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1.
FASEB J ; 37(12): e23304, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37971426

RESUMO

The phosphatase and tensin congeners (Pten) gene affects cell growth, cell proliferation, and rearrangement of connections, and it is closely related to cellular senescence, but it remains unclear the role of muscle-Pten gene in exercise against age-related deterioration in skeletal muscle and mortality induced by a high-salt diet (HSD). In here, overexpression and knockdown of muscle Pten gene were constructed by building MhcGAL4 /PtenUAS-overexpression and MhcGAL4 /PtenUAS-RNAi system in flies, and flies were given exercise training and a HSD for 2 weeks. The results showed that muscle Pten knockdown significantly reduced the climbing speed, climbing endurance, GPX activity, and the expression of Pten, Sirt1, PGC-1α genes, and it significantly increased the expression of Akt and ROS level, and impaired myofibril and mitochondria of aged skeletal muscle. Pten knockdown prevented exercise from countering the HSD-induced age-related deterioration of skeletal muscle. Pten overexpression has the opposite effect on skeletal muscle aging when compared to it knockdown, and it promoted exercise against HSD-induced age-related deterioration of skeletal muscle. Pten overexpression significantly increased lifespan, but its knockdown significantly decreased lifespan of flies. Thus, current results confirmed that differential expression of muscle Pten gene played an important role in regulating skeletal muscle aging and lifespan, and it also affected the adaptability of aging skeletal muscle to physical exercise since it determined the activity of muscle Pten/Akt pathway and Pten/Sirt1/PGC-1α pathway.


Assuntos
Condicionamento Físico Animal , Sirtuína 1 , Animais , Sirtuína 1/metabolismo , Drosophila/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Condicionamento Físico Animal/fisiologia , Músculo Esquelético/metabolismo , Dieta , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo
2.
Plant Cell Environ ; 46(9): 2649-2666, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37312624

RESUMO

Carbon isotope composition of tree-ring (δ13 CRing ) is a commonly used proxy for environmental change and ecophysiology. δ13 CRing reconstructions are based on a solid knowledge of isotope fractionations during formation of primary photosynthates (δ13 CP ), such as sucrose. However, δ13 CRing is not merely a record of δ13 CP . Isotope fractionation processes, which are not yet fully understood, modify δ13 CP during sucrose transport. We traced, how the environmental intra-seasonal δ13 CP signal changes from leaves to phloem, tree-ring and roots, for 7 year old Pinus sylvestris, using δ13 C analysis of individual carbohydrates, δ13 CRing laser ablation, leaf gas exchange and enzyme activity measurements. The intra-seasonal δ13 CP dynamics was clearly reflected by δ13 CRing , suggesting negligible impact of reserve use on δ13 CRing . However, δ13 CP became increasingly 13 C-enriched during down-stem transport, probably due to post-photosynthetic fractionations such as sink organ catabolism. In contrast, δ13 C of water-soluble carbohydrates, analysed for the same extracts, did not reflect the same isotope dynamics and fractionations as δ13 CP , but recorded intra-seasonal δ13 CP variability. The impact of environmental signals on δ13 CRing , and the 0.5 and 1.7‰ depletion in photosynthates compared ring organic matter and tree-ring cellulose, respectively, are useful pieces of information for studies exploiting δ13 CRing .


Assuntos
Terapia a Laser , Pinus sylvestris , Pinus , Árvores/metabolismo , Pinus sylvestris/metabolismo , Estações do Ano , Isótopos de Carbono/análise , Carboidratos/análise , Folhas de Planta/metabolismo , Sacarose/metabolismo , Pinus/metabolismo
3.
Front Behav Neurosci ; 16: 950093, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36035019

RESUMO

Background: Older individuals have been reported to suffer from cognitive disorders after surgery. Various types of surgical trauma have been used to establish postoperative cognitive dysfunction (POCD) animal models in preclinical studies. However, few comparative analyses of these animal models were conducted. Methods: Tibial surgery, abdominal surgery, and extended abdominal surgery were performed on aged ICR mice to establish POCD models. Behavioral tests included open field, novel object recognition, fear conditioning, and Morris water maze tests. The Z-score methodology was adopted to obtain a comprehensive and integrated memory performance profile. The changes in hippocampal neuroinflammation were analyzed by ELISA, PCR, and immunofluorescence. Results: In this study, we found that each type of non-cardiac surgical trauma has a different effects on locomotor activity. Tibial and extended abdominal surgeries led to more significant cognitive impairment than abdominal surgery. Inflammatory cytokines peaked on postoperative day 1 and decreased to control levels on days 3 and 7. Hippocampal neuroinflammation indicators between the three surgery types on postoperative day 1 had no statistical differences. Conclusion: Overall, the type and intensity of non-cardiac surgical trauma can affect cognitive behavioral outcomes and central inflammation. The shortcomings and emerging issues of POCD animal research methods need to be further studied and solved.

