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1.
Prev Vet Med ; 224: 106095, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38232517

ABSTRACT

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.


Subject(s)
Alphavirus Infections , Alphavirus , Fish Diseases , Pancreatic Diseases , Salmo salar , Salmonidae , Animals , Alphavirus Infections/epidemiology , Alphavirus Infections/veterinary , Aquaculture , Pancreatic Diseases/veterinary
2.
Food Chem Toxicol ; 111: 341-355, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29102666

ABSTRACT

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.


Subject(s)
Air Pollutants/toxicity , Furans/toxicity , Toxicity Tests, Subchronic/methods , Administration, Oral , Animals , Body Weight/drug effects , Dose-Response Relationship, Drug , Female , Furans/administration & dosage , Kidney/drug effects , Kidney/pathology , Liver/drug effects , Liver/pathology , Male , Organ Size/drug effects , Rats , Rats, Inbred F344 , Spleen/drug effects , Spleen/pathology
4.
Diabet Med ; 33(2): 235-42, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26036309

ABSTRACT

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.


Subject(s)
Diabetes Mellitus, Type 1/drug therapy , Hypoglycemia/prevention & control , Insulin Infusion Systems/adverse effects , Pancreas, Artificial/adverse effects , Patient Compliance , Postoperative Complications/prevention & control , Self Care , Academic Medical Centers , Adult , Aged , Blood Glucose/analysis , Boston/epidemiology , Calibration , Circadian Rhythm , Combined Modality Therapy/adverse effects , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/diet therapy , Diet, Diabetic , Humans , Hyperglycemia/prevention & control , Hypoglycemia/epidemiology , Hypoglycemia/etiology , Male , Meals , Middle Aged , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Reproducibility of Results , Risk
5.
Ir J Psychol Med ; 33(4): 217-224, 2016 Dec.
Article in English | MEDLINE | ID: mdl-30115154

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-23994342

ABSTRACT

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.


Subject(s)
Adenocarcinoma/etiology , Barrett Esophagus/etiology , Esophageal Neoplasms/etiology , Esophagitis/complications , Adenocarcinoma/immunology , Adenocarcinoma/metabolism , Animals , Barrett Esophagus/immunology , Barrett Esophagus/metabolism , Cell Transformation, Neoplastic/immunology , Cell Transformation, Neoplastic/metabolism , Disease Progression , Esophageal Neoplasms/immunology , Esophageal Neoplasms/metabolism , Esophagitis/immunology , Esophagitis/metabolism , Humans , Inflammation Mediators/metabolism , Obesity/complications , Obesity/immunology , Obesity/metabolism , Risk Factors , Signal Transduction , T-Lymphocytes/immunology
7.
Gynecol Oncol ; 132(2): 397-402, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24369301

ABSTRACT

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.


Subject(s)
Endometrial Neoplasms/psychology , Endometrial Neoplasms/rehabilitation , Life Style , Obesity/therapy , Overweight/therapy , Weight Reduction Programs/methods , Body Mass Index , Female , Humans , Obesity/psychology , Overweight/psychology , Quality of Life , Self Efficacy , Survivors
8.
Clin Otolaryngol ; 37(1): 28-34, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22257443

ABSTRACT

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.


Subject(s)
Airway Resistance , Laryngectomy/adverse effects , Monitoring, Intraoperative/methods , Olfaction Disorders/rehabilitation , Rhinomanometry/methods , Smell/physiology , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Laryngectomy/rehabilitation , Male , Middle Aged , Nasal Mucosa/physiopathology , Olfaction Disorders/etiology , Olfaction Disorders/physiopathology , Pressure , Prospective Studies , Time Factors , Young Adult
9.
Cancer Gene Ther ; 19(3): 192-201, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22116377

ABSTRACT

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.


Subject(s)
Fas Ligand Protein/genetics , Oncolytic Virotherapy/methods , Poxviridae/physiology , fas Receptor/biosynthesis , Animals , Apoptosis/physiology , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Breast Neoplasms/therapy , Breast Neoplasms/virology , Cell Line, Tumor , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/therapy , Colorectal Neoplasms/virology , Fas Ligand Protein/biosynthesis , Fas Ligand Protein/metabolism , Female , Genetic Therapy , Humans , Melanoma, Experimental/genetics , Melanoma, Experimental/metabolism , Melanoma, Experimental/therapy , Melanoma, Experimental/virology , Mice , Mice, Inbred C57BL , Mice, Nude , Poxviridae/genetics , Virus Replication , fas Receptor/genetics
10.
Toxicol Pathol ; 39(5): 787-94, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21705744

ABSTRACT

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.


Subject(s)
Furans/toxicity , Administration, Oral , Animals , Biomarkers/metabolism , Body Weight/drug effects , Eating/drug effects , Female , Furans/administration & dosage , Kidney/drug effects , Kidney/metabolism , Kidney Function Tests , Liver/anatomy & histology , Liver/drug effects , Liver/metabolism , Liver/pathology , Liver Function Tests , Male , Mice , Mice, Inbred Strains , Organ Size/drug effects , Tissue Distribution , Toxicity Tests, Chronic
11.
Toxicol Pathol ; 38(4): 619-30, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20530249

ABSTRACT

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.


