservative treatment, conventional open reduction internal fixation (ORIF) and MIPPO through deltoid-splitting approach. The aim of this study was to evaluate the clinical outcome of MIPPO versus ORIF via the deltoid-pectoralis approach in elderly patients with proximal humeral fractures. METHODS: Thirty-six patients with proximal humeral fractures were enrolled in this study. Following the randomized block and single-blinded principle, the patients were assigned to two groups and treated with either conventional ORIF or MIPPO, both through the deltoid-pectoralis approach. Surgical outcomes were evaluated by the NEER score, Constant-Murley score, blood loss, length of operation, radiological imaging and clinical examination. The patients were followed up for 4-24 (mean 10) months. RESULTS: According to Constant-Murley score, the surgical outcome was excellent in 14 cases, satisfactory in 2 cases and unsatisfactory in one case in MIPPO group versus 10, 5 and 4 in conventional ORIF group. MIPPO was significantly advantageous over conventional ORIF in terms of NEER score, Constant-Murley, length of operation and intraoperative blood loss. In addition, MIPPO was also more advantageous in several indexes in patients with BMI > 26.0 and NEER type III fracture. CONCLUSION: The results of our study have demonstrated that MIPPO through the deltoid-pectoralis approach is an effective alternative for the treatment of proximal humeral fractures in elderly patients. TRIAL REGISTRATION: The trial registration number (TRN): ChiCTR-INR-17011098 (retrospectively registered at 2017-04-09).


Assuntos
Placas Ósseas , Músculo Deltoide/cirurgia , Fixação Interna de Fraturas/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Músculos Peitorais/cirurgia , Fraturas do Ombro/cirurgia , Idoso , Músculo Deltoide/diagnóstico por imagem , Feminino , Seguimentos , Fixação Interna de Fraturas/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Músculos Peitorais/diagnóstico por imagem , Estudos Prospectivos , Fraturas do Ombro/diagnóstico por imagem , Método Simples-Cego , Resultado do Tratamento
5.
J Zhejiang Univ Sci B ; 17(3): 218-24, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26984842

RESUMO

Recurrent pregnancy loss (RPL) is a condition with complex etiologies, to which both genetic and environmental factors may contribute. During the last decade, studies indicated that the expression patterns of the prokineticin receptor (PKR1 and PKR2) are closely related to early pregnancy. However, there are few studies on the role of PKR1 and PKR2 in RPL. In this study, we purpose to investigate the association between polymorphisms of the prokineticin receptor (PKR1 rs4627609 and PKR2 rs6053283) and RPL on a group of 93 RPL cases and 169 healthy controls. Genotyping of the single nucleotide polymorphisms (SNPs) was performed using a Sequenom MassARRAY iPLEX system. The results revealed a significant association between PKR2 rs6053283 polymorphism and RPL (P=0.003), whereas no association was observed between PKR1 rs4627609 polymorphism and RPL (P=0.929) in the Chinese Han population.


Assuntos
Aborto Habitual/genética , Polimorfismo de Nucleotídeo Único , Receptores Acoplados a Proteínas G/genética , Receptores de Peptídeos/genética , Aborto Habitual/etiologia , Adulto , Povo Asiático/genética , China/etnologia , Feminino , Hormônios Gastrointestinais/fisiologia , Humanos , Gravidez , Fator de Crescimento do Endotélio Vascular Derivado de Glândula Endócrina/fisiologia
6.
Injury ; 46(11): 2156-63, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26429103

