Induction of tissue-specific stem cells by reprogramming factors, and tissue-specific selection

Although induced pluripotent stem (iPS) cells have significant implications for overcoming most of the ethical issues associated with embryonic stem (ES) cells, there are still several unresolved issues related to the use of iPS cells for clinical applications, such as teratoma formation. In this study, we were able to generate tissue-specific stem (induced tissue-specific stem; iTS) cells from the pancreas (iTS-P) or liver (iTS-L) by transient overexpression of reprogramming factors, combined with tissue-specific selection. The generation of iTS cells was easier than that of iPS cells. The iTS-P/iTS-L cells express genetic markers of endoderm and pancreatic/hepatic progenitors and were able to differentiate into insulin-producing cells/hepatocytes more efficiently than ES cells. Subcutaneous transplantation of both types of iTS cells into immunodeficient mice resulted in no teratoma formation. The technology used for the transient overexpression of reprogramming factors and tissue-specific selection may be useful for the generation of other tissue-specific stem cells, and the generation of iTS cells could have important implications for the clinical application of stem cells.

Prediction model for glucose metabolism based on lipid metabolism

OBJECTIVES

We developed a robust, long-term clinical prediction model to predict conditions leading to early diabetes using laboratory values other than blood glucose and insulin levels. Our model protects against missing data and noise that occur during long-term analysis.

METHODS

RESULTS of a 75-g oral glucose tolerance test (OGTT) were divided into three groups: diabetes, impaired glucose tolerance (IGT), and normal (n = 114, 235, and 325, respectively). For glucose metabolic and lipid metabolic parameters, near 30-day mean values and 10-year integrated values were compared. The relation between high-density lipoprotein cholesterol (HDL-C) and variations in HbA1c was analyzed in 158 patients. We also constructed a state space model consisting of an observation model (HDL-C and HbA1c) and an internal model (disorders of lipid metabolism and glucose metabolism) and applied this model to 116 cases.

RESULTS

The root mean square error between the observed HbA1c and predicted HbA1c was 0.25.

CONCLUSIONS

In the observation model, HDL-C levels were useful for prediction of increases in HbA1c. Even with numerous missing values over time, as occurs in clinical practice, clinically valid predictions can be made using this state space model.

Thoracic endometriosis-related pneumothorax distinguished from primary spontaneous pneumothorax in females

PURPOSE

Thoracic endometriosis-related pneumothorax (TERP) is a secondary condition specific for females, but in a clinical setting, TERP often is difficult to distinguish from primary spontaneous pneumothorax (PSP) based on a relationship between the dates of pneumothorax and menstruation. The purpose of this study was to clarify the clinical features of TERP compared with PSP.

METHODS

We retrospectively reviewed the clinical and histopathological files of female patients with pneumothorax who underwent video-assisted thoracoscopic surgery in the Pneumothorax Research Center during the 6-year period from January 2005 to December 2010. We analyzed the clinical differences between TERP and PSP.

RESULTS

The study included a total of 393 female patients with spontaneous pneumothorax, of whom 92 (23.4 %) were diagnosed as having TERP and 33.6 % (132/393) as having PSP. We identified four factors (right-sided pneumothorax, history of pelvic endometriosis, age ≥31 years, and no smoking history) that were statistically significant for predicting TERP and assigned 6, 5, 4, and 3 points, respectively, to establish a scoring system with a calculated score from 0 to 18. The cutoff values of a calculated score ≥12 yielded the highest positive predictive value (86 %; 95 % confidence interval (CI) 81.5-90.5 %) for TERP and negative predictive value (95.2 %; 95 % CI 92.3-98 %) for PSP.

CONCLUSIONS

TERP has several distinct clinical features from PSP. Our scoring system consists of only four clinical variables that are easily obtainable and enables us to suspect TERP in female patients with pneumothorax.

Characterization of pulmonary cysts in Birt-Hogg-Dubé syndrome: histopathological and morphometric analysis of 229 pulmonary cysts from 50 unrelated patients

Aims

To characterize the pathological features of pulmonary cysts, and to elucidate the possible mechanism of cyst formation in the lungs of patients with Birt–Hogg–Dubé syndrome (BHDS), a tumour suppressor gene syndrome, using histological and morphometric analyses.

Methods and results

We evaluated 229 lung cysts from 50 patients with BHDS and 117 from 34 patients with primary spontaneous pneumothorax (PSP) for their number, size, location and absence or presence of inflammation. The BHDS cysts abutted on interlobular septa (88.2%) and had intracystic septa (13.6%) or protruding venules (39.5%) without cell proliferation or inflammation. The frequencies of these histological characteristics differed significantly from those seen in the lungs of patients with PSP (P < 0.05). Although the intrapulmonary BHDS cysts were smaller than the subpleural BHDS cysts (P < 0.001), there was no difference in size between them when there was no inflammation. The number of cysts diminished logarithmically and the proportion of cysts with inflammation increased as their individual sizes became greater (P < 0.05).

