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Gene drive technology has been recognized for its potential to provide durable and cost-effective solutions for previously intractable problems in public health, conservation, and agriculture. In recognition of the rapid advances in this field, in 2016 the U.S. National Academies of Sciences, Engineering, and Medicine issued a report making several recommendations aimed at researchers, funders, and policymakers for the safe and responsible research and development of gene drive technology. Subsequently, in 2017 sixteen global organizations self-identifying as sponsors and supporters of gene drive research became public signatories committed to the 'Principles for Gene Drive Research' which were inspired by the report's recommendations. Herein we reflect on the progress of gene drive research in relation to the ethical principles laid out and committed to by the signatories to the Principles. Our analysis indicates high levels of alignment with the Principles in the field of gene drive research. The manuscript also discusses the Gene Drive Research Forum, which had its genesis in the publication of the Principles. Discussions between participants at the latest meeting of the Forum point to the work that lies ahead for gene drive research in line with the Principles. Going forward the gene drive research community can productively focus on: i) safety and efficacy criteria for open release, ii) risk assessment frameworks and methods, iii) more downstream technical, regulatory and policy considerations for field evaluations and implementation, iv) continued transparency and developing mechanisms of accountability, and v) strengthening capacity in locales of potential release and expected drive spread.
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Tecnologia de Impulso Genético , Humanos , Tecnologia de Impulso Genético/métodos , Pesquisa Biomédica/éticaRESUMO
Sustainable reductions in African malaria transmission require innovative tools for mosquito control. One proposal involves the use of low-threshold gene drive in Anopheles vector species, where a 'causal pathway' would be initiated by (i) the release of a gene drive system in target mosquito vector species, leading to (ii) its transmission to subsequent generations, (iii) its increase in frequency and spread in target mosquito populations, (iv) its simultaneous propagation of a linked genetic trait aimed at reducing vectorial capacity for Plasmodium, and (v) reduced vectorial capacity for parasites in target mosquito populations as the gene drive system reaches fixation in target mosquito populations, causing (vi) decreased malaria incidence and prevalence. Here the scope, objectives, trial design elements, and approaches to monitoring for initial field releases of such gene dive systems are considered, informed by the successful implementation of field trials of biological control agents, as well as other vector control tools, including insecticides, Wolbachia, larvicides, and attractive-toxic sugar bait systems. Specific research questions to be addressed in initial gene drive field trials are identified, and adaptive trial design is explored as a potentially constructive and flexible approach to facilitate testing of the causal pathway. A fundamental question for decision-makers for the first field trials will be whether there should be a selective focus on earlier points of the pathway, such as genetic efficacy via measurement of the increase in frequency and spread of the gene drive system in target populations, or on wider interrogation of the entire pathway including entomological and epidemiological efficacy. How and when epidemiological efficacy will eventually be assessed will be an essential consideration before decisions on any field trial protocols are finalized and implemented, regardless of whether initial field trials focus exclusively on the measurement of genetic efficacy, or on broader aspects of the causal pathway. Statistical and modelling tools are currently under active development and will inform such decisions on initial trial design, locations, and endpoints. Collectively, the considerations here advance the realization of developer ambitions for the first field trials of low-threshold gene drive for malaria vector control within the next 5 years.
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Anopheles , Tecnologia de Impulso Genético , Malária , Controle de Mosquitos , Mosquitos Vetores , Controle de Mosquitos/métodos , Mosquitos Vetores/genética , Malária/prevenção & controle , Malária/transmissão , Animais , Anopheles/genética , Tecnologia de Impulso Genético/métodosRESUMO
BACKGROUND: Gene drive modified mosquitoes (GDMMs) have the potential to address Africa's persistent malaria problem, but are still in early stages of development and testing. Continuous engagement of African stakeholders is crucial for successful evaluation and implementation of these technologies. The aim of this multi-country study was, therefore, to explore the insights and recommendations of key stakeholders across Africa on the potential of GDMMs for malaria control and elimination in the continent. METHODS: A concurrent mixed-methods study design was used, involving a structured survey administered to 180 stakeholders in 25 countries in sub-Saharan Africa, followed by 18 in-depth discussions with selected groups and individuals. Stakeholders were drawn from academia, research and regulatory institutions, government ministries of health and environment, media and advocacy groups. Thematic content analysis was used to identify key topics from the in-depth discussions, and descriptive analysis was done to summarize information from the survey data. RESULTS: Despite high levels of awareness of GDMMs among the stakeholders (76.7%), there was a relatively low-level of understanding of their key attributes and potential for malaria control (28.3%). When more information about GDMMs was provided to the stakeholders, they readily discussed their insights and concerns, and offered several recommendations to ensure successful research and implementation of the technology. These included: (i) increasing relevant technical expertise within Africa, (ii) generating local evidence on safety, applicability, and effectiveness of GDMMs, and (iii) developing country-specific regulations for safe and effective governance of GDMMs. A majority of the respondents (92.9%) stated that they would support field trials or implementation of GDMMs in their respective countries. This study also identified significant misconceptions regarding the phase of GDMM testing in Africa, as several participants incorrectly asserted that GDMMs were already present in Africa, either within laboratories or released into the field. CONCLUSION: Incorporating views and recommendations of African stakeholders in the ongoing research and development of GDMMs is crucial for instilling stakeholder confidence on their potential application. These findings will enable improved planning for GDMMs in Africa as well as improved target product profiles for the technologies to maximize their potential for solving Africa's enduring malaria challenge.
