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1.
IEEE Trans Biomed Eng ; PP2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38935473

RESUMEN

OBJECTIVE: The high prevalence of osteoarthritis emphasizes the need for a cost-effective and accessible method for its early diagnosis. Recently, the portability and affordability of very-low-field (VLF) magnetic resonance imaging (MRI, 10-100 mT) have caused it to gain popularity. Nevertheless, there is insufficient evidence to quantify early degenerative changes in cartilage using VLF MRI. This study assessed the potential of T1ρ and T2 mapping for detecting degenerative changes in porcine cartilage specimens using a 50 mT MRI scanner. METHODS: T2- and T1ρ-weighted images were acquired using a 50 mT MRI scanner with 2D spin-echo and triple-refocused T1ρ preparation sequences. MRI scans of porcine cartilage were also acquired using a 3 T MRI scanner for comparison. A mono-exponential algorithm was applied to fit a series of T2- and T1ρ-weighted images. T2 values for CuSO4·5H2O solutions measured via Carr-Purcell-Meiboom-Gill (CPMG) and spin-echo sequences were compared to verify the algorithm's reliability. The nonparametric Kruskal-Wallis statistical test was used to compare T2 and T1ρ values. Experimental repeatability was assessed using the root-mean-square of the coefficient of variation (rmsCV). RESULTS: T2 values of the CuSO4·5H2O solutions obtained using the spin-echo sequence showed differences within 2.3% of those obtained using the CPMG sequence, indicating the algorithm's reliability. The T1ρ values for varying concentrations of agarose gel solutions were higher than the T2 values. Furthermore, 50 mT and 3 T MRI results showed that both the T1ρ and T2 values were significantly higher for porcine cartilage degraded for 6 h vs intact cartilage, with p-values of 0.006 and 0.01, respectively. Our experimental results showed good reproducibility (rmsCV < 8%). CONCLUSION: We demonstrated the feasibility of quantitative cartilage imaging via T2 and T1ρ mapping at 50 mT MRI for the first time.

2.
IEEE Trans Biomed Eng ; 71(5): 1687-1696, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38150336

RESUMEN

OBJECTIVE: The Dixon method is frequently employed in clinical and scientific research for fat suppression, because it has lower sensitivity to static magnetic field inhomogeneity compared to chemical shift selective saturation or its variants and maintains image signal-to-noise ratio (SNR). Recently, research on very-low-field (VLF < 100 mT) magnetic resonance imaging (MRI) has regained popularity. However, there is limited literature on water-fat separation in VLF MRI. Here, we present a modified two-point Dixon method specifically designed for VLF MRI. METHODS: Most experiments were performed on a homemade 50 mT portable MRI scanner. The receiving coil adopted a homemade quadrature receiving coil. The data were acquired using spin-echo and gradient-echo sequences. We considered the T2* effect, and added priori information to existing two-point Dixon method. Then, the method used regional iterative phasor extraction (RIPE) to extract the error phasor. Finally, least squares solutions for water and fat were obtained and fat signal fraction was calculated. RESULTS: For phantom evaluation, water-only and fat-only images were obtained and the local fat signal fractions were calculated, with two samples being 0.94 and 0.93, respectively. For knee imaging, cartilage, muscle and fat could be clearly distinguished. The water-only images were able to highlight areas such as cartilage that could not be easily distinguished without separation. CONCLUSION: This work has demonstrated the feasibility of using a 50 mT MRI scanner for water-fat separation. SIGNIFICANCE: To the best of our knowledge, this is the first reported result of water-fat separation at a 50 mT portable MRI scanner.


Asunto(s)
Tejido Adiposo , Imagen por Resonancia Magnética , Fantasmas de Imagen , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/instrumentación , Humanos , Tejido Adiposo/diagnóstico por imagen , Agua Corporal/diagnóstico por imagen , Rodilla/diagnóstico por imagen , Articulación de la Rodilla/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Diseño de Equipo
3.
New Phytol ; 240(6): 2436-2454, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37840365

RESUMEN

Seed size and weight are important factors that influence soybean yield. Combining the weighted gene co-expression network analysis (WGCNA) of 45 soybean accessions and gene dynamic changes in seeds at seven developmental stages, we identified candidate genes that may control the seed size/weight. Among these, a PLATZ-type regulator overlapping with 10 seed weight QTLs was further investigated. This zinc-finger transcriptional regulator, named as GmPLATZ, is required for the promotion of seed size and weight in soybean. The GmPLATZ may exert its functions through direct binding to the promoters and activation of the expression of cyclin genes and GmGA20OX for cell proliferation. Overexpression of the GmGA20OX enhanced seed size/weight in soybean. We further found that the GmPLATZ binds to a 32-bp sequence containing a core palindromic element AATGCGCATT. Spacing of the flanking sequences beyond the core element facilitated GmPLATZ binding. An elite haplotype Hap3 was also identified to have higher promoter activity and correlated with higher gene expression and higher seed weight. Orthologues of the GmPLATZ from rice and Arabidopsis play similar roles in seeds. Our study reveals a novel module of GmPLATZ-GmGA20OX/cyclins in regulating seed size and weight and provides valuable targets for breeding of crops with desirable agronomic traits.


