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1.
Heliyon ; 10(11): e32054, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38867966

RESUMO

Questions: The challenges faced by healthcare organizations require effective leaders. Leadership has been extensively studied in medicine and nursing, but it is limited in physiotherapy. The objective of this study is to know and analyze the published research on the characteristics of leadership in physiotherapy. Design: A scoping review was conducted following the PRISMA extension guidelines. MEDLINE, The Cochrane Library, PEDro, Embase, CINAHL, Web Of Science and Scopus databases were reviewed between 01/01/2000 and 30/06/2022.All quantitative studies addressing the characteristics of leadership in physiotherapy were selected. Data extraction was performed using a table including author, year of publication, country of origin, title, objective, measurement instrument, sample and main findings. Data synthesis: The results obtained were framed within the framework for the study of leadership designed by Bolman and Deal. Results: Eight studies were selected. The characteristics most valued or used by physiotherapists are communication, desire for continuous learning and improvement, credibility and professionalism. Conclusion: Leadership is very important for physiotherapists, and for physiotherapy, as profession they consider it very important to have vision and to lead change. Communication skills are the most highly regarded characteristic.

2.
Sci Rep ; 14(1): 10022, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693278

RESUMO

Analyze the gender stereotypes present in the leaders of the Hospital Physiotherapy Units, determine the level of acceptance of female leadership and identify which factors influence these perceptions. Observational, descriptive, exploratory and cross-sectional study. The study subjects are the census of leaders of the Physiotherapy Units of public hospitals. The measurement instruments used are the Acceptance of Female Leadership Questionnaire (ACT-LM), and the sociodemographic and job-related variables. Most of the leaders of the hospital physiotherapy units were women (69.4%) physiotherapists. Gender stereotypes emerge in the dimension of Instrumental Characteristics, with respondents not fully agreeing that women were sufficiently competitive (18.7%) or ambitious (20.8%) to be successful in the world of work. These data were influenced by gender, showing that men have a higher regard for female leadership abilities than women themselves. In the dimension of Acceptance of Female Leadership, 17.4% of those surveyed did not fully agree that women can rise to the same extent as men. Most of the leaders of the physiotherapy units in public hospitals in Spain are women, this is reversed in favor of men in highly complex hospitals. The stereotype persists, especially among women, that they do not have enough ambition and competitiveness to succeed in the world of work.


Assuntos
Liderança , Humanos , Feminino , Masculino , Estudos Transversais , Adulto , Inquéritos e Questionários , Pessoa de Meia-Idade , Fisioterapeutas/psicologia , Hospitais Públicos , Espanha , Estereotipagem , Fatores Sexuais
3.
Eur Arch Otorhinolaryngol ; 280(9): 4205-4214, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37280380

RESUMO

BACKGROUND: The submandibular gland (SMG) is routinely excised during neck dissection. Given the importance of the SMG in saliva production, it is important to understand its involvement rate by cancer tissue and the feasibility of its preservation. METHODS: Retrospective data were collected from five academic centers in Europe. The study involved adult patients affected by primary oral cavity carcinoma (OCC) undergoing tumor excision and neck dissection. The main outcome analyzed was the SMG involvement rate. A systematic review and a meta-analysis were also conducted to provide an updated synthesis of the topic. RESULTS: A total of 642 patients were enrolled. The SMG involvement rate was 12/642 (1.9%; 95% CI 1.0-3.2) when considered per patient, and 12/852 (1.4%; 95% CI 0.6-2.1) when considered per gland. All the glands involved were ipsilateral to the tumor. Statistical analysis showed that predictive factors for gland invasion were: advanced pT status, advanced nodal involvement, presence of extracapsular spread and perivascular invasion. The involvement of level I lymph nodes was associated with gland invasion in 9 out of 12 cases. pN0 cases were correlated with a reduced risk of SMG involvement. The review of the literature and the meta-analysis confirmed the rare involvement of the SMG: on the 4458 patients and 5037 glands analyzed, the involvement rate was 1.8% (99% CI 1.1-2.7) and 1.6% (99% CI 1.0-2.4), respectively. CONCLUSIONS: The incidence of SMG involvement in primary OCC is rare. Therefore, exploring gland preservation as an option in selected cases would be reasonable. Future prospective studies are needed to investigate the oncological safety and the real impact on quality of life of SMG preservation.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Adulto , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Glândula Submandibular/cirurgia , Estudos Retrospectivos , Qualidade de Vida , Neoplasias Bucais/cirurgia , Neoplasias Bucais/patologia , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/patologia , Esvaziamento Cervical , Neoplasias de Cabeça e Pescoço/patologia , Estudos Multicêntricos como Assunto
4.
Healthcare (Basel) ; 11(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37174877

