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1.
Opt Lett ; 49(18): 5047-5050, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39270226

RESUMO

We report on the efficient generation of intense terahertz radiation from the organic crystal N-benzyl-2-methyl-4-nitroaniline pumped by chirped Ti:sapphire femtosecond laser pulses. The THz energy and spectrum as a function of the pump fluence and duration of the chirped laser pulses are studied systematically. For the appropriate positively chirped pump pulses, a significant boost in the THz generation efficiency by a factor of around 2.5 is achieved, and the enhancement of high-frequency components (>1 THz) shortens the THz pulse duration. Via complete characterization of THz properties and transmitted laser spectra, this nonlinear behavior is attributed to the extended effective interaction length for phase matching as a result of the self-phase modulation of the intense pump laser pulses. Numerical calculations well reproduce the experimental observation. Our results demonstrate a robust, efficient, strong-field (up to several MV/cm) THz source using the common sub-10 mJ and sub-100 fs Ti:sapphire laser systems without optical parametric amplifiers.

2.
BMC Womens Health ; 24(1): 182, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504245

RESUMO

BACKGROUND: Surgery combined with radiotherapy substantially escalates the likelihood of encountering complications in early-stage cervical squamous cell carcinoma(ESCSCC). We aimed to investigate the feasibility of Deep-learning-based radiomics of intratumoral and peritumoral MRI images to predict the pathological features of adjuvant radiotherapy in ESCSCC and minimize the occurrence of adverse events associated with the treatment. METHODS: A dataset comprising MR images was obtained from 289 patients who underwent radical hysterectomy and pelvic lymph node dissection between January 2019 and April 2022. The dataset was randomly divided into two cohorts in a 4:1 ratio.The postoperative radiotherapy options were evaluated according to the Peter/Sedlis standard. We extracted clinical features, as well as intratumoral and peritumoral radiomic features, using the least absolute shrinkage and selection operator (LASSO) regression. We constructed the Clinical Signature (Clinic_Sig), Radiomics Signature (Rad_Sig) and the Deep Transformer Learning Signature (DTL_Sig). Additionally, we fused the Rad_Sig with the DTL_Sig to create the Deep Learning Radiomic Signature (DLR_Sig). We evaluated the prediction performance of the models using the Area Under the Curve (AUC), calibration curve, and Decision Curve Analysis (DCA). RESULTS: The DLR_Sig showed a high level of accuracy and predictive capability, as demonstrated by the area under the curve (AUC) of 0.98(95% CI: 0.97-0.99) for the training cohort and 0.79(95% CI: 0.67-0.90) for the test cohort. In addition, the Hosmer-Lemeshow test, which provided p-values of 0.87 for the training cohort and 0.15 for the test cohort, respectively, indicated a good fit. DeLong test showed that the predictive effectiveness of DLR_Sig was significantly better than that of the Clinic_Sig(P < 0.05 both the training and test cohorts). The calibration plot of DLR_Sig indicated excellent consistency between the actual and predicted probabilities, while the DCA curve demonstrating greater clinical utility for predicting the pathological features for adjuvant radiotherapy. CONCLUSION: DLR_Sig based on intratumoral and peritumoral MRI images has the potential to preoperatively predict the pathological features of adjuvant radiotherapy in early-stage cervical squamous cell carcinoma (ESCSCC).


Assuntos
Carcinoma de Células Escamosas , Aprendizado Profundo , Neoplasias do Colo do Útero , Feminino , Humanos , Radioterapia Adjuvante , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/radioterapia , Radiômica , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapia , Imageamento por Ressonância Magnética , Estudos Retrospectivos
3.
Endoscopy ; 54(3): 290-298, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33271603

