The Treatment of Refractory Vitiligo With Autologous Cultured Epithelium Grafting: A Real-World Retrospective Cohort Study

BACKGROUND

Surgical intervention is the main therapy for refractory vitiligo. We developed a modified autologous cultured epithelial grafting (ACEG) technique for vitiligo treatment. Between January 2015 and June 2019, a total of 726 patients with vitiligo underwent ACEG in China, with patient characteristics and clinical factors being meticulously documented. Using a generalized linear mixed model, we were able to assess the association between these characteristics and the repigmentation rate.

RESULTS

ACEG demonstrated a total efficacy rate of 82.81% (1754/2118) in treating 726 patients, with a higher repigmentation rate of 64.87% compared to conventional surgery at 52.69%. Notably, ACEG showed a better response in treating segmental vitiligo, lesions on lower limbs, age ≤ 18, and stable period > 3 years. A keratinocyte:melanocyte ratio below 25 was found to be advantageous too. Single-cell RNA sequencing analysis revealed an increase in melanocyte count and 2 subclusters of keratinocytes after ACEG, which remained higher in repigmented sites even after 1 year.

CONCLUSIONS

ACEG is a promising therapy for refractory vitiligo. Patient age, clinical type, lesion site, and stability before surgery influence repigmentation in ACEG. The mechanism of repigmentation after ACEG treatment is likely not confined to the restoration of melanocyte populations. It may also involve an increase in the number of keratinocytes that support melanocyte function within the affected area. These keratinocytes may aid the post-transplant survival and function of melanocytes by secreting cytokines and extracellular matrix components.

TRIAL REGISTRATION

registered with Chictr.org.cn (ChiCTR2100051405).

Associations among antimicrobial use, calf management practices, and antimicrobial resistance in Escherichia coli from a pooled fecal sample in calves on Canadian dairy farms: a cross-sectional study

The objective of this cross-sectional study was to determine associations between calf management practices, the number of antimicrobial treatments, and antimicrobial resistance in pre-weaned heifers on Canadian dairy farms. A composite of 5 fecal samples from pre-weaned calves was collected from 142 dairy farms in 5 provinces and analyzed for phenotypic antimicrobial susceptibility with the microbroth dilution method. Questionnaires were used to capture herd characteristics and calf management practices used on the farm. Calf treatment records were collected during the farm visits. Escherichia coli was isolated from all 142 fecal samples with the highest resistance to tetracycline (41%), followed by sulfisoxazole (36%), streptomycin (32%), chloramphenicol (28%), ampicillin (16%), trimethoprim-sulfamethoxazole (15%), ceftriaxone (4.2%), cefoxitin (2.8%), amoxicillin-clavulanic acid (2.1%), ciprofloxacin (2.1%), nalidixic acid (2.1%), azithromycin (1.4%), and gentamicin (1.4%). Multidrug resistance was observed in 37% of E. coli isolates. Three-quarters of farms used fresh colostrum as the most common type of colostrum fed to calves. Colostrum quality was checked on 49% of farms, but the transfer of passive immunity was only checked on 32% of farms in the last 12 mo. Almost 70% of farms used straw or hay or a combination as the bedding material for calves. Among the 142 farms, a complete set of calf records were collected from 71 farms. In a multivariable logistic regression model, farms with ≥1.99 - 32.57 antimicrobial treatments/calf-year were 3.2 times more likely to have multidrug resistant E. coli in calf feces compared farms with <1.99 antimicrobial treatments/calf-year. Farms using hay or straw beddings were 5.1 times less likely to have multidrug resistant E. coli compared with those with other bedding materials including shavings or sawdust. Bedding management practices on farms may need to be investigated to reduce the potential impact on disseminating multidrug resistant bacteria.

Associations of calf management practices with antimicrobial use in Canadian dairy calves

The objective of this cross-sectional study was to investigate the relationship between management practices and antimicrobial use in heifer calves on Canadian dairy farms. Questionnaires on calf management practices, herd characteristics, and calf treatment records were administered on 147 dairy farms in 5 provinces during annual farm visits in a multiyear, nationwide research project (Canadian Dairy Network for Antimicrobial Stewardship and Resistance: CaDNetASR). Questions focused on the calf caregiver, calving pen, colostrum management, milk feeding, grouping, bedding management, and age when male calves were sold. Antimicrobial treatment records were collected on each farm from either an electronic herd management system or paper-based records. Newborn heifers born in the last 12 mo were identified retrospectively and followed to 60 d of age, with antimicrobial treatments and dates of sale or death extracted for further analysis. A multivariable linear regression model was developed with the natural log of the number of antimicrobial treatments per calf-year as the dependent variable, and categorized calf management practices and farm characteristics as the independent variables. A complete data set of records on 7,817 calves was retrieved from 74 farms based on completeness of calf records. A total of 2,310 calves were treated at least once with an antimicrobial, and 7,307 individual antimicrobial treatments were recorded. Among the reasons for antimicrobial use, respiratory disease (54%) was most common, followed by diarrhea (20%), presence of a fever (3%), and umbilical disease (2%). Florfenicol (33% of recorded treatments), penicillin (23%), and trimethoprim-sulfamethoxazole (18%) were commonly used, whereas fluoroquinolones (4%), and ceftiofur (1%) were used less commonly. Farms (31%) commonly had 0-1.0 antimicrobial treatments/calf-year (median: 2.2 treatments/calf-year; interquartile range: 0.64-6.43 treatments/calf-year). Defined daily dose (DDD) per calf-year was calculated based on the Canadian bovine standards. Among the 74 farms, florfenicol (1.35 DDD/calf-year) and macrolides (0.73 DDD/calf-year) were used most, whereas ceftiofur (0.008 DDD/calf-year) was the lowest. The final multivariable linear regression model indicated that farms that fed transition milk had fewer than half the number of antimicrobial treatments per calf-year than those who did not feed transition milk. The number of antimicrobial treatments per calf-year in preweaning calves was low on many farms, and there was low use of highly important drugs for human medicine. The effect of feeding transition milk should be investigated regarding potential effects on antimicrobial use and disease prevention.

