scholarly journals Carbon Nanodots in Photodynamic Antimicrobial Therapy: A Review

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4004 ◽  
Author(s):  
Rachael Knoblauch ◽  
Chris D. Geddes

Antibiotic resistance development in bacteria is an ever-increasing global health concern as new resistant strains and/or resistance mechanisms emerge each day, out-pacing the discovery of novel antibiotics. Increasingly, research focuses on alternate techniques, such as antimicrobial photodynamic therapy (APDT) or photocatalytic disinfection, to combat pathogens even before infection occurs. Small molecule “photosensitizers” have been developed to date for this application, using light energy to inflict damage and death on nearby pathogens via the generation of reactive oxygen species (ROS). These molecular agents are frequently limited in widespread application by synthetic expense and complexity. Carbon dots, or fluorescent, quasi-spherical nanoparticle structures, provide an inexpensive and “green” solution for a new class of APDT photosensitizers. To date, reviews have examined the overall antimicrobial properties of carbon dot structures. Herein we provide a focused review on the recent progress for carbon nanodots in photodynamic disinfection, highlighting select studies of carbon dots as intrinsic photosensitizers, structural tuning strategies for optimization, and their use in hybrid disinfection systems and materials. Limitations and challenges are also discussed, and contemporary experimental strategies presented. This review provides a focused foundation for which APDT using carbon dots may be expanded in future research, ultimately on a global scale.

Crisis ◽  
2020 ◽  
Vol 41 (3) ◽  
pp. 172-178
Author(s):  
Brooke A. Ammerman ◽  
Martha K. Fahlgren ◽  
Kristen M. Sorgi ◽  
Michael S. McCloskey

Abstract. Background: Despite being a major public health concern, it is unclear how suicidal thoughts and behaviors differentially impact separate racial groups. Aims: The aim of the current study was to examine the occurrence of nonlethal suicide events, in addition to suicide attempt characteristics and factors contributing to suicide attempts. Method: A final sample of 7,094 undergraduates from a large northeastern university, identifying as members of three racial groups (White [67.30%], Black [17.30%], and Asian [15.40%]), completed online questionnaires. Results: White participants reported increased likelihood of endorsing lifetime suicidal ideation and plan, whereas Black participants reported decreased likelihood of these events; no differences were found in rates of lifetime suicide attempts. Black participants' suicidal behavior may involve greater ambivalence of intent. A higher proportion of Asian participants endorsed interpersonal factors as contributing to their suicide attempts, whereas a greater percentage of White participants reported internal contributing factors. Limitations: Findings are limited by the sample size and assessment of lifetime suicidal thoughts and behaviors. Conclusion: The findings present a more nuanced look at attitudes and actions related to suicidal thoughts and behaviors that may inform future research and risk assessment procedures.


Author(s):  
Nilushi Indika Bamunu Arachchige ◽  
Fazlurrahman Khan ◽  
Young-Mog Kim

Background: The treatment of infection caused by pathogenic bacteria becomes one of the serious concerns globally. The failure in the treatment was found due to the exhibition of multiple resistance mechanisms against the antimicrobial agents. Emergence of resistant bacterial species has also been observed due to prolong treatment using conventional antibiotics. To combat these problems, several alternative strategies have been employed using biological and chemically synthesized compounds as antibacterial agents. Marine organisms considered as one of the potential sources for the isolation of bioactive compounds due to the easily available, cost-effective, and eco-friendly. Methods: The online search methodology was adapted for the collection of information related to the antimicrobial properties of marine-derived compounds. These compound has been isolated and purified by different purification techniques, and their structure also characterized. Furthermore, the antibacterial activities have been reported by using broth microdilution as well as disc diffusion assays. Results: The present review paper describes the antimicrobial effect of diverse secondary metabolites which are isolated and purified from the different marine organisms. The structural elucidation of each secondary metabolite has also been done in the present paper, which will help for the in silico designing of the novel and potent antimicrobial compounds. Conclusion: A thorough literature search has been made and summarizes the list of antimicrobial compounds that are isolated from both prokaryotic and eukaryotic marine organisms. The information obtained from the present paper will be helpful for the application of marine compounds as antimicrobial agents against different antibiotic-resistant human pathogenic bacteria.


2019 ◽  
Vol 14 (2) ◽  
pp. 146-151 ◽  
Author(s):  
Junaid Khan ◽  
Amit Alexander ◽  
Mukta Agrawal ◽  
Ajazuddin ◽  
Sunil Kumar Dubey ◽  
...  

