Structure of LRRK2 in Parkinson's disease and model for microtubule interaction.

Leucine-rich repeat kinase 2 (LRRK2) is the most commonly mutated gene in familial Parkinson's disease1 and is also linked to its idiopathic form2. LRRK2 has been proposed to function in membrane trafficking3 and colocalizes with microtubules4. Despite the fundamental importance of LRRK2 for understanding and treating Parkinson's disease, structural information on the enzyme is limited. Here we report the structure of the catalytic half of LRRK2, and an atomic model of microtubule-associated LRRK2 built using a reported cryo-electron tomography in situ structure5. We propose that the conformation of the LRRK2 kinase domain regulates its interactions with microtubules, with a closed conformation favouring oligomerization on microtubules. We show that the catalytic half of LRRK2 is sufficient for filament formation and blocks the motility of the microtubule-based motors kinesin 1 and cytoplasmic dynein 1 in vitro. Kinase inhibitors that stabilize an open conformation relieve this interference and reduce the formation of LRRK2 filaments in cells, whereas inhibitors that stabilize a closed conformation do not. Our findings suggest that LRRK2 can act as a roadblock for microtubule-based motors and have implications for the design of therapeutic LRRK2 kinase inhibitors.

Favorable clinical response and drug retention of anti-IL-6 receptor inhibitor in rheumatoid arthritis with high CRP levels: the ANSWER cohort study.

OBJECTIVE: Currently, biological disease-modifying anti-rheumatic drugs (bDMARDs) with different modes of action [tumour necrosis factor inhibitor (TNFi), interleukin-6 receptor inhibitor (IL-6Ri), or cytotoxic T-lymphocyte antigen 4-immunoglobulin (CTLA4-Ig)] are used in clinical practice to treat rheumatoid arthritis (RA). However, it is unclear which type of bDMARD is the most efficacious for a specific clinical situation. C-reactive protein (CRP) is an acute-phase reactant driven by IL-6 signalling. Here, we aimed to establish whether therapeutic efficacy differs between IL-6Ri and other bDMARDs with alternative modes of action in RA patients according to their CRP level. METHOD: RA patients treated with bDMARDs were enrolled from an observational multicentre registry in Japan. Patients were classified into three groups according to baseline CRP tertiles. The overall 3 year retention rates of each bDMARD category were assessed. The Clinical Disease Activity Index (CDAI) was also assessed before and 3, 6, and 12 months after bDMARD initiation. RESULTS: A total of 1438 RA patients were included and classified into three groups according to tertiles of baseline CRP levels (CRP1, 0-0.3; CRP2, 0.3-1.8; CRP3, 1.8-18.4 mg/dL). In CRP3, the overall 3 year drug retention rates were significantly higher for IL-6Ri than for TNFi and CTLA4-Ig (77.5 vs 48.2 vs 67.3, respectively). No significant difference was evident in terms of CDAI 12 months after bDMARD initiation in CRP1-CRP3. CONCLUSION: IL-6Ri may be a favourable therapeutic option over TNFi and CTLA4-Ig in RA patients with high CRP levels.

The relationship between sucrose intake in coffee or tea, and root or coronal caries in an elderly Japanese population.

OBJECTIVES: Few studies have examined the effect of sucrose intake in coffee or tea (SCT) on dental caries, especially root caries, in elderly people. The purpose of the present study was to examine the associations between SCT and the prevalence of root or coronal caries in community-dwelling elderly Japanese. METHODS: Participants were 370 elders aged 75 years from a larger cohort study of elders in Niigata City, Japan. Dietary habits during the preceding month were assessed with a validated brief self-administered diet history questionnaire (BDHQ). The caries examination was conducted using mirror and ball-pointed periodontal probes under artificial light. Poisson regression analysis was performed to analyze the prevalence-rate ratios (PRRs) between SCT and the root or coronal caries. The number of root or coronal caries was selected as the dependent variable for the analysis. Then, SCT (tertiles labeled low, medium and high) and other 4 variables were selected as independent variables. RESULTS: The PRRs between the number of root caries lesions and SCT were signifi cantly higher in the second (medium intake, 1.38, p ⟨ 0.001) and third tertiles (high intake, 2.07, p ⟨ 0.001). Similar tendencies were seen for the number of coronal caries lesions (PRRs in the second and third tertiles 1.74 and 2.46, respectively, both p ⟨ 0.001). CONCLUSION: A significant positive relationship was observed between sucrose in coffee and tea and the number of coronal or root caries lesions in community-dwelling elderly Japanese.