Asunto(s)
Glycine max , Transcriptoma , Glycine max/genética , Transcriptoma/genética , Fitomejoramiento , Sitios de Carácter Cuantitativo , Semillas/genética
4.
Sensors (Basel) ; 23(10)2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37430578

RESUMEN

Nuclear magnetic resonance (NMR) magnetometers are considered due to their ability to map magnetic fields with high precision and calibrate other magnetic field measurement devices. However, the low signal-to-noise ratio of low-strength magnetic fields limits the precision when measuring magnetic fields below 40 mT. Therefore, we developed a new NMR magnetometer that combines the dynamic nuclear polarization (DNP) technique with pulsed NMR. The dynamic pre-polarization technique enhances the SNR under a low magnetic field. Pulsed NMR was used in conjunction with DNP to improve measurement accuracy and speed. The efficacy of this approach was validated through simulation and analysis of the measurement process. Next, a complete set of equipment was constructed, and we successfully measured magnetic fields of 30 mT and 8 mT with an accuracy of only 0.5 Hz (11 nT) at 30 mT (0.4 ppm) and 1 Hz (22 nT) at 8mT (3 ppm).

5.
Phytopathology ; 113(3): 448-459, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36224750

RESUMEN

Early forecasting of rice panicle blast is critical to the management of rice blast. To develop early forecasting models for rice panicle blast, the relationship between the seasonal maximum incidence of rice panicle blast (PBx) and the PBx in the preceding crop, weather conditions, location, and acreage of susceptible varieties was analyzed. Results revealed that PBx in the preceding crop, acreage of the susceptible varieties in class (SVC), altitude, weather conditions 120 to 180 days before the PBx date (dbPBx) and 30 to 90 dbPBx were significantly correlated with the PBx. Subsequently, a logistic model and a two-step hurdle model were developed to predict rice panicle blast. The logistic model was developed to predict whether the PBx was 0 or not based on the preceding PBx, altitude, acreage of susceptible varieties, the longest stretch of days with soil temperatures between 16 and 24°C for the period 120 to 150 dbPBx, and the longest stretch of rainy days in the period 120 to 180 dbPBx. The hurdle model predicted if the PBx was greater than 0 at the first step, and if the prediction was greater than 0, then a regression model was developed for predicting PBx based on the preceding PBx, SVC, altitude, and weather data 180 to 30 dbPBx. Validation with the test datasets showed that the logistic model could correctly predict whether PBx was 0 at a mean test accuracy of 78.39% and that the absolute prediction error of PBx by the two-step hurdle model was smaller than 6.16% for 90% of the records. The model developed in this study will be helpful in management decisions for rice growers and policy makers and offer a useful basis for further studies on the epidemiology and forecasting of rice panicle blast.


Asunto(s)
Oryza , Incidencia , Enfermedades de las Plantas , Tiempo (Meteorología) , China/epidemiología
6.
Asian J Androl ; 25(1): 13-20, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35435336

RESUMEN

Infertility has become a serious disease since it affects 10%-15% of couples worldwide, and male infertility contributes to about 50% of the cases. Notably, a significant decrease occurs in the newborn population by 7.82 million in 2020 compared to 2016 in China. As such, it is essential to explore the effective methods of obtaining functional male gametes for restoring male fertility. Stem cells, including embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), spermatogonial stem cells (SSCs), and mesenchymal stem cells (MSCs), possess the abilities of both self-renewal and differentiation into germ cells. Significantly, much progress has recently been achieved in the generation of male germ cells in vitro from various kinds of stem cells under the specified conditions, e.g., the coculturing with Sertoli cells, three-dimensional culture system, the addition of growth factors and cytokines, and/or the overexpression of germ cell-related genes. In this review, we address the current advance in the derivation of male germ cells in vitro from stem cells based on the studies of the peers and us, and we highlight the perspectives and potential application of stem cell-derived male gametes in reproductive medicine.


