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1.
Cancer Biother Radiopharm ; 34(7): 419-426, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31149837

RESUMO

Objective: To explore the association between the incidence of acute radiation gastritis attributed to postoperative intensity modulated irradiation therapy (IMRT) and the dose volume of intrathoracic stomach of patients with esophageal squamous cell carcinoma (ESCC) after radical esophagectomy. Methods: The authors retrospectively collected the data of 49 ESCC patients who participated in postoperative IMRT treatment after radical esophagectomy, and analyzed the incidence of acute radiation gastritis during the treatment. Results: Among all the 49 patients, acute grade ≥2 radiation gastritis was observed in 19 patients (39%). Receiver operating characteristic (ROC) curve analysis showed that the physical variables, such as stomach Dmax, Dmean, length of the whole stomach received 5-40 Gy (LSTT5-LSTT40), and V10-V50, were associated with acute radiation gastritis. Patients were grouped according to cutoff values in physical indicators obtained from the ROC curve. Other than V5, the incidence of acute grade ≥2 radiation gastritis was significantly higher in the group with indicators above cutoff values than that below cutoff values, and the between-group difference was statistically significant in terms of physical indicators. Multivariate analysis suggested that LSTT5 and V40 could be acted as indicators to predict the incidence of acute grade ≥2 radiation gastritis. Conclusions: In the postoperative IMRT treatment for ESCC patients, protection of intrathoracic stomach is strongly recommended. Dose-volume histogram is a preferable predictive indicator for the occurrence of acute radiation gastritis, especially for the stomach LSTT5 and V40. Nevertheless, a larger sample size is needed to provide insight into the relevant study.

2.
Inorg Chem ; 57(20): 13009-13019, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30281294

RESUMO

Clean fuels with extremely low sulfur content are highly desirable due to environmental concerns. Herein, three water-stable and eco-friendly metal-organic frameworks with tunable window diameters, denoted as MOF-808X, have been employed as PTA solid supports. An array of PTA@MOF-808X composites were facilely synthesized via the encapsulation strategy. With tunable window sizes and adjustable PTA loading amounts, the obtained PTA@MOF-808X composites were screened for catalytic oxidative desulfurization (ODS) with H2O2 serving as oxidant. The experiments found that 42%PTA@MOF-808A had the highest catalytic ODS activity and could completely remove dibenzothiophene (DBT) in a model fuel with an initial sulfur content of 1000 ppm within 30 min, which falls far below the acceptable limits for fuel standards (10 ppm). Further investigations revealed that this high catalytic activity could be attributed to the cooperative catalysis of metal clusters in the host framework and the guest PTA molecules. Moreover, 42%PTA@MOF-808A could be facilely recovered and reused for at least five runs without loss of catalytic activity. Having a combination of eco-sustainability, high stability, high catalytic activity, and good recyclability, 42%PTA@MOF-808A therefore represents a new benchmark material for catalytic ODS and provides a new perspective for ultradeep desulfurization.

3.
Inorg Chem ; 57(15): 9096-9104, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-29993241

RESUMO

Natural enzyme mimetics with high catalytic activity at nearly neutral pH values are highly desired for their applications in biological systems. Herein for the first time a stable MOF, namely MOF-808, has been shown to possess high intrinsic peroxidase-like catalytic activity under acidic, neutral, and alkaline conditions. As a novel peroxidase mimetic, MOF-808 can effectively catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine when H2O2 serves as oxidant, accompanied by a significant color variation in the solution. The catalytic activity and the color variation were greatly dependent on H2O2 concentration, and thus MOF-808 can be applied to the colorimetric sensing of H2O2. The H2O2 detection limit is 4.5 µM, and the linear range is 10 µM to 15 mM. In view of the significant inhibition effect produced by ascorbic acid, a facile and sensitive approach for colorimetric sensing of ascorbic acid was successfully established. The AA detection limit is 15 µM, and the linear range is 30-1030 µM. Further investigation found that the catalytic activity of MOF-808 could be mainly ascribed to the Zr-OH(OH2) groups. Such active Zr-OH(OH2) groups can be effectively shielded by gluconic acid, and subsequently the catalytic activity of MOF-808 was significantly suppressed. With these findings, a facile and selective colorimetric assay for glucose sensing has been successfully explored via combination of the glucose oxidation with the TMB oxidation. The glucose detection limit is 5.7 µM, and the linear range is 5.7-1700 µM. MOF-808 is one of the best colorimetric biosensors among the peroxidase mimics reported for H2O2, AA, and glucose detection.


