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1.
Osteoporos Int ; 35(1): 143-152, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37674097

RESUMO

The Convolutional Neural Network algorithm achieved a sensitivity of 94% and specificity of 93% in identifying scans with vertebral fractures (VFs). The external validation results suggest that the algorithm provides an opportunity to aid radiologists with the early identification of VFs in routine CT scans of abdomen and chest. PURPOSE: To evaluate the performance of a previously trained Convolutional Neural Network (CNN) model to automatically detect vertebral fractures (VFs) in CT scans in an external validation cohort. METHODS: Two Chinese studies and clinical data were used to retrospectively select CT scans of the chest, abdomen and thoracolumbar spine in men and women aged ≥50 years. The CT scans were assessed using the semiquantitative (SQ) Genant classification for prevalent VFs in a process blinded to clinical information. The performance of the CNN model was evaluated against reference standard readings by the area under the receiver operating characteristics curve (AUROC), accuracy, Cohen's kappa, sensitivity, and specificity. RESULTS: A total of 4,810 subjects were included, with a median age of 62 years (IQR 56-67), of which 2,654 (55.2%) were females. The scans were acquired between January 2013 and January 2019 on 16 different CT scanners from three different manufacturers. 2,773 (57.7%) were abdominal CTs. A total of 628 scans (13.1%) had ≥1 VF (grade 2-3), representing 899 fractured vertebrae out of a total of 48,584 (1.9%) visualized vertebral bodies. The CNN's performance in identifying scans with ≥1 moderate or severe fractures achieved an AUROC of 0.94 (95% CI: 0.93-0.95), accuracy of 93% (95% CI: 93%-94%), kappa of 0.75 (95% CI: 0.72-0.77), a sensitivity of 94% (95% CI: 92-96%) and a specificity of 93% (95% CI: 93-94%). CONCLUSION: The algorithm demonstrated excellent performance in the identification of vertebral fractures in a cohort of chest and abdominal CT scans of Chinese patients ≥50 years.


Assuntos
Fraturas da Coluna Vertebral , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Redes Neurais de Computação
2.
Mol Cell Biochem ; 479(2): 313-323, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37067732

RESUMO

Indole-3-carboxaldehyde (I3A), one of tryptophan metabolites derived from gut microbiota, extends the lifespan of mice after high-dose ionizing radiation exposure. Persistent myelosuppression is the most common and fatal complication for victims of nuclear accidents and patients undergoing radiotherapy, with few therapeutic options available. However, whether and how I3A protects ionizing radiation-induced hematopoietic toxicity remain unknown. In this study, we demonstrated that I3A treatment effectively ameliorated radiation-induced hematopoietic injury through accelerating peripheral blood cells recovery, promoting bone marrow cellularity restoration and enhancing functional HSPC regeneration. Additionally, I3A also suppressed intracellular reactive oxygen species production and inhibited apoptosis in irradiated HSPCs. Mechanistically, I3A treatment significantly increased HSPC quiescence, thus conferring HSPCs with resistance against radiation injury. Finally, I3A treatment could improve survival of lethally irradiated mice. Taken together, our data suggest that I3A acts as a gut microbiota-derived paracrine factor that regulates HSPC regeneration and may serve as a promising therapeutic agent for ionizing radiation-induced myelosuppression.


Assuntos
Indóis , Células-Tronco , Humanos , Animais , Camundongos , Indóis/farmacologia , Células da Medula Óssea , Radiação Ionizante
3.
BMC Musculoskelet Disord ; 25(1): 478, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890605

RESUMO

BACKGROUND: The aim of the study was to investigate the muscle differences in children with osteogenesis imperfecta (OI) using opportunistic low-dose chest CT and to compare different methods for the segmentation of muscle in children. METHODS: This single center retrospective study enrolled children with OI and controls undergoing opportunistic low-dose chest CT obtained during the COVID pandemic. From the CT images, muscle size (cross-sectional area) and density (mean Hounsfield Units [HU]) of the trunk muscles were measured at the mid-T4 and the mid-T10 level using two methods, the fixed thresholds and the Gaussian mixture model. The Bland-Altman method was also used to compute the strength of agreement between two methods. Comparison of muscle results between OI and controls were analyzed with Student t tests. RESULTS: 20 children with OI (mean age, 9.1 ± 3.3 years, 15 males) and 40 age- and sex-matched controls were enrolled. Mean differences between two methods were good. Children with OI had lower T4 and T10 muscle density than controls measured by the fixed thresholds (41.2 HU vs. 48.0 HU, p < 0.01; 37.3 HU vs. 45.9 HU, p < 0.01). However, children with OI had lower T4 muscle size, T4 muscle density, T10 muscle size and T10 muscle density than controls measured by the Gaussian mixture model (110.9 vs. 127.2 cm2, p = 0.03; 44.6 HU vs. 51.3 HU, p < 0.01; 72.6 vs. 88.0 cm2, p = 0.01; 41.6 HU vs. 50.3 HU, p < 0.01, respectively). CONCLUSIONS: Children with OI had lower trunk muscle density indicating that OI might also impair muscle quality. Moreover, the fixed thresholds may not be suitable for segmentation of muscle in children.


