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1.
Int J Pharm ; 661: 124398, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38964491

RESUMEN

Despite the continuous research on understanding how topical drugs and the skin interact, the development of a topical generic product remains a challenge. Due to their local action effect rather than systemic, establishing suitable frameworks for documenting bioequivalence between reference and test formulations is anything but straightforward. In previous years, clinical endpoint trials were considered the gold standard method to demonstrate bioequivalence between topical products. Nevertheless, significant financial and time resources were required to be allocated owing to the inherent complexity of these studies. To address this problem, regulatory authorities have begun to accept alternative approaches that could lead to a biowaiver, avoiding the need for clinical endpoint trials. These alternatives encompass various in vitro and/or in vivo techniques that have been analysed and the benefits and drawbacks of each method have been considered. Furthermore, other factors like the integration of a quality by design framework to ensure a comprehensive understanding of the product and process quality attributes have also been taken into account. This review delves into international regulatory recommendations for semisolid topical products, with a focus on those established by the European Medicines Agency, as well as the Food and Drug Administration. Both approaches were carefully examined, discussing aspects such as acceptance criteria, sample size, and microstructure evaluation. Additionally, novel and innovative therapeutic-driven approaches based on in vitro disease models for the rapid and effective development of topical generic products are presented.


Asunto(s)
Administración Tópica , Medicamentos Genéricos , Equivalencia Terapéutica , Medicamentos Genéricos/farmacocinética , Medicamentos Genéricos/administración & dosificación , Humanos , Animales , United States Food and Drug Administration , Estados Unidos
2.
Pharmacol Rev ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38914467

RESUMEN

The purpose of this review is to summarize essential biological, pharmaceutical and clinical aspects in the field of topically applied medicines that may help scientists when trying to develop new topical medicines. After a brief history of topical drug delivery, a review of the structure and function of the skin, routes of drug absorption and their limitations is then provided. The most prevalent diseases and current topical treatment approaches are then detailed, the organization of which reflects the key disease categories of autoimmune and inflammatory, microbial infections, skin cancers and genetic skin diseases. The complexity of topical product development through to large scale manufacture along with recommended risk mitigation approaches is then highlighted. As such topical treatments are applied externally patient preferences along with the challenges they invoke are then described and finally the future of this field of drug delivery is discussed with the emphasis on areas that are more likely to yield significant improvements over the topical medicines in current use or would expand the range of medicines and diseases treatable by this route of administration. Significance Statement This review of the key aspects the skin, its associated diseases and current treatments along with the intricacies of topical formulation development should be helpful in making judicious decisions about the development of new or improved topical medicines. These aspects include the choices of the active ingredients, formulations, the target patient populations preferences and limitations and the future with regards to new skin diseases and topical medicine approaches.

3.
Int J Pharm ; 656: 124012, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38537923

RESUMEN

Over the past decade, topically applied drug products have experienced extraordinary price increases, due to the shortage of multisource generic drug products. This occurrence is mainly related to the underlying challenges evolved in topical bioequivalence documentation. Although there has been continuing regulatory efforts to present surrogate in vitro methods to clinical endpoint studies, there is still a continued need for cost- and time-efficient alternatives that account for product specificities. Hence, this work intended to expose bioequivalence assessment issues for complex topical formulations, and more specifically those related with product efficacy guidance. As a model drug and product, a bifonazole 10 mg/g cream formulation was selected and two different batches of the commercially available Reference Product (RP) were used: RP1 that displayed lower viscosity and RP4 which presented high, but not the highest, viscosity. In vitro human skin permeation testing (IVPT) was carried out and the results were evaluated by means of the traditional bioequivalence assessment approach proposed by the EMA, as well as by the Scaled Average Bioequivalence assessment approach proposed by the FDA. Based on previous experience, there was an expectation of a high level of variability in the results, thus alternative methods to evaluate local drug skin availability were developed. More specifically, an infected skin disease model, where ex vivo human skin was infected and ATP levels were used as a biological marker for monitoring antifungal activity after product application. The results showed that permeation equivalence could not be supported between the different RP batches. In contrast, this statistical difference between the formulation batches was not indicated in the disease model. Nevertheless, in pivotal IVPT studies, the lowest permeant formulation (RP4) evidenced a higher antifungal in vitro activity as reported by the lower levels of ATP. A critical appraisal of the results is likewise presented, focusing on an outlook of the real applicability of the regulatory guidances on this subject.


