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1.
Trop Med Infect Dis ; 9(9)2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39330890

RESUMO

West Nile Virus (WNV) poses a significant global public health threat as a mosquito-borne pathogen. While laboratory mouse models have historically played a crucial role in understanding virus biology, recent research has focused on utilizing immunocompromised models to study arboviruses like dengue and Zika viruses, particularly their interactions with Aedes aegypti mosquitoes. However, there has been a shortage of suitable mouse models for investigating WNV and St. Louis encephalitis virus interactions with their primary vectors, Culex spp. mosquitoes. Here, we establish the AG129 mouse (IFN α/ß/γ R-/-) as an effective vertebrate model for examining mosquito-WNV interactions. Following intraperitoneal injection, AG129 mice exhibited transient viremia lasting several days, peaking on the second or third day post-infection, which is sufficient to infect Culex quinquefasciatus mosquitoes during a blood meal. We also observed WNV replication in the midgut and dissemination to other tissues, including the fat body, in infected mosquitoes. Notably, infectious virions were present in the saliva of a viremic AG129 mouse 16 days post-exposure, indicating successful transmission capacity. These findings highlight the utility of AG129 mice for studying vector competence and WNV-mosquito interactions.

2.
Front Med (Lausanne) ; 11: 1400423, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38835799

RESUMO

Hansen's disease, or leprosy, is a disease characterized by dermatological and neurological disorders. A neural form also exists, in which peripheral neuropathy occurs in the absence of skin lesions. However, cases of leprosy that involve the central nervous system and proximal nerves are rare in the literature. We describe the case of an oligosymptomatic patient diagnosed with the neural form of leprosy with involvement of peripheral nerves, dorsal root ganglion, and cervical spinal cord in an atypical presentation of the disease. Through complementary examinations and nerve biopsies, the bacillus was identified, and treatment was subsequently initiated. This case highlights the importance of investigating the suspicion of leprosy, even in cases with atypical manifestations, as early diagnosis and treatment can reduce neurological damage and deformities.

3.
Rev Soc Bras Med Trop ; 57: e004062024, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38808799

RESUMO

BACKGROUND: Musculoskeletal inflammatory lesions in chronic Chikungunya virus (CHIKV) infection have not been thoroughly assessed using whole-body magnetic resonance imaging (WBMRI). This study aimed to determine the prevalence of these lesions in such patients. METHODS: From September 2018 to February 2019, patients with positive Chikungunya-specific serology (Immunoglobulin M/Immunoglobulin G anti-CHIKV), with a history of polyarthralgia for > 6 months prior to MRI with no pre-existing rheumatic disorders, underwent 3T WBMRI and localized MRI. The evaluation focused on musculoskeletal inflammatory lesions correlated with chronic CHIKV infection. Pain levels were assessed using a visual analogue scale on the same day as WBMRI. RESULTS: The study included 86 patients of whom 26 met the inclusion criteria. All patients reported pain and most (92.3%) categorized it as moderate or severe. The most common finding across joints was effusion, particularly in the tibiotalar joint (57.7%) and bursitis, with the retrocalcaneal bursa most affected (48.0%). Tenosynovitis was prevalent in the flexor compartment of the hands (44.2%), while Kager fat pad and soleus edema were also observed. Bone marrow edema-like signals were frequently seen in the sacroiliac joints (19.2%). Most WBMRI findings were classified as mild. CONCLUSIONS: This study represents the first utilization of 3T WBMRI to assess musculoskeletal inflammatory disorders in chronic CHIKV infection. The aim was to identify the most affected joints and prevalent lesions, providing valuable insights for future research and clinical management of this condition regarding understanding disease pathophysiology, developing targeted treatment strategies, and using advanced imaging techniques in the assessment of musculoskeletal manifestations.


Assuntos
Febre de Chikungunya , Imageamento por Ressonância Magnética , Imagem Corporal Total , Humanos , Febre de Chikungunya/complicações , Febre de Chikungunya/diagnóstico por imagem , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Doença Crônica , Idoso , Doenças Musculoesqueléticas/diagnóstico por imagem , Adulto Jovem
4.
Viruses ; 16(4)2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38675917

