Optimal control analysis and Practical NMPC applied to refrigeration systems.

This work is focused on optimal control of mechanical compression refrigeration systems. A reduced-order state-space model based on the moving boundary approach is proposed for the canonical cycle, which eases the controller design. The optimal cycle (that satisfying the cooling demand while maximizing efficiency) is defined by three variables, but only two inputs are available, therefore the controllability of the proposed model is studied. It is shown through optimization simulations how optimal cycles for a range of the cooling demand turn out not to be achieved by keeping the degree of superheating to a minimum. The Practical NMPC and a well-known feedback-plus-feedforward strategy from the literature are compared in simulation, both showing trouble in reaching the optimal cycle, which agrees with the controllability study.

Efecto analgésico del Lupinus mutabilis S (chocho) comparado con morfina / Analgesic effect of Lupinus mutabilis S (chocho) compared to morphine

El Lupinus mutabilis Sweet es una planta con alto contenido calórico y marcados efectos farmacológicos, por lo que pertenece al grupo de plantas nutracéuticas. Objetivo: Comparar la acción analgésica del Lupinus mutabilis S, con el de la Morfina, utilizando la técnica estandarizada de CYTED, del Plantar-test. Materiales y métodos: Utilizamos 50 ratones albinos, machos, de la cepa Holtzman, de aproximadamente 25 gramos de peso, obtenidos del bioterio del MINSA-Chorrillos, a los que previamente se les acondicionó en el bioterio de la Facultad de Medicina Humana de la Universidad San Martín de Porres y suministró alimento y agua. Se les distribuyó en cinco grupos, G1: Control negativo; G2: Lupinus mutabilis, 300 mg/kg; G3: Lupinus mutabilis, 300 mg/kg + Naloxona, 5 mg/kg; G4: Morfina, 10 mg/kg; y, G5: Morfina, 10 mg/kg + Naloxona, 5 mg/kg. Se determinó el umbral doloroso basal de cada uno de los animales en los diferentes grupos utilizando el test del Hot Plate, el mismo que se repitió a los 30, 60 y 90 ,imutos posteriores a la administración, vía intraperitoneal, de las sustancias correspondientes a cada grupo. Los resultados obtenidos fueron analizados estadisticamente con el programa Graph Pad Prism y Excel XP. Resultados: Apreciamos un efecto analgésico del Lupinus similar al de la Morfina, el mismo que fue bloqueado por Naloxona tanto en el grupo tratado con Morfina como en el tratado con Lupinus mutabilis, a la 1/2 hora. Conclusiones: El Lupinus mutabilis S, mostró un buen efecto analgésico, que al igual que la Morfina fue bloqueado por Naloxona.

Lupinus mutabilis Sweet is a plant with high calorie content and many pharmacological effects; therefore, we consider it as a nutraceutic plant. Objective: The present investigation was made with the purpose of comparing the analgesic properties of Lupinus mutabilis S with Morphine, using the standardized technique of CYTED from Plantar Test. Materials and Method: We used fifty albino mice; male of Holtzman bred weighing 25 grams approximately and got from biotherius at MINSA, Chorrillos, to whom previous conditioning in the biotherius from Facultad de Medicina Humana at Universidad de San Martin de Porres and supply of food and water, distributed in the following five groups, G1: Negative control groups, G2: Lupinus mutabilis 300 mg/kg; G3: Lupinus mutabilis, 300 mg/kg+Naloxoma, 5 mg/kg; G4: Morphine, 10 mg/kg and G5: Morphine. 10 mg/kg+Naloxona, 5 mg/kg. It was determined the basal painful threshold to each one of the animals in different groups, using the test of the Hot Plate, the same thing was repeated at 30, 60 and 90 minutus after administration by intraperitoneal via of substances according to each group. The results were analyzed statistically with the program GraphPad Prism and Excel XP. Results: We appreciate an analgesic effect of Lupinus mutabilis Sweet similar to morphine, the same that was blocked by Naloxone in both group treated with Morphine and Lupinus mutabilis at the first 30 minutes. Conclusions: Lupinus mutabilis Sweet showed a good pharmacological action, which like to Morphine that was blockaded by Naloxone.

Prospective evaluation of liver fibrosis in chronic viral hepatitis C infection using the Sabadell NIHCED (Non-Invasive Hepatitis-C-Related Cirrhosis Early Detection) index.