Asunto(s)
Células Madre Pluripotentes Inducidas , Infertilidad Masculina , Humanos , Recién Nacido , Masculino , Células Germinativas , Células Madre Embrionarias , Diferenciación Celular
7.
Zhongguo Zhong Yao Za Zhi ; 47(18): 4908-4918, 2022 Sep.
Artículo en Chino | MEDLINE | ID: mdl-36164900

RESUMEN

With prominent medicinal value, Gelsemium elegans has been overexploited, resulting in the reduction of the wild resource. As a result, artificial cultivation turns out to be a solution. However, this medicinal species is intolerant to low temperature, and thus genes responding to the low temperature are important for the cultivation of this species. Based on the transcriptome database of G. elegans at 4 ℃, 29 differentially expressed GeERF genes were identified. Bioinformatics analysis of 21 GeERF gene sequences with intact open reading frames showed that 12 and 9 of the GeERF proteins respectively clustered in DREB subgroup and ERF subgroup. GeDREB1 A-1-GeERF6 B-1, with molecular weight of 23.78-50.96 kDa and length of 212-459 aa, were all predicted to be hydrophilic and in nucleus. Furthermore, the full-length cDNA sequence of GeERF2B-1 was cloned from the leaves of G. elegans. Subcellular localization suggested that GeERF2B-1 was located in the nucleus. According to the quantitative reverse-transcription PCR(qRT-PCR), GeERF2B-1 showed constitutive expression in roots, stems, and leaves of G. elegans, and the expression was the highest in roots. In terms of the response to 4 ℃ treatment, the expression of GeERF2B-1 was significantly higher than that in the control and peaked at 12 h, suggesting a positive response to low temperature. This study lays a scientific basis for the functional study of GeERF transcription factors and provides gene resources for the improvement of stress resistance of G. elegans.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Factores de Transcripción , ADN Complementario , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Temperatura , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
8.
Molecules ; 27(11)2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35684349

RESUMEN

In this research, the composition of free phenols, bound phenols, and anthocyanins and their in vitro antioxidant activity and in vitro α-glucosidase inhibiting activity were observed in different barley colors. The outcomes revealed that the contents of total phenols (570.78 mg/100 gDW), total flavonoids (47.08 mg/100 gDW), and anthocyanins (48.07 mg/100 g) were the highest in purple barley. Furthermore, the structure, composition, and concentration of phenolics differed depending on the colors of barley. The types and contents of bound total phenolic acids and flavonoids were greater than those of free total phenolic acids and flavonoids. The main phenolic acids in blue barley were cinnamic acid polyphenols, whereas in black, yellow, and purple barley, benzoic acid polyphenols were the main phenolic acids, and the main types of flavonoids in black and blue barley were chalcones and flavanones, respectively, whereas flavonol was the main type of flavonoid in yellow and purple barley. Moreover, cornflower pigment-3-glucoside was the major anthocyanin in blue, yellow, and purple barley, whereas the main anthocyanin in black barley was delphinidin-3-glucoside. The dark color of barley indicated richness in the anthocyanins. In addition, the free polyphenol fractions had stronger DPPH and ABTS radical scavenging capacity as compared to the bound ones. In vitro α-glucosidase-inhibiting activity was greater in bound polyphenols than in free polyphenols, with differences between different varieties of barley. Purple barley phenolic fractions had the greatest ABTS radical scavenging and iron ion reduction capacities, as well as the highest α-glucosidase-inhibiting activity. The strongest DPPH radical scavenging capacity was found in yellow barley, while the strongest in vitro α-glucosidase-inhibiting activity was found in anthocyanins isolated from black barley. Furthermore, in different colors of barley, there was a strong association between the concentration of specific phenolic compounds and antioxidant and α-glucosidase-inhibiting activities. The outcomes of this study revealed that all colored barley seeds tested were high in phenolic compounds, and had a good antioxidant impact and α-glucosidase-inhibiting activity. As a result, colored barley can serve as an antioxidant and hypoglycemic food. Polyphenols extracted from purple barley and anthocyanins extracted from black barley stand out among them.


