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1.
Int J Pharm ; 605: 120785, 2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-34111548

RESUMEN

In recent years, the interest in continuous manufacturing techniques, such as twin-screw wet granulation, has increased. However, the understanding of the influence of the combination of raw material properties and process settings upon the granule quality attributes is still limited. In this study, a T-shaped partial least squares (TPLS) model was developed to link raw material properties, the ratios in which these raw materials were combined and the applied process parameters for the twin-screw wet granulation process with the granule quality attributes. In addition, the predictive ability of the TPLS model was used to find a suitable combination of formulation composition and twin-screw granulation process settings for a new API leading to desired granule quality attributes. Overall, this study helped to better understand the link between raw material properties, formulation composition and process settings on granule quality attributes. Moreover, as TPLS can provide a reasonable starting point for formulation and process development for new APIs, it can reduce the experimental development efforts and consequently the consumption of expensive (and often limited available) new API.


Asunto(s)
Tecnología Farmacéutica , Composición de Medicamentos , Análisis de los Mínimos Cuadrados , Tamaño de la Partícula , Comprimidos
2.
Int J Pharm ; 602: 120642, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33933640

RESUMEN

The potential of torque as in-process control (IPC) to monitor granule size in twin-screw wet granulation (TSG) was investigated. An experimental set-up allowing the collection of granules at four different locations (i.e., in the wetting zone, after the first and second kneading zone and at the end of the granulator) of the granulator screws was used to determine the change in granule size, granule temperature and the contribution of each compartment to the overall torque for varying screw speed, mass feed rate and liquid-to-solid ratio. The only observed correlation was between the granule size and torque increase after the first kneading zone because the torque increase was an indication of the degree in granule growth which was consistently observed with all applied granulation process parameters. No correlation was observed in the other locations as changes of torque were accompanied to either granule breakage and/or growth. Moreover, torque increase was correlated to higher granule temperature, suggesting that energy put into the granulator was partly used to heat up the material being processed and explains additionally the lack of correlation between granule size and torque. Therefore, this study showed that torque could not be used as IPC to monitor granule size during TSG.


Asunto(s)
Calor , Tecnología Farmacéutica , Composición de Medicamentos , Tamaño de la Partícula , Temperatura , Torque , Humectabilidad
3.
Front Genet ; 11: 483, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32499817

RESUMEN

Coccidioides immitis and C. posadasii are soil dwelling dimorphic fungi found in North and South America. Inhalation of aerosolized asexual conidia can result in asymptomatic, acute, or chronic respiratory infection. In the United States there are approximately 350,000 new infections per year. The Coccidioides genus is the only known fungal pathogen to make specialized parasitic spherules, which contain endospores that are released into the host upon spherule rupture. The molecular determinants involved in this key step of infection remain largely elusive as 49% of genes are hypothetical with unknown function. An attenuated mutant strain C. posadasii Δcts2/Δard1/Δcts3 in which chitinase genes 2 and 3 were deleted was previously created for vaccine development. This strain does not complete endospore development, which prevents completion of the parasitic lifecycle. We sought to identify pathways active in the wild-type strain during spherule remodeling and endospore formation that have been affected by gene deletion in the mutant. We compared the transcriptome and volatile metabolome of the mutant Δcts2/Δard1/Δcts3 to the wild-type C735. First, the global transcriptome was compared for both isolates using RNA sequencing. The raw reads were aligned to the reference genome using TOPHAT2 and analyzed using the Cufflinks package. Genes of interest were screened in an in vivo model using NanoString technology. Using solid phase microextraction (SPME) and comprehensive two-dimensional gas chromatography - time-of-flight mass spectrometry (GC × GC-TOFMS) volatile organic compounds (VOCs) were collected and analyzed. Our RNA-Seq analyses reveal approximately 280 significantly differentially regulated transcripts that are either absent or show opposite expression patterns in the mutant compared to the parent strain. This suggests that these genes are tied to networks impacted by deletion and may be critical for endospore development and/or spherule rupture in the wild-type strain. Of these genes, 14 were specific to the Coccidioides genus. We also found that the wild-type and mutant strains differed significantly in their production versus consumption of metabolites, with the mutant displaying increased nutrient scavenging. Overall, our results provide the first targeted list of key genes that are active during endospore formation and demonstrate that this approach can define targets for functional assays in future studies.