Assuntos
Músculo Esquelético , Osteogênese Imperfeita , Tomografia Computadorizada por Raios X , Humanos , Osteogênese Imperfeita/diagnóstico por imagem , Masculino , Feminino , Criança , Estudos Retrospectivos , Estudos de Casos e Controles , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia , Adolescente , COVID-19/diagnóstico por imagem , Doses de Radiação , Pré-Escolar
4.
Skeletal Radiol ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695874

RESUMO

OBJECTIVE: To determine which bones and which grades had the highest inter-rater variability when employing the Tanner-Whitehouse (T-W) method. MATERIALS AND METHODS: Twenty-four radiologists were recruited and trained in the T-W classification of skeletal development. The consistency and skill of the radiologists in determining bone development status were assessed using 20 pediatric hand radiographs of children aged 1 to 18 years old. Four radiologists had a poor concordance rate and were excluded. The remaining 20 radiologists undertook a repeat reading of the radiographs, and their results were analyzed by comparing them with the mean assessment of two senior experts as the reference standard. Concordance rate, scoring, and Kendall's W were calculated to evaluate accuracy and consistency. RESULTS: Both the radius, ulna, and short finger (RUS) system (Kendall's W = 0.833) and the carpal (C) system (Kendall's W = 0.944) had excellent consistency, with the RUS system outperforming the C system in terms of scores. The repeatability analysis showed that the second rating test, performed after 2 months of further bone age assessment (BAA) practice, was more consistent and accurate than the first. The capitate had the lowest average concordance rate and scoring, as well as the lowest overall concordance rate for its D classification. Moreover, the G classifications of the seven carpal bones all had a concordance rate less than 0.6. The bones with lower Kendall's W were likewise those with lower scores and concordance rates. CONCLUSION: The D grade of the capitate showed the highest variation, and the use of the Tanner-Whitehouse 3rd edition (T-W3) to determine bone age (BA) was frequently inconsistent. A more comprehensive description with a focus on inaccuracy bones or ratings and a modification to the T-W3 approach would significantly advance BAA.

5.
Eur Radiol ; 33(1): 578-586, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35932305

RESUMO

OBJECTIVES: Organ fat may affect bone metabolism and be associated with vertebral fracture (VF). This study aimed to explore relationships between VF, adiposity indexes measured by MRI, and volumetric BMD (vBMD) measured by quantitative CT (QCT). METHODS: Four hundred volunteers, ranging in age from 22 to 83 years, were recruited and underwent same-day abdominal QCT and chemical shift-encoded (CSE) MRI. We used MRI to quantify the fat content of bone marrow (BMF), psoas major and paraspinal muscles, and the liver. Abdominal fat, VF, and vBMD of the lumbar spine were measured by QCT. For VF discrimination analysis, we examined both the whole cohort (60 VF cases in 30 men and 30 women) and a restricted subgroup of those aged over 50 years (50 VF cases in 23 men and 27 women). RESULTS: Amongst the men, a 1 SD increase in BMF was associated with a 27.67 (95% CI, -32.71 to -22.62) mg/cm3 decrease in vBMD after adjusting for age and BMI. Amongst women, all adiposity indexes except for liver fat were significantly associated with vBMD, with BMF having the strongest association (ß, -24.00; 95% CI, -28.54 to -19.46 mg/cm3). Similar findings were also observed in participants aged over 50 years. The associations of adiposity indexes with vertebral fracture were not significant after adjusting for age in both sexes aged over 50 years. CONCLUSIONS: In both sexes, higher bone marrow fat was associated with lower vBMD at the spine. However, marrow fat and other adipose tissues were not associated with radiographic-based prevalent vertebral fractures. KEY POINTS: • In both sexes, higher bone marrow fat was associated with lower vBMD at the spine. • Among women, all adiposity indexes except for liver fat content were significantly associated with vBMD, with bone marrow fat having the strongest association. • Marrow fat and other adipose tissues were not associated with radiographic-based asymptomatic vertebral fractures.


