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1.
ACS Nano ; 18(36): 24803-24811, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39177501

RESUMEN

The preparation of artificial diamonds has a long history driven by decreased costs compared to naturally occurring diamonds and ethical issues. However, fabrication of diamonds in the laboratory from readily available biomass has not been extensively investigated. This work demonstrates a convenient method for producing nanodiamonds from biopolymer lignin at ambient pressure. Lignin was extracted from Douglas Fir sawdust using a butanosolv pretreatment and was pyrolyzed in N2 at 1000 °C, followed by a second thermal treatment in 5% H2/Ar at 1050 °C, both at ambient pressure. This led to the formation of nanodiamonds embedded in an amorphous carbon substrate. The changes occurring at various stages of the pyrolysis process were monitored by scanning electron microscopy, Fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy. High resolution transmission electron microscopy revealed that nanodiamond crystallites, 4 nm in diameter on average, formed via multiple nucleation events in some carbon-containing high density spheres. It is proposed that highly defected graphene-like flakes form during the pyrolysis of lignin as an intermediate phase. These flakes are more deformable with more localized π electrons in comparison with graphene and join together face-to-face in different manners to form cubic or hexagonal nanodiamonds. This proposed mechanism for the formation of nanodiamonds is relevant to the future fabrication of diamonds from biomass under relatively mild conditions.

2.
J Med Entomol ; 61(4): 919-924, 2024 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-38687673

RESUMEN

Mosquitoes play a critical role as vectors of pathogens affecting both humans and animals. Therefore, understanding their biodiversity and distribution is crucial to developing evidence-based vector control strategies. The current study updated the composition and distribution of mosquito species through a comprehensive survey of all municipalities of Cabo Verde. From October 2017 to September 2018, mosquito larvae and pupae were collected from 814 aquatic habitats. Anopheles gambiae (Giles, 1902) and Culex pipiens (Linnaeus, 1758) complexes were subjected to PCR-based techniques for sibling species identification. Ten mosquito species from 5 genera were identified: Aedes aegypti (Linnaeus, 1762), Aedes caspius (Pallas, 1771), Anopheles arabiensis (Patton, 1905), Anopheles pretoriensis (Theobald, 1903), Culex bitaeniorhynchus (Giles, 1901), Cx. pipiens, Culex quinquefasciatus (Say, 1823), Culex tritaeniorhynchus (Giles, 1901), Culiseta longiareolata (Macquart, 1838), and Lutzia tigripes (de Grandpre & de Charmoy, 1901). Santiago Island reported the highest number of species (n = 8). Ae. aegypti and Cx. quinquefasciatus were the most widely distributed species across the country. An. arabiensis was the sole species identified within the An. gambiae complex. The findings from our study will help guide health policy decisions to effectively control mosquito-borne diseases.


Asunto(s)
Distribución Animal , Culicidae , Mosquitos Vectores , Animales , Culicidae/clasificación , Cabo Verde , Biodiversidad , Larva/crecimiento & desarrollo , Pupa/crecimiento & desarrollo , Enfermedades Transmitidas por Vectores/transmisión , Enfermedades Transmitidas por Vectores/prevención & control , Enfermedades Transmitidas por Mosquitos
3.
J Med Entomol ; 61(3): 791-797, 2024 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-38402515

RESUMEN

Mosquito-borne diseases can pose significant burdens. In many countries, they pose a risk to national economies and the well-being of humans and animals. To mitigate this, mosquito surveillance is crucial to assess the real and potential transmission of mosquito-borne diseases. Between 2020 and 2023, mosquito larvae were collected from both indoor and outdoor breeding sites in urban and rural areas of 4 municipalities of Santiago and Boavista Islands in Cabo Verde. Mosquitoes were identified morphologically and by polymerase chain reaction-based techniques that targeted the mitochondrial cytochrome C oxidase subunit I sequence. During this period, 6,825 breeding sites were assessed, and of 8,094 mosquito specimens screened, 194 specimens of Culex thalassius were identified for the first time in the country in 4 municipalities of Santiago and Boavista Islands. This new finding highlights the importance of including entomological surveillance in health systems. Although this species has only been detected on a few islands, it is important to continuously monitor it to determine its distribution, spread/dispersal, density, and potential involvement in pathogen transmission.


