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1.
J Dairy Sci ; 104(2): 2318-2333, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33246610

RESUMO

Estrus traits have economic value in dairy production systems and could be incorporated into genetic selection indices. In an effort to further understand selection responses, 2 studies were performed to estimate the intra- and interclass correlation coefficients for estrus traits. Holstein-Friesian cows (n = 1,197; study 1) across 5 pasture-based grazing dairy herds were fitted with a capacitive touch sensing (CTS) device on the rump (FlashMate, Farmshed Labs Limited, Hamilton, New Zealand). The daily number of rump touches were subjected to a peak detection program to objectively identify periods of increased rump touches above baseline (indicative of estrus). The number of times touched and the sum of the touch duration were used to compare farms and estimate the intraclass correlation (repeatability). For study 2, postpartum Holstein (n = 85) and Guernsey (n = 5) cows in a confinement-style dairy were used. Cows were fitted with an IceQube accelerometer (IceRobotics Ltd., Edinburgh, United Kingdom) to measure steps taken per hour and a CTS device was applied to both rumps. The interclass correlation for the number of rump touches and number of steps taken during estrus was calculated. Data collected from 5 herds (study 1) demonstrated a 2- to 3-fold difference between herds in the number of rump touches and total touch time during estrus. The intraclass correlation (repeatability; estimates of maximum heritability) for rump touches during estrus was 0.22. For study 2, the number of steps and the number of rump touches during estrus increased in a synchronous manner. The intraclass correlation (repeatability) for number of steps during estrus was 0.26. The interclass correlation (r) for the number of rump touches and the number of steps was 0.46 (R2 = 0.21). Based on the R2, at least 20% of the variation in the number of steps during estrus was explained by the number of touches to the rump of the cow. Selecting cows for the number of steps taken during estrus could increase the number of rump touches (mounts, chin rests, and so on, received from other cows) if a genetic correlation exists for the phenotypic correlation that we observed.


Assuntos
Comportamento Animal , Detecção do Estro , Estro/fisiologia , Tato , Animais , Inteligência Artificial , Comportamento Animal/fisiologia , Bovinos , Indústria de Laticínios , Fazendas , Feminino , Lactação , Leite , Nova Zelândia , Período Pós-Parto , Reino Unido
2.
J Dairy Sci ; 104(2): 2445-2454, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33246615

RESUMO

Estrus is an important behavior that can potentially be subjected to genomic selection. Circulating estradiol concentrations at estrus may be a useful phenotype if the absolute concentrations of estradiol are associated with overt phenotypes for estrus (activity, rump touches, or both; e.g., mounts, chinrests) that can be easily observed. The objective was to measure plasma estradiol concentrations at estrus and associate these measurements with the increase in activity (steps per hour) and rump touches received at estrus. We also tested the effect of lactation on the estrus traits that we measured. Cows (n = 11 lactating and n = 9 nonlactating) were treated with PGF2α to synchronize estrus. A jugular vein was cannulated to collect blood every 2 h for plasma estradiol measurement. Plasma LH was measured during the periestrual period to determine the time of the LH surge. Cows were fitted with an accelerometer to measure activity (steps per hour) and a capacitive touch sensing device to measure the number of rump touches and total touch time. Plasma estradiol concentrations were poorly correlated with overt signs of estrus during the period leading up to maximum estrus activity. After peak estrus activity (when cows were going out of estrus and plasma estradiol concentrations were decreasing), a stronger correlation was detected between overt signs of estrus and plasma estradiol concentrations. Effective selection for improved estrus expression based on plasma estradiol concentrations will depend on whether the cow is coming into or going out of estrus at the time of blood sampling. An association existed between lactation and fewer number of hours in estrus when estrus was defined by an increase in activity (steps per hour). Lactating cows had a shorter interval from the onset of estrus to the LH surge, and the shorter interval to the LH surge may have reduced the period of elevated estradiol during estrus in the lactating cows. Understanding mechanisms that control the sensitivity of the cow to estradiol and making appropriate selection decisions based on these mechanisms will likely increase overt signs of estrus in dairy cows.


