Dynamic optimisation of unbalanced distribution network management by model predictive control with Markov reward processes.

In this work, a two-level control system is used to minimize the total active power losses of an active distribution system connected to the external grid and composed of a wind turbine, two photovoltaic power sources, and two batteries. At the first control level, a model-based predictive control (MPC) is run, using non-homogeneous Markov reward models for wind power prediction and homogeneous Markov reward models for photovoltaic power. At the second level, an algorithm is run for optimal management of voltage control assets, such as voltage regulating transformers, to minimize losses. Different scenarios have been considered, highlighting the advantages of using an MPC framework. This results in an optimization process that can be influenced by different time horizons depending on whether or not the MPC is applied. The predictions allow considering a long-horizon stepwise optimization process that leads to an increasing number of variables along with the decrease of total active power losses. When the MPC is not applied, a short-horizon analysis is performed with a decrease in both the number of variables and the quality of the results. Different cases are considered in which the nominal power of a photovoltaic unit and the battery capacity are modified.

Improvement in Kidney Function after Discontinuation of Fenofibrate in Outpatient Nephrology Consultation for Chronic Kidney Disease.

BACKGROUND: It has been noted in observational and interventional studies that individuals exposed to fenofibrate can exhibit a rise in serum creatinine (sCr) concentration. However, it is not known to what extent this phenomenon impacts kidney function in patients who are referred to a nephrology clinic for consultation for chronic kidney disease (CKD). METHODS: We conducted a prospective observational study of patients referred to our nephrology clinic for a new evaluation of a rise in sCr or worsening CKD and who were on fenofibrate therapy. We examined the effect of discontinuation of fenofibrate on kidney function, change in sCr, and estimated glomerular filtration (eGFR) at 3, 6, and 12 months. RESULTS: A total of 22 patients (59% women, 86% White, 59% with type 2 diabetes, and 18% with peripheral arterial disease) were captured over 2.5 years. Median sCr at the time of fenofibrate discontinuation was 1.9 (1.1-3.3) mg/dL and eGFR, 32 (17-57) mL/min; proteinuria was absent in 17 (77%). Upon discontinuation of fenofibrate, median sCr decreased to 1.5 (0.9-2.4), 1.4 (1.0-2.5), and 1.4 (1.0-2.3) mg/dL at 3, 6, and 12 months, respectively (p < 0.05); whereas median eGFR increased to 44 (27-71), 45 (23-71), and 42 (21-71) mL/min, respectively (p < 0.05). A ≥30% rise in eGFR was observed in 59% of the patients at 3 months, and it persisted in 45% and 50% of patients at 6 and 12 months, respectively. CONCLUSION: Discontinuation of fenofibrate in patients referred for CKD evaluation can result in sustained reduction in sCr in about half of the patients and for up to 1 year. There is a need to raise awareness among primary practitioners about this phenomenon. Recognition of fenofibrate as a cause of rise in sCr could reduce unnecessary nephrology consultation and resource utilization.

Instantaneous Disturbance Index for Power Distribution Networks.

The stability of power systems is very sensitive to voltage or current variations caused by the discontinuous supply of renewable power feeders. Moreover, the impact of these anomalies varies depending on the sensitivity/resilience of customer and transmission system equipment to those deviations. From any of these points of view, an instantaneous characterization of power quality (PQ) aspects becomes an important task. For this purpose, a wavelet-based power quality indices (PQIs) are introduced in this paper. An instantaneous disturbance index (ITD(t)) and a Global Disturbance Ratio index (GDR) are defined to integrally reflect the PQ level in Power Distribution Networks (PDN) under steady-state and/or transient conditions. With only these two indices it is possible to quantify the effects of non-stationary disturbances with high resolution and precision. These PQIs offer an advantage over other similar because of the suitable choice of mother wavelet function that permits to minimize leakage errors between wavelet levels. The wavelet-based algorithms which give rise to these PQIs can be implemented in smart sensors and used for monitoring purposes in PDN. The applicability of the proposed indices is validated by using a real-time experimental platform. In this emulated power system, signals are generated and real-time data are analyzed by a specifically designed software. The effectiveness of this method of detection and identification of disturbances has been proven by comparing the proposed PQIs with classical indices. The results confirm that the proposed method efficiently extracts the characteristics of each component from the multi-event test signals and thus clearly indicates the combined effect of these events through an accurate estimation of the PQIs.