4.
J Agric Food Chem ; 69(14): 4243-4252, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33821640

RESUMO

Tyrosinase is a key enzyme responsible for enzymatic browning of fruits and vegetables and skin disorders due to overproduction of melanin. Arbutin is an inhibitor of tyrosinase; however, its high polarity and weak transdermal absorption capacity limit its applications. In this paper, a green solvent system was developed to successfully synthesize arbutin esters with improved liposolubilities (Clog P values = 0.27-5.03). Among the obtained esters, arbutin undecenoate (AU) showed the strongest tyrosinase-inhibiting activity (15.6%), which was 9.0 times higher than that of arbutin. An enzyme kinetics study indicated that AU was a competitive inhibitor with reversible inhibition. The esters inhibited tyrosinase by making the secondary structure of tyrosinase looser and less stable; moreover, the interactions between tyrosinase and AU driven by metal interactions and hydrogen bonds also offered a mechanism for inhibition of AU on tyrosinase. In addition, AU (100 µM) reduced the melanin content of B16 mouse melanoma cells to 61.3% of the control group.


Assuntos
Arbutina , Ésteres , Animais , Arbutina/farmacologia , Catálise , Melaninas , Camundongos , Monofenol Mono-Oxigenase
5.
Front Med (Lausanne) ; 8: 604221, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33665196

RESUMO

Background: Cancer patients may carry a worse prognosis with SARS-CoV-2 infection. Most of the previous studies described the outcomes of hospitalized cancer patients. We aimed to study the clinical factors differentiating patients requiring hospital care vs. home recovery, and the trajectory of their anti-cancer treatment. Methods: This study was conducted in a community cancer center in New York City. Eligible patients were those who had cancer history and were diagnosed of SARS-CoV-2 infection between March 1 and May 30, 2020, with confirmatory SARs-CoV-2 virus test or antibody test. Four groups were constructed: (A) hospitalized and survived, (B) hospitalized requiring intubation and/or deceased, (C) non-hospitalized, asymptomatic, with suspicious CT image findings, close exposure, or positive antibody test, and (D) non-hospitalized and symptomatic. Results: One hundred and six patients were included in the analysis. Thirty-five patients (33.0%) required hospitalization and 13 (12.3%) died. Thirty (28.3%) patients were asymptomatic and 41 (38.7%) were symptomatic and recovered at home. Comparing to patients who recovered at home, hospitalized patients were composed of older patients (median age 71 vs. 63 years old, p = 0.000299), more who received negative impact treatment (62.9 vs. 32.4%, p = 0.0036) that mostly represented myelosuppressive chemotherapy (45.7 vs. 23.9%, p = 0.0275), and more patients with poorer baseline performance status (PS ≥ 2 25.7 vs. 2.8%, p = 0.0007). Hypoxemia (35% in group A vs. 73.3% in group B, p = 0.0271) at presentation was significant to predict mortality in hospitalized patients. The median cumulative hospital stay for discharged patients was 16 days (range 5-60). The median duration of persistent positivity of SARS-CoV-2 RNA was 28 days (range 10-86). About 52.9% of patients who survived hospitalization and required anti-cancer treatment reinitiated therapy. Ninety-two percent of the asymptomatic patients and 51.7% of the symptomatic patients who recovered at home continued treatment on schedule and almost all reinitiated treatment after recovery. Conclusions: Cancer patients may have a more severe status of SARS-CoV-2 infection after receiving myelosuppressive chemotherapy. Avoidance should be considered in older patients with poor performance status. More than two thirds of patients exhibit minimal to moderate symptoms, and many of them can continue or restart their anti-cancer treatment upon recovery.

