Shortening time scale to reduce thermal effects in quantum transistors.

In this article, we present a quantum transistor model based on a network of coupled quantum oscillators destined to quantum information processing tasks in linear optics. To this end, we show in an analytical way how a set of N quantum oscillators (data-bus) can be used as an optical quantum switch, in which the energy gap of the data bus oscillators plays the role of an adjustable "potential barrier". This enables us to "block or allow" the quantum information to flow from the source to the drain. In addition, we discuss how this device can be useful for implementing single qubit phase-shift quantum gates with high fidelity, so that it can be used as a useful tool. To conclude, during the study of the performance of our device when considering the interaction of this with a thermal reservoir, we highlight the important role played by the set of oscillators which constitute the data-bus in reducing the unwanted effects of the thermal reservoir. This is achieved by reducing the information exchange time (shortening time scale) between the desired oscillators. In particular, we have identified a non-trivial criterion in which the ideal size of the data-bus can be obtained so that it presents the best possible performance. We believe that our study can be perfectly adapted to a large number of thermal reservoir models.

Pancreatitis inducida por drogas / DRUG-INDUCED ACUTE PANCREATITIS

Introducción. Las Reacciones Adversas Medicamentosas (RAM) son una de las principales causas de hospitalización y mortalidad en el sistema de salud (en países desarrollados y en vías de desarrollo), y la relevancia va creciendo año tras año. El objetivo de este estudio fue determinar la incidencia de pancreatitis aguda inducida por drogas y los grupos de drogas que más frecuentemente se ven involucrados. Material y Métodos: Se realizó un estudio retrospectivo tomando como fuente una base de datos de farmacovigilancia del Hospital General de Agudos ¨Dr. Cosme Argerich¨ con información de los últimos cinco años. Resultados: Se detectaron siete casos de pancreatitis inducida por drogas de los cuales fueron dos por quimioterápicos (lapatinib e imatinib), tres por antirretrovirales, uno por inmunosupresores y uno por antihipertensivos (enalapril). En cinco casos fue necesaria la hospitalización y un evento fue mortal. Conclusión: De acuerdo a la bibliografía internacional, a pesar de que los fármacos son solo responsables del 1-2% de casos de pancreatitis aguda inducida por drogas, es importante destacar que es difícil encontrar la causalidad entre el fármaco y el cuadro del paciente, lo que lleva muchas veces a un subdiagnóstico como una pancreatitis idiopática. En el presente estudio, estos casos deben considerarse por su impacto, no solo a nivel de la salud del paciente

Adverse Drug Reactions (ADR) are nowadays an increasing problem in health systems and represents between the 4th and the 6th cause of death in developing countries. Drug induced pancreatitis in a rare ADR but reports are increasing with antiretroviral drugs and new antiviral and anticancer drugs. The aim of this study was to determine the incidence of drug ­ induced pancreatitis in a tertiary care hospital. We used a pharmacovigilance database applying de Naranjo Score for drug causality in adverse medical events. From a total of 2990 ADR we detected 7 cases of pancreatitis. Antiretroviral and anticancer drugs were the drugs most frequently involved.

Muerte inducida por medicamentos / FATAL ADVERSE DRUG REACTIONS

Introducción. Las Reacciones Adversas Medicamentosas (RAM) son una problemática subvalorada en la actualidad y con el incremento de hospitalizaciones por RAM también se esta percibiendo en el mundo un aumento de la incidencia de eventos fatales de RAM. Esto genera un replanteo sobre el uso racional de medicamentos y los costos que traen aparejados los medicamentos para los sistemas de salud. Material y métodos. Se realizó un estudio retrospectivo sobre una base de farmacovigilancia del Hospital General de Agudos Dr. Cosme Argerich con datos de cinco años. Se utilizó el score de Naranjo (tabla 1) para determinar la causalidad de una droga en un evento médico adverso. Fueron incluidos en el trabajo aquellos que fueron determinados como ¨ciertos¨ o ¨probables¨. Resultados. En el perído que involucra la base de farmacovigilancia se detectaron 18 eventos de muertes inducidas por medicamentos. Quimioterápicos, inmunosupresores, corticoides y AINEs fueron las drogas más frecuentemente involucradas. Hemorragia digestiva alta e infecciones las patologías que llevaron a la muerte más frecuentemente. Conclusión. Los grupos de drogas involucrados coinciden con los de la bibliografía internacional. Es preciso contar con sistemas de farmacovigilancia estables y sostenidos para poder determinar y cuantificar con más precisión esta problemática creciente

