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1.
J Neural Eng ; 14(6): 066004, 2017 12.
Article in English | MEDLINE | ID: mdl-28722685

ABSTRACT

OBJECTIVE: Intracortical brain-machine interfaces (BMIs) are a promising source of prosthesis control signals for individuals with severe motor disabilities. Previous BMI studies have primarily focused on predicting and controlling whole-arm movements; precise control of hand kinematics, however, has not been fully demonstrated. Here, we investigate the continuous decoding of precise finger movements in rhesus macaques. APPROACH: In order to elicit precise and repeatable finger movements, we have developed a novel behavioral task paradigm which requires the subject to acquire virtual fingertip position targets. In the physical control condition, four rhesus macaques performed this task by moving all four fingers together in order to acquire a single target. This movement was equivalent to controlling the aperture of a power grasp. During this task performance, we recorded neural spikes from intracortical electrode arrays in primary motor cortex. MAIN RESULTS: Using a standard Kalman filter, we could reconstruct continuous finger movement offline with an average correlation of ρ = 0.78 between actual and predicted position across four rhesus macaques. For two of the monkeys, this movement prediction was performed in real-time to enable direct brain control of the virtual hand. Compared to physical control, neural control performance was slightly degraded; however, the monkeys were still able to successfully perform the task with an average target acquisition rate of 83.1%. The monkeys' ability to arbitrarily specify fingertip position was also quantified using an information throughput metric. During brain control task performance, the monkeys achieved an average 1.01 bits s-1 throughput, similar to that achieved in previous studies which decoded upper-arm movements to control computer cursors using a standard Kalman filter. SIGNIFICANCE: This is, to our knowledge, the first demonstration of brain control of finger-level fine motor skills. We believe that these results represent an important step towards full and dexterous control of neural prosthetic devices.


Subject(s)
Brain-Computer Interfaces , Fingers/physiology , Motor Cortex/physiology , Motor Skills/physiology , Movement/physiology , Action Potentials/physiology , Animals , Electrodes, Implanted , Macaca mulatta , Photic Stimulation/methods
2.
BMC Cancer ; 16: 359, 2016 06 10.
Article in English | MEDLINE | ID: mdl-27282619

ABSTRACT

BACKGROUND: Osteopontin is a secreted phosphoglycoprotein that is expressed by a number of normal cells as well as a variety of tumor cells. With respect to breast cancer, osteopontin has been implicated in regulating tumor cell proliferation and migration/metastasis and may serve as a prognostic indicator. However it remains unclear whether osteopontin has the same impact in all breast cancer subtypes and in particular, osteopontin's effects in claudin-low breast cancer are poorly understood. METHODS: cDNA microarrays and qRT-PCR were used to evaluate osteopontin expression in mammary tumors from MTB-IGFIR transgenic mice and cell lines derived from these tumors. siRNA was then used to determine the impact of osteopontin knockdown on proliferation, apoptosis and migration in vitro in two murine claudin-low cell lines as well as identify the receptor mediating osteopontin's physiologic effects. RESULTS: Osteopontin was expressed at high levels in mammary tumors derived from MTB-IGFIR transgenic mice compared to normal mammary tissue. Evaluation of cell lines derived from different mammary tumors revealed that mammary tumor cells with claudin-low characteristic expressed high levels of osteopontin whereas mammary tumor cells with mixed luminal and basal-like features expressed lower levels of osteopontin. Reduction of osteopontin levels using siRNA significantly reduced proliferation and migration while increasing apoptosis in the claudin-low cell lines. Osteopontin's effect appear to be mediated through a receptor containing ITGAV and not through CD44. CONCLUSIONS: Our data suggests that mammary tumors with a mixed luminal/basal-like phenotype express high levels of osteopontin however this osteopontin appears to be largely produced by non-tumor cells in the tumor microenvironment. In contrast tumor cells with claudin-low characteristics express high levels of osteopontin and a reduction of osteopontin in these cells impaired proliferation, survival and migration.


Subject(s)
Claudins/metabolism , Gene Expression Profiling/methods , Mammary Neoplasms, Experimental/metabolism , Oligonucleotide Array Sequence Analysis/methods , Osteopontin/genetics , Osteopontin/metabolism , Animals , Apoptosis , Cell Line, Tumor , Cell Movement , Cell Proliferation , Female , Gene Knockdown Techniques , Mammary Neoplasms, Experimental/genetics , Mice , Mice, Transgenic
3.
J Aquat Anim Health ; 23(2): 62-77, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21834329

ABSTRACT

The operation of the Federal Columbia River Power System (FCRPS) has negatively affected threatened and endangered salmonid populations in the Pacific Northwest. Barging Snake River spring Chinook salmon Oncorhynchus tshawytscha through the FCRPS is one effort to mitigate the effect of the hydrosystem on juvenile salmon out-migration. However, little is known about the occurrence and transmission of infectious agents in barged juvenile salmon relative to juvenile salmon that remain in-river to navigate to the ocean. We conducted a survey of hatchery-reared spring Chinook salmon at various points along their out-migration path as they left their natal hatcheries and either migrated in-river or were barged through the FCRPS. Salmon kidneys were screened by polymerase chain reaction for nine pathogens and one family of water molds. Eight pathogens were detected; the most prevalent were Renibacterium salmoninarum and infectious hematopoietic necrosis virus. Species in the family Saprolegniaceae were also commonly detected. Pathogen prevalence was significantly greater in fish that were barged through the FCRPS than in fish left to out-migrate in-river. These results suggest that the transmission of infectious agents to susceptible juvenile salmon occurs during the barging process. Therefore, management activities that reduce pathogen exposure during barging may increase the survival of juvenile Chinook salmon after they are released.


