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Nine cases of mesenteric desmoid-type fibromatosis were diagnosed and treated in Taizhou Hospital, Wenzhou Medical University between January 2010 and May 2022, including 2 females and 7 males, aged 16 to 59 years. The lesions were in the mesentery of small intestine with 7 cases, ileocecal junction with 1 cases and transverse colon with 1 case. The tumors had an unclear boundary and no envelope, the section was solid, gray and tough. The mean maximum diameter was (10.7±8.5) cm (range 3.5-33.0 cm). Microscopically, fusiform fibroblasts and myofibroblasts were parallel, bunched or staggered, buried in a large amount of extracellular collagen. The cell morphology was relatively consistent, without obvious atypia, and mitosis was rare. Immunohistochemistry showed that the tumor cells were positive for vimentin (9/9), β-catenin (9/9), while smooth muscle actin (5/9) stains were focally positive. Ki-67 proliferation index was 1%-10%. Cytokeratin Pan, S-100, STAT6, CD117, DOG1, CD34, desmin and anaplastic lymphoma kinase stains were negative. Genetic analysis showed that there were 7 cases of c.121G>A(p.Thr41Ala) mutation of CTNNB1 gene, 1 case of c.121G>A(p.Thr41Ala) and 1 case of c.134C>T(p.Ser45Phe) double mutation, and 1 case of wild type. Tumors were surgically resected in all 9 cases. Eight cases had no recurrence or metastasis, 1 case had recurrence 6 months later, and no recurrence or metastasis after additional surgical resection.

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 spindle-shaped 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., Competing Interests: Conflict-of-interest statement: The authors declare that there is no conflict of interest related to this report.

Flavanols are metabolized in the small intestine and the liver to produce their glucuronidated, sulfated or methylated conjugates that can be body distributed or excreted in the urine. However, the intake of large amounts of flavanols is not directly related to their bioavailability. This study aims to investigate the administered dose dependence of flavanols' conjugation and body distribution. In this study, different doses of a grape seed proanthocyanidin extract (GSPE; 125, 250, 375 and 1000 mg/kg) were orally administered to male Wistar rats. Tissues were collected 2h after GSPE administration. Flavanols were quantified by HPLC-MS/MS. Results show that the majority of GSPE metabolites are located in the kidney, followed by the liver. Lower concentrations were found in mesenteric white adipose tissue (MWAT) and the brain. Moreover, flavanol metabolites followed a tissue-specific distribution pattern independent of dosage. In the kidney, glucuronidated metabolites were the most abundant; however, in the liver, it was mainly methyl-glucuronidated metabolites. In MWAT, free flavanols were dominant, and methylated metabolites were dominant in the brain. Concentration within a tissue was dependent on the administered dose. In conclusion, flavanol metabolites follow a tissue-specific distribution pattern and only the tissue concentration of flavanol metabolites is dependent on the administered dose., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Epithelioid hemangioendothelioma (EHAE) is a malignant vascular tumor derived from endothelial cell often misdiagnosed as Hepatic carcinoma on the basis of radiological features. Till now etiology of this rare curiosity is unknown but it is related with use of oral contraceptives pills (OCP), liver trauma, exposure to vinyl chloride and hepatitis. We herein report on a case which failed to be diagnosed by cytopathology, computed tomography (CT) and magnetic resonance imaging (MRI). Patient was a 46 yr old man presented with abdominal distension for a month. Initial liver function test (LFT) was increased whereas renal function test (RFT) and alpha-fetoprotein (AFP) were normal. His abdominal ultrasound revealed multiple hypoechoic nodules and multiple liver calcifications. Subsequently laparoscopic omental biopsy and Ultrasound guided liver biopsy was done showing the neoplastic cells scattered in fibrous stroma. The immunohistochemistry for endothelial tumor cells stained positive for Vimentin (+++), CD10 (+++), CD34 (++), CD31 (+), Factor VIII antigen (focal) (+) and low proliferative activity for ki-67. Our case is very interesting in which patient admitted with nonspecific symptoms of abdominal pain and diagnosed to be a Malignant Hepatic EHAE metastasized to the peritoneum, omentum and mesentery. The patient was on thalidomide 50 mg/day and increased to 100 mg/day. 5-Flurouracil (FU) intraperitoneal chemotherapy and other symptomatic and supportive treatment was given to the patient. Our case highlights on the importance of immunohistopathological diagnosis, compare the radiological findings of this disease and discuss the treatment strategy with review of available literature.

Perivascular epithelioid cell tumor (PEComa) is a rare entity originating from mesenchymal tissue, which stains for both melanocytic and smooth muscle markers. We would like to present an unusual case of the PEComa of the mesentery which was unexpected discovery in a female patient with colonic adenocarcinoma. The tumour was revealed on the computer tomography and then resected during surgery, with subsequent chemotherapy for the colon adenocarcinoma. Furthermore we would like to discuss PEComa biology, emphasizing histological criteria of malignancy, possible treatment options and differential diagnosis which is mostly based on immunohistochemistry. Virtual slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1809062291157051 .

