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J Esparza

Publications and source records attributed to J Esparza.

At least 19 recordsLinked to original sources
PubMed2005

Cost effectiveness and delivery study for future HIV vaccines.

Research teams from five countries, Brazil, China, Kenya, Peru and Thailand, have initiated a policy-maker survey on vaccine delivery, cost studies for future HIV vaccination programmes, and associated simulation modeling exercises analysing the relative cost-effectiveness of potential HIV vaccination strategies. The survey assesses challenges and opportunities for future country-level HIV vaccination strategies, providing data on the vaccine characteristics (e.g. vaccine efficacies for susceptibility, infectiousness and disease progression) and vaccination programme strategies to be considered in the cost-effectiveness modeling analyses. The study will provide decision-makers with modeling data on vaccination policy considerations that will assist in developing country-level capacities for future HIV vaccine policy adoption and effective delivery systems, and will help delineate the long-term financial requirements for sustainable HIV vaccination programmes. The WHO-UNAIDS HIV Vaccine Initiative and the collaborating researchers welcome comments or questions from policy makers, health professionals and other stakeholders in the public and private sectors about this effort to help advance policy and capacity related to future potential HIV vaccines.

AIDS Vaccines↗
PubMed2004

Breaking new ground--are changes in immunization services needed for the introduction of future HIV/AIDS vaccines and other new vaccines targeted at adolescents?

A safe, effective and accessible preventive vaccine is our best long-term hope for the control of the HIV/AIDS pandemic. Once the first generation of HIV vaccines are developed, many questions remain unanswered regarding their administration. For instance, which vaccines should be given to whom at what age and how many doses? We argue that pre- and early-adolescents will be one of the main target groups for future HIV vaccines, that is, before the age of exposure to the virus. Historically, immunization has mainly focused on infants. Indeed, vaccines have only occasionally been systematically targeted at adolescents, even in industrialized countries. Delivering vaccines to pre-adolescents and adolescents in developing countries would, to a great extent, be a new challenge. But it is not just HIV/AIDS vaccines that are coming down the pipeline. Herpes simplex type2 (HSV-2) and human papillomavirus (HPV) vaccines are also among the exciting candidate vaccines that may be the agents of change needed to encourage even the poorest countries to develop strategies for reaching adolescents with vaccines and other health services in the coming decade. Together, they may also provide the impetus for changing the paradigm for how vaccines are administered. Not only will more antigens be included in national immunization schedules, but the age of target groups will range much more widely than at present, encompassing older children, adolescents and young adults. While presenting major difficulties for delivery, these new ingredients also offer stimulating opportunities to completely rethink how vaccines are presented, administered and delivered. We predict that even the poorest countries will be looking to developing integrated, sustainable strategies for reaching pre-adolescents and adolescents with vaccines in the coming decade.

AIDS Vaccines↗
PubMed2004

[Brainstem gliomas].

Brainstem gliomas have been increasingly understood in the last two decades and they are nowadays regarded as an heterogeneous group of tumors with tendency towards the pediatric age, where they account for 10-20% of brain neoplasms. Besides the well known diffuse tumor, several subtypes, with a different biological behaviour, amenable to surgical resection and better prognosis, have been identified, giving rise to many classifications and terms. In the other way, attention has been recently paid to adult brainstem gliomas in contrast to pediatric tumors. Based on a review of the literature, we describe the different subtypes of brainstem gliomas, with particular interest on therapeutic approaches and differences between pediatric and adult tumors, employing iconography from our series.

Adult↗
PubMed2003

Public health considerations for the use of a first generation HIV vaccine. Report from a WHO-UNAIDS-CDC consultation, Geneva, 20-21 November 2002.

SUMMARY: To accelerate the development and future availability of safe, effective and affordable HIV vaccines it is essential to address not only the associated biomedical obstacles, but also the logistic aspects that would guide the introduction and use of those vaccines. It is likely that initial vaccines may only be partially effective, and their public health use will have to be carefully considered. This report summarizes the discussions from a consultation held in Geneva (20-21 November 2002) organized by the World Health Organization (WHO), the joint United Nations Programme on HIV/AIDS (UNAIDS) and the US Centers for Disease Control and Prevention (CDC). The group identified a number of logistic issues that need to be addressed to accelerate the development and future availability of HIV vaccines, and made broad recommendations in four different areas: (a) Vaccine manufacturing and licensing; (b) vaccination acceptability and social marketing; (c) immunisation strategies and delivery; and (d) access and economic issues. The implementation of these recommendations will require the participation of multiple stakeholders in the public and private sector, in industrialized and developing countries. These actions will be essential to ensure widespread and rapid access to HIV vaccines globally, soon after their efficacy is demonstrated in clinical trials.