Assuntos
Bovinos/fisiologia , Estradiol/sangue , Estro/sangue , Animais , Comportamento Animal , Bovinos/sangue , Bovinos/genética , Feminino , Lactação , Fenótipo , Seleção Genética
3.
Colorectal Dis ; 21(6): 663-670, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30742736

RESUMO

AIM: Recent data have suggested near-equivalent oncological results when treating early rectal cancer by local excision followed by radio- ± chemotherapy rather than salvage radical surgery. The aim of this retrospective study was to assess the use of contact X-ray brachytherapy within this paradigm. METHOD: All patients had undergone local excision and were referred to our radiotherapy centre for treatment with contact X-ray brachytherapy. Postoperative (chemo)radiotherapy was also given in their local hospital in most cases. Variables assessed were local excision method, postoperative therapy received, follow-up duration, disease-free survival, salvage surgery and stoma-free survival. RESULTS: In total, 180 patients with a median age of 70 (range 36-99) years were assessed. Following local excision, pT stages were pT1 = 131 (72%), pT2 = 44 (26%), pT3 = 5 (2%). All patients received contact X-ray brachytherapy boosting at our centre and, in addition, 110 received chemoradiotherapy and 60 received radiotherapy alone. After a median follow-up of 36 months (range 6-48), 169 patients (94%) remained free of local recurrence. Of the 11 patients with local recurrence (three isolated nodal), five underwent salvage abdominoperineal excision. Eight patients developed distant disease, of whom five underwent metastasis surgery. At last included follow-up 173 (96%) patients were free of all disease and 170 (94%) were stoma free. CONCLUSIONS: Contact therapy can be offered in addition to external beam radio (±chemo) therapy instead of radical surgery as follow-on treatment after local excision of early rectal cancer. This combination can provide equivalent outcomes to radical surgery. The added value of contact therapy should be formally assessed in a clinical trial.


Assuntos
Braquiterapia/mortalidade , Protectomia/mortalidade , Neoplasias Retais/terapia , Terapia de Salvação/mortalidade , Adulto , Idoso , Braquiterapia/métodos , Quimiorradioterapia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Protectomia/métodos , Radiografia , Neoplasias Retais/mortalidade , Estudos Retrospectivos , Terapia de Salvação/métodos , Resultado do Tratamento
4.
Clin Oncol (R Coll Radiol) ; 30(3): 166-177, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29248311

RESUMO

AIMS: Following chemoradiotherapy in patients with rectal cancer, the addition of contact X-ray brachytherapy (CXB) in partial responders might increase the proportion of patients with a clinical complete response (cCR) and who are thus suitable for watch and wait management. However, the long-term cost-effectiveness of this approach has not been evaluated. MATERIALS AND METHODS: Decision analytical modelling and a Markov simulation were used to compare long-term costs, quality-adjusted life years (QALYs) and cost-effectiveness from a third-party payer (National Health Service) perspective for treatment strategies after chemoradiotherapy; watch and wait with CXB when a cCR was not initially achieved after external beam radiotherapy (EBRT) (WWCXB), watch and wait with EBRT alone (WWEBRT) and radical surgery for all patients. The effect of uncertainty in model parameters and patient demographics was investigated. RESULTS: WWCXB had a higher QALY payoff than both radical surgery and WWEBRT and was less costly in most scenarios and demographic cohorts. In all plausible scenarios, WWCXB was the most cost-effective, at a threshold of £20 000/QALY. This finding was insensitive to uncertainty associated with model parameters. CONCLUSIONS: WWCXB is likely to be cost-effective compared with both WWEBRT alone and radical surgery. These findings support the use of CXB boost as an adjunct to a watch and wait strategy.


Assuntos
Braquiterapia/economia , Neoplasias Retais/economia , Neoplasias Retais/radioterapia , Conduta Expectante/economia , Quimiorradioterapia , Análise Custo-Benefício , Feminino , Humanos , Pessoa de Meia-Idade , Anos de Vida Ajustados por Qualidade de Vida , Neoplasias Retais/tratamento farmacológico
5.
Leukemia ; 31(8): 1779-1787, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27922598