The purpose of this study was to quantitatively clarify the effect of alky-chain length of a triglyceride in an emulsion on the partitioning of highly lipophilic compounds into the lymph fluid after their oral administration. Highly lipophilic anthraquinone derivatives were orally administered in emulsions to rats. Emulsions composed of long-, medium-, and short-chain triglycerides (LCT, MCT, and SCT emulsions, respectively) were used. The concentrations of the compounds in plasma and lymph fluid were periodically determined and their partitioning to the lymph was calculated using a mathematical model. Intestinal absorption of all compounds was enhanced and the plasma concentrations of the compounds were found to be in the following order: LCT emulsion > MCT emulsion > SCT emulsion. The amounts of each compound recovered in the lymph were not in agreement with their lipophilicity. Quantitative analysis revealed that the partitioning of the compounds to the lymph may be determined by the solubility of the compound in the triglyceride in the form of an emulsion and the amount of triglyceride transferred to the lymph fluid. These results suggest a possibility that the amount of a compound absorbed via the lymph route after oral administration can be quantitatively controlled by the formulations.

Perivascular epithelioid cell tumor (PEComa) is a rare but distinct mesenchymal neoplasm composed of histologically and immunohistochemically unique perivascular epithelioid cells. Due to its relative rarity, little is known about the histogenesis and prognostic factors of this tumor. We describe a case of unusual mesenteric PEComa in a 38-year-old female patient with regional lymph node involvement. Histologically, the tumor was composed of sheet of epithelioid cells with abundant clear or eosinophillic cytoplasms. Extensive coagulative necrosis and a few mitotic figures (2/50 high power field) could be found in tumor. The epithelioid tumor cells were diffusely positive for HMB-45, Melan-A, and focally positive for calponin. One of enlarged mesenteric lymph nodes was observed to be involved by tumor. A diagnosis of malignant mesenteric PEComa with lymph node involvement was made. The patient received chemotherapy after total resection of tumor and segmental resection of involved jejunum. There was no sign of recurrence of tumor found in period of 6-month regular follow-up after chemotherapy. To our knowledge, this is the first case of malignant PEComa in mesentery accompanied with regional lymph node involvement. The literature on this rare tumor is reviewed and diagnostic criteria of malignant PEComa are discussed., Virtual Slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1309992178882788.

Background: Lymphatic and blood microvascular systems play a coordinated role in the regulation of interstitial fluid balance and immune cell trafficking during inflammation. The objective of this study was to characterize the temporal and spatial relationships between lymphatic and blood vessel growth in the adult rat mesentery following an inflammatory stimulus., Methods and Results: Mesenteric tissues were harvested from unstimulated adult male Wistar rats and at 3, 10, and 30 days post compound 48/80 stimulation. Tissues were immunolabeled for PECAM, LYVE-1, Prox1, podoplanin, CD11b, and class III β-tubulin. Vascular area, capillary blind end density, and vascular length density were quantified for each vessel system per time point. Blood vascular area increased compared to unstimulated tissues by day 10 and remained increased at day 30. Following the peak in blood capillary sprouting at day 3, blood vascular area and density increased at day 10. The number of blind-ended lymphatic vessels and lymphatic density did not significantly increase until day 10, and lymphatic vascular area was not increased compared to the unstimulated level until day 30. Lymphangiogenesis correlated with the upregulation of class III β-tubulin expression by endothelial cells along lymphatic blind-ended vessels and increased lymphatic/blood endothelial cell connections. In local tissue regions containing both blood and lymphatic vessels, the presence of lymphatics attenuated blood capillary sprouting., Conclusions: Our work suggests that lymphangiogenesis lags angiogenesis during inflammation and motivates the need for future investigations aimed at understanding lymphatic/blood endothelial cell interactions. The results also indicate that lymphatic endothelial cells undergo phenotypic changes during lymphangiogenesis.

Scope: Evidence suggests a neutral to beneficial role of certain trans fatty acids (TFA) from natural ruminant sources. Trans11-18:1 (vaccenic acid, VA), the most predominant ruminant TFA and a precursor to conjugated linoleic acid, has been shown to improve atherogenic dyslipidemia and symptoms of hepatic steatosis in animal models. The objective of this study was to assess the intestinal bioavailability of various VA sources including synthetic free fatty acid (FFA) and natural ruminant triglyceride forms, as well as the mechanistic pathways that mediate VA's bioactivity., Methods and Results: VA acts as a partial agonist to both peroxisome proliferator-activated receptors (PPAR)-α and PPAR-γ in vitro, with similar affinity compared to commonly known PPAR agonists. It was further confirmed that VA at 30 and 100 μM concentrations suppressed cardiomyocyte hypertrophy vitro in a PPAR-α- and PPAR-γ-dependent manner. In vivo, feeding of VA (1%, w/w) resulted in increased mRNA and protein expression of PPAR-γ in the mucosa of JCR:LA-cp rats, a model of the metabolic syndrome (p < 0.01 and p < 0.05, respectively) compared to control. In addition, VA from a triglyceride source had greater intestinal bioavailability in vivo compared to VA provided in an FFA form (p < 0.01)., Conclusion: The activation of PPAR-α- and PPAR-γ-dependent pathways provides a mechanistic explanation of how VA improves blood lipids and related metabolic disorders during conditions of hyperlipidemia. This report also supports the consideration of differential reporting of industrially produced versus natural TFA on food nutrient labels., (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Primo-vessels have been observed in the rat abdominal cavity as floating thread like structures on and not adhering to fascia-wrapped internal organs. To date their presence, locations, and lengths have been irregular and unpredictable, and their identification not regularly repeatable, thus they have remained a nagging enigma in primo-vascular system research for several years. In this work, locations were found where primo-vessels were regularly present and observed repeatedly. These vessels were not floating or freely movable but lay in a regular position in the mesentery in the abdominal cavity of the rat, being observed between the cecum and small intestine and between the colon and mesentery root. The difference between a lymph vessel and a primo-vessel is described in anatomical and histological aspects. In addition, trypan blue was found to enter primo-vessels through the surrounding membranes and filled spaces between fibers comprising the primo-vessels. It is conjectured that the previously observed floating primo-vessels had anomalously and irregularly emerged, for some unknown physiological reasons, from primo-vessels normally located in the fascia-like mesentery., (Copyright © 2010 Korean Pharmacopuncture Institute. Published by .. All rights reserved.)

