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1.
J Natl Cancer Inst ; 107(1): 353, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25515230

RESUMO

Cancer research is drawing on the human genome project to develop new molecular-targeted treatments. This is an exciting but insufficient response to the growing, global burden of cancer, particularly as the projected increase in new cases in the coming decades is increasingly falling on developing countries. The world is not able to treat its way out of the cancer problem. However, the mechanistic insights from basic science can be harnessed to better understand cancer causes and prevention, thus underpinning a complementary public health approach to cancer control. This manuscript focuses on how new knowledge about the molecular and cellular basis of cancer, and the associated high-throughput laboratory technologies for studying those pathways, can be applied to population-based epidemiological studies, particularly in the context of large prospective cohorts with associated biobanks to provide an evidence base for cancer prevention. This integrated approach should allow a more rapid and informed translation of the research into educational and policy interventions aimed at risk reduction across a population.


Assuntos
Saúde Global , Comunicação Interdisciplinar , Neoplasias/prevenção & controle , Neoplasias/terapia , Pesquisa Translacional Biomédica , Países Desenvolvidos , Países em Desenvolvimento , Detecção Precoce de Câncer , Medicina Baseada em Evidências , Saúde Global/estatística & dados numéricos , Humanos , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Apoio à Pesquisa como Assunto , Pesquisa Translacional Biomédica/tendências
2.
J Urol ; 186(3): 1128-33, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21784484

RESUMO

PURPOSE: Several studies suggest that hypoxia of the bladder wall contributes to bladder dysfunction but the exact relation between bladder function and blood oxygen saturation, a surrogate marker for hypoxia, is not known. We determined bladder wall blood oxygen saturation in vivo in an animal model of bladder outlet obstruction to establish the exact relation between blood oxygen saturation and bladder function. MATERIALS AND METHODS: In 8 sham operated and 8 urethrally obstructed guinea pigs we measured blood oxygen saturation of the bladder wall by differential path length spectroscopy before surgery and 8 weeks postoperatively. Urodynamic investigations performed during the whole 8-week period provided data on bladder function. RESULTS: Before surgery and 8 weeks after sham surgery blood oxygen saturation in the bladder wall was between 88% and 95% during filling. It decreased during voiding and returned to greater than 90% within 30 seconds. Eight weeks after obstruction saturation was significantly lower than in the sham operated group during filling and voiding. The decrease was positively related to bladder pressure during filling and voiding, and was more pronounced when overactivity was present. Local bladder contractions occurred without a measurable increase in bladder pressure but were associated with a decrease in saturation. CONCLUSIONS: A normal bladder maintains a high oxygen saturation level during filling. Bladder obstruction compromises this ability, especially when it involves overactivity. Local bladder contractions without a measurable increase in bladder pressure were associated with a decrease in blood saturation.


Assuntos
Oxigênio/metabolismo , Obstrução do Colo da Bexiga Urinária/metabolismo , Bexiga Urinária Hiperativa/metabolismo , Bexiga Urinária/metabolismo , Animais , Cobaias , Masculino , Obstrução do Colo da Bexiga Urinária/complicações , Bexiga Urinária Hiperativa/complicações
3.
Cancer Epidemiol Biomarkers Prev ; 19(4): 923-6, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20332270

RESUMO

BACKGROUND: Today's translational cancer research increasingly depends on international multi-center studies. Biobanking infrastructure or comprehensive sample exchange platforms to enable networking of clinical cancer biobanks are instrumental to facilitate communication, uniform sample quality, and rules for exchange. METHODS: The Organization of European Cancer Institutes (OECI) Pathobiology Working Group supports European biobanking infrastructure by maintaining the OECI-TuBaFrost exchange platform and organizing regular meetings. This platform originated from a European Commission project and is updated with knowledge from ongoing and new biobanking projects. This overview describes how European biobanking projects that have a large impact on clinical biobanking, including EuroBoNeT, SPIDIA, and BBMRI, contribute to the update of the OECI-TuBaFrost exchange platform. RESULTS: Combining the results of these European projects enabled the creation of an open (upon valid registration only) catalogue view of cancer biobanks and their available samples to initiate research projects. In addition, closed environments supporting active projects could be developed together with the latest views on quality, access rules, ethics, and law. CONCLUSIONS: With these contributions, the OECI Pathobiology Working Group contributes to and stimulates a professional attitude within biobanks at the European comprehensive cancer centers. IMPACT: Improving the fundamentals of cancer sample exchange in Europe stimulates the performance of large multi-center studies, resulting in experiments with the desired statistical significance outcome. With this approach, future innovation in cancer patient care can be realized faster and more reliably.