Colostrum management practices that improve the transfer of passive immunity in neonatal dairy calves: A scoping review

The objective of this scoping review was to describe the literature on the characteristics and management practices of colostrum feeding and their associations with the level of transfer of passive immunity (TPI) in dairy calves. Observational and experimental studies were searched in 5 electronic databases and 3 conference proceedings. Two reviewers independently screened primary studies, either analytic observational or experimental studies written in English. Studies on dairy or dual-purpose calves with passive immunity analyzed by blood sampling between 1 to 9 days of age were included. All studies had to compare at least one colostrum intervention or risk factor and their association with passive immunity. Of the 3,675 initially identified studies, 256 were included in this synthesis. One hundred and ninety-five were controlled trials, 57 were cohort studies, and 4 were cross-sectional studies. The effect of colostral quantity at first feeding was investigated in 30 controlled studies including studies that were comparable to each other. The effect of colostral quality was explored in 24 controlled studies with inconsistent criteria used to define the quality. The effect of the timing of first feeding of colostrum was investigated in 21 controlled studies, where the timing of feeding ranged widely from immediately after birth to 60 h of age. Only 4 controlled studies evaluated the relationship between bacterial load in the colostrum and TPI in dairy calves. Of the 256 total studies, 222 assessed blood IgG concentration while 107 measured blood total protein concentration. We identified a gap in knowledge on the association between passive immunity in dairy calves and the bacterial load in colostrum, or the timing of harvesting colostrum from the dam. A possible quantitative synthesis could be conducted among the studies that evaluated colostral quantity at the first feeding in relation to TPI in dairy calves.

Characterizing the literature surrounding transportation of young dairy calves: A scoping review

Transportation is a stressful event for cattle, as it may involve various handling practices, commingling, deprivation of food and water, and fluctuating temperatures. Calves are particularly susceptible to these stressors because their physiological and immune systems are still developing. There has been no formal synthesis of the scientific literature evaluating the effect of transportation on young dairy calf health and performance; the aim of this scoping review is to describe and characterize this body of work. We targeted both descriptive and analytic studies examining transport of calves, including listing how the effect of transport has been evaluated. Eight databases were searched for relevant articles with eligible studies being primary research articles investigating transportation of calves of either sex who were younger than 60 d of age or weighed less than 100 kg. Two reviewers independently screened the title and abstracts of 6,859 articles with 361 potentially relevant articles screened at full text. Of these, 46 were relevant and had data extracted. Articles reporting study location were conducted in the United States (n = 5), Australia (n = 3), Japan (n = 3), and New Zealand (n = 3). Common transport-related variables evaluated included time in transit (n = 13), distance of transportation (n = 8), vehicle-related factors (n = 8), and age at time of transportation (n = 4). Outcome measures varied greatly, including blood parameters (n = 28), health assessments (n = 20), weight (n = 17), behavioral metrics (n = 14), mortality (n = 7), feed intake following transportation (n = 4), salivary cortisol concentrations (n = 3), morbidity (n = 3), and isolation of Salmonella Dublin in fecal samples (n = 2). Outcome parameters were measured during transport or ranged from immediately after to one year following transportation. As the transport-related risk factors and outcomes measured assessed varied widely between studies, future quantitative synthesis (e.g., meta-analysis) in this area may be limited. Several knowledge gaps were identified, including methods to prepare calves for transportation, such as improving nutrition, administering medication, or transporting calves at an older age or weight. Further research could also focus on consistent and clear reporting of key items related to study conduct and analysis, as well as the development of a core outcome set for calf transport studies.

Glucose-6-Phosphate Dehydrogenase in the Pentose Phosphate Pathway Is Localized in Vanadocytes of the Vanadium-Rich Ascidian, Ascidia sydneiensis samea

Ascidians are sessile marine animals known to accumulate high levels of vanadium selectively in vanadium-containing blood cells (vanadocytes). Almost all the vanadium accumulated in the vacuoles of vanadocytes is reduced to the +3 oxidation state via the +4 oxidation state, although vanadium is dissolved in the +5 oxidation state in sea water. Some of the reducing agents that participate in the reduction have been proposed. By chemical study, vanadium in the +5 oxidation state was reported to be reduced to the +4 oxidation state in the presence of NADPH. The present study revealed the existence of glucose-6-phosphodehydrogenase (G6PDH), the first enzyme to produce NADPH in the pentose phosphate pathway, in vanadocytes of a vanadium-rich ascidian. The results suggested that G6PDH conjugates the reduction of vanadium from the +5 through to the +4 oxidation state in vanadocytes of ascidians.

High resolution, low hν photoelectron spectroscopy with the use of a microwave excited rare gas lamp and ionic crystal filters

The need for not only bulk sensitive but also extremely high resolution photoelectron spectroscopy for studying detailed electronic structures of strongly correlated electron systems is growing rapidly. Moreover, easy access to such a capability in one's own laboratory is desirable. Demonstrated here is the performance of a microwave excited rare gas (Xe, Kr, and Ar) lamp combined with ionic crystal filters (sapphire, CaF(2), and LiF), which can supply three strong lines near the photon energy of hnyu hν=8.4, 10.0, and 11.6 eV, with the hν resolution of better than 600 μeV for photoelectron spectroscopy. Its performance is demonstrated on some materials by means of both angle-integrated and angle-resolved measurements.

Mesenchymal to embryonic incomplete transition of human cells by chimeric OCT4/3 (POU5F1) with physiological co-activator EWS

POU5F1 (more commonly known as OCT4/3) is one of the stem cell markers, and affects direction of differentiation in embryonic stem cells. To investigate whether cells of mesenchymal origin acquire embryonic phenotypes, we generated human cells of mesodermal origin with overexpression of the chimeric OCT4/3 gene with physiological co-activator EWS (product of the EWSR1 gene), which is driven by the potent EWS promoter by translocation. The cells expressed embryonic stem cell genes such as NANOG, lost mesenchymal phenotypes, and exhibited embryonal stem cell-like alveolar structures when implanted into the subcutaneous tissue of immunodeficient mice. Hierarchical analysis by microchip analysis and cell surface analysis revealed that the cells are subcategorized into the group of human embryonic stem cells and embryonal carcinoma cells. These results imply that cells of mesenchymal origin can be traced back to cells of embryonic phenotype by the OCT4/3 gene in collaboration with the potent cis-regulatory element and the fused co-activator. The cells generated in this study with overexpression of chimeric OCT4/3 provide us with insight into cell plasticity involving OCT4/3 that is essential for embryonic cell maintenance, and the complexity required for changing cellular identity.

