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1.
Radiother Oncol ; 176: 101-107, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36167194

RESUMO

BACKGROUND AND PURPOSE: This study aims to investigate how accurate our deep learning (DL) dose prediction models for intensity modulated radiotherapy (IMRT) and pencil beam scanning (PBS) treatments, when chained with normal tissue complication probability (NTCP) models, are at identifying esophageal cancer patients who are at high risk of toxicity and should be switched to proton therapy (PT). MATERIALS AND METHODS: Two U-Net were created, for photon (XT) and proton (PT) plans, respectively. To estimate the dose distribution for each patient, they were trained on a database of 40 uniformly planned patients using cross validation and a circulating test set. These models were combined with a NTCP model for postoperative pulmonary complications. The NTCP model used the mean lung dose, age, histology type, and body mass index as predicting variables. The treatment choice is then done by using a ΔNTCP threshold between XT and PT plans. Patients with ΔNTCP ≥ 10% were referred to PT. RESULTS: Our DL models succeed in predicting dose distributions with a mean error on the mean dose to the lungs (MLD) of 1.14 ± 0.93% for XT and 0.66 ± 0.48% for PT. The complete automated workflow (DL chained with NTCP) achieved 100% accuracy in patient referral. The average residual (ΔNTCP ground truth - ΔNTCP predicted) is 1.43 ± 1.49%. CONCLUSION: This study evaluates our DL dose prediction models in a broader patient referral context and demonstrates their ability to support clinical decisions.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Aprendizado Profundo , Neoplasias Esofágicas , Terapia com Prótons , Radioterapia de Intensidade Modulada , Humanos , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/efeitos adversos , Terapia com Prótons/efeitos adversos , Probabilidade , Neoplasias Esofágicas/radioterapia , Dosagem Radioterapêutica
2.
Sci Rep ; 10(1): 7305, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350392

RESUMO

Helicobacter pylori colonization may affect the mucosal immune system through modification of microbiota composition and their interactions with the host. We hypothesized that maternal H. pylori status affects the maternal intestinal microbiota of both mother and newborn. In this study, we determine the structure of the fecal microbiota in mothers and neonates according to maternal H. pylori status and delivery mode. We included 22 mothers and H. pylori infection was determined by fecal antigen test. Eleven mothers (50%) were H. pylori-positive (7 delivering vaginally and 4 by C-section), and 11 were negative (6 delivering vaginally and 5 by C-section). Stool samples were obtained from mothers and infants and the fecal DNA was sequenced. The fecal microbiota from mothers and their babies differed by the maternal H. pylori status, only in vaginal birth, not in C-section delivery. All 22 infants tested negative for fecal H. pylori at 15 days of age, but those born vaginally -and not those by C-section- showed differences in the infant microbiota by maternal H. pylori status (PERMANOVA, p = 0.01), with higher abundance of Enterobacteriaceae and Veillonella, in those born to H. pylori-positive mothers. In conclusion, the structure of the infant fecal microbiota is affected by the maternal H. pylori status only in infants born vaginally, suggesting that the effect could be mediated by labor and birth exposures.


Assuntos
Fezes/microbiologia , Microbioma Gastrointestinal , Infecções por Helicobacter/microbiologia , Helicobacter pylori , Transmissão Vertical de Doenças Infecciosas , Adulto , Enterobacteriaceae , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Veillonella
3.
Dig Dis Sci ; 65(2): 565-575, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31392473