4.
Int J Pharm ; 566: 239-253, 2019 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-31103818

RESUMEN

The purpose of this work was to develop a robust hot-melt extrusion and strand pelletization process for manufacturing pellets with an immediate release (IR) of a poorly water-soluble active pharmaceutical ingredient (API), nimodipine. The robustness of pharmaceutical continuous manufacturing processes and of its control strategy is vital for competitiveness to traditional batch-manufacturing. Therefore, first the sensitivity of product quality, process stability, and process monitoring tools to i) parameter changes due to control actions and ii) typical process deviations, i.e., feeding errors, was investigated in a design of experiments (DoE). Thereby, die melt pressure was found to be highly sensitive to composition deviations, i.e. a limiting factor for process stability. Especially critical were deviations to increased HPMC content, since it behaved as a filler in the melt. Pelletization, or pellet size and size distribution respectively, were found to be sensitive to an increased throughput, due to the resulting insufficient strand cooling before the pelletizer. API dissolution in contrast, was found to be robust across the entire investigated range of formulation and process settings. Second, a design space for the production of IR pellets for subsequent tableting was established, and finally, a technical control strategy was developed to ensure a robust process. Near-infrared (NIR) spectroscopy was applied to monitor API content and the sensitivity of the residence time distribution (RTD) was investigated by means of tracer measurements. NIR-based API content monitoring and RTD models for material tracking were found to be at risk after processing melt with high HPMC content, due to a lack of purging by less viscous formulation compositions.


Asunto(s)
Composición de Medicamentos/métodos , Liberación de Fármacos , Tecnología de Extrusión de Fusión en Caliente , Derivados de la Hipromelosa/química , Metilmetacrilatos/química , Nimodipina/química
5.
Int J Pharm ; 553(1-2): 408-421, 2018 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-30326284

RESUMEN

This work evaluates several compositions of an amorphous solid dispersion (ASD) comprising nimodipine (NMD) as poorly soluble model API in a dual-polymer carrier system. HPMC E5 and Eudragit E were used for the two polymeric carriers. The formulation was designed for hot-melt extrusion (HME) and subsequent strand pelletization. The aim was to identify a formulation window with desired functional ASD performance, i.e. physical stability and immediate API release, as well as processability in strand pelletization. Samples were prepared using small-scale methods, such as vacuum compression molding (VCM) and benchtop extrusion. Miscibility and phase studies were performed for a wide range of polymer ratios and three levels of API content (10-30% w/w). Ternary ASD formulations were phase-separated, yet physically stable upon exposure to elevated temperature/humidity. A study of phase composition showed that the drug molecules were predominantly solubilized in the Eudragit E fraction of the formulation. The miscibility study and Fourier-transform infrared spectroscopy indicated hydrogen (H)bond interactions between NMD and Eudragit E. In HPMC, the amorphous API was dispersed in polymeric matrix and stabilized due to anti-plasticization and the disruption of intermolecular Hbonding between API molecules. Concerning processability in strand pelletization the formulation is limited at high Eudragit E content. NMD and EE-rich phases exhibit low mixture glass transition, low melt stability and brittle breaking behavior upon strand cutting. The high viscosity and yield point of HPMC contributes to the mechanical robustness of the strand at temperatures relevant for processing. Formulation-intrinsic dissolution rates in VCM ASDs developed as an irregular function of polymer ratio, associated with diverse and competitive dissolution mechanisms in the polymers. With regard to the binary system of NMD with HPMC E5, surface crystallization was observed in VCM ASDs. For extruded pellets this was not the case, and a steady trend of formulation-intrinsic dissolution rate across different polymer ratios was observed. These discrepancies indicated a major influence of shear stress during sample preparation on HPMC-based ASD performance. Finally, a feasible formulation window within a polymer ratio of 1:2-2:3 Eudragit E:HPMC was identified in which Eudragit E acts as a dissolution rate enhancer and ASD stabilizer during dissolution.


