A machine learning-based model for 1-year mortality prediction in patients admitted to an Intensive Care Unit with a diagnosis of sepsis.

INTRODUCTION: Sepsis is associated to a high mortality rate, and its severity must be evaluated quickly. The severity of illness scores used are intended to be applicable to all patient populations, and generally evaluate in-hospital mortality. However, patients with sepsis continue to be at risk of death after hospital discharge. OBJECTIVE: To develop a model for predicting 1-year mortality in critical patients diagnosed with sepsis. PATIENTS: The data corresponding to 5650 admissions of patients with sepsis from the Medical Information Mart for Intensive Care (MIMIC-III) database were evaluated, randomly divided as follows: 70% for training and 30% for validation. DESIGN: A retrospective register-based cohort study was carried out. The clinical information of the first 24h after admission was used to develop a 1-year mortality prediction model based on Stochastic Gradient Boosting (SGB) methodology. Variable selection was addressed using Least Absolute Shrinkage and Selection Operator (LASSO) and SGB variable importance methodologies. The predictive power was evaluated using the area under the ROC curve (AUROC). RESULTS: An AUROC of 0.8039 (95% confidence interval (CI): [0.8033 0.8045]) was obtained in the validation subset. The model exceeded the predictive performances obtained with traditional severity of disease scores in the same subset. CONCLUSION: The use of assembly algorithms, such as SGB, for the generation of a customized model for sepsis yields more accurate 1-year mortality prediction than the traditional scoring systems such as SAPS II, SOFA or OASIS.

GROUT-CONCRETE INTERFACE BOND PERFORMANCE: EFFECT OF INTERFACE MOISTURE ON THE TENSILE BOND STRENGTH AND GROUT MICROSTRUCTURE.

Bond between two cementitious materials is crucial in applications such as repairs, overlays, and connections of prefabricated bridge elements (PBEs), to name just a few. It is the latter that has special interest to the authors of this paper. After performing a dimensional stability study on grout-like materials commonly used as connections between PBEs, it was observed that the so-called 'non-shrink' cementitious grouts showed a considerable amount of early-age shrinkage. This might have negative effects on the integrity of the structure, due not only to the grout material's early degradation, but also to a possible loss of bond between the grout and the prefabricated concrete element. Many factors affect the bond strength between two cementitious materials (e.g., grout-concrete), the presence of moisture at the existing concrete substrate surface being one of them. In this regard, pre-moistening the concrete substrate surface prior to the application of the grout material is sometimes recommended for bond enhancement. This topic has been the focus of numerous research studies in the past; however, there is still controversy among practitioners on the real benefits that this practice might provide. This paper evaluates the tensile bond performance of two non-shrink cementitious grouts applied to the exposed aggregate surface of a concrete substrate, and how the supply of moisture at the grout-concrete interface affects the bond strength. "Pull-off" bond results show increased tensile bond strength when the concrete surface is pre-moistened. Reasons to explain the observed increased bond strength are given after a careful microstructural analysis of the grout-concrete interface. Interfaces where sufficient moisture is provided to the concrete substrate such that moisture movement from the grout is prevented show reduced porosity and increased hydration on the grout side of the interface, which is thought to directly contribute to the increased tensile bond strength.

Assessment of the bio-preparedness and of the training of the French hospital laboratories in the event of biological threat.

A national laboratory network 'Biotox-Piratox' was created in 2003 in France with the purpose of detecting, confirming and reporting potential biological and chemical threat agents. This network is divided into three levels: Level 1 is dedicated to the evaluation of risks (biological, chemical, radiological), to sampling and packing. Level 2 consists of university and military hospitals, who deal with biological specimens, and of environmental and veterinary laboratories, who deal with environmental and animal samples. Level 3 comprises national reference laboratories and the Jean Mérieux biosafety level (BSL)-4 laboratory in Lyon. This report presents the results of four bio-preparedness exercises to check critical points in the processing of samples. These exercises took place in 2007, 2009, 2010 and 2011. Each of them consisted of two parts. The first part was the identification of an unknown bacterial strain and its susceptibility to antibiotics used as a default in case of a bioterrorist event. The second part was the detection of Class III microorganisms, mainly by molecular techniques. The main lesson learnt in these exercises was that the key to successful detection of biological agents in case of a biological threat was standardisation and validation of the methods implemented by all the laboratories belonging to the network.