RESUMO

BACKGROUND: Many stroke survivors suffer from sensorimotor deficits, especially balance impairments. The purpose of this trial is to investigate whether the designed Immersive Virtual Reality training program is better in the short term (15 sessions) and in the medium term (30 sessions) than physiotherapy training with Bayouk, Boucher and Leroux exercises, with respect to static balance in sitting and standing, dynamic balance and quality of life in patients with balance impairment in stroke survivors. METHODS: This study is a randomized controlled trial with two treatment arms and evaluators blinded, and a functionality treatment group in combination with specific balance exercise training according to Bayouk, Boucher and Leroux (control group) or a balanced treatment using Immersive VR. The primary outcome will be static, Dynamic balance and gait measured by Bestest Assessment Score (BESTest), Berg Scale (BBS), Pass Scale (PASS) and Time Up and Go test (TUG). The secondary outcome will be the stroke-associated quality of life using the Stroke Quality of Life Scale (ECVI-38). CONCLUSIONS: The results of this study may add new insights into how to address balance using Immersive Virtual Reality after a stroke. If the new training approach proves effective, the results may provide insight into how to design more comprehensive protocols in the future for people with balance impairments after stroke.

5.
PLoS Pathog ; 19(3): e1011269, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36996244

RESUMO

Trypanosoma brucei spp. develop into mammalian-infectious metacyclic trypomastigotes inside tsetse salivary glands. Besides acquiring a variant surface glycoprotein (VSG) coat, little is known about the metacyclic expression of invariant surface antigens. Proteomic analyses of saliva from T. brucei-infected tsetse flies identified, in addition to VSG and Brucei Alanine-Rich Protein (BARP) peptides, a family of glycosylphosphatidylinositol (GPI)-anchored surface proteins herein named as Metacyclic Invariant Surface Proteins (MISP) because of its predominant expression on the surface of metacyclic trypomastigotes. The MISP family is encoded by five paralog genes with >80% protein identity, which are exclusively expressed by salivary gland stages of the parasite and peak in metacyclic stage, as shown by confocal microscopy and immuno-high resolution scanning electron microscopy. Crystallographic analysis of a MISP isoform (MISP360) and a high confidence model of BARP revealed a triple helical bundle architecture commonly found in other trypanosome surface proteins. Molecular modelling combined with live fluorescent microscopy suggests that MISP N-termini are potentially extended above the metacyclic VSG coat, and thus could be tested as a transmission-blocking vaccine target. However, vaccination with recombinant MISP360 isoform did not protect mice against a T. brucei infectious tsetse bite. Lastly, both CRISPR-Cas9-driven knock out and RNAi knock down of all MISP paralogues suggest they are not essential for parasite development in the tsetse vector. We suggest MISP may be relevant during trypanosome transmission or establishment in the vertebrate's skin.


Assuntos
Parasitos , Trypanosoma brucei brucei , Trypanosoma , Animais , Camundongos , Trypanosoma brucei brucei/genética , Proteínas de Membrana , Alanina , Proteômica , Glândulas Salivares/parasitologia , Mamíferos , Glicoproteínas de Membrana
6.
PLoS Negl Trop Dis ; 16(9): e0010791, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36129968

