Incidence of fractures compared to cardiovascular disease and breast cancer: the Women's Health Initiative Observational Study

To compare the absolute risk of fracture to the risk of other conditions by race/ethnicity, we studied 83,724 women, aged 70-79. The projected number of fractures was similar to or exceeded the combined number of cardiovascular events and breast cancers. Osteoporosis prevention efforts should target women of all ethnicities.

INTRODUCTION

The relative risk of fracture is lower in non-white compared to white women but the absolute risk of fracture in comparison to other common chronic conditions is uncertain.

METHODS

We performed a prospective cohort study of 83,724 women, age 50-79 years. Cardiovascular disease (CVD), invasive breast cancer and all fractures were identified over an average of 7.7 +/- 2.6 years.

RESULTS

The incidence of fracture, breast cancer, stroke and CVD varied across ethnicity. The annualized (%) incidence of fracture was greatest in whites (2.4%) and American Indians (2.8%) and lowest among blacks (1.3%). The majority of hip fractures occurred in white women. The projected number of women who will experience a fracture in one year exceeded the combined number of women who would experience invasive breast cancer or a broad category of CVD events in all ethnic groups except blacks. In 10,000 black women, an estimated 153 women would experience CVD, and 35 women, breast cancer compared to 126 women expected to fracture in one year.

CONCLUSION

The annual risk of suffering a fracture is substantial in women of all ethnicities. Osteoporosis prevention efforts should target all women irrespective of their race/ethnic backgrounds.

Na+ binding to meizothrombin desF1

Meizothrombin is the physiologically active intermediate generated by a single cleavage of prothrombin at R320 to separate the A and B chains. Recent evidence has suggested that meizothrombin, like thrombin, is a Na(+)-activated enzyme. In this study we present the first X-ray crystal structure of human meizothrombin desF1 solved in the presence of the active site inhibitor PPACK at 2.1 A resolution. The structure reveals a Na(+) binding site whose architecture is practically identical to that of human thrombin. Stopped-flow measurements of Na(+) binding to meizothrombin desF1 document a slow phase of fluorescence change with a k(obs) decreasing hyperbolically with increasing [Na(+)], consistent with the existence of three conformations in equilibrium, E*, E and E:Na(+), as for human thrombin. Evidence that meizothrombin exists in multiple conformations provides valuable new information for studies of the mechanism of prothrombin activation.

CEACAM1 and the regulation of mucosal inflammation

Inflammatory bowel disease (IBD) is characterized by unrestrained T-cell activation that results in the production of a variety of inflammatory cytokines and other mediators. Understanding the mechanisms of T-cell regulation is therefore of significant importance to IBD and other forms of dysregulated-mucosal inflammation. An area that is of significant interest are the cell autonomous mechanisms of T-cell regulation through proteins that have natural inhibitory functions when expressed on T lymphocytes. One such molecule is carcinoembryonic antigen cell adhesion molecule 1 (CEACAM1). CEACAM1 is primarily an activation-induced cell-surface molecule that functions as a co-inhibitory receptor. Homophilic ligation of CEACAM1 on T cells leads to a signaling mechanism, which results in inhibition of a broad range T-cell functions. CEACAM1 therefore represents a new potential therapeutic target in the treatment of IBD.

Medication-induced upper gastrointestinal tract injury

Medication-induced upper gastrointestinal (GI) tract injuries are probably fairly common, yet these injuries are rarely documented in pathology reports. Since these injuries often manifest as non-specific histological changes, making a definitive diagnosis of medication-induced injury can be challenging. Three types of evidence can assist in the establishment of a diagnosis: specific histological patterns, the presence of medication fragments in tissue, and clinical data. Histological patterns may reflect specific tissue responses to medication effects or medication toxicity. Morphological clues of medication use such as pill fragments and crystal deposition may be visible within the tissue itself. Clinical data, including medication history, endoscopic findings, and predisposing conditions can alert the pathologist to situations where medication-induced injury should merit a high ranking on the differential diagnosis list. Except for rare cases where characteristic histological changes can be diagnostic, clinical correlation is essential when diagnosing medication-induced injuries. In this review, key features of the most commonly encountered medication-induced upper GI tract injuries are briefly discussed, and a practical guide to assist the practicing pathologist in the recognition and diagnosis of these injuries is provided.