Assuntos
Materiais Biomiméticos/química , Técnicas Biossensoriais/métodos , Colorimetria/métodos , Estruturas Metalorgânicas/química , Ácido Ascórbico/análise , Benzidinas/química , Materiais Biomiméticos/síntese química , Catálise , Glucose/análise , Peróxido de Hidrogênio/análise , Concentração de Íons de Hidrogênio , Cinética , Limite de Detecção , Estruturas Metalorgânicas/síntese química , Oxirredução , Peroxidases/química
4.
J Cancer Res Ther ; 12(1): 62-8, 2016 Jan-Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27072212

RESUMO

PURPOSE: This study investigates the failure pattern after chemoradiotherapy of patients with resectable esophageal squamous cell carcinoma (ESCC). MATERIALS AND METHODS: We retrospectively analyzed 92 patients with T1-2, N0-1, and M0 ESCC. These patients were inoperable because of poor performance, comorbidities, poor tumor region, or refusal of operation. RESULTS: Among the 92 patients, 29 cases displayed simple locoregional recurrence, 12 cases displayed simple distant metastasis, and 6 cases displayed distant metastasis with locoregional recurrence. Univariate analysis shows that the incidence of recurrence in the middle thoracic region was significantly higher than other regions (χ2 = 14.415, P = 0.001). For the 18 patients with distant metastasis, incidence of distant metastasis in the lower thoracic region was significantly higher than the other regions (= 39.359, P < 0.001). Among 35 cases with regional recurrence, 7 cases reached complete remission (14.6%) and 28 cases reached partial remission (PR; 63.6%) (χ2= 23.435, P < 0.001). Multivariate analysis shows that the patient age, tumor node metastasis (TNM) stage, and short-term efficacy were independent factors for locoregional recurrence. Patient age, TNM stage, X-ray length of the lesions, and short-term efficacy were the independent factors for distant metastases. CONCLUSION: The incidence of locoregional recurrence and distant metastasis in patients with upper thoracic esophageal cancer was lower than those who had middle thoracic and lower thoracic esophageal cancer. The incidence of locoregional recurrence and distant metastasis in patients who achieved complete response after treatment was low.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Quimiorradioterapia/efeitos adversos , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Recidiva Local de Neoplasia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Carcinoma de Células Escamosas do Esôfago , Esofagectomia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
5.
Biomed Res Int ; 2015: 569131, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26185758

RESUMO

Sugarcane mosaic disease is caused by the Sugarcane streak mosaic virus (SCSMV; genus Poacevirus, family Potyviridae) which is common in some Asian countries. Here, we established a protocol of a one-step real-time quantitative reverse transcription PCR (real-time qRT-PCR) using the TaqMan probe for the detection of SCSMV in sugarcane. Primers and probes were designed within the conserved region of the SCSMV coat protein (CP) gene sequences. Standard single-stranded RNA (ssRNA) generated by PCR-based gene transcripts of recombinant pGEM-CP plasmid in vitro and total RNA extracted from SCSMV-infected sugarcane were used as templates of qRT-PCR. We further performed a sensitivity assay to show that the detection limit of the assay was 100 copies of ssRNA and 2 pg of total RNA with good reproducibility. The values obtained were approximately 100-fold more sensitive than those of the conventional RT-PCR. A higher incidence (68.6%) of SCSMV infection was detected by qRT-PCR than that (48.6%) with conventional RT-PCR in samples showing mosaic symptoms. SCSMV-free samples were verified by infection with Sugarcane mosaic virus (SCMV) or Sorghum mosaic virus (SrMV) or a combination of both. The developed qRT-PCR assay may become an alternative molecular tool for an economical, rapid, and efficient detection and quantification of SCSMV.


Assuntos
Vírus do Mosaico/genética , Vírus do Mosaico/isolamento & purificação , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Saccharum/virologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Zhonghua Yi Xue Za Zhi ; 87(37): 2632-4, 2007 Oct 09.
Artigo em Chinês | MEDLINE | ID: mdl-18162152

RESUMO

OBJECTIVE: To investigate the morbidity and pathological features of incidental prostate cancer and their clinical significance. METHODS: 1483 prostate specimens obtained during operation, including transurethral resection of prostate (TURP) and total resection of the prostate, for the diagnoses of benign prostatic hypertrophy (BPH) or bladder cancer between January 1999 and August 2005 underwent pathological examination and 34beta12 and p63 immunohistochemical staining so as to detect incidental prostate cancer. The volume of incidental prostate cancer was calculated by the image analysis system. The clinical data were analyzed retrospectively. Comparison between the clinical and pathological feature of incidental prostate cancer was made. RESULTS: 53 cases of incidental prostate cancer, with the Gleason scores from 2 (1+1) to 9 (4+5) and the volumes from 0.18 to 1440.00 mm(3) were detected. The morbidity of incidental prostate cancer was 3.6%. The volume of 47 cases (88.7%) were less than 0.5 cm(3) as the threshold of insignificant cancer, and the volumes of 6 cases (11.3%) were more than 0.5 cm(3). All incidental prostate cancers of clinical significance were detected in the TURP samples. Among the incidental prostate cancers found in the TURP samples 20% were clinically significant cancers. The clinically significant incidental cancers were located in the central or transitional zone with the Gleason scores of 3 + 4 (2 cases), 4 + 2 (1 case), or 4 + 5 (3 cases). These clinically significant cancers were of diffuse distribution, and their preoperative clinical features were negative in palpation/image examination, elevation of serum PSA, and negative in puncture examination. CONCLUSION: Nowadays, the morbidity of incidental prostate cancer is lower than that of 1980s'. Among the incidental cancers 11.3% were of clinical significance. That the preoperative clinical examination cannot find these clinical significant cancers is partially caused by the pathological features of these tumors.


