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1.
BMC Cancer ; 23(1): 728, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37550634

RESUMEN

BACKGROUND: Surgical resection followed by adjuvant mFOLFIRINOX (5-fluorouracil with leucovorin, irinotecan, and oxaliplatin) is currently the standard of care for patients with resectable pancreatic cancer. The main concern regarding adjuvant chemotherapy is that only half of patients actually receive adjuvant treatment. Neoadjuvant chemotherapy, on the other hand, guarantees early systemic treatment and may increase chemotherapy use and thereby improve overall survival. Furthermore, it may prevent futile surgery in patients with rapidly progressive disease. However, some argue that neoadjuvant therapy delays surgery, which could lead to progression towards unresectable disease and thus offset the potential benefits. Comparison of perioperative (i.e., neoadjuvant and adjuvant) with (only) adjuvant administration of mFOLFIRINOX in a randomized controlled trial (RCT) is needed to determine the optimal approach. METHODS: This multicenter, phase 3, RCT will include 378 patients with resectable pancreatic ductal adenocarcinoma with a WHO performance status of 0 or 1. Patients are recruited from 20 Dutch centers and three centers in Norway and Sweden. Resectable pancreatic cancer is defined as no arterial contact and ≤ 90 degrees venous contact. Patients in the intervention arm are scheduled for 8 cycles of neoadjuvant mFOLFIRINOX followed by surgery and 4 cycles of adjuvant mFOLFIRINOX (2-week cycle of oxaliplatin 85 mg/m2, leucovorin 400 mg/m2, irinotecan 150 mg/m2 at day 1, followed by 46 h continuous infusion of 5-fluorouracil 2400 g/m2). Patients in the comparator arm start with surgery followed by 12 cycles of adjuvant mFOLFIRINOX. The primary outcome is overall survival by intention-to-treat. Secondary outcomes include progression-free survival, resection rate, quality of life, adverse events, and surgical complications. To detect a hazard ratio of 0.70 with 80% power, 252 events are needed. The number of events is expected to be reached after the inclusion of 378 patients in 36 months, with analysis planned 18 months after the last patient has been randomized. DISCUSSION: The multicenter PREOPANC-3 trial compares perioperative mFOLFIRINOX with adjuvant mFOLFIRINOX in patients with resectable pancreatic cancer. TRIAL REGISTRATION: Clinical Trials: NCT04927780. Registered June 16, 2021.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Pancreáticas , Humanos , Irinotecán/uso terapéutico , Oxaliplatino/uso terapéutico , Leucovorina/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/cirugía , Fluorouracilo/uso terapéutico , Terapia Neoadyuvante/métodos , Quimioterapia Adyuvante , Adyuvantes Inmunológicos/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto , Neoplasias Pancreáticas
2.
Updates Surg ; 73(4): 1391-1397, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33770412

RESUMEN

Drain Amylase level are routinely determined to diagnose pancreatic fistula after Pancreatocoduodenectomy. Consensus is lacking regarding the cut-off value of amylase to diagnosis clinically relevant postoperative pancreatic fistulae (POPF). The present study proposes a model based on Amylase Value in the Drain (AVD) measured in the first three postoperative days to predict a POPF. Amylase cut-offs were selected from a previous published systematic review and the accuracy were validated in a multicentre database from 12 centres in 2 countries. The present study defined POPF the 2016 ISGPS criteria (3 times the upper limit of normal serum amylase). A learning machine method was used to correlate AVD with the diagnosis of POPF. Overall, 454 (27%) of 1638 patients developed POPF. Machine learning excluded a clinically relevant postoperative pancreatic fistulae with an AUC of 0.962 (95% CI 0.940-0.984) in the first five postoperative days. An AVD at a cut-off of 270 U/L in 2 days in the first three postoperative days excluded a POPF with an AUC of 0.869 (CI 0.81-0.90, p < 0.0001). A single AVD in the first three postoperative days may not exclude POPF after pancreatoduodenectomy. The levels should be monitored until day 3 and have two negative values before removing the drain. In the group with a positive level, the drain should be kept in and AVD monitored until postoperative day five.


