RESUMO
BACKGROUND: Scenedesmus obliquus belongs to green microalgae and is widely used in aquaculture as feed, which is also explored for lipid production and bioremediation. However, genomic studies of this microalga have been very limited. Cell self-flocculation of microalgal cells can be used as a simple and economic method for harvesting biomass, and it is of great importance to perform genome-scale studies for the self-flocculating S. obliquus strains to promote their biotechnological applications. RESULTS: We employed the Pacific Biosciences sequencing platform for sequencing the genome of the self-flocculating microalga S. obliquus AS-6-11, and used the MECAT software for de novo genome assembly. The estimated genome size of S. obliquus AS-6-11 is 172.3 Mbp with an N50 of 94,410 bp, and 31,964 protein-coding genes were identified. Gene Ontology (GO) and KEGG pathway analyses revealed 65 GO terms and 428 biosynthetic pathways. Comparing to the genome sequences of the well-studied green microalgae Chlamydomonas reinhardtii, Chlorella variabilis, Volvox carteri and Micractinium conductrix, the genome of S. obliquus AS-6-11 encodes more unique proteins, including one gene that encodes D-mannose binding lectin. Genes encoding the glycosylphosphatidylinositol (GPI)-anchored cell wall proteins, and proteins with fasciclin domains that are commonly found in cell wall proteins might be responsible for the self-flocculating phenotype, and were analyzed in detail. Four genes encoding both GPI-anchored cell wall proteins and fasciclin domain proteins are the most interesting targets for further studies. CONCLUSIONS: The genome sequence of the self-flocculating microalgal S. obliquus AS-6-11 was annotated and analyzed. To our best knowledge, this is the first report on the in-depth annotation of the S. obliquus genome, and the results will facilitate functional genomic studies and metabolic engineering of this important microalga. The comparative genomic analysis here also provides new insights into the evolution of green microalgae. Furthermore, identification of the potential genes encoding self-flocculating proteins will benefit studies on the molecular mechanism underlying this phenotype for its better control and biotechnological applications as well.
Assuntos
Chlorella , Microalgas , Scenedesmus , Biomassa , Glicolatos , Microalgas/genéticaRESUMO
A new method was developed to synthesize N(2)-alkyl-substituted 1,2,3-triazole through N-iodosuccinimide (NIS) mediated iodofuctionalization reaction of the alkene group with bi-, mono-, and unsubstituted NH-1,2,3-triazoles. The favored N-1 type hydrogen bond between the iodonium ion intermediate and 1,2,3-triazole was supposed to be generated, which gave the desired N(2)-alkyl triazole with a high N(2)-selectivity.
RESUMO
A new method was developed to synthesize polyfunctionalized dihydrofuran and tetrahydrofuran derivatives from the three-component [2 + 2 + 1] cycloaddition of the diazoesters with aryl/alkenyl aldehydes and alkyne/olefin dipolarophiles by using a Ag(I) N-heterocyclic carbene complex as the catalyst. A carbonyl ylide intermediate was generated, which undertook an endo-type 1,3-dipolar cycloaddition to provide the desired dihydro-/tetrahydrofurans in high regio- and diastereoselectivities by using α-aryl or α-alkenyl diazoesters.
RESUMO
Studies have proved an increased expression of tumor necrosis factor alpha (TNF-α) in estrogen deficiency animals, and TNF-α also plays a role in inflammation and neuropathic pain. This study aimed to explore the relationship between TNF-α and ovariectomy induced hyperalgesia. 36 female Sparague-Dawley were included, estrogen depletion models were established by ovariectomy. Then infliximab (a TNF-α blocker) was administrated to the ovariectomized rats for 8 weeks. Pain behavioral tests were performed once a week. The bone mineral density (BMD), serum estradiol and TNF-α level were determined at the 8th week after ovariectomy. The expression of TNF-α in lumbar 5 dorsal root ganglions (L5 DRGs) was examined by immunofluorescence method. Significant hyperalgesia to mechanical and thermal stimuli in groups Ovx-1 and Ovx-2 was observed 1 week after the operation. After treated with infliximab, the pain threshold of Ovx-2 was partially restored, although still lower than the Sham group. The serum TNF-α level of Ovx-1 was significantly higher than Sham and Ovx-2. TNF-α immunofluorescence indicated a significant increase in the expression of TNF-α at L5 DRGs in group Ovx-1 when compared with groups Sham and Ovx-2. The BMD of group Ovx-2 was significantly higher than group Ovx-1 and lower than group Sham. In conclusion, TNF-α plays an important role in estrogen deficiency induced mechanical and thermal hyperalgesia, and DRG may be one site on which TNF-α acts to cause hyperalgesia. Blocking the effect of TNF-α could partially alleviate the estrogen deficiency induced hyperalgesia in rats. Thus, TNF-α may contribute to chronic pain in postmenopausal women.
