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10.
PLoS One ; 9(10): e109881, 2014.
Article in English | MEDLINE | ID: mdl-25279817

ABSTRACT

Since fallen trees are a key factor in biodiversity and biogeochemical cycling, information about their spatial distribution is of use in determining species distribution and nutrient and carbon cycling in forest ecosystems. Ground-based surveys are both time consuming and labour intensive. Remote-sensing technology can reduce these costs. Here, we used high-spatial-resolution aerial photographs (0.5-1.0 cm per pixel) taken from an unmanned aerial vehicle (UAV) to survey fallen trees in a deciduous broadleaved forest in eastern Japan. In nine sub-plots we found a total of 44 fallen trees by ground survey. From the aerial photographs, we identified 80% to 90% of fallen trees that were >30 cm in diameter or >10 m in length, but missed many that were narrower or shorter. This failure may be due to the similarity of fallen trees to trunks and branches of standing trees or masking by standing trees. Views of the same point from different angles may improve the detection rate because they would provide more opportunity to detect fallen trees hidden by standing trees. Our results suggest that UAV surveys will make it possible to monitor the spatial and temporal variations in forest structure and function at lower cost.


Subject(s)
Aircraft , Data Collection/methods , Environmental Monitoring , Forests , Remote Sensing Technology , Trees , Biodiversity , Ecosystem , Plant Leaves
11.
Ther Clin Risk Manag ; 9: 171-6, 2013.
Article in English | MEDLINE | ID: mdl-23637537

ABSTRACT

PURPOSE: Vitamin D supplementation is suggested to reduce the risk of falls in older institutionalized or ambulatory individuals by 20%. The present study was undertaken to address the reduced risk, by vitamin D supplementation, of falls and hip fractures in patients with vascular Parkinsonism (VP) and Parkinson's disease (PD). PATIENTS AND METHODS: In the open-label-study, 94 elderly patients with VP and 92 age-matched patients with PD were followed for 2 years. All patients received 1200 IU ergocalciferol daily. The number of falls per person and incidence of hip fractures were compared between the two groups. RESULTS: At baseline, serum 25-hydroxyvitamin D (25-OHD) levels were in the deficient range (<25 nmol/L) in all patients, and vitamin D treatment enhanced serum 25-OHD and 1,25-dihydroxyvitamin D levels in both groups. Improved muscle strength of lower extremities was observed in both groups. There was significant difference between the two groups in the number of falls per subject during the 2 years (1.9 ± 0.5 in the PD group and 0.8 ± 0.4 in the VP group, P < 0.001). Hip fractures occurred in seven of 88 in the PD group and one in 90 of the VP group during the 2-year study period (P = 0.035). CONCLUSION: It is suggested that vitamin D decreases falls and hip fractures in VP by increasing muscle strength but not in PD.

12.
J Neurol Neurosurg Psychiatry ; 82(12): 1390-3, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21825080

ABSTRACT

BACKGROUND: Incidence of a fracture, particularly in the hip joint, is high in Parkinson's disease (PD), owing to the immobilisation-induced bone resorption and vitamin D deficiency with reduced bone mineral density (BMD). The authors previously demonstrated the lowered incidence of hip fractures in PD by daily administration of risedronate and vitamin D. METHODS: This randomised, double-blind, placebo-controlled study was conducted to determine the efficacy of 17.5 mg once-weekly risedronate in the prevention of hip fracture in women with PD. Patients were randomly assigned to 17.5 mg risedronate once a week (n=136) or a placebo (n=136) combined with daily 1000 IU of ergocalciferol. Incidence of hip fractures was compared between the two groups during the 2-year follow-up. RESULTS: Hip fractures occurred in 15 patients in the placebo group and 3 patients in the risedronate group. The RR for hip fractures in the risedronate group as compared with the placebo group was 0.20 (95% CI 0.06 to 0.66). In the risedronate group, serum calcium levels decreased during the follow-up, while the levels in the placebo group increased. BMD increased by 3.4% in the risedronate group and decreased by 3.2% in the placebo group (p<0.01). CONCLUSIONS: Treatment with once-weekly risedronate and ergocalciferol prevents hip fractures in older women with PD.


