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1.
J Formos Med Assoc ; 121(8): 1450-1457, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34836662

RESUMO

BACKGROUND/PURPOSE: Clarithromycin-based standard triple therapy is still commonly adopted by 81.4% of physicians in real-world practice but yields low eradication rates. Therefore, we conducted this study to compare the efficacy of gastric juice-guided therapy for first-line eradication with the standard triple therapy, in order to provide an alternative to real-world practice. METHODS: A total of 182 treatment-naïve Hp-infected patients were included and randomly allocated to either susceptibility-guided therapy (SGT) with gastric juice PCR or Clarithromycin-based standard triple therapy (STT) for 7 days. RESULTS: The intention-to-treat eradication rates were 89% (81/91) in SGT and 75.8% in STT (p < 0.031). The per-protocol eradication rates were 91.0% (81/89) in SGT and 79.3% (69/87) in STT (p < 0.034). Among the subgroups of different antibiotic resistance, patients with SGT demonstrated superior eradication rates (91.7% vs 45.5%, p < 0.027) in the subgroup of both clarithromycin resistance and levofloxacin resistance. CONCLUSION: This prospective randomized controlled trial demonstrated the reliable efficacy of susceptibility-guided therapy via gastric juice PCR for the first-line Hp eradication. In Asia-Pacific area, where standard triple therapy is still adopted by the majority of the physicians, it is a recommended alternative to overcome the increasing antibiotic resistance.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Claritromicina/uso terapêutico , Quimioterapia Combinada , Suco Gástrico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/genética , Humanos , Reação em Cadeia da Polimerase , Estudos Prospectivos , Inibidores da Bomba de Prótons/uso terapêutico
2.
Life (Basel) ; 11(12)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34947850

RESUMO

Colorectal cancer (CRC) is one of the most common cancers worldwide and its incidence is increasing; therefore, an understanding of its oncogenic mechanisms is critical for improving its treatment and management. Methylglyoxal (MGO) has a highly reactive aldehyde group and has been suggested to play a role in oncogenesis. However, no standardized data are currently available on MGO levels in colorectal precancerous and cancerous lesions. We collected 40 matched colorectal tumor and peritumor tissues from patients with low-grade dysplasia (LGD), high-grade dysplasia (HGD), and invasive cancer (IC). MGO levels increased between LGD, HGD, and IC tumor tissues (215.25 ± 39.69, 267.45 ± 100.61, and 587.36 ± 123.19 µg/g protein, respectively; p = 0.014). The MGO levels in peritumor tissue increased and were significantly higher than MGO levels in tumor tissue (197.99 ± 49.40, 738.09 ± 247.87, 933.41 ± 164.83 µg/g protein, respectively; p = 0.002). Tumor tissue MGO levels did not correlate with age, sex, underlying disease, or smoking status. These results suggest that MGO levels fluctuate in progression of CRC and warrants further research into its underlying mechanisms and function in tumor biology.

3.
Sensors (Basel) ; 21(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202597

RESUMO

BACKGROUND: Feature extraction from photoplethysmography (PPG) signals is an essential step to analyze vascular and hemodynamic information. Different morphologies of PPG waveforms from different measurement sites appear. Various phenomena of missing or ambiguous features exist, which limit subsequent signal processing. METHODS: The reasons that cause missing or ambiguous features of finger and wrist PPG pulses are analyzed based on the concept of component waves from pulse decomposition. Then, a systematic approach for missing-feature imputation and ambiguous-feature resolution is proposed. RESULTS: From the experimental results, with the imputation and ambiguity resolution technique, features from 35,036 (98.7%) of 35,502 finger PPG cycles and 36307 (99.1%) of 36,652 wrist PPG cycles can be successfully identified. The extracted features became more stable and the standard deviations of their distributions were reduced. Furthermore, significant correlations up to 0.92 were shown between the finger and wrist PPG waveforms regarding the positions and widths of the third to fifth component waves. CONCLUSION: The proposed missing-feature imputation and ambiguous-feature resolution solve the problems encountered during PPG feature extraction and expand the feature availability for further processing. More intrinsic properties of finger and wrist PPG are revealed. The coherence between the finger and wrist PPG waveforms enhances the applicability of the wrist PPG.