Adverse Drug Reactions (ADR) are one of the most common cause of death in developed countries and in developing countries too. New drugs and aging of the population are two of the mail causes of this. Approximately half of ADR are preventable. The aim of this Word was to determine the incidence of ADR ­ related death in a tertiary care hospital from Buenos Aires. A pharmacovigilance database was used and we applied the Naranjo Score to determine drug causality in adverse medical events. From a total of 2990 ADR, we detected 18 drug related ­ death. Anticancer, steroids and NSAIDs were the drugs most frequently involved

Family informed consent to organ donation--who performs better: organ procurement organizations, in-hospital coordinators, or intensive care unit professionals?

Successful organ donation in countries adopting informed consent legislation depends on adequate interviewing of potential donors' families. As the number of both referral and effective donors in Brazil increases, health care managers argue whether educational efforts should be directed toward training in-hospital coordinators (IHC)--based on the "Spanish model"--or on the creation of extra-hospital-based professionals (Organ Procurement Organizations [OPOs], the "American model"). Meanwhile, many potential donor families are still approached by intensive care unit (ICU) professionals not trained in donation interviews. The aim of our study was to compare performances in obtaining informed consent from potential donors' families, according to the type of health care professional conducting the interviews: OPO, IHC, or ICU staff. In this retrospective 2-year study performed in Rio de Janeiro, Brazil, we observed an increase in referrals (285 to 411) and consent rates (48.1% to 55.7%). Each year, OPO professionals conducted most family interviews (58.6% and 60.4%, respectively) and obtained better consent rates (63.5% and 64.5%, respectively), when compared to IHC (41.8% and 53.7%, respectively) or untrained ICU professionals (22.1% and 13.4%, respectively). Our results show that adequate professional training is necessary for obtaining family consent for organ donation. Both established international policies for organ procurement and donation, namely the "Spanish model" with its IHCs or the "American model" of extra-hospital OPOs, may equally achieve this task. However, family interviews performed by untrained ICU professionals result in low donation rates and should be discouraged.

Grand rounds to provide feedback on procurement activities.

INTRODUCTION: The Argentine Society of Transplants has set in motion an activity called Grand Rounds to Provide Feedback on Procurement Activities with the purpose of informing, training, and creating awareness by providing information about the evolution of transplanted patients. OBJECTIVE: To measure, describe and analyze the impact that the transplant results presented at the rounds had on participants. RESULTS: One hundred and fifty-eight surveys were conducted. The respondents' average age was 40.06 years (95% confidence interval [CI 95%] 38.39-41.73) including 52.08% women (CI 95%: 43.92%-60.24%); 77.14% physicians (CI 95%: 84.09%-70.18%); 7.85% nurses (CI 95%: 3.4%-12.31%;) and 4.28% surgical nurses and other professional (CI 95%: 0.93%-7.64). When asked how comforted they felt when they learnt about a transplantation, the score prior to the round was 4 (CI 95%: 3.79-4.20) and after it, 4.8 (CI 95%: 4.69-4.90; P < .05). When asked about the transparency of the donation process, the average score before the round was 4.16 (CI 95%: 3.96-4.36) and after it, 4.76 (CI 95%: 4.67-4.86; P < .05). When asked how proactive they considered themselves before, before the average score was 3.54 (CI 95% 3.30-3.78) and post-round, 4.53 (CI 95%: 4.38-4.67; P < .05). When asked if they thought that this activity might be useful for them to manage future donors, 97.41% (CI 95%: 89%-96.98%) of respondents answered affirmatively. The answers to the question whether they thought this activity might increase donation were affirmative in 92.99% of cases; "Don't know", 6.36%; and negative in less than 1%. When consulted about their feelings, the preferred one was "happiness" for 46.82% of respondents; followed by "satisfaction" for 29.36% and "emotion" for 23.80%. The analysis of the open-ended questions revealed that the rounds were perceived as closure of the procurement-transplantation process. CONCLUSIONS: This widely accepted tool was viewed as a vehicle to interconnect links in the work process from organ procurement to transplantation.