RESUMO

Trypanosoma vivax is a unicellular hemoparasite, and a principal cause of animal African trypanosomiasis (AAT), a vector-borne and potentially fatal livestock disease across sub-Saharan Africa. Previously, we identified diverse T. vivax-specific genes that were predicted to encode cell surface proteins. Here, we examine the immune responses of naturally and experimentally infected hosts to these unique parasite antigens, to identify immunogens that could become vaccine candidates. Immunoprofiling of host serum shows that one particular family (Fam34) elicits a consistent IgG antibody response. This gene family, which we now call Vivaxin, encodes at least 124 transmembrane glycoproteins that display quite distinct expression profiles and patterns of genetic variation. We focused on one gene (viv-ß8) that encodes one particularly immunogenic vivaxin protein and which is highly expressed during infections but displays minimal polymorphism across the parasite population. Vaccination of mice with VIVß8 adjuvanted with Quil-A elicits a strong, balanced immune response and delays parasite proliferation in some animals but, ultimately, it does not prevent disease. Although VIVß8 is localized across the cell body and flagellar membrane, live immunostaining indicates that VIVß8 is largely inaccessible to antibody in vivo. However, our phylogenetic analysis shows that vivaxin includes other antigens shown recently to induce immunity against T. vivax. Thus, the introduction of vivaxin represents an important advance in our understanding of the T. vivax cell surface. Besides being a source of proven and promising vaccine antigens, the gene family is clearly an important component of the parasite glycocalyx, with potential to influence host-parasite interactions.


Assuntos
Trypanosoma vivax , Vacinas , Animais , Formação de Anticorpos , Antígenos de Protozoários/genética , Imunoglobulina G/genética , Camundongos , Filogenia , Trypanosoma vivax/genética , Glicoproteínas Variantes de Superfície de Trypanosoma/genética
7.
mBio ; 13(1): e0235721, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35012336

RESUMO

The single-celled parasite Trypanosoma brucei is transmitted by hematophagous tsetse flies. Life cycle progression from mammalian bloodstream form to tsetse midgut form and, subsequently, infective salivary gland form depends on complex developmental steps and migration within different fly tissues. As the parasite colonizes the glucose-poor insect midgut, ATP production is thought to depend on activation of mitochondrial amino acid catabolism via oxidative phosphorylation (OXPHOS). This process involves respiratory chain complexes and F1Fo-ATP synthase and requires protein subunits of these complexes that are encoded in the parasite's mitochondrial DNA (kDNA). Here, we show that progressive loss of kDNA-encoded functions correlates with a decreasing ability to initiate and complete development in the tsetse. First, parasites with a mutated F1Fo-ATP synthase with reduced capacity for OXPHOS can initiate differentiation from bloodstream to insect form, but they are unable to proliferate in vitro. Unexpectedly, these cells can still colonize the tsetse midgut. However, these parasites exhibit a motility defect and are severely impaired in colonizing or migrating to subsequent tsetse tissues. Second, parasites with a fully disrupted F1Fo-ATP synthase complex that is completely unable to produce ATP by OXPHOS can still differentiate to the first insect stage in vitro but die within a few days and cannot establish a midgut infection in vivo. Third, parasites lacking kDNA entirely can initiate differentiation but die soon after. Together, these scenarios suggest that efficient ATP production via OXPHOS is not essential for initial colonization of the tsetse vector but is required to power trypanosome migration within the fly. IMPORTANCE African trypanosomes cause disease in humans and their livestock and are transmitted by tsetse flies. The insect ingests these parasites with its blood meal, but to be transmitted to another mammal, the trypanosome must undergo complex development within the tsetse fly and migrate from the insect's gut to its salivary glands. Crucially, the parasite must switch from a sugar-based diet while in the mammal to a diet based primarily on amino acids when it develops in the insect. Here, we show that efficient energy production by an organelle called the mitochondrion is critical for the trypanosome's ability to swim and to migrate through the tsetse fly. Surprisingly, trypanosomes with impaired mitochondrial energy production are only mildly compromised in their ability to colonize the tsetse fly midgut. Our study adds a new perspective to the emerging view that infection of tsetse flies by trypanosomes is more complex than previously thought.


Assuntos
Parasitos , Trypanosoma brucei brucei , Trypanosoma , Tripanossomíase Africana , Moscas Tsé-Tsé , Animais , Humanos , Trypanosoma brucei brucei/genética , Moscas Tsé-Tsé/parasitologia , Parasitos/genética , DNA de Cinetoplasto/metabolismo , Fosforilação Oxidativa , Tripanossomíase Africana/parasitologia , Trypanosoma/metabolismo , Mamíferos/metabolismo
8.
J Clin Med ; 10(19)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34640491