Asunto(s)
Fístula Pancreática , Pancreaticoduodenectomía , Amilasas , Drenaje , Humanos , Páncreas/cirugía , Fístula Pancreática/diagnóstico , Fístula Pancreática/etiología , Fístula Pancreática/cirugía , Pancreaticoduodenectomía/efectos adversos , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/cirugía , Factores de Riesgo
3.
BMC Cancer ; 21(1): 300, 2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33757440

RESUMEN

BACKGROUND: Neoadjuvant therapy has several potential advantages over upfront surgery in patients with localized pancreatic cancer; more patients receive systemic treatment, fewer patients undergo futile surgery, and R0 resection rates are higher, thereby possibly improving overall survival (OS). Two recent randomized trials have suggested benefit of neoadjuvant chemoradiotherapy over upfront surgery, both including single-agent chemotherapy regimens. Potentially, the multi-agent FOLFIRINOX regimen (5-fluorouracil with leucovorin, irinotecan, and oxaliplatin) may further improve outcomes in the neoadjuvant setting for localized pancreatic cancer, but randomized studies are needed. The PREOPANC-2 trial investigates whether neoadjuvant FOLFIRINOX improves OS compared with neoadjuvant gemcitabine-based chemoradiotherapy and adjuvant gemcitabine in resectable and borderline resectable pancreatic cancer patients. METHODS: This nationwide multicenter phase III randomized controlled trial includes patients with pathologically confirmed resectable and borderline resectable pancreatic cancer with a WHO performance score of 0 or 1. Resectable pancreatic cancer is defined as no arterial and ≤ 90 degrees venous involvement; borderline resectable pancreatic cancer is defined as ≤90 degrees arterial and ≤ 270 degrees venous involvement without occlusion. Patients receive 8 cycles of neoadjuvant FOLFIRINOX chemotherapy followed by surgery without adjuvant treatment (arm A), or 3 cycles of neoadjuvant gemcitabine with hypofractionated radiotherapy (36 Gy in 15 fractions) during the second cycle, followed by surgery and 4 cycles of adjuvant gemcitabine (arm B). The primary endpoint is OS by intention-to-treat. Secondary endpoints include progression-free survival, quality of life, resection rate, and R0 resection rate. To detect a hazard ratio of 0.70 with 80% power, 252 events are needed. The number of events is expected to be reached after inclusion of 368 eligible patients assuming an accrual period of 3 years and 1.5 years follow-up. DISCUSSION: The PREOPANC-2 trial directly compares two neoadjuvant regimens for patients with resectable and borderline resectable pancreatic cancer. Our study will provide evidence on the neoadjuvant treatment of choice for patients with resectable and borderline resectable pancreatic cancer. TRIAL REGISTRATION: Primary registry and trial identifying number: EudraCT: 2017-002036-17 . Date of registration: March 6, 2018. Secondary identifying numbers: The Netherlands National Trial Register - NL7094 , NL61961.078.17, MEC-2018-004.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia/métodos , Neoplasias Pancreáticas/terapia , Ensayos Clínicos Controlados Aleatorios como Asunto , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Fluorouracilo/administración & dosificación , Humanos , Irinotecán/administración & dosificación , Leucovorina/administración & dosificación , Terapia Neoadyuvante , Oxaliplatino/administración & dosificación , Neoplasias Pancreáticas/mortalidad , Gemcitabina
4.
Pancreatology ; 19(6): 888-896, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31378583

