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Integrated power dividers (PDs) are essential in terahertz (THz) communication and radar systems, but miniaturization often leads to performance degradation due to fabrication inaccuracies and sharp bends. Topological photonics offers a solution to these issues, yet creating THz power dividers with arbitrary splitting ratios remains challenging. We present a design methodology for on-chip topological THz power dividers with customizable splitting ratios using valley-locked photonic crystals. These crystals feature a tri-layered structure with two distinct valley Chern number layers and an intermediate semimetal layer. Utilizing the Jackiw-Rebbi model, we show that the characteristic impedance of the valley-locked photonic crystals, and thus the power division ratio, can be tuned by adjusting the semimetal layer width. Our approach is validated through simulations and experiments for both equal (1:1) and unequal (4:9) power ratios. This method enables efficient navigation around sharp bends and robust THz on-chip connectivity.
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Satellite-based formaldehydeï¼HCHOï¼columns and tropospheric nitrogen dioxide columns were observed using the Ozone Monitoring Instrumentï¼OMIï¼ï¼and groundbased observations of ozoneï¼O3ï¼for May-August from 2013 to 2022 were connected to calculate the threshold values of the HCHO to NO2 ratioï¼FNRï¼in Shanxi Province. Thenï¼the spatiotemporal distributions and variations in summertime ozone photochemical production regimes were analyzed. The results showed thatï¼â The volatile organic compoundï¼VOCï¼ -sensitive regime areaï¼FNR < 2.3ï¼was obviously reducedï¼while the VOCs-NOx transitional regimeï¼FNR between 2.3-4.1ï¼area increased in the early years and then decreasedï¼ and NO x -sensitive regime area expanded significantly in summer from 2013 to 2022 over Shanxi Province. â¡ The increased summertime FNR during 2013 to 2019 was associated with the co-effect of increased HCHO columns and decreased tropospheric NO2 columns. The Shanxi Province was generally under an NOx regime since 2016ï¼which reflected the remarkable effect of NO x emission reductionsï¼howeverï¼there was a shift from a VOC-sensitive regime to a VOCs-NOx transitional regimeï¼in which O3 pollution aggravation was widespread under the background of decreased NOx emissions. The decrease in O3 concentration during 2020 to 2022 followed the synergistical declines in HCHO columns and tropospheric NO2 columns. ⢠The O3 weekend effects were reversed in Linfen and Yuncheng but were persistent in the other nine cities. Satellite-based weekend HCHO and NO2 levels were higher than those on weekdays in some cities of Shanxi Provinceï¼indicating that the O3 weekend effect was not only dependent on the changes of precursors emissions but was also closely related to O3 photochemical production sensitivity. The results indicated the necessity of simultaneous controls in NOx emissions and VOCs emissions for ozone abatement plans over Shanxi Province. In additionï¼Taiyuanï¼Yangquanï¼Yunchengï¼and Jincheng should continue to promote reduction in NOx emissions.
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BACKGROUND: Neuromyelitis optica spectrum disorder (NMOSD) is a group of inflammatory diseases affecting the central nervous system, characterized by optic neuritis and myelitis. The complex nature of NMOSD and varied patient response necessitates personalized treatment and efficient patient stratification strategies. OBJECTIVE: To provide a comprehensive review of recent advances in clinical and biomarker research related to aquaporin-4 (AQP4)-immunoglobulin G (IgG)-seropositive NMOSD prognosis and identify key areas for future research. METHODS: A comprehensive review and synthesis of recent literature were conducted, focusing on demographic factors and laboratory investigations. RESULTS: Demographic factors, such as age, ethnicity, and sex, influence NMOSD prognosis. Key biomarkers for NMOSD prognosis include homocysteine, antinuclear antibodies, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, thyroid hormone levels, neurofilament light chain levels, and serum glial fibrillary acidic protein might also predict NMOSD attack prognosis. CONCLUSION: Further investigation is required to understand sex-related disparities and biomarker inconsistencies. Identification and understanding of these factors can aid in the development of personalized therapeutic strategies, thereby improving outcomes for NMOSD patients. Future studies should focus on unifying research design for consistent results.
