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1.
Small ; 19(31): e2300541, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37058095

RESUMO

Biodiesel remains one of the most promising alternatives to replace fossil fuel-derived petrodiesel. Nonetheless, conventional biodiesel synthesis relies on homogeneous alkali-based catalysts that involve long and tedious purification steps , increasing biodiesel production costs. Heterogeneous catalysts have emerged as promising alternatives to circumvent these drawbacks, as they can easily be recovered and reused. Herein, polymeric carbon nitride dots and nanosheets are synthesized through a solid-phase reaction between urea and sodium citrate. Their morphology and surface chemistry are tuned by varying the precursor's ratio, and the materials are investigated as catalysts in the transesterification reaction of canola oil to biodiesel. A conversion of > 98% is achieved using a 5 wt% catalyst loading, oil to methanol ratio of 1:36 at 90 °C for 4 h, with the performance maintained over at least five reuse cycles. In addition, the effect of the transesterification reaction parameters on the reaction kinetics is evaluated, which follows a pseudo-first-order (PFO) regime. Combined with a deep understanding of the catalyst's surface, these results have allowed us to propose a reaction mechanism similar to the one observed for homogenous alkali catalysts. These carbon nitride-based nanoparticles offer a metal-free and cost-effective alternative to conventional homogeneous and metal-based heterogeneous catalysts.

2.
Parasitology ; : 1-11, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36632020

RESUMO

Echinostoma paraensei, described in Brazil at the end of the 1960s and used as a biological model for a range of studies, belongs to the 'revolutum' complex of Echinostoma comprising species with 37 collar spines. However, molecular data are available only for a few isolates maintained under laboratory conditions, with molecular prospecting based on specimens originating from naturally infected hosts virtually lacking. The present study describes Echinostoma maldonadoi Valadão, Alves & Pinto n. sp., a species cryptically related to E. paraensei found in Brazil. Larval stages (cercariae, metacercariae and rediae) of the new species were found in the physid snail Stenophysa marmorata in the State of Minas Gerais, Brazil, the same geographical area where E. paraensei was originally described. Adult parasites obtained experimentally in Meriones unguiculatus were used for morphological (optical microscopy) and molecular [28S, internal transcribed spacer (ITS), nad1 and cox1] characterization. The morphology of larval and adult parasites (most notable the small-sized dorsal spines in the head collar), associated with low (0­0.1%) molecular divergence for 28S gene or ITS region, and only moderate divergence for the mitochondrial cox1 gene (3.83%), might suggest that the newly collected specimens should be assigned to E. paraensei. However, higher genetic divergence (6.16­6.39%) was found in the mitochondrial nad1, revealing that it is a genetically distinct, cryptic lineage. In the most informative phylogenetic reconstruction, based on nad1, E. maldonadoi n. sp. exhibited a strongly supported sister relationship with E. paraensei, which may indicate a very recent speciation event giving rise to these 2 species.

3.
J Am Acad Dermatol ; 87(3): 559-566, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35487332

RESUMO

BACKGROUND: The incidence of systemic lupus in children with discoid lupus is unknown. OBJECTIVE: This study assessed the baseline characteristics of patients with pediatric discoid lupus erythematosus (pDLE). METHODS: Medical records at 17 sites were reviewed for pediatric dermatology and rheumatology patients with discoid lupus erythematosus. The inclusion criteria were clinical and/or histopathologic diagnosis of discoid lupus erythematosus with an age at onset of <18 years. Baseline data were collected at the first documented visit. Outcomes included diagnosis of systemic lupus erythematosus (SLE) at the baseline visit using the 1997 American College of Rheumatology (primary) and the 2012 Systemic Lupus International Collaborating Clinics (secondary) criteria. RESULTS: Of the >1500 charts reviewed, 438 patients met the inclusion criteria. The cohort was predominantly female (72%) and racially/ethnically diverse. A diagnosis of SLE at the baseline visit (pDLE + SLE) was rendered in 162 (37%) patients using the American College of Rheumatology and in 181 (41%) patients using the Systemic Lupus International Collaborating Clinics criteria. Patients with pDLE + SLE were older at the time of rash onset (median, 12.9 vs 8.9 years; P < .001), with shorter time from discoid lupus erythematosus onset to diagnosis, compared with patients with pDLE-only (median, 2 vs 7 months; P < .001). Patients with pDLE + SLE were more likely to be female (P = .004), with generalized discoid lupus erythematosus and clinically aggressive disease, including end-organ involvement, positive serologies, and higher- titer levels of antinuclear antibodies (P < .001). LIMITATIONS: Retrospective study. CONCLUSION: A diagnosis of discoid lupus erythematosus in adolescence should prompt thorough screening for SLE.