AKI and Collapsing Glomerulopathy Associated with COVID-19 and APOL 1 High-Risk Genotype.

BACKGROUND: Kidney involvement is a feature of COVID-19 and it can be severe in Black patients. Previous research linked increased susceptibility to collapsing glomerulopathy, including in patients with HIV-associated nephropathy, to apo L1 (APOL1) variants that are more common in those of African descent. METHODS: To investigate genetic, histopathologic, and molecular features in six Black patients with COVID-19 presenting with AKI and de novo nephrotic-range proteinuria, we obtained biopsied kidney tissue, which was examined by in situ hybridization for viral detection and by NanoString for COVID-19 and acute tubular injury-associated genes. We also collected peripheral blood for APOL1 genotyping. RESULTS: This case series included six Black patients with COVID-19 (four men, two women), mean age 55 years. At biopsy day, mean serum creatinine was 6.5 mg/dl and mean urine protein-creatinine ratio was 11.5 g. Kidney biopsy specimens showed collapsing glomerulopathy, extensive foot process effacement, and focal/diffuse acute tubular injury. Three patients had endothelial reticular aggregates. We found no evidence of viral particles or SARS-CoV-2 RNA. NanoString showed elevated chemokine gene expression and changes in expression of genes associated with acute tubular injury compared with controls. All six patients had an APOL1 high-risk genotype. Five patients needed dialysis (two of whom died); one partially recovered without dialysis. CONCLUSIONS: Collapsing glomerulopathy in Black patients with COVID-19 was associated with high-risk APOL1 variants. We found no direct viral infection in the kidneys, suggesting a possible alternative mechanism: a "two-hit" combination of genetic predisposition and cytokine-mediated host response to SARS-CoV-2 infection. Given this entity's resemblance with HIV-associated nephropathy, we propose the term COVID-19-associated nephropathy to describe it.

Acute Kidney Injury Associated with Coronavirus Disease 2019 in Urban New Orleans.

Background: AKI is a manifestation of COVID-19 (CoV-AKI). However, there is paucity of data from the United States, particularly from a predominantly black population. We report the phenotype and outcomes of AKI at an academic hospital in New Orleans. Methods: We conducted an observational study in patients hospitalized at Ochsner Medical Center over a 1-month period with COVID-19 and diagnosis of AKI (KDIGO). We examined the rates of RRT and in-hospital mortality as outcome measures. Results: Among 575 admissions (70% black) with COVID-19 [173 (30%) to an intensive care unit (ICU)], we found 161 (28%) cases of AKI (61% ICU and 14% general ward admissions). Patients were predominantly men (62%) and hypertensive (83%). Median body mass index (BMI) was higher among those with AKI (34 versus 31 kg/m2, P<0.0001). AKI over preexisting CKD occurred in 35%. Median follow-up was 25 (1-45) days. The in-hospital mortality rate for the AKI cohort was 50%. Vasopressors and/or mechanical ventilation were required in 105 (65%) of those with AKI. RRT was required in 89 (55%) patients. Those with AKI requiring RRT (AKI-RRT) had higher median BMI (35 versus 33 kg/m2, P=0.05) and younger age (61 versus 68, P=0.0003). Initial values of ferritin, C-reactive protein, procalcitonin, and lactate dehydrogenase were higher among those with AKI; and among them, values were higher for those with AKI-RRT. Ischemic acute tubular injury (ATI) and rhabdomyolysis accounted for 66% and 7% of causes, respectively. In 13%, no obvious cause of AKI was identified aside from COVID-19 diagnosis. Conclusions: CoV-AKI is associated with high rates of RRT and death. Higher BMI and inflammatory marker levels are associated with AKI as well as with AKI-RRT. Hemodynamic instability leading to ischemic ATI is the predominant cause of AKI in this setting.