Central Composite experimental design applied to removal of lead and nickel from sand.

The aim of this study was to apply Central Composite experimental design in the removal of lead and nickel ions from sand by electrokinetic remediation. Sand was used for an initial study since it is inert, thus making it possible to analyze the parameters influencing the process. Central Composite Design was used to create an experimental program to provide data to model the effects of various factors on removal efficiency. The variables chosen were ion concentration (C), applied potential (E) and time (t). The mathematical relationship between removal efficiency and three significant independent variables can be approximated by a second-order quadratic model. Response Surface Methodology (RSM) was used to describe the individual and interactive effects of three variables at five levels, combined according to a Central Composite Design. This study has shown that Central Composite Design can be applied to the removal of lead and nickel ions from sand, and it is an economical way of obtaining the maximum amount of information with the fewest experiments.

Analysis of HIV type 1 protease and reverse transcriptase sequences from Venezuela for drug resistance-associated mutations and subtype classification: a UNAIDS study.

We report the first study on prevalence of antiretroviral drug-associated resistance mutations in Venezuela. Protease and reverse transcriptase (RT) coding regions were analyzed in DNA samples obtained from 100 HIV-1-infected individuals. Primary resistance mutations to RT inhibitors were identified in 26% of patients treated with these drugs. Transmission of HIV-1-resistant strains was detected in a drug-naive patient (3%). Primary resistance mutations to protease inhibitors (PIs) were present in 9% of the 44 PI-treated patients and in 1 PI-naive individual. Phylogenetic analysis of these samples has resulted in the most extensive survey, to date, of HIV-1 genetic forms circulating in Venezuela. Ninety-nine samples clustered with subtype B, and 1 individual harbored the first B/F recombinant virus reported in Venezuela, with protease clustering with subtype F and RT with subtype B. In addition, this isolate had a new insertion (Glu-34 duplication) in the protease gene.

Sépsis biliar por colédocolitiasis / Biliary Sépsis by colédocolitiasis

Se reporta el caso de una paciente de sexo femenino de 39 años que presentó colédocolitiasis, complicada con colangitis y posteriormente formación de abscesos piógenos múltiples en el hígado. El ECO demostró colelitiasis, vías biliares dilatadas, abscesos hepáticos múltiples. La TC con contraste reportó hepatomegalia con imagen sugestiva de abscesos múltiples en hígado, dilatación de las vías biliares intra y extrahepáticas y la vesícula biliar con aspecto litiásico en su interior. La paciente fue intervenida quirúrgicamente siendo el resultado final favorable. La mayoría de los cálculos del colédoco han migrado de la vesícula y se relacionan con la colecistitis litiásica. Los cálculos provocan obstrucción biliar...

The complete genomic sequence of an HTLV-II isolate from a Guahibo Indian from Venezuela.

A polyclonal CD3(+), CD8(+) T-cell line, G2, was derived from the peripheral blood of a seropositive, PCR-positive, HTLV-IIB infected Guahibo Indian from Venezuela. The cell line is productively infected with HTLV-IIB. The entire HTLV-II G2 proviral DNA was sequenced via PCR using overlapping HTLV-II primer pairs. Phylogenetic analyses indicate that HTLV-II G2 is the most divergent HTLV-IIB strain identified to date. Characterization of its deduced proteins and its relationship to other members of the PTLV/BLV genus of retroviruses are discussed.

Endemic infection with HTLV-IIB in Venezuelan Indians: molecular characterization.

The peripheral blood of 41 Yaruro and Guahibo Indians from Venezuela was examined for HTLV antibodies and DNA. Twenty-five samples (61%) were found to be infected with HTLV-IIB. The sensitivities of the serologic and DNA polymerase chain reaction (PCR) analyses were 80% and 96%, respectively. Epidemiologic studies supported both sexual and perinatal transmission of the virus. Sequence analyses of the HTLV-IIB strains from these Indians indicate that they are unique relative to HTLV-II detected in other groups of humans. HTLV-IIB-G2 isolated from a Guahibo Indian is the most divergent HTLV-IIB strain relative to the prototype HTLV-II NRA.

Highly endemic human T-lymphotropic virus type II (HTLV-II) infection in a Venezuelan Guahibo Amerindian group.