RESUMO

(1) Background: The development of new technologies means that the use of virtual reality is increasingly being implemented in rehabilitative approaches for adult stroke patients. OBJECTIVE: To analyze the existing scientific evidence regarding the application of immersive and non-immersive virtual reality in patients following cerebrovascular incidents and their efficacy in achieving dynamic and static balance. (2) Data sources: An electronic search of the databases Medline, Cochrane Library, PEDro, Scopus, and Scielo from January 2010 to December 2020 was carried out using the terms physiotherapy, physical therapy, virtual reality, immersive virtual reality, non-immersive virtual reality, stroke, balance, static balance, and dynamic balance. SELECTION OF STUDIES: Randomized controlled trials in patients older than 18 developed with an adult population (>18 years old) with balance disorders as a consequence of suffering a stroke in the previous six months before therapeutic intervention, including exercises harnessing virtual reality in their interventions and evaluations of balance and published in English or Spanish, were included. A total of two hundred twenty-seven articles were found, ten of which were included for review and of these, nine were included in the subsequent meta-analysis. (3) Data extraction: Two authors selected the studies and extracted their characteristics (participants, interventions, and validation instruments) and results. The methodological quality of the studies was evaluated using the PEDro scale, and the risk of bias was determined using the Cochrane risk-of-bias tool. DATA SYNTHESIS: Of the selected studies, three did not show significant improvements and seven showed significant improvements in the intervention groups in relation to the variables. (4) Conclusions: Non-immersive virtual reality combined with conventional rehabilitation could be considered as a therapeutic option.

9.
Stem Cells ; 39(10): 1310-1321, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34152044

RESUMO

As one of the primary points of entry of xenobiotic substances and infectious agents into the body, the lungs are subject to a range of dysfunctions and diseases that together account for a significant number of patient deaths. In view of this, there is an outstanding need for in vitro systems in which to assess the impact of both infectious agents and xenobiotic substances of the lungs. To address this issue, we have developed a protocol to generate airway epithelial basal-like cells from induced pluripotent stem cells, which simplifies the manufacture of cellular models of the human upper airways. Basal-like cells generated in this study were cultured on transwell inserts to allow formation of a confluent monolayer and then exposed to an air-liquid interface to induce differentiation into a pseudostratified epithelial construct with a marked similarity to the upper airway epithelium in vivo. These constructs contain the component cell types required of an epithelial model system, produce mucus and functional cilia, and can support SARS-CoV-2 infection/replication and the secretion of cytokines in a manner similar to that of in vivo airways. This method offers a readily accessible and highly scalable protocol for the manufacture of upper airway models that could find applications in development of therapies for respiratory viral infections and the assessment of drug toxicity on the human lungs.


Assuntos
COVID-19/patologia , COVID-19/virologia , Células-Tronco Pluripotentes Induzidas/patologia , Pulmão/patologia , Pulmão/virologia , Modelos Biológicos , SARS-CoV-2/fisiologia , Linhagem Celular , Citocinas/metabolismo , Células Epiteliais/patologia , Células Epiteliais/virologia , Humanos , Mediadores da Inflamação/metabolismo , Replicação Viral/fisiologia
10.
PLoS Biol ; 19(1): e3000796, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33497373

RESUMO

Tsetse transmit African trypanosomiasis, which is a disease fatal to both humans and animals. A vaccine to protect against this disease does not exist so transmission control relies on eliminating tsetse populations. Although neurotoxic insecticides are the gold standard for insect control, they negatively impact the environment and reduce populations of insect pollinator species. Here we present a promising, environment-friendly alternative to current insecticides that targets the insect tyrosine metabolism pathway. A bloodmeal contains high levels of tyrosine, which is toxic to haematophagous insects if it is not degraded and eliminated. RNA interference (RNAi) of either the first two enzymes in the tyrosine degradation pathway (tyrosine aminotransferase (TAT) and 4-hydroxyphenylpyruvate dioxygenase (HPPD)) was lethal to tsetse. Furthermore, nitisinone (NTBC), an FDA-approved tyrosine catabolism inhibitor, killed tsetse regardless if the drug was orally or topically applied. However, oral administration of NTBC to bumblebees did not affect their survival. Using a novel mathematical model, we show that NTBC could reduce the transmission of African trypanosomiasis in sub-Saharan Africa, thus accelerating current disease elimination programmes.