RESUMO

OBJECTIVES: Despite the great progress in surgical treatment of lumbosacral nerve injuries caused by high-energy trauma, functional recovery remains poor and insufficient. Bone marrow mesenchymal stem cells (BMSCs), which express neurotrophic factors and can also differentiate into nerve cells, have potential as an effective alternative therapy for lumbosacral nerve defects. The aim of the present study was to evaluate the functional recovery, nerve regeneration, motor neuron survival and apoptosis after lumbosacral nerve transection in rats receiving BMSC transplantation into the chitosan conduit. METHODS: The right L4-L6 nerve roots of rats were transected and bridged with three 1-cm-long chitosan conduits, which were further injected with the BMSCs (MSC-treated group) or culture medium (DMEM group). The nerve regeneration and motor function recovery were assessed by the sciatic functional index (SFI) and analysed electrophysiologically and morphologically. RESULTS: At 6 and 12 weeks after surgery, the SFI values in MSC-treated group were significantly higher than those in DMEM group (P≤0.05). The peak amplitude of CMAP (compound muscle action potential) and nerve conduction velocity in MSC-treated group were significantly higher than that in DMEM group (P≤0.01), while the latency of CMAP onset in MSC-treated group was significantly shorter than that in DMEM group (P≤0.01). The diameter of the myelinated fibres and thickness of the myelin sheath in MSC-treated group were significantly higher than those in DMEM group (P≤0.05). There was no difference in the number of motor neurons in the anterior horn of the spinal cord at 6 weeks post-operation (P>0.05), while the number of motor neurons was significantly greater in MSC-treated group than that in DMEM group at 12 weeks post-operation (P≤0.001). The number of apoptotic cells was also significantly lower (P≤0.01). CONCLUSIONS: The results of the present study showed that BMSCs treatment improved lumbosacral nerve regeneration and motor function. In addition, our data suggested that BMSCs inhibited motor neuron apoptosis, and improved motor neuron function and survival in the anterior horn of the spinal cord.


Assuntos
Quitosana/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Nervo Isquiático/lesões , Animais , Células da Medula Óssea/fisiologia , Modelos Animais de Doenças , Regeneração Tecidual Guiada/métodos , Transplante de Células-Tronco Mesenquimais , Atividade Motora , Regeneração Nervosa , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Nervo Isquiático/fisiopatologia
7.
BMC Musculoskelet Disord ; 16: 167, 2015 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-26205233

RESUMO

BACKGROUND: Unstable pelvic fractures usually result from high-energy trauma. There are several treatment modalities available. The purpose of this study was to evaluate the clinical application of a new less invasive ilioinguinal approach combined with a minimally invasive posterior approach technique in patients with unstable pelvic fractures. We also address the feasibility, validity, and limitations of the technique. METHODS: Thirty-seven patients with unstable pelvic fractures were treated with our minimally invasive technique. The anterior pelvic ring fractures were treated with a less invasive ilioinguinal approach, and the sacral fractures were treated with a minimally invasive posterior approach. The clinical outcome was measured using the Majeed scoring system, and the quality of fracture reduction was evaluated. The patients were followed up for 13 to 60 months (mean, 24 months). RESULTS: Anatomical or near to anatomical reduction was achieved in 26 (70.3 %) of the anterior pelvic ring fractures and a satisfactory result was obtained in another 11(29.7 %). For the posterior sacral fractures, excellent reduction was obtained in 33 (89.2 %) of the fractures, with a residual deformity in the other 4 patients. One superficial wound infection and two deep vein thromboses occurred, all of which resolved with conservative treatment. The clinical outcome at one year was "excellent" in 29 patients and "good" in 8 patients (Majeed score). CONCLUSIONS: The satisfactory results showed that a reduction and fixation of unstable pelvic fractures is possible through a combination of a limited ilioinguinal approach and posterior pelvic ring fixation. We believe our method is a new and effective alternative in the management of pelvic fractures.


