This book clarifies the application of cybernetic ideas, particularly those of Beer's Viable System Model, to organizational diagnosis and design. Readers learn to appreciate the relevance of seeing ...the systemic coherence of the world. The book argues that many of the problems we experience today are routed in our practice of fragmenting that that needs to be connected as a whole. It offers a method to study and design organizations and a methodology to deal with implementation problems. It is the outcome of many years of working experience with government offices as well as with all kinds of public and private enterprises. At a more detailed level this book offers an in depth discussion of variety engineering that is not available either in the primary or secondary literature.
Background Influenza cause a clinical and economic burden for health systems and society. It is necessary to know the cost of the disease in order to perform cost-effectiveness assessments of ...preventive or treatment interventions. Objective Assess the costs of the care of children with influenza in a third level hospital in Mexico. Methods Longitudinal retrospective study based on the review of clinical files of children hospitalized with influenza. The use of resources used during their hospitalization in the emergency room, general ward, or PICU was logged, and the amount of supplies were multiplied by their corresponding prices to calculate the direct medical expenses. Descriptive statistics were used, and a GLM was adjusted in order to assess the effect of the clinical characteristics of the patients on the cost. Goodness of fit tests were performed. Results 132 files were reviewed, out of which 95% were of subjects who had comorbidities. Subjects admitted at the PICU generates the highest cost (mean $29,608.62 USD), when analyzing the total cost summarizing the three clinical areas (Emergency room, general ward and PICU) by age group, the highest cost was for patients over age 10 (mean $49,674.53 USD). Comorbidities increase the cost of hospitalization by $10,000.00 USD. Conclusions Influenza causes a significant financial burden on the health system. Children with comorbidities increase the costs and children over 10 years uses a significant amount of resources and they are not a priority in immunization program. It is necessary to perform studies on the use of resources in the first and second attention levels, which represent the highest incidence of the disease.
Background
CMV remains a frequent complication after liver transplantation. Few studies exist in children reporting the epidemiology and outcomes of CMV after LT with current prevention strategies. ...Our goal is to report the incidence of CMV infection and disease in pediatric LT recipients under preemptive therapy, identify risk factors, complications, and adverse reactions to treatment.
Methods
All pediatric LT recipients from a single center (1998–2018) were included. Antigenemia pp65 (1998–2003) and QNAT or both were used to inform preemptive therapy. Cutoff value for starting treatment was Agpp65 > 10 + cells/200 000 or QNAT >1500 copies/ml or any value in high‐risk recipients (D+/R−).
Results
One hundred eighteen LT were analyzed. CMV infection was detected in 67% of patients, only 44 (37%) required treatment, and 5 (4%) developed CMV disease. All patients responded well to treatment, and no graft or patients were lost to CMV effects. There were no differences in mortality, CMV indirect effects, or other complications between those who required treatment and those who did not. Thirty‐two percent of the patients who received antivirals developed an adverse hematological reaction. Risk factors associated with CMV infection requiring treatment were D+/R− (OR 13.9, p = .01) and fulminant hepatitis (OR 4.8, p = .02).
Conclusions
Preemptive therapy for CMV in children is safe and effective, yields low CMV infection rates that require treatment, and minimal rates of CMV disease, without increasing CMV‐related complications. Using this strategy, 63% of our patients did not receive treatment. Therefore, drug exposure, adverse reactions, and resistance risk were minimized.
The purpose of this paper is to show an application of variety engineering in the social realm (Beer in The heart of enterprise. Wiley, Chichester, 1979, in Brain of the firm. Wiley, Chichester 1981, ...in diagnosing the system for organizations. Wiley, Chichester, 1985). It focuses on reducing environmental complexity by catalysing self-organizing processes (Espejo and Reyes in Organizational systems: managing complexity with the VSM. Springer, London, 2011). This catalysis is based on the use of Sen and Nussbaum’s capabilities approach (Sen in Development as freedom. Oxford University Press, New York, 1999; Nusbaum in Women and human development: the capabilities approach. Cambridge University Press, New York, 2000). By doing this an organization may improve the quality of the relations with their clients by transforming environmental agents into new suppliers. This approach opens a new dimension of social responsibility for organizations. A particular case is presented in which a regional university in Colombia faces the challenge of attending low-income students coming from small municipalities. They designed a strategy to offer low-cost housing and a daily balanced meal without using the university's own resources. Instead, they managed to involve some agents of the community by developing their capabilities. This kind of variety engineering shows the possibility of new forms of social responsibility in universities by incorporating the capabilities approach into their managerial practices. This is something that is currently under study in other universities (Boni et al. in Science and engineering ethics. Springer, London, 2015).