RESUMO

The incidence of chikungunya has dramatically surged worldwide in recent decades, imposing an expanding burden on public health. In recent years, South America, particularly Brazil, has experienced outbreaks that have ravaged populations following the rapid dissemination of the chikungunya virus (CHIKV), which was first detected in 2014. The primary vector for CHIKV transmission is the urban mosquito species Aedes aegypti, which is highly prevalent throughout Brazil. However, the impact of the locally circulating CHIKV genotypes and specific combinations of local mosquito populations on vector competence remains unexplored. Here, we experimentally analyzed and compared the infectivity and transmissibility of the CHIKV-ECSA lineage recently isolated in Brazil among four Ae. aegypti populations collected from different regions of the country. When exposed to CHIKV-infected AG129 mice for blood feeding, all the mosquito populations displayed high infection rates and dissemination efficiency. Furthermore, we observed that all the populations were highly efficient in transmitting CHIKV to a vertebrate host (naïve AG129 mice) as early as eight days post-infection. These results demonstrate the high capacity of Brazilian Ae. aegypti populations to transmit the locally circulating CHIKV-ECSA lineage. This observation could help to explain the high prevalence of the CHIKV-ECSA lineage over the Asian lineage, which was also detected in Brazil in 2014. However, further studies comparing both lineages are necessary to gain a better understanding of the vector's importance in the epidemiology of CHIKV in the Americas.


Assuntos
Aedes , Febre de Chikungunya , Vírus Chikungunya , Mosquitos Vetores , Animais , Aedes/virologia , Vírus Chikungunya/genética , Vírus Chikungunya/classificação , Vírus Chikungunya/fisiologia , Vírus Chikungunya/isolamento & purificação , Brasil/epidemiologia , Febre de Chikungunya/transmissão , Febre de Chikungunya/virologia , Febre de Chikungunya/epidemiologia , Camundongos , Mosquitos Vetores/virologia , Genótipo , Feminino , Filogenia
5.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;57: e00406, 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1559189

RESUMO

ABSTRACT Background: Musculoskeletal inflammatory lesions in chronic Chikungunya virus (CHIKV) infection have not been thoroughly assessed using whole-body magnetic resonance imaging (WBMRI). This study aimed to determine the prevalence of these lesions in such patients. Methods: From September 2018 to February 2019, patients with positive Chikungunya-specific serology (Immunoglobulin M/Immunoglobulin G anti-CHIKV), with a history of polyarthralgia for > 6 months prior to MRI with no pre-existing rheumatic disorders, underwent 3T WBMRI and localized MRI. The evaluation focused on musculoskeletal inflammatory lesions correlated with chronic CHIKV infection. Pain levels were assessed using a visual analogue scale on the same day as WBMRI. Results: The study included 86 patients of whom 26 met the inclusion criteria. All patients reported pain and most (92.3%) categorized it as moderate or severe. The most common finding across joints was effusion, particularly in the tibiotalar joint (57.7%) and bursitis, with the retrocalcaneal bursa most affected (48.0%). Tenosynovitis was prevalent in the flexor compartment of the hands (44.2%), while Kager fat pad and soleus edema were also observed. Bone marrow edema-like signals were frequently seen in the sacroiliac joints (19.2%). Most WBMRI findings were classified as mild. Conclusions: This study represents the first utilization of 3T WBMRI to assess musculoskeletal inflammatory disorders in chronic CHIKV infection. The aim was to identify the most affected joints and prevalent lesions, providing valuable insights for future research and clinical management of this condition regarding understanding disease pathophysiology, developing targeted treatment strategies, and using advanced imaging techniques in the assessment of musculoskeletal manifestations.

6.
bioRxiv ; 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37961153

RESUMO

The global incidence of chikungunya has surged in recent decades, with South America, particularly Brazil, experiencing devastating outbreaks. The primary vector for transmitting CHIKV in urban areas is the mosquito species Aedes aegypti, which is very abundant in Brazil. However, little is known about the impact of locally circulating CHIKV genotypes and specific combinations of mosquito populations on vector competence. In this study, we analyzed and compared the infectivity and transmissibility of a recently isolated CHIKV-ECSA lineage from Brazil among four Ae. aegypti populations collected from different regions of the country. When exposed to CHIKV-infected mice for blood feeding, all mosquito populations showed high infection rates and dissemination efficiency. Moreover, using a mouse model to assess transmission rates in a manner that better mirrors natural cycles, we observed that these populations exhibit highly efficient transmission rates of CHIKV-ECSA. Our findings underscore the robust capability of Brazilian Ae. aegypti populations to transmit the locally circulating CHIKV-ECSA lineage, potentially explaining its higher prevalence compared to the Asian lineage also introduced in Brazil.

