Background and aims: To investigate the impact of obesity on joint pain, we examined the association of body mass index (BMI) with joint pain. Methods: 351 community-dwelling Japanese women aged 40–85 years were asked about joint pain at specific joints, and height and weight were measured. Logistic regression analysis was used to evaluate BMI and other potential predictors of joint pain. Results: BMI was positively associated with knee pain, but not with pain at other specific pints, after adjusting for age. The association of BMI with knee pain remained significant after adjustment for an additional covariate (physical activity). We also examined the associations of age, BMI, and regular physical activity with joint pain at any site, in the arm, in the leg, or in the back. Independently of age and regular physical activity, BMI was positively associated with joint pain in the leg, but not with pain at any site, in the arm or in the back. No significant association of physical activity with joint pain at any site, in the arm, in the leg or in the back was found. Conclusions: Knee pain was associated with greater BMI. This finding supports previous longitudinal studies, suggesting that some knee pain could be prevented by avoidance of excess weight, if the association is causative. However, the association was not very strong; thus, it is likely that many cases of knee pain cannot be avoided by weight reduction only, and may require other interventions.

Encapsidation of duplex DNA by bacteriophages represents an extreme case of genome condensation, reaching near-crystalline concentrations of DNA. The HK97 system is well suited to study this phenomenon in view of the detailed knowledge of its capsid structure. To characterize the interactions involved, we combined calorimetry with cryo-electron microscopy and native gel electrophoresis. We found that, as in other phages, HK97 DNA is organized in coaxially wound nested shells. When DNA-filled capsids (heads) are scanned in buffer containing 1 mm Mg2+, DNA melting and capsid denaturation both contribute to the complex thermal profile between 82 degrees C and 96 degrees C. In other conditions (absence of Mg2+ and lower ionic strength), DNA melting shifts to lower temperatures and the two events are resolved. Heads release their DNA at temperatures well below the onset of DNA melting or capsid denaturation. We suggest that, on heating, the internal pressure increases, causing the DNA to exit-probably via the portal vertex-while the capsid, although largely intact, sustains local damage that leads to an earlier onset of thermal denaturation. Heads differ structurally from empty capsids in the curvature of their protein shell, a change attributable to outwards pressure exerted by the DNA. We propose that this transition is sensed by the portal that is embedded in the capsid wall, whereupon the structure of the portal and its interactions with terminase, the packaging enzyme, are altered, thus signaling that packaging is at or approaching completion. Published by Elsevier Ltd.

For a wastewater collection system, the maximum volume that can be attained with an inline storage pipe is shown to occur when the pipe diameter is chosen to be 2/3 of the thickness of soil profile available for burial of the storage pipe, irrespective of pipeline slope.

Scanning calorimetry combined with cryo-electron microscopy affords a powerful approach to investigating hierarchical interactions in multi-protein complexes. Calorimetry can detect the temperatures at which certain interactions are disrupted and cryo-EM can reveal the accompanying structural changes. The procapsid of bacteriophage HK97 (Prohead I) is a 450 Å-diameter shell composed of 60 hexamers and 12 pentamers of gp5, organized with icosahedral symmetry. Gp5 consists of the N-terminal Δ-domain (11 kDa) and gp5∗ (31 kDa): gp5∗ forms the contiguous shell from which clusters of Δ-domains extend inwards. At neutral pH, Prohead I exhibits an endothermic transition at 53 °C with an enthalpy change of 14 kcal/mole (of gp5 monomer). We show that this transition is reversible. To capture its structural expression, we incubated Prohead I at 60 °C followed by rapid freezing and, by cryo-EM, observed a capsid species 10% larger than Prohead I. At 11 Å resolution, visible changes are confined to the gp5 hexamers. Their Δ-domain clusters have disappeared and are presumably disordered, either by unfolding or dispersal. The gp5∗ hexamer rings are thinned and flattened as they assume the conformation observed in Expansion Intermediate I, a transition state of the normal, proteolysis-induced, maturation pathway. We infer that, at ambient temperatures, the hexamer Δ-domains restrain their gp5∗ rings from switching to a lower free energy, EI-I-like, state; above 53°, this restraint is overcome. Pentamers, on the other hand, are more stably anchored and resist this thermal perturbation.

