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Gastroschisis mortality is 75-100% in low-resource settings. In Rwanda, late deaths are often due to sepsis. We aimed to understand the effect of antimicrobial use on survival. We conducted a retrospective review of gastroschisis patients at a tertiary hospital in Kigali, Rwanda between January 2016-June 2019. Demographics, antimicrobial use, microbiology, and outcomes were abstracted. Descriptive and univariate analyses were conducted to assess factors associated with improved survival. Among 92 gastroschisis patients, mortality was 77%(n = 71); 23%(n = 21) died within 48 h. 98%(n = 90) of patients received antibiotics on arrival. Positive blood cultures were obtained in 41%(n = 38). Patients spent 86%(SD = 20%) of their hospital stay on antibiotics and 38%(n = 35) received second-line agents. There was no difference in age at arrival, birth weight, gestational age, silo complications, or antimicrobial selection between survivors and non-survivors. Late death patients spent more total hospital days and post-abdominal closure days on antibiotics (p < 0.001) compared to survivors. There was no difference in the proportion of hospital stay on second-line antibiotics (p = 0.1). CONCLUSION: We identified frequent late deaths, prolonged antibiotic courses, and regular use of second-line antibiotic agents in this retrospective cohort of Rwandan gastroschisis patients. Future studies are needed to evaluate antimicrobial resistance in pediatric surgical patients in Rwanda. WHAT IS KNOWN: ⢠Global disparities in gastroschisis outcomes are extreme, with <4% mortality in high-income settings and 75-100% mortality in low-income settings. ⢠Antimicrobial surveillance data is sparse across Africa, but existing evidence suggests high levels of resistance to first-line antibiotics in Rwanda. WHAT IS NEW: ⢠In-hospital survival for gastroschisis was 23% from 2016-2019 and most deaths occurred late (>48hrs after admission) due to sepsis. ⢠Rwandan gastroschisis patients received prolonged courses of antibiotics and second-line antibiotics were frequently used without culture data, raising concern for antimicrobial resistance.
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Gastrosquisis , Humanos , Niño , Gastrosquisis/complicaciones , Gastrosquisis/tratamiento farmacológico , Estudios Retrospectivos , Rwanda/epidemiología , Pacientes Internos , Antibacterianos/uso terapéuticoRESUMEN
Background: Frailty in older adults has been associated with reduced brain health. However, structural brain signatures of frailty remain understudied. Our aims were: (1) Explore associations between a frailty index (FI) and brain structure on magnetic resonance imaging (MRI). (2) Identify the most important FI features driving the associations. Methods: We designed a cross-sectional observational study from a population-based study (The Irish Longitudinal Study on Aging: TILDA). Participants aged ≥50 years who underwent the wave 3 MRI sub-study were included. We measured cortex, basal ganglia, and each of the Desikan-Killiany regional volumes. Age-and sex-adjusted correlations were performed with a 32-item self-reported FI that included conditions commonly tested for frailty in research and clinical settings. A graph theory analysis of the network composed by each FI item and cortex volume was performed. White matter fiber integrity was quantified using diffusion tensor imaging (DTI). Results: In 523 participants (mean age 69, 49% men), lower cortex and thalamic volumes were independently associated with higher FI. Sensory and functional difficulties, diabetes, polypharmacy, knee pain, and self-reported health were the main FI associations with cortex volume. In the network analysis, cortex volume had a modest influence within the frailty network. Regionally, higher FI was significantly associated with lower volumes in both orbitofrontal and temporal cortices. DTI analyses revealed inverse associations between the FI and the integrity of some association bundles. Conclusion: The FI used had a recognizable but subtle structural brain signature in this sample. Only some FI deficits were directly associated with cortex volume, suggesting scope for developing FIs that include metrics more specifically related with brain health in future aging neuroscience studies.
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Frailty in older adults is associated with greater risk of cognitive decline. Brain connectivity insights could help understand the association, but studies are lacking. We applied connectome-based predictive modeling to a 32-item self-reported Frailty Index (FI) using resting state functional MRI data from The Irish Longitudinal Study on Ageing. A total of 347 participants were included (48.9% male, mean age 68.2 years). From connectome-based predictive modeling, we obtained 204 edges that positively correlated with the FI and composed the "frailty network" characterised by connectivity of the visual network (right); and 188 edges that negatively correlated with the FI and formed the "robustness network" characterized by connectivity in the basal ganglia. Both networks' highest degree node was the caudate but with different patterns: from caudate to visual network in the frailty network; and to default mode network in the robustness network. The FI was correlated with walking speed but not with metrics of global cognition, reinforcing the matching between the FI and the brain connectivity pattern found (main predicted connectivity in basal ganglia).
