Adipose tissues differentiated by adipose-derived stem cells harvested from transgenic mice

Objective: To induce adipocyte differentiation in vitro by adipose-derived stromal cells (ASCs) harvested from transgenic mice with green fluorescent protein (GFP) and assess the possibility of constructing adipose tissues via attachment of ASCs to typeⅡcollagen scaffolds. Methods: Inguinal fat pads from GFP transgenic mice were digested by enzymes for isolation of ASCs (primary culture). After expansion to three passages of ASCs, the cells were incubated in an adipogenic medium for two weeks, and the adipocyte differentiation by ASCs in vitro was assessed by morphological observation and Oil Red O staining. Then they were attached to collagen scaffolds and co-cultured for 12 hours, followed by hypodermic implantation to the dorsal skin of nude mice for 2 months. The newly-formed tissues were detected by HE staining. Results: The cultured primary stem cells were fibroblast-like and showed active proliferation. After being incubated in an adipocyte differentiation medium, the lipid droplets in the cytoplasm accumulated gradually and finally developed into mature adipocytes, which showed positive in Oil Red O staining. A 0. 5-cm3 new tissue clot was found under the dorsal skin of the nude mice and it was confirmed as mature adipose tissues by fluorescent observation and HE staining. Conclusions: ASCs can successfully differentiate adipose tissues into mature adipocytes, which exhibit an adipocyte-like morphology and express as intracytoplasmic lipid droplets. It is an efficient model of adipose tissues engineered with ASCs and type I collagen scaffolds.     

Pheophytin a, a low molecular weight compound found in the marine brown alga Sargassum fulvellum, promotes the differentiation of PC12 cells

We identified and characterized a neurodifferentiation compound from the marine brown alga Sargassum fulvellum collected from the Japanese coastline. Several instrumental analyses revealed the compound to be pheophytin a. Pheophytin a did not itself promote neurite outgrowth of PC12 cells. However, when PC12 cells were treated with a low concentration of pheophytin a (3.9 microg/ml) in the presence of a low level of nerve growth factor (10 ng/ml), the compound produced neurite outgrowth similar to that produced by a high level of nerve growth factor (50 ng/ml). Pheophytin a also enhanced signal transduction in the mitogen-activated protein kinase signaling pathway, which is also induced by nerve growth factor. The effect of pheophytin a on neurite outgrowth of PC12 cells was completely blocked by U0126, a representative mitogen-activated protein kinase kinase inhibitor. These results suggest that pheophytin a enhances the neurodifferentiation of PC12 cells in the presence of a low level of nerve growth factor and that this effect is mediated by activation of a mitogen-activated protein kinase signaling pathway.     

Allogeneic cell stimulation enhances cytomegalovirus replication in the early period of primary infection in an experimental rat model.

BACKGROUND: Cytomegalovirus (CMV) diseases commonly occur in allograft recipients in the early post-transplant period. However, factors responsible for the high incidence of CMV diseases during this period are not yet fully defined. METHODS: Wistar-Furth (WF; RT-1(u)) rats were inoculated with 10(4) plaque-forming units (PFU) of rat CMV (RCMV) intraperitoneally, and then transplanted with allogeneic lungs from Dark Agouti (DA; RT-1avl) rats or stimulated with 10(7) mitomycin C-treated spleen cells from DA rats by daily sub-cutaneous injections for 2 weeks. No immunosuppressive agent was used. Naive WF rats and WF rats grafted with syngeneic lungs or cells were used as controls. The level of RCMV replication in rats was assessed by infectious virus titers in tissues. RESULTS: The virus titers in salivary glands of allogeneic and syngeneic lung graft recipients were significantly higher than in naive WF rats. The level of RCMV replication in rats stimulated with allogeneic spleen cells was significantly higher than in the syngeneic recipient rats: virus titers in the salivary gland of allogeneic and syngeneic recipients reached 4.61 +/- 0.33 and 4.00 +/- 0.37 log(10) PFU/g tissue, respectively, at 14 days post-infection (p = 0.015). The augmented viral replication in allogeneic recipients was confirmed by an increase in the number of RCMV antigen-positive macrophages present in tissue sections of the salivary gland. CONCLUSIONS: Acute lung allograft rejection and allogeneic spleen cell stimulation enhance CMV replication in the salivary gland of rats. Various responses to allogeneic antigens occurring in the process of acute allograft rejection could be risk factors for post-transplant CMV replication and infection.     