Assuntos
Fotopletismografia , Punho , Dedos , Frequência Cardíaca , Processamento de Sinais Assistido por Computador
4.
Polymers (Basel) ; 13(4)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670799

RESUMO

Mesoporous bioactive glass (MBG) has a high specific surface area, promoting the reaction area, thereby improving the bioactivity; thus, MBG is currently gaining popularity in the biomaterial field. Spray pyrolysis (SP) is a one-pot process that has the advantages of shorter process time and better particle bioactivity, therefore, MBG was prepared by SP process with various polyethylene glycol (PEG, molecular weight ranged from 2000-12,000) and acid (HCl and CH3COOH) additions. In vitro bioactivity and mesoporous properties of the so-obtained MBG were investigated. The experimental results showed that all the MBG exhibited amorphous and mesoporous structure. Increasing the molecular weight of PEG can improve the mesoporous structure and bioactivity of MBG. Whereas optimized MBG was prepared with suitable concentration of PEG and CH3COOH. In the present work, MBG synthesized via spray pyrolysis by adding 5 g of PEG with a molecular weight of 12,000 and 50 mL of CH3COOH exhibited the best in vitro bioactivity and mesoporous structure.

5.
Proc Natl Acad Sci U S A ; 118(10)2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33653947

RESUMO

Pancreatic ductal adenocarcinoma (PDA) is a lethal, therapy-resistant cancer that thrives in a highly desmoplastic, nutrient-deprived microenvironment. Several studies investigated the effects of depriving PDA of either glucose or glutamine alone. However, the consequences on PDA growth and metabolism of limiting both preferred nutrients have remained largely unknown. Here, we report the selection for clonal human PDA cells that survive and adapt to limiting levels of both glucose and glutamine. We find that adapted clones exhibit increased growth in vitro and enhanced tumor-forming capacity in vivo. Mechanistically, adapted clones share common transcriptional and metabolic programs, including amino acid use for de novo glutamine and nucleotide synthesis. They also display enhanced mTORC1 activity that prevents the proteasomal degradation of glutamine synthetase (GS), the rate-limiting enzyme for glutamine synthesis. This phenotype is notably reversible, with PDA cells acquiring alterations in open chromatin upon adaptation. Silencing of GS suppresses the enhanced growth of adapted cells and mitigates tumor growth. These findings identify nongenetic adaptations to nutrient deprivation in PDA and highlight GS as a dependency that could be targeted therapeutically in pancreatic cancer patients.


Assuntos
Carcinoma Ductal Pancreático/metabolismo , Glutamato-Amônia Ligase/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/genética , Linhagem Celular Tumoral , Estabilidade Enzimática , Glutamato-Amônia Ligase/genética , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/genética
6.
Public Health Nurs ; 38(1): 77-84, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33270931

RESUMO

OBJECTIVE: This study was conducted to describe and examine the impact of medication intervention practices among African-American clients in two nurse-led community nursing centers (CNCs). METHODS: This study used a retrospective-descriptive design. Omaha System data from visits of 196 African-American adults living with chronic disease and having two or more CNC visits in which medication regimen was an identified problem and the main reason for the visit was analyzed. RESULTS: The sample had a mean age of 53.1 (6.67) and was primarily women (82%), uninsured, and with high school or less education. A total of 9,259 Medication regimen interventions were documented and implemented during 1,146 client CNC visits. A paired samples t test revealed statistically significant improvements in Knowledge (t = 2.434, p < .01). Behavior (t = 0.077, p = .94) and Status (t = 1.489, p = .14) remained unchanged, although the ratings trended toward improvement for each. CONCLUSION: This study provides evidence that the nursing center model of care does improve the knowledge of medications among African-American clients. The study also demonstrated the Omaha System's utility to evaluate the impact of nursing interventions in community settings.


