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1.
Appl Opt ; 63(11): 2837-2842, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856379

RESUMEN

An X-ray monocapillary with an inner multilayer can be a promising optical device to obtain focused monochromatic X-rays. A focused beam is acquired via controlling the shape of the monocapillary meanwhile monochromatic X-rays are screened out by the inside multilayer. For hard X-rays such as C u-k α line 8.04 keV and M o-k α line 17.44 keV, A l 2 O 3/H f O 2 is an effective material pair for the X-ray multilayer that can reflect the X-rays at an acceptable efficiency. In this work, four tapered-monocapillaries with inner A l 2 O 3/H f O 2 multilayers are designed to focus and monochromatize X-rays (8.04 keV and17.44 keV, respectively) from the point source and collimated beam. The theoretical transmission performance, including the beam size, reflectivity, and monochromaticity of the device, is also calculated. The results show that the ideal optics can focus desired X-rays with efficiency of about 60%. It provides a reference for fabricating this optics in the future, especially via the atomic layer deposition (ALD) technique, which represents great potential to coat uniform film on a curved surface.

2.
World J Surg Oncol ; 19(1): 73, 2021 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-33714262

RESUMEN

BACKGROUND: The incidence of adenocarcinoma of the esophagogastric junction (AEG) is rising every year; however, the mode of operation for Siewert II AEG is still controversial. Accumulating evidence has shown that transabdominal surgery is better than transthoracic surgery for Siewert II AEG with esophageal invasion < 3 cm. In patients with obesity, a large tumor size, and high transection of the esophagus, the transabdominal esophageal hiatus approach for lower mediastinal lymph node dissection and posterior mediastinal anastomosis is difficult. Thus, total laparoscopic radical resection of Siewert II AEG is carried out through the left diaphragm and left chest auxiliary hole for the optimal surgical field of vision and space. In this prospective study, we assessed the feasibility of carrying out the procedure abdominally through the left diaphragm and auxiliary hole. METHODS: Ten patients with Siewert II AEG were recruited between April and June 2019. Siewert II AEG was treated by total laparoscopy through the left diaphragm and left chest auxiliary hole. Clinicopathological features, surgical data, and adverse events were collected and analyzed in this prospective study. RESULTS: The average duration of the operation was 348 ± 37.52 min, lower mediastinal dissection took 20.6 min, the OrVil anastomosis time was 29.8 min, the time necessary to suture the seromuscular layer through the left thoracic auxiliary hole was 11 min, the safety margin was 3.2 cm, and the total number of lymph nodes dissected was 40.6. The number of lower mediastinal lymph nodes dissected was 6.2. The rate of lymph node metastasis in the N110 group was 9 ± 12.45%, and the average intraoperative blood loss was 170 ± 57.47 mL. No anastomotic leakage or anastomotic stricture occurred after the operation. The time of intestinal function recovery was 2 days, and the first time of enteral nutrition through a jejunal nutrition tube was 2.4 days. No tumor recurrence was found in 10 patients at 1 year postoperatively. CONCLUSION: Total laparoscopic radical resection through the left diaphragm and left thoracic auxiliary hole for Siewert II AEG patients is feasible and safe. Thus, it may be a good surgical alternative for patients with esophageal tumors invading less than 3 cm. TRIAL REGISTRATION: ChiCTR, ChiCTR2000034286. Registered 8 July 2020, http://www.chictr.org.cn/showproj.aspx?proj=55866 .


Asunto(s)
Adenocarcinoma , Neoplasias Esofágicas , Laparoscopía , Neoplasias Gástricas , Adenocarcinoma/cirugía , Diafragma/cirugía , Neoplasias Esofágicas/cirugía , Unión Esofagogástrica/cirugía , Estudios de Factibilidad , Gastrectomía , Humanos , Escisión del Ganglio Linfático , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos , Neoplasias Gástricas/cirugía
3.
J Surg Res ; 246: 442-449, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31635836

