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1.
J Photochem Photobiol B ; 223: 112287, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34454316

RESUMO

The rise in the antibiotic resistance rate of Helicobacter pylori has led to an increasing eradication failure of this carcinogenic bacterial pathogen worldwide. This underlines the need for alternative antibacterial strategies against H. pylori infection. Antimicrobial photodynamic therapy (aPDT) is a promising non-pharmacological antibacterial technology. In this study, the selective killing activities of three benzylidene cyclopentanone (BCP) photosensitizers (Y1, P1 and P3) towards H. pylori over normal human gastric epithelial GES-1 cells were evaluated and the ex vivo photodynamic inactivation effect was preliminarily assessed on twelve H. Pylor-infected mice. Results showed that under the irradiation of 24 J/cm2 532 nm laser, Y1, P1 and P3 at 2.5 µM induced a 3-log10 reduction of H. pylori CFU (99.9% killing). Confocal images showed that P3, unlike Y1 and P1, could not be uptaken by GES-1 cells. P3 at 2.5 to 20 µM showed not significant (p > 0.05) phototoxicity to GES-1 cells, nevertheless, Y1 and P1 under the same concentrations exhibited remarkable phototoxicity to GES-1 cells. In the co-culture of H. pylori and GES-1 cells, P3 at 2.5 µM led to a complete eradication of H. pylori under the irradiation of 24 J/cm2 532 nm laser. While for the GES-1 cells, no significant (p > 0.05) phototoxicity was observed under the same aPDT dosage. The ex vivo experiments showed that P3 mediated aPDT resulted in 82.4% to 100% reduction of H. pylori CFU without damaging the gastric mucosa. To sum up, P3 is a promising anti-H. pylori photosensitizer with the ability to selectively photo-inactivate H. pylori while sparing normal gastric tissues.


Assuntos
Ciclopentanos/química , Helicobacter pylori/efeitos dos fármacos , Lasers , Fármacos Fotossensibilizantes/farmacologia , Animais , Compostos de Benzilideno/química , Cátions/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Ciclopentanos/metabolismo , Ciclopentanos/farmacologia , Ciclopentanos/uso terapêutico , Modelos Animais de Doenças , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Mucosa Gástrica/efeitos da radiação , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/patologia , Helicobacter pylori/efeitos da radiação , Helicobacter pylori/ultraestrutura , Humanos , Camundongos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/metabolismo , Fármacos Fotossensibilizantes/uso terapêutico
2.
Clin Transl Gastroenterol ; 11(3): e00119, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32352709

RESUMO

Current conventional endoscopes have restricted the accuracy of treatment delivery and monitoring. Over the past decade, there have been major developments in nanotechnology and light triggered therapy, potentially allowing a better detection of challenging lesions and targeted treatment of malignancies in the gastrointestinal tract. Theranostics is a developing form of personalized medicine because it combines diagnosis and targeted treatment delivered in one step using advances in nanotechnology. This review describes the light-triggered therapies (including photodynamic, photothermal, and photoimmunotherapies), nanotechnological advances with nanopowder, nanostent, nanogels, and nanoparticles, enhancements brought to endoscopic ultrasound, in addition to experimental endoscopic techniques, combining both enhanced diagnoses and therapies, including a developed prototype of a "smart" multifunctional endoscope for localized colorectal cancer, near-infrared laser endoscope targeting the gastrointestinal stromal tumors, the concept of endocapsule for obscure gastrointestinal bleed, and a proof-of-concept therapeutic capsule using ultrasound-mediated targeted drug delivery. Hence, the following term has been proposed encompassing these technologies: "Theranostic gastrointestinal endoscopy." Future efforts for integration of these technologies into clinical practice would be directed toward translational and clinical trials translating into a more personalized and interdisciplinary diagnosis and treatment, shorter procedural time, higher precision, higher cost-effectiveness, and less need for repetitive procedures.


Assuntos
Endoscopia Gastrointestinal/métodos , Gastroenteropatias/terapia , Nanoestruturas/administração & dosagem , Fototerapia/métodos , Nanomedicina Teranóstica/métodos , Análise Custo-Benefício , Endoscopia Gastrointestinal/economia , Endoscopia Gastrointestinal/instrumentação , Endossonografia/instrumentação , Endossonografia/métodos , Mucosa Gástrica/diagnóstico por imagem , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/efeitos da radiação , Gastroenteropatias/diagnóstico , Gastroenteropatias/economia , Humanos , Mucosa Intestinal/diagnóstico por imagem , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos da radiação , Luz , Fototerapia/economia , Fototerapia/instrumentação , Nanomedicina Teranóstica/economia , Nanomedicina Teranóstica/instrumentação
3.
Cancer Prev Res (Phila) ; 13(3): 291-298, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32051178