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Conectoma , Fragilidad , Humanos , Masculino , Anciano , Femenino , Estudios Longitudinales , Fragilidad/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Envejecimiento , Imagen por Resonancia Magnética , Red Nerviosa/diagnóstico por imagenRESUMEN
BACKGROUND: Sarcopenia and orthostatic hypotension are growing age-related health burdens associated with adverse outcomes, including falls. Despite a possible pathophysiological link, the association between the 2 disorders is not well elucidated. We sought to investigate this relationship in The Irish Longitudinal Study on Ageing (TILDA). METHODS: Data from 2 858 participants at wave 3 of TILDA were analyzed. Probable sarcopenia was defined as per the European Working Group on Sarcopenia in Older People revised definition cutoffs (hand grip strength [HGS] <27 kg in men, <16 kg in women, and/or 5-chair stand test [5CST] time >15 seconds). Participants underwent an active stand orthostatic test with continuous blood pressure (BP) monitoring. Multilevel mixed-effects models, controlling for possible confounders, were used to assess the effect of probable sarcopenia by HGS and 5CST criteria on the change in BP after standing. RESULTS: HGS- and 5CST-defined probable sarcopenia were independently associated with an attenuated BP recovery at 10-20 seconds poststand (systolic BP: ß -0.54, p < .001; ß -0.25, p < .001). On average, those meeting HGS probable sarcopenia criteria had a significantly lower BP at 20, 30, and 40 seconds (differences in systolic BP: -5.01 mmHg, -3.68 mmHg, -2.32 mmHg, p < .05 for all). Those meeting 5CST probable sarcopenia criteria had a significant difference in systolic BP at 20 seconds (-1.94 mmHg, p = .002) but not at 30 or 40 seconds. CONCLUSION: Probable sarcopenia had a significant association with delayed orthostatic BP recovery, with HGS-defined probable sarcopenia having a stronger association than 5CST-defined probable sarcopenia. Results support a modest but significant pathophysiological link between probable sarcopenia and orthostatic hypotension.
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Hipotensión Ortostática , Sarcopenia , Masculino , Humanos , Femenino , Anciano , Estudios Longitudinales , Sarcopenia/complicaciones , Sarcopenia/diagnóstico , Sarcopenia/epidemiología , Hipotensión Ortostática/complicaciones , Hipotensión Ortostática/diagnóstico , Hipotensión Ortostática/epidemiología , Fuerza de la Mano , Envejecimiento/fisiología , Hemodinámica/fisiología , Presión SanguíneaRESUMEN
The Sustained Attention to Response Task (SART) is a computer-based go/no-go task to measure neurocognitive function in older adults. However, simplified average features of this complex dataset lead to loss of primary information and fail to express associations between test performance and clinically meaningful outcomes. Here, we combine a novel method to visualise individual trial (raw) information obtained from the SART test in a large population-based study of ageing in Ireland and an automatic clustering technique. We employed a thresholding method, based on the individual trial number of mistakes, to identify poorer SART performances and a fuzzy clusters algorithm to partition the dataset into 3 subgroups, based on the evolution of SART performance after 4 years. Raw SART data were available for 3468 participants aged 50 years and over at baseline. The previously reported SART visualisation-derived feature 'bad performance', indicating the number of SART trials with at least 4 mistakes, and its evolution over time, combined with the fuzzy c-mean (FCM) algorithm, individuated 3 clusters corresponding to 3 degrees of physiological dysregulation. The biggest cluster (94% of the cohort) was constituted by healthy participants, a smaller cluster (5% of the cohort) by participants who showed improvement in cognitive and psychological status, and the smallest cluster (1% of the cohort) by participants whose mobility and cognitive functions dramatically declined after 4 years. We were able to identify in a cohort of relatively high-functioning community-dwelling adults a very small group of participants who showed clinically significant decline. The selected smallest subset manifested not only mobility deterioration, but also cognitive decline, the latter being usually hard to detect in population-based studies. The employed techniques could identify at-risk participants with more specificity than current methods, and help clinicians better identify and manage the small proportion of community-dwelling older adults who are at significant risk of functional decline and loss of independence.
