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Radiation-induced intestinal injury(RIII), a common complication of radiotherapy for pelvic malignancies, affects the quality of life and the radiotherapy efficacy for cancer. Currently, the main clinical approaches for the prevention and treatment of RIII include drug therapy, hyperbaric oxygen therapy, and surgical treatment. Among these methods, drug therapy is cost-effective. Traditional Chinese medicine(TCM) containing a variety of active components demonstrates mild side effects and good efficacy in preventing and treating RIII. Studies have proven that TCM active components, such as flavonoids, terpenoids, phenylpropanoids, and alkaloids, can protect the intestine against RIII by inhibiting oxidative stress, regulating the expression of inflammatory cytokines, modulating the mitochondrial apoptosis pathway, adjusting intestinal flora, and suppressing cell apoptosis. These mechanisms can help alleviate the symptoms of RIII. The paper aims to provide a theoretical reference for the discovery of new drugs for the prevention and treatment of RIII by reviewing the literature on TCM active components in the last 10 years.
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Alcaloides , Medicamentos Herbarios Chinos , Medicina Tradicional China , Medicamentos Herbarios Chinos/uso terapéutico , Medicamentos Herbarios Chinos/farmacología , Calidad de Vida , IntestinosRESUMEN
Sulfate-rich sedimentary rocks explored by the Opportunity rover during its 14-year surface mission at Meridiani Planum provide an invaluable window into the thousands of sulfate deposits detected on Mars via remote sensing. Existing models explaining the formation of martian sulfates can be generally described as either bottom-up, groundwater-driven playa settings or top-down icy chemical weathering environments. Here, we propose a hybrid model involving both bottom-up and top-down processes driven by freeze-thaw cycles. Freezing leads to cryo-concentration of acidic fluids from precipitations at the surface, facilitating rapid chemical weathering despite low temperatures. Cryosuction causes the upward migration of vadose water and even groundwater with dissolved ions, resulting in the accumulation of ions in near-surface environments. Evaporation precipitates salts, but leaching separates chlorides from sulfates during the thawing period. Freeze-thaw cycles, therefore, can enrich sulfates at the surface. While freeze-thaw is more commonly understood as a mechanism of physical weathering, we suggest that it is a fundamental aspect of chemical weathering on Mars.
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PURPOSE: Head and neck squamous cell carcinoma (HNSCC) is globally prevalent with high recurrence, low survival rate, and poor quality of life for patients. Derived from PAC-1, SM-1 can activate procaspase-3 and induce apoptosis in cancer cells to exert anti-tumor effects. However, the inhibitory effect of SM-1 on HNSCC after combination with radiation are unclear. This study aims to investigate the radiosensitizing effect of SM-1 on HNSCC in vitro and in vivo. METHODS: MTT method was used to detect the effect of SM-1 on the viability of HNSCC cell lines (HONE1, HSC-2, and CAL27). The effects of SM-1 combined with radiation on the survival index of HONE1, HSC-2, and CAL27 cell lines were determined by colony formation assay. Flow cytometry was used to investigate the effects of SM-1 and radiation combination on cell apoptosis and cell cycle, and western blot experiments were performed to detect the expression of apoptosis and cell cycle-related proteins. Finally, a xenograft tumor model of CAL27 was established to evaluate the anti-tumor effect of SM-1 combined with radiation in vivo. RESULTS: In vitro, SM-1 effectively inhibited the activity of HNSCC cell lines HONE1, HSC-2, and CAL27 cells, and synergistically showed anti-proliferation activity during combined irradiation. Meanwhile, anti-tumor effect of SM-1 on HNSCC was higher than that of Debio1143, and the radiosensitivity of cells was greatly increased. Flow cytometry and western blot analysis showed that SM-1 induced G2/M phase arrest of head and neck squamous cell carcinoma cells via inhibiting the expression of CyclinB1 and CDC2. Moreover, SM-1 activated caspase-3 activity and up-regulated the cleaved form of PARP1 to induce cell apoptosis. In vivo, SM-1 combined irradiation showed a good anti-tumor effect. CONCLUSION: SM-1 enhances HNSCC cell radiation sensitivity in vitro and in vivo, supporting its potential as a radiosensitizer for clinical trials in combination with radiotherapy.
