Increased endothelin receptor B and G protein coupled kinase-2 in the mesentery of portal hypertensive rats

AIM: To elucidate the mechanisms of mesenteric vasodilation in portal hypertension (PHT), with a focus on endothelin signaling. METHODS: PHT was induced in rats by common bile duct ligation (CBDL). Portal pressure (PP) was measured directly via catheters placed in the portal vein tract. The level of endothelin-1 (ET-1) in the mesenteric circulation was determined by radioimmunoassay, and the expression of the endothelin A receptor (ETAR) and endothelin B receptor (ETBR) was assessed by immunofluorescence and Western blot. Additionally, expression of G protein coupled kinase-2 (GRK2) and β-arrestin 2, which influence endothelin receptor sensitivity, were also studied by Western blot. RESULTS: PP of CBDL rats increased significantly (11.89 ± 1.38 mmHg vs 16.34 ± 1.63 mmHg). ET-1 expression decreased in the mesenteric circulation 2 and 4 wk after CBDL. ET-1 levels in the systemic circulation of CBDL rats were increased at 2 wk and decreased at 4 wk. There was no change in ETAR expression in response to CBDL; however, increased expression of ETBR in the endothelial cells of mesenteric arterioles and capillaries was observed. In sham-operated rats, ETBR was mainly expressed in the CD31+ endothelial cells of the arterioles. With development of PHT, in addition to the endothelial cells, ETBR expression was noticeably detectable in the SMA+ smooth muscle cells of arterioles and in the CD31+ capillaries. Following CBDL, increased expression of GRK2 was also found in mesenteric tissue, though there was no change in the level of β-arrestin 2. CONCLUSION: Decreased levels of ET-1 and increased ETBR expression in the mesenteric circulation following CBDL in rats may underlie mesenteric vasodilation in individuals with PHT. Mechanistically, increased GRK2 expression may lead to desensitization of ETAR, as well as other vasoconstrictors, promoting this vasodilatory effect.

Huge peripheral primitive neuroectodermal tumor of the small bowel mesentery at nonage:A case report and review of the literature

Extraskeletal Ewing's sarcoma/peripheral primitive neuroectodermal tumor(E-EWS/pP NET) is a rare aggressive malignant small round cell tumor. In this report, we present the case of a 15-year-old boy who suffered from acute abdominal pain accompanied by hematemesis and melena, and was eventually diagnosed with E-EWS/p PNET. To date, there have been only five reported cases of E-EWS/pP NET of the small bowel including the patient in this report. To the best of our knowledge, this is the first documentation of a pP NET of the small bowel mesentery at nonage. All these have made this report rare and significant.

Dedifferentiated liposarcoma of the small bowel mesentery presenting as a submucosal mass

Dedifferentiated liposarcoma(DDLPS) is a variant of liposarcoma but with a more aggressive course.It occurs most commonly in the retroperitoneum and rarely in any other anatomical location.We describe a case of DDLPS arising from the small bowel mesentery presenting as submucosal mass of the small bowel.The current case is unusual as the tumor originated from the small bowel mesentery and a dedifferentiated component transmurally invaded the small bowel wall,including the small bowel submucosa.

Glytan decreases portal pressure via mesentery vasoconstriction in portal hypertensive rats

AIM: To investigate the effects of Glytan on splanchnic hemodynamics and its reduction of portal pressure in portal hypertensive rats.METHODS:Glytan(Ganluotong in Chinese),is composed of salvianolic acid B and diammonium glycyrrhizinate.Portal hypertension(PHT)was induced in the rats by common bile duct ligation(BDL).Hemodynamic studies were performed using the colored microsphere method.Radioimmunoassay(RIA)was used to determine endothelin(ET)-1 levels in the mesenteric circulation.Western blotting methods were used to investigate the effect of Glytan on ET A receptor(ETAR),ET B receptor(ETBR),endothelial NO synthase(e NOS),G-protein-coupled receptor kinase(GRK)2,and β-arrestin 2 expression in the mesentery.The m RNA of ETAR and ETBR was determined using real-time polymerase chain reaction.RESULTS:Treatment with Glytan reduced portal pressure(PP)and portal territory blood flow(PTBF)and increased both mean arterial pressure(MAP)and splanchnic vascular resistance(SVR).Especially at 4wk,PP decreased by about 40%,while MAP increased by 13%,SVR increased by 12%,and PTBF decreased by about 21%.The effect of blood flow reduction was greatest in the mesentery(about 33%)at 4 wk.The mesenteric circulation ET-1 levels of BDL rats were lower and negatively correlated with PP at 4 wk.Glytan can increase mesenteric ET-1 content and inhibit ETBR,e NOS,GRK2,andβ-arrestin 2 expression in the mesentery.Moreover,Glytan showed no effect on the expression of ETAR protein and m RNA.CONCLUSION:The decreased PP and PTBF observed after Glytan treatment were related to increased mesenteric vasoconstriction and increased receptor sensitivity to vasoconstrictor.