Assuntos
Fraturas da Coluna Vertebral , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Adulto , Idoso , Idoso de 80 Anos ou mais , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/metabolismo , Medula Óssea/diagnóstico por imagem , Medula Óssea/metabolismo , Densidade Óssea/fisiologia , Tomografia Computadorizada por Raios X , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/metabolismo
6.
J Bone Miner Metab ; 41(4): 522-532, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36949139

RESUMO

INTRODUCTION: Lumbar intervertebral disc degeneration (LDD) and osteoporosis (OP) are age-related conditions that induce low back pain and have an impact on quality of life. The relationship between LDD and changes in bone mineral density (BMD) is, however, contentious and ever-changing. The purpose of this study is to investigate the relationship between lumbar vertebral volumetric BMD (vBMD) and LDD in an urban population of young and middle-aged community-dwelling Chinese adults. MATERIALS AND METHODS: 719 participants were recruited from among the subjects enrolled in a 10-year longitudinal study of degeneration of the spine and knee being conducted at the Beijing Jishuitan Hospital. The severity of LDD was graded using the five-grade Pfirrmann classification, and lumbar vertebral vBMD was measured using quantitative computed tomography (QCT). The relationship between the grade of intervertebral disc degeneration and lumbar vertebral vBMD was analyzed, and multiple linear regression was performed to adjust for covariates. RESULTS: The mean lumbar vBMD decreased as the grade of LDD increased (171.5 g/cm3, 147.8 g/cm3, and 124.3 g/cm3, respectively; P < 0.001). After adjusting for age, a higher LDD stage was associated with a lower mean L2-L4 vBMD, although a statistically significant correlation was observed only in men (standardized coefficient ß = - 0.656, P = 0.004). In men, there was a negative correlation between single-vertebra vBMD and degeneration of adjacent intervertebral discs, particularly those involving the L3 vertebra (L2-3 disc: ß = - 0.333, P < 0.001, L3-4 disc: ß = - 0.398, P < 0.001), as well as the mean grade of the L2-4 discs (ß = - 0.448, P < 0.001). However, the L5-S1 disc had a smaller correlation with age than others, and no statistically significant associations with lumbar vBMD were observed in either men (ß = - 0.024, P = 0.729) or women (ß = - 0.057, P = 0.396). CONCLUSION: Our study found that the degree of LDD was negatively associated with lumbar trabecular vBMD, although (excepting the L5-S1 disc), the relationship was statistically significant only in men.


Assuntos
Degeneração do Disco Intervertebral , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Densidade Óssea , Estudos Transversais , População do Leste Asiático , Vida Independente , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/epidemiologia , Estudos Longitudinais , Vértebras Lombares/diagnóstico por imagem , Qualidade de Vida , População Urbana , Tomografia Computadorizada por Raios X
7.
Acta Radiol ; 64(6): 2152-2161, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37151038

RESUMO

BACKGROUND: Computed tomography (CT) is the gold standard for analyzing muscle parameters. PURPOSE: To clarify sex-specific paraspinal muscle area (PMA), paraspinal muscle index (PMI), and muscle fat infiltration (MFI) percentiles. MATERIAL AND METHODS: This was a cross-sectional study of 760 individuals (45% men; age range = 20-92 years; mean age = 53.4 ± 21.1 years) with a body mass index (BMI) in the range of 16.4-38.1 kg/m2. CT scans were retrospectively used to establish PMA, PMI, and MFI at L3 level using a deep-learning (DL) tool. Sex-specific distributions for these parameters were assessed based on associations between age/BMI and individual muscle parameters, after which age- and BMI-specific percentile estimates were determined. The 5th percentile was regarded as the cutoff for PMA/PMI, and the 95th percentile was regarded as the cutoff for MFI. RESULTS: Sex-specific PMA, PMI, and MFI cutoffs in the paraspinal muscles group were 52.9 cm2, 15.0 cm2/m2, and 33.3%, respectively, in men, and 33.2 cm2, 9.5 cm2/m2, and 41.2% in women. Age was moderately negatively correlated with PMA and was strongly negatively correlated with PMI, but age was strongly positively correlated with MFI. BMI was moderately positively correlated with PMA/PMI in men and strongly positively correlated in women; BMI was weakly positively correlated with MFI, thus enabling the establishment of age- and BMI-specific cutoff percentiles. CONCLUSION: Sex-specific PMA, PMI, and MFI percentiles and age- and BMI-specific cutoff values for these parameters were successfully established for an outpatient population.


