Adipose Tissue-Derived Mesenchymal Stem Cells Facilitate Hematopoiesis in Vitro and in Vivo : Advantages Over Bone Marrow-Derived Mesenchymal Stem Cells

Mesenchymal stem cells (MSCs) have emerged as a new therapeutic modality for reconstituting the hematopoietic microenvironment by improving engraftment in stem cell transplantation. However, the availability of conventional bone marrow (BM)-derived MSCs (BMSCs) is limited. Recent studies showed that a large number of MSCs can be easily isolated from fat tissue (adipose tissue-derived MSCs [ADSCs]). In this study, we extensively evaluated the hematopoiesis-supporting properties of ADSCs, which are largely unknown. In vitro coculture and progenitor assays showed that ADSCs generated significantly more granulocytes and progenitor cells from human hematopoietic stem cells (HSCs) than BMSCs. We found that ADSCs express the chemokine CXCL12, a critical regulator of hematopoiesis, at levels that are three fold higher than those with BMSCs. The addition of a CXCL12 receptor antagonist resulted in a lower yield of granulocytes from ADSC layers, whereas the addition of recombinant CXCL12 to BMSC cocultures promoted the growth of granulocytes. In vivo cell homing assays showed that ADSCs facilitated the homing of mouse HSCs to the BM better than BMSCs. ADSCs injected into the BM cavity of fatally irradiated mice reconstituted hematopoiesis more promptly than BMSCs and subsequently rescued mice that had received a low number of HSCs. Secondary transplantation experiments showed that ADSCs exerted favorable effects on long-term HSCs. These results suggest that ADSCs can be a promising therapeutic alternative to BMSCs.Hematopoiesis is a dynamic process that involves self-renewal of hematopoietic stem cells in the bone marrow, generation of lineage-committed cells, and mobilization of mature cells into the bloodstream. Mesenchymal stem cells (MSCs) present in bone marrow (BM) are thought to give rise to cells that constitute the hematopoietic microenvironment. MSCs produce a number of cytokines and extracellular matrix proteins and express cell adhesion molecules, all of which are involved in the regulation of hematopoiesis.¹ Human MSCs, when injected into the bone marrow cavity of nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice, differentiate into pericytes, myofibroblasts, BM stromal cells, bone osteocytes, bone-lining osteoblasts, and endothelial cells, which constitute the functional components of the hematopoietic microenvironment.² In recent studies, cotransplantation of human MSCs and HSCs resulted in increased chimerism or accelerated hematopoietic recovery (or both) in animal models and in humans.^3,4,5,6All of the above studies used bone marrow-derived MSCs (BMSCs). However, there are several drawbacks in the use of BMSCs for clinical application, including the fact that they are only available in limited number even though large quantities of infused cells are required for treatment. In addition, there is a possibility that BMSCs might be contaminated with malignant cells when they are harvested from patients with a hematological malignancy (eg, leukemia). The discoveries that a large number of nonadipocyte stem cells exist in fat tissue (adipose tissue-derived MSCs [ADSCs]) and that these cells can be rapidly expanded ex vivo, suggested that ADSCs might be useful for clinical applications.⁷ Recent studies showed that ADSCs are a viable alternative to BMSCs for treatment of animal models of various kinds of diseases.^8,9,10,11,12 However, it has been reported that even though ADSCs and BMSCs are very similar, ADSCs are not completely identical to BMSCs.^13,14 To date, little is known concerning the ability of ADSCs to support hematopoiesis. We therefore extensively examined the hematopoiesis-supporting properties of ADSCs in vitro and in vivo and report that ADSCs possess several advantages over BMSCs.     