Studies on the flow and distribution of leukocytes in mesentery microcirculation of rats

AIM To study the effect of leukocyteendothelium interaction (LEI) on the flow anddistribution of leukocytes in microcirculationunder physiological condition.METHODS A microcirculation image multipleparameter computer analysis system (MIMPCAS)was used to study the flow and distribution ofleukocytes in mesentery microcirculation of ratsIn vivo.RESULTS The difference of visible leukocyteflux (VLF) was as high as 131 times in thearterioles and venules with similar diameter andblood velocity. The visible leukocytes rolledalong the blood vessel wall as a" jerky"movement. The frequency distribution of thevisible leukocyte velocity (VLV) showed a "twopeak" Curve. The low peak value was at 10 pm/ s-- 15 pm/ s while the high peak fell between25 pm/ s-- 30 pm/ s. With the increase of diameterof venules, VLF increased while the VLVremained at the same level. With the increase ofRBC velocity, VLV trends to elevate and VLF tofal I down.CONCLUSION The results herein might providea basic theory for the study on the mechanism ofLEI under physiological condition and novelmethods for the prevention and treatment of highLEI in many pathological

Metastatic low-grade endometrial stromal sarcoma with variable morphologies in the ovaries and mesentery: A case report

BACKGROUND Low-grade endometrial stromal sarcoma(LGESS)classically exhibits a proliferative morphology.However,morphological variation of extrauterine tumors presents a diagnostic challenge.CASE SUMMARY We report the case of a 76-year-old female patient with extensive extrauterine and abdominal neoplastic lesions.Computed tomography showed massive pleural and ascitic fluid,and there was an increase in serum cancer antigen 125.She underwent bilateral adnexectomy and tumor resection.The right ovary had been replaced by a multinodular mass that was 8.5 cm×4.5 cm×3.5 cm in size.In addition,there was a 24 cm×15 cm×13 cm mesenteric mass,which was also multinodular,with local invasion of the intestinal serosa and underlying muscle.Under the microscope,the tumors in different places exhibited two different patterns,thus presenting great challenges to diagnosis and treatment.Thorough pathological assessment eliminated all differential diagnoses in favor of metastatic LGESS derived from a 20-year-old primary tumor initially misdiagnosed as leiomyosarcoma.CONCLUSION LGESS morphology varies according to tumor location.Accurate diagnosis is critical for appropriate treatment and improved prognosis and patient care.

TFE3-expressing malignant perivascular epithelioid cell tumor of the mesentery:A case report and review of literature

BACKGROUND Perivascular epithelioid cell tumor(PEComa)is a rare mesenchymal tumor that exhibits an epithelioid and spindle cell morphology.The tumor is characterized by immunoreactivity for melanocytic and myogenic markers but can be misdiagnosed as more common tumors with similar characteristics,including gastrointestinal stroma tumors or leiomyosarcomas.Recently,a subset of PEComas has been reported to harbor a transcription factor binding to TFE3 fusion.Herein,we report a rare case of TFE3-expressing malignant PEComa arising from the mesentery.CASE SUMMARY A 50-year-old woman presented with abdominal discomfort for 3 months.Results of laboratory tests were all within the normal ranges,and the patient had no notable medical history.Magnetic resonance imaging revealed a large tumor on the right side of the pelvic floor,which was originally suspected to be a primary ovarian tumor.However,during surgery,the tumor was revealed to have originated from the mesentery.Histologically,the tumor was composed of bundles of spindle cells and sheets of epithelioid cells.Extensive coagulative necrosis and numerous mitotic figures were observed.Immunohistochemistry revealed that the tumor cells were positive for smooth muscle actin,HMB-45,and TFE3 expression.Tumor involvement of the rectal serosa was identified,leading to a final diagnosis of malignant PEComa of the mesentery.Surgical resection was followed by adjuvant chemotherapy.No recurrence or metastasis was observed over a 6-month follow-up period.CONCLUSION Malignant PEComa of the mesentery is extremely rare and should be distinguished from morphological mimics through differential diagnosis and immunohistochemistry.