Asunto(s)
Química Farmacéutica/métodos , Portadores de Fármacos/química , Nimodipina/administración & dosificación , Polímeros/química , Cristalización , Composición de Medicamentos/métodos , Liberación de Fármacos , Estabilidad de Medicamentos , Excipientes/química , Calor , Humedad , Enlace de Hidrógeno , Derivados de la Hipromelosa/química , Nimodipina/química , Ácidos Polimetacrílicos/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
6.
Eur J Pharm Sci ; 104: 72-81, 2017 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-28365300

RESUMEN

Tablet coating is a common unit operation in the pharmaceutical industry. To improve currently established processes, it is important to understand the influence of the process parameters on the coating quality. One of the critical parameters is the tablet velocity. In this work, numerical results are compared to results obtained experimentally. Tablet movement in the drums was simulated using the Discrete Element Method (DEM). The simulation parameters were adapted to fit the simulation to the experimental data. A comparison of the experimental and simulation results showed that the simulation correctly represents the real tablet velocity. A change in the velocity over time and its dependence on the rotation rates and the baffle position in the simulation were similar to the experimental results. In summary, simulations can improve the understanding of tablet coating processes and will thus provide insights into the underlying process mechanics, which cannot be obtained via ordinary experiments.


Asunto(s)
Química Farmacéutica , Comprimidos , Composición de Medicamentos
7.
Eur J Pharm Sci ; 93: 74-83, 2016 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-27516146

RESUMEN

Spray coating of tablets is an important unit operation in the pharmaceutical industry and is mainly used for modified release, enteric protection, better appearance and brand recognition. It can also be used to apply an additional active pharmaceutical ingredient to the tablet core. Scale-up of such a process is an important step in commercialization. However, scale-up is not trivial and frequently, at manufacturing scales the required coating quality cannot be reached. Thus, we propose a method where laboratory experiments are carried out, yet scale-up is done via computational methods, i.e., by extrapolating results to larger scales. In the recent years, the Discrete Element Method (DEM) has widely been used to simulate tablet behavior in a laboratory scale drum coater. Due the increasing computational power and more sophisticated DEM algorithms, it has become possible to simulate millions of particles on regular PCs and model industrial scale tablet coating devices. In this work, simulations were performed on the laboratory, pilot and industrial scales and DEM was used to study how different scale-up rules influence the bed behavior on larger scales. The material parameters of the tablets were measured in the laboratory and a glued sphere approach was applied to model the tablet shape. The results include a vast amount of qualitative and quantitative data at the different scales. In conclusion, the evolution of the inter-tablet coating variation for the different scales and process parameters is presented. The results suggest that keeping the Froude number constant during the scale up process leads to faster processes as the cycle time is shorter and the spray residence time is more uniform when compared to keeping the circumferential velocity constant.


Asunto(s)
Comprimidos , Composición de Medicamentos
8.
Bioresour Technol ; 200: 905-13, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26609947

RESUMEN

Experiments with a process development unit for fast pyrolysis of biomass residues of 10kgh(-1) have been performed to quantify the impact of two different product recovery options. Wheat straw, miscanthus and scrap wood have been used as feedstock. A separate recovery of char increases the organic oil yield as compared to a combined recovery of char and organic condensate (OC). Furthermore, it allows for an alternative use of the byproduct char which represents an important product fraction for the high ash biomass residues under consideration. The char produced shows little advantage over its biomass precursor when considered as energy carrier due to its high ash content. Significant value can be added by demineralizing and activating the char. The potential to increase the economic feasibility of fast pyrolysis is shown by an assessment of the bioliq® process chain.


Asunto(s)
Biomasa , Biotecnología/métodos , Carbón Orgánico/química , Temperatura , Carbono/análisis , Simulación por Computador , Triticum/química , Residuos , Madera/química
9.
Eur J Pharm Sci ; 90: 14-24, 2016 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-26709079