RESUMO

Prior small reports have postulated a link between gastrointestinal polyposis and childhood and young adulthood cancer (CYAC) treatment (therapy-associated polyposis; TAP), but this remains a poorly understood phenomenon. The aim of this study was to describe the phenotypic spectrum of TAP in a multi-institutional cohort. TAP cases were identified from eight high-risk cancer centers. Cases were defined as patients with ≥10 gastrointestinal polyps without known causative germline alteration or hereditary colorectal cancer predisposition syndrome who had a history of prior treatment with chemotherapy and/or radiotherapy for CYAC. A total of 34 TAP cases were included (original CYAC: 27 Hodgkin lymphoma, three neuroblastoma, one acute myeloid leukemia, one medulloblastoma, one nephroblastoma, and one non-Hodgkin lymphoma). Gastrointestinal polyposis was first detected at a median of 27 years (interquartile range, 20-33) after CYAC treatment. A total of 12 of 34 (35%) TAP cases had ≥50 colorectal polyps. A total of 32 of 34 (94%) had >1 histologic polyp type. A total of 25 of 34 (74%) had clinical features suggestive of ≥1 colorectal cancer predisposition syndrome [e.g., attenuated familial adenomatous polyposis (FAP), serrated polyposis syndrome, extracolonic manifestations of FAP, mismatch repair-deficient colorectal cancer, or hamartomatous polyposis] including 8 of 34 (24%) with features of multiple such syndromes. TAP is an apparently acquired phenomenon that should be considered in patients who develop significant polyposis without known causative germline alteration but who have had prior treatment for a CYAC. Patients with TAP have features that may mimic various hereditary colorectal cancer syndromes, suggesting multiple concurrent biologic mechanisms, and recognition of this diagnosis may have implications for cancer risk and screening.


Assuntos
Sobreviventes de Câncer/estatística & dados numéricos , Polipose Intestinal/epidemiologia , Neoplasias/terapia , Gastropatias/epidemiologia , Adolescente , Fatores Etários , Antineoplásicos/efeitos adversos , Estudos de Coortes , Feminino , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Mucosa Gástrica/efeitos da radiação , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Mucosa Intestinal/efeitos da radiação , Polipose Intestinal/etiologia , Polipose Intestinal/patologia , Masculino , Neoplasias/mortalidade , Radioterapia/efeitos adversos , Gastropatias/etiologia , Gastropatias/patologia , Adulto Jovem
4.
Future Microbiol ; 14: 1199-1205, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31625444

RESUMO

Aim: The objective of this study was to investigate the possible synergy between doxycycline and photodynamic therapy against Helicobacter pylori and to evaluate the possible side effects on adenocarcinoma gastric cells with and without protoporphyrin IX. Materials & methods: Three H. pylori strains (ATCC 700392, 43504 and 49503) were grown on solid medium either with, or without, doxycycline at subinhibitory concentrations, and irradiated for 10, 20 and 30 minutes with a 400 nm-peaked light source. The phototoxicity tests on AGS cells were evaluated by MTT assay. Results: The photodynamic therapy and doxycycline combination showed an antibacterial synergistic effect with no significant toxicities. Conclusion: The synergistic treatment could be considered as an interesting therapeutic option.


Assuntos
Antibacterianos/farmacologia , Doxiciclina/farmacologia , Helicobacter pylori/efeitos dos fármacos , Fotoquimioterapia/métodos , Protoporfirinas/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Dermatite Fototóxica , Sinergismo Farmacológico , Mucosa Gástrica/citologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/efeitos da radiação , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/radioterapia , Humanos , Testes de Sensibilidade Microbiana , Fotoquimioterapia/efeitos adversos
5.
Esophagus ; 16(4): 402-407, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31222680

RESUMO

BACKGROUND: Definitive chemoradiotherapy is one of the treatment options for locally advanced esophageal cancer with curative intent. Esophagitis and pharyngitis are well-known adverse events that occur during chemoradiotherapy, but gastric mucosal injury has been less frequently reported compared to mucositis. Importantly, gastric mucosal injury is not well known, hard to manage, and sometimes fatal. Hence, we examined the clinical characteristics and the incidence of gastric mucosal injury after CRT for esophageal cancer. METHODS: The medical records of patients who received definitive chemoradiotherapy combined with 5-fluorouracil and cisplatin for stage II/III (nonT4) esophageal squamous cell carcinoma from January 2001 to December 2010 at our institute were reviewed retrospectively. RESULTS: We investigated 256 patients in whom, data for endoscopic abdomen examinations were both before and after CRT were available. Gastric mucosal damage was observed in 90 patients (35%) (grade 1/2/3 = 69/18/3). One of the possible risk factors identified in this study was the irradiation dose to abdomen. Compared to patients with cervical esophagus-upper thoracic esophagus tumor location, patients with middle thoracic esophagus-abdominal esophagus tumor location were more likely to develop gastric mucosal damage, although there was no statistically significant difference. CONCLUSIONS: It is important to consider gastric mucosal injury in patients who receive CRT, particularly when the irradiation field includes stomach.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia/efeitos adversos , Neoplasias Esofágicas/terapia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/efeitos da radiação , Hemorragia Gastrointestinal/etiologia , Lesões por Radiação/etiologia , Gastropatias/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/secundário , Cisplatino/administração & dosagem , Endoscopia Gastrointestinal , Neoplasias Esofágicas/patologia , Esôfago/patologia , Feminino , Fluoruracila/administração & dosagem , Mucosa Gástrica/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/diagnóstico por imagem , Fatores de Risco , Tomografia Computadorizada por Raios X
6.
J Gastrointest Cancer ; 50(4): 907-912, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30402826