Assuntos
Vértebras Lombares , Músculos Paraespinais , Masculino , Humanos , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Músculos Paraespinais/diagnóstico por imagem , Estudos Transversais , Estudos Retrospectivos , Vértebras Lombares/diagnóstico por imagem , Tomografia Computadorizada por Raios X
8.
BMC Musculoskelet Disord ; 24(1): 258, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37013527

RESUMO

BACKGROUND: Lumbar vertebral endplates lesions (LEPLs), one of the etiologies of low back pain (LBP), are one of the most prevalent causes of health-care costs. Despite progressively becoming the focus in recent years, almost all studies have concentrated on symptomatic patients rather than general populations. As a result, our study was designed to determine the prevalence and distribution patterns of LEPLs in a middle-young general population, as well as their associations with lumbar disc herniation (LDH), lumbar disc degeneration (LDD), and lumbar vertebral volumetric bone mineral density (vBMD). METHODS: Seven hundred fifty-four participants aged 20-60 years were recruited from the subjects enrolled in a 10-year longitudinal study of degeneration of the spine and knee being conducted at the Beijing Jishuitan Hospital and 4 of them were excluded due to the missing of MRIs. In this observational study, a lumbar quantitative computed tomography (QCT) and MRI scan were performed among participants within 48 h. T2-weighted sagittal lumbar MRI images for all included subjects were identified for LEPLs by two independent observers based on morphological and local characteristics. Lumbar vertebral vBMD was measured with QCT. The age, BMI, waistline, hipline, lumbar vBMD, LDD, and LDH were measured to investigate their associations with LEPLs. RESULTS: The prevalence of LEPLs was higher among the male subjects. 80% of endplates were recognition as no lesions with a substantial disparity between female (75.6%) and male subjects (83.4%) (p < 0.001). The most common lesions were "wavy/irregular" and "notched", and "fracture" is most involved in L3-4 inferior endplate both in two genders. LEPLs were found to be associated with LDH (≥ 2 levels: OR = 6.859, P < 0.001; 1 level: OR = 2.328, P = 0.002 in men. OR = 5.004, P < 0.001; OR = 1.805, P = 0.014 in women) reference for non-LDH, and hipline in men (OR = 1.123, P < 0.001). CONCLUSIONS: LEPLs are the common findings on lumbar MRIs in general population, particularly in men. The presence of these lesions and advance from slightly to severely could be mainly attributed to LDH and men's higher hipline.


Assuntos
Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Feminino , Humanos , Masculino , Densidade Óssea , População do Leste Asiático , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/epidemiologia , Degeneração do Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/epidemiologia , Deslocamento do Disco Intervertebral/patologia , Estudos Longitudinais , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética/métodos , Adulto Jovem , Adulto , Pessoa de Meia-Idade
9.
BMC Musculoskelet Disord ; 23(1): 11, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34980055

RESUMO

BACKGROUND: The plantar plate is an important static stabilizer of the lesser metatarsophalangeal joints, and disruptions of the plantar plate can lead to significant instability and lesser toe deformities. In recent years, direct plantar plate repair has been proposed. Although direct repair via a dorsal approach is attractive, a torn plantar plate is small and difficult to access using regular instruments in a restricted operative field. METHODS: In this report, a unique method for plantar plate repairs was used to repair various configurations of plantar plate tears with standard operative instruments that are available in most operating rooms. RESULTS: Using this method, 10 patients underwent plantar plate repairs, and the mean follow-up period was 24 (range, 14-38) months. The mean visual analog scale score for pain preoperatively was 4.1 (range, 0-6) and decreased to 0.6 (range, 0-3) at last follow-up. Postoperatively, the mean visual analog scale score for satisfaction was 9.6 (range, 8-10) and the mean American Orthopedic Foot and Ankle Society forefoot score was 88.8 (range, 75-100). CONCLUSIONS: Our study proposes an inexpensive and versatile method for plantar plate repair via a dorsal approach that uses standard operative instruments. TRIAL REGISTRATION: ClinicalTrials.gov , NCT04949685 . July 2, 2021 - Retrospectively registered, LEVEL OF CLINICAL EVIDENCE: 4.