Extensive abdominal lymphangiomatosis involving the small bowel mesentery: A case report

BACKGROUND Abdominal lymphangiomatosis is a rare benign condition accounting for less than 1%of all the cases of lymphangiomatosis.Management usually involves radical surgical excision;however,depending upon the extent of involvement,patient condition,and absence of complications,conservative management can be also considered.CASE SUMMARY We present the case of a 32-year-old male who presented with short onset abdominal pain and melena.Physical examination findings were within normal limits,except for left lower abdominal tenderness.Upper gastrointestinal endoscopy was within normal limits.Abdominal and pelvic ultrasound and computed tomography(CT)scan revealed numerous,variably-sized cystic lesions within the abdominal cavity,exclusively and extensively affecting the small bowel mesentery with sparing of the retroperitoneum.The diagnosis was confirmed by CT and cytological examination.Radical surgical excision was technically impossible in this patient because of the extensive involvement of the mesentery;therefore,the patient was managed conservatively.CONCLUSION Extensive and exclusive small bowel mesentery involvement in abdominal lymphangiomatosis is rare.Imaging modalities play an important role in establishing the diagnosis and conservative management can be considered when surgery is technically impossible.

Mesentery solitary fibrous tumor with postoperative recurrence and sarcomatosis: A case report and review of literature

BACKGROUND Solitary fibrous tumors are rare neoplasms of mesenchymal origin. They are often of low malignant potential and rarely metastasize. They frequently arise from the pleura and can occur at any soft tissue site in the body. However, these tumors rarely develop in the mesentery, peritoneal cavity or peritoneum.CASE SUMMARY We report on a scarce case of solitary fibrous tumor of the rectal mesentery showing sarcomatosis about 4 years after previous tumor resection. This 69-yearold male had no clinical symptoms but was transferred to our hospital because of a suspected tumor recurrence from follow-up abdominal computed tomography.Tumor markers(CEA, CA 19-9 and CA 125) were within the normal range. Open laparotomy showed sarcomatosis, and pathology confirmed its mesenchymal origin and diagnosis as the solitary fibrous tumor. Our case may be the second recurrent mesentery solitary fibrous tumor reported to date, and the only one with progression to sarcomatosis. There has been no evidence of recurrence in follow-up at the 28 th mo after extensive intra-operative peritoneal lavage and cytoreductive surgery.CONCLUSION Although there are few risk factors of cancer recurrence in this patient, careful long-term followup after cytoreductive surgery is necessary.

THE DIAGNOSIS OF MESENTERY TUMOR (CLINIC-PATHOLAGIC ANALYSIS OF 171 CASES)

One hundred and seventy one patients with mesentery tumors confirmed by surgery and/or pathology in five hospitals of Hubei Province from 1966 to 1986 are analyzed retrospectively. The main manifestations were abdominal pain, abdominal mass and emaciation. Cyst and leiomyomas were common in benign tumors. Malignant lymphoma, leiomyosarcoma and liposarcoma were predominant in malignant tumors. The morbidity, clinicopatholo-gic characteristics, diagnosis and differential diagnosis of this group of tumor are discussed.

Small bowel autotransplantation combined with pancreato-duodenectomy for enormous cavernous hemangioma of the small intestine mesentery

Recent advances in transplantation techniques have allowed pancreatoduodenectomy, distal gastrectomy,hemicolectomy and small bowel autotransplantation to be the therapy of choice for enormous cavernous hemangioma of the small intestine mesentery. There have been a few case reports about small bowel autotransplantation combined with pancreatoduodenectomy for enormous mesenteric cavernous hemangioma of small intestine. The present surgical methods for enormous cavernous bemangioma of the small intestine mesentery mainly included tumor excision and/or small bowel resection. However, these therapies are not effective for those patients in whom the angiocavemoma has infiltrated the mesenteric artery or pancreas, and these patients often give up therapy. It is recognized that enormous cavernous hemangioma of the small intestine mesentery is a benign lesion, and patients may have an excellent prognosis after complete resection of the lesion.