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Culicidae , Tecnologia de Impulso Genético , Malária , Animais , Humanos , Tecnologia de Impulso Genético/métodos , África Subsaariana , Governo , Malária/prevenção & controleRESUMO
BACKGROUND: The antitumor activity of Citrus microcarpa B. on HT29 human colon adenocarcinoma tumors xenografted in immunosuppressed mice was determined in this study. OBJECTIVE: The objective of the study was to determine if the crude extract of C. microcarpa B. exhibited antitumor activity against HT29 human colon adenocarcinoma tumors xenografted in immunosuppressed mice. METHODS: Cyclosporine-induced immunosuppressed mice were injected subcutaneously with 106 HT29 cells in the caudo-dorsal area of the back near the base of the tail to induce tumor growth. Tumors were grown for 9 days, and the mice were then administered with C. microcarpa B. (160 and 630 mg/kg) (Group A; n = 4 and B; n = 4) and normal saline solution (Group C; n = 4) intraperitoneally. Tumor volume was measured to assess the change in tumor volume after 24, 48, and 72-hour post-treatment administration. Tumors were then excised and analyzed histopathologically to evaluate the ratio of necrotic area to viable cancer cells in the tumors. RESULTS: Treatment of C. microcarpa B. with a dose of 160 mg/kg (P=0.002) and 630 mg/kg produced a significant decrease in tumor volume with the significance only observed at 72 hours post-treatment. Histopathological analysis showed a considerable decrease in the area of necrosis against viable tumor cells in the treatment of C. microcarpa B. with a dose of 630 mg/kg. CONCLUSION: It can thus be said that C. microcarpa B. is effective in reducing tumor volume, specifically at a dose of 630 mg/kg 72-hours post-treatment.
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Adenocarcinoma , Citrus , Neoplasias do Colo , Humanos , Animais , Camundongos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Adenocarcinoma/tratamento farmacológico , Células HT29 , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Endogâmicos BALB CRESUMO
BACKGROUND: Retropharyngeal calcific tendinitis is an aseptic inflammation of the longus cervicis muscle. This rare acute pain disorder of the neck region is a prognostically benign condition compared to neurological or otorhinolaryngological differential diagnoses. OBJECTIVE: To capture the clinical appearance, diagnostics, treatment and course of this rare disease. MATERIAL AND METHODS: In this retrospective monocentric observational study, demographic, clinical, paraclinical as well as treatment and follow-up data of all inpatients with a diagnosis of retropharyngeal calcific tendinitis admitted to the Diako Hospital Mannheim in the years 2018 to 2021 were analyzed. RESULTS: This study included four female and one male patient with an age between 36 years and 77 years. Severe neck pain with restriction of cervical spine rotation was the leading clinical appearance, in four out of five patients there was a painful swallowing disorder. Inflammatory markers were elevated in four patients. Characteristic MRI or CT imaging alterations of the cervical spine confirmed the diagnosis. The symptoms resolved within 4-14 days after treatment with nonsteroidal anti-inflammatory drugs (NSAID) and four patients additionally received glucocorticoids. No recurrences were observed during the follow-up period of 5-30 months. CONCLUSION: The good prognosis of this rare disease is reflected by the rapid remission of symptoms under NSAIDs and glucocorticoids and by the absence of recurrences during follow-up. CT or MRI imaging is required to rule out differential diagnoses, and to confirm the characteristic imaging alterations of retropharyngeal calcific tendinitis. Additionally, cerebrospinal fluid puncture and otorhinolaryngological assessment may be necessary in some cases.