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Neuromielitis Óptica , Humanos , Inmunoglobulina G , Pronóstico , Acuaporina 4 , Biomarcadores , Autoanticuerpos , DemografíaRESUMEN
According to the systematic review of text and opinion(SrTO) developed by the Joanna Briggs Institute(JBI), this study integrated the evidence of the medical cases, papers, medical experience, and other related research of famous experts and schools on the treatment of chronic renal failure in the field of traditional Chinese medicine(TCM) nephropathy, analyzed the academic characteristics and influencing factors from the aspects of the principle, method, recipe, and medicines, and explored the internal logic and law of inheritance and innovation in TCM nephropathy. A total of 36 famous TCM experts and 4 schools were included. The work areas are concentrated in North and South China. 94.0% of the famous TCM experts have experienced master-disciple teaching. 27.8% have studied TCM through family succession. 38.9% have been taught by multiple famous teachers. And 5.6% have not experienced master-disciple teaching. In terms of principle, method, recipe, and medicines, many innovations have been made, with 30.6% of famous TCM experts proposing new theories, 11.1% advocating staged treatment of chronic renal failure, and 47.2% summarizing the treatment methods. The formation of the academic thoughts of contemporary famous TCM experts and schools on the treatment of chronic renal failure is closely related to the learning mode, era, and work area. Contemporary famous TCM experts and schools have the academic characteristics of combining classical and clinical theories and paying more attention to TCM with western medicine supplemented. The field of TCM nephropathy has the characteristics of simultaneous inheritance and innovation. On the basis of inheriting the classical theories of TCM, it absorbs modern medical theories, combines clinical diagnosis with the syndrome and treatment law of contemporary diseases, and makes innovations in principle, method, recipe, and medicines, which has significant clinical efficacy in the treatment of chronic renal failure.
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Medicamentos Herbarios Chinos , Fallo Renal Crónico , Humanos , Medicina Tradicional China , Instituciones Académicas , China , Fallo Renal Crónico/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéuticoRESUMEN
This study systematically searched and sorted out randomized controlled trial(RCT) of acupuncture-moxibustion treatment for non-specific low back pain by scoping review, so as to demonstrate the current state of the research evidence and provide a reference point for future clinical research and healthcare decision-making. Eight commonly used Chinese and English databases were searched, and the search time was from the establishment of the databases to July 7, 2023, so as to analyze the characteristics of the current status of the current research through visualization methods. A total of 50 studies were included, including 23 studies in Chinese and 27 studies in English. The overall number of studies showed an increasing trend. The percentage of studies published in Chinese non-core journals was 42.0%. The disease subtypes of interest were mainly chronic non-specific low back pain, accounting for 68.0% of the studies. The sample sizes of the studies were mainly concentrated in the range of 50-100 cases. A total of 15 types of interventions were categorized, with acupuncture interventions being the most studied. Duration of treatment did not exceed one month in 80.0% of the studies. Only 8.0% of the studies used minimal clinical important difference(MCID) as a basis for judgment. The follow-up period was set within 3 months in 28.0% of the studies, and 82.0% of the studies concluded that acupuncture-moxibustion was effective in the treatment of non-specific lower back pain. Adverse events were reported in 20.0% of the studies. The risk of bias in the included studies was dominated by low risk of bias and uncertain risk of bias, with fewer studies focusing on high risks of bias. In most of the studies, acupuncture-moxibustion was significantly more effective than the control group. The research on acupuncture-moxibustion treatment for non-specific low back pain is developing rapidly, but there are still insufficient studies on psychological state, safety, and other indicators, and there are still some studies with uncertain risks of bias, which is not conducive to the generalization and application of the findings. Therefore, future studies should improve and refine these shortcomings.
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Terapia por Acupuntura , Dolor de la Región Lumbar , Moxibustión , Humanos , Terapia por Acupuntura/métodos , Dolor de la Región Lumbar/terapia , Dolor de la Región Lumbar/etiología , Moxibustión/métodos , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
To discover PDE4/tubulin dual inhibitors with novel skeleton structures, 7-trimethoxyphenylbenzo[d]oxazoles 4a-u and 4-trimethoxyphenylbenzo[d]oxazoles 5a-h were designed and synthesized by migrating the trimethoxyphenyl group of TH03 to the benzo[d]oxazole moiety. Among these compounds, approximately half of them displayed good antiproliferative activities against glioma (U251) and lung cancer (A549 and H460) cell lines. The structure-activity relationships of trimethoxyphenylbenzo[d]oxazoles led to the identification of 4r bearing indol-5-yl side-chain as a novel dual PDE4/tubulin inhibitor, which exhibited satisfactory antiproliferative activities against glioma (IC50 = 300 ± 50 nM) and lung cancer (average IC50 = 39.5 nM) cells. Further investigations revealed that 4r induced apoptosis at G2/M phase arrest and disrupted the microtubule network. The preliminary mechanism of action showed that 4r down-regulated the expression of cyclin B1 and its upstream regulator gene cdc25C in A549.
