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1.
Chemistry ; 30(30): e202400582, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38501912

ABSTRACT

The unique biophysical and biochemical properties of intrinsically disordered proteins (IDPs) and their recombinant derivatives, intrinsically disordered protein polymers (IDPPs) offer opportunities for producing multistimuli-responsive materials; their sequence-encoded disorder and tendency for phase separation facilitate the development of multifunctional materials. This review highlights the strategies for enhancing the structural diversity of elastin-like polypeptides (ELPs) and resilin-like polypeptides (RLPs), and their self-assembled structures via genetic fusion to ordered motifs such as helical or beta sheet domains. In particular, this review describes approaches that harness the synergistic interplay between order-promoting and thermoresponsive building blocks to design hybrid biomaterials, resulting in well-structured, stimuli-responsive supramolecular materials ordered on the nanoscale.


Subject(s)
Biocompatible Materials , Elastin , Peptides , Biocompatible Materials/chemistry , Elastin/chemistry , Elastin/genetics , Peptides/chemistry , Intrinsically Disordered Proteins/chemistry , Intrinsically Disordered Proteins/genetics , Temperature , Humans , Insect Proteins
2.
Water Res ; 233: 119802, 2023 Apr 15.
Article in English | MEDLINE | ID: mdl-36871379

ABSTRACT

20 years since the first report on the biofouling potential of chemicals used for scale control, still, antiscalants with high bacterial growth potential are used in practice. Evaluating the bacterial growth potential of commercially available antiscalants is therefore essential for a rational selection of these chemicals. Previous antiscalant growth potential tests were conducted in drinking water or seawater inoculated with model bacterial species which do not represent natural bacterial communities. To reflect better on the conditions of desalination systems, we investigated the bacterial growth potential of eight different antiscalants in natural seawater and an autochthonous bacterial population as inoculum. The antiscalants differed strongly in their bacterial growth potential varying from ≤ 1 to 6 µg easily biodegradable C equivalents/mg antiscalant. The six phosphonate-based antiscalants investigated showed a broad range of growth potential, which depended on their chemical composition, whilst the biopolymer and the synthetic carboxylated polymers-based antiscalants showed limited or no significant bacterial growth. Moreover, nuclear magnetic resonance (NMR) scans enabled antiscalant fingerprinting, identifying components and contaminants, providing a rapid and sensitive characterization, and opening opportunities for rational selection of antiscalants for biofouling control.


Subject(s)
Biofouling , Water Purification , Seawater/chemistry , Osmosis , Membranes, Artificial
3.
Cell Biochem Funct ; 40(6): 636-646, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35848411

ABSTRACT

Melatonin (MEL) has antioxidant properties and participates in osteogenic differentiation. In periodontitis, in which increased oxidative stress and bone resorption are involved, mesenchymal stem cells derived from the gingiva (GMSCs) combined with MEL could be relevant for osteogenic regeneration. In this study, we studied the antioxidant and differentiating effect of MEL on an in vitro system of GMSCs. Primary culture of GMSCs from Wistar rats was developed to evaluate differentiation into osteoblasts with an appropriate medium with or without MEL. Marker genes of mesenchymal stem cells by real time-polymerase chain reaction, clonogenic capacity, and cell migration after wound assay were used to characterize GMSCs as mesenchymal stem cells. Alkaline phosphatase activity and the alizarin red technique were used to evaluate osteogenic activity and differentiation. MEL increased alkaline phosphatase activity and alizarin red values, promoting osteogenic differentiation. Besides this, MEL protected GMSCs in a model of cellular damage related to oxidative stress, returning viability to baseline. MEL was more effective in promoting and protecting GMSCs by the production of osteogenic cells when oxidative stress is present. This evidence supports the use of MEL as a novel bone-regenerative therapy in periodontal diseases.


Subject(s)
Melatonin , Mesenchymal Stem Cells , Alkaline Phosphatase/pharmacology , Animals , Antioxidants/pharmacology , Cell Differentiation , Cells, Cultured , Gingiva , Melatonin/pharmacology , Osteoblasts , Osteogenesis , Rats , Rats, Wistar
4.
Eur J Appl Physiol ; 122(4): 945-954, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35059801