Subject(s)
Bone Density Conservation Agents/therapeutic use , Etidronic Acid/analogs & derivatives , Hip Fractures/drug therapy , Hip Fractures/prevention & control , Parkinson Disease/drug therapy , Aged , Aged, 80 and over , Bone Density/drug effects , Bone Density Conservation Agents/administration & dosage , Calcium/blood , Drug Administration Schedule , Drug Therapy, Combination/adverse effects , Drug Therapy, Combination/methods , Ergocalciferols/administration & dosage , Ergocalciferols/therapeutic use , Etidronic Acid/administration & dosage , Etidronic Acid/therapeutic use , Female , Hip Fractures/blood , Hip Fractures/complications , Humans , Parkinson Disease/blood , Parkinson Disease/complications , Risedronic Acid
13.
Kurume Med J ; 57(4): 117-24, 2011.
Article in English | MEDLINE | ID: mdl-21778673

ABSTRACT

A high incidence of fractures, particularly of the hip, represents an important problem in patients with Alzheimer disease (AD), who are prone to falls and have osteoporosis. We previously found that vitamin K deficiency and low 25-hydroxyvitamin D (25-OHD) with compensatory hyperparathyroidism cause reduced bone mineral density (BMD) in female patients with AD. This may modifiable by intervention with menatetrenone (vitamin K2) and risedronate sodium; we address the possibility that treatment with menatetrenone, risedronate and calcium may reduce the incidence of nonvertebral fractures in elderly patients with AD. A total of 231 elderly patients with AD were randomly assigned to daily treatment with 45 mg of menatetrenone or a placebo combined with once weekly risedronate sodium, and followed up for 12 months. At baseline, patients of both groups showed high undercarboxylated osteocalcin (ucOC) and low 25-OHD insufficiency with compensatory hyperparathyroidism. During the study period, BMD in the treatment group increased by 5.7% and increased by 2.1% in the control group. Nonvertebral fractures occurred in 15 patients (10 hip fractures) in the control group and 5 patients (2 hip fractures) in the treatment group. The relative risk in the treatment group compared with the control group was 0.31 (95% confidence interval, 0.12-0.81). Elderly AD patients with hypovitaminosis K and D are at increased risk for hip fracture. The study medications were well tolerated with relatively few adverse events and effective in reducing the risk of a fracture in elderly patients with AD.


Subject(s)
Alzheimer Disease/complications , Etidronic Acid/analogs & derivatives , Hip Fractures/prevention & control , Osteoporosis/complications , Vitamin D/analogs & derivatives , Vitamin K 2/analogs & derivatives , Aged , Aged, 80 and over , Bone Density , Bone Density Conservation Agents/pharmacology , Etidronic Acid/therapeutic use , Female , Hemostatics/pharmacology , Humans , Hyperparathyroidism/pathology , Male , Osteoporosis/prevention & control , Risedronic Acid , Vitamin D/blood , Vitamin K/metabolism , Vitamin K 2/therapeutic use
14.
Am J Phys Med Rehabil ; 90(4): 281-6, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21273899

ABSTRACT

OBJECTIVE: To determine the pathogenesis of the stooped posture in Parkinson disease (PD), we prospectively studied fractures in a cohort of patients with Parkinson disease for 5 yrs. DESIGN: At baseline, we recorded the dietary intake of vitamin D and serum concentrations of parathyroid hormone and 25-hydroxyvitamin D. Bone mineral density and lateral thoracic and lumbar spine radiographs were obtained at baseline and every year for 5 yrs. RESULTS: During the 5-yr study period, stooped posture developed in 34 patients; the rest of the 58 patients did not show stooped posture. At baseline, mean serum 25-hydroxyvitamin D and parathyroid hormone levels were 10.9 ng/ml and 73.1 pg/ml, respectively, in the stooped group and 18.6 ng/ml and 56.4 pg/ml, respectively, in the nonstooped group. Bone mineral density in the stooped group was significantly lower than in the nonstooped group. Dietary intake of vitamin D in the stooped group was significantly lower than in the nonstooped group. During the study period, 19 (22%) patients in the nonstooped group developed new vertebral fracture, compared with 23 (100%) patients in the stooped group. The mean ± SD percentage changes in bone mineral density were -6.5 ± 0.6 in the stooped group and -3.8 ± 0.8 in the nonstooped group. Mean serum levels of 25-hydroxyvitamin D after 5 yrs were 7.0 ng/ml in the stooped group and 14.1 ng/ml in the nonstooped group. CONCLUSIONS: Stooped posture in Parkinson disease may be caused by vertebral fractures resulting from vitamin D deficiency with compensatory hyperparathyroidism. Vitamin D supplementation may reduce stooped posture in patients with Parkinson disease.