Deep-learning-based, computer-aided classifier developed with a small dataset of clinical images surpasses board-certified dermatologists in skin tumour diagnosis.

BACKGROUND: Application of deep-learning technology to skin cancer classification can potentially improve the sensitivity and specificity of skin cancer screening, but the number of training images required for such a system is thought to be extremely large. OBJECTIVES: To determine whether deep-learning technology could be used to develop an efficient skin cancer classification system with a relatively small dataset of clinical images. METHODS: A deep convolutional neural network (DCNN) was trained using a dataset of 4867 clinical images obtained from 1842 patients diagnosed with skin tumours at the University of Tsukuba Hospital from 2003 to 2016. The images consisted of 14 diagnoses, including both malignant and benign conditions. Its performance was tested against 13 board-certified dermatologists and nine dermatology trainees. RESULTS: The overall classification accuracy of the trained DCNN was 76·5%. The DCNN achieved 96·3% sensitivity (correctly classified malignant as malignant) and 89·5% specificity (correctly classified benign as benign). Although the accuracy of malignant or benign classification by the board-certified dermatologists was statistically higher than that of the dermatology trainees (85·3% ± 3·7% and 74·4% ± 6·8%, P < 0·01), the DCNN achieved even greater accuracy, as high as 92·4% ± 2·1% (P < 0·001). CONCLUSIONS: We have developed an efficient skin tumour classifier using a DCNN trained on a relatively small dataset. The DCNN classified images of skin tumours more accurately than board-certified dermatologists. Collectively, the current system may have capabilities for screening purposes in general medical practice, particularly because it requires only a single clinical image for classification.

Bendamustine-120 plus rituximab therapy for relapsed or refractory follicular lymphoma: a multicenter phase II study.

The optimal dose, schedule, and other aspects of bendamustine plus rituximab treatment remain unclear for patients with relapsed or refractory follicular lymphoma (FL). Herein, we analyzed the efficacy of bendamustine combined with rituximab (RB-120) treatment for Japanese patients with relapsed or refractory FL. This phase II clinical trial included patients with relapsed or refractory FL who received 375 mg/m2 rituximab on day 1 and 120 mg/m2 bendamustine on days 2 and 3 every 28 days for up to 6 cycles. The primary endpoint was the overall response rate (ORR), and the secondary endpoints included the complete response (CR) rate, progression-free survival (PFS), overall survival (OS), and safety. Thirty-seven patients were enrolled in the trial (median age 62 years, range 42-75 years). All patients were previously treated with rituximab-containing chemotherapy, and 83.8% were previously treated with the R-CHOP regimen. A median of 5 cycles (range 1-6) and 48.6% of patients completed 6 cycles. The ORR was 91.9% (95% confidence interval [CI] 78.1-98.3%), with a CR rate of 86.5% (95% CI 71.2-95.5%). The 3-year PFS and OS were 70.9% (95% CI 52.3-83.3%) and 88.9% (95% CI 73.1-95.7%), respectively, with the median 39.5 months follow-up duration. The most-frequently observed grade 3/4 adverse events were hematologic: lymphopenia (95%) and neutropenia (70%). No treatment-related deaths were observed. RB-120 showed a good efficacy with equivalent toxicities, compared with the bendamustine 120 mg/m2 monotherapy. However, the problem of high drop-out incidences cannot be ignored.

Hybrid transgastric approach for the treatment of gastroesophageal junction pathologies.

