Epidemiology and control and curable sexually transmitted diseases: opportunities and problems

BACKGROUND: Despite the availability of safe and effective treatment, infection with bacterial sexually transmitted diseases persists at a high prevalence in many populations. GOAL: To review the difficulties of parameter estimation when a cure is readily available and to explore the impact of different treatment and screening strategies that might maximize the benefits of using available treatments. STUDY DESIGN: A standard deterministic model for the spread of a bacterial sexually transmitted disease that causes symptomatic and asymptomatic infections, in which the population is stratified according to sex and sexual activity, is further stratified into two host groups to enable the modeling of different treatment and screening strategies. RESULTS: In the presence of a core group, if an infection has a high transmission probability, then screening for asymptomatic infections has a short-lived benefit. Repeated screening is slightly better if it is not restricted to a fraction of the at-risk population, but targeting of high-risk groups should be effective. Screening to treat asymptomatic infections in men could be beneficial if a substantial fraction of cases remain asymptomatic. CONCLUSIONS: After the initial gains achieved through treating symptomatic infections, further reductions in the prevalence of infections can be achieved by finding asymptomatic infections. However, these gains are difficult to achieve, especially in the case of gonorrhea. Because men are likely to have an asymptomatic chlamydial infection, screening of men for chlamydia should be worthwhile.     

皮肤激光与光子:进展与现状

1治疗理论1.1选择性光热作用原理选择性光热作用原理(theory of selective photothermolysis)是1983年Anderson等提出来的,其精     

Lumps and bumps in neonates and infants

There are many developmental abnormalities that may appear in the neonate and in infants when critical steps in embryogenesis fail. These steps are often not fatal but can lead to significant morbidity for those patients affected. A logical approach is needed in addressing both the diagnostic and therapeutic issues that arise when caring for these patients, as various lesions will warrant an observational approach, and others may require imaging studies or definitive surgical intervention. Additionally, there are other "lumps and bumps" that are seen in the neonatal and infantile age groups that include malignancies and cutaneous neoplasms with associated systemic sequelae.     

Understanding and Evaluating Systematic Reviews and Meta-analyses

A systematic review is a summary of existing evidence that answers a specific clinical question, contains a thorough, unbiased search of the relevant literature, explicit criteria for assessing studies and structured presentation of the results. A systematic review that incorporates quantitative pooling of similar studies to produce an overall summary of treatment effects is a meta-analysis. A systematic review should have clear, focused clinical objectives containing four elements expressed through the acronym PICO (Patient, group of patients, or problem, an Intervention, a Comparison intervention and specific Outcomes). Explicit and thorough search of the literature is a pre-requisite of any good systematic review. Reviews should have pre-defined explicit criteria for what studies would be included and the analysis should include only those studies that fit the inclusion criteria. The quality (risk of bias) of the primary studies should be critically appraised. Particularly the role of publication and language bias should be acknowledged and addressed by the review, whenever possible. Structured reporting of the results with quantitative pooling of the data must be attempted, whenever appropriate. The review should include interpretation of the data, including implications for clinical practice and further research. Overall, the current quality of reporting of systematic reviews remains highly variable.     

Human T lymphocytes and mast cells differentially express and regulate extra- and intracellular CXCR1 and CXCR2

CXCL8 plays a major role in cell recruitment to sites of inflammation. Apart from neutrophils, little is known, however, about the cellular distribution and regulation of CXCL8 receptors in cells involved in acquired and adaptive immune responses. In previous studies, we have demonstrated the extracellular expression and function of CXCR1/2 on mast cells and also detected an intracellular pool of CXCR1/2. Here, we have addressed the question of receptor regulation during stimulation of human mast cells (HMC-1 cell line) and have studied T cells in comparison. Cell permeabilization was performed to detect both surface and possible intracellular receptor pools. HMC-1 cells stained positive for both receptors on the cell surface (CXCR1, 50%; CXCR2, 51%) and also after cell permeabilization (CXCR1, 86%; CXCR2, 74%). Similarly, T cells exhibited both cell-surface receptor expression (CXCR1, 30%; CXCR2, 23%) and higher total receptor expression (CXCR1, 50%; CXCR2, 36%), although overall values were lower than that in HMC-1 cells. On immunoblot, molecular weights of extra- and intracellular receptors on mast cells were the same, excluding altered receptor glycosylation. On stimulation with phorbol 12-myristate 13-acetate plus calcium ionophore, a time-dependent decrease of surface-membrane receptors was observed in both cell types, while total receptor remained the same, suggesting that receptor shedding is not involved. The kinetics of membrane receptor internalization and replenishment differed for the two cell types. Furthermore, receptor internalization was associated with decreased F-actin polymerization, a basic prerequisite for cell migration. These findings demonstrate for the first time the expression of extra- and intracellular CXCR1/2 receptors on T cells and delineate the dynamics of CXCR1/2 receptors on mast cells and T cells. Furthermore, they suggest a cell-type-specific and finely tuned regulation of chemokine responses at the receptor level in the context of inflammation.     

Children and newborn skin care and prevention

Neonatal skin suffers a progressive adaptation to the extrauterine environment and special care is needed during this period. This skin is very sensitive, thin and fragile. Immaturity of the epidermal barrier reduces the defense against the excessive proliferation of microbes and makes the skin more vulnerable to trauma and percutaneous drug toxicity. Because of the peculiar characteristics of newborn, infant and children's skin, the use of cosmetic products designed for hygiene and protection requires caution. In order to preserve the integrity of neonatal and child's skin, this article reviewed basic preventive care practices in relation to hygiene, bathing, cleansing agents, topical products and their percutaneous toxicity.