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BACKGROUND CONTEXT
It is widely recognized that sagittal spinal alignment changes with age. However, there are presently no clear benchmarks for such values or those for the cervical spine in the general population. Quality epidemiological studies are needed to establish standards for spinal alignment deviation.OBJECTIVES
In this study of an aged Japanese population, we employed random sampling from the basic resident registry of a rural town for subject selection to determine reference values of sagittal spinal alignment including the cervical spine.STUDY DESIGN
Japanese resident cohort study based on a municipal registry.PATIENT SAMPLE
A total of 413 aged people randomly sampled from the resident registry of a rural Japanese town.OUTCOME MEASURES
All subjects underwent a whole spine lateral radiograph for measurement of sagittal spinal alignment parameters.METHODS
Registered citizens of 50 to 89 years old were targeted for this survey. We established eight groups based on age (50s, 60s, 70s, and 80s) and gender (male and female) after random sampling from the resident registry of Obuse town in 2014. A total of 413 people (203 males and 210 females) were enrolled. Radiographic parameters of sagittal spinal alignment of the cohort were measured and analyzed. Funding for this study was provided by the Japan Orthopaedics and Traumatology Research Foundation (10,000 USD), the Japanese Orthopaedic Association (5,000 USD), the Japanese Society for Musculoskeletal Medicine (40,000 USD), and the Nakatomi Foundation (15,000 USD).RESULTS
Global spinal alignments became more misaligned with age for both genders. Sagittal vertical axis (SVA) forward shift was significantly more frequent in 80s males and 70s females, and SVA in 80s females was a mean of 66 mm forward of that of 50s females. Cervical protrusion was markedly greater in 60s males onwards. In women, lumbar lordosis and posterior pelvic inclination were noticeable from a younger age than in men. The amount of pelvic tilt misalignment in female subjects was approximately 10 years earlier than their male counterparts.CONCLUSIONS
This first resident cohort of Japanese individuals determined average spinal alignment parameters by age and gender. Spinal balance generally shifts forward as age increases. A forward shift in the upper cervical spine occurs first in men, whereas lumbopelvic alignment shift occurs first in women. 相似文献- FFR/iFR is discordant in 15–20% of cases, at times causing confusion about revascularization decisions.
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Areas covered: LB80380 is a prodrug of LB80331 and LB80317. It is rapidly absorbed when taken orally. Escalating doses of besifovir produce linear increase of the plasma concentration. Doses above 60mg are effective for inhibiting HBV in human. Using 60mg as an example, the maximal concentration of LB80331 in plasma is 397 ng/mL. The time required to reach maximal concentration in plasma and elimination half-life are 2.0 and 3.0 h, respectively. Besifovir and its metabolites are mainly excreted via the kidneys. Its antiviral efficacy is non-inferior to ETV 0.5mg daily. It is generally safe in terms of renal and bone toxicity. The most common adverse event is carnitine depletion which affects almost all patients on besifovir requiring carnitine supplementation.
Expert opinion: Besifovir demonstrated predictable pharmacokinetic characteristics in human subjects. Few clinical studies on besifovir have been conducted. More data are expected particularly for special populations. The adverse events upon long term exposure should be monitored. Large scale head-to-head trials comparing besifovir with existing NA, especially tenofovir alafenamide, should be conducted. 相似文献