6.
JCO Glob Oncol ; 6: 1298-1305, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32795196

RESUMO

PURPOSE: As a result of their immunocompromised status associated with disease and treatment, patients with cancer face a profound threat for higher rates of complications and mortality if they contract the coronavirus disease 2019 infection. Medical oncology communities have developed treatment modifications to balance the risk of contracting the virus with the benefit of improving cancer-related outcomes. METHODS: We systemically examined our community cancer center database to display patterns of change and to unveil factors that have been considered with each decision. We studied a cohort of 282 patients receiving treatment and found that 159 patients (56.4%) had treatment modifications. RESULTS: The incidence of treatment modification was observed in patients undergoing adjuvant and neoadjuvant (41.4%), palliative (62.9%), or injectable endocrine or bone-modulating only (76.0%) treatments. Modifications were applied to regimens with myelosuppressive (56.5%), immunosuppressive (69.2%), and immunomodulating (61.5%) potentials. These modifications also affected intravenous (54.9%) and subcutaneous injectable treatments (62.5%) more than oral treatments (15.8%). Treatment modifications in 112 patients (70.4%) were recommended by providers, and 47 (29.6%) were initiated by patients. The most common strategy of modification was to skip or postpone a scheduled treatment (49%). Among treatment with no modifications, treatment regimens were maintained in patients who tolerated treatment well (37.0%), in treatments with curative intent (22%), and in symptomatic patients who required treatment (14%). CONCLUSION: Our observation and analysis suggested that the primary goal of treatment modification was to decrease potential exposure. The pattern also reflected the negative impact of the pandemic on health care providers who initiated these changes. Providers have to consider individualized recommendations incorporating multiple factors, such as tolerance, potential toxicity, treatment nature and route, and disease severity.


Assuntos
Antineoplásicos/administração & dosagem , Betacoronavirus , Infecções por Coronavirus , Neoplasias/terapia , Pandemias , Pneumonia Viral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , COVID-19 , Centros Comunitários de Saúde , Feminino , Humanos , Masculino , Oncologia/normas , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasias/patologia , Cidade de Nova Iorque , Cuidados Paliativos/métodos , Aceitação pelo Paciente de Cuidados de Saúde , SARS-CoV-2
7.
Oncol Res Treat ; 43(10): 491-497, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756049

RESUMO

INTRODUCTION: Nasal extranodal natural killer (NK)/T cell lymphoma, nasal type (ENKTCL) is a high-grade Epstein-Barr virus (EBV)-associated malignancy with poor outcomes. There are few biomarkers for the accurate diagnosis and prognostic prediction of the disease. The aim of this study was to investigate the clinicopathological significance of prohibitin (PHB) expression in nasal ENKTCL. METHODS: The expression level of PHB was detected via immunohistochemical staining in 49 nasal ENKTCL tissues and age- and sex-matched controls of 30 nasal mucosa-reactive lymphoid hyperplasia (NRLH) tissues. The correlations between the PHB expression and clinicopathological features of patients with nasal ENKTCL were evaluated. RESULTS: The results indicated a significantly decreased expression of PHB in nasal ENKTCL tissues compared with in NRLH tissues. Low-level PHB expression was significantly associated with younger age and fever (p = 0.008 and 0.018, respectively). The Kaplan-Meier analysis showed that the cytoplasm expression level of PHB in nasal ENKTCL was inversely related to overall survival (p = 0.046). CONCLUSIONS: PHB may be a potential diagnostic marker and prognostic predictor of nasal ENKTCL.


Assuntos
Linfoma Extranodal de Células T-NK/metabolismo , Neoplasias Nasais/metabolismo , Proteínas Repressoras/metabolismo , Fatores Etários , Biomarcadores/metabolismo , Febre/epidemiologia , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Lactato Desidrogenases/sangue , Linfoma Extranodal de Células T-NK/mortalidade , Linfoma Extranodal de Células T-NK/patologia , Pessoa de Meia-Idade , Neoplasias Nasais/mortalidade , Neoplasias Nasais/patologia , Prognóstico , Proibitinas , Taxa de Sobrevida
8.
Plants (Basel) ; 9(4)2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32244298

RESUMO

Polyploidy in Rhododendron fortunei has great potential to improve its horticultural and commercial value, and to also meet market demands. In this study, a feasible method for polyploid induction in R. fortunei via colchicine treatment was established, and the obtained polyploid plants were identified and characterized. As a result, the stem bases of tissue-cultured plantlets treated with 0.1% colchicine for 24 h showed the highest polyploid induction with a rate of 36.67%. By flow cytometric analysis, 69 tetraploids and 29 octoploids were identified in the regenerated plants that were examined. Phenotypic analysis indicated that the leaves of tetraploid and octoploid plants were smaller, rounder and thicker with more abundant and longer epidermal hairs than those of diploids. Furthermore, the stomata of polyploids were larger and sparser than those of diploids. An increase in chlorophyll content was also detected in polyploids, which resulted in darker green leaves. In conclusion, our study established an effective method to induce polyploidy in R. fortunei, which could be used to develop new genetic resources for breeding R. fortunei and other Rhododendron species in the future.