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INTRODUCTION: Neonatal surgical diseases are prime examples of the global disparity in surgical access and outcomes, with survival for conditions like gastroschisis reaching above 95% in high-income settings but usually fatal in low-income settings. This study aims to examine outcomes and predictors of mortality in patients with two specific neonatal surgical conditions that often require early transfer and prolonged inpatient care (gastroschisis and intestinal atresia) at Rwanda's main pediatric referral hospital. METHODS: A single-institution retrospective chart review of neonates with gastroschisis and intestinal atresia was conducted between January 2016 and June 2019. Abstracted data included demographics, referral history, admission interventions, operative details, in-hospital complications, nutrition patterns, length of stay, and mortality. Daily logs were created to evaluate feeding status, infection status, and antibiotic usage. Descriptive and univariate analysis was conducted, with the primary outcome being survival to hospital discharge. RESULTS: A total of 112 patients met inclusion criteria (82% gastroschisis [n = 92] and 18% intestinal atresia [n = 20]). Median age at arrival was 0 d (GS) [IQR 0-1 d] and 8.5 d (IA) [IQR 4-10 d] (P < 0.0001). Survival to discharge was 22.8% (GS) (n = 21) and 60% (IA) (n = 12) with a mean length of stay of 28.3 d (GS) and 18.4 d (IA). The median number of days to initiation of oral feeds was 8.5 d [IQR 7-11] for gastroschisis survivors. CONCLUSIONS: Neonatal surgical conditions that require early transfer and prolonged nutritional intervention are challenging in low-resource settings, but through treatment by a comprehensive pediatric surgical service, improving survival is possible.
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Gastrosquisis , Atresia Intestinal , Niño , Gastrosquisis/complicaciones , Gastrosquisis/cirugía , Hospitalización , Humanos , Recién Nacido , Atresia Intestinal/complicaciones , Atresia Intestinal/epidemiología , Atresia Intestinal/cirugía , Estudios Retrospectivos , Rwanda/epidemiología , Resultado del TratamientoRESUMEN
The quantification of biological age in humans is an important scientific endeavor in the face of ageing populations. The frailty index (FI) methodology is based on the accumulation of health deficits and captures variations in health status within individuals of the same age. The aims of this study were to assess whether the addition of age to an FI improves its mortality prediction and whether the associations of the individual FI items differ in strength. We utilized data from The Irish Longitudinal Study on Ageing to conduct, by sex, machine learning analyses of the ability of a 32-item FI to predict 8-year mortality in 8174 wave 1 participants aged 50 or more years. By wave 5, 559 men and 492 women had died. In the absence of age, the FI was an acceptable predictor of mortality with AUCs of 0.7. When age was included, AUCs improved to 0.8 in men and 0.9 in women. After age, deficits related to physical function and self-rated health tended to have higher importance scores. Not all FI variables seemed equally relevant to predict mortality, and age was by far the most relevant feature. Chronological age should remain an important consideration when interpreting the prognostic significance of an FI.
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The Sustained Attention to Response Task (SART) has been used to measure neurocognitive functions in older adults. However, simplified average features of this complex dataset may result in loss of primary information and fail to express associations between test performance and clinically meaningful outcomes. Here, we describe a new method to visualise individual trial (raw) information obtained from the SART test, vis-à-vis age, and groups based on mobility status in a large population-based study of ageing in Ireland. A thresholding method, based on the individual trial number of mistakes, was employed to better visualise poorer SART performances, and was statistically validated with binary logistic regression models to predict mobility and cognitive decline after 4 years. Raw SART data were available for 4864 participants aged 50 years and over at baseline. The novel visualisation-derived feature bad performance, indicating the number of SART trials with at least 4 mistakes, was the most significant predictor of mobility decline expressed by the transition from Timed Up-and-Go (TUG) < 12 to TUG ≥ 12 s (OR = 1.29; 95% CI 1.14-1.46; p < 0.001), and the only significant predictor of new falls (OR = 1.11; 95% CI 1.03-1.21; p = 0.011), in models adjusted for multiple covariates. However, no SART-related variables resulted significant for the risk of cognitive decline, expressed by a decrease of ≥2 points in the Mini-Mental State Examination (MMSE) score. This novel multimodal visualisation could help clinicians easily develop clinical hypotheses. A threshold approach to the evaluation of SART performance in older adults may better identify subjects at higher risk of future mobility decline.