[Gastrocolocutaneous fistula: an uncommon complication of percutaneous endoscopic gastrostomy]. / Fístula gastrocolocutánea: una infrecuente complicación de la gastrostomía endoscópica percutánea.

Endoscopic percutaneous gastrostomy is a safe technique although with potential complications before which the clinician has to be on alert in order to early detect them even after a long period of normal functioning. Most of them represent minor problems. Gastrocolocutaneous fistula is a rare but severe complication favored by some risk factors such as previous post-surgical adherences, deformities of the spine, or excessive gastric inflation at the time of performing the technique. We present the case of a patient with PEG with this complication that occurred after the first tube replacement. Our goal was in two senses: on the one hand, to analyze the preventive aspects and basic guidelines for a safe PEG placement to minimize the risks; on the other hand, to alert on the possible presence of this entity to prevent a progressive nutritional impairment. This complication ought to be included in the differential diagnosis of the diarrhea syndrome in the patient carrying a PEG. The diagnostic techniques of choice are radiologic tests such as CT scan and contrast media administration through the tube. Surgical therapy should be reserved to patients with acute peritonitis in order to perform a new gastrostomy.

An adaptation of Pfam profiles to predict protein sub-cellular localization in Gram positive bacteria.

Predicting the sub-cellular localization of a protein can provide useful information to uncover its molecular functions. In this sense, numerous prediction techniques have been developed, which usually have been focused on global information of the protein or sequence alignments. However, several studies have shown that the functional nature of proteins is ruled by conserved sub-sequence patterns known as domains. In this paper, an alternative methodology (PfamFeat) for gram-positive bacterial sub-cellular localization was developed. PfamFeat is based on information provided by Pfam database, which stores a series of HMM-profiles describing common protein domains. The likelihood of a sequence, to be generated by a given HMM-profile, can be used to characterize sequences in order to use pattern recognition techniques. Success rates obtained with a simple one-nearest neighbor classifier demonstrate that this method is competitive with popular sub-cellular prediction algorithms and it constitutes a promising research trend.

Differential PbP27 expression in the yeast and mycelial forms of the Paracoccidioides brasiliensis species complex.

p27 is an antigenic protein produced by Paracoccidioides brasiliensis, the etiologic agent of paracoccidioidomycosis (PCM). Despite its unknown function, it has been suggested as a putative virulence factor, proposed as a suitable target for the design of diagnostic tools and vaccines, and considered as an enhancer in antifungal treatment of PCM. We evaluated sequence polymorphisms of PbP27 gene sequence among isolates, finding some polymorphisms associated with the isolates' phylogenetic origin. In order to determine if there was a differential expression pattern between morphological states and among isolates, we also evaluated PbP27 expression, at transcriptional and translational levels, in mycelia and yeast cultures in 14 isolates belonging to the P. brasiliensis species complex (S1, PS2, PS3, and "Pb01-like", proposed to be named Paracoccidioides lutzii) by two techniques, real time RT-PCR (RT-qPCR) and protein dot blot. For the latter, four protein extracts from different cell localizations (SDS or ß-mercaptoethanol, cytoplasmic and extracellular proteins) were analyzed for each isolate. p27 was present in the four extracts evaluated, mainly in the SDS extract, corresponding to an extract containing proteins loosely attached to the cell wall. This information correlates with immunohistochemical analysis, where positive staining of the yeasts' cell wall was observed. We found that p27 was present in all isolates, mainly in the yeast form. This pattern was corroborated by RT-qPCR results, with higher expression levels found in the yeast form for most of the isolates. The results provide new insights into the expression patterns of this protein, and further characterize it in view of potential uses as a diagnostic and/or therapeutic tool.

Estimators and confidence intervals for the proportion using binary auxiliary information with applications to pharmaceutical studies.

Estimation of a proportion is commonly used in areas such as medicine, biopharmaceutical experiments, etc. Estimation of a proportion using auxiliary information has not been investigated in the literature. Ratio estimators of the population proportion and two-sided confidence intervals based upon auxiliary information are derived in this paper. Real data extracted from the Spanish National Health Survey are used to demonstrate the application of the proposed methods in the estimation of prevalences. Results derived from simulation studies show that proposed estimators are more efficient than the traditional estimator. Proposed confidence intervals outperform the alternative methods, especially in terms of interval width. A study on patients with hypertension is also considered to calculate various estimators and confidence intervals.