The International Society for Medical Publication Professionals (ISMPP) is an independent, nonprofit professional association with members from the pharmaceutical, medical device, and biotechnology industries; publication planning and medical communications companies; academia; and medical journal staffs, including editors and publishers. ISMPP's mission is to support the educational needs of medical publication professionals by providing a forum to facilitate awareness and development of best practices in publication planning and implementation, and fostering consensus policies related to medical publishing. This position statement reflects our concern about the current climate of mistrust regarding the use of professional medical writers in the preparation of manuscripts. We acknowledge the skills and training of medical writing professionals and support their role in working with research teams to develop clear and concise manuscripts in a timely fashion. Further, we support complete and transparent disclosure of the role of the medical writer and the source of funding for the writing initiative in order to build awareness of, and trust in, the appropriate use of medical writing professionals. ISMPP endorses use of the contributorship model, which offers detailed information on the roles of all who participated in planning, conducting, developing, and publishing medical research. Further, we propose that this model be integrated into the standard operating procedures of the diverse organizations that comprise our membership because the responsibility for authorship disclosure is shared by sponsors, authors, study investigators, and medical writers. Finally, we commend the many organizations that have worked to increase recognition and understanding of the legitimate role of the medical writer, and are eager to work in concert with them to ensure the rigorous maintenance of all ethical standards for reporting the results of medical research.

We investigated the thermodynamic basis of HK97 assembly by scanning calorimetry and cryo-electron microscopy. This pathway involves self-assembly of hexamers and pentamers of the precursor capsid protein gp5 into procapsids; proteolysis of their N-terminal A-domains; expansion, a major conformational change; and covalent crosslinking. The thermal denaturation parameters convey the changes in stability at successive steps in assembly, and afford estimates of the corresponding changes in free energy. The procapsid represents a kinetically accessible local minimum of free energy. In maturation, it progresses to lower minima in a cascade punctuated by irreversible processes ("locks"), i.e. proteolysis and crosslinking, that lower kinetic barriers and prevent regression. We infer that Delta-domains not only guide assembly but also restrain the procapsid from premature expansion; their removal by proteolysis is conducive to initiating expansion and to its proceeding to completion. We also analyzed the mutant E219K, whose capsomers reassemble in vitro into procapsids with vacant vertices called "whiffleballs". E219K assemblies all have markedly reduced stability compared to wild-type gp5 (Delta T-p similar to -7 degrees C to -10 degrees C) where T-p is the denaturation temperature). As the mutated residue is buried in the core of gp5, we attribute the observed reduction in stability to steric and electrostatic perturbations of the packing of side-chains in the subunit interior. To explain the whiffleball phenotype, we suggest that these effects propagate to the capsomer periphery in such a way as to differentially affect the stability or solubility of dissociated pentamers, leaving only hexamers to reassemble. Published by Elsevier Ltd.

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2005

AbstractOBJECTIVE: To develop a simple and easy-to-use tool for identifying osteoporotic women (femoral neck bone mineral density [BMD] T-scores ≤−2.5) in Latin America. DESIGN: Retrospective study involving review of medical records. SETTING: Osteoporosis clinics in 6 Latin American countries. PATIENTS: Postmenopausal women ages ≥50 in Latin America who had femoral neck BMD measurements. MEASUREMENTS AND MAIN RESULTS: A risk index was developed from 1.547 patients based on least square regression using age, weight, history of fractures, and other variables as predictors for BMD T-score. The final model was simplified by reducing the number of predictors; sensitivity and specificity were evaluated before and after reducing the number of predictors to assess performance of the index. The final model included age, weight, country, estrogen use, and history of fractures as significant predictors for T-score. The resulting scoring index achieved 91% sensitivity and 47% specificity. Simplifying the index by using only age and weight yielded similar performance (sensitivity, 92%; specificity, 45%). Three risk categories were identified based on OsteoRisk, the index using only age and body weight: high-risk patients (index <=−2; 65.6% were osteoporotic), moderate-risk patients (−21; 8% were osteoporotic). Similar results were seen in a validation sample of 279 women in Brazil. CONCLUSION: Age and weight alone performed well for predicting the risk of osteoporosis among postmenopausal women. The OsteoRisk is an easy-to-use tool that effectively targets the vast majority of osteoporotic patients in Latin America for evaluation with BMD.