RESUMEN

BACKGROUND: MicroRNA (miRNA)-382-5p functions as an oncogenic miRNA in breast cancer. MXD1 was demonstrated to be one of its direct targets. However, the involvement of miRNA-382-5p/MXD1 axis in breast cancer remains unknown. The aim of this study was to investigate the expression pattern, clinical significance, and potential functions of miRNA-382-5p/MXD1 axis in breast cancer. MATERIALS AND METHODS: Quantitative polymerase chain reaction was performed to detect the expression levels of miRNA-382-5p and MXD1 messenger RNA (mRNA) in 96 pairs of breast cancer and matched noncancerous breast tissue samples from the same patients. Relationships between miRNA-382 expression, MXD1 expression, and combined miRNA-382-5p and MXD1 expression, and various clinicopathological characteristics of breast cancer were statistically evaluated, and their roles in breast cancer cell proliferation and invasion were also examined. RESULTS: Compared with noncancerous breast tissues, miRNA-382-5p expression was upregulated but MXD1 mRNA expression was downregulated in breast cancer tissues (both P < 0.01). High miRNA-382 expression, MXD1 expression, and combined miRNA-382-5p and low MXD1 expression were significantly associated with advanced tumor stage and the presence of lymph node metastasis (all P < 0.05). Overexpression of miRNA-382-5p dramatically reduced MXD1 mRNA and protein expression levels in breast cancer cells. miRNA-382-5p upregulation markedly enhanced breast cancer cell proliferation and invasion, while its downregulation inhibited these malignant phenotypes of breast cancer cells in vitro. Notably, overexpressed MXD1 reversed the effects of upregulated miRNA-382-5p on cell proliferation and invasion in vitro. CONCLUSIONS: The dysregulation of miRNA-382-5p-MXD1 axis may be involved in the development and aggressive progression of breast cancer. miRNA-382-5p may target MXD1, leading to cell invasion and proliferation in breast cancer cells in vitro, implying its potentials as a therapeutic target for this type of cancer.


Asunto(s)
Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Neoplasias de la Mama/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/metabolismo , Proteínas Represoras/genética , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Mama/patología , Neoplasias de la Mama/patología , Proliferación Celular/genética , Progresión de la Enfermedad , Regulación hacia Abajo , Femenino , Humanos , Células MCF-7 , Persona de Mediana Edad , Invasividad Neoplásica/genética , ARN Mensajero/metabolismo , Proteínas Represoras/metabolismo
4.
Environ Sci Technol ; 46(7): 3891-7, 2012 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-22376064

RESUMEN

Suspension of the pristine and COOH-substituted multi-walled carbon nanotubes (P- and C-MWCNTs) with different outer diameters (ODs) by humic acids (HAs) from a peat soil was examined. Under shaking condition, MWCNTs were not suspended within 5 d. Without HAs, C-MWCNTs were slightly suspended by sonication within 16 h, but no suspension was observed for the pristine ones (P-MWCNTs). HAs greatly enhanced suspension of both P- and C-MWCNTs. The suspension enhancement was attributed to HA sorption, which increased electrostatic repulsion and steric hindrance between individual MWCNTs. Introduction of O-containing hydrophilic moieties to MWCNTs via HA sorption enhanced the interactions of their surfaces with water through H-bonding. Suspending capability of various MWCNTs on suspended mass concentration basis by four HAs showed inconsistent orders with the increasing or decreasing trend of their ODs. However, the suspended surface area concentrations of both P- and C-MWCNTs by individual HAs consistently followed an order of P8 > P30 > P50, and C8 > C30 > C50 (P and C, respectively, refer to P- and C-MWCNTs, and the numbers represent their ODs). These data implied that MWCNTs with smaller OD could be more strongly suspended by a given HA relative to those with larger OD under sonication condition.


Asunto(s)
Sustancias Húmicas/análisis , Nanotubos de Carbono/química , Suelo/química , Cinética , Oxígeno/química , Porosidad , Electricidad Estática , Propiedades de Superficie , Suspensiones
5.
Biodivers Data J ; 10: e91132, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36761514

RESUMEN

Background Artificial forest can have great potential in serving as habitat to wildlife, depending on different management methods. As the state-owned forest farms now play a new role in ecological conservation in China, the biological richness of this kind of land-use type is understudied. Once owned by a mining company, a largest state-owned forest farm, Jingxi Forest Farm, has been reformed to be a state-owned forest farm with the purpose of conservation since 2017. Although this 116.4 km2 forest farm holds a near-healthy montaine ecosystem very representative in North China, a large proportion of artificial coniferous forest in the forest farm has been proven to hold less biodiversity than natural vegetation. This situation, however, provides a great opportunity for ecological restoration and biodiversity conservation. Therefore, from November 2019 to December 2020, we conducted a set of biodiversity surveys, whose results will serve as a baseline for further restoration and conservation. New information Here, we report the result of a multi-taxa fauna diversity survey conducted in Jingxi Forest Farm mainly in year 2020 with explicit spatial information. It is the first survey of its kind conducted in this area, revealing a total of 19 species of mammals, 86 birds, four reptiles, two amphibians and one fish species, as well as 101 species of insects. Four species of mammals are identified as data-poor species as they have less than 100 occurrence records with coordination in the GBIF database. One species of insect, representing one new provincial record genus of Beijing, is reported.