Large Ulcerated Perianal Hidradenoma Papilliferum in a Young Female

BACKGROUND: Hidradenoma papilliferum is an uncommon benign tumor that is located almost exclusively in the vulvar and anal areas. It is usually very small and asymptomatic, and to make a correct diagnosis is clinically very difficult. Occasionally the tumor becomes elevated to form a reddish brown papillary mass, and the surface ulcerates, which may erroneously suggest malignancy. OBJECTIVE: We report a case of a large, perianal hidradenoma papilliferum with suspected malignancy in a young Japanese female. RESULTS: A 22-year-old female had been aware of a perianal nodule for approximately 1 year. Examination of the perianal area revealed a wide pedunculated, reddish nodule with several white maculae. It was ulcerated and bleeding, 2.0 x 1.2 x 0.8 cm in size, and located in the 3 o'clock position. The nodule was totally excised with a narrow margin. The histopathologic diagnosis was hidradenoma papilliferum. No recurrence was observed for 23 months. CONCLUSION: When dermatologists encounter tumors of the anogenital area of adult females, it is important to keep hidradenoma papilliferum in mind as the differential diagnosis. Dermatologists should recognize that the tumor is benign, eliminating the need for wide resection.     

Spontaneous mesenteric hemorrhage associated with ehlers-danlos syndrome

The vascular type of Ehlers-Danlos syndrome is a genetic disorder of connective tissue and is frequently associated with catastrophic arterial complications. Its surgical treatment is extremely difficult because of the fragility of vessels. This article describes three patients with vascular type of Ehlers-Danlos syndrome who developed mesenteric hemorrhage due to spontaneous arterial rupture. The clinical and molecular characteristics of the disease are briefly reviewed.     

Tumorigenicity study in Syrian hamsters fed areca nut together with nitrite

In order to evaluate the effect of concurrent administrationof areca nut and sodium nitrite, a long-term feeding study wasconducted with 120 Syrian hamsters. The animals were dividedinto four treatment groups, each consisting of 15 males and15 females, and received 2 g/kg diet of sodium nitrite (groupI), 20 g/kg diet of powdered areca nut (group II), 2 g/kg dietof sodium nitrite plus 20 g/kg diet of areca nut (group III)or powdered diet only (group IV) throughout their lifetime.Urine samples from all groups were analysed for N-nitrosonipecoticacid (NNIP), a major urinary metabolite of areca-nut-derivednitrosamines. NNIP was only detected in the urine of hamstersfed nitrite plus areca nut (concentration: 1.9±0.9 ng/mlurine), indicating that areca nut alkaloids underwent in vivonitrosation to form arecanut-specific nitrosamines. The totaltumour response was not significantly elevated in groups IIand III. Hamsters of group III had a markedly, but also insignificantlyhigher frequency of malignant tumours than those of the othergroups, with a statistically significant increase in malignantlymphomas in the males. Although limited by the low number ofanimals per group, these results indicate that exposure to nitritetogether with areca nut constituents appears to enhance therisk of developing malignancies.     

Lack of rapid initiating, promoting or sequential syncarcinogenic effects of di(2-ethylhexyl)phthalate in rat liver carcinogenesis

The effect of prolonged dietary administration of the peroxisomeproliferating plasticizer di(2-ethylhexy1)phthalate (DEHP wasstudied on liver carcinogenesis initiated by N-2- fltuorenylmxhmide(FAA) and with that of the neoplasm-promoter phenobarbital (PB).Also, DEHP was studied as an initiator by giving it in placeof FAA before PB. Male rats were fed FAA for 7 weeks to inducebepatocellular altered foci, and were subsequently given nochemical, 12 000 p.p.m. DEHP or 500 p.p.m. PB for 24 weeks inthe diet. In the rats fed DEHP, substantial hepatomegaly andperoxisome proliferation were induced. No evidence of indudionof hepatacellular altered foci or hepatic neoplasms was foundeither when DEHP was given alone for 24 weeks or for 7 weeksfollowed by PB. Also, DEHP fed for 24 weeks had no promotingeffect on liver altered foci that were induced by FAA and producedlittle or no enhancement of the occurrence of FAA-induced liverneoplasms. In contrast, PB exerted a marked enhancing effecton foci and substantially increased the incidence and multiplicityof liver neoplasms. Thus, the findings demonstrate that DEHPdid not have either a rapid initiating activity, a significantsequential syncarcinogenic activity, or a promoting effect onliver carcinogenesis under conditions in which numerous agentswith such activities have been identified.     

