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1.
Prev Vet Med ; 224: 106095, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38232517

RESUMO

Pancreas Disease (PD) is a viral disease that affects Atlantic salmon (Salmo salar) in Norwegian, Scottish and Irish aquaculture. It is caused by salmonid alphavirus (SAV) and represents a significant problem in salmonid farming. Infection with SAV leads to reduced growth, mortality, product downgrading, and has a significant financial impact for the farms. The overall aim of this study is to evaluate the effect of various factors on the transmission of SAV and to create a predictive model capable of providing an early warning system for salmon farms within the Norwegian waters. Using a combination of publicly available databases, specifically BarentsWatch, and privately held PCR analyses a feature set consisting of 11 unique features was created based on the input parameters of the databases. An ensemble model was developed based on this feature set using XG-Boost, Ada-Boost, Random Forest and a Multilayer Perceptron. It was possible to successfully predict SAV transmission with 94.4% accuracy. Moreover, it was possible to predict SAV transmission 8 weeks in advance of a 'PD registration' at individual aquaculture salmon farming sites. Important predictors included well boat movement, environmental factors, proximity to sites with a 'PD registration' and seasonality.


Assuntos
Infecções por Alphavirus , Alphavirus , Doenças dos Peixes , Pancreatopatias , Salmo salar , Salmonidae , Animais , Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/veterinária , Aquicultura , Pancreatopatias/veterinária
2.
Food Chem Toxicol ; 111: 341-355, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29102666

RESUMO

A 90-day gavage study was conducted with 0.0, 0.02, 0.075, 0.25, 1.0 and 4.0 mg/kg bw/day dose groups of 3-methylfuran to identify a no-observed adverse effect level for hepatotoxicity and to characterize non-neoplastic effects including changes in gross anatomy, histopathology, clinical biochemistry and hematology. There were significant changes in the serum clinical biochemistry markers related to liver injury where males were more affected than the females for most parameters analysed. The serum liver injury marker γ-glutamyltransferase, alanine and aspartate aminotransferases were significantly increased in males in the 4.0 mg/kg dose group. Alkaline phosphatase was increased in females and males. There were increases in both gross and histological lesions in the liver of both sexes in addition to statistical differences in female liver weights at the 4.0 mg/kg bw/day dose. Significant increases in spleen weights were found in both genders. This was accompanied by a dose-dependent atrophy of both B- and T-cell regions in which the males were more affected. There were no significant changes in male kidney weights but there was microscopically decreased protein in the proximal tubules and crowding of their nuclei in the 4.0 mg/kg bw/day dose group. There were also significant changes in the kidney serum biomarkers including various electrolytes, blood urea nitrogen, creatinine and uric acid. A small, but significant increase in female kidney weights was observed and which increase was accompanied by changes in electrolytes, kidney specific markers and a dose-dependent increase in mineralization. In both genders, amylase decreased whereas lipase increased but these were not accompanied by any histological changes in the pancreas. Histopathological changes in the liver were observed consistently in male and female rats in the 0.25 mg/kg dose group and higher. Hence, a lowest observed adverse effect level (LOAEL) of 0.25 mg/kg bw/d and a no observed adverse effect level (NOAEL) of 0.075 mg/kg bw/day are proposed for 3-methylfuran-induced hepatic lesions in this study. Benchmark dose modelling based on a BMR of 10% change in lesion incidence, generated BMDLs10 of 0.08 mg/kg bw/day in male rats and 0.05-0.17 mg/kg bw/day in female rats for increased incidence of liver lesions.


Assuntos
Poluentes Atmosféricos/toxicidade , Furanos/toxicidade , Testes de Toxicidade Subcrônica/métodos , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Furanos/administração & dosagem , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Baço/efeitos dos fármacos , Baço/patologia
3.
Diabet Med ; 33(2): 235-42, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26036309