Subject(s)
Animal Migration/physiology , Aquaculture , Fish Diseases/microbiology , Rivers , Salmon/physiology , Animals , Fish Diseases/epidemiology , Idaho/epidemiology , Kidney/microbiology , Oregon/epidemiology , Prevalence
4.
Water Res ; 41(19): 4287-98, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17628629

ABSTRACT

Many human pathogenic viruses are transmitted via the oral-fecal route and water is one possible vector, representing a risk for public health. Sixty-one large-volume water samples from storm drains in California were processed by a two-step hollow fiber ultrafiltration procedure followed by molecular analysis for human enterovirus and adenovirus types. Each sample was spiked with a surrogate, the benign bacteriophage PP7. Both surrogate and human viruses were quantified by newly designed TaqMan PCR assays. Equations were developed that account for the main variables in the procedure: recovery of the ultrafiltration, efficiency of nucleic acid extraction, and effect of inhibitors on the amplification of viral targets. Adenovirus 40/41 was detected in one sample at 230 genomes per liter, and no other adenovirus or enterovirus types were found. Samples that resulted in nondetects are reported together with the corresponding sample-specific limit of detection (S(LOD)), a useful tool when estimating the public health risk associated with the contact or ingestion of water. Virus concentrations did not correlate with traditional viable indicator concentrations or any of the physicochemical parameters measured. In contrast, coliform concentrations were correlated with total suspended solids. To our knowledge, this is the first study where all factors known to influence limits of detection have been investigated and integrated into equations that are widely applicable to the quantification of viruses or other microbial targets by PCR.


Subject(s)
Viruses/isolation & purification , Water Microbiology , Base Sequence , California , DNA Primers , Polymerase Chain Reaction , Reference Standards , Viruses/classification , Viruses/genetics
5.
J Water Health ; 4(1): 67-75, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16604839

ABSTRACT

The removal of target DNA by magnetic capture hybridization (MCH) from constituents inhibitory to amplification by polymerase chain reaction (PCR) was evaluated using Salmonella as the test pathogen. Hybrids were subjected to both conventional and quantitative real-time PCR (qPCR). When PCR inhibitors commonly found in water were added to the reaction, MCH-PCR increased the detection sensitivity on the order of 8 to 2,000-fold compared with the system using only PCR. To determine the selectivity of MCH for target DNA (Salmonella), different amounts of non-target DNA (Escherichia coli) were added to the qPCR reaction. The highest non-target DNA concentration interfered with the amplification by qPCR alone, while MCH-qPCR was unaffected. Average recovery of Salmonella DNA by MCH-qPCR was 31% using optimized buffers, washing solutions and enzymatic digestion. A recovery function was proposed in order to calculate the real cell number based on the measured value. Preliminary testing confirmed the suitability of this method for analysis of natural waters.


Subject(s)
Magnetics , Oligonucleotide Array Sequence Analysis/methods , Polymerase Chain Reaction/methods , Salmonella/isolation & purification , Water Microbiology , Water Supply/analysis , Salmonella/genetics , United States
6.
Phys Rev Lett ; 86(17): 3899-902, 2001 Apr 23.
Article in English | MEDLINE | ID: mdl-11329352

ABSTRACT

2D spectrally resolved ultrafast (<200 fs) IR vibrational echo experiments were performed on Rh(CO)(2)acac [(acetylacetonato)dicarbonylrhodium (I)]. The 2D spectra display features that reflect the 0-1 and 1-2 transitions and the combination band transition of the symmetric (S) and antisymmetric (A) CO stretching modes. Three oscillations in the data arise from the frequency difference between the S and A modes (quantum beats) and the S and A anharmonicities. A new explanation is given for these "anharmonic" oscillations. Calculations show that spectral resolution enables the 0-1 and 1-2 dephasing to be measured independently.


