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1.
J Control Release ; 324: 280-288, 2020 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-32439360

RESUMEN

Multiple vaccines can be mixed into a single combination to be a single product. However, combination vaccines have problems of complexity. In this study, microneedles were utilized in a compartmental microneedle array (CMA) to deliver two influenza vaccine strains without mixing. In this study, the CMA had two compartments, and two rectangular structures were attached to each end of the array to enable integration of the compartments with the coating equipment. The coating solution, which contained influenza vaccines for B/Yamagata (B-Y) and B/Victoria (B-V), was filled into the two reservoirs of the container. The CMA was aligned with the container for dipping the first compartment of the array into the first reservoir and the second compartment into the second reservoir. The CMA containing B-Y and B-V separately was administered to mice, and weight change and survival were compared with other groups of mice administered (a) combination vaccines with microneedles, (b) two monovalent vaccines with microneedles, (c) intramuscularly with a combination vaccine, and (d) intramuscularly with two monovalent vaccines. Plaque reduction neutralization tests were also performed to compare the CMA group with the other groups. The CMA showed a relative standard error of less than 7% between samples in dose uniformity. It also showed comparable antibody-forming efficacy compared to other groups, especially by B/Yamagata virus challenge. The CMA mice group showed better survival and weight change than mice that received intramuscular (IM) injection of the combination vaccine. In the neutralizing antibody experiment, all microneedle groups showed a higher neutralizing antibody than the IM groups. Vaccines were administered without mixing by a single administration using a CMA, and the CMA showed comparable efficacy with IM administration of the combination vaccine. Multivalent vaccines can be delivered without mixing as a single product by using a CMA.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Vacunas contra la Influenza , Gripe Humana , Animales , Anticuerpos Antivirales , Ratones , Agujas , Vacunación , Vacunas Combinadas
2.
Drug Deliv Transl Res ; 10(3): 791-800, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31974729

RESUMEN

The dissolution rate of a microneedle array patch (MAP) determines how long a MAP must remain attached to the skin (often called "wear time"). In this study, the dissolution rate of a MAP was increased, not by changing the drug formulation but by employing an infrared (IR) device that is widely used for hospital treatment and in-home therapy. A MAP with microneedles 480 µm in height was prepared using hyaluronic acid (HA). Changes in transepidermal water loss (TEWL), the surface temperature of the skin, and the dissolution rate of the MAP tips with IR irradiation were evaluated on human skin in vivo. Time for recovery from erythema that occurred after MAP attachment and IR irradiation was also evaluated. TEWL increased more than fourfold with IR irradiation. Water that evaporated as a result of IR irradiation was trapped in the skin layer by the patch, resulting in the increased dissolution rate of the MAP tips. After 10 min of IR irradiation, the height of the dissolving tips compared with their initial height increased from 41 to 56%, and the dissolved volume of the tips compared with their initial volume increased from 7 to 18%. During the 10 min of irradiation, the skin surface temperature rose from 32 to 40 °C. Erythema occurred in the early stage of treatment with IR irradiation and MAP attachment, but it abated within 2 h after removal of the MAP and cessation of IR irradiation. Through this study, it was possible to shorten the administration time of MAPs by using an IR device that could be easily accessed. This method can be applied to various types of MAPs in order to reduce the time that the MAPs must remain attached to the skin without changing the drug formulation. Graphical abstract The increase in dissolution rate of dissolving microneedle array patch (MAP) as a result of infrared radiation. a Water-soluble tips of MAP dissolved in water in skin without infrared irradiation. Dotted line indicates the initial dissolving microneedles. b Water in skin and subcutaneous layer evaporated actively with infrared irradiation and was stored under patch of MAP. Increased amount of water in skin induced faster dissolution of MAP tips.


