Nanotechnology and the future of condoms in the prevention of sexually transmitted infections

Rethinking the application of nanoparticles in women's reproductive health and assisted reproduction

Nanoparticles and nanotechnology may present opportunities to revolutionize the prevention, treatment and diagnosis of a range of reproductive health conditions in women. These technologies are also used to improve outcomes of assisted reproductive technology. We highlight a range of these potential clinical uses of nanoparticles for polycystic ovary syndrome, endometriosis, uterine fibroids and sexually transmitted infections, considering in vitro and in vivo studies along with clinical trials. In addition, we discuss applications of nanoparticles in assisted reproductive technology, including sperm loading, gamete and embryo preservation and preventing preterm birth. Finally, we present some of the concerns associated with the medical use of nanoparticles, identifying routes for further exploration before nanoparticles can be applied to women's reproductive health in the clinic.

Establishing a prediction model for recurrence of condyloma acuminatum

We collected the clinical data of 156 patients diagnosed with condyloma acuminatum (CA), including age, gender, marriage, education level, stay up late, smoking, drinking, number of sexual partners, HPV infection status of sexual partners, genitourinary and anal diseases, condom use, other diseases of HPV infection, location and number of warts, HPV typing, etc. Analyze the risk factors affecting the recurrence of CA, explore the influencing factors and independent influencing factors of CA recurrence, establish the prediction model of CA recurrence, and evaluate its prediction value. Univariate analysis showed that stay up late, HPV infection status of sexual partners, urogenital diseases, condom use, other diseases of HPV infection and the number of CA were the influencing factors of CA recurrence. Multivariate analysis showed that condom use (OR = 0.166), HPV infection status of sexual partners (OR = 4.848), number of warts (OR = 1.212) and urogenital diseases (OR = 3.179) were independent factors affecting the recurrence of CA (P < 0.05). Therefore, the prediction model of CA recurrence can be established, and the area under the curve AUC of the prediction model was calculated to be 0.867 (95% CI 0.812–0.923). The model established in this study has certain prediction value for the recurrence of CA and can be used to preliminarily predict the recurrence of CA.

SABERES E MODOS DE AGIR DE HOMENS RIBEIRINHOS SOBRE O USO DE PRESERVATIVO

RESUMO Objetivo analisar os saberes e modos de agir de homens ribeirinhos acerca o uso do preservativo, a partir de suas representações sociais sobre o dispositivo. Método estudo qualitativo ancorado na Teoria das Representações Sociais, realizado com 21 homens ribeirinhos da comunidade São Carlos do Jamari, em Porto Velho, Rondônia, Brasil. A coleta de dados ocorreu entre janeiro e julho de 2019, por meio de entrevista com questionário semiestruturado. Para o processamento dos dados utilizou-se os softwares Statistical Package for the Social Sciences, obtendo-se a caracterização dos participantes por meio da estatística descritiva e o IRAMUTEq®, para análise lexical dos discursos, pela classificação hierárquica descente, obtendo-se cinco classes temáticas, dentre as quais, aprofundou-se neste estudo a classe cinco. Resultados as representações sociais foram produzidas por participantes adultos, com ensino médio completo, renda familiar per capita de até um salário-mínimo, sexualmente ativos com uso irregular do preservativo. Identificou-se que os participantes elaboram uma dimensão cognitiva, que revela seus saberes sobre o preservativo como forma de prevenção, contudo, elementos como interferência no prazer, relacionamento estável e uma dimensão avaliativa negativa resultam no uso irregular do dispositivo e num comportamento de risco, em suas práticas sexuais. Conclusão as representações sociais se ancoram no conhecimento reificado, no discurso da funcionalidade preventiva do preservativo e em estereótipos de masculinidade. Com isso, os homens ribeirinhos possuem um conhecimento que não se manifesta em seus comportamentos. Portanto, esse grupo social carece de ações de promoção da saúde que possibilitem mudanças em seus comportamentos e práticas de cuidados.

