Bioengineering of fibroblast-conditioned polycaprolactone/gelatin electrospun scaffold for skin tissue engineering

Background Synthetic tissue engineering scaffolds has poor biocompatiblity with very low angiogenic properties. Conditioning the scaffolds with functional groups, coating with biological components, especially extracellular matrix (ECM), is an excellent strategy for improving their biomechanical and biological properties. Methods In the current study, a composite of polycaprolactone and gelatin (PCL/Gel) was electrospun in the ratio of 70/30 and surface modified with 1% gelatin-coating (G-PCL/Gel) or plasma treatment (P-PCL/Gel). The surface modification was determined by SEM and ATR-FTIR spectroscopy, respectively. The scaffolds were cultured with fibroblast 3T3, then decellularized during freeze-thawing process to fabricate a fibroblast ECM-conditioned PCL/Gel scaffold (FC-PCL/Gel). The swelling and degaradtion as well as in vitro and in vivo biocompatibility and angiogenic properties of the scaffolds were evaluated. Results The structure of the surface-modified G-PCL/Gel and P-PCL/Gel were unique and not changed compared with the PCL/Gel scaffolds. ATR-FTIR analysis admitted the formation of oxygen-containing groups, hydroxyl and carboxyl, on the surface of the P-PCL/Gel scaffold. The SEM micrographs and DAPI staining confirmed the cell attachment and the ECM deposition on the platform and successful removal of the cells after decellularization. P-PCL/Gel showed better cell attachment, ECM secretion and deposition after decellularization compared with G-PCL/Gel. The FC-PCL/Gel was considered as an optimized scaffold for further assays in this study. The FC-PCL/Gel showed increased hydrophilic behavior and cytobiocompatibility compared with P-PCL/Gel. The ECM on the FC-PCL/Gel scaffold showed a gradual degradation during 30 days of degradation time, as a small amount of ECM remained over the FC-PCL/Gel scaffold at day 30. The FC-PCL/Gel showed significant biocompatibility and improved angiogenic property compared with P-PCL/Gel when subcutaneously implanted in a mouse animal model for 7 and 28 days. Conclusions Our findings suggest FC-PCL/Gel as an excellent biomimetic construct with high angiogenic properties. This bioengineered construct can serve as a possible application in our future pre-clinical and clinical studies for skin regeneration.We express our sincere thanks to Dr Mohammad Amin Haramshahi, Dr Sara Simorgh, and Miss Roya Sajed for helpful comments on this work. This study is extracted from the thesis written by Ayna Yazdanpanah and funded by a grant from the Iran University of Medical Sciences under grant number y(33225) and the animal study ethical committee confirmation code of IR.IUMS. REC.1397.469. SCK is European Research Area Chair in the FoReCaST project (European Commission—H2020- WIDESPREAD-2014-668983) and FCT—Portuguese project BREAST-IT (PTDC/BTM-ORG/28168/2017) supported SCK

Human papillomavirus (HPV69/HPV73) coinfection associated with simultaneous squamous cell carcinoma of the anus and presumed lung metastasis

Background: Human papillomaviruses (HPVs) have been linked to a variety of human cancers. As the landscape of HPV-related neoplasia continues to expand, uncommon and rare HPV genotypes have also started to emerge. Host-virus interplay is recognized as a key driver in HPV carcinogenesis, with host immune status, virus genetic variants and coinfection highly influencing the dynamics of malignant transformation. Immunosuppression and tissue tropism are also known to influence HPV pathogenesis. Methods: Herein, we present a case of a patient who, in the setting of HIV positivity, developed anal squamous cell carcinoma associated with HPV69 and later developed squamous cell carcinoma in the lungs, clinically presumed to be metastatic disease, associated with HPV73. Consensus PCR screening for HPV was performed by real-time PCR amplification of the L1 gene region, amplification of the E6 regions with High-Resolution Melting Curve Analysis followed by Sanger sequencing confirmation and phylogenetic analysis. Results: Sanger sequencing of the consensus PCR amplification product determined that the anal tissue sample was positive for HPV 69, and the lung tissue sample was positive for HPV 73. Conclusions: This case underscores the importance of recognizing the emerging role of these rare 'possibly carcinogenic' HPV types in human carcinogenesis. © 2020 by the authors. Licensee MDPI, Basel, Switzerland

Is the genetic variability of elite rice in southern Brazil really disappearing?