Assuntos
Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Ossos Pélvicos/cirurgia , Adulto , Parafusos Ósseos , Estudos de Viabilidade , Feminino , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/instrumentação , Consolidação da Fratura , Fraturas Ósseas/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Ossos Pélvicos/diagnóstico por imagem , Ossos Pélvicos/lesões , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
8.
Acta Neurochir (Wien) ; 157(1): 123-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25377383

RESUMO

BACKGROUND: There is limited knowledge about accurate segmental motor innervation of the human lower extremity skeletal muscles. The aim of the present study was to explore the truth of segmental motor innervation of the lower extremity. METHODS: Included in this study were 20 patients with unilateral fracture of the sacrum and sacral nerve injury, who underwent internal fixation and decompression of the sacral nerve in our hospital between June 2009 and January 2014. L4-S4 nerve roots of the uninjured side were stimulated during operation. Motor innervation was determined by stimulating the spinal nerves with supramaximal intensity. RESULTS: We found the gluteus medius and the gluteus maximus were both mainly innervated by L5 and S1. In addition, the nerve fibres that innervated the extensor digitorum brevis, the abductor hallucis and the flexor digitorum brevis were mainly from S2 to S3. CONCLUSIONS: Our study provides the electrophysiological mapping of the segmental anatomy of the human lower extremity muscles, which should be clinically useful in helping the diagnosis and treatment of nerve injury and neuropathies.


Assuntos
Vias Eferentes/fisiologia , Perna (Membro)/inervação , Plexo Lombossacral/fisiologia , Músculo Esquelético/inervação , Adulto , Estudos de Casos e Controles , Vias Eferentes/lesões , Feminino , Humanos , Plexo Lombossacral/lesões , Masculino , Pessoa de Meia-Idade , Sacro/lesões
9.
J Orthop Surg Res ; 9: 26, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24735864

RESUMO

INTRODUCTION: This study investigates the safety and efficacy of anterolateral (AL) osteotomy for the treatment of lateral tibial plateau fractures merged with relatively simple and intact posterolateral (PL) corner displacement and screens applicable patients. METHODS: Totally, 11 patients with lateral tibial plateau fractures involving the PL corner were included in this study. Of them, seven patients sustained their injuries from motor vehicle accidents (MVAs), three from sports and one from fall from height. All of them received open reduction and internal fixation through the AL approach. Operation time, incision length, range of motion (ROM), Hospital for Special Surgery (HSS) knee score, time of union and complications were retrospectively reviewed. Tibial plateau angle (TPA), lateral posterior slope angle (PSA) and articular step-off reduction after surgery were examined by a radiograph technique. RESULTS: Statistically, the means of operation time, incision length, ROM and follow-up period were 82 min, 11 cm, 97° and 27 months, respectively. Three patients had slight complications: superficial infection, hardware irritation and secondary valgus deformity, without severe neural or vascular injuries, which revealed the safety and efficacy of the PL treatment. The average HSS knee score was 91.2 (range 86-96). Reduction (mean TPA 87.2° and mean PSA 8.3°) was satisfactory in 10 patients, except for one patient with a radiographic articular step-off of 5 mm (case 10). CONCLUSIONS: The AL approach is safe and effective for lateral tibial plateau fractures involving the PL corner, especially for fractures merged with simple and intact PL corner displacement (depression and/or split).


Assuntos
Fixação Interna de Fraturas/métodos , Osteotomia/métodos , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/cirurgia , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
10.
Chin J Traumatol ; 16(4): 237-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23910678

RESUMO

Guide wire plays an important role in the fixation of femoral neck fracture with dynamic hip screw (DHS). Breakage of a guide wire during operation is a very rare condition. We met such a dilemma in DHS fixation of a 54-year-old male patient who sustained Garden type IV fracture of the right femoral neck. The distal end of the guide wire broke and was entrapped in the fractured femoral neck. We tried to get the broken part out by a cannulated drill. Reaming was started with the cannulated drill slowly rotating around the guide K-wire until the reamer fully contained the target under fluoroscope. A bone curette was used to get the broken wire out but failed, so we had to use the cannuated drill to dredge this bone tunnel. Finally the broken wire end was taken out, mixed with blood and bone fragments. Through the existing drilling channel, DHS fixation was easily finished. The patient had an uneventful recovery without avascular necrosis of femoral head or non-union of the fracture at one year's follow-up. A few methods can be adopted to deal with the broken guide wire. The way used in our case is less invasive but technically challenging. When the guide wire is properly positioned, this method is very practical and useful.


