Comparison of Complications in Patients with Ductal Cholangiocarcinoma (CCC) and Patients with Colorectal Liver Metastases (CRLMs) After Portal Vein Embolization (PVE): A Matched Cohort Study.

PURPOSE: To compare complications in patients with cholangiocarcinoma (CCC) and patients with colorectal liver metastases (CRLMs) after portal vein embolization (PVE) and to identify possible predictive factors. MATERIAL AND METHODS: Retrospective analysis of consecutive patients, who underwent PVE between July 2011 and March 2020. The study groups were matched for sex and age. Multivariable analysis was performed for the endpoints of complications categorized according for their respective effect on surgical treatment: "Minor" complications had no effect on subsequent surgical treatment, while "intermediate" and "severe" complications delayed or prevented surgery. RESULTS: A total of 160 patients with either CCC (n = 80) or CRLMs (n = 80) were included: 34/160 experienced complications: 27 (CCC: 21; CRLMs: 6) "minor", 4 (CCC: 3; CRLMs: 1) "intermediate", and 3 (CCC: 2; CRLMs: 1) "severe" complications respectively (p = .01). Patients with CCC received a biliary drainage 5 days on average before PVE. Baseline bilirubin levels were 1.1 mg/dl in CCC patients and 0.55 mg/dl in CRLMs patients (p < .01). Postinterventional infections were more common in CCC patients. The preintervention future liver remnant volume (odds ratio (OR) 0.93; 95% confidence interval (CI) 0.88-0.99; p = .02), body mass index (OR 1.19; 95% CI 1.04-1.36; p = .01), age (OR 0,91; 95% CI 0.84-0.99; p = .01), chemotherapy before PVE (OR 0.03; 95% CI 0.01-0.23; p < .01) and severe liver steatosis (OR 29.52; 95% CI 1.87-467,13; p = .02) were the only significant predictive factors for the occurrence of (minor) complications. CONCLUSION: PVE can be performed in CCC patients with prior biliary drainage, with similar procedural safety as in patients with CRLMs.

Stent Graft Placement by Pseudoaneurysm of the Hepatic Arteries: Efficacy and Patency Rate in Follow-up.

PURPOSE: To investigate efficacy and patency status of stent graft implantation in the treatment of hepatic artery pseudoaneurysm. MATERIALS AND METHODS: A retrospective analysis of patients who had undergone endovascular treatment of hepatic artery pseudoaneurysms between 2011 and 2020 was performed. Medical records were examined to obtain patients' surgical histories and to screen for active bleeding. Angiographic data on vascular access, target vessel, material used and technical success, defined as the exclusion of the pseudoaneurysm by means of a stent graft with sufficient control of bleeding, were collected. Vessel patency at follow-up CT was analyzed and classified as short-term (< 6 weeks), mid-term (between 6 weeks and 1 year), and long-term patency (> 1 year). In case of stent occlusion, collateralization and signs of hepatic hypoperfusion were examined. RESULTS: In total, 30 patients were included and of these, 25 and 5 had undergone stent graft implantation and coiling, respectively. In patients with implanted stent grafts, technical success was achieved in 23/25 patients (92%). Follow-up CT scans were available in 16 patients, showing stent graft patency in 9/16 patients (56%). Short-term, mid-term, and long-term short-term stent patency was found in 81% (13/16), 40% (4/10), and 50% (2/4). In patients with stent graft occlusion, 86% (6/7) exhibited maintenance of arterial liver perfusion via collaterals and 14% (1/7) exhibited liver abscess during follow-up. CONCLUSION: Stent graft provides an effective treatment for hepatic artery pseudoaneurysms. Even though patency rates decreased as a function of time, stent occlusion was mainly asymptomatic due to sufficient collateralization.

Dynamic evaluation of neutrophil-to-lymphocyte ratio as prognostic factor in stage III non-small cell lung cancer treated with chemoradiotherapy.

