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Characterization of protease cleavage sites involved in the formation of the envelope glycoprotein and three non-structural proteins of dengue virus type 2, New Guinea C strain.

Amino terminal sequences of the envelope protein E and the three largest nonstructural proteins NS1, NS3, and NS5 of the New Guinea C strain of dengue virus type 2 (DEN-2) were obtained by nucleotide and protein sequencing. Clones were prepared containing cDNA of DEN-2 virus in the plasmid pUC8. The nucleotide sequences of viral cDNA inserts were determined and the cDNA of each clone positioned on the flavivirus genomic map by comparison of the deduced amino acid sequence with that of yellow fever virus. Radiolabelled E, NS1, NS3 and NS5 were purified by lectin affinity chromatography and prep…

Partial nucleotide sequence of St. Louis encephalitis virus RNA: structural proteins, NS1, ns2a, and ns2b.

cDNA clones of the St. Louis encephalitis (SLE) virus genome have been obtained and the nucleotide sequence of 4.7 kb corresponding to the 5' terminal half of the genome determined. The genome contains a 5' noncoding region of 98 nucleotides followed by a single continuous open reading frame that encodes three structural proteins in the order capsid (C), membrane precursor (prM)-membrane (M), and envelope (E). Immediately following the C-terminus of E are located nonstructural proteins NS1 through NS3. The SLE amino acid sequence homology with yellow fever (YF), Murray Valley encephalitis (MVE…

Предварительная изоляция противомоскитного фактора.

Натриуретический фактор, вызывающий диурез в изолированных мальпигских трубках комаров, был изолирован от головы желтотопливного комара Эйдеса аегипти путем прохождения солевого экстракта голов комаров через колонны низкого давления и затем высокого давления жидкой хроматографии (HPLC). Три фракции с биологической активностью исчезли во время обратной фазы линейного градиента ацетонитриля HPLC. Фракция I деполяризовала трансэпителевское напряжение (Vt) изолированных перфюзных мальпигских тубулей, но не стимулировала секрецию жидкости в эссее (Дж. А. Рамси, Джей. Эксп. Биол. 31: 104-113, 1954 г

Seroepidemiologic studies in Oaxaca, Mexico. II. Survey for arbovirus antibody.

A serologic survey was conducted in south-western Mexico to obtain information on human experience with arbovirus infections. Sera were coll … cent were positive with St. Louis encephalitis (SLE), 19 per cent with Ilhéus, and 4 per cent with yellow fever viruses. The pattern of reactions suggested that SLE or an antigenically related virus was responsible for the antibody detected. An unusually high rate was found in a mountain area at 2,000 meters: 41 per cent of 113 persons tested were seropositiv …

The Use of Disabled Insecticidal Proteins (DIPs) to Investigate the Interaction Between Aedes aegypti-Active Toxins from Bacillus thuringiensis.

A variety of pesticidal proteins derived from the bacterium Bacillus thuringiensis exhibit activity against the yellow fever mosquito Aedes aegypti and are used to control this insect vector. Several of these proteins, including Cry1Ca and Cry2Aa, additionally have activity against lepidopteran insects. Furthermore, the specificity of Cry2Aa has recently been shown to depend on domain I of the Cry protein, whereas it is generally recognized that domain II is the primary specificity-determining domain. This work has made use of disabled forms of three Cry proteins (Cry2Aa, Cry1Ca and Cry11Aa) a…

The co-infection of pulmonary hydatid cyst, lophomoniasis and tuberculosis in a patient with resistant respiratory symptoms; a case report study.

BACKGROUND: Lophomonas blattarum is a rare protozoan that causes opportunistic infections, and the co-infection of lophomonas with tuberculosis and human hydatidosis is a serious public problem in the co-endemic areas of developing countries. CASE REPORT: We presented a 58-year-old female with fever, losing weight, and cough with whitish-yellow sputum that started one month ago. Increasing inflammatory markers and hypereosinophilia in laboratory tests, and a cavity with thick, regular walls and undulating air-fluid levels measuring 43 × 30, evident in the upper segment of the right lower lobe

The spread of Aedes albopictus (Diptera: Culicidae) in the islands of São Tomé and Príncipe.