Assuntos
Lúpus Eritematoso Discoide , Lúpus Eritematoso Sistêmico , Adolescente , Criança , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Lúpus Eritematoso Discoide/diagnóstico , Lúpus Eritematoso Discoide/epidemiologia , Lúpus Eritematoso Sistêmico/epidemiologia , Masculino , Estudos Retrospectivos
4.
Parasitology ; 149(3): 325-336, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35264265

RESUMO

Although Echinostoma robustum (currently a synonym of E. miyagawai) was reported in the Americas based on molecular data, morphological support on adult parasites is still required. Herein, a new species of Echinostoma is described based on worms found in a chicken from Brazil. Molecular phylogenetic analyses based on 28S (1063 bp), ITS (947 bp) and Nad-1 (442 bp) datasets reveal the inclusion of the new species within Echinostoma 'revolutum' species complex. Moreover, it was verified the conspecificity between cercariae previously identified as E. robustum in Brazil [identical ITS and only 0.3% of divergence (1 nucleotide) in Nad-1]. Species discovery analyses show that these two isolates form an independent lineage (species) among Echinostoma spp. Compared to E. miyagawai, the new species presents relatively high divergence in Nad-1 (7.88­9.09%). Morphologically, the specimens are distinguished from all nominal species from the 'revolutum' species complex by the more posterior position of the testes (length of post-testicular field as a proportion of body length about 20%). They further differ from E. miyagawai and South American Echinostoma spp. by the higher proportion of forebody to the body length. Therefore, combined molecular and morphological evidence supports the proposal of the species named here as Echinostoma pseudorobustum sp. nov.


Assuntos
Echinostoma , Echinostomatidae , Trematódeos , Animais , Brasil/epidemiologia , Echinostoma/anatomia & histologia , Echinostomatidae/genética , Filogenia
5.
Parasitol Res ; 121(3): 933-944, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35106652

RESUMO

Philophthalmus is a cosmopolitan genus of digeneans that includes ocular parasites of birds and mammals. Despite broad distribution and veterinary importance of these digeneans, there are still gaps in knowledge about their diversity and biology, especially in South America. Herein, we conducted morphological, life cycle, and molecular studies of megalurous cercariae found in aquatic gastropod molluscs Aylacostoma chloroticum and A. tuberculatum collected in the São Francisco River, Brazil. Adult parasites reared experimentally in the eyes of chicks are described here as Philophthalmus aylacostoma n. sp. The new species differs from its congeners known in the Americas by a combination of traits, including the sucker width ratio, the oral sucker to pharynx width ratio, egg size, and the type of vitellarium in adult forms. The new species is morphologically closest to Philophthalmus megalurus, from which it differs by the smaller body and larger eggs, as well as by the measurements of cercariae and the family of snails that act as the intermediate host. Molecular phylogenetic analysis based on 28S rDNA and comparison of cox1 sequences confirm that P. aylacostoma n. sp. is distinct from four previously sequenced named species of the genus. Moreover, cox1 sequences revealed conspecificity of our specimens with an isolate of Philophthalmus sp. previously reported, also in thiarid snails, in Paraná River, Brazil. The interspecific divergence in cox1 between the new species and other species with sequences available for comparison varied between 12 and 15%.


Assuntos
Gastrópodes , Trematódeos , Infecções por Trematódeos , Animais , Brasil , Galinhas/parasitologia , Gastrópodes/parasitologia , Estágios do Ciclo de Vida , Filogenia , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/veterinária
6.
Inorg Chem ; 60(16): 11795-11802, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34314164

RESUMO

Postsynthetic modification of metal-organic frameworks (MOFs) is an important strategy for accessing MOF analogues that cannot be easily synthesized de novo. In this work, the rare-earth (RE) cluster-based MOF Y-CU-10 with shp topology was modified through transmetalation using a series of RE ions, including La(III), Nd(III), Eu(III), Tb(III), Er(III), Tm(III), and Yb(III). In all cases, metal exchange higher than 70% was observed, with reproducible results. All transmetalated materials were fully characterized and compared to the parent MOF Y-CU-10 with regard to crystallinity, surface area, and morphology. Additionally, single-crystal X-ray diffraction measurements were performed to provide further evidence of transmetalation occurring in the nonanuclear cluster nodes of the MOF.