Sera from 166 Guahibo Indians (55% of the population) living in southwest Venezuela were screened by enzyme-linked immunoassay for antibodies to human T-cell lymphotropic virus (HTLV) I and II. Positive samples were confirmed by immunofluorescence and Western blot. Forty-one Guahibos (24.8%) were found to be seropositive. Polymerase chain reaction (PCR) analysis of proviral DNA in mononuclear cell lysates revealed the virus to be HTLV-II. Prevalence increased with age, and sexual contact with HTLV-II-seropositive partners was identified as a risk factor for infection. PCR amplification of a region of the pol gene, utilizing the primer pair SK110/SK111, with subsequent digestion of the 140-base-pair amplification products with HinfI and MseI restriction enzymes, showed an HTLV-II subtype-b restriction pattern in all cases. These data suggest that the substrain infecting this Guahibo community belongs to the b subtype, the most frequent among Paleo-Amerindian populations.

First description of endemic HTLV-II infection among Venezuelan Amerindians.

We describe for the first time the presence of human T lymphotropic virus type II (HTLV-II) infection in Venezuela, among the Pume Amerindians living in the southern plains of the country. Antibodies to HTLV-II antigens were assessed by enzyme immunoassays (Elisa), Western blot, radioimmuno-precipitation, and immunofluorescence; titration studies against HTLV-I- and HTLV-II-infected cell lines were very useful in the differentiation of HTLV-I and HTLV-II antibodies. The HTLV-II general prevalence was 5%; however, there is a striking difference in prevalence between the truly isolated villages (0%) when compared to those living along the riverside and thus in contact with outsiders (9%). Preliminary evidence suggests sexual contact as the main source of transmission. These findings might suggest that HTLV-II in Venezuela originated through contact with outsiders rather than ancient infection related to the origins of the Pume.

Increased proportion of responders to a murine anti-CD3 monoclonal antibody of the IgG1 class in patients with systemic lupus erythematosus (SLE).

A group of Venezuelan patients with SLE showed an increased proportion of responders to Leu-4, an anti-CD3 MoAb of the IgG1 class, compared with ethnically matched non-SLE patients and healthy controls. The rate of proliferative responses or IL-2 production induced by MoAb Leu-4, and the helper effect of macrophages from Leu-4 responders on T cells from a third-party donor were comparable in patients and controls. No significant differences in the binding of murine IgG1 molecules by macrophages from SLE patients and controls were observed. The proportion of monocytes/macrophages expressing Fc gamma RI was significantly higher in SLE patients. However, the expression of FcRII, the type capable of supporting Leu-4-mediated responses, and of Fc gamma RIII was comparable in monocytes from SLE patients and controls. Our results suggest that Venezuelan patients with SLE may have a genetic predisposition for the expression of the phenotypic variant of Fc gamma RII capable of binding murine IgG1 molecules.

Bone marrow and peripheral blood natural killer cell activity in lymphomas. Its response to IL-2.

Natural killer (NK) cytotoxic activity was simultaneously investigated in bone marrow mononuclear cells (BMMC) and peripheral blood lymphocytes (PBL) from nine Hodgkin's disease (HD) and 15 non-Hodgkin lymphoma (NHL) untreated patients. Twenty-five PBL samples and seven bone marrow specimens from healthy individuals were also included as control group (C). NK cell activity was evaluated in basal condition and post-stimulation with human recombinant IL-2 (rIL-2). Data were expressed in K values (number of BMMC or PBL needed to lyse 50% of the target cells). In basal condition, both HD and NHL patients showed a NK cell activity comparable to the C group, both in BMMC (HD, K = 2.48 +/- 1.3; NHL, K = 3.8 +/- 2.0; C, K = 3.2 +/- 0.7) and PBL (HD, K = 2.0 +/- 1.0; NHL, K = 2.3 +/- 1.0; C, K = 2.2 +/- 0.2). Stimulation with rIL-2 induced a significant and comparable enhancement of the NK activity in PBL from HD, NHL and C while the response to rIL-2 of the BMMC in most of the HD and NHL patients was significantly greater than the C group. Responder cells were characterized by negative selection with specific MoAb plus complement as a CD3-, CD16+, CD56+ cytotoxic cell and further confirmed by flow cytometry. We postulate that IL-2 activation of bone marrow NK cell precursors, in addition to enhancing the activity of circulating NK, may be of value for the therapeutic rationale of IL-2 in patients with lymphoma.