RESUMO

The human EphA3 gene was discovered in a pre-B acute lymphoblastic leukemia (pre-B-ALL) using the EphA3-specific monoclonal antibody (mAb), IIIA4, which binds and activates both human and mouse EphA3. We use two models of human pre-B-ALL to examine EphA3 function, demonstrating effects on pre-B-cell receptor signaling. In therapeutic targeting studies, we demonstrated antitumor effects of the IIIA4 mAb in EphA3-expressing leukemic xenografts and no antitumor effect in the xenografts with no EphA3 expression providing evidence that EphA3 is a functional therapeutic target in pre-B-ALL. Here we show that the therapeutic effect of the anti-EphA3 antibody was greatly enhanced by adding an α-particle-emitting 213Bismuth payload.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Receptor EphA3/imunologia , Animais , Bismuto , Linhagem Celular Tumoral , Humanos , Imunoterapia , Camundongos , Receptor EphA3/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Colorectal Dis ; 18(9): 861-70, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26876570

RESUMO

AIM: Recent data have highlighted the potential of more intensive neoadjuvant protocols to increase and sustain the rate of complete response in rectal cancer managed nonoperatively. This study aimed to review the outcome of all patients from our district general hospitals network who had received standard neoadjuvant therapy and were additionally referred to a centre of excellence for contact X-ray brachytherapy or high-dose-rate brachytherapy boost. METHOD: A retrospective, chart-based review of all patients co-managed in this manner was performed. Patient details were retrieved from a prospectively maintained departmental database. Indications for treatment, patient outcome and serial data from follow-up clinical and radiological assessment were analysed. RESULTS: Seventeen patients treated over a 6-year period were identified. Median follow-up was 20 (5-54) months. Fourteen patients were clinically staged as T2 or T3 and eight were clinically node positive. Three patients died, of whom only one was initially a surgical candidate but refused an exenteration. Of the 14 patients who remain alive, 11 (79%) have a sustained complete (n = 8) or partial (n = 3) response. Two patients had an incomplete response, one is being palliated and the other awaits salvage surgery. One patient underwent abdominoperineal excision for suspected local recurrence. Currently 13 (93%) surviving patients are stoma free. CONCLUSIONS: This series shows that the addition of a radiotherapy boost offered sustained responses and stoma-free survival even in advanced disease and adverse patient populations whilst providing the majority of care closer to home.


Assuntos
Adenocarcinoma/terapia , Antimetabólitos Antineoplásicos/uso terapêutico , Braquiterapia/métodos , Capecitabina/uso terapêutico , Quimiorradioterapia/métodos , Terapia Neoadjuvante , Neoplasias Retais/terapia , Conduta Expectante , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Institutos de Câncer , Feminino , Hospitais de Distrito , Hospitais Gerais , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radioterapia , Neoplasias Retais/patologia , Indução de Remissão , Estudos Retrospectivos
7.
Tech Coloproctol ; 19(3): 159-64, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25687376

RESUMO

BACKGROUND: There is currently no reliable means to restage rectal cancers after neoadjuvant chemoradiation. Recent histological evidence shows that the epicentre for residual cancer cells is focussed directly underneath any residual mucosal abnormality (RMA). This proof-of-concept study aimed to determine the utility of a novel, minimally invasive method of incisional biopsy as a restaging tool. A secondary aim was to compare its performance to clinical response assessment. METHODS: After surgical resection, 0.5 × 0.5 cm, full-thickness incisional biopsy was performed in 15 rectal cancers. Of these, 13 had RMA and 2 had mucosal cCR but a palpable intramural abnormality. In all patients, a full-thickness incisional biopsy was taken through the centre of these areas. The ypT stage of the incisional biopsy and the final total specimen were compared. Complete mucosal clinical response was deemed to have occurred when either no residual tumour or only a flat mucosal scar remained. RESULTS: Incisional biopsy correctly identified all patients that had been downstaged to ypT0; however, it also falsely identified 5 of 10 patients (50%) with yp residual disease as ypT0. Overall performance of incisional biopsy to detect residual cancer was 50% sensitivity, 100 % specificity, 100% PPV, and 50% NPV with an accuracy of 66%. A complete mucosal clinical response occurred in only one of five patients downstaged to ypT0 (20% sensitive). It also occurred in one patient, which was ultimately staged as ypT3. CONCLUSION: This prospective data demonstrates that incisional biopsy is not suitable as a stand-alone method to restage rectal cancer after CRT. Alternate or complementary means of restaging are needed.