RESUMEN

BACKGROUND: Abdominal drainage and the timing of drain removal in patients undergoing pancreatic resection are under debate. Early drain removal after pancreatic resection has been reported to be safe with a low risk for clinical relevant postoperative pancreatic fistula (CR-POPF) when drain amylase on POD1 is < 5000U/L. The aim of this study was to validate this algorithm in a large national cohort. METHODS: Patients registered in the Dutch Pancreatic Cancer Audit (2014-2016) who underwent pancreatoduodenectomy, distal pancreatectomy or enucleation were analysed. Data on post-operative drain amylase levels, drain removal, postoperative pancreatic fistulae were collected. Univariate and multivariate analysis using a logistic regression model were performed. The primary outcome measure was grade B/C pancreatic fistula (CR-POPF). RESULTS: Among 1402 included patients, 433 patients with a drain fluid amylase level of <5000U/L on POD1, 7% developed a CR-POPF. For patients with an amylase level >5000U/L the CR-POPF rate was 28%. When using a cut-off point of 2000U/L or 1000U/L during POD1-3, the CR-POPF rates were 6% and 5% respectively. For patients with an amylase level of >2000U/L and >1000UL during POD 1-3 the CR-POPF rates were 26% and 22% respectively (n = 223). Drain removal on POD4 or thereafter was associated with more complications (p = 0.004). Drain amylase level was shown to be the most statistically significant predicting factor for CR-POPF (Wald = 49.7; p < 0.001). CONCLUSION: Our data support early drain removal after pancreatic resection. However, a cut-off of 5000U/L drain amylase on POD1 was associated with a relatively high CR-POPF rate of 7%. A cut-off point of 1000U/L during POD1-3 resulted in 5% CR-POPF and might be a safer alternative.


Asunto(s)
Drenaje/métodos , Páncreas/cirugía , Abdomen , Anciano , Algoritmos , Amilasas/análisis , Remoción de Dispositivos/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Países Bajos , Pancreatectomía , Neoplasias Pancreáticas/cirugía , Pancreaticoduodenectomía , Valores de Referencia , Resultado del Tratamiento
5.
World J Surg Oncol ; 13: 266, 2015 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-26338109

RESUMEN

BACKGROUND: The incidence rates for adenocarcinoma of the esophagus are increasing while the prognosis has only improved slightly. There is no apparent benefit in short- and long-term survival after different surgical strategies, but surgery is associated with significant morbidity. The goal of this study is to prospectively assess the quality of life and hospital costs after esophageal resections depending on the development of complications. METHODS: Prospective data was collected from 47 patients undergoing an esophageal resection for esophageal cancer participating in the prospective LAParotomy or LAParoscopy and Adhesions (LAPAD) study (clinicaltrials.gov registration number: NCT01236625). A comparison was made between patients who developed major complications and minor or no complications regarding quality of life and hospital costs. RESULTS: Thirteen patients developed major complications while 34 patients developed only minor or no complications. Patients with major complications had a mean hospital cost of $16,369 vs $12,409 for patients without or with minor complications. We found no difference in quality of life between the two groups 6 months after surgery. CONCLUSIONS: In our cohort, major complications did not seem to have a detrimental effect on postoperative quality of life 6 months after surgery but they increased costs associated with esophageal resection.


Asunto(s)
Adenocarcinoma/economía , Neoplasias Esofágicas/economía , Costos de Hospital , Laparoscopía/economía , Laparotomía/economía , Calidad de Vida , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Anciano , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Femenino , Estudios de Seguimiento , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Prospectivos
6.
Colorectal Dis ; 15(6): e323-9, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23406347