RIVERSIDE MEN'S KNOWLEDGE AND WAYS OF ACTING REGARDING CONDOM USE

ABSTRACT Objective to analyze riverside men's knowledge and ways of acting regarding condom use, based on the social representations about the device. Method a qualitative study anchored in the Theory of Social Representations and conducted with 21 riverside men from the São Carlos do Jamari community, Porto Velho, Rondônia, Brazil. Data collection was performed between January and July 2019 by means of an interview with a semi-structured questionnaire. For data processing, the Statistical Package for the Social Sciences software was used, obtaining the participants' characterization through descriptive statistics, in addition to IRAMUTEq® for the lexical analysis of the speeches, by means of the Descending Hierarchical Classification, obtaining five thematic classes, among which Class 5 was deepened on in this study. Results the social representations were produced by adult participants, with complete High School, per capita family income of up to one minimum wage, and sexually active with irregular condom use. It was identified that the participants develop a cognitive dimension, which reveals their knowledge about condoms as a form of prevention; however, elements such as interference in pleasure, stable relationship and a negative evaluative dimension result in irregular use of the device and in risky behaviors in their sexual practices. Conclusion social representations are anchored in reified knowledge, in the discourse of the preventive functionality of condoms, and in masculinity stereotypes. Consequently, the riverside men's knowledge is not manifested in their behaviors. Therefore, this social group lacks health promotion actions that enable changes in their care behaviors and practices.

The Factors Determining the Skin Penetration and Cellular Uptake of Nanocarriers: New Hope for Clinical Development

The skin provides a protective barrier against toxic environments and also offers a valuable route for topical drug delivery. The stratum corneum (SC) is the outermost layer of the skin and serves as the major barrier to chemical transfer through the skin. The human skin barrier is particularly difficult to overcome because of the complex composition and structure of the SC. Nanoparticulate carriers have gained widespread attention in topical drug delivery due to their tunable and versatile properties. The present review summarizes the main factors involved in skin penetration of nanocarriers containing the drug. Employment of nanotechnology in topical delivery has grown progressively during recent years; however, it is important to monitor the skin penetration of nanocarriers prior to their use to avoid possible toxic effects. Nanocarriers can act as a means to increase skin permeation of drugs by supporting direct interaction with the SC and increasing the period of permanence on the skin. Skin penetration is influenced by the physicochemical characteristics of nanocarriers such as composition, size, shape, surface chemistry, as well as skin features. Considering that the target of topical systems based on nanocarriers is the penetration of therapeutic agents in the skin layers, so a detailed understanding of the factors influencing skin permeability of nanocarriers is essential for safe and efficient therapeutic applications.

Engineered nanoparticle bio-conjugates toxicity screening: The xCELLigence cells viability impact

Introduction: The vast diverse products and applications of engineered nanoparticle bio-conjugates (ENPBCs) are increasing, and thus flooding the-markets. However, the data to support risk estimates of ENPBC are limited. While it is important to assess the potential benefits, acceptability and uptake, it is equally important to understand where ENPBCs safety is and how to expand and affirm consumer security concerns. Methods: Online articles were extracted from 2013 to 2016 that pragmatically used xCELLigence real-time cell analysis (RTCA) technology to describe the in-vitro toxicity of ENPBCs. The xCELLigence is a +noninvasive in vitro toxicity monitoring process that mimics exact continuous cellular bio-responses in real-time settings. On the other hand, articles were also extracted from 2008 to 2016 describing the in vivo animal models toxicity of ENPBCs with regards to safety outcomes. Results: Out of 32 of the 121 (26.4%) articles identified from the literature, 23 (71.9%) met the in-vitro xCELLigence and 9(28.1%) complied with the in vivo animal model toxicity inclusion criteria. Of the 23 articles, 4 of them (17.4%) had no size estimation of ENPBCs. The xCELLigence technology provided information on cell interactions, viability, and proliferation process. Eighty-three (19/23) of the in vitro xCELLigence technology studies described ENPBCs as nontoxic or partially nontoxic materials. The in vivo animal model provided further toxicity information where 1(1/9) of the in vivo animal model studies indicated potential animal toxicity while the remaining results recommended ENPPCs as potential candidates for drug therapy though with limited information on toxicity. Conclusion: The results showed that the bioimpacts of ENPBCs either at the in vitro or at in vivo animal model levels are still limited due to insufficient information and data. To keep pace with ENPBCs biomedical products and applications, in vitro, in vivo assays, clinical trials and long-term impacts are needed to validate their usability and uptake. Besides, more real-time ENPBCs-cell impact analyses using xCELLigence are needed to provide significant data and information for further in vivo testing.