7.
Pathogens ; 11(8)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-36015000

RESUMO

Arboviruses (an acronym for "arthropod-borne virus"), such as dengue, yellow fever, Zika, and Chikungunya, are important human pathogens transmitted by mosquitoes. These viruses impose a growing burden on public health. Despite laboratory mice having been used for decades for understanding the basic biological phenomena of these viruses, it was only recently that researchers started to develop immunocompromised animals to study the pathogenesis of arboviruses and their transmission in a way that parallels natural cycles. Here, we show that the AG129 mouse (IFN α/ß/γ R-/-) is a suitable and comprehensive vertebrate model for studying the mosquito vector competence for the major arboviruses of medical importance, namely the dengue virus (DENV), yellow fever virus (YFV), Zika virus (ZIKV), Mayaro virus (MAYV), and Chikungunya virus (CHIKV). We found that, after intraperitoneal injection, AG129 mice developed a transient viremia lasting several days, peaking on day two or three post infection, for all five arboviruses tested in this study. Furthermore, we found that the observed viremia was ample enough to infect Aedes aegypti during a blood meal from the AG129 infected mice. Finally, we demonstrated that infected mosquitoes could transmit each of the tested arboviruses back to naïve AG129 mice, completing a full transmission cycle of these vector-borne viruses. Together, our data show that A129 mice are a simple and comprehensive vertebrate model for studies of vector competence, as well as investigations into other aspects of mosquito biology that can affect virus-host interactions.

8.
Eur Radiol ; 32(2): 1154-1162, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34363135

RESUMO

OBJECTIVES: To evaluate prospectively the feasibility of magnetic resonance neurography (MRN) in identifying the anatomical characteristics of thenar muscular branch (TMB) of the median nerve, also known as the "million dollar nerve," in patients and controls. METHODS: Thirteen patients affected by carpal tunnel syndrome (CTS) and four healthy controls had their hands scanned on a 3-T MR imaging scanner for TMB visualization. Median nerve anatomical variations were classified into four groups according to Poisel's classification system modified by Lanz. TMB signal intensity and diameter were assessed for the diagnosis of neuropathy. RESULTS: TMB was successfully identified in all patients and subjects by using MRN. The most suitable pulse sequences to identify and measure nerve diameter were 3D DW-PSIF and T2-FS-TSE. The axial oblique and sagittal oblique planes are complementary in demonstrating its entire course. TMB had mostly an extraligamentous course with radial side origin (93.8%, each). All patients experienced increased T2 signal intensity (p < 0.001) and thickened nerves. Mean TMB diameters were 1.27 ± 0.21 mm (range, 1.02-1.74 mm) and 0.87 ± 0.16 mm (0.73-1.08 mm) (p = 0.008) in the patient and control groups, respectively. CONCLUSION: MRN is a reliable imaging technique for identification and anatomical characterization of TMB in patients affected by CTS. This innovative imaging workup may therefore be included in the preoperative evaluation of patients scheduled for carpal tunnel release, especially in CTS with TMB involvement or even in isolated TMB neuropathy. KEY POINTS: • Magnetic resonance neurography allows precise visualization of the thenar muscular branch of the median nerve. • Thenar muscular branch anatomical variations can be correctly identified. • Preoperative scanning can contribute to reducing the risk of iatrogenic injuries during carpal tunnel release, especially in carpal tunnel syndrome with thenar muscular branch involvement or even in isolated thenar muscular branch neuropathy.


Assuntos
Síndrome do Túnel Carpal , Nervo Mediano , Síndrome do Túnel Carpal/diagnóstico por imagem , Mãos , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Nervo Mediano/diagnóstico por imagem
9.
Viruses ; 13(5)2021 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-33923055

RESUMO

The emergence of new human viral pathogens and re-emergence of several diseases are of particular concern in the last decades. Oropouche orthobunyavirus (OROV) is an arbovirus endemic to South and Central America tropical regions, responsible to several epidemic events in the last decades. There is little information regarding the ability of OROV to be transmitted by urban/peri-urban mosquitoes, which has limited the predictability of the emergence of permanent urban transmission cycles. Here, we evaluated the ability of OROV to infect, replicate, and be transmitted by three anthropophilic and urban species of mosquitoes, Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus. We show that OROV is able to infect and efficiently replicate when systemically injected in all three species tested, but not when orally ingested. Moreover, we find that, once OROV replication has occurred in the mosquito body, all three species were able to transmit the virus to immunocompromised mice during blood feeding. These data provide evidence that OROV is restricted by the midgut barrier of three major urban mosquito species, but, if this restriction is overcome, could be efficiently transmitted to vertebrate hosts. This poses a great risk for the emergence of permanent urban cycles and geographic expansion of OROV to other continents.