Assuntos
Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Hiperalgesia , Ovariectomia/efeitos adversos , Fator de Necrose Tumoral alfa/metabolismo , Absorciometria de Fóton , Análise de Variância , Animais , Peso Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Modelos Animais de Doenças , Estradiol/farmacologia , Feminino , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Hiperalgesia/metabolismo , Infliximab , Medição da Dor , Limiar da Dor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacosRESUMO
OBJECTIVE: To analyze the clinical significance of postoperative back muscle exercises after percutaneous vertebroplasty for spinal osteoporotic compression fracture patients. DESIGN: Clinical randomized controlled trials of parallel group nonpharmacologic study. SETTING: Patients practised back muscle exercises in the spinal surgery department, rehabilitation department and at their residences. SUBJECTS: Osteoporotic compression fracture patients who had undergone percutaneous vertebroplasty and processed sufficient muscle strength to participate in the training were studied. INTERVENTIONS: Patients were randomized into two groups, which were titled A and B. General postoperation therapy, including antiosteoporotic medications and education, was offered to all patients. Group B patients received additional systematic back muscle exercise. MAIN MEASURES: Both Oswestry Disability Index (ODI) and visual analogue scale (VAS) were recorded preoperatively and postoperatively at three-day, one-month, six-month, one-year and two-year follow-up. RESULTS: From January 2006 to January 2009, a total of 82 patients were assessed for eligibility, 60 patients were enrolled and randomized into two groups. Forty-two (70%) patients (20 of 30 in Group A and 22 of 30 in Group B) were successfully followed-up for two years. Systematic back muscle exercises resulted in a significant advantage in both measurements. The ODI of Group B was significantly better than Group A at the six-month, one-year and two-year follow-ups (P < 0.05). The pain level of Group B was significantly lower than in Group A at the one- and two-year follow-ups (P < 0.05). At the end of our study, the mean (SD) of the ODI in Groups A and B were 39.1 (9.14) and 23.4 (5.62); the mean (SD) of the VAS in Groups A and B were 3.4 (1.15) and 2.1 (0.84), respectively. CONCLUSIONS: Our findings suggest that the benefit of the exercises required at least six months to be observed; however, the favourable effects could last for two years. Therefore, systematic back muscle exercise should be recommended as one of the treatment guidelines for postpercutaneous vertebroplasty patients.
