3D-culture system for heart regeneration and cardiac medicine

3D cultures have gained attention in the field of regenerative medicine for their usefulness as in vitro model of solid tissues. Bottom-up technology to generate artificial tissues or organs is prospective and an attractive approach that will expand as the field of regenerative medicine becomes more translational. We have characterized c-kit positive cardiac stem cells after long-term cultures and established a 3D-nanoculture system using collagen scaffolds. By combining informatics-based studies, including proteomic analyses and microarrays, we sought to generate methods that modeled cardiac regeneration which can ultimately be used to build artificial hearts. Here, we describe the use of biodegradable beads or 3D cultures to study cardiac regeneration. We summarize recent work that demonstrates that, by using a combination of molecular analyses with 3D cultures, it is possible to evaluate concise mechanisms of solid tissue stem cell biology.

Clinical features of adult patients with Eisenmenger's syndrome in Japan and Korea

BACKGROUND

There are few articles on mortality and morbidity of adult patients with Eisenmenger's syndrome (ES) in the current era when disease targeting therapy (DTT) has been available.

METHODS AND RESULTS

198 patients (a median age 35 years, 64% female) with ES who visited the 16 participating institutes in Japan and Korea from 1998 to 2009 were enrolled. Clinical data during adulthood were collected from each institutional chart and analyzed centrally. During a median follow-up of 8 years, 30 patients died including 14 sudden deaths. 89 patients took oral medication of DTT and clinical improvement was observed in 54 of them. However, survival rate in patients taking DTT was not different from those without (87% vs 84%, p=0.55). When the clinical data in between first and last clinic visits were compared in 85 patients, the patients with NYHA >/=III increased from 24% to 48% (p<0.001), SpO2 decreased from 89% to 85% (p=0.008) and hematocrit increased from 51.4% to 52.9% (p=0.04). Non-survivors had poorer NYHA function class, lower body weight (BW), lower body mass index (BMI), and higher serum level of Cr at the first visits than survivors.

CONCLUSIONS

Long term survival and clinical status of adult patients with ES remains unsatisfactory even in the current era of DTT. Poor NYHA functional class, low BW, low BMI and high serum level of Cr were related to mortality. DTT therapy improved clinical status in many patients with Eisenmenger's syndrome, but no significant impact on survival could be shown.

Phase III randomised controlled trial of neoadjuvant chemotherapy plus radical surgery vs radical surgery alone for stages IB2, IIA2, and IIB cervical cancer: a Japan Clinical Oncology Group trial (JCOG 0102)

Background:

A phase III trial was conducted to determine whether neoadjuvant chemotherapy (NACT) before radical surgery (RS) improves overall survival.

Methods:

Patients with stage IB2, IIA2, or IIB squamous cell carcinoma of the uterine cervix were randomly assigned to receive either BOMP (bleomycin 7 mg days 1–5, vincristine 0.7 mg m⁻² day 5, mitomycin 7 mg m⁻² day 5, cisplatin 14 mg m⁻² days 1–5, every 3 weeks for 2 to 4 cycles) plus RS (NACT group) or RS alone (RS group). Patients with pathological high-risk factors received postoperative radiotherapy (RT). The primary end point was overall survival.

Results:

A total of 134 patients were randomly assigned to treatment. This study was prematurely terminated at the first planned interim analysis because overall survival in the NACT group was inferior to that in the RS group. Patients who received postoperative RT were significantly lower in the NACT group (58%) than in the RS group (80% P=0.015). The 5-year overall survival was 70.0% in the NACT group and 74.4% in the RS group (P=0.85).

Conclusion:

Neoadjuvant chemotherapy with BOMP regimen before RS did not improve overall survival, but reduced the number of patients who received postoperative RT.

Mutations in the cardiac troponin T gene show various prognoses in Japanese patients with hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is an autosomal dominant disorder resulting from mutations in genes for at least 15 various sarcomere-related proteins including cardiac β-myosin heavy chain, cardiac myosin-binding protein C, and cardiac troponin T. The troponin T gene (TNNT2) mutation has the third incidence of familial HCM, and the genotype–phenotype correlation of this gene still remains insufficient in Japanese familial HCM. Therefore, in the present study, we focused on screening the TNNT2 mutation in 173 unrelated Japanese patients with familial HCM, and found three reported mutations and a new mutation of TNNT2 in 11 individuals from four families. In these families, two individuals from one family had double mutations, Arg130Cys and Phe110Ile, six individuals from two other families had an Arg92Trp mutation, and one individual of another family had a new mutation, Ile79Thr, of TNNT2. The phenotype of each family was often different from reported cases, even if they had the same genetic mutation. In addition, families with the same genetic mutation showed a similar trend in the phenotype, but it was not exactly the same. However, sudden death in youth was observed in all of these families. Although the type of genetic mutation is not useful for predicting prognosis in HCM, the possibility of sudden cardiac death remains. Therefore, the prognosis of individuals bearing the TNNT2 mutation with familial HCM should be more carefully observed from birth.