RESUMEN

AIM: Restorative surgery after (procto)colectomy with ileo-neorectal anastomosis (INRA) or restorative proctocolectomy with ileal pouch anal anastomosis (RPC) combines cure of ulcerative colitis (UC) with restoration of intestinal continuity. This study aimed to evaluate these two operations. METHOD: Patients having INRA and RPC were matched according to sex, age at onset of UC, age at restorative surgery and duration of follow-up. Patients were included if they were over 18 years of age, had UC confirmed histopathologically and had undergone either operation. Long-term function, anal and neorectal physiology, complications, quality of life (QoL) and health status (HS) were determined. RESULTS: Seventy-one consecutive patients underwent surgery with the intention of having an INRA procedure. This was successfully carried out in 50, and 21 underwent intra-operative conversion to RPC. Median defaecation frequency was 6/24 h. In 11/71 patients reservoir failure occurred and 13/71 developed pouchitis. QoL and HS were comparable to the healthy population. Median follow-up was 6.2 years. These patients were matched with 71 patients who underwent RPC. RPC was successful in all patients. Median defaecation frequency was 8/24 h. Failure occurred in 7/71 patients and 13/71 developed pouchitis. QoL and HS were comparable with the healthy population. Median follow-up was 6.9 years. CONCLUSION: Comparison of INRA and RPC on an intention to treat basis was not considered to be realistic due to the high intra-operative conversion rate and the failures in the INRA group. RPC remains the procedure of choice for restoring intestinal continuity after proctocolectomy for UC.


Asunto(s)
Colitis Ulcerosa/cirugía , Reservorios Cólicos , Proctocolectomía Restauradora , Adulto , Estudios de Cohortes , Femenino , Estado de Salud , Humanos , Estudios Longitudinales , Masculino , Complicaciones Posoperatorias , Reservoritis , Calidad de Vida , Estudios Retrospectivos , Resultado del Tratamiento
7.
Parasitology ; 134(Pt 10): 1315-27, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17645813

RESUMEN

This study investigated the significance of serum complement on transmission-reducing activity (TRA) of field sera from 24 infected Plasmodium falciparum gametocyte carriers (from Cameroon) against cultured NF54 P. falciparum. Laboratory-reared Anopheles stephensi were given infectious blood meals prepared either with sera from naïve Dutch donor (AB type) or pair-matched field serum samples, both with and without active complement. TRA of serum factors and host complement on mosquito infection rate and oocyst intensity were divided into the various components involved in the early stages of sporogony. The majority (>80%) of sera tested showed positive antibody titres to Pfs230, the relevant complement-dependent target of transmission-reducing mechanisms. Regardless of the presence of active complement, bloodmeals with field sera exhibited significantly lower infection rates and oocyst intensity than the control group. Serological reactivity in Capture-ELISA against Pfs230 was significantly correlated with the reduction of parasite infectivity. Contrary to our expectation, the presence of active complement in the mosquito bloodmeal did not increase parasite losses and therefore the magnitude of transmission reduction by individual immune sera. Our findings on P. falciparum are consistent with previous studies on animal hosts of Plasmodium, indicating that early P. falciparum sporogonic stages may be insensitive to the antibody-dependent pathways of complement in human serum.


Asunto(s)
Anopheles/inmunología , Anopheles/parasitología , Proteínas del Sistema Complemento/inmunología , Plasmodium falciparum/crecimiento & desarrollo , Plasmodium falciparum/inmunología , Suero/química , Suero/inmunología , Animales , Anticuerpos Antiprotozoarios/sangre , Anticuerpos Antiprotozoarios/metabolismo , Interacciones Huésped-Parásitos , Calor , Humanos , Insectos Vectores/inmunología , Insectos Vectores/parasitología , Estadios del Ciclo de Vida , Malaria Falciparum/inmunología , Malaria Falciparum/transmisión , Densidad de Población
8.
Parasitology ; 130(Pt 1): 13-22, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15700753