Conclusions

These results imply that the BHDS cysts are likely to develop in the periacinar region, an anatomically weak site in a primary lobule, where alveoli attach to connective tissue septa. We hypothesize that the BHDS cysts possibly expand in size as the alveolar walls disappear at the alveolar-septal junction, and grow even larger when several cysts fuse.

Different expression patterns of hepatic cytochrome P450 s during anaphylactic or lipopolysaccharide-induced inflammation

Certain physiological states and diseases can alter the expression and activity of cytochrome P450 s (CYPs), which have the potential to cause unexpected adverse effects. We previously demonstrated that lipopolysaccharide (LPS)-induced inflammation attenuates the induction of CYPs by xenobiotics in mouse liver. In this study, to investigate whether anaphylaxis-induced inflammation affects the hepatic CYPs' expression, we examined the effects of ovalbumin (OVA)-induced anaphylaxis on constitutive CYP mRNA and protein expressions. We also compared these effects with those obtained with LPS treatment. In addition, we examined the tumor necrosis factor (TNF) alpha and interleukin (IL)-113 mRNA levels, because these cytokines are known to be induced by LPS treatment and anaphylactic reactions. LPS treatment decreased the constitutively expressed Cyp1a2, Cyp2c29, and Cyp3al 1 mRNAs, and increased the TNFalpha and IL-1beta mRNAs. LPS treatment also decreased the CYP1A2 and CYP3A protein levels. Anaphylaxis, on the other hand, did not change the levels of the constitutively expressed Cyp1a2, Cyp2c29, or Cyp3a1 1 mRNAs, although it increased the TNFalpha and IL-1beta mRNAs, as observed in the LPS-treated mice. These results suggest that anaphylaxis-induced inflammation had less effect than LPS-induced inflammation on these CYPs in the liver. In contrast, we observed that the expressions of Cyp2b10 mRNA and its protein were quite different from those of the other CYPs in both the anaphylactic and LPS-treated mice. Our findings strongly suggest that the alteration of the constitutive CYPs' expression levels during inflammation varies according to the immunostimulation pathway.

Diagnostic laparoscopy identifies a peritoneal adenomatoid-like mesothelioma masquerading as ovarian cancer: a case report

The authors report a rare case of peritoneal adenomatoid mesothelioma in a woman with no history of asbestos exposure. A 61-year-old woman was originally suspected of having a bilateral ovarian tumor based on chest radiography and magnetic resonance imaging (MRI). Upon referral to our hospital, the presence of two solid masses was confirmed by enhanced MRI and 18F-fluorodeoxyglucose positron-emission tomography/computed tomography (18F-FDG-PET/CT). Physical examination was normal, as were serum concentrations of the tumor markers CA 19-9, CA 125, and CEA. Laparoscopic surgery showed a right ovarian tumor and laparoscopic right salpingo-oophorectomy and adhesiotomy were performed. Two months later, the patient underwent laparoscopic segmental resection of the sigmoid colon, with histological analysis identifying an adenomatoid-like tumor. The final diagnosis was peritoneal adenomatoid-like mesothelioma with invasion of the right ovary. This case report demonstrates that imaging techniques must be coupled with laparoscopic surgery for an accurate diagnosis of peritoneal mesothelioma.

Phantom experiment and clinical utility of quantitative shear wave elastography for differentiating thyroid nodules

Shear wave elastography (SWE) using acoustic radiation force impulse (ARFI) is a novel ultrasonography technique. The aim of this study was to investigate the clinical usefulness of quantitative SWE for differentiating thyroid nodules. For phantom study, we measured the shear wave velocities (SWVs) of the four spheres of 2- and 1-cm diameters with varying hardness. For clinical study, the SWVs of normal thyroid glands and thyroid nodules, that were classified as benign or malignant according to either cytological or pathological findings, were measured. The SWVs of each thyroid patient were compared with that of a normal thyroid and each other. In phantom study, the SWVs for the 2-cm spheres correlated with the hardness of the targets, whereas the values for the 1-cm spheres did not. In clinical study, 112 nodules identified in 167 patients and 94 normal thyroid glands were analyzed according to the criteria for the study. The nodules included 84 benign nodules, and 28 papillary carcinoma. The mean SWVs of each group were 1.64 ± 0.47 m/s for normal thyroid, 1.88 ± 0.62 m/s for benign nodules and 2.67 ± 0.76 m/s for papillary carcinoma. The SWVs of papillary carcinoma were significantly higher than those of benign nodules (P < 0.001). The area under the ROC curve was 0.809 with a cut-off value of 2.01 m/s. The sensitivity and specificity were 85.7% and 62.0% respectively. Results showed that SWE provides new information on tumor characteristics, such as hardness and larger nodules tended to provide stable measurements.