RESUMEN

This work concerns a tablet coating process in an industrial-scale drum coater. We set up a full-scale Design of Simulation Experiment (DoSE) using the Discrete Element Method (DEM) to investigate the influence of various process parameters (the spray rate, the number of nozzles, the rotation rate and the drum load) on the coefficient of inter-tablet coating variation (cv,inter). The coater was filled with up to 290kg of material, which is equivalent to 1,028,369 tablets. To mimic the tablet shape, the glued sphere approach was followed, and each modeled tablet consisted of eight spheres. We simulated the process via the eXtended Particle System (XPS), proving that it is possible to accurately simulate the tablet coating process on the industrial scale. The process time required to reach a uniform tablet coating was extrapolated based on the simulated data and was in good agreement with experimental results. The results are provided at various levels of details, from thorough investigation of the influence that the process parameters have on the cv,inter and the amount of tablets that visit the spray zone during the simulated 90s to the velocity in the spray zone and the spray and bed cycle time. It was found that increasing the number of nozzles and decreasing the spray rate had the highest influence on the cv,inter. Although increasing the drum load and the rotation rate increased the tablet velocity, it did not have a relevant influence on the cv,inter and the process time.


Asunto(s)
Industria Farmacéutica/instrumentación , Industria Farmacéutica/métodos , Modelos Teóricos , Comprimidos/química , Tecnología Farmacéutica/instrumentación , Tecnología Farmacéutica/métodos , Algoritmos , Composición de Medicamentos/instrumentación , Composición de Medicamentos/métodos
10.
Nervenarzt ; 86(8): 1007-17, 2015 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-26220007

RESUMEN

BACKGROUND: The provision of assistive devices (PAD) is a key element of care in amyotrophic lateral sclerosis (ALS). Since 2011, assistive devices (AD) have been coordinated in an internet-supported care network at university-based ALS centers in Berlin, Bochum, Hannover and Jena. The digitization of PAD processes has facilitated the evaluation of real-life ALS care. OBJECTIVES: Orthotics (OT), augmentative and alternative communication (AAC), supported treadmill (ST) and powered wheelchair (PW) were the PAD groups analyzed for delivery rates (proportion of delivered AD vs. medically indicated AD), rejection by patients and payers and latency of provision of care. RESULTS: Between June 2011 and October 2014 a total of 1479 patients and 12,478 AD were coordinated, among which 3313 PAD were related to OT, AAC, ST or EM. The median delivery rate was 64.3 %. The mean rejection rate by patients was 9.8 % (OT 5.4 %, AAC 9.8 %, ST 10.2 % and PW 15.6 %). Marked differences were noted in the rejection rate by payers and in care provision latency: OT (16.2 %, 68 days, n = 734), AAC (30.4 %, 96 days, n = 392), ST (34.8 %, 113 days, n = 164) and PW (35.6 %, 129 days, n = 259). Analysis of rejection rates showed significant differences among insurers. CONCLUSION: Only two thirds of the medically indicated AD reached the patients. Rejection rates by patients and payers and latency of provision of care were high. The PAD can substantially vary among health insurance companies. The establishment of consented criteria for PAD and their integration into treatment regimens and guidelines are crucial tasks for the future.


Asunto(s)
Esclerosis Amiotrófica Lateral/rehabilitación , Manejo de Caso/estadística & datos numéricos , Internet/estadística & datos numéricos , Aceptación de la Atención de Salud/estadística & datos numéricos , Dispositivos de Autoayuda/provisión & distribución , Dispositivos de Autoayuda/estadística & datos numéricos , Esclerosis Amiotrófica Lateral/epidemiología , Alemania/epidemiología , Asignación de Recursos para la Atención de Salud/estadística & datos numéricos , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Humanos , Internet/provisión & distribución , Estudios Longitudinales , Prevalencia , Revisión de Utilización de Recursos
11.
J Pharm Biomed Anal ; 78-79: 57-64, 2013 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-23454678

RESUMEN

Incorporation of an active pharmaceutical ingredient (API) into the coating layer of film-coated tablets is a method mainly used to formulate fixed-dose combinations. Uniform and precise spray-coating of an API represents a substantial challenge, which could be overcome by applying Raman spectroscopy as process analytical tool. In pharmaceutical industry, Raman spectroscopy is still mainly used as a bench top laboratory analytical method and usually not implemented in the production process. Concerning the application in the production process, a lot of scientific approaches stop at the level of feasibility studies and do not manage the step to production scale and process applications. The present work puts the scale up of an active coating process into focus, which is a step of highest importance during the pharmaceutical development. Active coating experiments were performed at lab and production scale. Using partial least squares (PLS), a multivariate model was constructed by correlating in-line measured Raman spectral data with the coated amount of API. By transferring this model, being implemented for a lab scale process, to a production scale process, the robustness of this analytical method and thus its applicability as a Process Analytical Technology (PAT) tool for the correct endpoint determination in pharmaceutical manufacturing could be shown. Finally, this method was validated according to the European Medicine Agency (EMA) guideline with respect to the special requirements of the applied in-line model development strategy.