RESUMO

AIMS: Artificial pancreas systems show benefit in closely monitored at-home studies, but may not have sufficient power to assess safety during infrequent, but expected, system or user errors. The aim of this study was to assess the safety of an artificial pancreas system emulating the ß-cell when the glucose value used for control is improperly calibrated and participants forget to administer pre-meal insulin boluses. METHODS: Artificial pancreas control was performed in a clinic research centre on three separate occasions each lasting from 10 p.m. to 2 p.m. Sensor glucose values normally used for artificial pancreas control were replaced with scaled blood glucose values calculated to be 20% lower than, equal to or 33% higher than the true blood glucose. Safe control was defined as blood glucose between 3.9 and 8.3 mmol/l. RESULTS: Artificial pancreas control resulted in fasting scaled blood glucose values not different from target (6.67 mmol/l) at any scaling factor. Meal control with scaled blood glucose 33% higher than blood glucose resulted in supplemental carbohydrate to prevent hypoglycaemia in four of six participants during breakfast, and one participant during the night. In all instances, scaled blood glucose reported blood glucose as safe. CONCLUSIONS: Outpatient trials evaluating artificial pancreas performance based on sensor glucose may not detect hypoglycaemia when sensor glucose reads higher than blood glucose. Because these errors are expected to occur, in-hospital artificial pancreas studies using supplemental carbohydrate in anticipation of hypoglycaemia, which allow safety to be assessed in a controlled non-significant environment should be considered as an alternative. Inpatient studies provide a definitive alternative to model-based computer simulations and can be conducted in parallel with closely monitored outpatient artificial pancreas studies used to assess benefit.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemia/prevenção & controle , Sistemas de Infusão de Insulina/efeitos adversos , Pâncreas Artificial/efeitos adversos , Cooperação do Paciente , Complicações Pós-Operatórias/prevenção & controle , Autocuidado , Centros Médicos Acadêmicos , Adulto , Idoso , Glicemia/análise , Boston/epidemiologia , Calibragem , Ritmo Circadiano , Terapia Combinada/efeitos adversos , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/dietoterapia , Dieta para Diabéticos , Humanos , Hiperglicemia/prevenção & controle , Hipoglicemia/epidemiologia , Hipoglicemia/etiologia , Masculino , Refeições , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Reprodutibilidade dos Testes , Risco
5.
Ir J Psychol Med ; 33(4): 217-224, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30115154

RESUMO

OBJECTIVES: Stress control (SC), a brief psycho-education course, was implemented to increase access to psychological therapies in line with Northern Irish mental health service statutory drivers. The first aim of this study was to gauge the efficacy of SC in a robust manner with clinical significance testing. The second aim was to assess whether demographics traditionally 'hard-to-reach' - males, younger adults and those from deprived areas - accessed SC. The third aim was to elucidate what prompted their access and the experiences of attendees at SC. METHODS: Attendees at SC were 170 adults over six iterations of the course. Pre- and post-questionnaires included the Depression Anxiety Stress Scales - 21, captured demographic details and qualitative feedback, which was subject to a mixed-methods analysis. RESULTS: SC attendees reported significant decreases on depression, anxiety and stress sub-scales post-intervention. Moreover, 38.71% (n=36) of attendees who completed SC exhibited clinically significant improvement afterwards on one or more sub-scale. Attendance figures for males, younger adults and those classified as socioeconomically deprived were modest. Patterns within the data suggested prospective success for targeting these cohorts. CONCLUSIONS: SC attracted people in need of mental healthcare input and affected quantifiable change within those people's lives, while satisfying statutory demands for service delivery in an accessible community context. Recommendations to increase engagement with those traditionally 'hard-to-reach' for psychological services are provided, which, if implemented, have the potential to achieve further compliance with Northern Irish mental health statutory drivers.

6.
Cancer Lett ; 345(2): 182-9, 2014 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-23994342

RESUMO

Esophageal adenocarcinoma (EAC) is the eighth most common cancer worldwide, and approximately 15% of patients survive 5years. Reflux disease (GERD) and Barrett's esophagus (BE) are major risk factors for the development of EAC, and epidemiologic studies highlight a strong association with obesity. The immune, inflammatory and intracellular signaling changes resulting from chronic inflammation of the esophageal squamous epithelium are increasingly well characterized. In GERD and Barrett's, an essential role for T-cells in the initiation of inflammation in the esophagus has been identified, and a balance between T-cell responses and phenotype may play an important role in disease progression. Obesity is a chronic low-grade inflammatory state, fueled by adipose tissue derived- inflammatory mediators such as IL-6, TNF-α and leptin, representing a novel area for targeted research. Additionally, reactive oxygen species (ROS) and receptor tyrosine kinase (RTK) activation may drive progression from esophagitis to EAC, and downstream signaling pathways employed by these molecules may be important. This review will explain the diverse range of mechanisms potentially driving and maintaining inflammation within the esophagus and explore both existing and future therapeutic strategies targeting the process.