Enhanced CD3-mediated T lymphocyte proliferation in patients with systemic lupus erythematosus.

Nonfractionated peripheral blood lymphocytes from patients with systemic lupus erythematosus (SLE) showed enhanced proliferative responses when stimulated via the CD3 pathway. In contrast, proliferative responses induced by phytohemagglutinin were diminished in SLE patients. Levels of CD3-induced interleukin-2 production and interleukin-2 receptor expression were comparable with normal levels. Highly purified T cells also showed augmented CD3 responses, but only in the presence of phorbol myristate acetate or a combination of phorbol myristate acetate plus calcium ionophore A23187, and not with calcium ionophore alone. The data suggest integrity of the T cell receptor/CD3 pathway for T cell activation in patients with SLE, as examined in cultures stimulated with specific anti-CD3 monoclonal antibodies rather than with multivalent lectins. An increased response via the CD3 complex could contribute to the autoimmune activity in human SLE.

Human IFN-gamma up-regulates IL-2 receptors in mitogen-activated T lymphocytes.

This study examined the role of human recombinant interferon-gamma (rIFN-gamma) in the expression of interleukin-2 receptors (IL-2R) by human T lymphocytes. rIFN-gamma enhanced total numbers of IL-2R in mitogen-activated but not resting T cells. Scatchard plot analysis indicated that rIFN-gamma increased both high- and low-affinity receptors, with a predominant effect on the latter. Phytohaemagglutinin (PHA)-activated T cells treated with IFN-gamma showed higher IL-2 binding and greater IL-2 internalization and degradation than cells treated with PHA alone. There was a corresponding increase of mitogen-driven proliferative responses, indicating an increase of functional receptors in IFN-treated cultures. IFN-gamma may influence T-cell activation and proliferation by enhancing expression of IL-2R and promoting IL-2 uptake by mitogen-activated lymphocytes.

Actividad NK en pacientes con linfoma: capacidad de respuedsta AIL-2 / NK activity in patients with lymphoma capacity response AIL-2

En el presente estudio se evaluó la SP y MO de 21 pacientes, no tratados con diagnóstico de linfoma y provenientes de la Unidad de Linfomas del Hospital Universitario de Caracas. El protocolo de investigación incluyó parámetros clínicos e histológicos. En los grupos estudiados se evaluó el porcentaje de células killer naturales (NK) mediante el uso de anticuerpos monoclonales, así como la actividad NK basal postestimulación in vitro con 500/ml de IL 2. Los resultados muestran que los porcentajes de células en SP y MO son similares en pacientes con EH y LNH en relación al grupo de control

Down-regulation of immunoglobulin and IgM-rheumatoid factor synthesis by oral treatment of rheumatoid arthritis patients with a nonsteroidal antiinflammatory drug.

We examined the effect of treatment with piroxicam, a nonsteroidal antiinflammatory drug (NSAID), on immunoglobulin (Ig) and IgM-rheumatoid factor (IgM-RF) synthesis in vitro by lymphocytes of patients with rheumatoid arthritis (RA). Oral treatment with piroxicam induced a progressive decrease of spontaneous IgM-RF production by unstimulated lymphocyte cultures during 12 weeks of observation. Also, pokeweed mitogen (PWM)-driven Ig synthesis was significantly diminished and the effect on total IgM production was sustained until the end of the study. This modulation of humoral responses is consistent with the drop in RF sera level. In addition, we also showed that treatment with NSAIDs can decrease RF levels in the synovial space. NSAIDs may have a long-term beneficial effect in patients with RA due to their modulatory role of lymphocyte responses.

Helper activity by human large granular lymphocytes in in vitro immunoglobulin synthesis.

In the present study we have examined the effect of human large granular lymphocytes (LGL) from healthy donors on Ig synthesis by autologous B lymphocytes. The results showed that this cell population has a consistent helper activity in pokeweed mitogen-activated cultures even when added at very low numbers. LGL can mediate their effect by secreting soluble helper factors capable of modulating B-cell responses as evidenced by the enhancement of IgG and IgM production by supernatants obtained from LGL cultures. Preincubation with interferon gamma further potentiated the helper activity by LGL.