Effects of CO2 laser debonding of a ceramic bracket on the mechanical properties of enamel

Objective:To investigate the effects of CO₂ laser debonding of a ceramic bracket on the mechanical properties of tooth enamel.Materials and Methods:Fifty-three human premolars were used in this study. The temperature changes of cross-sectioned specimens during laser irradiation were monitored with an infrared thermographic microscope system. Different laser output settings (3, 4, 5, and 6 W) were compared. The shear bond strength of brackets after laser irradiation was measured for specimens bonded with a conventional etch and rinse adhesive or with a self-etching adhesive, and the adhesive remnant index score was calculated. The hardness and elastic modulus of cross-sectioned enamel after laser irradiation were investigated by the nanoindentation test. Data were compared by one-way and two-way analysis of variance, followed by the Scheffé test.Results:The temperature of enamel increased by about 200°C under CO₂ laser irradiation with a relatively high output (5 and 6 W), and a temperature increase of about 100°C to 150°C was seen under laser irradiation with a low output (3 and 4 W). The bracket shear bond strength decreased under all laser irradiation conditions. The hardness and elastic modulus of enamel were not affected by CO₂ laser debonding.Conclusion:CO₂ laser debonding may not cause iatrogenic damage to enamel.     

Percutaneous drainage for suppurative pylethrombophlebitis developing in a patient with chronic pancreatitis

Suppurative pylethrombophlebitis is an extremely rare disease with high mortality. It is difficult to diagnose this disease because its nonspecific clinical features are unfamiliar to physicians. A 64-year-old Asian man, who had undergone a longitudinal pancreaticojejunostomy for alcoholic chronic pancreatitis 7 years before, had right upper abdominal pain and high fever. Abdominal sonography and contrast-enhanced abdominal computed tomography detected thrombus and fluid collection in the portal vein. After a percutaneous needle puncture, the patient was diagnosed as having suppurative pylethrombophlebitis and treated with only drainage and antibiotics; no operation was required. This case suggests that minimally invasive percutaneous needle puncture of the intrahepatic portal vein may be an accurate procedure for the appropriate diagnosis and treatment of suppurative pylethrombophlebitis.     

The possible mechanism of enhanced carcinogenesis induced by genotoxic carcinogens in rasH2 mice

Microarray and RT-PCR analyses were performed for the transgene and Ras-related genes in forestomach squamous cell carcinomas (SCCs) induced by 7,12-dimethylbenz[a]anthracene (DMBA) in rasH2 mice; these results were compared with our previous molecular data of N-ethyl-N-nitrosourea-induced forestomach SCCs and urethane-induced lung adenomas in rasH2 mice. Overexpression of the transgene was detected in the DMBA-induced SCCs, suggesting that the transgene plays an important role in enhanced carcinogenesis in rasH2 mice. In addition, the mouse endogenous ras genes were up-regulated in the DMBA-induced SCCs, and are probably involved in the tumorigenesis of forestomach SCCs. Genes such as osteopontin, Cks1b, Tpm1, Reck, gelsolin, and amphiregulin that were commonly altered in these three different carcinogen-induced tumors may contribute to the development of tumors in rasH2 mice.     

Wear characteristics and inhibition of enamel demineralization by resin‐based coating materials

In this study, wear and inhibition of enamel demineralization by resin‐based coating materials were investigated. Seven commercially available coating materials, with and without fillers, were used. A mechanical wear test was performed, and the specimens were then examined with a scanning electron microscope. Hardness and elastic modulus measurements for each material were obtained by nanoindentation testing. Thin layers of each material were applied on human enamel surfaces, which were subjected to alternating immersion in demineralizing and remineralizing solutions. The inhibition ability of enamel demineralization adjacent to the coating was estimated with depth‐dependent mechanical properties using the nanoindentation test. The non‐filled coating material showed significantly lower hardness, lower elastic modulus, and higher weight loss. There were no significant differences in weight loss among the six filled coating materials. After the alternating immersion protocol, the enamel specimens having application of coating materials with ion‐releasing ability were harder than those in the other groups in some locations 1–11 μm from the enamel surface and within 300 μm from the edge of the coating materials. In conclusion, clinical use of the resin‐based coating materials with ion‐releasing ability may prevent demineralization of exposed enamel adjacent to the coating during treatment.     