In HK97 capsid maturation, structural change (‘expansion’) is accompanied by formation of covalent crosslinks, connecting residue K169 in the ‘E‐loop’ of each subunit with N356 on another subunit. We show by complementation experiments with the K169Y mutant, which cannot crosslink, that crosslinking is an essential function. The precursor Prohead‐II passes through three expansion intermediate (EI) states en route to the end state, Head‐II. We investigated the effects of expansion and crosslinking on stability by differential scanning calorimetry of wild‐type and K169Y capsids. After expansion, the denaturation temperature (Tp) of K169Y capsids is slightly reduced, indicating that their thermal stability is not enhanced, but crosslinking effects a major stabilization (ΔTp, +11°C). EI‐II is the earliest capsid to form crosslinks. Cryo‐electron microscopy shows that for both wild‐type and K169Y EI‐II, most E‐loops are in the ‘up’ position, 30 Å from the nearest N356: thus, crosslinking in EI‐II represents capture of mobile E‐loops in ‘down’ positions. At pH 4, most K169Y capsids remain as EI‐II, whereas wild‐type capsids proceed to EI‐III, suggesting that crosslink formation drives maturation by a Brownian ratchet mechanism.

Osteoporosis in men is a largely neglected condition in Asia (and elsewhere), despite the fact that one-third of hip fractures occur in men. Moreover, access to bone mineral density (BMD) measurements is limited in many areas of Asia, and inexpensive methods of targeting high risk patients for BMD measurements would be valuable. We have developed a simple clinical assessment tool to identify high risk Asian men for BMD measurements. Information on risk factors was collected from 420 community-dwelling adult Chinese men aged 50 years and above using a structured questionnaire, and the ability of these risk factors to identify subjects with femoral neck BMD T score ≤ −2.5 was assessed. Multiple regression analysis and item reduction yielded a final clinical risk assessment tool based on only age and weight, similar to the Osteoporosis Self-assessment Tool for Asians (OSTA), described previously for Asian women. The OSTA values of ≤ −1 had a sensitivity of 81% and specificity of 66%, and the area under the receiver operating characteristics curve was 0.83. The index was validated in another sample of 356 men with a sensitivity of 82% and specificity of 67 %, and an AUC of 0.85. The usefulness of OSTA was further compared to calcaneal quantitative bone ultrasound (QUS) in the validation sample of 356 men. The optimal cutoff T score of −1.2 for QUS yielded sensitivity and specificity values of 75 and 67%, respectively. The AUC for QUS was 0.79. Combining OSTA and QUI gave a sensitivity of 88% and specificity of 66% to identify men with low BMD at the femoral neck, and an AUC of 0.86 which was statistically not different from either OSTA or QUI alone. We conclude that OSTA is a simple and effective clinical risk assessment tool for identifying not only female but also male subjects at increased risk of osteoporosis, and its use could facilitate the appropriate and more cost-effective use of bone densitometry in developing countries.