Assuntos
Fios Ortopédicos/efeitos adversos , Remoção de Dispositivo , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas do Colo Femoral/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia
11.
Zhong Yao Cai ; 36(9): 1437-40, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24620688

RESUMO

OBJECTIVE: To study the phenolic derivatives from Wisteria sinensis. METHODS: From the petroleum ether extraction of 95% alcohol permeating extraction, 12 compounds were isolated and purified with silica gel and Sephadex LH-20 column chromatography. Their structures were determined on the basis of physicochemical properties and spectroscopic analysis. RESULTS: They were identified as formononetin (1), (3S)-vestitol (2), (6aS, 11aS)-medicarpin (3), (-+/-) isoduartin (4), (3S)-7,1'-dihydroxy-8,3'-dimethoxyisoflavan (5), isosakuranetin (6), p-hydroxy-benzaldehyde (7), 11b-hydroxy-11b, 1-dihydromedicarpin (8), 3-hydroxy-medicarpin (9), syringaresinol (10), 5-hydroxy-7-methoxychromone (11), vanillin (12). CONCLUSION: All the compounds are isolated from this plant for the first time.


Assuntos
Fenóis/isolamento & purificação , Caules de Planta/química , Wisteria/química , Cromatografia em Camada Fina , Etanol/química , Flavonoides/química , Flavonoides/isolamento & purificação , Isoflavonas/química , Isoflavonas/isolamento & purificação , Estrutura Molecular , Fenóis/química
12.
Zhong Yao Cai ; 35(8): 1246-50, 2012 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-23320355

RESUMO

OBJECTIVE: To study the triterpenoids constituents from Wisteria sinensis Sweet Caulis. METHODS: The compounds were beta-solated and purified with silica gel and Sephadex LH-20 column chromatography from the petroleum ether extract. Their structures were determined on the basis of physicochemical properties and spectroscopic analysis. RESULTS: They were identified as beta-sitosterol palmitate (1), alpha-spinasterol (2), (22E, 24R)-5alpha, 8alpha-epidioxy-ergosta-6, 22-dien-3beta-ol (3), (22E, 24R)-ergosta-5, 7, 22-trien-3beta-ol (4), (22E, 24R) -ergosta-7, 22-dien-3beta-ol (5), 11alpha, 12alpha-oxidotaraxerol (6), lupeol (7), betulinic acid (8), 22-oxo-3beta, 24-dihydroxyolean-12-ene (9), 2alpha, 3beta, 23-trihydroxyolean-12-ene (10), soyasapogenol E (11), 3alpha, 21beta-dihydroxy-olean-12-ene (12). CONCLUSION: Compounds 1 - 12 are isolated from this plant for the first time.


Assuntos
Caules de Planta/química , Triterpenos/isolamento & purificação , Wisteria/química , Etanol/química , Estrutura Molecular , Sitosteroides/química , Sitosteroides/isolamento & purificação , Estigmasterol/análogos & derivados , Estigmasterol/química , Estigmasterol/isolamento & purificação , Triterpenos/química
13.
Contraception ; 84(6): 609-14, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22078190