RESUMO

BACKGROUND: The likelihood of advanced or synchronous neoplasms is significantly higher in fecal immunochemical test (FIT)-positive individuals than in the general population. The magnitude of the colonoscopy-related complication rate in FIT-positive individuals remains unknown. This study aimed to elucidate the colonoscopy-related complication rate after a positive FIT result and compare it with the rate when colonoscopy was performed for other purposes. METHODS: Information regarding colonoscopy-related severe complications after a positive FIT result (FIT-colonoscopy) and ordinary colonoscopy during 2010-2014 was collected from the Taiwanese Colorectal Cancer Screening Program Database and National Health Insurance Research Database. Severe complications included significant bleeding, perforation, and cardiopulmonary events ≤ 14 days after colonoscopy. The number of events per 1000 procedures was used to quantify complication rates. Multivariate analysis was conducted to assess the association of various factors with severe complications associated with FIT-colonoscopy compared with ordinary colonoscopy. RESULTS: 319 114 FIT-colonoscopies (214 955 patients) were identified, 51 242 (16.1 %) of which included biopsy and 94 172 (29.5 %) included polypectomy. Overall, 2125 significant bleedings (6.7 ‰) and 277 perforations (0.9 ‰) occurred ≤ 14 days after FIT-colonoscopy. Polypectomy, antiplatelet use, and anticoagulant use were associated with higher risk of complications (adjusted odds ratio [aOR] 4.41, 95 % confidence interval [CI] 4.05-4.81); aOR 1.35, 95 %CI 1.12-1.53; aOR 1.88, 95 %CI 0.61-5.84, respectively). Compared with ordinary colonoscopy, FIT-colonoscopy involved significantly higher risk of significant bleeding (aOR 3.10, 95 %CI 2.90-3.32). CONCLUSIONS: FIT-colonoscopy was associated with a more than two-fold risk of significant bleeding, especially when polypectomy was performed.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Biópsia , Colonoscopia/efeitos adversos , Colonoscopia/métodos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Detecção Precoce de Câncer/efeitos adversos , Detecção Precoce de Câncer/métodos , Fezes , Humanos , Programas de Rastreamento/métodos , Sangue Oculto
4.
J Infect Dis ; 214(11): 1762-1772, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27658692

RESUMO

BACKGROUND: MASM, a novel derivative of matrine, has inhibitory effects on activation of macrophages, dendritic cells, and hepatic stellate cells and binds to ribosomal protein S5 (RPS5). This study was designed to evaluate the effect of MASM on murine-established lethal sepsis and its mechanisms. METHODS: Mouse peritoneal macrophages and RAW264.7 cells that were infected with recombinant lentiviruses encoding shRPS5 were incubated with lipopolysaccharide (LPS) in the absence or presence of MASM in vitro. Endotoxemia induced by LPS injection and sepsis induced by cecal ligation and puncture was followed by MASM treatment. RESULTS: MASM markedly attenuated LPS-induced release and messenger RNA expression of tumor necrosis factor α, interleukin 6, and NO/inducible NO synthase in murine peritoneal macrophages and RAW264.7 cells. Meanwhile, MASM inhibited LPS-induced activation of nuclear factor κB and MAPK pathways. Consistently, RPS5 suppressed LPS-induced inflammatory responses and at least in part mediated the antiinflammatory effect of MASM in vitro. Remarkably, delayed administration of MASM could significantly reduce mortality in mouse sepsis models, which was associated with the reduction in the inflammatory response, the attenuation in multiple organ injury, and the enhanced bacterial clearance. CONCLUSIONS: MASM could be further explored for the treatments of sepsis, especially for administration later after the onset of sepsis.


Assuntos
Alcaloides/administração & dosagem , Fatores Imunológicos/administração & dosagem , Inflamação/tratamento farmacológico , Inflamação/patologia , Quinolizinas/administração & dosagem , Sepse/tratamento farmacológico , Sepse/patologia , Animais , Modelos Animais de Doenças , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7/efeitos dos fármacos , Células RAW 264.7/imunologia , Análise de Sobrevida , Matrinas
5.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): o2729-30, 2010 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-21588939

RESUMO

The title compound, C(15)H(13)ClN(2)O(2)·CH(4)O, consists of a 4-chloro-N'-(4-meth-oxy-benzyl-idene)benzohydrazide (CMB) mol-ecule and a methanol mol-ecule of crystallization. It was obtained by the condensation of 4-meth-oxy-benzaldehyde with 4-chloro-benzohydrazide. In the CMB mol-ecule, the dihedral angle between the two benzene rings is 50.1 (3)°. The methanol mol-ecule is linked to the CMB mol-ecule through O-H⋯O and O-H⋯N hydrogen bonds. In the crystal, CMB mol-ecules are linked through inter-molecular N-H⋯O hydrogen bonds, involving the methanol mol-ecule, forming chains propagating along [010].

