Effects of keratinocyte-derived and fibroblast-derived exosomes on human epidermal melanocytes

Background: Exosomes have been demonstrated to carry proteins, membrane lipids, mRNAs and microRNAs which can be transferred to surrounding cells and regulate the functions of those recipient cells. Objectives: The objective of the study was to investigate the effects of exosomes released by keratinocytes and fibroblasts on the proliferation, tyrosinase activity and melanogenesis of melanocytes. Methods: Melanocytes, keratinocytes and fibroblasts obtained from human foreskin were cultured and exosomes secreted by keratinocytes and fibroblasts were harvested from the culture supernatants by ultracentrifugation. Each exosome fraction was divided into two parts; one part was subjected to high-throughput sequencing using an Illumina HiSeq sequencer to characterize the microRNA expression profiles, while the other part was labeled with the fluorescent dye PKH67 and was then co-cultivated with epidermal melanocytes. Results: High-throughput sequencing analysis showed 168 differentially expressed microRNA within exosomes derived from keratinocytes and from fibroblasts, 97 of those being up-regulated with the other 71 down-regulated. Gene ontology analysis showed that the target genes responsible for these differentially expressed microRNAs were mainly enriched in the protein-binding region of molecular functions. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that target genes regulated by differentially expressed microRNA were mainly involved in mitogen-activated protein kinase (MAPK) signaling pathway, Ras signaling pathway, cAMP signaling pathway and Wnt signaling pathway. Keratinocyte-derived exosomes were taken up by melanocytes co-cultured with them and promoted the proliferation, tyrosinase activity and melanin synthesis of those melanocytes. However, fibroblast-derived exosomes had no similar effects on melanocytes. Conclusion: Keratinocyte-derived exosomes but not fibroblast-derived exosomes were taken up by melanocytes in co-culture and significantly stimulated their proliferation, tyrosinase activity and melanin synthesis. Those different effects may be mainly due to the differential expression of microRNAs in exosomes derived from the different types of cells. Limitations: Electron microscopy of the obtained exosomes and in-depth study of apparently differentially expressed microRNAs were not performed

Gadolinium-enhanced MRI reveals dynamic development of endolymphatic hydrops in Ménières disease / Ressonância magnética com gadolínio revela o desenvolvimento dinâmico da hidropsia endolinfática na doença de Ménière

Abstract Introduction: Meniere's disease is associated with impaired hearing, tinnitus, vertigo, and aural fullness. Many anatomical studies have suggested idiopathic endolymphatic hydrops as the pathological basis of Meniere's disease, which now can be visualized by using gadolinium -enhanced magnetic resonance imaging of the inner ear. Objective: To investigate the development of endolymphatic hydrops in Meniere's disease by monitoring the vestibules and cochleae of affected patients. Methods: Inner ears of 178 patients with definite unilateral Meniere's disease diagnosis were visualized by 3-dimensional fluid-attenuated inversion recovery and three-dimensional real inversion recovery magnetic resonance imaging following bilateral gadolinium intratympanic injection. The scans were used to evaluate the presence and degree of endolymphatic hydrops in the vestibules and cochlear structures, including the cochlear apical turn, the cochlear middle turn, and the cochlear basal turn. The correlation of endolymphatic hydrops occurrence between the various parts of the inner ear was determined. Results: Symptomatic endolymphatic hydrops was detected on the affected side in all patients, whereas asymptomatic endolymphatic hydrops was detected on the unaffected contra-lateral side in 32 patients (18.0%). On the affected side, the cochlear apical turn and the cochlear middle turn demonstrated significantly higher rates of endolymphatic hydrops than the cochlear basal turn and the vestibule. The severity of endolymphatic hydrops gradually decreased from the cochlear apical turn to the cochlear basal turn. On the contra lateral side, the incidence and degree of the detected asymptomatic endolymphatic hydrops were significantly greater in the cochleae than in the vestibules (p < 0.05), with no significant difference detected between the cochlear turns. Conclusion: Progression of endolymphatic hydrops appears to be directional, initiated in the cochlea. The order of endolymphatic hydrops severity gradually decreases from the cochlear apical turn to the cochlear basal turn and then to the vestibule. Endolymphatic hydrops in the vestibule is associated with symptomatic Meniere's disease.