AIDS Vaccines↗
PubMed2003

Fronto-orbital remodeling without orbito-naso-frontal bandeau.

INTRODUCTION: Fronto-orbital bilateral advance is the procedure of choice for the treatment of craniosynostosis affecting most of the anterior area of the skull and orbitomalar regions. The aim of the technique is to achieve a supra-orbital bilateral bar and a frontal bone. We have introduced a modification in order to simplify the technique. PATIENTS AND METHODS: From November 1998 to January 2002, 18 patients with craniosynostosis have been surgically treated using our technique. The mean age when the treatment was performed was 6.93 months (range 3 to 22 months). Brain computed tomography (CT) scans and three-dimensional (3-D) reconstruction of CT scans were performed before and after treatment. SURGICAL TECHNIQUE: A bifrontal craniotomy was performed taking the osteotomy up to the supraorbital rim. A new frontal bone was obtained from another region of the cranium creating new orbital edges. The osteosynthesis was conducted using absorbable materials. RESULTS: The follow-up of the patients ranged from 3 months to 3 years. All patients were studied using CT scans and 3-D reconstruction of CT after treatment, which demonstrated the persistence of the fronto-orbital advance. No secondary complications related to the new technique were found in any of the patients. CONCLUSIONS: The frontal-orbital advance obtained was stable. The technique was simplified by not creating a supraorbital bar and by reducing the bone fixation points. The manipulation of both frontal lobes and orbital globes was negligible. The aesthetic results were excellent.

Bone Remodeling↗
PubMed2003

[Congenital brain tumors: nine cases and review of the literature].

OBJECTIVE: To review congenital brain tumors patients younger than 2 months diagnosed in our Department. PATIENTS AND METHODS: Nine congenital brain tumors were diagnosed between 1983 and 2001 among a consecutive serie of 484 paediatric cerebral tumors (patients less than 15 years). Clinical and radiological findings and prognostic factors are analyzed. RESULTS: There were two teratomas, two glioblastomas, one xanthogranuloma affecting cavernous sinus, one supratentorial PNET and one medulloblastoma and one oligodendroglioma. In one case histological diagnosis was not possible. In four cases antenatal diagnosis was done by means of ultrasonography and MRI. Seven patients were operated on, with one intraoperative exitus. Five patients died due to tumoral progression in the first two months after surgery. Another case was considered not amenable for surgical resection, and thus was not operated. He died in the fifth day of life. Three patients are alive 14, 36 and 72 months after surgery, one with severe psicomotor delay, another one with normal mental status but dependent on seizures medication and the last one with mild mental delay. In the last case of our serie intrauterine death happened by 33(rd )week and histological diagnosis was not possible. CONCLUSIONS: Prognosis for congenital brain tumors depends on the operative morbidity and tumor histology. However final prognosis in these patients is still discouraging, despite early surgery and operative and anaesthetic improvements.

Adult↗
PubMed2003

HIV vaccines: a global perspective.

Twenty years after its recognition, HIV/AIDS has become the most important infectious disease globally and the leading cause of death in Africa. A preventive vaccine represents the best long-term hope for its control. The development of such a vaccine, however, has encountered a number of scientific challenges, including the lack of information on immune correlates of protection, the limitations in our understanding of the relevance of primate protection experiments in relation to vaccine-induced protection in humans, and the significance of genetic and immunologic variability of HIV strains for potential vaccine efficacy. Despite these uncertainties, the first phase I trial of an HIV vaccine was conducted in the United States in 1987. Since then more than 30 candidate vaccines have been tested in over 70 phase I/II clinical trials in both industrialized and developing countries. The first HIV vaccine trial in a developing country was conducted in 1993, six years after the first trial in the United States. Since then eighteen phase I/II trials and one phase III trial have been or are being conducted in developing countries, and additional phase II and III trials are planned to start in 2003. Most of these initial trials have been conducted in Thailand, but more recently trials have been initiated in Africa, Latin America and the Caribbean. Over the past years, the HIV vaccine development effort has followed three major overlapping paradigms. The first "wave" of candidate vaccines aimed at inducing neutralizing antibodies. The second wave focused on stimulation of CD8+ T-cell responses. The current "wave" of HIV vaccine research is aimed at optimizing both humoral and cell-mediated immune responses. The first generation of candidate vaccines (based on the HIV envelope protein) entered phase III efficacy evaluation in 1998, and definitive results from these trials will become available in 2003. Plans to ensure wide access to future HIV vaccines must be developed well in advance.