9.
Cell Adh Migr ; 13(1): 236-248, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31240993

RESUMO

Our previous studies have demonstrated that XIAP promotes bladder cancer metastasis through upregulating RhoGDIß/MMP-2 pathway. However, the molecular mechanisms leading to the XIAP upregulation was unclear. In current studies, we found that XIAP was overexpressed in human high grade BCs, high metastatic human BCs, and in mouse invasive BCs. Mechanistic studies indicated that XIAP overexpression in the highly metastatic T24T cells was due to increased mRNA stability of XIAP that was mediated by downregulated miR-200c. Moreover, the downregulated miR-200c was due to CREB inactivation, while miR-200c downregulation reduced its binding to the 3'-UTR region of XIAP mRNA. Collectively, our results demonstrate the molecular basis leading to XIAP overexpression and its crucial role in BC invasion.


Assuntos
Neoplasias Pulmonares/secundário , MicroRNAs/genética , RNA Mensageiro/metabolismo , Neoplasias da Bexiga Urinária/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/biossíntese , Invasividade Neoplásica/genética , Neoplasias da Bexiga Urinária/patologia
10.
Food Funct ; 10(4): 1999-2009, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30900716

RESUMO

Chinese dark teas (CDTs) are a special type of tea traditionally consumed by ethnic minorities around the border regions of China. Dark tea produced by the Yao population of Guangxi could help prevent diarrhea following the heavy consumption of food. However, the underlying mechanisms behind this effect are not clear. This study aimed to investigate the function and underlying mechanisms of dark tea by examining the effects of different doses of dark tea on diarrhea in mice caused by Folium Sennae. It was found that dark tea could significantly improve the rate of loose stools and diarrhea index, and had an inhibitory effect on intestine peristalsis in high- and moderate-dose groups. Compared with green tea, significantly decreased levels of water extract, tea polyphenol and amino acid were found in dark tea, whereas the content of both caffeine and gallocatechin was increased. The result of dilution plating showed that Aspergillus niger and Byssochlamys fulva were consistent with microbial diversity as assessed by high-throughput sequencing technology. A total of 12 metabolites related to an anti-diarrhea effect were identified by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). These findings provide a physiological basis for developing dark tea produced by the Yao population of Guangxi as a drink that can regulate and improve the intestinal flora in humans.


Assuntos
Antidiarreicos/administração & dosagem , Bactérias/isolamento & purificação , Camellia sinensis/microbiologia , Diarreia/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Chá/microbiologia , Animais , Antidiarreicos/química , Bactérias/classificação , Bactérias/genética , Biodiversidade , Camellia sinensis/química , China , Cromatografia Líquida de Alta Pressão , Diarreia/fisiopatologia , Feminino , Humanos , Masculino , Peristaltismo/efeitos dos fármacos , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/microbiologia , Espectrometria de Massas em Tandem , Chá/química
11.
Exp Hematol Oncol ; 6: 8, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28352491

RESUMO

BACKGROUND: Acquired factor VIII (FVIII) deficiency, or acquired hemophilia A (AHA), is a rare autoimmune disorder involving antibody-mediated depletion of coagulation FVIII, leading to severe, life-threatening bleeding. The condition is often associated with other autoimmune disorders, and its treatment involves replacement of FVIII and various modes of immunosuppression. Recently, a few noteworthy therapeutic advances have been made. We present two cases of severe AHA in Chinese women. One of these women developed this disorder in the setting of possible parvovirus B19 infection, which has not yet been reported in association with AHA. Other notable features of her case included paradoxical venous thrombosis and possible association with Sjogren's syndrome and myositis. The other woman failed to respond to usual first-line therapies despite exhibiting a less severe clinical course, illustrating the varied but potentially stubborn behavior of this disorder. CASE 1: An 87-year-old woman presented with diffuse ecchymoses, melena, vaginal bleeding. Labs showed hemoglobin (Hgb) nadir of 5.7 mg/dL, elevated partial thromboplastin time (PTT), FVIII level <1%, mixing study consistent with an inhibitor, elevated anti-Sjogren's-Syndrome-related antigen A antibody, elevated creatinine kinase, and elevated parvovirus IgM and IgG. Imaging of her arm showed diffuse myositis and deep venous thrombosis. After intravenous and oral steroids, her FVIII levels normalized, and her symptoms subsided. CASE 2: A 59-year-old woman presented with recurrent ecchymoses and hematomas in her extremities. Labs showed Hgb of 11.7 mg/dL, elevated PTT, FVIII level of 3%, and mixing study consistent with an inhibitor. Despite receiving a long course of steroids, several courses of IVIG, and a few courses of Rituximab, her FVIII level remained critically low. CONCLUSION: The rarity of AHA limits our understanding of this disease and the ability to perform trials to discover optimal therapies. We hope that these case reports and discussion will shed further light on the varied clinical manifestations and natural histories of this disorder to guide better recognition and treatment of AHA.