7.
Parasitology ; 148(7): 798-808, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33593464

RESUMO

Amphistome species belonging to the genus Catadiscus are poorly studied intestinal trematodes found primarily in Neotropical anurans. Herein, developmental stages of an amphistome species found during herpetological and malacological surveys in a temporary marsh pond from Brazil were subjected to morphological (light and scanning electron microscopy) and molecular analyses. Adult parasites recovered from anurans were identified as Catadiscus marinholutzi. Amphistome cercariae found in the planorbid snails Drepanotrema depressissimum and Drepanotrema lucidum from the same waterbody were used for experimental and molecular studies. Immature parasites, morphologically compatible with members of Catadiscus, were experimentally obtained in laboratory-reared tadpoles. Sequencing of a partial region of 28S rDNA gene of both adult and cercariae revealed 100% similarity between these developmental stages, confirming their conspecificity. Phylogenetic analyses were attempted for the first time to reveal the position of a species of Catadiscus in the superfamily Paramphistomoidea. Catadiscus marinholutzi falls in a virtual polytomy together with other paramphistomoids, which leaves its phylogenetic relationships within the group unclear. Moreover, the high genetic divergence to Diplodiscus spp. (10.06­10.84%) cast doubts on the placement of Catadiscus within Diplodiscidae. Hence the species composition of the Diplodiscidae should be re-evaluated in further studies using a broader spectrum of related taxa.


Assuntos
Anuros/parasitologia , Caramujos/parasitologia , Trematódeos/anatomia & histologia , Trematódeos/crescimento & desenvolvimento , Animais , Brasil , DNA de Helmintos/análise , DNA Ribossômico/análise , Filogenia , Trematódeos/classificação , Trematódeos/genética
8.
Parasitology ; 148(11): 1383-1391, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34103107

RESUMO

Typhlocoelum cucumerinum is a tracheal parasite of birds widely distributed across the globe. Nevertheless, aspects of the biology of this cyclocoelid are still poorly understood. Herein, we report the finding of T. cucumerinum in definitive and intermediate hosts from an urban waterbody of Brazil. The parasite was initially detected during the necropsy of domestic Muscovy ducks (Cairina moschata) found dead in the locality. Coproparasitological tests in live animals revealed that 12/47 (25.53%) Muscovy ducks and 2/8 (25%) mallards (Anas platyrhynchos platyrhynchos) were infected with T. cucumerinum. Moreover, rediae and metacercariae morphologically similar to T. cucumerinum were found in 3/248 (1.33%) Biomphalaria straminea collected in the same waterbody frequented by the birds. The conspecificity between the adult and the larval stages was confirmed molecularly (100% similarity in Cox-1). Moreover, the phylogenetic position of T. cucumerinum was determined for the first time based on partial fragments of the 28S, Cox-1 and Nad-1 genes. The species grouped with other members of the subfamily Typhlocoelinae with sequences available, but the data obtained do not support the distinctiveness of the genera Typhlocoelum and Tracheophilus. Further studies involving a broader range of species can result in taxonomic rearrangements in Typhlocoelinae.


Assuntos
Doenças das Aves/parasitologia , Patos/parasitologia , Traqueia/parasitologia , Doenças da Traqueia/veterinária , Trematódeos/isolamento & purificação , Infecções por Trematódeos/veterinária , Animais , Doenças das Aves/diagnóstico , Aves , Brasil/epidemiologia , Meio Ambiente , Fezes/parasitologia , Interações Hospedeiro-Parasita , Larva , Estágios do Ciclo de Vida , Moluscos/parasitologia , Filogenia , Alinhamento de Sequência , Doenças da Traqueia/diagnóstico , Doenças da Traqueia/parasitologia , Trematódeos/classificação , Trematódeos/genética , Trematódeos/crescimento & desenvolvimento , Infecções por Trematódeos/diagnóstico , Infecções por Trematódeos/parasitologia
9.
J Physiol ; 598(11): 2243-2256, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32083718

