TpTe and TpTe/QT: novel markers to predict sudden cardiac death in ESRD? / TpTe e TpTe/QT: novos marcadores para prever morte súbita cardíaca na DRT?

ABSTRACT Introduction: Reliable markers to predict sudden cardiac death (SCD) in patients with end stage renal disease (ESRD) remain elusive, but echocardiogram (ECG) parameters may help stratify patients. Given their roles as markers for myocardial dispersion especially in high risk populations such as those with Brugada syndrome, we hypothesized that the Tpeak to Tend (TpTe) interval and TpTe/QT are independent risk factors for SCD in ESRD. Methods: Retrospective chart review was conducted on a cohort of patients with ESRD starting hemodialysis. Patients were US veterans who utilized the Veterans Affairs medical centers for health care. Average age of all participants was 66 years and the majority were males, consistent with a US veteran population. ECGs that were performed within 18 months of dialysis initiation were manually evaluated for TpTe and TpTe/QT. The primary outcomes were SCD and all-cause mortality, and these were assessed up to 5 years following dialysis initiation. Results: After exclusion criteria, 205 patients were identified, of whom 94 had a prolonged TpTe, and 61 had a prolonged TpTe/QT interval (not mutually exclusive). Overall mortality was 70.2% at 5 years and SCD was 15.2%. No significant difference was observed in the primary outcomes when examining TpTe (SCD: prolonged 16.0% vs. normal 14.4%, p=0.73; all-cause mortality: prolonged 55.3% vs. normal 47.7%, p=0.43). Likewise, no significant difference was found for TpTe/QT (SCD: prolonged 15.4% vs. normal 15.0%, p=0.51; all-cause mortality: prolonged 80.7% vs. normal 66.7%, p=0.39). Conclusions: In ESRD patients on hemodialysis, prolonged TpTe or TpTe/QT was not associated with a significant increase in SCD or all-cause mortality.

RESUMO Introdução: Marcadores confiáveis para predizer morte súbita cardíaca (MSC) em pacientes com doença renal terminal (DRT) permanecem elusivos, mas os parâmetros do ecocardiograma (ECG) podem ajudar a estratificar os pacientes. Devido a seus papéis como marcadores para a dispersão miocárdica, especialmente em populações de alto risco, como aquelas com síndrome de Brugada, nós hipotetizamos que o intervalo pico da onda T ao final da onda T (TpTe) e TpTe/QT são fatores de risco independentes para MSC na DRT. Métodos: Revisão retrospectiva do prontuário foi realizada em uma coorte de pacientes com DRT iniciando a hemodiálise. Os pacientes eram veteranos de guerra americanos que utilizavam os centros médicos do Veterans Affairs para atendimento médico. A idade média de todos os participantes foi de 66 anos e a maioria era do sexo masculino, consistente com uma população veterana dos EUA. ECGs que foram realizados dentro de 18 meses após o início da diálise, e foram avaliados manualmente para TpTe e TpTe/QT. Os desfechos primários foram MSC e mortalidade por todas as causas, e estes foram avaliados até 5 anos após o início da diálise. Resultados: Após o critério de exclusão, foram identificados 205 pacientes, dos quais 94 com TpTe prolongado e 61 com intervalo TpTe/QT prolongado (não mutuamente exclusivo). A mortalidade geral foi de 70,2% em 5 anos e a MSC foi de 15,2%. Nenhuma diferença significativa foi observada nos desfechos primários ao se avaliar o TpTe (MSC: prolongado 16,0% versus normal 14,4%, p = 0,73; mortalidade por todas as causas: prolongado 55,3% vs. normal 47,7%, p = 0,43). Da mesma forma, nenhuma diferença significativa foi encontrada para TpTe/QT (MSC: prolongado 15,4% vs. normal 15,0%, p = 0,51; mortalidade por todas as causas: prolongado 80,7% vs. normal 66,7%, p = 0,39). Conclusões: Em pacientes com insuficiência renal terminal em hemodiálise, TpTe ou TpTe/QT prolongados não foram associados a um aumento significativo da morte súbita ou mortalidade por todas as causas.

Comparative study of scientific publications in orthopedics journals originating from USA, Japan and China (2000-2012)

PURPOSE: To compare orthopedics publications from USA, Japan and China. METHODS: Scientific papers belong to ''Orthopedics'' category of Science Citation Index Expanded subject categories were retrieved from the "PubMed'' and ''Web of Knowledge'' online databases. RESULTS: In the field of orthopedics, the annual number increased significantly from 2000 to 2012 in the three countries (p<0.001). The share of articles increased significantly in China, but decreased significantly in Japan and USA (p<0.05). In 2012, USA contributed 35.3% of the total world output in orthopedics field and ranked 1st; Japan contributed 5.9% and ranked 4th; China contributed 5.2% and ranked 5th. Publications from USA had the highest accumulated IFs and the highest total citations of articles (USA > Japan > China, p<0.001). Average IF from USA was much higher than Japan and China (p<0.001). USA published the most articles in the top ten orthopedics journals (USA (14355) > Japan (1702) > China (487), p<0.01). CONCLUSION: Although China has undergone significant increase in annual number and percentage of scientific publication in orthopedics journals, it still lags far behind USA and Japan in the field of orthopedics in terms of quantity and quality.