Assuntos
Terapia por Exercício , Fraturas por Compressão/terapia , Dor Lombar/terapia , Fraturas por Osteoporose/terapia , Fraturas da Coluna Vertebral/terapia , Vertebroplastia , Idoso , Feminino , Humanos , Dor Lombar/etiologia , Masculino , Músculo Esquelético/fisiologia , Medição da DorRESUMO
Objective: Postmenopausal osteoporosis (PMOP), a chronic systemic metabolic disease prevalent in middle-aged and elderly women, heavily relies on bone mineral density (BMD) measurement as the diagnostic indicator. In this study, we investigated serum microRNAs (miRNAs) as a possible screening tool for PMOP. Methods: This investigation recruited 83 eligible participants from 795 community-dwelling postmenopausal women between June 2020 and August 2021. The miRNA expression profiles in the serum of PMOP patients were evaluated via miRNA microarray (six PMOP patients and four postmenopausal women without osteoporosis (n-PMOP) as controls). Subsequently, results were verified in independent sample sets (47 PMOP patients and 26 n-PMOP controls) using quantitative real-time PCR. In addition, the target genes and main functions of the differentially expressed miRNAs were explored by bioinformatics analysis. Results: Four highly expressed miRNAs in the serum of patients (hsa-miR-144-5p, hsa-miR-506-3p, hsa-miR-8068, and hsa-miR-6851-3p) showed acceptable disease-independent discrimination performance (area under the curve range: 0.747-0.902) in the training set and verification set, outperforming traditional bone turnover markers. Among four key miRNAs, hsa-miR-144-5p is the only one that can simultaneously predict changes in BMD in lumbar spine 1-4, total hip, and femoral neck (ß = -0.265, p = 0.022; ß = -0.301, p = 0.005; and ß = -0.324, p = 0.003, respectively). Bioinformatics analysis suggested that the differentially expressed miRNAs were targeted mainly to YY1, VIM, and YWHAE genes, which are extensively involved in bone metabolism processes. Conclusions: Bone-metabolism-related serum miRNAs, such as hsa-miR-144-5p, hsa-miR-506-3p, hsa-miR-8068, and hsa-miR-6851-3p, can be used as novel biomarkers for PMOP diagnosis independent of radiological findings and traditional bone turnover markers. Further study of these miRNAs and their target genes may provide new insights into the epigenetic regulatory mechanisms of the onset and progression of the disease.
RESUMO
PURPOSE: To investigate: (1) the risk factors for radiologic cranial adjacent segment degeneration (ASD) after single-segment PLIF at the same level, and (2) the impact of the ASD on the clinical outcomes. METHODS: From October 2004 to May 2009, 109 patients who underwent PLIF for degenerative instability at L4/5 and have more than 2 years follow-up were studied retrospectively. We measured the preoperative bone mineral density (BMD), lumbar lordosis, the lumbosacral joint angle, the lumbar inclination, the height and the dynamic angulation of the intervertebral space at the fused segments and the upper adjacent segment, the sliding displacement between L3 and L4. Clinical outcomes were evaluated using the Japanese Orthopedic Association (JOA) score and the Oswestry Disability Index (ODI). Patients were divided into two groups according to the progression of L3-L4 degeneration: Group A without progression of L3-L4 degeneration, Group B with progression of L3-L4 degeneration. Clinical outcomes and radiologic measurement index between the two groups were compared, and the risk factors for progression of L3-L4 degeneration were analyzed. The correlation between clinical outcomes and progression of L3-L4 degeneration were also investigated. RESULTS: There were 11 patients (22%) classified into Group A. No significant difference was found between the two groups in terms of the lordosis angle at L1 and S1, the laminar inclination at L3, the pre-existing L3-L4 disk degeneration, the lordosis angle of L4-L5, the lumbosacral joint angle and preoperative BMD (P > 0.05). Significant differences were found between the two groups in age. No significant difference was found between the two groups in the ODI and the JOA score at the final follow-up (P > 0.05). CONCLUSION: Radiologic degeneration of the cranial adjacent segment after single-segment PLIF did not significantly correlate with clinical outcomes. Age was a risk factor for radiologic degeneration, however, there was no significant correlation between degeneration and preoperative radiologic factors and bone mineral density (BMD).
Assuntos
Progressão da Doença , Vértebras Lombares/diagnóstico por imagem , Doenças da Coluna Vertebral/diagnóstico por imagem , Fusão Vertebral/efeitos adversos , Adulto , Idoso , Densidade Óssea , Feminino , Seguimentos , Humanos , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Fatores de Risco , Doenças da Coluna Vertebral/cirurgia , Resultado do TratamentoRESUMO
The addition of alkynylmagnesium chlorides to N-tert-butanesulfinyl imines proceeded with a remarkably high diastereoselectivity (dr > 13:1, mostly diastereopure), and with a general scope of both reaction partners. The high dr translated into simplified purification and higher optical purity for the synthesis of a wide array of chiral alpha-branched amines. The alkyne functionality also provides a multitude of opportunities for further synthetic transformations. The short asymmetric synthesis of (+)-angustureine 7 and (-)-cuspareine 10 was realized with use of this approach.