RESUMO

PURPOSE: The optimal treatment for locally advanced GEJ and cardia adenocarcinoma is controversial. Several studies have shown that treating these patients with neoadjuvant chemoradiotherapy followed by surgery leads to survival benefits, and there are also studies that have declared conflicting results. It seems that there is still room for discussion. We calculated the survival rates and pathologic responses in our patients with characteristics which we mentioned above. METHODS: Patients with locally advanced, non-metastatic GEJ and cardia adenocarcinomas (only patients with Siewert's type I and II), who were referred to Imam Khomeini hospital (Institute of cancer) between 2005 and 2014 and received neoadjuvant chemoradiation and underwent surgery were enrolled in this retrospective cohort study. Evaluations were done every 3 months. RESULTS: Thirty-two patients enrolled in this study. Median follow up time was 23 months (Reverse Kaplan-Meier method). The rates of 1-year survival, 2-year survival, 3-year survival, 4-year survival, and 5-year survival were 75%, 52%, 52%, 37%, and 37%, respectively. No local recurrences occurred among patients; however, four patients experienced distal recurrence in the following locations: two cases (6.3%) in the liver, one case (3.1%) in the lung, and one case (3.1%) in the peritoneum. The rate of complete pathologic response (T0N0) was 21.9%. CONCLUSIONS: Neoadjuvant chemoradiation in patients with locally advanced GEJ and cardia adenocarcinoma will lead to a survival benefit.


Assuntos
Adenocarcinoma/terapia , Quimiorradioterapia/métodos , Neoplasias Esofágicas/terapia , Terapia Neoadjuvante/métodos , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Gástricas/terapia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cárdia/efeitos dos fármacos , Cárdia/patologia , Cárdia/efeitos da radiação , Cárdia/cirurgia , Intervalo Livre de Doença , Mucosa Esofágica/efeitos dos fármacos , Mucosa Esofágica/patologia , Mucosa Esofágica/efeitos da radiação , Mucosa Esofágica/cirurgia , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Esofagectomia , Junção Esofagogástrica/efeitos dos fármacos , Junção Esofagogástrica/patologia , Junção Esofagogástrica/efeitos da radiação , Junção Esofagogástrica/cirurgia , Feminino , Seguimentos , Gastrectomia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Mucosa Gástrica/efeitos da radiação , Mucosa Gástrica/cirurgia , Humanos , Irã (Geográfico)/epidemiologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Taxa de Sobrevida
7.
J Photochem Photobiol B ; 186: 107-115, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30029036

RESUMO

Since many years it has been acknowledged that some bacterial species, among which H. pylori, P. aeruginosa, P. acnes accumulate endogenous photosensitizers (PS) in the form of porphyrins. This makes antibacterial photodynamic therapy (PDT) easier to perform due to the possible avoidance of external PS. In this study, we focus on gastric infections associated with the presence of Helicobacter pylori (H. pylori), known to accumulate and release both protoporphyrin IX (PPIX) and coproporphyrins. PDT versus H. pylori can be carried out by modified endoscopes or by new ingestible luminous devices under development. In both cases of in vitro and in vivo applications, either for therapy (PDT) or diagnosis, scientific literature lacks studies on the possible side-effects of light treatments on the surrounding tissues. To this aim we evaluated in vitro side-effects due to a possible intrinsic photosensitivity of gastric mucosa or to a photosensitization by the PS released from the bacterium itself. Photo-toxicity studies were conducted on the AGS cell line (ATCC® CRL-1739™), commonly used as a model for the stomach mucosa tissue, considering PPIX as the photosensitizing agent. After first evaluations of PPIX dark toxicity, its uptake and accumulation sites, photo-toxicity tests were conducted using a LED light source peaked at 400 nm, by varying both PPIX concentration (50 nM - 2 µM) and light dose in the range 0.6-13 J/cm2, representing different treatment procedures found in literature. The oxidative stress consequent to irradiation was investigated both in terms of ROS production and assessment of the activity of enzymes involved in ROS-related biological mechanisms. A significant phototoxic effect was found only for PPIX concentration > 100 nM for all tested light doses. This indicates that the evaluated photo-treatments do not cause side effects even with the sensitization due to PPIX released by the bacteria.