Subject(s)
Lumbar Vertebrae/injuries , Parkinson Disease/pathology , Posture , Spinal Fractures/etiology , Thoracic Vertebrae/injuries , Vitamin D Deficiency/complications , Aged , Bone Density , Cohort Studies , Female , Humans , Male , Middle Aged , Parathyroid Hormone/metabolism , Parkinson Disease/complications , Parkinson Disease/metabolism , Spinal Fractures/metabolism , Spinal Fractures/pathology , Vitamin D/analogs & derivatives , Vitamin D/metabolism , Vitamin D Deficiency/metabolism , Vitamin D Deficiency/pathology
15.
Parkinsonism Relat Disord ; 17(1): 22-6, 2011 01.
Article in English | MEDLINE | ID: mdl-21050796

ABSTRACT

A high incidence of fractures, particularly of the hip, represents an important problem in patients with Parkinson's disease (PD), who are prone to falls and have osteoporosis. We previously showed that 25-hydroxyvitamin D (25-OHD) deficiency due to sunlight deprivation with compensatory hyperparathyroidism causes reduced bone mineral density (BMD) in elderly patients with PD. The present study was undertaken to address the possibility that sunlight exposure may maintain BMD and reduce the incidence of hip fracture in elderly patients with PD. In a prospective study, PD patients were assigned to regular sunlight exposure (n=162) or usual lifestyle (n=162), and followed for 2 years. BMD of the second metacarpal bone was measured using a computed X-ray densitometer. Incidence of hip fracture in the two patient groups during the 2 year follow-up period was assessed. At baseline, patients of both groups showed vitamin D deficiency due to sunlight deprivation with compensatory hyperparathyroidism. The exposed group patients were exposed to sunlight (3231 min/year). BMD increased by 3.8% in the sunlight-exposed group and decreased by 2.6% in the usual lifestyle group (p<.0001). Serum 25-OHD level increased from 27 nmol/L to 52 nmol/L in the sunlight-exposed group. Eleven patients sustained hip fracture in the normal lifestyle group, and 3 fractures occurred among the sunlight-exposed group (p=.03; odds ratio=2.4). Sunlight exposure can increase the BMD of vitamin D deficient bone by increasing 25-OHD concentration and leads to the prevention of hip fracture.


Subject(s)
Osteoporosis/etiology , Osteoporosis/therapy , Parkinson Disease/complications , Parkinson Disease/therapy , Sunlight , Vitamin D Deficiency/etiology , Vitamin D Deficiency/therapy , Absorptiometry, Photon , Aged , Bone and Bones/chemistry , Bone and Bones/metabolism , Diet , Female , Follow-Up Studies , Hip Fractures/epidemiology , Humans , Male , Muscle Strength/physiology , Risk Reduction Behavior , Vitamin D/blood
16.
J Stroke Cerebrovasc Dis ; 20(1): 41-46, 2011.
Article in English | MEDLINE | ID: mdl-20598577

ABSTRACT

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief due to include issues around study governance (ethical oversight and funding), implausible participant recruitment, implausible study conduct and publication timelines, authorship misconduct, conflicting statements about randomization methodology, implausibly similar randomized groups, implausible results, impossible results, duplicate reporting and data errors. In addition, several other publications reporting non-randomized research by members of this group of investigators have been retracted.