Flexible endoscopy has evolved to the point that it includes many endoluminal procedures that once required open or laparoscopic surgery, for instance, antireflux surgery, pyloromyotomy, mucosal and submucosal tumor resections, and even full-thickness resection. However, these procedures remain technically demanding due to flexible technology issues: difficult imaging, limited energy devices, lack of staplers, unsatisfactory suturing abilities, and so on. Transgastric laparoscopy or hybrid laparoscopy/flex endoscopy has been described for almost two decades as an alternative to a pure endoluminal approach, mainly for pancreatic pseudocyst drainage and full-thickness and mucosal resection of various lesions. The approach has never been widely adopted mostly due to cumbersome and difficult to maintain methods of gastric access. We propose to expand the indications of transgastric laparoscopy by using novel endoscopically placed ports to replicate endoscopic procedures particularly in the difficult to access proximal stomach such as endoluminal antireflux surgery. Under general anesthesia, five female pigs (mean weight: 27.6 kg) had endoscopic placement of 3, 5 mm intragastric ports (Endo-TAGSS, Leakwood KS, USA) using a technique similar to percutaneous endoscopic gastrostomy. A 5-mm laparoscope was used for visualization. Laparoendoscopic-assisted plication of the gastroesophageal junction (GEJ) was performed using 3-0 interrupted sutures (Polysorb®, Covidien, Mansfield, MA, USA). A functional lumen imagine probe (EndoFLIP®, Crospon, Inc., Galway, Ireland) was used to measure diameter, cross sectional area (CSA), distensibility, and compliance of GEJ before and after intervention. Once the TAGSS ports were removed, the gastrotomies were closed by using endoscopic over-the-scope clips. At the end of the procedure, animals were euthanized. Five laparoendoscopic-assisted endoluminal plications were performed. The mean operative time was 65.6 min (Endoscopic evaluation: 3.2 min, TAGSS Insertion: 11 min, EndoFLIP evaluation + GEJ Plication: 43.25 min, gastric wall closure: 15 minutes). In all cases, this technique was effective and allowed to achieve an adequate GEJ plication by endoscopic grading and EndoFLIP measurements. Median pre-plication GEJ diameter (D) and median pre-plication GEJ cross-sectional area (CSA) were 11.42 mm (8.6-13.6 mm) and 104.8 mm2 (58-146 mm2). After the procedure, these values were decreased to 6.14 mm (5.7-6.6 mm) and 29.8 mm2 (25-34 mm2) respectively (p = 0.0079). Median pre-plication distensibility (d) and compliance (C) were 7.87 mm2/mmHg (2.4-22.69 mm2/mmHg) and 190.56 mm3/mmHg (70.9-502.8 mm3/mmHg). After the procedure, these values decreased to 1.5 mm2/mmHg (0.7-2.2 mm2/mmHg) and 52.17 mm3/mmHg (21.9-98.7 mm3/mmHg) respectively (p = 0.0317). No intraoperative events were observed. Endoscopically, all valves were felt to be transitioned from a Hill grade 3 (normal state for the animal model) to a Hill grade 1 at the procedure completion. A hybrid laparoendoscopic approach is a feasible alternative for performing intragastric procedures with the assistance of conventional laparoscopic instruments; especially in cases where the intervention location limits the access to standard endoscopy or where endoscopic technology is inadequate. Further evaluation is planned in survival models and clinical trials.

Restrictive pulmonary dysfunction is associated with vertebral fractures and bone loss in elderly postmenopausal women.

