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1.
BMC Pharmacol Toxicol ; 22(1): 9, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33509280

RESUMO

BACKGROUND: Emodin, a natural anthraquinone, has shown potential as an effective therapeutic agent in the treatment of many diseases including cancer. However, its clinical development is hindered by uncertainties surrounding its potential toxicity. The primary purpose of this study was to uncover any potential toxic properties of emodin in mice at doses that have been shown to have efficacy in our cancer studies. In addition, we sought to assess the time course of emodin clearance when administered both intraperitoneally (I.P.) and orally (P.O.) in order to begin to establish effective dosing intervals. METHODS: We performed a subchronic (12 week) toxicity study using 3 different doses of emodin (~ 20 mg/kg, 40 mg/kg, and 80 mg/kg) infused into the AIN-76A diet of male and female C57BL/6 mice (n = 5/group/sex). Body weight and composition were assessed following the 12-week feeding regime. Tissues were harvested and assessed for gross pathological changes and blood was collected for a complete blood count and evaluation of alanine transaminase (ALT), aspartate transaminase (AST) and creatinine. For the pharmacokinetic study, emodin was delivered intraperitoneally I.P. or P.O. at 20 mg/kg or 40 mg/kg doses to male and female mice (n = 4/group/sex/time-point) and circulating levels of emodin were determined at 1, 4 and 12 h following administration via liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis. RESULTS: We found that 12 weeks of low (20 mg/kg), medium (40 mg/kg), or high (80 mg/kg) emodin feeding did not cause pathophysiological perturbations in major organs. We also found that glucuronidated emodin peaks at 1 h for both I.P. and P.O. administered emodin and is eliminated by 12 h. Interestingly, female mice appear to metabolize emodin at a faster rate than male mice as evidenced by greater levels of glucuronidated emodin at the 1 h time-point (40 mg/kg for both I.P. and P.O. and 20 mg/kg I.P.) and the 4-h time-point (20 mg/kg I.P.). CONCLUSIONS: In summary, our studies establish that 1) emodin is safe for use in both male and female mice when given at 20, 40, and 80 mg/kg doses for 12 weeks and 2) sex differences should be considered when establishing dosing intervals for emodin treatment.


Assuntos
Antineoplásicos/toxicidade , Emodina/toxicidade , Inibidores de Proteínas Quinases/toxicidade , Animais , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Colo/anatomia & histologia , Colo/efeitos dos fármacos , Emodina/sangue , Emodina/farmacocinética , Feminino , Glucuronídeos/metabolismo , Coração/anatomia & histologia , Coração/efeitos dos fármacos , Intestino Delgado/anatomia & histologia , Intestino Delgado/efeitos dos fármacos , Rim/anatomia & histologia , Rim/efeitos dos fármacos , Fígado/anatomia & histologia , Fígado/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Inibidores de Proteínas Quinases/sangue , Inibidores de Proteínas Quinases/farmacocinética , Caracteres Sexuais , Baço/anatomia & histologia , Baço/efeitos dos fármacos , Testes de Toxicidade Subcrônica
2.
Colorectal Dis ; 19(9): O350-O357, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28688203

RESUMO

AIM: We aimed to determine colorectal length with the 3D-Transit system by describing a 'centreline' of capsule movement and comparing it with known anatomy, as determined by magnetic resonance imaging (MRI). Further, we aimed to test the day-to-day variation of colorectal length assessed with the system. METHOD: The 3D-Transit system consists of electromagnetic capsules that can be tracked as they traverse the gastrointestinal tract. Twenty-five healthy subjects were examined with both 3D-Transit and MRI. Another 21 healthy subjects were examined with 3D-Transit on two consecutive days. RESULTS: Computation of colorectal length from capsule passage was possible for 60 of the 67 3D-Transit recordings. The length of the colorectum measured with MRI and 3D-Transit was 95 (75-153) cm and 99 (77-147) cm, respectively (P = 0.15). The coefficient of variation (CV) between MRI and 3D-Transit was 7.8%. Apart from the caecum/ascending colon being 26% (P = 0.002) shorter on MRI, there were no other differences in total or segmental colorectal lengths between methods (all P > 0.05). The length of the colorectum measured with 3D-Transit on two consecutive days was 102 (73-119) cm and 103 (75-123) cm (P = 0.67). The CV between days was 7.3%. CONCLUSION: The 3D-Transit system allows accurate and reliable determination of colorectal length compared with MRI-derived colorectal length and between days. Antegrade or retrograde capsule movement relative to this centreline, as well as the length and speed of movements, may be determined by future studies to allow better classification and treatment in patients with dysmotility.