Assuntos
Deformidades do Pé , Instabilidade Articular , Articulação Metatarsofalângica , Placa Plantar , Humanos , Osteotomia , Placa Plantar/cirurgia
10.
Medicina (Kaunas) ; 58(3)2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35334621

RESUMO

BACKGROUND AND OBJECTIVES: In patients with ankle fractures complicated by syndesmotic injuries, no consensus has been reached on the best method of syndesmosis fixation using syndesmotic screws. One previous study revealed no difference in the tibiofibular overlap between two groups with or without syndesmotic screw removal. Other studies have indicated that distal tibiofibular diastasis exists after the removal of syndesmotic screws. In this study, we aimed to confirm the effect of syndesmotic screw removal on diastasis occurrence. We further analyzed the risk factors that may contribute to the widening of the tibiofibular syndesmosis. MATERIALS AND METHODS: This retrospective study involved a review of the records of 63 patients with ankle fractures accompanied by syndesmosis injuries that required syndesmotic screw fixation. Anteroposterior radiographs were analyzed for each patient at various time points, from syndesmotic screw fixation to outpatient department follow-ups after screw removal. The changes in tibia-fibula overlap (OL), tibia-fibula clear space (CS), and medial clear space (MCS) were analyzed. Further analysis was performed to reveal potential factors that may have contributed to radiographic differences. RESULTS: Compared with the postoperation radiographs following syndesmotic screw fixation, OL decreased (2.0 mm) and CS increased (0.8 mm) in the anteroposterior radiographs from outpatient department follow-ups. No significant changes were noted in OL or CS after syndesmotic screw removal. However, OL decreased (1.8 mm) and CS increased (0.5 mm) before syndesmotic screw removal. No significant change in MCS occurred during the whole observation period. Linear regression analysis did not reveal any significant correlations between potentially related factors and radiographic changes. CONCLUSIONS: Marked diastasis had occurred at final follow-up. Notably, the diastasis occurred before rather than after screw removal. This implies that screw removal does not significantly influence the radiographic outcomes of rotational ankle fractures.


Assuntos
Traumatismos do Tornozelo , Parafusos Ósseos , Traumatismos do Tornozelo/diagnóstico por imagem , Traumatismos do Tornozelo/cirurgia , Articulação do Tornozelo , Fixação Interna de Fraturas , Humanos , Estudos Retrospectivos
11.
Metab Eng ; 68: 187-198, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34673237

RESUMO

Herbicide-resistance in weeds has become a serious threat to agriculture across the world. Thus, there is an urgent need for the discovery and development of herbicides with new modes of action. Thaxtomin phytotoxins are a group of nitrated diketopiperazines produced by potato common scab-causing phytopathogen Streptomyces scabies and other actinobacterial pathogens. They are generally considered to function as inhibitors of cellulose synthesis in plants, and thus have great potential to be used as natural herbicides. Generation of an overproducing strain is crucial for the scale-up production of thaxtomins and their wide use in agriculture. In the present study, we employed a stepwise strategy by combining heterologous expression, repressor deletion, activator overexpression, and optimization of fermentation media for high-level production of thaxtomins. The maximum yield of 728 mg/L thaxtomins was achieved with engineered Streptomyces albidoflavus J1074 strains in shake-flask cultures, and it was approximately 36-fold higher than S. albidoflavus J1074 carrying the unmodified cluster. Moreover, the yield of thaxtomins could reach 1973 mg/L when the engineered strain was cultivated in a small-scale stirred-tank bioreactor. This is the highest titer reported to date, representing a significant leap forward for the scale-up production of thaxtomins. Our study presents a robust, easy-to-use system that will be broadly useful for improving titers of bioactive compounds in many Streptomyces species.