INTRODUCTION: liver disease resulting from chronic hepatitis C virus (HCV) infection follows an asymptomatic course towards cirrhosis and its complications in 20-40% of cases. Earlier studies demonstrated that advanced fibrosis is a prognostic factor. The "gold standard" for the evaluation of fibrosis grade is liver biopsy. Our group validated a predictive index - NIHCED - based on demographic, laboratory parameters, and echographic data to determine the presence of cirrhosis. OBJECTIVE: our objective is to evaluate whether the NIHCED score predicts the presence of advanced fibrosis in patients with chronic HCV infection. MATERIAL AND METHODS: this prospective study included patients with chronic HCV infection who underwent liver biopsy and were administered the NIHCED score. Fibrosis grade correlated with the NIHCED score using the ROC curve analysis and Spearman s correlation coefficient. RESULTS: in total 321 patients were included (male/female ratio 1.27) with a mean age of 48 +/- 14 years. Liver biopsy showed that 131 (30.5%) had no fibrosis or had portal expansion while 190 (69.5%) had advanced fibrosis or cirrhosis. At a cut-off point of 6, sensitivity was 72%, specificity was 76.3%, positive predictive value (PPV) was 81%, negative predictive value (NPV) was 63.7%, and diagnostic accuracy was 72.5%, with an area under the curve (AUC) of 0.787, and a Spearman s correlation coefficient of r = 0.65. CONCLUSIONS: the NIHCED score predicts the presence of advanced fibrosis in an elevated percentage of patients with a need of liver biopsy.

Evaluación de la fibrosis hepática en la hepatitis crónica por virus C mediante la aplicación prospectiva del Sabadell’s NIHCED score (Sabadell’s Non Invasive, Hepatitis C Related-Cirrhosis Early Detection Score) / Prospective evaluation of liver fibrosis in chronic viral hepatitis C infection using the Sabadell NIHCED: non-invasive hepatitis C related cirrhosis early detection) index

Introducción: la hepatitis crónica por VHC cursa de forma asintomática desarrollando cirrosis hepática y sus complicaciones en un 20-40% de los casos. En estudios previos se ha demostrado que la fibrosis avanzada es un factor pronóstico fundamental. El método gold standard para la valoración del grado de fibrosis es la biopsia hepática. Nuestro grupo ha validado un índice predictivo, el NIHCED (Sabadell's Non Invasive, Hepatitis C related-Cirrosis Early Detection Score), basado en datos demográficos, analíticos y ecográficos para determinar la presencia de cirrosis. Objetivo: nuestro objetivo es el de evaluar si el NIHCED predice la presencia de fibrosis avanzada en los pacientes con hepatitis crónica por virus C. Material y métodos: estudio prospectivo donde se incluyeron pacientes con hepatitis crónica por VHC. Se les realizó una biopsia hepática y el NIHCED. El grado de fibrosis se correlacionó con el valor del NIHCED mediante curva de ROC y el coeficiente de correlación de Spearman. Resultados: se incluyeron un total de 321 pacientes (ratio hombre/mujer 1,27) con una edad media de 48 ± 14 años. La biopsia hepática mostró que 131 (30,5%) no tenían fibrosis o era expansión portal, mientras que 190 (69,5%) tenían fibrosis avanzada o cirrosis. Para un punto de corte de 6 puntos, la sensibilidad fue del 72%, especificidad del 76,3%, VPP del 81%, VPN del 63,7% y una precisión diagnóstica del 72,5%, con un área bajo la curva fue de 0,787 y un coeficiente de correlación de Spearman de r = 0,65. Conclusiones: el NIHCED predice la presencia de fibrosis avanzada en un elevado porcentaje de pacientes sin necesidad de realizar biopsia hepática(AU)

Introduction: liver disease resulting from chronic hepatitis C virus (HCV) infection follows an asymptomatic course towards cirrhosis and its complications in 20-40% of cases. Earlier studies demonstrated that advanced fibrosis is a prognostic factor. The "gold standard" for the evaluation of fibrosis grade is liver biopsy. Our group validated a predictive index - NIHCED - based on demographic, laboratory parameters, and echoghraphic data to determine the presence of cirrhosis. Objective: our objective is to evaluate whether the NIHCED score predicts the presence of advanced fibrosis in patients with chronic HCV infection. Material and methods: this prospective study included patients with chronic HCV infection who underwent liver biopsy and were administered the NIHCED score. Fibrosis grade correlated with the NIHCED score using the ROC curve analysis and Spearman's correlation coefficient. Results: in total 321 patients were included (male/female ratio 1.27) with a mean age of 48 ± 14 years. Liver biopsy showed that 131 (30.5%) had no fibrosis or had portal expansion while 190 (69.5%) had advanced fibrosis or cirrhosis. At a cut-off point of 6, sensitivity was 72%, specificity was 76.3%, positive predictive value (PPV) was 81%, negative predictive value (NPV) was 63.7%, and diagnostic accuracy was 72.5%, with an area under the curve (AUC) of 0.787, and a Spearman's correlation coefficient of r = 0.65. Conclusions: the NIHCED score predicts the presence of advanced fibrosis in an elevated percentage of patients with a need of liver biopsy(AU)

Killing of Coccidioides immitis by human peripheral blood mononuclear cells.

