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1.
J Am Chem Soc ; 140(47): 16275-16283, 2018 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-30403348

RESUMEN

Precise control over helical chirality and dimensions of molecular self-assemblies, a remaining challenge for both chemists and materials scientists, is the key to manipulate the property and performance of supramolecular materials. Herein, we report that a cholesterol-azopyridine conjugate could self-assemble into organogels with photocontrollable dimensional transition from 2D microbelts to 1D nanotubes and finally to 0D nanoparticles. The E/ Z-Photoisomerization of the 4-azopyridine unit is the major driving force for the dimensional transformation. Furthermore, the self-assembled structures were observed to exhibit metal ion-mediated helicity inversion through the metal coordination. These observations were collectively confirmed by several techniques including scanning electron microscopy, atomic force microscopy, circular dichroism, and X-ray crystallography. The rational design of building blocks for the construction of dimension and chirality controllable self-assembly systems may lead to versatile applications in smart display, advanced optoelectronic device, and supramolecular asymmetric catalysis.

2.
J Am Chem Soc ; 140(20): 6467-6473, 2018 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-29733593

RESUMEN

While manipulating the helicity of nanostructures is a challenging task, it attracts great research interest on account of its crucial role in better understanding the formation mechanisms of helical systems. For the supramolecular chirality in self-assembly systems, one challenge is how to understand the origin of supramolecular chirality and inherent helicity information on nanostructures regulated by functionality-oriented stacking modes (such as J- and H-aggregation) of building blocks. Herein, two-component hydrogels were prepared by phenylalanine-based enantiomers and achiral bis(pyridinyl) derivatives, where helical nanofibers with inverse handedness as well as controllable helical pitch and diameter were readily obtained through stoichiometric coassembly of these building blocks. The helix inversion was achieved by the transition between the J- and H-aggregation of bis(pyridinyl) derivatives, which was collectively confirmed by circular dichroism, scanning electron microscopy, Fourier transform infrared spectroscopy, and single X-ray crystallography. Interestingly, the helical coassemblies with opposite handedness could be obtained not only from the enantiomeric building blocks but also from the chiral monomers with the same configurational chirality by exchanging achiral additives. This work provides insight into the origin and helicity inversion of supramolecular chirality in molecular self-assembly systems and may shine light on the precise fabrication of chiral nanostructures for potential applications in smart display devices, optoelectronics, and biological systems.

3.
Appl Immunohistochem Mol Morphol ; 29(8): 585-591, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-33734107

RESUMEN

This research aims to explore the diagnostic and prognostic value of ubiquitin-conjugating enzyme E2 variant 2 (UBE2V2) in lung adenocarcinoma (LUAD). The expression of UBE2V2 in clinical specimens was evaluated by bioinformatics analyses and immunohistochemistry. Bioinformatics analyses relying on the The Cancer Genome Atlas (TCGA) database suggested the elevated UBE2V2 mRNA levels in LUAD in comparison to adjacent normal tissues. Gene set enrichment analyses and gene ontology term enrichment analyses further showed the involvement of UBE2V2 in the modulation of cell cycle and immune associated signaling. The correlation analyses in TCGA LUAD data set revealed the positive correlation between UBE2V2 and CCNE1, CCNE2, CCNA2, CCNB1, CCNB2, cyclin-dependent kinase (CDK)2, CDK4, and CDK1 at the mRNA level. Moreover, UBE2V2 mRNA levels were positively correlated with PD-L1 mRNA levels, the T classification, and poor survival of LUAD patients, and were negatively correlated with type II interferon response. Consistent with the results obtained from TCGA data mining, immunohistochemistry demonstrated that UBE2V2 protein levels were upregulated in LUAD in comparison to normal tissues and were positively associated with T classification. Intriguingly, a positive correlation between UBE2V2 protein levels and PD-L1 expression was also elucidated in clinical samples. Besides, UBE2V2 expression indicated a poor prognosis in LUAD patients. Our study found that UBE2V2 was identified as an independent prognostic indicator for LUAD and might serve as an alternative target for LUAD treatment.