RESUMO

KEY POINTS: Respiratory muscle strength is compromised in people with tetraplegia, which may be compensated for by an increase in neural drive to the diaphragm. We found that the discharge frequencies of diaphragm motor units are higher in people with chronic tetraplegia compared with able-bodied people during quiet breathing. Furthermore, we found that the area of single motor unit potentials was increased in people with tetraplegia. These results suggest an increased motoneurone output to the diaphragm and remodelling of diaphragm motor units to maintain ventilation in tetraplegia. ABSTRACT: People with tetraplegia have reduced inspiratory muscle strength, ∼40% of able-bodied individuals. Paralysed or partially paralysed respiratory muscles as a result of tetraplegia compromise lung function, increase the incidence of respiratory infections and can cause dyspnoea. We hypothesised that reduced inspiratory muscle strength in tetraplegia may increase neural drive to the inspiratory muscles to maintain ventilation. We recorded the discharge properties of single motor units from the diaphragm in participants with chronic tetraplegia (8 males, 42-78 years, C3-C6 injury, AIS A-C) and able-bodied control participants (6 males matched for age and body mass index). In each group, 117 and 166 single motor units, respectively, were discriminated from recordings in the costal diaphragm using a monopolar electrode. A linear mixed-effects model analysis showed higher peak discharge frequencies of motor units during quiet breathing in tetraplegia (17.8 ± 4.9 Hz; mean ± SD) compared with controls (12.4 ± 2.2 Hz) (P < 0.001). There were no differences in tidal volume, inspiratory time or mean air flow between groups. Motor unit potentials in tetraplegia, compared with controls, were larger in amplitude (1.1 ± 0.7 mV and 0.5 ± 0.3 mV, respectively, P = 0.007) and area (1.83 ± 1.49 µV ms and 0.69 ± 0.52 µV ms, respectively, P = 0.003). The findings indicate that diaphragm motor unit remodelling is likely to have occurred in people with chronic tetraplegia and that there is an increase in diaphragm motor unit discharge rates during quiet breathing. These neural changes ensure that ventilation is maintained in people with chronic tetraplegia.


Assuntos
Diafragma , Alta do Paciente , Eletromiografia , Humanos , Masculino , Quadriplegia , Respiração , Músculos Respiratórios
10.
Analyst ; 145(16): 5419-5424, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32589168

RESUMO

In this communication, molecularly imprinted nanoparticles (nanoMIPs) that are produced by solid-phase synthesis are functionalised onto thermistors via dip-coating. These thermistors are soldered onto a printed-circuit board to facilitate electrical detection. Subsequently, these are inserted into a home-made thermal device that can measure the selective binding of biomolecules to the nanoMIP layer via monitoring the thermal resistance (Rth) at the solid-liquid interface. This thermal analysis technique, referred to as the Heat-Transfer Method, has previously been used for detection of proteins with MIP-based binders. While offering the advantages of low-cost and label free analysis, this method is limited by the high noise on the feedback loop and not being commercially available. These disadvantages can be overcome by the use of thermistors, which offer superior temperature sensitivity compared to thermocouples, and its electrical read-out can be easily integrated into portable devices. To our knowledge, this is the first report where MIPs are directly integrated onto thermistors for detection purposes. Measurements were conducted with an epitope of epidermal growth factor receptor (EGFR) and trypsin, where the electrical resistance was correlated to the biomolecule concentration. For both EGFR and trypsin, an enhanced signal to noise ratio for the electrical measurements was observed compared to previous analysis that was based on thermal resistance. The sensitivity of the sensors in buffered solution was in the nanomolar range, which is compatible with physiologically relevant concentrations. Upon exposure of the nanoMIP for EGFR towards pepsin no significant change in the resistance was yielded, establishing the selectivity of the developed sensor platform. Besides the enhanced sensitivity, the use of thermistors will enable miniaturisation of the device and has potential for in vivo measurements since specified electrochemical measurements are compatible with human use. To highlight the versatility of the nanoMIPs, this work should be extended to a set of biomolecules with various structures, with the possibility of extending this to an array format.


Assuntos
Impressão Molecular , Nanopartículas , Humanos , Peptídeos , Polímeros , Técnicas de Síntese em Fase Sólida
11.
Parasitol Res ; 119(8): 2511-2520, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32562066