Asunto(s)
Antocianinas , Hordeum , Antocianinas/farmacología , Antioxidantes/farmacología , Color , Flavonoides/farmacología , Hordeum/química , Fenoles , Polifenoles/farmacología , alfa-Glucosidasas
9.
Pediatr Blood Cancer ; 68(5): e28858, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33501733

RESUMEN

BACKGROUND: Delayed excretion of methotrexate can lead to life-threatening toxicity that may result in treatment cessation, irreversible organ damage, and death. Various factors have been demonstrated to influence the pharmacokinetic process of methotrexate, including genetic and nongenetic factors. METHODS: We investigated the genetic factors primarily related to the metabolic pathway of methotrexate in children with acute lymphoblastic leukemia with delayed elimination, defined as C44-48h ≥ 1.0µmol/L in this study. A total of 196 patients (delayed excretion group: 98; normal excretion group: 98) who received CCCG-ALL-2015 protocol after propensity score-matched analysis were included in the study. Twenty-eight target single-nucleotide polymorphisms (SNPs) were analyzed by multiplex polymerase chain reaction and sequencing, and 25 SNPs were finally included in the study. RESULTS: The genotype distribution of SLCO1B1 rs2306283 SNP was different between the delayed and normal excretion groups. SLCO1B1 rs2306283 AA carriers had a significantly lower methotrexate C44-48h /D ratio than GG carriers in both groups. Furthermore, compared with the normal excretion group, SLCO1B1 rs2306283 AG and GG were risk factors for developing oral mucositis (odds ratio [OR]: 2.13; 95% confidence interval [CI]: 1.11-4.08; P < .001), hepatotoxicity (OR: 2.12; 95% CI: 1.26-3.56; P < .001), and myelosuppression (OR: 1.21; 95% CI: 1.04-1.41; P = .005) in delayed excretion group. CONCLUSIONS: The results from this study indicate the potential role of SLCO1B1 rs2306283 as a pharmacogenomic marker to guide and optimize methotrexate treatment for delayed elimination in children with acute lymphoblastic leukemia.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacocinética , Transportador 1 de Anión Orgánico Específico del Hígado/genética , Metotrexato/farmacocinética , Variantes Farmacogenómicas/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Adolescente , Antimetabolitos Antineoplásicos/metabolismo , Niño , Preescolar , Femenino , Genotipo , Humanos , Masculino , Metotrexato/metabolismo , Polimorfismo de Nucleótido Simple , Estudios Retrospectivos
10.
Clin Transplant ; 34(11): e14051, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32946605

RESUMEN

BACKGROUND: To systematically assess the quality of reports of clinical trials of stem cell for heart diseases published in Chinese. METHODS: The quality of reports was assessed according to the CONSORT statement and the Jadad score. The association between the CONSORT scores and the reported therapeutic effects was evaluated. RESULTS: A total of 36 randomized clinical trials were identified, and 1552 patients were included. The mean CONSORT score was 7.06 (SD = 2.99). The proportion of reports with a Jadad score of 3 was 8.33%. The improvement of left ventricular function, myocardial perfusion area, left ventricular diastolic diameter, and cardiac output decreased with the increase in the CONSORT score. CONCLUSIONS: The percentages of high-quality reports published in Chinese on stem cell therapy for heart diseases are low. Although stem cell transplantation seems promising for heart diseases, high-quality studies are needed to verify the conclusions..


Asunto(s)
Cardiopatías , Informe de Investigación , China , Cardiopatías/cirugía , Humanos , Trasplante de Células Madre
11.
Zool Res ; 41(1): 78-83, 2020 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-31746565

RESUMEN

Individual dispersal trends, unquestionably important for species ecology and evolution, are affected by multiple factors. Understanding the factors that influence female dispersal strategies offers important insight into primate dispersal mechanisms and female choice. To investigate the proximate causes of dispersal in female Yunnan snub-nosed monkeys (Rhinopithecus bieti), we observed and analyzed nine years of detailed dispersal and demographic data from a population of R. bieti in Xiangguqing, Baimaxueshan Nature Reserve, Yunnan Province, China. Results showed that females who lived long-term in a one-male unit (OMU), without giving birth and with few or no relatives, were more likely to leave that OMU. In addition, an OMU led by an outgroup male and containing more female relatives was significantly more likely to be chosen for immigration. Conversely, greater male age, longer male tenure, and more potentially fertile females discouraged immigration into an OMU. These results suggest that reproduction, male quality, and kin cooperation play the largest roles in female Yunnan snub-nosed monkey dispersal.