Assuntos
Endoscopia por Cápsula , Colo/anatomia & histologia , Técnicas de Diagnóstico do Sistema Digestório/instrumentação , Imageamento por Ressonância Magnética/métodos , Imãs , Adulto , Colo/diagnóstico por imagem , Colo/fisiologia , Feminino , Trânsito Gastrointestinal , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Reprodutibilidade dos Testes
3.
Dan Med J ; 64(2)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28157065

RESUMO

Surgery is the most important factor for radical treatment of colon cancer, and the long-term prognosis can be improved by improving the surgical treatment without increased risk of perioperative mortality. Complete mesocolic excision (CME), in which more extensive lymph node (LN) dissection is performed, has been shown in single-centre studies with historical controls to be associated with better oncological outcome. However, better evidence is needed. The main purpose of this PhD thesis was to investigate whether CME could be implemented in a colorectal surgical department in Denmark, whether more extensive dissection could demonstrate LN metastases outside the mesocolon, and to demonstrate a possible association between CME and improved oncological results without increased risk of perioperative mortality. This thesis includes five articles. Two articles (IV and V) are based on the population of patients undergoing elective resection for colon cancer in the Capital Region from June 2008 to December 2013. Two articles (II and III) are based on data from the local colon database in Hillerød, and the last article (I) is a systematic review concerning the risk of metastases from colon cancer to the central LNs in the mesocolon. Article I found a risk of metastases in central LNs to be reported in 1-22% of the cases of right-sided colon cancers, and in up to 12% of the cases with sigmoid tumours. The populations included and methods used in the studies were very heterogeneous and no definitive conclusions can be drawn. It was shown in article II that the surgical quality, i.e. quality of the specimens assessed by the pathologists, improved with implementation of CME in Hillerød. The vascular tie was higher, and the implementation was not associated with an increased risk of perioperative mortality. Article III demonstrated a risk of LN metastases in the gastrocolic ligament along the stomach for tumours located in the transverse colon, in the ascending or descending colon close to or in the flexures. It occurred in 4% of all patients and 13% of the patients with LN metastases in mesocolon. Resection of these LNs seems advisable for these tumour locations. Article IV showed no association between increased perioperative mortality and CME (n = 529) when compared with non-CME (n = 1,701). The 30-day mortality was 4.2% after CME compared with 3.7% after non-CME (p = 0.605), and the 90-day mortalities were 6.2% and 4.9% (p = 0.219) respectively. Odds ratios for 30-day and 90-day mortalities after CME were respectively 1.07 (95% confidence interval: 0.62-1.80) and 1.25 (0.77-1.94) in the multi-variable logistic regression analyses. Postoperative respiratory failure and need for vasopressors were significantly more frequent in the CME group and, besides CME itself, could be associated with the fewer laparoscopic resections and more severe preoperative comorbidity in the CME Group. Article V demonstrated an association between higher four-year disease-free survival for stage I-III tumours and CME (n = 364) when compared with non-CME (n = 1,031). Most notable was the difference for stage I and II cancers. The four-year disease-free survival for stage I was 100% in the CME group compared with 89.8% (83.1-96.6) in the non-CME group (p = 0.046). For stage II the disease-free survivals were 91.9% (87.2-96.6%) in the CME group and 77.9% (71.6-84.1%) in the non-CME group (p = 0.0033), and for stage III 73.5% (63.6-83.5) and 67.5% (61.8-73.2) (p = 0.13) respectively. In the multivariable Cox regression models, CME was a significant predictive factor for higher dis-ease-free four-year survival for stage I-III patients with hazard ratios (HR) for CME of 0.59 (0.42-0.83, p = 0.0025). For stage II the HR was 0.44 (0.23-0.86, p = 0.018) and for stage III 0.64 (0.42-1.00, p = 0.048).