RESUMO

BACKGROUND: The aim of this study is to explore the effect of first-trimester mifepristone-induced abortion on vaginal bleeding in subsequent pregnancy. STUDY DESIGN: This observational cohort study was conducted during 1998-2001 at antenatal clinics in Beijing, Chengdu, and Shanghai, China. The study enrolled 4,931 women with one previous mifepristone-induced abortion, 4,925 women with no history of induced abortion, and 4,800 women with one previous surgical abortion and followed them through pregnancy and childbirth. RESULTS: The rates of vaginal bleeding in pregnant women with a history of medical abortion, no abortion, and surgical abortion were 16.5%, 13.9%, and 17.3%, respectively. The women with medical abortion had a higher risk (adjusted relative risk (aRR)=1.17, 95% confidence interval (CI): 1.07, 1.29) of vaginal bleeding compared with those with no abortion but similar risk to prior surgical abortion. When the correlation between medical abortion and vaginal bleeding was examined by period, increased risk was observed only in the early period (<16 gestational weeks) (aRR=1.25, 95% CI: 1.12, 1.39). The comparison between subgroups of medical abortion and no abortion showed that the observed risks increased particularly in those with abortion at gestational age ≤ 7 weeks (aRR=1.33, 95% CI: 1.18, 1.49), those followed by a postabortion curettage (aRR=1.58, 95% CI: 1.37, 1.84) or complications (aRR=1.99, 95% CI: 1.67, 2.37). There was no difference between women with medical abortion and women with surgical abortion in the occurrence of vaginal bleeding for either period. CONCLUSIONS: One previous mifepristone-induced abortion increased the risk of vaginal bleeding in early gestation period of subsequent pregnancy compared with no abortion, especially if abortion occurred before 7 weeks of gestation and was followed by a curettage or complications.


Assuntos
Abortivos Esteroides/efeitos adversos , Aborto Induzido/efeitos adversos , Mifepristona/efeitos adversos , Complicações Cardiovasculares na Gravidez/etiologia , Hemorragia Uterina/etiologia , Aborto Induzido/métodos , Adulto , China/epidemiologia , Estudos de Coortes , Curetagem/efeitos adversos , Feminino , Seguimentos , Humanos , Gravidez , Complicações na Gravidez/fisiopatologia , Complicações Cardiovasculares na Gravidez/induzido quimicamente , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Estudos Prospectivos , Risco , Inquéritos e Questionários , Hemorragia Uterina/induzido quimicamente , Adulto Jovem
14.
Res Microbiol ; 161(7): 556-64, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20594941

RESUMO

Sinorhizobium meliloti can live as a saprophyte in soil or as a nitrogen-fixing symbiont inside the root nodule cells of alfalfa and related legumes by utilizing different organic compounds as its carbon source. Here we have identified the matPQMAB operon in S. meliloti 1021. Within this operon, matP, matQ and the M region of the fused gene matMA encode an extracytoplasmic solute receptor, a small transmembrane protein and a large transmembrane protein, consisting of three components of the tripartite ATP-independent periplasmic (TRAP) transporter for malonate transport. The A region of the fused gene matMA and matB encode malonate-metabolizing enzymes, malonyl-CoA decarboxylase and malonyl-CoA synthetase. The null mutant of each matPQMAB gene is unable to grow on M9 minimal medium containing malonate as the sole carbon source. However, these mutants can induce the formation of efficient nitrogen-fixing root nodules on alfalfa. The matPQMAB operon is expressed in free-living bacterial cells and symbiotic bacterial cells from infection threads and root nodules. The GntR family transcriptional regulator, GtrA, specifically binds the promoter of the matPQMAB operon, positively regulating its expression. Moreover, the matPQMAB can be transcriptionally induced by malonate. These results suggested that a C(3)-dicarboxylic acid TRAP transporter is responsible for malonate transport in S. meliloti.


Assuntos
Transportadores de Ácidos Dicarboxílicos/genética , Regulação Bacteriana da Expressão Gênica , Malonatos/metabolismo , Óperon , Sinorhizobium meliloti/metabolismo , Fatores de Transcrição/metabolismo , Aldeído Oxirredutases/genética , Aldeído Oxirredutases/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Carboxiliases/genética , Carboxiliases/metabolismo , Coenzima A Ligases/genética , Coenzima A Ligases/metabolismo , Transportadores de Ácidos Dicarboxílicos/metabolismo , Genes Bacterianos , Transporte de Íons , Medicago sativa/microbiologia , Fixação de Nitrogênio/genética , Plasmídeos , Reação em Cadeia da Polimerase , RNA Bacteriano , Sinorhizobium meliloti/genética , Sinorhizobium meliloti/crescimento & desenvolvimento , Simbiose/genética , Fatores de Transcrição/genética
15.
J Integr Plant Biol ; 52(7): 639-52, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20590994