Assuntos
Engenharia Metabólica , Streptomyces , Indóis , Piperazinas , Streptomyces/genética
12.
Int J Mol Sci ; 22(10)2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-34063380

RESUMO

MicroRNAs (miRNAs) could serve as ideal entry points to the deregulated pathways in osteoporosis due to their relatively simple upstream and downstream relationships with other molecules in the signaling cascades. Our study aimed to give a comprehensive review of the already identified miRNAs in osteoporosis from human blood samples and provide useful information for their clinical application. A systematic literature search for relevant studies was conducted in the Pubmed database from inception to December 2020. We set two essential inclusion criteria: human blood sampling and design of controlled studies. We sorted the results of analysis on human blood samples according to the study settings and compiled the most promising miRNAs with analyzed diagnostic values. Furthermore, in vitro and in vivo evidence for the mechanisms of the identified miRNAs was also illustrated. Based on both diagnostic value and evidence of mechanism from in vitro and in vivo experiments, miR-23b-3p, miR-140-3p, miR-300, miR-155-5p, miR-208a-3p, and miR-637 were preferred candidates in diagnostic panels and as therapeutic agents. Further studies are needed to build sound foundations for the clinical usage of miRNAs in osteoporosis.


Assuntos
MicroRNAs/sangue , MicroRNAs/genética , Osteoporose/genética , Fraturas por Osteoporose/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estrogênios/sangue , Feminino , Idoso Fragilizado , Humanos , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Osteoporose/complicações , Osteoporose/metabolismo , Via de Sinalização Wnt/genética
13.
Crit Rev Biotechnol ; 40(8): 1163-1171, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32819175

RESUMO

Herbicide-resistant weeds are a growing problem worldwide. Thaxtomin phytotoxins are a group of nitrated diketopiperazines produced by the potato common scab-causing pathogen Streptomyces scabies and other actinobacterial plant pathogens. They represent a unique class of microbial natural products with distinctive structural features and promising herbicidal activity. The biosynthesis of thaxtomins proceeds through multiple steps of unusual enzymatic reactions. Advances in understanding of thaxtomins biosynthetic machinery have provided the basis for precursor-directed biosynthesis, pathway refactoring, and one-pot biocombinatorial synthesis to generate thaxtomin analogues. We herein summarize recent findings on the biosynthesis of thaxtomins and highlight recent advances in the rational generation of novel thaxtomins for the development of potent herbicidal agents.


Assuntos
Vias Biossintéticas , Herbicidas/metabolismo , Engenharia Metabólica , Plantas Daninhas , Solanum tuberosum/microbiologia , Streptomyces
14.
Pain Med ; 21(4): 822-835, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31626282

RESUMO

OBJECTIVE: The objective of this study was to assess the efficacy and safety of extracorporeal shockwave therapy (ESWT) for treatment of knee osteoarthritis (OA) using a systemic review and meta-analysis. METHODS: An extensive search of relevant articles from electronic databases Pubmed, Embase, and Cochrane Library from inception to March 2019 was conducted. The treatment outcomes (visual analog scale [VAS] and the Western Ontario and McMaster Universities Arthritis Index [WOMAC]) of the included articles were pooled to calculate effect sizes. The assessment of heterogeneity among articles was evaluated using I2. Statistical analyses were conducted using RevMan software. RESULTS: The results showed that the ESWT group had significant improvement in pain relief compared with the control group through 12 months based on WOMAC and VAS scores. Compared with the baseline level, the patients had significant improvement in pain relief at most follow-up points (one week to 12 months) based on WOMAC and VAS scores. The patients showed significant improvement in physical function at six- and 12-month follow-up when compared with the control group and for all follow-up (one to 12 months) when compared with the baseline level. Additionally, only minor complications were observed after ESWT treatment. CONCLUSIONS: The use of ESWT for treatment of knee OA had a beneficial effect on pain relief and physical function improvement for up to 12 months, and only minor complications occurred after ESWT treatment. However, there remains a lack of clarity regarding the frequency and dosage levels of ESWT required to achieve the maximum improvement.


Assuntos
Tratamento por Ondas de Choque Extracorpóreas/métodos , Osteoartrite do Joelho/terapia , Humanos , Osteoartrite do Joelho/fisiopatologia , Resultado do Tratamento
15.
Clin Rehabil ; 34(9): 1217-1229, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32539454