Assuntos
Adenocarcinoma/cirurgia , Neoplasias do Colo/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Excisão de Linfonodo , Mesocolo/cirurgia , Colo/anatomia & histologia , Neoplasias do Colo/patologia , Intervalo Livre de Doença , Estudos de Viabilidade , Humanos , Metástase Linfática , Mesocolo/embriologia , Taxa de Sobrevida , Resultado do Tratamento
4.
Med Biol Eng Comput ; 55(3): 507-515, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27289590

RESUMO

The aim of this study was to evaluate feasibility and reproducibility of quantitative assessment of colonic morphology on CT colonography (CTC). CTC datasets from 60 patients with optimal colonic distension were assessed using prototype software. Metrics potentially associated with poor endoscopic performance were calculated for the total colon and each segment including: length, volume, tortuosity (number of high curvature points <90°), and compactness (volume of box containing centerline divided by centerline length). Sigmoid apex height relative to the lumbosacral junction was also measured. Datasets were quantified twice each, and intra-reader reliability was evaluated using concordance correlation coefficient and Bland-Altman plot. Complete quantitative datasets including the five proposed metrics were generated from 58 of 60 (97 %) CTC examinations. The sigmoid and transverse segments were the longest (55.9 and 51.4 cm), had the largest volumes (0.410 and 0.609 L), and were the most tortuous (3.39 and 2.75 high curvature points) and least compact (3347 and 3595 mm2), noting high inter-patient variability for all metrics. Mean height of the sigmoid apex was 6.7 cm, also with high inter-patient variability (SD 6.8 cm). Intra-reader reliability was high for total and segmental lengths and sigmoid apex height (CCC = 0.9991) with excellent repeatability coefficient (CR = 3.0-3.3). There was low percent variance of metrics dependent upon length (median 5 %). Detailed automated quantitative assessment of colonic morphology on routine CTC datasets is feasible and reproducible, requiring minimal reader interaction.


Assuntos
Colo/anatomia & histologia , Colonografia Tomográfica Computadorizada , Software , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
5.
Med Eng Phys ; 38(2): 148-54, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26762775

RESUMO

This paper presents a method of characterizing the distribution of colorectal morphometrics. It uses three-dimensional region growing and topological thinning algorithms to determine and visualize the luminal volume and centreline of the colon, respectively. Total and segmental lengths, diameters, volumes, and tortuosity angles were then quantified. The effects of body orientations on these parameters were also examined. Variations in total length were predominately due to differences in the transverse colon and sigmoid segments, and did not significantly differ between body orientations. The diameter of the proximal colon was significantly larger than the distal colon, with the largest value at the ascending and cecum segments. The volume of the transverse colon was significantly the largest, while those of the descending colon and rectum were the smallest. The prone position showed a higher frequency of high angles and consequently found to be more torturous than the supine position. This study yielded a method for complete segmental measurements of healthy colorectal anatomy and its tortuosity. The transverse and sigmoid colons were the major determinant in tortuosity and morphometrics between body orientations. Quantitative understanding of these parameters may potentially help to facilitate colonoscopy techniques, accuracy of polyp spatial distribution detection, and design of novel endoscopic devices.


Assuntos
Colo/anatomia & histologia , Colonoscopia/instrumentação , Robótica , Doenças Assintomáticas , Colo/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Decúbito Ventral , Reto , Decúbito Dorsal , Tomografia Computadorizada por Raios X
6.
Abdom Imaging ; 40(7): 2232-41, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26054979

RESUMO

PURPOSE: To develop a novel semi-automatic segmentation method for quantification of the colon from magnetic resonance imaging (MRI). METHODS: Fourteen abdominal T2-weighted and dual-echo Dixon-type water-only MRI scans were obtained from four healthy subjects. Regions of interest containing the colon were outlined manually on the T2-weighted images. Segmentation of the colon and feces was obtained using k-means clustering and image registration. Regional colonic and fecal volumes were obtained. Inter-observer agreement between two observers was assessed using the Dice similarity coefficient as measure of overlap. RESULTS: Colonic segmentations showed wide variation in volume and morphology between subjects. Colon volumes of the four healthy subjects for both observers were (median [interquartile range]) ascending colon 200 mL [169.5-260], transverse 200.5 mL [113.5-242.5], descending 148 mL [121.5-178.5], sigmoid-rectum 277 mL [192-345], and total 819 mL [687-898.5]. Overlap agreement for the total colon segmentation between the two observers was high with a Dice similarity coefficient of 0.91 [0.84-0.94]. The colon volume to feces volume ratio was on average 0.7. CONCLUSION: Regional colon volumes were comparable to previous findings using fully manual segmentation. The method showed good agreement between observers and may be used in future studies of gastrointestinal disorders to assess colon and fecal volume and colon morphology. Novel insight into morphology and quantitative assessment of the colon using this method may provide new biomarkers for constipation and abdominal pain compared to radiography which suffers from poor reliability.