6.
Acta Chim Slov ; 67(3): 860-865, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33533420

RESUMO

The reactions of Ni(OAc)2 2H2O with Schiff base ligands 5-bromo-2-((cyclopentylimino)methyl)phenol (HL1) and 5-bromo-2-(((2-(isopropylamino)ethyl)imino)methyl)phenol (HL2) in methanol afforded two discrete trinuclear com-plexes [Ni3(L1)2(?2-?1:?1-OAc)2(DMF)2(BrSal)2] (1) and [Ni3(L2)2(?2-?1:?1-OAc)2(?2-?2:?1-OAc)2] (2), where BrSal is the monoanionic form of 4-bromosalicylaldehyde. The complexes were characterized by elemental analysis, IR and UV-Vis spectroscopy. The crystal structures of the complexes have been determined by X-ray crystallography. In both com-plexes, the nickel atoms are in octahedral coordination geometries. The L1 ligand coordinates to the nickel atoms through the phenolate O and imino N atoms, and the L2 ligand coordinates to the nickel atoms through the phenolate O, imino N and amino N atoms. The antimicrobial activities of the complexes were assayed.


Assuntos
Acetatos/farmacologia , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Complexos de Coordenação/farmacologia , Bases de Schiff/farmacologia , Acetatos/síntese química , Antibacterianos/síntese química , Antifúngicos/síntese química , Aspergillus niger/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Complexos de Coordenação/síntese química , Cristalografia por Raios X , Escherichia coli/efeitos dos fármacos , Ligantes , Testes de Sensibilidade Microbiana , Níquel/química , Salmonella typhi/efeitos dos fármacos , Bases de Schiff/síntese química
7.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 4): o852, 2009 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21582570

RESUMO

The title compound, C(15)H(13)ClN(2)O(2), was prepared by the reaction of 3-methoxy-benzaldehyde and 4-chloro-benzo-hydrazide in methanol. The asymmetric unit consists of two unique molecules, which are linked together in the form of a cross by N-H⋯O and N-H⋯N hydrogen bonds. The dihedral angles between the two benzene rings in the mol-ecules are 77.3 (1) and 44.1 (1)°. In the crystal structure, mol-ecules are linked through inter-molecular N-H⋯O hydrogen bonds, forming chains along the a axis.

8.
ACS Appl Mater Interfaces ; 10(14): 11941-11949, 2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-29557166

RESUMO

Electromagnetic protection in optoelectronic instruments such as optical windows and electronic displays is challenging because of the essential requirements of a high optical transmittance and an electromagnetic interference (EMI) shielding effectiveness (SE). Herein, we demonstrate the creation of an efficient transparent EMI shielding film that is composed of calcium alginate (CA), silver nanowires (AgNWs), and polyurethane (PU), via a facile and low-cost Mayer-rod coating method. The CA/AgNW/PU film with a high optical transmittance of 92% achieves an EMI SE of 20.7 dB, which meets the requirements for commercial shielding applications. A superior EMI SE of 31.3 dB could be achieved, whereas the transparent film still maintains a transmittance of 81%. The integrated efficient EMI SE and high transmittance are superior to those of most previously reported transparent EMI shielding materials. Moreover, our transparent films exhibit a highly reliable shielding ability in a complex service environment, with 98 and 96% EMI SE retentions even after 30 min of ultrasound treatment and 5000 bending cycles (1.5 mm radius), respectively. The comprehensive performance that is associated with the facile fabrication strategy imparts the CA/AgNW/PU film with great potential as an optimized EMI shielding material in emerging optoelectronic devices, such as flexible solar cells, displays, and touch panels.