ABSTRACT

PURPOSE: The aim of the present investigation is to study the relationship of ventricular global longitudinal strain (GLS) and ultrasound lung comets (ULC) formation to establish a link between extravascular pulmonary water formation and cardiac contractile dysfunction. METHODS: This is a prospective observational study including 14 active military divers. The subjects performed two sea dives of 120 min each with a semi-closed SCUBA circuit at 10 m depth. Divers were examined at baseline, 15 min (D1) and 60 min (D2) after diving. The evaluation included pulmonary and cardiac echography (including speckle tracking techniques). Blood samples were drawn at baseline and after diving, assessing hs-TnT and Endothelin-1. RESULTS: ULC were detected in 9 (64.2%) and 8 (57.1%) of the subjects after D1 and D2 respectively. No differences were found in right and left ventricular GLS after both immersions (RV: Baseline: - 17.9 4.9 vs. D1: - 17.2 6.5 and D2: - 16.7 5.8 s-1; p = 0.757 and p = 0.529; LV: Baseline: - 17.0 2.3 vs. D1: - 17.4 2.1 and D2: - 16.9 2.2 s-1; p = 0.546 and p = 0.783). However, a decrease in atrial longitudinal strain parameters have been detected after diving (RA: Baseline: 35.5 9.2 vs. D1: 30.3 12.8 and D2: 30.7 13.0 s-1; p = 0.088 and p = 0.063; LA: Baseline: 39.0 10.0 vs. D1: 31.6 6.1 and D2: 32.4 10.6 s-1; p = 0.019 and p = 0.054). CONCLUSION: In the present study, no ventricular contractile dysfunction was observed. However, increase pulmonary vasoconstriction markers were present after diving.


Subject(s)
Diving , Extravascular Lung Water , Echocardiography , Extravascular Lung Water/diagnostic imaging , Humans , Myocardial Contraction , Ultrasonography
5.
Cir. plást. ibero-latinoam ; 47(2): 201-210, abril-junio 2021. ilus
Article in Spanish | IBECS | ID: ibc-217353

ABSTRACT

La reconstrucción del cuero cabelludo por una lesión en scalp es compleja debido a las características morfológicas del cráneo.Presentamos el caso de una paciente de 44 años remitida al Hospital Universitario de La Samaritana (Bogotá, Colombia), con un scalp masivo de espesor total que comprometía el 95% de la superficie y para el cual usamos un colgajo muscular quimérico libre de dorsal ancho y serrato anterior, con posterior cobertura del mismo mediante injertos de piel de espesor parcial.El colgajo adoptó el contorno natural del cráneo; no hubo complicaciones ni necesidad de una revisión secundaria. Los injertos generaron un adecuado resultado funcional y estético que permite el uso de pelucas.No se presentaron otras de las desventajas que se observan con diferentes opciones de reconstrucción. (AU)


Reconstruction of scalp is complex due to cranial morphological traits.A 44-year-old patient is referred to Hospital Universitario de La Samaritana (Bogotá, Colombia) with a massive scalp defect affecting 95% of its total surface and total thickness. A chimeric muscular free flap of the latissimus dorsi and anterior serratus is used to cover the defect; posteriorly, a split-thickness skin graft was placed to cover the flap.The flap adapted to the natural cranial contour without complications; no secondary surgical revision was necessary. Additionally, the skin graft achieved an adequate aesthetic and functional result that allows the use of wigs without other irregularities that could be observed with other reconstructive options. (AU)


Subject(s)
Humans , Female , Middle Aged , Scalp , Surgery, Plastic , Transplants , Skin , Post Disaster Reconstruction
6.
J Periodontal Res ; 56(1): 154-161, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32965035

ABSTRACT

BACKGROUND AND OBJECTIVE: Cellular damage related to oxidative stress (OS) is implicated in periodontal diseases (PD). Melatonin (MEL) has multiple functions, and it has been described as a potential treatment for PD. We aim at evaluating the protective effects of MEL on an in vitro model of cellular damage triggered by glutamate (GLUT) and DL-buthionine sulfoximine (BSO), on gingival cells (GCs) in culture. MATERIAL AND METHODS: A primary culture of GCs from Wistar rats was developed in order to test the protective property of MEL; BSO and GLUT were administered alone as well as in combination with MEL. The viability and apoptosis were measured with MTT assay and TUNEL, respectively, and the concentration of superoxide anion ( O 2 - ) was measured with the NBT method. RESULTS: The combination of BSO and GLUT treatment resulted in a decreased viability of GCs. This was evidenced by the increase in both the production of superoxide anion and apoptosis. After MEL administration, the oxidant and pro-apoptotic effects of BSO and GLUT were totally counteracted. CONCLUSIONS: These findings demonstrated that MEL has an effective protective role on GCs subjected to cellular damage in a model of OS and cytotoxicity triggered by BSO and GLUT. Consequently, MEL could be used as a therapeutic agent in PD which begin with a significative loss of GCs.


