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A novel model of distal colon cancer in athymic mice
Priolli, Denise Gon?alves;Abrantes, Ana Margarida;Neves, Silvia;Batista, Joana Neves;Cardinalli, Izilda Aparecida;Botelho, Maria Filomena;
Acta Cirurgica Brasileira , 2012, DOI: 10.1590/S0102-86502012000600001
Abstract: purpose: the present a novel adenocarcinoma model in athymic mice. methods: seven athymic mice were used. colon diversion and distal fistula were made. adenocarcinoma cells were inoculated in the submucosa of fistula. tumor growth was monitored daily. scintigraphy with 99mtc-mibi was performed to identify the tumor. results: the model of distal colon cancer is feasible. tumor detection was possible by both, macroscopically and molecular imaging. all resections demonstrated poorly differentiated tumors. colon obstruction occurred in one case, similarly to evolution in human tumors of distal colon. conclusion: the proposed model of distal colon cancer is feasible, allows for easy monitoring of tumoral growth by both, macroscopically and molecular imaging, and is suitable for studying the evolution of tumor with implementation of cytotoxic therapy in vivo.
Mirjana Radenkovic,Slavimir Veljkovi?,Ranka Samrdzic,Milan ?iri?
Acta Medica Medianae , 2000,
Abstract: The influence of the non-selective blocker of the muscarinic receptors, namely of the atropine (1,7 x10-10 - 5x10-7). upon thependulousmovements of the proximal and of the distal colon of the rabbit was studied. In the correct proportion to the concentration the atropine reduces the amplitude of both the proximal (r=0,98; P<0,001) and of the distal colon (r= 0,97; P < 0,001). On the basis of the ED50 values - that amount to 7,7 ± 0,03 x 10-7 M for the proximal colon and 3,5 ± 0,06 x 10-5 M for the distal colon, the atropine recluces for twenty times the amplitude of the pendulousmovements of the rabbit's distal colon. Likewise, it reduces for dozen times the frequency of the pendulous movements of the distal colon (ED50 = 5 ± 0,02 x 10-6M) with respect to the proximal one (ED50 = 4,7 ± 0,06 x I0-5M). The atropine does not change the tone of the proximal colon (average relaxation is 5,47 ± 2,32 %) while it induces the concentrically-dependent relaxation of the distal colon (maximal relaxation amounts to 38.03 + 8,34). The ED50 values for the atropine while affecting the distal colon tone is 1,7 ± 0,03 x 10-6M.
Translocation of an Intrauterine Contraceptive Device: Incidental Finding in the Rectosigmoid Colon  [PDF]
R. Vilallonga,N. Rodriguez,M. Vilchez,M. Armengol
Obstetrics and Gynecology International , 2010, DOI: 10.1155/2010/404160
Abstract: The presence of an intrauterine device (IUD) within the colon is rare. Complications have been reported with IUDs among which uterine perforation. Translocation of IUDs to the uterine cavity, to the bladder and also through the wall of the bowel, and sigmoid colon has been reported. We believe there may be a case that surgeons should know the result of despite being a priori gynaecological complication. This paper reports on a case of colon perforation by an IUD. The IUD is a commonly used reversible birth control method. One of the rare, but potentially serious complication is uterine perforation. In this paper, we report the exceptional case of an asymptomatic IUD translocation to the rectosigmoid colon lumen secondary to uterine perforation. A 31-year-old patient was admitted to the emergency department complaining of proctalgia for one month. Unfortunately, no information was available regarding the IUD insertion procedure. The patient had a delivery fifteen months before. A rectal exploration showed the presence of a foreign body. An X-Ray showed a IUD. CT scan was performed and showed a normal uterus and a metallic piece entering the rectum. This CT scan incidentally revealed the presence of an IUD in the lumen of the rectosigmoid colon (See Figure 1). Removal of the device by means of endoscopic procedure was not performed. The patient underwent a surgical exploration and the IUD was removed from the rectum transanally. The postoperative course was uneventful. Figure 1: IUD is displayed in the rectum (arrow) after perforating the uterus located in front. Uterine perforation is a rarely observed complication. The incidence of IUD perforation