Novel cardiac precursor-like cells from human menstrual blood-derived mesenchymal cells

Stem cell therapy can help repair damaged heart tissue. Yet many of the suitable cells currently identified for human use are difficult to obtain and involve invasive procedures. In our search for novel stem cells with a higher cardiomyogenic potential than those available from bone marrow, we discovered that potent cardiac precursor-like cells can be harvested from human menstrual blood. This represents a new, noninvasive, and potent source of cardiac stem cell therapeutic material. We demonstrate that menstrual blood-derived mesenchymal cells (MMCs) began beating spontaneously after induction, exhibiting cardiomyocyte-specific action potentials. Cardiac troponin-I-positive cardiomyocytes accounted for 27%-32% of the MMCs in vitro. The MMCs proliferated, on average, 28 generations without affecting cardiomyogenic transdifferentiation ability, and expressed mRNA of GATA-4 before cardiomyogenic induction. Hypothesizing that the majority of cardiomyogenic cells in MMCs originated from detached uterine endometrial glands, we established monoclonal endometrial gland-derived mesenchymal cells (EMCs), 76%-97% of which transdifferentiated into cardiac cells in vitro. Both EMCs and MMCs were positive for CD29, CD105 and negative for CD34, CD45. EMCs engrafted onto a recipient's heart using a novel 3-dimensional EMC cell sheet manipulation transdifferentiated into cardiac tissue layer in vivo. Transplanted MMCs also significantly restored impaired cardiac function, decreasing the myocardial infarction (MI) area in the nude rat model, with tissue of MMC-derived cardiomyocytes observed in the MI area in vivo. Thus, MMCs appear to be a potential novel, easily accessible source of material for cardiac stem cell-based therapy.

Hepatic differentiation of human bone marrow-derived UE7T-13 cells: Effects of cytokines and CCN family gene expression

AIM

Bone marrow-derived mesenchymal stem cells (MSC) are expected to be an excellent source of cells for transplantation. We aimed to study the culture conditions and involved genes to differentiate MSC into hepatocytes.

METHODS

The culture conditions to induce the efficient differentiation of human bone marrow-derived UE7T-13 cells were examined using cytokines, hormones, 5-azacytidine and type IV collagen.

RESULTS

We found that combination of acidic fibroblast growth factor (aFGF), basic fibroblast growth factor (bFGF) and hepatocyte growth factor (HGF) with type IV collagen coating induced hepatic differentiation of UE7T-13 cells at over 30% frequency, where expression of albumin mRNA was increased over 20-fold. The differentiated cells had functions of albumin production, glycogen synthesis and urea secretion as well as expressing hepatocyte-specific genes. In addition, these cellshave binuclear and cuboidal morphology, which is a characteristic feature of hepatocytes. During hepatic differentiation, UE7T-13 cells showed depressed expression of WISP1 and WISP2 genes, members of the CCN family. Conversely, knockdown of WISP1 or WISP2 gene by siRNA stimulated hepatic differentiation. The effect of aFGF/bFGF/HGF/type IV collagen coating and WISP1-siRNA on hepatic differentiation was additive.

CONCLUSION

The present study suggests that aFGF/bFGF/HGF/type IV collagen coating is the efficient condition for hepatic differentiation of UE7T-13 cells, and that WISP1 and WISP2 play an important role in hepatic transdifferentiation of these cells.

A role of Wnt/beta-catenin signals in hepatic fate specification of human umbilical cord blood-derived mesenchymal stem cells

Human umbilical cord blood-derived mesenchymal stem cells (UCBMSCs) are expected to be an excellent source of cells for transplantation. In addition, the stem cell plasticity of human UCBMSCs, which can transdifferentiate into hepatocytes, has been reported. However, the mechanisms involved remain to be clarified. To identify the genes and/or signals that are important in specifying the hepatic fate of human UCBMSCs, we analyzed gene expression profiles during the hepatic differentiation of UCBMSCs with human telomerase reverse transcriptase, UCBMSCs immortalized by infection with a retrovirus carrying telomerase reverse transcriptase, but whose differentiation potential remains unchanged. Efficient differentiation was induced by 5-azacytidine (5-aza)/hepatocyte growth factor (HGF)/oncostatin M (OSM)/fibroblast growth factor 2 (FGF2) treatment in terms of function as well as protein expression: 2.5-fold increase in albumin, 4-fold increase in CCAAT enhancer-binding protein alpha, 1.5-fold increase in cytochrome p450 1A1/2, and 8-fold increase in periodic acid-Schiff staining. Consequently, we found that the expression of Wnt/beta-catenin-related genes downregulated, and the translocation of beta-catenin was observed along the cell membrane and in the cytoplasm, although some beta-catenin was still in the nucleus. Downregulation of Wnt/beta-catenin signals in the cells by Fz8-small interference RNA treatment, which was analyzed with a Tcf4 promoter-luciferase assay, resulted in similar hepatic differentiation to that observed with 5-azacytidine/HGF/OSM/FGF2. In addition, the subcellular distribution of beta-catenin was similar to that of cells treated with 5-azacytidine/HGF/OSM/FGF2. In conclusion, the suppression of Wnt/beta-catenin signaling induced the hepatic differentiation of UCBMSCs, suggesting that Wnt/beta-catenin signals play an important role in the hepatic fate specification of human UCBMSCs.