Subject(s)
Melatonin , Animals , Buthionine Sulfoximine/toxicity , Glutamic Acid , Glutathione , Melatonin/pharmacology , Rats , Rats, Wistar
7.
Forensic Sci Int Genet ; 49: 102391, 2020 11.
Article in English | MEDLINE | ID: mdl-32957016

ABSTRACT

One of the main goals of the Spanish and Portuguese-Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) is to promote and contribute to the development and dissemination of scientific knowledge in the field of forensic genetics. The GHEP-ISFG supports several Working Commissions which develop different scientific activities. One of them, the Working Commission on "Massively Parallel Sequencing (MPS): Forensic Applications", organized its first collaborative exercise on forensic applications of MPS technology in 2019. The aim of this exercise was to assess the concordance between the MPS results and those obtained with conventional technologies (capillary electrophoresis and Sanger sequencing), as well as to compare the results obtained within the different MPS platforms and/or the different kits/panels and analysis software packages (commercial and open-access) available on the market. The seven participating laboratories analyzed some samples of the annual GHEP-ISFG proficiency test (EIADN No. 27 (2019)), using Ion Torrent™ or MiSeq FGx® platforms. Six of them sent autosomal STR sequence data, five laboratories performed MPS analysis of individual identification SNPs, four laboratories reported MPS data of Y-chromosomal STRs, and X-chromosomal STRs, three laboratories performed MPS analysis of ancestry informative SNPs and phenotype informative SNPs, two labs performed MPS analysis of the mitochondrial DNA control region, and only one lab produced MPS data of lineage informative SNPs. Autosomal STR sequencing results were highly concordant to the consensus obtained by capillary electrophoresis in the EIADN No. 27 (2019) exercise. Furthermore, in general, a high level of concordance was observed between the results of the participating laboratories, regardless of the platform used. The main discordances were due to errors during the analysis process or from sequence data obtained with low depth of coverage. In this paper we highlight some issues that still arise, such as standardization of the nomenclature for STRs analyzed by sequencing with MPS, the universal uptake of a nomenclature framework by the analysis software, and well established validation and accreditation of the new MPS platforms for use in routine forensic case-work.


Subject(s)
High-Throughput Nucleotide Sequencing/standards , Laboratories/standards , Chromosomes, Human, X , Chromosomes, Human, Y , DNA, Mitochondrial/genetics , Forensic Genetics/standards , Humans , Microsatellite Repeats , Polymorphism, Single Nucleotide , Sequence Analysis, DNA , Societies, Scientific
8.
P R Health Sci J ; 37(Spec Issue): S66-S72, 2018 12.
Article in English | MEDLINE | ID: mdl-30576580

ABSTRACT

The world has encountered a new and serious epidemic which has disproportionately affected fetuses and infants. What makes the Zika virus (ZIKV) epidemic such a threat in our times, is that a whole generation can be affected by birth defects caused by a seemingly innocuous maternal infection, which in most cases go unnoticed and undiagnosed. Spreading to over 80 countries and affecting millions, it is associated with severe birth defects known as congenital Zika syndrome (CZS), which include fetal brain development abnormalities (microcephaly and brain calcifications), retinal abnormalities, and contractures and hypertonia of the extremities. Testing strategies are challenging because of the lack of symptoms and cross reactivity with other viral infections. Obstetrical complications include fetal loss and the need for an emergency cesarean delivery. The rate of CZS has been described as ranging from 5 to 6% among cohorts in the US, reaching 11% for 1st trimester exposure. Prolonged viremia during pregnancy has been documented in a few cases, reaching 89 days after the onset of symptoms in one case and 109 days after such onset in another. If the ZIKV can infect, multiply in, and persist in diverse placental cells, then movement across the placenta, the fetal brain, and the maternal peripheral blood is possible. There is a sense of urgency, and we need safe and effective vaccines and treatments, particularly for pregnant women. If we do not expand testing and develop methods for early diagnosis and treatment, thousands of infants will be exposed to a neurotropic virus that causes severe birth defects and that could also affect the lives of those who form the next generation.