Association between lung function and bone metabolism remains controversial. We found that impaired lung function was associated with vertebral fractures and bone loss in Japanese postmenopausal women. While vertebral deformities would impair lung function, respiratory dysfunction might in turn increase fracture risk, suggesting a complex bidirectional interaction. INTRODUCTION: Association between bone metabolism and pulmonary function in the general population is controversial. The aim of this study was to investigate relationship between lung and bone parameters in elderly postmenopausal women. METHODS: One hundred and six postmenopausal women (75.6 ± 8.0 years old) who underwent spirometric tests were examined for prevalent vertebral fractures, bone mineral density (BMD), bone metabolic markers, and other metabolic indices such as urinary pentosidine. RESULTS: Multivariable logistic regression analyses revealed that forced vital capacity (FVC) (OR = 0.063, 95% CI: 0.011-0.352, p = 0.002) and urinary pentosidine (OR = 1.067, 95% CI: 1.020-1.117, p = 0.005) were associated with the presence of vertebral fractures after adjustment for height loss, age, and BMD at femoral neck. Moreover, vital capacity (VC) or FVC as well as body mass index and age was among independent determinants of BMD after adjustment for height loss and the number and grade of vertebral fractures in forced multiple linear regression analysis (VC: ß = 0.212, p = 0.021, FVC: ß = 0.217, p = 0.031). Urinary pentosidine was negatively correlated with pulmonary function parameters such as FVC and forced expiratory volume in 1 s (FEV1.0), although these correlations appeared dependent on age. CONCLUSIONS: Diminished FVC was associated with prevalent vertebral fractures and decreased BMD in Japanese postmenopausal women without apparent pulmonary diseases. Mechanism of such association between pulmonary function and bone status remains to be determined.

Independent association of bone mineral density and trabecular bone score to vertebral fracture in male subjects with chronic obstructive pulmonary disease.

Osteoporosis is a major comorbidity of chronic obstructive pulmonary disease (COPD), but the mechanism of bone fragility is unknown. We demonstrated that trabecular bone score, a parameter of bone quality, was associated with systemic inflammation and was a significant determinant of vertebral fracture independent of bone mineral density. INTRODUCTION: COPD is a major cause of secondary osteoporosis. However, the mechanism of bone fragility is unclear. We previously reported that vertebral fracture was highly prevalent in male COPD patients. To obtain clues to the mechanism of COPD-associated osteoporosis, we attempted to identify determinants of prevalent vertebral fracture in this study. METHODS: In this cross-sectional study, we recruited 61 COPD males and examined pulmonary function, vertebral fractures, bone mineral density (BMD), trabecular bone score (TBS), bone turnover markers, and inflammatory parameters. Determinants of the bone parameters were examined by multivariable analyses. RESULTS: The prevalence of any and grade 2 or 3 fractures was 75.4 and 19.7%, respectively. Osteoporosis and osteopenia defined by BMD were present in 37.7 and 39.3%, respectively. TBS was significantly lower in higher Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages compared to GOLD 1. Multivariable logistic regression analysis revealed that both TBS and BMD were independent determinants of grade 2 or 3 vertebral fractures (OR = 0.271, 95%CI 0.083-0.888, p = 0.031; OR = 0.242, 95%CI 0.075-0.775, p = 0.017) after adjustment for age. Correlates of TBS included age, BMD, high-sensitivity C-reactive protein (hsCRP), pulmonary function parameters, parathyroid hormone, and Tracp-5b. In multivariable regression analysis, hsCRP was the only independent determinant of TBS besides age and BMD. In contrast, independent determinants of BMD included body mass index and, to a lesser extent, 25-hydroxyvitamin D. CONCLUSION: Both BMD and TBS were independently associated with grade 2 or 3 vertebral fracture in COPD male subjects, involving distinct mechanisms. Systemic inflammation, as reflected by increased hsCRP levels, may be involved in deterioration of the trabecular microarchitecture in COPD-associated osteoporosis, whereas BMD decline is most strongly associated with weight loss.

Selection of cellular genetic markers for the detection of infectious poliovirus.