Asunto(s)
Antifúngicos , Absorción Cutánea , Piel , Equivalencia Terapéutica , Humanos , Antifúngicos/farmacocinética , Antifúngicos/administración & dosificación , Piel/metabolismo , Administración Cutánea , Viscosidad , Técnicas In Vitro , Crema para la Piel/farmacocinética , Crema para la Piel/administración & dosificación
4.
Crit Rev Anal Chem ; : 1-42, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37665603

RESUMEN

The need for consistency in analytical method development reinforces the dependence of pharmaceutical product development and manufacturing on robust analytical data. The Analytical Quality by Design (AQbD), akin to the product Quality by Design (QbD) endows a high degree of confidence to the method quality developed. AQbD involves the definition of the analytical target profile as starting point, followed by the identification of critical method variables and critical analytical attributes, supported on risk assessment and design of experiment tools for the establishment of a method operable design region and control strategy of the method. This systematic approach moves away from reactive troubleshooting to proactive failure reduction. The objective of this review is to highlight the elements of the AQbD framework and provide an overview of their implementation status in various analytical methods used in the pharmaceutical field. These methodologies include but are not limited to, high-performance liquid chromatography, UV-Vis spectrophotometry, capillary electrophoresis, supercritical fluid chromatography, and high-performance thin-layer chromatography. Finally, a critical appraisal is provided to highlight how regulators have encouraged AQbD principles application to boost the prevention of method failures and a better understanding of the method operable design region (MODR) and control strategy, ultimately resulting in cost-effectiveness and regulatory flexibility.

5.
Artículo en Inglés | MEDLINE | ID: mdl-37527508

RESUMEN

In recent years, nanotechnology-based microRNA (miR) therapeutic platforms have shown great promise for immunotherapy and tissue regeneration, despite the unmet challenge of achieving efficient and safe delivery of miRs. The transport of miRs offers precision and regulatory value for a myriad of biological processes and pathways, including the control of macrophage (Mφ) functions and, consequently, the inflammatory cascades Mφ are involved in. Thus, enforcement of Mφ can boost the regenerative process and provide new solutions for diverse chronic pathologies. In this study, we sought to develop a magnetically guided transporter to deliver an miR-155 antagonist to M1-primed Mφ. Furthermore, we determined its modulatory effect in reprogramming Mφ from inflammatory to pro-regenerative phenotypes, with the aim of tissue healing and regenerative medicine approaches. This strategy combines contactless and high-precision control of Mφ, anticipating new functional miR carriers for targeted strategies controlled by extracorporeal action. The magnetoplexes SPION@PEI-miR were efficiently delivered into Mφ without compromising cell viability and successfully induced miR-mediated gene silencing by enhancing the expression of anti-inflammatory markers (IL4 and IL10) and the production of M2φ-related markers (CD206 and IL4). Given its multimodal features, SPION@PEI-miR represents a simple, safe, and nonviral theranostic platform that enables imaging, tracking, and miR delivery with modulatory effects on immune cells.

6.
Pharmaceutics ; 15(7)2023 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-37513997

RESUMEN

Analytical method validation ensures that a method provides trustworthy information about a particular sample when applied in accordance with the predefined protocol. According to regulatory standards, the rheological characteristics of topically applied semisolid formulations are one of the key elements involved in microstructure equivalence documentation. Therefore, for generic drug product manufacturers, it is a dire need to take a step forward in rheology method development and validation procedures. This paper aims to apply Analytical Quality by Design (AQbD) principles towards the development and validation of rheology methods for topical creams, as complex semisolid formulations. Risk assessment was carried out through an Ishikawa diagram and an estimate failure mode, effects, and criticality analysis (FMECA). Sample application, peltier temperature control, and sample rest time were identified as critical method variables (CMVs), and a 23 full factorial design was applied to understand their impact on rotational, creep recovery and, oscillatory measurements. The development of the method was carried out as per the ICH Q8-Q10, and Q14 guidelines and validated according to ICH Q2 (R2) guideline. The method demonstrated adequate precision (RSD < 15%), as well as selectivity. AQbD provided a comprehensive framework for developing a reliable and effective rheology method for this type of formulation.