Subject(s)
Accidental Falls/prevention & control , Alendronate/therapeutic use , Bone Density Conservation Agents/therapeutic use , Disabled Persons/statistics & numerical data , Hip Fractures/prevention & control , Hydroxycholecalciferols/therapeutic use , Stroke/complications , Aged , Bone Density , Bone and Bones/metabolism , Bone and Bones/pathology , Calcitriol/blood , Female , Humans , Male
17.
J Stroke Cerebrovasc Dis ; 19(3): 198-203, 2010 05.
Article in English | MEDLINE | ID: mdl-20434046

ABSTRACT

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief due to data fabrication, systematic authorship misconduct, text duplication, concerns about data integrity, and scientific misconduct. In addition, several publications reporting non-randomized research by members of this group of investigators have been retracted.


Subject(s)
Bone Density Conservation Agents/therapeutic use , Disabled Persons , Etidronic Acid/therapeutic use , Osteoporosis/prevention & control , Stroke/complications , Aged , Body Mass Index , Bone Density/drug effects , Bone Density Conservation Agents/adverse effects , Calcium/metabolism , Chronic Disease , Disease Progression , Double-Blind Method , Etidronic Acid/adverse effects , Female , Hip Fractures/epidemiology , Hip Fractures/prevention & control , Hospitalization , Humans , Male , Osteoporosis/complications , Parathyroid Hormone/blood , Sunlight , Vitamin D/metabolism
18.
Cerebrovasc Dis ; 29(1): 73-8, 2010.
Article in English | MEDLINE | ID: mdl-19907166

ABSTRACT

Warfarin therapy has been demonstrated to reduce the risk of stroke in nonrheumatic atrial fibrillation (NRAF). We showed that long-term warfarin therapy reduces vitamin K and second metacarpal bone mineral density (BMD) in NRAF patients who had previous hemispheric infarction. To determine whether warfarin is associated with increased hip fracture risk, we compared the incidence of hip fracture between post-stroke patients receiving warfarin therapy and post-stroke patients without such therapy. Eighty-four post-stroke patients with NRAF who had been treated with warfarin and 93 post-stroke patients without warfarin were followed for 5 years and their incidence of hip fracture was compared. At baseline and 3 and 5 years later, sera were collected from both groups. Sera were assayed for undercarboxylated osteocalcin (ucOC), bone Gla protein and 25-hydroxyvitamin D (25-OHD). BMD was determined in second metacarpals. During 5 years, 8 hip fractures in the treated group and 9 hip fracture in the untreated group occurred (p = 0.92). After 5 years, serum ucOC concentrations were higher in treated patients (9.1 +/- 1.5 ng/ml) than in untreated patients (6.0 +/- 1.2 ng/ml). ucOC was significantly related to BMD in treated but not in untreated patients. Concentrations of 25-OHD were lower in both patient groups. Percent change of BMD from baseline was lower in treated patients than in untreated patients (p < 0.01). Long-term treatment with warfarin in stroke patients seems not to be associated with an increased risk of hip fracture.


Subject(s)
Anticoagulants/administration & dosage , Atrial Fibrillation/drug therapy , Bone Density/drug effects , Cerebral Infarction/prevention & control , Hip Fractures/etiology , Accidental Falls , Administration, Oral , Aged , Aged, 80 and over , Anticoagulants/adverse effects , Atrial Fibrillation/blood , Atrial Fibrillation/complications , Biomarkers/blood , Case-Control Studies , Cerebral Infarction/blood , Cerebral Infarction/etiology , Drug Administration Schedule , Female , Hip Fractures/blood , Hip Fractures/diagnostic imaging , Hip Fractures/epidemiology , Humans , Incidence , Male , Osteocalcin/blood , Radiography , Risk Assessment , Risk Factors , Time Factors , Vitamin D/analogs & derivatives , Vitamin D/blood
19.
Neurology ; 68(12): 911-5, 2007 Mar 20.
Article in English | MEDLINE | ID: mdl-17372126