PURPOSE: Locally advanced non-small cell lung cancer (LA-NSCLC) is frequently treated with chemoradiotherapy (CRT). Despite the efforts, long-term outcomes are poor, and novel therapies have been introduced to improve results. Biomarkers are needed to detect early treatment failure and plan future follow-up and therapies. Our aim is to evaluate the role of dynamics of neutrophil-to-lymphocyte ratio (NLR) in patients with locally advanced NSCLC treated with CRT. METHODS: We retrospectively reviewed patients diagnosed with LA-NSCLC receiving definitive CRT at our center from 2010 to 2015. Baseline and post-treatment NLR were collected from our center database. NLR was dichotomized (threshold = 4) and patients were divided into two groups based on the variation from baseline to post-treatment NLR. The prognostic role and association with response were examined with logistic regression and multivariate Cox regression model, respectively. RESULTS: Ninety-two patients were included. Our analysis shows that NLR after treatment is associated with response to treatment [OR in the multivariate analysis 4.94 (1.01-24.48); p value = 0.048]. Furthermore, NLR and ECOG are independent prognostic factors for progression-free survival (PFS) and overall survival (OS). Specifically, PFS was 25.79 months for the good prognosis group and 12.09 for the poor prognosis group [HR 2.98 (CI 95% = 1.74-5.10), p < 0.001]; and OS was 42.94 months and 18.86 months, respectively [HR 2.81 (CI 95% = 1.62-4.90), p < 0.001]. CONCLUSION: Dynamics of NLR have a prognostic value in stage III NSCLC treated with definitive CRT. Pre- and post-CRT NLR should be evaluated in prospective clinical trials involving consolidation treatment with immunotherapy.

ERCC1, XPF and XPA-locoregional differences and prognostic value of DNA repair protein expression in patients with head and neck squamous cell carcinoma.

OBJECTIVES: Nucleotide excision repair protein expression has been claimed to be responsible for platinum-based chemotherapy resistance. ERCC1, XPF and XPA, core proteins in DNA repair, were evaluated regarding their prognostic value in patients with head and neck squamous cell carcinoma by looking at overall survival and time to recurrence. MATERIALS AND METHODS: Tissue microarrays were constructed from 453 cases of HNSCC, including 222 oral (49%), 126 oropharyngeal (27.8%) and 105 laryngeal (23.2%) tumours. There were 284 XPF, 293 XPA and 294 ERCC1 specimens evaluable for protein expression analysis after immunohistochemical workup. Expression levels were dichotomised into high- and low-expressing groups. Outcomes for overall survival (OS) and time to recurrence (TTR) were analysed using the Kaplan-Meier method. RESULTS: No correlation between ERCC1, XPA and XPF expression and OS was found by looking at the overall patient cohort. However, subsite analysis revealed that high ERCC1 expression was associated with a significantly inferior OS in patients with SCC of the oral cavity (p = 0.028) and showed an independent predictive value in multivariate analysis (p = 0.0123). High XPA expression showed a significantly increased OS in patients with oropharyngeal SCC (p = 0.0386). Regarding XPF, no impact on OS in any subsite could be shown. CONCLUSIONS: While high ERCC1 expression functions as a predictive marker with decreased OS in patients with squamous cell carcinoma of the oral cavity, high XPA expression shows an inverse effect in the subsite of the oropharynx, which has not been described previously. CLINICAL RELEVANCE: ERCC1 and XPA might be candidates to overcome chemotherapy resistance in subtypes of HNSCC.

Molecular subtypes in early colorectal cancer associated with clinical features and patient prognosis.

PURPOSE: After surgical resection, an ample prognosis variability among stages is observed. Multiple prognostic factors are individually studied and some CRC classifiers have been proposed. Not one have been implemented into clinical practice. METHODS/PATIENTS: We classified 105 patients with resected CRC (stage I-III) into five molecular subtypes using BRAFV600E and RAS (KRAS; NRAS) status, and the expression of DNA mismatch repair (MMR) proteins (MLH1 and MSH2). Clinicopathological features and DFS) of distincts groups were evaluated. RESULTS AND CONCLUSIONS: RAS and BRAFV600E mutations were detected in 43.8 and 11.4% of patients, respectively. 19% of tumours had lack of expression of any MMR proteins reflecting a system deficiency (dMMR). Patients with any RAS mutation had lower DFS that patients with RAS wild type (wt) (40.23 vs 45.26 months; p value = 0.035). Of a total of five molecular subtypes, three were MMR proficient (pMMR): RAS mutated (39%), BRAFV600E mutated (6.7%) and RAS/BRAFV600E wt (35.2%); and two were dMMR: BRAFV600E mutated (4.8%) and BRAFV600E wt (14.3%). Left side tumours were more frequently observed in pMMR/RAS and BRAFV600E wt subtype, and right side tumours in dMMR subtypes. Among the three pMMR subtypes, a benefit survival was observed for patients without any mutation in BRAFv600E or RAS oncogenes (median of DFS = 45.5 vs 40.98 months in RAS mutated group; p = 0.084 and vs 34.13 in BRAFv600E mutated group; p = 0.031). Molecular classification using these biomarkers can be useful to identify groups with differences in prognosis.