Resumo Introdução: A doença de Ménière está associada a deficiência auditiva, zumbido, vertigem e plenitude auricular. Muitos estudos anatômicos sugerem hidropsia endolinfática idiopática como a base patológica da doença, que agora pode ser visualizada através de estudo por imagem da orelha interna por ressonância magnética com gadolínio. Objetivo: Investigar o desenvolvimento da hidropsia endolinfática na doença de Ménière com monitoramento dos vestíbulos e das cócleas dos pacientes afetados. Métodos: Orelhas internas de 178 pacientes com diagnóstico definitivo de doença de Ménière unilateral foram visualizados através de imagem de recuperação de inversão atenuada por fluidos em ressonância magnética tridimensional, 3-D FLAIR, e por inversão real após injeção intratimpânica bilateral de gadolínio. Os exames foram usados para avaliar a presença e o grau de hidropsia endolinfática nos vestíbulos e nas estruturas cocleares, inclusive o giro coclear apical, o giro coclear médio e o giro coclear basal. A correlação da ocorrência de hidropsia endolinfática entre as várias partes da orelha interna foi determinada. Resultados: Hidropsia endolinfática sintomática foi detectada no lado afetado em todos os pacientes, enquanto hidropsia endolinfática assintomática foi detectada no lado contralateral não afetado em 32 pacientes (18,0%). No lado afetado, o giro apical da cóclea e o giro coclear médio demonstraram taxas significativamente mais altas de hidropsia endolinfática do que o giro basal e o vestíbulo. A gravidade da hidropsia endolinfática diminuiu gradualmente do giro apical da cóclea para o giro basal. No lado contralateral, a incidência e o grau da hidropsia endolinfática assintomática detectada foram significantemente maiores nas cócleas do que nos vestíbulos (p < 0,05), sem diferença significante entre os giros cocleares. Conclusões: A progressão da hidropsia endolinfática parece ser direcional, iniciando-se na cóclea. A sua ordem da gravidade diminui gradualmente do giro apical da cóclea para o giro basal e, em seguida, para o vestíbulo. A hidropsia endolinfática no vestíbulo está associada à doença de Ménière sintomática.

Melanocyte spheroids are formed by repetitive long-term trypsinization

Background: Autologous melanocyte transplantation plays an important role in the treatment of vitiligo. Objective: Previous studies have indicated that, compared with melanocytes growing in monolayers, melanocyte spheroids have a better survival in growth factor- and serum-deprived conditions. Methods: Melanocyte spheroids were obtained from human epidermis by repetitive long-term trypsinization and maintained an aggregated morphology for a short period in certain conditions. Results: Melanocyte spheroids were capable of growing into normal dendritic melanocytes in monolayer when they were harvested and reinoculated in 24-well plates. Immunohistochemical analysis of the melanocyte spheroids revealed that they were positive for HMB45, a melanosome-specific marker. No melanomas occurred when melanocyte spheroids were transplanted into mice. Conclusion: Our study provides a promising approach for melanocyte transplantation to treat vitiligo.

Efficacy and safety of sitagliptin added to metformin and insulin compared with voglibose in patients with newly diagnosed type 2 diabetes

OBJECTIVE: To assess the efficacy and safety of sitagliptin compared with voglibose added to combined metformin and insulin in patients with newly diagnosed type 2 diabetes (T2DM). METHODS: In this 12-week prospective, randomized, parallel trial, 70 newly diagnosed T2DM patients with glycosylated hemoglobin (HbA1c) ≥9% and/or fasting plasma glucose (FPG) ≥11.1 mmol/L were randomized (1:1) to receive sitagliptin 100 mg per day + metformin + insulin glargine or voglibose 0.2 mg three times daily + metformin + insulin glargine. Change in HbA1c at week 12 was the primary endpoint. RESULTS: The mean baseline HbA1c was 11.0% in the patients. The changes in HbA1c from baseline were -6.00% in the sitagliptin group and -3.58% in the voglibose group, and the between-group difference was -2.42% (95% CI -1.91 to -2.93, p=0.02). The differences in FPG and homeostatic model assessment of β-cell function (HOMA-β) and the change in body weight between groups from baseline were -2.95 mmol/L (p=0.04), 43.91 (p=0.01) and -2.23 kg (p=0.01), respectively. One patient (2.9%) in the sitagliptin group and three patients (8.6%) in the voglibose group exhibited hypoglycemia. CONCLUSIONS: Sitagliptin added to combined metformin and insulin therapy showed greater efficacy and good safety regarding hypoglycemia in patients with newly diagnosed T2DM compared with voglibose.