Differentiation of human bone marrow precursor cells into neuronal-like cells after transplantation into canine spinal cord organotypic slice cultures / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Treatments to regenerate different tissue involving the transplantation of bone marrow derived mesenchymal precursor cells are anticipated. Using an alternative methods, in vitro organotypic slice culture method, would be useful to transplant cells and assessing the effects. This study was to determine the possibility of differentiating human bone marrow precursor cells into cells of the neuronal lineage by transplanting into canine spinal cord organotypic slice cultures.</p><p><b>METHODS</b>Bone marrow aspirates were obtained from posterior superior iliac spine (PSIS) of patients that had undergone spinal fusion due to a degenerative spinal disorder. For cell imaging, mesenchymal precursor cells (MPCs) were pre-stained with PKH-26 just before transplantation to canine spinal cord slices. Canine spinal cord tissues were obtained from three adult beagle dogs. Spinal cords were cut into transverse slices of 1 mm using tissue chopper. Two slices were transferred into 6-well plate containing 3 ml DMEM with antibiotics. Prepared MPCs (1×10(4)) were transplanted into spinal cord slices. On days 0, 3, 7, 14, MPCs were observed for morphological changes and expression of neuronal markers through immunofluorescence and reverse transcription-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>The morphological study showed: spherical cells in the control and experiment groups on day 0; and on day 3, cells in the control group had one or two thick, short processes and ones in the experiment group had three or four thin, long processes. On day 7, these variously-sized processes contacted each other in the experiment group, but showed typical spindle-shaped cells in the control group. Immunofluorescence showed that PKH-26(+) MPCs stained positive for NeuN(+) and GFAP(+) in experimental group only. Also RT-PCR showed weak expression of β-tubulin III and GFAP.</p><p><b>CONCLUSIONS</b>Human bone marrow mesenchymal precursor cells (hMPCs) have the potential to differentiate into the neuronal like cells in this canine spinal cord organotypic slice culture model. Furthermore, these findings suggested the possibility that these cells can be utilized to treat patients with spinal cord injuries.</p>

Age-related degeneration of each lumbar intervertebral disc in symptomatic patients:MRI analysis / 中国脊柱脊髓杂志

Objective:To determine the most common patterns in symptomatic lumbar intervertibral disc degeneration at various age period.Method:The lumbar MRI imaging data of 529 patients treated for low back pain with or without skelagia in Santa Monica hospital in USA from 2004 to 2006 were reviewed retrospectively in this study .There were 191 females, 338 males.Degenerative grading was made for all disc levels in the lumbar spine for each patient. The patients were also classified into five age different groups starting from below age 30,with the intervals of a single decade,until over age 60 (≤29 years,30-39 years,40-49 years, 50-59 years and≥60 years).The degenerative grade of all disc levels (L1/2 to L5/S1) in each patient was classified based on Pfirrmann's gading system,and locations and the progressive manner of the degeneration were determined for age groups.SPSS software version 13.0 (SPSS Inc.,Chicago,IL) on a personal computer was used for statistical analyses.Result:The most common pattern in all ages is normal in all the discs and it is described as 1-1-1-1-1 and this normal pattern was found in 71 patients (13.4%).There was rare change to develop severe degeneration (grade 4) for low age groups.The upper levels of the lumbar spine had more commonly lower degenerative grades,and the lower levels had relatively higher grades of advanced disc de-generation.In the age groups of below 29 years and 30-39 years,the most common pattern was normal in all the discs of 5 levels as 1-1-1-1-1.And this pattern was more prominent in the age group below 29 years.In the age group of 40-49 years.it was changed to single level L5-S1 degeneration with 1-1-1-1-3(7.6%) butthe normal discs in all levels had also a similar portion(6.8%).In the age groups of 50-59 years and over 60 years,it was changed to the pattern with all discs abnormal as 3-3-3-3-3.Single level involvement was negatively correlated with age (P<0.01 ).On the contrary,whole symmetrical degenerative involvement of all levels was positively correlated with age (P<0.01).Single L5/S1 involvement was most common in the age group of below 29 years,but in the age group of 30-39 years,the most common pattern was changed to L4/5 and L5/ S1 double involvement(P< 0.05).A relative small portion appeared as the most common pattern with less than two-level involvement in the age groups over 50 years.Conclusion:The rate of unilevel degenerative pattern of lumbar spine in overall population decreases with the progression of age, while that of all-level degenerative pattern increases with the progression of age.