Assuntos
Biópsia/métodos , Estadiamento de Neoplasias/métodos , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Reto/patologia , Adulto , Idoso , Quimiorradioterapia Adjuvante , Feminino , Humanos , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasia Residual , Projetos Piloto , Estudos Prospectivos , Sensibilidade e Especificidade
9.
Colorectal Dis ; 16(8): 610-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24593015

RESUMO

AIM: The aim of this study was to determine the distribution of residual tumour within the bowel wall in relation to residual mucosal abnormalities (RMAs) and surrounding normal mucosa in patients with rectal cancer who underwent neoadjuvant chemoradiation followed by curative surgery. METHOD: Archived pathological slides from a cohort of 60 patients with residual tumour were retrieved. The incidence, distance and depth of tumour spread (ypT) under RMAs and adjacent normal mucosa were reviewed and recorded. RESULTS: Histological sections containing both RMA and adjacent normal mucosa were available for 45 of 60 patients with ypT1 (n = 6), ypT2 (n = 18) and ypT3 (n = 21) disease. The maximal depth of invasion, as measured by ypT stage, was found underneath the RMA in 44 of 45 (98%) patients. Microscopic tumour spread lateral to the RMA and under adjacent normal mucosa was found in 32 of 45 (71%) patients. The median and maximum distances of lateral spread for ypT1 tumours were 0 and 4 mm; for ypT2 were 2.5 and 9 mm; and for ypT3 were 4 and 9 mm respectively. CONCLUSION: Lateral tumour spread under normal mucosa adjacent to RMAs is a common finding and extended up to 9 mm in this study. The epicentre for maximum depth of invasion was directly underneath the RMAs in nearly all cases. These data have clinical and technical implications if local excision is to be considered.


Assuntos
Adenocarcinoma/patologia , Adenocarcinoma/terapia , Quimiorradioterapia Adjuvante , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Adenocarcinoma/cirurgia , Terapia Combinada , Feminino , Humanos , Metástase Linfática , Masculino , Terapia Neoadjuvante , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasia Residual , Neoplasias Retais/cirurgia
10.
Br J Surg ; 99(7): 993-1001, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22351592

RESUMO

BACKGROUND: Local excision of rectal cancer after neoadjuvant chemoradiotherapy (CRT) has been proposed as an alternative to radical surgery in selected patients. However, little is known about the significance of the morphological and histological features of residual tumour. METHODS: Patients who had undergone CRT at the authors' institution between 1997 and 2010 were identified. Multiple features were assessed as putative markers of pathological response. These included: gross residual disease, diameter of residual mucosal abnormalities, tumour differentiation, presence of lymphovascular/perineural invasion and lymph node ratio. RESULTS: Data from 220 of 276 patients were suitable for analysis. Diameter of residual mucosal abnormalities correlated strongly with pathological tumour category after CRT (ypT) (P < 0·001). Forty of 42 tumours downstaged to ypT0/1 had residual mucosal abnormalities of 2·99 cm or less after CRT. Importantly, 19 of 31 patients with a complete pathological response had evidence of a residual mucosal abnormality consistent with an incomplete clinical response. The ypT category was associated with both pathological node status after CRT (P < 0·001) and lymph node ratio (P < 0·001). Positive nodes were found in only one of 42 patients downstaged to ypT0/1. The risk of nodal metastases was associated with poor differentiation (P = 0·027) and lymphovascular invasion (P < 0·001). CONCLUSION: In this series, the majority of patients with a complete pathological response did not have a complete clinical response. In tumours downstaged to ypT0/1 after CRT, residual mucosal abnormalities were predominantly small and had a 2 per cent risk of positive nodes, thus potentially facilitating transanal excision. The presence of adverse histological characteristics risk stratified tumours for nodal metastases.


Assuntos
Quimiorradioterapia/métodos , Mucosa Intestinal/patologia , Neoplasias Retais/terapia , Idoso , Transformação Celular Neoplásica/patologia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Invasividade Neoplásica , Neoplasia Residual , Estudos Prospectivos , Neoplasias Retais/patologia , Reto/cirurgia , Fatores de Risco , Carga Tumoral
11.
Br J Surg ; 97(12): 1752-64, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20845400