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Gait speed is a measure of general fitness. Changing from usual (UGS) to maximum (MGS) gait speed requires coordinated action of many body systems. Gait speed reserve (GSR) is defined as MGS-UGS. From a shortlist of 88 features across five categories including sociodemographic, cognitive, and physiological, we aimed to find and compare the sets of predictors that best describe UGS, MGS, and GSR. For this, we leveraged data from 3,925 adults aged 50+ from Wave 3 of The Irish Longitudinal Study on Ageing (TILDA). Features were selected by a histogram gradient boosting regression-based stepwise feature selection pipeline. Each model's feature importance and input-output relationships were explored using TreeExplainer from the Shapely Additive Explanations explainable machine learning package. The mean R a d j 2 (SD) from fivefold cross-validation on training data and the R a d j 2 score on test data were 0.38 (0.04) and 0.41 for UGS, 0.45 (0.04) and 0.46 for MGS, and 0.19 (0.02) and 0.21 for GSR. Each model selected features across all categories. Features common to all models were age, grip strength, chair stands time, mean motor reaction time, and height. Exclusive to UGS and MGS were educational attainment, fear of falling, Montreal cognitive assessment errors, and orthostatic intolerance. Exclusive to MGS and GSR were body mass index (BMI), and number of medications. No features were selected exclusively for UGS and GSR. Features unique to UGS were resting-state pulse interval, Center for Epidemiologic Studies Depression Scale (CESD) depression, sit-to-stand difference in diastolic blood pressure, and left visual acuity. Unique to MGS were standard deviation in sustained attention to response task times, resting-state heart rate, smoking status, total heartbeat power during paced breathing, and visual acuity. Unique to GSR were accuracy proportion in a sound-induced flash illusion test, Mini-mental State Examination errors, and number of cardiovascular conditions. No interactions were present in the GSR model. The four features that overall gave the most impactful interactions in the UGS and MGS models were age, chair stands time, grip strength, and BMI. These findings may help provide new insights into the multisystem predictors of gait speed and gait speed reserve in older adults and support a network physiology approach to their study.
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BACKGROUND: Time to hormonal control after definitive management of hyperthyroidism is unknown but may influence patient and physician decision making when choosing between treatment options. The hypothesis is that the euthyroid state is achieved faster after thyroidectomy than RAI ablation. METHODS: A retrospective review of all patients undergoing definitive therapy for hyperthyroidism was performed. Outcomes after thyroidectomy were compared to RAI. RESULTS: Over 3 years, 217 patients underwent definitive therapy for hyperthyroidism at a county hospital: 121 patients received RAI, and 96 patients underwent thyroidectomy. Age was equivalent (p = 0.72). More males underwent RAI (25% vs 15%, p = 0.05). Endocrinologists referred for both treatments equally (p = 0.82). Both treatments were offered after a minimum 1-year trial of medical management (p = 0.15). RAI patients mostly had Graves (93%), versus 73% of thyroidectomy patients (p < 0.001). Thyroidectomy patients more frequently had eye symptoms (35% vs 13%, p < 0.001), compressive symptoms (74% vs 15%, p < 0.001), or were pregnant/nursing (14% vs 0, p < 0.001). While the thyroidectomy patients had a documented discussion of all treatment modalities, 79% of RAI patients did not have a documented discussion regarding the option of surgical management (p < 0.001). Both treatment groups achieved an euthyroid state (71% vs 65%, p = 0.39). Thyroidectomy patients became euthyroid faster [3 months (2-7 months) versus 9 months (4-14 months); p < 0.001]. CONCLUSIONS: Thyroidectomy for hyperthyroidism renders a patient to an euthyroid state faster than RAI. This finding may be important for patients and clinicians considering definitive options for hyperthyroidism.