Asunto(s)
Distribución Animal , Culex , Larva , Animales , Larva/crecimiento & desarrollo , Larva/clasificación , Cabo Verde , Mosquitos Vectores/genética , Complejo IV de Transporte de Electrones/análisis , Complejo IV de Transporte de Electrones/genética
4.
Molecules ; 28(23)2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38067614

RESUMEN

Environmentally acceptable and renewably sourced flame retardants are in demand. Recent studies have shown that the incorporation of the biopolymer lignin into a polymer can improve its ability to form a char layer upon heating to a high temperature. Char layer formation is a central component of flame-retardant activity. The covalent modification of lignin is an established technique that is being applied to the development of potential flame retardants. In this study, four novel modified lignins were prepared, and their char-forming abilities were assessed using thermogravimetric analysis. The lignin was obtained from date palm wood using a butanosolv pretreatment. The removal of the majority of the ester groups from this heavily acylated lignin was achieved via alkaline hydrolysis. The subsequent modification of the lignin involved the incorporation of an azide functional group and copper-catalysed azide-alkyne cycloaddition reactions. These reactions enabled novel organophosphorus heterocycles to be linked to the lignin. Our preliminary results suggest that the modified lignins had improved char-forming activity compared to the controls. 31P and HSQC NMR and small-molecule X-ray crystallography were used to analyse the prepared compounds and lignins.

5.
ACS Sustain Chem Eng ; 11(39): 14323-14333, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37799817

RESUMEN

Cocoa pod husks (CPHs) represent an underutilized component of the chocolate manufacturing process. While industry's current focus is understandably on the cocoa beans, the husks make up around 75 wt % of the fruit. Previous studies have been dominated by the carbohydrate polymers present in CPHs, but this work highlights the presence of the biopolymer lignin in this biomass. An optimized organosolv lignin isolation protocol was developed, delivering significant practical improvements. This new protocol may also prove to be useful for agricultural waste-derived biomasses in general. NMR analysis of the high quality lignin led to an improved structural understanding, with evidence provided to support deacetylation of the lignin occurring during the optimized pretreatment. Chemical transformation, using a tosylation, azidation, copper-catalyzed click protocol, delivered a modified lignin oligomer with an organophosphorus motif attached. Thermogravimetric analysis was used to demonstrate the oligomer's potential as a flame-retardant. Preliminary analysis of the other product streams isolated from the CPHs was also carried out.

6.
Contemp Clin Trials ; 125: 107037, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36460267

RESUMEN

BACKGROUND: HIV disproportionally affects persons who inject drugs (PWID), but engagement with HIV pre-exposure prophylaxis (PrEP) is low. We describe the rationale and study design for a new study, "Contingency Management and Pre-Exposure Prophylaxis (PrEP) Adherence Support Services (CoMPASS)," a hybrid type 1 effectiveness-implementation trial to promote HIV risk reduction among PWID. METHODS: In four community-based programs in the northeastern United States, PrEP-eligible PWID (target n = 526) are randomized to treatment as usual or Contingency Management (CM) and, as indicated, stepped up to PrEP Adherence Support Services (CoMPASS) over 24 weeks. During CM sessions, participants receive timely tangible rewards for verifiable activities demonstrating 1) PrEP initiation and adherence, and 2) engagement with medications for opioid use disorder (MOUD) and other OUD-related care. Participants who do not have high levels of biomarker-confirmed PrEP adherence at week 12 will be stepped up to receive PrEP Adherence Support Services (PASS) consisting of strengths-based case management over 12 weeks. Interventions are delivered by trained PrEP navigators, staff embedded within the respective sites. The primary outcome is sustained PrEP adherence by dried blood spot testing at 24 weeks. To inform future implementation, we are conducting implementation-focused process evaluations throughout the clinical trial. CONCLUSIONS: Results from this protocol are anticipated to yield novel findings regarding the impact and scalability of CoMPASS to promote HIV prevention among PWID in partnership with community-based organizations. http://ClinicalTrials.gov identifier: NCT04738825.


Asunto(s)
Fármacos Anti-VIH , Consumidores de Drogas , Infecciones por VIH , Profilaxis Pre-Exposición , Abuso de Sustancias por Vía Intravenosa , Humanos , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Fármacos Anti-VIH/uso terapéutico , Profilaxis Pre-Exposición/métodos , Abuso de Sustancias por Vía Intravenosa/complicaciones , Conducta de Reducción del Riesgo
7.
Implement Sci Commun ; 2(1): 64, 2021 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-34112269

RESUMEN

BACKGROUND: Describe and evaluate an implementation science network focused on HIV prevention and treatment in New England. METHODS: In 2014, we established a partnership among university researchers and community stakeholders to stimulate and support HIV-related implementation research. We solicited information from Network members through surveys, interviews at Network events, and dialog with participants. In 2017, we conducted a sociocentric network assessment of collaborations on research projects, grants, manuscripts, and consultations. RESULTS: We identified 988 connections made through the Network that resulted in 185 manuscripts published and 15 grants funded. Our experience indicated that eight factors were instrumental in building and sustaining the Network: (1) acknowledging different perspectives, (2) balancing content and expertise, (3) encouraging consistent engagement, (4) providing seed funding, (5) membership flexibility, (6) maintenance of Network interactions, (7) supporting local HIV prevention and treatment efforts, and (8) maintaining productive relationships with health departments and community-based organizations. CONCLUSIONS: Developing and maintaining a regional network on implementation science for HIV prevention and treatment is feasible and can facilitate new and productive partnerships among researchers and community organizations and members.