Subject(s)
Congenital Abnormalities/virology , Pregnancy Complications, Infectious/virology , Zika Virus Infection/epidemiology , Brain/abnormalities , Brain/virology , Congenital Abnormalities/epidemiology , Epidemics , Female , Humans , Infant, Newborn , Microcephaly/epidemiology , Microcephaly/virology , Pregnancy , Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/epidemiology , Pregnancy Outcome , Zika Virus Infection/congenital , Zika Virus Infection/diagnosis
9.
HIV AIDS (Auckl) ; 10: 57-61, 2018.
Article in English | MEDLINE | ID: mdl-30804684

ABSTRACT

The reduction in the mother-to-infant transmission of HIV has been among the early successes of care and treatment of women living with HIV. Prenatal HIV counseling and testing, the availability of diverse antiretroviral therapies, elective cesarean section, and the use of formula milk have significantly reduced the mother-to-infant transmission in the USA and Europe. We are presenting two cases of seroconversion during pregnancy, identified during labor and delivery, of women who received risk reduction counseling and serial HIV testing during pregnancy. Because there are no guidelines for (or easy access to) the use of pre-exposure prophylaxis (PrEP) in pregnancy, they were offered other strategies for prevention including risk reduction counseling, condoms, and serial HIV testing. These cases support the use of PrEP during pregnancy. Both infants were negative and the women are currently receiving long-term highly active antiretroviral therapy. One of them recently delivered another infant. After these two women seroconverted, we decided to offer PrEP to all pregnant women presenting for care who report having an HIV positive partner. During the period 2012-2014, we treated ten HIV negative pregnant women who were partners of HIV positive men. Since 2015, we have seen 20 pregnant women in HIV discordant relationships. Of those, seven received PrEP. No seroconversions have been observed among the pregnant women on PrEP. Although small numbers, seroconversion during pregnancy was observed in two of 13 (15%) of the pregnant women in HIV-discordant relationships seen in our clinic, excluding those treated with PrEP. Given the safety data and experience with tenofovir and emtricitabine among pregnant women living with HIV, we believe PrEP should be offered in pregnancy and that guidelines should reflect this option as an additional strategy to reduce risks during pregnancy and to further reduce infant HIV transmission risk.

10.
Article in English | MEDLINE | ID: mdl-30159551

ABSTRACT

OBJECTIVES: To evaluate the impact of group prenatal care (Centering Pregnancy) on the rate of Preterm Birth (PTB) and low birth weight. Women were enrolled into Centering Pregnancy (Transformación Prenatal) if they fell in the category of poverty, and had at least one risk for PTB according to known risk factors for low birth weight or PTB. METHODS: Mother's age, parity, risk factors, prenatal/delivery complications, infants' Gestational Age (GA), birth weight, Apgar scores, delivery route, indications for delivery, and use of Neonatal Intensive Care Unit (NICU) were abstracted from charts of mothers who received group or traditional care at the University Hospital in San Juan, PR. RESULTS: More infants were born at term if the mothers received Centering Pregnancy. The mean birth weight and gestational age of the infants were higher (6.59 vs. 6.33 lbs. and 37.8 vs. 36.8 weeks) than for those in traditional care. Centering Pregnancy also had lower rates of preterm birth (27.7% vs. 34.1%) and births earlier than 31 weeks (2.8% vs. 9.9%). All were statistically significant (P<0.05). CONCLUSIONS: We successfully implemented group prenatal care (Centering Pregnancy) for the first time in PR in a complex environment: tertiary care hospital with a high-risk prenatal clinic. Despite having known risk factors for preterm birth, the mothers in Centering Pregnancy had better outcomes. In an environment of adverse determinants of health, the program was effective in reducing the odds for adverse infant outcomes early in life and demonstrating that innovative models of health care can improve such outcomes.

11.
Front Psychol ; 7: 1117, 2016.
Article in English | MEDLINE | ID: mdl-27516749

ABSTRACT

The advance of the Internet and new technologies over the last decade has transformed the retailing panorama. More and more channels are emerging, causing consumers to change their habits and shopping behavior. An omnichannel strategy is a form of retailing that, by enabling real interaction, allows customers to shop across channels anywhere and at any time, thereby providing them with a unique, complete, and seamless shopping experience that breaks down the barriers between channels. This paper aims to identify the factors that influence omnichannel consumers' behavior through their acceptance of and intention to use new technologies during the shopping process. To this end, an original model was developed to explain omnichannel shopping behavior based on the variables used in the UTAUT2 model and two additional factors: personal innovativeness and perceived security. The model was tested with a sample of 628 Spanish customers of the store Zara who had used at least two channels during their most recent shopping journey. The results indicate that the key determinants of purchase intention in an omnichannel context are, in order of importance: personal innovativeness, effort expectancy, and performance expectancy. The theoretical and managerial implications are discussed.