Assuntos
Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/patologia , Idoso , China/epidemiologia , Humanos , Imuno-Histoquímica , Incidência , Queratinas/análise , Masculino , Estadiamento de Neoplasias , Neoplasias da Próstata/metabolismo , Estudos Retrospectivos , Transativadores/análise , Fatores de Transcrição , Proteínas Supressoras de Tumor/análise
7.
Artigo em Inglês | MEDLINE | ID: mdl-17167196

RESUMO

Potassium pyroantimonate precipitation method was used for investigating calcium distribution and cell ultrastructure change during development of pistils of litchi male and female flower. The results showed that at the megasporocyte stage of female flowers, calcium precipitates was located mainly at cell wall and intercellular space of inner integument near the micropyle and style cells, and to a lesser extent in vacuoles. Vascular tissues also contained much calcium precipitates. In inner integument cells near the micropyle of male flowers, the vacuole contained most of the calcium precipitates. Calcium precipitates in style cell and vascular tissues of male flowers was sparse and seldom seen. After meiosis of megasporocyte, pistils of female flowers continued to grow and those of male flowers aborted. In female flowers, calcium precipitates concentration became lower and calcium precipitates was probably transported to the places for future pollen bourgeoning and fertilization. Cell wall calcium precipitates concentration increased in the inner integument cells near the micropyle. Calcium precipitates concentration increased from topper style cells to lower ones. In male flowers, inner integument cells near the micropyle underwent the programmed cell death (PCD): flow of calcium from vacuoles into nucleus might had triggered the PCD process. A continuous channel was formed between perinuclear space and cytoplasm membrane lumen, and calcium flowed freely between nuclear membrane and plasma membrane. At certain time and locations, calcium precipitates was newly appeared at some organelles like endoplasimic reticulum, mitochondria and peroxisomes. This calcium redistribution in cells might trigger and regulate the process of PCD. In male flowers, style cells containing no calcium precipitation soon began to degenerate.


Assuntos
Apoptose/fisiologia , Cálcio/metabolismo , Flores/metabolismo , Litchi/metabolismo , Flores/citologia , Flores/crescimento & desenvolvimento , Litchi/citologia , Litchi/ultraestrutura , Microscopia Eletrônica
8.
Artigo em Chinês | MEDLINE | ID: mdl-15840938

RESUMO

The ultrastructural changes of meristematic cell during the degeneration of gynoecium primordium leading to the formation of staminate flower of litchi were followed. Degradation of the cells and transport of the dissolved cytoplasmic components were well ordered. Configurations of rough endoplasmic reticulum (RER) changed significantly. ER played an important role in degenerative processes of gynoecium primordiuml cells. The degenerative processes started with the appearance of long RER cisternae throughout the cytoplasm. Some long RER cut or enclosed the cytoplasm. Some RER connected nucleus and mitochondria of adjacent cells, formed a ridge-like connection. Later the RER formed concentric patterns and then became irregular stacks. RER and golgiosome produced many vesicles, which were importance to protoplasmic degradation and intercellular transport of the cellular debris. The number of mitochondria increased up to the time when they began to degrade in batches. Peroxisomes appeared temporarily at the middle stage near the nucleus. The nucleolus disintegrated at the beginning of degeneration of nucleus. Then fragments of chromatin aggregated at the periphery of nuclear membrane and diffused outward. In some nuclei the perinuclear membrane became dilated and puffs were formed. As cell degeneration progressed, the protoplasm disintegrated and dissipated in an orderly fashion, i.e. ribosomes became disorganized first, followed by peroxisomes, ER, golgiosoms, mitochondria and nucleus. Eventually, gynoecium primordium cells digested all of the cytoplasm, leaving only cell wall with high electron density. Most of the products of degeneration of gynoecium primordium cells were removed through either symplastic or apoplastic pathways. Programmed cell death (PCD) may be involved in the degeneration of meristematic cells at the gynoecium primodium.


Assuntos
Flores/ultraestrutura , Litchi/ultraestrutura , Retículo Endoplasmático/ultraestrutura , Flores/citologia , Complexo de Golgi/ultraestrutura , Litchi/citologia , Meristema/citologia , Meristema/ultraestrutura , Microscopia Eletrônica de Transmissão , Mitocôndrias/ultraestrutura
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