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We report microbially facilitated synthesis of cadmium sulfide (CdS) nanostructured particles (NP) using anaerobic, metal-reducing Thermoanaerobacter sp. The extracellular CdS crystallites were <10 nm in size with yields of ~3 g/L of growth medium/month with demonstrated reproducibility and scalability up to 24 L. During synthesis, Thermoanaerobacter cultures reduced thiosulfate and sulfite salts to H2S, which reacted with Cd²âº cations to produce thermodynamically favored NP in a single step at 65 °C with catalytic nucleation on the cell surfaces. Photoluminescence (PL) analysis of dry CdS NP revealed an exciton-dominated PL peak at 440 nm, having a narrow full width at half maximum of 10 nm. A PL spectrum of CdS NP produced by dissimilatory sulfur reducing bacteria was dominated by features associated with radiative exciton relaxation at the surface. High reproducibility of CdS NP PL features important for scale-up conditions was confirmed from test tubes to 24 L batches at a small fraction of the manufacturing cost associated with conventional inorganic NP production processes.
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Compuestos de Cadmio/metabolismo , Espacio Extracelular/metabolismo , Nanoestructuras/química , Nanoestructuras/economía , Sulfuros/metabolismo , Thermoanaerobacter/metabolismo , Biomasa , Biotecnología , Compuestos de Cadmio/química , Compuestos de Cadmio/economía , Catálisis , Cristalización , Medios de Cultivo , Fermentación , Mediciones Luminiscentes , Nanotecnología , Reproducibilidad de los Resultados , Análisis Espectral , Sulfuros/química , Sulfuros/economía , Sulfitos/metabolismo , Azufre/metabolismo , Tiosulfatos/metabolismo , Factores de TiempoRESUMEN
The title compound, C21H42O5Si2, was synthesized from (3R,4S,5R)-methyl 3,5-bis-[(tert-butyl-dimethyl-sil-yl)-oxy]-4-hy-droxy-cyclo-hex-1-ene-carboxyl-ate by an esterification reaction. The cyclo-hexene ring adopts a half-chair conformation. In the crystal, mol-ecules are linked via C-Hâ¯O hydrogen bonds, forming helical chains propagating along [010].
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We report herein the design and synthesis of novel 4-aminoquinazoline derivatives based on the inhibitors of VEGFR-2 tyrosine kinases. The VEGFR-2 inhibitory activities of these newly synthesized compounds were also evaluated and compared with that of ZD6474. We found that most of target compounds had good inhibitory potency. In particular, compounds 1h, 1n and 1o were found to be 6, 2 and 2-fold more potent than the positive control ZD6474. The leading compound 1h also showed an in vivo activity against HepG2 human tumor xenograft model in BALB/c-nu mice.
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Química Farmacéutica/métodos , Quinazolinas/farmacología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Antineoplásicos/farmacología , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales/métodos , Inhibidores Enzimáticos/farmacología , Células Hep G2 , Humanos , Concentración 50 Inhibidora , Ratones , Ratones Desnudos , Modelos Químicos , Trasplante de Neoplasias , Piperidinas/farmacología , Quinazolinas/síntesis química , Receptor 2 de Factores de Crecimiento Endotelial Vascular/químicaRESUMEN
Manganese (hydr)oxides (MnO(x)) is a powerful oxidant in the oxidation of As(III) in natural environment. Under some circumstances, Mn(II) can be oxidized to MnO(x) which in turn accelerates the oxidation of As(III). However, to the best of our knowledge, little is known regarding how Mn(II) affects the oxidation of both the dissolved and the adsorbed As(III) in aquatic environments. In this study, effects of abiotic oxidation of Mn(II) on the oxidation of As(III) were investigated. Kinetic results as well as TEM and XRD analyses confirmed the formation of amorphous MnO(x) after sorption of Mn(II) on hematite nano-particles under oxic conditions. Mn(II) was oxidized to Mn(III) and then to Mn(IV), and this process was dependent upon pH and Mn(II) concentrations. The newly formed MnO(x) played an important role in the further oxidation of the dissolved and the adsorbed As(III) on hematite, and the oxidation rate of As(III) increased with the rising Mn(II) concentrations. As the adsorbed As(III) was oxidized to As(V), a fraction of As(V) was released into the solution, which increased the mobility of As. The present study reveals that abiotic oxidation of Mn(II) affects the oxidation of As(III) in aquatic environment.