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Apoptosis/efectos de los fármacos , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4/metabolismo , Descubrimiento de Drogas , Glioma/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Oxazoles/farmacología , Inhibidores de Fosfodiesterasa 4/farmacología , Moduladores de Tubulina/farmacología , Tubulina (Proteína)/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Glioma/metabolismo , Glioma/patología , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Estructura Molecular , Oxazoles/síntesis química , Oxazoles/química , Inhibidores de Fosfodiesterasa 4/síntesis química , Inhibidores de Fosfodiesterasa 4/química , Relación Estructura-Actividad , Moduladores de Tubulina/síntesis química , Moduladores de Tubulina/química , Células Tumorales CultivadasRESUMEN
To improve the industrial yield of sodium-reduced meat products, we present a feasible method by adjusting water-immersion cooling temperatures to decrease the water loss of pork sausage during processing. The present results showed that the moisture retention capacity of sodium-reduced pork sausages (SRPS) cooled by the temperatures of 15-20 °C was larger than that of 0-10 °C. The higher cooling temperatures, especially at 20 °C, could change the movement and population of proton of inner water, decrease syneresis and facilitate the formation of homogenous cross-linked network, thus increasing the moisture retention of SRPS. Results of this work indicated that the control of cooling temperature of sodium-reduced sausages after cooking could serve as a feasible approach for improving the economic benefits and quality characteristics of the final products.
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Cigarette smoke exposure is the major cause of chronic obstructive pulmonary disease (COPD). Acetylshikonin was the active principle component of Purple Gromwell that show anti-oxidative and anti-inflammatory effect. However, no data are available to elucidate the protective effect of acetylshikonin on COPD. Acetylshikonin could attenuate smoke-induced lung pathological changes, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1ß (IL-1ß), and monocyte chemoattractant protein 1 (MCP-1) productions, and tissue damages caused by oxidative stress. Furthermore, acetylshikonin was found to enhance the expression of Nrf2 and Nur77-mediated COX-2 in vivo and in vitro.
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Neumonía , Humo , Animales , Antraquinonas , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Ratones , Estructura Molecular , Humo/efectos adversos , Fumar/efectos adversosRESUMEN
Osteoarthritis (OA) is a chronic degenerative disease involving multiple physiopathological mechanisms. The increased prevalence of OA after menopause and the presence of estrogen receptors in joint tissues suggest that estrogen could help prevent development of OA. This review summarizes OA research with a focus on the effects of estrogen and selective estrogen receptor modulators (SERMs). Preclinical studies and clinical trials of estrogen therapy have reported inconsistent results. However, almost all studies assessing SERM treatment have obtained more consistent and favorable effects in OA with a relatively safety and tolerability profiles. At present, some SERMs including raloxifene and bazedoxifene have been approved for the treatment of osteoporosis. In summary, estrogen-related agents may exert both a direct effect on subchondral bone and direct and/or indirect effects upon the surrounding tissues, including the articular cartilage, synovium, and muscle, to name a few. Estrogen and SERMs may be particularly favorable for postmenopausal patients with early-stage OA or osteoporotic OA, a phenotype defined by reduced bone mineral density related to high remodeling in subchondral bone. At present, no single drug exists that can prevent OA progression. Although estrogen-related drugs provide insight into the continued work in the field of OA drug administration, further research is required before SERMs can become therapeutic alternatives for OA treatment.