Assuntos
Cicloexanonas/uso terapêutico , Reposicionamento de Medicamentos , Controle de Infecções/métodos , Nitrobenzoatos/uso terapêutico , Tripanossomíase Africana/prevenção & controle , 4-Hidroxifenilpiruvato Dioxigenase/antagonistas & inibidores , 4-Hidroxifenilpiruvato Dioxigenase/metabolismo , Animais , Abelhas/efeitos dos fármacos , Feminino , Humanos , Inseticidas/uso terapêutico , Masculino , Metaboloma/efeitos dos fármacos , Camundongos , Modelos Teóricos , Doenças Negligenciadas/prevenção & controle , Produção de Droga sem Interesse Comercial , Ratos , Ratos Wistar , Testes de Toxicidade , Tripanossomíase Africana/transmissão , Moscas Tsé-Tsé/efeitos dos fármacos , Moscas Tsé-Tsé/metabolismo , Tirosina/metabolismo
11.
mBio ; 13(1): e0371821, 2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35164559

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) extensively N-glycosylates its spike proteins, which are necessary for host cell invasion and the target of both vaccines and immunotherapies. These N-glycans are predicted to modulate spike binding to the host receptor by stabilizing its open conformation and host immunity evasion. Here, we investigated the essentiality of both the host N-glycosylation pathway and SARS-CoV-2 N-glycans for infection. Ablation of host N-glycosylation using RNA interference or inhibitors, including FDA-approved drugs, reduced the spread of the infection, including that of variants B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma) and B.1.617.2 (Delta). Under these conditions, cells produced fewer virions and some completely lost their infectivity. Furthermore, partial enzymatic deglycosylation of intact virions showed that surface-exposed N-glycans are critical for cell invasion. Altogether, we propose protein N-glycosylation as a targetable pathway with clinical potential for treatment of COVID-19. IMPORTANCE The coronavirus SARS-CoV-2 uses its spike surface proteins to infect human cells. Spike proteins are heavily modified with several N-glycans, which are predicted to modulate their function. In this work, we show that interfering with either the synthesis or attachment of spike N-glycans significantly reduces the spread of SARS-CoV-2 infection in vitro, including that of several variants. As new SARS-CoV-2 variants, with various degrees of resistance against current vaccines, are likely to continue appearing, halting virus glycosylation using repurposed human drugs could result in a complementary strategy to reducing the spread of COVID-19 worldwide.


Assuntos
COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , COVID-19/metabolismo , COVID-19/prevenção & controle , Glicosilação , Polissacarídeos/metabolismo , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
12.
J Infect Dis ; 222(9): 1462-1467, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32798217

RESUMO

The scientific community has responded to the coronavirus disease 2019 (COVID-19) pandemic by rapidly undertaking research to find effective strategies to reduce the burden of this disease. Encouragingly, researchers from a diverse array of fields are collectively working towards this goal. Research with infectious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is undertaken in high-containment laboratories; however, it is often desirable to work with samples at lower-containment levels. To facilitate the transfer of infectious samples from high-containment laboratories, we have tested methods commonly used to inactivate virus and prepare the sample for additional experiments. Incubation at 80°C, a range of detergents, Trizol reagents, and UV energies were successful at inactivating a high titer of SARS-CoV-2. Methanol and paraformaldehyde incubation of infected cells also inactivated the virus. These protocols can provide a framework for in-house inactivation of SARS-CoV-2 in other laboratories, ensuring the safe use of samples in lower-containment levels.


Assuntos
Betacoronavirus/crescimento & desenvolvimento , Inativação de Vírus , Animais , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/efeitos da radiação , Bioensaio , Pesquisa Biomédica , Chlorocebus aethiops , Detergentes , Formaldeído , Guanidinas , Temperatura Alta , Metanol , Fenóis , Polímeros , SARS-CoV-2 , Raios Ultravioleta , Células Vero , Ensaio de Placa Viral
13.
bioRxiv ; 2020 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-32511399

RESUMO

The scientific community has responded to the COVID-19 pandemic by rapidly undertaking research to find effective strategies to reduce the burden of this disease. Encouragingly, researchers from a diverse array of fields are collectively working towards this goal. Research with infectious SARS-CoV-2 is undertaken in high containment laboratories, however, it is often desirable to work with samples at lower containment levels. To facilitate the transfer of infectious samples from high containment laboratories, we have tested methods commonly used to inactivate virus and prepare the sample for additional experiments. Incubation at 80°C, and a range of detergents and UV energies were successful at inactivating a high titre of SARS-CoV-2. These protocols can provide a framework for in house inactivation of SARS-CoV-2 in other laboratories, ensuring the safe use of samples in lower containment levels.