RESUMO

Zygocotyle lunata inhabits the caecum of birds and mammals from the American continent. This amphistome parasite is easily maintained in the laboratory and serves as a model organism in life-cycle studies, but it has seldom been studied using molecular data. Neither the position of Z. lunata in the superfamily Paramphistomoidea nor the monophyly of the Zygocotylidae has been evaluated with molecular phylogenetic methods. In the present study, adult specimens of Z. lunata obtained experimentally in mice from Brazil were submitted to molecular studies. Partial sequences of nuclear (1261 bp of 28S and 418 bp of 5.8S-ITS-2) and mitochondrial (1410 bp of cytochrome c oxidase 1, cox1) markers were compared with published data. In the most well-resolved phylogeny, based on 28S sequences, Z. lunata clustered in a well-supported clade with Wardius zibethicus, the only other species currently included in the Zygocotylidae, thus confirming the validity of this family. Divergence of 28S sequences between these species was 2.2%, which falls in the range of intergeneric variation (0.9-5.6%) observed in the other two monophyletic groups in the 28S tree, i.e., representatives of Gastrodicidae and Neotropical cladorchiids (Cladorchiidae). Analysis of ITS-2 and two parts of the cox1 gene placed Z. lunata within poorly resolved clades or large polytomies composed of several paramphistomoid families, without clarifying higher-level phylogenetic relationships. The cox1 of a Brazilian isolate of Z. lunata is 99.6% similar to a Canadian isolate, confirming the pan-American distribution of the species. Finally, our phylogenetic reconstructions of Paramphistomoidea revealed a complex scenario in the taxonomic composition of some amphistome families, which highlights a need for further integrative studies that will likely result in rearrangements of traditional morphology-based classifications.


Assuntos
Doenças das Aves/parasitologia , Ceco/parasitologia , Paramphistomatidae/genética , Paramphistomatidae/isolamento & purificação , Filogenia , Infecções por Trematódeos/veterinária , Animais , Aves/parasitologia , Brasil , Canadá , Feminino , Estágios do Ciclo de Vida , Masculino , Camundongos , Paramphistomatidae/classificação , Paramphistomatidae/crescimento & desenvolvimento , Infecções por Trematódeos/parasitologia
12.
J Physiol ; 597(20): 5079-5092, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31429072

RESUMO

KEY POINTS: Ageing is associated with changes in the respiratory system including in the lungs, rib cage and muscles. Neural drive to the diaphragm, the principal inspiratory muscle, has been reported to increase during quiet breathing with ageing. We demonstrated that low-threshold motor units of the human diaphragm recruited during quiet breathing have similar discharge frequencies across age groups and shorter discharge times in older age. With ageing, motor unit action potential area increased. We propose that there are minimal functionally significant changes in the discharge properties of diaphragm motor units with ageing despite remodelling of the motor unit in the periphery. ABSTRACT: There are changes in the skeletal, pulmonary and respiratory neuromuscular systems with healthy ageing. During eupnoea, one study has shown relatively higher crural diaphragm electromyographic activity (EMG) in healthy older adults (>51 years) than in younger adults, but these measures may be affected by the normalisation process used. A more direct method to assess neural drive involves the measurement of discharge properties of motor units. Here, to assess age-related changes in neural drive to the diaphragm during eupnoea, EMG was recorded from the costal diaphragm using a monopolar needle electrode in participants from three age groups (n ≥ 7 each): older (65-80 years); middle-aged (43-55 years) and young (23-26 years). In each group, 154, 174 and 110 single motor units were discriminated, respectively. A mixed-effects linear model showed no significant differences between age groups for onset (group mean range 9.5-10.2 Hz), peak (14.1-15.0 Hz) or offset (7.8-8.5 Hz) discharge frequencies during eupnoea. The motor unit recruitment was delayed in the older group (by ∼15% of inspiratory time; p = 0.02 cf. middle-aged group) and had an earlier offset time (by ∼15% of inspiratory time; p = 0.04 cf. young group). However, the onset of multiunit activity was similar across groups, consistent with no global increase in neural drive to the diaphragm with ageing. The area of diaphragm motor unit potentials was ∼40% larger in the middle-aged and older groups (P < 0.02), which indicates axonal sprouting and re-innervation of muscle fibres associated with ageing, even in middle-aged participants.


Assuntos
Envelhecimento/fisiologia , Diafragma/inervação , Diafragma/fisiologia , Canais de Potássio Ativados por Sódio/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Artérias/citologia , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miócitos de Músculo Liso/fisiologia , Canais de Potássio Ativados por Sódio/genética , Testes de Função Respiratória , Adulto Jovem
13.
Br J Dermatol ; 180(6): 1430-1437, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30637718

