An actuatable soft reservoir modulates host foreign body response.

The performance of indwelling medical devices that depend on an interface with soft tissue is plagued by complex, unpredictable foreign body responses. Such devices-including breast implants, biosensors, and drug delivery devices-are often subject to a collection of biological host responses, including fibrosis, which can impair device functionality. This work describes a milliscale dynamic soft reservoir (DSR) that actively modulates the biomechanics of the biotic-abiotic interface by altering strain, fluid flow, and cellular activity in the peri-implant tissue. We performed cyclical actuation of the DSR in a preclinical rodent model. Evaluation of the resulting host response showed a significant reduction in fibrous capsule thickness (P = 0.0005) in the actuated DSR compared with non-actuated controls, whereas the collagen density and orientation were not changed. We also show a significant reduction in myofibroblasts (P = 0.0036) in the actuated group and propose that actuation-mediated strain reduces differentiation and proliferation of myofibroblasts and therefore extracellular matrix production. Computational models quantified the effect of actuation on the reservoir and surrounding fluid. By adding a porous membrane and a therapy reservoir to the DSR, we demonstrate that, with actuation, we could (i) increase transport of a therapy analog and (ii) enhance pharmacokinetics and time to functional effect of an inotropic agent. The dynamic reservoirs presented here may act as a versatile tool to further understand, and ultimately to ameliorate, the host response to implantable biomaterials.

Complete genome sequence of the marine Rhodococcus sp. H-CA8f isolated from Comau fjord in Northern Patagonia, Chile.

Rhodococcus sp. H-CA8f was isolated from marine sediments obtained from the Comau fjord, located in Northern Chilean Patagonia. Whole-genome sequencing was achieved using PacBio RS II platform, comprising one closed, complete chromosome of 6,19 Mbp with a 62.45% G + C content. The chromosome harbours several metabolic pathways providing a wide catabolic potential, where the upper biphenyl route is described. Also, Rhodococcus sp. H-CA8f bears one linear mega-plasmid of 301 Kbp and 62.34% of G + C content, where genomic analyses demonstrated that it is constituted mostly by putative ORFs with unknown functions, representing a novel genetic feature. These genetic characteristics provide relevant insights regarding Chilean marine actinobacterial strains.

Characterizing the hippocampal theta's response to carbachol; using a complete septo-hippocampal preparation / Caracterización de la respuesta theta del hipocampo al carbacol en una preparación septo-hipocámpica completa

Abstract: The present study describes the pharmacological analysis of the effects of carbachol, a cholinergic agonist, on hippocampal theta activity. Knowing that this activity is critically related to cognitive function and altered in patients with neurodegeneration, pharmacological efforts aiming to directly modulate hippocampal theta activity becomes of central importance. In a recently developed complete septo-hippocampal preparation, carbachol elicited significant theta power enhancement with 1 μM. Concentrations under 1 μM and over 2 μM carbachol caused significant reduction in the power of hippocampal theta activity. Carbachol effects were completely blocked with the cholinergic antagonist scopolamine. At the experimental level, it is the first time the direct action of a cholinergic agonist is evaluated in the septo-hippocampal pathway completely isolated. However, carbachol as a cholinergic agonist is a drug with a certain level of nonspecific response. That is why to correct this experimental limitation, we used scopolamine (cholinergic antagonist) which allowed us to corroborate the effects on the cholinergic pathway. In summary, electrophysiological assays demonstrated an effective concentration range of carbachol specifically modulating hippocampal theta activity.

Resumen: El presente estudio describe el análisis farmacológico de los efectos de carbacol, un agonista colinérgico, sobre la actividad theta del hipocampo. Sabiendo que esta actividad está críticamente relacionada con la función cognitiva y alterada en pacientes con neurodegeneración, los esfuerzos farmacológicos destinados a modular directamente la actividad theta del hipocampo se vuelven de gran importancia. En una preparación completa que contiene la región septal media conectada al hipocampo, desarrollada recientemente, 1 μM de carbacol provocó un incremento significativo a nivel de potencia en la actividad theta del hipocampo. Las concentraciones menores de1 μM y mayores a 2 μM causaron una reducción significativa en la potencia de la actividad theta. Los efectos del carbacol fueron completamente bloqueados con la escopolamina, antagonista colinérgico. A nivel experimental, es la primera vez que se evalúa la acción directa de un agonista colinérgico en la vía septo-hipocámpica completamente aislada. Sin embargo, el carbacol como agonista colinérgico es un fármaco que presenta cierto nivel de respuesta inespecífica. Es por eso que para corregir esta limitante experimental, se utilizó escopolamina (antagonista colinérgico) lo que nos permitió corroborar los efectos sobre la vía colinérgica. En resumen, nuestros estudios electrofisiológicos demostraron un intervalo de concentración eficaz del carbacol que modula específicamente la actividad theta del hipocampo.

Percutaneous dilatation of biliary strictures through the afferent limb of a modified Roux-en-Y choledochojejunostomy or hepaticojejunostomy.