Optical coherence tomographic characteristics and surgical outcome of eyes with myopic foveoschisis

AIM

To describe the optical coherence topographic (OCT) characteristics and outcome of vitrectomy with triamcinolone acetonide (TA)-assisted epiretinal tissue removal and gas tamponade in eyes with myopic foveoschisis (MF).

METHODS

We examined 101 myopic eyes, and the OCT characteristics of 18 eyes (18%) with an MF were studied. Six eyes underwent vitrectomy with TA-assisted epiretinal tissue removal and gas tamponade. The postoperative outcome measures were best-corrected visual acuity (BCVA), resolution of the MF as determined by OCT, and complications.

RESULTS

OCT scans showed an isolated MF in three (17%) eyes, and the MF were associated with two or more macular anomalies in 15 (83%) eyes. A foveal detachment was found in 13 (72%), lamellar macular hole in 4 (22%), and a tractional epimacular membrane in 11 (61%) of the 18 eyes. Six eyes underwent surgery, in which the epiretinal tissue was made visible by intravitreal TA and completely removed. The median BCVA significantly improved from 20/400 preoperatively (range, 20/1000-20/160) to 20/160 postoperatively (range, 20/200-20/40; P=0.03, Wilcoxon signed-rank test). The mean VA improved by 5.6 lines. OCT showed a complete reattachment of the fovea in four (67%) eyes and a small subfoveal or parafoveal detachment in two (33%) eyes.

CONCLUSIONS

MF is commonly observed in highly myopic eyes and most are associated with one or more macular anomalies. Vitrectomy with TA-assisted complete removal of all tractional premacular structures followed by gas tamponade resulted in good visual and anatomical outcomes for treating MF.

Quantum nature of a nuclear phase transition

At finite temperatures and low densities, nuclei may undergo a phase change similar to a classical liquid-gas phase transition. Temperature is the control parameter while density and pressure are the conjugate variables. In the nucleus the difference between the proton and neutron concentrations acts as an additional order parameter, for which the symmetry potential is the conjugate variable. We present experimental results which reveal the N/Z dependence of the phase transition and discuss possible implications of these observations in terms of the Landau free energy description of critical phenomena.

A Point Process Approach to Assess Dynamic Baroreflex Gain

Evaluation of arterial baroreflex in cardiovascular control is an important topic in cardiology and clinical medicine. In this paper, we present a point process approach to estimate the dynamic baroreflex gain in a closed-loop model of the cardiovascular system. Specifically, the inverse Gaussian probability distribution is used to model the heartbeat interval, whereas the instantaneous mean is modulated by a bivariate autoregressive model that contains the previous R-R intervals and systolic blood pressure (SBP) measures. The instantaneous baroreflex gain is estimated in the feedback loop with a point process filter, while the RR→SBP feedforward frequency response gain can be estimated by a Kalman filter. The proposed estimation approach provides a quantitative assessment of interacting heartbeat dynamics and hemodynamics. We validate our approach with real physiological signals and evaluate the proposed model with established goodness-of-fit tests.

Application of radiation hybrid in gene mapping

Radiation hybrid (RH) mapping technique was exploited to determine chromosome locations of 26 human novel full length cDNAs recently cloned. All these cDNA clones were isolated from human cord blood CD (+) (34) cells and may be related to regulation of hematopoiesis. 23 genes were successfully mapped to chromosomal positions, while RH analyses were not possible in the remaining 3 cases. RH technique is indeed a powerful tool for mapping novel cDNA sequences due to its rapidity, precision, convenience and reproducibility.