RESUMO

BACKGROUND: A complete pathological response occurs in 10-30 per cent of patients with locally advanced rectal cancer undergoing neoadjuvant chemoradiotherapy (CRT). The standard of care has been radical surgery with high morbidity risks and the challenges of stomata despite the favourable prognosis. This review assessed minimalist approaches (transanal excision or observation alone) to tumours with a response to CRT. METHODS: A systematic review was performed using PubMed and Embase databases. Keywords included: 'rectal', 'cancer', 'transanal', 'conservative', 'complete pathological response', 'radiotherapy' and 'neoadjuvant'. Original articles from all relevant listings were sourced. These were hand searched for further articles of relevance. Main outcome measures assessed were rates of local recurrence and overall survival, and equivalence to radical surgery. RESULTS: Purely conservative 'watch and wait' strategies after CRT are still controversial. Originally used for elderly patients or those who refused surgery, the data support transanal excision of rectal tumours showing a good response to CRT. A complete pathological response in the T stage (ypT0) indicates < 5 per cent risk of nodal metastases. CONCLUSION: Rectal tumours showing an excellent response to CRT may be suitable for local excision, with equivalent outcomes to radical surgery. This approach should be the subject of prospective clinical trials in specialist centres.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Neoplasias Retais/cirurgia , Reto/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Humanos , Terapia Neoadjuvante , Prognóstico , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/patologia , Neoplasias Retais/radioterapia , Biópsia de Linfonodo Sentinela , Estomas Cirúrgicos , Resultado do Tratamento
12.
Ir J Med Sci ; 179(1): 17-22, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19714393

RESUMO

INTRODUCTION: This study evaluated outcomes for the first 100 bariatric surgical procedures in a single, publicly funded Irish centre. METHODS: This was a retrospective, chart-based study. Demographics and comorbidities of patients, peri- and post-operative outcomes and health benefits obtained by surgery were assessed. RESULTS: In total, 87 patients underwent Roux-en-Y gastric bypass procedures, 11 underwent sleeve gastrectomies and 2 underwent duodenal switch. The first 13 operations were done as open procedures. Of the remaining 87 cases, 85 were started laparoscopically. Postoperatively, 2 laparotomies were performed for bleeding and 2 patients developed incarcerated incisional hernias that required repair. The 30-day readmission rate was 6% of which 2 patients required emergency surgery. There was one postoperative mortality from cardio-respiratory failure. CONCLUSIONS: This series audits the introduction of a publicly funded bariatric service in Ireland and reports a high percentage of procedures completed laparoscopically with an acceptable morbidity and mortality.


Assuntos
Gastroplastia/métodos , Laparoscopia/métodos , Obesidade Mórbida/cirurgia , Adulto , Idoso , Anastomose em-Y de Roux , Feminino , Derivação Gástrica , Gastroplastia/efeitos adversos , Gastroplastia/estatística & dados numéricos , Humanos , Irlanda , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento , Redução de Peso , Adulto Jovem
13.
J Morphol ; 268(11): 967-85, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17702001

RESUMO

Many teleosts including zebrafish, Danio rerio, actively regulate buoyancy with a gas-filled swimbladder, the volume of which is controlled by autonomic reflexes acting on vascular, muscular, and secretory effectors. In this study, we investigated the morphological development of the zebrafish swimbladder together with its effectors and innervation. The swimbladder first formed as a single chamber, which inflated at 1-3 days posthatching (dph), 3.5-4 mm body length. Lateral nerves were already present as demonstrated by the antibody zn-12, and blood vessels had formed in parallel on the cranial aspect to supply blood to anastomotic capillary loops as demonstrated by Tie-2 antibody staining. Neuropeptide Y-(NPY-) like immunoreactive (LIR) fibers appeared early in the single-chambered stage, and vasoactive intestinal polypeptide (VIP)-LIR fibers and cell bodies developed by 10 dph (5 mm). By 18 dph (6 mm), the anterior chamber formed by evagination from the cranial end of the original chamber; both chambers then enlarged with the ductus communicans forming a constriction between them. The parallel blood vessels developed into an arteriovenous rete on the cranial aspect of the posterior chamber and this region was innervated by zn-12-reactive fibers. Tyrosine hydroxylase- (TH-), NPY-, and VIP-LIR fibers also innervated this area and the lateral posterior chamber. Innervation of the early anterior chamber was also demonstrated by VIP-LIR fibers. By 25-30 dph (8-9 mm), a band of smooth muscle formed in the lateral wall of the posterior chamber. Although gas in the swimbladder increased buoyancy of young larvae just after first inflation, our results suggest that active control of the swimbladder may not occur until after the formation of the two chambers and subsequent development and maturation of vasculature, musculature and innervation of these structures at about 28-30 dph.