[Recurrence after bullectomy by video-assisted thoracic surgery for spontaneous pneumothorax in younger ages]

We reported 2 cases of recurrent pneumothorax after thoracoscopic bullectomy. The patients are 19-year-old and 21-year-old men. The distensible bullae without macroscopic emphysematous change were found at initial surgery in both patients. They experienced the recurrence at 21 months and 25 months respectively. Interestingly, small bullae along the overall length of the previous stapled line were found in both cases. Histological examination of the resected lungs at the 1st and 2nd operation disclosed microscopic emphysema in the macroscopically normal lung tissue. Pathologic findings suggest that new bullous lesions developed from the microscopic emphysematous lesion around the stapled line. Distortion of lung tissue by stapling is likely to be the cause of new bullous formation. Reinforcement around stapled line covered with absorbable material might be necessary at the initial surgery to prevent recurrence in younger patients.

The significant cardiomyogenic potential of human umbilical cord blood-derived mesenchymal stem cells in vitro

We tested the cardiomyogenic potential of the human umbilical cord blood-derived mesenchymal stem cells (UCBMSCs). Both the number and function of stem cells may be depressed in senile patients with severe coronary risk factors. Therefore, stem cells obtained from such patients may not function well. For this reason, UCBMSCs are potentially a new cell source for stem cell-based therapy, since such cells can be obtained from younger populations and are being routinely utilized for clinical patients. The human UCBMSCs (5 x 10(3) per cm(2)) were cocultured with fetal murine cardiomyocytes ([CM] 1 x 10(5) per cm(2)). On day 5 of cocultivation, approximately half of the green fluorescent protein (GFP)-labeled UCBMSCs contracted rhythmically and synchronously, suggesting the presence of electrical communication between the UCBMSCs. The fractional shortening of the contracted UCBMSCs was 6.5% +/- 0.7% (n = 20). The UCBMSC-derived cardiomyocytes stained positive for cardiac troponin-I (clear striation +) and connexin 43 (diffuse dot-like staining at the margin of the cell) by the immunocytochemical method. Cardiac troponin-I positive cardiomyocytes accounted for 45% +/- 3% of GFP-labeled UCBMSCs. The cardiomyocyte-specific long action potential duration (186 +/- 12 milliseconds) was recorded with a glass microelectrode from the GFP-labeled UCBMSCs. CM were observed in UCBMSCs, which were cocultivated in the same dish with mouse cardiomyocytes separated by a collagen membrane. Cell fusion, therefore, was not a major cause of CM in the UCBMSCs. Approximately half of the human UCBMSCs were successfully transdifferentiated into cardiomyocytes in vitro. UCBMSCs can be a promising cellular source for cardiac stem cell-based therapy. Disclosure of potential conflicts of interest is found at the end of this article.

'Working' cardiomyocytes exhibiting plateau action potentials from human placenta-derived extraembryonic mesodermal cells

The clinical application of cell transplantation for severe heart failure is a promising strategy to improve impaired cardiac function. Recently, an array of cell types, including bone marrow cells, endothelial progenitors, mesenchymal stem cells, resident cardiac stem cells, and embryonic stem cells, have become important candidates for cell sources for cardiac repair. In the present study, we focused on the placenta as a cell source. Cells from the chorionic plate in the fetal portion of the human placenta were obtained after delivery by the primary culture method, and the cells generated in this study had the Y sex chromosome, indicating that the cells were derived from the fetus. The cells potentially expressed 'working' cardiomyocyte-specific genes such as cardiac myosin heavy chain 7beta, atrial myosin light chain, cardiac alpha-actin by gene chip analysis, and Csx/Nkx2.5, GATA4 by RT-PCR, cardiac troponin-I and connexin 43 by immunohistochemistry. These cells were able to differentiate into cardiomyocytes. Cardiac troponin-I and connexin 43 displayed a discontinuous pattern of localization at intercellular contact sites after cardiomyogenic differentiation, suggesting that the chorionic mesoderm contained a large number of cells with cardiomyogenic potential. The cells began spontaneously beating 3 days after co-cultivation with murine fetal cardiomyocytes and the frequency of beating cells reached a maximum on day 10. The contraction of the cardiomyocytes was rhythmical and synchronous, suggesting the presence of electrical communication between the cells. Placenta-derived human fetal cells may be useful for patients who cannot supply bone marrow cells but want to receive stem cell-based cardiac therapy.

Menstrual blood-derived cells confer human dystrophin expression in the murine model of Duchenne muscular dystrophy via cell fusion and myogenic transdifferentiation

Duchenne muscular dystrophy (DMD), the most common lethal genetic disorder in children, is an X-linked recessive muscle disease characterized by the absence of dystrophin at the sarcolemma of muscle fibers. We examined a putative endometrial progenitor obtained from endometrial tissue samples to determine whether these cells repair muscular degeneration in a murine mdx model of DMD. Implanted cells conferred human dystrophin in degenerated muscle of immunodeficient mdx mice. We then examined menstrual blood-derived cells to determine whether primarily cultured nontransformed cells also repair dystrophied muscle. In vivo transfer of menstrual blood-derived cells into dystrophic muscles of immunodeficient mdx mice restored sarcolemmal expression of dystrophin. Labeling of implanted cells with enhanced green fluorescent protein and differential staining of human and murine nuclei suggest that human dystrophin expression is due to cell fusion between host myocytes and implanted cells. In vitro analysis revealed that endometrial progenitor cells and menstrual blood-derived cells can efficiently transdifferentiate into myoblasts/myocytes, fuse to C2C12 murine myoblasts by in vitro coculturing, and start to express dystrophin after fusion. These results demonstrate that the endometrial progenitor cells and menstrual blood-derived cells can transfer dystrophin into dystrophied myocytes through cell fusion and transdifferentiation in vitro and in vivo.