The aim of this study was to investigate the spatiotemporal development of autonomic nerve fibers and primordial germ cells (PGCs) along their migratory route from the dorsal mesentery to the gonadal ridges in human embryos using immunohistochemical markers and electron microscopy. Autonomic nerve fibers in the dorsal mesentery, the pre-aortic and para-aortic plexuses and in the gonadal ridge were stained for beta III tubulin, neuron specific enolase and the glia fibrillary acidic protein. Electron microscopy demonstrated the presence of neurofilaments and neurotubules in these nerve fibers and their intimate contact with PGCs. PGCs expressed GAGE, MAGE-A4, OCT4 and c-Kit. Serial paraffin sections showed that most PGCs were located inside bundles of autonomic nerve fibers with the majority adjacent to the most peripheral fibers (close to Schwann cells). We also show that both nerve fibers and PGCs arrive at the gonadal ridge between 29 and 33 days pc. In conclusion, our data suggest that PGCs in human embryos preferentially migrate along autonomic nerve fibers from the dorsal mesentery to the developing gonad where they are delivered via a fine nerve plexus.

Background: The free intestinal flap has become a recognized part of the surgical armamentarium for the reconstruction of the cervical esophagus and in the treatment of severe short bowel syndrome. However, the intestinal flap is difficult to monitor postoperatively and is susceptible to ischemia. Entire avoidance of neglected ischemia and false alarms require a monitoring system with sensitivity and specificity of 100%. The aim of this study was to investigate the value of microdialysis (MD) as a monitoring method for detecting ischemia in intestinal transplants., Methods: In 12 pigs the entire small intestine was divided into three segments, each isolated on a vascular pedicle consisting of one artery and one vein. For metabolic monitoring of the intestinal segments, one CMA 63 MD catheter was placed in each segment in the mesentery just at the border of the intestinal wall. After 1 h of arterial ischemia followed by 2 h of reperfusion, the three intestinal segments in each pig were allocated to arterial ischemia, venous ischemia, or no ischemia. A total of 10 control segments, 10 segments with arterial ischemia, and nine segments with venous ischemia were provided for evaluation of metabolic changes., Results: One hour of secondary ischemia induced considerable metabolic changes, with a decrease in the concentration of glucose (C (Glucose)) followed by an increase in the concentration of lactate (C (Lactate)) as well as in the lactate:pyruvate (L/P) and lactate:glucose (L/G) ratios. The changes became even more pronounced after 1(1/2) h when the L/P and L/G ratios had increased 9 and 30 times, respectively, in the ischemic segments and without overlap in values between the ischemic and the nonischemic segments. When using C (Glucose) < 0.2 mmol/l or L/G > 50 as cutoff levels for detection of ischemia, a sensitivity and a specificity of 100% could be achieved. An increase in C (Glucose) of more than 2 mmol/l, after the infusion of glucose, could be used as a challenge test to exclude ischemia., Conclusions: A monitoring system based on the determination of the C (Glucose) and C (Lactate) by using microdialysis can be used for positive differentiation between ischemic and nonischemic intestinal segments.

Differential protein profiling by 2-D PAGE is generally useful in biomarker discovery, proteome analysis and routine sample preparation prior to analysis by MS. The goal of this study was to compare 2-D PAGE-resolved protein profile of lymphatic endothelial cells to those of venous, and arterial endothelial cells isolated from lymphatic and blood vessels of bovine mesentery (bm). Three 2-D PAGE electrophoretograms were produced for each of the three cell types and quantitatively analyzed. Protein identification by LC-MS/MS was performed to identify 39 proteins found to be present at statistically significantly different levels in the three cell types (p<0.05). Most of the 39 proteins have not been previously reported in EC proteomic studies of 2-D PAGE electrophoretograms. Three proteins, HSPA1B (HSP70 family member), HSPB1 (HSP27 family member), and UBE2D3 (a member of E2 ubiquitin-conjugating enzymes) found to be at highest levels in bm arterial endothelial cells, bm venous endothelial cells, and bm lymphatic endothelial cells, respectively, were validated by immunoblotting with appropriate antibodies. The lack of substantial overlap between our results and those of other groups' comparative studies are discussed. Functional implications of differences in levels of various proteins identified in the three cell types are also discussed.

Although the flavonol quercetin is intensively investigated, our knowledge about its bioavailability and possible target organs is far from being complete. The aim of this study was to check the potential of quercetin to accumulate in various tissues after long-term dietary treatment compared with a single treatment with flavonol. Pigs ingested either a single dose of quercetin aglycone (25 mg/kg body weight; Expt. 1) or received the flavonol twice a day at the same dose mixed into their regular meals (i.e 50 mg.kg(-1).d(-1)) for 4 wk (Expt. 2). In both experiments, we took plasma and tissue samples 90 min after the final meal and analyzed them using HPLC. Additionally, the specific activity of the enzyme beta-glucuronidase was measured in selected tissues. Higher flavonol concentrations than in plasma were found in only the liver (Expt. 1) or the intestinal wall and kidneys (Expt. 2). All tissues except blood plasma contained a variable amount of deconjugated quercetin in the range of 30-100% of total flavonols. However, the specific beta-glucuronidase activity was not correlated with the proportions of deconjugated flavonols in the various tissues. Long-term dietary intake of the flavonol did not lead to a greater accumulation in any tissue compared with the single treatment. Flavonol concentrations only exceeded the plasma concentration within organs involved in its metabolism and excretion, including liver, small intestine, and kidneys.