Subject(s)
Organometallic Compounds/chemistry , Rhodium , Spectrophotometry, Infrared/methods , Signal Processing, Computer-Assisted , Thermodynamics
7.
Osteoporos Int ; 11(7): 556-61, 2000.
Article in English | MEDLINE | ID: mdl-11069188

ABSTRACT

To examine the risk of mortality following all clinical fractures, we followed 6459 women age 55-81 years participating in the Fracture Intervention Trial for an average of 3.8 years. All fractures and deaths were confirmed by medical record or death certificate. Clinical fractures were fractures that came to medical attention. Fracture status was used as a time-dependent covariate in proportional hazards models. The 907 women who experienced a fracture were older, had lower bone mineral density and were more likely to report a positive fracture history. A total of 122 women died over the course of the study with 23 of these deaths occurring after a clinical fracture. The age-adjusted relative risk (95% confidence intervals) of dying following a clinical fracture was 2.15 (1.36, 3.42). This primarily reflected the higher mortality following a hip fracture, 6.68 (3.08, 14.52); and clinical vertebral fracture, 8.64 (4.45, 16.74). Results were similar after adjusting for treatment assignment, health status and specific common comorbidities. There was no increase in mortality following a forearm or other fracture (non-hip, non-wrist, nonvertebral fracture). In conclusion, clinical vertebral fractures and hip fractures are associated with a substantial increase in mortality among a group of relatively healthy older women.


Subject(s)
Fractures, Bone/mortality , Aged , Aged, 80 and over , Alendronate/therapeutic use , Bone Density/physiology , Female , Follow-Up Studies , Fractures, Bone/prevention & control , Hip Fractures/mortality , Humans , Middle Aged , Postmenopause , Prevalence , Risk Factors , Spinal Fractures/mortality , United States/epidemiology
8.
J Clin Endocrinol Metab ; 85(11): 4118-24, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11095442

ABSTRACT

We examined the effect of alendronate treatment for 3-4 yr on risk of new fracture among 3658 women with osteoporosis enrolled in the Fracture Intervention Trial. This cohort included women with existing vertebral fracture and those with osteoporosis as defined by T score of less than -2.5 at the femoral neck but without vertebral fracture. All analyses were prespecified in the data analysis plan. The magnitudes of reduction of fracture incidence with alendronate were similar in both groups. The two groups were, therefore, pooled to obtain a more precise estimate of the effect of alendronate on relative risk of fracture (relative risk, 95% confidence interval): hip (0.47, 0.26-0.79), radiographic vertebral (0.52, 0.42-0.66), clinical vertebral (0.55, 0.36-0.82), and all clinical fractures (0.70, 0.59-0.82). Reductions in risk of clinical fracture were statistically significant by 12 months into the trial. We conclude that reductions in fracture risk during treatment with alendronate are consistent in women with existing vertebral fractures and those without such fractures but with bone mineral density in the osteoporotic range. Furthermore, reduction in risk is evident early in the course of treatment. This pooled analysis provides a more precise estimate of the antifracture efficacy of alendronate in women with osteoporosis than that in prior reports.


Subject(s)
Alendronate/therapeutic use , Fractures, Bone/prevention & control , Osteoporosis, Postmenopausal/drug therapy , Spinal Fractures/epidemiology , Aged , Cohort Studies , Female , Follow-Up Studies , Fractures, Bone/diagnostic imaging , Fractures, Bone/epidemiology , Humans , Incidence , Radiography , Risk Factors , Spinal Fractures/diagnostic imaging , Spinal Fractures/prevention & control , Time Factors , Treatment Outcome
9.
Mayo Clin Proc ; 75(9): 888-96, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10994823

ABSTRACT

OBJECTIVE: To evaluate the ability of self-reported risk factors to identify postmenopausal women likely to have extant vertebral fractures because approximately two thirds of women with radiographic evidence of vertebral fracture are unaware of the fracture. PATIENTS AND METHODS: Questionnaire and spinal radiographic data were collected from postmenopausal women with a femoral neck bone mineral density T score of -1.6 or lower during screening for the Fracture Intervention Trial. Logistic regression was used to identify risk factors for extant vertebral fractures and to derive a final multivariable model. RESULTS: Almost two thirds of 25,816 women 55 years and older met the bone density criterion, and 21% of those had an extant vertebral fracture. The final model consisted of 5 self-reported items: history of vertebral fracture, history of nonvertebral fracture, age, height loss, and diagnosis of osteoporosis. These were combined to yield a Prevalent Vertebral Fracture Index (PVFI). The prevalence of women with vertebral fracture varied from 3.8% to 62.3% over the range PVFI of 0 to greater than 5. Among the 13,051 women screened with spinal radiographs, a PVFI of 4 or greater identified 65.5% of women with vertebral fractures (sensitivity), with a specificity of 68.6%. Excluding 881 women who reported prior vertebral fractures reduced the sensitivity to 53.6 % and increased the specificity to 70.7% but did not alter the fracture prevalence at PVFI values less than 6. CONCLUSION: In this population, 5 simple questions identified women who were likely to have undiagnosed vertebral fractures. Further research is needed to determine the validity of this index in other populations, including women without low bone mineral density.