Assuntos
Mucosa Gástrica/efeitos dos fármacos , Luz , Fármacos Fotossensibilizantes/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Mucosa Gástrica/efeitos da radiação , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/efeitos da radiação , Humanos , Microscopia Confocal , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Fotoquimioterapia/efeitos adversos , Fármacos Fotossensibilizantes/uso terapêutico , Protoporfirinas/metabolismo , Protoporfirinas/farmacologia , Protoporfirinas/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo
8.
Mol Med Rep ; 18(2): 1571-1581, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29901205

RESUMO

In the present study, the effects and underlying mechanism of RbAp48 on the radiosensitivity of AGS gastric cancer cells was investigated. Cell proliferation was determined with an MTT assay. Flow cytometry was performed to evaluate the cell cycle and apoptosis. Reverse transcription­quantitative polymerase chain reaction and western blot analysis were performed to detect mRNA and protein expression, respectively, including RbAp48, phosphoinositide 3­kinase (PI3K) and protein kinase B (Akt). The results revealed that radiation enhanced the expression level of RbAp48 in AGS cells, and that RbAp48 combined with radiation reduced AGS cell proliferation. In addition, RbAp48 combined with radiation resulted in G2 phase arrest and induced apoptosis via regulation of the PI3K/Akt pathway. In conclusion, it was demonstrated that overexpression of RbAp48 enhanced the radiosensitivity of AGS gastric cancer cells via suppression of PI3K/Akt pathway activity, suggesting that RbAp48 may hold potential as a gene therapeutic strategy in the future, aiding in the treatment of gastric cancer.


Assuntos
Mucosa Gástrica/efeitos da radiação , Regulação Neoplásica da Expressão Gênica , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Tolerância a Radiação/genética , Proteína 4 de Ligação ao Retinoblastoma/genética , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos da radiação , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína 4 de Ligação ao Retinoblastoma/metabolismo , Transdução de Sinais
9.
World J Gastroenterol ; 23(33): 6155-6163, 2017 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-28970731

RESUMO

AIM: To identify the clinical features of gastric mucosa-associated lymphoid tissue (MALT) lymphoma with extra copies of MALT1. METHODS: This is a multi-centered, retrospective study. We reviewed 146 patients with MALT lymphoma in the stomach who underwent fluorescence in situ hybridization analysis for t(11;18) translocation. Patients were subdivided into patients without t(11;18) translocation or extra copies of MALT1 (Group A, n = 88), patients with t(11;18) translocation (Group B, n = 27), and patients with extra copies of MALT1 (Group C, n = 31). The clinical background, treatment, and outcomes of each group were investigated. RESULTS: Groups A and C showed slight female predominance, whereas Group B showed slight male predominance. Mean ages and clinical stages at lymphoma diagnosis were not different between groups. Complete response was obtained in 61 patients in Group A (69.3%), 22 in Group B (81.5%), and 21 in Group C (67.7%). Helicobacter pylori (H. pylori) eradication alone resulted in complete remission in 44 patients in Group A and 13 in Group C. In Group B, 14 patients underwent radiotherapy alone, which resulted in lymphoma disappearance. Although the difference was not statistically significant, event-free survival in Group C tended to be inferior to that in Group A (P = 0.10). CONCLUSION: Patients with t(11;18) translocation should be treated differently from others. Patients with extra copies of MALT1 could be initially treated with H. pylori eradication, similar to patients without t(11;18) translocation or extra copies of MALT1.


Assuntos
Antibacterianos/uso terapêutico , Antineoplásicos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Linfoma de Zona Marginal Tipo Células B/terapia , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/genética , Neoplasias Gástricas/terapia , Idoso , Aneuploidia , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 18/genética , Intervalo Livre de Doença , Feminino , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Mucosa Gástrica/efeitos da radiação , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Humanos , Hibridização in Situ Fluorescente , Linfoma de Zona Marginal Tipo Células B/genética , Linfoma de Zona Marginal Tipo Células B/microbiologia , Linfoma de Zona Marginal Tipo Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/genética , Radioterapia/métodos , Estudos Retrospectivos , Fatores Sexuais , Neoplasias Gástricas/genética , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/mortalidade , Translocação Genética , Resultado do Tratamento
10.
Hum Pathol ; 50: 11-4, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26997433

RESUMO

Yttrium-90 microsphere radioembolization ((90)Y MRE) is a therapy for liver malignancies by permanently implanting (90)Y-containing microspheres into tumors via hepatic artery. The etiology of persistent gastric ulcerations in patients presenting months after treatment remains unclear. Three patients who presented with gastric ulceration 4 to 13 months after (90)Y MRE were examined by esophagogastroduodenoscopy and biopsies. Pathological examinations showed multiple (90)Y microspheres scattered within the lamina propria and submucosa. Most of the microspheres were distributed in a linear fashion, consistent with an intravascular location; however, the vascular lumen and endothelial cells were not present. The microspheres were surrounded by fibrotic tissue infiltrated by chronic inflammatory cells and rare neutrophils. Epithelial granulation without pititis and miniaturized glands with intervening fibrosis were noted, compatible with chronic ischemic changes. These findings suggest that the persistent gastric ulceration is a result of localized ischemic injury in response to (90)Y MRE-induced vascular damage.


