The dynamics of epidemiology and impact on the control of diseases: a review.

This paper describes the relationship between epidemiology and other desciplines including medical and social sciences both of which are expanding in scope. As a discipline, epidemiology is not only growing in scope as well but also developing new techniques of establishing facts about disease causation and interventions demonstrating how prevention programmes could be carried out for the benefit of communities from the burden of disease. Further, the effects of epidemiological findings in the developed North on the control of diseases and the lack of this in the poor South is described. The need for interdisciplinary approach in finding disease prevention solutions is emphasized.     

Regulation of the type I IFN induction: a current view

The type I IFN-alpha/beta gene family was identified about a quarter of a century ago as a prototype of many cytokine gene families, which led to the subsequent burst of studies on molecular mechanisms underlying cytokine gene expression and signaling. Although originally discovered for their activity to confer an antiviral state on cells, more evidence has recently been emerging regarding IFN-alpha/beta actions on cell growth, differentiation and many immunoregulatory activities, which are of even greater fundamental biological significance. Indeed, much attention has recently been focused on the induction and function of the IFN-alpha/beta system regulated by Toll-like receptors (TLRs), which are critical for linking the innate and adaptive immunities. The understanding of the regulatory mechanisms of IFN-alpha/beta gene induction by TLRs and viruses is an emerging theme, for which much new insight has been gained over the past few years.     

Morphometric analysis of the thoracic and lumbar spine in Japanese on the use of pedicle screws

The pedicle screw and hook have become popular instruments in treating spinal deformity and disease. This study gathered morphological data on thoracic and lumbar spines in a Japanese population that should serve as useful reference for posterior instrumentation surgery. One hundred and three dry bones were used to investigate the morphology of pedicle and facet in thoracic and lumbar spines. Measurements included the diameter and axial length of pedicle from T8 to L5, height and width of facets and thickness of articular processes from T1 to T12, and axial angle of pedicle from T1 to L5. The diameter and axial length of pedicle were smallest at T8, diameter was largest at L5 and axial length was largest at L3. Height of facets and thickness of articular processes were largest at T12. Men tended to have larger pedicles and facets than women. Transverse angle of pedicle was smallest at T12. These precise data may provide useful information when performing posterior instrumentation surgery and when developing new spinal implant systems for Asians.     

Association between Vitamin D and Heart Failure Mortality in 10,974 Hospitalized Individuals

A broad range of chronic conditions, including heart failure (HF), have been associated with vitamin D deficiency. Existing clinical trials involving vitamin D supplementation in chronic HF patients have been inconclusive. We sought to evaluate the outcomes of patients with vitamin D supplementation, compared with a matched cohort using real-world big data of HF hospitalization. This study was based on the Diagnosis Procedure Combination database in the Japanese Registry of All Cardiac and Vascular Datasets (JROAD-DPC). After exclusion criteria, we identified 93,692 patients who were first hospitalized with HF between April 2012 and March 2017 (mean age was 79 ± 12 years, and 52.2% were male). Propensity score (PS) was estimated with logistic regression model, with vitamin D supplementation as the dependent variable and clinically relevant covariates. On PS-matched analysis with 10,974 patients, patients with vitamin D supplementation had lower total in-hospital mortality (6.5 vs. 9.4%, odds ratio: 0.67, p < 0.001) and in-hospital mortality within 7 days and 30 days (0.9 vs. 2.5%, OR, 0.34, and 3.8 vs. 6.5%, OR: 0.56, both p < 0.001). In the sub-group analysis, mortalities in patients with age < 75, diabetes, dyslipidemia, atrial arrhythmia, cancer, renin-angiotensin system blocker, and β-blocker were not affected by vitamin D supplementation. Patients with vitamin D supplementation had a lower in-hospital mortality for HF than patients without vitamin D supplementation in the propensity matched cohort. The identification of specific clinical characteristics in patients benefitting from vitamin D may be useful for determining targets of future randomized control trials.     

Improvement of brain single photon emission tomography (SPET) using transmission data acquisition in a four-head SPET scanner

Attenuation coefficient maps (-maps) are a useful way to compensate for non-uniform attenuation when performing single photon emission tomography (SPET). A new method was developed to record single photon transmission data and a-map for the brain was produced using a four-head SPET scanner. Transmission data were acquired by a gamma camera opposite to a flood radioactive source attached to one of four gamma cameras in the four-head SPET scanner. Attenuation correction was performed using the iterative expectation maximization algorithm and the-map. Phantom studies demonstrated that this method could reconstruct the distribution of radioactivity more accurately than conventional methods, even for a severely non-uniform-map, and could improve the quality of SPET images. Clinical application to technetium-99m hexamethylpropylene amine oxime (HMPAO) brain SPET also demonstrated the usefulness of this method. Thus, this method appears to be promising for improvement in the image quality and quantitative accuracy of brain SPET.This work was presented in part at the World Congress on Medical Physics and Biomedical Engineering, 7–12 July 1991, Kyoto, Japan     

Double-injection method for sequentially measuring cerebral blood flow with N-isopropyl-(123I)p-iodoamphetamine

We investigated the accuracy of a double-injection method for sequentially measuring cerebral blood flow (CBF) with N-isopropyl-(123I)p-iodoamphetamine (IMP) in simulation studies based on patient data and in clinical studies. The unidirectional clearance of IMP from the blood to the brain (K1; nearly equal to CBF) in the first and second sessions was calculated by means of a microsphere model. The K1 values in the first session (K1I) were calculated from Cb(5)/Int_CaI, where Cb(5) and Int_CaI are values for brain radioactivity 5 min after the first injection and for arterial blood radioactivity obtained by 5-min continuous sampling. The K1 values in the second session (K1II) were calculated by means of the following four methods. Method 1: [Cb(tz + 5) - Cb(tz)]/[Int_CaII - Ca(tz) x 5], where Cb(tz+5) and Cb(tz) are the brain radioactivity levels 5 min after the second injection and at the time the second session was started (tz), respectively. Int_CaII and Ca(tz) are the arterial blood radioactivity levels obtained by 5-min continuous sampling after the second injection and at tz, respectively. Method 2: [Cb(tz + 5) - Cb(tz)]/[Int_CaI x R], where R is the injection dose ratio. Method 3: [Cb(tz + 5) - Cb(tz) x exp(- K1I x 5/lambda)]/Int_CaII, where lambda is the population averaged partition coefficient. Method 4: same as Method 3 except that K1I was replaced by K1II obtained by means of Method 2. Theoretically, Method 4 appeared to be the best of the four methods. The change in K1 during the second session obtained by Method 1 or 2 largely depended on R and tz, whereas Method 3 or 4 yielded a more reliable estimate than Method 1 or 2, without largely depending on R and tz. Since Method 2 was somewhat superior to other methods in terms of noninvasiveness and simplicity, it also had the potential for routine clinical use. The reproducibility of two sequential measurements of K1 was investigated with clinical data obtained without any intervention. The response of CBF to acetazolamide challenge was also assessed by the above four methods. The knowledge gained by this study may assist in selecting a method for sequentially measuring CBF with a double injection of IMP.