12.
Oncotarget ; 7(17): 23947-60, 2016 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-26992222

RESUMO

The conversion of precancerous lesions to full-fledged cancers requires the affected cells to surpass certain rate-limiting steps. We recently showed that activation of HRAS proto-oncogene in urothelial cells of transgenic mice causes simple urothelial hyperplasia (SUH) which is persistent and whose transition to low-grade papillary urothelial carcinoma (UC) must undergo nodular urothelial hyperplasia (NUH). We hypothesized that NUH, which has acquired fibrovascular cores, plays critical roles in mesenchymal-to-epithelial signaling, breaching the barriers of urothelial tumor initiation. Using proteomics involving two-dimensional gel electrophoresis, immunoblotting with pan-phosphotyrosine antibody and MALDI-mass spectrometry, we identified isoform 2 of pyruvate kinase (PKM2) as the major tyrosine-phosphorylated protein switched on during NUH. We extended this finding using specimens from transgenic mice, human UC and UC cell lines, establishing that PKM2, but not its spliced variant PKM1, was over-expressed in low-grade and, more prominently, high-grade UC. In muscle-invasive UC, PKM2 was co-localized with cytokeratins 5 and 14, UC progenitor markers. Specific inhibition of PKM2 by siRNA or shRNA suppressed UC cell proliferation via increased apoptosis, autophagy and unfolded protein response. These results strongly suggest that PKM2 plays an important role in the genesis of low-grade non-invasive and high-grade invasive urothelial carcinomas.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Papilar/patologia , Proteínas de Transporte/metabolismo , Transformação Celular Neoplásica/patologia , Proteínas de Membrana/metabolismo , Hormônios Tireóideos/metabolismo , Neoplasias da Bexiga Urinária/patologia , Uroplaquina II/fisiologia , Animais , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Papilar/genética , Carcinoma Papilar/metabolismo , Proteínas de Transporte/genética , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Humanos , Proteínas de Membrana/genética , Camundongos , Camundongos Transgênicos , Invasividade Neoplásica , Isoformas de Proteínas , Proto-Oncogene Mas , Hormônios Tireóideos/genética , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Proteínas de Ligação a Hormônio da Tireoide
13.
Am J Physiol Renal Physiol ; 299(3): F469-78, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20591941

RESUMO

Mammalian urine contains a range of macromolecule proteins that play critical roles in renal stone formation, among which Tamm-Horsfall protein (THP) is by far the most abundant. While THP is a potent inhibitor of crystal aggregation in vitro and its ablation in vivo predisposes one of the two existing mouse models to spontaneous intrarenal calcium crystallization, key controversies remain regarding the role of THP in nephrolithiasis. By carrying out a long-range follow-up of more than 250 THP-null mice and their wild-type controls, we demonstrate here that renal calcification is a highly consistent phenotype of the THP-null mice that is age and partially gene dosage dependent, but is gender and genetic background independent. Renal calcification in THP-null mice is progressive, and by 15 mo over 85% of all the THP-null mice develop spontaneous intrarenal crystals. The crystals consist primarily of calcium phosphate in the form of hydroxyapatite, are located more frequently in the interstitial space of the renal papillae than intratubularly, particularly in older animals, and lack accompanying inflammatory cell infiltration. The interstitial deposits of hydroxyapatite observed in THP-null mice bear strong resemblances to the renal crystals found in human kidneys bearing idiopathic calcium oxalate stones. Compared with 24-h urine from the wild-type mice, that of THP-null mice is supersaturated with brushite (calcium phosphate), a stone precursor, and has reduced urinary excretion of citrate, a stone inhibitor. While less frequent than renal calcinosis, renal pelvic and ureteral stones and hydronephrosis occur in the aged THP-null mice. These results provide direct in vivo evidence indicating that normal THP plays an important role in defending the urinary system against calcification and suggest that reduced expression and/or decreased function of THP could contribute to nephrolithiasis.


