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Diquat is a kind of conductive contact-killing herbicides. The damage of central nervous system is relatively common, but the peripheral neuropathy caused by diquat has not been reported yet. In September 2021, we treated a patient with diquat poisoning. During the hospitalization, the patient was diagnosed with peripheral neuropathy. Therapy for peripheral nerve injury was given on the basis of conventional treatment of poisoning. The patient was discharged after his condition was stable. The follow-up showed that the peripheral neuropathy of patient was better than before. According to the condition of this patient, it is suggested that we should not only protect the function of gastrointestinal tract, liver, kidney, and central nervous system early, but should also pay attention to the damage of peripheral nervous system in clinical work. We should intervene earlier to improve the prognosis of patients.
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Herbicidas , Traumatismos de los Nervios Periféricos , Intoxicación , Humanos , Diquat , Riñón , HígadoRESUMEN
Objective: To investigate the willingness to use three types of pre-exposure prophylaxis (PrEP) and its associated factors among MSM in Chengdu. Methods: A total of 793 MSM were recruited through Chengdu Tongle Health Consultation Service Centre between November 2021 to January 2022. Data were collected, including demographic characteristics, sexual behaviors in the last six months, PrEP-related stigma, HIV anticipated stigma, MSM internalized stigma, and willingness to use three types of PrEP. Univariate and multivariate logistic regression models were conducted to investigate the associated factors of willingness in using the three types of PrEP. Results: Among 793 participants, willingness to take on-demand PrEP was higher (68.3%). Higher education and multiple sexual partners increased the willingness to use oral PrEP, higher education [compared with junior high school or below, high school or technical secondary school (aOR=2.43, 95%CI: 1.13-5.21), junior college (aOR=2.67, 95%CI: 1.27-5.61), bachelor degree (aOR=3.21, 95%CI: 1.52-6.74), master degree or above (aOR=3.77, 95%CI: 1.54-9.26)], multiple sexual partners (aOR=1.54, 95%CI: 1.12-2.11) were positively associated with daily oral PrEP. HIV anticipated stigma was positively associated with the willingness in using all three types of PrEP: daily oral PrEP (aOR=1.07, 95%CI: 1.02-1.12), on-demand PrEP (aOR=1.09, 95%CI: 1.03-1.15), and injectable PrEP every 8 week (aOR=1.06, 95%CI: 1.01-1.11). Conclusions: The overall willingness in using PrEP in MSM in Chengdu is relatively high, and the promotion of PrEP is highly feasible. In the future, we should continue to promote publicity and education on HIV and PrEP-related knowledge in this population, improve the cognitive level, and guide MSM to establish the correct motivation for PrEP use.
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Infecciones por VIH , Profilaxis Pre-Exposición , Minorías Sexuales y de Género , Masculino , Humanos , Homosexualidad Masculina , Conducta Sexual , Infecciones por VIH/prevención & controlRESUMEN
Gene fusion is one of the mechanisms that promote tumor development. It is also an important cause for the poor prognosis of patients. The detection of gene fusion is crucial for the recognition of tumor biomarker, cancer subtype classification, and clinical medication guidance. Appropriate methods can help the early diagnosis and avoid ineffective medication. Traditional tests include fluorescence in situ hybridization (FISH), immunohistochemistry (IHC), reverse transcription of PCR (RT-PCR), and next generation sequencing (NGS). The next generation sequencing (NGS) mainly includes: whole genome sequencing (WGS), whole transcriptome sequencing (WTS) and target sequencing (hybridization capture method/amplicon method). In clinical concomitant diagnostic applications, some factors such as operability, time/money costs, and the level of expertise required for data analysis should be considered. This article concludes with a discussion of the technical principles of different detection methods and advantages/limitations. Meanwhile, it provides reference opinions for the detection methods of gene fusion.