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Arseniatos/química , Compuestos Férricos/química , Manganeso/química , Nanoestructuras/química , Oxidación-Reducción , Adsorción , Concentración de Iones de Hidrógeno , CinéticaRESUMEN
In the title compound, C(13)H(10)FN(3)O(3), the dihedral angle between the fluoro-phenyl and nitro-phenyl ring planes is 6.51â (9)°. The crystal structure features N-Hâ¯O hydrogen bonds.
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BACKGROUND: Postoperative atrial fibrillation is a common consequence of cardiac sur-gery with increased stroke complications and mortality. Although dexmedetomidine is thought to prevent postoperative atrial fibrillation and stroke because of its sympa-tholytic and anti-inflammatory properties, data from different studies show the effect of dexmedetomidine on postoperative atrial fibrillation and stroke uncertain in adult patients with cardiac surgery. METHODS: A database including EMBASE, PubMed, and Cochrane CENTRAL was searched for randomized controlled trials comparing dexmedetomidine with placebo or other anesthetic drugs in adult cardiac surgery. The primary outcome was the incidence of postoperative atrial fibrillation. The secondary outcomes were the incidence of postop-erative stroke, mechanical ventilation duration, intensive care unit length of stay, hospi-tal length of stay, and mortality. RESULTS: Eighteen trials with a total of 2933 patients were enrolled in the meta-analyses. Compared with controls, dexmedetomidine significantly reduced the incidence of post-operative atrial fibrillation [odds ratio, 0.82; 95% CI, 0.69-0.98; P = .03]. There was no sig-nificant difference between groups in stroke (odds ratio, 1.36; 95% CI, 0.59-3.16; P = .47), mechanical ventilation duration [weighted mean difference, -0.17; 95% CI, -0.35 to 0.14;P=.39], intensive care unit length of stay (weighted mean difference, -0.03; 95% CI,-0.93 to 0.87; P = .95), hospital length of stay (weighted mean difference, -0.04; 95% CI,-0.40 to 0.32; P = .83) and mortality (odds ratio, 0.72; 95% CI, 0.32-1.60; P = .42). CONCLUSION: Perioperative dexmedetomidine reduced the incidence of postoperative atrial fibrillation in adult patients undergoing cardiac surgery. But there was no signifi-cant difference in the incidence of stroke, mechanical ventilation duration, intensive care unit length of stay, hospital length of stay, and mortality.
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Fibrilación Atrial , Procedimientos Quirúrgicos Cardíacos , Dexmedetomidina , Accidente Cerebrovascular , Adulto , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/epidemiología , Fibrilación Atrial/prevención & control , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Dexmedetomidina/uso terapéutico , Humanos , Tiempo de Internación , Complicaciones Posoperatorias/tratamiento farmacológico , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto , Respiración Artificial , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & controlRESUMEN
1. Whether damage to the blood-brain barrier (BBB) occurs in remote areas after a focal cortical lesion remains unknown. The present study investigated tight junction-related proteins and tight junction microstructure in the ipsilateral thalamus during the acute stage after middle cerebral artery occlusion (MCAO) and cortical aspiration lesion (CAL) in rats. 2. Thirty-six hypertensive and normotensive rats were subjected to MCAO or CAL; another 18 rats in each group were submitted to sham operation. Zonula Occluden (ZO)-1, occludin and albumin were detected by western blotting 12 and 24 h after surgery. Tight junction microstructure was evaluated using electron microscopy, whereas albumin location in the ipsilateral thalamus was determined using double immunostaining for albumin and occludin or albumin and neuronal nuclei (NeuN) 24 h after surgery. 3. Twenty-four hours after MCAO or CAL, occludin expression was reduced to 78.4% and 81.3%, respectively, compared with control. A reduction in ZO-1 expression in the ipsilateral thalamus (to 79%) was seen only after CAL (P < 0.05). Membrane contact at the tight junction was discontinuous in the ipsilateral thalamus in both MCAO and CAL rats. Albumin levels were 23.2% and 82.5% higher in the ipsilateral thalamus after MCAO and CAL, respectively (P < 0.05). The percentage of the albumin-positive area that coincided with the occludin-positive area in the MCAO and CAL groups was 76.8% and 64.6%, respectively, indicating that albumin was mainly localized around the microvessels. 4. The results of the present study suggest that tight junction integrity decreases during the acute stage in the ipsilateral thalamus after MCAO and CAL in rats.