Endoscopic sonography in the diagnosis of xanthogranulomatous cholecystitis.

Xanthogranulomatous cholecystitis (XGC) is an unusual inflammatory disease of the gallbladder that may simulate gallbladder cancer. We report the findings with conventional sonography, endoscopic sonography (EUS), and CT in 3 cases of XGC. EUS could visualize hyperechoic nodules in the gallbladder wall, probably representing xanthogranulomas, but loss of the multilayered structure of the gallbladder wall and infiltration into adjacent organs make differentiating XGC from gallbladder cancer difficult with EUS alone.     

The outcome of surgical treatment for elderly patients with gastric carcinoma

Background

The aim of this study was to clarify the operative mortality and long‐term survival of gastrectomy for elderly patients with gastric cancer.

Methods

A total of 461 patients who underwent gastrectomy for gastric cancer in our hospital were classified as elderly group (≥80 years‐old, 95 patients) and control group (60–69 years‐old, 366 patients).

Results

The frequency of comorbidities was significantly (P < 0.05) higher in elderly group (74.7%) than that in the control group (49.5%). No significant difference of the postoperative complication rate was found between the elderly group (23.2%) and the control group (23.2%). Adjuvant chemotherapy was 9.5% in the elderly group, which was significantly less than 29.0% of the control group (P < 0.05). Stage II and III elderly patients had worse disease specific survival (DSS) than controls did. In the elderly, overall survival (OS) was significantly worse than DSS in stage I patients (P < 0.05).

Conclusions

The operative complication rate of elderly patients was comparable to the control group. Comorbidity and occurrence of secondary malignant disease should be followed for elderly patients at stage I. For stage II and III disease patients, a novel drug which is acceptable for the elderly is needed as a postoperative therapy. J. Surg. Oncol. 2015 111:848–854. © 2015 The Authors. Journal of Surgical Oncology Published by Wiley Periodicals, Inc.     

Analysis of the IgG Immune Response to Treponema phagedenis-Like Spirochetes in Individual Dairy Cattle with Papillomatous Digital Dermatitis

Papillomatous digital dermatitis (PDD) is a major infectious disease of the foot skin in dairy cattle. Treponema phagedenis-like spirochetes have been consistently detected in PDD lesions, and antibodies against these organisms have been demonstrated in affected cattle. However, little is known about the dominant antigens recognized by the immune system of affected cattle. Here, we investigated the IgG immune response to T. phagedenis-like isolates by Western blotting with different sera using whole-cell lysates and extracted glycolipid from 18 and 8 isolates, respectively, including those from different cattle on the same or different farms, isolates from different lesions affecting a single cow, and different isolates from the same lesion affecting a single cow. The reactivity of sera in Western blot assays revealed different banding patterns or showed no bands, suggesting that considerable antigenic variations, including glycolipid, may exist among the isolates, even in those from single individuals. With use of a total of 151 serum samples collected from three groups of cattle, i.e., PDD-positive cows on PDD-positive farms (group A), PDD-negative cows on PDD-positive farms (group B), and cows on PDD-free farms (group C), the levels of IgG antibodies against four T. phagedenis-like isolates were measured by enzyme-linked immunosorbent assay (ELISA). The optical density in groups A and B was significantly higher than that in group C, even though the value varied among the antigens used. Therefore, combinations of multiple Treponema species should be used for serological analysis and the development of a suitable vaccine because of antigenic variations.Papillomatous digital dermatitis (PDD) is an important leading cause of severe epidemic lameness in dairy cows (18), with resulting economic losses due to decreases in milk production and reproductive performance and the costs of treatment (10, 15, 27).Interestingly, among bacteria in the lesions, a large number of spirochetes have been consistently detected, and these have been identified as Treponema species which are closely related to Treponema phagedenis, which is an inhabitant of the human genital tract, and human oral treponemes, including T. denticola, T. vincentii, and T. medium (2, 7, 12). Their presence in both superficial lesions and deeper layers of the epidermis implies that they may be one of the most predominant populations in the lesions and play a role in the pathogenesis of PDD (12, 17, 19).Humoral and cell-mediated immune responses to T. phagedenis-like spirochetes have been demonstrated in cattle with PDD (4, 5, 6, 29, 30, 31). It has been reported that the levels of antibodies against treponemes in PDD-positive cattle were significantly higher than those in PDD-negative cattle (4, 30, 31). However, little is known about the dominant antigens recognized by the immune system of affected individual cattle. Because no culture methods for isolating treponemes from PDD lesions have been established, there has been a paucity of antigenic and serological analyses using sufficient numbers of isolates.Recently, for the first time in Japan, we successfully isolated 40 spirochete isolates from dairy cattle with PDD lesions by using a simple two-step culture technique, and these isolates were identified as Treponema phagedenis-like spirochetes on the basis of their biochemical traits and enzyme activities, which were identical to those of T. phagedenis ATCC 27087, and the results of sequencing of the 16S rRNA gene showing that all isolates had >99% identity to those of the T. phagedenis type strain and T. phagedenis-like spirochetes isolated from PDD lesions in the United States and Europe (33). Interestingly, considerable genetic diversity was detected among the isolates, not only from different cattle but also from the same individuals, using pulsed-field gel electrophoresis and PCR-based random amplified polymorphism DNA methods (33). Such genetic diversity may underlie the antigenic diversity of these spirochetes, and determination of the bacterial antigens recognized by infected cattle would be useful for the development of a suitable vaccine.In the present study, we investigated the serological characteristics of individual cattle with PDD from which T. phagedenis-like spirochetes were isolated and searched for the main bacterial antigens recognized by affected cattle by using Western blot analysis. Furthermore, we evaluated the potential of the enzyme-linked immunosorbent assay (ELISA) for detecting differences in the IgG antibody response against T. phagedenis-like spirochetes.     