Polyamines in human breast milk for preterm and term infants.

Maternal milk is the first source of exogenous polyamines for the newborn. Polyamines modulate gut maturation in neonates, but no studies are available on polyamine concentration in human milk of preterm babies, even though they could be important for their immature gut. The present study aimed to determine polyamine concentration in human breast milk of mothers with preterm or term infants during the first month of lactation. Human milk samples were obtained during the first month of lactation from twenty-seven mothers with preterm babies and twelve mothers with babies born at term. The polyamine concentration in human milk was quantified by HPLC. During the first month of lactation, the total polyamine concentration was significantly higher in preterm milk than in term milk samples (7590 (SD 4990) v. 4660 (SD 4830) nmol/l, respectively (P » 0·034)), as well as individual polyamine concentrations. Polyamine concentration in mature milk for preterm babies was significantly higher than that in mature milk for babies at term, and a similar trend was observed in colostrum and transition human milk. The spermidine/spermine ratio was higher in transition milk in preterm v. term samples, while in mature milk, the ratio was significantly lower in preterm than in term babies. In conclusion, the polyamine concentration was significantly higher in human milk for preterm than for term infants. This and the different spermidine/spermine ratios could influence the gut development of premature babies.

[Changes in nutritional state, metabolic control and treatment of type 1 diabetes in the last 20 years]. / Diferencias de estado nutricional, control metabólico y tratamiento de la diabetes tipo 1 en dos décadas.

OBJECTIVE: The aim of this study is to describe changes in anthropometric characteristics, metabolic control, treatment and prevalence of overweight in diabetic children (DM1) from 2007 compared with another similar group from 1986. PATIENTS AND METHODS: Observational retrospective study of two groups of diabetic children (n=90). The collection of variables has been made at two cross-sections, 1986 and 2007. The studied variables were: age, years of DM1, sex, weight, height, BMI (and their Z values), HbA(1c) and treatment with insulin (type, number of doses, IU/day and IU/kg/day). RESULTS: In 2007 group there is a significant increase in Z-weight and Z-BMI (P=.001) when compared with the 1986 group. There was a negative relationship between the years with DM1 and Z-height (P=.05) in the 1986 group. The value of HbA(1c) was lower in the 2007 group (P=.001), but the dose of insulin (IU/day and IU/kg/day) was similar in both groups. The number of daily doses of insulin was higher in the 2007 group (P<.001), the use of insulin analogues dominated overall. A statistically significant relationship between HbA(1c) and treatment with insulin (dose injections, insulin type) was not found. The prevalence of overweight (14.6% vs 2.4%) was significantly higher in the 2007 Group (P=.001). CONCLUSIONS: The metabolic control (HbA(1c)) had improved and the use of multiple daily doses of insulin has been become the standard, but the prevalence of overweight has increased. We must monitor the emergence of insulin resistance and cardiovascular risk factors in this sensitive population to prevent early cardiovascular disease.

Predicting the duration of chemotherapy-induced neutropenia: new scores and validation.

BACKGROUND: the objective of this study was to develop predictive models to classify febrile neutropenic patients into two groups, according to a prediction of the duration of the chemotherapy-induced neutropenia episode. PATIENTS AND METHODS: for this retrospective analysis, 106 patients with solid tumours and an episode of febrile neutropenia (FN) were eligible. A score was attributed to each chemotherapy treatment drug according to its expected toxicity. Three new scores were proposed based only on this classification. Two of them are a combination of the individual drug scores and the third one was built using statistical techniques such as cluster analysis and classification trees. RESULTS: statistical techniques produced the best score, distinguishing two groups of patients with statistically different neutropenia durations, with median durations until haematological recovery of absolute neutrophil count 2 × 10(9)/l of 4 versus 2 days (P < 0.001). CONCLUSIONS: our methodological approach based on statistical techniques identifies the patients who will need the longest times to recover from FN. The input of this predictive system is only the aggressiveness of the cytotoxic agents in a chemotherapy regimen. Our proposal succeeded in distinguishing two groups of patients and the results show better performance than other scores in previous studies.

Validity, reliability, and responsiveness of a new short Visual Simplified Respiratory Questionnaire (VSRQ) for health-related quality of life assessment in chronic obstructive pulmonary disease.