Assuntos
Alcinos/química , Aminas/química , Iminas/síntese química , Cloreto de Magnésio/química , Compostos de Sulfidrila/síntese química , Iminas/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Estereoisomerismo , Compostos de Sulfidrila/químicaRESUMO
Amorphallus konjac corms are important agriculture products in Yichang, Hubei Province, China. The Erwinia carotovora infected Amorphallus konjac corms are processed to food as normal corms. The contents of elements and L: -Proline in the normal and infected Amorphallus konjac corms are analyzed for food safety. Even growing in the almost same soil condition, the contents of Pb, Cd, Mn and L: -Proline in infected corms are significantly higher than those of normal corms (show data as suggestion by peers). Our study suggested that the infected corms are not suitable for food purpose.
Assuntos
Amorphophallus/crescimento & desenvolvimento , Chumbo/análise , Pectobacterium carotovorum/isolamento & purificação , Doenças das Plantas/microbiologia , Poluentes do Solo/análise , Amorphophallus/química , Amorphophallus/microbiologia , China , Produtos Agrícolas/química , Produtos Agrícolas/microbiologia , Produtos Agrícolas/normas , Monitoramento Ambiental , Análise de Alimentos , Prolina/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Solo/análise , Solo/normasRESUMO
An allenylidene Au(i) catalyst based on triazolylidene moieties, featuring the high σ-donating ability (comparable to that of other NHC ligands) and largely enhanced π-accepting ability of its ligand, was developed for the first time. As compared with the extant gold complexes such as IPrAuCl, Ph3PAuCl and (PhO)3PAuCl, these allenylidene Au(i) catalysts exhibited superior catalytic activities in the gold-catalyzed Nazarov reaction of aryl enones.
RESUMO
BACKGROUND: As an irrigant, an antiseptic, and a hemostatic agent, hydrogen peroxide (H2O2) is widely used in surgical treatment, but it has been surrounded by persistent controversy. Fatal or near-fatal embolic events caused by H2O2 have been reported sporadically in spine surgery. CASE DESCRIPTION: In this report, we present an 87-year-old man who underwent lumbar instrumentation removal and debridement consequent to surgical site infection in a prone position. H2O2 was used to irrigate the infected screw tracks and surrounding tissues during the procedures. Soon after irrigation, the patient suddenly developed tachycardia, hypotension, and rapid oxygen desaturation, followed by bradycardia. Transesophageal echocardiography indicated gas embolism. After prompt first aid treatment, the patient's condition improved and the gas embolus disappeared within a few minutes without any evidence of organ embolism. CONCLUSIONS: Spine surgeons should reconsider the pending results of using H2O2 during surgery. Prolonged prone positioning and semiclosed cavities may increase the risk of gas embolism. An early diagnosis and timely intervention may be the key measures to prevent the occurrence of fatal consequences caused by gas embolism.
Assuntos
Anti-Infecciosos Locais/efeitos adversos , Embolia Aérea/etiologia , Peróxido de Hidrogênio/efeitos adversos , Coluna Vertebral/cirurgia , Idoso de 80 Anos ou mais , Desbridamento , Remoção de Dispositivo , Ecocardiografia Transesofagiana , Embolia Aérea/diagnóstico por imagem , Embolia Aérea/terapia , Humanos , Complicações Intraoperatórias/diagnóstico , Complicações Intraoperatórias/terapia , Masculino , Decúbito Ventral , Irrigação Terapêutica/efeitos adversosRESUMO
Retinal (C20) and the C25 and C30 homologues were compared as radical scavengers together with their C22, C27, and C32 homologues linked with daidzein through a B'3 (isoflavonoid) to oxo-carbon (aldehyde) covalent bond. Oxidation potential in acetonitrile determined by cyclic voltammetry and ionization potential calculated by density functional theory for the aldehydes and dyads (conjugates), of which the two longer are new, decreased linearly with the wavenumber for absorption maximum. The logarithm of the second-order rate constant for scavenging of the ABTSâ¢+ increased linearly with decreasing oxidation potential suggesting that longer conjugation in the antioxidant increases the rate of electron transfer. A similar linear free energy relationship was found for the rate of scavenging DPPHâ¢, including daidzein, which may indicate involvement of hydrogen atom transfer from an isoflavonoid phenol. Prediction of radical scavenging efficiency from visible absorption spectra was demonstrated with the perspective of rational design of bifunctional amphiphilic antioxidants.