Assuntos
Capilares/efeitos da radiação , Embolização Terapêutica/efeitos adversos , Mucosa Gástrica/efeitos da radiação , Isquemia/etiologia , Neoplasias Hepáticas/radioterapia , Lesões por Radiação/etiologia , Compostos Radiofarmacêuticos/efeitos adversos , Úlcera Gástrica/etiologia , Radioisótopos de Ítrio/efeitos adversos , Idoso , Biópsia , Capilares/química , Capilares/patologia , Doença Crônica , Embolização Terapêutica/métodos , Endoscopia do Sistema Digestório , Feminino , Fibrose , Mucosa Gástrica/irrigação sanguínea , Mucosa Gástrica/patologia , Humanos , Imuno-Histoquímica , Isquemia/patologia , Neoplasias Hepáticas/patologia , Masculino , Microesferas , Pessoa de Meia-Idade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Lesões por Radiação/patologia , Compostos Radiofarmacêuticos/administração & dosagem , Úlcera Gástrica/patologia , Fatores de Tempo , Resultado do Tratamento , Radioisótopos de Ítrio/administração & dosagem
11.
Anal Quant Cytopathol Histpathol ; 37(3): 169-76, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26173354

RESUMO

OBJECTIVE: To understand the effects of γ-ray irradiation (IR) on the proliferation of gastric mucosal cells and to investigate the possible mechanisms that affect gastric mucosal cell proliferation. STUDY DESIGN: C57BL/6J mice were exposed to IR at various doses (4, 8, and 15 Gy). We measured the changes of gastric mucosal BrdU-positive cells and the expression of ß-catenin protein in the isthmus of fundic glands at days 1, 3, and 5 after irradiation. RESULTS: Our data showed that the mice that received 15 Gy IR died within 4 days. IR caused gastric mucosal injury in mice, and the degree of injury increased along with the increasing doses. Compared with the control group, the proliferation of gastric mucosal cells was inhibited 1 day after irradiation. Cell proliferation was recovered on day 5 after low-dose (4 and 8 Gy) IR, while proliferation was continuously inhibited after high-dose (15 Gy) IR. ß-catenin expression was increased and had a translocation in the isthmus of gastric mucosa. CONCLUSION: These findings suggest that gastric mucosa is sensitive to irradiation. The Wnt/ß-catenin pathway is activated and plays a role in cell proliferation of gastric mucosa upon irradiation.


Assuntos
Proliferação de Células/efeitos da radiação , Mucosa Gástrica/efeitos da radiação , Lesões Experimentais por Radiação/patologia , Animais , Mucosa Gástrica/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Radioterapia/efeitos adversos
12.
Int J Radiat Oncol Biol Phys ; 87(5): 1000-6, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24267968

RESUMO

PURPOSE: To determine the maximum tolerated radiation dose (MTD) of an integrated boost to the tumor subvolume infiltrating vessels, delivered simultaneously with radical dose to the whole tumor and concomitant capecitabine in patients with pretreated advanced pancreatic adenocarcinoma. METHODS AND MATERIALS: Patients with stage III or IV pancreatic adenocarcinoma without progressive disease after induction chemotherapy were eligible. Patients underwent simulated contrast-enhanced four-dimensional computed tomography and fluorodeoxyglucose-labeled positron emission tomography. Gross tumor volume 1 (GTV1), the tumor, and GTV2, the tumor subvolume 1 cm around the infiltrated vessels, were contoured. GTVs were fused to generate Internal Target Volume (ITV)1 and ITV2. Biological tumor volume (BTV) was fused with ITV1 to create the BTV+Internal Target Volume (ITV) 1. A margin of 5/5/7 mm (7 mm in cranium-caudal) was added to BTV+ITV1 and to ITV2 to create Planning Target Volume (PTV) 1 and PTV2, respectively. Radiation therapy was delivered with tomotherapy. PTV1 received a fixed dose of 44.25 Gy in 15 fractions, and PTV2 received a dose escalation from 48 to 58 Gy as simultaneous integrated boost (SIB) in consecutive groups of at least 3 patients. Concomitant chemotherapy was capecitabine, 1250 mg/m(2) daily. Dose-limiting toxicity (DLT) was defined as any treatment-related G3 nonhematological or G4 hematological toxicity occurring during the treatment or within 90 days from its completion. RESULTS: From June 2005 to February 2010, 25 patients were enrolled. The dose escalation on the SIB was stopped at 58 Gy without reaching the MTD. One patient in the 2(nd) dose level (50 Gy) had a DLT: G3 acute gastric ulcer. Three patients had G3 late adverse effects associated with gastric and/or duodenal mucosal damage. All patients received the planned dose of radiation. CONCLUSIONS: A dose of 44.25 Gy in 15 fractions to the whole tumor with an SIB of 58 Gy to small tumor subvolumes concomitant with capecitabine is feasible in chemotherapy-pretreated patients with advanced pancreatic cancer.