ABSTRACT

BACKGROUND: There is a high incidence of hip fractures in patients with Parkinson disease (PD). Bone mineral density (BMD) is decreased in patients with PD, correlating with the immobilization-induced bone resorption and hypovitaminosis D with compensatory hyperparathyroidism. OBJECTIVE: To evaluate the effectiveness of risedronate, an inhibitor of bone resorption, on osteoporosis and the risk of hip fractures in elderly men with PD. METHODS: This was a 2-year, randomized, double-blind, placebo-controlled trial. In a prospective study of patients with PD, 121 patients received a daily dose of 2.5 mg risedronate and vitamin D2 1,000 IU for 2 years, and the remaining 121 received placebo and vitamin D2 1,000 IU. Incidence of hip fractures was compared between the two groups. RESULTS: Nine patients sustained hip fractures in the placebo group, and three hip fractures occurred in the risedronate group. The relative risk of a hip fracture in the risedronate group vs the placebo group was 0.33 (95% CI, 0.09 to 1.20). BMD increased by 2.2% in the risedronate group and decreased by 2.9% in the placebo group (p < 0.0001). Urinary deoxypyridinoline, a bone resorption marker, decreased by 46.7% in the risedronate group and by 33.0% in the placebo group. CONCLUSION: Treatment with risedronate and vitamin D2 increases bone mineral density in elderly men with Parkinson disease and reduces the risk of hip fractures.


Subject(s)
Ergocalciferols/administration & dosage , Etidronic Acid/analogs & derivatives , Hip Fractures/prevention & control , Osteoporosis/drug therapy , Parkinson Disease/complications , Aged , Aged, 80 and over , Amino Acids/urine , Biomarkers/urine , Bone Density/drug effects , Bone Density/physiology , Bone Density Conservation Agents/administration & dosage , Bone Resorption/drug therapy , Bone Resorption/etiology , Bone Resorption/physiopathology , Double-Blind Method , Etidronic Acid/administration & dosage , Hip Fractures/etiology , Humans , Hyperparathyroidism/complications , Hyperparathyroidism/physiopathology , Male , Osteoporosis/etiology , Osteoporosis/physiopathology , Parkinson Disease/physiopathology , Placebo Effect , Prospective Studies , Risedronic Acid , Risk Assessment , Risk Factors , Treatment Outcome , Vitamin D Deficiency/complications , Vitamin D Deficiency/physiopathology
20.
Eur Neurol ; 56(3): 155-61, 2006.
Article in English | MEDLINE | ID: mdl-17035703

ABSTRACT

Little is known about bone and calcium metabolism and fracture incidence in spinocerebellar degeneration (SCD) despite frequent falls and immobilization. To address bone and calcium metabolism and fracture incidence in SCD, we conducted a 10-year prospective study in a cohort of adult patients with SCD. Bone mineral density (BMD) and serum levels of ionized calcium, parathyroid hormone, 25-hydroxyvitamin D, and pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP) were followed in 110 patients with SCD for 10 years. Age-matched healthy volunteers (n = 110) served as controls. At baseline, the SCD patients had a low BMD with high levels of serum ionized calcium and ICTP which correlated with the degree of immobilization (Barthel index). Over 10 years, serum 25-hydroxyvitamin D decreased to the osteomalacic level (<5 ng/ml), and calcium and ICTP further increased in accordance with a decreased Barthel index score. The BMD decreased by 15.2% in men and by 24.6% in women. The incidence of fractures in the patients was significantly higher as compared with the control group (men 8/49 vs. 1/42, p = 0.0428; women 16/49 vs. 2/48, p = 0.0026). Over 10 years, the BMD was significantly reduced in the SCD patients, particularly in women, which increased the risk of a fracture. Vitamin D deficiency due to sunlight deprivation, increased bone resorption due to immobilization, and frequent falls are probable causes of osteoporosis and fractures in these patients. Hypovitaminosis D and increased bone resorption may be corrected readily by the routine use of vitamin D supplements together with bisphosphonate.


Subject(s)
Bone and Bones/metabolism , Calcium/metabolism , Fractures, Bone/epidemiology , Spinocerebellar Degenerations/complications , Aged , Bone Density , Bone Development , Calcitriol/blood , Calcium/blood , Female , Humans , Longitudinal Studies , Male , Middle Aged , Multiple System Atrophy/blood , Multiple System Atrophy/complications , Parathyroid Hormone/blood , Spinocerebellar Degenerations/blood
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