RESUMO

OBJECTIVE: To compare the efficacy of various strategies in the treatment of trigger finger. DATA SOURCES: A systematic literature search for randomized controlled trials to compare treatments for trigger finger was conducted through three online databases, Pubmed, Embase and Cochrane Library, from their inception dates to 22 May 2020. METHODS: Relative risk (RR) with 95% confidence interval (CI) was used to evaluate the effect sizes in success rate for included articles. RESULTS: Sixteen articles (n = 1185) were included in our meta-analysis. The results showed that the efficacy of steroid injection was significantly better than the placebo group at short-term follow-ups (RR = 19.00, 95% CI = 1.17-309.77 for one-week; RR = 3.70, 95% CI = 3.70, 95% CI = 1.61-8.53 for one-month), and then became non-significant at four months (RR = 3.21, 95% CI = 0.88-11.79). There was no significant difference in success rate between steroid injection and nonsteroidal anti-inflammatory drug injection, and between open surgery and percutaneous release at all the follow-ups. Only surgical treatment had significantly better efficacy in success rate than steroid injection at all follow-ups (RR = 0.48, 95% CI = 0.34-0.66 for one-month; RR = 0.87, 95% CI = 0.80-0.96 for three-month; RR = 0.58, 95% CI = 0.48-0.68 for six-month; RR = 0.38, 95% CI = 0.20-0.72 for 12-month). CONCLUSION: There were no differences in efficacy between steroid injection and shockwave or nonsteroidal anti-inflammatory drug injection. The surgical treatments had the best efficacy among these treatments.


Assuntos
Dedo em Gatilho/terapia , Humanos
16.
J Foot Ankle Surg ; 59(5): 1032-1039, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32709528

RESUMO

Ankle arthrodesis (AA) and total ankle arthroplasty (TAA) are the 2 primary surgical treatments for patients with end-stage ankle arthritis. The comparative outcomes between AA and TAA using modern techniques remain unclear. A systematic search to identify all relevant articles comparing AA with TAA was conducted through 3 online databases. The clinical outcomes were extracted for meta-analysis, including AOFAS (American Orthopaedic Foot & Ankle Society) score, VAS (visual analog scale), AOS (Ankle Osteoarthritis Scale), gait analysis, ROM (range of motion), satisfaction, complication, and reoperation. Our meta-analysis shows no heterogeneity in any subgroup analyses. There were no significant differences in AOFAS total, pain, and alignment scores between the AA and TAA groups. The TAA group had significant improvement in AOFAS function score compared with the AA group. There was no significant difference in VAS and AOS total scores between the 2 groups. No significant differences in gait analysis were observed between the 2 groups. The TAA group had significant improvement in both ROM and change in ROM compared with the AA group. There was no significant difference in satisfaction rate between the 2 groups. The TAA group had significantly higher complication and reoperation rates compared with the AA group. Our meta-analysis provides updated evidence on clinical outcomes comparing AA with TAA using third-generation implants. The TAA group had better improvement in AOFAS function and ROM than the AA group. No significant differences in pain relief, gait analysis, or patient satisfaction were observed between the 2 groups.


Assuntos
Tornozelo , Artroplastia de Substituição do Tornozelo , Articulação do Tornozelo/cirurgia , Artrodese , Artroplastia de Substituição do Tornozelo/efeitos adversos , Humanos , Estudos Retrospectivos , Resultado do Tratamento
17.
Molecules ; 24(1)2019 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-30609798

RESUMO

Osteoporosis is the second most common epidemiologic disease in the aging population worldwide. Previous studies have found that frequent tea drinkers have higher bone mineral density and less hip fracture. We previously found that (-)-epigallocatechin gallate (EGCG) (20⁻100 µmol/L) significantly suppressed receptor activator of nuclear factor-kB ligand (RANKL)-induced osteoclastogenesis and pit formation via inhibiting NF-κB transcriptional activity and nuclear transport of NF-κB in RAW 264.7 cells and murine primary bone marrow macrophage cells. The most important regulation in osteoclastogenesis is the receptor activator of nuclear factor-kB/RANKL/osteoprotegrin (RANK/RANKL/OPG) pathway. In this study, we used the coculture of RAW 264.7 cells and the feeder cells, ST2, to evaluate how EGCG regulated the RANK/RANKL/OPG pathway in RAW 264.7 cells and ST2 cells. We found EGCG decreased the RANKL/OPG ratio in both mRNA expression and secretory protein levels and eventually decreased osteoclastogenesis by TRAP (+) stain osteoclasts and TRAP activity at low concentrations-1 and 10 µmol/L-via the RANK/RANKL/OPG pathway. The effective concentration can be easily achieved in daily tea consumption. Taken together, our results implicate that EGCG could be an important nutrient in modulating bone resorption.


