A method for evaluating systems of epidemiological surveillance

Epidemiological surveillance is the systematic collection, analysis and dissemination of health data for the planning, implementation and evaluation of public health programmes. Established surveillance systems should be regularly reviewed on the basis of explicit criteria of usefulness, cost and quality; systems should be modified as a result of such review. Attributes of quality include: (i) sensitivity, (ii) specificity, (iii) representativeness, (iv) timeliness, (v) simplicity, (vi) flexibility and (vii) acceptability. To date, evaluation of surveillance systems has been limited in scope and content. The evaluation method proposed in this article offers an organized approach to the evaluation of epidemiological surveillance systems. The usefulness of a surveillance system is measured by whether it leads to prevention or control or a better understanding of adverse health events. The measure can be qualitative, in terms of the subjective views of those using the system, or quantitative in terms of the impact of surveillance data on policies, interventions or the occurrence of a health event. The cost of a system includes indirect as well as direct costs, and should be measured in relation to the benefits obtained, such as reduction of medical-care expenses and of time lost from work. All elements of the system should be included in the cost: data collection, analysis and dissemination. The sensitivity of a surveillance system is its ability to detect health events (completeness of reporting). Its specificity is inversely proportional to the number of false positives it reports. Reports of a disease that do not meet the case definition are false positives, and may result in resources being wasted in investigating them.(ABSTRACT TRUNCATED AT 250 WORDS)     

Considerations in the choice of sutures for wound closure of the genitourinary tract

The ideal suture for use within the urinary tract should maintain its tensile strength until wound repair is satisfactory and then it should undergo rapid total absorption without promoting stone formation. The bladder has a great potential for repair, attaining 100 per cent of the strength of the unwounded tissue in 14 to 21 days. Braided synthetic absorbable sutures appear to be suited ideally for closure of incised wounds of a urinary conduit. They maintain their tensile strength for approximately 21 days, during which time the healing tissues regain strength rapidly. Because sutures are foreign bodies and have access to urine, they may serve as a nidus for stone formation. Several factors that have been identified as important determinants of foreign body urolithiasis include the presence of urine, urine volume and pH, infection, physical and chemical configuration of the foreign body, and animal species. The incidence of suture urolithiasis is related directly to the duration in which the sutures are present in the urinary tract. Consequently, absorbable sutures are preferred over nonabsorbable sutures for closure of wounds of the urinary conduit. In the absence of infection braided synthetic absorbable sutures have distinct advantages over gut sutures for closure of urinary tract wounds. They are absorbed by nonenzymatic hydrolysis in a predictable manner with limited inflammatory response. In contrast, gut sutures have an unpredictable absorption rate by enzymatic degradation and elicit an exaggerated inflammatory response. Because infected urine, especially Proteus species, accelerates the degradation of absorbable synthetic sutures to a greater degree than gut sutures, wound closure in the presence of infection should be accomplished with the absorbable natural fiber suture. Nonabsorbable sutures or staples should not be used in the urinary tract because they predictably promote urolithiasis.     

Costello syndrome: Clinical phenotype,genotype, and management guidelines

Costello syndrome (CS) is a RASopathy caused by activating germline mutations in HRAS. Due to ubiquitous HRAS gene expression, CS affects multiple organ systems and individuals are predisposed to cancer. Individuals with CS may have distinctive craniofacial features, cardiac anomalies, growth and developmental delays, as well as dermatological, orthopedic, ocular, and neurological issues; however, considerable overlap with other RASopathies exists. Medical evaluation requires an understanding of the multifaceted phenotype. Subspecialists may have limited experience in caring for these individuals because of the rarity of CS. Furthermore, the phenotypic presentation may vary with the underlying genotype. These guidelines were developed by an interdisciplinary team of experts in order to encourage timely health care practices and provide medical management guidelines for the primary and specialty care provider, as well as for the families and affected individuals across their lifespan. These guidelines are based on expert opinion and do not represent evidence‐based guidelines due to the lack of data for this rare condition.     