AIMS: Cellular responses of an established cell line from human intestinal epithelial cells (INT-407 cells) against poliovirus (PV) infections were investigated in order to find cellular genetic markers for infectious PV detection. METHODS AND RESULTS: Gene expression profile of INT-407 cells was analysed by DNA microarray technique when cells were infected with poliovirus 1 (PV1) (sabin) at multiplicity of infection of 10-3 and incubated for 12 h. Poliovirus infection significantly altered the gene expressions of two ion channels, KCNJ4 and SCN7A. The expression profile of KCNJ4 gene was further investigated by real-time RT-qPCR, and it was found that KCNJ4 gene was significantly regulated at 24 h postinfection of PV1. CONCLUSIONS: KCNJ4 gene, coding a potassium channel protein, is proposed as a cellular genetic marker for infectious PV detection. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study to show the availability of cellular responses to detect infectious PV. The selection of cellular genetic markers for infectious viruses using DNA microarray and RT-qPCR can be applicable for the other enteric viruses.

Intravenous immunoglobulin contributes to the control of antimelanoma differentiation-associated protein 5 antibody-associated dermatomyositis with palmar violaceous macules/papules.

Autoantibodies to melanoma differentiation-associated protein 5 (MDA5) are associated with a subset of patients with dermatomyositis (DM) who have rapidly progressive interstitial lung disease (RP-ILD) with poor prognosis. Intensive immunosuppressive therapy is initiated before irreversible lung damage can occur; however, there are few lines of evidence for the treatment of RP-ILD. Here, we report three cases of anti-MDA5 antibody-associated DM with RP-ILD in which the patients were treated with combined-modality therapy, including high-dose prednisolone, tacrolimus, intravenous cyclophosphamide and intravenous immunoglobulin (IVIG). In all three cases, serum ferritin levels, which are known to represent the disease activity of RP-ILD, were decreased after IVIG administration. IVIG might contribute to the control of the disease activity of anti-MDA5 antibody-positive DM. Moreover, palmar violaceous macules/papules around the interphalangeal joints, which was observed in all three cases in the incipient stage, might be a useful sign in suggesting a diagnosis of anti-MDA5 antibody-associated DM.

Effects of orthotic therapeutic electrical stimulation in the treatment of patients with paresis associated with acute cervical spinal cord injury: a randomized control trial.

STUDY DESIGN: A randomized controlled trial. OBJECTIVES: To determine the effects of orthotic therapeutic electrical stimulation (TES) on the hand in patients with paresis associated with acute cervical spinal cord injury. SETTING: Spinal Injuries Center, Fukuoka, Japan. METHODS: The study included patients treated for spinal cord injuries (Frankel classification, grades B and C) at our institution within 1 week post injury between May 2011 and December 2014. The patients were allocated randomly to TES and control groups at the time of admission and underwent TES+conventional training or conventional training alone, respectively. Both hands of each patient were treated in the same way. The primary outcome was total passive motion (TPM) of the fingers (degrees). The secondary outcomes were edema (cm) and the upper-extremity motor scores of the International Standards for the Neurological Classification of Spinal Cord Injury (ISNCSCI). After randomization, outcomes were assessed at 1 week, 1 month and 3 months post injury in both groups. RESULTS: Twenty-nine individuals were assessed at 3 months (15, TES; 14, control). There were no significant between-group differences for TPM of the fingers, edema and upper-extremity motor scores at 1 week, 1 month and 3 months after injury, although TPM of the fingers tended to be lower in the control group. CONCLUSIONS: It is unclear from the results of this study whether TES has a therapeutic effect on TPM, edema or the upper-extremity motor score of the ISNCSCI. The results of this study provide useful data for future meta-analyses.

Associations between oral complications and days to death in palliative care patients.

PURPOSE: Adverse oral symptoms gradually appear in advanced cancer patients as the disease progresses. We retrospectively investigated the associations between the incidence of oral problems and the days to death (DTD) in patients receiving palliative care. METHODS: The dental assessment sheets and medical charts of 105 patients who had been admitted into the palliative care unit at our hospital were examined. Case data included evaluations of organic and functional oral conditions at the time of admission for all patients. The cohort was divided into two groups according to the DTD as the short group (<28 days from the time of dental assessment until death) and the long group (≥28 days). We compared the incidences of organic and functional oral problems between these groups. RESULTS: Dry mouth, tongue inflammation, and bleeding spots were significantly more frequent in the short group than in the long group (78 vs. 54% for dry mouth, 67 vs. 46% for tongue inflammation, 35 vs. 14% for bleeding spots, respectively; p < 0.05). Tongue coating and candidiasis were comparable between the two groups. Dysphagia was significantly more common in the short group (43%) than in the long group (20%) (p = 0.01), as was assistance with oral health care (76 vs. 50%) (p = 0.01). CONCLUSIONS: Our findings suggest that, during palliative care, oral complications appear more frequently when the DTD period is shorter. These symptoms may be useful indicators when deciding on the proper timing of intensive oral care intervention to decrease oral problems and pain in terminally ill patients.