The Visual Simplified Respiratory Questionnaire (VSRQ) was designed to assess health-related quality of life (HRQoL) in patients with chronic obstructive pulmonary disease (COPD). It contains eight items: dyspnea, anxiety, depressed mood, sleep, energy, daily activities, social activities and sexual life. Psychometric properties were assessed during a clinical trial that evaluated the impact of tiotropium on HRQoL of COPD patients. These included the determination of structure, internal consistency reliability, concurrent validity with the St George's Respiratory Questionnaire (SGRQ), test - retest reliability, clinical validity and responsiveness to change over two weeks. Minimal important difference (MID) was calculated; cumulative response curves (CRC) were based on the dyspnea item. Psychometric analyses showed that VSRQ structure was unidimensional. The questionnaire demonstrated good internal consistency reliability (Cronbach's alpha = 0.84), good concurrent validity with SGRQ (Spearman = -0.70) and clinical validity, good test-retest reproducibility (ICC = 0.77), and satisfactory responsiveness (standardized response mean = 0.57; Guyatt's statistic = 0.63). MID was 3.4; CRC median value of the 'minimally improved' patients was 3.5. In conclusion, VSRQ brevity and satisfactory psychometric properties make it a good candidate for large studies to assess HRQoL in COPD patients. Further validation is needed to extend its use in clinical practice.

[Retinopathy of prematurity in the Murcia region of Spain. Incidence and severity]. / Retinopatía del prematuro en la región de Murcia (España). Incidencia y gravedad.

OBJECTIVE: To determine the incidence and severity of Retinopathy of Prematurity (ROP) in the Murcia region of Spain. METHODS: This was a retrospective study of all infants born preterm in the Murcia region during 2004, who were screened for ROP. Our screening criteria were: Infants with a gestational age

Funciona el tejido adiposo marrón como un depósito de acidos grasos poliinsaturados de cadena larga durante el desarrollo postnatal del cerebro? / [Is brown adipose tissue a store of long chain polyunsaturated fatty acids during postnatal developing brain?]

Mammals along their early postnatal period develop a substantial amount of a very active brown adipose tissue (BAT). Through this work we explored the possibility that BAT may function as a long chain polyunsaturated fatty acids reservoir (LC-PUFA) during the rapid growth of brain structures. In new born rats 1, 6, 12 and 20 days old, we analyzed fatty acid percentage of triglycerides (TG) and phospholipid fractions, and the absolute amount of TG. In 6 day old rats we also evaluated the extend of further desaturation of 1-14C linoleic acid administered by intraperitoneal injection. Results demonstrated a drastic increase of TG concentration during experimental period (1,5; 40; 118; 120 mg/g wet weight) and LC-PUFA percentage was higher in [quot ]1 and 6[quot ] than [quot ]12 and 20[quot ] days old rats (16-17% vs 5%). Our results showed that BAT stored important amounts of LC-PUFA. On the other hand, 1-14C linoleic acid incorporation was higher in liver than BAT. In contrast, the desaturated products of 1-14C linoleic acid /1-14C linoleic acid ratio was greater in BAT than liver (>4). This could indicate that BAT synthesizes LC-PUFA in addition to store it. In summary we demonstrated than BAT is an important reservoir of LC-PUFA during postnatal brain growth.

Los mamíferos como el hombre y la rata, poseen durante su desarrollo postnatal temprano un tejido adiposo marrón (TAM) muy activo. En este trabajo se exploró la posibilidad de que el TAM funcione como un depósito de ácidos grasos poliinsaturados de cadena larga (AGPI-CL), durante el período de máximo crecimiento postnatal del cerebro de rata. En el TAM de ratas de 1, 6, 12 y 20 días de edad analizamos la concentración de triglicéridos (TG) y la composición de ácidos grasos en los TG y fosfolípidos (FL). Además, en ratas de 6 días de edad evaluamos la capacidad del TAM para desaturar 1- 14C ácido linoleico administrado por vía intraperitoneal. Los resultados mostraron un rápido incremento en la concentración de TG durante el período experimental (1,5; 40; 118; 120 mg /g de peso húmedo). El porcentaje de AGPI-CL fue mayor en las ratas de 1 y 6 días de edad que en las de 12 y 20 días (16-17% vs 5%). Por otra parte, la incorporación de 1-14C ácido linoleico fue más alta en el hígado que en el TAM, aunque la relación "productos desaturados de 1-14C ácido linoleico / 1-14C ácido linoleico" fue mayor en el TAM que en el hígado (>4), lo cual podría indicar que este tejido además de almacenar AGPI-CL los sintetiza. En resumen, nuestros resultados demuestran que el TAM es depósito importante de AGPICL durante el período de máximo desarrollo postnatal del cerebro.