Pseudomonas aeruginosa has different resistant mechanisms including the constitutive MexAB-OprM efflux pump. Single nucleotide polymorphisms (SNPs) in the mexR, nalC, and nalD repressors of this ...efflux pump can contribute to antimicrobial resistance; however, it is unknown whether these changes are mainly related to genetic lineages or environmental pressure. This study identifies SNPs in the mexR, nalC, and nalD genes in clinical and environmental isolates of P. aeruginosa (including high-risk clones). Ninety-one P. aeruginosa strains were classified according to their resistance to antibiotics, typified by multilocus sequencing, and mexR, nalC, and nalD genes sequenced for SNPs identification. The mexAB-oprM transcript expression was determined. The 96.7% of the strains were classified as multidrug resistant. Eight strains produced serine carbapenemases, and 11 strains metallo-β-lactamases. Twenty-three new STs and high-risk clones ST111 and ST233 were identified. SNPs in the mexR, nalC, and nalD genes revealed 27 different haplotypes (patterns). Sixty-two mutational changes were identified, 13 non-synonymous. Haplotype 1 was the most frequent (n = 40), and mainly identified in strains ST1725 (33/40), with 57.5% pan drug resistant strains, 36.5% extensive drug resistant and two strains exhibiting serin-carbapenemases. Haplotype 12 (n = 9) was identified in ST233 and phylogenetically related STs, with 100% of the strains exhibiting XDR and 90% producing metallo-β-lactamases. Haplotype 5 was highly associated with XDR and related to dead when compared to ST1725 and ST233 (RRR 23.34; p = 0.009 and RRR 32.01; p = 0.025). A significant relationship between the mexR-nalC-nalD haplotypes and phylogenetically related STs was observed, suggesting mutational changes in these repressors are highly maintained within genetic lineages. In addition, phylogenetically related STs showed similar resistant profiles; however, the resistance was (likely or partly) attributed to the MexAB-OprM efflux pump in 56% of the strains (only 45.05% showed mexA overtranscription), in the remaining strains the resistance could be attributed to carbapenemases or mechanisms including other pumps, since same SNPs in the repressor genes gave rise to different resistance profiles.
Drug-drug interactions (DDIs) detected in a patient may not be clinically apparent (potential DDIs), and when they occur, they produce adverse drug reactions (ADRs), toxicity or loss of treatment ...efficacy. In pediatrics, there are only few publications assessing potential DDIs and their risk factors. There are no studies in children admitted to emergency departments (ED). The present study estimates the prevalence and describes the characteristics of potential DDIs in patients admitted to an ED from a tertiary care hospital in Mexico; in addition, potential DDI-associated risk factors are investigated.
A secondary analysis of data from 915 patients admitted to the ED of the Hospital Infantil de México "Federico Gómez" was conducted. The Medscape Drug Interaction Checker software was used to identify potential DDIs. The results are expressed as number of cases (%), means (95% CI) and medians (25-75th percentiles). Count data regressions for number of total and severity-stratified potential DDIs were performed adjusting for patient characteristics, number of administered drugs, days of stay, presence of ADRs and diagnoses.
The prevalence of potential DDIs was 61%, with a median of 4 (2-8). A proportion of 0.2% of potential DDIs was "Contraindicated", 7.5% were classified as "Serious", 62.8% as "Significant" and 29.5% as "Minor". Female gender, age, days of stay, number of administered drugs and diagnoses of Neoplasms (C00-D48), Congenital malformations (Q00-Q99), Diseases of the Blood, Blood-forming Organs and Immunity (D50-D89) and Diseases of the nervous system (G00-G99) were significantly associated with potential DDIs.
The prevalence of potential DDIs in the ED is high, and strategies should therefore be established to monitor patients' safety during their stay, in addition to conducting investigations to estimate the real harm potential DDIs inflict on patients.
The management of febrile neutropenia (FN) in pediatric cancer patients has traditionally been conducted in a hospital setting. However, recent evidence has indicated that outpatient management of FN ...can be equally effective compared to inpatient care. Based on this evidence, we conducted a cost-minimization analysis (CMA) specifically focused on pediatric cancer patients in Mexico.BACKGROUNDThe management of febrile neutropenia (FN) in pediatric cancer patients has traditionally been conducted in a hospital setting. However, recent evidence has indicated that outpatient management of FN can be equally effective compared to inpatient care. Based on this evidence, we conducted a cost-minimization analysis (CMA) specifically focused on pediatric cancer patients in Mexico.A piggy-back study was conducted during the execution of a non-inferiority clinical trial that compared outpatient treatment to inpatient treatment for FN in children with cancer. A CMA was performed from a societal perspective using patient-level data. In the previous study, we observed that step-down oral outpatient management of low-risk FN was as safe and effective as inpatient intravenous management. Direct and indirect costs were collected prospectively. The costs were adjusted for inflation and converted to US dollars, with values standardized to July 2022 costs. Statistical analysis using bootstrap methods was employed to obtain robust estimations for decision-making within the Mexican public health care system.METHODSA piggy-back study was conducted during the execution of a non-inferiority clinical trial that compared outpatient treatment to inpatient treatment for FN in children with cancer. A CMA was performed from a societal perspective using patient-level data. In the previous study, we observed that