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Malaria remains an ongoing public health challenge, with over 600,000 deaths in 2021, of which approximately 96% occurred in Africa. Despite concerted efforts, the goal of global malaria elimination has stalled in recent years. This has resulted in widespread calls for new control methods. Genetic biocontrol approaches, including those focused on gene-drive-modified mosquitoes (GDMMs), aim to prevent malaria transmission by either reducing the population size of malaria-transmitting mosquitoes or making the mosquitoes less competent to transmit the malaria parasite. The development of both strategies has advanced considerably in recent years, with successful field trials of several biocontrol methods employing live mosquito products and demonstration of the efficacy of GDMMs in insectary-based studies. Live mosquito biocontrol products aim to achieve area-wide control with characteristics that differ substantially from current insecticide-based vector control methods, resulting in some different considerations for approval and implementation. The successful field application of current biocontrol technologies against other pests provides evidence for the promise of these approaches and insights into the development pathway for new malaria control agents. The status of technical development as well as current thinking on the implementation requirements for genetic biocontrol approaches are reviewed, and remaining challenges for public health application in malaria prevention are discussed.
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Investment, collaboration, and coordination have been key.
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Pesquisa Biomédica , COVID-19 , Humanos , Pesquisa Biomédica/economia , Pesquisa Biomédica/tendências , COVID-19/prevenção & controle , COVID-19/terapia , National Institutes of Health (U.S.) , Investimentos em Saúde , Cooperação Internacional , Vacinas contra COVID-19 , Ensaios Clínicos como AssuntoRESUMO
Isolated angioedema of the small intestine is a rare adverse event in patients taking angiotensin-converting enzyme inhibitors. Here, we present a case of visceral angioedema in a 32-year-old woman who presented with left upper quadrant pain, nausea, vomiting, diarrhea, and characteristic radiographic signs of small bowel angio-edema, six months after starting lisinopril. Her symptoms improved within 48 hours of withholding the offending agent and with supportive care. We discuss the epidemiology, pathophysiology, diagnosis, and management of angiotensin-converting enzyme inhibitor- induced angioedema.
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Angioedema , Inibidores da Enzima Conversora de Angiotensina , Dor Abdominal , Adulto , Angioedema/induzido quimicamente , Angioedema/diagnóstico por imagem , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Antivirais , Diarreia , Feminino , Humanos , Intestino Delgado/diagnóstico por imagemRESUMO
Levamisole is a common adulterant of cocaine and has been associated with reversible leukoencephalopathy in cocaine users. We report a case of two episodes with severe neurological symptoms and multifocal white matter lesions with brainstem and cerebellar involvement in a 29-year-old man after sporadic cocaine consumption. A urinalysis was positive for levamisole. Neurological deficits as well as MRI presentation improved after cessation of levamisole exposure and two courses of intravenous high-dose glucocorticoid therapy. Early diagnosis of levamisole-induced multifocal leukoencephalopathy and treatment with corticosteroids without delay is essential for a good recovery from neurological symptoms. Although cocaine is one of the most prevalent abused illicit drugs, cocaine- and levamisole-induced multifocal leukoencephalopathy is underdiagnosed as this disorder is not often described in the literature and anamnesis of drug abuse is not admitted by the patient. Therefore, an additional screening for cocaine and levamisole in clinical practice is useful in similar cases to support the diagnosis.
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The ability of SARS-CoV-2 to trigger hyperinflammatory response in children and adults is increasingly recognised. However, the detailed features that distinguish severe COVID-19-associated hyperinflammation from multisystem inflammatory syndrome in adults (MIS-A) is not yet known. We describe a young, vaccinated patient with no prior SARS-CoV-2 exposure who developed COVID-19 and MIS-A. We also provide a review of the current literature on MIS-A and COVID-19-associated hyperinflammation.
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COVID-19 , Adulto , COVID-19/complicações , Criança , Humanos , SARS-CoV-2 , Síndrome de Resposta Inflamatória SistêmicaRESUMO
Chronic constipation and fecal impaction are common in older individuals but can also be found in younger patients with cognitive and psychiatric illnesses. The diagnosis of fecal impaction and, the assessment of severity are best performed clinically. Here, we present a case of a 30-year-old autistic individual where limited history was obtainable and further imaging helped to urgently diagnose a 47 x 15.6 x 12 cm stool ball, causing significant mass effect of surrounding intra-abdominal structures. Fecal disimpaction and aggressive bowel regimen prevented the pathological effects of severe fecal retention.