RESUMO

ROPs (Rho-related GTPases of plants) are small GTPases that are plant-specific signaling proteins. They act as molecular switches in a variety of developmental processes. In this study, seven cDNA clones coding for ROP GTPases have been isolated in Medicago truncatula, and conserved and divergent domains are identified in these predicted MtROP proteins. Phylogenetic analysis has indicated that MtROPs are distributed into groups II, III, IV but group I. MtROP genes are expressed in various tissues at different levels. A quantitative reverse transcription PCR analysis indicated that these MtROP genes have different expression profiles in the roots in response to infection with rhizobia. The expression of MtROP3, MtROP5 and MtROP6 are increased, as the expression of Nod factor or rhizobial-induced marker genes--NFP, Rip1 and Enod11; MtROP10 has showed enhanced expression at a certain post-inoculation time point. No significant changes in MtROP7 and MtROP9 expression have been detected and MtROP8 expression is dramatically decreased by about 80%-90%. Additionally, ROP promoter-GUS analysis has showed that MtROP3, MtROP5 and MtROP6 have elevated expression in transgenic root hairs after rhizobial inoculation. These results might suggest a role for some ROP GTPases in the regulation of early stages during rhizobial infection in symbiosis.


Assuntos
Proteínas de Ligação ao GTP/fisiologia , Regulação da Expressão Gênica de Plantas , Medicago truncatula/genética , Medicago truncatula/microbiologia , Proteínas de Plantas/fisiologia , Simbiose/fisiologia , Sequência de Aminoácidos , Proteínas de Ligação ao GTP/química , Proteínas de Ligação ao GTP/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/microbiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/microbiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rhizobium/genética , Homologia de Sequência de Aminoácidos , Sinorhizobium meliloti/crescimento & desenvolvimento , Sinorhizobium meliloti/fisiologia , Simbiose/genética
16.
Biol Reprod ; 83(4): 656-62, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20610805

RESUMO

Apoptosis is very common during various stages of mammalian germ cell development and differentiation, and the BCL2 gene is one of the most important apoptotic regulators. Although its genetic variants are reported to be involved in cancers and autoimmune diseases, little information is available regarding BCL2 polymorphisms in male spermatogenesis. In the present study, single nucleotide polymorphisms (SNPs) in coding regions of the BCL2 gene were examined in a hospital-based, case-control study including 198 infertile patients with idiopathic azoospermia and 183 fertile controls. Subsequently, a functional study was conducted for comparison of paclitaxel-induced cytotoxicity and apoptosis between the BCL2 variant and the wild type in vitro. Three SNPs were found in exon 2--A21G (rs1801018), G127A (rs1800477), and C300T (rs61733416)--with the latter first reported in the Han-Chinese population. The frequency of G127A (GA+AA) genotype was significantly lower in azoospermic, infertile men compared to the age-matched controls (P = 0.01). This genotype may confer a lower risk of azoospermia (adjusted odd ratio [OR] = 0.448, 95% confidence interval = 0.226-0.889). In addition, HeLa cells expressing the BCL2 Ala43Thr (G127A), similar to the control cells, were more sensitive to paclitaxel-induced cytotoxicity and apoptosis than those expressing wild-type BCL2. Consistently, the cleaved PARP and p-BCL2 proteins were subsequently increased after paclitaxel treatment, as also predicted by the bioinformatics analysis. Considering the decreased antiapoptotic function of BCL2, these results suggest that the Ala43Thr variant is associated with protection against azoospermia in the Han-Chinese population.