Asunto(s)
Adenocarcinoma del Pulmón , Antígeno B7-H1/biosíntesis , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares , Proteínas de Neoplasias/biosíntesis , Enzimas Ubiquitina-Conjugadoras/biosíntesis , Adenocarcinoma del Pulmón/metabolismo , Adenocarcinoma del Pulmón/mortalidad , Adenocarcinoma del Pulmón/patología , Femenino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino
4.
Medicine (Baltimore) ; 98(48): e18095, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31770228

RESUMEN

RATIONALE: Transcatheter arterial chemoembolization (TACE) is recognized as one of the most commonly used modalities for non-surgical treatment for advanced hepatocellular carcinoma (HCC). Ectopic lipiodol embolism is an extremely rare complication of TACE. PATIENT CONCERNS: A 61-year-old man who had a 10-year history of cirrhosis caused by hepatitis B infection was diagnosed with ascites and HCC. Subsequently, the patient underwent TACE. However, he experienced persistent left upper abdominal pain, poor appetite, nausea, moderate fever and accompanied by elevation of serum and urine amylase on the 2nd and 3nd day after treatment. DIAGNOSES: The patient was diagnosed as having acute hemorrhagic necrotizing pancreatitis based on biochemical and inflammatory markers and CT findings. We deduced that the acute necrotizing pancreatitis was caused by a small branch of the left hepatic artery feeding the pancreas tail and embolizing the drug and lipiodol shunting to the tail of the pancreas. INTERVENTIONS: The patient was treated for 5 days according to the comprehensive treatment of acute necrotizing pancreatitis, by the inhibition of the secretion of pancreatic juice, relieving pain, and total parenteral nutrition and forbidding diet. The symptoms of the patient were observed to improve, and SAMS and urinary amylase (UAMS) level decreased to 143 IU/L and 254 IU/L, respectively and oral diet was permitted. OUTCOME: After a period of 2 weeks, the contrast abdominal CT showed slightly decreased fluid collection of the peri-pancreatic space. Moreover, it also showed flocculous and linear high-density shadow in the pancreatic tail, suggesting lipiodol deposition in the pancreatic tail. Subsequently, the symptoms were observed to abate, and the patient left the hospital. On the 21st day after TACE, the patient had a follow up in our outpatient department; the biochemical characteristics and inflammatory markers were observed to be normal CONCLUSION:: AP is still a rare complication after TACE. Etiology is still attributed to the occurrence of shunting and embolization drug reflux. Strategies strengthening the catheter tip that is placed as close to the distal branches of the hepatic artery for the possible careful injection of embolic materials is still the key to avoid post-TACE AP.


Asunto(s)
Antineoplásicos/efectos adversos , Quimioembolización Terapéutica/efectos adversos , Embolia/inducido químicamente , Aceite Etiodizado/efectos adversos , Pancreatitis Aguda Necrotizante/etiología , Carcinoma Hepatocelular/terapia , Humanos , Neoplasias Hepáticas/terapia , Masculino , Persona de Mediana Edad , Páncreas/irrigación sanguínea
5.
World J Clin Cases ; 7(17): 2573-2579, 2019 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-31559295

RESUMEN

BACKGROUND: The portosystemic shunt is the pathway between the portal vein (PV) and systemic circulation. A spontaneous intrahepatic portosystemic shunt (SPISS) is a rare portosystemic shunt type. Here we report an extremely rare type of SPISS, a spontaneous intrahepatic PV-inferior vena cava shunt (SPIVCS). CASE SUMMARY: A 66-year-old woman was admitted to our hospital with the complaint of abdominal distention and a decreased appetite for 1 mo. The patient had a 20-year history of hepatitis B surface antigen positivity and a 5-year history of cirrhosis. She had been treated with Chinese herbal medicine for a long time. Liver function tests showed: alanine aminotransferase, 35 U/L; aspartate aminotransferase, 42 U/L; serum albumin (ALB) 32.2 g/L; and serum ascites ALB gradient, 25.2 g/L. Abdominal ultrasonography and enhanced computed tomography showed that the left branch of the PV was thin and occluded; the right branch of the PV was thick and showed a vermicular dilatation vein cluster in the upper pole of the right kidney that branched out and converged into the inferior vena cava from the bare area of the lower right posterior lobe of the liver. We diagnosed her with an extremely rare SPIVCS caused by portal hypertension and provided symptomatic treatment after admission. One week later, her symptoms disappeared and she was discharged. CONCLUSION: SPIVCS is a rare portosystemic shunt with a clear history of cirrhosis and portal hypertension. Clarifying the type PV shunt has important clinical significance.

