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1.
Malar J ; 23(1): 156, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38773487

RESUMO

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.


Assuntos
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/métodos
2.
Malar J ; 22(1): 384, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129897

RESUMO

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.


Assuntos
Culicidae , Tecnologia de Impulso Genético , Malária , Animais , Humanos , Tecnologia de Impulso Genético/métodos , África Subsaariana , Governo , Malária/prevenção & controle
3.
Schmerz ; 2023 Jul 05.
Artigo em Alemão | MEDLINE | ID: mdl-37405523

RESUMO

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.

4.
Int J Cancer ; 146(2): 449-460, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31584195

RESUMO

Bladder cancer is the sixth most common cancer in the United States, and it exhibits an alarming 70% recurrence rate. Thus, the development of more efficient antibladder cancer approaches is a high priority. Accordingly, this work provides the basis for a transformative anticancer strategy that takes advantage of the unique characteristics of the bladder. Unlike mucin-shielded normal bladder cells, cancer cells are exposed to the bladder lumen and overexpress EGFR. Therefore, we used an EGF-conjugated anthrax toxin that after targeting EGFR was internalized and triggered apoptosis in exposed bladder cancer cells. This unique agent presented advantages over other EGF-based technologies and other toxin-derivatives. In contrast to known agents, this EGF-toxin conjugate promoted its own uptake via receptor microclustering even in the presence of Her2 and induced cell death with a LC50 < 1 nM. Furthermore, our data showed that exposures as short as ≈3 min were enough to commit human (T24), mouse (MB49) and canine (primary) bladder cancer cells to apoptosis. Exposure of tumor-free mice and dogs with the agent resulted in no toxicity. In addition, the EGF-toxin was able to eliminate cells from human patient tumor samples. Importantly, the administration of EGF-toxin to dogs with spontaneous bladder cancer, who had failed or were not eligible for other therapies, resulted in ~30% average tumor reduction after one treatment cycle. Because of its in vitro and in vivo high efficiency, fast action (reducing treatment time from hours to minutes) and safety, we propose that this EGF-anthrax toxin conjugate provides the basis for new, transformative approaches against bladder cancer.


Assuntos
Antígenos de Bactérias/administração & dosagem , Antineoplásicos/administração & dosagem , Toxinas Bacterianas/administração & dosagem , Fator de Crescimento Epidérmico/administração & dosagem , Imunotoxinas/administração & dosagem , Neoplasias da Bexiga Urinária/tratamento farmacológico , Administração Intravesical , Animais , Antígenos de Bactérias/efeitos adversos , Antineoplásicos/efeitos adversos , Apoptose/efeitos dos fármacos , Toxinas Bacterianas/efeitos adversos , Linhagem Celular Tumoral , Cães , Ensaios de Seleção de Medicamentos Antitumorais , Fator de Crescimento Epidérmico/efeitos adversos , Feminino , Humanos , Imunotoxinas/efeitos adversos , Masculino , Camundongos , Cultura Primária de Células , Receptor ErbB-2/metabolismo , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/veterinária
5.
Chembiochem ; 21(19): 2772-2776, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32369652

RESUMO

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 in 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.


Assuntos
Antígenos de Bactérias/metabolismo , Toxinas Bacterianas/metabolismo , Antígeno Carcinoembrionário/metabolismo , Endopeptidases/metabolismo , Neoplasias Pancreáticas/metabolismo , Antígenos de Bactérias/genética , Toxinas Bacterianas/genética , Citosol/metabolismo , Receptores ErbB/metabolismo , Humanos , Modelos Moleculares , Neoplasias Pancreáticas/patologia
8.
9.
Gates Open Res ; 8: 14, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39035848

RESUMO

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.


Assuntos
Tecnologia de Impulso Genético , Humanos , Tecnologia de Impulso Genético/métodos , Pesquisa Biomédica/ética
11.
Eur J Epidemiol ; 28(5): 373-81, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23385658

RESUMO

Data on seasonal differences in stroke incidence are conflicting. Little is known about seasonal variability in etiological stroke subtypes and population-based data on possible trigger factors are lacking. The Ludwigshafen Stroke Study is a prospective population-based stroke registry. All residents of the city of Ludwigshafen who suffer from acute stroke or TIA are registered. Patients with first-ever stroke (FES) were included for the present analysis. Between January 1, 2006 and December 31st, 2010, 1,779 patients (age 71.7 ± 13.4 years (mean + standard deviation; 897 (50.4 %) women) suffered a FES. Incidence for FES was lowest in summer (reference) with significantly higher rates in winter (rate ratio (RR) 1.20, 95 % confidence interval (CI) 1.05-1.37) and spring (RR 1.21 95 % CI 1.06-1.38). First-ever ischemic stroke (FEIS) was more common in winter (RR 1.16, 95 %CI 1.01-1.34) and first-ever intracerebral haemorrhage (FE-ICH) was more frequent in spring (RR 2.0, 95 %CI 1.24-3.22) than in summer. In FES, systolic and diastolic blood pressure on admission (SBP/DBP) showed significant variation with lowest values in summer (SBP: p = 0.02; DBP p = 0.05). In subtypes of FEIS, cardioembolism tended to be more common in winter (p = 0.14). There were no differences in risk factor prevalence between seasons. Leukocyte count on admission was lowest in summer (8.2 ± 1.4/µl) and highest in winter (8.9 ± 1.9/µl; p = 0.008). The hematocrit showed a similar trend (p = 0.06). Our data show higher incidence rates for FES in winter and spring, for FEIS in winter and for FE-ICH in spring. Variations in blood pressure on admission and leukocyte counts were associated with these findings and may possibly contribute to seasonal stroke variability.


Assuntos
Biomarcadores/análise , Hemorragia Cerebral/etiologia , Ataque Isquêmico Transitório/etiologia , Estações do Ano , Acidente Vascular Cerebral/etiologia , Idoso de 80 Anos ou mais , Proteína C-Reativa/metabolismo , Hemorragia Cerebral/epidemiologia , Feminino , Alemanha/epidemiologia , Hematócrito/estatística & dados numéricos , Humanos , Incidência , Ataque Isquêmico Transitório/epidemiologia , Contagem de Leucócitos/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Prevalência , Sistema de Registros , Análise de Regressão , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia
13.
Beilstein J Org Chem ; 9: 2387-94, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24367404

RESUMO

Functionalized 3-trifluoromethyl-2-isoxazolines and 3-trifluoromethylisoxazoles were easily prepared from trifluoromethyl aldoxime 2 under mild conditions by using DIB as oxidant. Theoretical studies of the reactivity of trifluoroacetonitrile oxide 4 toward olefins and alkynes were carried out. The 3-trifluoromethyl-2-isoxazolines were ring-opened with NaBH4 and NiCl2 to yield the corresponding trifluoromethylated γ-amino alcohols.

14.
Trop Med Infect Dis ; 8(4)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37104327

RESUMO

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.

15.
Asian Pac J Cancer Prev ; 24(7): 2253-2258, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37505754

RESUMO

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.


Assuntos
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 C
19.
BMJ Case Rep ; 15(4)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35473700

RESUMO

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.


Assuntos
COVID-19 , Adulto , COVID-19/complicações , Criança , Humanos , SARS-CoV-2 , Síndrome de Resposta Inflamatória Sistêmica
20.
R I Med J (2013) ; 105(6): 28-31, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35881996

RESUMO

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.


Assuntos
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 imagem
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