Assuntos
Azoospermia/genética , Genes bcl-2 , Espermatogênese/genética , Adulto , Antineoplásicos Fitogênicos/farmacologia , Apoptose/genética , Apoptose/fisiologia , Azoospermia/fisiopatologia , Estudos de Casos e Controles , Sobrevivência Celular/efeitos dos fármacos , Distribuição de Qui-Quadrado , China , DNA/química , DNA/genética , Variação Genética , Genótipo , Células HeLa , Humanos , Immunoblotting , Masculino , Paclitaxel/farmacologia , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Espermatogênese/fisiologia , Transfecção
17.
Paediatr Perinat Epidemiol ; 24(2): 125-30, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20415767

RESUMO

To evaluate the impact of mifepristone-induced abortion (MA) on the duration of third stage labour in a subsequent pregnancy, an observational cohort study was conducted from 1998 to 2001 at antenatal clinics in Shanghai, Beijing and Chengdu, China. A total of 4925 pregnant women with no history of induced abortion (NA) and 4931 pregnant women with one previous MA were enrolled and followed until delivery. Of these, 5139 women who delivered singletons vaginally were used in the present analyses, including 2614 with NA and 2525 with a history of MA. Maternal characteristics, labour duration and other obstetric and gynaecological information were obtained. The incidence rates of prolonged third stage of labour were 1.55% and 1.49% in NA and MA, respectively. After adjusting for age at delivery, maternal education, maternal occupation, area of residence, duration of gestational, type of delivery and pregnancy-induced hypertension, MA was not associated with the risk of prolonged third stage of labour (odds ratios = 0.92, 95% confidence interval 0.58, 1.44). Subgroup analysis of women with MA showed similar results regardless of gestational age at abortion, woman's age at abortion, subsequent curettage/complications and the interpregnancy interval. In conclusion, the data did not provide evidence that one MA was associated with the risk of prolonged third stage of labour in a subsequent pregnancy in primiparae.


Assuntos
Abortivos Esteroides/efeitos adversos , Aborto Induzido/efeitos adversos , Terceira Fase do Trabalho de Parto/fisiologia , Exposição Materna/efeitos adversos , Mifepristona/efeitos adversos , Adulto , Fatores Etários , China , Estudos de Coortes , Feminino , Humanos , Razão de Chances , Gravidez , Resultado da Gravidez , Fatores de Tempo , Adulto Jovem
18.
J Spinal Cord Med ; 32(1): 79-85, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19264053

RESUMO

BACKGROUND/OBJECTIVE: To study the effectiveness of knee-tendon to bladder artificial reflex arc in dogs. METHODS: In 6 beagles, the proximal end of the right L5 anterior motor root and the distal end of the right S2 anterior root were anastomosed to build a knee-tendon to bladder reflex, whereas the right L5 posterior sensory root was kept intact. Action potential (AP) curves and electromyograms (EMGs) of the detrusor muscle, the intravesical pressure, horseradish peroxidase (HRP)-labeled neurons, and the passing rates of myelinic nerve fibers were calculated to evaluate its feasibility. RESULTS: AP curves and EMG detected in all 6 dogs were similar to those of the control. Six and 18 months after surgery, the means for bladder contraction induced by percussion of the right knee-tendon were 38 +/- 27% and 62 +/- 5% that of the normal control, respectively. The mean duration times induced by percussion of the right knee-tendon at 6 and 18 months after surgery were 51 +/- 37% and 84 +/- 12% that of the normal control, respectively. HRP retrograde tracing and neurohistologic observation indicated the feasibility of the artificial reflex arc. CONCLUSIONS: Our data showed the effectiveness of bladder innervation below the level of spinal cord injury producing urination by knee-tendon to bladder reflex contractions, and therefore, might provide a new clinical approach for restoring bladder function in individuals with paraplegia.