[Spanish version of the CAM-ICU (Confusion Assessment Method for the Intensive Care Unit). Pilot study of validation]. / Versión en español del método para la evaluación de la confusión en cuidados intensivos, estudio piloto de validación.

OBJECTIVE: To validate the Spanish version of the CAM-ICU. DESIGN: Validation study. The inter-rater reliability and validity were evaluated using a blind comparison with the DSM-IVTR criteria (reference standard) in a group of patients hospitalized in an Intensive Care Unit (ICU). SETTING: Medical-surgical ICU. PATIENTS: 129 adults with RASS >-4 score, within the 24-48 h of ICU admission. Independent application of the CAM-ICU by two intensive care specialists and evaluation by a psychiatrist using the DSM-IVTR criteria for delirium. RESULTS: Prevalence of delirium in the sample was 26.4%, this being and 48.3% in the 29 patients who received mechanical ventilation. Inter-rater reliability in the whole sample according to the Kappa index was 0.792 (95% CI 0.662-0.922, p<0.001) and in those who received mechanical ventilation was 0.726 (95% CI 0.487-0.965, p<0.001). The sensitivity, specificity, positive predicted value (PPV), negative predicted value (NPV), positive likelihood ratio (+LR), and negative likelihood ratio (-LR) were 79.4% (95% CI 63.2-89.7%); 97.9% (95% CI 92.6-99.4%); 93.1% (95% CI 78.0-98.1%); 93.0% (95% CI 86.3-96.6%); 37.72 (95% CI 9.47-150.20) and 0.21(95% CI 0.11-0.41), respectively, in the whole sample. In mechanically-ventilated patients, sensitivity, specificity, PPV, NPV, +LR and -LR were 92.9% (95% CI 68.5-98.7%); 86.7% (95% CI 62.1-96.3%); 86.7% (95% CI 62.1-96.3%); 92.9% (95% CI 68.5-98.7%); 6.96(95% CI 1.90-25.51) and 0.08 (95% CI 0.01-0.55), respectively. CONCLUSION: The Spanish version of the CAM-ICU is reliable. Its sensitivity, specificity and predictive values should be considered good.

Versión en español del método para la evaluación de la confusión en cuidados intensivos, estudio piloto de validación / Spanish version of the method for evaluation of confusion in intensive cares, pilot study of validation

Objetivo: Validar la versión en español del CAM-ICU (confusion assessment method for the intensive care unit «método para la evaluación de la confusión en cuidados intensivos»). Diseño: Estudio de validación. Se valoran la concordancia interevaluador y la validez mediante comparación ciega con los criterios del Manual Diagnóstico y Estadístico de los Trastornos Mentales, cuarta edición, texto revisado (DSM-IV TR) (estándar de referencia) en un grupo de pacientes ingresados en una unidad de cuidados intensivos (UCI). Ámbito: UCI médico-quirúrgica. Pacientes: Ciento veintinueve adultos con puntuación >-4 en la Richmond Agitation Sedation Scale y entre las 24-48h de admisión en la UCI. Se tuvo en cuenta la aplicación independiente del CAM-ICU por 2 intensivistas y la valoración por psiquiatría con el uso de los criterios del DSM-IV TR para delírium. Resultados: La prevalencia de delírium en la muestra fue del 26,4% y fue del 48,3% en los 29 pacientes que recibieron ventilación mecánica. La concordancia interevaluador en toda la muestra, según el índice κ fue de 0,792 (intervalo de confianza [IC] del 95%: 0,662-0,922; p<0,001) y en los pacientes con ventilación mecánica fue de 0,726 (IC del 95%: 0,487-0,965; p<0,001). La sensibilidad fue del 79,4% (IC del 95%: 63,2-89,7%); la especificidad, del 97,9% (IC del 95% 92,6-99,4%); el valor predictivo positivo (VP+), del 93,1% (IC del 95%: 78,0-98,1%); el valor predictivo negativo (VP-), del 93,0% (IC del 95%: 86,3-96,6%); el cociente de probabilidades positivo (CP+), de 37,72 (IC del 95%: 9,47-150,20), y el cociente de probabilidades negativo (CP-), de 0,21(IC del 95%: 0,11-0,41) en toda la muestra. En los pacientes con ventilación mecánica, la sensibilidad fue del 92,9% (IC del 95%: 68,5-98,7%); la especificidad, del 86,7% (IC del 95%: 62,1-96,3%); el VP+, del 86,7% (IC del 95%: 62,1-96,3%); el VP-, del 92,9% (IC del 95%: 68,5-98,7%); el CP+, de 6,96 (IC del 95%: 1,90-25,51), y el CP-, de 0,08 (IC del 95%: 0,01-0,55). Conclusión: El CAM-ICU en español es reproducible. Su sensibilidad y especificidad así como sus valores predictivos son buenos (AU)