RESUMO
BACKGROUND: Three-column osteotomies were developed to treat severe spinal deformities but result in high neurologic complications and require further risk stratification. The present study investigated whether the combination of spinal cord function classification (SCFC) and deformity angular ratio (DAR) could further stratify the neurologic risks in the surgical correction of severe and stiff kyphoscoliosis. METHODS: The patients with kyphoscoliosis who had undergone posterior 3-column osteotomies at the spinal cord level were reviewed. Using our SCFC system, the preoperative neurologic function (type A, B, or C) was classified. The sagittal DAR (S-DAR), coronal, and total DARs were calculated. Intraoperative monitoring events and new neurologic deficits (NNDs) postoperatively were documented and analyzed using the SCFC and DAR or both combined. RESULTS: The NND rates increased significantly from type A to C (P = 0.000) and increased exponentially with an increase in S-DAR in types B and C but not type A. They also increased exponentially with aggravation of the SCFC in the medium and high but not low S-DAR group. All NNDs had recovered at 3 months for type A and most had recovered at 6 months for type B or C. CONCLUSIONS: The NNDs in type A SCFC usually experienced better recovery even with high S-DARs. Type B SCFC with an S-DAR >20° and type C SCFC with any S-DAR resulted in significantly greater intra- and postoperative neurologic risks. The combination of SCFC and S-DAR can further stratify the intra- and postoperative neurologic risks with these procedures.
Assuntos
Cifose/cirurgia , Escoliose/cirurgia , Doenças da Medula Espinal/etiologia , Medula Espinal/fisiologia , Adolescente , Adulto , Idoso , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Criança , Eletromiografia , Potencial Evocado Motor/fisiologia , Potenciais Somatossensoriais Evocados/fisiologia , Feminino , Humanos , Complicações Intraoperatórias/etiologia , Cifose/patologia , Cifose/fisiopatologia , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Osteotomia/métodos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Estudos Retrospectivos , Fatores de Risco , Escoliose/patologia , Escoliose/fisiopatologia , Medula Espinal/cirurgia , Doenças da Medula Espinal/fisiopatologia , Adulto JovemRESUMO
BACKGROUND: The differentiation between intracranial atherosclerotic stenosis (ICAS) and intracranial embolism as the immediate cause of acute ischemic stroke requiring endovascular therapy is important but challenging. In cases of ICAS, we often observe a phenomenon we call the microcatheter "first-pass effect," which is temporary blood flow through the occluded intracranial artery when the angiographic microcatheter is initially advanced through the site of total occlusion and immediately retrieved proximally. OBJECTIVE: To evaluate whether this microcatheter first-pass effect can be used to differentiate ICAS from intracranial embolism. METHODS: A total of 61 patients with acute ischemic stroke resulting from large intracranial artery occlusion and in whom recanalization was achieved by endovascular treatment were included in the study. The microcatheter first-pass effect was tested in these patients. The sensitivity, specificity, positive predictive values (PPV), and accuracy of the microcatheter first-pass effect for prediction of ICAS were assessed. RESULTS: The microcatheter first-pass effect was more frequently observed in patients with ICAS than in those with intracranial embolism (90.9% vs 12.8%, P < .001). For identifying ICAS, sensitivity, specificity, PPV, and accuracy of the microcatheter first-pass effect were 90.9%, 87.2%, 80.0%, 88.5%, respectively. CONCLUSION: The sensitivity and PPV of the microcatheter first-pass effect are high for prediction of ICAS in patients with acute symptoms.
