QT dispersion correlates with systolic rather than diastolic parameters in patients receiving anthracycline treatment

OBJECTIVE: The aim of this study was to investigate the relation of QT dispersion to left ventricular (LV) systolic and diastolic function in patients undergoing anthracycline therapy. METHODS: We used echocardiography to evaluate LV systolic and diastolic function and electrocardiography to evaluate QT dispersion and corrected QT dispersion (QTcD) in patients with hematological diseases, who received anthracycline therapy. PATIENTS: Seventy-two patients with hematological diseases who were receiving anthracycline treatment were enrolled in the present study. RESULTS: LV end-diastolic diameter or LV end-systolic diameter had a significant positive correlation to QTcD (r = 0.35, p < 0.01, r = 0.43, p < 0.01). Also left ventricular ejection fraction of (LVEF) or fractional shortening had a significant negative correlation to QTcD (r = -0.46, p < 0.001, r = -0.27, p = 0.02). The highest QTcD group had a significantly larger LV end-diastolic diameter or LV end-systolic diameter than the lowest QTcD [48.5 +/- 5.7 vs. 44.4 +/- 4.5 (mm), p < 0.001, 34.1 +/- 6.4 vs. 28.8 +/- 4.3 (mm), p < 0.001] and the highest QTcD group had a significantly lower LVEF than the lowest QTcD [57.5 +/- 8.0 vs. 65.5 +/- 6.4 (%), p < 0.001]. On the other hand, none of the diastolic function markers were significantly correlated with QTcD. CONCLUSION: We concluded that increased QTcD is correlated with LV dilation and systolic dysfunction induced by anthracycline therapy, and does not reflect a dispersion of ventricular repolarization or asynchronous motion.     

Insecticide resistance in potential vector mosquitoes for West Nile virus in Japan

Culex pipiens complex is the significant vector mosquito of West Nile virus. To take stock of the current situation of insecticide susceptibilities and design an ideal mosquito control strategy, we collected Culex pipiens pallens Coquillet, Culex pipiens form molestus Forskal, and Culex quinquefasciatus Say from fields in Japan and conducted bioassays for five larvicides (fenitrothion, temephos, etofenprox, diflubenzuron, and pyriproxyfen) by using a larval dipping method. Among five insecticides tested, obvious reduced susceptibilities were observed for etofenprox, which is the only pyrethroid compound registered as a larvicide in Japan. Twenty-two of 56 colonies exhibited a >10% survival rate at the etofenprox concentration of 5.7 microg/ml, which is a 10 times higher concentration of the working solution. The LC50 of a colony collected from Fukuoka prefecture for etofenprox exceeded 60 microg/ml (resistance ratio >2,307), and this colony also exhibited cross-resistance to other pyrethroids, permethrin (299-fold) and phenothrin (1,200-fold). The insect growth regulators diflubenzuron and pyriproxyfen were found to be sufficiently effective enough to control Culex larvae present, but decreased sensitivities to these insecticides were slightly detected in some colonies of Cx. p. form molestus collected from urban areas. Several etofenprox-resistant colonies of Cx. p. form molestus exhibited simultaneously decreased susceptibilities to other insecticides, including temephos, diflubenzuron, and pyriproxyfen.     

Pathology and sensitivity of current clinical criteria in corticobasal syndrome

The aim of this study was to investigate corticobasal syndrome with respect to underlying pathologies, the ability of current clinical criteria to detect early stages of disease, and symptoms and signs predicting background pathologies. We retrospectively analyzed the clinicopathological findings from patients with corticobasal syndrome. We also analyzed whether those findings fulfilled the diagnostic criteria for corticobasal degeneration (CBD). Finally, we investigated characteristic clinical features that are specific to each background pathology. Of 10 consecutive autopsied patients who had corticobasal syndrome (mean age ± standard deviation, 67.9 ± 9.3 years; male:female ratio, 6:4), three had corticobasal degeneration pathology, three had progressive supranuclear palsy, three had Alzheimer's disease, and one had atypical four‐repeat tauopathy. Nine patients fulfilled Mayo criteria, and all 10 patients fulfilled modified Cambridge criteria at the later stage, but only two patients fulfilled either clinical criteria within 2 years of disease onset. Five patients fulfilled the clinical criteria for possible CBD (p‐CBD), and one patient fulfilled the clinical research criteria for probable sporadic CBD (cr‐CBD) at the later stage. Only two patients fulfilled the criteria for either p‐CBD or cr‐CBD within 2 years of disease onset. Although we could not find any predictive characteristic clinical features that were specific to CBD pathology, only patients with progressive supranuclear palsy developed apraxia of eyelid opening and cerebellar ataxia. Myoclonus and memory impairment, especially if they appear at an early stage of the disease, may predict Alzheimer's disease pathology. Sensitivity of the available clinical criteria for corticobasal syndrome was poor within 2 years of disease onset. © 2013 International Parkinson and Movement Disorder Society     

Analysis of malaria endemic areas on the Indochina Peninsula using remote sensing

We applied remote sensing using satellite images capable of obtaining data over a broad range, transcending national borders, as a method of rapidly, precisely, and safely increasing our understanding of the potential distribution of malaria. Our target region was the so-called Mekong malaria region on the Indochina Peninsula. As a malaria index, we used existing distribution maps of total reported malaria cases, malaria mortality, vivax malaria and falciparum malaria incidences, and so forth for 1997 and 1998. We produced monthly distribution maps of a normalized difference vegetation index (NDVI) with values of 0.2+, 0.3+, 0.35+, and 0.4+ using the geographical information system/remote sensing software based on the East Asia monthly NDVI maps of 1997. These maps were overlaid with various malaria index distribution maps, and cross-tabulations were carried out. The resulting maps with NDVI values of 0.3+ and 0.4+ matched the falciparum malaria distribution well, and we realized, in particular, that falciparum malaria is prevalent in regions in which NDVI values of 0.4+ continue for 6 months or more, while cases are fewer in regions with NDVI values of 0.4+ that continue for 5 months or less. It will be necessary in the future to examine the relationship between NDVI values and the habitats of the various vector mosquitoes using high-resolution satellite images and to implement detailed forecasts for malaria endemic areas by means of NDVI.