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Osteoartritis/tratamiento farmacológico , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Animales , Femenino , HumanosRESUMEN
BACKGROUND: Intervertebral disc (IVD) degeneration and pathological changes in the spinal cord are major causes of back pain. In addition to its well-established anti-resorptive effect on bone, calcitonin (CT) potentially exerts protective effects on IVD degeneration in ovariectomized rats. However, possible therapeutic effects of CT on lumbar fusion-induced adjacent-segment disc degeneration (ASDD) have not been investigated yet. In this study, we examined the effects of CT on IVD degeneration adjacent to a lumbar fusion in ovariectomized rats. METHODS: Posterolateral lumbar fusion (PLF) at L4-5 was performed 4 weeks after ovariectomy (OVX) or sham surgery in female Sprague-Dawley rats. Following PLF + OVX, rats received either salmon CT (OVX + PLF + sCT, 16 IU/Kg/2d) or vehicle (OVX + PLF + V) treatment for 12 weeks; the remaining rats were divided into Sham + V, OVX + V, and PLF + V groups. Fusion status was analyzed by manual palpation and radiography. Adjacent segment disc was assessed by histological, histomorphometric, immunohistochemical analysis. L6 vertebrae microstructures were evaluated by micro-computed tomography. RESULTS: Histological analysis showed more severe ASDD occurred in OVX + PLF + V rats compared with the OVX + V or PLF + V groups. CT treatment suppressed the score for ASDD, increased disc height, and decreased the area of endplate calcification. Immunohistochemical staining demonstrated that CT decreased the expression of collagen type-I, matrix metalloproteinase-13, and a disintegrin and metalloproteinase with thrombospondin motifs-4, whereas it increased the expression of collagen type-II and aggrecan in the disc. Micro-computed tomography indicated that CT increased bone mass and improved the microstructure of the L6 vertebrae. CONCLUSIONS: These results suggest that CT can prevent ASDD, induce beneficial changes in IVD metabolism, and inhibit deterioration of the trabecular microarchitecture of vertebrae in osteoporotic rats with lumbar fusion.
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Conservadores de la Densidad Ósea/uso terapéutico , Calcitonina/uso terapéutico , Degeneración del Disco Intervertebral/prevención & control , Vértebras Lumbares/efectos de los fármacos , Fusión Vertebral/efectos adversos , Animales , Densidad Ósea , Conservadores de la Densidad Ósea/farmacología , Calcitonina/farmacología , Femenino , Inmunohistoquímica , Degeneración del Disco Intervertebral/etiología , Degeneración del Disco Intervertebral/metabolismo , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/metabolismo , Ovariectomía , Ratas Sprague-Dawley , Microtomografía por Rayos XRESUMEN
PURPOSE: Intervertebral disc degeneration related to postmenopausal osteoporosis is an important issue in spinal disorder research. This study aimed to investigate the effects of salmon calcitonin (sCT), as an antiresorptive medication, on lumbar intervertebral disc degeneration using a rat ovariectomy (OVX) model. METHODS: Thirty 3-month-old female Sprague-Dawley rats were randomly divided into three groups: the sham-operated (Sham) group and two ovariectomized groups treated with vehicle (OVX+V) or sCT (OVX+CT; 16 IU/kg, sc) on alternate days for 6 months. Treatment began after OVX and continued for 6 months. At the end of the experiment, bone mineral density (BMD), micro-CT analysis, biomechanical testing, histology, and immunohistochemistry were performed for all groups. RESULTS: Salmon calcitonin significantly maintained vertebrae BMD, percent bone volume, and biomechanical strength, when compared with the OVX+V group. The changes of mucoid degeneration in the nucleus pulposus and calcification in the middle cartilage endplate were more moderate in the OVX+CT group compared with the OVX+V group, and immunohistochemistry revealed a significant increase in aggrecan and type II collagen expressions, but marked reductions in matrix metalloproteinase (MMP)-1, MMP-3, and MMP-13 expressions in the OVX+CT group. CONCLUSIONS: Salmon calcitonin treatment was effective in delaying the process of the disc degeneration in OVX rats. The underlying mechanisms may be related to preservation of structural integrity and function of vertebrae, and affecting extracellular matrix metabolism by modulating the expressions of MMPs, aggrecan and type II collagen to protect the disc from degeneration.