14.
Nat Microbiol ; 5(7): 909-916, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32313202

RESUMO

The peritrophic matrix of blood-feeding insects is a chitinous structure that forms a protective barrier against oral pathogens and abrasive particles1. Tsetse flies transmit Trypanosoma brucei, which is the parasite that causes human sleeping sickness and is also partially responsible for animal trypanosomiasis in Sub-Saharan Africa. For this parasite to establish an infection in flies, it must first colonize the area between the peritrophic matrix and gut epithelium called the ectoperitrophic space. Although unproven, it is generally accepted that trypanosomes reach the ectoperitrophic space by penetrating the peritrophic matrix in the anterior midgut2-4. Here, we revisited this event using fluorescence- and electron-microscopy methodologies. We show that trypanosomes penetrate the ectoperitrophic space in which the newly made peritrophic matrix is synthesized by the proventriculus. Our model describes how these proventriculus-colonizing parasites can either migrate to the ectoperitrophic space or become trapped within peritrophic matrix layers to form cyst-like bodies that are passively pushed along the gut as the matrix gets remodelled. Furthermore, early proventricular colonization seems to be promoted by factors in trypanosome-infected blood that cause higher salivary gland infections and potentially increase parasite transmission.


Assuntos
Proventrículo/parasitologia , Trypanosoma brucei brucei/fisiologia , Moscas Tsé-Tsé/microbiologia , Animais , Proventrículo/ultraestrutura , Trypanosoma brucei brucei/isolamento & purificação , Moscas Tsé-Tsé/ultraestrutura
15.
PLoS Negl Trop Dis ; 13(10): e0007712, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31626654

RESUMO

BACKGROUND: Phlebotomus (Larroussius) guggisbergi is among the confirmed vectors for cutaneous leishmaniasis (CL) transmission in Kenya. This scarring and stigmatizing form of leishmaniasis accounts for over one million annual cases worldwide. Most recent CL epidemics in Kenya have been reported in Gilgil, Nakuru County, where the disease has become a public health issue. However, little is known about the factors that drive its transmission. Here, we sought to determine the occurrence, distribution and host blood feeding preference of the vectors, and to identify Leishmania species and infection rates in sandflies using molecular techniques. This information could lead to a better understanding of the disease transmission and improvement of control strategies in the area. METHODOLOGY/ PRINCIPAL FINDINGS: An entomological survey of sandflies using CDC light traps was conducted for one week per month in April 2016, and in June and July 2017 from five villages of Gilgil, Nakuru county; Jaica, Sogonoi, Utut, Gitare and Njeru. Sandflies were identified to species level using morphological keys and further verified by PCR analysis of cytochrome c oxidase subunit I (COI) gene. Midguts of female sandflies found to harbour Leishmania were ruptured and the isolated parasites cultured in Novy-MacNeal-Nicolle (NNN) media overlaid with Schneider's insect media to identify the species. Leishmania parasite screening and identification in 198 randomly selected Phlebotomus females and parasite cultures was done by PCR-RFLP analysis of ITS1 gene, nested kDNA-PCR and real-time PCR-HRM followed by sequencing. Bloodmeal source identification was done by real-time PCR-HRM of the vertebrate cytochrome-b gene. A total of 729 sandflies (males: n = 310; females: n = 419) were collected from Utut (36.6%), Jaica (24.3%), Sogonoi (34.4%), Njeru (4.5%), and Gitare (0.1%). These were found to consist of nine species: three Phlebotomus spp. and six Sergentomyia spp. Ph. guggisbergi was the most abundant species (75.4%, n = 550) followed by Ph. saevus sensu lato (11.3%, n = 82). Sandfly species distribution across the villages was found to be significantly different (p<0.001) with Jaica recording the highest diversity. The overall Leishmania infection rate in sandflies was estimated at 7.07% (14/198). Infection rates in Ph. guggisbergi and Ph. saevus s.l. were 9.09% (12/132) and 3.57% (2/56) respectively. L. tropica was found to be the predominant parasite in Gilgil with an overall infection rate of 6.91% (13/188) in Ph. guggisbergi (n = 11) and Ph. saevus s.l. (n = 2) sandflies. However, PCR analysis also revealed L. major infection in one Ph. guggisbergi specimen. Bloodmeal analysis in the 74 blood-fed sandflies disclosed a diverse range of vertebrate hosts in Ph. guggisbergi bloodmeals, while Ph. saevus s.l. fed mainly on humans. CONCLUSIONS/ SIGNIFICANCE: The high infection rates of L. tropica and abundance of Ph. guggisbergi in this study confirms this sandfly as a vector of L. tropica in Kenya. Furthermore, isolation of live L. tropica parasites from Ph. saevus s.l. suggest that there are at least three potential vectors of this parasite species in Gilgil; Ph. guggisbergi, Ph. aculeatus and Ph. saevus s.l. Molecular identification of L. major infections in Ph. guggisbergi suggested this sandfly species as a potential permissive vector of L. major, which needs to be investigated further. Sandfly host preference analysis revealed the possibility of zoonotic transmissions of L. tropica in Gilgil since the main vector (Ph. guggisbergi) does not feed exclusively on humans but also other vertebrate species. Further investigations are needed to determine the potential role of these vertebrate species in L. tropica and L. major transmission in the area.