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Neoplasias Pulmonares , Neoplasias , Humanos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Hibridación Fluorescente in Situ , Neoplasias/genética , Fusión Génica , Tecnología , Neoplasias Pulmonares/diagnósticoRESUMEN
Rice is the most important staple food crop, and it feeds more than half of the world population. Brown planthopper (BPH) is a major insect pest of rice that causes 20-80% yield loss through direct and indirect damage. The identification and use of BPH resistance genes can efficiently manage BPH. A molecular marker-based genetic analysis of BPH resistance was carried out using 101 BC1F5 mapping population derived from a cross between a BPH-resistant indica variety Khazar and an elite BPH-susceptible line Huang-Huan-Zhan. The genetic analysis indicated the existence of Mendelian segregation for BPH resistance. A total of 702 high-quality polymorphic single nucleotide polymorphism (SNP) markers, genotypic data, and precisely estimated BPH scores were used for molecular mapping, which resulted in the identification of the BPH38(t) locus on the long arm of chromosome 1 between SNP markers 693,369 and id 10,112,165 of 496.2 kb in size with LOD of 20.53 and phenotypic variation explained of 35.91%. A total of 71 candidate genes were predicted in the detected locus. Among these candidate genes, LOC_Os01g37260 was found to belong to the FBXL class of F-box protein possessing the LRR domain, which is reported to be involved in biotic stress resistance. Furthermore, background analysis and phenotypic selection resulted in the identification of introgression lines (ILs) possessing at least 90% recurrent parent genome recovery and showing superior performance for several agro-morphological traits. The BPH resistance locus and ILs identified in the present study will be useful in marker-assisted BPH resistance breeding programs.
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Objective: To compare the efficacy and safety profiles of tiotropium/olodaterol with the mono-components in Chinese and total study population from TONADO trial. Methods: In the replicate, double-blind, parallel-group, active-controlled, randomized, 52-week, Phase â ¢ TONADO studies (TONADO 1+2), patients received tiotropium/olodaterol, tiotropium, or olodaterol via the Respimat(®) Inhaler (Boehringer Ingelheim, Germany). Primary end points were forced expiratory volume in 1 second (FEV(1)) area under the curve from 0 to 3 hours (AUC(0-3h)) response and trough FEV(1) response, and St George's respiratory questionnaire (SGRQ) total score at 24 weeks. Adverse events were also collected. This subgroup analysis only focused on the efficacy and safety of the drug at the approved dose in China. Results: 548 Chinese patients were randomized, aged 41 to 82 years [mean age, (63±8) years] and most were male (526, 96%), 111 received tiotropium/olodaterol 5/5 µg, and 127 received tiotropium 5 µg and 95 received olodaterol 5 µg. The baseline characteristics of these groups were similar. After 24 weeks, treatment with tiotropium/olodaterol 5/5 µg, tiotropium 5 µg and olodaterol 5 µg resulted in an adjusted mean FEV(1) AUC(0-3h) response of 0.240, 0.157 and 0.079 L, and trough FEV(1) response of 0.117, 0.068 and-0.001 L, respectively. Tiotropium/olodaterol 5/5 µg significantly improved SGRQ scores in Chinese patients compared with olodaterol 5 µg (32.729 and 37.202, respectively). Generally, the safety profile of tiotropium/olodaterol was comparable with mono-components in 52 weeks. Conclusion: Compared with tiotropium or olodaterol, tiotropium/olodaterol in Chinese patients provided significant improvement in lung function and quality of life, and the safety profiles were similar.