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Impacção Fecal , Adulto , Idoso , Constipação Intestinal/etiologia , Impacção Fecal/diagnóstico por imagem , HumanosRESUMO
Detection and characterization of a different type of topological excitations, namely the domain wall (DW) skyrmion, has received increasing attention because the DW is ubiquitous from condensed matter to particle physics and cosmology. Here we present experimental evidence for the DW skyrmion as the ground state stabilized by long-range Coulomb interactions in a quantum Hall ferromagnet. We develop an alternative approach using nonlocal resistance measurements together with a local NMR probe to measure the effect of low current-induced dynamic nuclear polarization and thus to characterize the DW under equilibrium conditions. The dependence of nuclear spin relaxation in the DW on temperature, filling factor, quasiparticle localization, and effective magnetic fields allows us to interpret this ground state and its possible phase transitions in terms of Wigner solids of the DW skyrmion. These results demonstrate the importance of studying the intrinsic properties of quantum states that has been largely overlooked.
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A type-II InAs/AlAs[Formula: see text]Sb[Formula: see text] multiple-quantum well sample is investigated for the photoexcited carrier dynamics as a function of excitation photon energy and lattice temperature. Time-resolved measurements are performed using a near-infrared pump pulse, with photon energies near to and above the band gap, probed with a terahertz probe pulse. The transient terahertz absorption is characterized by a multi-rise, multi-decay function that captures long-lived decay times and a metastable state for an excess-photon energy of [Formula: see text] meV. For sufficient excess-photon energy, excitation of the metastable state is followed by a transition to the long-lived states. Excitation dependence of the long-lived states map onto a nearly-direct band gap ([Formula: see text]) density of states with an Urbach tail below [Formula: see text]. As temperature increases, the long-lived decay times increase [Formula: see text], due to the increased phonon interaction of the unintentional defect states, and by phonon stabilization of the hot carriers [Formula: see text]. Additionally, Auger (and/or trap-assisted Auger) scattering above the onset of the plateau may also contribute to longer hot-carrier lifetimes. Meanwhile, the initial decay component shows strong dependence on excitation energy and temperature, reflecting the complicated initial transfer of energy between valence-band and defect states, indicating methods to further prolong hot carriers for technological applications.
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Rapid development of an efficacious vaccine against the viral pathogen severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the cause of the coronavirus disease 2019 (COVID-19) pandemic, is essential, but rigorous studies are required to determine the safety of candidate vaccines. Here, on behalf of the Accelerating COVID-19 Therapeutic Interventions and Vaccines (ACTIV) Working Group, we evaluate research on the potential risk of immune enhancement of disease by vaccines and viral infections, including coronavirus infections, together with emerging data about COVID-19 disease. Vaccine-associated enhanced disease has been rarely encountered with existing vaccines or viral infections. Although animal models of SARS-CoV-2 infection may elucidate mechanisms of immune protection, we need observations of enhanced disease in people receiving candidate COVID-19 vaccines to understand the risk of immune enhancement of disease. Neither principles of immunity nor preclinical studies provide a basis for prioritizing among the COVID-19 vaccine candidates with respect to safety at this time. Rigorous clinical trial design and postlicensure surveillance should provide a reliable strategy to identify adverse events, including the potential for enhanced severity of COVID-19 disease, after vaccination.
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Infecções por Coronavirus/imunologia , Pneumonia Viral/imunologia , Vacinas Virais/efeitos adversos , Vacinas Virais/imunologia , Animais , COVID-19 , Vacinas contra COVID-19 , Ensaios Clínicos como Assunto , Infecções por Coronavirus/prevenção & controle , Modelos Animais de Doenças , Desenvolvimento de Medicamentos , Humanos , Pandemias , VacinaçãoRESUMO
The nontoxic, anthrax protective antigen/lethal factor N-terminal domain (PA/LFN ) complex is an effective platform for translocating proteins into the cytosol of cells. Mutant PA (mPA) was recently fused to epidermal growth factor (EGF) to retarget delivery of LFN to cells bearing EGF receptors (EGFR), but the requirement for a known cognate ligand limits the applicability of this approach. Here, we render practical protective antigen retargeting to a variety of receptors with mPA single-chain variable fragment (scFv) fusion constructs. Our design enables the targeting of two pancreatic cancer-relevant receptors, EGFR and carcinoembryonic antigen. We demonstrate that fusion to scFvs does not disturb the basic functions of mPA. Moreover, mPA-scFv fusions enable cell-specific delivery of diphtheria toxin catalytic domain and Ras/Rap1-specific endopeptidase to pancreatic cancer cells. Importantly, mPA-scFv fusion-based treatments display potent cell-specific toxicity inâ vitro, opening fundamentally new routes toward engineered immunotoxins and providing a potential solution to the challenge of targeted protein delivery to the cytosol of cancer cells.