RESUMEN

Host responses to the transmittable stages of the malaria parasite may reduce transmission effectively. Transmission-reducing activity (TRA) of human serum can be determined as a percentage, using the Standard Membrane Feeding Assay (SMFA). This laboratory assay was evaluated using the results of 121 experiments with malaria-endemic sera among which many repeated measurements were obtained. The assay consists of the feeding of Anopheles stephensi mosquitoes with cultured Plasmodium falciparum gametocytes, mixed with human red blood cells, and control and experimental sera. The TRA of individual sera was determined by the comparison of oocyst densities between these sera. Bootstrap data on oocyst densities in individual mosquitoes in control feeds were used to construct confidence limits for TRA percentages of serum feeds. Low (<20%) and high TRA (>90%) values for individual sera were usually reproduced in a second experiment, whereas this was more difficult for values between 20% and 90%. The observed variability of TRA values is explained in part by the variability in oocyst density per mosquito. Oocyst densities in control feeds varied more between experiments than within experiments and showed a slight decline over the 3 years of experiments. Reproducibility of TRA of field sera was low (20%) between experiments, but much higher (61 %) within experiments. A minimum of 35 oocysts per mosquito in control feeds gave optimal reproducibility (44%) between experiments. We recommend that (1) sera are compared within an experiment, or (2) assays are only analysed where controls have at least 35 oocysts per mosquito. The SMFA is under the recommended conditions appropriate for the study of factors that may influence TRA, e.g. transmission blocking vaccines.


Asunto(s)
Anopheles/parasitología , Conducta Alimentaria/fisiología , Malaria Falciparum/sangre , Malaria Falciparum/transmisión , Membranas Artificiales , Animales , Anopheles/fisiología , Simulación por Computador , Humanos , Insectos Vectores , Malaria Falciparum/prevención & control , Modelos Biológicos , Oocistos , Plasmodium falciparum/crecimiento & desarrollo , Reproducibilidad de los Resultados , Estudios Retrospectivos
9.
Parasite Immunol ; 26(2): 105-10, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15225297

RESUMEN

Transmission blocking immunity (TBI) was studied in relation to age, gametocyte density and transmission intensity. subjects with high gametocytaemias were selected in a hypo-endemic urban district and a hyper-endemic rural area in South Cameroon. TBI was determined in blood from gametocyte carriers in a bioassay (Direct Membrane Feeding Assay), with either autologous plasma (OWN) or control serum (AB). Mosquito infection rates (IR) were compared. infection rates correlated positively with gametocyte and oocyst densities. Three TBI indicators were analysed: the proportion of transmission reducers (IRAB > IROWN, P < 0.01), the mean intensity of TBI (IRAB - IROWN), and the contribution of TBI to total inhibition [(IRAB-IROWN)/(100-IROWN)]. we could not discriminate between areas with regard to either the proportion of transmission reducers (urban 15% and rural 29%) or the mean levels of TBI (urban 10% and rural 9%), or contribution of TBI to total inhibition (urban 10% and rural 13%). there was no relationship between TBI indicators and age, but a trend of increasing values was observed with rising gametocytaemia, which was considered as a confusing factor. a multivariable analysis showed that the probability of being a reducer was 4.6 fold higher in the rural area than in the urban district.


Asunto(s)
Culicidae/fisiología , Culicidae/parasitología , Enfermedades Endémicas , Malaria Falciparum/inmunología , Malaria Falciparum/transmisión , Plasmodium falciparum/patogenicidad , Adolescente , Adulto , Animales , Camerún , Portador Sano/epidemiología , Portador Sano/inmunología , Portador Sano/parasitología , Portador Sano/transmisión , Niño , Preescolar , Conducta Alimentaria , Humanos , Insectos Vectores/parasitología , Insectos Vectores/fisiología , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Plasmodium falciparum/crecimiento & desarrollo , Plasmodium falciparum/aislamiento & purificación , Población Rural , Población Urbana
10.
Thromb Haemost ; 83(2): 191-8, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10739371