Chronic effects of imipramine and lithium on 5-HT receptor subtypes in rat frontal cortex, hippocampus and choroid plexus: quantitative receptor autoradiographic analysis

The effects of chronic treatment with imipramine or lithium on serotonin (5-HT) receptor subtypes were analyzed in the frontal cortex, hippocampus and choroid plexus of rat brain by quantitative receptor autoradiographic procedures, using radioligands [3H]-5-HT, [3H]-8-hydroxy-2-(di-n-propylamino)tetralin ([3H]-8-OH-DPAT), [125I]-iodocyanopindolol ([125I]-CYP), [3H]-mesulergine and [125I]-7-amino-8-iodo-ketanserin ([125I]-ketanserin) or [3H]-spiperone. Chronic i.p. administration of imipramine (20 mg/kg/day for 21 days) decreased the densities of 5-HT1, 5-HT1A, 5-HT1C and 5-HT2 sites in the frontal cortex, hippocampus and choroid plexus. Lithium (2 mEq/kg/day for 21 days) also decreased the densities of 5-HT1, 5-HT1C and 5-HT2 sites in the frontal cortex, and the densities of those including 5-HT1A sites in the hippocampus and choroid plexus. Imipramine and lithium very markedly decreased the density of 5-HT1C sites in the choroid plexus. We propose that methods employing quantitative receptor autoradiographic analysis can be used to characterize and understand the local effects of these drugs on 5-HT receptor subtypes.     

Dynamic MRI of the gallbladder lesions: Differentiation of benign from malignant

Forty-nine pathologically proven gallbladder lesions were evaluated in 45 patients using dynamic MRI with a spoiled gradient pulse sequence (SPGR), to access the ability of this technique to differentiate benign from malignant gallbladder lesions. The studies were reviewed retrospectively. Signal intensity of the lesions were measured. Twenty-one malignant and 28 benign lesions were classified into three categories: polypoid, diffuse wall thickening, and exophytic. Early and delayed enhancement patterns were evaluated. For the polypoid masses, malignant lesions (n = 9) demonstrated early and prolonged enhancements, whereas benign lesions (n = 14) had early enhancement with subsequent washout (P < .05). For diffuse gallbladder wall thickening, malignant lesions (n = 6) demonstrated early and prolonged enhancement and benign lesions (n = 14) showed relatively slow, prolonged enhancement (P < .05). The exophytic masses (n = 6) all were malignant and demonstrated early and prolonged enhancement. Dynamic MRI can help differentiate benign from malignant gallbladder lesions.     

Electrochemotherapy significantly inhibits the growth of colon 26 tumors in mice

Electrochemotherapy is a novel antitumor treatment involving the systemic administration of bleomycin followed by the delivery of electrical pulses to the tumor. The present study investigates the effects of electrochemotherapy on the growth of colon 26 cells inoculated subcutaneously into the backs of BALB/c mice. The mice were divided into the following four experimental groups: 20 that received no further treatment after the inoculation of colon 26 cells (control group); 20 that received 500 μg of bleomycin intraperitoneally 7 and 9 days after the inoculation (BLM group); 20 that received electric pulses to the tumor 7 and 9 days after the inoculation (EP group); and 30 that received electrochemotherapy 7 and 9 days after the inoculation (ECT group). During 28 days of observation, no deaths due to tumor progression occurred in the ECT group, but there were 18 in the control group, 11 in the BLM group, and 18 in the EP group. While weight loss was observed in all groups, it was most remarkable in the control group. Tumor growth was significantly inhibited in the ECT group, compared to the other experimental groups (P<0.01). The results of this study demonstrated that electrochemotherapy significantly inhibited the growth of colon 26 tumors in mice, without causing any remarkable adverse effects.