Spontaneous hematoma in the root of the small bowel mesentery:imaging findings

Retroperitoneal or mesenteric hemorrhage is mainlycaused by clinical trauma. Spontaneous retroperitoneal ormesenteric hemorrhage is rarely seen in the root of thesmall bowel mesentery. In this report, we describe

Clinical significance of mesenteric panniculitis-like abnormalities on abdominal computerized tomography in patients with malignant neoplasms

AIM To clarify the association of malignancy with mesenteric panniculitis-like changes on computed tomography(CT).METHODS All abdominal CT scans performed at North Shore University HealthS ystem showing mesenteric panniculitis from January 2005 to August 2010 were identified in the Radnet(Rad Net Corporation, Los Angeles, CA) database. Patients with a new or known diagnosis of a malignancy were included for this analysis. Longitudinal clinical histories were obtained from electronic medical records.RESULTS In total, 147794 abdominal CT scans were performed during the study period. Three hundred and fiftynine patients had mesenteric panniculitis(MP)-like abnormalities on their abdominal CT. Of these patients, 81 patients(22.6%) had a known history of cancer at the time of their CT scan. Nineteen(5.3%) had a new diagnosis of cancer in concurrence with their CT, but the majority of these(14/19, 74%) were undergoing CT as part of a malignancy evaluation. Lymphomas were the most common cancers associated with MPlike findings on CT(36 cases, 36%), with follicular lymphoma being the most frequent subtype(17/36). A variety of solid tumors, most commonly prostate(7) and renal cell cancers(6) also were seen. CT follow up was obtained in 56 patients. Findings in the mesentery were unchanged in 45(80%), worsened in 6(11%), and improved in 5 patients(9%). Positron emission tomography(PET) scans performed in 44 patients only showed a positive uptake in the mesenteric mass in 2 patients(5%). CONCLUSION A new diagnosis of cancer is uncommon in patients with CT findings suggestive of MP. MP-like mesenteric abnormalities on CT generally remain stable in patients with associated malignancies. PET scanning is not recommended in the evaluation of patients with mesenteric panniculitis-like findings on CT.

Rare case of an abdominal mass: Reactive nodular fibrous pseudotumor of the stomach encroaching on multiple abdominal organs

Reactive nodular fibrous pseudotumor(RNFP), which presents abdominal clinical manifestations and malignant radiographic results, usually requires radical resection as the treatment. However, RNFP has been recently described as an extremely rare benign postinflammatory lesion of a reactive nature, which typically arises from the sub-serosal layer of the digestive tract or within the surrounding mesentery in association with local injury or inflammation. In addition, a postoperative diagnosis is necessary to differentiate it from the other reactive processes of the abdomen. Furthermore, RNFP shows a good prognosis without signs of recurrence or metastasis. A 16-year-old girl presented with a 3-mo history of epigastric discomfort, and auxiliary examinations suggested a malignant tumor originating from the stomach; postoperative pathology confirmed RNFP, and after a 2-year follow-up period, the patient did not display any signs of recurrence. This case highlights the importance of preoperative pathology for surgeons who may encounter similar cases.

Superior mesenteric venous thrombosis after laparoscopic radical resection of rectal cancer: a report of a rare case and literature review

Mesenteric venous thrombosis(MVT) is rare, but life-threatening. MVT is often characterized by occult and nonspecific signs and symptoms. Diagnosis requires a high index of clinical suspicion, and emergency surgery is necessary to optimize patient survival, especially in people aged more than 70 years. MVT is a rare but fatal complication after laparoscopic radical surgery for rectal cancer. This study reports a case of extensive intestinal ischemic infarction caused by acute MVT after laparoscopic radical surgery for rectal cancer in a 70-year-old male.

Giant cystic lymphangioma originating from the lesser curvature of the stomach

Cystic lymphangiomas are rare benign tumors.Most frequently occurring in children and involving the neck or axilla,these tumors are much less common in adults and very rarely involve the abdomen.The known congenital and acquired(traumatic)etiologies result in failure of the lymphatic channels and consequent proliferation of lymphatic spaces.This case report describes a very rare case of a giant mesenteric cystic lymphangioma in an adult male with no clear etiology and successful resolution by standard radical resection.A previously healthy 44-year-old male presented with a 6-wk history of progressive upper abdominal pain,vomiting,anorexia and unintentional weight loss accompanied by rapid abdominal distension.A palpable mass was detected upon physical examination of the distended abdomen and abdominal computed tomography scan showed a giant multilobulated cystic process,measuring 40 cm in diameter.Exploratory laparotomy revealed an enormous cystic mass containing 6 L of serous fluid.The process appeared to originate from the lesser omentum and the lesser curvature of the stomach.Radical resection of the tumor was performed along with a partial gastrectomy to address potential invasion into the adjacent tissues.Histological analysis confirmed the diagnosis of a multicystic lymphangioma.The postoperative recovery was uneventful and the patient was discharged after 6 d.At 3-mo follow-up,the patient was in good health with no signs of recurrence.