Asunto(s)
Química Farmacéutica , Calibración , Modelos Teóricos , Reproducibilidad de los Resultados , Espectrometría Raman , Comprimidos
12.
Int J Pharm ; 439(1-2): 289-95, 2012 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22989986

RESUMEN

Terahertz pulsed imaging (TPI) is a recent and nondestructive technique to quantify coating thickness of pharmaceutical tablet film coatings. In this study, TPI is used for the first time to quantify the progress of an active coating process. The dosage form consisted of a push-pull osmotic system comprising a two-layer tablet core with a functional film coating and a laser drilled hole. On top of this system an active coating was applied. The coating thickness data acquired by TPI and optical microscopy was compared to the quantification of the active pharmaceutical ingredient (API) via HPLC. Good correlation of TPI and HPLC data was shown for coating thicknesses up to 500 µm. Due to the special structure of the dosage form, the TPI detection limit of 38 µm layer thickness was circumvented by analysing the coating thickness of active coating and functional subcoat in one. Therefore it was possible to monitor the active coating process from the very beginning of the process. Optical microscopy was no suitable reference technique for TPI thickness measurements. The active coating showed deformation artefacts during sample preparation, which biased the subsequent thickness measurements.


Asunto(s)
Composición de Medicamentos , Comprimidos/química , Cromatografía Líquida de Alta Presión , Microscopía , Control de Calidad , Propiedades de Superficie , Imágen por Terahertz
14.
Transfus Med ; 20(1): 38-47, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19708895

RESUMEN

Among the family of herpes viruses, only cytomegalovirus (CMV) and, to a lesser extent, human herpes virus 8 (HHV-8) are of relevance in transfusion medicine. Due to neutropism, herpes simplex viruses (HSV) types 1 and 2 are considered to be of minor relevance. However, several reports gave evidence that a HSV DNAemia might occur and HSV could therefore be transmissible by blood products. The aim of our study was to collect data about prevalence of HSV antibodies among blood donors and to clarify whether HSV DNAemia is possible. HSV antibody states of 653 blood donors were investigated. Blood specimens of 46 patients with primary and recurrent HSV infection were tested for HSV-1 and HSV-2 DNA using TaqMan polymerase chain reaction. In 505 of the 653 blood donors HSV antibodies were detectable, most of which were HSV-1 antibodies. HSV DNA was detected in plasma, but not in peripheral blood mononuclear cells (PBMCs) of seven rather seriously ill patients with primary herpes genitalis. No HSV viraemia was detectable in otherwise healthy patients with recurrent herpes labialis. Thus, HSV DNAemia is possible, but seems to be limited to primary infections and could not be detected in the recurrent infection. Therefore, blood donors with primary herpes infection should be deferred from donation. Blood donors with recurrent HSV infection are probably not at risk of transmitting HSV, but further studies are necessary to prove this hypothesis. Detection of HSV DNA in PBMCs as described formerly could not be confirmed by this study.


Asunto(s)
Donantes de Sangre , Transfusión Sanguínea/normas , ADN Viral/sangre , Selección de Donante/normas , Herpes Simple/virología , Herpesvirus Humano 1/aislamiento & purificación , Herpesvirus Humano 2/aislamiento & purificación , Plasma/virología , Viremia/virología , Adolescente , Adulto , Anciano , Anticuerpos Antivirales/sangre , Femenino , Alemania/epidemiología , Herpes Genital/sangre , Herpes Genital/epidemiología , Herpes Genital/virología , Herpes Labial/sangre , Herpes Labial/epidemiología , Herpes Labial/virología , Herpes Simple/sangre , Herpes Simple/epidemiología , Herpes Simple/prevención & control , Herpes Simple/transmisión , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/inmunología , Herpesvirus Humano 2/genética , Herpesvirus Humano 2/inmunología , Humanos , Leucocitos/virología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Prevalencia , Recurrencia , Sensibilidad y Especificidad , Estudios Seroepidemiológicos , Reacción a la Transfusión , Viremia/epidemiología , Adulto Joven
15.
Rev. chil. cir ; 61(2): 168-170, abr. 2009. ilus
Artículo en Español | LILACS | ID: lil-538020