Diabetes and its complications are a significant health concern throughout the globe. There are physiological differences in the mechanism of type-I and type-II diabetes and the conventional drug therapy as well as insulin administration seem to be insufficient to address the problem at large successfully. Hypoglycemic swings, frequent dose adjustments and resistance to the drug are major problems associated with drug therapy. Cellular approaches through stem cell based therapeutic interventions offer a promising solution to the problem. The need for pancreatic transplants in case of Type- I diabetes can also be by-passed/reduced due to the formation of insulin producing β cells via stem cells. Embryonic Stem Cells (ESCs) and induced Pluripotent Stem Cells (iPSCs), successfully used for generating insulin producing β cells. Although many experiments have shown promising results with stem cells in vitro, their clinical testing still needs more exploration. The review attempts to bring into light the clinical studies favoring the transplantation of stem cells in diabetic patients with an objective of improving insulin secretion and improving degeneration of different tissues in response to diabetes. It also focuses on the problems associated with successful implementation of the technique and possible directions for future research.


2021 ◽  
Vol 34 (1) ◽  
Author(s):  
Micaela Reich ◽  
Lydia P. Buki

AbstractCancer is a leading cause of death worldwide and is expected to remain a public health concern for years to come. Within Latin America, Uruguay has the highest colorectal cancer rates. Heeding past calls to action, in this article we provide a critical assessment of colorectal cancer needs and opportunities in Uruguay with a focus on developing a roadmap for future action. First, we provide an overview of risk factors, screening procedures and guidelines, and screening rates. Next, we provide an overview of psychosocial factors that influence colorectal cancer screening, with the goal of providing guidance for future behavioral health promotion initiatives in Uruguay. In this effort, we present four conceptual models that may be used for interventions: the ecological systems theory, informed decision-making, the health beliefs model, and the health literacy model. Subsequently, we propose using an integrated model based on the ecological systems theory and health literacy model to develop national, local, and community-based interventions to increase screening rates and lower the colorectal cancer burden in Uruguay. We close the paper with a summary and implications section, including recommendations for future research programs focused on the assessment of factors that influence screening.


2021 ◽  
Vol 22 (5) ◽  
pp. 2497
Author(s):  
Filippo Prencipe ◽  
Anna Zanfardino ◽  
Michela Di Napoli ◽  
Filomena Rossi ◽  
Stefano D’Errico ◽  
...  

The evolution of antibacterial resistance has arisen as the main downside in fighting bacterial infections pushing researchers to develop novel, more potent and multimodal alternative drugs.Silver and its complexes have long been used as antimicrobial agents in medicine due to the lack of silver resistance and the effectiveness at low concentration as well as to their low toxicities compared to the most commonly used antibiotics. N-Heterocyclic Carbenes (NHCs) have been extensively employed to coordinate transition metals mainly for catalytic chemistry. However, more recently, NHC ligands have been applied as carrier molecules for metals in anticancer applications. In the present study we selected from literature two NHC-carbene based on acridinescaffoldand detailed nonclassicalpyrazole derived mono NHC-Ag neutral and bis NHC-Ag cationic complexes. Their inhibitor effect on bacterial strains Gram-negative and positivewas evaluated. Imidazolium NHC silver complex containing the acridine chromophore showed effectiveness at extremely low MIC values. Although pyrazole NHC silver complexes are less active than the acridine NHC-silver, they represent the first example of this class of compounds with antimicrobial properties. Moreover all complexesare not toxic and they show not significant activity againstmammalian cells (Hek lines) after 4 and 24 h. Based on our experimental evidence, we are confident that this promising class of complexes could represent a valuable starting point for developing candidates for the treatment of bacterial infections, delivering great effectiveness and avoiding the development of resistance mechanisms.


Viruses ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 891
Author(s):  
Eric Agboli ◽  
Julien B. Z. Zahouli ◽  
Athanase Badolo ◽  
Hanna Jöst

Mosquito-associated viruses (MAVs), including mosquito-specific viruses (MSVs) and mosquito-borne (arbo)viruses (MBVs), are an increasing public, veterinary, and global health concern, and West Africa is projected to be the next front for arboviral diseases. As in-depth knowledge of the ecologies of both western African MAVs and related mosquitoes is still limited, we review available and comprehensive data on their diversity, abundance, and distribution. Data on MAVs’ occurrence and related mosquitoes were extracted from peer-reviewed publications. Data on MSVs, and mosquito and vertebrate host ranges are sparse. However, more data are available on MBVs (i.e., dengue, yellow fever, chikungunya, Zika, and Rift Valley fever viruses), detected in wild and domestic animals, and humans, with infections more concentrated in urban areas and areas affected by strong anthropogenic changes. Aedes aegypti, Culex quinquefasciatus, and Aedes albopictus are incriminated as key arbovirus vectors. These findings outline MAV, related mosquitoes, key knowledge gaps, and future research areas. Additionally, these data highlight the need to increase our understanding of MAVs and their impact on host mosquito ecology, to improve our knowledge of arbovirus transmission, and to develop specific strategies and capacities for arboviral disease surveillance, diagnostic, prevention, control, and outbreak responses in West Africa.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Francisco-Jose Molina-Castillo ◽  
Elfriede Penz ◽  
Barbara Stöttinger