Assuntos
Sacos Aéreos/crescimento & desenvolvimento , Sacos Aéreos/inervação , Peixe-Zebra/crescimento & desenvolvimento , Fibras Adrenérgicas/ultraestrutura , Sacos Aéreos/irrigação sanguínea , Sacos Aéreos/ultraestrutura , Animais , Vasos Sanguíneos/crescimento & desenvolvimento , Fibras Colinérgicas/ultraestrutura , Feminino , Estágios do Ciclo de Vida/fisiologia , Masculino , Desenvolvimento Muscular/fisiologia , Músculos/inervação , Peixe-Zebra/fisiologia
14.
Cytogenet Genome Res ; 113(1-4): 279-91, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16575191

RESUMO

A small sub-set of mammalian genes are subject to regulation by genomic imprinting such that only one parental allele is active in at least some sites of expression. Imprinted genes have diverse functions, notably including the regulation of growth. Much attention has been devoted to the insulin-like growth factor signalling pathway that has a major influence on fetal size and contains two components encoded by the oppositely imprinted genes, Igf2 (a growth promoting factor expressed from the paternal allele) and Igf2r (a growth inhibitory factor expressed from the maternal allele). These genes fit the parent-offspring conflict hypothesis for the evolution of genomic imprinting. Accumulated evidence indicates that at least one other fetal growth pathway exists that has also fallen under the influence of imprinting. It is clear that not all components of growth regulatory pathways are encoded by imprinted genes and instead it may be that within a pathway the influence of a single gene by each of the parental genomes may be sufficient for parent-offspring conflict to be enacted. A number of imprinted genes have been found to influence energy homeostasis and some, including Igf2 and Grb10, may coordinate growth with glucose-regulated metabolism. Since perturbation of fetal growth can be correlated with metabolic disorders in adulthood these imprinted genes are considered as candidates for involvement in this phenomenon of fetal programming.


Assuntos
Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica , Impressão Genômica , Transtornos do Crescimento/genética , Metabolismo/genética , Animais , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Camundongos , Camundongos Knockout , Síndrome
15.
Eur J Surg Oncol ; 32(1): 55-64, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16324817

RESUMO

AIMS: The prediction of sensitivity and resistance to neoadjuvant therapy has great potential value for many tumour sites. A neoadjuvant regimen is increasingly the gold standard in rectal cancer management and the aim of this review was to highlight predictive markers currently assessed and evaluate their clinical utility. METHODS: A systematic search of Medline was conducted using the following keywords 'colorectal', 'neoadjuvant', 'molecular', 'predict' and 'radiotherapy'. Original manuscripts from all relevant listings were sourced. These were hand searched for further articles of relevance. RESULTS: Conventional indices including tumour stage and grade were unable to predict histological response. Immunohistochemical assessment of P53 gene, Bcl 2, Bax and microsatellite instability are of no predictive value. Studies utilising molecular response predictors from archival pre-treatment tumour tissues have identified several promising predictive markers including p21, spontaneous apoptosis and direct sequencing of the p53 gene. Global gene expression from fresh pre-treatment tissue using cDNA microarray has only recently been assessed but identified expression differences between 54 genes and was able to predict response with 78% sensitivity and 86% specificity. CONCLUSIONS: Currently there are no clinically useful predictors of response based on standard pathological assessment and immunocytochemistry. Direct gene sequencing of p53, studies of apoptosis and global gene sequencing may hold promise.


Assuntos
Biomarcadores Tumorais/metabolismo , DNA de Neoplasias/genética , Genes bcl-2/fisiologia , Genes p53/fisiologia , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Biomarcadores Tumorais/genética , Expressão Gênica , Humanos , Terapia Neoadjuvante , Estadiamento de Neoplasias , Radioterapia Adjuvante , Neoplasias Retais/metabolismo , Neoplasias Retais/patologia , Resultado do Tratamento
16.
Colorectal Dis ; 7(6): 563-70, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16232236