The purpose of the present study was to determine if exercise trained rats might benefit from protection against fat accumulation in response to an obesity stimulus initiated upon training cessation. Two groups of female rats were either treadmill trained for 8 weeks (DTr) or remained sedentary (Sed). They were then submitted either to a high-fat diet (HF; 42 E%) or kept on a standard diet (SD; 12.5 E% lipids) for another 6 weeks while remaining sedentary. Fat accumulation in liver and adipocytes along with fat-cell diameter and plasma free fatty acid (FFA) levels were measured 0, 2, and 6 weeks after training cessation. Immediately after the training period (t = 0), DTr rats exhibited similar body mass and higher dietary intake but smaller body fat content (4 fat pads) compared with Sed rats. DTr rats, under both diets, exhibited higher gains in body fat than Sed rats (DTr vs. Sed, 71% vs. 8% and 132% vs. 55% for SD and HF, respectively), such that fat mass in all 4 depots was similar to Sed rats 6 weeks after training cessation. Despite higher adipocyte fat accretion, liver lipid infiltration was not increased in DTr animals and plasma FFA levels were lower throughout the detraining period. In addition, plasma leptin levels remained lower in DTr animals throughout the detraining period under the HF diet condition. The present results indicate that previously exercise trained rats are not protected against adipocyte fat accumulation whether they ingest a standard or a high-fat diet.

Poor growth during parasitic infection may be due to a redistribution of amino acids away from skeletal muscle protein synthesis to the intestinal site of infection. The effect of a Trichostrongylus colubriformis infection on whole-body amino acid kinetics and tissue fractional protein synthesis rates were determined in lambs fed fresh Sulla (Hedysarum coronarium; 800 g DM/d). Lambs were dosed with 6000 L3 Trichostrongylus colubriformis larvae daily for 6 d (n 6) or kept as parasite-free controls (n 6). On day 45 post-infection, the lambs received an intravenous injection of 2H2O and infusions (8 h) of [35S]sulphate to measure the size of the whole-body water and sulphate pools, respectively. On day 48, the lambs were continuously infused for 8 h with [3,4-3H]valine into the jugular vein as well as with [1-13C]valine and [35S]cysteine into the abomasum. After the 8 h infusions, the lambs were killed and tissue samples collected from the duodenum, ileum, mesenteric lymph nodes, liver, spleen, thymus, muscle and skin. Feed intake (769 v. 689 (sd 47) g DM/d) was not affected by infection, whereas liveweight gains (50 v. -50 (sd 70) g/d) were lower and intestinal worm burdens (240 v. 18,000 (sd 7000) worms) higher in the infected lambs. Parasitic infection increased the fractional protein synthesis rates in the small intestine, mesenteric lymph nodes and liver but did not affect skin and skeletal muscle fractional protein synthesis rates during the established parasitic infection.

Background: Familial adenomatous polyposis (FAP) arises following mutation or loss of the adenomatous polyposis coli (APC) gene. Desmoid tumours are proliferations of fibroblasts and occur as an extracolonic manifestation of FAP. They are a leading cause of death after colectomy. The aim of this study was to assess the potential for APC gene transfer into fibroblasts in vitro and in vivo as a basis for consideration of gene therapy in the prevention or treatment of desmoid tumours., Methods: The APC gene was transferred by lipofection into fibroblasts in tissue culture and into peritoneum and small bowel mesentery in vivo. Reverse transcriptase-polymerase chain reaction was used to determine whether or not transfection was successful., Results: Transgene expression was recorded in vitro to 7 days after transfection. High levels of transgene expression were also seen in samples of peritoneum (all eight mice), small bowel mesentery (seven of eight), liver (seven of eight) and intestinal tissues (five to six of eight) following intraperitoneal treatment. Interestingly, transgene expression in gonadal tissues was occasionally noted., Conclusion: Liposomal transfection of APC gave prolonged high-level expression of the transgene, an important basis for gene therapy. No adverse effects were recorded. Further work is needed in animal models of desmoid disease to assess the clinical effects of gene therapy.

The zinc finger transcription factor Gata4, is associated with gonadal development in many species. The present study characterizes temporal and spatial localization of Gata4 throughout gonadogenesis in porcine embryos. Immunohistochemical studies illustrated that Gata4 protein is present in the coelomic epithelium prior to histological differentiation of the nascent bipotential gonad, marking the future site of both XX and XY porcine gonads. Many somatic cells of both XX and XY bipotential gonads continue to retain Gata4 immunoreactivity throughout sexual differentiation and subsequent gonadal development. Testicular cords were evident by 26 days postcoitum. Gata4 was present in Sertoli cells, identified by virtue of coexpression with Müllerian inhibiting substance and also interstitial cells including Leydig cells throughout fetal and postnatal life. Many somatic cells of the differentiating ovary including follicular cells also contained Gata4 protein throughout fetal and postnatal life. Gata4 was not present in germ cells, endothelial cells, or other undifferentiated mesenchymal cells of both XX and XY gonads. A population of Gata4-positive cells in the dorsal mesentery was continuous with the coelomic epithelium of the gonad. This localization pattern led to the hypothesis that a subpopulation of somatic cells in the dorsal mesentery moves toward the gonad. An in vitro cell migration assay demonstrated that Gata4-positive cells preferentially migrate toward explanted gonadal tissue, and morphological features of the developing gonad supported this hypothesis. This study illustrates that Gata4 is a very early marker for gonad formation, highlights species differences in temporal and spatial localization patterns, and suggests a potential role for Gata4 in the development of both XX and XY porcine gonads. Further, we suggest that mesenchymal cells of the dorsal mesentery may provide a source of somatic cells that migrate and incorporate into the gonad and contribute to various somatic cell lineages. Overall, the spatial and temporal localization patterns of Gata4 during porcine gonadogenesis implies a much earlier and wider role for Gata4 than previously reported in other species.