Assuntos
Negro ou Afro-Americano , Enfermagem em Saúde Comunitária , Conhecimentos, Atitudes e Prática em Saúde , Preparações Farmacêuticas , Padrões de Prática em Enfermagem , Adulto , Negro ou Afro-Americano/educação , Negro ou Afro-Americano/estatística & dados numéricos , Enfermagem em Saúde Comunitária/organização & administração , Feminino , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Enfermagem , Pesquisa em Avaliação de Enfermagem , Estudos Retrospectivos
7.
PLoS One ; 15(10): e0241053, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33104740

RESUMO

The relationship between methylglyoxal (MGO) and D-lactate during saikosaponin C (SSC) treatment of mice with accelerated nephrotoxic serum (NTS) nephritis was investigated. NTS nephritis was induced by administration of anti-basement membrane antibodies to C57BL/6 mice and three dosages of SSC were administered for 14 days. Proteinuria, blood urea nitrogen, serum creatinine, renal histology, urinary MGO and d-lactate changes were examined. Compared to the NTS control group, the middle dosage (10 mg/kg/day) of SSC significantly alleviated the development of nephritis based on urine protein measurements (34.40 ± 6.85 vs. 17.33 ± 4.79 mg/day, p<0.05). Pathological observation of the glomerular basement membrane (GBM) revealed monocyte infiltration, hypertrophy, and crescents were alleviated, and injury scoring also showed improved efficacy for the middle dose of SSC during nephritis (7.92 ± 1.37 vs. 3.50 ± 1.14, p<0.05). Moreover, the significant decreases in urinary levels of MGO (24.71 ± 3.46 vs. 16.72 ± 2.36 µg/mg, p<0.05) and D-lactate (0.31 ± 0.04 vs. 0.23 ± 0.02 µmol/mg, p<0.05) were consistent with the biochemical and pathological examinations. This study demonstrates that MGO and D-lactate may reflect the extent of damage and the efficacy of SSC in NTS nephritis; further studies are required to enable clinical application.


Assuntos
Glomerulonefrite/tratamento farmacológico , Ácido Láctico/urina , Ácido Oleanólico/análogos & derivados , Aldeído Pirúvico/urina , Saponinas , Animais , Camundongos , Camundongos Endogâmicos C57BL , Ácido Oleanólico/administração & dosagem , Ácido Oleanólico/uso terapêutico , Saponinas/administração & dosagem , Saponinas/uso terapêutico
8.
PLoS One ; 15(7): e0235849, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32649695

RESUMO

Nephrotoxicity severely limits the chemotherapeutic efficacy of cisplatin (CDDP). Oxidative stress is associated with CDDP-induced acute kidney injury (AKI). Methylglyoxal (MG) forms advanced glycation end products that elevate oxidative stress. We aimed to explore the role of MG and its metabolite D-lactate and identify the proteins involved in CDDP-induced AKI. Six-week-old female BALB/c mice were intraperitoneally administered CDDP (5 mg/kg/day) for 3 or 5 days. Blood urea nitrogen (42.6 ± 7.4 vs. 18.3 ± 2.5; p < 0.05) and urinary N-acetyl-ß-D-glucosaminide (NAG; 4.89 ± 0.61 vs. 2.43 ± 0.31 U/L; p < 0.05) were significantly elevated in the CDDP 5-day group compared to control mice. Histological analysis confirmed AKI was successfully induced. Confocal microscopy revealed TNF-α was significantly increased in the CDDP 5-day group. Fluorogenic derivatized liquid chromatography-tandem mass spectrometry (FD-LC-MS/MS) showed the kidney MG (36.25 ± 1.68 vs. 18.95 ± 2.24 mg/g protein, p < 0.05) and D-lactate (1.78 ± 0.29 vs. 1.12 ± 0.06 mol/g protein, p < 0.05) contents were significantly higher in the CDDP 5-day group than control group. FD-LC-MS/MS proteomics identified 33 and nine altered peaks in the CDDP 3-day group and CDDP 5-day group (vs. control group); of the 35 proteins identified using the MOSCOT database, 11 were antioxidant-related. Western blotting confirmed that superoxide dismutase 1 (SOD-1) and parkinson disease protein 7 (DJ-1) are upregulated and may participate with MG in CDDP-induced AKI. This study demonstrates TNF-α, MG, SOD-1 and DJ-1 play crucial roles in CDDP-induced AKI.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Antineoplásicos/efeitos adversos , Cisplatino/efeitos adversos , Ácido Láctico/análise , Aldeído Pirúvico/análise , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Animais , Cromatografia Líquida , Feminino , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Ácido Láctico/metabolismo , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos , Aldeído Pirúvico/metabolismo , Espectrometria de Massas em Tandem
9.
J Clin Invest ; 130(10): 5197-5208, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32516134