Assuntos
Calcinose/fisiopatologia , Medula Renal/fisiopatologia , Mucoproteínas/deficiência , Nefrolitíase/genética , Cálculos Ureterais/fisiopatologia , Animais , Calcinose/patologia , Cristalização , Modelos Animais de Doenças , Progressão da Doença , Feminino , Medula Renal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mucoproteínas/genética , Mutação , Nefrolitíase/fisiopatologia , Fenótipo , Cálculos Ureterais/patologia , Uromodulina
14.
Am J Physiol Renal Physiol ; 299(2): F387-95, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20427471

RESUMO

Urothelium that lines almost the entire urinary tract performs important functions and is prone to assaults by urinary microbials, metabolites, and carcinogens. To improve our understanding of urothelial physiology and disease pathogenesis, we sought to develop two novel transgenic systems, one that would allow inducible and urothelium-specific gene expression, and another that would allow inducible and urothelium-specific knockout. Toward this end, we combined the ability of the mouse uroplakin II promoter (mUPII) to drive urothelium-specific gene expression with a versatile tetracycline-mediated inducible system. We found that, when constructed under the control of mUPII, only a modified, reverse tetracycline trans-activator (rtTA-M2), but not its original version (rtTA), could efficiently trans-activate reporter gene expression in mouse urothelium on doxycycline (Dox) induction. The mUPII/rtTA-M2-inducible system retained its strict urothelial specificity, had no background activity in the absence of Dox, and responded rapidly to Dox administration. Using a reporter gene whose expression was secondarily controlled by histone remodeling, we were able to identify, colocalize with 5-bromo-2-deoxyuridine incorporation, and semiquantify newly divided urothelial cells. Finally, we established that, when combined with a Cre recombinase under the control of the tetracycline operon, the mUPII-driven rtTA-M2 could inducibly inactivate any gene of interest in mouse urothelium. The establishment of these two new transgenic mouse systems enables the manipulation of gene expression and/or inactivation in adult mouse urothelium at any given time, thus minimizing potential compensatory effects due to gene overexpression or loss and allowing more accurate modeling of urothelial diseases than previously reported constitutive systems.


Assuntos
Doxiciclina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Inativação de Genes , RNA Mensageiro/biossíntese , Urotélio/efeitos dos fármacos , Animais , Linhagem Celular , Proliferação de Células , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Estudos de Viabilidade , Genes Reporter , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Histonas/metabolismo , Integrases/genética , Óperon Lac , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Regiões Promotoras Genéticas , Protaminas/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Uroplaquina II , Urotélio/metabolismo
15.
Cancer Res ; 69(24): 9413-21, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19951992

RESUMO

Defects in pRb tumor suppressor pathway occur in approximately 50% of the deadly muscle-invasive urothelial carcinomas in humans and urothelial carcinoma is the most prevalent epithelial cancer in long-term survivors of hereditary retinoblastomas caused by loss-of-function RB1 mutations. Here, we show that conditional inactivation of both RB1 alleles in mouse urothelium failed to accelerate urothelial proliferation. Instead, it profoundly activated the p53 pathway, leading to extensive apoptosis, and selectively induced pRb family member p107. Thus, pRb loss triggered multiple fail-safe mechanisms whereby urothelial cells evade tumorigenesis. Additional loss of p53 in pRb-deficient urothelial cells removed these p53-dependent tumor barriers, resulting in late-onset hyperplasia, umbrella cell nuclear atypia, and rare-occurring low-grade, superficial papillary bladder tumors, without eliciting invasive carcinomas. Importantly, mice deficient in both pRb and p53, but not those deficient in either protein alone, were highly susceptible to subthreshold carcinogen exposure and developed invasive urothelial carcinomas that strongly resembled the human counterparts. The invasive lesions had a marked reduction of p107 but not p130 of the pRb family. Our data provide compelling evidence, indicating that urothelium, one of the slowest cycling epithelia, is remarkably resistant to transformation by pRb or p53 deficiency; that concurrent loss of these two tumor suppressors is necessary but insufficient to initiate urothelial tumorigenesis along the invasive pathway; that p107 may play a critical role in suppressing invasive urothelial tumor formation; and that replacing/restoring the function of pRb, p107, or p53 could be explored as a potential therapeutic strategy to block urothelial tumor progression.