Assuntos
Adenocarcinoma/etiologia , Esôfago de Barrett/etiologia , Neoplasias Esofágicas/etiologia , Esofagite/complicações , Adenocarcinoma/imunologia , Adenocarcinoma/metabolismo , Animais , Esôfago de Barrett/imunologia , Esôfago de Barrett/metabolismo , Transformação Celular Neoplásica/imunologia , Transformação Celular Neoplásica/metabolismo , Progressão da Doença , Neoplasias Esofágicas/imunologia , Neoplasias Esofágicas/metabolismo , Esofagite/imunologia , Esofagite/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Obesidade/complicações , Obesidade/imunologia , Obesidade/metabolismo , Fatores de Risco , Transdução de Sinais , Linfócitos T/imunologia
7.
Gynecol Oncol ; 132(2): 397-402, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24369301

RESUMO

OBJECTIVE: More patient-centered programming is essential for endometrial cancer (EC) survivors needing to lose weight to reduce cardiovascular disease risk (CVD). The purpose of this study was to improve self-efficacy (SE) and quality of life (QOL) using a lifestyle intervention program designed for weight loss. METHODS: Overweight and obese early-stage EC survivors, n = 75, were randomized into two groups: 1) Survivors of Uterine Cancer Empowered by Exercise and Healthy Diet (SUCCEED), a six-month lifestyle intervention or 2) a usual care group (UC). Participants completed the Weight Efficacy Lifestyle Questionnaire (WEL) to assess SE and the Functional Assessment of Cancer Therapy-General (FACT-G) to measure QOL, and their body mass index (BMI) was calculated at baseline, 3, 6, and 12 months. Mixed, repeated-measures ANCOVA models with baseline covariates were employed using SPSS 20.0. RESULTS: Positive effects in every WEL domain, including the total score, were statistically significant in the SUCCEED group versus the UC group. A linear regression model demonstrated that, if BMI decreased by 1 unit, the total WEL score increased by 4.49 points. Significant negative correlations were found in the total WEL score and a change in BMI of R = -0.356 (p = 0.006). Between-group differences in the FACT-G were significant from baseline in the fatigue domain at three months (p = .008) and in the physical domain at six months (p = .048). No other significant differences were found. CONCLUSION: Overall, this study shows promise for targeted interventions to help improve SE, thus improving BMI.


Assuntos
Neoplasias do Endométrio/psicologia , Neoplasias do Endométrio/reabilitação , Estilo de Vida , Obesidade/terapia , Sobrepeso/terapia , Programas de Redução de Peso/métodos , Índice de Massa Corporal , Feminino , Humanos , Obesidade/psicologia , Sobrepeso/psicologia , Qualidade de Vida , Autoeficácia , Sobreviventes
8.
Clin Otolaryngol ; 37(1): 28-34, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22257443

RESUMO

OBJECTIVES: To determine minimum airflow rate required for olfactory stimulation in successfully rehabilitated laryngectomised patients after learning the polite yawning technique (PYT) and to confirm the hypothesis that sense of smell is rehabilitated once the nasal airflow is re-established. DESIGN: Prospective open interventional trial. SETTING: Tertiary academic hospital. PARTICIPANTS: The study population comprised 100 laryngectomised patients. The control group consisted of 100 non-laryngectomised patients of similar age and sex. Rhinomanometry was used to measure air flow in the right and left nostrils, respectively, while the Smell Diskettes Olfaction test (SDOT) was used to test each individual's sense of smell. MAIN OUTCOME MEASURES: The primary endpoint was increasing the airflow, while the secondary endpoint was improvement in the Smell Diskettes Olfaction test score after learning the polite yawning technique. RESULTS: The difference in the Smell Diskettes Olfaction test results before and after introducing the polite yawning technique was statistically significant (F = 53.077; P < 0.001). The number of accurately identified odours increased with each measurement. There was a significant difference among rhinomanometric measurements of airflow through the right (F = 65.002; P < 0.001) and left nostrils (F = 75.465; P < 0.001). Nasal airflow improved with each measurement. The minimum airflow required for olfactory stimulation in successfully rehabilitated patients was approximately 60 cm(3) /s. The control group had considerably better airflow in both nostrils than the laryngectomised group. The difference between the total number of rehabilitated (normosmic) patients (48%) in the laringectomised group and normosmic participants (56%) in the control group (z = 1.132; P = 0.129) was not statistically significant. CONCLUSION: The number of odours identified by laryngectomised patients increased with the volume of nasal airflow. The number of patients with rehabilitated olfactory function approximated the percentage of normosmic individuals in the non-laryngectomised population. These findings confirm the hypothesis that sense of smell is rehabilitated once the nasal airflow is re-established.


