[Recovery from parkinsonism with N-acetylcysteine-differentiated neurons].

The upregulation of dopaminergic neuronal differentiation is necessary for stem cell therapy in Parkinson's disease (PD). In this study, neuronal differentiation efficiency increased by more than 2 times in P19 embryonic stem cells (ESCs) induced by N-acetylcysteine (NAC) and retinoic acid (RA) as compared to RA alone, with suppressed glial differentiation. The majority of NAC-treated stem cells grafted into brains of PD mice differentiated into dopaminergic neurons and persisted well for 6 weeks. Parkinsonism was also greatly improved after grafting NAC-treated cells in comparison to cells treated with only RA. Our results strongly suggest that NAC treatment may be an effective strategy for generating stem cells fated to become dopaminergic neurons for PD clinical therapy.

N-acetylcysteine enhances neuronal differentiation of P19 embryonic stem cells via Akt and N-cadherin activation.

We examined whether N-acetylcysteine (NAC) enhanced embryonic body (EB) formation and neuronal differentiation in terms of EB formation, neuronal marker (microtubule-associated protein 2; MAP-2) expression, and neuron maturation using P19 embryonic stem cells. The size and numbers of EBs were greatly increased, together with the up-regulated N-cadherin expression. Also, MAP-2 expression and neurite outgrowth were much increased with activation of serine/threonine protein kinase (Akt) and blocked by addition of an Akt inhibitor (LY294002). Our results suggested that NAC increased EB formation by up-regulating the N-cadherin expression. Furthermore, NAC-enhanced neuronal differentiation was mediated by activation of Akt.

Graftless sinus augmentation with simultaneous dental implant placement: clinical results and biological perspectives.

After a sinus lifting procedure, the compartment around the implants under the sinus mucosal lining in the sinus floor is filled with a blood clot from surrounding bleeding. The aim of this study was to evaluate the feasibility of bone formation following graftless sinus lifting with the simultaneous placement of dental implants. Thirty graftless sinus lifting procedures were performed and 72 dental implants placed in 18 consecutive patients, using the lateral window approach. Clinical and radiological follow-up was conducted throughout the 6-month healing period. Biopsies of 30 cases were collected at 6 months post-treatment: 15 biopsies were taken from the newly formed bone near the basal floor and 15 from the newly formed bone near the elevated membrane. New bone consolidation in the maxillary sinus was apparent radiologically and histologically at 6 months after sinus augmentation, providing an average 6.14±1.34mm of bone-gain. Based on histological analysis and histomorphometric data, the consolidated bone in the augmented sinus comprised 56.7±11.9% to 59.9±13.4% vital bone tissue. Out of the 72 implants placed, only four failed, indicating a 94% overall implant survival rate. Based on this case series, blood clot can be considered autologous osteogenic graft material, to which osteoprogenitors can migrate, differentiate, and regenerate bone.

Eosinophilic granulopoiesis in human fetal liver.

Eosinophilic granulopoiesis was investigated in human fetal liver during intrauterine life from 5 to 34 weeks of gestation. Eosinophilic granulocytes were observable for the first time at 5 weeks in the hepatic laminae and were frequently found in the late embryonic period around the large vessels and in the mesenchyme adjacent to the liver. Eosinophilic granulopoiesis increased gradually in the hepatic laminae (P < 0.01) after 20 weeks of gestation and in the portal areas (P < 0.05) after 16 weeks of gestation. The proportions of each cellular differentiation stage were relatively constant during fetal life, but a greater number of mature eosinophils were observed in the portal areas. Eosinophilic granulopoiesis was evident in all the hepatic tissue components, but developed more actively in portal areas than in hepatic laminae during intrauterine life. Eosinophilic granulopoiesis preceded both erythropoiesis and megakaryopoiesis in the human embryonic liver. Although the latter two occurred mainly in the hepatic laminae, eosinophilic granulopoiesis developed more actively in the portal areas, where it exhibited increasing activity along with the development of the component cells.

Relationship between normal heart size and body indices in Korean.

We provided a curve-fit equation to predict the normal heart weight (g) in Koreans by examining 422 autopsies (215 males and 207 females, from newborn to age 77 yr) who were relatively in good general condition. Heart weight was well correlated with body surface area (m2), body weight (kg), and body height (cm) but poorly with age in both sex. Heart weight progressively increased from birth to the earlier 3rd and 4th decades in male and female, respectively, and then gradually decreased; mean heart weight of all age group was greater in male than in female and significantly different from birth to 4th decade. In both sex, heart weight exponentially increased in accordance with the increase of body height, body weight, and body surface (in male, heart weight=0.00312 x body height(2.239), r2=0.750, p<0.0001; in female, heart weight=0.00443 x body height(2170), r2=0.781, p<0.0001; in male, heart weight=9.22 x body weight(0.853), r2=0.770, p<0.0001; in female, heart weight=9.00 x body weight0.855, r2=0.820, p<0.0001; in male, heart weight=155.18 x body surface area1.290, r=0.808, p<0.0001; in female, heart weight=124.13 x body surface area1.242, r=0.834, p<0.0001). These results indicate that heart weight is better correlated with body surface area than with body weight; however, body weight should be a better determinant of a predicted heart weight, since body surface area is entirely dependent on body height and body weight.