RESUMO

The tight junction protein claudin-2 is upregulated in disease. Although many studies have linked intestinal barrier loss to local and systemic disease, these have relied on macromolecular probes. In vitro analyses show, however, that these probes cannot be accommodated by size- and charge-selective claudin-2 channels. We sought to define the impact of claudin-2 channels on disease. Transgenic claudin-2 overexpression or IL-13-induced claudin-2 upregulation increased intestinal small cation permeability in vivo. IL-13 did not, however, affect permeability in claudin-2-knockout mice. Claudin-2 is therefore necessary and sufficient to effect size- and charge-selective permeability increases in vivo. In chronic disease, T cell transfer colitis severity was augmented or diminished in claudin-2-transgenic or -knockout mice, respectively. We translated the in vitro observation that casein kinase-2 (CK2) inhibition blocks claudin-2 channel function to prevent acute, IL-13-induced, claudin-2-mediated permeability increases in vivo. In chronic immune-mediated colitis, CK2 inhibition attenuated progression in claudin-2-sufficient, but not claudin-2-knockout, mice, i.e., the effect was claudin-2 dependent. Paracellular flux mediated by claudin-2 channels can therefore promote immune-mediated colitis progression. Although the mechanisms by which claudin-2 channels intensify disease remain to be defined, these data suggest that claudin-2 may be an accessible target in immune-mediated disorders, including inflammatory bowel disease.


Assuntos
Claudinas/deficiência , Colite/etiologia , Animais , Claudinas/genética , Claudinas/metabolismo , Colite/imunologia , Colite/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Interleucina-13/administração & dosagem , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Regulação para Cima
10.
J Community Health Nurs ; 37(1): 35-46, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31905304

RESUMO

Integrating behavioral health services into nurse-led primary care at one location ensures that individuals receive a comprehensive array of preventive and restorative services, based on their varying needs. A formative program evaluation of a federally funded behavioral health integration (BHI) project in a small nurse-led clinic used the Omaha System taxonomy to explore the changes in the documented practice of providers due to the BHI implementation. The evaluation provided evidence of the benefits of a collaborative care model to urban low-income, underserved, adults who were predominantly African American/Blacks.


Assuntos
Enfermagem em Saúde Comunitária/organização & administração , Prestação Integrada de Cuidados de Saúde/organização & administração , Serviços de Saúde Mental/organização & administração , Enfermagem de Atenção Primária , Atenção Primária à Saúde/organização & administração , Adulto , Negro ou Afro-Americano , Feminino , Humanos , Masculino , Modelos de Enfermagem , Modelos Organizacionais , População Urbana
11.
Sci Rep ; 9(1): 15535, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664063

RESUMO

Gastroesophageal reflux disease (GERD) can cause several upper airway symptoms and alter the physiology of nasopharyngeal mucosa, while upper airway diseases in turn might also exacerbate GERD symptoms. For a long time, asthma was considered a risk factor of GERD in the literature. Asthma and allergic rhinitis (AR) are usually identified as united airway disease according to similar epidemiology and pathophysiology; however, the association between AR and GERD is less elucidated. We aimed to evaluate whether AR would increase the development of GERD. Patients diagnosed as AR were identified from the National Health Insurance Research Database between January 1, 2000 and December 31, 2005 without prior history of gastroesophageal reflux disease. The outcome of interest was new-onset GERD. Cox regression models were applied to calculate the hazard ratio (HR) of GERD. We analyzed the data of 193,810 AR patients aged 18 years or older and being free of AR at baseline. The AR cohort (n = 96,905) had a significantly increased risk of GERD over a non-AR cohort (n = 96905) (adjusted HR (aHR) 1.94; 95% CI = 1.88-1.99, p < 0.001). AR may have stronger correlation with GERD than does asthma, although asthma might increase GERD risk by means of certain pathways shared with AR.