RESUMEN

In a direct assay comparison we evaluated the diagnostic performance of 10 novel D-Dimer assays for the exclusion of deep venous thrombosis (DVT). In addition, 3 conventional ELISA D-Dimer assays were included as reference tests. The study was performed in 99 consecutive outpatients referred to the emergency department for clinical suspicion of DVT. Venography was used as reference standard and demonstrated the presence of DVT in 50 patients (6 patients with isolated distal DVT and 44 patients with proximal DVT). The qualitative D-Dimer assays Minutex and SimpliRED and the quantitative BC DD showed overall sensitivities (for proximal and distal DVT) of only 80-83% with specificities that ranged from 87 to 94%. Overall sensitivity was 94% for the qualitative INSTANT I.A. and 98% for the quantitative Turbiquant at a cut-off level equal to the detection limit. Using different cut-off levels a sensitivity of 100% for proximal DVT and for proximal as well as distal DVT could be obtained for NycoCard, IL DD, Liatest, Tinaquant and VIDAS D-Dimer assays with specificities that ranged from 31% (NycoCard) to 71% (VIDAS) for proximal DVT and from 12% (NycoCard) to 47% (IL DD) for overall DVT. At a cut-off level equal to the upper limit of the reference range only Tinaquant and VIDAS showed a sensitivity of 100% for proximal as well as for distal DVT with a specificity of 39% and 41% respectively. The results of this study suggest that the VIDAS and Tinaquant D-Dimer assays have the highest sensitivity for the exclusion of DVT in outpatients. In outpatients that have a low or moderate pretest probability for DVT, these tests may be used in management studies where anticoagulation is withheld on the basis of D-Dimer testing alone.


Asunto(s)
Productos de Degradación de Fibrina-Fibrinógeno/análisis , Trombosis de la Vena/diagnóstico , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Pruebas de Química Clínica/normas , Técnicas de Laboratorio Clínico/normas , Estudios de Cohortes , Medios de Contraste , Diagnóstico Diferencial , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Flebografía/normas , Estudios Prospectivos , Curva ROC , Juego de Reactivos para Diagnóstico/normas , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
11.
Eur J Surg ; 165(5): 507-11, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10391173

RESUMEN

Between 1993 and 1996 nine mentally retarded patients presented because of an acute abdomen. All had the habit of aerophagia, diagnosed previously by a general practitioner. Massive distension of the bowel led to ileus, volvulus, and necrosis. After placement of a percutaneous endoscopic gastrostomy catheter or performing a gastrostomy during laparotomy with the intention to use as a desufflator, no recurrence of the signs and symptoms of an acute abdomen were observed.


Asunto(s)
Abdomen Agudo/etiología , Aerofagia/complicaciones , Discapacidad Intelectual , Adulto , Femenino , Humanos , Masculino
12.
J Virol ; 73(4): 3292-300, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10074183

RESUMEN

The kinetics of T-helper immune responses generated in 16 mature outbred rhesus monkeys (Macaca mulatta) within a 10-month period by three different human immunodeficiency virus type 1 (HIV-1) vaccine strategies were compared. Immune responses to monomeric recombinant gp120SF2 (rgp120) when the protein was expressed in vivo by DNA immunization or when it was delivered as a subunit protein vaccine formulated either with the MF59 adjuvant or by incorporation into immune-stimulating complexes (ISCOMs) were compared. Virus-neutralizing antibodies (NA) against HIV-1SF2 reached similar titers in the two rgp120SF2 protein-immunized groups, but the responses showed different kinetics, while NA were delayed and their levels were low in the DNA-immunized animals. Antigen-specific gamma interferon (IFN-gamma) T-helper (type 1-like) responses were detected in the DNA-immunized group, but only after the fourth immunization, and the rgp120/MF59 group generated both IFN-gamma and interleukin-4 (IL-4) (type 2-like) responses that appeared after the third immunization. In contrast, rgp120/ISCOM-immunized animals rapidly developed marked IL-2, IFN-gamma (type 1-like), and IL-4 responses that peaked after the second immunization. To determine which type of immune responses correlated with protection from infection, all animals were challenged intravenously with 50 50% infective doses of a rhesus cell-propagated, in vivo-titrated stock of a chimeric simian immunodeficiency virus-HIVSF13 construct. Protection was observed in the two groups receiving the rgp120 subunit vaccines. Half of the animals in the ISCOM group were completely protected from infection. In other subunit vaccinees there was evidence by multiple assays that virus detected at 2 weeks postchallenge was effectively cleared. Early induction of potent type 1- as well as type 2-like T-helper responses induced the most-effective immunity.