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Conservadores de la Densidad Ósea/uso terapéutico , Calcitonina/uso terapéutico , Degeneración del Disco Intervertebral/prevención & control , Ovariectomía , Animales , Biomarcadores/metabolismo , Densidad Ósea/efectos de los fármacos , Densidad Ósea/fisiología , Conservadores de la Densidad Ósea/farmacología , Calcitonina/farmacología , Femenino , Degeneración del Disco Intervertebral/etiología , Degeneración del Disco Intervertebral/metabolismo , Distribución Aleatoria , Ratas , Ratas Sprague-DawleyRESUMEN
STUDY DESIGN: A model of disc degeneration adjacent to a lumbar fusion in osteoporotic rats. OBJECTIVE: We determined the effect of alendronate (ALN) on the disc degeneration adjacent to a lumbar fusion in ovariectomized rats. SUMMARY OF BACKGROUND DATA: Adjacent-segment disc degeneration (ASDD) is one of the negative sequelae of spinal fusion. Previous studies have shown that ALN can alleviate disc degeneration. However, no data have been documented regarding the effect of ALN on ASDD after posterolateral lumbar fusion (PLF) in osteoporosis. METHODS: 50 female Sprague-Dawley rats underwent either a sham operation (sham) (n = 20) or bilateral ovariectomy (OVX) (n = 30). 4 weeks later, all but 10 rats from each group underwent PLF consisting of an intertransverse process spinal fusion using autologous-iliac-bone grafts with spinous-process wire fixation at the L4-L5 segment. Animals were subcutaneously administered vehicle (V) or ALN (70 µg/kg/wk) for 12 weeks post-PLF as follows: Sham+V, OVX+V, PLF+V, OVX+PLF+V, and OVX+PLF+ALN. Fusion status was analyzed by manual palpation and radiography. Adjacent-segment disc was assessed by histological, histomorphometric, immunohistochemical, and mRNA analysis. L6 vertebrae microstructures were evaluated by microcomputed tomography. RESULTS: The fused segments showed clear evidence of fusion based on manual palpation and radiographs. The OVX+PLF+V group showed more severe degenerative alterations and higher histological scores in the disc than the Sham+V, OVX+V, and PLF+V groups (P < 0.05). Compared with the OVX+PLF+V group, the OVX+PLF+ALN group exhibited significantly improved bone mass and vertebrae microstructures (P < 0.05), an increased disc height, and a decreased endplate calcification area (P < 0.05). ALN also significantly decreased Col-I, MMP-13, and ADAMTS-4 expression and increased Col-II and Aggrecan expression in the disc matrix (P < 0.05). CONCLUSION: ALN effectively alleviated ASDD post-PLF in ovariectomized rats. These data indicate that ALN can be used as a potential therapeutic agent to attenuate ASDD progression in osteoporosis.
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Alendronato/uso terapéutico , Conservadores de la Densidad Ósea/uso terapéutico , Degeneración del Disco Intervertebral/prevención & control , Vértebras Lumbares/cirugía , Fusión Vertebral/efectos adversos , Alendronato/farmacología , Animales , Densidad Ósea/efectos de los fármacos , Conservadores de la Densidad Ósea/farmacología , Femenino , Disco Intervertebral/efectos de los fármacos , Disco Intervertebral/patología , Degeneración del Disco Intervertebral/etiología , Degeneración del Disco Intervertebral/patología , Ovariectomía , Ratas , Ratas Sprague-DawleyRESUMEN
The Dunkin Hartley (DH) guinea pig is a widely used naturally occurring osteoarthritis model. The aim of this study was to provide detailed evidence of age-related changes in articular cartilage, subchondral bone mineral density, and estradiol levels. We studied the female Dunkin Hartley guinea pigs at 1, 3, 6, 9, and 12 months of age (eight animals in each group). Histological analysis were used to identify degenerative cartilage and electron microscopy was performed to further observe the ultrastructure. Estradiol expression levels in serum were assessed, and matrix metalloproteinase 3 and glycosaminoglycan expression in cartilage was performed by immunohistochemistry. Bone mineral density of the tibia subchondral bone was measured using dual X-ray absorptiometry. Histological analysis showed that the degeneration of articular cartilage grew more severe with increasing age starting at 3 months, coupled with the loss of normal cells and an increase in degenerated cells. Serum estradiol levels increased with age from 1 to 6 months and thereafter remained stable from 6 to 12 months. Matrix metalloproteinase 3 expression in cartilage increased with age, but no significant difference was found in glycosaminoglycan expression between 1- and 3-month old animals. The bone mineral density of the tibia subchondral bone increased with age before reaching a stable value at 9 months of age. Age-related articular cartilage degeneration occurred in Dunkin Hartley guinea pigs beginning at 3 months of age, while no directly positive or negative correlation between osteoarthritis progression and estradiol serum level or subchondral bone mineral density was discovered.