Hyaline cartilage formation and enchondral ossification modeled with KUM5 and OP9 chondroblasts

What is it that defines a bone marrow-derived chondrocyte? We attempted to identify marrow-derived cells with chondrogenic nature and immortality without transformation, defining "immortality" simply as indefinite cell division. KUM5 mesenchymal cells, a marrow stromal cell line, generated hyaline cartilage in vivo and exhibited enchondral ossification at a later stage after implantation. Selection of KUM5 chondroblasts based on the activity of the chondrocyte-specific cis-regulatory element of the collagen alpha2(XI) gene resulted in enhancement of their chondrogenic nature. Gene chip analysis revealed that OP9 cells, another marrow stromal cell line, derived from macrophage colony-stimulating factor-deficient osteopetrotic mice and also known to be niche-constituting cells for hematopoietic stem cells expressed chondrocyte-specific or -associated genes such as type II collagen alpha1, Sox9, and cartilage oligomeric matrix protein at an extremely high level, as did KUM5 cells. After cultured OP9 micromasses exposed to TGF-beta3 and BMP2 were implanted in mice, they produced abundant metachromatic matrix with the toluidine blue stain and formed type II collagen-positive hyaline cartilage within 2 weeks in vivo. Hierarchical clustering and principal component analysis based on microarray data of the expression of cell surface markers and cell-type-specific genes resulted in grouping of KUM5 and OP9 cells into the same subcategory of "chondroblast," that is, a distinct cell type group. We here show that these two cell lines exhibit the unique characteristics of hyaline cartilage formation and enchondral ossification in vitro and in vivo.

Characterization and gene transfer in mesenchymal stem cells derived from human umbilical-cord blood

It has been shown that the stromal-cell population found in bone marrow can be expanded and differentiated into cells with the phenotypes of bone, cartilage, muscle, neural, and fat cells. However, whether mesenchymal stem cells (MSCs) are present in human umbilical-cord blood (UCB) has been the subject of ongoing debate. In this study, we report on a population of fibroblastlike cells derived from the mononuclear fraction of human UCB with osteogenic and adipogenic potential, as well as the presence of a subset of cells that have been maintained in continuous culture for more than 6 months. These cells were found to express CD29, CD44, CD90, CD95, CD105, CD166, and MHC class, but not CD14, CD34, CD40, CD45, CD80, CD86, CD117, CD152, or MHC class II. We also compared gene expression after gene transfer using lenti- and adenoviral vectors carrying the green fluorescence protein to the MSCs derived from UCB because a reliable gene-delivery system is required to transfer target genes into MSCs, which have attracted attention as potential platforms for the systemic delivery of therapeutic genes. The lentiviral vectors can transduce these cells more efficiently than can adenoviral vectors, and we maintained transgene expression for at least 5 weeks. This is the first report showing that UCB-derived MSCs can express exogenous genes by way of a lentivirus vector. These results demonstrate that human UCB is a source of mesenchymal progenitors and may be used in cell transplantation and a wide range of gene-therapy treatments.

Cell separation between mesenchymal progenitor cells through porous polymeric membranes

This study investigates the separation of two types of marrow stromal cells, KUSA-A1 osteoblasts and H-1/A preadipocytes, by filtration through various porous polymeric membranes. It was found that KUSA-A1 permeates better than H-1/A cells through 12-microm polyurethane foaming membranes. This appears to be due to the relatively smaller cell size of KUSA-A1 cells. In addition, when feed solutions containing suspensions of either cell type or a mixture of the two were used, the permeation ratio was relatively low (< 6%) through polyurethane and surface-modified polyurethane foaming membranes. It was also found that there was some degree of separation between KUSA-A1 and H-1/A cells (separation factor = 1.8) with nylon-net filter membranes, but no separation was obtained when filters made of nonwoven fabrics or silk screens were used. This ability of the nylon-net filter membranes to separate the two cell types was due to a sieving effect that results from an optimal pore size. Finally, permeation of a solution of human serum albumin through the membrane following filtration of the cells did not result in a separation of cells in the recovery solution.

Membranous osteogenesis system modeled with KUSA-A1 mature osteoblasts

Several stromal cells were established from murine bone marrow cultures. One of the KUSA subclones, KUSA-A1 cells, displays osteogenic characteristics in vitro and in vivo. The calcium deposition, osteocalcin release, and parathyroid hormone (PTH) responsiveness of KUSA-A1 cells indicate that they are mature osteoblasts or osteocytes. Bone had formed in subcutaneous tissue 1 week after subcutaneous injection of cells into immunodeficient mice. The osteogenesis by KUSA-A1 was not mediated by chondrogenesis and thus was considered to be membranous ossification. These unique characteristics of KUSA-A1 cells provide an opportunity to analyze the process of membranous ossification in detail.

Photon-modulated changes of cell attachments on poly(spiropyran-co-methyl methacrylate) membranes

Spiropyran is a photoresponsive molecule, and nonionic spiropyran is reversibly changed by UV irradiation to a hydrophilic polar, zwitterionic merocyanine isomer, and back again by visible light irradiation. A copolymer of nitrobenzospiropyran and methyl methacrylate, poly(NSP-co-MMA) was used as a material with a photosensitive surface. UV irradiation of the photosensitive surface of poly(NSP-co-MMA)-coated glass plates decreased the water contact angles (11 +/- 1 degrees ) and increased diameter of a water drop relative to the unexposed surface. Light-induced detachment of platelets and mesenchymal stem (KUSA-A1) cells on poly(NSP-co-MMA)-coated glass plates was observed upon simple- and patterned-light irradiation, whereas no light-induced detachment of platelets and mesenchymal stem cells was observed on poly(methyl methacrylate)-coated glass plates. This is a result of the change from a closed nonpolar spiropyran to the polar zwitterionic merocyanine isomer induced by UV irradiation. Light-induced detachment of fibrinogen adsorbed on poly(NSP-co-MMA) coated glass plates was also observed in this investigation.

Immortalization of human fetal cells: the life span of umbilical cord blood-derived cells can be prolonged without manipulating p16INK4a/RB braking pathway

Human umbilical cord blood-derived mesenchymal stem cells (UCBMSCs) are expected to serve as an excellent alternative to bone marrow-derived human mesenchymal stem cells. However, it is difficult to study them because of their limited life span. To overcome this problem, we attempted to produce a strain of UCBMSCs with a long life span and to investigate whether the strain could maintain phenotypes in vitro. UCBMSCs were infected with retrovirus carrying the human telomerase reverse transcriptase (hTERT) to prolong their life span. The UCBMSCs underwent 30 population doublings (PDs) and stopped dividing at PD 37. The UCBMSCs newly established with hTERT (UCBTERTs) proliferated for >120 PDs. The p16INK4a/RB braking pathway leading to senescence can be inhibited by introduction of Bmi-1, a polycomb-group gene, and human papillomavirus type 16 E7, but the extension of the life span of the UCBMSCs with hTERT did not require inhibition of the p16INK4a/RB pathway. The characteristics of the UCBTERTs remained unchanged during the prolongation of life span. UCBTERTs provide a powerful model for further study of cellular senescence and for future application to cell-based therapy by using umbilical cord blood cells.