Asbestos fibers in occupationally exposed individuals relocate from the lung to extrapulmonary sites. A mechanism for relocation is via the lymphatic circulation. Indeed, asbestos fibers have been found in lymph nodes as well as pleural plaques. Our laboratory has recently shown that asbestos fibers also reach the mesentery and omentum in the peritoneal area where a small percentage of mesotheliomas occurs in exposed individuals. The present study uses light and analytical transmission electron microscopy for defining the asbestos burden in digested lung, omentum, and mesentery tissues from individuals considered as representing the general population in East Texas. The findings, when compared with previous data from occupationally exposed individuals, indicate extreme contrasts as to the level and types of fiber burden between individuals representing the groups.

A case of a uterus-like mass arising from the mesentery is reported. A mass measuring 14x11 cm was noted in the small bowel mesentery of a 59-year-old woman. Histologically, the lesion consisted of endometrial-type and fallopian tube-type mucosa surrounded by thick bundles of smooth muscle cells. Since the first report by Cozzutto in 1981, 10 cases of uterus-like mass, that included seven ovarian and three extraovarian cases, have been reported. To our knowledge, the present lesion was the first case originating from the mesenteric region. Three hypotheses of this rare lesion: (i) congenital anomaly; (ii) metaplasia; and (iii) heterotopia theories are reviewed.

We previously reported that the mouse GATA-2 gene is regulated by two alternative promoters (Minegishi et al, J Biol Chem, 273:3625, 1998). Although the more proximal IG (general) promoter is active in almost all GATA-2-expressing cells, the distal IS (specific) promoter activity was selectively detected in hematopoietic tissues but not in other mesodermal tissues. We report here in vivo analysis of the GATA-2 locus and its regulatory characteristics in hematopoietic tissues of transgenic mice. Transgenes containing 6 or 7 kbp of sequence flanking the 5' end of the IS first exon direct expression of beta-galactosidase or green fluorescent protein (GFP) reporter genes specifically to the para-aortic splanchnopleura, aorta-gonads, and mesonephros (AGM) region, and in the neural tissues. In situ hybridization analysis showed that reporter gene expression specifically recapitulates the endogenous expression profile of GATA-2 in these tissues. The flk-1, CD34, c-kit, and CD45 antigens were identified in the GFP-positive cells from the AGM region and fetal liver, indicating that GATA-2 is expressed in immature hematopoietic cells. Deletion of 3.5 kbp from the 5' end of the 6.0 kbp IS promoter construct, including one of the DNase I hypersensitive sites, completely abolished hematopoietic expression. These experiments describe an early developmental GATA-2 hematopoietic enhancer located between 6.0 and 2.5 kbp 5' to the IS exon.

Type VI collagen was immunolocalized in several soft connective tissues at the light and electron microscopic level. Positive labeling was found in all tissues examined, periodontal ligament, gingiva, mesenterium and periosteum. The labeled structures could be divided into 2 categories: microfibrils intermingling with collagen fibrils, and those that formed bundles (oxytalan fibres and elastin-associated microfibrils). Control sections incubated with antibody preabsorbed to purified type VI collagen, or with non-immune antibody, proved to be negative. Our observations indicate that the structural organization of type VI collagen varies from small microfibrillar structures associated with the collagen and elastin fibre systems to highly ordered parallel arrays of oxytalan bundles.

Human peritoneal dialysis effluent (PDE) contains a phosphatidylcholine-rich compound similar to the surfactant that lines lung alveoli. This material is secreted by mesothelial cells. Lung surfactant is also characterized by four proteins essential to its function. After having long been considered as lung-specific, some of them have been found in gastric and intestinal epithelial cells. To explore further the similarity between lung and peritoneal surfactants, we investigated whether mesothelial cells also produce surfactant proteins. We used rat transparent mesentery, human visceral peritoneum biopsies and PDE. Surfactant proteins were searched for after one- and two-dimensional SDS/PAGE and Western blotting. On a one-dimensional Western blot, bands at 38 and 66 kDa in rat mesentery, and at 38 and 66 kDa in human peritoneal mesothelial cells (in vivo and in vitro) and PDE, corresponded to monomeric and dimeric forms of lung surfactant protein A (SP-A). On two-dimensional Western blots, the 32 and 38 kDa spots in mesentery and PDE localized at the acidic pH appropriate to the SP-A monomer's isoelectric point. SP-D was also identified at the same 43 kDa molecular mass as in lung. SP-B was not detected in mesenteric samples. Expression of SP mRNA species was also assessed by reverse transcriptase-PCR, which was performed with specific primers of surfactant protein cDNA sequences. With primers of SP-A and SP-D, DNA fragments of the same size were amplified in lung and mesentery, indicating the presence of SP-A and SP-D mRNA species. These fragments were labelled by appropriate probes in a Southern blot. No amplification was obtained for SP-B. These results show that mesentery cells produce SP-A and SP-D, although they are of embryonic origin (mesodermal) and are different from those of the lung and digestive tract (endodermal) that secrete these surfactants.