PurposeDemand for fake physical and digital products is a global phenomenon with substantive detrimental effects on companies and consumers. This raises various questions and issues, such as whether there are generalizable explanations of purchase intentions.Design/methodology/approachThis research is based on consumer samples from three different countries. This paper develops and tests a model based on the theory of planned behavior (TPB) to explain both the demand for counterfeits and digital piracy. Respondents were questioned about physical products (e.g. clothing, accessories) from well-known brands and digital products (e.g. software, music).FindingsSocially oriented motives such as embarrassment potential, ethical concerns and social norms explain the intention to purchase fake physical and digital products, while personally oriented motives (e.g. self-identity) have indirect effects but not a direct impact on purchase intention.Research limitations/implicationsAs our results show, we find evidence for a general model – contributing and supporting our first and primary research goal of providing a theoretically robust model that bridges the gap between two streams of literature.Practical implicationsThe fact that drivers of buying counterfeit physical and digital goods are similar across countries provides justification for companies and international organizations to bundle their efforts and thus leverage them more strongly on a global scale.Originality/valueWe provide a basis for consolidating future research on demand for counterfeits and pirated goods because underlying factors driving demand are similar across the three countries studied herein.


SAGE Open ◽  
2017 ◽  
Vol 7 (4) ◽  
pp. 215824401773458 ◽  
Author(s):  
Naim Fanaj ◽  
Erika Melonashi

Mental health problems related to the psychological trauma of war still represent a public health concern in postwar Kosovo. Despite the universal character of exposure to trauma, there are suggestions that the manifestation posttraumatic stress disorder (PTSD) or related psychosocial factors might vary across cultures. The aim of the present article was to provide a critical overview of research on PTSD in the specific sociocultural context of Kosovo by examining prevalence rates, as well as related demographic and psychosocial variables. For this purpose, 51 studies were evaluated. Results showed that, even 10 years postwar prevalence rates for PTSD are still high among civilians exposed to trauma, refugees, and veterans. As regards psychiatric and psychological constructs correlating with PTSD, studies suggested the following: anxiety, depression, suicidal ideation, anger, and revenge thoughts. Moreover, socioeconomic factors and social support were identified as highly influential on quality of life of individuals with PTSD. Nonetheless the studies considered for review had numerous methodological problems such as sample size, self-selection, nonrandomized process, and lack of control groups, findings of existing studies still need to be carefully considered and future research is necessary.


2014 ◽  
Vol 926-930 ◽  
pp. 158-161
Author(s):  
Wan You Zhang ◽  
Sheng Chao Ji ◽  
Hai Feng Zhang ◽  
Xi Xin Zhang

Membrane bioreactor (MBR) has developed rapidly in recent years; however, the membrane fouling problems are affecting its further widespread application. This paper discusses the role of metal ions in the mixture in the mechanism; also on the high-priced metal ions coexist in the mixture when the effects of biological flocculation process; finally, the direction of future research in this area are summarized.


10.2196/20158 ◽  
2020 ◽  
Vol 22 (12) ◽  
pp. e20158
Author(s):  
Dylan Gilbey ◽  
Helen Morgan ◽  
Ashleigh Lin ◽  
Yael Perry

Background Young people (aged 12-25 years) with diverse sexuality, gender, or bodily characteristics, such as those who identify as lesbian, gay, bisexual, transgender, intersex, or queer (LGBTIQ+), are at substantially greater risk of a range of mental, physical, and sexual health difficulties compared with their peers. Digital health interventions have been identified as a potential way to reduce these health disparities. Objective This review aims to summarize the characteristics of existing evidence-based digital health interventions for LGBTIQ+ young people and to describe the evidence for their effectiveness, acceptability, and feasibility. Methods A systematic literature search was conducted using internet databases and gray literature sources, and the results were screened for inclusion. The included studies were synthesized qualitatively. Results The search identified 38 studies of 24 unique interventions seeking to address mental, physical, or sexual health–related concerns in LGBTIQ+ young people. Substantially more evidence-based interventions existed for gay and bisexual men than for any other population group, and there were more interventions related to risk reduction of sexually transmitted infections than to any other health concern. There was some evidence for the effectiveness, feasibility, and acceptability of these interventions overall; however, the quality of evidence is often lacking. Conclusions There is sufficient evidence to suggest that targeted digital health interventions are an important focus for future research aimed at addressing health difficulties in LGBTIQ+ young people. Additional digital health interventions are needed for a wider range of health difficulties, particularly in terms of mental and physical health concerns, as well as more targeted interventions for same gender–attracted women, trans and gender-diverse people, and people with intersex variations. Trial Registration PROSPERO International Prospective Register of Systematic Reviews CRD42020128164; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=128164


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