There is a worldwide concern about a possible narrowing of the genetic base of most crops, as e.g. that of rice (Oryza sativa L.), as a result of the modern breeding practices. Thus, the purpose of this study was to investigate this phenomenon in the germplasm of elite paddy rice in southern Brazil, including frequently used accessions in crosses. The panel consisted of 91 accessions. Data of morphological traits, SNP markers and mineral content of husked and polished grain were analyzed by hierarchical clustering and principal component analysis. The SNP markers and hierarchical clustering proved most appropriate to assess the genetic variability. A narrowing of the genetic base of rice was confirmed, although a certain level of genetic variability was still found in the germplasm of elite paddy rice in south Brazilian rice, particularly for grain mineral content

The importance of antioxidant biomaterials in human health and technological innovation: a review.

ABSTRACT: Biomaterials come from natural sources such as animals, plants, fungi, algae, and bacteria, composed mainly of protein, lipid, and carbohydrate molecules. The great diversity of biomaterials makes these compounds promising for developing new products for technological applications. In this sense, antioxidant biomaterials have been developed to exert biological and active functions in the human body and industrial formulations. Furthermore, antioxidant biomaterials come from natural sources, whose components can inhibit reactive oxygen species (ROS). Thus, these materials incorporated with antioxidants, mainly from plant sources, have important effects, such as anti-inflammatory, wound healing, antitumor, and anti-aging, in addition to increasing the shelf-life of products. Aiming at the importance of antioxidant biomaterials in different technological segments as biodegradable, economic, and promising sources, this review presents the main available biomaterials, antioxidant sources, and assigned biological activities. In addition, potential applications in the biomedical and industrial fields are described with a focus on innovative publications found in the literature in the last five years

Resurgence of vaccine-preventable diseases in Venezuela as a regional public health threat in the Americas

Venezuela’s tumbling economy and authoritarian rule have precipitated an unprecedented humanitarian crisis. Hyperinflation rates now exceed 45,000%, and Venezuela’s health system is in free fall. The country is experiencing a massive exodus of biomedical scientists and qualified healthcare professionals. Reemergence of arthropod-borne and vaccine-preventable diseases has sparked serious epidemics that also affect neighboring countries. In this article, we discuss the ongoing epidemics of measles and diphtheria in Venezuela and their disproportionate impact on indigenous populations. We also discuss the potential for reemergence of poliomyelitis and conclude that action to halt the spread of vaccine-preventable diseases within Venezuela is a matter of urgency for the country and the region. We further provide specific recommendations for addressing this crisis. © 2019 Centers for Disease Control and Prevention (CDC). All rights reserved

First wave of COVID-19 in Venezuela:Epidemiological, clinical, and paraclinical characteristics of first cases

The coronavirus disease 2019 (COVID-19) pandemic has particularly affected countries with weakened health services in Latin America, where proper patient management could be a critical step to address the epidemic. In this study, we aimed to characterize and identify which epidemiological, clinical, and paraclinical risk factors defined COVID-19 infection from the first confirmed cases through the first epidemic wave in Venezuela. A retrospective analysis of consecutive suspected cases of COVID-19 admitted to a sentinel hospital was carried out, including 576 patient cases subsequently confirmed for severe acute respiratory syndrome coronavirus 2 infection. Of these, 162 (28.1%) patients met the definition criteria for severe/critical disease, and 414 (71.2%) were classified as mild/moderate disease. The mean age was 47 (SD 16) years, the majority of which were men (59.5%), and the most frequent comorbidity was arterial hypertension (23.3%). The most common symptoms included fever (88.7%), headache (65.6%), and dry cough (63.9%). Severe/critical disease affected mostly older males with low schooling (p < 0.001). Similarly, higher levels of glycemia, urea, aminotransferases, total bilirubin, lactate dehydrogenase, and erythrocyte sedimentation rate were observed in severe/critical disease patients compared to those with mild/moderate disease. Overall mortality was 7.6% (44/576), with 41.7% (28/68) dying in hospital. We identified risk factors related to COVID-19 infection, which could help healthcare providers take appropriate measures and prevent severe clinical outcomes. Our results suggest that the mortality registered by this disease in Venezuela during the first epidemic wave was underestimated. An increase in fatalities is expected to occur in the coming months unless measures that are more effective are implemented to mitigate the epidemic while the vaccination process is ongoing

Desigualdade no acesso a medicamentos para doenças crônicas em mulheres brasileiras