Asunto(s)
Distribución Animal , Conducta Animal , Presbytini/fisiología , Conducta Social , Envejecimiento , Animales , Femenino , Masculino
12.
Drug Des Devel Ther ; 13: 3625-3634, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31695330

RESUMEN

PURPOSE: The aim of this study is to assess the bioequivalence of a new generic formulation and the branded formulation of levocetirizine dihydrochloride in healthy Chinese volunteers under fasting and fed conditions, and food-intake effect on the pharmacokinetic properties is also evaluated. PATIENTS AND METHODS: Volunteers were randomly allocated into two groups to receive a single oral dose of generic formulation and branded formulation under fasting or fed conditions, respectively. Blood samples were collected at designated time points. Plasma concentrations of levocetirizine were determined by UFLC-MS/MS. Safety evaluations were carried out through the study. The main pharmacokinetic parameters of the two formulations of levocetirizine were calculated using non-compartmental analysis incorporated in WinNonlin® 7.0 software. RESULTS: Forty-nine volunteers were enrolled; 46 completed the studies. Under fasting and fed conditions, the 90% confidence intervals for the geometric mean of generic/branded ratios were in the range of 94.75-107.24% and 99.98-114.69% for the maximum observed concentration, and 97.13-102.50% and 98.36-103.98% for the area under the concentration-time curve. As a result of food intake before administration, the reduced rate and extent of absorption of levocetirizine were observed. Both formulations were generally well tolerated, with no serious adverse reactions reported. CONCLUSION: The two formulations demonstrated essentially identical pharmacokinetic profiles and were all well within the FDA/CFDA bioequivalence standards. Meanwhile, food intake can delay the absorption rate and reduced the bioavailability of levocetirizine in healthy Chinese volunteers.


Asunto(s)
Cetirizina/administración & dosificación , Medicamentos Genéricos/administración & dosificación , Interacciones Alimento-Droga , Antagonistas de los Receptores Histamínicos H1 no Sedantes/administración & dosificación , Administración Oral , Adolescente , Adulto , Área Bajo la Curva , Disponibilidad Biológica , Cetirizina/efectos adversos , Cetirizina/farmacocinética , Cromatografía Líquida de Alta Presión , Estudios Cruzados , Medicamentos Genéricos/efectos adversos , Medicamentos Genéricos/farmacocinética , Femenino , Antagonistas de los Receptores Histamínicos H1 no Sedantes/efectos adversos , Antagonistas de los Receptores Histamínicos H1 no Sedantes/farmacocinética , Humanos , Masculino , Proyectos Piloto , Espectrometría de Masas en Tándem , Equivalencia Terapéutica , Adulto Joven
13.
Taiwan J Obstet Gynecol ; 58(6): 833-839, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31759537

RESUMEN

OBJECTIVE: Substantial previous studies have almost reached an agreement on the gender effect on maternal serum human chorionic gonadotropin (MsHCG) in and after the late first trimester of pregnancy. However, there is little knowledge of the sex-related difference in MsHCG level at the preliminary stage of pregnancy. The purpose of this study is to reveal this difference in women after fresh or frozen single blastocyst transfer (SBT). MATERIALS AND METHODS: A total of 252 fresh SBT cycles and 1486 frozen-thawed SBT cycles collected between June 1, 2014 and May 30, 2017 were retrospectively analyzed in our center. Patients with MsHCG level ≥5 IU/L on day 11 after transfer, achieving a singleton intrauterine pregnancy and subsequent live birth were included. We compared MsHCG levels between women gave birth to a male neonate and those gave birth to a female one in fresh or frozen SBT cycles, respectively. RESULTS: A total of 136 neonates including 57 females and 79 males were born following fresh SBT. The male-female ratio was 1.39:1. The average MsHCG level of male fetuses was higher than that of female fetuses on day 11 after transfer (549.82 ± 253.24 IU/L versus 439.03 ± 198.41 IU/L, P < 0.05). Correspondingly, a total of 431 infants was born after frozen SBT, containing 188 females and 243 males. The male-female ratio was 1.29:1. Initial MsHCG level remained higher in women with a male neonate than the counterparts with a female neonate (894.43 ± 622.17 IU/L versus 758.05 ± 624.33 IU/L, P < 0.05). It was also found the pregnant women following frozen-thawed SBT exhibited higher initial MsHCG level than those following fresh SBT in whether male-bearing or female-bearing gestations. CONCLUSIONS: MsHCG levels are higher in pregnant women with a male fetus than those with a female one on day 11 after fresh or frozen SBT. A sex-specific response to the stress in the process of in vitro embryo culture was suggested.