Asunto(s)
Vacunas contra el SIDA/inmunología , Síndrome de Inmunodeficiencia Adquirida/inmunología , Proteína gp120 de Envoltorio del VIH/inmunología , VIH-1/inmunología , ISCOMs/inmunología , Inmunidad Celular , Polisorbatos/farmacología , Escualeno/inmunología , Escualeno/farmacología , Vacunas contra el SIDA/química , Vacunas contra el SIDA/farmacología , Síndrome de Inmunodeficiencia Adquirida/prevención & control , Adyuvantes Inmunológicos/farmacología , Animales , Química Farmacéutica , Proteína gp120 de Envoltorio del VIH/farmacología , Humanos , ISCOMs/farmacología , Macaca mulatta , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/farmacología
13.
AIDS ; 12(5): F15-22, 1998 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-9543435

RESUMEN

OBJECTIVES: To investigate whether immunization with recombinant HIV-1 envelope protein derived from a clinical isolate could protect macaques from infection with an in vivo passaged chimeric simian-human immunodeficiency virus (SHIV). DESIGN AND METHODS: A total of 16 animals were studied from which three groups of four animals were immunized with vaccine formulations of the CC-chemokine receptor-5-binding recombinant gp120 of HIV-1W6.1D. Four weeks after the last immunization, all 16 animals were intravenously challenged with in vivo passaged SHIV derived from the same HIV-1 group B clinical isolate (W6.1D) as the vaccines. RESULTS: Vaccine protection from infection was demonstrated in 10 out of 12 macaques immunized with recombinant gp120. Complete protection from infection was achieved with all of the animals that received the SBAS2-W6.1D formulation, a potent inducer of both T-cell and humoral immune responses. Partial protection was achieved with SBAS1-W6.1D, a formulation based on immunomodulators known to induce T-cell responses in humans. In vaccinated animals that were infected, virus load was reduced and infection was delayed. CONCLUSIONS: In a relatively large number of primates, vaccine efficacy was demonstrated with a clinically relevant HIV-1 vaccine. These results reveal that it is possible to induce sterilizing immunity sufficient to protect from infection with SHIV which was passaged multiple times in vivo. Our findings have implications for current HIV-1 clinical vaccine trials and ongoing efforts to develop safe prophylactic AIDS vaccines.


Asunto(s)
Vacunas contra el SIDA , Proteína gp120 de Envoltorio del VIH/inmunología , Infecciones por VIH/prevención & control , VIH-1/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Vacunas Sintéticas , Vacunas contra el SIDA/inmunología , Animales , Afinidad de Anticuerpos , Quimera , Anticuerpos Anti-VIH/biosíntesis , Infecciones por VIH/inmunología , Inmunidad Celular , Macaca mulatta , Pruebas de Neutralización , Reacción en Cadena de la Polimerasa , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/prevención & control , Virus de la Inmunodeficiencia de los Simios/genética , Vacunación , Vacunas Sintéticas/inmunología
14.
J Hepatol ; 27(5): 890-3, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9382977

RESUMEN

BACKGROUND/AIMS: The purpose of the study was to investigate the incidence of and risk factors for splenic artery aneurysms in liver transplant patients. METHODS: Medical records and the pre- and 1-year postoperative angiograms of 337 liver transplant patients were reviewed to assess the presence and characteristics of these aneurysms. RESULTS: Forty-five patients with aneurysms were identified (13%): 41 cases in 242 adult patients (17%) and four (4%) in 95 children (p<0.01). The female-to-male ratio was 2:1. The majority of the aneurysms (87%) were located in the distal third of the splenic artery and the majority (87%) of the patients presented multiple aneurysms. In patients without portal hypertension no aneurysms were identified, whereas in 16% of the patients with portal hypertension aneurysms were found (p<0.001). In adult patients the incidence of splenic artery aneurysms was significantly higher in patients with parenchymal diseases than in patients with cholestatic diseases (p<0.0001). Two patients (4%) died due to rupture of the aneurysms. Control angiographies, 1 year after liver transplantation, showed no changes in size and number of the aneurysms, and no new aneurysms were identified. CONCLUSIONS: The incidence of splenic artery aneurysms in liver transplant patients is 13%. They are generally multiple and located in the distal third of the splenic artery. The incidence is higher in women and in patients with parenchymal liver disease and portal hypertension. The incidence of rupture was 4%.