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Benzoxazinas/administración & dosificación , Broncodilatadores/administración & dosificación , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Calidad de Vida , Bromuro de Tiotropio/administración & dosificación , Administración por Inhalación , Agonistas de Receptores Adrenérgicos beta 2 , Adulto , Anciano , Anciano de 80 o más Años , Benzoxazinas/uso terapéutico , Broncodilatadores/uso terapéutico , China/epidemiología , Método Doble Ciego , Volumen Espiratorio Forzado , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/etnología , Enfermedad Pulmonar Obstructiva Crónica/psicología , Bromuro de Tiotropio/uso terapéutico , Resultado del TratamientoRESUMEN
Objective: To observe the effects of mulberry leaf polysaccharide (MLP) on insulin-like growth factor 1 (IGF-1) and insulin-like growth factor blinding protein 3 (IGFBP-3) as well as the expression of IGF-1 and IGFBP-3 mRNA in the kidney of type 1 Diabetic Nephropathy (DN) rats, and to investigate its therapeutic effects and underlying mechanisms. Methods: Type 1 DN rat model was established by intraperitoneally injecting streptozocin (STZ). SD rats were randomly divided into the control, model, insulin and MLP groups, with eight rats in each group. Rats in MLP group were given orally with MLP 200 mg/kg daily for 8 weeks and insulin group rats were given subcutaneously injection of short acting insulin 1 U daily for 8 weeks. The changes in body weight, blood and urine parameters were recorded. Extracellular matrix (ECM) was calculated. The contents of IGF-1 and IGFBP-3 in blood serum were evaluated by enzyme-linked immunosorbent assay (ELISA). The mRNA expressions of IGF-1 and IGFBP-3 in the kidney were evaluated by fluorescence quantitative PCR. Results: Compared with rats in control group, blood glucose, triglyceride, total cholesterol, low density lipoprotein, very low density lipoprotein, 24 h urine protein, serum creatinine and urea nitrogen in the model group rats were significantly increased (all P<0.01), and these parameters of MLP group were significantly lower than the model group (all P<0.01). The contents of IGF-1 and IGFBP-3 in the blood serum of the model group were significantly higher than those in the control group (both P<0.001), while in the MLP group they were lower than the model group[IGF-1: (0.777±0.018) ng/ml vs (0.864±0.022) ng/ml, P<0.001; IGFBP-3: (0.759±0.016) ng/ml vs (0.846±0.021) ng/ml, P<0.001]. The mRNA expressions of IGF-1 and IGFBP-3 in the kidney of the model group were significantly higher than those in the control group (both P<0.001), while in the MLP group they were lower than in the model group (IGF-1: 1.450±0.032 vs 1.810±0.090, P<0.001; IGFBP-3: 1.684±0.018 vs 1.968±0.044, P<0.001). Compared with the model group rats, there were fewer pathological changes of kidney in MLP group rats. Conclusion: MLP has a certain therapeutic effect on DN, which may be achieved by decreasing the contents of IGF-1 and IGFBP-3 in the blood serum and down-regulating the over-expression of IGF-1 and IGFBP-3 mRNA in the kidney.
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Morus , Animales , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Nefropatías Diabéticas , Factor I del Crecimiento Similar a la Insulina , Polisacáridos , Ratas , Ratas Sprague-DawleyRESUMEN
Pseudomonas aeruginosa is one of the common colonizing bacteria of the human body and is an opportunistic pathogen frequently associated with respiratory infections. Inactivated P. aeruginosa (IPA) have a variety of biological effects against inflammation and allergy. Transforming growth factor-ß (TGF-ß) signaling plays a critical role in the regulation of cell growth, differentiation, and development in a wide range of biological systems. The present study was designed to investigate the effects of IPA on TGF-ß/Smad signaling in vivo, using a hypoxia-induced pulmonary hypertension (PH) rat model. Sprague Dawley rats (n=40) were exposed to 10% oxygen for 21 days to induce PH. At the same time, IPA was administered intravenously from day 1 to day 14. Mean pulmonary artery pressure (mPAP) and the right ventricle (RV) to left ventricle plus the interventricular septum (LV+S) mass ratio were used to evaluate the development of PH. Vessel thickness and density were measured using immunohistochemistry. Primary arterial smooth muscle cells (PASMCs) were isolated and the proliferation of PASMCs was assayed by flow cytometry. The production of TGF-ß1 in cultured supernatant of PASMCs was assayed by ELISA. The expression levels of α-smooth muscle actin (α-SMA), TGF-ß1 and phospho-Smad 2/3 in PASMCs were assayed by western blot. Our data indicated that IPA attenuated PH, RV hypertrophy and pulmonary vascular remodeling in rats, which was probably mediated by restraining the hypoxia-induced overactive TGF-ß1/Smad signaling. In conclusion, IPA is a promising protective treatment in PH due to the inhibiting effects on TGF-ß1/Smad 2/3 signaling.