Assuntos
Neoplasias , Bancos de Tecidos/organização & administração , Pesquisa Translacional Biomédica/organização & administração , Academias e Institutos/organização & administração , Europa (Continente) , Humanos , Estudos Multicêntricos como Assunto , Patologia Clínica/métodos , Patologia Clínica/organização & administração , Patologia Clínica/normas , Manejo de Espécimes/métodos , Manejo de Espécimes/normas , Bancos de Tecidos/normas , Pesquisa Translacional Biomédica/métodos , Pesquisa Translacional Biomédica/normas
4.
J Sex Med ; 6(7): 1908-13, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19453915

RESUMO

INTRODUCTION: External beam radiotherapy for prostate cancer leads to erectile dysfunction in 36%-43% of patients. The underlying mechanism is largely unknown, although some clinical studies suggest that the arterial supply to the corpora cavernosa is responsible. Two animal experimental studies reported on the effects of a single fraction of prostate irradiation on the penile structures. However, irradiation in multiple fractions is more representative of the actual clinical treatment. AIM: The present prospective, controlled study was initiated to investigate the effect of fractionated prostate irradiation on the arteries of the corpora cavernosa. MAIN OUTCOME MEASURES: Histological evaluation of the penile tissue in comparison with control rats at 2, 4, and 9 weeks after irradiation. METHODS: The prostate of twelve rats was treated with external beam radiation in 5 daily fractions of 7.4 gray. Three control rats were treated with sham irradiation. Prostatic and penile tissue was evaluated for general histology (hematoxylin-eosin). The penile tissue was further evaluated after combined staining for collagen (resorcin fuchsin) and alpha-smooth muscle actin (SMA) (Biogenex). RESULTS: The prostate showed adequate irradiation with fibrosis occurring at 9 weeks after irradiation. The corpora cavernosa showed arteries that had developed loss of smooth muscle cells expressing SMA, thickening of the intima, and occlusions. All the control rats maintained normal anatomy. CONCLUSION: This is the first animal experimental study that demonstrates changes in the arteries of the corpora cavernosa after fractionated irradiation to the prostatic area. The preliminary data suggests that erectile dysfunction after radiotherapy might be caused by radiation damage to the arterial supply of the corpora cavernosa.


Assuntos
Artérias/efeitos da radiação , Endotélio Vascular/efeitos da radiação , Fibrose/etiologia , Músculo Liso/efeitos da radiação , Pênis/irrigação sanguínea , Próstata/irrigação sanguínea , Animais , Fracionamento da Dose de Radiação , Masculino , Pênis/efeitos da radiação , Projetos Piloto , Estudos Prospectivos , Próstata/efeitos da radiação , Ratos , Ratos Sprague-Dawley
5.
Neurourol Urodyn ; 27(5): 454-60, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18288702

RESUMO

AIMS: To determine if detrusor glycogen content in a bladder after removal of a urethral obstruction reflects the situation of bladder dysfunction as it existed during the period of obstruction. METHODS: The glycogen content of the detrusor was scored using a Periodic Acid Schiff's (PAS) staining. It was related to the functional history of the bladder. Bladder tissue was obtained from a guinea-pig model for posterior urethral valves where animals had been obstructed for up to 10 weeks, de-obstructed and allowed to recover for 2--8 weeks. Bladder urodynamic function had been documented with multiple measurements for the complete period of obstruction and de-obstruction. RESULTS: The degree of glycogen deposition in a bladder after de-obstruction correlated directly with bladder function during obstruction. The strongest glycogen deposition was found in bladders having experienced the highest pressures, most instabilities, lowest compliance and highest contractility. In contrast, the bladder glycogen content was not related to the function of the bladder at the day the tissue was obtained, except for a relation between high glycogen content and continuing low compliance. CONCLUSIONS: The glycogen content of a bladder reflects the history of bladder dysfunction, also when measured during a recovery period. This window on the functional history of a bladder may be of clinical value for picking out potential bad-responders to therapy in patients with incomplete data on bladder function during a previous period of bladder obstruction.