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Estradiol/sangre , Osteoartritis/patología , Envejecimiento , Animales , Densidad Ósea , Cartílago Articular/metabolismo , Cartílago Articular/patología , Femenino , Glicosaminoglicanos/metabolismo , Cobayas , Inmunohistoquímica , Metaloproteinasa 3 de la Matriz/metabolismo , Osteoartritis/metabolismo , Radiografía , Tibia/diagnóstico por imagenRESUMEN
Steam explosion is the most promising technology to replace conventional acid hydrolysis of lignocellulose for biomass pretreatment. In this paper, a new screw-steam-explosive extruder was designed and explored for xylose production and lignocellulose biorefinery at the pilot scale. We investigated the effect of different chemicals on xylose yield in the screw-steam-explosive extrusion process, and the xylose production process was optimized as followings: After pre-impregnation with sulfuric acid at 80 °C for 3 h, corncob was treated at 1.55 MPa with 9 mg sulfuric acid/g dry corncob (DC) for 5.5 min, followed by countercurrent extraction (3 recycles), decoloration (activated carbon dosage 0.07 g/g sugar, 75 °C for 40 min), and ion exchange (2 batches). Using this process, 3.575 kg of crystal xylose was produced from 22 kg corncob, almost 90 % of hemicellulose was released as monomeric sugar, and only a small amount of by-products was released (formic acid, acetic acid, fural, 5-hydroxymethylfurfural, and phenolic compounds were 0.17, 1.14, 0.53, 0.19, and 1.75 g/100 g DC, respectively). All results indicated that the screw-steam-explosive extrusion provides a more effective way to convert hemicellulose into xylose and could be an alternative method to traditional sulfuric acid hydrolysis process for lignocellulose biorefinery.
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Biomasa , Biotecnología/métodos , Residuos Industriales , Xilosa/química , Zea mays/química , Carbono/química , Cristalización , Diseño de Equipo , Concentración de Iones de Hidrógeno , Hidrólisis , Iones , Lignina/química , Fenol/química , Polisacáridos/química , Presión , Vapor , Ácidos Sulfúricos/química , Temperatura , Factores de Tiempo , Aguas ResidualesRESUMEN
OBJECTIVE: To survey the prevalence rate of bronchial asthma in Beijing area among residents aged over 14 years. METHODS: In accordance with stratified cluster random sampling, epidemiological questionnaires were performed in Beijing residents aged over 14 years during household visits from February 2010 to August 2011. Asthma was diagnosed on the basis of case history, clinical signs and lung function test. The statistical software SAS 9.2 was employed to analyze the epidemiological status of asthma. RESULTS: In a sampling population of 61 107, 57 647 questionnaires were effective. Among 687 asthmatics, there were 296 males and 391 females. The overall prevalence rate of asthma was 1.19% (687/57 647). The asthma prevalence rates were 1.09% (418/38 468) and 1.40% (269/19 179) in urban and suburb Beijing respectively and the prevalence rate of asthma in suburb area was significantly higher than that of urban area (χ(2) = 10.850, P = 0.001). The prevalence rates of males and females were 1.06% (296/27 947) and 1.32% (391/29 700) respectively and the prevalence rate of asthma in females was much higher than that of males (χ(2) = 8.098,P = 0.004). Significant differences existed among different age groups (χ(2) = 404.874, P = 0.000) and residents aged at or over 71 years had the highest prevalence rate. The prevalence rates in urban and suburb Beijing area increased by 1.12 and 2.26 folds respectively than that of 2002. And 198 asthmatics were first diagnosed in this survey and accounted for 28.8% (198/687) in all asthma diagnosed asthmatics. CONCLUSIONS: The prevalence rate of asthma in Beijing area among residents aged over 14 years increased greatly from 2010 to 2011. And the epidemiological data may reflect the current distribution status of asthma in Beijing area.
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Asma/epidemiología , Adulto , Anciano , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Encuestas y Cuestionarios , Adulto JovenRESUMEN
RlmM is an AdoMet-dependent methyltransferase that is responsible for 2'-O-methylation of C2498 in the peptidyl-transferase loop of bacterial 23S rRNA. This modification occurs before assembly of the 50S ribosomal subunit, and lack of C2498 methylation can cause a slight reduction in bacterial fitness. Here, the purification and crystallization of RlmM from Escherichia coli as well as its preliminary crystallographic analysis are presented. Cocrystallization of RlmM with AdoMet was carried out and X-ray diffraction data were collected to a resolution of 2.30 Å on beamline BL17U at the SSRF. However, electron density for AdoMet cannot be observed by comprehensive crystallographic analysis, indicating that it is not bound by RlmM during the cocrystallization process. The structure was solved by molecular replacement and refinement is in progress. The crystal contained one molecule in the asymmetric unit and belonged to space group P2(1), with unit-cell parameters a = 56.07, b = 59.38, c = 54.35 Å, ß = 94.84°, which differs from the P3(1) or P3(1)21 space groups of previously reported RlmM structures (PDB entries 4auk, 4atn and 4b17).