Assuntos
Resistência das Vias Respiratórias , Laringectomia/efeitos adversos , Monitorização Intraoperatória/métodos , Transtornos do Olfato/reabilitação , Rinomanometria/métodos , Olfato/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Laringectomia/reabilitação , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/fisiopatologia , Transtornos do Olfato/etiologia , Transtornos do Olfato/fisiopatologia , Pressão , Estudos Prospectivos , Fatores de Tempo , Adulto Jovem
9.
Cancer Gene Ther ; 19(3): 192-201, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22116377

RESUMO

Tumor necrosis factor superfamily members, including Fas ligand and TRAIL, have been studied extensively for cancer therapy, including as components of gene therapy. We examined the use of FasL expression to achieve tumor-selective replication of an oncolytic poxvirus (vFasL), and explored its biology and therapeutic efficacy for FasR- and FasR+ cancers. Infection of FasR+ normal and MC38 cancer cells by vFasL led to abortive viral replication owing to acute apoptosis and subsequently showed both reduced pathogenicity in non-tumor-bearing mice and reduced efficacy in FasR+ tumor-bearing mice. Infection of FasR- B16 cancer cells by vFasL led to efficient viral replication, followed by late induction of FasR and subsequent apoptosis. Treatment with vFasL as compared with its parental virus (vJS6) led to increased tumor regression and prolonged survival of mice with FasR- cancer (B16) but not with FasR+ cancer (MC38). The delayed induction of FasR by viral infection in FasR- cells provides for potential increased efficacy beyond the limit of the direct oncolytic effect. FasR induction provides one mechanism for tumor-selective replication of oncolytic poxviruses in FasR- cancers with enhanced safety. The overall result is both a safer and more effective oncolytic virus for FasR- cancer.


Assuntos
Proteína Ligante Fas/genética , Terapia Viral Oncolítica/métodos , Poxviridae/fisiologia , Receptor fas/biossíntese , Animais , Apoptose/fisiologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Neoplasias da Mama/virologia , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/terapia , Neoplasias Colorretais/virologia , Proteína Ligante Fas/biossíntese , Proteína Ligante Fas/metabolismo , Feminino , Terapia Genética , Humanos , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Melanoma Experimental/terapia , Melanoma Experimental/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Poxviridae/genética , Replicação Viral , Receptor fas/genética
10.
Toxicol Pathol ; 39(5): 787-94, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21705744

RESUMO

Furan is a heterocyclic organic compound formed during heat treatment for processing and preservation of various types of food. Rodent studies have previously shown that furan is a hepatocarcinogen. Those studies were conducted over a high dose range, which induced tumors at nearly 100% incidence at all doses. This ninety-day gavage study in mice was conducted to extend the dose to a lower range (0.0, 0.03, 0.12, 0.5, 2.0, and 8.0 mg/kg body weight [bw] per day) to identify a no-observed adverse effect level for hepatotoxicity and to characterize non-neoplastic effects, including those affecting clinical biochemistry, hematology, tissue morphology, and histopathology. The liver was the primary target organ with dose-dependent toxicity. Liver weights were increased at the 8.0 mg/kg bw dose in females only. Levels of the serum enzyme alanine transaminase, representative of liver damage, were increased three-fold at the highest dose. Histological changes in the liver were observed at 2.0 and 8.0 mg/kg bw in both sexes. Although clinical parameters were also altered for the kidney, these differences were not accompanied by histological changes. Based on these clinical biochemical and histological changes, a no-observed adverse effect level of 0.12 mg/kg bw per day of furan in mice is suggested.