6.
World J Gastroenterol ; 24(41): 4716-4720, 2018 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-30416319

RESUMEN

Progressive familial intrahepatic cholestasis type 3 is caused by a mutation in the ATP-binding cassette, subfamily B, member 4 (ABCB4) gene encoding multidrug resistance protein 3. A 32-year-old woman with a history of acute hepatitis at age 9 years was found to have jaundice during pregnancy in 2008, and was diagnosed as having intrahepatic cholestasis of pregnancy. In 2009, she underwent cholecystectomy for gallstones and chronic cholecystitis. However, itching and jaundice did not resolve postoperatively. She was admitted to our hospital with fatigue, jaundice, and a recently elevated γ-glutamyl transpeptidase level. Liver biopsy led to the diagnosis of biliary cirrhosis with ductopenia. Genetic testing revealed a pathogenic heterozygous mutation, ex13 c.1531G > A (p.A511T), in the ABCB4 gene. Her father did not carry the mutation, but her mother's brother carried the heterozygous mutation. We made a definitive diagnosis of familial intrahepatic cholestasis type 3. Her symptoms and liver function improved after 3 mo of treatment with ursodeoxycholic acid.


Asunto(s)
Subfamilia B de Transportador de Casetes de Unión a ATP/deficiencia , Conductos Biliares Intrahepáticos/patología , Colestasis Intrahepática/diagnóstico , Cirrosis Hepática/diagnóstico , Ácido Ursodesoxicólico/uso terapéutico , gamma-Glutamiltransferasa/sangre , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Adulto , Biopsia , Colestasis Intrahepática/tratamiento farmacológico , Colestasis Intrahepática/genética , Colestasis Intrahepática/patología , Análisis Mutacional de ADN , Femenino , Pruebas Genéticas , Humanos , Hígado/patología , Cirrosis Hepática/genética , Cirrosis Hepática/patología
7.
ACS Nano ; 11(12): 11880-11889, 2017 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-29140680

RESUMEN

Probing the supramolecular chirality of assemblies and controlling their handedness are closely related to the origin of chirality at the supramolecular level and the development of smart materials with desired handedness. However, it remains unclear how achiral residues covalently bonded to chiral amino acids can function in the chirality inversion of supramolecular assemblies. Herein, we report macroscopic chirality and dynamic manipulation of chiroptical activity of hydrogels self-assembled from phenylalanine derivatives, together with the inversion of their handedness achieved solely by exchanging achiral substituents between oligo(ethylene glycol) and carboxylic acid groups. This helicity inversion is mainly induced by distinct stacking mode of the self-assembled building blocks, as collectively confirmed by scanning electron microscopy, circular dichroism, crystallography, and molecular dynamics calculations. Through this straightforward approach, we were able to invert the handedness of helical assemblies by merely exchanging achiral substituents at the terminal of chiral gelators. This work not only presents a feasible strategy to achieve the handedness inversion of helical nanostructures for better understanding of chiral self-assembly process in supramolecular chemistry but also facilities the development of smart materials with controllable handedness in materials science.