Assuntos
Catequina/análogos & derivados , Osteogênese/efeitos dos fármacos , Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Animais , Catequina/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Expressão Gênica , Camundongos , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteogênese/genética , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fosfatase Ácida Resistente a Tartarato/metabolismo
18.
J Arthroplasty ; 30(5): 776-80, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25534864

RESUMO

The purpose of this study is to investigate the effect of preoperative intravenous (IV) and intraoperative topical administration of tranexamic acid (TXA) in total knee arthroplasty (TKA). A total of 120 patients were and randomly allocated to either topical group, combined group, or control group. The mean total blood loss was lower in the combined and topical groups (705 mL and 579 mL, respectively) in comparison with control group (949 mL, P < 0.001). There was a significant difference in transfusion rate among groups (P = 0.009). The postoperative hemoglobin drop and total drain amount were significantly less in the combined group compared to other groups. In conclusion, combining preoperative IV injection and topical administration of TXA can effectively reduce blood loss and transfusion rate.


Assuntos
Antifibrinolíticos/administração & dosagem , Artroplastia do Joelho , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Sangue , Hemorragia Pós-Operatória/prevenção & controle , Ácido Tranexâmico/administração & dosagem , Administração Intravenosa , Administração Tópica , Idoso , Idoso de 80 Anos ou mais , Drenagem , Feminino , Humanos , Injeções Intra-Articulares , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos
20.
Br J Radiol ; 97(1157): 1003-1009, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38457607

RESUMO

OBJECTIVES: To compare the performance of areal Hounsfield units (aHUs), volumetric Hounsfield units (vHUs), and volumetric bone mineral density (vBMD) by quantitative CT (QCT) in discriminating vertebral fractures (VFs) risk. METHODS: We retrospectively included CT scans of the lumbar spine 101 VFs cases (60 women, mean age: 64 ± 4 years; 41 men, mean age: 73 ± 10 years) and sex- and age-matched 101 control subjects (60 women, mean age: 64 ± 4 years; 41 men, mean age: 72 ± 7 years). In order to assess the discriminatory capability of aHU, vHU, and vBMD measurements at the L1 and L2 levels in identifying VFs, we conducted binary logistic regression and receiver operating characteristic (ROC) curve analyses in men and women. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. RESULTS: In both men and women with and without VFs, aHU, vHU, and vBMD were highly correlated with each other (r2 from 0.832 to 0.957, all P < .001). There was a statistically significant difference in aHU, vHU, and vBMD between subjects with and without VFs (P < .001). When age, gender, and BMI were taken into account as covariances and adjusted simultaneously, odds ratios (ORs) for aHU, vHU, and vBMD values, which represent the risk of VFs, were significant (P < .001). Compared with aHU and vHU, vBMD was more strongly associated with VF risk (vBMD: OR, 6.29; 95% CI, 3.83-10.35 vs vHU: OR, 3.64; 95% CI, 2.43-5.46 vs aHU: OR, 2.56; 95% CI, 1.79-3.67). In both men and women, further, vBMD had higher values for AUC, sensitivity, specificity, PPV, and NPV compared to vHU, with vHU in turn surpassing aHU. The area under the receiver operating characteristic curve (AUC) for discriminating VFs using the average aHU, vHU, and vBMD of 2 vertebrae was 0.72, 0.77, and 0.87 in men and 0.76, 0.79, and 0.86 in women. In both men and women, there exist statistically significant differences in the AUC when employing the 3 measurements-namely, aHU, vHU, and vBMD-to discriminate fractures (P < .05). CONCLUSIONS: The QCT-measured vBMD is more associated with acute VFs than vHU and aHU values of the lumbar spine. Although the use of vHU and aHU values for the diagnosis of osteoporosis and discriminating fracture risk is limited to scanner- and imaging protocol-specific, they have great potential for opportunistic osteoporosis screening, particularly vHU. ADVANCES IN KNOWLEDGE: The novelty of this study presents a comparison of the VF discriminative capabilities among aHU, vHU, and vBMD. The vHU values introduced in this study demonstrate a greater capacity to discriminate fractures compared to aHU, presenting an improved clinical choice. Although its discriminatory capability is slightly lower than that of vBMD, it is more convenient to measure and does not require specialized software.


Assuntos
Densidade Óssea , Vértebras Lombares , Fraturas da Coluna Vertebral , Tomografia Computadorizada por Raios X , Humanos , Feminino , Masculino , Idoso , Fraturas da Coluna Vertebral/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Sensibilidade e Especificidade , Curva ROC , Estudos de Casos e Controles
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