Assuntos
Furanos/toxicidade , Administração Oral , Animais , Biomarcadores/metabolismo , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Furanos/administração & dosagem , Rim/efeitos dos fármacos , Rim/metabolismo , Testes de Função Renal , Fígado/anatomia & histologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Testes de Função Hepática , Masculino , Camundongos , Camundongos Endogâmicos , Tamanho do Órgão/efeitos dos fármacos , Distribuição Tecidual , Testes de Toxicidade Crônica
11.
Toxicol Pathol ; 38(4): 619-30, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20530249

RESUMO

Rodent studies have shown that furan is a hepatocarcinogen. Previous studies conducted with high doses showed tumors at nearly 100% incidence at all doses. In this paper, a ninety-day gavage experiment conducted with lower doses (0.0, 0.03, 0.12, 0.5, 2.0, and 8.0 mg/kg bw) to identify a no-observed adverse effect level for hepatotoxicity and to characterize non-neoplastic effects including gross changes and histopathology, clinical biochemistry, hematology, and immunotoxicology is reported. As indicated by changes in serum biomarkers, increased liver weights and gross and histological lesions, the liver is the major target organ affected by furan. There were no changes in body weights, food consumption, or histology in other organs. Some of the serum electrolyte markers, including phosphorus, were altered. There was a significant increase in serum thyroxine and triidothyronine in males. This increase was not accompanied by histological thyroid changes. Immunophenotypic analysis showed that thymic lymphocyte maturation was altered in male rats. Although altered clinical biochemistry and hematological parameters were observed at a dose of > 0.5 mg/kg bw, mild histological lesions in the liver were observed at > 0.12 mg/kg bw. Based on this finding, a furan dose of 0.03 mg/kg bw was proposed as the no-observed adverse effect level for hepatic toxicity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Furanos/toxicidade , Fígado/efeitos dos fármacos , Fígado/metabolismo , Análise de Variância , Animais , Biomarcadores/sangue , Plaquetas/metabolismo , Peso Corporal/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Dieta , Feminino , Furanos/administração & dosagem , Histocitoquímica , Incidência , Fígado/patologia , Testes de Função Hepática , Masculino , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Linfócitos T/metabolismo
12.
Gene Ther ; 17(4): 550-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20182517

RESUMO

We have explored a unique combination therapy for metastatic colorectal cancer. This strategy combines a potent and new oncolytic poxvirus expressing a membrane-bound tumor necrosis factor-related apoptosis-inducing ligand (TRAIL or TNFSF10) and oxaliplatin (Ox) chemotherapy. We hypothesized that TRAIL expression would increase the efficacy of the oncolytic poxvirus, and that the therapeutic efficacy would be further enhanced by combination with chemotherapy. The cytotoxicity to cancer cells by Ox, oncolytic vaccinia virus (VV) and trail gene-armed VV alone or in combination was tested in vitro. The trail gene armed oncolytic VV-expressed high levels of TRAIL in infected cancer cells and had greater potency as a cytotoxic agent compared with the parent VV. Ox alone exerted concentration-dependent cytotoxicity. In vitro, the combination of the two agents applied at suboptimal concentrations for individual therapy displayed synergy in inducing cancer cells into enhanced levels of apoptosis/necrosis. Western blot analyses were consistent with the notion that TRAIL induced cancer cell death mainly through apoptosis, whereas Ox and vJS6 induced cell death more through non-apoptotic death pathways. In two aggressive colorectal carcinomatosis models derived from human HCT116 and murine MC38 cells, the combination therapy displayed synergistic or additive antitumor activity and prolonged the survival of the tumor-bearing mice compared with either Ox chemotherapy or vvTRAIL-mediated oncolytic gene therapy alone. This combination strategy may provide a new avenue to treating peritoneal carcinomatosis and other types of metastases of colorectal cancer.