step-down oral outpatient management of low-risk FN was as safe and effective as inpatient intravenous management. Direct and indirect costs were collected prospectively. The costs were adjusted for inflation and converted to US dollars, with values standardized to July 2022 costs. Statistical analysis using bootstrap methods was employed to obtain robust estimations for decision-making within the Mexican public health care system.A total of 117 FN episodes were analyzed, with 60 in the outpatient group and 57 in the inpatient group; however, complete cost data were available for only 115 FN episodes. The analysis revealed an average savings of $1,087 per FN episode managed on an outpatient basis, representing a significant 92% reduction in total cost per FN episode compared to inpatient treatment. Length of hospital stay and inpatient consultations emerged as the primary cost drivers within the inpatient care group.RESULTSA total of 117 FN episodes were analyzed, with 60 in the outpatient group and 57 in the inpatient group; however, complete cost data were available for only 115 FN episodes. The analysis revealed an average savings of $1,087 per FN episode managed on an outpatient basis, representing a significant 92% reduction in total cost per FN episode compared to inpatient treatment. Length of hospital stay and inpatient consultations emerged as the primary cost drivers within the inpatient care group.This CMA demonstrates that the step-down outpatient management approach is cost-saving when compared to inpatient management of FN in pediatric cancer patients. The mean difference observed between the treatment groups provides support for decision-making within the public health care system, as outpatient management of FN allows for substantial cost savings without compromising patient health.CONCLUSIONThis CMA demonstrates that the step-down outpatient management approach is cost-saving when compared to inpatient management of FN in pediatric cancer patients. The mean difference observed between the treatment groups provides support for decision-making within the public health care system, as outpatient management of FN allows for substantial cost savings without compromising patient health.
Background
Bilateral retinoblastoma (Rb) treatment remains a challenge for ophthalmologists and pediatric oncologists despite new therapeutic strategies for eye preservation. The purpose of this work ...is to evaluate treatment outcomes in patients who underwent eye salvage treatment at a single‐center prior to the chemotherapy in situ era.
Procedure
We followed a cohort of 88 consecutive Rb patients diagnosed at Hospital Infantil de México between November 2000 and June 2014. Eye salvage treatment consisted of systemic chemotherapy plus focal therapy planned by a multidisciplinary team. Unresponsive tumors were treated with episcleral brachytherapy and external beam radiotherapy (EBRT).
Results
A total of 96 eyes underwent eye salvaging therapy. Seventy‐eight eyes (81%) were salvaged. Seven patients (8%) required brachytherapy and 34 patients (39%) underwent EBRT. Thirty‐three of 78 preserved eyes (42%) achieved normal visual acuity: 5/27 (20%) in radiated patients and 28/51 (61%) in nonradiated patients. Eight patients developed secondary primary malignancies; however, those treated with EBRT did not have a significantly increased risk when compared with nonirradiated patients (OR: 1.66; P = 0.492). The overall survival rate was 86% (95% CI, 76%‐92%) after a mean follow‐up of 10 years.
Conclusions
Eye preservation, long‐term tumor control, and functional visual acuity could be maintained in many child and adolescent Rb survivors. Our data suggest that ocular radiotherapy can be used as consolidation treatment when other recently developed therapies with potentially fewer side effects are not available. Multidisciplinary management of Rb is mandatory to obtain cancer control during eye salvage treatment.
This paper presents a novel method for modeling a 3-degree of freedom open kinematic chain using quaternions algebra and neural network to solve the inverse kinematic problem. The structure of the ...network was composed of 3 hidden layers with 25 neurons per layer and 1 output layer. The network was trained using the Bayesian regularization backpropagation. The inverse kinematic problem was modeled as a system of six nonlinear equations and six unknowns. Finally, both models were tested using a straight path to compare the results between the Newton–Raphson method and the network training.
Many biological systems use ethylene glycol bis (β-aminoethylether)-
N,
N,
N′,
N′-tetraacetic acid (EGTA) to regulate the free calcium concentration (Ca
2+
free) in the presence of physiological ...levels of free Mg
2+ (Mg
2+
free). Frequently, it is necessary to work at Ca
2+
free beyond EGTA’s buffering capabilities. Therefore, we have developed methods to extend the buffering range by adding nitrilotriacetic acid (NTA) to solutions containing EGTA. This extension results from NTA having a lower
K
dCa
′
than EGTA. Such equilibria are solved by pCa Calculator, a computer program designed to aid in the study of Ca
2+-dependent physiological processes while accounting for the effects of pH, temperature, and ionic strength. With multiple chelators and pH buffers from which to choose, pCa Calculator calculates the total concentration of each species required to achieve specified free concentrations of Ca
2+, ATP, and Mg
2+. The program is intuitive, user-friendly, and flexible enough to fix or vary the Mg-ATP
2− and ionic strength. Moreover, it can account for increases in experimental volume from calcium addition. A comparative analysis is reported for testing solutions in the presence and absence of NTA by measuring the calcium binding affinity of fluorescent cardiac troponin C. These findings demonstrate that EGTA, when used in conjunction with NTA, improves and expands the regulation of free calcium in solution.
PDF