Self-reversal phenomena of toroidal current by reversing the external toroidal field in helicity-driven toroidal plasmas

In order to understand self-organization in helicity-driven systems, we have investigated the dynamics of low-aspect-ratio toroidal plasmas by decreasing the external toroidal field and reversing its sign in time. Consequently, we have discovered that the helicity-driven toroidal plasma relaxes towards the flipped state. Surprisingly, it has been observed that not only toroidal flux but also poloidal flux reverses sign spontaneously during the relaxation process. The self-reversal of the magnetic fields is attributed to the nonlinear growth of the n=1 kink instability of the central open flux.

Expressed sequence tag analysis of blood cells in the vanadium-rich ascidian, Ascidia sydneiensis samea--a survey of genes for metal accumulation

Some species in the family Ascidiidae accumulate vanadium at concentrations in excess of 350 mM, which corresponds to about 10(7) times that found in seawater. The vanadium ions are stored in vacuoles located within vanadium-containing blood cells, vanadocytes. To investigate the phenomenon, an expressed sequence tag analysis (EST) of a cDNA library of Ascidia sydneiensis samea blood cells was carried out. Three hundred clones were obtained and sequenced by EST analysis. A similarity search revealed that 158 of the clones (52.7%) were known genes, and 142 of the clones (47.3%) did not have any similarity to genes registered in the SwissProt database. According to the functions of their genes the identified EST clones were categorized into eight types of clones; these consisted of genes; metal-related proteins (29 clones), signal transduction (22 clones), protein synthesis (17 clones), nuclear proteins (17 clones), cytoskeleton and motility (14 clones), energy conversion (3 clones), hypothetical proteins (11 clones), and others (45 clones). The ferritin homologue has a high degree of similarity to that of mammals; the iron-binding sites of ferritin are well conserved including His-118 which is important for capturing Fe(2+), also works as a ligand for VO(2+).

Vanadocytes, cells hold the key to resolving the highly selective accumulation and reduction of vanadium in ascidians

Since Henze discovered vanadium in the blood (or coelomic) cells of an ascidian in 1911, this unusual phenomenon has attracted the interest of many investigators. The highest concentration of vanadium (350 mM) in the blood cells of Ascidia gemmata, which belongs to the suborder Phlebobranchia, is 10(7) times higher than that in seawater. Of the approximately 10 types of blood cells, a combination of cell fractionation and neutron-activation analysis revealed that the signet ring cells were the true vanadocytes. In the vanadocytes, 97.6% of the vanadium is in the +3 oxidation state (III). The extremely low pH of 1.9 found in vanadocytes suggests that protons, concentrated by an H(+)-ATPase, might be linked to the accumulation of vanadium energetically. The antigen recognized by a monoclonal antibody, S4D5, prepared to identify vanadocytes, was determined to be 6-PGDH in the pentose phosphate pathway. NADPH produced in the pentose phosphate pathway in vanadocytes is thought to participate in the reduction of vanadium(V) to vanadium(IV). During embryogenesis, a vanadocyte-specific antigen first appears in the body wall at the same time that significant accumulations of vanadium become apparent. Three different vanadium-associated proteins (VAPs) were extracted from the blood cells of vanadium-rich ascidians. These are 12.5, 15, and 16 kDa in size and are associated with vanadium in an approximate ratio of 1:16. The cDNA encoding the 12.5 and 15 kDa VAPs was isolated and the proteins encoded were found to be novel. Further biochemical and biophysical characterization of the VAPs is in progress.

Scanning x-ray microscopy of living and freeze-dried blood cells in two vanadium-rich ascidian species, Phallusia mammillata and Ascidia sydneiensis samea

Some ascidians (sea squirts) accumulate the transitional metal vanadium in their blood cells at concentrations of up to 350 mM, about 10(7) times its concentration found in seawater. There are approximately 10 different types of blood cell in ascidians. The identity of the true vanadium-containing blood cell (vanadocyte) is controversial and little is known about the subcellular distribution of vanadium. A scanning x-ray microscope installed at the ID21 beamline of the European Synchroton Radiation Facility to visualize vanadium in ascidian blood cells. Without fixation, freezing or staining realized the visualization of vanadium localized in living signet ring cells and vacuolated amoebocytes of two vanadium-rich ascidian species, Phallusia mammillata and Ascidia sydneiensis samea. A combination of transmission and fluorescence images of signet ring cells suggested that in both species the vacuoles contain vanadium.

Molecular cloning and expression of a human chondroitin synthase

We have identified a human chondroitin synthase from the HUGE (human unidentified gene-encoded large proteins) protein data base by screening with two keywords: "one transmembrane domain" and "galactosyltransferase family." The identified protein consists of 802 amino acids with a type II transmembrane protein topology. The protein showed weak homology to the beta1,3-galactosyltransferase family on the amino-terminal side and to the beta1,4-galactosyltransferase family on the carboxyl-terminal side. The expression of a soluble recombinant form of the protein in COS-1 cells produced an active enzyme, which transferred not only the glucuronic acid (GlcUA) from UDP-[(14)C]GlcUA but also N-acetylgalactosamine (GalNAc) from UDP-[(3)H]GalNAc to the polymer chondroitin. Identification of the reaction products demonstrated that the enzyme was chondroitin synthase, with both beta1,3-GlcUA transferase and beta1,4-GalNAc transferase activities. The coding region of the chondroitin synthase was divided into three discrete exons and localized to chromosome 15. Northern blot analysis revealed that the chondroitin synthase gene exhibited ubiquitous but markedly differential expression in the human tissues examined. Thus, we demonstrated that analogous to human heparan sulfate polymerases, the single polypeptide chondroitin synthase possesses two glycosyltransferase activities required for chain polymerization.