8.
PLoS One ; 11(3): e0149353, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26938720

RESUMEN

BACKGROUND: Apoptosis plays a critical role in controlling the proliferation and differentiation of germ cells during spermatogenesis. Dysregulation of the fine-tuned balance may lead to the onset of testicular diseases. In this study, we investigated the activation status of apoptosis pathways in the testicular tissues under the background of an asthmatic mouse model. METHODS: Ten BALB/c mice were divided into two groups: the acute asthma group and the control group. In the acute asthma group, ovalbumin (OVA)-sensitized mice were challenged with aerosolized OVA for 7 days, while the control group was treated with physiological saline. After that, both epididymis and testis were collected to determine the sperm count and motility. Apoptosis in the testis was evaluated by DNA ladder, immunochemistry and further by PCR array of apoptosis-related genes. Finally, the cleavage of caspase-3 and poly ADP-ribose polymerase (PARP) was determined by western blot and the enzymatic activities of caspase-9 and 3/7 were assessed using Caspase-Glo kits. RESULTS: Compared with control mice, significant decreases in the body weight, testis weight, sperm count and motility were seen in the experimental group. DNA ladder and immunochemistry showed significant increase in apoptotic index of the asthmatic testis, whereas a decrease in mRNA expression of Bcl-2 and increases in Bax, BNIP3, caspase-9, and AIF were observed in the asthma group. Furthermore, protein levels of AIF were significantly upregulated, while the translational expression of Bcl-2 was downregulated markedly. Consistently, caspase-9 activity in the testis of asthma mice was significantly higher than that of the control group. CONCLUSION: Collectively, these results showed that Bcl-2-caspase-9 apoptosis pathway was clearly activated in the testis of asthmatic mice with the increased expression of apoptosis-related genes and proteins. To our knowledge, this is the first report demonstrating that asthma could lead to the activation of the mitochondrial apoptosis signaling pathway in the mouse testis.


Asunto(s)
Asma/genética , Caspasa 9/genética , Epidídimo/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Espermatozoides/metabolismo , Testículo/metabolismo , Enfermedad Aguda , Animales , Apoptosis/genética , Factor Inductor de la Apoptosis/genética , Factor Inductor de la Apoptosis/metabolismo , Asma/inducido químicamente , Asma/metabolismo , Asma/patología , Peso Corporal , Caspasa 3/genética , Caspasa 3/metabolismo , Caspasa 7/genética , Caspasa 7/metabolismo , Caspasa 9/metabolismo , Epidídimo/patología , Regulación de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ovalbúmina , Poli(ADP-Ribosa) Polimerasas/genética , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal , Recuento de Espermatozoides , Motilidad Espermática/genética , Espermatogénesis/genética , Espermatozoides/patología , Testículo/patología
9.
PLoS One ; 9(4): e95228, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24760004

RESUMEN

Lung cancer is the most common malignancy and the leading cause of cancer deaths worldwide. While smoking is by far the leading cause of lung cancer, other environmental and genetic factors influence the development and progression of the cancer. Since unique mutations patterns have been observed in individual cancer samples, identification and characterization of the distinctive lung cancer molecular profile is essential for developing more effective, tailored therapies. Until recently, personalized DNA sequencing to identify genetic mutations in cancer was impractical and expensive. The recent technological advancements in next-generation DNA sequencing, such as the semiconductor-based Ion Torrent sequencing platform, has made DNA sequencing cost and time effective with more reliable results. Using the Ion Torrent Ampliseq Cancer Panel, we sequenced 737 loci from 45 cancer-related genes to identify genetic mutations in 76 human lung cancer samples. The sequencing analysis revealed missense mutations in KRAS, EGFR, and TP53 genes in the breast cancer samples of various histologic types. Thus, this study demonstrates the necessity of sequencing individual human cancers in order to develop personalized drugs or combination therapies to effectively target individual, breast cancer-specific mutations.


Asunto(s)
Receptores ErbB/genética , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogénicas/genética , Análisis de Secuencia de ADN/métodos , Proteína p53 Supresora de Tumor/genética , Proteínas ras/genética , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/genética , Análisis Mutacional de ADN/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Proteínas Proto-Oncogénicas p21(ras)
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