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Cristalografía por Rayos X , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/aislamiento & purificación , Escherichia coli , Metiltransferasas/química , Metiltransferasas/aislamiento & purificación , ARN Ribosómico 23S/química , ARN Ribosómico 23S/aislamiento & purificación , Difracción de Rayos XRESUMEN
OBJECTIVE: Increasing evidence has revealed a positive correlation between postmenopausal osteoporosis and intervertebral disc degeneration, the underlying mechanism of which might be associated with changes in the vertebral bone and endplate. Alendronate (ALN) can increase bone mass and improve the microstructure of osteoporotic vertebrae, which might be helpful in preserving disc morphology and mechanical properties. This study aims to investigate the effects of ALN on lumbar intervertebral disc degeneration related to osteoporosis using an ovariectomized (OVX) rat model. METHODS: Thirty female Sprague-Dawley rats aged 3 months were randomly divided into three groups (with 10 rats each) as follows: the Sham group underwent sham surgery; the OVX + ALN group had twice-a-week subcutaneous injections of ALN (15 µg/kg) for 6 months. The OVX + V group received an equivalent volume of saline solution as placebo post-OVX. After animals were sacrificed at 6 months post-OVX, the L3-6 spinal segments were harvested. Bone mineral density (BMD), micro-CT analysis and biomechanical testing were performed to evaluate the bone quality and microstructural changes in the lumbar vertebral bodies. Histological analysis with van Gieson stain and the histological score were used to identify the characteristics of the degenerative discs. The disc height and the thickness of the cartilage endplate were measured and compared. Immunohistochemistry and real-time PCR measurements for aggrecan, type I collagen, type II collagen, and matrix metalloprotease (MMP)-1, MMP-3 and MMP-13 expressions on the disc were performed to assess the underlying molecular signaling changes in matrix metabolism during intervertebral disc degeneration. RESULTS: The OVX + ALN group significantly maintained vertebrae BMD, percent bone volume and biomechanical strength, when compared with the OVX + V group. Histological evaluation suggests that there was no significant difference in disc height between the OVX + ALN and Sham groups, and ALN significantly prevented cartilage endplate thickening and the development of abnormal bony tissues within the cartilage endplate. The histological score in the OVX + ALN group was significantly lower than the OVX + V group, suggesting that ALN treatment was effective in delaying the process of the disc degeneration. The results of molecular analysis revealed a significant increase in aggrecan and type II collagen expressions, but marked reductions in MMP-1, MMP-3 and MMP-13 expressions at both the protein and mRNA levels in the OVX + ALN group. CONCLUSIONS: ALN can retard the progression of lumbar intervertebral disc degeneration in OVX rats. The underlying mechanisms might be related to preservation of the structural integrity and function of the adjacent structures, including the vertebrae and endplates, which further links with modulations in extracellular matrix metabolism to protect the disc from degeneration. These results suggest that ALN might be a promising drug agent for preventing lumbar intervertebral disc degeneration related to osteoporosis.
Asunto(s)
Alendronato/farmacología , Conservadores de la Densidad Ósea/farmacología , Degeneración del Disco Intervertebral/patología , Vértebras Lumbares/efectos de los fármacos , Osteoporosis/prevención & control , Absorciometría de Fotón , Animales , Fenómenos Biomecánicos , Densidad Ósea/efectos de los fármacos , Fuerza Compresiva , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Inmunohistoquímica , Degeneración del Disco Intervertebral/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Osteoporosis/patología , Ovariectomía , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Microtomografía por Rayos XRESUMEN
OBJECTIVE: To determine the feasibility of preservation of intercostobrachial nerve (ICBN) in breast cancer. METHODS: During June 2004 to June 2006, 99 patients with operable breast cancer receiving an axillary lymph node dissection at our department were analyzed. The extirpated ICBN and ambient tissues were tested by HE staining to observe the pathological changes. RESULTS: In 96 (96.97%) cases with ICBN sacrificing, the nerves were not violated microscopically and the nerve cells remained intact. Of 28 patients with axillary lymphadenectasis, only 3 cases (10.71%) were found to have tumor emboli in the peri-neural vessels. CONCLUSION: The preservation of ICBN is a feasible and safe technique. The operative approach should be advocated. If at all possible, a surgeon should identify ICBN and preserve it.