7.
Eur J Pharm Biopharm ; 185: 94-106, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36806630

RESUMEN

In recent years, the regulatory mechanisms for topical generic product bioequivalence (BE) assessment have been subjected to noteworthy changes, with the FDA issuing product specific guidances, and the EMA adopting a more universal approach with the quality and equivalence of topical products draft guideline. The agencies advise on a modular strategy for BE documentation. Nevertheless, their scope, data analysis and criteria are rather distinct. This study aims to tackle bioequivalence assessment issues of complex topical formulations starting by statistical implications of the EMA/FDA approaches concerning the documentation of qualitative (Q1), quantitative (Q2), microstructure (Q3) and performance requirements (Q4). As a model drug product, a bifonazole 10 mg/g cream formulation was selected. For this specific formulation, the commercially available Reference Product (RP) was compared with two comparator products, also commercially available, referred to as comparator product A (CPA) and comparator product B (CPB). The former displays Q1 sameness and Q2 differences, whilst CPB is categorically considered as Q1/Q2 different. Furthermore, intending to establish a regulatory rationale for the submission of a generic product according to the updated regulatory requirements, the RP was likewise compared with a Test Product (TP). This formulation was designed to display equal Q1/Q2 profile to that of the RP. Validated rheology and in vitro release test (IVRT) methods were used to infer on Q3/Q4 characteristics. During rheology studies, statistically significant RP batch to batch differences were observed. Therefore, in an attempt to surpass this heterogeneity, the initial pool of RP batches was expanded to include RP product batches at different lifecycle stages. Despite this effort, it was not possible to classify the RP/TP, RP/CPA or RP/CPB as rheologically equivalent products. Nevertheless, product performance results, retrieved from IVRT, were able to sustain equivalence between the RP and the formulations exhibiting Q1 sameness (TP and CPA). It should however be mentioned, that for some RP batch combinations, the IVRT results failed to demonstrate equivalence according to the EMA requirements. Enlarging the RP batch pool was then a critical step in further understanding an optimum statistical approach for establishing equivalence in product performance. This study highlights the need to that a 'one-fits-all approach' may not be an optimum path way for establishing the regulatory strategy and requirements to support generic product bioequivalence.


Asunto(s)
Antifúngicos , Medicamentos Genéricos , Equivalencia Terapéutica , Medicamentos Genéricos/química , Técnicas In Vitro , Reología
8.
Int J Mol Sci ; 23(23)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36499452

RESUMEN

The persistence of inflammatory mediators in tissue niches significantly impacts regenerative outcomes and contributes to chronic diseases. Interleukin-4 (IL4) boosts pro-healing phenotypes in macrophages (Mφ) and triggers the activation of signal transducer and activator of transcription 6 (STAT6). Since the IL4/STAT6 pathway reduces Mφ responsiveness to inflammation in a targeted and precise manner, IL4 delivery offers personalized possibilities to overcome inflammatory events. Despite its therapeutic potential, the limited success of IL4-targeted delivery is hampered by inefficient vehicles. Magnetically assisted technologies offer precise and tunable nanodevices for the delivery of cytokines by combining contactless modulation, high tissue penetration, imaging features, and low interference with the biological environment. Although superparamagnetic iron oxide nanoparticles (SPION) have shown clinical applicability in imaging, SPION-based approaches have rarely been explored for targeted delivery and cell programming. Herein, we hypothesized that SPION-based carriers assist in efficient IL4 delivery to Mφ, favoring a pro-regenerative phenotype (M2φ). Our results confirmed the efficiency of SPION-IL4 and Mφ responsiveness to SPION-IL4 with evidence of STAT6-mediated polarization. SPION-IL4-treated Mφ showed increased expression of M2φ associated-mediators (IL10, ARG1, CCL2, IL1Ra) when compared to the well-established soluble IL4. The ability of SPION-IL4 to direct Mφ polarization using sophisticated magnetic nanotools is valuable for resolving inflammation and assisting innovative strategies for chronic inflammatory conditions.