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Barrera Hematoencefálica/fisiopatología , Corteza Cerebral/fisiopatología , Infarto Cerebral/fisiopatología , Infarto de la Arteria Cerebral Media/fisiopatología , Tálamo/fisiopatología , Uniones Estrechas/patología , Albúminas/metabolismo , Animales , Barrera Hematoencefálica/metabolismo , Corteza Cerebral/metabolismo , Infarto Cerebral/metabolismo , Hipertensión/metabolismo , Hipertensión/fisiopatología , Infarto de la Arteria Cerebral Media/metabolismo , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Microvasos/metabolismo , Microvasos/fisiopatología , Ocludina , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Ratas , Ratas Sprague-Dawley , Tálamo/metabolismo , Uniones Estrechas/metabolismo , Uniones Estrechas/ultraestructura , Proteína de la Zonula Occludens-1RESUMEN
A series of novel 7-(3-aminopyrrolo[3,4-c]pyrazol-5(2H,4H,6H)-yl)-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid derivatives was designed, synthesized and characterized by (1)H-NMR, MS and HRMS. These fluoroquinolones were evaluated for their in-vitro antibacterial activity against representative Gram-positive and Gram-negative strains. Generally, all of the target compounds display rather weak potency against the tested Gram-negative strains, but most of them exhibit good potency in inhibiting the growth of S. aureus including methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis including methicillin-resistant S. epidermidis (MRSE) (MIC: 0.125-8 µg/mL). In particular, the compound 9g is 2 to 32 fold more potent than gemifloxacin (GM), moxifloxacin (MX), gatifloxacin (GT), and levofloxacin (LV) against S. pneumoniae 08-3, K. pneumoniae 09-23, and P. aeruginosa ATCC27853, 4 to 32 fold more potent than MX, GM, and LV against K. pneumoniae 09-21, and more active than or comparable to the four reference drugs against P. aeruginosa 09-32.
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Antibacterianos/síntesis química , Antibacterianos/farmacología , Fluoroquinolonas/síntesis química , Fluoroquinolonas/farmacología , Antibacterianos/análisis , Antibacterianos/química , Farmacorresistencia Bacteriana , Fluoroquinolonas/análisis , Fluoroquinolonas/química , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Staphylococcus epidermidis/efectos de los fármacos , Relación Estructura-ActividadRESUMEN
In the title compound, C(7)H(8)N(2)O(5)S·C(2)H(6)O, the dihedral angle between the aromatic ring and the nitro group is 8.78â (9)° and the S atom is displaced by 0.226â (3)â Å from the plane of the aromatic ring. In the crystal, the ethanol mol-ecule is involved in hydrogen bonding to two separate sulfonamide mol-ecules, as a donor in an O-Hâ¯O inter-action and as an acceptor in an N-Hâ¯O inter-action. Weak C-Hâ¯O hydrogen bonding is also present.
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In the mol-ecule of the title compound, C(12)H(20)N(4)O(2), the dihydro-piperidine ring assumes a half-chair conformation. In the crystal, cllassical N-Hâ¯O and N-Hâ¯N inter-molecular hydrogen bonds link mol-ecules into double chains along the a axis.