RESUMO

BACKGROUND AND AIMS: Nodular gastropathy (NG) is an inflammatory condition of the gastric mucosa characterized by the endoscopic detection of multiple millimeter protrusions. A strong association between NG and Helicobacter pylori and a possible role of NG as a risk factor for undifferentiated gastric cancer have been described. The aim of this study was to characterize the pathogenic and inflammatory profile of patients with NG. METHODS: Adult patients referred for upper gastrointestinal endoscopy were prospectively enrolled in this study. H. pylori infection status was determined by rapid urease test. Biopsies were stained with hematoxylin-eosin. Sydney and OLGA scores were used to assess gastritis characteristics and gastric cancer risk. PCR analysis was performed to determine bacterial load and virulence factors CagA (and its EPIYA motifs) and VacA alleles. Finally, gastric mucosa cytokine gene expression (IL-8, IL-1ß, and TNF-α) was determined by real-time RT-PCR. RESULTS: Forty-eight patients, mean age of 36 years, were recruited. All NG patients were infected by H. pylori. OLGA score was similar in both groups (NG patients and non-NG patients). NG patients had higher bacterial load in the gastric corpus (p = 0.01) and significantly less pro-inflammatory cytokine levels than non-NG infected patients (p = 0.01). CONCLUSIONS: In our study, NG is not associated with preneoplastic lesions. An increase in bacterial load without a concomitant increase in mucosal inflammatory cytokine responses in H. pylori-infected subjects with NG may represent a general dampening of immune responses or an additional mechanism of H. pylori active immune evasion.


Assuntos
Carga Bacteriana , Citocinas/genética , Mucosa Gástrica/microbiologia , Gastrite/microbiologia , Infecções por Helicobacter/microbiologia , Adulto , Antígenos de Bactérias , Proteínas de Bactérias , Estudos de Casos e Controles , Citocinas/metabolismo , Endoscopia do Sistema Digestório , Endossonografia , Feminino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Gastrite/genética , Gastrite/metabolismo , Gastrite/patologia , Infecções por Helicobacter/genética , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/patologia , Helicobacter pylori/genética , Helicobacter pylori/patogenicidade , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Masculino , Pessoa de Meia-Idade , Imagem de Banda Estreita , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
4.
Cienc. Trab ; 20(63): 145-150, dic. 2018. tab
Artigo em Inglês | LILACS | ID: biblio-984166

RESUMO

Abstract: Within the framework of Corporate Social Responsibility, workers' perceptions regarding human resource policies and practices imple mented by the organization are relevant to the organizational commit ment that they display towards the institution. We analyze the rela tionship between workers' perceptions of company human resource policies and practices and the multidimensional construct of organi zational commitment through cross-sectional correlational research for a sample of 89 workers from 7 different organizations in the Ñuble Province, Chile. This study aims to understand workers' perceptions regarding the implementation, by the organization, of certain labor policies and practices, and its relationship with the degree of organi zational commitment, measured through the instrument proposed by Meyer and Allen in 1991. The results show that most of the good practices analyzed have a high positive and moderate correlation with organizational commitment. The positive relationship between com mitment and at least one of the aspects of each "Good Labor Practice" studied is highlighted: Benefits and Compensations, Health and Safety, Human Resources Processes, Training and Professional Development and Work Conciliation.


Resumen: En el marco de la Responsabilidad Social Empresarial, la percepción de los trabajadores respecto de las políticas y prácticas de recursos humanos que implementa la organización, son relevantes en su compromiso organizacional. Se analiza la relación entre la percep ción del trabajador de las políticas y prácticas de recursos humanos de la empresa y el constructo multidimensional de compromiso organizacional, a través de una investigación de tipo correlacional, de corte transversal, para una muestra de 89 trabajadores prove nientes de 7 organizaciones de la Provincia de Ñuble. El objetivo es determinadar si las políticas y prácticas laborales implementadas por las empresas se relaciona con el grado de compromiso organi zacional que manifiesta el trabajador, medido a trevés del instru mento propuesto por Meyer y Allen en 1991. Los resultados mues tran que la mayoría de las buenas prácticas analizadas, tienen una correlación positiva y moderada con el compromiso con la organi zación. Se destaca la relación positiva entre el compromiso y al menos uno de los aspectos de cada "Buena Práctica Laboral" estu diada: Beneficios y Compensaciones, Salud y Seguridad, Procesos de Recursos Humanos, Capacitación y Desarrollo Profesional, y Conciliación Laboral.