Assessment of mechanical dyssynchrony in fulminant myocarditis

It is often difficult to assess ventricular synchrony in patients with fulminant myocarditis. We report a pediatric case of fulminant myocarditis where clinical course and changes in dyssynchrony were followed with speckle tracking echocardiography. Dyssynchrony of the left ventricle changed day by day. It was useful to assess the progression of ventricular damage and its recovery.

Neonatal dural arteriovenous fistula at the confluence presenting with paralysis of the orbicularis oris muscle

A male neonate presented a dural arteriovenous fistula (DAVF) at the confluence with paralysis of the orbicularis oris muscle. The interesting features in our case were the clinical symptoms (orbicularis oris muscle paralysis at birth), angioarchitecture (high-flow arteriovenous shunts at the confluence) and the size and hemodynamic flow (mid-sized venous pouch) of the fistula. Additionally, the embolization technique (i.e., occipital artery approach, closing shunts with pure glue) automatically resulted in the immediate and complete closure of accessory feeders without any additional treatment, and the midterm clinical outcome was good. We succeeded improving the symptoms of a neonate with a congenital high-flow DAVF by closing a fistula using a small amount of glue.

Cardiomyocyte regeneration

The heart was initially believed to be a terminally differentiated organ; once the cardiomyocytes died, no recovery could be made to replace the dead cells. However, around a decade ago, the concept of cardiac stem cells (CSCs) in adult hearts was proposed. CSCs differentiate into cardiomyocytes, keeping the heart functioning. Studies have proved the existence of stem cells in the heart. These somatic stem cells have been studied for use in cardiac regeneration. Moreover, recently, induced pluripotent stem cells (iPSCs) were invented, and methodologies have now been developed to induce stable cardiomyocyte differentiation and purification of mature cardiomyocytes. A reprogramming method has also been applied to direct reprogramming using cardiac fibroblasts into cardiomyocytes. Here, we address cardiomyocyte differentiation of CSCs and iPSCs. Furthermore, we describe the potential of CSCs in regenerative biology and regenerative medicine.

Hesr2 knockout mice develop aortic valve disease with advancing age

OBJECTIVE

Acquired heart diseases, such as valve disease, are major causes of human morbidity and mortality. However, the pathological mechanisms underlying these diseases are largely unknown. Our aim is to identify the role of the hairy and enhancer of split-related (Hesr)-2 gene in the adult heart.

METHODS AND RESULTS

Echocardiography detected heart dysfunctions indicative of aortic valve anomalies, stenosis, and regurgitation, in ≈59% of >12-month-old Hesr2 knockout survivor mice. Morphological and histological analyses revealed thickened semilunar valves with increased fibrotic areas, indicating that sclerotic degeneration of valves is the main cause of aortic valve disease. The expression of osteogenic genes, such as osteopontin and sclerostin, were upregulated in the mutants, and the overexpression of sclerostin in endothelial cells resulted in thickened semilunar valves with increased fibrotic areas, similar to that seen in the Hesr2 knockout mice, suggesting that Hesr2 can regulate osteogenic gene expression in valves. Reduced left ventricular function, which may be caused by increased ventricular interstitial fibrosis, and enlarged myocardial cell size without ventricular wall thickening were found in both aortic valve stenosis/regurgitation-positive (33%) and aortic valve stenosis/regurgitation-negative (38%) subpopulations in 12-month-old survivor mice. Dilated left ventricular internal dimensions were specifically detected in the aortic valve stenosis/regurgitation-positive subpopulation, thus suggesting that the degeneration of cardiomyocytes is influenced by irregular hemodynamics.

CONCLUSIONS

These data revealed that survivor mice lacking the Hesr2 gene exhibit fibrosis in the aortic valve and ventricle in adulthood, thus suggesting that Hesr2 plays an important role in maintaining the homeostasis of the aortic valve and ventricle.

Congenital giant cardiac tumor with severe left-ventricular inflow and outflow obstruction and arrhythmia treated with pulmonary artery banding and long-term amiodarone infusion

We report a congenital giant cardiac tumor that occupied the majority of left ventricular cavity with severe left ventricular inflow and outflow obstruction. The hemodynamics were similar to univentricular physiology. He was treated with prostaglandins and bilateral pulmonary artery banding. He had frequent supraventricular tachycardia associated with ventricular pre-excitation that was controlled by long-term administration of intravenous amiodarone. The patient died due to sepsis after 3 months.