Assuntos
Adenocarcinoma/radioterapia , Antimetabólitos Antineoplásicos/uso terapêutico , Quimiorradioterapia/métodos , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Neoplasias Pancreáticas/terapia , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos , Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Idoso , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/efeitos da radiação , Capecitabina , Quimiorradioterapia/efeitos adversos , Desoxicitidina/uso terapêutico , Fracionamento da Dose de Radiação , Duodeno/efeitos da radiação , Estudos de Viabilidade , Feminino , Fluoruracila/uso terapêutico , Mucosa Gástrica/efeitos da radiação , Humanos , Quimioterapia de Indução/efeitos adversos , Quimioterapia de Indução/métodos , Mucosa Intestinal/efeitos da radiação , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Órgãos em Risco/efeitos da radiação , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Radioterapia de Intensidade Modulada/efeitos adversos , Carga Tumoral
13.
Surg Endosc ; 27(11): 4241-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23793803

RESUMO

BACKGROUND: Recently, endoscopic submucosal dissection (ESD) has been performed to treat early gastric cancer. The en bloc resection rate of ESD has been reported to be higher than that of conventional endoscopic mucosal resection (EMR), and ESD can resect larger lesions than EMR. However, ESD displays a higher complication rate than conventional EMR. Therefore, the development of devices that would increase the safety of ESD is desired. Lasers have been extensively studied as a possible alternative to electrosurgical tools. However, laser by itself easily resulted in perforation upon irradiation of the gastrointestinal tract. We hypothesized that performing ESD using a CO2 laser with a submucosal laser absorber could be a safe and simple treatment for early gastric cancer. To provide proof of concept regarding the feasibility of ESD using a CO2 laser with submucosally injected laser absorber solution, an experimental study in ex vivo and in vivo porcine models was performed. METHODS: Five endoscopic experimental procedures using a carbon dioxide (CO2) laser were performed in a resected porcine stomach. In addition, three endoscopic experimental procedures using a CO2 laser were performed in living pigs. RESULTS: In the ex vivo study, en bloc resections were all achieved without perforation and muscular damage. In addition, histological evaluations could be performed in all of the resected specimens. In the in vivo study, en bloc resections were achieved without perforation and muscular damage, and uncontrollable hemorrhage did not occur during the procedures. CONCLUSIONS: Endoscopic submucosal dissection using a CO2 laser with a submucosal laser absorber is a feasible and safe method for the treatment of early gastric cancer.


Assuntos
Dissecação/instrumentação , Dissecação/métodos , Endoscopia Gastrointestinal/instrumentação , Endoscopia Gastrointestinal/métodos , Mucosa Gástrica/efeitos da radiação , Mucosa Gástrica/cirurgia , Lasers de Gás/uso terapêutico , Animais , Estudos de Viabilidade , Mucosa Gástrica/patologia , Ácido Hialurônico/administração & dosagem , Técnicas In Vitro , Injeções , Modelos Animais , Protetores contra Radiação/administração & dosagem , Suínos , Resultado do Tratamento
14.
Stomatologiia (Mosk) ; 92(6): 12-5, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24429780

RESUMO

The efficiency of remaxol for prevention and treatment of chemoradiotherapy toxicity effects in patients with advanced oral cancer was evaluated. Ninety-five oral cancer patients were using remaxol both locally (mouth rinse solution) and by intravenous infusion, 87 patients were included in control group. Intravenous remaxol proved to be effective for mucositis and nephrotoxicity prevention by chemoradiotherapy.


Assuntos
Quimiorradioterapia/efeitos adversos , Neoplasias Bucais/terapia , Antissépticos Bucais/administração & dosagem , Succinatos/administração & dosagem , Administração Intravenosa , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/efeitos da radiação , Humanos , Rim/efeitos dos fármacos , Rim/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/efeitos dos fármacos , Mucosa Bucal/efeitos da radiação , Lesões por Radiação/tratamento farmacológico , Lesões por Radiação/etiologia , Estudos Retrospectivos , Estomatite/tratamento farmacológico , Estomatite/etiologia
15.
Am J Physiol Gastrointest Liver Physiol ; 303(8): G915-26, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22899822