Asunto(s)
Neoplasias de la Mama/cirugía , Carcinoma/cirugía , Nervios Intercostales/cirugía , Escisión del Ganglio Linfático/métodos , Adulto , Anciano , Axila/cirugía , Neoplasias de la Mama/patología , Carcinoma/patología , Estudios de Factibilidad , Femenino , Humanos , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
OBJECTIVE: To detect the differential expression of vascular endothelial growth factor (VEGF) and microvessel density (MVD) count in benign and malignant breast lesions to clarify the correlation of VEGF expression with the occurrence and progression of breast cancer and angiogenesis. METHODS: Immunohistochemistry (SP method) was used to examine the expression of VEGF and MVD count in 88 intra-operatively harvested samples of invasive ductal breast carcinoma, 25 samples of breast carcinoma in situ, 15 samples of atypical breast hyperplasia and 100 samples of benign breast lesions obtained. RESULTS: The positive rate of VEGF in invasive ductal breast carcinoma group was 70.5% and it was significantly higher than those of benign breast lesions, atypical breast hyperplasia and breast carcinoma in situ groups ( 22.0%, 33.3% and 56.0% respectively, P = 0.000). The positive rate of VEGF with lymph node metastasis was higher than that without lymph node metastasis (P = 0.015). The positive rate of VEGF in Stages II b- III was higher than that in Stages I - II a (P = 0.006). The positive rate of VEGF in C-erbB-2 positive group was higher than that in C-erbB-2 negative group (P = 0.016). An elevated expression of VEGF was observed as the tissue differentiation degree increased (P = 0.017). The MVD value of invasive ductal breast carcinoma group was 23 +/- 15 and it was significantly higher than those of benign breast lesions, atypical breast hyperplasia and breast carcinoma in situ groups (14 +/- 4, 18 +/- 4 and 20 +/- 6 respectively, P = 0.000). In invasive ductal breast carcinoma group, a significant higher MVD value was observed as the tissue differentiation degree increased (P = 0.006). The MVD value in VEGF positive group was higher than that in VEGF negative group (P = 0.000). In invasive ductal breast carcinoma, the MVD count increased significantly with the elevated expression of VEGF (P = 0.000). CONCLUSION: In invasive ductal breast carcinoma, angiogenesis and metastasis are mediated mainly by VEGF. The expressions of VEGF and MVD may be two of reference predictors for biological behaviors of breast carcinoma The occurrence and progression of breast cancer might be correlated with the expression of VEGF. The VEGF-targeting antiangiogenic therapy is expected to become a new therapeutic modality for C-erbB-2 positive patients.
Asunto(s)
Neoplasias de la Mama/irrigación sanguínea , Neoplasias de la Mama/patología , Neovascularización Patológica , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Microcirculación , Estadificación de Neoplasias , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Hospitals develop nurse schedules that cover a period of 4-6 weeks and are posted several weeks in advance. Once posted, changes to the schedule require voluntary participation by the nurses, making it difficult for hospitals to respond to changes in nursing needs and availability of nurses. At the same time, nursing needs' forecasts developed several weeks in advance are often wrong. In each hospital setting, there may exist several promising strategies to enhance scheduling flexibility and reduce the mismatch between the nursing needs and the availability of nurses. However, methodologies to evaluate such strategies, before testing them in expensive pilot implementation, do not exist. We demonstrate how such evaluations can be carried out using historical data. Furthermore, we demonstrate the use of our approach by evaluating the benefits of a strategy where nurses are divided into two cohorts and schedules are phase shifted for the two cohorts. Staggering schedules allows nursing unit managers to benefit from more frequent updating of needs' assessments without having to change work rules. Upon applying our approach to data from a large urban hospital, we discovered that in this example staggering did not improve the performance of nurse schedules. We discuss possible reasons for this result, its implications for hospital managers, and other potential uses of our approach.