Asunto(s)
Gonadotropina Coriónica/sangre , Criopreservación/métodos , Fertilización In Vitro/métodos , Primer Trimestre del Embarazo/sangre , Transferencia de un Solo Embrión/métodos , Adulto , Biomarcadores/sangre , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Masculino , Embarazo , Índice de Embarazo/tendencias , Estudios Retrospectivos , Factores Sexuales
14.
Insects ; 10(6)2019 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-31167426

RESUMEN

Seasonal weather systems that establish prevailing winds and seasonal rainfall on a large scale largely determine insect migration patterns, especially for micro-insects with completely windborne migration. Recent studies indicated that the summer migration of the brown planthopper (BPH, Nilaparvata lugens) in eastern China is related to the strength and position of the Western Pacific Subtropical High-Pressure (WPSH) system and its associated wind and rainfall patterns. Compared with the BPH, the white-backed planthopper (WBPH, Sogatella furcifera) has a similar diet, analogous body size, and strong long-distance migration ability. Thus, the migration pattern for the WBPH can be speculated to be similar to that of the BPH. However, the migration pattern of the WBPH and how this pattern relates to climatic conditions have scarcely been described. Based on almost three decades of data (1977-2003), it was suggested that the WBPH in southern China (south of approximately 27° N) migrates into the middle and lower reaches of the Yangtze River after the abrupt movements of the WPSH in mid-June, similar to the BPH. By contrast, the emigration of the WBPH in southern China begins in late May. Further analysis indicated that the migration of the WBPH in late May and early June was short or unsuccessful due to heavy precipitation during the preflood season in southern China from late May to middle June. The results herein demonstrate the differences in migration patterns between two rice planthoppers in the eastern Asia migration arena. We also provide new information that could assist with forecasting outbreaks and implementing control measures against these migratory pests.

15.
J Pest Sci (2004) ; 92(2): 417-428, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30956648

RESUMEN

Rice planthoppers and associated virus diseases have become the most important pests threatening food security in China and other Asian countries, incurring costs of hundreds of millions of US dollars annually in rice losses, and in expensive, environmentally harmful, and often futile control efforts. The most economically damaging species, the brown planthopper, Nilaparvata lugens (Hemiptera: Delphacidae), cannot overwinter in temperate East Asia, and infestations there are initiated by several waves of windborne spring or summer migrants originating from tropical areas in Indochina. The interaction of these waves of migrants and synoptic weather patterns, driven by the semi-permanent western Pacific subtropical high-pressure (WPSH) system, is of critical importance in forecasting the timing and intensity of immigration events and determining the seriousness of subsequent planthopper build-up in the rice crop. We analysed a 26-year data set from a standardised light trap network in Southern China, showing that planthopper aerial transport and concentration processes are associated with the characteristics (strength and position) of the WPSH in the year concerned. Then, using N. lugens abundance in source areas and indices of WPSH intensity or related sea surface temperature anomalies, we developed a model to predict planthopper numbers immigrating into the key rice-growing area of the Lower Yangtze Valley. We also demonstrate that these WPSH-related climatic indices combined with early-season planthopper catches can be used to forecast, several months in advance, the severity of that season's N. lugens infestations (the correlation between model predictions and outcomes was 0.59), thus allowing time for effective control measures to be implemented.

16.
Anticancer Drugs ; 30(3): 302-307, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30520775

RESUMEN

The aim of this retrospective analysis was to evaluate the efficacy and toxicity of combination chemotherapy with paclitaxel, 5-fluorouracil, and leucovorin (TFL) as first-line treatment in patients with advanced gastric cancer (AGC). One hundred and thirteen patients were enrolled in the study who were confirmed to have AGC by histopathology. These patients were treated with TFL: paclitaxel at a dose of 135 mg/m as a 3-h intravenous infusion on day 1, LV 400 mg/m as an intravenous infusion over 2 h on day 1, followed by 5-fluorouracil 2400 mg/m as an infusion over a 46-h period on 3 consecutive days. Cycles were repeated every 2 weeks. A total of 113 patients were assessed for their response to therapy. A total of three patients achieved complete responses and 46 patients achieved partial responses, yielding an overall objective response rate of 43.4% [95% confidence interval (CI): 34.3-52.5%]. Fifty-four cases of stable disease and 10 cases of progressive disease were observed in the remaining patients. The median time to progression and overall survival were 5.2 months (95% CI: 4.7-5.8 months) and 14.1 months (95% CI: 12.5-15.8 months), respectively. Toxicities were tolerable and moderate. The most common grade 3-4 toxicities included leukopenia (16.8%), neutropenia (17.7%), anemia (8.0%), thrombocytopenia (5.3%), and fatigue (6.2%). Combination chemotherapy with TFL offers an active and safe therapeutic approach for patients with AGC.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Adenocarcinoma/secundario , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Leucovorina/administración & dosificación , Metástasis Linfática , Masculino , Persona de Mediana Edad , Paclitaxel/administración & dosificación , Pronóstico , Estudios Retrospectivos , Neoplasias Gástricas/patología , Tasa de Supervivencia , Adulto Joven
17.
Zhonghua Nan Ke Xue ; 25(2): 124-128, 2019 Feb.
Artículo en Chino | MEDLINE | ID: mdl-32216197