Assuntos
Glicogênio/metabolismo , Músculo Liso/metabolismo , Obstrução do Colo da Bexiga Urinária/metabolismo , Obstrução do Colo da Bexiga Urinária/fisiopatologia , Bexiga Urinária/metabolismo , Animais , Cobaias , Técnicas In Vitro , Isquemia/patologia , Isquemia/fisiopatologia , Músculo Liso/patologia , Músculo Liso/fisiopatologia , Reação do Ácido Periódico de Schiff , Uretra/patologia , Uretra/fisiopatologia , Obstrução do Colo da Bexiga Urinária/cirurgia , Urodinâmica/fisiologia
6.
J Urol ; 178(4 Pt 2): 1807-12, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17707007

RESUMO

PURPOSE: Oxybutynin is used clinically to lower intravesical pressure and detrusor overactivity. In vitro it inhibits stretch induced bladder smooth muscle cell proliferation. We tested whether oxybutynin also prevents hypertrophic bladder changes in vivo in a model of partial bladder obstruction. MATERIALS AND METHODS: Subvesical obstruction was induced in immature guinea pigs by a silver ring around the urethra. Eight animals received 0.4 mg oxybutynin per kg body weight per day in 2 doses. Control groups were obstructed without oxybutynin treatment or sham operated. Urodynamic pressure flow studies were performed at 1-week intervals for 10 weeks in all animals under anesthesia with ketamine/xylazine. After 10 weeks the animals were sacrificed and the bladder was removed for structural analysis with periodic acid-Schiff stain, in which the number of glycogen granules was also scored as a measure of previous ischemia. RESULTS: Compared to the sham treated group obstructed animals had significantly higher intravesical pressure and detrusor overactivity, lower compliance and increased contractility. Obstructed animals that received oxybutynin retained normal intravesical pressure, detrusor overactivity and compliance. Their bladder contractility increased as in obstructed animals. The oxybutynin group showed less collagen infiltration in the detrusor and fewer glycogen granules compared to those in obstructed animals. CONCLUSIONS: Our results demonstrate that oxybutynin has a protective effect on bladder function and structure. Prevention of hypertrophic and ischemic bladder changes is an argument for an early start of oxybutynin treatment in children with inborn neurogenic bladder dysfunction, such as spina bifida, or in patients with urethral valves.


Assuntos
Ácidos Mandélicos/farmacologia , Parassimpatolíticos/farmacologia , Obstrução do Colo da Bexiga Urinária/tratamento farmacológico , Animais , Modelos Animais de Doenças , Cobaias , Obstrução do Colo da Bexiga Urinária/patologia , Urodinâmica
7.
BJU Int ; 100(4): 846-52, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17662080

RESUMO

OBJECTIVE: To assess the relationship between glycogen content in bladder detrusor tissue and historical bladder function in a guinea-pig model of partial bladder outlet obstruction (PBOO). MATERIALS AND METHODS: In male immature guinea pigs PBOO was created with a silver ring around the proximal urethra; a control group had a sham operation for comparison. Longitudinal individual urodynamic data were obtained weekly, so that guinea pigs were killed at different levels of bladder dysfunction. Bladder sections were stained with periodic acid-Schiff (PAS) to assess overall morphology and glycogen granule density, scored from 0 (no glycogen) to 3. Glycogen scores were related to both the end-stage and historical extremes of bladder function values. RESULTS: Glycogen granules were seen only in the detrusor; as their number increased their location expanded from only close to the serosa (glycogen score 1), through the detrusor (score 2) up to the urothelium (score 3). A glycogen score of 0 correlated with normal values for all urodynamic variables. Compared with a glycogen score of 0 a score of 1 correlated with significant (P < 0.05) changes in end-stage compliance (decrease) and contractility (increase) and significantly higher historical values for contractility, pressure and number of unstable contractions (NUC). In the group with a glycogen score of 2 there were significant changes in both the end-stage values and historical extremes for compliance, pressure, contractility and NUC (all P < 0.05). In the group with a glycogen score of 3 all these changes were even more dramatic, except for the end-stage contractility, for which the increase was not significant. From glycogen score 0 to score 3 all changes increased in magnitude. CONCLUSION: A high glycogen content reflects a history of abnormal urodynamic function. This finding exemplifies the added value of structural analysis to urodynamic studies. Further studies are needed to relate bladder structure to the potential for functional recovery.