OBJECTIVE:To compare bone mineral density (BMD) and bone turnover changes after therapy withdrawal in postmenopausal women treated with alendronate or estrogen-progestin.DESIGN:In this randomized, blinded, multinational, placebo-controlled trial, 1,609 healthy postmenopausal women ages 45 to 59 years were assigned to receive alendronate, placebo, or open-label estrogen-progestin (conjugated equine estrogens plus medroxyprogesterone acetate or a cyclic regimen of 17 beta-estradiol, norethisterone acetate and estradiol). Of the original women, one third after year 2 and one third after year 4 were switched from alendronate to placebo, while remaining blinded to treatment assignment. The women taking estrogen-progestin in years 1 to 4 were followed off therapy in years 5 and 6. BMD at the lumbar spine and hip and biochemical markers of bone turnover were measured.RESULTS:The treatment groups described in the current report represent 860 women at baseline; 481 women entered year 5, and 430 completed 6 years. BMD steadily decreased in the placebo group during all 6 years. In contrast, spine and hip BMD increased during the first 4 years in the groups receiving daily continuous alendronate 5 mg and estrogen-progestin. During years 5 and 6, BMD decreased at the lumbar spine -2.42% (95% CI = -4.10, -0.74) and total hip -1.09% (-2.60, 0.41) in the group previously treated with alendronate 5 mg for 4 years. In comparison, large BMD decreases were observed at the spine [-7.69% (-8.96, -6.41)] and total hip [-5.16% (-6.30, -4.01)] among women who had received estrogen-progestin for 4 years.CONCLUSION:Alendronate produces greater residual skeletal effects than estrogen-progestin after therapy discontinuation.

Tn7 transposition requires the assembly of a nucleoprotein complex containing four self‐encoded proteins, transposon ends, and target DNA. Within this complex, TnsC, the molecular switch that regulates transposition, and TnsA, one part of the transposase, interact directly. Here, we demonstrate that residues 504–555 of TnsC are responsible for TnsA/TnsC interaction. The crystal structure of the TnsA/TnsC(504–555) complex, resolved to 1.85 Å, illustrates the burial of a large hydrophobic patch on the surface of TnsA. One consequence of sequestering this patch is a marked increase in the thermal stability of TnsA as shown by differential scanning calorimetry. A model based on the complex structure suggested that TnsA and a slightly longer version of the cocrystallized TnsC fragment (residues 495–555) might cooperate to bind DNA, a prediction confirmed using gel mobility shift assays. Donor DNA binding by the TnsA/TnsC(495–555) complex is correlated with the activation of the TnsAB transposase, as measured by double‐stranded DNA cleavage assays, demonstrating the importance of the TnsA/TnsC interaction in affecting Tn7 transposition.

According to the "amyloid backbone" model of Ure2p prionogenesis, the N-terminal domain of Ure2p polymerizes to form an amyloid filament backbone surrounded by the C-terminal domains. The latter domains retain their native glutathione-S-transferase (GST)-like fold but are sterically inactivated from their regulatory role in nitrogen catabolism. We have tested this model by differential scanning calorimetry of soluble and filamentous Ure2p and of soluble C-terminal domains, combined with electron microscopy. As predicted, the C-terminal domains respond to thermal perturbation identically in all three states, exhibiting a single endotherm at 76 degrees C. In contrast, no thermal signal was associated with the N-terminal domains: in the soluble state of Ure2p, because they are unfolded; in the filamentous state, because their robust amyloid conformation resists heating to 100 degrees C.

Short-term changes in biochemical markers of bone turnover (bone markers) have been suggested as predictors of long-term response in bone mass during antiresorptive treatment. In the Danish cohort (n = 306) of the Early Postmenopausal Intervention Cohort (EPIC) Study (n = 1609) of oral alendronate (ALN) for prevention of postmenopausal osteoporosis, bone markers (urine C-telopeptides of type I collagen (uCTX), urine N-telopeptide cross-links of type I collagen (uNTX), serum total osteocalcin measured by ELISA [total OC (ELISA)], and serum total osteocalcin measured by RIA [total OC (RIA)]) were measured at 6-month intervals. The correlation between 6-month change in uCTX and 4-year change in spine and hip bone mineral density (BMD) was r = −0.41 and r = −0.42, respectively (P < 0.001). The corresponding values for the other bone markers were r = −0.53 and r = −0.42 (uNTX), r = −0.46 and r = −0.47 [total OC (ELISA)], and r = −0.43 and r = −0.41 [total OC (RIA)], all P < 0.001. ROC curves were used to analyse the ability of the bone markers to predict a change in spine BMD greater than 0%. The best performance [defined as the maximum value of (sensitivity plus specificity)] was found at the cut-off values of a −29% change from baseline in uCTX, a −45% change from baseline in uNTX, a −13% change from baseline in total OC (ELISA), and a −15% change from baseline in total OC (RIA). At these values the corresponding sensitivity was 66% (uCTX), 76% (uNTX), 70% [total OC (ELISA)], and 83% [total OC (RIA)]. The specificity was 80% (uCTX), 75% (uNTX), 71% [total OC (ELISA)], and 55% [total OC (RIA)]. The positive predictive value (PPV) was 82% (uCTX), 80% (uNTX), 77% [total OC (ELISA)], and 71% [total OC (RIA)]. The negative predictive value (NPV) was 64% (uCTX), 70% (uNTX), 64% [total OC (ELISA)], and 71% [total OC (RIA)]. In conclusion, the bone markers predicted a change in spine BMD greater than 0% with a high PPV and specificity. There was a trend toward better performance in this respect for the bone resorption markers.