BACKGROUND: This report is a 13-year prospective evaluation of percutaneous balloon dilatation of benign biliary strictures through the subcutaneous or subfascially positioned afferent limb of a choledocho or hepaticojejunostomy in 30 patients. DATA SOURCE: Twenty-seven strictures developed after a common duct injury sustained at the time of cholecystectomy, two after hepatectomy reconstruction for trauma and one following a gastrectomy. Twelve injuries (40%) were recognized at operation. Of the 18 patients where the injury was unrecognized at the time of operation, 8 had not been reoperated at the time of referral, 7 had late repairs by the referring physician, and 3 had late repairs at our institution. The follow-up is 1 to 13 years. RESULTS: There has been 1 late death and 6 patients are lost alive. The jejunal-limb was accessed 50 times with two minor and no major complications. There have been two parajejunal hernia repairs, but there have not been any reoperations for recurrent biliary strictures. CONCLUSIONS: Benign biliary strictures can be effectively managed by repeat balloon dilatations thru the afferent limb of a choledocho or hepaticojejunostomy, thus eliminating the need for repeat surgical interventions.

The role and application of the balanced scorecard in healthcare quality management.

To connect practices, outcomes, quality, value, and costs, healthcare organizations must start using a balanced scorecard. A balanced scorecard is a set of measures that reveals the interdependency of the organization, its employees, and its patients. It thus serves as a balanced perspective on the organization for senior management to use in designing, developing, deploying, and directing the strategic plan, consistent with total quality management principles.

Value-based cost management: the foundation of a balanced performance measurement system.

Healthcare organizations need critical performance measures if they are to lead, manage, and operate effectively. Traditional financial measures or report cards on patient satisfaction and clinical outcomes are insufficient, however. Value-based cost management directly links cost accounting, processes, clinical outcomes, and patient and employee satisfaction through organizational, work environment, and financial relations measures. These measures address three levels of performance: strategic, diagnostic, and operational. Their linkages identify value in three areas: business-related financial and operational measures; employee-related measures such as those related to satisfaction and well-being; and learning and patient-related measures linked to clinical outcomes, satisfaction, and population.

Linking costs and quality improvement to clinical outcomes through added valued.

A byproduct of outcome measures is the provision of financial benefit to the healthcare providers while ensuring healthcare access and quality to the patient. Consequently, a framework for measuring outcomes must integrate the "customer's perspective" of perceiving value of the services provided, the "provider's perspective" of acting as the patient's fiduciary, and the "business's perspective" of achieving net income. Value-based cost management (VBCM) accomplishes this integration by linking several measures with three financial tools: activity-based costing, value-added analysis, and cost of quality. This article illustrates the use and benefit of VBCM to the laboratory as a partner in the delivery of healthcare services with an example of chest pain triage.

Neurologic outcomes after cardiac resuscitation.

The purpose of this research utilization article is to familiarize cardiovascular nurses with the Brain Resuscitation Clinical Trials (BRCTs) I and II and discuss the application of these trials to nursing practice. The BRCTs are a series of studies that examine the effects of selected interventions on neurologic outcome after cardiac arrest.

Results of the CLMA membership survey on laboratory information systems.

This article presents the results of the CLMA membership survey concerning Laboratory Information Systems. A variety of factors are discussed, including purchase and maintenance cost of systems, user satisfaction, staffing requirements, processor location and control, applications installed, and interfacing to the Hospital Information System.

Proficiency testing from a total quality management perspective.

Public concern over increasing health-care costs plus dramatized testing errors, has resulted in CLIA '88 with its more stringent rules governing laboratory performance. The purpose of the 1990 U.S. Health Care Financing Administration Final Rules for Proficiency Tests is to separate the quality laboratory from the poorly performing one. From the perspective of total quality management, the customer (patient) defines quality as virtually error-free test results. The current proficiency testing format defeats this. Its effective purpose is not to identify quality laboratories but to shut down the most prolific laboratories--regardless of their quality. There are two reasons for this. First, the proficiency testing format is incomplete: it is missing a minimum frequency criterion. Second, the data for determining the quality of a laboratory's performance (the degree of error-free results) are not being used. I propose a solution based on continuous improvement that promotes voluntarism, favors the quality laboratory, and reduces federal regulation.

Chemometrics: measurement reliability.

Applying the principles of chemometrics can lead to development of a powerful, simple, comprehensive system for characterizing measurement reliability of analytical processes. The system described here consists of a format for specifications, definitions, and decision rules for evaluating and comparing analytical processes. Two cases illustrate its advantages over the use of precision, accuracy, total error, and regression statistics for such evaluations.

Medical utility frequency.

Judging the medical acceptability and comparing the medical utility of laboratory methods requires standards for reproducibility with regard to medical performance. A completely general and flexible performance standard for reproducibility consists of the reproducibility criterion, the allowable error, and the concentration value. Neither precision, accuracy, nor total error correctly addresses this standard. The medical utility frequency of a method does do so, however, its use making method evaluation and comparison simple, completely flexible, and exact.