The mosquito Aedes albopictus (Diptera: Culicidae) is a vector species of the causal agents of Dengue, yellow fever, and Zika among other diseases pathogens. The species originated in Southeast Asia and has spread widely and rapidly in the last century. The species has been reported in localities from the Gulf of Guinea since the early 2000s, but systematic sampling has been scant. We sampled Ae. albopictus twice, in 2013 and 2023 across the altitudinal gradient in São Tomé and found that the species was present in all sampled years at altitudes up to 680 m. We also found some evidence of incr…

Chemical control of medically important arthropods in Panama: A systematic literature review of historical efforts.

Vector-borne diseases are a major source of morbidity in Panama. Herein, we describe historical usage patterns of synthetic insecticides to control arthropod disease vectors in this country. We examine the influence of interventions by vector control programs on the emergence of insecticide resistance. Chemical control has traditionally focused on two mosquito species: Anopheles albimanus, a major regional malaria vector, and Aedes aegypti, a historical vector of yellow fever, and current vector of dengue, chikungunya, and Zika. Countrywide populations of An. albimanus depict hyperirritability…

Timeliness for vaccination according to the expanded immunization program in children under 6 years of age in Colombia between 2014 and 2019.

The aim was to estimate the vaccination timeliness defined as the proportion of children under 6 years of age who received their immunizatio … f the country. More than 80% of children had a timeliness to get most vaccines. The exceptions were yellow fever (17%) and seasonal influenza (42%). No differences in timeliness were found according to geographic region or by health system affiliation regime, but the average timeliness for all vaccines of children of the indigenous population (65.8% ±18.4%) wa …

Dissection of Mosquito Ovaries, Midgut, and Salivary Glands for Microbiome Analyses at the Organ Level.

The global burden of mosquito-transmitted diseases, including malaria, dengue, West Nile, Zika, Usutu, and yellow fever, continues to increase, posing a significant public health threat. With the rise of insecticide resistance and the absence of effective vaccines, new strategies are emerging that focus on the mosquito's microbiota. Nevertheless, the majority of symbionts remain resistant to cultivation. Characterizing the diversity and function of bacterial genomes in mosquito specimens, therefore, relies on metagenomics and subsequent assembly and binning strategies. The obtention and analys…

Preparation of β-Myrcene-Chitosan Nanoparticles and Their Uptake and Toxicity in Aedes aegypti Larvae.

Mosquito control still relies heavily on synthetic molecules, which can lead to the selection of resistant populations and undesirable environmental problems. This study described the preparation of a nanoparticle of the plant-derived molecule, β-myrcene, with chitosan, and the assessment of its toxicity against larvae of the yellow fever mosquito, Aedes aegypti. By producing fluorescent chitosan nanoparticles, we were able to observe their distribution in the digestive tract of larvae of Ae. aegypti. Chitosan-based nanoparticles containing β-myrcene (238 mg/L) could kill 100% of the larvae te…

Membrane fusion by dengue virus: The first step.

Flaviviruses include important human pathogens such as Dengue, Zika, West Nile, Yellow fever, Japanese encephalitis, and Tick-borne encephalitis viruses as well as some emerging viruses that affect millions of people worldwide. They fuse their membrane with the late endosomal one in a pH-dependent way and therefore the merging of the membranes is one of the main goals for obtaining new antivirals. The envelope E protein, a membrane fusion protein, is accountable for fusion and encompasses different domains involved in the fusion mechanism, including the fusion peptide segment. In this work we …

Vector-Transmitted Flaviviruses: An Antiviral Molecules Overview.

Flaviviruses cause numerous pathologies in humans across a broad clinical spectrum with potentially severe clinical manifestations, including hemorrhagic and neurological disorders. Among human flaviviruses, some viral proteins show high conservation and are good candidates as targets for drug design. From an epidemiological point of view, flaviviruses cause more than 400 million cases of infection worldwide each year. In particular, the Yellow Fever, dengue, West Nile, and Zika viruses have high morbidity and mortality-about an estimated 20,000 deaths per year. As they depend on human vectors…

Cellulose Hydrogels Containing Geraniol and Icaridin Encapsulated in Zein Nanoparticles for Arbovirus Control.

The most important arboviruses are those that cause dengue, yellow fever, chikungunya, and Zika, for which the main vector is the Aedes aegypti mosquito. The use of repellents is an important way to combat mosquito-borne pathogens. In this work, a safe method of protection employing a repellent was developed based on a slow release system composed of zein nanoparticles containing the active agents icaridin and geraniol incorporated in a cellulose gel matrix. Analyses were performed to characterize the nanoparticles and the gel formulation. The nanoparticles containing the repellents presented …

An immunologist's guide to immunosenescence and its treatment.