RESUMEN

OBJECTIVE: To compare the results obtained from the computer-aided sperm analysis (CASA) systems of the two fully-automated commercial sperm quality analyzers, Hamilton-Thorn IVOS Ⅱ (IVOS Ⅱ) and Spanish Sperm Class Analyzer (SCA). METHODS: A total of 99 semen samples were collected in the Center of Reproduction of Shenzhen Zhongshan Urology Hospital from September 2018 to October 2018 and, according to the sperm concentration, divided into groups A (<15 ×106/ml), B (15-50 ×106/ml) and C (>50 ×106/ml). IVOS Ⅱ, SCA and manual microscopy were used for the examination of each sample, followed by comparison of the sperm concentration, sperm motility and percentage of progressively motile sperm (PMS) obtained from IVOS Ⅱ and SCA. RESULTS: The sperm concentrations derived from IVOS Ⅱ and SCA were significantly higher than that from manual microscopy in group A (ï¼»10.24 ± 4.60ï¼½ and ï¼»10.20 ± 5.11ï¼½ vs ï¼»8.45 ± 4.15ï¼½ ×106/ml, P < 0.05), but showed no statistically significant difference in group B (ï¼»30.95 ± 11.84ï¼½ and ï¼»31.81 ± 12.90ï¼½ vs ï¼»29.14 ± 10.65ï¼½ ×106/ml, P > 0.05) or C (ï¼»102.14 ± 45.97ï¼½ and ï¼»109.48 ± 46.32ï¼½ vs ï¼»104.74 ± 41.87ï¼½ ×106/ml, P > 0.05). Significant differences were not observed between IVOS Ⅱ and SCA in the percentage of PMS (ï¼»24.21 ± 14.62ï¼½% vs ï¼»23.92 ± 15.42ï¼½%, P > 0.05) or sperm motility (ï¼»37.48 ± 19.34ï¼½% vs ï¼»37.69 ± 16.61ï¼½%, P > 0.05) in group B, nor in group C (PMS: ï¼»30.80 ± 12.06ï¼½% vs ï¼»32.98 ± 16.10ï¼½%, P > 0.05; sperm motility: ï¼»44.50 ± 15.62ï¼½% vs ï¼»47.26 ± 17.46ï¼½%, P > 0.05). Both the percentage of PMS and sperm motility obtained from IVOS Ⅱ were remarkably lower than those derived from SCA in group A (PMS: ï¼»18.54 ± 12.96ï¼½% vs ï¼»22.90 ± 12.88ï¼½%, P < 0.05; sperm motility: ï¼»26.97 ± 14.05ï¼½% vs ï¼»34.90 ± 15.18ï¼½%, P < 0.05). IVOS Ⅱ and SCA both showed a high repeatability (CV <15%), and the former exhibited an even higher one than the latter, in detection of sperm concentration, sperm motility and the percentage of PMS. CONCLUSIONS: IVOS Ⅱ and SCA both had a good consistency in the results of sperm concentration, motility and progressive motility, but showed a poor comparability with low-concentration semen samples.


Asunto(s)
Análisis de Semen/instrumentación , Motilidad Espermática , Diagnóstico por Computador , Humanos , Masculino , Recuento de Espermatozoides , Espermatozoides
18.
Int J Biometeorol ; 62(8): 1389-1406, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29713863

RESUMEN

Mass landings of migrating white-backed planthopper, Sogatella furcifera (Horváth), can lead to severe outbreaks that cause heavy losses for rice production in East Asia. South-central China is the main infestation area on the annual migration loop of S. furcifera between the northern Indo-China Peninsula and mainland China; however, rice planthopper species are not able to survive in this region over winter. In this study, a trajectory analysis of movements from population source areas and a spatiotemporal dynamic analysis of mesoscale and synoptic weather conditions from 7 to 10 May 2012 were conducted using the weather research and forecasting (WRF) model to identify source areas of immigrants and determine how weather and topographic terrain influence insect landing. A sensitivity experiment was conducted with reduced topography using the WRF model to explain the associations among rainfall, topography, and light-trap catches of S. furcifera. The trajectory modeling results suggest that the source areas of S. furcifera immigrants into south-central China from 8 to 10 May were mainly southern Guangxi, northern Vietnam, and north-central Vietnam. The appearance of enormous catches of immigrant S. furcifera coincided with a period of rainstorms. The formation of transporting southerly winds was strongly associated with the topographic terrain. Additionally, the rainfall distribution and intensity over south-central China significantly decreased when topography was reduced in the model and were directly affected by wind circulation, which was associated with mountainous terrain that caused strong convection. This study indicates that migrating populations of S. furcifera were carried by the southwesterly low-level jets and that topographically induced convergent winds, precipitation, low temperatures, and wind shear acted as key factors that led to massive landings.