Neuronal circuitry between the inferior mesenteric ganglion (IMG) and the distal colon as well as the rectum, forming the intestino-intestinal reflex pathway, was investigated in the dog using immunohistochemistry combined with retrograde tract tracing and denervation experiments. Virtually all IMG neurons were tyrosine hydroxylase (TH)-immunoreactive. Of these ganglionic neurons, about 64% were also immunoreactive for calbindin (Calb), some 35% for neuropeptide Y (NPY), and 2% for vasoactive intestinal peptide (VIP). The retrograde tracer experiments revealed that both Calb/TH neurons and NPY/TH neurons projected to the distal colon and the rectum. In these intestinal walls, Calb/TH positive varicose fibers were found in the myenteric and submucous ganglia as well as in the longitudinal muscle layer, while NPY/TH positive fibers were mainly distributed around the vascular walls. Around Calb/TH neurons of the IMG, abundant varicose nerve fibers immunoreactive for VIP, dynorphin (DYN), calcitonin gene-related peptide (CGRP), enkephalin (ENK), substance P (SP) and bombesin (BOM) were distributed. These immunoreactive fibers disappeared after the total denervation of the IMG. After the application of Fast Blue into the IMG or distal stumps of transected lumbar colonic and hypogastric nerves, retrogradely labeled neurons occurred in the myenteric plexus with increasing density along the distal colon and rectum, and were immunoreactive for VIP, DYN, CGRP, ENK, SP or BOM. Double immunostaining of nerve fibers in the distal stumps of the ligated colonic and hypogastric nerves revealed the presence of viscerofugal fibers containing VIP with DYN and/or CGRP and those containing ENK with SP and/or BOM. These results demonstrate for the first time that the efferent limb of the canine intestino-intestinal reflex arch via the IMG consists of Calb-immunoreactive ganglion neurons projecting to the longitudinal muscles in addition to the enteric plexus of the lower intestine and also of NPY-immunoreactive ganglion neurons projecting to the intestinal blood vessels, and that the afferent limb is composed of at least two discrete groups with different peptide contents, i.e., myenteric neurons containing VIP with DYN and/or CGRP and those containing ENK with SP and/or BOM.

Background: Graft-versus-host disease (GVHD) occurs in the recipient after small bowel transplantation (SBT). Proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), and interleukin 6 (IL-6), may be important mediators of GVHD. Increased expression of these cytokines might precede the clinical manifestations of GVHD induced by SBT., Methods: Heterotopic SBT was performed using Lewis donors into Lewis x Brown Norway F1 (LBN-F1) recipients. The isograft control was performed from LBN-F1 into LBN-F1. Animals were killed on the 5th and 11th postoperative day (POD). mRNA was isolated from recipient native small bowel, colon, spleen, liver, and mesenteric lymph nodes and from nonsurgical controls as baseline. Semiquantitative reverse transcriptase polymerase chain reaction was performed to amplify mRNA transcripts for TNF-alpha, IFN-gamma, and IL-6 using alpha32P-dATP incorporation. Clinical signs, histologic assessment, and cytokine expression were correlated., Results: On POD 5, there were neither clinical signs nor histologic features of GVHD, but mRNA expression of TNF-alpha and IL-6 in small bowel, IL-6 in spleen, and IFN-gamma in mesenteric lymph nodes were significantly increased in allograft animals when compared with normal and isograft tissues. On POD 11, both the clinical signs and histologic features of GVHD were seen, and TNF-alpha and IL-6 in native small bowel, TNF-alpha in colon, IFN-gamma in spleen, and IL-6 in mesenteric lymph nodes were significantly increased in allograft animals when compared with that in normal and isograft tissues., Conclusions: In conclusion, TNF-alpha, IFN-gamma, and IL-6 expression precede clinical onset and histologic evidence of GVHD in specific tissues. Therefore, increased expression of these cytokines is correlated with the development of GVHD in this model of SBT.

3,3'-Diaminobenzidine, in the presence of manganese and cobalt ions, was applied for the detection of superoxide anions in unfixed cryostat sections of rat oesophagus, trachea, skin and intact mesenterium. In all connective tissues, a blue final reaction product was found in a granular form in mast cells. The amount of final reaction product formed after incubation with diaminobenzidine and cobalt ions was increased by the addition of manganese ions. Electron microscopical analysis revealed that the electron-dense final reaction product was exclusively present in the granules of mast cells and on elastin fibres. It was found that the constitutive spontaneous formation of final reaction product in mast cells was enzymatic and dependent on the presence of oxygen in the medium. Of all the enzyme inhibitors and free radical scavengers tested, only azide strongly reduced the amount of final reaction product. It was concluded that the reaction was partly caused by peroxidase activity, but that superoxide anions are also constitutively and spontaneously produced in mast cell granules. The exact enzymatic source could not be established. Whether this property of mast cell granules plays an antimicrobial role in connective tissues can only be speculated.