RESUMO

INTRODUCTION: The resolution of pouchitis with metronidazole points to an anaerobic aetiology. Pouchitis is mainly seen in patients with ulcerative colitis pouches (UCP). We have recently found that sulphate reducing bacteria (SRB), a species of strict anaerobe, colonize UCP exclusively. Herein, we aimed to correlate levels of different bacterial species (including SRB) with mucosal inflammation and morphology. METHODS: Following ethical approval, fresh faecal samples and mucosal biopsies were taken from 9 patients with UCP and 5 patients with familial adenomatous polyposis pouches (FAPP). For the purposes of comparison, faecal samples and mucosal biopsies were also taken from the stomas of 7 of the 9 patients with UC (UCS). Colonization by four types of strict anaerobes (SRB, Clostridium perfringens, Bifidobacteria and Bacteroides) as well as by three types of facultative anaerobes (Enterococci, Coliforms and Lactobacilli) was evaluated. Inflammatory scores and mucosal morphology were assessed histologically in a blinded fashion by a pathologist. RESULTS: In general, strict anaerobes predominated over facultative in the UCP (P = 0.041). SRB were present in UCP exclusively. Even after exclusion of SRB from total bacterial counts, strict anaerobes still predominated. In the UCS, facultative anaerobes predominated. Strict and facultative anaerobes were present at similar levels in the FAPP. Enterococci were present at significantly reduced levels in the UCP when compared with the UCS (P = 0.031). When levels of SRB and other anaerobic species were individually correlated with mucosal inflammation and morphology, no trends were observed. CONCLUSION: We have previously identified that SRB exclusively colonize UCP. In addition we have now identified a novel increase in the strict/facultative anaerobic ratio within the UCP compared to UCS. These stark differences in bacterial colonization, however, appear to have limited impact on mucosal inflammation or morphology.


Assuntos
Bacteroides/isolamento & purificação , Bifidobacterium/isolamento & purificação , Clostridium perfringens/isolamento & purificação , Mucosa Intestinal/patologia , Pouchite/microbiologia , Pouchite/patologia , Polipose Adenomatosa do Colo/cirurgia , Colite Ulcerativa/cirurgia , Feminino , Humanos , Masculino
17.
Int Angiol ; 24(2): 199-201, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15997225

RESUMO

Patients who have had multiple previous attempts at limb salvaging surgery frequently go on to have an amputation. This, however, results both in psychological perturbation for the patient and high rehabilitation costs for the community. Successful limb salvage surgery therefore has an important role in vascular surgery. We describe the management of a patient with critical limb ischemia that had previously undergone multiple limb salvage procedures and whose limb was saved by the use of a continuous femoropopliteal crossover bypass graft. The patient, who may have been deemed by some as a candidate for amputation, has full use of his limb 6 months after surgery with ankle brachial pressure index readings of 0.6. Continuous femoropopliteal crossover bypass grafting is a poorly described surgical technique that may be appropriate in a subgroup of patients and may allow salvage of a limb that otherwise may have been deemed fit for amputation.


Assuntos
Arteriopatias Oclusivas/cirurgia , Artéria Femoral/cirurgia , Isquemia/cirurgia , Perna (Membro)/irrigação sanguínea , Dor , Artéria Poplítea/cirurgia , Idoso , Humanos , Masculino , Procedimentos Cirúrgicos Vasculares/métodos
20.
Water Sci Technol ; 46(9): 47-54, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12448451

RESUMO

Some of the many tools used for watershed management are mathematical and computer models for wasteload allocations. QUAL2E is one of the most popular water quality models used for such purposes. The question arises as to whether the model is applicable in a different climate such as that in the tropics. In this study, QUAL2E was used to model Sg. Selangor River in Malaysia using the predictive equations for reaeration coefficient (k2) within the model and the measured reaeration coefficients for the river. The study results indicated that use of the reaeration coefficient (k2) measured at Sg. Selangor River did give the lowest standard error (SE) for the simulation of water quality during the 7Q10 low-flow period which is considered as the worst scene scenario in water quality modeling. But during calibration and validation using actual low-flow discharge data, the measured reaeration coefficients did not give the lowest standard error (SE). In conclusion, the results indicated that QUAL2E is applicable in tropical rivers when used with the modeled river parameters (i.e. hydraulic parameters, meteorological conditions etc.). Measured reaeration coefficients produced good results and several predictive equations also produced comparatively good results.


Assuntos
Modelos Teóricos , Poluentes da Água/análise , Abastecimento de Água/normas , Previsões , Controle de Qualidade , Clima Tropical
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