RESUMO

CD24 is expressed in the putative stem cells within several tissues and is overexpressed in gastric and colonic adenocarcinomas. Perturbed CD24 expression may therefore alter the response of gastrointestinal epithelia to damage-inducing stimuli that induce cancer. We have investigated the effects of CD24 deletion on gastric responses to Helicobacter felis infection and γ-irradiation using CD24-null mice. Gastric CD24 expression was determined by immunohistochemistry in C57BL/6 mice. Female CD24-null and C57BL/6 mice were infected with H. felis for 6 wk, and inflammation, proliferation, apoptosis, and parietal cell numbers were assessed in gastric tissue sections. Apoptosis and proliferation were analyzed on a cell-positional basis in stomach, small intestine, and colon of CD24-null and C57BL/6 mice following γ-irradiation. Apoptosis was also assessed in HT29 cells following CD24 siRNA transfection. Of CD24-positive cells in the gastric corpus, 98% were H(+)-K(+)-ATPase-expressing parietal cells. CD24-null mice showed more prominent gastric H. felis colonization than C57BL/6 mice but displayed a marked reduction in corpus inflammation, reduced Ki67 labeling, and less gastric atrophy 6 wk following infection. Corpus apoptosis was elevated in CD24-null mice, but this did not increase further with H. felis infection as observed in C57BL/6 mice. More apoptotic cells were found following γ-irradiation in the stomach, small intestine, and colon of CD24-null mice and following CD24 knockdown in vitro. In conclusion, CD24 is expressed in gastric parietal cells, where it modulates gastric responses to H. felis and γ-radiation. CD24 also regulates susceptibility to apoptosis in the distal murine gastrointestinal tract.


Assuntos
Apoptose/fisiologia , Antígeno CD24/metabolismo , Mucosa Gástrica/metabolismo , Infecções por Helicobacter/metabolismo , Células Parietais Gástricas/metabolismo , Animais , Antígeno CD24/genética , Feminino , Raios gama , Mucosa Gástrica/microbiologia , Mucosa Gástrica/efeitos da radiação , Infecções por Helicobacter/genética , Infecções por Helicobacter/patologia , Helicobacter felis , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Parietais Gástricas/microbiologia , Células Parietais Gástricas/efeitos da radiação , Estômago/microbiologia , Estômago/efeitos da radiação
16.
Int J Radiat Biol ; 87(10): 1045-51, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21745002

RESUMO

PURPOSE: To study the effect of aqueous propolis extract (AEP) against indomethacin (Indo)-induced gastric ulcers in irradiated and non-irradiated rats. MATERIALS AND METHODS: Animals were irradiated at different radiation dose levels before the induction of ulcers. AEP was injected orally 1 hour before induction of gastric ulcers and the effects compared with those of lansoprazole (Lanso), which was used as a reference anti-ulcerogenic drug. RESULTS: Pretreatment of rats, either irradiated or non-irradiated, with AEP effectively protected against Indo-induced gastric ulceration. This was associated with a reduction in acid output and peptic activity and an increase in the secretion of mucin. The mucosal prostaglandin E(2) (PGE(2)) level was also increased. The levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1ß) were suppressed to the same extent after treatment. Both propolis and Lanso were effective in reducing the number of gastric lesions as well as the plasma level of malondialdehyde (MDA). CONCLUSIONS: These findings indicate that the gastroprotective effect of AEP could be of value in the management of excessive gastric damage induced by radiation exposure.


Assuntos
Antiulcerosos/uso terapêutico , Raios gama , Extratos Vegetais/uso terapêutico , Própole/uso terapêutico , Protetores contra Radiação/uso terapêutico , Úlcera Gástrica/tratamento farmacológico , Animais , Antiulcerosos/farmacologia , Citocinas/metabolismo , Citocinas/efeitos da radiação , Dinoprostona/metabolismo , Dinoprostona/efeitos da radiação , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Mucosa Gástrica/efeitos da radiação , Indometacina/toxicidade , Interleucina-1beta/metabolismo , Interleucina-1beta/efeitos da radiação , Masculino , Malondialdeído/metabolismo , Malondialdeído/efeitos da radiação , Ratos , Ratos Wistar , Soluções/química , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/patologia , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/efeitos da radiação , Água/química
17.
J Nanosci Nanotechnol ; 11(11): 9528-35, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22413242

RESUMO

We explored the biocompatible gold nanoparticles (GNPs) with surface modified by chitosan in the applications of cell's response to X-ray irradiation. Substantial amounts of chitosan modified gold nanoparticles (CS-GNPs) were found to be internalized in cell cytoplasm revealed by transmission electron microscopy. Their in vitro cytotoxicity effects on MGC-803 cells and GES-1 cells were observed at 24, 48 and 72 h. The MTT results showed that CS-GNPs own excellent biocompatibility. The dose enhancement based on CS-GNPs induced the damage of MGC-803 cells under X-ray irradiation, monitored by clonogenic cell survival assay. We also investigated their effects on the survival rates of MGC-803 cells during irradiation for a dose up to 10 Gy using a radio-oncology linear accelerator (6 MeV). The survival fraction of cells incubated with different concentration of CS-GNPs was obviously reduced in comparison with that irradiation alone. The result also revealed an increase of cell inhibition with increasing the concentration of CS-GNPs. In conclusion, CS-GNPs can enhance the cell radiation therapeutic sensitivity, and have potential application in tumor irradiation therapy in near future.