Assuntos
Aedes/virologia , Culex/virologia , Mosquitos Vetores/virologia , Orthobunyavirus/fisiologia , Animais , Infecções por Bunyaviridae/transmissão , Infecções por Bunyaviridae/virologia , Modelos Animais de Doenças , Feminino , Especificidade de Hospedeiro , Interações Hospedeiro-Patógeno , Camundongos , Camundongos Knockout
10.
Viruses ; 12(8)2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32784948

RESUMO

Mayaro virus (MAYV), a sylvatic arbovirus belonging to the Togaviridae family and Alphavirus genus, is responsible for an increasing number of outbreaks in several countries of Central and South America. Despite Haemagogus janthinomys being identified as the main vector of MAYV, laboratory studies have already demonstrated the competence of Aedes aegypti to transmit MAYV. It has also been demonstrated that the WolbachiawMel strain is able to impair the replication and transmission of MAYV in Ae. aegypti. In Ae. aegypti, the small interfering RNA (siRNA) pathway is an important antiviral mechanism; however, it remains unclear whether siRNA pathway acts against MAYV infection in Ae. aegypti. The main objective of this study was to determine the contribution of the siRNA pathway in the control of MAYV infection. Thus, we silenced the expression of AGO2, an essential component of the siRNA pathway, by injecting dsRNA-targeting AGO2 (dsAGO2). Our results showed that AGO2 is required to control MAYV replication upon oral infection in Wolbachia-free Ae. aegypti. On the other hand, we found that Wolbachia-induced resistance to MAYV in Ae. aegypti is independent of the siRNA pathway. Our study brought new information regarding the mechanism of viral protection, as well as on Wolbachia mediated interference.


Assuntos
Aedes/microbiologia , Aedes/virologia , Alphavirus/genética , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Wolbachia/fisiologia , Aedes/imunologia , Infecções por Alphavirus/imunologia , Infecções por Alphavirus/virologia , Animais , Feminino , Humanos , Imunidade Inata , Mosquitos Vetores/imunologia , Mosquitos Vetores/microbiologia , Mosquitos Vetores/virologia , Wolbachia/imunologia
11.
PLoS Negl Trop Dis ; 14(4): e0007518, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32287269

RESUMO

Newly emerging or re-emerging arthropod-borne viruses (arboviruses) are important causes of human morbidity and mortality worldwide. Arboviruses such as Dengue (DENV), Zika (ZIKV), Chikungunya (CHIKV), and West Nile virus (WNV) have undergone extensive geographic expansion in the tropical and sub-tropical regions of the world. In the Americas the main vectors of DENV, ZIKV, and CHIKV are mosquito species adapted to urban environments, namely Aedes aegypti and Aedes albopictus, whereas the main vector of WNV is Culex quinquefasciatus. Given the widespread distribution in the Americas and high permissiveness to arbovirus infection, these mosquito species may play a key role in the epidemiology of other arboviruses normally associated with sylvatic vectors. Here, we test this hypothesis by determining the vector competence of Ae. aegypti, Ae. albopictus, and Cx. quinquefasciatus to Mayaro (MAYV) virus, a sylvatic arbovirus transmitted mainly by Haemagogus janthinomys that has been causing an increasing number of outbreaks in South America, namely in Brazil. Using field mosquitoes from Brazil, female mosquitoes were experimentally infected, and their competence for infection and transmission rates of MAYV was evaluated. We found consistent infection rate for MAYV in Ae. aegypti (57.5%) and Ae. albopictus (61.6%), whereas very low rates were obtained for Cx. quinquefasciatus (2.5%). Concordantly, we observed high potential transmission ability in Ae. aegypti and Ae. albopictus (69.5% and 71.1% respectively), in contrast to Cx. quinquefasciatus, which could not transmit the MAYV. Notably, we found that very low quantities of virus present in the saliva (undetectable by RT-qPCR) were sufficiently virulent to guarantee transmission. Although Ae. aegypti and Ae. albopictus mosquitoes are not the main vectors for MAYV, our studies suggest that these mosquitoes could play a significant role in the transmission of this arbovirus, since both species showed significant vector competence for MAYV (Genotype D), under laboratory conditions.