Regulation mechanism of rnc gene on Streptococcus mutans environmental tolerance and its mechanism / 口腔疾病防治

Objective @#To study the changes of acid resistance, oxidation resistance and high osmotic pressure resistance of Streptococcus mutans after knockout of rnc gene and its possible regulatory mechanism.@*Methods@#Through PCR ligation mutagenesis, an rnc knockout mutant (Smurnc) was constructed. Acid tolerance, oxidation tolerance and high osmotic pressure tolerance were compared between Smurnc and the wild strain respectively. Real-time RT-PCR was used to verify the changes in expression of stress tolerance related genes at the transcriptional level.@*Results @#When rnc gene was knocked out, the acid tolerance (χ2=13.464, P=0.001) and oxidation tolerance (χ2=4.505, P=0.048) of Streptococcus mutans was significantly decreased, but the high osmotic pressure tolerance was significantly increased (χ2=11.971, P=0.001). Expression of stress tolerance related genes luxS and ropA (0.64 and 0.51 times expression of the wild strain) had been significantly downregulated (P<0.001). Expression of htrA and brpA (1.56 and 1.80 times expression of the wild strain) had been significantly upregulated (P<0.001).@*Conclusion @#The deletion of rnc gene affects the expression of the environmental tolerance related genes of Streptococcus mutans, which reduces its acid resistance and oxidation resistance, and enhances its tolerance to hypertonic pressure.

Lingual radicular rift valley in a mandibular right first premolar root: report of a rare case and review of the literature / Surco radicular lingual en la raíces del primer premolar mandibular derecho: reporte de un raro caso y revisión de la literatura

Irregular root configurations which often challenge the requirements of successful root canal treatments are always misleading doctors to incorrect clinical judgments and treatment planning. In this article we describe a rare case of CBCT C-shaped mandibular premolar with a huge area of invagination measuring 6 mm ´ 3 mm, which we termed a "radicular rift valley" from a 76-year-old man. Considering the complex process of differential diagnosis, the overall status of disease condition and the will of the patient we proposed five treatment plans and finally conservatively chose plan B composed of both RCT and periapical scaling. A related literature review is also added into this article to describe the whole situation of root invagination, to stress the importance of the vigilance of diagnosis and to provide reference views for future similar diseases.

Las configuraciones radiculares irregulares que a menudo desafían las exigencias de un tratamiento de canal radicular exitoso, son siempre engañosas llevando al especialista a juicios clínicos y planificación de tratamientos erróneos. En este artículo se describe, en un hombre de 76 años de edad, un raro caso de un premolar mandibular que mediante CBCT se observa la forma de C con un área enorme de invaginación midiendo 6 mm x 3 mm, lo que hemos denominado un "Rift valley radicular ". Teniendo en cuenta el complejo proceso de diagnóstico diferencial, el estado general de enfermedad y la voluntad del paciente, se propusieron cinco planes de tratamiento y, finalmente, se eligió el plan B conservador compuesto por el tratamiento del canal radicular y tratamiento periapical. Una revisión de la literatura relacionada se añade en este artículo para describir las situación de invaginación radicular, haciendo hincapié en la importancia del diagnóstico y para proporcionar referencias para enfermedades similares futuras.

Familial progressive hypo- and hyperpigmentation: A variant case.

Familial progressive hyper- and hypopigmentation (FPHH) is characterized by diffuse hyperpigmentation with variable intensity. Cafe'-au-lait macules and larger hypopigmented ash-leaf macules are also present. Herein, we reported a variant case of FPHH. The patient was a two-year-old Chinese girl showing diffuse hyper- and hypopigmented lesions, longitudinal melanonychia in both thumbs, and infantile seizures, without any lentigines.