INTRODUCTION: Aging causes several changes in the immune system, although immune aging is strongly influenced by individual immunological history, as well as genetic and environmental factors leading to inter-individual variability. AREAS COVERED: We focused on the biological and clinical meaning of immunosenescence. SARS-CoV-2 and Yellow Fever vaccine have demonstrated the clinical relevance of immunosenescence, while inconsistent results, obtained from longitudinal studies aimed at looking for immune risk phenotypes, have revealed that immunosenescence is highly context-dependent. Large pro…

The Lazarette of Jurujuba in the nineteenth-century Rio de Janeiro press: "a better place to spread fishing nets than to found such an establishment".

In the second half of the nineteenth century, the press expanded and reached a wide range of themes and audiences. It consisted of daily newspapers, which were especially dedicated to the daily life of the city, and scientific-literary magazines, which published texts on a wide range of themes, including literature, biography, science, and education. In the pages of the numerous periodicals that circulated around Rio de Janeiro, both the so-called daily newspapers and the scientific-literary periodicals, there was a great interest in the themes of hygiene, salubrity, the yellow fever epidemic,…

Chryseobacterium indologenes Ventilator-Associated Pneumonia in an Elderly Patient: A Case Report.

Chryseobacterium indologenes is a rare non-fermenting gram-negative pathogen that can cause opportunistic infections in humans. Most infections are nosocomial and acquired through contaminated devices such as ventilators, endotracheal tubes, and indwelling catheters. An increasing number of infections have been reported in recent years after the first reported case of ventilator-associated pneumonia in 1993. Blood, lung, ocular, and peritoneal infections, among others, have been reported. The high rate of intrinsic resistance to broad-spectrum antibiotics is a matter of concern since there are

Вакцинация пациентов с множественным склерозом в эпоху COVID-19: Новости о безопасности вакцин и иммуногенности.

Множественный склероз (MS) — неизлечимое аутоиммунное заболевание, которое, как известно, вызывает широко распространенные демиелионирующие повреждения в центральной нервной системе (CNS) и множество изнурительных симптомов у пациентов. Считается, что развитие MS обусловлено разрушением мозгового барьера в крови, последующим проникновением CD4+ и CD8+T клеток, а также широкомасштабным воспалением и обезвоживанием CNS. Болезни, изменяющие терапию (ДМТ), серьезно нарушают эти процессы и, следовательно, составляют один из важнейших компонентов борьбы с заболеваниями. Однако воздействие этих терап

Совпадение в аннотации оригинала
Multiple sclerosis (MS) is an incurable autoimmune disease known to cause widespread demyelinating lesions in the central nervous system (CN … irus disease 2019 (COVID-19) pandemic. Discussed in this review are vaccinations against influenza, yellow fever, human papillomavirus, measles, mumps, rubella, Streptococcus pneumoniae, hepatitis B, and COVID-19. This article additionally reviews our current understanding of COVID-19 severity and incidence in this patient population, the risks and benefits of …

Two Haplotypes of Aedes aegypti Detected by ND4 Mitochondrial Marker in Three Regions of Ecuador.

Aedes aegypti, also known as the yellow fever mosquito, is the main vector of several arboviruses. In Ecuador, dengue and chikungunya are the most prevalent mosquito-borne diseases. Hence, there is a need to understand the population dynamics and genetic structure of the vector in tropical areas for a better approach towards effective vector control programs. This study aimed to assess the genetic diversity of Ae. aegypti, through the analyses of the mitochondrial gene ND4, using a combination of phylogenetic and population genetic structure from 17 sites in Ecuador. Results showed two haploty…

Ecological Effects on the Dynamics of West Nile Virus and Avian Plasmodium: The Importance of Mosquito Communities and Landscape.

Humans and wildlife are at risk from certain vector-borne diseases such as malaria, dengue, and West Nile and yellow fevers. Factors linked to global change, including habitat alteration, land-use intensification, the spread of alien species, and climate change, are operating on a global scale and affect both the incidence and distribution of many vector-borne diseases. Hence, understanding the drivers that regulate the transmission of pathogens in the wild is of great importance for ecological, evolutionary, health, and economic reasons. In this literature review, we discuss the ecological fa…