ranges from 0.05/1,000 to 13/1,000 [1, 2]. Many authors have recommended that IUDs should be inserted by skilled providers to prevent complications such as uterine perforation [3]. IUD migration is more frequent in women who undergo labour with their IUD in place. In this last situation, due to the reduction in the size of the uterus and thinning of the uterine walls in the postpartum as a result of hypoestrogenemia, the uterus becomes more susceptible to perforation [2]. May be this could have contributed to the perforation in the case presented here. May be this could have been another explanation in our case. Colon perforation is rare but has been described previously [4]. Another location of migration is the bladder because of its close proximity to the uterus [5] or the peritoneal cavity [6]. Other cases have been described as mimicking chronic appendicitis [7]. X-Ray and TVS can be helpful but CT scan
Eosinophilic Gastroenteritis Involving the Distal Small Intestine and Proximal Colon  [PDF]
Guan-Yeow Ong,Chia-Chang Hsu,Chi-Sin Changchien,Sheng-Nan Lu
Chang Gung Medical Journal , 2002,
Abstract: Eosinophilic gastroenteritis (EG) is an unusual disorder. It is characterized byeosinophil infiltration of the gut wall histologically and is manifested by gastrointestinal(GI) symptoms clinically. This disease entity preferentially affects the stomach and proximalsmall intestine. Mucosal layer disease is the most common form of this uncommon disease.We present a case of EG with transmural distal small intestinal and proximal colonicinvolvement whose clinical symptoms included watery diarrhea, abdominal pain, and bodyweight loss. Colonoscopy showed non-specific colitis in the proximal colon. Small bowelseries showed diffuse jejunal dilatation with wall thickening and rigidity. Abdominal computedtomography also showed a thickened bowel wall with partial ileus and ascites.Diagnosis was established through endoscopic biopsy and ascites paracentesis, while at thesame time excluding the possibility of parasite infection. Treatment with prednisolone produceda dramatic response. A high index of suspicion in cases of peripheral eosinophiliawith concomitant GI symptoms is needed for the early diagnosis of this uncommon disease.
Metabolic syndrome, lifestyle risk factors, and distal colon adenoma: A retrospective cohort study  [cached]
Moon-Chan Kim,Chang-Sup Kim,Tae-Heum Chung,Hyoung-Ouk Park
World Journal of Gastroenterology , 2011, DOI: 10.3748/wjg.v17.i35.4031
Abstract: AIM: To investigate relationships between colorectal adenoma incidence, metabolic syndrome (MS) components and lifestyle factors. METHODS: We conducted a retrospective cohort study using data from individuals who had multiple sigmoidoscopies for colon cancer at the Health Promotion Center of Ulsan University Hospital in Korea from 1998 to 2007. RESULTS: By multivariate analysis, the incidence of distal colon adenoma was increased by more than 1.76 times in individuals with at least one component of MS compared to those without a component of MS. After adjustment for age, gender, smoking, drinking, and physical exercise, only high body mass index (BMI) was significantly associated with the incidence of distal colon adenoma (Hazard ratio 1.66, 95% confidence interval 1.05-2.62). CONCLUSION: Our results suggest that high BMI may increase the risk of colorectal adenoma in Korean adults.
Nonfunctioning Juxtaglomerular Cell Tumor  [PDF]
Ryoko Sakata,Hiroaki Shimoyamada,Masahiro Yanagisawa,Takayuki Murakami,Kazuhide Makiyama,Noboru Nakaigawa,Yoshiaki Inayama,Kenichi Ohashi,Yoji Nagashima,Masahiro Yao,Yoshinobu Kubota
Case Reports in Pathology , 2013, DOI: 10.1155/2013/973865