Longitudinal association of dentition status with dietary intake in Japanese adults aged 75 to 80 years.

Limited information is available on the temporal association between dentition status and dietary intake. The aim of this 5-year prospective cohort study was to investigate whether impaired dentition was associated with subsequent decline in dietary intake in older Japanese adults. Two hundred and eighty-six community-dwelling Japanese individuals, all aged 75 years at baseline, were included in the study. Functional tooth units (FTUs), defined as a pair of opposing natural or prosthetic teeth excluding third molars (range: 0-14), were counted on the basis of baseline dental examinations. Individuals with ≤5 FTUs were defined as having impaired dentition. Dietary intake was assessed at baseline and 5 years later, using a validated dietary questionnaire. Robust regression analyses were used to evaluate the differences in change in dietary intake between participants with and without impaired functional dentition, after adjustment for potential confounders. Sixty-one study participants (21·3 %) were defined as having impaired dentition. Overall, mean values for all estimated dietary variables (energy, nutrients and food groups) declined over time. Notably, individuals with impaired dentition demonstrated a significantly (P < 0·05) greater degree of decline in the intake of multiple nutrients (protein, sodium, potassium, calcium, vitamin A, vitamin E and dietary fibre) and food groups (vegetable and meat) than those without impaired dentition, after adjusting for potential confounders. The results of this study describe the temporal association of impaired dentition with the decline in selected nutrient and food group intake among older Japanese adults.

Changes in standing body sway of pregnant women after long-term bed rest.

Pregnant women tend to fall and increased body postural instability, namely body sway, may be one of the causative factors. We had a clinical impression that pregnant women after long-term bed rest tend to fall. We hypothesised that such women may show increased body sway, which we attempted to determine. Pregnant women (n = 161) were divided into three groups: (i) women with preterm labour after 2-week bed rest, (ii) those after 4-week bed rest, and (iii) those without bed rest or preterm labour. Body sway was analysed using stabilometry, that is, computed analysis of movement of the centre of gravity. The 3 groups fundamentally showed the same stabilometric measurements. Women with oedema showed greater medial-lateral sway than those without it. Factors other than oedema yielded no differences in stabilometric parameters. Long-term bed rest fundamentally did not increase body sway to the extent that stabilometry could reveal it. It may be prudent to consider that pregnant women with oedema tend to fall.

Metastasis of extra-ampullary duodenal adenocarcinoma to the uterine cervix.

Secondary metastatic tumours of the uterine cervix are rare. There have been no reports of duodenal cancer metastasizing to the uterine cervix. Here we present a rare case of an extra-ampullary duodenal adenocarcinoma that has metastasized to the uterine cervix. The patient was a 71-year-old woman who had surgery for an extra-ampullary duodenal adenocarcinoma five years previously. Follow-up examination revealed a suspicious right ovarian mass and nodules in the cervix and posterior fornix of the vagina. Biopsies suggested squamous cell carcinoma in the cervix and adenocarcinoma in the fornix. Intraoperatively, the right ovary was enlarged and peritoneal disseminations were found in the pouch of Douglas and the sigmoid colon mesentery. Histopathology of the subsequent hysterectomy and bilateral salpingo-oophorectomy specimen revealed a cervical squamous cell carcinoma categorized as pT1b1. Adenocarcinoma infiltration into the ovaries, uterine cervix and vagina, with vascular involvement was detected. Immunohistochemistry revealed the tumour in the cervix and ovaries to be positive for CK7, MUC5AC and MUC6, and immunonegative for CK20, CDX2, Pax8, ER, MUC2 and CD10, similar to the original duodenal adenocarcinoma. This case illustrates the difficulty in making a preoperative diagnosis of metastatic adenocarcinoma in the uterine cervix with a coexisting primary cervical squamous cell carcinoma. The absence of atypia in cervical glandular cells and immunohistochemical profiling of the adenocarcinoma clusters helped to reach a final diagnosis. This is the first report of an extra-ampullary duodenal adenocarcinoma metastasis to the uterine cervix.