Subunit C of the vacuolar-type ATPase from the vanadium-rich ascidian Ascidia sydneiensis samea rescued the pH sensitivity of yeast vma5 mutants

A vanadium-accumulating ascidian, Ascidia sydneiensis samea, expresses vacuolar-type H(+)-ATPases (V-ATPases) on the vacuole membrane of the vanadium-containing blood cells known as vanadocytes. Previously, we showed that the contents of their vacuoles are extremely acidic and that a V-ATPase-specific inhibitor, bafilomycin A(1), neutralized the contents of the vacuoles. To understand the function of V-ATPase in vanadocytes, we isolated complementary DNA encoding subunit C of V-ATPase from vanadocytes because this subunit has been known to be responsible for the assembly of V-ATPases and to regulate the ATPase activity of V-ATPases. The cloned cDNA was 1443 nucleotides in length, and encoded a putative 384 amino acid protein. By expressing the ascidian cDNA for subunit C under the control of a galactose-inducible promoter, the pH-sensitive phenotype of the corresponding vma5 mutant of a budding yeast was rescued. This result showed that the ascidian cDNA for subunit C functioned in yeast cells.

[Changes in otoacoustic emission during the glycerol test in the ears of patients with Meniere's disease]

Monitoring of cochlear function is one proposed clinical application of otoacoustic emission (OAE). To determine the clinical utility of OAE in monitoring, we studied changes in OAE during the glycerol test used to diagnose endolymphatic hydrops. Transiently evoked OAE (TEOAE) and distortion product OAE (DPOAE) were measured before and 3 hours after oral administration of glycerol in 22 ears of patients with Meniere's disease. The positive result in the glycerol test was observed in 11 of 22 ears. TEOAE was recorded using a nonlinear click stimulus, and total echo power (TEP) of the whole response and filtered echo power (FEP) of its mid-frequency (1000-2000 Hz) component were used as TEOAE parameters. The growth functions of DPOAE were recorded at 3 F2 frequencies--1000, 1500, and 2000 Hz. Changes in the growth function were determined based on changes in 2 parameters--maximum level and detection threshold of DPOAE. When changes in these 4 parameters exceeded 2 standard deviations above mean test-retest variability determined from OAE data for 17 normal ears, they were considered significant. Significant changes indicating improved cochlear function in 4 OAE parameters or the appearance of OAE during the glycerol test were judged positive for OAE. Regardless of glycerol test results, positive findings were observed in both OAEs whenever a pure-tone threshold at 1000 or 2000 Hz improved. However, even in ears for which pure-tone thresholds at these frequencies did not improve, both OAEs frequently exhibited positive findings. In all ears with a positive result in the glycerol test, positive findings were observed in DPOAE, but not in TEOAE. Of the 2 parameters of TEOAE, FEP always exhibited a positive finding in ears with a positive TEP finding and FEP positivity was higher than that of TEP. In DPOAE, no cases showed a positive finding only at F2 = 2000 Hz, and DPOAE at F2 = 1000 Hz could not be detected in 4 ears due to high noise floor. Overall, positive findings were obtained in 14 ears (63.9%) for TEOAE and 20 ears (90.9%) for DPOAE. In only 1 ear were no positive findings observed in either OAE. The sensitivity of OAE measurement as a diagnostic test for endolymphatic hydrops was higher than that of pure-tone audiometry. Of the 2 OAEs, test sensitivity was much higher for DPOAE than for TEOAE. These results show that OAE measurement detects changes in cochlear function during the glycerol test more sensitively than pure-tone audiometry. They also suggest that FEP is a better indicator than TEP as a parameter of TEOAE, and that DPOAE measurement at F2 = 1000 and 1500 Hz is sufficient for practical clinical use. However, of the 2 OAEs, DPOAE was considered more appropriate than TEOAE for monitoring during the glycerol test because of its high sensitivity in detection of changes in cochlear function. In conclusion, clinical use of OAE, especially DPOAE, as a test complementary to pure-tone audiometry during the glycerol test is very useful and will improve the diagnosis of endolymphatic hydrops.

Pleural-changes in the lung allograft during acute rejection

To ascertain the cause of pleural fibrosis in lung allografts, pleural changes were investigated in rat syngeneic and allogeneic lung grafts. The pleura of lung syngeneic grafts showed no pathological changes except for mild edema on the first day after transplantation. In lung allografts, recipient cells migrated into the subpleural tissue early after transplantation (latent phase). In the vascuar phase, recipient lymphocytes in the subpleural tissue increased in number, while almost all alveolar structures were free from infiltration. Both CD4-positive and CD8-positive cells infiltrated in almost equal numbers with macrophages. The subsets of infiltrating cells were similar to those of the perivascular and peribronchial areas. In the late vascular or alveolar phase, fibroblasts were observed among the infiltrating cells, and fibrotic changes started. In the destructive phase, collagen formation with marked pleural thickening was dominant. Pulmonary acute rejection should be treated at least up to the late vascular phase to prevent pleural fibrosis.

Exclusive expression of transketolase in the vanadocytes of the vanadium-rich ascidian, Ascidia sydneiensis samea

Ascidians, especially those belonging to the Ascidiidae, are known to accumulate extremely high levels of vanadium in vanadocytes, one type of blood (coelomic) cell. Vanadium, which exists in the +5 oxidation state in seawater, is accumulated in the vanadocytes and reduced to the +3 oxidation state. We have been trying to characterize all of the polypeptides specific to vanadocytes and to specify the proteins that participate in the accumulation and reduction of vanadium. To date, we have localized three enzymes in vanadocytes: 6-phosphogluconate dehydrogenase (6-PGDH: EC 1.1.1.44), glucose-6-phosphate dehydrogenase (G6PDH: EC 1.1.1.49), and glycogen phosphorylase (GP: EC 2.4.1.1), all of which are involved in the pentose phosphate pathway. In the current study, we cloned a cDNA for transketolase, an essential and rate-limiting enzyme in the non-oxidative part of the pentose phosphate pathway, from vanadocytes. The cDNA encoded a protein of 624 amino acids, which showed 61.8% identity to the human adult-type transketolase gene product. By immunocytochemistry and immunoblot analyses, the transketolase was revealed to be a protein that was expressed only in vanadocytes and not in any of the more than ten other types of blood cell. This finding, taken together with the localized expression of the other three enzymes, strongly supports the hypothesis that the pentose phosphate pathway functions exclusively in vanadocytes.