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Enfermedad de Graves/terapia , Radioisótopos de Yodo/uso terapéutico , Tiroidectomía , Adulto , Comunicación , Femenino , Enfermedad de Graves/sangre , Enfermedad de Graves/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto , Estudios Retrospectivos , Factores de Tiempo , Triyodotironina/sangreRESUMEN
BACKGROUND: Evaluation of a thyroid nodule is a common referral seen by surgeons and frequently requires ultrasound-guided fine needle aspiration (US-guided FNA). While surgical residents may have sufficient exposure to thyroid surgery, many lack exposure to office-based procedures, such as US-guided FNA. General surgery residents should be provided with knowledge and practical skills in the application of diagnostic and interventional neck ultrasound to manage the common workup of a thyroid nodule. METHODS: This study sought to instruct and measure surgical residents' performance in thyroid US-guided FNA and evaluate their views regarding instituting such a formal curriculum. Twelve (n = 12) senior residents completed a written pretest and questionnaire, then watched an instructional video and practiced a simulated thyroid US-guided FNA on our created model. Then residents were evaluated while performing actual thyroid US-guided FNAs on patients in our clinic. Residents then completed the same written exam and questionnaire for objective measure. RESULTS: Eight of the chief residents (62%) felt "not comfortable" with the procedure on the pre-course survey; this was reduced to 0% on the post-course survey. Moderate comfort level increased from 15% to 50% and extreme comfort increased from 0% to 8%. From the 11 residents who completed the pre- and post-test exam, 82% (n = 9) significantly improved their score through the curriculum (pre-test: 40.9 vs. post-test: 61.8; p = 0.05). CONCLUSION: With focused instruction, residents are able to learn ultrasound-guided thyroid biopsy with improvement in subjective confidence level and objective measures. Resident feedback was positive and emphasized the importance of such training in surgical residency curriculum.
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Competencia Clínica , Educación de Postgrado en Medicina/métodos , Cirugía General/educación , Biopsia Guiada por Imagen , Nódulo Tiroideo/diagnóstico por imagen , Ultrasonografía Intervencional , Biopsia con Aguja Fina , Curriculum , Humanos , Internado y Residencia/métodos , Entrenamiento Simulado , Nódulo Tiroideo/patología , Estados UnidosAsunto(s)
Nódulo Tiroideo/patología , Adulto , Anciano , Biopsia con Aguja Fina , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Neoplasias de la Tiroides/patología , Nódulo Tiroideo/clasificación , Nódulo Tiroideo/genética , Nódulo Tiroideo/cirugía , TiroidectomíaRESUMEN
Within social hierarchies, low social status is associated with increased vigilance, hostile expectations, and reactive aggression. We propose that societal devaluation is common across many low social status groups and produces a sense of threatened social worth. Threatened social worth may lead those of low status to be more vigilant towards social threats, thereby increasing the likelihood of hostile attributions and endorsement of aggression. Integrating theory on belongingness, social rejection, and stigma compensation, two studies test a sequential process model demonstrating that threatened social worth mediates the relationship between status, hostile attributions, and endorsement of aggression. Employing a relative status manipulation, Study 2 reveals a causal effect of status and highlights the importance of perceptions of low social status on threatened social worth. These data demonstrate the role of social worth in explaining the link between status and hostility and have implications for research in the social, health, and developmental domains.
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Agresión/psicología , Hostilidad , Clase Social , Percepción Social , Adulto , Femenino , Jerarquia Social , Humanos , Renta , Masculino , Modelos TeóricosRESUMEN
CONTEXT: Timely processing of blood cultures with positive results, including Gram staining and notification of clinicians, is a critical function of the clinical microbiology laboratory. Analysis of processing time in our laboratory revealed opportunities to enhance workflow efficiency. We found that the average time from positive blood culture result to removal of the bottle for processing (positive-to-removal [PR] time) was inadequate for our rapid pathogen identification program. OBJECTIVE: To determine whether increased vigilance about PR time and prioritization of laboratory resources would decrease PR time and total processing time. DESIGN: We performed a retrospective analysis of blood culture PR time 7 months before and 7 months after an in-service meeting during which the importance of PR time was emphasized, and corrective measures were implemented. RESULTS: Before the in-service meeting, the average PR time for 5057 samples was 38 minutes, with an aggregate time of 192,251 minutes. Unexpectedly, we discovered that only 51.8% (2617 of 5057) of the positive blood cultures were removed in less than 10 minutes. After the in-service meeting, for 5293 samples, the average PR time improved to 8 minutes, the aggregate time improved to 44,630 minutes, and 84.5% (4470 of 5293) of the positive blood cultures were removed in less than 10 minutes. These improvements reduced the time to telephone notification of the Gram stain results to a caregiver by 46.7% (from 105 minutes to 56 minutes). CONCLUSIONS: Increased awareness of barriers to rapid pathogen identification and interventions for improving performance time significantly enhanced care of patients with bloodstream infections.