Asunto(s)
Activación de Macrófagos , Nanopartículas , Humanos , Macrófagos/metabolismo , Mediadores de Inflamación/metabolismo , Inflamación/metabolismo
9.
Int J Mol Sci ; 23(19)2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36233094

RESUMEN

Hybrid nanoarchitectures such as magnetic polymeric micelles (MPMs) are among the most promising nanotechnology-enabled materials for biomedical applications combining the benefits of polymeric micelles and magnetic nanoparticles within a single bioinstructive system. MPMs are formed by the self-assembly of polymer amphiphiles above the critical micelle concentration, generating a colloidal structure with a hydrophobic core and a hydrophilic shell incorporating magnetic particles (MNPs) in one of the segments. MPMs have been investigated most prominently as contrast agents for magnetic resonance imaging (MRI), as heat generators in hyperthermia treatments, and as magnetic-susceptible nanocarriers for the delivery and release of therapeutic agents. The versatility of MPMs constitutes a powerful route to ultrasensitive, precise, and multifunctional diagnostic and therapeutic vehicles for the treatment of a wide range of pathologies. Although MPMs have been significantly explored for MRI and cancer therapy, MPMs are multipurpose functional units, widening their applicability into less expected fields of research such as bioengineering and regenerative medicine. Herein, we aim to review published reports of the last five years about MPMs concerning their structure and fabrication methods as well as their current and foreseen expectations for advanced biomedical applications.


Asunto(s)
Hipertermia Inducida , Micelas , Medios de Contraste , Sistemas de Liberación de Medicamentos/métodos , Polímeros/química , Medicina de Precisión
10.
Int J Pharm ; 628: 122265, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36216166

RESUMEN

Allergic contact dermatitis (ACD) is the most prevalent occupational disease and the most common form of immunotoxicity in humans. Preventing exposure to the triggering allergens is the mainstay of treatment. However, avoidance is not always possible in an occupational setting. From a pathophysiological point of view, a variety of events are involved in the development of ACD, including the formation of immunogenic complexes following the stable association of the allergen with skin proteins, which is thought to be the molecular initiating event responsible for the development of ACD. Previously, the team identified molecules that exhibited higher antiallergic potential due to their capacity to block the interaction between allergens and skin proteins. These assumptions were the starting point for the design of this work aiming to develop and characterize a new hydrogel containing the active ingredients lysine and N-acetyl cysteine under the premises of quality- and safety- by design. Two factorial plannings were established envisioning the optimization of the hydrogel in terms of mechanical and rheological properties. In vitro release and permeation studies supported its skin surface barrier effect. In addition, the selected hydrogel proved to be safe without causing human skin irritation or skin sensitization.


Asunto(s)
Dermatitis Alérgica por Contacto , Hidrogeles , Humanos , Dermatitis Alérgica por Contacto/prevención & control , Alérgenos , Piel
11.
Int J Pharm ; 620: 121705, 2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35358644