6.
Gland Surg ; 10(1): 378-385, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33633995

RESUMEN

Although ectopic thyroid can be found in thoracic locations, the discovery of abdominal ectopic thyroid is often an accidental event. Moreover, abdominal ectopic thyroid is easily misdiagnosed due to the rarity of these cases and the difficulties in the preoperative diagnosis process. Thus, we aimed to assess the prevalence and features of abdominal ectopic thyroid and to highlight the current knowledge about the clinical characteristics and management of this condition by analyzing a case report of abdominal ectopic thyroid and reviewing the literature. A 70-year-old woman with a 3-year history of gradually increasing abdominal distension in the right lower quadrant of the abdomen was admitted to the hospital. Contrast-enhanced computed tomography (CT) of the abdomen revealed a retroperitoneal mass. The patient underwent Da Vinci robotic surgery, and the retroperitoneal mass was completely resected. Subsequently, the pathologic diagnosis of the mass was ET. The patient had no discomfort or symptoms when she was discharged from the hospital and at the postoperative 1, 3, 6, 9 and 12 months follow-up. The summary of literature review suggested that abdominal ectopic thyroid is still rare although there are some reports. Nonetheless, the cause of abdominal ectopic thyroid is unclear, and abdominal ectopic thyroid has the following characteristics: more common in women than in men, asymptomatic in the majority of the cases, difficult to diagnose, and found by excluding metastasis. Most ectopic thyroid is treated with surgery, and minimally invasive techniques have been increasingly performed. This is the first report on Da Vinci robotic resection for large rare retroperitoneal ET, and this case highlights that ET should be considered when patients present with similar imaging findings in the abdomen.

7.
Oncol Lett ; 20(2): 1945-1951, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32724439

RESUMEN

Expression level of Fibulin-2 gene in breast cancer cells was evaluated to explore the impact of Fibulin-2 gene on the proliferation, migration and invasion of breast cancer cells. MDA-MB-231, BT483, MCF-7 and SK-BR-3 breast cancer cells were cultured in vitro. Then, expression of Fibulin-2 in cells was upregulated and downregulated using ribonucleic acid interference (RNAi) and lentiviral transfection techniques, respectively. Thereafter, expression levels of Fibulin-2 messenger RNA (mRNA) and protein were measured via quantitative real-time reverse transcription-polymerase chain reaction and western blotting, respectively. Cell Counting Kit-8 assay was applied to detect the proliferation ability, and wound healing assay was performed to determine the effect of transfection on the metastatic capacity of cells. The influence of transfection on the invasive ability of breast cancer cells was detected through Transwell chamber assay. MDA-MB-231 and MCF-7 cells did not express Fibulin-2, while BT483 and SK-BR-3 cells expressed Fibulin-2. Expression of Fibulin-2 mRNA and protein in SK-BR-3 Fibulin-2 siRNA group was significantly lower than that in SK-BR-3 NC siRNA group 48 h after transfection (P<0.01), while the expression of Fibulin-2 mRNA and protein in MDA-MB-231 Fibulin-2 lentiviral transfection (LAP) group was significantly higher than that in MDA-MB-231 NC LAP group. Compared with the MDA-MB-231 NC LAP group, the cell proliferation, migration and invasion ability of MDA-MB-231 Fibulin-2 LAP group were weakened. The tumor volume and weight of the MDA-MB-231 Fibulin-2 LAP group were significantly lower than those of the MDA-MB-231 NC LAP group. Low expression of Fibulin-2 is able to promote proliferation, migration and invasion of breast cancer cells, and can reduce the rate of tumor growth in nude mice. Therefore, Fibulin-2 may be a potential therapeutic target and an indicator of prognosis for breast cancer.

8.
Open Life Sci ; 13: 11-21, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33817062

RESUMEN

Polar microbial derived antibiotics have potential as alternatives to traditional antibiotics in treating fish against pathogenic bacteria. In this paper, 23 strains of polar fungi were fermented to detect bacteriostatic products on three aquatic pathogenic bacteria, subsequently the active fungus was identified. It was indicated that secondary metabolites of 23 strains weredistinct; of these, the extract of strain B-7 (belonging to Bjerkandera according to molecular identification) demonstrated a strong antibacterial activity to Streptococcus agalactiae, Vibrio anguillarum and Aeromonas hydrophila ATCC7966 by Kirby-Bauerpaper strip method. During one fermentation cycle, the pH curve of the fermentation liquor became lowest (4.0) on the 4th day and rose back to 7.6 finally after 5 days, The residual sugar curve was decreased before stablising on the 6th day. It is presumed that a large amount of alkaline secondary metabolites might have been produced during fermentation. This study focuses on antagonism between aquatic pathogenic bacteria and fermentation metabolites from Antarctic fungi for the first time, which may provide data on research of antibiotics against aquatic pathogenic bacteria.