Osteoporosis is a growing problem in Asia, and early identification of at risk subjects for preventive measures is likely the most cost-effective method for managing this disease in developing countries. Patients with low bone mineral density (BMD) have a high risk of future fracture. However, access to BMD measurements is limited in many areas of Asia, and inexpensive methods of targeting high-risk patients for BMD measurements would be valuable. We compared two methods, a simple clinical risk assessment tool, the Osteoporosis Self-assessment Tool for Asians (OSTA), and quantitative bone ultrasound (QUS) in identifying subjects with low BMD by DXA in 722 southern Chinese postmenopausal women recruited from the community in Hong Kong. Using the published cutoff value of –1 (versus 0 or higher) for OSTA to identify subjects with femoral neck BMD T -score ≤−2.5, basing on our local population peak young mean value, the sensitivity and specificity was 88% and 54% respectively. The optimal cutoff T -score of –2.35 for QUS yielded sensitivity and specificity values of 81% and 65%, respectively. The AUC for QUS was 0.78, which was not significantly different from that of 0.80 for OSTA. Both OSTA and QUS correlated significantly with BMD at the femoral neck (0.62 and 0.36, respectively, P both <0.001). When these cut-off values were used to identify subjects with either lumbar spine or femoral neck BMD T -score ≤−2.5, the sensitivity and specificity was 79% and 60%, respectively, for OSTA, and 69% and 70%, respectively, for QUS. Combining QUS with OSTA improved the sensitivity to 91%, but the specificity was reduced to 44%. We conclude that the simple clinical risk assessment tool OSTA is a free and effective method for identifying subjects at increased risk of osteoporosis, and its use could facilitate the appropriate and more cost-effective use of bone densitometry in developing countries.

BACKGROUND:It has been reported that there is an inverse association between osteoarthritis (OA) and osteoporosis. However, the relationship of bone mass to OA in a Japanese population whose rates of OA are different from Caucasians remains uncertain.METHODS:We studied the association of appendicular bone mineral density (second metacarpal; mBMD) and quantitative bone ultrasound (calcaneus; stiffness index) with knee and hand OA among 567 Japanese community-dwelling women. Knee and hand radiographs were scored for OA using Kellgren-Lawrence (K/L) scales. In addition, we evaluated the presence of osteophytes and of joint space narrowing. The hand joints were examined at the distal and proximal interphalangeal (DIP, PIP) and first metacarpophalangeal/carpometacarpal (MCP/CMC) joints.RESULTS:After adjusting for age and body mass index (BMI), stiffness index was significantly higher in women with K/L scale, grade 3 at CMC/MCP joint compared with those with no OA. Adjusted means of stiffness index and mBMD were significantly higher in women with definite osteophytes at the CMC/MCP joint compared to those without osteophytes, whereas there were no significant differences for knee, DIP and PIP joints. Stiffness index, but not mBMD, was higher in women with definite joint space narrowing at the CMC/MCP joint compared with those with no joint space narrowing.CONCLUSIONS:Appendicular bone mass was increased with OA at the CMC/MCP joint, especially among women with osteophytes. Our findings suggest that the association of peripheral bone mass with OA for knee, DIP or PIP may be less clearcut in Japanese women than in other populations.