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In the title mol-ecule, C(21)H(14)ClFIN(3)O, the bicyclic ring system has a twisted conformation; the two fused rings form a dihedral angle of 4.5â (1)°. The dihedral angles between the fused ring system and the benzene rings are 27.3â (6) and 5.3â (5)° while the dihedral angle between the benzene rings is 22.0â (5)°. In the crystal structure, weak inter-molecular N-Hâ¯N hydrogen bonds link the mol-ecules into chains propagating in [100]. A short inter-molecular distance of 3.806â (3)â Å between the centroids of the fluorobenzene and iodobenzene rings suggests the existence of π-π stacking inter-actions.
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BACKGROUND: Giant paraesophageal hiatal hernias (HH) are very infrequent, and their spectrum of clinical manifestations is large. Giant HH mainly occurs in elderly patients, and its relationship with anemia has been reported. For the surgical treatment of large HH, Nissen fundoplication is the most common antireflux procedure, and the reinforcement of HH repair with a patch (either synthetic or biologic) is still debatable. CASE SUMMARY: We report on a case of giant paraesophageal HH in a middle-aged male patient with reflux symptoms and severe anemia. After performing a series of tests and diagnostic approaches, results showed a complete intrathoracic stomach associated with severe iron deficiency anemia. The patient underwent successful laparoscopic hernia repair with mesh reinforcement and Nissen fundoplication. Postoperatively, reflux symptoms were markedly relieved, and the imaging study showed complete reduction of the hernia sac. More importantly, anemia was resolved, and hemoglobin, serum iron and ferritin level were returned to the normal range. The patient kept regular follow-up appointments and remained in a satisfactory condition. CONCLUSION: This case report highlights the relationship between large HH and iron deficiency anemia. For the surgical treatment of large HH, laparoscopic repair of large HH combined with antireflux procedure and mesh reinforcement is recommended.
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The title compound, [Mg(C(6)H(5)N(2)O(4))(2)(H(2)O)(2)], was prepared by reaction of Mg(NO(3))(2) and 2-methyl-1H-imidazole-4,5-dicarboxylic acid under hydro-thermal conditions. The Mg(II) atom lies on an inversion centre and displays a distorted octa-hedral coordination geometry. An extended three-dimensional network of inter-molecular O-Hâ¯O and N-Hâ¯O hydrogen bonds stabilizes the crystal structure.
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In the title compound, [Cu(C(6)H(5)N(2)O(4))(2)], the copper(II) atom lies on an inversion centre and is in an N(2)O(2) four-coordinate environment with a nearly regular square-planar geometry. An extended network of intra-molecular O-Hâ¯O and inter-molecular N-Hâ¯O and C-Hâ¯O hydrogen bonds stabil-izes the crystal structure.
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OBJECTIVE: To investigate the effects of psychological stress on xanthine oxidase (XO) expression, activity and related markers in adipose tissue of mice. METHODS: Twenty male Kunming mice were randomly divided into two groups (10 in each group), stress group and control group (10 in each group). Stress group were restrained in self-made restraint device for 2 hours per day for 14 days, then blood samples and white adipose tissues(WAT) were collected. The expression levels of XO and NADPH oxidase-4 (Nox-4) in WAT were detected by immunohistochemistry. The expression of XO, Nox-4, antioxidant proteins (manganese superoxide dismutase (Mn SOD), glutathione peroxidase (GSH-Px), and catalase (CAT)), adipocytokines (adiponectin (ADPN), monocyte chemotactic protein 1 (MCP-1), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α)) in WAT were further detected by quantitative PCR. Relative expressions of glucose metabolism (insulin receptor substrate-1(IRS-1) and glucose transporter type 4(GLUT-4)) and thrombin(tissue factor (TF) and plasminogen activator inhibitor 1 (PAI-1))were measured. XO activity and serum concentrations of (triglyceride (TG), total cholesterol (T-Cho), free fatty acid, (FFA), and uric acid (UA)) were detected by ELISA. RESULTS: XO expressed in stress mice inguinal WAT was deeper and more abundant than that of control group, mainly expressed in adipocytes. RT-PCR and ELISA results showed that the levels of XO mRNA, serum XO concentration and the activities of XO enzyme in WAT of stress group were significantly higher than those of control group(P ï¼0.01). Compared with control group the concentrations of free fatty acid (FFA) and uric acid (UA) in stress group were increased significantly than in control group (Pï¼ 0.01). Nox-4 positive cells mainly expressed in adipocytes. The expression of Nox-4 in WAT of stress group was significantly higher(P ï¼0.01); The levels of antioxidant proteins (Mn-SOD, GSH-Px, Catalase) in WAT of stress group were significantly lower (Pï¼ 0.01). WAT in stress group showed a large number of infiltration reactions and inflammatory changes of monocytes, neutrophils, eosinophils and plasma cells. Stress significantly decreased the expression of adiponectin in WAT, and significantly increased the expressions of MCP-1, IL-6 and TNF-α (Pï¼0.01). The levels of IRS-1 and GLUT-4 in WAT of stress mice were increased significantly (Pï¼ 0.01). The expressions of TF and PAI-1 in WAT of stress mice and blood concentrations were significantly higher (Pï¼0.01). CONCLUSION: Stress can induce excessive expressions of XO in adipose tissue, which eventaully can lead to adipose inflammation, glycometabolism and abnormal prothrombin.