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Hipertensión Pulmonar/metabolismo , Hipertensión Pulmonar/prevención & control , Hipoxia/metabolismo , Miocitos del Músculo Liso/fisiología , Pseudomonas aeruginosa/fisiología , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Actinas/análisis , Actinas/metabolismo , Animales , Western Blotting , Proliferación Celular/fisiología , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Hipertensión Pulmonar/etiología , Hipoxia/complicaciones , Inmunohistoquímica , Masculino , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Transducción de Señal/fisiología , Proteínas Smad/análisis , Factor de Crecimiento Transformador beta1/análisisRESUMEN
UDP-glucuronate decarboxylase (UDP-xylose synthase; UXS, EC 4.1.1.35) is an essential enzyme of the non-cellulosic polysaccharide biosynthetic pathway. In the present study, using transient expression of fluorescently labeled Gossypium hirsutum UXS (GhUXS3) protein in onion epidermal cells, we observed that this protein was distributed in the cytoplasm. The GhUXS3 cDNA of cotton was expressed in an antisense orientation in Arabidopsis thaliana by Agrobacterium tumefaciens-mediated transformation. Homozygous plants showing down-regulation of UXS were analyzed with northern blots. Compared to the untransformed control, transgenic plant showed shorter roots, earlier blossom formation, and delayed senescence. Biochemical analysis indicated that levels of rhamnose, mannose, galactose, glucose, xylose, and cellulose were reduced in some of the down-regulated antisense plants. These results suggest that GhUXS3 regulates the conversion of non-cellulosic polysaccharides and modulates their composition in plant cell walls. We also discuss a possible cellular function for GhUXS in determining the quality of cotton fibers.
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Arabidopsis/genética , Metabolismo de los Hidratos de Carbono/genética , Carboxiliasas/genética , Pared Celular/metabolismo , ADN sin Sentido , Gossypium/enzimología , Envejecimiento , Arabidopsis/metabolismo , Arabidopsis/fisiología , Pared Celular/química , ADN de Plantas , Flores/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Gossypium/genética , Raíces de Plantas/anatomía & histología , Plantas Modificadas GenéticamenteRESUMEN
Corn DNA was introduced into dry seeds of rice (cv. 'YuJing-6') by ion beam irradiation. Proteinase activities in rice seedling roots were subsequently analyzed by renaturation electrophoresis at pH 4.5, 7.0, and 8.5. Proteinase activity was more pronounced on gels at higher pH. Irradiation of rice seedling roots caused the loss of some proteinase bands at all pH conditions although a novel 50-kDa band was found at both pH 7.0 and 8.5. No new proteinase activity was detected at pH 4.5. However, novel bands and bands showing stronger activity were observed at pH 7.0 and 8.5. The data indicate that the expression of proteinases in rice seedling roots was altered following low energy ion beam mediated transformation with corn DNA.