Assuntos
Quitosana/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/efeitos da radiação , Ouro/farmacologia , Nanopartículas Metálicas/química , Radiossensibilizantes/farmacologia , Linhagem Celular Transformada , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Quitosana/química , Mucosa Gástrica/citologia , Ouro/química , Humanos , Radiossensibilizantes/química , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/radioterapia , Raios X
18.
Int J Radiat Biol ; 86(10): 867-79, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20653343

RESUMO

PURPOSE: To investigate the protective effect of immune-enhanced diet (IED) on chemoradiation-induced injury of the gastrointestinal mucosa. MATERIALS AND METHODS: Forty-eight Sprague-Dawley rats were divided into control (C, n=6), irradiation (IR, n=14), fluoropyrimidine (5-FU, n=14)-treated, IR + 5-FU (n=14)-treated groups. Half of each irradiated and/or 5-FU-treated groups were previously fed with IED containing arginine, omega-3-fatty acids and RNA fragments, while the other half were fed a standard rat diet (SD) for eight days before the induction of IR or injection of 5-FU. In IR groups, whole abdominal irradiation (11 Gy) was performed with 6 MV photons. In the 5-FU groups, fluoropyrimidine (100 mg/kg) was administered intraperitoneally 30 min prior to irradiation. All animals were sacrificed on the 4th day of IR or 5-FU injection. RESULTS: Bacterial colony counts in the ceca and mesenteric lymph nodes of IED-fed rats, which have received either 5-FU and/or irradiation were significantly lower than the corresponding SD-fed groups. Morphometric results revealed that gastric, ileal and colonic injuries were less in IED-treated IR or IR + 5-FU + IED groups, as compared to SD-fed groups. However, IED did not alter DNA fragmentation ratios. CONCLUSION: Prophylactic feeding of IED has a protective effect on chemoradiation-induced gastrointestinal injury, which appears to involve the eradication of bacterial overgrowth.


Assuntos
Dieta , Trato Gastrointestinal/lesões , Trato Gastrointestinal/efeitos da radiação , Lesões Experimentais por Radiação/imunologia , Lesões Experimentais por Radiação/prevenção & controle , Animais , Bactérias/crescimento & desenvolvimento , Bactérias/imunologia , Bactérias/efeitos da radiação , Fragmentação do DNA/efeitos da radiação , Feminino , Mucosa Gástrica/imunologia , Mucosa Gástrica/lesões , Mucosa Gástrica/microbiologia , Mucosa Gástrica/efeitos da radiação , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/patologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/lesões , Mucosa Intestinal/microbiologia , Mucosa Intestinal/efeitos da radiação , Masculino , Lesões Experimentais por Radiação/patologia , Ratos
20.
Z Gastroenterol ; 48(5): 546-50, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20449787

RESUMO

BACKGROUND: Cancer of unknown primary (CUP) is defined as histologically confirmed metastases in the absence of an identifiable primary tumor. Patients with solely liver metastases from adenocarinomas represent the most frequent subgroup with an unfavourable prognosis. The medium survival averages 6 to 9 months. No chemotherapheutic standard has been established. CASE: We present a patient with hepatic CUP. After cycles of chemotherapy and hemihepatectomy the tumor returned and showed hepatic progression. The patient was evaluated for selective internal radiation therapy (SIRT). Three years after diagnosis she is still alive and tumorfree. Despite a good result and disease control our patient suffered radiation-induced ulceration in the oesophagus, stomach, and duodenum. This side effect appears in up to 12 % of patients, often very late after treatment, is refractory to pharmacotherapy and persistent over a long time. CONCLUSIONS: SIRT is a new, effective treatment in patients with hepatic CUP. Because of the anticipated increase of this therapy, adverse side effects such as ulcerations in the upper-GI tract secondary to ectopic implantation of microspheres may be seen more commonly. Awareness of this and the recognition of microspheres in biopsies is cardinal for appropriate management and maintenance of the patient's quality of life.


Assuntos
Adenocarcinoma/radioterapia , Adenocarcinoma/secundário , Braquiterapia/efeitos adversos , Úlcera Duodenal/patologia , Embolização Terapêutica , Doenças do Esôfago/patologia , Esôfago/efeitos da radiação , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Neoplasias Primárias Desconhecidas/radioterapia , Lesões por Radiação/patologia , Úlcera Gástrica/patologia , Úlcera/patologia , Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/cirurgia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Progressão da Doença , Duodeno/patologia , Duodeno/efeitos da radiação , Endoscopia do Sistema Digestório , Esôfago/patologia , Feminino , Mucosa Gástrica/patologia , Mucosa Gástrica/efeitos da radiação , Hepatectomia , Humanos , Mucosa Intestinal/patologia , Mucosa Intestinal/efeitos da radiação , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Microesferas , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasias Primárias Desconhecidas/irrigação sanguínea , Neoplasias Primárias Desconhecidas/tratamento farmacológico , Neoplasias Primárias Desconhecidas/cirurgia , Radioterapia Adjuvante
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