9.
Nan Fang Yi Ke Da Xue Xue Bao ; 38(6): 742-747, 2018 Jun 20.
Artigo em Zh | MEDLINE | ID: mdl-29997099

RESUMO

OBJECTIVE: To study effect of electrical stimulations of different intensities on mitochondrial oxidative stress in C2C12 myotubes and explore the molecular mechanisms. METHODS: After 7 days of differentiation, C2C12 myotubes were subjected to electrical stimulations (15 V, 3Hz, 30 ms) for 60, 120, or 180 min, and the morphological changes of muscular tubes were observed under inverted microscope. The levels of MDA and SOD activity of the cells were detected, and flow cytometry was used to detect mitochondrial reactive oxygen species (ROS) and membrane potential. Western blotting was used to detect the expression of PGC1, AMPK-Ser485, AMPK-Thr172, and AMPK in the cells. RESULTS: No significant changes occurred in the morphology of C2C12 myotubes in response to electrical stimulations. Electrical stimulation for 60 min resulted in significantly increased levels of MDA, AMPK-Ser485 and AMPK-Thr172 in the cells (P<0.05); simulations of the cells for 120 and 180 min caused significantly increased MDA, ROS, mitochondrial ROS, AMPK-Ser485 and PGC1 along with marked reduction of mitochondrial membrane potential (P<0.05). CONCLUSION: Electrical stimulation significantly activates oxidative stress, and a longer stimulation time causes stronger mitochondrial oxidation. AMPK-Thr172 regulates oxidative stress induced by stimulations for a moderate time length, while AMPK-Ser485 and PGC1 function to modulate oxidative stress following prolonged stimulations.


Assuntos
Estimulação Elétrica/métodos , Malondialdeído/metabolismo , Mitocôndrias Musculares/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Estresse Oxidativo/fisiologia , Proteínas Quinases/metabolismo , Espécies Reativas de Oxigênio/análise , Superóxido Dismutase/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Humanos , Potencial da Membrana Mitocondrial/fisiologia , Fibras Musculares Esqueléticas/ultraestrutura , Fatores de Tempo
10.
Nan Fang Yi Ke Da Xue Xue Bao ; 37(10): 1322-1329, 2017 Oct 20.
Artigo em Zh | MEDLINE | ID: mdl-29070461

RESUMO

OBJECTIVE: To investigate the role of Rictor/mTORC2 in the formation of blood testis barrier (BTB), testicular development, and spermatogenesis. METHODS: Amh Cre positive mice homozygous for rictor loxP with Sertoli cell specific deletion of rictor were obtained by cross breeding Amh Cre mice with rictor loxP mice. The histology of the reproductive organs, seminiferous tubules and epididymis of the transgenic mice was observed with HE staining. The cell subgroups of the germ cells in the seminiferous tubule were detected by flow cytometry with propidium iodide labeling. The expression levels of Ki 67 and separase were detected with immunofluorescence assay, and the expression levels of BTB associated proteins were detected with immunofluorescence and Western blotting. RESULTS: Compared with the control (Amh Cre-, rictorloxP/loxP or rictorloxP/-) mice, the mice with Sertoli cell specific rictor deletion showed significantly decreased testicular weight and epididymis weight (P<0.05), significantly increased diploid cells (P<0.01), and decreased haploid cells (P<0.01) but comparable tetraploid cells and similar expression levels of Ki 67 and separase. The mice with rictor knockout also showed aberrant localization of BTB associated proteins, which were scattered over the whole seminiferous epithelium, but the expression levels of the protein remained stable. CONCLUSION: Rictor in testicular Sertoli cells is essential for maintaining BTB integrity and function and ensuring normal spermatogenesis in mice.


Assuntos
Barreira Hematotesticular/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Proteína Companheira de mTOR Insensível à Rapamicina/metabolismo , Células de Sertoli/metabolismo , Espermatogênese , Animais , Masculino , Camundongos , Camundongos Transgênicos , Epitélio Seminífero/metabolismo , Testículo/metabolismo
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