Assuntos
Glicogênio/metabolismo , Obstrução Uretral/fisiopatologia , Obstrução do Colo da Bexiga Urinária/fisiopatologia , Urodinâmica/fisiologia , Animais , Modelos Animais de Doenças , Cobaias , Masculino
8.
J Urol ; 178(3 Pt 1): 1097-103, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17644134

RESUMO

PURPOSE: We determined whether nephrocalcinosis is common and whether its detection is influenced by renal tissue processing. MATERIALS AND METHODS: Renal cortical and papillary tissue was obtained from the unaffected parts of 15 kidneys removed due to an oncological indication. The effect of tissue processing on the loss of crystals was studied in a kidney with nephrocalcinosis due to chronic pyelonephritis. Immediately frozen and formaldehyde fixed sections were analyzed by polarized light and Raman spectroscopy, and stained for calcium (Yasue) and hyaluronan. RESULTS: Although 13 of 15 snap-frozen sections from tumor kidneys contained birefringent particles (mean +/- SD 3.2 +/- 2.9 particles per cm(2)) in the renal tubules, this was not considered nephrocalcinosis because the crystals were not attached to the epithelial lining. Interstitial nephrocalcinosis was found on Yasue stain in 3 of 15 kidneys with tumor (20%). Calcium deposits were found in the papillary interstitium only, always together with hyaluronan. Formaldehyde fixed sections from the pyelonephritis kidney contained fewer renal tubular cell associated birefringent particles than immediately frozen sections (9.4 +/- 1.9 vs 41.6 +/- 1.2 per cm(2)). Particles were composed of calcium oxalate monohydrate (Yasue and Raman). CONCLUSIONS: There are 2 distinct forms of nephrocalcinosis, including tubular nephrocalcinosis, which seems to be reserved for specific conditions such as chronic pyelonephritis, and interstitial nephrocalcinosis. The incidence of tubular calcium oxalate nephrocalcinosis could be underestimated due to the loss of crystals during tissue processing for routine histology. The crystal binding molecule hyaluronan may have a role in the 2 forms of nephrocalcinosis.


Assuntos
Córtex Renal/patologia , Medula Renal/patologia , Nefrocalcinose/patologia , Feminino , Secções Congeladas , Técnicas Histológicas , Humanos , Pessoa de Meia-Idade , Análise Espectral Raman , Difração de Raios X
9.
Anal Chem ; 78(22): 7761-9, 2006 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17105169

RESUMO

We have applied Raman spectroscopy to discriminate between nontumor and tumor bladder tissue and to determine the biochemical differences therein. Tissue samples from 15 patients were collected, and frozen sections were made for Raman spectroscopy and histology. Twenty-five pseudocolor Raman maps were created in which each color represents a cluster of spectra measured on tissue areas of similar biochemical composition. For each cluster, the cluster-averaged spectrum (CAS) was calculated and classified as tumor and nontumor in accordance to pathohistology. Unguided hierarchical clustering was applied to display heterogeneity between and within groups of nontumor and tumor CAS. A linear discriminant analysis model was developed to discriminate between CAS from tumor and nontumor. The model was tested by a leave-one-patient-out validation, 84 of the 90 CAS (93%) were correctly classified with 94% sensitivity and 92% specificity. Biochemical differences between tumor and nontumor CAS areas were analyzed by fitting spectra of pure compounds to the CAS. Nontumor CAS showed higher collagen content while tumor CAS were characterized by higher lipid, nucleic acid, protein, and glycogen content. Raman spectroscopy enabled effective discrimination between tumor and nontumor bladder tissue based on characterized biochemical differences, despite heterogeneity expressed in both tumor and nontumor CAS.


Assuntos
Análise Espectral Raman/métodos , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/patologia , Análise por Conglomerados , Colágeno/análise , Análise Discriminante , Secções Congeladas , Glicogênio/análise , Humanos , Modelos Lineares , Lipídeos/análise , Modelos Biológicos , Ácidos Nucleicos/análise , Proteínas/análise , Sensibilidade e Especificidade
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