Assuntos
Antineoplásicos/uso terapêutico , Apoptose/genética , Carcinoma/terapia , Neoplasias Colorretais/terapia , Terapia Genética/métodos , Compostos Organoplatínicos/uso terapêutico , Ligante Indutor de Apoptose Relacionado a TNF/genética , Animais , Western Blotting , Carcinoma/tratamento farmacológico , Carcinoma/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Citometria de Fluxo , Humanos , Camundongos , Oxaliplatina , Poxviridae , Transfecção
15.
Br J Pharmacol ; 134(8): 1679-88, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11739244

RESUMO

1. Postnatal mortality in isolated congenital diaphragmatic hernia (CDH) is mainly related to the associated pulmonary hypertension (PH) and to right-to-left shunting. 2. Endothelins (ETs) are potent vasoconstrictors and pro-mitogenic peptides. Strong evidences support their participation in CDH and in the etiology of PH via the activation of ET(A) receptors (ET(A)-Rs). 3. Evaluation of the effect of ABT-627, a selective non-peptidic ET(A)-R antagonist, given from -15 to 210 min post-delivery (1 mg kg(-1) bolus +0.01 mg kg(-1) h(-1) infusion, i.v.), was conducted in the lamb model of CDH. 4. Severity of CDH was assessed in comparison to untreated controls (n=5). Untreated CDH lambs (n=7) had a higher mean pulmonary arterial pressure (MPAP; P<0.0001), lower mean blood pressure (MBP; P=0.0004), higher MPAP / MBP ratio (P<0.0001), lower arterial pH (P<0.0001), higher paCO(2) (P<0.0001), lower paO(2) (P<0.0001) and lower post-ductal pulsatile SaO(2) (P<0.0001) than untreated controls. 5. Treated controls (n=7) showed a higher MPAP, lower MBP, higher MPAP/MBP ratio, lower arterial pH, higher paCO(2), lower paO(2), lower post-ductal pulsatile SaO(2) and lower plasmatic ir-ET ratios compared to untreated controls (P<0.0001). 6. Treated CDH lambs (n=8) showed a higher MBP (P<0.0001), lower MPAP / MBP ratio (P<0.0001), higher arterial pH (P<0.0001), lower paCO(2) (P<0.0001), higher paO(2) (P=0.0228), higher post-ductal pulsatile SaO(2) (P=0.0016) and lower plasmatic ir-ET ratios (P=0.0247) when compared to untreated CDH lambs. 7. These observations revealed that, although acute perinatal treatment with a selective non-peptidic ET(A)-R antagonist had some adverse effects in controls, it attenuated the progressive cardiopulmonary deterioration that occurred after birth in CDH lambs.


Assuntos
Antagonistas dos Receptores de Endotelina , Hérnia Diafragmática/tratamento farmacológico , Hérnia Diafragmática/fisiopatologia , Pirrolidinas/farmacologia , Animais , Animais Recém-Nascidos , Atrasentana , Pressão Sanguínea/efeitos dos fármacos , Feminino , Hemodinâmica/efeitos dos fármacos , Hérnia Diafragmática/etiologia , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/embriologia , Hipertensão Pulmonar/fisiopatologia , Infusões Intravenosas , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/fisiopatologia , Análise por Pareamento , Oxigênio/metabolismo , Gravidez , Troca Gasosa Pulmonar , Pirrolidinas/administração & dosagem , Receptor de Endotelina A , Respiração/efeitos dos fármacos , Ovinos , Fatores de Tempo
17.
Br J Cancer ; 84(9): 1280-5, 2001 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-11336482

RESUMO

The relationship between tumour oxygenation in vivo and metastatic potential was investigated in 2 rodent tumour models, KHT-C fibrosarcoma and SCC-VII squamous cell carcinoma. The oxygen status in these rodent tumours transplanted intramuscularly in syngeneic mice was measured using the Eppendorf pO(2)Histograph. The results indicate a considerable heterogeneity in oxygenation between individual tumours within each tumour cell line. At different tumour sizes, animals were killed and lung lobes were examined for macroscopic and microscopic lung metastases. In the KHT-C tumours, a significant increase in early pulmonary metastasis formation was observed in mice with hypoxic primary tumours. Hypoxic SCC-VII tumours did not give rise to enhanced lung metastasis formation despite oxygenation in a range similar to the KHT-C tumours. However, the overall metastasis incidence in the SCC-VII model was very low. The results obtained in the KHT-C model, which show that hypoxic tumours are more likely to metastasize, are in agreement with recent clinical data suggesting that a hypoxic environment might be implicated in metastatic ability of human tumours.