Fractional CO2 laser treatment for vulvovaginal atrophy symptoms and vaginal rejuvenation in perimenopausal women.

BACKGROUND: This study investigated a novel fractional carbon dioxide (CO2) laser for treatment of symptoms associated with vulvovaginal atrophy (VVA) in perimenopausal women. METHODS: The study included 21 perimenopausal women (mean age 45±7 years) treated three times by CO2 laser resurfacing and coagulation of the vaginal canal tissue and mucosal tissue of the introitus. Vaginal health index (VHI) scores were computed by the investigator at baseline and follow-ups. Subjects reported on sexual function, satisfaction, and improvement with treatment. A visual analog scale was used to measure discomfort with treatment. RESULTS: Vaginal health and subject assessment of vaginal symptoms improved with successive treatments. At 12 weeks following the third treatment, 82% of the patients showed a statistically significant improvement in VHI (P<0.05). Additionally, 81% of subjects reported improvement in sexual gratification, 94% reported improvement in vaginal rejuvenation, and 100% reported satisfaction with treatment. VHI improvement remained significant at 6-8 months after treatments (P<0.01). Most patients (97%) reported no to mild discomfort with treatment. Responses were mild and transient following treatment, with itching being the most commonly reported (20%) side effect. CONCLUSION: In this study, fractional CO2 laser treatment was associated with improvement of vaginal health and amelioration of symptoms of VVA, resulting in improved sexual function in perimenopausal women. Treatment time was quick, and there was minimal discomfort associated with treatment. Investigation of clinical outcome in a larger study population is warranted.

Anesthetic implications of two genetic translocation (6p21; 6p13) in a patient with history of congenital varicella syndrome: a case report.

The coexistence of multiple chromosomal abnormalities and Congenital Varicella Syndrome (CVS) in one patient is a rare event in which anesthetic implications should be considered. This case report describes a 9-year-old female with CVS and a karyotype analysis of 6p21; 16p13 genetic translocations. We conducted a detailed investigation of the consequences of such findings and the potential outcomes in anesthesia of this uncommon incident including thorough research on the characteristics present in each condition. We concluded that: (1) coexistence of two genetic translocations (6p21; 16p13) in one patient, and simultaneously with CVS is undoubtedly an extremely rare event; (2) difficult airway management, potential cardiac dysfunction, risk of pulmonary aspiration, fluid disturbances, and a hard to access peripheral vascularity are among the most important anesthetic implications as a consequence of having all these disorders; (3) ketamine was a safety and efficacious option for sedation during fiber optic bronchoscopy.

[Laryngeal function as node metastasis predictor in patients with cancer of the larynx]. / Funcionalidad laríngea como predictora de metástasis ganglionares en pacientes con cáncer de laringe.

INTRODUCTION: Although the possibility of developing cervical node metastases (CNM) in patients with squamous cell carcinoma of the larynx (SCCL) depends on the site of tumor origin, other factors may be associated, even in glottic tumors. The objective of this study was to determine factors associated with CNM. METHODS: We carried out a retrospective analysis of a series of patients with SCCL. We analyzed the following variables: T-staging, tumor site, and arytenoid-mobility/fixation. and correlated them with histopathological node status. Statistical significance was assessed using chi2 tests. RESULTS: 91 patients were included 82 were male and 9 female; median age was 66 years. The most frequently affected site was the glottic-subglottic region (38) followed by the glottis (22). The most frequent T stage was T3 (46%) followed by T4 (25%); 81% were NO and 19% N+. 76 (83%) had arytenoid fixation. Factors associated with CNM included glottic-supraglottic infiltration (65%) and arytenoid fixation (17% vs. 0, p = 0.048). None of the patients with arytenoid mobility had CNM. Tumor infiltration to thyroid gland was observed among 14% of patients studied The most important risk factor was subglottic extension (17%; p = 0.5). CONCLUSIONS: Lack of mobility of the arytenoid cartilage is a factor associated with CNM among SCCL patients. A subglottic tumor is a risk factor for thyroid infiltration