Assuntos
Asma/epidemiologia , Bases de Dados Factuais , Refluxo Gastroesofágico , Modelos Biológicos , Rinite Alérgica , Adolescente , Adulto , Fatores Etários , Criança , Pré-Escolar , Feminino , Refluxo Gastroesofágico/epidemiologia , Refluxo Gastroesofágico/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Rinite Alérgica/complicações , Rinite Alérgica/epidemiologia , Fatores de Risco
12.
Helicobacter ; 24(2): e12568, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30821043

RESUMO

BACKGROUND: Culture of Helicobacter pylori with previous eradication failure has been emphasized in clinical guidelines. The current unmet need to manage previously treated H pylori is one tool with diagnostic accuracy and ability for antibiotics susceptibility. Gastric juice PCR can provide diagnosis and antibiotics susceptibility; however, whether treatment failure affects its accuracy remains uninvestigated. Our study aimed to investigate diagnostic accuracy and antibiotics susceptibility of juice PCR in previously treated H pylori and to compare with the current standard of culture. METHODS: We categorized all 547 patients into treatment-naïve, post-1st treatment, post-2nd treatment, and post-3rd treatment. Helicobacter pylori infection was confirmed using gold standards. Sensitivity, specificity, positive predictive value, negative predictive value, receiver operating characteristic (ROC) curve and area under ROC curve (AUC) of juice PCR and culture were calculated. Intra-gastric H pylori density was evaluated. Lastly, the antibiotics susceptibility results of gastric juice and culture were compared. RESULTS: Our findings demonstrated AUC was higher in juice PCR than culture in all patients (96.7% vs 91.3%, P < 0.0001). The superiority of juice PCR was statistically significant in previously treated patients (P < 0.0001) but not in treatment-naïve patients (P = 0.13). Antral H pylori density was less marked in previously treated patients (P = 0.014). The comparisons of PCR-RFLP and E-test for Clarithromycin resistance showed reliable AUC = 89.8%. CONCLUSION: Compared with the current standard of culture, the gastric juice PCR contains the strengths of performing the antibiotics susceptibility and overcomes the shortcomings of low accuracy. Consequently, gastric juice PCR suits the unmet need to manage previously treated H pylori.


Assuntos
Suco Gástrico/microbiologia , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Carga Bacteriana , Biópsia , Claritromicina/farmacologia , Claritromicina/uso terapêutico , Farmacorresistência Bacteriana , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Sensibilidade e Especificidade , Estômago/microbiologia , Falha de Tratamento
13.
Cell Mol Gastroenterol Hepatol ; 7(2): 255-274, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30686779

RESUMO

BACKGROUND & AIMS: Epithelial regeneration is essential for homeostasis and repair of the mucosal barrier. In the context of infectious and immune-mediated intestinal disease, interleukin (IL) 22 is thought to augment these processes. We sought to define the mechanisms by which IL22 promotes mucosal healing. METHODS: Intestinal stem cell cultures and mice were treated with recombinant IL22. Cell proliferation, death, and differentiation were assessed in vitro and in vivo by morphometric analysis, quantitative reverse transcriptase polymerase chain reaction, and immunohistochemistry. RESULTS: IL22 increased the size and number of proliferating cells within enteroids but decreased the total number of enteroids. Enteroid size increases required IL22-dependent up-regulation of the tight junction cation and water channel claudin-2, indicating that enteroid enlargement reflected paracellular flux-induced swelling. However, claudin-2 did not contribute to IL22-dependent enteroid loss, depletion of Lgr5+ stem cells, or increased epithelial proliferation. IL22 induced stem cell apoptosis but, conversely, enhanced proliferation within and expanded numbers of transit-amplifying cells. These changes were associated with reduced wnt and notch signaling, both in vitro and in vivo, as well as skewing of epithelial differentiation, with increases in Paneth cells and reduced numbers of enteroendocrine cells. CONCLUSIONS: IL22 promotes transit-amplifying cell proliferation but reduces Lgr5+ stem cell survival by inhibiting notch and wnt signaling. IL22 can therefore promote or inhibit mucosal repair, depending on whether effects on transit-amplifying or stem cells predominate. These data may explain why mucosal healing is difficult to achieve in some inflammatory bowel disease patients despite markedly elevated IL22 production.