Abstract: The juxtaglomerular cell tumor (JGCT) is a rare renal tumor characterized by excessive renin secretion causing intractable hypertension and hypokalemia. However, asymptomatic nonfunctioning JGCT is extremely rare. Here, we report a case of nonfunctioning JGCT in a 31-year-old woman. The patient presented with a left renal tumor without hypertension or hypokalemia. Under a clinical diagnosis of renal cell carcinoma, radical nephrectomy was performed. The tumor was located in the middle portion adjacent to the renal pelvis, measuring 2?cm in size. Pathologically, the tumor was composed of cuboidal cells forming a solid arrangement, immunohistochemically positive for renin. Based on these findings, the tumor was diagnosed as JGCT. In cases with hyperreninism, preoperative diagnosis of JGCT is straightforward but difficult in nonfunctioning case. Generally, JGCT presents a benign biological behavior. Therefore, we should take nonfunctioning JGCT into the differential diagnoses for renal tumors, especially in younger patients to avoid excessive surgery. 1. Introduction Juxtaglomerular cell tumor (JGCT), a neoplasm derived from the juxtaglomerular cell of the kidney, was first described by Robertoson et al. and Kihara et al. [1, 2]. Since then, approximately 100 cases have been reported in the literature. Clinically, this tumor is characterized by hypertension due to excessive renin secretion by tumor cells causing secondary hyperaldosteronism [1–3]. Generally, its preoperative diagnosis is relatively easy, because of typical presence of hypertension concomitant with hypokalemia. However, it is quite difficult in cases of asymptomatic nonfunctioning JGCT [3]. Here, we present a case of nonfunctioning JGCT, which is the fourth case reported so far to the best of our knowledge [4–6]. 2. Case Report A 31-year-old woman was referred to our hospital with a left renal tumor incidentally detected during examination for left-side abdominal pain. She had no history of hypertension, and her blood pressure at presentation was 116/62?mmHg. All the laboratory data, including electrolyte levels, were within normal ranges. Unfortunately, preoperative plasma renin activity was not assayed. Unenhanced computed tomography (CT) revealed solitary well-circumscribed mass lesion measuring 2?cm with fine calcifications in the middle portion adjacent to the renal pelvis of the left kidney. Dynamic-enhanced CT demonstrated that the tumor was not enhanced in the corticomedullary (early) phase but enhanced in the excretory (late) phase (Figure 1). Magnetic resonance image (MRI) showed
Sources of calcium in agonist-induced contraction of rat distal colon smooth muscle in vitro
Hua Zhou, De-Hu Kong, Qun-Wan Pan, Hai-Hua Wang
World Journal of Gastroenterology , 2008,
Abstract: AIM: To study the origin of calcium necessary for agonist-induced contraction of the distal colon in rats.METHODS: The change in intracellular calcium concentration ([Ca2+]i) evoked by elevating external Ca2+ was detected by fura 2/AM fluorescence. Contractile activity was measured with a force displacement transducer. Tension was continuously monitored and recorded using a Powerlab 4/25T data acquisition system with an ML110 bridge bioelectric physiographic amplifier.RESULTS: Store depletion induced Ca2+ influx had an effect on [Ca2+]i. In nominally Ca2+-free medium, the sarco-endoplasmic reticulum Ca2+-ATPase inhibitor thapsigargin (1 μmol/L) increased [Ca2+]i from 68 to 241 nmol/L, and to 458 (P < 0.01) and 1006 nmol/L (P < 0.01), respectively, when 1.5 mmol/L and 3.0 mmol/L extracellular Ca2+ was reintroduced. Furthermore, the change in [Ca2+]i was observed with verapamil (5 μmol/L), La3+ (1 mmol/L) or KCl (40 mmol/L) in the bathing solution. These channels were sensitive to La3+ (P < 0.01), insensitive to verapamil, and voltage independent. In isolated distal colons we found that in normal Krebs solution, contraction induced by acetylcholine (ACh) was partially inhibited by verapamil, and the inhibitory rate was 41% (P < 0.05). On the other hand, in Ca2+-free Krebs solution, ACh induced transient contraction due to Ca2+ release from the intracellular stores. The transient contraction lasted until the Ca2+ store was depleted. Restoration of extracellular Ca2+ in the presence of atropine produced contraction, mainly due to Ca2+ influx. Such contraction was not inhibited by verapamil, but was decreased by La3+ (50 μmol/L) from 0.96 to 0.72 g (P < 0.01).CONCLUSION: The predominant source of activator Ca2+ for the contractile response to agonist is extracellular Ca2+, and intracellular Ca2+ has little role to play in mediating excitation-contraction coupling by agonists in rat distal colon smooth muscle in vitro. The influx of extracellular Ca2+ is mainly mediated through voltage-, receptor- and store-operated Ca2+ channels, which can be used as an alternative to develop new drugs targeted on the dysfunction of digestive tract motility.