Asunto(s)
Distribución Animal , Hemípteros , Animales , China , Oryza , Lluvia , Vietnam , Viento
19.
Eur J Radiol ; 103: 118-123, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29803376

RESUMEN

PURPOSE: To clarify whether the quantitative parameters of contrast-enhanced ultrasound (CEUS) can be used to predict pathological complete response (pCR) in patients with locally advanced breast cancer receiving neoadjuvant chemotherapy (NAC). MATERIAL AND METHODS: Fifty-one patients with histologically proved locally advanced breast cancer scheduled for NAC were enrolled. The quantitative data for CEUS and the tumor diameter were collected at baseline and before surgery, and compared with the pathological response. Multiple logistic regression analysis was performed to examine quantitative parameters at CEUS and the tumor diameter to predict the pCR, and receiver operating characteristic (ROC) curve analysis was used as a summary statistic. RESULTS: Multiple logistic regression analysis revealed that PEAK (the maximum intensity of the time-intensity curve during bolus transit), PEAK%, TTP% (time to peak), and diameter% were significant independent predictors of pCR, and the area under the ROC curve was 0.932(Az1), and the sensitivity and specificity to predict pCR were 93.7% and 80.0%. The area under the ROC curve for the quantitative parameters was 0.927(Az2), and the sensitivity and specificity to predict pCR were 81.2% and 94.3%. For diameter%, the area under the ROC curve was 0.786 (Az3), and the sensitivity and specificity to predict pCR were 93.8% and 54.3%. The values of Az1 and Az2 were significantly higher than that of Az3 (P = 0.027 and P = 0.034, respectively). However, there was no significant difference between the values of Az1 and Az2 (P = 0.825). CONCLUSION: Quantitative analysis of tumor blood perfusion with CEUS is superior to diameter% to predict pCR, and can be used as a functional technique to evaluate tumor response to NAC.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Medios de Contraste , Aumento de la Imagen/métodos , Terapia Neoadyuvante/métodos , Ultrasonografía Mamaria/métodos , Adulto , Mama/diagnóstico por imagen , Mama/patología , Femenino , Humanos , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos , Sensibilidad y Especificidad , Resultado del Tratamiento
20.
J Ultrasound Med ; 37(10): 2405-2412, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29656388

RESUMEN

OBJECTIVES: The purpose of this study was to evaluate the application of a new elastographic technique, acoustic radiation force impulse (ARFI) imaging, and its diagnostic performance for characterizing breast lesions. METHODS: One hundred consecutive female patients with 126 breast lesions were enrolled in our study. After routine breast ultrasound examinations, the patients underwent ARFI elasticity imaging. Virtual Touch tissue imaging (VTI) and Virtual Touch tissue quantification (Siemens Medical Solutions, Mountain View, CA) were used to qualitatively and quantitatively analyze the elasticity and hardness of tumors. A receiver operating characteristic curve analysis was performed to evaluate the diagnostic performance of ARFI for discrimination between benign and malignant breast lesions. RESULTS: Pathologic analysis revealed 40 lesions in the malignant group and 86 lesions in the benign group. Different VTI patterns were observed in benign and malignant breast lesions. Eighty lesions (93.0%) of benign group had pattern 1, 2, or 3, whereas all pattern 4b lesions (n = 20 [50.0%]) were malignant. Regarding the quantitative analysis, the mean VTI-to-B-mode area ratio, internal shear wave velocity, and marginal shear wave velocity of benign lesions were statistically significantly lower than those of malignant lesions (all P < .001). The cutoff point for a scoring system constructed to evaluate the diagnostic performance of ARFI was estimated to be between 3 and 4 points for malignancy, with sensitivity of 77.5%, specificity of 96.5%, accuracy of 90.5%, and an area under the curve of 0.933. CONCLUSIONS: The application of ARFI technology has shown promising results by noninvasively providing substantial complementary information and could potentially serve as an effective diagnostic tool for differentiation between benign and malignant breast lesions.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Diagnóstico por Imagen de Elasticidad/métodos , Ultrasonografía Mamaria/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Mama/diagnóstico por imagen , Diagnóstico Diferencial , Estudios de Evaluación como Asunto , Femenino , Humanos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Adulto Joven
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