Asunto(s)
Eritema/etiología , Ácido Hialurónico/administración & dosificación , Rayos Infrarrojos/efectos adversos , Adulto , Femenino , Humanos , Ácido Hialurónico/química , Masculino , Microinyecciones/instrumentación , Solubilidad , Parche Transdérmico
3.
Eur J Pharm Biopharm ; 143: 1-7, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31398438

RESUMEN

During the manufacture of H1N1 microneedles, a stabilizer is usually added to maintain the antigenicity of the vaccine. However, finding a suitable stabilizer is difficult, and the addition of a stabilizer can limit the antigen dose and the addition of an adjuvant because of the limited volume of the microneedles. In this study, the authors evaluated whether H1N1 microneedles could be fabricated without a stabilizer by keeping the production environment at a low temperature. H1N1 microneedle patches without a stabilizer were prepared in a process that involved maintaining a low temperature of 10 °C. The protective immune response to this method of drug application was investigated by comparing it with traditional intramuscular (IM) immunization and with the use of H1N1 microneedles with a stabilizer. A process-sensitive antigen, H1N1, was stabilized without the use of a stabilizer in a process that maintained a low temperature of 10 °C. The preparation process consisted of coating and drying processes. In animal experiments, mice were immunized using an array of low-temperature H1N1 microneedles without a stabilizer (LT-MN), and they showed strong antibody responses. Compared to three other application methods of traditional IM immunization, low-temperature H1N1 microneedles with a stabilizer (LT-MN-T), and room-temperature H1N1 microneedles with a stabilizer (RT-MN-T), LT-MN produced comparable results in inducing protective immunity. A plaque reduction neutralization test found that LT-MN and LT-MN-T provided greater immunity compared with IM and RT-MN-T. A process in which the temperature is maintained at 10 °C can provide successful vaccination with H1N1 microneedles without the addition of a stabilizer. This process can be applied to various temperature-sensitive biologics.


Asunto(s)
Excipientes/química , Subtipo H1N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/química , Animales , Anticuerpos Antivirales/inmunología , Formación de Anticuerpos/inmunología , Femenino , Inmunización/métodos , Vacunas contra la Influenza/inmunología , Inyecciones Intradérmicas/métodos , Ratones , Ratones Endogámicos BALB C , Agujas , Pruebas de Neutralización/métodos , Temperatura , Vacunación/métodos
4.
Proc Natl Acad Sci U S A ; 116(36): 18060-18067, 2019 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-31427534

RESUMEN

Translational control plays a key role in regulation of neuronal activity and behavior. Deletion of the translational repressor 4E-BP2 in mice alters excitatory and inhibitory synaptic functions, engendering autistic-like behaviors. The contribution of 4E-BP2-dependent translational control in excitatory and inhibitory neurons and astrocytic cells to these behaviors remains unknown. To investigate this, we generated cell-type-specific conditional 4E-BP2 knockout mice and tested them for the salient features of autism, including repetitive stereotyped behaviors (self-grooming and marble burying), sociability (3-chamber social and direct social interaction tests), and communication (ultrasonic vocalizations in pups). We found that deletion of 4E-BP2 in GABAergic inhibitory neurons, defined by Gad2, resulted in impairments in social interaction and vocal communication. In contrast, deletion of 4E-BP2 in forebrain glutamatergic excitatory neurons, defined by Camk2a, or in astrocytes, defined by Gfap, failed to cause autistic-like behavioral abnormalities. Taken together, we provide evidence for an inhibitory-cell-specific role of 4E-BP2 in engendering autism-related behaviors.


Asunto(s)
Trastorno Autístico/metabolismo , Conducta Animal , Factores Eucarióticos de Iniciación/deficiencia , Neuronas GABAérgicas/metabolismo , Interneuronas/metabolismo , Biosíntesis de Proteínas , Animales , Astrocitos/metabolismo , Astrocitos/patología , Trastorno Autístico/genética , Trastorno Autístico/patología , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Neuronas GABAérgicas/patología , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Glutamato Descarboxilasa/genética , Glutamato Descarboxilasa/metabolismo , Interneuronas/patología , Ratones , Ratones Noqueados
5.
IUCrJ ; 6(Pt 4): 681-687, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31316811

RESUMEN

The structural dimension of metal-organic frameworks (MOFs) is of great importance in defining their properties and thus applications. In particular, 2D layered MOFs are of considerable interest because of their useful applications, which are facilitated by unique structural features of 2D materials, such as a large number of open active sites and high surface areas. Herein, this work demonstrates a methodology for the selective synthesis of a 2D layered MOF in the presence of the competitive formation of a 3D MOF. The ratio of the reactants, metal ions and organic building blocks used during the reaction is found to be critical for the selective formation of a 2D MOF, and is associated with its chemical composition. In addition, the well defined and uniform micro-sized 2D MOF particles are successfully synthesized in the presence of an ultrasonic dispersion. Moreover, the laminated 2D MOF layers are directly synthesized via a modified bottom-up lamination method, a combination of chemical and physical stimuli, in the presence of surfactant and ultrasonication.