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Bacteriemia/diagnóstico , Sangre/microbiología , Fungemia/diagnóstico , Técnicas Microbiológicas/normas , Bacteriemia/microbiología , Fungemia/microbiología , Humanos , Laboratorios de Hospital , Técnicas Microbiológicas/instrumentación , Técnicas Microbiológicas/métodos , Estudios Retrospectivos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Factores de TiempoRESUMEN
Lymphadenectomy is the standard of care for metastatic melanoma in the inguinal lymph node basin. Historically, open surgery was the only treatment option. However, in recent years, videoscopic inguinal lymphadenectomy (VIL) has become a popular approach as it offers a minimally invasive alternative, provides similar oncologic control and reduces wound complications. Even though the VIL approach is being used more frequently, the patient populations that stand to benefit the most from this approach are still under investigation. Despite continued advances in safety for laparoscopic surgery, many surgeons are hesitant to perform these procedures on pregnant women. In this report, we present a successful VIL in a pregnant patient, describe our technique and demonstrate the safety of performing VIL in expectant mothers. To our knowledge, this case represents the first VIL performed in an expectant mother.
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BACKGROUND: An intervention for Gram-negative bloodstream infections that integrated mass spectrometry technology for rapid diagnosis with antimicrobial stewardship oversight significantly improved patient outcomes and reduced hospital costs. As antibiotic resistance rates continue to grow at an alarming speed, the current study was undertaken to assess the impact of this intervention in a challenging patient population with bloodstream infections caused by antibiotic-resistant Gram-negative bacteria. METHODS: A total of 153 patients with antibiotic-resistant Gram-negative bacteremia hospitalized prior to the study intervention were compared to 112 patients treated post-implementation. Outcomes assessed included time to optimal antibiotic therapy, time to active treatment when inactive, hospital and intensive care unit length of stay, all-cause 30-day mortality, and total hospital expenditures. RESULTS: Integrating rapid diagnostics with antimicrobial stewardship improved time to optimal antibiotic therapy (80.9 h in the pre-intervention period versus 23.2 h in the intervention period, P < 0.001) and effective antibiotic therapy (89.7 h versus 32 h, P < 0.001). Patients in the pre-intervention period had increased duration of hospitalization compared to those in the intervention period (23.3 days versus 15.3 days, P = 0.0001) and longer intensive care unit length of stay (16 days versus 10.7 days, P = 0.008). Mortality among patients during the intervention period was lower (21% versus 8.9%, P = 0.01) and our study intervention remained a significant predictor of survival (OR, 0.3; 95% confidence interval [CI], 0.12-0.79) after multivariate logistic regression. Mean hospital costs for each inpatient survivor were reduced $26,298 in the intervention cohort resulting in an estimated annual cost savings of $2.4 million (P = 0.002). CONCLUSIONS: Integration of rapid identification and susceptibility techniques with antimicrobial stewardship resulted in significant improvements in clinical and financial outcomes for patients with bloodstream infections caused by antibiotic-resistant Gram-negatives. The intervention decreased hospital and intensive care unit length of stay, total hospital costs, and reduced all-cause 30-day mortality.