Assuntos
Proteína do Retinoblastoma/deficiência , Proteína Supressora de Tumor p53/deficiência , Neoplasias da Bexiga Urinária/metabolismo , Animais , Processos de Crescimento Celular/fisiologia , Regulação para Baixo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Proteína do Retinoblastoma/genética , Proteína p107 Retinoblastoma-Like/metabolismo , Proteína Supressora de Tumor p53/genética , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/genética , Urotélio/metabolismo , Urotélio/patologia
16.
Artigo em Chinês | MEDLINE | ID: mdl-19670616

RESUMO

OBJECTIVE: To study the clinical effect of Treatment of blow-out fracture of medial orbital wall with nasoseptal cartilage under nasal endoscope. METHOD: Under a nasal endoscope, the fracture and the prolapsed orbital contents were reduced to the orbit, and then an autogenous nasoseptal cartilage was grafted into the orbital defect. The variations in the visual acuity, diplopia, enophthalmos degree and eyeball position were detected preoperatively and postoperatively. RESULT: During the follow up of three months to four years after operation, all the 28 cases showed neither loss nor distinct descent of visual acuity. The postoperative mean enophthalmos degree (1.5 +/- 0.6) mm was lower than the preoperation one(3.6 +/- 1.1) mm (P<0.05). Diplopia disappeared completely of 25 cases during 3 month after operation,while it appeared in the primary position of 2 cases. The eye movement was normal of 26 cases after operation t, and the abduction was slightly limited of 2 cases, but which was better than be for). Any displacement of filling material, infection, rejection reaction were not found of all the 28 cases. CONCLUSION: The medial orbital blow out fracture with nasal endoscope has many advantages, such as short operative route, clear surgical visual field, simple performance, light injury and no scars, and the effect of which will be really certain in the operative practice.


Assuntos
Septo Nasal/cirurgia , Fraturas Orbitárias/cirurgia , Adulto , Endoscopia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
17.
Am J Physiol Renal Physiol ; 293(6): F1935-43, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17898038

RESUMO

Although often supersaturated with mineral salts such as calcium phosphate and calcium oxalate, normal urine possesses an innate ability to keep them from forming harmful crystals. This inhibitory activity has been attributed to the presence of urinary macromolecules, although controversies abound regarding their role, or lack thereof, in preventing renal mineralization. Here, we show that 10% of the mice lacking osteopontin (OPN) and 14.3% of the mice lacking Tamm-Horsfall protein (THP) spontaneously form interstitial deposits of calcium phosphate within the renal papillae, events never seen in wild-type mice. Lack of both proteins causes renal crystallization in 39.3% of the double-null mice. Urinalysis revealed elevated concentrations of urine phosphorus and brushite (calcium phosphate) supersaturation in THP-null and OPN/THP-double null mice, suggesting that impaired phosphorus handling may be linked to interstitial papillary calcinosis in THP- but not in OPN-null mice. In contrast, experimentally induced hyperoxaluria provokes widespread intratubular calcium oxalate crystallization and stone formation in OPN/THP-double null mice, while completely sparing the wild-type controls. Whole urine from OPN-, THP-, or double-null mice all possessed a dramatically reduced ability to inhibit the adhesion of calcium oxalate monohydrate crystals to renal epithelial cells. These data establish OPN and THP as powerful and functionally synergistic inhibitors of calcium phosphate and calcium oxalate crystallization in vivo and suggest that defects in either molecule may contribute to renal calcinosis and stone formation, an exceedingly common condition that afflicts up to 12% males and 5% females.


Assuntos
Cálculos Renais/genética , Mucoproteínas/genética , Osteopontina/genética , Animais , Western Blotting , Cálcio/química , Oxalato de Cálcio/química , Oxalato de Cálcio/metabolismo , Fosfatos de Cálcio/química , Fosfatos de Cálcio/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Hiperoxalúria/urina , Cálculos Renais/patologia , Medula Renal/patologia , Camundongos , Camundongos Knockout , Espectroscopia de Infravermelho com Transformada de Fourier , Uromodulina
18.
Zhonghua Liu Xing Bing Xue Za Zhi ; 28(1): 37-41, 2007 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-17575929

RESUMO

OBJECTIVE: To explore the factors associated with retention in a community-based methadone maintenance treatment(MMT) among drug users in Urumqi. METHODS: With national MMT guideline( drift) for heroine addicted drug users, local heroine-dependent people were admitted to community-based MMT program affiliated to Xinjiang Uigur Autonomous Region Center for Mental Health. Data on outpatients' social-demo characteristics, baseline behaviors on drug use and daily stabilized dose of drugs were entered to MMT database. RESULTS: Up to 10, Feb. , 2006,353 persons withdrew MMT treatment among 709 heroin dependant drug users. Between 11, Aug., 2005 and 10, Feb., 2006, with median duration as 77 days, cumulative drop-out rate of 90 days and 180 days after first dose of MMT were 73.8% among 455 and 99.4% among 355 drug users, respectively. The incidence of drop-outs was 29.8 per 100 person-month. The median length of stay (days) in MMT was 68.0 (95% CI: 59.0- 78.0). Correlates of retention were found as: Being Uigur(HR = 1.35;95% CI :1.09-1.67), duration of drug use (HR =0.74; 95% CI:0.55-0.99) and stabilized dose(HR = 0.60;95% CI: 0.48-0.74) was found in multiple Cox proportional hazard regression model. CONCLUSION: Retention of MMT among drug users in Urumqi was low. Uigur people should be given individual counseling to help them increase the compliance rate. Within the ranges of clinic dosage, adjustment of the methadone dose on an individual base might serve as an appropriate approach to increase the effectiveness of the program.