12.
Article in English | MEDLINE | ID: mdl-28529970

ABSTRACT

On February 1, 2016, the World Health Organization (WHO) declared the Zika virus outbreak a Public Health Emergency of International Concern (PHEIC). Because Zika virus is a relatively new infection with several transmission routes that include mosquito bites, sexual and possibly blood-related, we present the case for a parallel between the Zika epidemic and the AIDS epidemic for issues that relate particularly to pregnancy and epidemic response. We will discuss the many similarities between both epidemics while acknowledging that the viruses are different and the pathophysiology and disease manifestation are also different. What can we learn of the three decades of awareness campaigns, community involvement, clinical, behavior and prevention research, activism and policy-making related to HIV/AIDS? How can the lessons and experience of dealing with the HIV epidemic can help us deal with the ongoing Zika epidemic? Is there a roadmap that we can follow? Our position is that we can and we should. Parallels between the Zika and HIV/AIDS epidemics particularly in relation to pregnancy can be established. Lessons and successes from the HIV/AIDS epidemic control efforts can guide us towards comprehensive approaches to improve the health of women and infants at risk for Zika.

13.
P R Health Sci J ; 31(3): 170-9, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23038893

ABSTRACT

Recent advances in the field of biomedical prevention have induced optimism among both the scientific community and the public in general. The discussion of the research evidence is complemented with a discussion of the implications of this evidence for the Caribbean, highlighting the issues and controversies that should be considered in order to encourage and advance the responsible consideration of biomedical strategies. Traditionally, HIV prevention strategies have been characterized as predominantly behavior, social or biomedical. In practice, however, some strategies defy classification: even when they rely on technological or pharmaceutical elements, they have to be adopted by a society and the individuals within it. Moreover, whatever the strategy used, it will have to be distributed, implemented and made available through health care systems or other means. And its cost will be absorbed by specific funders or by society in general. Given the current historical context of the HIV/AIDS epidemic and the array of strategies required to control it, these distinctions (biomedical vs. behavior) can hinder the collaborations required to provide the needed combinations of strategies. The efficacy of the diverse strategies range from: 99% for programs to prevent MTCT, 63% for pre-exposure prophylaxis (PrEP), 96% for treatment as prevention, 39% for vaginal microbicides (54% with good adherence), post exposure prophylaxis (PEP), 31% for a vaccine and 53-60% for medical voluntary adult circumcision. To curtail and eliminate the HIV/AIDS epidemic in the future, expansion and scaled-up implementation of combinations of such strategies will be needed.


Subject(s)
HIV Infections/epidemiology , HIV Infections/prevention & control , Health Policy , Primary Prevention/methods , Public Health , Biomedical Research , Caribbean Region/epidemiology , Humans
14.
BMC Genomics ; 12: 326, 2011 Jun 23.
Article in English | MEDLINE | ID: mdl-21699700

ABSTRACT

BACKGROUND: Epidermal Growth Factor (EGF) is a key regulatory growth factor activating many processes relevant to normal development and disease, affecting cell proliferation and survival. Here we use a combined approach to study the EGF dependent transcriptome of HeLa cells by using multiple long oligonucleotide based microarray platforms (from Agilent, Operon, and Illumina) in combination with digital gene expression profiling (DGE) with the Illumina Genome Analyzer. RESULTS: By applying a procedure for cross-platform data meta-analysis based on RankProd and GlobalAncova tests, we establish a well validated gene set with transcript levels altered after EGF treatment. We use this robust gene list to build higher order networks of gene interaction by interconnecting associated networks, supporting and extending the important role of the EGF signaling pathway in cancer. In addition, we find an entirely new set of genes previously unrelated to the currently accepted EGF associated cellular functions. CONCLUSIONS: We propose that the use of global genomic cross-validation derived from high content technologies (microarrays or deep sequencing) can be used to generate more reliable datasets. This approach should help to improve the confidence of downstream in silico functional inference analyses based on high content data.


Subject(s)
Epidermal Growth Factor/pharmacology , Gene Expression Profiling , Oligonucleotide Array Sequence Analysis/methods , Sequence Analysis, DNA/methods , HeLa Cells , Humans , Meta-Analysis as Topic , Metabolic Networks and Pathways/genetics , Metallothionein/genetics , Metallothionein/metabolism , Signal Transduction , Software
15.
Rev. CIEZT ; 4(5): 90-3, ene.-dic. 1999.
Article in Spanish | LILACS | ID: lil-263845

ABSTRACT

La criptococosis es una enfermedad infecciosa causada por un hongo levaduriforme denominado Cryptococcus neoformans, agente oportunista que ataca a pacientes inmudeprimidos. Se describe un caso clínico que cursó con esta patología teniendo como enfermedad base el SIDA. En este paciente la infección se localizó en el sistema nervioso central, confirmándose el diagnóstico mediante coloración en tinta china y cultivo en medio de Sabourand. Como terapia antifúngica se administró fuconazol intravenoso con resultados favorables.


Subject(s)
Male , Adult , Cryptococcosis/diagnosis , Cryptococcosis/therapy
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