Assuntos
Leishmania major/fisiologia , Leishmania tropica/fisiologia , Leishmaniose Cutânea/transmissão , Phlebotomus/parasitologia , Psychodidae/parasitologia , Animais , Entomologia , Feminino , Humanos , Quênia/epidemiologia , Leishmaniose Cutânea/epidemiologia , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
16.
Sensors (Basel) ; 19(16)2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31434324

RESUMO

The advent of the Internet of Things (IoT) has led to embedding wireless transceivers into a wide range of devices, in order to implement context-aware scenarios, in which a massive amount of transceivers is foreseen. In this framework, cost-effective electronic and Radio Frequency (RF) front-end integration is desirable, in order to enable straightforward inclusion of communication capabilities within objects and devices in general. In this work, flexible antenna prototypes, based on screen-printing techniques, with conductive inks on flexible low-cost plastic substrates is proposed. Different parameters such as substrate/ink characteristics are considered, as well as variations in fabrication process or substrate angular deflection in device performance. Simulation and measurement results are presented, as well as system validation results in a real test environment in wireless sensor network communications. The results show the feasibility of using screen-printing antenna elements on flexible low-cost substrates, which can be embedded in a wide array of IoT scenarios.

17.
Parasitology ; 146(14): 1773-1784, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31190665

RESUMO

Filarial nematodes possess glutathione transferases (GSTs), ubiquitous enzymes with the potential to detoxify xenobiotic and endogenous substrates, and modulate the host immune system, which may aid worm infection establishment, maintenance and survival in the host. Here we have identified and characterized a σ class glycosylated GST (OoGST1), from the cattle-infective filarial nematode Onchocerca ochengi, which is homologous (99% amino acid identity) with an immunodominant GST and potential vaccine candidate from the human parasite, O. volvulus, (OvGST1b). Onchocerca ochengi native GSTs were purified using a two-step affinity chromatography approach, resolved by 2D and 1D SDS-PAGE and subjected to enzymic deglycosylation revealing the existence of at least four glycoforms. A combination of lectin-blotting and mass spectrometry (MS) analyses of the released N-glycans indicated that OoGST1 contained mainly oligomannose Man5GlcNAc2 structure, but also hybrid- and larger oligommanose-type glycans in a lower proportion. Furthermore, purified OoGST1 showed prostaglandin synthase activity as confirmed by Liquid Chromatography (LC)/MS following a coupled-enzyme assay. This is only the second reported and characterized glycosylated GST and our study highlights its potential role in host-parasite interactions and use in the study of human onchocerciasis.