Assuntos
Arteriopatias Oclusivas/terapia , Isquemia Encefálica/terapia , Circulação Cerebrovascular/fisiologia , Arteriosclerose Intracraniana/terapia , Acidente Vascular Cerebral/terapia , Idoso , Arteriopatias Oclusivas/fisiopatologia , Isquemia Encefálica/fisiopatologia , Procedimentos Endovasculares , Feminino , Humanos , Arteriosclerose Intracraniana/fisiopatologia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Acidente Vascular Cerebral/fisiopatologiaRESUMO
BACKGROUND: Acute intracranial atherosclerotic disease (IAD)-related large artery occlusion (LAO) is typically refractory to mechanical thrombectomy. We evaluated the feasibility and safety of emergency balloon-assisted or stent-assisted angioplasty performed with tirofiban administration for acute IAD-related LAO. METHODS: We identified, from among 55 consecutive patients who underwent endovascular treatment for LAO, 12 patients with acute IAD-related LAO who underwent balloon-assisted or stent-assisted angioplasty with (n = 3) or without passage of a stent retriever. The treatment included tirofiban administration. We obtained, from patients' clinical records, thrombolysis in cerebral infarction scores (to assess the extent of reperfusion), follow-up magnetic resonance angiography images (to assess patency of the responsive arteries), and 90-day modified Rankin (mRS) scores (to assess outcomes). RESULTS: Temporary blood flow and severe stenosis were observed angiographically in all 12 patients, either when the stent retriever was deployed or when a microcatheter was advanced through the site of occlusion. Persistent recanalization was achieved in all patients, and there was no operative complication or arterial reocclusion. All 8 patients with an occluded major artery in the anterior circulation had a good outcome, with an mRS score of ≤2. Two of the 4 patients with basilar artery occlusion had a good outcome, with an mRS score of ≤2. One patient (25%) died within 72 hours after procedure. CONCLUSIONS: Our data point to the safety and feasibility of emergency balloon-assisted or stent-assisted angioplasty performed with tirofiban administration and a single or no passage of the stent retriever for acute IAD-related LAO.
Assuntos
Angioplastia com Balão , Estenose das Carótidas/terapia , Fibrinolíticos/uso terapêutico , Infarto da Artéria Cerebral Média/terapia , Arteriosclerose Intracraniana/terapia , Stents , Ativador de Plasminogênio Tecidual/uso terapêutico , Insuficiência Vertebrobasilar/terapia , Idoso , Angioplastia , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/terapia , Estenose das Carótidas/diagnóstico por imagem , Angiografia Cerebral , Emergências , Procedimentos Endovasculares , Estudos de Viabilidade , Feminino , Humanos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Arteriosclerose Intracraniana/diagnóstico por imagem , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Insuficiência Vertebrobasilar/diagnóstico por imagemRESUMO
BACKGROUND: Vertebral-basilar artery stenosis is associated with posterior circulation infarction. So correct detection of vertebral basilar artery stenosis is very important. Studies concerning the sensitivity and specificity of 3-dimensional contrast enhanced MR angiography (3D-CE-MRA) in detecting vertebral basilar artery stenosis is generally lacking. METHODS: Retrospectively reviewed the imagines of consecutive one hundred and forty-nine Chinese patients with ischemic stroke or vertigo/dizziness who underwent 3D-CE-MRA and DSA. DSA and CE-MRA images were studied separately and to determine the presence of mild, moderate, or severe stenosis of the vertebral-basilar arteries. Analysis combined with vascular origin image was applied when evaluating the vertebral artery origin stenosis. Sensitivity, specificity, positive and negative predictive values, and the accuracy of 3D-CE-MRA in detecting and grading of vertebral-basilar artery stenosis were calculated. RESULTS: Compared with DSA, sensitivity, specificity and accuracy of 3D-CE-MRA in detecting of vertebral artery origin ≥70% stenosis or occlusion was 97.1%, 77.4% and 81.9%, but diagnostic consistency was poor (K=0.59); Analysis combined with vascular origin images, the specificity (97.8%), accuracy (92.9%) and consistency (K=0.826) was significantly improved. CONCLUSIONS: 3D-CE-MRA is a sensitive and noninvasive technique for the detection of vertebral artery origin stenosis. Furthermore, analysis combined with vascular origin image would improve the diagnostic accuracy.