6.
Inorg Chem ; 57(15): 9048-9054, 2018 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-30044605

RESUMEN

Porous metal-organic frameworks (MOFs) are interesting materials owing to their interesting structural features and their many useful properties and applications. In particular, the structural features are greatly important to optimize the MOFs' porosities and so properties. Indeed, the MOFs' well-developed micropore and high surface area are the most important structural features, and as such, many practical applications of MOFs originate from these structural features. We herein demonstrate a strategy for improving the crystallinity of MOFs, and so increasing the porosity and surface area of poorly crystalline MOFs by making them in core-shell-type hybrids through the induced growth on the well-crystalline template. Although poorly crystalline versions of MOFs generate naturally in the absence of the well-crystalline template, well-crystalline versions of MOFs produce inductively in the presence of the well-crystalline template. In addition, the crystallinity enhancement of MOFs brings together the improvement in their porosities and surface areas. The surface areas and pore volumes of the well-crystalline versions of MOFs produced through the induced growth on the template are calculated based on this study, indicating that MOF surface areas increase by up to 7 times compared to the poorly crystalline versions.

7.
Nanoscale ; 9(35): 12850-12854, 2017 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-28849833

RESUMEN

The conjugation of metal-organic frameworks (MOFs) with other materials is an excellent strategy for the production of advanced materials having desired properties and so appropriate applicability. In particular, the integration of MOFs with a flexible paper is expected to form valuable materials in separation technology. Here we report a simple method for the generation of MOF papers through the compact and uniform growth of MOF nanoparticles on the cellulose surface of a carboxymethylated filter paper. The resulting MOF papers show a selective capture ability for negatively charged organic dyes and they can be used for dye separation through simple filtration of a dye solution on the MOF papers. In addition, MOF papers can be reused after a simple washing process without losing their effective dye capture ability.

8.
Tissue Eng Regen Med ; 13(4): 437-445, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30603425

RESUMEN

Hydroxyapatite (HA) blocks as an alternative material for autogenous onlay bone grafts are regarded as an insufficient substitute for osseointegration of dental implant. In this study, we evaluated the effects of dog mesenchymal stromal cells (dMSCs) with or without bone morphogenetic protein-2 (BMP) on new peri-implant bone formation after HA block graft. In four mandibular bone defects (8×8×6 mm each) in five beagle dogs, dental implants were placed with HA block loaded with autogenous dMSCs with or without BMP-2. Animals were sacrificed at eight weeks, and bone healing was evaluated among four groups consisting of 1) HA alone as a control, 2) HA+dMSCs, 3) HA+BMP-2, and 4) HA+dMSCs+BMP-2. According to histomorphometric evaluation, the MSC+BMP-2 group and the BMP-2 group showed significantly higher bone-implant-contact (BIC) length than the MSC group, while there was no significant difference in new bone formation among the groups. According to micro-CT analysis, bone volume and bone mineral density were significantly higher in the MSC+BMP-2 group compared with the control group (p<0.01 and p<0.05, respectively). BIC was significantly higher in the MSC+BMP-2 group than both the control and MSC groups (p<0.01 and p<0.05, respectively). In conclusion, our results showed that bone regeneration at peri-implant bone defects grafted with HA blocks was significantly increased by dual delivery of MSCs and BMP-2. Conversely, HA blocks with MSC or BMP-2 alone did not allow for efficient peri-implant bone regeneration.