Linfoma angiocéntrico cutáneo a células T de la infancia / Angiocentric cutaneous T-cell lymphoma of childhood

El linfoma angiocéntrico a células T de la infancia (ACTCLC) es una rara variante de linfoma cutánea de células T que afecta mayormente a niños. Describimos un niño de 14 años con erupción recurrente de lesiones autorresolutivas, con hallazgos clínicos, evolución e histología similares a los casos publicados previamente por otros autores.

Investigación de un foco de leishmaniasis cutánea en la zona andina del departamento de Nariño / Investigation of a focus of cutaneous leishmaniasis in the zone andina of the Nariño Department

En el municipio de Samaniego, ubicado en la zona andina del departamento de Nariño, se dectectaron 14 casos de leishmaniasis cutánea entre 1992 y 1995, presnetándose 13 de ellos (93 por ciento) en niños menores de 13 años. En todos, las lesiones se localizaron en la cara. En tres de los casos se pudieron tipificar las cepas, correspondiendo a L. mexicana, resultado que coincide con la tipificación del primer paciente encontrado en Samaniego en 1984 y primer caso de leishmaniasis cutánea anérgica difusa informado en Colombia. Paralelamente, se identificaron las especies de flebotomíneos recolectados en la zona, correspondiendo todos a Lutzomya columbiana (grupo verrucarum), hallazgo que concuerda con varios informes anteriores de la misma region desde 1940, cuando se buscaba el vector de la epidemia de bartonelosis en esta zona nariñense, hasta 1984 cuando el INS realizó muestreos a raíz del mencionado caso de leishmaniasis difusa encontrado por nosotros en ese municipio. Aunque no se logró demostrar infección natural en los 400 flebotomíneos capturados, sí se consiguió infectar algunos especímenes de Lutzomya columbiana, expuestos a hámsteres inoculados con la cepa de L. mexicana aislada de un paciente incluído en el estudio. Por este hallazgo y por la evidencia epidemiológica, se incrimina a Lutzomya columbiana como posible trasmisor de L. mexicana, vector que hasta la fecha no había sido involucrado en la trasmisión de leishmania. Todos los pacientes estudiados respondieron al tratamiento convencional con glucantime

Leishmaniasis difusa / Difuse leishmaniasis

Se presentan cuatro pacientes con leishmaniasis difusa, procedentes de cuatro regiones de Colombia, diagnosticados inicialmente mediante el estudio histopatologico. Dos casos tenian lesiones diseminadas, en una nina de 10 anos y en un hombre de 80 anos. Los otros dos casos, hombres de 33 y 62 anos, presentaron lesiones nodulares iniciales que curaron con calor local y glucantime. Todos tuvieron leishmaninas negativas. Se confirma que la entidad puede curar cuando no esta diseminada. El calor local fue muy util en un caso con lesion unica inicial. La inoculacion al hamster con macerados de biopsias de dos de los pacientes les origino prominentes "histiocitomas" en el hocico y las almohadillas plantares. En un caso no diseminado se identifico el parasito como L.m. amazonensis mediante isoenzimas. En el paciente de 80 anos, el agente causal fue una cepa de L mexicana. Ilustramos las lesiones clinicas, enfatizamos el aspecto tipico de la imagen macrofago mediante imagenes de microscopia electronica. Las caracteristicas de la enfermedad y la literatura sobre la misma se revisa ampliamente