Subject(s)
Chemical and Drug Induced Liver Injury/etiology , Furans/toxicity , Liver/drug effects , Liver/metabolism , Analysis of Variance , Animals , Biomarkers/blood , Blood Platelets/metabolism , Body Weight/drug effects , Chemical and Drug Induced Liver Injury/metabolism , Chemical and Drug Induced Liver Injury/pathology , Diet , Female , Furans/administration & dosage , Histocytochemistry , Incidence , Liver/pathology , Liver Function Tests , Male , No-Observed-Adverse-Effect Level , Organ Size/drug effects , Rats , Rats, Inbred F344 , T-Lymphocytes/metabolism
12.
Gene Ther ; 17(4): 550-9, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20182517

ABSTRACT

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.


Subject(s)
Antineoplastic Agents/therapeutic use , Apoptosis/genetics , Carcinoma/therapy , Colorectal Neoplasms/therapy , Genetic Therapy/methods , Organoplatinum Compounds/therapeutic use , TNF-Related Apoptosis-Inducing Ligand/genetics , Animals , Blotting, Western , Carcinoma/drug therapy , Carcinoma/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , Flow Cytometry , Humans , Mice , Oxaliplatin , Poxviridae , Transfection
15.
Br J Pharmacol ; 134(8): 1679-88, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11739244

ABSTRACT

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.


Subject(s)
Endothelin Receptor Antagonists , Hernia, Diaphragmatic/drug therapy , Hernia, Diaphragmatic/physiopathology , Pyrrolidines/pharmacology , Animals , Animals, Newborn , Atrasentan , Blood Pressure/drug effects , Female , Hemodynamics/drug effects , Hernia, Diaphragmatic/etiology , Hypertension, Pulmonary/drug therapy , Hypertension, Pulmonary/embryology , Hypertension, Pulmonary/physiopathology , Infusions, Intravenous , Lung/drug effects , Lung/metabolism , Lung/physiopathology , Matched-Pair Analysis , Oxygen/metabolism , Pregnancy , Pulmonary Gas Exchange , Pyrrolidines/administration & dosage , Receptor, Endothelin A , Respiration/drug effects , Sheep , Time Factors
17.
Br J Cancer ; 84(9): 1280-5, 2001 May 04.
Article in English | MEDLINE | ID: mdl-11336482

ABSTRACT

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.


Subject(s)
Carcinoma, Squamous Cell/pathology , Fibrosarcoma/pathology , Hypoxia , Lung Neoplasms/secondary , Animals , Mice , Risk Factors , Tumor Cells, Cultured
18.
19.
J Pediatr Surg ; 35(5): 780-4, 2000 May.
Article in English | MEDLINE | ID: mdl-10813349

ABSTRACT

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.


Subject(s)
Aspartic Acid Endopeptidases/drug effects , Hernia, Diaphragmatic/drug therapy , Organophosphonates/pharmacology , Protease Inhibitors/pharmacology , Tetrazoles/pharmacology , Animals , Animals, Newborn , Aspartic Acid Endopeptidases/metabolism , Body Weight/drug effects , Disease Models, Animal , Endothelin-Converting Enzymes , Female , Hernia, Diaphragmatic/chemically induced , Hernia, Diaphragmatic/classification , Hernias, Diaphragmatic, Congenital , Injections, Subcutaneous , Linear Models , Liver/pathology , Lung/pathology , Metalloendopeptidases , Organ Size/drug effects , Phenyl Ethers , Pregnancy , Proportional Hazards Models , Rats , Reference Values , Survival Analysis
20.
Int J Radiat Oncol Biol Phys ; 44(5): 1137-46, 1999 Jul 15.
Article in English | MEDLINE | ID: mdl-10421548

ABSTRACT

PURPOSE: To investigate the relationship between different techniques for measuring oxygen levels in a murine tumor model. METHODS AND MATERIALS: Using the murine fibrosarcoma line KHT-C, five techniques of measuring oxygen levels-the Eppendorf pO2 Histograph, EF5 binding, the comet assay, a paired survival assay, and an in vivo growth delay assay-were assessed. In these experiments, three or more techniques were applied in different combinations to measure the oxygen levels in individual tumors. RESULTS: Statistically significant correlations were observed between the hypoxic proportions calculated from the paired survival assay with those from EF5 binding. The comet assay was found to have a statistically significant correlation with the paired survival analysis and the growth delay analysis. No statistically significant correlation was found between the Eppendorf pO2 Histograph measurements and those from the other techniques, although there were weak correlations with the paired survival assay and EF5 binding. For technical reasons, a comparison was not made between EF5 binding and the growth delay assay. CONCLUSIONS: The correlations found between EF5 binding and the comet assay with the radiobiological assays suggest that these techniques have potential for predicting outcome following radiation treatment. The lack of correlation seen between the pO2 Histograph data and the radiobiological assays is in contrast to results from early clinical trials.


Subject(s)
Biosensing Techniques , Oxygen/analysis , Animals , Cell Hypoxia , Male , Mice , Mice, Inbred C3H , Polarography , Radiobiology , Tumor Cells, Cultured
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