Outcomes of childhood pulmonary arterial hypertension in BMPR2 and ALK1 mutation carriers

Mutations in the bone morphogenetic protein receptor type 2 (BMPR2) gene and the activin receptor-like kinase 1 (ALK1) gene have been reported in heritable pulmonary arterial hypertension (HPAH) and idiopathic pulmonary arterial hypertension (IPAH). However, the relation between clinical characteristics and each gene mutation in IPAH and HPAH is still unclear, especially in childhood. The aim of this study was to determine, in a retrospective study, the influence and clinical outcomes of gene mutations in childhood IPAH and HPAH. Fifty-four patients with IPAH or HPAH whose onset of disease was at <16 years of age were included. Functional characteristics, hemodynamic parameters, and clinical outcomes were compared in BMPR2 and ALK1 mutation carriers and noncarriers. Overall 5-year survival for all patients was 76%. Eighteen BMPR2 mutation carriers and 7 ALK1 mutation carriers were detected in the 54 patients with childhood IPAH or HPAH. Five-year survival was lower in BMPR2 mutation carriers than mutation noncarriers (55% vs 90%, hazard ratio 12.54, p = 0.0003). ALK1 mutation carriers also had a tendency to have worse outcome than mutation noncarriers (5-year survival rate 64%, hazard ratio 5.14, p = 0.1205). In conclusion, patients with childhood IPAH or HPAH with BMPR2 mutation have the poorest clinical outcomes. ALK1 mutation carriers tended to have worse outcomes than mutation noncarriers. It is important to consider aggressive treatment for BMPR2 or ALK1 mutation carriers.

Lactation persistency as a component trait of the selection index and increase in reliability by using single nucleotide polymorphism in net merit defined as the first five lactation milk yields and herd life

We first sought to clarify the effects of discounted rate, survival rate, and lactation persistency as a component trait of the selection index on net merit, defined as the first five lactation milks and herd life (HL) weighted by 1 and 0.389 (currently used in Japan), respectively, in units of genetic standard deviation. Survival rate increased the relative economic importance of later lactation traits and the first five lactation milk yields during the first 120 months from the start of the breeding scheme. In contrast, reliabilities of the estimated breeding value (EBV) in later lactation traits are lower than those of earlier lactation traits. We then sought to clarify the effects of applying single nucleotide polymorphism (SNP) on net merit to improve the reliability of EBV of later lactation traits to maximize their increased economic importance due to increase in survival rate. Net merit, selection accuracy, and HL increased by adding lactation persistency to the selection index whose component traits were only milk yields. Lactation persistency of the second and (especially) third parities contributed to increasing HL while maintaining the first five lactation milk yields compared with the selection index whose only component traits were milk yields. A selection index comprising the first three lactation milk yields and persistency accounted for 99.4% of net merit derived from a selection index whose components were identical to those for net merit. We consider that the selection index comprising the first three lactation milk yields and persistency is a practical method for increasing lifetime milk yield in the absence of data regarding HL. Applying SNP to the second- and third-lactation traits and HL increased net merit and HL by maximizing the increased economic importance of later lactation traits, reducing the effect of first-lactation milk yield on HL (genetic correlation (rG) = -0.006), and by augmenting the effects of the second- and third-lactation milk yields on HL (rG = 0.118 and 0.257, respectively).

Follow up of the 987 blood donors found with hepatitis C virus infection over 9-18 years

AIM

  To follow up blood donors found with hepatitis C virus (HCV) infection, to improve the outcome by antiviral treatments.

METHODS

  Between 1991 and 2001, 3377 of the 1 925 860 donors (0.18%) were found to have HCV infection at the Hiroshima Red Cross Blood Center in Japan. Of them, 987 were able to be followed regularly over 9-18 years until 2009, and received antiviral treatments as required.

RESULTS

  At the start, chronic hepatitis was diagnosed in 541 (54.8%), cirrhosis in five (0.5%) and hepatocellular carcinoma (HCC) in one (0.1%), whereas the remaining 439 (44.5%) had persistently normal aminotransferase levels (PNAL). Hospital visits were terminated voluntarily in 24.3% within the first year, 46.8% by 10 years and 50.9% by 17 years. Liver disease improved in 178 (18.0%), remained stable in 606 (61.4%) and aggravated in 170 (17.2%). Of the 541 donors with chronic hepatitis, HCC developed in 28 (5.2%) and cirrhosis in 11 (2.0%), whereas HCV infection was cleared in 107 (19.8%) by antiviral treatments. In addition, HCV infection resolved in 54 of the 439 donors (12.3%) with PNAL after they had developed chronic hepatitis and received treatments. In donors with chronic hepatitis, the cumulative incidence of HCC was 4.1% at 10 years. By multivariate analysis, age and diagnosis of chronic hepatitis at the entry were found to be independent risk factors for the development of HCC.

CONCLUSION

  Individuals with undiagnosed HCV infection need to be identified and receive medical care. They have to be motivated to merit from this health-care program.