Mediastinal esophageal cyst causing unilateral hyperlucent lung

Unilateral emphysema secondary to bronchial obstruction by a foregut-derived mediastinal cyst is rare. Here we describe an infant with a unilateral hyperlucent lung due to compression on the left main bronchus by an esophageal cyst, visualized by chest computed tomography and magnetic resonance imaging. A chest roentgenogram and a perfusion scan presented the normalized left lung after resection of the cyst.

Two cases of repeatedly recurrent atypical thymoma

Two cases of repeatedly recurrent thymoma with myasthenia gravis are detailed here. A 41-year-old woman had 5 recurrent thymomas, including local recurrences and lumbar and lung metastases; she was alive at the time of this writing, which was 22 years after her first surgery. A 36-year-old man had 3 recurrent thymomas, including local recurrence, dissemination, and lung metastasis; he was alive at the time of this writing, which was 16 years after his first surgery. Both recurrent lesions were diagnosed as "atypical thymoma" with moderate nuclear atypia. The patients with atypical thymoma must be followed up carefully due to a possible recurrence. Surgical treatment with chemoradiotherapy can lengthen their survival.

High frequency expressions of CD44 standard and variant forms in non-small cell lung cancers, but not in small cell lung cancers

BACKGROUND AND OBJECTIVES

Organ specificity has been demonstrated in the mode of CD44 expression among several cancers.

METHODS

We examined the expressions of CD44 standard (CD44s) and CD44 variants (CD44v) in 14 cell lines (small cell lung cancer (SCLC): 5, non-small cell lung cancer (NSCLC): 9 and 20 surgically resected samples (SCLC: 7, NSCLC: 13) of lung cancer using reverse transcription polymerase chain reaction and immunohistochemistry.

RESULTS

Although both NSCLC and SCLC expressed CD44s, the frequency and intensity of CD44s expression in NSCLC were different from those in SCLC: cell lines, 89% vs. 40%; tumor samples, 100% (diffusely stained) vs. 57% (focally stained). CD44s expression was partially or completely repressed in SCLC. However, NSCLC frequently expressed CD44v, but SCLC expressed infrequently: cell lines, 67% vs. 20%; tumor samples, 69% vs. 0%. The N-417 line, which only expressed some CD44v in SCLC, falls SCLC and NSCLC both in biomarkers and in growth patterns.

CONCLUSIONS

CD44 expression was repressed in SCLC but was enhanced in NSCLC.

6-Phosphogluconate dehydrogenase is a 45-kDa antigen recognized by S4D5, a monoclonal antibody specific to vanadocytes in the vanadium-rich ascidian Ascidia sydneiensis samea

We previously prepared a monoclonal antibody, S4D5, specific to vanadocytes, vanadium-containing blood cells, in the vanadium-rich ascidian Ascidia sydneiensis samea. Here, we demonstrate that a 45-kDa antigen recognized by S4D5 is 6-phosphogluconate dehydrogenase (6-PGDH), an enzyme of the pentose phosphate pathway, based on cDNA isolation of RNA samples from blood cells of the ascidian. Western blot analysis confirmed an abundance of 6-PGDH protein in the vanadocytes and localization of 6-PGDH in the soluble extract of the blood cells. Soluble protein exhibited a correspondingly high level of 6-PGDH enzymatic activity. Ascidians are known to selectively accumulate high levels of vanadium in vanadocytes, and the highest recorded concentration of accumulated vanadium is 350 mM, which is 10(7) times the concentration in sea water. Almost all vanadium ions are reduced to the +3 oxidation state via the +4 oxidation state in vanadocytes, indicating that reducing agents must participate in the accumulation. On the other hand, vanadium ions in the +5 oxidation state are reduced to the +4 oxidation state by the presence of NADPH in vitro. Together, these observations suggest that NADPH produced in the pentose phosphate pathway may conjugate the reduction of vanadium from the +5 oxidation state through the +4 oxidation state in vanadocytes of ascidians.

Value of mass screening for thyroid cancer

This study aims to clarify the presently uncertain value of mass screening for thyroid cancer, which has been performed by physical examination along with mass screening for breast cancer in Zentsuji, Japan since 1983. Among 18,619 subjects, 36 individuals with thyroid cancer (0.19%) were found. The detection rate was 0.40% at the initial screening and 0.10% during subsequent periodic screening. All thyroid cancers were confirmed histologically as well differentiated carcinoma. The tumor size in the mass-screening group (14 +/- 6 mm) was significantly smaller than in patients presenting at an outpatient clinic during the same period (19 +/- 13 mm) (p < 0.05). The incidence of nodal metastases in the mass-screening group (38%) was significantly lower than in the outpatient group (68%) (p < 0.05). Thus mass screening seemed to find thyroid cancers in a relatively early stage. Mass screening for thyroid cancer was economic in this instance because it was performed together with screening for other cancers, such as breast cancer. Thyroid cancer screening required less than one additional minute per subject. The ultimate aim of mass screening is to reduce mortality. No improvement in prognosis from enforced mass screening for thyroid cancer was detected in this study. It cannot be demonstrated that there is sufficient value of mass screening for thyroid cancer to perform it independently despite early cancer detection.

Mutations of the p53 gene in human lung cancer from chromate-exposed workers

We examined p53 mutations in 20 cancer samples from 19 chromate workers with lung cancer by Polymerase chain reaction-Single strand conformation polymorphism analysis and direct sequencing. Six missense mutations were identified in 4 (20%) of the 20 chromate lung cancer samples. Fewer mutations were found in the patients with lung cancers who had been exposed to chromate than in those who had not. However, the pattern of p53 mutations in lung cancer patients exposed to chromate differed from that of common lung cancers in 3 respects. There were no apparent G to T transversions, which are common base changes in lung cancers. Half of the mutational sites (3/ 6) had changes of AT base-pairs, and 2 of 4 mutational tumor samples had double missense mutations. Our results suggested that chromate exposure may induce point mutation of the p53 gene.