Subject(s)
Mass Screening/methods , Medical History Taking/methods , Osteoporosis, Postmenopausal/complications , Spinal Fractures/diagnosis , Spinal Fractures/etiology , Surveys and Questionnaires/standards , Age Distribution , Aged , Aged, 80 and over , Body Height , Bone Density , Female , Femur Neck/diagnostic imaging , Humans , Logistic Models , Middle Aged , Multivariate Analysis , Prevalence , Radiography , Reproducibility of Results , Risk Factors , Sensitivity and Specificity , Spinal Fractures/epidemiology , United States/epidemiology
10.
Aging (Milano) ; 12(1): 1-12, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10746426

ABSTRACT

Dosing convenience is a key element in the effective management of any chronic disease, and is particularly important in the long-term management of osteoporosis. Less frequent dosing with any medication may enhance compliance, thereby maximizing the effectiveness of therapy. Animal data support the rationale that once-weekly dosing with alendronate 70 mg (7 times the daily oral treatment dose) could provide similar efficacy to daily dosing with alendronate 10 mg due to its long duration of effect in bone. In addition, dog studies suggest that the potential for esophageal irritation, observed with daily oral bisphosphonates, may be substantially reduced with once-weekly dosing. This dosing regimen would provide patients with increased convenience and would be likely to enhance patient compliance. We compared the efficacy and safety of treatment with oral once-weekly alendronate 70 mg (N=519), twice-weekly alendronate 35 mg (N=369), and daily alendronate 10 mg (N=370) in a one-year, double-blind, multicenter study of postmenopausal women (ages 42 to 95) with osteoporosis (bone mineral density [BMD] of either lumbar spine or femoral neck at least 2.5 SDs below peak premenopausal mean, or prior vertebral or hip fracture). The primary efficacy endpoint was the comparability of increases in lumbar spine BMD, using strict pre-defined equivalence criteria. Secondary endpoints included changes in BMD at the hip and total body and rate of bone turnover, as assessed by biochemical markers. Both of the new regimens fully satisfied the equivalence criteria relative to daily therapy. Mean increases in lumbar spine BMD at 12 months were: 5.1% (95% CI 4.8, 5.4) in the 70 mg once-weekly group, 5.2% (4.9, 5.6) in the 35 mg twice-weekly group, and 5.4% (5.0, 5.8) in the 10 mg daily treatment group. Increases in BMD at the total hip, femoral neck, trochanter, and total body were similar for the three dosing regimens. All three treatment groups similarly reduced biochemical markers of bone resorption (urinary N-telopeptides of type I collagen) and bone formation (serum bone-specific alkaline phosphatase) into the middle of the premenopausal reference range. All treatment regimens were well tolerated with a similar incidence of upper GI adverse experiences. There were fewer serious upper GI adverse experiences and a trend toward a lower incidence of esophageal events in the once-weekly dosing group compared to the daily dosing group. These data are consistent with preclinical animal models, and suggest that once-weekly dosing has the potential for improved upper GI tolerability. Clinical fractures, captured as adverse experiences, were similar among the groups. We conclude that the alendronate 70 mg once-weekly dosing regimen will provide patients with a more convenient, therapeutically equivalent alternative to daily dosing, and may enhance compliance and long-term persistence with therapy.


Subject(s)
Alendronate/administration & dosage , Alendronate/pharmacokinetics , Osteoporosis, Postmenopausal/drug therapy , Administration, Oral , Adult , Aged , Aged, 80 and over , Alendronate/adverse effects , Alendronate/therapeutic use , Bone Density/drug effects , Dose-Response Relationship, Drug , Double-Blind Method , Drug Administration Schedule , Female , Femur Neck/metabolism , Gastrointestinal Diseases/chemically induced , Humans , Lumbosacral Region , Middle Aged , Osteoporosis, Postmenopausal/metabolism , Spine/metabolism , Therapeutic Equivalency
11.
J Am Geriatr Soc ; 48(3): 241-9, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10733048

ABSTRACT

OBJECTIVES: To determine the relationship between prevalent vertebral deformities and the risk of mortality and hospitalization in older women with low bone mass. DESIGN: A prospective cohort study. SETTING: Eleven clinical centers in the United States. PARTICIPANTS: A total of 6459 community-dwelling women with low bone mass aged 55 to 81 participated in the Fracture Intervention Trial (FIT), a multicenter clinical trial of alendronate that enrolled women into one of two study arms based solely on the presence or absence of existing radiographic vertebral deformities. There were 2027 women with at least one vertebral deformity enrolled in the vertebral fracture arm of FIT and followed prospectively for an average of 2.9 years, whereas 4432 women with no vertebral deformity were enrolled in the clinical fracture arm of FIT and followed prospectively for an average of 4.2 years. MEASUREMENTS: Determination of prevalent vertebral deformities on baseline lateral thoracic and lumbar spine radiographs was made at the coordinating center using a combination of radiographic morphometry by digitization and semiquantitative radiologic interpretation. Deaths were confirmed by obtaining copies of original death certificates of all participants who died. Episodes of hospitalization were captured through adverse event reporting; hospitalizations resulting solely from adverse events containing the words "fracture" or "trauma" were excluded from the analyses. RESULTS: During the follow-up period, 122 women died, and 1676 women were hospitalized on at least one occasion for reasons not related solely to fracture. Compared with women without prevalent vertebral deformities, those women with prevalent deformities had higher risks of mortality (age- and treatment assignment-adjusted relative risk 1.60, 95% confidence interval (CI), 1.10-2.32) and hospitalization (age- and treatment assignment-adjusted relative risk 1.18, 95% CI, 1.06-1.31). In addition, further adjustment for other factors, including smoking status, physical activity, hypertension, coronary heart disease, obstructive lung disease, any fracture since the age of 50, health status, total hip BMD, and body mass index did not alter the association between prevalent vertebral deformities and risk of mortality substantially (multivariate relative risk 1.49, 95% CI, 1.05-2.21). Adjustment for all these factors and diabetes also did not change the relationship between prevalent vertebral deformities and hospitalization (multivariate relative risk 1.14, 95% CI, 1.02-1.27). Rates of mortality and hospitalization increased with increasing number of prevalent vertebral deformities (tests for trend P < .01). CONCLUSIONS: Prevalent vertebral deformities in older women with low bone mass are associated with increased risks of mortality and hospitalization. Only a portion of this increased risk was explained by other known predictors of these outcomes.