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ADN de Plantas/genética , Oryza/genética , Péptido Hidrolasas/metabolismo , Proteínas de Plantas/metabolismo , Semillas/genética , Transformación Genética , Zea mays/química , Electroforesis en Gel de Poliacrilamida , Pruebas de Enzimas , Expresión Génica , Concentración de Iones de Hidrógeno , Iones , Cinética , Nitrógeno/química , Oryza/enzimología , Péptido Hidrolasas/genética , Proteínas de Plantas/genética , Raíces de Plantas/enzimología , Raíces de Plantas/genética , Radiación no Ionizante , Plantones/enzimología , Plantones/genética , Semillas/enzimologíaRESUMEN
To optimize the combination of microsatellite loci for genetic control of outbred swine stocks, 32 of 100 loci distributed among almost all chromosomes (except 12) were screened out by 1.5% agarose, 8% polyacrylamide gel and capillary electrophoresis scanning among 3 miniature swine outbred stocks, namely Bama (BM), Guizhou (GZ) and Tibeta (TB). The mean total and effective allele numbers among these stocks were 12.1 and 5.9, respectively. The mean heterozygosity for these breeds was 0.5428, 0.6978 and 0.7646, and polymorphism information content was 0.5469, 0.7296 and 0.7663, respectively. Accordingly, hereditary variation from low to high was BM < GZ < TB. This showed that the genetic relationship between BM and GZ pigs was closer, and both were distant from TB. Additionally, the effectiveness of the 32-locus combination for evaluation of genetic quality was demonstrated in Changchun-junmo-1 (CJ-1), a standard outbred Chinese pig stock, in which the mean total and effective allele numbers and mean heterozygosity were 6.1613, 3.8483 and 0.6903, respectively. Since our results were consistent with the breeding pedigrees, the 32 loci could be used for both genetic monitoring within the individual outbred miniature swine stocks and population structure analysis between them.
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Genética de Población , Repeticiones de Microsatélite/genética , Porcinos Enanos/genética , Porcinos/genética , Animales , Electroforesis/métodos , Heterocigoto , Polimorfismo GenéticoRESUMEN
The interaction between active element Zr and W damages the W fibers and the interface and decreases the mechanical properties, especially the tensile strength of the W fibers reinforced Zr-based bulk metallic glass composites (BMGCs). From the viewpoint of atomic interaction, the W-Zr interaction can be restrained by adding minor elements that have stronger interaction with W into the alloy. The calculation about atomic interaction energy indicates that Ta and Nb preferred to segregate on the W substrate surface. Sessile drop experiment proves the prediction and corresponding in-situ coating appears at the interface. Besides, the atomic interaction mechanism was proven to be effective in many other systems by the sessile drop technique. Considering the interfacial morphology, Nb was added into the alloy to fabricate W/Zr-based BMGCs. As expected, the Nb addition effectively suppressed the W-Zr reaction and damage to W fibers. Both the compressive and tensile properties are improved obviously.
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Rice variation induced by the introduction of exogenous DNA has become an important method of improving rice varieties and creating new germplasms. In this study, we transferred maize genomic DNA fragments to the receptor of Nipponbare rice using a modified "pollen-tube pathway" method. Material from mutant rice B1 and B2 were acquired and 14 specific bands were obtained from the material using amplified fragment length polymorphism analysis. From the 14 specific sequences obtained, there were 3791 bp, including 144 base mutations with a base mutation rate of 3.80%. Specific bands resulted from base mutation of selective bases or restriction endonuclease recognition sequences, or insertion or deletion of DNA fragments. The frequency of single-base mutations was significantly higher than that of double-base mutations, three-sequential base mutations, and multiple-sequential base mutations. The site frequency of base substitution (87.04%) was significantly higher than that of base insertion (3.70%) or deletion (9.26%). In all cases of base substitution, the frequency of transition (76.47%) was significantly higher than transversion (23.53%). The above results indicate that transferring foreign-species DNA into rice cells can induce base mutations in the receptor, with base substitutions occurring at the highest frequency, and the dominant type of base substitutions being transition. Preliminary analysis reveals that the molecular mechanism of transferring exogenous DNA into rice causes mutations, which provides theoretical data on biological mutagenesis for further research.