RESUMEN

Documenting topical bioequivalence can be an extremely complex process, which is intrinsically dependent on the formulation technological features. According to EMA guideline, for simple formulations, BE may be demonstrated by documenting the qualitative (Q1), quantitative (Q2), microstructure (Q3) and performance (Q4) equivalence. Nevertheless, when addressing complex semisolids, equivalence regarding local availability should also be demonstrated. The purpose of this study is to pursue this strategy using two opposite scenarios: a simple dimetindene maleate 1 mg/g gel formulation and a diclofenac diethylammonium 23.2 mg/g emulgel, representing a complex formulation. For both formulations, Q1/Q2 test (TP) and reference products (RP) were used. Rheology, in vitro release (IVRT) and in vitro permeation methods (IVPT) were developed and validated for both products. For the dimetindene formulation, equivalence pertaining to Q4 was established. However, high variability was observed for some rheology endpoints, especially for the different RP batches. Therefore, equivalence could not be established for Q3 as per EMA requirements. Can some rheology endpoints be waived? Can we establish reasonable criteria that are overall feasible for generic manufacturers and at the same time safe for the patient? An attempt was made to propose a wider acceptance range based on the inter-batch variability of the RP. For that, the rationale presented in the EMA guideline on bioequivalence for highly variable products was used. For the diclofenac formulation, Q3 equivalence was likewise not established. Q4 equivalence was only found for some batch combinations and when applying a wider acceptance criterion (75-133%). Furthermore, IVPT equivalence also failed to be demonstrated. Nevertheless, since the TP displays an equivalent pharmacokinetic profile compared to the RP, the observed Q3, Q4 and local availability differences are not expected to be clinically significant. This study draws attention to an effective search to determine the most appropriate strategy for assessing topical bioequivalence on a case-by-case basis.


Asunto(s)
Diclofenaco , Dimetindeno , Diclofenaco/química , Medicamentos Genéricos , Humanos , Técnicas In Vitro , Equivalencia Terapéutica
12.
Case Rep Ophthalmol Med ; 2021: 1056659, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34422421

RESUMEN

Eales' disease is a peripheral occlusive retinal phlebitis, with an unclear pathogenesis. The classic association with hypersensitivity to Mycobacterium tuberculosis protein infers that immunologic disturbance may be involved. Here, we described three cases of Eales' disease. All patients are Caucasian men aged 27-58 years and presented with vitreous hemorrhage and/or peripheral venous vasculitis. Tuberculin skin sensitive test (Mantoux screening test) and interferon-gamma release assay (IGRA) were positive in all patients. Therapeutic approach included antituberculosis therapy and systemic steroids, associated or not to immunosuppressive therapy, and retinal scatter photocoagulation in all cases. Antivascular endothelial grow factor (VEGF) intravitreal injections were also required in two cases. Since various retinal diseases can resemble this presentation, Eales' disease is considered a diagnosis of exclusion. Early diagnosis and appropriate therapeutic approach are both essential to accomplish disease control and reduce ophthalmologic complications.

13.
Case Rep Ophthalmol Med ; 2021: 1812271, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34123446

RESUMEN

Tubulointerstitial nephritis and uveitis syndrome (TINU) is a rare oculorenal inflammatory entity with a probable autoimmune etiology. Interstitial nephritis may be asymptomatic and usually has a benign course with spontaneous resolution. Uveitis, instead, is classically anterior, bilateral, and nongranulomatous, but it can be unilateral and presents as posterior uveitis or panuveitis, sometimes with a chronic or recurrent evolution. The frequent time lag of ocular and renal manifestations makes this diagnosis particularly challenging. The authors describe four cases of this rare entity, two with tubulointerstitial nephritis preceding ocular manifestations and the remaining, instead, with uveitis preceding renal involvement. The therapeutic approach included systemic corticosteroids in all cases. The addition of immunosuppressive therapy was required in three patients to achieve uveitis control. TINU is probably an underrecognized entity and should always be considered in the differential diagnosis of a chronic or recurrent idiopathic uveitis, especially in young patients who may have mild and asymptomatic renal disease.

14.
Rev. psicol. organ. trab ; 21(1): 1398-1406, jan.-mar. 2021. ilus
Artículo en Portugués | LILACS-Express | LILACS, INDEXPSI | ID: biblio-1252073

RESUMEN

A demissão é uma situação dramática que introduz o trabalhador na condição de desempregado, tendo consequências psicossociais para ele. O objetivo desse estudo foi analisar a vivência da demissão por trabalhadores desempregados em municípios interioranos. Partindo da Psicologia Histórico-Cultural, realizou-se entrevistas em profundidade com 21 participantes, abordando o processo de demissão, características do último emprego e a vivência da demissão em si, analisando as suas singularidades, particularidades e universalidade. As vivências foram heterogêneas quanto à dramaticidade do conflito da demissão, sendo mediadas por três determinantes principais: a comunicação prévia da demissão, permitindo um tempo para planejamento e desvinculação afetiva dos trabalhadores do seu contexto laboral; a esperança em conseguir um novo emprego ou fonte de renda; e a valorização de outras esferas de vida, principalmente, a família. Os achados reforçam a importância do aviso prévio, do seguro-desemprego e de ações organizacionais que construam, com os trabalhadores demitidos, projetos laborais pós-demissão.