9.
Vaccine ; 32(17): 1954-63, 2014 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-24530145

RESUMEN

BACKGROUND: In low- and middle-income countries neonatal infections are important causes of infant mortality. Group B streptococcus (GBS) is a major pathogen. A GBS polysaccharide-protein conjugate vaccine, the only option that has the potential to prevent both early- and late-onset GBS disease, has completed Phase II trials. Screening-based intrapartum antibiotic prophylaxis (IAP) for pregnant women, an effective strategy in high-income countries, is often not practical in these settings. Risk factor-based IAP (RFB-IAP) for women with risk factors at delivery has had limited success in preventing neonatal infection. We evaluated the cost and health impacts of maternal GBS vaccination in South Africa. METHODS AND FINDINGS: We developed a decision-analytic model for an annual cohort of pregnant women that simulates the natural history of GBS disease in their infants. We compared four strategies: doing nothing, maternal GBS vaccination, RFB-IAP, and vaccination plus RFB-IAP. Assuming vaccine efficacy varies from 50% to 90% against covered serotypes and 75% of pregnant women are vaccinated, GBS vaccination alone prevents 30-54% of infant GBS cases compared to doing nothing. For vaccine prices between $10 and $30, and mid-range efficacy, its cost ranges from $676 to $2390 per disability-adjusted life-year (DALY) averted ($US 2010), compared to doing nothing. RFB-IAP alone, compared to doing nothing, prevents 10% of infant GBS cases at a cost of $240/DALY. Vaccine plus RFB-IAP prevents 48% of cases at a cost of $664-2128/DALY. CONCLUSIONS: Vaccination would substantially reduce the burden of infant GBS disease in South Africa and would be very cost-effective by WHO guidelines. RFB-IAP is also very cost-effective, but prevents only 10% of cases. Vaccination plus RFB-IAP is more effective and more costly than vaccination alone, and consistently very cost-effective.


Asunto(s)
Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Complicaciones Infecciosas del Embarazo/prevención & control , Infecciones Estreptocócicas/prevención & control , Vacunas Estreptocócicas/economía , Vacunación/economía , Profilaxis Antibiótica/economía , Análisis Costo-Beneficio , Femenino , Humanos , Transmisión Vertical de Enfermedad Infecciosa/economía , Modelos Económicos , Embarazo , Complicaciones Infecciosas del Embarazo/economía , Factores de Riesgo , Sudáfrica , Infecciones Estreptocócicas/economía , Vacunas Estreptocócicas/uso terapéutico , Streptococcus agalactiae
10.
Obstet Gynecol Sci ; 56(2): 121-5, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24327990

RESUMEN

Mature cystic teratomas of the ovary (MCT) are usually observed in women of reproductive age with the most dreadful complication being malignant transformation which occurs in approximately 1% to 3% of MCTs. In this case report, we present a patient with squamous cell carcinoma which developed from a MCT during pregnancy. The patient was treated conservatively without adjuvant chemotherapy and was followed without evidence of disease for more than 60 months using conventional tools as well as positron emission tomography-computed tomography following the initial surgery. We report this case along with the review of literature.

11.
Soft Matter ; 9(10): 2912-2919, 2013 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-33335560

RESUMEN

Thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) hydrogels are widely studied smart materials, particularly for biomedical applications, but are limited by their mechanical strength. In this study, double network (DN) hydrogels were prepared with an asymmetric crosslink design and inclusion of an electrostatic co-monomer, 2-acrylamido-2-methylpropane sulfonic acid (AMPS). These P(NIPAAm-co-AMPS)/PNIPAAm DN hydrogels were sequentially formed with a tightly crosslinked 1st network comprised of variable levels of AMPS (100 : 0 to 25 : 75 wt% ratio of NIPAAm:AMPS) and a loosely crosslinked 2nd network comprised of PNIPAAm. The impact of AMPS content in the 1st network on the volume phase transition temperature (VPTT), morphology, deswelling-reswelling kinetics and mechanical properties was evaluated. Without substantially altering the VPTT of conventional PNIPAAm hydrogels but with improving thermosensitivity, the DN hydrogel formed with 25 : 75 wt% of NIPAAm:AMPS achieved exceptional strength, high modulus and high %strain at break.

12.
Ann Epidemiol ; 22(8): 575-80, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22695390

RESUMEN

PURPOSE: To reanalyze results reported in 2008, using propensity score matching, to test the treatment effect of non-leisure physical activity on survival. METHODS: McCullagh's ordinal logit model was used to estimate propensity scores, separately for adults aged 35-59 and 60-74 years at baseline in the National Health and Nutrition Examination Survey I Epidemiologic Followup Study, for three levels of non-leisure activity. Each untreated adult (low non-leisure activity) was matched to two treated adults from the same age group, one with moderate and one with high non-leisure activity. Multivariable Cox proportional hazard regressions were fitted to the matched samples and compared with regressions fitted to unmatched samples. RESULTS: Except for moderate leisure-time activity and age, observed covariates were well balanced after matching. For adults aged 35-59 years, matched regressions showed smaller mortality reductions: 23% for moderate and 32% for high non-leisure activity, compared with low non-leisure activity. For adults aged 60-74 years, matched regressions showed a smaller mortality reduction for moderate non-leisure activity (29%) but a larger reduction for high non-leisure activity (47%). CONCLUSIONS: In line with published reviews of conventional multivariable analysis versus propensity score matching, Cox regressions on matched and unmatched samples produced similar estimates of treatment effects for non-leisure activity, but the estimates from matched regressions were usually smaller.