Objective: To validate the Spanish version of the CAM-ICU. Design: Validation study. The inter-rater reliability and validity were evaluated using a blind comparison with the DSM-IVTR criteria (reference standard) in a group of patients hospitalized in an Intensive Care Unit (ICU). Setting Medical-surgical ICU. Patients 129 adults with RASS >-4 score, within the 24-48h of ICU admission. Independent application of the CAM-ICU by two intensive care specialists and evaluation by a psychiatrist using the DSM-IVTR criteria for delirium. Results: Prevalence of delirium in the sample was 26.4%, this being and 48.3% in the 29 patients who received mechanical ventilation. Inter-rater reliability in the whole sample according to the Kappa index was 0.792 (95% CI 0.662-0.922, p<0.001) and in those who received mechanical ventilation was 0.726 (95% CI 0.487-0.965, p<0.001). The sensitivity, specificity, positive predicted value (PPV), negative predicted value (NPV), positive likelihood ratio (+LR), and negative likelihood ratio (-LR) were 79.4% (95% CI 63.2-89.7%); 97.9% (95% CI 92.6-99.4%); 93.1% (95% CI 78.0-98.1%); 93.0% (95% CI 86.3-96.6%); 37.72 (95% CI 9.47-150.20) and 0.21(95% CI 0.11-0.41), respectively, in the whole sample. In mechanically-ventilated patients, sensitivity, specificity, PPV, NPV, +LR and -LR were 92.9% (95% CI 68.5-98.7%); 86.7% (95% CI 62.1-96.3%); 86.7% (95% CI 62.1-96.3%); 92.9% (95% CI 68.5-98.7%); 6.96(95% CI 1.90-25.51) and 0.08 (95% CI 0.01-0.55), respectively. Conclusion: The Spanish version of the CAM-ICU is reliable. Its sensitivity, specificity and predictive values should be considered good (AU)

Evaluation of six pesticides leaching indexes using field data of herbicide application in Casablanca Valley, Chile.

A field study was performed to evaluate the accuracy of six pesticide screening leaching indexes for herbicide movement. Adsorption, dissipation and soil movement were studied in a vineyard in a sandy loam soil during 2005 season. Simazine, diuron, pendimethalin, oxyfluorfen and flumioxazin were applied to bare soil at rates commonly used, and their soil concentrations throughout soil profile were determined at 0, 10, 20, 40 and 90 days after application (DAA). Herbicides were subjected to two pluviometric regimens, natural field condition and modified conditions (plus natural rainfall 180 mm). Leaching indexes utilized were: Briggs's Rf, Hamaker's Rf, LEACH, LPI, GUS and LIX. Simazine reached 120 cm, diuron 90 cm, flumioxazin 30 cm soil depth respectively. Pendimethalin and oxyfluorfen were retained up to 5 cm. None of the herbicides leaching was affected by rainfall regimen. Only flumioxazin field dissipation was clearly affected by pluviometric condition. The best representation of the herbicide soil depth movement and leaching below 15 cm soil depth were: Hamaker's Rf < Briggs's Rf < GUS < LPI, < LEACH < LIX. Field results showed a good correlation between herbicides K(d) and their soil depth movement and mass leached below 15 cm soil depth.

¿Son válidos los documentos de consentimiento informado que utilizamos en cirugía vascular? / are the informed consent documents we use in vascular surgery valid?