Assuntos
Interleucinas/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Receptores Notch/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Claudina-2/metabolismo , Enterócitos/citologia , Enterócitos/efeitos dos fármacos , Enterócitos/metabolismo , Intestinos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Organoides/metabolismo , Células-Tronco/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Interleucina 22
15.
Proc Natl Acad Sci U S A ; 115(16): 4228-4233, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29610318

RESUMO

Non-small-cell lung cancer (NSCLC) is a leading cause of cancer death worldwide, with 25% of cases harboring oncogenic Kirsten rat sarcoma (KRAS). Although KRAS direct binding to and activation of PI3K is required for KRAS-driven lung tumorigenesis, the contribution of insulin receptor (IR) and insulin-like growth factor 1 receptor (IGF1R) in the context of mutant KRAS remains controversial. Here, we provide genetic evidence that lung-specific dual ablation of insulin receptor substrates 1/2 (Irs1/Irs2), which mediate insulin and IGF1 signaling, strongly suppresses tumor initiation and dramatically extends the survival of a mouse model of lung cancer with Kras activation and p53 loss. Mice with Irs1/Irs2 loss eventually succumb to tumor burden, with tumor cells displaying suppressed Akt activation and strikingly diminished intracellular levels of essential amino acids. Acute loss of IRS1/IRS2 or inhibition of IR/IGF1R in KRAS-mutant human NSCLC cells decreases the uptake and lowers the intracellular levels of amino acids, while enhancing basal autophagy and sensitivity to autophagy and proteasome inhibitors. These findings demonstrate that insulin/IGF1 signaling is required for KRAS-mutant lung cancer initiation, and identify decreased amino acid levels as a metabolic vulnerability in tumor cells with IR/IGF1R inhibition. Consequently, combinatorial targeting of IR/IGF1R with autophagy or proteasome inhibitors may represent an effective therapeutic strategy in KRAS-mutant NSCLC.


Assuntos
Carcinogênese/metabolismo , Carcinoma Pulmonar de Células não Pequenas/prevenção & controle , Genes ras , Proteínas Substratos do Receptor de Insulina/fisiologia , Fator de Crescimento Insulin-Like I/fisiologia , Insulina/farmacologia , Neoplasias Pulmonares/prevenção & controle , Proteínas Proto-Oncogênicas p21(ras)/fisiologia , Células A549 , Aminoácidos/metabolismo , Animais , Autofagia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Códon de Terminação , Humanos , Proteínas Substratos do Receptor de Insulina/deficiência , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/fisiopatologia , Camundongos , Proteínas de Neoplasias/fisiologia , Proteólise , Proteínas Proto-Oncogênicas c-akt/fisiologia , Transdução de Sinais/fisiologia
16.
Nat Commun ; 8(1): 242, 2017 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-28808255

RESUMO

Obesity is an established risk factor for pancreatic ductal adenocarcinoma (PDA). Despite recent identification of metabolic alterations in this lethal malignancy, the metabolic dependencies of obesity-associated PDA remain unknown. Here we show that obesity-driven PDA exhibits accelerated growth and a striking transcriptional enrichment for pathways regulating nitrogen metabolism. We find that the mitochondrial form of arginase (ARG2), which hydrolyzes arginine into ornithine and urea, is induced upon obesity, and silencing or loss of ARG2 markedly suppresses PDA. In vivo infusion of 15N-glutamine in obese mouse models of PDA demonstrates enhanced nitrogen flux into the urea cycle and infusion of 15N-arginine shows that Arg2 loss causes significant ammonia accumulation that results from the shunting of arginine catabolism into alternative nitrogen repositories. Furthermore, analysis of PDA patient tumors indicates that ARG2 levels correlate with body mass index (BMI). The specific dependency of PDA on ARG2 rather than the principal hepatic enzyme ARG1 opens a therapeutic window for obesity-associated pancreatic cancer.Obesity is an established risk factor for pancreatic ductal adenocarcinoma (PDA). Here the authors show that obesity induces the expression of the mitochondrial form of arginase ARG2 in PDA and that ARG2 silencing or loss results in ammonia accumulation and suppression of obesity-driven PDA tumor growth.