Asunto(s)
Actividades Cotidianas , Mortalidad/tendencias , Actividad Motora , Puntaje de Propensión , Adulto , Anciano , Causas de Muerte , Humanos , Estilo de Vida , Persona de Mediana Edad , Análisis Multivariante , Modelos de Riesgos Proporcionales , Análisis de Regresión , Análisis de Supervivencia
13.
Soft Matter ; 8(2): 481-487, 2012 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-23293658

RESUMEN

The utility and efficacy of thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) hydrogels as smart materials is limited by their physical properties. In this study, we sought to design PNIPAAm nanocomposite hydrogels which displayed enhanced mechanical properties as well as deswelling-reswelling kinetics but without reducing equilibrium swelling or altering the convenient volume phase transition temperature (VPTT) of PNIPAAm. PNIPAAm hydrogels were formed as double networks (DN) comprised of a tightly crosslinked 1st network and a loosely crosslinked 2nd network. In addition, polysiloxane nanoparticles of two different average diameters (~50 nm and ~200 nm) were incorporated during formation of the 1st or 2nd network. The influence of the hydrogel composition on VPTT, morphology, equilibrium swelling, deswelling-reswelling kinetics and mechanical properties was evaluated. We observed that DN hydrogels formed with ~200 nm polysiloxane nanoparticles introduced during formation of the 1st network achieved the best combination of the desired properties.

14.
Bioorg Med Chem Lett ; 20(22): 6858-60, 2010 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-20855209

RESUMEN

Novel hybrids of non acetal and acetal-type derivatives at C-12 of artemisinin and glycolipids were synthesized via efficient coupling reactions. Some of these hybrids showed potent in vivo antiangiogenic activity on the chorioallantoic membrane (CAM) that was higher than or comparable to those of fumagillin and thalidomide at a concentration of 2.5 nmol.


Asunto(s)
Inhibidores de la Angiogénesis/síntesis química , Inhibidores de la Angiogénesis/farmacología , Artemisininas/química , Corion/efectos de los fármacos , Glucolípidos/química , Animales , Embrión de Pollo
15.
J Korean Med Sci ; 17(2): 263-5, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11961315

RESUMEN

Stenotrophomonas maltophilia (previously named Xanthomonas maltophilia) is an aerobic, non-fermentive, Gram-negative bacillus that is wide spread in the environment. It was considered to be an organism with limited pathogenic potential, which was rarely capable of causing diseases in human other than those who were in debilitated or immunocompromised state. More recent studies have established that Stenotrophomonas maltophilia can behave as a true pathogen. Endocarditis due to this organism is rare, and only 24 cases of Stenotrophomonas maltophilia endocarditis have been reported in the medical literature. Most cases were associated with risk factors, including intravenous drug abuse, dental treatment, infected intravenous devices, and previous cardiac surgery. We present a case with two episodes of Stenotrophomonas maltophilia endocarditis after mitral valve prosthesis implantation, which was treated with antibiotics initially, and a combination of antibiotics and surgery later. To our knowledge, this is the first case of repetitive endocarditis due to Stenotrophomonas maltophilia.


Asunto(s)
Antibacterianos/uso terapéutico , Bioprótesis/microbiología , Endocarditis Bacteriana/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Prótesis Valvulares Cardíacas/microbiología , Stenotrophomonas maltophilia/efectos de los fármacos , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Adulto , Bioprótesis/efectos adversos , Endocarditis Bacteriana/fisiopatología , Gentamicinas/uso terapéutico , Infecciones por Bacterias Gramnegativas/fisiopatología , Prótesis Valvulares Cardíacas/efectos adversos , Humanos , Masculino , Válvula Mitral , Recurrencia , Resultado del Tratamiento , Vancomicina/uso terapéutico
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