Outcome of fertility-sparing treatment with medroxyprogesterone acetate for atypical hyperplasia and endometrial carcinoma in young Japanese women

PURPOSE

To review the outcome in patients with atypical endometrial hyperplasia (AEH) and endometrial cancer (EC) who received MPA treatment in the present hospital.

MATERIALS AND METHODS

Patients with AEH or EC were administered MPA for 12 weeks followed by endometrial curettage. The rates of effect, recurrence, pregnancy, and complications were evaluated. The changes in progesterone receptors and FOXO-1, known as a target of MPA treatment, were examined by immunostaining.

RESULTS

Four of seven patients with endometrial cancer and three of three patients with AH had complete response. Four of seven patients had recurred within one year after the treatment and had to undergo hysterectomy. None of the patients showed changes in progesterone receptors. Although six of seven patients were negative for FOXO-1 before and after treatment, all the patients showed increased developments of FOXO-1 during MPA treatment.

CONCLUSION

Progestin as a fertility-preserving treatment is expected to be effective for endometrial cancer, but judicious use might be required because it shows high rate of recurrence. Further studies regarding the mechanism may be necessary to achieve high efficacy.

Efficacy and safety of low-dose sirolimus for treatment of lymphangioleiomyomatosis

BACKGROUND

Lymphangioleiomyomatosis (LAM) is a rare disease caused by dysregulated activation of the mammalian target of rapamycin (mTOR). Sirolimus, an inhibitor of mTOR, has been reported to decrease the size of angiomyolipomas and stabilize pulmonary function in patients with LAM. However, the optimal dose for the treatment of LAM remains unclear.

METHODS

We conducted a retrospective, observational study of 15 patients with LAM who underwent sirolimus therapy for more than 6 months. The efficacy was evaluated by reviewing the patients' clinical courses, pulmonary function and chest radiologic findings before and after the initiation of sirolimus treatment.

RESULTS

All patients had blood trough levels of sirolimus lower than 5ng/mL. Sirolimus treatment improved the annual rates of change in FVC and FEV1 in the 9 patients who were free from chylous effusion (FVC, -101.0 vs. +190.0mL/y, p=0.046 and FEV1, -115.4 vs. +127.8mL/y, p=0.015). The remaining 7 patients had chylous effusion at the start of sirolimus treatment; the chylothorax resolved completely within 1-5 months of treatment in 6 of these cases. These results resembled those of previous studies in which blood trough levels of sirolimus ranged from 5 to 15ng/mL.

CONCLUSIONS

Low-dose sirolimus (trough level, 5ng/mL or less) performed as well as the higher doses used previously for improving pulmonary function and decreasing chylous effusion in patients with LAM.

Immunohistochemical analysis of thoracic endometriosis

Thoracic endometriosis is a rare disease responsible for catamenial pneumothorax. The immunohistochemical features of thoracic endometriosis are not well understood. An immunohistochemical examination of 84 diaphragmatic specimens of catamenial pneumothorax using antibodies against estrogen receptor (ER), progesterone receptor (PgR), CD10 and smooth muscle actin (SMA) was conducted. The endometrial tissue was small, and focally located around the chasm of the tendon on the side of the thoracic cavity. Endometrial stroma were detected in 84/84 (100%) of the specimens, endometrial glands were detected in 21/84 (25%) and smooth muscle was detected in 1/84 (1.2%). The endometrial stroma exhibited positive staining for ER in 74/84 (88.1%) of the specimens, PgR in 84/84 (100%), CD10 in 74/84 (88.1%) and SMA in 46/84 (54.8%). Because thoracic endometriosis is small in size, and only 25% of the resected tissue specimens were accompanied with the endometrial gland, an immunohistochemical analysis can be useful for their detection. The fact that over half of the thoracic endometrial stroma showed positive staining for SMA, and the existence of thoracic endometriosis accompanied by smooth muscle, indicated that some part of the thoracic endometriosis may have the ability to differentiate into smooth muscle, although further studies are needed to confirm this hypothesis.