Preparation and characterization of a novel thermosensitive and bioadhesive cephalexin nanohydrogel: a promising platform for topical antibacterial delivery

OBJECTIVE

Impetigo is a common and highly contagious bacterial skin infection that mostly affects young children and infants. Herein, we report the development of a thermosensitive and bioadhesive in-situ hydrogel-forming system containing cephalexin-loaded nanoparticles (NPs) suitable for antibacterial drug delivery.

METHODS

The nanohydrogel was formulated using drug-loaded NPs and characterized by its physicochemical characteristics. Antibacterial activities of the cephalexin NPs and nanohydrogel were examined in vitro against Staphylococcus aureus (S. aureus). The ex vivo drug permeation study was performed using rat skin. Finally, this formulation was tested for in vivo antibacterial activity using superficial skin infections in rats.

RESULTS

The mean size and entrapment efficiency of the NPs were found to be 178 nm and 58%, respectively. The transmission electron microscopy analysis verified the formation of spherical NPs. The drug-loaded NPs showed an enhanced eradication effect against S. aureus according to the declined MIC values in comparison with the untreated drug. The ex vivo permeation profile of the cephalexin nanohydrogel showed a slow release pattern for 8 h. When applied on rat skin for 6 days, the nanohydrogel exhibited a superior antibacterial activity with normal hair growth and skin appearance as compared to the plain drug hydrogel.

CONCLUSIONS

These findings suggested that the nanohydrogel could serve as a valuable drug delivery platform against superficial bacterial infections.

A brief overview on nano-sized materials used in the topical treatment of skin and soft tissue bacterial infections

Introduction: Skin and soft tissue infections are a significant clinical problem that can happen anywhere on the body. Bacteria are the most common cause of skin and soft tissue infections in humans. Despite the fact that there is a lot of antimicrobial agents and antibiotics for elucidating bacterial infections, the prevention and control of infectious diseases continue to be one of the greatest challenges for public health worldwide. At the present time, an alarming increase in multidrug resistance instantly requests to find suitable alternatives to current antibiotics. Therefore, drug resistance has been attempted to be resolved by the development of new classes of antimicrobial agents or targeted delivery systems for antibacterial drugs using nanotechnology.Area covered: The present review summarizes the emerging topical efforts to support the use of nano-sized materials as a new opportunity to combat today's skin infectious diseases.Expert opinion: Nano-sized materials can overcome the stratum corneum barrier and deliver drugs specifically to bacterial skin infections with trivial side effects. Depending on the physicochemical characteristics of nano-scaled materials, they can specifically be selected to target bacterial pathogens and also to get into the skin layers. These systems can overcome the antibiotic-resistance mechanisms and help us to the design of novel topical formulations that will make administration of antibacterial compounds safer, easier and more convenient.

In Situ Modification of Polyisoprene by Organo-Nanoclay during Emulsion Polymerization for Reinforcing Natural Rubber Thin Films

Nanoclay-modified polyisoprene latexes were prepared and then used as a reinforcing component in natural rubber (NR) thin films. Starve-fed emulsion (SFE) polymerization gives a higher conversion than the batch emulsion (BE), while the gel and coagulation contents from both systems are comparable. This is attributed to the SFE that provides a smaller average polymer particle size which in turn results in a greater polymerization locus, promoting the reaction rate. The addition of organo-nanoclay during synthesizing polyisoprene significantly lessens the polymerization efficiency because the nanoclay has a potential to suppress nucleation process of the reaction. It also intervenes the stabilizing efficiency of the surfactant—SDS or sodium dodecyl sulfate, giving enlarged average sizes of the polymer particles suspended in the latexes. TEM images show that nanoclay particles are attached on and/or inserted in the polymer particles. XRD and thermal (differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA)) analyses were employed to assess the d-spacing of nanoclay structure in NR nanocomposite films, respectively. Based on the overall results, 5 wt% of nanoclay relative to the monomer content utilized to alter the polyisoprene during emulsion polymerization is an optimum amount since the silicate plates of nanoclay in the composite exhibit the largest d-spacing which maximizes the extent of immobilized polymer constituent, giving the highest mechanical properties to the films. The excessive amounts of nanoclay used, i.e., 7 and 10 wt% relative to the monomer content, reduce the reinforcing power because of the re-agglomeration effect.