Termination is a dramatic situation that introduces the condition of unemployment to workers, leading to psychosocial consequences for them. The objective of this study was to analyze the experience of unemployed workers concerning termination in countryside towns. Based on historical-cultural psychology, in-depth interviews were conducted with 21 participants addressing the process of termination, the characteristics of their last job, and the experience of termination in itself; analyzing its singularities, uniqueness, and universality. The experiences were heterogeneous regarding the dramatic aspect of the termination's conflict, and were mediated by three main determiners: 1) the previous notice of termination, allowing time for planning and the workers' emotional detachment from their context of work; 2) the hope to get a new job or source of income; and 3) the appreciation of other parts of their lives, especially family. The findings reinforce the importance of the notice of termination, of unemployment insurance, and of organizational actions that construct post-termination work projects with the terminated workers.


El despido es una situación dramática que coloca al trabajador en la condición de desempleado, teniendo consecuencias psicosociales. El objetivo de este estudio fue analizar la experiencia de despido de los trabajadores desempleados en los municipios del interior. Partiendo de la Psicología Histórico-Cultural, se realizaron entrevistas en profundidad con 21 participantes, abordando el proceso de despido, las características del último empleo y la experiencia del propio despido, analizando sus singularidades, particularidades y universalidad. Las experiencias fueron heterogéneas en cuanto al carácter dramático del conflicto del despido, siendo mediadas por tres determinantes principales: 1) la comunicación previa del despido, dando tiempo para la planificación y la desvinculación afectiva de los trabajadores de su contexto laboral; 2) la esperanza en la obtención de un nuevo empleo o fuente de ingresos; y 3) la valorización de otras esferas de vida, principalmente la familiar. Los hallazgos refuerzan la importancia del aviso previo, del seguro de desempleo y de las acciones organizacionales que promuevan, junto a los trabajadores despedidos, proyectos laborales posteriores al despido.

15.
J Foot Ankle Surg ; 60(3): 548-554, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33579548

RESUMEN

Lately there has been a growing interest in the use of percutaneous surgery for the correction of hallux valgus (HV). The purpose of the present study was to systematically review the published data about this topic and establish the efficacy and safety, stressing the complication rates found on this percutaneous technique. A systematic review of the literature available in PubMed was performed. The radiological and clinical outcomes were evaluated as well as complication rates. A total of 16 studies were included and 1157 procedures reported for percutaneous HV on 1246 patients. The mean angle correction of HV deformity improved postoperatively. Reported complications vary among the studies. The highest complication rate was joint stiffness in 18.47% of cases, followed by HV recurrence and shortening of M1, both in 15.2%, material intolerance in 10.1%, osteoarthritic changes in 9.1%, infection in 7.6%, and transfer metatarsalgia in 5.4%. There is a lack of randomized control trials and insufficient comparative case control studies to assess whether one technique is more effective than another or if the percutaneous surgery is recommended rather than open surgery with respect to complications.


Asunto(s)
Juanete , Hallux Valgus , Hallux Valgus/diagnóstico por imagen , Hallux Valgus/cirugía , Humanos , Procedimientos Quirúrgicos Mínimamente Invasivos , Osteotomía , Resultado del Tratamiento
16.
J Mater Chem B ; 9(5): 1259-1271, 2021 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-33410453

RESUMEN

In recent years, the inputs from magnetically assisted strategies have been contributing to the development of more sensitive screening methods and precise means of diagnosis to overcome existing and emerging treatment challenges. The features of magnetic materials enabling in vivo traceability, specific targeting and space- and time-controlled delivery of nanomedicines have highlighted the resourcefulness of the magnetic toolbox for biomedical applications and theranostic strategies. The breakthroughs in magnetically assisted technologies for contact-free control of cell and tissue fate opens new perspectives to improve healing and instruct regeneration reaching a wide range of diseases and disorders. In this review, the contribution of magnetic nanoparticles (MNPs) will be explored as sophisticated and versatile nanotriggers, evidencing their unique cues to probe and control cell function. As cells detect and engage external magnetic features, these approaches will be overviewed considering molecular engineering and cell programming perspectives as well as cell and tissue targeting modalities. The therapeutic relevance of MNPs will be also emphasized as key components of nanostructured systems to control the release of nanomedicines and in the context of new therapy technologies.