Introducción. La cumplimentación de un documento escrito de consentimiento informado (DCI) antes de realizar intervenciones quirúrgicas o exploraciones invasivas es un requisito ético (código deontológico) y legal (Ley 41/2002 de Autonomía del Paciente). Los DCI deben ser específicos para cada procedimiento y suministrar una información suficiente y comprensible. La información que tiene que contener un DCI está ampliamente consensuada en las fuentes bibliográficas. Las técnicas de análisis de legibilidad validadas para nuestra lengua son un instrumento útil para evaluar qué grado de comprensión del DCI tendrá el ciudadano medio. Objetivo. Valorar si en nuestra especialidad disponemos de DCI adecuados: específicos, comprensibles y con un contenido apropiado. Materiales y métodos. Se recogieron los DCI recomendados por la Sociedad Española de Angiología y Cirugía Vascular y sociedades regionales. Se practicó un análisis de legibilidad mediante tres parámetros validados para ello en castellano: índice de Flesh (IF), de complejidad oracional (ICO) y de legibilidad integrada (LEGIN). Se valoró el contenido según el grado de cumplimiento sobre un total de 15 apartados que deben contener los DCI. Resultados. Se encontraron 16 DCI sobre 10 procedimientos. Ningún DCI cumplía criterios de legibilidad mínima según el IF y seis lo cumplían según el ICO y el LEGIN. Ningún DCI cumplía con todos los requisitos de contenido. Conclusiones. Disponemos de DCI sobre pocos procedimientos. La legibilidad formal de los consentimientos informados analizados es deficiente. Los DCI analizados no cumplen con los requisitos de contenido exigibles a este tipo de documentos. Los DCI analizados no parecen apropiados para dar una correcta información al paciente

Introduction. Patients are required to fill in a written informed consent document (ICD) before undergoing surgical interventions or invasive examinations on both ethical (professional code of conduct) and legal grounds (Autonomía del Paciente Law 41/2002). ICDs must be specific for each procedure and provide an adequate amount of information in an understandable form. There is widespread agreement in the literature about the information that must be included in an ICD. Readability analysis techniques that have been validated for Spanish are a useful instrument for assessing how comprehensible the ICD will be to the average citizen. Aim. To examine whether the ICDs used in our speciality are appropriate, specific and understandable, and contain suitable information. Materials and methods. We collected samples of the ICDs recommended by the SEAVC (Spanish Society of Angiology and Vascular Surgery) and regional societies. A readability analysis was performed using three parameters that have been validated for such studies in Spanish: the Flesh index (FI), sentence complexity index (SCI) and integrated readability level index (LEGIN). The content was evaluated according to the extent to which it complied with a total of 15 points that ICDs have to include. Results. In all, 16 ICDs concerned with 10 procedures were found. None of the ICDs met the minimum readability criteria according to the FI and six of them fulfilled SCI and LEGIN criteria. None of the ICDs met all the content criteria. Conclusions. We only have ICDs for a scant number of procedures. The formal readability of the informed consent documents analysed is poor. The ICDs analysed do not comply with the requirements regarding content that this type of documents ought to satisfy. The ICDs examined in this study do not seem to offer patients the information they should be given in this kind of document

Imagen radiológica de hernia de Bochdalek / Radiograph of a Bochdalek hernia

No disponible

Reparación endovascular de aneurisma aortoilíaco en paciente con trasplante renal / Endovascular repair of an aortoiliac aneurysm in a kidney transplant patient

Introducción. La corrección quirúrgica convencional de la patología aneu rismática aortoilíaca en pacientes con trasplante renal pélvico supone un elevado riesgo de isquemia renal durante el clampaje aórtico. La reparación endovascular minimiza dicho riesgo, y no precisa maniobras adicionales para preservar el flujo renal. Caso clínico. Varón 67 años, ex fumador, hipertenso, dislipémico, hiperuricémico, con insuficiencia cardíaca, cardiopatía isquémica, triple bypass aortocoronario, trasplante renal (aloinjerto en fosa ilíaca izquierda), herniorrafía inguinal bilateral y umbilical con malla, que presenta un aneurisma de aorta infrarrenal (AAA) de 4,5 cm y aneurisma de arteria ilíaca derecha (AAID) de 3,7 cm asintomáticos. Dada la necesidad de intervenir el AAID, junto a la coexistencia del AAA y el trasplante renal, se decide realizar una reparación endovascular. Bajo anestesia general y heparinización sistémica, se coloca endoprótesis Talent ® bifurcada aortoilíaca, se ocluye la arteria hipogástrica derecha, y se mantiene permeable la izquierda y la anastomosis del trasplante renal. En el postoperatorio inmediato no se aprecia empeoramiento de la función renal. Se da de alta al paciente con doble antiagregación (clopidogrel 75 mg y AAS 125 mg) al quinto día postoperatorio. A los 8 meses de seguimiento clínico, analítico y radiológico (tomografía computarizada y radiografía simple), el injerto renal sigue permeable con función renal normal. Conclusión. El principal beneficio de la reparación endovascular aneurismática en trasplantes renales pélvicos reside en la rapidez, ausencia de clampaje y en la facilidad de realización, en comparación con las maniobras de preservación flujorrenal en cirugía convencional. Por este motivo, en caso de anatomías favorables, debe considerarse la reparación endovascular como uno de los tratamientos de elección (AU)