O objetivo deste trabalho foi analisar a prevalência de acesso a medicamentos para tratamento de doenças crônicas e a existência de desigualdades socioeconômicas no acesso. Os dados são da Pesquisa Nacional de Demografia e Saúde e da Mulher e da Criança de 2006, com uma amostra de 15.575 mulheres (15 a 49 anos). Dessas, 7.717 tiveram diagnóstico de doença crônica com necessidade de obtenção de medicamento e foram consideradas elegíveis para o estudo. O desfecho foi construído com base no diagnóstico de doença crônica e na necessidade de obtenção de medicamento para o tratamento. A análise ajustada foi conduzida usando-se a regressão de Poisson. Os grupos que apresentaram maior prevalência de acesso foram os domiciliados na zona rural, com uma ou duas doenças crônicas e com nível socioeconômico mais elevado. A prevalência de acesso encontrada foi alta, no entanto, as análises demonstram que existe desigualdade socioeconômica no acesso a medicamentos a favor dos mais ricos, identificando como grupo mais vulnerável aquele dos indivíduos mais pobres e com maior número de doenças crônicas

The relationships between exogenous and endogenous antioxidants with the lipid profile and oxidative damage in hemodialysis patients

Background: We sought to investigate the relationships among the plasma levels of carotenoids, tocopherols, endogenous antioxidants, oxidative damage and lipid profiles and their possible effects on the cardiovascular risk associated with hemodialysis (HD) patients. Methods: The study groups were divided into HD and healthy subjects. Plasma carotenoid, tocopherol and malondialdehyde (MDA) levels, as well as erythrocyte reduced glutathione (GSH), were measured by HPLC. Blood antioxidant enzymes, kidney function biomarkers and the lipid profiles were analyzed by spectrophotometric methods. Results: Plasma lycopene levels and blood glutathione peroxidase (GPx) activity were significantly decreased in HD patients compared with healthy subjects. Total cholesterol, low-density lipoprotein cholesterol (LDL-c), creatinine, urea, MDA, GSH, superoxide dismutase (SOD) and catalase (CAT) were significantly increased in HD (p < 0.05). Lycopene levels were correlated with MDA (r = -0.50; p < 0.01), LDL-c (r = -0.38; p = 0.01) levels, the LDL-c/HDL-c index (r = -0.33; p = 0.03) and GPx activity (r = 0.30; p = 0.03). Regression models showed that lycopene levels were correlated with LDL-c (β estimated = -31.59; p = 0.04), while gender was correlated with the TC/HDL-c index and triglycerides. Age did not present a correlation with the parameters evaluated. GPx activity was negatively correlated with MDA levels and with the LDL-c/HDL-c and CT/HDL-c indexes. Conclusions: Lycopene may represent an additional factor that contributes to reduced lipid peroxidation and atherogenesis in hemodialysis patients

Tegumentary leishmaniasis and coinfections other than HIV

<div><p>Background</p><p>Tegumentary leishmaniasis (TL) is a disease of skin and/or mucosal tissues caused by <i>Leishmania</i> parasites. TL patients may concurrently carry other pathogens, which may influence the clinical outcome of TL.</p><p>Methodology and principal findings</p><p>This review focuses on the frequency of TL coinfections in human populations, interactions between <i>Leishmania</i> and other pathogens in animal models and human subjects, and implications of TL coinfections for clinical practice. For the purpose of this review, TL is defined as all forms of cutaneous (localised, disseminated, or diffuse) and mucocutaneous leishmaniasis. Human immunodeficiency virus (HIV) coinfection, superinfection with skin bacteria, and skin manifestations of visceral leishmaniasis are not included. We searched MEDLINE and other databases and included 73 records: 21 experimental studies in animals and 52 studies about human subjects (mainly cross-sectional and case studies). Several reports describe the frequency of <i>Trypanosoma cruzi</i> coinfection in TL patients in Argentina (about 41%) and the frequency of helminthiasis in TL patients in Brazil (15% to 88%). Different hypotheses have been explored about mechanisms of interaction between different microorganisms, but no clear answers emerge. Such interactions may involve innate immunity coupled with regulatory networks that affect quality and quantity of acquired immune responses. Diagnostic problems may occur when concurrent infections cause similar lesions (e.g., TL and leprosy), when different pathogens are present in the same lesions (e.g., <i>Leishmania</i> and <i>Sporothrix schenckii</i>), or when similarities between phylogenetically close pathogens affect accuracy of diagnostic tests (e.g., serology for leishmaniasis and Chagas disease). Some coinfections (e.g., helminthiasis) appear to reduce the effectiveness of antileishmanial treatment, and drug combinations may cause cumulative adverse effects.</p><p>Conclusions and significance</p><p>In patients with TL, coinfection is frequent, it can lead to diagnostic errors and delays, and it can influence the effectiveness and safety of treatment. More research is needed to unravel how coinfections interfere with the pathogenesis of TL.</p></div