RESUMEN

Primary malignant melanoma of the esophagus is an extremely rare tumor. Less than 300 cases have been published worldwide. Although surgical excision is the best possible therapeutic option, the prognosis is poor. We report a 70 years old man, who underwent an esophagoscopy due to a 6-months history of dysphagia and upper abdominal discomfort. There was no history of previous cutaneous melanoma. A polypoid and pigmented mass (of 5 cm diameter) almost completely occluding the lumen in the lower third of the esophagus, was found. The histological diagnosis of the initial biopsy was melanoma. Transhiatal esophagectomy was performed and the esophagus was replaced by an isoperistaltic gastric tube with cervical esophageal anastomosis. The excised specimen showed a polypoid tumor with black pigmentation of 5.5 cm. The diagnosis of pathological and immunohistochemical studies was a primary esophageal malignant melanoma. The resection margins of esophagus were free of tumor. He received no postoperative adjuvant therapy and signs of recurrence were observed 3 months after the operation.


El melanoma primario maligno del esófago es extremadamente raro y menos de 300 casos han sido publicados hasta el momento. Aunque la resección quirúrgica ha sido considerada como la mejor opción, el pronóstico es muy pobre. Se presenta a un paciente de 70 años a quien se le realizó una esofagogastroscopía por disfagia y epigastralgia de 6 meses de evolución. No había antecedentes de melanoma cutáneo. El examen demostró una masa polipoidea pigmentada de 5 cm de diámetro en el tercio inferior del esófago, que la biopsia informó como melanoma maligno. Se realizó una esofagectomía transhiatal y el estómago fue reemplazado por un tubo gástrico isoperistáltico con una anastomosis esofagogástrica cervical. El estudio de la pieza operatorio demostró un tumor polipoideo de 5,5 cm, con pigmentación negra. El estudio histológico demostró que el tumor correspondía a un melanoma maligno primario del esófago. Los márgenes de resección oral y caudal estaban libres de tumor. No recibió terapia adyuvante complementaria y a los 3 meses de la intervención había signos clínicos e imagenológicos de recurrencia de la enfermedad.


Asunto(s)
Humanos , Masculino , Anciano , Esofagectomía , Melanoma/cirugía , Neoplasias Esofágicas/cirugía , Resultado Fatal , Melanoma/patología , Neoplasias Esofágicas/patología , Recurrencia
16.
Rev. chil. cir ; 58(4): 293-297, ago. 2006. tab
Artículo en Español | LILACS | ID: lil-475802

RESUMEN

En el caso de pacientes con cáncer gástrico T4, puede estar indicada la quimiorradioterapia si no es posible la resección de las estructuras infiltradas. Analizamos 10 pacientes con cáncer gástrico irresecable (8 hombres, 2 mujeres) tratados por nosotros en el periodo 2003-2005. Después de la laparotomía exploradora, los pacientes con cáncer gástrico localmente avanzados e irresecables son tratados con RT-QT concomitante 2 semanas después de la laparotomía. El tratamiento consistió en radioterapia a dosis de 45 Gy en 25 fracciones de 1.8 Gy, 5 veces por semana por 5 semanas sobre estómago y linfáticosregionales, y 5 FU en 1ª y 5º semana (425mg/m2) o Capecitabina 825 mg/m2 diarios, en dos dosis, cada12 hrs. Un mes después se realiza la segunda laparotomía con resección del estómago y linfadenectomía en casos de remisión total o parcial de la enfermedad. Todos los carcinomas fueron proximales. Nueve pacientes se reintervinieron, un paciente tuvo progresión de la enfermedad. Un paciente fue nuevamente irresecable y ocho fueron sometidos a una gastrectomía total D2. Se logró respuesta patológica completa en tres casos (no había cáncer residual en el estómago ni en los ganglios) y parcial en cinco. Creemos que en cáncer gástrico T4 localmente irresecable la RT-QT seguida de cirugía es una buena alternativa terapéutica.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Adenocarcinoma , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/radioterapia , Antimetabolitos Antineoplásicos/uso terapéutico , Quimioterapia Adyuvante , Terapia Combinada , Desoxicitidina/uso terapéutico , Fluorouracilo/uso terapéutico , Invasividad Neoplásica/prevención & control , Metástasis de la Neoplasia/prevención & control , Estadificación de Neoplasias , Neoplasias Gástricas/cirugía , Radioterapia Adyuvante , Resultado del Tratamiento
17.
Ann Rheum Dis ; 63(12): 1645-8, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15547089

