Multisite time-series studies versus cohort studies: methods, findings, and policy implications

Time-series and cohort studies of air pollution on human health have advanced greatly our understanding of the effects of air pollution on health since the earliest studies. Availability of large national databases and progress in computational tools and statistical methods have made possible the estimation of national average pollution effects and the exploration of potential sources of heterogeneity in the effects of air pollution across countries or regions. Interpretation of the findings needs to account for several challenges, including confounding and the resolution of seemingly conflicting results from time-series and cohort studies. This article presents an overview of the time-series and cohort studies' approaches for estimating the relative risk of mortality from particulate air pollution and discusses the statistical issues and challenges inherent in each of these studies. We also discuss policy relevant summaries in air pollution epidemiology, approaches for estimating the impact of particulate matter on mortality from time-series and cohort studies, and research opportunities under the National Medicare Cohort Study (NMCS).     

Oral manifestations during herpes virus infection. Case report

The infections due to herpes viruses are widely spread, people being every day at high risk of contamination starting early age. The characteristic of the herpes virus infection consists of a symptom less evolution following the prime infection. As for any other herpetic infection, episodes infection exacerbation is due to some determining factors. Clinical symptom in herpes virus infection varies according to the virus type, age of the patient and site. Oral signs and symptoms are numerous, extremely intense and often, difficult to diagnose. Progressing in so many ways and being diagnosed and treated by so many medical specialties it is difficult to evaluate the actual number of cases. Consequently it is mandatory to train dentists in order to be able to accurately diagnose and treat the herpetic infection and to prevent nosocomial cross infections in dental office.     

The hot skull sign on bone scans of obese patients resulting from disparate soft tissue attenuation

We have frequently observed diffusely increased skull activity on bone scans of obese patients, who do not have evidence of metabolic or metastatic bone disease. Skull activity of 25 obese patients were compared to that of age and sex-matched nonobese 25 patients visually and quantitatively. The results clearly indicated that diffusely increased skull activity is significantly more common on bone scans of obese patients because of disparate attenuation of overlying soft tissues. This knowledge will help obviate the need for additional radiologic and/or laboratory tests in search of other conditions associated with hot skull, ie, Paget's disease and metabolic bone disorders such as renal osteodystrophy and primary hyperparathyroidism.     

Anesthesia for obstetric patients with Gaucher disease: survey and review

Pregnancy and delivery in patients with non-neuronopathic Gaucher disease, whether treated with enzyme replacement or untreated, are usually uncomplicated. Various factors may influence mode of delivery, vaginal or cesarean section, as well as type of anesthesia, general or regional, used during delivery. This retrospective review was intended to highlight some of the practical issues relating to obstetric anesthetic management, based on a review of the literature and experiences from a large referral clinic for Gaucher disease. In the past decade, there were 16 deliveries in 11 women in our institution. There were five normal vaginal deliveries, two vacuum extractions, one placental extraction, and eight cesarean sections. Platelet counts were 27-215 x 10(9)/L. Two spontaneous deliveries and one vacuum extraction were performed under epidural anesthesia; two other women having vaginal deliveries and one vacuum extraction were given i.v. analgesia; the fifth was given i.v. patient-controlled analgesia. The placental extraction was performed under general anesthesia. Seven of the women having cesarean deliveries received spinal anesthesia; the breech presentation required general anesthesia. There were no anesthesia-related side effects or complications, although there were some instances of post-partum bleeding irrespective of enzyme therapy. Gaucher disease affects multiple organs and can be a challenge to the anesthesiologist. Based on this survey we suggest that anesthetic management requires particular attention to hematological parameters before delivery. A multidisciplinary approach and extensive communication among obstetrician, hematologist and anesthesiologist is required to anticipate the possibility of post-partum hemorrhage, and preclude skeletal damage.     

The pattern of expression of protease-activated receptors (PARs) during early trophoblast development

Human fetal development depends on the ability of the embryo to gain access to the maternal circulation. Thus, specialized stem cells of the newly formed placenta, trophoblast, invade the uterus and its arterial network to establish an efficient feto-maternal molecular exchange. To accomplish this task, trophoblast differentiation during the first trimester of pregnancy involves cell proliferation, invasion, and extracellular matrix (ECM) remodelling. Trophoblast invasion shares many features with tumour cell invasion, with the distinction that it is strictly spatially and temporally controlled. We have previously demonstrated that PAR1, the first member of the protease-activated receptor (PAR) family, plays a central role in tumour cell invasion. In the present study we have examined the pattern of expression of PAR1 and other PAR family candidates during early human placental development. We show that PAR1 and PAR3 are highly and spatially expressed between the 7th and 10th weeks of gestation but not at the 12th week and thereafter. Likewise, high expression levels of PAR1 and PAR3 were observed in the cytotrophoblast cells of complete hydatidiform mole as compared to minimal levels in normal age-matched placenta. Together, our data suggest the involvement of PAR1 and PAR3 in restricted and unrestricted pathological trophoblast invasion.     

Fluorescein angiography in diabetic retinopathy

Fluorescein angiography plays an important role in diagnosis, classification and management of diabetic retinopathy. He paper presents angiographic aspects of some patients from "LASER OPTICS" office. An accurate and early diagnosis, and also the evaluation of laser treatment need fluorescein angiography as a useful method in the follow-up of diabetic patient.     

Processing emotional body expressions: state-of-the-art

Processing emotional body expressions has become recently an important topic in affective and social neuroscience along with the investigation of facial expressions. The objective of the study is to review the literature on emotional body expressions in order to discuss the current state of knowledge on this topic and identify directions for future research. The following electronic databases were searched: PsychINFO, Ebsco, ERIC, ProQuest, Sagepub, and SCOPUS using terms such as “body,” “bodily expression,” “body perception,” “emotions,” “posture,” “body recognition” and combinations of them. The synthesis revealed several research questions that were addressed in neuroimaging, electrophysiological and behavioral studies. Among them, one important question targeted the neural mechanisms of emotional processing of body expressions to specific subsections regarding the time course for the integration of emotional signals from face and body, as well as the role of context in the perception of emotional signals. Processing bodily expression of emotion is similar to processing facial expressions, and the holistic processing is extended to the whole person. The current state-of-the-art in processing emotional body expressions may lead to a better understanding of the underlying neural mechanisms of social behavior. At the end of the review, suggestions for future research directions are presented.     

New polymer-halloysite hybrid materials-potential controlled drug release system

New hybrid materials based on a natural host (halloysite), biodegradable polymer (poly(vinyl alcohol)) and diphenhydramine hydrochloride as drug were synthesized and tested as a potential controlled drug delivery system. The formation of these hybrid materials was proved using different characterization methods like Spectroscopic techniques (FTIR, XPS and UV-vis), thermogravimetrical analysis and scanning electron microscopy (SEM). The hybrid materials exhibit different features regarding the drug release. In vitro drug release tests showed that there are several factors which exhibit a strong influence on the drug release rate. Thus the initial drug concentration used at the hybrid materials synthesis, the presence of a polymer in the hybrid composition and the pH value of the release medium are the most important factors.