We have studied the possibility of associating fluorescence microscopy and hematoxylin-eosin staining for the identification of elastic fibers in elastin-rich tissues. Elastic fibers and elastic laminae were consistently identified by the proposed procedure, which revealed itself to be easy and useful for the determination of such structures and their distribution. The fluorescence properties of stained elastic fibers are due to eosin staining as revealed by fluorescence analysis of the dye in solution, with no or only minor contribution by the elastin auto-fluorescence. The main advantage of this technique resides in the possibility of studying the distribution of elastic fibers in file material without further sectioning and staining. The use of the confocal laser scanning microscope greatly improved the resolution and selectivity of imaging elastic fibers in different tissues. The determination of the three-dimensional distribution and structure of elastic fiber and laminae using the confocal laser scanning microscope was evaluated and also produced excellent results. used to discriminate calcified bone and elastic fibers using the fluorescence microscope (Bradbeer et al. 1994). The selective fluorescence exhibited by these two main tissue components is based on the very faint eosin staining, while intensely eosinophilic substrates and those stained with the highly absorbing basic dyes show no fluorescence or just a very faint signal. Considering the possibility of using eosin fluorescence for the selective identification of some tissue components, we have extended this approach to the study of elastic fibers in hematoxylin-eosin (H&E) preparations. This paper then describes the results of observations with the fluorescence microscope of some H&E stained sections and evaluates the use of the confocal laser scanning microscope to image elastic fibers in the same preparations. Furthermore, we have also studied absorption and fluorescence spectra of eosin and phloxine, a closely related dye, in solution, to correlate them with the fluorescence detected in tissue sections.

Adenocarcinoma of the small intestine was found in a 6-year-old clouded leopard. This tumour was characterized by the presence of goblet and neuroendocrine cells. The latter were labelled positively for either serotonin, somatostatin, neurotensin, gastrin or secretin. These neuroendocrine cells were reduced in number in most of the metastatic lesions, including those of the mesentery, diaphragmatic pleura, lungs, liver and heart, and squamous metaplasia was detected in some metastatic sites.

The mouse ovarian ascites tumor, MOT, and mammary ascites tumor, TA3/St, served as models to follow changes in hyaluronan levels during tumor growth, attachment, and invasion. Subsequent to introduction of tumor cells into the peritoneal cavity, hyaluronan accumulated intraperitoneally and at the initial sites of attachment of tumor cells and cell clumps to the mesenteric surface; the latter co-localized with sites of fibrin deposition as reported earlier. Subsequently, high levels of hyaluronan accumulated throughout the interior of the mesentery. Because neither tumor cell line synthesized substantial amounts of hyaluronan in culture, the large accumulations observed in the mesenteries and ascites fluid of tumor-bearing animals most likely resulted from increased synthesis and secretion by peritoneal-lining mesothelial cells and/or fibroblasts in response to stimulation by the tumor cells or their products. TA3/St tumor cells were universally positive for the hyaluronan receptor, CD44, whereas approximately 90% of MOT tumor cells were CD44-negative. However, the great majority of MOT or TA3/St cells that initially attached to the mesentery were strongly CD44 positive. We propose that hyaluronan-rich matrix is involved in tumor cell attachment to the mesentery possibly via interaction with tumor cell surface CD44.

Nitric oxide free radical is a presumed neurotransmitter of the gastrointestinal tract. It can play an important role in the relaxation of the smooth muscles. We used nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemistry and the localization and morphology of the NADPH-d positive neural elements of the different areas were compared in the cat. NADPH-d positive neurons could be found mainly in the myenteric plexus but some of them were located in the submucous plexus and in the inner circular muscle layer as well as around the blood vessels. The greatest number of the positive neuronal cell bodies could be seen in the myenteric plexuses of the sphincter regions. Stained nerve fibers were seen mainly in the inner circular muscle layer. These results suggest that the positive neurons of the sphincter regions can have an important role in the relaxation. NADPH-d positive neuronal elements of the submucous plexus were located around blood vessels and can regulate the blood flow and secretion of the glands or it is also possible that they belong to the sensory neurons.

2,2-Dimethyl-N-(2,4,6-trimethoxyphenyl)dodecanamide (I, CI-976) has been determined in rat mesenteric lymph and plasma using a rapid and sensitive high-performance liquid chromatographic method. The samples prepared from plasma and lymph by liquid-liquid extraction were analysed on a reversed-phase C18 column isocratic conditions and ultraviolet detection. The method was applied to the determination of levels of I in Wistar rats after intraduodenal administration of 110 mg/kg of I as a lipid emulsion.

Epidermal growth factor (EGF) is known to stimulate wound repair, including connective tissue repair as observed in the perforated rat mesentery. In the present study we assessed changes in expression of EGF receptors during healing of connective tissue by measuring the binding of [125I]EGF to perforated and unperforated mesenteric membranes. Autoradiographic grain density was measured on flat mounted or sectioned mesenteric tissue. Laparotomy alone caused an inflammatory reaction in the abdominal cavity and significantly (p < 0.04) increased the binding of [125I]EGF to unperforated membranes by 70% on days 1 and 3 postoperatively. In perforated mesenteric membranes, the binding of EGF in a 1 mm wide zone around the incision was significantly higher (p < 0.05) than EGF binding in the adjacent tissue on days 3 through 7. Furthermore, the average grain density in a 100 microns wide segment around the incision was approximately twice as high (p < 0.008) as the grain density in the mesentery 100 to 500 microns around the incision or in adjacent tissue (p < 0.004). These results indicate that expression of EGF receptor increases in the region of regenerating connective tissue and supports the hypothesis that EGF receptor plays a key role in mesenteric wound healing.

A new double-embedding technique for thin tissue membranes is presented. This technique is useful for thin membranes such as mesenteric membranes from rodents, which usually measure only 10 microns in thickness. Several membranes are fixed and mounted on four needles located at the bottom of a plastic box. The box is filled with agarose at 50 C and then allowed to solidify. The agarose block is then removed, dehydrated in alcohol, cleared with HistoPetrol (isoparaffin hydrocarbons), permeated with paraffin and sectioned. The morphology is comparable to that obtained with methacrylate plastic embedding but is less time-consuming, less hazardous since no plastic hardener and activator are used and makes immunohistochemical studies easier.