A novel bisphosphonate minodronate (YM529) specifically inhibits osteolytic bone metastasis produced by human small-cell lung cancer cells in NK-cell depleted SCID mice

In the present study, we examined the effects of a newly developed bisphosphonate, minodronate (YM529), on osteolytic bone metastasis caused by lung cancer. Human small-cell lung cancer (SBC-5) cells, injected intravenously into natural killer cell-depleted SCID mice, produced radiologically detectable bone metastasis by day 18 and macroscopically visible visceral metastases (lung, liver, kidney, systemic lymph node) by day 35. Prophylactic treatment with YM529 on day 1 significantly inhibited the formation of osteolytic bone metastasis evaluated on X-ray photographs in a dose-dependent manner. In addition, treatment with YM529 after establishment of bone metastasis (on day 21) also inhibited bone metastasis, although the treatment was more effective when started earlier. Single administration was as effective as repeated treatment, suggesting a sustained inhibitory effect of YM529 on bone metastasis. YM529 reduced the number of osteoclasts in the bone metastatic lesions in vivo, but had no effect on the proliferation or cytokine production of SBC-5 cells in vitro. These results suggest that YM529 is a potent inhibitor of bone metastasis of human lung cancer, probably by suppressing osteoclastic bone resorption. In contrast, treatment with YM529 had no effect on visceral metastasis, even if started on day 1, and did not prolong the survival of the mice. Therefore, development of a combined modality is necessary for prolonging the survival of small-cell lung cancer patients with multiple-organ metastasis. This revised version was published online in July 2006 with corrections to the Cover Date.     

Sigmoid colon cancer presenting as complete rectal prolapse: Report of a case

We describe herein the unusual case of a 76-year-old woman who was diagnosed as having sigmoid colon cancer after presenting with complete rectal prolapse. The rectal prolapse was considered to have been caused by constipation accelerated by the colon cancer. The relationship between colorectal cancer and rectal prolapse has not yet been clarified; however, this case report suggests that rectal prolapse can present as a symptom of colorectal cancer. Thus, patients with a sudden onset of rectal prolapse should be screened for colorectal cancer.