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Oryza/genética , Plantas Modificadas Genéticamente/genética , Zea mays/genética , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Análisis Mutacional de ADN , ADN de Plantas/genética , Genes de Plantas , Mutación INDELRESUMEN
Biomass yield is one of the most important traits for wheat (Triticum aestivum L.)-breeding programs. Increasing the yield of the aerial parts of wheat varieties will be an integral component of future wheat improvement; however, little is known regarding the genetic control of aerial part yield. A doubled haploid population, comprising 168 lines derived from a cross between two winter wheat cultivars, 'Huapei 3' (HP3) and 'Yumai 57' (YM57), was investigated. Quantitative trait loci (QTL) for total biomass yield, grain yield, and straw yield were determined for additive effects and additive x additive epistatic interactions using the QTLNetwork 2.0 software based on the mixed-linear model. Thirteen QTL were determined to have significant additive effects for the three yield traits, of which six also exhibited epistatic effects. Eleven significant additive x additive interactions were detected, of which seven occurred between QTL showing epistatic effects only, two occurred between QTL showing epistatic effects and additive effects, and two occurred between QTL with additive effects. These QTL explained 1.20 to 10.87% of the total phenotypic variation. The QTL with an allele originating from YM57 on chromosome 4B and another QTL contributed by HP3 alleles on chromosome 4D were simultaneously detected on the same or adjacent chromosome intervals for the three traits in two environments. Most of the repeatedly detected QTL across environments were not significant (P > 0.05). These results have implications for selection strategies in wheat biomass yield and for increasing the yield of the aerial part of wheat.
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Biomasa , Mapeo Cromosómico , Epistasis Genética , Haploidia , Sitios de Carácter Cuantitativo , Triticum/fisiología , Cruzamientos Genéticos , Ligamiento Genético , Fenotipo , Carácter Cuantitativo HeredableRESUMEN
Estimations of genetic diversity and of relationships between varieties are crucial for cotton breeding. The genetic diversity of 59 core cotton cultivars, most of which were collected from China's main cotton-growing areas, was analyzed based on genomic and newly developed expressed sequence tag-derived microsatellite markers, using total DNA extracted from fresh leaf tissue. Three hundred and two fragments were detected, of which 255 were polymorphic. The number of amplification products generated by each primer varied from 2 to 14, with a mean of 5.08 bands/primer. The polymorphism information content was 0.50 to 0.90, with a mean of 0.80. The genetic similarity coefficients were calculated and dendrograms were constructed by the unweighted pair group with arithmetic mean method; the resulting distance matrix gave a dendrogram with four main clusters. Some cultivars with similar pedigrees could be clustered. For example, Zhong206 and Shanmian4, both derived from Deltapine15, were clustered. The genetic similarity coefficient of the 59 core cultivars ranged from 0.53 to 0.99, with a mean of 0.72, indicating that there was a relatively high level of genetic variation.
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Etiquetas de Secuencia Expresada , Variación Genética/genética , Repeticiones de Microsatélite/genética , ADN de Plantas/genética , Gossypium/genética , FilogeniaRESUMEN
PURPOSE: symptomatic cerebral vasospasm (SCVS) is still lacking in reliable early warning methods and often diagnosed after clinical deterioration of neurological function, making prevention and treatment extremely passive. This study investigates the risk factors relevant to SCVS after subarachnoid hemorrhage (SAH) in order to provide useful information for clinical work. MATERIALS AND METHODS: clinical data of 211 patients with SAH was reviewed in this study. 16 risk factors relevant to SCVS were retrospectively analyzed, including univariate analysis and logistic analysis. RESULTS: of 211 patients, 81 were found to have SCVS (38.4%). Univariate analysis showed that age, history of hypertension, Hunt-Hess grade at admission, modified Fisher grade, aneurysm location, fever and intraventricular blood clot reached statistical significance (P < 0.05), suggesting that they might be risk factors to SCVS. However, logistic analysis showed that only age (OR=1.027, 95% CI=1.002-1.053, P < 0.05) and modified Fisher grade (OR=2.985, 95% CI=2.048-4.352, P < 0.05) entered the regression equation, suggesting both were independent risk factors. CONCLUSIONS: SCVS is the final result of multiple factors acting together. Age and modified Fisher grades are independent risk factors to SCVS.