Assuntos
Carcinoma de Células Escamosas/patologia , Fibrossarcoma/patologia , Hipóxia , Neoplasias Pulmonares/secundário , Animais , Camundongos , Fatores de Risco , Células Tumorais Cultivadas
19.
J Pediatr Surg ; 35(5): 780-4, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10813349

RESUMO

BACKGROUND/PURPOSE: The pathophysiology of congenital diaphragmatic hernia (CDH) associated with lung hypoplasia and pulmonary hypertension is not understood fully. Endothelins (ETs) are the most potent vasoconstrictors that also act as promitogenic agents. They may play a role during pregnancy in leading to the condition found at birth and ongoing mortality in CDH. Therefore, the authors studied the effect of CGS 26303, a nonselective endothelin-converting enzyme and neutral endopeptidase inhibitor, in the rat model of CDH. METHODS: Pregnant Sprague-Dawley rats were divided into 3 groups: group 1 (n = 4) received CGS 26303 (50 mg/kg, subcutaneously, twice a day), from gestational day 12 until term (21 to 23 days); group 2 (n = 8) received nitrofen (100 mg/kg, orally) at gestational day 11.5; group 3 (n = 8) received both nitrofen and CGS 26303. The survival of the newborn rats was monitored up to 240 minutes. After natural death or euthanasia, they were weighed and microdissected. The degree of hernia was quantified as small, moderate, or severe, and lungs and liver were harvested and weighed. RESULTS: Newborn rats from mothers of group 3 (n = 81) survived 196 +/- 8 minutes compared with 173 +/- 9 minutes of those of group 2 (n = 97). Severe CDH from group 3 (n = 20) had a mean survival time of 66 +/- 13 minutes compared with 26 +/- 4 minutes for those of group 2 (n = 27). Lung index in severe CDH pups of group 3 was increased by 13% compared with those from group 2 (P < .0001), whereas their liver index went down by 8% (P < .05). CONCLUSIONS: These results suggest that CGS 26303 might have a beneficial effect when given during pregnancy in increasing survival at birth and reducing the severity of the pulmonary hypoplasia in newborn rats with nitrofen-induced CDH.


Assuntos
Ácido Aspártico Endopeptidases/efeitos dos fármacos , Hérnia Diafragmática/tratamento farmacológico , Organofosfonatos/farmacologia , Inibidores de Proteases/farmacologia , Tetrazóis/farmacologia , Animais , Animais Recém-Nascidos , Ácido Aspártico Endopeptidases/metabolismo , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Enzimas Conversoras de Endotelina , Feminino , Hérnia Diafragmática/induzido quimicamente , Hérnia Diafragmática/classificação , Hérnias Diafragmáticas Congênitas , Injeções Subcutâneas , Modelos Lineares , Fígado/patologia , Pulmão/patologia , Metaloendopeptidases , Tamanho do Órgão/efeitos dos fármacos , Éteres Fenílicos , Gravidez , Modelos de Riscos Proporcionais , Ratos , Valores de Referência , Análise de Sobrevida
20.
Radiat Res ; 152(2): 107-12, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10409318

RESUMO

Hypoxia affects the sensitivity of cells to radiation. Hence there is considerable interest in the development and assessment of techniques for measuring oxygen levels. In the work described here, we explore the use of tumor needle biopsies (fine needle aspirates) in an assay that is standard in the field of radiation biology: the paired survival assay. We found that needle biopsies are a feasible option for estimating cell survival when conducting this assay, and that the variability in cell survival between tumors was greater than that between different biopsies from the same tumor. Using this technique, we then compared measurements of tumor hypoxia using the paired survival assay and the growth delay assay in the same individual tumors. We found a significant correlation between these two techniques.


Assuntos
Hipóxia Celular , Fibrossarcoma/radioterapia , Oxigênio/análise , Animais , Biópsia por Agulha , Sobrevivência Celular/efeitos da radiação , Fibrossarcoma/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C3H , Células Tumorais Cultivadas
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