Subject(s)
Hospitalization/statistics & numerical data , Osteoporosis, Postmenopausal/mortality , Spine/pathology , Absorptiometry, Photon , Aged , Aged, 80 and over , Aging/physiology , Bone Density , Female , Humans , Middle Aged , Osteoporosis, Postmenopausal/pathology , Poisson Distribution , Prevalence , Prospective Studies , Risk Factors , Spine/diagnostic imaging , United States/epidemiology
12.
J Appl Psychol ; 85(1): 86-101, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10740959

ABSTRACT

This study compares the careers of matched samples of 69 female executives and 69 male executives by examining perceived barriers and facilitators of advancement, self-reported developmental experiences, and career histories. Consistent with tokenism theory, women reported greater barriers, such as lack of culture fit and being excluded from informal networks, and greater importance of having a good track record and developing relationships to facilitate advancement than did men. Career success, measured by organizational level and compensation, was positively related to breadth of experience and developmental assignments for both genders, but successful women were less likely than successful men to report that mentoring facilitated their advancement. Developmental experiences and career histories were similar for female and male executives, but men had more overseas assignments and women had more assignments with nonauthority relationships.


Subject(s)
Administrative Personnel , Career Mobility , Prejudice , Adult , Female , Humans , Interpersonal Relations , Male , Middle Aged , Sex Factors
13.
Arch Intern Med ; 160(1): 77-85, 2000 Jan 10.
Article in English | MEDLINE | ID: mdl-10632308

ABSTRACT

BACKGROUND: Women with new vertebral fractures have an increased risk of back pain and functional limitation because of back pain. Alendronate sodium treatment reduces the risk of new vertebral fracture by 50% in postmenopausal women with osteoporosis. OBJECTIVE: To determine the effect of alendronate therapy on days affected by back pain in postmenopausal women with existing vertebral fractures. DESIGN: Three-year, placebo-controlled, randomized, double-blind study. SETTING: Fifteen university-based research clinics in the United States. PARTICIPANTS: A total of 2027 postmenopausal women aged 55 to 81 years with low femoral neck bone density and a preexisting vertebral fracture. INTERVENTION: Alendronate sodium (5 mg/d for 2 years and 10 mg/d for the third year) or placebo. MAIN OUTCOME MEASURES: Occurrence and severity of back pain, number of days with back pain, and number of days of bed rest or limited activity because of back pain during 3 years of follow-up. RESULTS: Irrespective of treatment assignment, women with new, clinically recognized vertebral fractures during follow-up had an increased risk of days of bed disability and days of limited activity because of back pain after the fracture. Women receiving alendronate reported an average of 3.2 fewer days of bed rest (P = .001) and 11.4 fewer days of limited activity (not including days of bed rest) because of back pain (P = .04) during follow-up than those receiving placebo. In the alendronate group, relative to the placebo group, there was a reduced risk of 1 or more bed-rest days (relative risk, 0.68; 95% confidence interval, 0.53-0.87), of 7 or more bed-rest days (0.44; 0.30-0.64), and of 7 or more limited-activity days (0.87; 0.76-0.99). There were no statistically significant differences between treatment groups in the frequency of days of back pain or increases in back-related disability between baseline and study end. CONCLUSION: In postmenopausal women with preexisting vertebral fracture, alendronate therapy for 3 years reduced the number of days of bed disability and days of limited activity caused by back pain.