Asunto(s)
Técnicas Biosensibles/métodos , Fenómenos Magnéticos , Magnetismo/métodos , Humanos
17.
Artículo en Inglés | MEDLINE | ID: mdl-37641614

RESUMEN

Background: This study aimed to investigate retinal imaging biomarkers, such as disorganization of the retinal inner layers (DRIL) and/or ellipsoid zone (EZ) disruption by spectral domain optical coherence tomography (SD-OCT), and functional outcomes in eyes treated with 0.2 µg/day of a fluocinolone acetonide intravitreal implant (FAc) after an insufficient response to previous treatments. Methods: This was a retrospective comparative study of 18 eyes (15 patients) with persistent and/or recurrent diabetic macular edema (DME) treated with FAc. Eyes were divided according to the number of prior intravitreal treatments: group 1 (n = 8) with ≤ 6 injections (early switch) and group 2 (n = 10) with > 6 injections (late switch). Outcomes included percentage of eyes with DRIL and/or EZ disruption at baseline and analysis of the best corrected visual acuity (BCVA) using ETDRS letters, central macular thickness (CMT), DRIL, and EZ disruption at the last observation. Results: Group 2 revealed a significantly higher percentage of DRIL and/or EZ disruption than group 1 (P < 0.05). At the last observation, group 1 revealed a higher percentage of eyes achieving vision stability/ improvement, gaining ≥ 15 letters, and achieving ≥70 letters (P > 0.05 for all comparisons). The mean BCVA gain was 8.8 and 0.7 letters for groups 1 and 2 (P = 0.397). Both groups revealed a significant mean CMT reduction (> 20% reduction from the baseline value), without a significant statistical difference between them (P = 0.749). After treatment, most eyes from both groups showed resolution of DRIL and EZ disruption. Conclusions: Patients with DME presenting with a lower percentage of DRIL and/or EZ disruption at baseline had better functional outcomes, supporting the possible benefit of an early switch to FAc after insufficient response to previous treatments. Future randomized studies with a larger patient cohort are warranted to confirm our conclusions.

18.
Foot Ankle Surg ; 27(3): 296-300, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32586785

RESUMEN

BACKGROUND: Ankle injuries are one of the most common musculoskeletal disorder. The purpose of this study was to analyze and describe the detailed anatomical arrangement and relationship of posterior ligaments of the ankle, especially de posteroinferior tibiofibular ligament (PITFL) and intermalleolar ligament (IML). Controversy exists in the previous literature regarding their morphology and denomination, as well as the relation with ankle injuries including posterior soft tissue impingement syndrome. METHODS: Seventeen fresh-frozen cadaveric feet were used. The origins, insertions, ligament lengths, orientations with respect to relevant bony landmarks of the PITFL were evaluated. RESULTS: PITFL was present in all anatomical specimens. It was formed by two independent components, the superficial and deep fibers. Their dimensions vary widely between specimens. The IML was located between the deep PITFL and posterior talofibular ligament. The shape varied from a thin fibrous band to a thick cordlike structure. The IML was evident in 82.4% of the ankles. In 28.6% of the cases, the posterior intermalleolar ligament was split into two bundles in the fibular insertion. In 14 ankles, three slips were found. CONCLUSION: Given the frequency of injury and increasing necessity for surgical intervention, a more comprehensive anatomic knowledge of the different ligaments is warranted, provide clinically pertinent quantitative data and improve the treatment of these lesions.