8.
Artículo en Inglés | MEDLINE | ID: mdl-32079356

RESUMEN

BACKGROUND: Mosquito-borne viruses, such as Zika, dengue, yellow fever, and chikungunya, are important causes of human diseases nearly worldwide. The greatest health risk for arboviral disease outbreaks is the presence of the most competent and highly invasive domestic mosquito, Aedes aegypti. In Cabo Verde, two recent arbovirus outbreaks were reported, a dengue outbreak in 2009, followed by a Zika outbreak in 2015. This study is the first entomological survey for Ae. aegypti that includes all islands of Cabo Verde archipelago, in which we aim to evaluate the actual risk of vector-borne arboviruses as a continuous update of the geographical distribution of this species. METHODS: In order to assess its current distribution and abundance, we undertook a mosquito larval survey in the nine inhabited islands of Cabo Verde from November 2018 to May 2019. Entomological larval survey indices were calculated, and the abundance analyzed. We collected and identified 4045 Ae. aegypti mosquitoes from 264 positive breeding sites in 22 municipalities and confirmed the presence of Ae. aegypti in every inhabited island. Results: Water drums were found to be the most prevalent containers (n = 3843; 62.9%), but puddles (n = 27; 0.4%) were the most productive habitats found. The overall average of the House, Container, and Breteau larval indices were 8.4%, 4.4%, and 10.9, respectively. However, 15 out of the 22 municipalities showed that the Breteau Index was above the epidemic risk threshold. CONCLUSION: These results suggest that if no vector control measures are considered to be in place, the risk of new arboviral outbreaks in Cabo Verde is high. The vector control strategy adopted must include measures of public health directed to domestic water storage and management.


Asunto(s)
Aedes , Distribución Animal , Infecciones por Arbovirus/transmisión , Mosquitos Vectores , Aedes/virología , Animales , Infecciones por Arbovirus/prevención & control , Cabo Verde , Fiebre Chikungunya , Dengue , Virus del Dengue , Brotes de Enfermedades/prevención & control , Ecosistema , Humanos , Insectos Vectores/virología , Larva , Mosquitos Vectores/virología , Salud Pública , Medición de Riesgo , Virus Zika , Infección por el Virus Zika
9.
Biochim Biophys Acta ; 1854(8): 1019-37, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25900361

RESUMEN

The Enzyme Function Initiative, an NIH/NIGMS-supported Large-Scale Collaborative Project (EFI; U54GM093342; http://enzymefunction.org/), is focused on devising and disseminating bioinformatics and computational tools as well as experimental strategies for the prediction and assignment of functions (in vitro activities and in vivo physiological/metabolic roles) to uncharacterized enzymes discovered in genome projects. Protein sequence similarity networks (SSNs) are visually powerful tools for analyzing sequence relationships in protein families (H.J. Atkinson, J.H. Morris, T.E. Ferrin, and P.C. Babbitt, PLoS One 2009, 4, e4345). However, the members of the biological/biomedical community have not had access to the capability to generate SSNs for their "favorite" protein families. In this article we announce the EFI-EST (Enzyme Function Initiative-Enzyme Similarity Tool) web tool (http://efi.igb.illinois.edu/efi-est/) that is available without cost for the automated generation of SSNs by the community. The tool can create SSNs for the "closest neighbors" of a user-supplied protein sequence from the UniProt database (Option A) or of members of any user-supplied Pfam and/or InterPro family (Option B). We provide an introduction to SSNs, a description of EFI-EST, and a demonstration of the use of EFI-EST to explore sequence-function space in the OMP decarboxylase superfamily (PF00215). This article is designed as a tutorial that will allow members of the community to use the EFI-EST web tool for exploring sequence/function space in protein families.


Asunto(s)
Bases de Datos de Proteínas , Orotidina-5'-Fosfato Descarboxilasa/química , Orotidina-5'-Fosfato Descarboxilasa/genética , Análisis de Secuencia de Proteína , Programas Informáticos , Internet
10.
Phys Sportsmed ; 24(8): 74-83, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29283738

RESUMEN

In brief Epistaxis typically originates from the nasal septum when the nasal mucosa overlying a dilated blood vessel is injured. Epistaxis may, however, signal an underlying condition such as a coagulation disorder, so the treating physician must be alert for signs of serious illness. Most nosebleeds stop spontaneously within 5 minutes with or without pressure to the forehead, nose, or upper lip. Some require anterior nasal packing. A few arise from posterior arteries and require anterior-posterior nasal packing and a referral.

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