Assuntos
Angiografia Digital/normas , Meios de Contraste , Imageamento Tridimensional/normas , Angiografia por Ressonância Magnética/normas , Insuficiência Vertebrobasilar/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital/métodos , China/epidemiologia , Feminino , Humanos , Imageamento Tridimensional/métodos , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Insuficiência Vertebrobasilar/epidemiologiaRESUMO
The biochemical and enzymatic properties of four highly similar rice oxalate oxidase proteins (OsOxO1-4) were compared after their purification from the leaves of transgenic plants each overexpressing the respective OsOxO1-4 genes. Although alignment of their amino acid sequences has revealed divergence mainly in the signal peptides and they catalyze the same enzymic (oxalate oxidase) reaction, divergence in apparent molecular mass, Km, optimum pH, stability and responses to inhibitors and activators was uncovered by biochemical characterization of the purified OsOxO1-4 proteins. The apparent molecular mass of oligomer OsOxO1 was found to be similar to that of OsOxO3 but lower than the other two. The molecular mass of the subunit of OsOxO1 was lower than that of OsOxO3. The Km value of OsOxO3 was higher than the other three which had similar Km. OsOxO1 and OsOxO4 possessed peak activity at pH 8.5 which was close to that at the optimum pH 4.0. The activity of OsOxO2 at pH 8.5 was only 65% of that at its optimum pH 3.5, while the activity of OsOxO3 did not vary much at pH 6-9 and was also much lower than that at its optimum pH 3. OsOxO2 and OsOxO3 still maintained all their activities after being heated at 70°C for 1h while OsOxO1 and OsOxO4 lost about 30% of their activities. Pyruvate and oxaloacetic acid inhibited the activity of OsOxO3 more strongly than the other three. Interestingly, glucose 6-phosphate, fructose 6-phosphate and fructose 1,6-biphosphate related to photosynthetic assimilation of triose phosphate greatly increased the activities of OsOxO3 and OsOxO4. In addition to the differences in the biochemical properties of the four OsOxO proteins, an intriguing finding is that the purified OsOxO1-4 exhibited substrate inhibition, which is a typical of the classical Michaelis-Menten enzyme kinetics exhibited by a majority of other enzymes.
Assuntos
Oryza/enzimologia , Oryza/genética , Oxirredutases/genética , Sequência de Aminoácidos , Isoenzimas , Peso Molecular , Oxirredutases/metabolismo , Folhas de Planta/química , Plantas Geneticamente Modificadas/metabolismoRESUMO
Differential expression of rice oxalate oxidase genes (OsOxO1-4) in rice leaves (Oryza sativa L.) in response to biotic stress was assayed using RT-PCR. OsOxO4 was induced transiently at 12 h in plants inoculated with the pathogens of bacterial blight and that of the wounding control. Inoculation with the rice blast pathogen induced OsOxO2 expression compared to the mock spray control. Overexpressing OsOxO1 or OsOxO4 in rice resulted in elevated transcript levels of the respective transgene as well as OsOxO3 in leaves compared to that in untransformed wild type (WT). In a line of RNA-i transgenic rice plants (i-12), expression of all four OsOxO genes except that of OsOxO2 was severely inhibited. Oxalate oxidase (OxO, EC 1.2.3.4) activity in plants overexpressing OsOxO1 or OsOxO4 was substantially higher than that in WT and the RNA-i lines. It was found that transgenic rice plants with substantially higher OxO activity were not more resistant to rice blast and bacterial blight than WT. In contrast, some RNA-i lines with less OxO activity seemed to be more resistant to rice blast while some overexpressing lines were more susceptible to rice blast than WT. Therefore, OxO might not be a disease resistance factor in rice.