Oxidación de las lipoproteínas de alta y baja densidad del plasma humano y su correlación con la composición de ácidos grasos de los fosfolípidos / Low and hight density lipoproteins oxidation of the human plasma and your correlacionated with fatty acids of the phospholipids

La modificación oxidativa de las lipoproteínas de baja densidad (LDL) está asociada con el desarrollo de la aterosclerosis. El propósito del presente estudio es investigar cual de los ácidos grasos (AG) componentes de los fosfolípidos (FL) de las LDL y de las lipoproteínas de alta densidad (HDL) está relacionado con su susceptibilidad de oxidación (SO). Las LDL y HDL fueron aisladas del plasma de 13 voluntarios e incubadas con CuSO45uM por 3 h. a 37 ºC. El grado de oxidación fue medido por la producción de sustancias reactivas con el ácido tiobarbitúrico (TBARS) y correlacionado con la relación por ciento AG respecto por ciento ácido palmítico de los FL. Encontrándose en la LDL una correlación estadísticamente significativa (p<0,05) para el C22:6 y C20:4 y en la HDL para el C22:6 y C20:5. En conclusión la SO de las LDL y HDL está correlacionada con ácidos grasos poliinsaturados de sus FL.

LIPSIA--a new software system for the evaluation of functional magnetic resonance images of the human brain.

This paper describes the non-commercial software system LIPSIA that was developed for the processing of functional magnetic resonance images (fMRI) of the human brain. The analysis of fMRI data comprises various aspects including filtering, spatial transformation, statistical evaluation as well as segmentation and visualization. In LIPSIA, particular emphasis was placed on the development of new visualization and segmentation techniques that support visualizations of individual brain anatomy so that experts can assess the exact location of activation patterns in individual brains. As the amount of data that must be handled is enormous, another important aspect in the development LIPSIA was the efficiency of the software implementation. Well established statistical techniques were used whenever possible.

On multivariate spectral analysis of fMRI time series.

Most of functional magnetic resonance imaging (fMRI) time series analysis is based on single voxel data evaluation using parametric statistical tests. The result of such an analysis is a statistical parametric map. Voxels with a high significance value in the parametric test are interpreted as activation regions stimulated by the experimental task. However, for the investigation of functional connectivities it would be interesting to get some detailed information about the temporal dynamics of the blood oxygen level-dependent (BOLD) signal. For investigating that behavior, a method for fMRI data analysis has been developed that is based on Wiener theory of spectral analysis for multivariate time series. Spectral parameters such as coherence measure and phase lead can be estimated. The resulting maps give detailed information on brain regions that belong to a network structure and also show the temporal behavior of the BOLD response function. This paper describes the method and presents a visual fMRI experiment as an example to demonstrate the results.

Gestalt perception modulates early visual processing.

We examined whether early visual processing reflects perceptual properties of a stimulus in addition to physical features. We recorded event-related potentials (ERPs) of 13 subjects in a visual classification task. We used four different stimuli which were all composed of four identical elements. One of the stimuli constituted an illusory Kanizsa square, another was composed of the same number of collinear line segments but the elements did not form a Gestalt. In addition, a target and a control stimulus were used which were arranged differently. These stimuli allow us to differentiate the processing of colinear line elements (stimulus features) and illusory figures (perceptual properties). The visual N170 in response to the illusory figure was significantly larger as compared to the other collinear stimulus. This is taken to indicate that the visual N170 reflects cognitive processes of Gestalt perception in addition to attentional processes and physical stimulus properties.

Generation of a flexible cell line with regulatable, high-level expression of HIV Gag/Pol particles capable of packaging HIV-derived vectors.

HIV-derived vectors are of potential clinical relevance due to their ability to transduce nondividing cells in vitro and in vivo. However, the generation of cell lines stably and reproducibly expressing high amounts of defined subviral particles, capable of packaging and transducing HIV-derived vectors, has been hampered by the cytotoxicity of some of the required gene products, in particular of the HIV-1 protease. The successful use of regulatable gene expression systems to overcome this problem requires that the remaining basally expressed gene product activity is below the threshold for cytotoxicity. To try to achieve this, we have consecutively introduced appropriate plasmids, encoding HIV rev and HIV gag/pol gene products, each under the control of separate ecdysone-inducible promoters, into human 293 cells. Using a protocol in which a specific HIV protease inhibitor, Saquinavir, was continuously present in the culture medium during selection, we could generate stable cell lines inducibly expressing high amounts of subviral particles. A cell line, termed 293-Rev/Gag/Pol(i), which has been characterized in more detail, inducibly releases, within 48 h postinduction, high amounts of HIV Gag/Pol particles (about 10 microg CA/ml). These HIV Gag/Pol particles can package and transduce third-generation HIV vectors to high titers. Thus, in addition to other applications, the 293-Rev/Gag/Pol(i) cell line represents a "founder" packaging cell line which, depending on the requirement, can be further modified to include specific transgene-encoding vector and targeting glycoprotein genes.