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Hemorragia Subaracnoidea/complicaciones , Vasoespasmo Intracraneal/diagnóstico , Vasoespasmo Intracraneal/etiología , Adulto , Anciano , Análisis de Varianza , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la EnfermedadRESUMEN
Drought is the most important factor limiting rice productivity in the rainfed areas of Asia. In this study, 48 pyramiding lines (PLs) and their recurrent parent, IR64, were evaluated over two years for their yield performances and related traits under severe drought stress at the reproductive stage (RS), the vegetative stage (VS) and irrigated control in order to understand the relationship between drought tolerance (DT) and yield potential (YP) in rice and their underlying mechanisms. When compared with IR64, all PLs had significantly improved DT to RS and 36 PLs also had significantly improved DT to VS. In addition, 17 PLs had higher YP than IR64 and the remaining 31 PLs had a similar YP IR64 under irrigated conditions. Detailed characterization of the PLs revealed three possible mechanisms that functioned together to contribute to their improved DT. The most important mechanism was dehydration avoidance (DA), characterized by significantly higher growth rate and biomass of all PLs than IR64 under stress and no reduction in biomass under control conditions. The second mechanism was efficient partitioning, characterized by improved harvest index in all PLs compared with IR64, resulting primarily from heavier grain weight and/or higher spikelet fertility under control conditions, which was the major constituent of the improved YP in the 17 best performing PLs. Drought escape (DE) by accelerated heading under drought was the third mechanism that contributed to DT of the PLs to RS. The considerable variation in the measured traits among the PLs with similar levels of DT and YP implies the complex genetic control of the mechanisms for DT/YP and offers opportunities to improve DT and YP further by fine-tuning of a small number of QTLs segregating among the PLs using MAS. Finally, our results indicate that selection for yield plus some secondary traits under appropriate type(s) of stress and non-stress conditions similar to the target environments are critically important for improving both DT and YP in rice.
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Sequías , Oryza/crecimiento & desarrollo , Estrés Fisiológico , Análisis de Varianza , Cruzamiento , Cruzamientos Genéticos , Análisis de los Mínimos Cuadrados , Semillas/crecimiento & desarrolloRESUMEN
Previous studies have demonstrated that bone marrow-derived mesenchymal stem cell (MSC) engraftment attenuated lung injury in a model induced by bleomycin in mice. However, the mechanisms are not completely understood. The primary objective of the present study was to determine whether MSC engraftment can also protect lungs against bleomycin-induced injury in rats and to observe any beneficial effects of cytokines. Twelve hours after bleomycin (5 mg/kg) or phosphate-buffered saline was perfused into the trachea, 5x10(6) DAPI-labeled MSCs or DMEM-F12 were injected into the tail vein of rats. Two weeks later, MSCs labeled with DAPI were detected by pan-cytokeratin staining. The level of laminin and hyaluronan in bronchoalveolar lavage fluid was measured by radioimmunoassay. Collagen content in lung tissue was calculated by the hydroxyproline assay. TGF-beta1, PDGF-A, B, and IGF-I were measured by real-time PCR. It was observed that some MSCs positive for pan-cytokeratin staining, an indicator of alveolar epithelial cells, were present in injured lung tissue. Bleomycin injection increased the content of hydroxyproline in lung tissue, as well as laminin and hyaluronan in bronchoalveolar lavage fluid, markers for lung injury and fibrosis. However, these effects were attenuated by MSC treatment. Furthermore, the increased mRNA levels of TGF-beta1, PDGF-A, PDGF-B, and IGF-I following bleomycin injection were also significantly decreased by MSC treatment. These observations provided evidence that MSCs are still present in the lung 2 weeks after the initial MSC treatment in rats, as well as documented the beneficial effects of MSC engraftment against bleomycin-induced lung injury associated with changes in TGF-beta1, PDGF-A, PDGF-B, and IGF-I. These results may provide an experimental base for clinical therapy of pulmonary fibrosis in the future.