9.
BMC Cancer ; 6: 298, 2006 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-17192200

RESUMEN

BACKGROUND: Overexpression of Fra-1 in fibroblasts causes anchorage-independent cell growth and oncogenic transformation. A high level of Fra-1 expression is found in various tumors and tumorigenic cell lines, suggesting that Fra-1 may be involved in malignant progression. This study aimed to investigate the significance of Fra-1 expression in breast carcinogenesis. METHODS: The expression of Fra-1 was investigated by immunohistochemistry in neoplastic breast diseases ranging from benign fibroadenoma to very aggressive undifferentiated carcinoma. The correlations of Fra-1 expression with other indicators of breast carcinoma prognosis (ER, PR and ErbB2 receptors) were analyzed. RESULTS: All neoplastic breast tissues, either benign or malignant breast tissues, were nuclear immunoreactive for Fra-1-recognizing antibody. The pattern of Fra-1 expression by benign neoplastic cells was predominantly nuclear. However, the nuclear/cytoplasmic concomitant immunoreactivity was observed in all types of breast carcinomas. A clear shift in Fra-1 immunoreactivity, from an exclusively nuclear to a simultaneous nuclear and cytoplasmic localization was noticed in ~90% of breast carcinomas. CONCLUSION: The overall expression, pattern and intensity of Fra-1 proteins were correlated with breast oncogenesis. Overexpression of Fra-1, leading to a persistent high cytoplasmic accumulation, may play a role in the process of breast carcinogenesis.


Asunto(s)
Neoplasias de la Mama/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Proteínas Proto-Oncogénicas c-fos/genética , Proteínas Proto-Oncogénicas c-fos/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Femenino , Humanos , Inmunohistoquímica , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/análisis , Receptores de Progesterona/metabolismo
10.
Int J Nanomedicine ; 6: 3057-64, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22162662

RESUMEN

Many studies in recent years have focused on surface engineering of implant materials in order to improve their biocompatibility and other performance. Porous tantalum implants have increasingly been used in implant surgeries, due to their biocompatibility, physical stability, and good mechanical strength. In this study we functionalized the porous tantalum implant for sustained drug delivery capability via electrostatic self-assembly of polyelectrolytes of hyaluronic acid, methylated collagen, and terpolymer on the surface of a porous tantalum implant. The anticancer drug doxorubicin was encapsulated into the multilayer copolymer membranes on the porous tantalum implants. Results showed the sustained released of doxorubicin from the functionalized porous tantalum implants for up to 1 month. The drug release solutions in 1 month all had inhibitory effects on the proliferation of chondrosarcoma cell line SW1353. These results suggest that this functionalized implant could be used in reconstructive surgery for the treatment of bone tumor as a local, sustained drug delivery system.


Asunto(s)
Antibióticos Antineoplásicos/química , Materiales Biocompatibles/química , Doxorrubicina/química , Implantes de Medicamentos/química , Membranas Artificiales , Polímeros/química , Tantalio/química , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/farmacocinética , Materiales Biocompatibles/administración & dosificación , Materiales Biocompatibles/farmacocinética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Condrosarcoma/tratamiento farmacológico , Condrosarcoma/metabolismo , Preparaciones de Acción Retardada , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacocinética , Implantes de Medicamentos/administración & dosificación , Implantes de Medicamentos/farmacocinética , Humanos , Ácido Hialurónico/administración & dosificación , Ácido Hialurónico/química , Ácido Hialurónico/farmacocinética , Porosidad , Electricidad Estática , Propiedades de Superficie
11.
Nanotechnology ; 17(6): 1778-85, 2006 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-26558593

RESUMEN

In this paper, a hybrid device based on a microcantilever interfaced with bacteriorhodopsin (bR) is constructed. The microcantilever, on which the highly oriented bR film is self-assembled, undergoes controllable and reversible bending when the light-driven proton pump protein, bR, on the microcantilever surface is activated by visible light. Several control experiments are carried out to preclude the influence of heat and photothermal effects. It is shown that the nanomechanical motion is induced by the resulting gradient of protons, which are transported from the KCl solution on the cytoplasmic side of the bR film towards the extracellular side of the bR film. Along with a simple physical interpretation, the microfabricated cantilever interfaced with the organized molecular film of bR can simulate the natural machinery in converting solar energy to mechanical energy.

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