Hepatocyte destruction with enhanced collagen synthesis: characteristic feature of chronic hepatitis C patients on haemodialysis

Hepatitis C virus (HCV) infection is frequent among patients with end-stage renal disease on haemodialysis and is considered to be an independent risk factor for mortality in this setting. However, only a few of these patients are treated with anti-hepatitis virus treatment before the development of end-stage renal disease. Recent guidelines recommend identification of patients with good prognoses who are in need of interferon treatment, but we know little of patients who must be treated urgently. Ninety-eight patients on haemodialysis (48 anti-HCV-positive and 50 anti-HCV-negative patients) were enrolled in this study; HCV RNA was detected in 43 anti-HCV-positive patients. Univariate analysis and multivariate regression analysis were applied to identify variables independently associated with persistent HCV infection. Seven variables were proven to be associated with persistent HCV infection. Among them, type IV collagen 7S and N-terminal propeptide of type III procollagen (P-III-P) were defined as independent variables useful in distinguishing HCV RNA-positive patients from HCV RNA-negative patients with 0.91 sensitivity, 0.91 specificity, 0.89 positive predictive value and 0.93 negative predictive value. Our observations suggest that hepatocyte destruction with enhanced liver fibrosis is a characteristic clinical feature of persistent HCV infection. Type IV collagen 7S of ≥ 5 ng/mL and/or P-III-P of ≥ 5 U/mL would be useful markers to identify patients in need of interferon treatment, which supports the idea of the Kidney Disease: Improving Global Outcomes guidelines that a good prognosis in patients with HCV infection on haemodialysis should prompt consideration for IFN treatment when applicable.

Toll-like receptor 2-mediated modulation of growth and functions of regulatory T cells by oral streptococci

This study was designed to determine whether oral streptococci modulate the growth and functions of regulatory T cells. Heat-killed cells of wild-type strains of Streptococcus gordonii and Streptococcus mutans induced the Toll-like receptor 2 (TLR2) -mediated nuclear factor-κB (NF-κB) activation, but their lipoprotein-deficient strains did not. Stimulation with these streptococci resulted in a significant increase in the frequency of CD4(+) CD25(+) Foxp3(+) regulatory T cells in splenocytes derived from both TLR2(+/+) and TLR2(-/-) mice, but the level of increase in TLR2(+/+) splenocytes was stronger than that in TLR2(-/-) splenocytes. Both strains of S. gordonii enhanced the proliferation of CD4(+) CD25(+) Foxp3(+) regulatory T cells isolated from TLR2(+/+) mice at the same level as those from TLR2(-/-) mice in an interleukin-2-independent manner. However, wild-type and lipoprotein-deficient strains of both streptococci did not enhance the suppressive activity of the isolated regulatory T cells in vitro, but rather inhibited it. TLR ligands also inhibited the suppressive activity of the regulatory T cells. Inhibition of the suppressive activity was recovered by the addition of anti-IL-6 antibody. Pretreatment of antigen-presenting cells with the NF-κB inhibitor BAY11-7082 enhanced the suppressive activity of the regulatory T cells. These results suggested that interleukin-6 produced by antigen-presenting cells inhibits the suppressive activity of the regulatory T cells. Wild-type strain, but not lipoprotein-deficient strain, of S. gordonii reduced the frequency of CD4(+)  CD25(+)  Foxp3(+) regulatory T cells in the acute infection model, whereas both strains of S. gordonii increased it in the chronic infection model mice. Hence, this study suggests that oral streptococci are capable of modulating the growth and functions of regulatory T cells in vitro and in vivo.

Spontaneous pneumothorax with persistent air leakage and invasive procedures

OBJECTIVE

Prolonged air leaks in patients with spontaneous pneumothorax are not infrequent. The aim of this study was to assess the duration of air leaks and define the clinical variables associated with the therapeutic success of chest tube drainage for spontaneous pneumothorax.

METHODS

A total of 441 patients with spontaneous pneumothorax treated with chest tube drainage between 2008 and 2012 were retrospectively evaluated. The clinical differences between the patients successfully treated with drainage and those who required more invasive procedures were analyzed.

RESULTS

Invasive procedures, such as video-assisted thoracic surgery (n=121), fibrin glue administration through a chest tube (n=8) and pleurodesis with OK-432 (n=21), were performed in 34% (150/441) of the patients. The treatment rate of chest drainage alone was higher in the patients with initial pneumothorax (72%; 124/170) than in those with recurrent pneumothorax (62%; 167/271) (p=0.015). In addition, this rate was higher in the patients with moderate lung collapse (70%; 167/237) than in those with severe lung collapse (61%; 124/204) (p=0.032).

CONCLUSION

Patients with recurrent pneumothorax or severe lung collapse associated with prolonged air leakage are more likely to receive invasive procedures.