Ergotismo: revisión de la bibliografíay presentación de casos / Ergotism: review of the literature and some case reports

Introducción. Aunque el ergotismo o fuego de san Antonio tiene múltiples presentaciones, la más común en la actualidad es la isquemia periférica secundaria a vasoespasmo, que ocurre entre un 0,001-0,002 por ciento de aquellos pacientes en tratamiento con alcaloides ergóticos. Objetivo. Realizar un estudio retrospectivo de la isquemia ergótica en nuestro medio, y, dado que no existe una pauta de actuación estandarizada a seguir, basándonos en nuestra experiencia personal en el Hospital de la Santa Creu i Sant Pau (HSCSP) y en la diversa bibliografía consultada, plantear una terapéutica basada principalmente en la retirada de ergóticos y en la infusión endovenosa de prostaglandinas, con cretamente alprostadil(PGE1)-a-ciclo-dextrano (Sugiran,), por su gran efecto vasodilatador arterial y su acción antiagregante plaquetaria. Pacientes y métodos. Presentamos la serie de nuestro grupo de trabajo en los últimos cinco años, que incluye cuatro casos de isquemia arterial (dos hombres y dos mujeres) con afectación de las extremidades inferiores en tres casos y las superiores en uno. Todos los casos se trataron con supresión de ergóticos, infusión endovenosa de alprostadil (PGE1)-a-ciclo-dextrano, más fármacos coadyuvantes en algunos casos (heparinas, antiagregantes y hemorreológicos). Resultados. Los pacientes presentaron una franca mejoría tras la retirada de los ergóticos; desapareció la amenaza para la extremidad y el dolor en reposo entre 24 y 72 h tras el inicio de la infusión de prostaglandinas. El cuadro clínico mejoró en pocos días, y se recuperaron los pulsos distales en la totalidad de los casos. Conclusiones. Consideramos el uso de alprostadil(PGE1)-a-ciclo-dextrano como una opción terapéutica válida en el tratamiento de la isquemia de etiología ergótica (AU)

Hipernatremia en cirugía laparoscópica de quiste hidatídico hepático en paciente pediátrico / Hypernatremia in laparoscopic surgery for a hydatid liver cyst in a pediatric patient

No disponible

[Comparative study of three systems for in vitro activity investigation of fluconazole against yeast isolates of clinical interest]. / Estudio comparativo de tres sistemas para la investigación in vitro de la actividad del fluconazol frente a organismos levaduriformes de interés clínico.

BACKGROUND: Study of antifungal sensitivity can help in treatment screening and evaluation of patients suffering from some fungal infections. The purpose of this study is to compare fluconazole MICs obtained by E-test and agar dilution with the NCCLS method. MATERIAL AND METHODS: The in vitro activity of fluconazole against 158 yeast strains by three systems: E-test, agar dilution and the microbroth NCCLS M27P method. RESULTS AND CONCLUSION: A correlation between 84 to 100% was observed the degree varying in the result among different species. The E-test was found to be comparable to the NCCLS M27P microbroth method, was easier to perform and provides MIC result for Candida species within 24 h.

Effect of human immunodeficiency virus type 1 on intracellular activation and superoxide production by neutrophils.

The immunopathogenesis of AIDS is associated with the development of opportunistic infections by intracellular pathogens that can invade and reproduce freely because of impaired cellular functions. Neutrophils from asymptomatic human immunodeficiency virus (HIV) type 1-infected persons and from symptomatic patients with AIDS were found to retain normal phagocytosis activity while producing significantly less superoxide than neutrophils from HIV-1-negative subjects, when stimulated through Fc receptors or protein kinase C. After priming with a synthetic HIV-1 envelope peptide and stimulation via the Fc receptor, the neutrophils from HIV-1-negative controls had suppressed superoxide production, reduced phosphorylation of two unidentified cellular proteins, and increased expression of a third phosphoprotein. These results suggest that HIV-1 can produce direct functional damage of neutrophils through binding of envelope components to the cell membrane.