Assuntos
Humanos , Masculino , Feminino , Responsabilidade Social , Organizações , Recursos Humanos/organização & administração , Engajamento no Trabalho , Lealdade ao Trabalho , Chile , Estudos Transversais , Inquéritos e Questionários
5.
J Pediatr Gastroenterol Nutr ; 64(3): e56-e60, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27159208

RESUMO

INTRODUCTION: Failure to eradicate Helicobacter pylori despite antibiotic treatment is generally attributed to increasing clarithromycin resistance conferred by point mutations in the 23S-rRNA gene or metronidazole resistance attributed to rdxA gene (HP0954) deletion in patients. Scarce data for pediatric population are available from developing countries. OBJECTIVES: The aim of the present study was to determine the presence of A2142G/C and A2143G mutations in the 23S-rRNA gene and/or rdxA gene (HP0954) deletion in a group of symptomatic H pylori-infected children recruited from an area with high infection rate and risk of gastric cancer. PATIENTS AND METHODS: We recruited 118 patients referred for upper endoscopy for gastrointestinal symptoms. The presence of H pylori was determined by urease test and histological staining. The rdxA gene (HP0954) deletion, and 2142G/C and A2143G mutations were determined by polymerase chain reaction-restriction fragment length polymorphism. A subgroup of infected patients received a 14-day regimen of omeprazole, amoxicillin, and clarithromycin. The effectiveness of this regime was determined by stool antigen determination 8 weeks after treatment. RESULTS: About 21% of the analyzed infected patients showed mutation in the 23S-rRNA gene, with the A2143G transition as the more frequent mutation, and 2% of the patients showed rdxA gene (HP0954) deletion. After treatment, 25% of the patients continued to harbor the bacteria; of these, 67% carried the A2143G mutation. CONCLUSIONS: H pylori-infected pediatric patients from Chile show high prevalence of the mutation responsible for clarithromycin resistance. The failure to eradicate H pylori can be attributed to the presence of the A2143G mutation.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Claritromicina/farmacologia , Farmacorresistência Bacteriana/genética , Infecções por Helicobacter/microbiologia , Helicobacter pylori/efeitos dos fármacos , Nitrorredutases/genética , RNA Ribossômico 23S/genética , Adolescente , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Antibacterianos/uso terapêutico , Sequência de Bases , Criança , Pré-Escolar , Chile/epidemiologia , Claritromicina/uso terapêutico , Países em Desenvolvimento , Feminino , Seguimentos , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/epidemiologia , Helicobacter pylori/genética , Humanos , Masculino , Metronidazol/farmacologia , Metronidazol/uso terapêutico , Mutação Puntual , Polimorfismo de Fragmento de Restrição , Prevalência , Deleção de Sequência , Resultado do Tratamento
6.
Rev. chil. pediatr ; 87(6): 474-479, Dec. 2016. tab
Artigo em Espanhol | LILACS | ID: biblio-844568

RESUMO

Introducción: La infección por H. pylori se adquiere tempranamente en la infancia. Sin embargo, existe escasa información acerca del rol de la lactancia materna y la adquisición de la bacteria en la etapa neonatal/lactante. Objetivo: Evaluar algunos factores que afectan la adquisición de H. pylori en recién nacidos y lactantes hijos de madres infectadas. Pacientes y método: Reclutamiento consecutivo de binomios madre-hijo en maternidad, inmediatamente posparto. Luego de la firma de consentimiento informado, se obtuvo una muestra de deposición de la madre, previo al alta. Posteriormente se obtuvieron 3 muestras de deposición de los recién nacidos/lactantes a los 15, 60 y 90 días de vida, para la detección de antígeno en deposición de H. pylori (HpSAg monoclonal, sensibilidad 94% y especificidad 97%). Además se registraron variables socio-epidemiológicas y biomédicas. Resultados: Se reclutaron 32 binomios madre-hijo, 64 sujetos. Promedio de edad materna de 30,1 ± 5,1 años, 53% parto eutócico, 85% con lactancia materna exclusiva al final del seguimiento. Se encontró 13 madres (40%) infectadas por H. pylori. No hubo infección por H. pylori en los recién nacidos y lactantes a los 3 meses de seguimiento. No hubo diferencia significativa en el nivel socioeconómico entre madres infectadas versus no infectadas (ambos grupos en nivel socioeconómico muy alto: 28% y 32% respectivamente, p = 0,15), ni en el número de habitantes por domicilio entre madres infectadas y no infectadas (3,8 ± 0,8 vs 4,2 ± 1,8 personas, p = 0,18). Conclusión: A pesar de tener un alto porcentaje de madres infectadas por H. pylori, no hubo recién nacidos/lactantes infectados al tercer mes de vida. El rol protector de la lactancia maternal no se puede descartar.