The ability of human peripheral blood mononuclear cells (MNL) obtained from healthy donors to kill the fungus Coccidioides immitis was examined in vitro with an assay that uses a single fungal particle per well. MNL killed 25.0% +/- 3.5% of a coccidioidal arthroconidial target, compared with the 4.7% +/- 2.9% killed by polymorphonuclear leukocytes obtained from the same donors (P = 0.012). Arthroconidial killing by MNL was not dependent on donor delayed dermal hypersensitivity to spherulin. Killing of another fungal target, Candida glabrata, was not significantly different between MNL and polymorphonuclear leukocytes (P = 0.783). Depletion of monocytes from MNL with Sephadex G-10 resulted in a significant reduction in arthroconidial killing (21.4% +/- 13.6% versus 2.4% +/- 3.4%; P = 0.025), while enrichment of monocytes by Percoll density gradient centrifugation or plastic adherence resulted in significantly increased arthroconidial killing compared with that by MNL (P = 0.005 and 0.001, respectively). Killing of 96-h spherules by MNL was 7.3% +/- 3.1%, significantly less than the 21.4% +/- 2.8% killing of arthroconidia in the same experiments (P = 0.016). Incubation of MNL with human recombinant gamma interferon or tumor necrosis factor alpha did not result in increased MNL killing of coccidioidal arthroconidia under various conditions. These results suggest that MNL have an inherent ability to kill coccidioidal arthroconidia in vitro which is not dependent on prior host exposure to C. immitis. This activity appears to reside in peripheral blood monocytes.

In vitro assessment of cellular immunity in human coccidioidomycosis: relationship between dermal hypersensitivity, lymphocyte transformation, and lymphokine production by peripheral blood mononuclear cells from healthy adults.

Dermal hypersensitivity in coccidioidomycosis was compared with three simultaneous measures of in vitro cellular immunity using 35 healthy donors living in an area endemic for coccidioidomycosis. Twenty donors had greater than 5 mm induration to usual-strength spherulin and were considered skin test-positive. Mononuclear cells from these individuals were more responsive by lymphocyte transformation (12,541 +/- 3746 vs. -112 +/- 260 cpm, P = .007) and produced significantly more interleukin-2 (3481 +/- 1067 vs. -5 +/- 69 cpm, P less than .001) and interferon-gamma (1831 +/- 481 vs. 75 +/- 58 pg/ml, P less than .001) than cells from skin test-negative donors in response to a coccidioidal antigen. However, the correlation between the skin test size and the magnitude of the in vitro response among skin test-positive donors was poor (R2 = 0.08, P = .24). These results indicate that healthy individuals with dermal hypersensitivity to Coccidioides immitis can be distinguished from those without hypersensitivity by their cellular in vitro response to a coccidioidal antigen.

Deferoxamine increases the susceptibility of beta-thalassemic, iron-overloaded mice to infection with Listeria monocytogenes.

The effect of the iron chelator deferoxamine (DFO) on resistance to infection with Listeria monocytogenes in mice with a condition analogous to human beta-thalassemia was studied. Intraperitoneal injection of 10 mg DFO resulted in significantly increased mortality when given one, three and six days before infection with L. monocytogenes (for all three time points, p less than 0.02). There were no significant differences in hematocrit, plasma iron, or splenic iron content between the two groups of mice during these time periods. In addition, splenic counts of L. monocytogenes were not significantly higher in DFO-treated compared to saline-treated mice three days after infection. Moreover, background C57Bl/6J mice were not more susceptible to Listeria infection after receiving DFO than were saline-treated controls. In conclusion, acute administration of DFO increases the susceptibility of beta-thalassemic mice to L. monocytogenes. The effect is not seen in background mice and suggests that DFO increases susceptibility to Listeria infection only in animals with iron overload.

Serum and red cell enzyme variants in an Amerindian tribe: the Sirionos (Eastern Bolivia).

Blood samples from 109 Siriono (Eastern Bolivia) belonging to the Tupi-Guarani group were investigated for enzyme variants in the following systems: glucose-6-phosphate dehydrogenase, phosphogluconate dehydrogenase, adenylate kinase, phospho-glucomutase (locus 1 and 2), acid phosphatases, lactate dehydrogenase, NADH diaphorase, pseudocholinesterase (E1 and E2 locus), and serum alkaline phosphatase. The most relevant observations are: (1) A relative lack of polymorphism, a characteristic feature of the Amerindian populations studied up to now. These data are consistent with the hypothesis of a 'common ancestral background' in Indian populations whatever the degree of sociocultural and linguistic diversity, and the geographical distances. (2) Specific traits due to the frequency of alleles in some systems confer to that tribe a particular position among Amerindians. The effects of genetic drift may be postulated in order to explain the high rate of PGM and 6PGD polymorphism. Furthermore, in that small community, the disappearance of some alleles (pa gene) can plausibly be explained in terms of a balanced influence of mutational and selective pressure.