Asunto(s)
Aneurisma/epidemiología , Hepatopatías/complicaciones , Trasplante de Hígado/efectos adversos , Complicaciones Posoperatorias/epidemiología , Arteria Esplénica/fisiopatología , Adolescente , Adulto , Factores de Edad , Anciano , Aneurisma/patología , Angiografía , Niño , Preescolar , Femenino , Humanos , Lactante , Trasplante de Hígado/patología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/patología , Factores de Riesgo , Factores Sexuales
15.
Cancer Immunol Immunother ; 43(1): 44-8, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8917635

RESUMEN

Human papillomaviruses (HPV) are present in approximately 95% of all cervical carcinomas and the HPV E6 and E7 genes are continuously expressed in these lesions. There is also circumstantial evidence that often natural immunity against HPV is generated and that this is of influence on HPV-induced lesions. Stimulation of the immune system by proper presentation of relevant HPV antigens might, therefore, lead to a prophylactic or therapeutic immunological intervention for HPV-induced lesions. For this purpose we have expressed the E6 and E7 protein of HPV 16 in an attenuated strain of Salmonella typhimurium (SL3261, aroA mutation), which has been used extensively as a live vector. Live recombinant Salmonella vaccines have the ability to elicit humoral, secretory and cell-mediated immune responses, including cytotoxic T cells, against the heterologous antigens they express. This report describes the construction of recombinant Salmonella strains expressing the HPV 16 E6 and E7 proteins, and the induction of an HPV-16-specific immune response in mice after immunization with these live vectors.


Asunto(s)
Vacunas Bacterianas/inmunología , Papillomaviridae/inmunología , Vacunas Sintéticas/inmunología , Anticuerpos Antivirales/inmunología , Formación de Anticuerpos , Genes Virales/inmunología , Proteínas Recombinantes/inmunología , Recombinación Genética , Infecciones por Salmonella/inmunología , Infecciones por Salmonella/prevención & control , Fagos de Salmonella/inmunología , Salmonella typhimurium/genética , Salmonella typhimurium/virología
16.
Virus Res ; 37(1): 13-22, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7483818

RESUMEN

The helper T-cell response to the E7 protein of human papillomavirus type 16 (HPV16) was studied using BALB/c (H-2d) mice. Twenty-two overlapping synthetic peptides spanning the HPV16 E7 protein were split into 6 groups. Mice were sensitized using mixtures of synthetic peptides corresponding to each of the groups. Lymph node cell suspensions were cultured with the corresponding mixture of synthetic peptides that was used for sensitization. Two mixtures induced a proliferative response. Analysis of the individual peptides from these mixtures showed that two (overlapping) peptides induced a proliferative response. This response was mediated by CD4+ cells. The common region of the two peptides was found to be a single epitope, and a minimal epitope was demonstrated (AHYNIVTFCCK). In conclusion, in contrast to others, we demonstrated a helper T-cell response in BALB/c mice. This may be due to the fact that we used synthetic peptides as immunizing agent. The helper T-cell epitopes in HPV16 E7 demonstrated previously are partly overlapping with the (minimal) epitope demonstrated here, underlining the 'public' nature of the epitope.


Asunto(s)
Antígenos Virales/inmunología , Epítopos/inmunología , Proteínas Oncogénicas Virales/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Secuencia de Aminoácidos , Animales , Células Cultivadas , Humanos , Ganglios Linfáticos/citología , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Proteínas E7 de Papillomavirus , Péptidos/síntesis química , Péptidos/inmunología
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