Introduction: H. pylori infection is acquired early in childhood. However, there is little information available regarding the role of breastfeeding and neonatal acquisition of the infection. Objective: To evaluate factors affecting the acquisition of H. pylori in newborns and infants from infected mothers. Patients and method: Consecutive mothers and their newborns were recruited into the study from the maternity unit, immediately after delivery. After signing informed consent, one stool sample from the mother was obtained before hospital discharge. Three stool samples of the newborns were then collected at home at 15, 60, and 90 days of life, for the detection of H. pylori antigen (Monoclonal HpSAg, sensitivity 94% and specificity 97%). The socio-epidemiological and biomedical variables were also analysed using a questionnaire. Results: A total of 32 mother-child pairs (64 subjects) were enrolled. The mean maternal age was 30.1 ± 5.1 years, with 53% vaginal delivery, and 85% exclusively breastfed. There were 13 (40%) infected mothers. No H. pylori infection was detected in newborns and infants up to 3 months of follow-up. No significant differences were found in socioeconomic level between infected versus non-infected mothers (both groups mostly in the very high socioeconomic category: 28% and 32%, respectively, P = .15) and in the number of family members between infected versus non-infected mothers (3.8 ± 0.8 vs 4.2 ± 1.8 persons, P = .18). Conclusion: Despite having a significant percentage of H. pylori-infected mothers, no newborn was infected at the third month of life. The protective role of breastfeeding cannot be ruled out.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Adulto , Aleitamento Materno , Helicobacter pylori/isolamento & purificação , Infecções por Helicobacter/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Fatores Socioeconômicos , Fatores de Tempo , Inquéritos e Questionários , Seguimentos , Infecções por Helicobacter/transmissão , Infecções por Helicobacter/epidemiologia , Sensibilidade e Especificidade
7.
Rev Chil Pediatr ; 87(6): 474-479, 2016.
Artigo em Espanhol | MEDLINE | ID: mdl-27425773

RESUMO

INTRODUCTION: H. pylori infection is acquired early in childhood. However, there is little information available regarding the role of breastfeeding and neonatal acquisition of the infection. OBJECTIVE: To evaluate factors affecting the acquisition of H. pylori in newborns and infants from infected mothers. PATIENTS AND METHOD: Consecutive mothers and their newborns were recruited into the study from the maternity unit, immediately after delivery. After signing informed consent, one stool sample from the mother was obtained before hospital discharge. Three stool samples of the newborns were then collected at home at 15, 60, and 90 days of life, for the detection of H. pylori antigen (Monoclonal HpSAg, sensitivity 94% and specificity 97%). The socio-epidemiological and biomedical variables were also analysed using a questionnaire. RESULTS: A total of 32 mother-child pairs (64 subjects) were enrolled. The mean maternal age was 30.1±5.1 years, with 53% vaginal delivery, and 85% exclusively breastfed. There were 13 (40%) infected mothers. No H. pylori infection was detected in newborns and infants up to 3 months of follow-up. No significant differences were found in socioeconomic level between infected versus non-infected mothers (both groups mostly in the very high socioeconomic category: 28% and 32%, respectively, P=.15) and in the number of family members between infected versus non-infected mothers (3.8±0.8 vs 4.2±1.8 persons, P=.18). CONCLUSION: Despite having a significant percentage of H. pylori-infected mothers, no newborn was infected at the third month of life. The protective role of breastfeeding cannot be ruled out.


Assuntos
Aleitamento Materno , Infecções por Helicobacter/prevenção & controle , Helicobacter pylori/isolamento & purificação , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Adulto , Feminino , Seguimentos , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/transmissão , Humanos , Lactente , Recém-Nascido , Masculino , Sensibilidade e Especificidade , Fatores Socioeconômicos , Inquéritos e Questionários , Fatores de Tempo
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