Subject(s)
Alendronate/therapeutic use , Back Pain/drug therapy , Bed Rest , Osteoporosis, Postmenopausal/complications , Spinal Fractures/complications , Spinal Fractures/etiology , Activities of Daily Living , Aged , Back Pain/etiology , Bone Density/drug effects , Double-Blind Method , Female , Humans , Incidence , Middle Aged , Risk , Severity of Illness Index , Treatment Outcome
14.
Osteoporos Int ; 9(5): 455-60, 1999.
Article in English | MEDLINE | ID: mdl-10550466

ABSTRACT

Alendronate has been shown to increase bone density among early postmenopausal women. Osteoporosis is common among both Asian and Caucasian women, but most clinical trials have consisted primarily of Caucasian women, and it does not appear that the effectiveness of antiresorptive agents such as alendronate has been compared between the two races. In this study we compared the response of bone density and biochemical markers to alendronate among 136 Asian and 126 Caucasian women who participated in the Early Postmenopausal Interventional Cohort (EPIC) at the Hawaii center. Approximately 40 women of each race were randomly assigned to placebo or to 2.5 mg/day or 5 mg/day alendronate. Bone mineral density (BMD) was measured at the spine, total hip and total body at baseline, 12 months and 24 months; biochemical markers of bone turnover were measured at 6-month intervals. Responses were greater for the 5 mg dose than 2.5 mg, and were similar in the two races. For example, mean (SE) changes in spine BMD at 24 months for Caucasians and Asians, respectively, were -1.9% (0.5%) and -1.9% (0.4%) for the placebo group, 2.0% (0.5%) and 3.4% (0.5%) at 2.5 mg/day and 4.2% (0. 5%) for both races at 5 mg/day. Corresponding changes in urinary N-telopeptide collagen crosslinks were -33.6% (5.6%) and -27.8% (5. 8%) for placebo, -51.4% (4.0%) and -62.1 (4.3%) at 2.5 mg/day and -70.8% (2.4%) and -73.5% (3.1%) at 5 mg/day. We conclude that (1) the rate of bone loss in untreated Asian and Caucasian postmenopausal women is similar, with the possible exception of the hip; (2) 5 mg alendronate daily provides greater skeletal benefits than 2.5 mg/day in both Asian and Caucasian early postmenopausal women; and (3) the response at 5 mg/day is similar in the two races.


Subject(s)
Alendronate/administration & dosage , Bone Density/drug effects , Bone Resorption/drug therapy , Osteoporosis, Postmenopausal/drug therapy , Alendronate/therapeutic use , Alkaline Phosphatase/blood , Asia/ethnology , Biomarkers/blood , Biomarkers/urine , Collagen/urine , Collagen Type I , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Humans , Lumbar Vertebrae/physiopathology , Middle Aged , Osteocalcin/blood , Osteoporosis, Postmenopausal/metabolism , Osteoporosis, Postmenopausal/physiopathology , Peptides/urine , Regression Analysis , United States
15.
Bone ; 25(5): 613-9, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10574584

ABSTRACT

Vertebral fractures are the most common osteoporotic fracture and are associated with significant pain and disability. Prior vertebral fracture and low bone mineral density (BMD) are strong predictors of new vertebral fracture. Using data from 6082 women, ages 55-80 years, in the Fracture Intervention Trial (a randomized, placebo-controlled trial of the antiresorptive agent, alendronate), we explored the association of the number of prior vertebral fractures with the risk of new fractures and whether this association is influenced by the spinal location of fractures. The risk of future vertebral fractures increased with the number of prevalent fractures, independently of age and BMD; in the placebo group, more than half of the women with five or more fractures at baseline developed new vertebral fractures, compared to only 3.8% of women without prior vertebral fractures. The magnitude of association with an increased risk of future vertebral fractures was equal for prevalent fractures located in either the "lower" (T12-L4) (relative risk [RR] = 2.9; 95% CI = 1.9, 3.6) or "upper" (T4-10) spine (RR = 2.6; 95% CI = 1.9, 3.6). We found no evidence that the effectiveness of alendronate in reducing the risk of future vertebral fracture was attenuated in women with up to five or more prevalent fractures, or that it varied by the location of prevalent fractures. However, prevalent vertebral fractures in any location were more strongly associated with risk of new fractures in the upper (RR = 5.2; 95% CI = 3.2, 8.3) than in the lower spine (2.3; 1.6, 3.3). In addition, each 1 SD decrease in spinal BMD was associated with a 2.1 (1.7, 2.6) times greater odds of new fracture in the upper spine, compared with 1.5 (1.3, 1.8) for the lower spine. These findings suggest that, in older women, osteoporosis may be a stronger risk factor for new fractures in the upper (vs. lower) thoracolumbar spine, although we found no evidence that the location of prior fractures should influence treatment decisions. Physicians should recognize that prior vertebral fractures are a strong risk factor for future fractures, and consider treating such patients to reduce their risk of subsequent fractures.