RESUMEN

OBJECTIVE: To investigate whether variation in the HLA-DM gene is important in producing a group of pathogenic autoantibodies-antiphospholipid antibodies (aPL)-on the basis that HLA class II restricted antigen presentation is involved in the production of aPL. METHODS: HLA-DMA and DMB polymorphisms were genotyped by polymerase chain reaction combined with restriction enzyme digestion in 51 white patients with primary antiphospholipid syndrome (APS), 82 with systemic lupus erythematosus (SLE) (42 with APS and 40 without APS), and 109 healthy white controls. The association with the aPL profile was examined. RESULTS: The distribution of DMA alleles in APS patients and in patients with APS associated with SLE was significantly different from that in controls by 4x2 chi(2) test with 3 degrees of freedom (p = 0.035 and 0.011, respectively), but it was not different between SLE patients without APS and controls. The allelic distribution of DMA was also different between patients with IgG class anticardiolipin antibody or those with lupus anticoagulant (LA) and controls (p = 0.012 and 0.007, respectively) and between patients with and without LA among SLE patients (p = 0.035). All these differences included the increase in DMA*0102 in the former groups. CONCLUSIONS: The results suggest that HLA-DMA*0102 or its linked gene(s) form one of the genetic risks for the production of aPL.


Asunto(s)
Anticuerpos Antifosfolípidos/biosíntesis , Síndrome Antifosfolípido/genética , Antígenos HLA-D/genética , Polimorfismo Genético , Adulto , Anciano , Síndrome Antifosfolípido/etiología , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Prueba de Histocompatibilidad , Humanos , Lupus Eritematoso Sistémico/complicaciones , Masculino , Persona de Mediana Edad
18.
Rev. chil. cir ; 56(5): 443-448, oct. 2004. tab, graf
Artículo en Español | LILACS | ID: lil-394628

RESUMEN

Introducción: En los últimos años se han producido un aumento de la población anciana que debe ser sometida a gastrectomía pos cáncer gástrico. Algunos autores consideran a la edad como un factor de riesgo importante de morbimortalidad en cirugía. Otros consideran que son las patología concomitantes y no la edad las que aumentan el riesgo. Material y Métodos: Estudio retrospectivos de los pacientes portadores de cáncer gástrico sometidos a gastrectomía total en el Hospital Clínico Regional de Concepción entre los años 1985 y 1999. Se dividen en grupo I, menores de 65 años. Resultados: Se estudian 263 pacientes, 162 menores de 65 años. La distribución por sexo fue similar (73,3 por ciento en grupo II). Los pacientes ancianos presentaron un 36,9 por ciento de patología concominate y los jóvenes un 14,8 por ciento (p< 0,000086). Las características de los tumores (localización, grado de diferenciación y profundidad de invasión) fueron similares en los grupos. En los ancianos predominó el tipo intestinal de Lauren (58,6 por ciento) y en los jóvenes el tipo difuso (56,1 por ciento) (p< 0,03). Los jóvenes fueron etapificados principalmente en el grupo III (67,3 por ciento), los ancianos se distribuyeron en las etapas II (22,8 por ciento), IIIA (28,7 por ciento) y IV (23,7 por ciento) (p<0,0005). La mortalidad fue de 24,1 por ciento en el grupo I y 37,6 por ciento en el grupo II (ns), y predominaron las complicaciones respiratorias. La mortalidad fue de 2,5 por ciento en el grupo I y 6,9 por ciento en el grupo II (ns). La estadía hospitalaria fue similar en ambos grupos. Conclusiones: Un 38,2 por ciento de los pacientes con cáncer gástrico sometidos a gastrectomía total son mayores de 65 años. Los ancianos presentan un mayor número de patologías asociadas que los jóvenes. Las características de los tumores son similares en ancianos y jóvenes. No existe relación entre la edad y la etapa del tumor. La morbilidad, mortalidad operatoria y estadía hospitalaria no mostraron diferencias significativas.