Assuntos
Colo/anatomia & histologia , Imageamento por Ressonância Magnética , Adulto , Humanos , Aprendizado de Máquina , Masculino , Variações Dependentes do Observador , Valores de Referência , Reprodutibilidade dos Testes
7.
Artigo em Inglês | MEDLINE | ID: mdl-25571051

RESUMO

In this paper we investigate a method for segmentation of colorectal Narrow Band Imaging (NBI) endoscopic images with Support Vector Machine (SVM) and Markov Random Field (MRF). SVM classifiers recognize each square patch of an NBI image and output posterior probabilities that represent how likely the given patch falls into a certain label. To prevent the spatial inconsistency between adjacent patches and encourage segmented regions to have smoother shapes, MRF is introduced by using the posterior outputs of SVMs as a unary term of MRF energy function. Segmentation results of 1191 NBI images are evaluated in experiments in which SVMs were trained with 480 trimmed NBI images and the MRF energy was minimized by an α - ß swap Graph Cut.


Assuntos
Colo/anatomia & histologia , Endoscopia , Processamento de Imagem Assistida por Computador , Cadeias de Markov , Imagem de Banda Estreita/métodos , Reto/anatomia & histologia , Máquina de Vetores de Suporte , Humanos
8.
Proc Natl Acad Sci U S A ; 100(6): 3311-4, 2003 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-12610207

RESUMO

Most models of tumorigenesis assume that tumors are monoclonal in origin. This conclusion is based largely on studies using X chromosome-linked markers in females. One important factor, often ignored in such studies, is the distribution of X-inactivated cells in tissues. Because lyonization occurs early in development, many of the progeny of a single embryonic stem cell are grouped together in the adult, forming patches. As polyclonality can be demonstrated only at the borders of X-inactivation patches, the patch size is crucial in determining the chance of demonstrating polyclonality and hence the number of tumors that need to be examined to exclude polyclonality. Previously studies using X-linked genes such as glucose-6-phosphate dehydrogenase have been handicapped by the need to destroy the tissues to study the haplotypes of glucose-6-phosphate dehydrogenase [Fialkow, P.-J. (1976) Biochim. Biophys. Acta 458, 283-321] or to determine the restriction fragment length polymorphisms of X chromosome-linked genes [Vogelstein, B., Fearon, E. R., Hamilton, S. R. & Feinberg, A. P. (1985) Science 227, 642-645]. Here we visualize X-inactivation patches in human females directly. Results show that the patch size is relatively large in both the human colon and breast, confounding assessment of tumor clonality with traditional X-inactivation studies.


Assuntos
Mecanismo Genético de Compensação de Dose , Neoplasias/genética , Neoplasias/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/anatomia & histologia , Mama/enzimologia , Colo/anatomia & histologia , Colo/enzimologia , Feminino , Glucosefosfato Desidrogenase/genética , Heterozigoto , Humanos , Intestino Delgado/anatomia & histologia , Intestino Delgado/enzimologia , Pessoa de Meia-Idade , Mutação Puntual , Glândula Tireoide/anatomia & histologia , Glândula Tireoide/enzimologia
9.
J Am Pharm Assoc (Wash) ; 41(4): 585-95, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11486985

RESUMO

OBJECTIVE: To review prevention and management strategies for colorectal cancer, with an emphasis on studies pertaining to women. DATA SOURCES: Articles published from January 1990 through February 2001 identified through a MEDLINE search using the term colorectal cancer and the additional terms screening, prevention, and treatment. Additional references were identified from the bibliographies of the retrieved articles. DATA SYNTHESIS: Colorectal cancer is the third most common non-skin cancer in women, after breast and lung cancers. Many women underestimate their risk of colorectal cancer, which may lead them to underuse screening measures that have been proven to reduce disease morbidity and mortality. For average-risk women and men > or = 50 years of age, pharmacists should recommend regular screening for early detection and prevention of colorectal cancer. In its earliest, most curable stages, colorectal cancer is often asymptomatic. However, patients who report signs and symptoms, such as blood in the stool, abdominal pain, changes in bowel habits, unexplained weight loss, or iron deficiency anemia, should be referred for medical evaluation. The use of chemopreventive agents for colorectal cancer, such as nonsteroidal anti-inflammatory drugs, hormone replacement therapy, and dietary calcium, holds significant promise, but further studies are needed before these agents can be recommended for cancer prevention in the general population. Surgical resection is the primary treatment modality for colorectal cancer, and adjuvant chemotherapy is recommended in patients with stage III disease and some high-risk patients with stage II disease. Pharmacists should be aware that women are more susceptible to dose-related toxicity effects of fluorouracil and leucovorin combination chemotherapy, the first-line regimen for adjuvant chemotherapy. CONCLUSION: Although often perceived as a disease that primarily affects men, colorectal cancer is an equally important health concern for women. By providing education and counseling, pharmacists can help raise women's awareness of this disease and encourage them to take steps to significantly reduce their risk.