RESUMO

BACKGROUND: Cutaneous lupus erythematosus (CLE) is a potentially disfiguring, chronic autoimmune disease with variable skin manifestations, negatively affecting patients' quality of life (QoL). Patient-reported outcome (PRO) measures assessing QoL in patients with CLE have been generic or developed without input from patients. OBJECTIVES: To demonstrate the reliability and validity of a disease-specific QoL measure for CLE - the cutaneous lupus erythematosus quality of life (CLEQoL). METHODS: One hundred and one patients with CLE were recruited, and each patient was asked to complete the CLEQoL. Internal consistency was used as a measure of reliability. Validity was measured in two ways - structural validity via exploratory factor analysis and convergent validity via Spearman correlations between CLEQoL and the Short Form 36 (SF-36), visual analogue scales and clinical variables. Patient demographic and disease characteristics were collected. RESULTS: The mean ± SD age of patients with CLE was 48 ± 13 years, with discoid lupus (n = 72; 71.3%) being the most predominant CLE subtype. Patients were mostly female (n = 88; 87·1%) and African American/Black (n = 59; 58·4%). Internal consistency ranged from 0·67 to 0·97. Five domains (functioning, emotions, symptoms, body image/cosmetic effects and photosensitivity) were extracted with a total explained variance of 71·1%. CLEQoL-related domains correlated with SF-36 domains (r range -0·39 to -0·65). CONCLUSIONS: The CLEQoL was found to be a valid and reliable PRO measure for assessing QoL in patients with CLE. Demonstrating that the CLEQoL has strong psychometric properties is an important step towards the development of a disease-specific PRO measure that future clinical trials can use.


Assuntos
Lúpus Eritematoso Cutâneo/complicações , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Inquéritos e Questionários , Adulto , Feminino , Humanos , Lúpus Eritematoso Cutâneo/psicologia , Masculino , Pessoa de Meia-Idade , Psicometria/métodos , Reprodutibilidade dos Testes
14.
Exp Parasitol ; 199: 74-79, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30840851

RESUMO

Paramphistomes are important parasites in veterinary medicine. There are few anthelmintic drugs available against them. The development of new drugs is urgently needed and this process can be accelerated through the development of rodent models for in vivo testing. Among the few paramphistomes that develop in rodents is the caecal fluke Zygocotyle lunata, a species with which several biological studies have been performed over several decades. Nevertheless, its use as a model for evaluation of anthelmintic drugs had not yet been evaluated. In the present study, we evaluated the efficacy of praziquantel (PZQ 300 mg/kg 5x), albendazole (ABZ 200 mg/kg 5x) and closantel (CLO 50 mg/kg single dose, 50 mg/kg 3x and 25 mg/kg 3x) for treatment of mice experimentally infected with Z. lunata. The animals were infected with 20 metacercariae of the parasite and were treated 30 days post-infection. Untreated groups were maintained as controls. Seven days after the treatments, the animals were euthanized for recovery and counting of parasites. We found that PZQ and ABZ, at the dosages and therapeutic schedule employed here, did not cause significant alterations in worm burden [worm counts 16.0 ±â€¯2.8 (13-19), 17.6 ±â€¯2.1 (14-19) and 16.2 ±â€¯1.9 (13-18) (p = 0.51) in PZQ, ALB and control, respectively]. CLO 50 mg/kg in a single dose caused significant reduction in the number of parasites [treated: 1.8 ±â€¯0.9 (1-3); control: 15.6 ±â€¯2.5 (12-19)], although it did not result in complete elimination of the parasites in any animal. Despite the fact that three doses of CLO 50 mg/kg or CLO 25 mg/kg caused complete elimination of the parasites in most surviving animals, there was significant host mortality. In general, results here obtained are concordant with those of studies performed on ruminant paramphistomes. Given that Z. lunata can be maintained in laboratory rodents, it is a suitable model for screening anthelmintic drugs against paramphistomes.


Assuntos
Albendazol/uso terapêutico , Anti-Helmínticos/uso terapêutico , Paramphistomatidae/efeitos dos fármacos , Praziquantel/uso terapêutico , Salicilanilidas/uso terapêutico , Infecções por Trematódeos/tratamento farmacológico , Albendazol/química , Albendazol/farmacologia , Análise de Variância , Animais , Anti-Helmínticos/química , Anti-Helmínticos/farmacologia , Fezes/parasitologia , Masculino , Camundongos , Paramphistomatidae/classificação , Paramphistomatidae/isolamento & purificação , Praziquantel/química , Praziquantel/farmacologia , Salicilanilidas/química , Salicilanilidas/farmacologia , Infecções por Trematódeos/parasitologia
15.
Emerg Infect Dis ; 24(3): 606-608, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29460753

RESUMO

We investigated the transmission of the fishborne trematodes Centrocestus formosanus and Haplorchis pumilio by Melanoides tuberculata snails in Peru. We report on results of experimental, morphological, and molecular approaches and discuss the potential risk for future human cases, given the existence of food habits in the country involving the ingestion of raw fish.