Assuntos
Resistência à Doença/genética , Oryza/genética , Oxirredutases/genética , Doenças das Plantas/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Regulação da Expressão Gênica de Plantas/genética , Folhas de Planta/genética , Transgenes/genéticaRESUMO
STUDY DESIGN: A prospective clinical trial was conducted. OBJECTIVE: To compare the clinical and radiologic late results of monosegmental transpedicular fixation versus short-segment pedicle instrumentation (SSPI) in management of thoracolumbar burst fractures and evaluate the efficacy of monosegmental transpedicular fixation. SUMMARY OF BACKGROUND DATA: SSPI (1 level above and 1 below the fracture level) are accepted by many surgeons as an accepted technique for the treatment of thoracolumbar burst fractures. To preserve more motion segments, some authors have advocated monosegmental pedicle instrumentation (MSPI). The recent developments showed that MSPI yielded good clinical results; however, there were no report about comparison of clinical outcome between monosegmental and biosegmental transpedicular fixation in management of thoracolumbar burst fractures. METHODS: Eighty-five patients with thoracolumbar burst fractures fulfilling the inclusion criteria were included in the study. The patients were randomized by a simple method into 2 groups. Group 1 were treated with monosegmental transpedicular fixation (n = 47), and group 2 were treated with biosegmental transpedicular fixation (n = 38). Clinical (Low Back Outcome Score and Oswestry Disability Index) and radiologic (load-sharing classification index, sagittal index, and percentage of anterior body height compression) outcomes were analyzed. RESULTS: The 2 groups were similar in age, follow-up period, and severity of the deformity and fracture. The postoperative and follow-up sagittal index, local kyphosis, percentage of anterior body height compression, and average correction loss in local kyphosis in both groups were not significantly different. The failure rate between the 2 surgical approaches was also not significantly different (group 1 = 6.38% and group 2 = 5.26%). Oswestry Disability Index improved in both groups by >25 points in a similar amount (P = 0.23). The average follow-up Low Back Outcome Score was 74.9 and 60.2 for group 1 and group 2, respectively (P = 0.033). CONCLUSION: In conclusion, radiologic parameters demonstrated that both MSPI and SSPI are the effective and reliable operative techniques for selected thoracolumbar burst fractures. MSPI shortened the operative time and decreased the amount of blood loss significantly and, thus, offered better clinical results. Nevertheless, long-term studies are supposed to be performed to support the outcomes.
Assuntos
Fixação Interna de Fraturas/métodos , Vértebras Lombares/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Vértebras Torácicas/cirurgia , Adulto , Parafusos Ósseos , Avaliação da Deficiência , Feminino , Fixação Interna de Fraturas/instrumentação , Humanos , Dor Lombar/diagnóstico , Dor Lombar/etiologia , Vértebras Lombares/lesões , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Vértebras Torácicas/lesões , Resultado do TratamentoRESUMO
OBJECTIVE: To investigate the molecular mechanism of TFE (total flavone of epimedium) in the treatment of osteoporosis, and then provide experimental evidence for modernization and further development of TFE as an traditional Chinese medicine. METHODS: Sixty healthy female SD rats with aged 4 months were randomly divided into three groups (including control group in which rats received sham surgery, OVX group in which ovariectomized rats didn't give any medicine after the removal of ovaries and TFE group in which ovariectomized rats administrated TFE), 20 rats in each group. Compared bone mineral density (BMD) between before operation and at 4th week after operation in order to verify the establishment of osteoporotic model (criteria: BMD decreased more than 20% at 4th week after operation). The rats in TEF group were administrated total flavone of epimedium(concentration 30 mg/ml, 10 ml/kg, qd) orally for 4 weeks. After this, killed rats to harvest the lower part of the femur and detected BMD again. Applying the reverse transcriptase-polymerase chain reaction technique (RT-PCR) to detect expression of OPG, OPGL mRNA in bone tissue. RESULTS: (1) At 4th week after ovariectomy, the mean BMD of lumbar vertebra in TFE group fell to (0.084 +/- 0.020) g/cm2. Administrated with TFE for 4 weeks,the BMD increased to (0.112 +/- 0.009) g/cm2. There was significant improvement compare with the OVX group (P < 0.05). (2) Compared between OVX group and TFE group, The OPG mRNA expression of TFE group obviously enhanced. There was significant difference in statistics (P < 0.05). However,the promotion for OPGL mRNA expression were detected between OVX group and TFE group,there was no significant difference in statistics (P > 0.05). CONCLUSION: This study showed that TFE could inhibit differentiation and maturation of osteoclast through enhancing OPG mRNA expression, accordingly,to treat osteoporosis.