Assuntos
Aedes/virologia , Infecções por Alphavirus/virologia , Alphavirus/isolamento & purificação , Culex/virologia , Transmissão de Doença Infecciosa , Alphavirus/genética , Alphavirus/crescimento & desenvolvimento , Infecções por Alphavirus/transmissão , Animais , Brasil , Feminino , Reação em Cadeia da Polimerase em Tempo Real , Saliva/virologia , Carga Viral
15.
Radiol. bras ; Radiol. bras;46(4): 227-233, Jul-Aug/2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-684596

RESUMO

Inferior vena cava anomalies are rare, occurring in up to 8.7% of the population, as left renal vein anomalies are considered. The inferior vena cava develops from the sixth to the eighth gestational weeks, originating from three paired embryonic veins, namely the subcardinal, supracardinal and postcardinal veins. This complex ontogenesis of the inferior vena cava, with multiple anastomoses between the pairs of embryonic veins, leads to a number of anatomic variations in the venous return from the abdomen and lower limbs. Some of such variations have significant clinical and surgical implications related to other cardiovascular anomalies and in some cases associated with venous thrombosis of lower limbs, particularly in young adults. The authors reviewed images of ten patients with inferior vena cava anomalies, three of them with deep venous thrombosis. The authors highlight the major findings of inferior vena cava anomalies at multidetector computed tomography and magnetic resonance imaging, correlating them the embryonic development and demonstrating the main alternative pathways for venous drainage. The knowledge on the inferior vena cava anomalies is critical in the assessment of abdominal images to avoid misdiagnosis and to indicate the possibility of associated anomalies, besides clinical and surgical implications.


Anomalias da veia cava inferior são incomuns, ocorrendo em até 8,7% da população, quando consideradas as anomalias da veia renal esquerda. A veia cava inferior se desenvolve da sexta à oitava semanas de gestação, originada de três veias embrionárias pareadas: veias subcardinais, supracardinais e pós-cardinais. A complexidade da ontogenia da veia cava inferior, com numerosas anastomoses entre essas três veias embrionárias, pode levar a uma grande variedade do retorno venoso do abdome e membros inferiores. Algumas dessas anomalias têm implicações clínicas e cirúrgicas significativas, associadas a outras anomalias congênitas, e em alguns casos, associadas a trombose venosa de membros inferiores, principalmente em pacientes adultos jovens. Foram revistos os exames de dez pacientes com anomalias da veia cava inferior, três deles com trombose venosa profunda de membros inferiores. Foram salientados os principais aspectos das anomalias da veia cava inferior, nos exames de tomografia computadorizada multidetectores e ressonância magnética, correlacionados com a embriologia e demonstrando as principais vias alternativas de drenagem venosa. O conhecimento das anomalias da veia cava inferior é fundamental na avaliação dos exames de imagem do abdome, evitando erros de interpretação e indicando a possibilidade de anomalias associadas, implicações clínicas e cirúrgicas.

16.
Radiol. bras ; Radiol. bras;41(5): 349-351, set.-out. 2008. ilus
Artigo em Inglês, Português | LILACS | ID: lil-496941

RESUMO

Neste trabalho relata-se o caso de uma paciente de 46 anos de idade com queixa de aumento de volume periumbilical e dor leve antes da menstruação. O quadro evoluiu com aumento gradativo da dor. Foram realizados ultra-som, tomografia computadorizada e ressonância magnética. Após laparotomia exploradora, foi retirado material para biópsia que confirmou o diagnóstico de leiomiomatose peritoneal disseminada.


The present study reports the case of a 46-year-old female patient complaining of mild premenstrual pain and increase in the volume of the periumbilical region. The condition progressed with a gradual increase of the pain intensity. Ultrasonography, computed tomography and magnetic resonance imaging were performed. Biopsy of tissue collected during exploratory laparotomy confirmed the diagnosis of leiomyomatosis peritonealis disseminata.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Anticoncepcionais Orais , Leiomiomatose/diagnóstico , Neoplasias Peritoneais , Biópsia , Diagnóstico por Imagem , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X
17.
Hig. aliment ; 16(94): 20-25, mar. 2002. tab, graf
Artigo em Português | LILACS | ID: lil-307831

RESUMO

Tem como objetivo avaliar as condições higiênico-sanitárias de mercados e feiras livres situados na cidade do Recife-PE. O instrumento de avaliação utilizado foi a "Ficha de Inspeção de Estabelecimentos, na +rea de Alimentos" determinada pela Resolução SS-196/98, publicada no Diário Oficial do Estado de São Paulo. Os aspectos considerados incluem condições das instalações, equipamentos e utensílios, pessoal, características dos produtos expostos à venda e práticas de manipulação. Foram detectadas falhas em diversos pontos, levando-se a concluir que as condições atuais de grande parte destes tipos de estabelecimentos destinados à comercialização de gêneros alimentícios são precárias. + notória a necessidade de investimentos e treinamento sobre práticas adequadas para manipulção de alimentos, para comerciantes envolvidos e consumidores, de uma forma geral.


Assuntos
Qualidade de Produtos para o Consumidor , Vigilância Sanitária , Saneamento de Mercados
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