Controlled release and antiviral activity of acyclovir-loaded PLA/PEG nanofibers produced by solution blow spinning.

Herpetic dermatitis and oral recurrent herpes (ORH) are among the most common human infections. Antiviral drugs such as acyclovir (ACV) are used in the standard treatment for ORH. Despite its therapeutic efficacy, ACV is continuously and repetitively administered in high doses. In this sense, the development of controlled release drug delivery systems such as core-shell fibers have a great potential in the treatment of ORH. In this work, poly(lactic acid)/poly(ethylene glycol) (PLA/PEG) fibers were produced by solution blow spinning (SBS) for the controlled release of ACV encapsulated in the core. PLA/PEG nanofibers containing four different blend ratios (100:0, 90:10, 80:20 and 70:30 wt%) without or with 10 wt% ACV were characterized by scanning electron microscopy (SEM), thermogravimetry (TG) and differential scanning calorimetry (DSC). The ACV release profile for 21 days was accessed by UV-Vis spectroscopy. Static water contact angles of the spun fiber mats were measured by the sessile drop method to evaluate fiber wettability upon contact with skin for transdermal release. Cytotoxicity and antiviral efficacy against Herpes simplex viruses (HSV-1) were evaluated using Vero cells. ACV addition did not impact on morphology, but slightly improved thermal stability of the fibers. Addition of hydrophilic PEG in PLA/PEG blends, however, increased drug release as confirmed by contact angle measurements and release profile. The in vitro tests showed the effectiveness of the drug delivery systems developed in reducing HSV-1 viral titer, which is related to the judicious combination of polymers used in the fibrous mats, in addition to not being cytotoxic to Vero cells. These results show the great potential of PLA/PEG solution blow-spun fibers in the controlled release of ACV to develop practical devices for the treatment of cold sores, while favoring the aesthetic appearance by covering them with a soft tissue patch (fibrous mats).

Catechins as Model Bioactive Compounds for Biomedical Applications.

Research regarding polyphenols has gained prominence over the years because of their potential as pharmacological nutrients. Most polyphenols are flavanols, commonly known as catechins, which are present in high amounts in green tea. Catechins are promising candidates in the field of biomedicine. The health benefits of catechins, notably their antioxidant effects, are related to their chemical structure and the total number of hydroxyl groups. In addition, catechins possess strong activities against several pathogens, including bacteria, viruses, parasites, and fungi. One major limitation of these compounds is low bioavailability. Catechins are poorly absorbed by intestinal barriers. Some protective mechanisms may be required to maintain or even increase the stability and bioavailability of these molecules within living organisms. Moreover, novel delivery systems, such as scaffolds, fibers, sponges, and capsules, have been proposed. This review focuses on the unique structures and bioactive properties of catechins and their role in inflammatory responses as well as provides a perspective on their use in future human health applications.

Immunoglobulin Therapy in a Patient With Severe Chikungunya Fever and Vesiculobullous Lesions.

Chikungunya virus (CHIKV) is an emerging arbovirus whose transmission has already been reported in several countries. Although the majority of individuals acutely infected with CHIKV appear to become asymptomatic, reports showing the occurrence of atypical and severe forms of the disease are increasing. Among them, the neurological and skin manifestations require medical attention. Treatment of CHIKV infection is almost symptomatic. In this sense, we report the case of a 56-years-old man who presented fever, headaches, paresthesia and pain in the right arm with visible red spots on the skin starting 30 days before Hospital admission. Tests determined Chikungunya infection and excluded other co-morbidities. Disease evolved with edema in hands and feet and extensive hemorrhagic bullous lesions on the skin of upper and lower limbs. Variations in hematological counts associated with liver dysfunction determined this patient's admission to the Intensive Care Unit. Then, he received intravenous antibiotic and immunoglobulin therapy (400 mg/Kg/day for the period of 5 days) with total recovery from the lesions after 10 days of follow-up. A general improvement in blood cell count and successful wound healing was observed. After discharge, no other clinical sign of the disease was reported until nowadays. This case reports for the first time the successful administration of intravenous immunoglobulin therapy to a patient with severe atypical dermatological form of Chikungunya Fever without any associated comorbidity.

Plant Extracts Loaded in Nanostructured Drug Delivery Systems for Treating Parasitic and Antimicrobial Diseases.

BACKGROUND: Plant extracts loaded in nanostructured drug delivery systems (NDDSs) have been reported as an alternative to current therapies for treating parasitic and antimicrobial diseases. Among their advantages, plant extracts in NDSSs increase the stability of the drugs against environmental factors by promoting protection against oxygen, humidity, and light, among other factors; improve the solubility of hydrophobic compounds; enhance the low absorption of the active components of the extracts (i.e., biopharmaceutical classification II), which results in greater bioavailability; and control the release rate of the substances, which is fundamental to improving the therapeutic effectiveness. In this review, we present the most recent data on NDDSs using plant extracts and report results obtained from studies related to in vitro and in vivo biological activities.