Assuntos
Articulação do Joelho/inervação , Reflexo/fisiologia , Traumatismos da Medula Espinal/complicações , Tendões/inervação , Doenças da Bexiga Urinária/etiologia , Bexiga Urinária/inervação , Potenciais de Ação/fisiologia , Anastomose Cirúrgica , Animais , Pressão Sanguínea/fisiologia , Modelos Animais de Doenças , Cães , Eletromiografia , Seguimentos , Peroxidase do Rábano Silvestre , Músculo Esquelético/fisiopatologia , Traumatismos da Medula Espinal/cirurgia
19.
Hum Reprod ; 24(2): 315-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19054774

RESUMO

BACKGROUND: The aim of the study was to explore the effect of first-trimester mifepristone-induced abortion (MA) on placental complications in subsequent pregnancy. METHODS: Two cohorts of nulliparous pregnant women were recruited in China during early pregnancy, one with a history of one MA and the other with no abortion (NA). Women were followed up until delivery. RESULTS: The incidence proportions of abruptio placenta, placenta previa, placenta accreta and retained placenta in the MA group (4673) and NA group (4690) were, respectively, 0.5 and 0.3, 0.8 and 0.9, 0.5 and 0.5, and 0.7 and 0.8% (all differences non-significant). After adjustment for center, age, education, occupation, residence, income, BMI and type of delivery, the incidence rates of placenta previa, accreta and retained placenta in the MA and NA groups showed no significant differences. The risk of abruptio placenta in women with a MA was nearly double that of women with no abortion, although this apparent increased risk was not statistically significant. Furthermore, this increased risk of abruptio placenta was found only in those with a gestational age >6 weeks at abortion (aOR: 2.46; 95% CI: 1.00-6.04), a curettage after abortion (aOR: 3.00; 95% CI: 1.25-7.20) or a longer inter-pregnancy interval (P-value for trend: 0.022). CONCLUSIONS: Mifepristone-induced abortion itself is not associated with placental complications in subsequent pregnancy, but other factors related to medical abortion-such as a gestational age >6 weeks at abortion, a curettage after abortion, and a longer interpregnancy interval-may increase the risk of abruptio placenta.


Assuntos
Abortivos Esteroides/efeitos adversos , Aborto Induzido/efeitos adversos , Mifepristona/efeitos adversos , Doenças Placentárias/etiologia , Estudos de Coortes , Feminino , Humanos , Incidência , Doenças Placentárias/epidemiologia , Gravidez , Fatores de Risco
20.
Nan Fang Yi Ke Da Xue Xue Bao ; 28(7): 1114-6, 2008 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-18676240

RESUMO

OBJECTIVE: To investigate the psychological stress in the survivors of the May 12, 2008 Wenchuan earthquake transferred to Guangzhou for treatment, and explore the association between the psychological stress and the physical injuries related to the earthquake to promote both the physical and psychological recoveries of the survivors. METHODS: Fifty-five earthquake survivors, including 27 with 28 without physical injuries, were transferred in our hospital 1 week after the earthquake. The Posttraumatic Stress Disorder (PTSD) Checklist-Civilian version (PCL-C) and the Self Reporting Questionnaire (SRQ) were used to investigate the psychological stress in these survivors. RESULTS: The earthquake caused serious psychological stress in these survivors, and 43.63% of the survivors had high PCL-C scores (50 or above) and 78.18% had high SRQ scores (over 7), with 41.82% having high scores for both PCL-C and SRQ. The survivors with physical injuries generally had high PCL-C and SRQ scores (49.780-/+14.503 and 12.110-/+4.619, respectively), which, however, were not statistically different from the scores of the survivors without injuries (44.460-/+13.206 and 10.460-/+5.000, respectively, P>0.05). The injured survivors showed high scores for the subscales of persistent avoidance symptoms and of anger and irritability, in which the item scores for "efforts to avoid activities or places that arouse recollections of the earthquake" and "feeling of detachment or estrangement from others" were significantly different between the survivor with physical injuries and those without (P=0.034 and 0.018, respectively). CONCLUSION: The Wenchuan earthquake causes serious psychological stress in the survivors, and the wounded are more inclined to have persistent avoidance symptoms and enhanced irritability. In addition to the care of the physical injuries, psychological counseling and social support may help ameliorate the psychological trauma in the survivors and reduce the incidence of PTSD.


Assuntos
Terremotos , Estresse Psicológico/psicologia , Sobreviventes/psicologia , Ferimentos e Lesões/psicologia , Adolescente , Adulto , Idoso , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
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