Assuntos
Peixes/parasitologia , Gastrópodes/parasitologia , Caramujos/parasitologia , Zoonoses/parasitologia , Zoonoses/transmissão , Animais , Peru/epidemiologia , Platelmintos , Zoonoses/epidemiologia
16.
AIDS Care ; 30(7): 836-843, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29409344

RESUMO

The People Living with HIV StigmaSurvey UK 2015 was a community led national survey investigating experiences of people living with HIV in the UK in the past 12 months. Participants aged 18 and over were recruited through over 120 cross-sector community organisations and 46 HIV clinics to complete an anonymous online survey. Trans is an umbrella term which refers to individuals whose current gender identity is different to the gender they were assigned at birth. Trans participants self-identified via gender identity and gender at birth questions. Descriptive analyses of reported experiences in social and health care settings were conducted and multivariate logistic regression analyses were used to identify sociodemographic predictors of reporting being treated differently to non-HIV patients, and being delayed or refused healthcare treatment in the past 12 months. 31 out of 1576 participants (2%) identified as trans (19 trans women, 5 trans men, 2 gender queer/non-binary, 5 other). High levels of social stigma were reported for all participants, with trans participants significantly more likely to report worrying about verbal harassment (39% vs. 23%), and exclusion from family gatherings (23% vs. 9%) in the last 12 months, compared to cisgender participants. Furthermore, 10% of trans participants reported physical assault in the last 12 months, compared to 4% of cisgender participants. Identifying as trans was a predictor of reporting being treated differently to non-HIV patients (48% vs. 30%; aOR 2.61, CI 1.06, 6.42) and being delayed or refused healthcare (41% vs. 16%; aOR 4.58, CI 1.83, 11.44). Trans people living with HIV in the UK experience high levels of stigma and discrimination, including within healthcare settings, which is likely to impact upon health outcomes. Trans-specific education and awareness within healthcare settings could help to improve service provision for this demographic.


Assuntos
Infecções por HIV/psicologia , Discriminação Social , Estigma Social , Pessoas Transgênero/psicologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Reino Unido , Adulto Jovem
17.
AIDS Care ; 30(9): 1189-1196, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29806466

RESUMO

We aim to understand the difference in stigma and discrimination, in particular sexual rejection, experienced between gay and heterosexual men living with HIV in the UK. The People Living with HIV StigmaSurvey UK 2015 recruited a convenience sample of persons with HIV through over 120 cross sector community organisations and 46 HIV clinics to complete an online survey. 1162 men completed the survey, 969 (83%) gay men and 193 (17%) heterosexual men, 92% were on antiretroviral therapy. Compared to heterosexual men, gay men were significantly more likely to report worrying about workplace treatment in relation to their HIV (21% vs. 11%), worrying about HIV-related sexual rejection (42% vs 21%), avoiding sex because of their HIV status (37% vs. 23%), and experiencing HIV-related sexual rejection (27% vs. 9%) in the past 12 months. In a multivariate logistic regression controlling for other sociodemographic factors, being gay was a predictor of reporting HIV-related sexual rejection in the past 12 months (aOR 2.17, CI 1.16, 4.02). Both gay and heterosexual men living with HIV experienced stigma and discrimination in the past 12 months, and this was higher for gay men in terms of HIV-related sexual rejection. Due to the high proportion of men reporting sexual rejection, greater awareness and education of the low risk of transmission of HIV among people on effective treatment is needed to reduce stigma and sexual prejudice towards people living with HIV.


Assuntos
Infecções por HIV/psicologia , Heterossexualidade , Homofobia , Homossexualidade Masculina , Estigma Social , Adolescente , Adulto , Conscientização , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Comportamento Sexual , Inquéritos e Questionários , Reino Unido , Adulto Jovem
18.
Br J Anaesth ; 121(1): 86-94, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29935600