[Influential factors in mortality rate from congenital heart disease. Study of 1,216 children in the Autonomous Community of Murcia (1978-1990)]. / Factores influyentes en la evolución de la mortalidad de las cardiopatías congénitas. Estudio sobre 1.216 niños en la Comunidad Autónoma de Murcia (1978-1990).

INTRODUCTION: In the last few years, important progress has taken place in management of congenital heart disease. These changes have had an influence on diagnosis, preoperative management, surgery treatment and postoperative care, giving rise to better results in the treatment of children suffering from congenital heart disease. AIM: To assess the results of congenital heart diseases in a reference hospital by comparing two periods with reference to both diagnosis and therapeutical management. We also intend to investigate the influence that factors such as the existence of extracardiac congenital malformations and heart surgery have on mortality. PATIENTS AND METHODS: Our sample group was made up of 1,216 children suffering from congenital heart disease. Their ages ranged from 1 day to 7 years old. These children were born over a period of thirteen years and studied at the paediatric cardiology unit in a reference hospital in the Autonomous Community of Murcia, a region of Spain. We retrospectively analysed their development by individual heart diseases (and their associated factors), and the global results. Our research was divided into two periods: between 1978 and 1983, and between 1984 and 1990. Differences were found regarding diagnosis and treatment. RESULTS: a) Mortality rate from congenital heart disease decreased in the period between 1984 and 1990 in comparison to the period between 1978 and 1983, from 28 to 21,7% (p < 0.05); b) individually, the mortality rate decreased with statistical significance in two diseases: interventricular communication and patent ductus arteriosus, and c) there is a higher mortality rate of patients with no surgery treatment and/or extracardiac malformations. CONCLUSION: Progress in the management of congenital heart disease has led to a more favourable outcome in the last years.

Slow cortical potentials during retention of object, spatial, and verbal information.

We used event related potentials (ERPs) to examine both the specificity and the timing of slow cortical scalp potentials (SPs) elicited by the retention of object, spatial, and verbal information in working memory (WM). Participants performed a modified delayed matching task in which a task cue presented in the middle of the delay interval indicated what type of information had to be retained for a subsequent comparison with the test stimulus. The first experiment used nameable objects and spatial locations as stimuli. The retrieval mode (visual vs. verbal) was manipulated by presenting either figural information or printed words as test stimuli. Transient ensembles of frontal and parieto-occipital slow waves with different scalp topographies for object and spatial information were evoked as a function of task cues. When words rather than objects were used as test stimuli highly similar, though more pronounced, fronto-parietal slow wave patterns were obtained. The second experiment using unfamiliar objects and non-nameable spatial locations indicated that neither the left frontal negative SP nor the posterior SPs are exclusively related to verbal working memory operations. The results indicate that a parietal negative SP reflects processes of spatial selective attention whereas a parieto-occipital positive SP indexes the retention of visual object information. Left frontal negative SPs are generated by a compound of higher order frontal control processes and vary as a function of information type.

Properties of wild-type, C-terminally truncated, and chimeric maedi-visna virus glycoprotein and putative pseudotyping of retroviral vector particles.

We have characterized the properties of the maedi-visna virus (MVV) glycoprotein, which has a long cytoplasmic C-terminal domain, and of a panel of C-terminally truncated and C-terminally chimeric MVV-Env constructs. Cells expressing wild-type MVV glycoprotein form syncytia with target cells from many different species and tissues, demonstrating that the MVV-Env cellular receptor is widely distributed. Similar to the situation with other lentiviral glycoproteins, truncation of the C-terminal domain of MVV-Env significantly increases its membrane fusion capacity. However, despite their presence in a fusogenic form at the cell surface, neither the wild-type nor any of the C-terminally modified MVV-Env constructs, these latter lacking sterically inhibitory C termini, were able to successfully pseudotype murine leukemia virus- or human immunodeficiency virus-derived vector particles.