Living near a freeway is associated with lower bone mineral density among Mexican Americans.

UNLABELLED: We hypothesized that chronic exposures to traffic combustion products may lower bone mineral density (BMD). We found that proximity to freeways was associated with reduced BMD. Our findings suggest that traffic-related pollution may contribute to the occurrence of osteopenia and osteoporosis. INTRODUCTION: Adults residing in rural areas have been linked with higher BMD. We aimed to determine if this difference is due in part to air pollution by examining the relationships between traffic metrics and ambient air pollution with total body and pelvic BMD. METHODS: Mexican American adults (n = 1,175; mean 34 years; 72 % female) who had participated in the BetaGene study of air pollution, obesity, and insulin resistance were included in this analysis. Total body and pelvic BMD were estimated using dual-energy X-ray absorptiometry. Traffic and ambient air pollutant exposures were estimated at residences using location and ambient monitoring data. Variance component models were used to analyze the associations between residential distance to the nearest freeway and ambient air pollutants with BMD. RESULTS: Residential proximity to a freeway was associated with lower total body BMD (p-trend = 0.01) and pelvic BMD (p-trend = 0.03) after adjustment for age, sex, weight, and height. The adjusted mean total body and pelvic BMD in participants living within 500 m of a freeway were 0.02 and 0.03 g/cm(2) lower than participants living greater than 1,500 m from a freeway. These associations did not differ significantly by age, sex, or obesity status. Results were similar after further adjustment for body fat and weekly physical activity minutes. Ambient air pollutants (NO2, O3, and PM2.5) were not significantly associated with BMD. CONCLUSIONS: Traffic-related exposures in overweight and obese Mexican Americans may adversely affect BMD. Our findings indicate that long-term exposures to traffic may contribute to the occurrence of osteoporosis and its consequences.

HOMA and Matsuda indices of insulin sensitivity: poor correlation with minimal model-based estimates of insulin sensitivity in longitudinal settings.

AIMS/HYPOTHESIS: Little is known about the performance of surrogates in assessing changes in insulin sensitivity over time. This report compared updated HOMA of insulin sensitivity (HOMA2-%S) and the Matsuda index from OGTTs with minimal model-based estimates of insulin sensitivity (SI) from frequently sampled IVGTTs (FSIGTs) in longitudinal settings and cross-sectional settings. METHODS: Two longitudinal studies were used: one a natural observational study in which 338 individuals were followed for a median of 4 years; one a clinical treatment study in which 97 individuals received pioglitazone treatment and were followed for 1 year. Pairs of OGTTs and FSIGTs were performed at baseline and follow-up. Correlations were computed. Impact of measurement uncertainty was investigated through simulation studies. RESULTS: Correlations between HOMA2-%S and SI from baseline or follow-up data were in the range reported previously (0.61-0.69). By contrast, correlations for changes over time were only 0.35-0.39. The corresponding correlations between the Matsuda index and SI were 0.66-0.72 for cross-sectional data and 0.40-0.48 for longitudinal change. Correlations for changes were significantly lower than the cross-sectional correlations in both studies (p < 0.03). Simulation results demonstrated that the reduced correlations for change were not explained by error propagation, supporting a real limitation of surrogates to fully capture longitudinal changes in insulin sensitivity. CONCLUSIONS/INTERPRETATION: HOMA and Matsuda indices derived from cross-sectional data should be used cautiously in assessing longitudinal changes in insulin sensitivity.