This study measured the adrenergic receptor response of 13 patients with severe intra-abdominal sepsis, who required laparotomy and an open abdominal closure with Marlex mesh. The source of the sepsis was gram-negative organisms of intestinal origin. There were seven survivors and six nonsurvivors. When the patients were stratified into survivors and nonsurvivors, the Septic Severity Score, the APACHE II score, the Acute Physiological Score, and the Glasgow Coma Scale score results were not significantly different between groups. The alpha-2 and beta-1 adrenergic receptor responses were measured in the adipose tissue of the abdominal wall and the small bowel mesentery on day 1 of admission to the intensive care unit. The results demonstrated that the alpha-2 and beta-1 receptors of the nonsurvivors had a significantly decreased receptor response with desensitization and down regulation. The alpha-2 and beta-1 receptors of the survivors had an increased response with hypersensitization and up regulation. This study indicates that the adrenergic receptor pattern is distinctly different between survivors and nonsurvivors with severe abdominal gram-negative sepsis. The pattern differences occurred early (within 24 hours) when the patients had similar physiologic profiles. It is concluded that adrenergic receptor response may be a biologic indicator of the magnitude of the septic injury and a predictor of outcome.

On the model of E. coli-induced acute infectious peritonitis in rats it is established that the mast cell reaction and histamine level increase in exudate and inflamed mesentery tissue are biphase and are observed predominantly following the inflammatory agent action, in the period corresponding to the immediate phase of peritoneal cavity vessel permeability increases. The preliminary elimination of mast cells significantly inhibits a rise in the vascular permeability in the immediate phase and slightly affects the delayed phase, thus prolonging exudation. At the same time the dynamics of free histamine indicates its direct involvement in mediation and/or modulation as well as in subsequent inflammatory events. The common rules of mast cell involvement and vascular permeability increase in infectious and aseptic inflammation have been shown.

By in situ hybridization with biotinylated human interleukin 1 alpha (IL-1 alpha) cDNA probe, distribution of feline IL-1 alpha mRNA-expressing cells was examined in the tissues from 49 cases diagnosed as feline infectious peritonitis (FIP) by pathological examination. IL-1 alpha mRNA-expressing cells were found in visceral peritoneum, lymphoid organs, liver, kidney, pancreas, digestive tract, lung, pleura, brain, palpebral conjunctiva, and bone marrow. Hybridization signals for IL-1 alpha mRNA were mostly located in the local inflammatory lesions on the serosal surface of various organs and omentum, which were frequently involved in the lesions of FIP (27.8 +/- 5.1 cells/mm2). Morphological examination suggested that they were infiltrated macrophages. However, few IL-1 alpha mRNA-expressing macrophages were in the lesions of other organs. These data suggested that IL-1 alpha produced from macrophages in the local inflammatory sites might participate in the initiation and development of the lesions on the visceral peritoneum in FIP.

A close microanatomical relationship between serotonin-positive mast cells and nerve fibres positive for substance P, calcitonin gene related peptide, vasoactive intestinal polypeptide, and somatostatin has been observed in whole-mount preparations of rat mesentery by an immunofluorescent double-staining procedure. Peptidergic fibres have been shown either to run in close proximity or come in direct contact with mast cells. This supports earlier morphological and immunohistochemical results suggesting an innervation of mast cells and provides a structural foundation for a series of pharmacological studies which outline the influence of various neuropeptides on mast cell secretory activity.

In an earlier series of studies on cellular labeling with [14C]adenine ([14C]A) in adult rats. Osogoe and his colleagues demonstrated the occurrence of certain cell types which are capable of incorporating [14C]A to a particularly great extent, such as the immature forms of either macrophage or fibroblast or reticulum cell lines. Further investigations have revealed that, among such cell types, a few fibroblastoid cells in the interstitium of the kidney and lung, as well as the proliferative reticulum cells in the intestinal lamina propria, express Ia antigen. In the present study, the reticulum cells in the lymphoid tissues and an appreciable number of mesenchymal cells in the interstitium of the heart and liver were also found to express Ia antigen. These two types of Ia-positive cells were characterized by a large cell body having a large euchromatic nucleus and abundant cytoplasm with dendritic processes. However, the mesenchymal cells were found in the interstitial tissue space of the organs, mostly scattered singly or occasionally grouped in small cell aggregations, without coexisting lymphoid cells. The biological significance of the Ia antigen expression by the two cell types, in particular the mesenchymal cells, is discussed in relation to their capacity for uptake of [14C]A.

The morphological and biochemical characteristics of pigment accumulations found in the kidney, liver, spleen, and mesentery of three different species of teleost fishes have been studied. There are significant differences in number, distribution, and morphology of pigment accumulations in different organs of the three species. Biochemical studies have shown the existence of tyrosinase activity in the mesentery of Mugil cephalus and in the kidney and mesentery of Sparus auratus. No tyrosinase activity was found in any internal organs of Dicertranchus labrax. That activity was assayed using three methods: tyrosine hidroxylation, dopa oxidation, and melanin formation. The morphological and biochemical observations are in agreement. In those organs in which we have demonstrated melanin synthetic activity, the pigment cells are morphologically and like melanophores, while in the organs that show no melanin synthetic activity, the pigment cells resemble macrophages.