RESUMO

BACKGROUND: Transitions into and out of the anaesthetised state exhibit resistance to state transitions known as neural inertia. As a consequence, emergence from anaesthesia occurs at a consistently lower anaesthetic concentration than induction. Motivated by stochastic switching between discrete activity patterns observed at constant anaesthetic concentration, we investigated the consequences of such switching for neural inertia. METHODS: We simulated stochastic switching in MATLAB as Brownian motion on an energy landscape or equivalently as a discrete Markov process. Effects of anaesthetics were modelled as changing stability of the awake and the anaesthetised states. Simulation results were compared with re-analysed neural inertia data from mice and Drosophila. RESULTS: Diffusion on a two-well energy landscape gives rise to hysteresis. With additive noise, hysteresis collapses. This collapse occurs over a mixing time that is independent from pharmacokinetics. The two-well potential gives rise to the leftward shift for the emergence dose-response curve. Yet, from in vivo data, ΔEC50 and Δ Hill slope are strongly negatively correlated (R2=0.45, P<1.7×10-15). This correlation is not explained by a two-well potential. The extension of the diffusion model to a Markov process with 10 states (three awake, seven unconscious) reproduces both the left shift and the shallower Hill slope for emergence. CONCLUSIONS: Stochastic state switching accounts for all known features of neural inertia. More than two states are required to explain the consistent increase observed in variability of recovery from general anaesthesia. This model predicts that hysteresis should collapse with a time scale independent of anaesthetic drug pharmacokinetics.


Assuntos
Período de Recuperação da Anestesia , Anestesia Geral , Fenômenos Fisiológicos do Sistema Nervoso/efeitos dos fármacos , Processos Estocásticos , Algoritmos , Anestésicos/farmacocinética , Anestésicos/farmacologia , Simulação por Computador , Eletroencefalografia , Humanos , Cadeias de Markov , Modelos Teóricos
19.
Nature ; 482(7385): 357-62, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22337055

RESUMO

Species diversity can be lost through two different but potentially interacting extinction processes: demographic decline and speciation reversal through introgressive hybridization. To investigate the relative contribution of these processes, we analysed historical and contemporary data of replicate whitefish radiations from 17 pre-alpine European lakes and reconstructed changes in genetic species differentiation through time using historical samples. Here we provide evidence that species diversity evolved in response to ecological opportunity, and that eutrophication, by diminishing this opportunity, has driven extinctions through speciation reversal and demographic decline. Across the radiations, the magnitude of eutrophication explains the pattern of species loss and levels of genetic and functional distinctiveness among remaining species. We argue that extinction by speciation reversal may be more widespread than currently appreciated. Preventing such extinctions will require that conservation efforts not only target existing species but identify and protect the ecological and evolutionary processes that generate and maintain species.


Assuntos
Evolução Biológica , Eutrofização/fisiologia , Extinção Biológica , Especiação Genética , Salmonidae/fisiologia , Animais , Biodiversidade , Europa (Continente) , Lagos , Modelos Biológicos , Fenótipo , Salmonidae/genética
20.
Am J Emerg Med ; 36(8): 1451-1454, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29747896

RESUMO

OBJECTIVES: In response to crowding the use of hallway beds has become an increasingly prevalent practice in Emergency Departments (EDs). There is limited research on whether caring for patients in hallways (HP) is associated with adverse outcomes. The goal of this study was to examine the effects of HP triage on 30 day outcomes for ED return, readmission, and mortality. METHODS: We performed a retrospective cohort study at an urban, academic ED comparing HPs (defined as HP for ≥30 min) to matched controls triaged to standard ED beds from 9/30/14 to 10/1/15. We analyzed data from the hospital's clinical data warehouse. Matched controls were selected by gender, age, ethnicity, and language. We used McNemar's test to assess the association between triage location and 30 day study outcomes. We also examined adverse outcomes by triage severity using McNemar's test. RESULTS: A total of 10,608 HPs were matched to control patients. Compared to controls, HPs had 2.0 times the odds of returning to the ED in 30 days (95% CI: 1.8-2.1), 1.6 times the odds of inpatient readmission (95% CI: 1.4-1.9), and 1.7 times the odds of readmission to observation (95% CI: 1.4-2.0). The odds ratio for mortality in HPs versus controls was 0.80, (95% CI: 0.50-1.3). CONCLUSIONS: Patients initially triaged to the hallway have an increased odds of 30 day return to the ED, observation and inpatient admission. After adjusting for ESI, the increased odds for return remained similar. The small sample size precluded testing effects of HP status on mortality.


Assuntos
Aglomeração , Serviço Hospitalar de Emergência/organização & administração , Readmissão do Paciente/estatística & dados numéricos , Quartos de Pacientes , Triagem , Adulto , Boston , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Fatores de Tempo
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