Assuntos
Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Onchocerca/enzimologia , Onchocerca/genética , Oncocercose/veterinária , Sequência de Aminoácidos , Animais , Bovinos/parasitologia , Doenças dos Bovinos/parasitologia , Cromatografia de Afinidade , Cromatografia Líquida , Feminino , Glicosilação , Espectrometria de Massas , Onchocerca volvulus/enzimologia , Onchocerca volvulus/genética , Oncocercose/parasitologia , Polissacarídeos/química , Prostaglandina-Endoperóxido Sintases/metabolismo , Estrutura Terciária de Proteína
18.
Parasit Vectors ; 12(1): 195, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31046820

RESUMO

BACKGROUND: In the Kingdom of Saudi Arabia (KSA), Leishmania major and L. tropica are the main causative agents of Old World cutaneous leishmaniasis (CL). The national CL treatment regimen consists of topical 1% clotrimazole/2% fusidic acid cream followed by 1-2 courses of intralesional sodium stibogluconate (SSG); however, treatment efficacy is highly variable and the reasons for this are not well understood. In this study, we present a complete epidemiological map of CL and determined the efficacy of the standard CL treatment regime in several endemic regions of KSA. RESULTS: Overall, three quarters of patients in all CL-endemic areas studied responded satisfactorily to the current treatment regime, with the remaining requiring only an extra course of SSG. The majority of unresponsive cases were infected with L. tropica. Furthermore, the development of secondary infections (SI) around or within the CL lesion significantly favoured the treatment response of L. major patients but had no effect on L. tropica cases. CONCLUSIONS: The response of CL patients to a national treatment protocol appears to depend on several factors, including Leishmania parasite species, geographical location and occurrences of SI. Our findings suggest there is a need to implement alternative CL treatment protocols based on these parameters.


Assuntos
Antiprotozoários/administração & dosagem , Coinfecção/parasitologia , Leishmania major/efeitos dos fármacos , Leishmania tropica/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Leishmania major/genética , Leishmania major/isolamento & purificação , Leishmania major/fisiologia , Leishmania tropica/genética , Leishmania tropica/isolamento & purificação , Leishmania tropica/fisiologia , Leishmaniose Cutânea/parasitologia , Masculino , Pessoa de Meia-Idade , Arábia Saudita , Resultado do Tratamento , Adulto Jovem
19.
Genome Res ; 28(9): 1383-1394, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30006414

RESUMO

African trypanosomes are vector-borne hemoparasites of humans and animals. In the mammal, parasites evade the immune response through antigenic variation. Periodic switching of the variant surface glycoprotein (VSG) coat covering their cell surface allows sequential expansion of serologically distinct parasite clones. Trypanosome genomes contain many hundreds of VSG genes, subject to rapid changes in nucleotide sequence, copy number, and chromosomal position. Thus, analyzing, or even quantifying, VSG diversity over space and time presents an enormous challenge to conventional techniques. Indeed, previous population genomic studies have overlooked this vital aspect of pathogen biology for lack of analytical tools. Here we present a method for analyzing population-scale VSG diversity in Trypanosoma congolense from deep sequencing data. Previously, we suggested that T. congolense VSGs segregate into defined "phylotypes" that do not recombine. In our data set comprising 41 T. congolense genome sequences from across Africa, these phylotypes are universal and exhaustive. Screening sequence contigs with diagnostic protein motifs accurately quantifies relative phylotype frequencies, providing a metric of VSG diversity, called the "variant antigen profile." We applied our metric to VSG expression in the tsetse fly, showing that certain, rare VSG phylotypes may be preferentially expressed in infective, metacyclic-stage parasites. Hence, variant antigen profiling accurately and rapidly determines the T. congolense VSG gene and transcript repertoire from sequence data, without need for manual curation or highly contiguous sequences. It offers a tractable approach to measuring VSG diversity across strains and during infections, which is imperative to understanding the host-parasite interaction at population and individual scales.


Assuntos
Polimorfismo Genético , Análise de Sequência de DNA/métodos , Trypanosoma congolense/genética , Glicoproteínas Variantes de Superfície de Trypanosoma/genética , Motivos de Aminoácidos , Animais , Masculino , Trypanosoma congolense/imunologia , Trypanosoma congolense/patogenicidade , Moscas Tsé-Tsé/parasitologia , Glicoproteínas Variantes de Superfície de Trypanosoma/química , Glicoproteínas Variantes de Superfície de Trypanosoma/imunologia
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