Telmisartan Inhibits Cell Proliferation by Blocking Nuclear Translocation of ProHB-EGF C-Terminal Fragment in Colon Cancer Cells  [PDF]
Keiji Ozeki, Satoshi Tanida, Chie Morimoto, Yoshimasa Inoue, Tsutomu Mizoshita, Hironobu Tsukamoto, Takaya Shimura, Hiromi Kataoka, Takeshi Kamiya, Eiji Nishiwaki, Hiroshi Ishiguro, Shigeki Higashiyama, Takashi Joh
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0056770
Abstract: Background & Aims Current treatment target toward advanced colorectal cancers is mainly focused on the epidermal growth factor receptor (EGFR) signaling, but its additive effects with chemotherapy are still limited. A disintegrin and metalloproteinase (ADAM) cleaves the proheparin-binding epidermal growth factor like growth factor (proHB-EGF). And soluble HB-EGF activates EGFR. In parallel, the carboxy-terminal fragment of proHB-EGF (HB-EGF-CTF) translocates into the inner nuclear membrane, and subsequently exerts on the regulation of cell proliferation by binding nuclear promyelocytic leukemia zinc finger (PLZF) protein, a transcriptional repressor, thereby causing its nuclear export. We hypothesized that the inhibition of HB-EGF-CTF nuclear translocation may be a new strategy in preventing cell proliferation. Methods 12-O-tetradecanoylphorbor-13-acetate (TPA) was treated to activate ADAM. Nine-thousand chemical compounds were screened for their efficacies in blocking the binding of HB-EGF-CTF to promyelocytic leukemia zinc finger (PLZF) with Alphascreen system. The obtained candidates were then used to block the binding of HB-EGF-CTF to PLZF in colon cancer cells, HT29 and HCT116. Cell proliferation was investigated with a growth curve assay. The intracellular localization, and association between HB-EGF-CTF and PLZF, was assessed with immunofluorescent staining, and immunoprecipitation and Western blotting, respectively. The effects of obtained candidates on EGFR phosphorylation and on nuclear translocation of HB-EGF-CTF and export of PLZF during the angiotensin II type1 receptor (AT1R) knockdown were also investigated. Results Telmisartan and candesartan were found to be potential candidates. Telmisartan inhibited TPA-induced cell proliferation stronger than candesartan. Telmisartan, but not candesartan blocked the nuclear translocation of HB-EGF-CTF, and binding of HB-EGF-CTF to PLZF, during TPA stimulation. Both telmisartan and candesartan did not inhibit TPA-induced EGFR phosphorylation, and telmisartan, but not candesartan, inhibited TPA-induced nuclear translocation of HB-EGF-CTF after knockdown of AT1R. Conclusions The inhibition of HB-EGF-CTF nuclear translocation with telmisartan may be a novel strategy in preventing cell proliferation.
Pictorial essay: Distal colostography  [cached]
Rahalkar Mukund,Rahalkar Anand,Phadke Dilip
Indian Journal of Radiology and Imaging , 2010,
Abstract: Distal colostography (DC), also called distal colography or loopography, is an important step in the reparative management of anorectal malformations (ARMs) with imperforate anus, Hirschsprung′s disease (occasionally) and colonic atresia (rarely) in children and obstructive disorders of the distal colon (colitis with stricture, carcinoma or complicated diverticulosis) in adults. It serves to identify/confirm the type of ARM, presence/absence of fistulae, leakage from anastomoses, or patency of the distal colon. We present a pictorial essay of DC in a variety of cases.
Proliferative enteropathy (PE): Induced changes in galanin-like immunoreactivity in the enteric nervous system of the porcine distal colon
Gonkowski S.,Burlinski P.,Calka J.
Acta Veterinaria , 2009, DOI: 10.2298/avb0904321g
Abstract: The aim of this study was to investigate the changes of galanin (GAL) like immonoreactivity in the porcine descending colon during proliferative entheropathy (PE). Accordingly, the distribution pattern of GAL - like immunoreactive (GAL-LI) nerve structures was studied by the immunofluorescence technique in the circular muscle layer, myenteric (MP), outer submucous (OSP) and inner submucous plexuses (ISP), as well as in the mucosal layer of the porcine descending colon under physiological conditions and during PE. In control animals GAL-LI perikarya have been shown to constitute 4.03 ± 0.1%, 6.67 ± 0.3% and 11.20 ± 0.5% in MP, OSP and ISP, respectively. PE caused changes in the GAL - like immunoreactivity, which differed in particular parts of the studied bowel segment. During PE the number of GAL-LI perikarya amounted to 2.90±0.5%, 8.42±1.0% and 21.72±1,4% within the MP, OSP and ISP, respectively. Moreover PE caused an increase in the number of GAL-LI nerve fibers in the colonic circular muscle and mucosal layers, as well as in all intramural plexuses, especially in ISP, where nearly every ganglion contained a very dense meshwork of the GAL-positive nerve fibers under the studied pathological factor. This study for the first time reports on changes in GAL-LI nerve structures of the porcine descending colon during Lawsonia intracellularis infection.
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