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Tejido Adiposo/enzimología , Estrés Psicológico/metabolismo , Xantina Oxidasa/metabolismo , Adipoquinas/metabolismo , Animales , Antioxidantes/metabolismo , Citocinas/metabolismo , Masculino , Ratones , Distribución AleatoriaRESUMEN
The aim of this study was to elaborate the correlation between metastasis-associated protein (MTA) family and the occurrence, progression, prognosis and chemotherapy efficiency in nasopharyngeal carcinoma (NPC).The expression of MTA1, MTA2 and MTA3 protein were detected by immunohistochemistry in a tissue microarray (TMAs) which contains tissue samples of 152 NPC patients embedded by formalin-fixed paraffin. The MTA proteins were mainly expressed in the nuclei of NPC tissues and the correlations between MTAs expression and clinical parameters as well as prognosis of NPC patients showed ethnical differences according to statistically analysis. The results showed that in Han ethnic group, MTA1 expression was positively correlated with N staging, while the expression of MTA2 was negatively correlated with age, and the expression of MTA3 was positively correlated with gender. Patients with high MTA1 expression had poorprognosis. In Zhuang ethnic group, only MTA3 expression was positively correlated with age, recurrence and metastasis of NPC patients; neither MTA1 nor MTA2 expression had any correlation with clinical indexes. Patients with high MTA3 expression had unfavorable prognosis. In addition, our results showed that overall survival among Zhuang NPC patients with low expression of MTA2 increased significantly owing to "carboplatin + fluorouracil" chemotherapy. This therapeutic success, however, did not translate to longer overall survival among Han NPC patients. The biological function of MTA protein family in NPC patients was different among different ethnic groups. In conclusion, we demonstrated that MTAs had a certain tumor promoting function in patients with NPC, and the biological functions of MTAs might be ethnic differences, which suggesting MTAs to be important markers for guiding clinical treatment of NPC.
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Since Earth's biochemistry is carbon-based and water-borne, the main strategies for searching for life elsewhere are "follow the carbon" and "follow the water." Recently, however, there is a growing focus on the prospect that putative exotic life on other planets could rely on unearthly biochemistries. Here, we hypothesize a novel oxygen-free organic chemistry for supporting potential exotic biosystems, which is named CHN biochemistry. This oxygen-free CHN biochemistry starts from simple oxygen-free species (including hydrocarbons, hydrogen cyanide, and nitriles) and produces a range of functional macromolecules that may function in similar ways to terran macromolecules, such as sugars (cyanosugars), acids (cyanoacids), amino acids (amino cyanoacids), and nucleobases (cyanonucleobases). These CHN macromolecules could further interact with each other to generate higher "cyanoester" and "cyanoprotein" systems. In addition, theoretical calculations indicate that the energy changes of some reactions are consistent with their counterparts in Earth's biochemistry. The CHN biochemistry-based life would be applicable in habitats with a low bioavailability of oxygen, such as the alkane lakes of Titan and non-aquatic liquids on extrasolar bodies. Key Words: Oxygen-free biochemistry-Titan-Hydrocarbons-Hydrogen cyanide-Nitriles. Astrobiology 17, 1173-1181.