Assuntos
Carcinoma Ductal Pancreático/enzimologia , Mucoproteínas/metabolismo , Obesidade/complicações , Neoplasias Pancreáticas/enzimologia , Proteínas/metabolismo , Animais , Arginina/metabolismo , Carcinoma Ductal Pancreático/etiologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias/enzimologia , Mitocôndrias/metabolismo , Mucoproteínas/genética , Proteínas Oncogênicas , Ornitina/metabolismo , Neoplasias Pancreáticas/etiologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Proteínas/genética
17.
Cell Host Microbe ; 21(6): 671-681.e4, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28618266

RESUMO

Diarrhea is a host response to enteric pathogens, but its impact on pathogenesis remains poorly defined. By infecting mice with the attaching and effacing bacteria Citrobacter rodentium, we defined the mechanisms and contributions of diarrhea and intestinal barrier loss to host defense. Increased permeability occurred within 2 days of infection and coincided with IL-22-dependent upregulation of the epithelial tight junction protein claudin-2. Permeability increases were limited to small molecules, as expected for the paracellular water and Na+ channel formed by claudin-2. Relative to wild-type, claudin-2-deficient mice experienced severe disease, including increased mucosal colonization by C. rodentium, prolonged pathogen shedding, exaggerated cytokine responses, and greater tissue injury. Conversely, transgenic claudin-2 overexpression reduced disease severity. Chemically induced osmotic diarrhea reduced colitis severity and C. rodentium burden in claudin-2-deficient, but not transgenic, mice, demonstrating that claudin-2-mediated protection is the result of enhanced water efflux. Thus, IL-22-induced claudin-2 upregulation drives diarrhea and pathogen clearance.


Assuntos
Claudina-2/metabolismo , Diarreia/metabolismo , Infecções por Enterobacteriaceae/imunologia , Epitélio/metabolismo , Interleucinas/metabolismo , Mucosa Intestinal/metabolismo , Regulação para Cima , Animais , Permeabilidade da Membrana Celular , Citrobacter rodentium/imunologia , Citrobacter rodentium/patogenicidade , Colite/microbiologia , Citocinas/metabolismo , Diarreia/imunologia , Diarreia/microbiologia , Diarreia/patologia , Modelos Animais de Doenças , Infecções por Enterobacteriaceae/microbiologia , Epitélio/imunologia , Epitélio/microbiologia , Epitélio/patologia , Imunidade Inata/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Intestinos/microbiologia , Intestinos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Sódio/metabolismo , Junções Íntimas/metabolismo , Água/metabolismo , Interleucina 22
18.
Biomed Chromatogr ; 31(5)2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27741557

RESUMO

Lead (Pb) is an environmental pollutant associated with several diseases, such as nephrotoxicity. Methylglyoxal (MG) is a reactive dicarbonyl compound formed during glycolysis and reported to increase in kidney damage. Metformin is used as an MG scavenger in the clinic. In this study, we investigated the mechanism of Pb-induced renal injury and the effect of metformin on Pb-induced nephrotoxicity. Eighteen Wistar rats were randomly divided into three groups: control, Pb, and Pb + metformin groups. Pb (250 ppm) was administered in drinking water, and 50 mg/kg of metformin was co-administered orally. After 28 days, the levels of MG and its metabolite d-lactate in urine, serum and renal tissues were examined. The elevation of renal MG (56.86 ± 17.47 vs 36.40 ± 5.69, p < 0.01) and urinary d-lactate (0.68 ± 0.28 vs 0.32 ± 0.13, p < 0.01) was observed in Pb-exposed rats compared with those in control rats. After co-treatment with metformin, these phenomena were attenuated. In the present study, it was demonstrated for the first time that urinary d-lactate might serve as the candidate marker for Pb-induced nephrotoxicity in the clinic, and metformin might be a new therapeutic candidate for Pb poisoning.