AIDS Vaccines↗
PubMed2003

[Analysis of the emergency system of the Spanish neurosurgical services].

OBJECTIVES: 1)To study the alert system (on call duty) in the Spanish neurosurgical departments and main issues of the emergency neurosurgical attention; 2) To establish common sense criteria for a thorough review of the system; 3) To analyse the effects of the current alert system on neurosurgical planning in Spain from the point of view of aging of Spanish neurosurgeons. MATERIAL AND METHODS: An interview containing 11 items related to the main aspects of the alert system was developed. The interview was sent to 51 departments. Answer from 42 of them were received. Neurosurgical departments were categorized in two different patterns to analyse the results: 1 st )according to the size of the staff. Three different types were observed:Type A (more than 10 neurosurgeons);Type B (between 6 and 10), and Type C (less than 6). 2 nd ) according to qualification of the personnel receiving the patient in the emergency area:Type I (the patient is received by paramedic personnel);Type II (trainee sends patient to specialist);Type III (training doctor orders diagnostic procedures) and Type IV (neurosurgeon orders diagnostic procedures and decides next actions). RESULTS: Type A departments :This group is formed by 8 departments. Alerts are always mix (at home or in hospital). There are usually 3 neurosurgeons on call (sometimes 4). Staff personnel is on call duty at the hospital 5 days a month plus 5-6 days at home. In 38% of the hospitals, department is type I-II (the patient is initially attended by paramedic personnel, not responsible for diagnostic or treatment). Surgical emergencies account for 0.54 a day as a rule and 12.75 patients require neurosurgeon's attention every day. In 75% of the hospital the neurosurgeon must also read neuroimaging procedures and suture scalps in 37%. Next day, neurosurgeon on call is off duty almost routinely. Type B :it was formed by 21 services. Alert are always mix (at home or in hospital). There are usually two neurosurgeons on call. Staff personnel are on call 4-5 days a month at the hospital and 5-6 days at home. The patient is initially attended by a doctor starting diagnosis in 85% of the cases (types III and IV).They operate 0.52 times a day,attending 6.19 patients/day as a mean. Neurosurgeon must read neuroimaging procedures in 57%. They do not repair scalps (except for a 5%) and personnel is off duty next day routinely. Type C :Nine (9) departments were grouped under this lining. Staff is always on call at home. There is usually only one neurosurgeon (sometimes two). Staff perform 10-12 alerts at home along the month. In 4 of the departments they must duplicate the number of days as far as there are two of them on-call. Patients are attended initially as type III-IV in 100% of the cases (doctor asks for diagnostic tools and decides therapy in 78%). Neurosurgeon on-call receives 4-5 phone-calls a day. Surgical emergencies account for 0.34 a day and 1.84 patients a day are attended directly by them. They never suture scalps. They seldom are off-duty next day. Aging of the Spanish neurosurgeons (389 interviewed). Most important issues are: 152 neurosurgeons will be 55 yo between 2003 and 2008, so they can ask for leaving on-call duties. 121 neurosurgeons will be 65 yo between 2009 and 2013. CONCLUSIONS: 1 st ) Alert system, mostly in bigger departments, is disproportioned and does not to fit to reality. 2 nd ) Emergency is worse organized in bigger hospitals. Besides, neurosurgeon on-call is not properly consulted. 3 rd ) Almost routinely neurosurgeons are offduty the day after alert in hospital. 4 th ) 152 neurosurgeons are necessary in the next five years to maintain the current system, which is obviously unviable. 5 th ) Most of the finishing trainees (residents) should tolerate "on-call contracts"in bigger departments to sustain the actual system. 6 th )For future planning, Neurosurgical National Committee must offer 20 training places a year to fill jubilees to happen from 2009 on. Finally we believe that the current alert system cannot be maintained any more, so Health Administratt system cannot be maintained any more, so Health Administrations must develop a profound reform. In this sense, the role that Local Neurosurgical Societies must play is essential.

Adult↗
PubMed2002

Intraventricular cavernoma in pediatric age.

INTRODUCTION: Cavernomas rarely occur in the ventricular system. Only 10 pediatric cases out of 46 well-documented cases have been published. CASE REPORT: We report the case of an 11-year-old girl operated on for a voluminous cavernoma at the ventricular trigone which was diagnosed after absence seizures. CONCLUSION: Interestingly, the case we report showed a hypointense rim on T2-weighted magnetic resonance images which has not been a common finding in the cases previously reported.