Asunto(s)
Humanos , Masculino , Femenino , Anciano , Gastrectomía/mortalidad , Neoplasias Gástricas , Chile , Factores de Riesgo
19.
Rev. chil. cir ; 56(3): 226-231, jun. 2004. ilus, tab
Artículo en Español | LILACS | ID: lil-394593

RESUMEN

Introducción: Las complicaciones postoperatorias habituales de la gastrectomía total son la dehiscencia de la anastomosis esófago-yeyunal y los abscesos subfrénicos. Estas complicaciones son causa de morbimortalidad, reintervenciones y de períodos postoperatorios prolongados. Los drenes abdominales serían útiles en el diagnóstico precoz de la fístula de la anastomosis y el tratamiento. Objetivo: Analizar nuestra experiencia en gastrectomía total por cáncer gástrico en pacientes con y sin drenes abdominales y evaluar los resultados en la morbilidad operatoria, período de hospitalización postoperatoria, tiempo de realimentación oral, número de reintervenciones y morbilidad operatoria. Material y Método: Se realiza un estudio prospectivo y randomizado en 60 pacientes (43 hombres y 17 mujeres) sometidos a una gastrectomía total por cáncer gástrico en el Hospital Clínico Regional de Concepción en el período 2000-2003. Los pacientes se dividieron en 2 grupos: Grupo I (sin drenes) y Grupo II (2 drenes). Resultados: El Grupo I fue de 31 pacientes y el Grupo II de 29 pacientes. El período de hospitalización postoperatoria fue de un promedio de 12,9 días en el Grupo I y de 18,8 días en el Grupo II (p= 0,0242, s.). La morbilidad fue de 97 por ciento en el Grupo I y de 37,9 por ciento en el Grupo II (0,0242, s.). Las reintervenciones fueron más frecuentes en el Grupo II (24,1 por ciento) que en el Grupo I (9,7 por ciento)(p= 0,1239), n.s.). La realimentación oral se inició a los 9,4 días promedio en el Grupo I y a los 12,8 días en el Grupo II (p= 0,0514, n.s.). La mortalidad operatoria fue de 0 por ciento en el Grupo I y de 3,4 por ciento en el Grupo II (p= 0,4833, n.s.). Conclusión: En nuestra experiencia la morbilidad operatoria y el tiempo de hospitalización postoperatoria son significativamente mayores en el grupo de pacientes con drenes abdominales.


Asunto(s)
Humanos , Masculino , Femenino , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/mortalidad , Drenaje/efectos adversos , Fístula Gástrica , Gastrectomía/mortalidad , Neoplasias Gástricas , Anastomosis Quirúrgica , Morbilidad , Estudios Prospectivos
20.
J Clin Microbiol ; 41(6): 2763-7, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12791926

RESUMEN

Human papillomavirus (HPV) DNA loads of six oncogenic HPV types were measured by real-time PCR in cervical scrapes of human immunodeficiency virus (HIV)-infected and uninfected women. In both groups, HPV loads increased with the grade of cervical disease. HIV infection did not affect HPV loads in low-grade lesions but was associated with significantly higher HPV loads in severe dysplasia; highest loads were found in advanced HIV disease. Our data reflect the aggressive course of HPV infection in HIV-positive women.


Asunto(s)
ADN Viral/análisis , Infecciones por VIH/complicaciones , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/virología , Enfermedades del Cuello del Útero/virología , Neoplasias del Cuello Uterino/virología , Adolescente , Adulto , Anciano , Progresión de la Enfermedad , Femenino , Infecciones por VIH/virología , Humanos , Persona de Mediana Edad , Papillomaviridae/clasificación , Papillomaviridae/genética , Reacción en Cadena de la Polimerasa , Enfermedades del Cuello del Útero/fisiopatología , Neoplasias del Cuello Uterino/fisiopatología
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