Is lymphatic status related to regression of inflammation in Crohn's disease?

AIM:To investigate the status of the lymphatic vessels in the small bowel affected by Crohn's disease(CD) at the moment of surgery.METHODS:During the period January 2011-June 2011,25 consecutive patients affected by CD were operated on in our Institution.During surgery,Patent Blue Ⅴ was injected subserosally and the way it spread along the subserosa of the intestinal wall,through the mesenterial layers towards the main lymphatic collectors and eventually to the lymph nodes was observed and recorded.Since some patients had been undergone strictureplasty at previous surgery,we also examined the status of intestinal lymph vessels after previous strictureplasties.The same procedure was performed in a control group of 5 patients affected by colorectal cancer.Length of lesions,caliber,maximal thickness of the diseased intestinal wall,thickness of the wall at injection site and thickness of the mesentery were evaluated at surgery.RESULTS:We observed three features after the injection of Patent Blue Ⅴ in the intestinal loops:(1) Macroscopically healthy terminal ileum of patients with CD or colon cancer showed thin lymphatic vessels linearly directed toward the mesentery;(2) In mild lesions in which the intestinal wall did not reach 8 mm of thickness,we observed short,wide and tortuous lymphatic vessels directed longitudinally along the intestinal axis toward disease-free areas and then transversally toward the mesentery;and(3) Injection in the severely affected lesions,that had a thickness of the intestinal wall over 10 mm,did not show any feature of lymphatic vessels at least on the subserosal surface.There was a correlation between the thickness of the parietal wall and the severity of the lymphatic alterations.Normal lymphatic vessels were observed at previous strictureplasties in the presence of complete regression of the inflammation.CONCLUSION:Injection of Patent Blue Ⅴ in the intestinal wall could help distinguish healthy tracts of the small bowel from those macroscopically borderline.

Successful treatment of a giant ossified benign mesenteric schwannoma

Primary benign schwannoma of the mesentery is extremely rare. To date, only 9 cases have been reported in the English literature, while mesenteric schwannoma with ossified degeneration has not been reported thus far. In the present study, we present the first giant ossified benign mesenteric schwannoma in a 58-year-old female. Ultrasound, computed tomography and magnetic resonance imaging were used, but it was still difficult to determine the definitive location and diagnose the mass. By laparotomy, a 10.0 cm × 9.0 cm × 9.0 cm giant mass was found in the mesentery and was then completely resected. Microscopically, the tumour located in the mesentery mainly consisted of spindleshaped cells with a palisading arrangement. Some areas of the tumour were ossified, and a true metaplastic bone formation was observed, with the presence of bone lamellae and osteoblasts. Immunohistochemical investigation of the tumour located in the mesentery showed that the staining for the S-100 protein was strongly positive, while the stainings of SMA, CD34, CD117 and DOG-1 were negative. The cell proliferation index, measured with Ki67 staining, was less than 3%. Finally, a giant ossified benign mesenteric schwannoma was diagnosed. After surgery, the patient was followed up for a period of 43 mo, during which she remained well, with no evidence of tumour recurrence.

Mesenteric metastases from mature teratoma of the testis:A case report

Metastatic spread of testicular cancer has been well documented,with 95% of cases involving para-aortic retroperitoneal lymph nodes.Mesenteric lymphatic basins do not lie within the canonical drainage pathway of the testes and represent a rare site of metastasis.Various mechanisms of spread to the mesentery have been described,including direct extension and haematogenous dissemination.We present a case of a previously-well 43-year-old man who presented with right scrotal discomfort and intermittent lower back pain,who was found to have mesenteric metastases from a non-seminomatous germ cell tumour of the testis.Managing lymphadenopathy that lies outside of standard resection templates remains a complex surgical challenge.Here we present the first case in the English medical literature with co-existing supradiaphragmatic axillary and mediastinal nodal disease.

Effects of Yibei multi-active elements on mesenteric microcirculation in rats

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