Asunto(s)
Traumatismos del Tobillo/patología , Articulación del Tobillo/anatomía & histología , Ligamentos Laterales del Tobillo/anatomía & histología , Ligamentos Articulares/anatomía & histología , Tobillo/anatomía & histología , Cadáver , Peroné/anatomía & histología , Pie/anatomía & histología , Humanos , Tibia/anatomía & histología
19.
Rev. bras. oftalmol ; 80(3): e0002, 2021. graf
Artículo en Inglés | LILACS | ID: biblio-1251329

RESUMEN

ABSTRACT Conjunctival concretions are single or clustered lesions frequently found on the palpebral conjunctiva. They are commonly present in older individuals, despite being rarely symptomatic. This case report describes an 83-year-old man with multiple conjunctival concretions, which were surgically treated. The patient was symptomatic on presentation and did not respond to conservative treatment. For this reason, a surgical approach was considered. After wide excision of the conjunctival lesions, a piece of amniotic membrane was fitted using fibrin glue. During follow-up, a markedly improvement in patient's symptoms was observed, along with nearly complete absence of conjunctival concretions. This is the first case report addressing extensive conjunctival concretions with a surgical approach using amniotic membrane. The authors conceived the technique described after noticing the limited clinical options in the literature. This technique was easily performed and achieved satisfactory results.


RESUMO As concreções conjuntivais representam lesões amareladas, simples ou múltiplas, frequentemente encontradas na conjuntiva palpebral. São mais prevalentes em idades avançadas e raramente sintomáticas. Este relato de caso descreve o quadro clínico de um paciente de 83 anos com múltiplas concreções conjuntivais, cirurgicamente tratadas. Por se tratar de um paciente sintomático com resposta insuficiente ao tratamento conservador, foi considerada a abordagem cirúrgica. Após remoção das lesões, foi aplicado um enxerto de membrana amniótica, adaptado com cola de fibrina. No acompanhamento pós-operatório, verificou-se melhoria significativa dos sintomas, com desaparecimento quase total das concreções conjuntivais. Este é o primeiro caso que descreve uma abordagem cirúrgica com utilização de membrana amniótica na resolução desse tipo de lesões. A técnica, de fácil execução e com resultados muito favoráveis, foi desenvolvida pelos autores após constatarem a escassez de alternativas na literatura.


Asunto(s)
Humanos , Masculino , Anciano de 80 o más Años , Adhesivo de Tejido de Fibrina/uso terapéutico , Enfermedades de la Conjuntiva/cirugía , Litiasis/cirugía , Amnios/trasplante
20.
Pharm Res ; 37(11): 218, 2020 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-33037479

RESUMEN

PURPOSE: Following the recent European Medicine Agency (EMA) draft guideline on quality and equivalence of topical products, a modular framework for bioequivalence assessment is proposed, wherein the qualitative, quantitative, microstructure and product performance sameness is demanded to support generic applications. Strict regulatory limits are now imposed, but, the suitability of these limits has been subject of intense debate. In this context, this paper aims to address these issues by characterizing a panel of 8 reference blockbuster semisolid topical products. METHODS: For each product, three batches were selected and, whenever possible, batches retrieved from different manufacturing sites were considered. Product microstructure was evaluated in terms of globule size, pH, rheological attributes and, if required, the thermal behaviour was also assessed. Performance was evaluated through in vitro release testing (IVRT). Finally, an integrated multivariate analysis was performed to highlight the features that most contribute for product variability. RESULTS: Marked differences were registered within reference products. Statistical analysis demonstrated that if EMA criteria are applied, none of the same product batches can be considered as equivalent. Rheological parameters as well as IVRT indicators account for the majority of batch-to-batch differences. CONCLUSIONS: Semisolid dosage forms exhibit intrinsic variability. This calls for the attention to the need of establishing reasonable equivalence criteria applied to generic drug products. Graphical abstract.


Asunto(s)
Aprobación de Drogas , Medicamentos Genéricos/análisis , Tecnología Farmacéutica , Administración Tópica , Formas de Dosificación , Medicamentos Genéricos/administración & dosificación , Medicamentos Genéricos/normas , Control de Calidad , Equivalencia Terapéutica
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