Cerebral Ventricle Neoplasms↗
PubMed2002

Surgical treatment of trigonocephalies and associated hypoteleorbitism.

Premature closure of metopic suture is a relatively uncommon form of craniosyostosis with an estimated incidence of 0,3 per 1000 live births, comprising about 7% of surgical craniosynostosis referred to craniofacial centers. A broad phenotypical spectrum spreads from minor metopic ridges to severe trigonocephaly with pterional indentation supraorbital bar retrusion, temporal and parietal compensating bossings and hypotelorism. Most of the cases arise spontaneously although autosomal dominant inheritance has been described and association with cromosomal abnormalities and different syndromes has been widely reported. Surgical correction has been attempted with good cosmetic results using several variations of the standard frontoorbitary advance. However there is still a number of questions to be solved in relation to this entity, mainly on its pathogenesis, but also on its development, natural history and treatment. Direct surgical approach to associated hypotelorism is a matter of argument when considering the reestablishment of normal interorbitary distances. We have conducted a retrospective analysis of our serie consisting of twenty-eight cases of trigonocephalies. Surgical correction of hypotelorism was attempted in eleven cases while the resting seven children remained "not treated". The objective was to review the functional outcome and cosmetic results comparing the different techniques applied to the frontal bone and to observe evolution of the hypoteleorbitism after the treatment with or without osteotomies and grafting of the nasoethmoidal area.

Child, Preschool↗
PubMed2002

[Early surgery in Poland syndrome].

Poland's congenital malformation presents a variable grade of complexity, depending upon the extent of the muscular and chondro-costal defect. Surgical repair for cosmetic reasons only, may be performed during childhood or puberty due to the absence of symptoms. However, this does not occur when the costal defects has a considerable size, with pulmonary herniation and impairment of respiratory function. In this cases, early surgical correction is preferred in order to adequately stabilize the chest wall. In this paper we present our experience of early surgical treatment in 5 patients affected by a complex syndrome, that were treated with autologous costal transplants and the use pof polytetrafluoroethylene to cover the chest wall defect. We discuss the surgical procedure performed, as well as the advantages of this material with respect to others described up to date and the good results obtained in one of the cases followed-up for five years.

Child, Preschool↗
PubMed2001

Equal aspiration rates in gastrically and transpylorically fed critically ill patients.

OBJECTIVES: To determine the difference in aspiration rates between gastrically and transpylorically fed patients in the intensive care unit. DESIGN: A prospective controlled study of critically ill patients randomized to receive either a gastrically placed feeding tube or a transpylorically placed feeding tube. SETTING: University teaching hospital's medical intensive care unit. The study was conducted over 14 months. PATIENTS: Fifty-four critically ill subjects (with an overall 40% mortality) with similar baseline age, severity of illness, and nutritional needs requiring enteral nutrition, with 51 completing the study. INTERVENTIONS: All feeds were tagged with technetium-99m radiolabeled sulfur colloid, and the pulmonary secretions or lungs of each patient were scanned on a daily basis to determine whether aspiration had occurred. Patients were fed according to their assigned tube placement which was verified daily by continuous electromyography. MEASUREMENTS AND RESULTS: Of 27 gastrically fed patients 2 (7%) had evidence of scanned feed in pulmonary secretions or the lung, compared to 3 of 24 (13%) transpylorically fed patients (n.s.). Clinical suspicion of aspiration was insensitive and detected only 60% of isotopically documented aspirations with a positive predictive value of 27%. CONCLUSION: There was no difference in aspiration rates between gastrically and transpylorically fed critically ill patients.

APACHE↗
PubMed2001

[Treatment with intrapleural streptokinase for coagulated hemothorax after cardiac surgery with cardiopulmonary bypass].

INTRODUCTION AND OBJECTIVES: Coagulated hemothorax is a complication of cardiac surgery with cardiopulmonary bypass. The objective of this study was to present the authors' experience in the intrapleural infusion of streptokinase for the treatment of this complication. METHODS: From January 1996 to June 1999, nine patients (6 males, 3 females, age range: 1-75 years) were clinically and radiographically diagnosed with coagulated hemothorax after cardiac surgery. All patients were treated with intrapleural infusion of streptokinase at a standard dose of 250,000 units in adult patients and 12,000 U/kg in pediatric cases. In cases of occluded chest drainage, the position of the patient was changed and drainage was opened. RESULTS: In all the cases clinical and radiological improvement was observed and 100 to 200 ml of hemothorax was obtained on drainage. One patient died of multiorgan failure due to the underlying disease not related to the procedure. No alteration were observed in hematological tests including coagulation. The other 8 patients were discharged from hospital and remain without pulmonary compromise to date. CONCLUSION: Treatment of coagulated hemothorax with intrapleural infusion of streptokinase is a useful procedure and avoid the need for surgical drainage of hemothorax.