Subject(s)
Alendronate/therapeutic use , Bone Density/physiology , Lumbar Vertebrae/injuries , Spinal Fractures/complications , Spinal Fractures/prevention & control , Thoracic Vertebrae/injuries , Aged , Aged, 80 and over , Bone Density/drug effects , Bone Resorption/drug therapy , Bone Resorption/epidemiology , Female , Humans , Incidence , Lumbar Vertebrae/drug effects , Middle Aged , Osteoporosis, Postmenopausal/complications , Osteoporosis, Postmenopausal/drug therapy , Osteoporosis, Postmenopausal/epidemiology , Predictive Value of Tests , Prevalence , Prognosis , Risk Factors , Spinal Fractures/epidemiology , Thoracic Vertebrae/drug effects
16.
Cognition ; 72(1): 45-66, 1999 Aug 25.
Article in English | MEDLINE | ID: mdl-10520564

ABSTRACT

Children interpreted an utterance made by a protagonist with a false belief, such as, 'I would like the car in the garage.' Calculating the speaker's belief in conjunction with the literal meaning of the utterance would lead to the correct interpretation that the intended referent is the car on the track, given that the car in the garage swapped places with the one on the track. In Experiments 1 and 2, many children aged around 4 and 5 years wrongly indicated the car in the garage. In contrast, many correctly indicated the car on the track when it was unnecessary to consider the speaker's belief because the utterance was, 'the car I put in the garage'. Six-year-olds found both kinds of utterance equally easy in Experiment 1, while 3-year-olds had equal difficulty with both. In Experiments 2 and 3, the speaker gave an ambiguous utterance and many children aged between 3 and 6 years successfully used information about the speaker's belief to identify which of several candidate referents was intended. We discuss the results in relation to characteristics of utterance comprehension and consider implications for developments in understanding the mind by children beyond 4 years.


Subject(s)
Cognition , Language Development , Age Factors , Child , Child, Preschool , Culture , Female , Humans , Male , Psycholinguistics , Psychology, Child
17.
Aust Vet J ; 77(2): 85-92, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10078353

ABSTRACT

OBJECTIVE: To better characterise the bone and joint problems which can develop in Scottish Fold cats. DESIGN: Retrospective study of cases seen in five veterinary clinics and radiographic survey of cats in a cattery. RESULTS: Six Scottish Fold cats (four castrated males, two spayed females) aged between 5 months and 6 years were presented for signs of skeletal disease including lameness, reluctance to jump, a stiff stilted gait, short misshapen distal limbs, swelling of plantar tarsometatarsal regions and short thick inflexible tails. A further four cases (one male, three females, 15 months to 11 years) were identified by radiographic screening of a cattery. A diagnosis of osteochondrodysplasia was based on characteristic radiological findings including irregularity in the size and shape of tarsal, carpal, metatarsal and metacarpal bones, phalanges and caudal vertebrae, narrowed joint spaces, and progressive new bone formation around joints of distal limbs with diffuse osteopenia of adjacent bone. A plantar exostosis caudal to the calcaneus was present in advanced cases. In all nine cases where pedigree information was available, affected cats allegedly originated from the mating of a Scottish Fold to a cat with normal ears. The severity and time of onset of physical signs, and rate of progression and extent of radiographic abnormalities, varied from case to case. Limited histological observations suggested the underlying problem may be an osteochondrodysplasia, related to inadequate cartilage maturation. Clinical signs were ameliorated by administration of pentosan subcutaneously in two of three cats in which it was trailed, and one of these also benefited from an oral glycosaminoglycan preparation. CONCLUSIONS: Clinical and radiological findings were ascribed to defective maturation and function of cartilage, particularly in the distal limbs, ears and tail. As all Scottish Fold cats suffered from osteochondrodysplasia of some degree, the best solution would be to avoid using fold-eared cats for breeding and instead use Scottish shorthairs.


Subject(s)
Cartilage, Articular/pathology , Cat Diseases/genetics , Lameness, Animal/etiology , Osteochondrodysplasias/veterinary , Animals , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Cat Diseases/diagnostic imaging , Cat Diseases/physiopathology , Cats , Fatal Outcome , Female , Forelimb/diagnostic imaging , Forelimb/physiopathology , Glycosaminoglycans/therapeutic use , Hindlimb/diagnostic imaging , Hindlimb/physiopathology , Lameness, Animal/diagnostic imaging , Lameness, Animal/physiopathology , Male , Osteochondrodysplasias/diagnostic imaging , Osteochondrodysplasias/genetics , Pedigree , Pentosan Sulfuric Polyester/therapeutic use , Radiography , Retrospective Studies , Tail/diagnostic imaging , Tail/physiopathology , Treatment Outcome
18.
Int J Clin Pract Suppl ; 101: 46-50, 1999 Apr.
Article in English | MEDLINE | ID: mdl-12669740

ABSTRACT

Results from the now-complete Vertebral Fracture Study have been reported elsewhere. The purpose of this report is to review these results in the context of the overall design and implementation of the Fracture Intervention Trial (FIT), and to comment on their implications for clinical practice. The FIT results have important implications for the treatment of osteoporosis in clinical practice. The 51% decrease in the incidence of hip fracture represents the first documentation of any medication's ability to prevent fractures of the hip in community-dwelling women. The 48% reduction in the incidence of morphometrically documented vertebral fracture is also important, as these types of fracture are associated with significant pain and disability and are predictive of future vertebral and hip fractures.