Mycoplasma hyopneumoniae increases intracellular calcium release in porcine ciliated tracheal cells

We investigated the effects of intact pathogenic Mycoplasma hyopneumoniae, nonpathogenic M. hyopneumoniae, and Mycoplasma flocculare on intracellular free Ca2+ concentrations ([Ca2+]i) in porcine ciliated tracheal epithelial cells. The ciliated epithelial cells had basal [Ca2+]i of 103 +/- 3 nM (n = 217 cells). The [Ca2+]i increased by 250 +/- 19 nM (n = 47 cells) from the basal level within 100 s of the addition of pathogenic M. hyopneumoniae strain 91-3 (300 microg/ml), and this increase lasted approximately 60 s. In contrast, nonpathogenic M. hyopneumoniae and M. flocculare at concentrations of 300 microg/ml failed to increase [Ca2+]i. In Ca2+-free medium, pathogenic M. hyopneumoniae still increased [Ca2+]i in tracheal cells. Pretreatment with thapsigargin (1 microM for 30 min), which depleted the Ca2+ store in the endoplasmic reticulum, abolished the effect of M. hyoneumoniae. Pretreatment with pertussis toxin (100 ng/ml for 3 h) or U-73122 (2 microM for 100 s), an inhibitor of phospholipase C, also abolished the effect of M. hyopneumoniae. The administration of mastoparan 7, an activator of pertussis toxin-sensitive proteins G(i) and G(o), increased [Ca2+]i in ciliated tracheal cells. These results suggest that pathogenic M. hyopneumoniae activates receptors that are coupled to G(i) or G(o), which in turn activates a phospholipase C pathway, thereby releasing Ca2+ from the endoplasmic reticulum. Thus, an increase in Ca2+ may serve as a signal for the pathogenesis of M. hyopneumoniae.     

Increased production of proinflammatory cytokines following infection with porcine reproductive and respiratory syndrome virus and Mycoplasma hyopneumoniae

Induction of the proinflammatory cytokines interleukin-1 (IL-1) (alpha and beta), IL-6, IL-8, IL-10, IL-12, and tumor necrosis factor alpha (TNF-alpha) in pulmonary alveolar macrophages (PAMs) was assessed following experimental infection with porcine reproductive and respiratory syndrome virus (PRRSV) and/or Mycoplasma hyopneumoniae by using in vivo and in vitro models. The in vivo model consisted of pigs infected with PRRSV and/or M. hyopneumoniae and necropsied at 10, 28, or 42 days postinfection. Pigs infected with both pathogens had a greater percentage of macroscopic lung lesions, increased clinical disease, and slower viral clearance than pigs infected with either pathogen alone. The pigs infected with both PRRSV and M. hyopneumoniae had significantly increased levels of mRNA for many proinflammatory cytokines in PAMs collected by bronchoalveolar lavage (BAL) at all necropsy dates compared to those in uninfected control pigs. Increased levels of IL-1beta, IL-8, IL-10, and TNF-alpha proteins in BAL fluid, as measured by enzyme-linked immunosorbent assay, confirmed the increased cytokine induction induced by the pathogens. An in vitro model consisted of M. hyopneumoniae-inoculated tracheal ring explants cultured with PRRSV-infected PAMs. PAMs were harvested at 6 or 15 h postinfection with either or both pathogens. The in vitro study detected increased IL-10 and IL-12 mRNA levels in PAMs infected with PRRSV at all time periods. In addition, IL-10 protein levels were significantly elevated in the culture supernatants in the presence of M. hyopneumoniae-inoculated tracheal ring explants. The increased production of proinflammatory cytokines in vivo and in vitro associated with concurrent M. hyopneumoniae and PRRSV infection may play a role in the increased rates of pneumonia associated with PRRSV infection. The increased levels of IL-10 may be a possible mechanism that PRRSV and M. hyopneumoniae use to exacerbate the severity and duration of pneumonia induced by PRRSV and modulate the respiratory immune response.