Assuntos
Neoplasias Colorretais , Saúde da Mulher , Quimioterapia Adjuvante , Colo/anatomia & histologia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/fisiopatologia , Neoplasias Colorretais/prevenção & controle , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Assistência Farmacêutica , Fatores de Risco , Estados Unidos/epidemiologia
10.
IEEE Trans Biomed Eng ; 43(2): 113-22, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8682522

RESUMO

Fluorescence spectroscopy of tissue is a promising technique for early detection of precancerous changes in the human body. Investigation of the microscopic origin of the clinically observed tissue fluorescence can provide valuable information about the tissue's histology. The objective of this study was the development of a morphological model of colon tissue fluorescence which connects the clinically observed spectra with their underlying microscopic origins. Clinical colon tissue fluorescence which connects the clinically observed spectra with their underlying microscopic origins. Clinical colon tissue fluorescence spectra were modeled by measuring the intrinsic fluorescence properties of colon tissue on a microscopic level and by simulating light propagation in tissue using the Monte-Carlo method. The computed spectra were in good agreement with the clinical spectra acquired during colonoscopy, and exhibited the characteristic spectral features of the in vivo collected spectra. Our analysis quantitated these spectral features in terms of the intrinsic fluorescence properties of tissue and its general histological characteristics. The fluorescence intensity difference between normal and adenoma observed in vivo was found to be due to the increased hemoglobin absorption, the reduced mucosal fluorescence intensity, and the absence of submucosal fluorescence in adenomatous polyps. The increased red fluorescence in adenoma was found to be associated with the dysplastic crypt cell fluorescence.


Assuntos
Colo/anatomia & histologia , Absorção , Adenocarcinoma/patologia , Adenoma/patologia , Pólipos Adenomatosos/patologia , Colo/patologia , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/patologia , Pólipos do Colo/patologia , Colonoscopia , Simulação por Computador , Fluorescência , Hemoglobinas/efeitos da radiação , Humanos , Mucosa Intestinal/patologia , Luz , Microscopia , Microespectrofotometria , Método de Monte Carlo , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/patologia , Espalhamento de Radiação , Espectrometria de Fluorescência
11.
Lasers Surg Med ; 15(4): 351-7, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7885168

RESUMO

Using a spectrophotometer equipped with an internal integrating sphere, the absorption (mu a) and the reduced scattering (microseconds') coefficients of ex vivo human colon tissues were evaluated from reflectance and transmittance measurements. Mu a and microseconds' varied from 47.7 to 1.0 cm-1 and from 14.2 to 6.2 cm-1, respectively, on passing from 300 nm to 800 nm. These results can be used to estimate the optical penetration depths when photodynamic therapy or light-induced fluorescence procedures are used.


Assuntos
Colo/anatomia & histologia , Espectrofotometria , Absorção , Colágeno/efeitos da radiação , Colo/efeitos da radiação , Tecido Conjuntivo/anatomia & histologia , Tecido Conjuntivo/efeitos da radiação , Fluorescência , Humanos , Mucosa Intestinal/anatomia & histologia , Mucosa Intestinal/efeitos da radiação , Linfócitos/citologia , Linfócitos/efeitos da radiação , Método de Monte Carlo , Músculo Liso/anatomia & histologia , Músculo Liso/efeitos da radiação , Óptica e Fotônica , Fotoquimioterapia , Plasmócitos/citologia , Plasmócitos/efeitos da radiação , Espalhamento de Radiação , Espectrofotometria Ultravioleta
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