Subject(s)
Alendronate/therapeutic use , Osteoporosis, Postmenopausal/drug therapy , Spinal Fractures/prevention & control , Aged , Aged, 80 and over , Female , Fractures, Bone/etiology , Fractures, Bone/prevention & control , Humans , Middle Aged , Osteoporosis, Postmenopausal/complications , Reproducibility of Results , Risk Factors , Spinal Fractures/etiology
19.
Clin Ther ; 20(5): 933-44, 1998.
Article in English | MEDLINE | ID: mdl-9829445

ABSTRACT

Calcium's ability to prevent bone loss in early postmenopausal women is controversial. We used data on 394 women from the placebo group of the Early Postmenopausal Interventional Cohort study, a clinical trial of alendronate, to investigate the relation of calcium intake to bone loss. Calcium intake was recorded, and bone mineral density (BMD) (in the lumbar spine, total body, forearm, and hip) and biochemical markers of bone turnover (serum total alkaline phosphatase, serum osteocalcin, and urinary N-telopeptide crosslink levels) were measured at baseline and annually thereafter. Women whose baseline calcium intake was <500 mg/d were advised to increase their calcium intake. Mean (+/- SE) BMD decreased by 1.9% +/- 0.16% at the lumbar spine and 1.6% +/- 0.14% at the hip over the 24-month period. Despite wide variations in baseline calcium intake and changes in calcium intake, these measures were not significantly associated with changes in BMD or bone turnover. Even women whose total calcium intake was >1333 mg/d (the highest tertile of total calcium intake) showed a decline in BMD of almost 2%, similar to declines in the lower two tertiles of total calcium intake (<869 and 869-1333 mg/d, respectively). Increased calcium intake resulted in modest mean increases of approximately 200 mg/d. We were unable to demonstrate that increases of this magnitude or much greater (1 g/d) were protective against declines in BMD at any site, even in women who had the lowest calcium intake at baseline. In addition to adequate calcium intake, more effective therapy appears to be required when the therapeutic goal is to increase or maintain BMD.


Subject(s)
Calcium, Dietary/administration & dosage , Osteoporosis, Postmenopausal/prevention & control , Bone Density , Female , Humans , Middle Aged
20.
JAMA ; 280(24): 2077-82, 1998.
Article in English | MEDLINE | ID: mdl-9875874

ABSTRACT

CONTEXT: Alendronate sodium reduces fracture risk in postmenopausal women who have vertebral fractures, but its effects on fracture risk have not been studied for women without vertebral fractures. OBJECTIVE: To test the hypothesis that 4 years of alendronate would decrease the risk of clinical and vertebral fractures in women who have low bone mineral density (BMD) but no vertebral fractures. DESIGN: Randomized, blinded, placebo-controlled trial. SETTING: Eleven community-based clinical research centers. SUBJECTS: Women aged 54 to 81 years with a femoral neck BMD of 0.68 g/cm2 or less (Hologic Inc, Waltham, Mass) but no vertebral fracture; 4432 were randomized to alendronate or placebo and 4272 (96%) completed outcome measurements at the final visit (an average of 4.2 years later). INTERVENTION: All participants reporting calcium intakes of 1000 mg/d or less received a supplement containing 500 mg of calcium and 250 IU of cholecalciferol. Subjects were randomly assigned to either placebo or 5 mg/d of alendronate sodium for 2 years followed by 10 mg/d for the remainder of the trial. MAIN OUTCOME MEASURES: Clinical fractures confirmed by x-ray reports, new vertebral deformities detected by morphometric measurements on radiographs, and BMD measured by dual x-ray absorptiometry. RESULTS: Alendronate increased BMD at all sites studied (P<.001) and reduced clinical fractures from 312 in the placebo group to 272 in the intervention group, but not significantly so (14% reduction; relative hazard [RH], 0.86; 95% confidence interval [CI], 0.73-1.01). Alendronate reduced clinical fractures by 36% in women with baseline osteoporosis at the femoral neck (>2.5 SDs below the normal young adult mean; RH, 0.64; 95% CI, 0.50-0.82; treatment-control difference, 6.5%; number needed to treat [NNT], 15), but there was no significant reduction among those with higher BMD (RH, 1.08; 95% CI, 0.87-1.35). Alendronate decreased the risk of radiographic vertebral fractures by 44% overall (relative risk, 0.56; 95% CI, 0.39-0.80; treatment-control difference, 1.7%; NNT, 60). Alendronate did not increase the risk of gastrointestinal or other adverse effects. CONCLUSIONS: In women with low BMD but without vertebral fractures, 4 years of alendronate safely increased BMD and decreased the risk of first vertebral deformity. Alendronate significantly reduced the risk of clinical fractures among women with osteoporosis but not among women with higher BMD.


Subject(s)
Alendronate/therapeutic use , Bone Density , Fractures, Bone/prevention & control , Osteoporosis, Postmenopausal/drug therapy , Absorptiometry, Photon , Aged , Aged, 80 and over , Calcium/administration & dosage , Cholecalciferol/administration & dosage , Dietary Supplements , Female , Femur Neck/diagnostic imaging , Femur Neck/pathology , Humans , Middle Aged , Risk , Spinal Fractures/prevention & control , Spine/diagnostic imaging , Spine/pathology
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