Assuntos
Nefropatias/induzido quimicamente , Lactatos/metabolismo , Chumbo/toxicidade , Aldeído Pirúvico/metabolismo , Animais , Biomarcadores/análise , Biomarcadores/sangue , Biomarcadores/urina , Peso Corporal/efeitos dos fármacos , Creatinina/sangue , Creatinina/urina , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Nefropatias/metabolismo , Nefropatias/prevenção & controle , L-Lactato Desidrogenase/sangue , L-Lactato Desidrogenase/metabolismo , Lactatos/análise , Masculino , Metformina/administração & dosagem , Metformina/farmacologia , Aldeído Pirúvico/análise , Ratos Wistar , Ácido Úrico/sangue
19.
FEBS J ; 283(5): 899-911, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26744129

RESUMO

The virion host shutoff protein (vhs), encoded by the gene UL41, has RNase activity and is the key regulator of the early host shutoff response induced by type 1 herpes simplex virus. Despite low amino acid similarity, the vhs protein of the swine herpesvirus, pseudorabies virus (PrV), also exhibits RNase activity. However, the mechanism underlying the action of vhs remains undefined. Here, we report that the RNA degradation profile of PrV vhs is similar, but not identical, to that of type 1 herpes simplex virus vhs. Notably, the presence of a cap structure enhances both the degradation rate and the preferential targeting of the vhs protein towards the 3'-end of the encephalomyocarditis virus internal ribosome entry site (IRES). Furthermore, type 1 herpes simplex virus vhs produces a simple degradation pattern, but PrV vhs gives rise to multiple intermediates. The results of northern blotting using probes recognizing various regions of the RNA substrate found that PrV vhs also cleaves downstream of the IRES region and this vhs protein overall shows 5' to 3' RNase activity. Moreover, addition of the translation initiation factors eIF4H and eIF4B significantly increased the RNase activity of recombinant PrV vhs against capped RNA. Nonetheless, these proteins did not fully reconstitute the IRES-directed targeting pattern observed for vhs translated in a rabbit reticular lysate system. The interaction between PrV vhs and eIF4H/eIF4B implies that the translation initiation machinery within the cell is able to stimulate the nuclease activity of PrV vhs. However, this process remains inefficient in terms of the IRES-targeting pattern.


Assuntos
Herpesvirus Suídeo 1/química , Sítios Internos de Entrada Ribossomal , RNA Viral/química , Ribonucleases/metabolismo , Proteínas Virais/metabolismo , Vírion/química , Animais , Sequência de Bases , Fatores de Iniciação em Eucariotos/metabolismo , Deleção de Genes , Células HEK293 , Humanos , Dados de Sequência Molecular , Biossíntese de Proteínas , Coelhos , Proteínas Recombinantes/química , Transcrição Gênica
20.
IEEE Trans Biomed Circuits Syst ; 10(4): 864-873, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-28113440

RESUMO

Low-complexity compressed sensing (CS) techniques for monitoring electrocardiogram (ECG) signals in wireless body sensor network (WBSN) are presented. The prior probability of ECG sparsity in the wavelet domain is first exploited. Then, variable orthogonal multi-matching pursuit (vOMMP) algorithm that consists of two phases is proposed. In the first phase, orthogonal matching pursuit (OMP) algorithm is adopted to effectively augment the support set with reliable indices and in the second phase, the orthogonal multi-matching pursuit (OMMP) is employed to rescue the missing indices. The reconstruction performance is thus enhanced with the prior information and the vOMMP algorithm. Furthermore, the computation-intensive pseudo-inverse operation is simplified by the matrix-inversion-free (MIF) technique based on QR decomposition. The vOMMP-MIF CS decoder is then implemented in 90 nm CMOS technology. The QR decomposition is accomplished by two systolic arrays working in parallel. The implementation supports three settings for obtaining 40, 44, and 48 coefficients in the sparse vector. From the measurement result, the power consumption is 11.7 mW at 0.9 V and 12 MHz. Compared to prior chip implementations, our design shows good hardware efficiency and is suitable for low-energy applications.

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