Adult↗
PubMed2001

[Endoscopic treatment of suprasellar arachnoid cysts].

Arachnoid cysts account for only 1% of all intracranial space-occupying lesions. In adults suprasellar cysts represent 9% of all the arachnoid cysts while in pediatric population this percentage reaches 15%. In spite of being a problem relatively common in daily neurosurgical practice there are still a number of questions to be solved concerning pathogenesis and evolution, natural history and treatment. Located in the suprasellar cistern and closely related to the ventricular system, suprasellar arachnoid cysts conform a perfect indication for endoscopic treatment. The development and spreading of neuroendoscopic techniques have surpassed the standard microsurgical approaches as an elective treatment. However there is still controversy on the management of associated hydrocephalus, need for cystoperitoneal shunt after endoscopic fenestration or the superiority of ventriculocystocisternostomy over simple ventriculocystostomy. The authors present a serie of seven consecutive patients with "de novo" diagnosis of suprasellar arachnoid cyst. In every case the treatment consisted in endoscopic fenestration and removal of the cyst membranes, with or without associated ventriculostomy of the IIIrd ventricle. Preoperative symptoms improved in all the patients and five out of seven remain shunt free. One patient maintains a cystoperitoneal shunt and another one, previously shunted, remains shunt dependent. The clinical presentation and postoperative evolution are commented with discussion on the alternative therapeutic options from the endoscopic point of view.

Arachnoid Cysts↗
PubMed2001

An HIV vaccine: how and when?

The best long-term hope for controlling the human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) pandemic is a safe, effective and affordable preventive vaccine, but its development has encountered unprecedented scientific challenges. The first phase I trial of an HIV vaccine was conducted in 1987. Subsequently, more than 30 candidate vaccines have been tested in over 60 phase I/II trials, involving approximately 10 000 healthy volunteers. Most of these trials have been conducted in the USA and Europe, but several have also been conducted in developing countries. The first phase III trials began in the USA in 1998 and in Thailand in 1999 to assess the efficacy of the first generation of HIV vaccines (based on the HIV envelope protein, gp120); the results will be available within the next 1-2 years. To accelerate the development of an HIV vaccine, additional candidate vaccines must be evaluated in parallel in both industrialized and developing countries. This will require international collaboration and coordination and critical ethical issues will need to be addressed. To ensure that future HIV vaccines contribute to the overall HIV/AIDS prevention effort, we should begin planning now on how best to use them.

AIDS Vaccines↗
PubMed2000

Accelerating the development and future availability of HIV-1 vaccines: why, when, where, and how?

An HIV-1 vaccine offers the best long-term hope to control the AIDS pandemic, especially in less-developed countries. To ensure its future availability we need to increase our research efforts today, including clinical trials. Although small-scale clinical trials of HIV-1 vaccines have been underway since 1987, the first phase III efficacy trials started only recently in the USA and Thailand. Initial results from these trials will be available within the next 2-3 years, and we must start planning now how vaccines should be used if found to be effective. In the meantime, the continuing promotion of the parallel development and assessment of other candidate vaccines is important. Financial mechanisms should also be developed as an incentive to industry and to ensure equitable distribution of future vaccines in less-developed countries. Moreover, a concerted effort is needed to ensure the development and future availability of appropriate vaccines for Africa.

AIDS Vaccines↗
PubMed2000

Recombinant bacillus Calmette-Guérin as a potential vector for preventive HIV type 1 vaccines.

In August 1997, the World Health Organization (WHO) and the Joint United Nations Programme on HIV/AIDS (UNAIDS) convened an expert working group to discuss current strategies for the development of HIV type 1 vaccines. Based on the recent findings of investigators from Japan's National Institute of Infectious Diseases (NIID) in Tokyo using recombinant bacillus Calmette-Guérin (rBCG) as a potential vectored vaccine for HIV, a recommendation was made that further work in this area is a priority. As a result, the working group reconvened in September 1998 to discuss the progress to date with this vaccine approach, as well as areas of related research to assess the feasibility of a BCG-vectored HIV vaccine. This report summarizes the discussions addressing the available scientific data on the potential use of rBCG as a vector for preventive HIV vaccines, the work necessary to move such candidate vaccines into Phase 1 clinical trials, and recommendations targeted at facilitating the long-term development of rBCG-vectored HIV vaccines.

AIDS Vaccines↗