Assuntos
Usuários de Drogas/estatística & dados numéricos , Dependência de Heroína/reabilitação , Cooperação do Paciente , Centros de Tratamento de Abuso de Substâncias/estatística & dados numéricos , Adulto , Idoso , China , Usuários de Drogas/psicologia , Feminino , Dependência de Heroína/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
J Clin Invest ; 117(2): 314-25, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17256055

RESUMO

Although ras is a potent mitogenic oncogene, its tumorigenicity depends on cellular context and cooperative events. Here we show that low-level expression of a constitutively active Ha-ras in mouse urothelium induces simple urothelial hyperplasia that is resistant to progression to full-fledged bladder tumors even in the absence of Ink4a/Arf. In stark contrast, doubling of the gene dosage of the activated Ha-ras triggered early-onset, rapidly growing, and 100% penetrant tumors throughout the urinary tract. Tumor initiation required superseding a rate-limiting step between simple and nodular hyperplasia, the latter of which is marked by the emergence of mesenchymal components and the coactivation of AKT and STAT pathways as well as PTEN inactivation. These results indicate that overactivation of Ha-ras is both necessary and sufficient to induce bladder tumors along a low-grade, noninvasive papillary pathway, and they shed light on the recent findings that ras activation, via point mutation, overexpression, or intensified signaling from FGF receptor 3, occurs in 70%-90% of these tumors in humans. Our results highlight the critical importance of the dosage/strength of Ha-ras activation in dictating its tumorigenicity--a mechanism of oncogene activation not fully appreciated to date. Finally, our results have clinical implications, as inhibiting ras and/or its downstream effectors, such as AKT and STAT3/5, could provide alternative means to treat low-grade, superficial papillary bladder tumors, the most common tumor in the urinary system.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/deficiência , Inibidor p16 de Quinase Dependente de Ciclina/genética , Genes ras , Neoplasias da Bexiga Urinária/etiologia , Neoplasias da Bexiga Urinária/genética , Animais , Sequência de Bases , Senescência Celular , Primers do DNA/genética , Dosagem de Genes , Regulação da Expressão Gênica , Genes p16 , Genótipo , Humanos , Hiperplasia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Modelos Biológicos , Fenótipo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Coelhos , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia , Urotélio/metabolismo , Urotélio/patologia
20.
Am J Physiol Renal Physiol ; 289(3): F562-8, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15840768

RESUMO

Urothelium that lines almost the entire urinary tract acts as a permeability barrier and is involved in the pathogenesis of major urinary diseases, including urothelial carcinoma, urinary tract infection, and interstitial cystitis. However, investigation of urothelial biology and diseases has been hampered by the lack of tissue-specific approaches. To address this deficiency, we sought to develop a urothelium-specific knockout system using the Cre/loxP strategy. Transgenic mouse lines were generated in which a 3.6-kb mouse uroplakin II (UPII) promoter was used to drive the expression of Cre recombinase (Cre). Among the multiple tissues analyzed, Cre was found to be expressed exclusively in the urothelia of the transgenic mice. Crossing a UPII-Cre transgenic line with a ROSA26-LacZ reporter line, in which LacZ expression depends on Cre-mediated deletion of a floxed "stop" sequence, led to LacZ expression only in the urothelium. Gene recombination was also observed when the UPII-Cre line was crossed to an independent line in which a part of the p53 gene was flanked by the loxP sequences (floxed p53). Truncation of the p53 gene and mRNA was observed exclusively in the urothelia of double transgenic mice harboring both the UPII-Cre transgene and the floxed p53 allele. These results demonstrate for the first time the feasibility and potentially wide applicability of the UPII-Cre transgenic mice to inactivate any genes of interest in the urothelium.


Assuntos
Deleção de Genes , Integrases/genética , Camundongos Knockout , Biologia Molecular/métodos , Urotélio/fisiologia , Animais , Regulação Enzimológica da Expressão Gênica , Integrases/metabolismo , Óperon Lac , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos , Camundongos Transgênicos , Regiões Promotoras Genéticas/genética , Uroplaquina II
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