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Acinetobacter baumannii/aislamiento & purificación , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Escherichia coli/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Klebsiella/aislamiento & purificación , Pseudomonas aeruginosa/aislamiento & purificación , Infecciones por Acinetobacter/diagnóstico , Infecciones por Acinetobacter/tratamiento farmacológico , Infecciones por Acinetobacter/microbiología , Infecciones por Acinetobacter/mortalidad , Adulto , Anciano , Bacteriemia/diagnóstico , Bacteriemia/microbiología , Bacteriemia/mortalidad , Farmacorresistencia Bacteriana Múltiple , Escherichia coli/enzimología , Infecciones por Escherichia coli/diagnóstico , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/mortalidad , Femenino , Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/mortalidad , Costos de Hospital , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos , Klebsiella/enzimología , Infecciones por Klebsiella/diagnóstico , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/microbiología , Infecciones por Klebsiella/mortalidad , Tiempo de Internación , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Infecciones por Pseudomonas/diagnóstico , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Infecciones por Pseudomonas/mortalidad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Tasa de Supervivencia , Factores de Tiempo , Tiempo de Tratamiento , Resultado del Tratamiento , Resistencia betalactámica , beta-Lactamasas/metabolismoRESUMEN
The tumor suppressor p53 can be sent to the proteasome for degradation by placing its nucleo-cytoplasmic shuttling under ligand control. Endogenous p53 is ubiquitinated by MDM2 in the nucleus, and controlling the access of p53 to the nuclear compartment regulates its ubiquitination and proteasomal degradation. This was accomplished by the use of a protein switch that places nuclear translocation under the control of externally applied dexamethasone. Fluorescence microscopy revealed that sending protein switch p53 (PS-p53) to the nucleus produces a distinct punctate distribution in both the cytoplasm and nucleus. The nuclear role in accessing the proteasome was investigated by inhibiting classical nuclear export with leptomycin B. Trapping PS-p53 in the nucleus only allows this punctate staining in that compartment, suggesting that PS-p53 must translocate first to the nuclear compartment for cytoplasmic punctate staining to occur. The role of MDM2 binding was explored by inhibiting MDM2/p53 binding with nutlin-3. Inhibition of this interaction blocked both nuclear export and cytoplasmic and nuclear punctate staining, providing evidence that any change in localization after nuclear translocation is due to MDM2 binding. Further, blocking the proteolytic activity of the proteasome maintained the nuclear localization of the construct. Truncations of p53 were made to determine smaller constructs still capable of interacting with MDM2, and their subcellular localization and degradation potential was observed. PS-p53 and a smaller construct containing the two MDM2 binding regions of p53 (Box I + V) were indeed degraded by the proteasome as measured by loss of enhanced green fluorescent protein that was also fused to the construct. The influence of these constructs on p53 gene transactivation function was assessed and revealed that PS-p53 decreased gene transactivation, while PS-p53(Box I + V) did not significantly change baseline gene transactivation.
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Núcleo Celular/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Transporte Activo de Núcleo Celular , Antineoplásicos/farmacología , Química Farmacéutica , Citoplasma/metabolismo , Evaluación Preclínica de Medicamentos , Ácidos Grasos Insaturados/metabolismo , Genes Reporteros , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Imidazoles/metabolismo , Ligandos , Células MCF-7 , Microscopía Fluorescente , Mutación , Piperazinas/metabolismo , Unión Proteica , Ubiquitina/metabolismoRESUMEN
CONTEXT: Early diagnosis of gram-negative bloodstream infections, prompt identification of the infecting organism, and appropriate antibiotic therapy improve patient care outcomes and decrease health care expenditures. In an era of increasing antimicrobial resistance, methods to acquire and rapidly translate critical results into timely therapies for gram-negative bloodstream infections are needed. OBJECTIVE: To determine whether mass spectrometry technology coupled with antimicrobial stewardship provides a substantially improved alternative to conventional laboratory methods. DESIGN: An evidence-based intervention that integrated matrix-assisted laser desorption and ionization time-of-flight mass spectrometry, rapid antimicrobial susceptibility testing, and near-real-time antimicrobial stewardship practices was implemented. Outcomes in patients hospitalized prior to initiation of the study intervention were compared to those in patients treated after implementation. Differences in length of hospitalization and hospital costs were assessed in survivors. RESULTS: The mean hospital length of stay in the preintervention group survivors (n = 100) was 11.9 versus 9.3 days in the intervention group (n = 101; P = .01). After multivariate analysis, factors independently associated with decreased length of hospitalization included the intervention (hazard ratio, 1.38; 95% confidence interval, 1.01-1.88) and active therapy at 48 hours (hazard ratio, 2.9; confidence interval, 1.15-7.33). Mean hospital costs per patient were $45 709 in the preintervention group and $26 162 in the intervention group (P = .009). CONCLUSIONS: Integration of rapid identification and susceptibility techniques with antimicrobial stewardship significantly improved time to optimal therapy, and it decreased hospital length of stay and total costs. This innovative strategy has ramifications for other areas of patient care.