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1.
Parasit Vectors ; 17(1): 186, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38605395

RESUMEN

Starting in October 2021, quarterly malacological surveys have been undertaken in Malawi, with the sampling of 12 specified freshwater habitats throughout a calendar year. Each survey monitors the presence of aquatic intermediate snail hosts of medical and veterinary importance. In March 2023, the alien lymnaeid species Pseudosuccinea columella was encountered for the first time in the surveys, in Nsanje District. This species identity was later confirmed upon DNA analysis of mitochondrial ribosomal 16S sequences. In July 2023, P. columella was also noted at single sites within Mangochi and Chikwawa Districts, and again in Nsanje District, with an additional location observed. Of particular importance, our sampled location in Mangochi District was directly connected to Lake Malawi, which expands the species list of invasive molluscs in this lake. While P. columella is a well-known intermediate snail host for human and animal fascioliasis, screening collected snails for trematode cercariae, alongside molecular xenomonitoring, did not yield equivocal evidence of active fluke infection. However, the newly recognized presence of this alien intermediate snail host within Lake Malawi, and along the Shire River Valley, flags a new concern in altered local transmission potential for human and animal fascioliasis.


Asunto(s)
Fasciola hepatica , Fascioliasis , Animales , Humanos , Fasciola hepatica/genética , Fascioliasis/veterinaria , Malaui , Caracoles
2.
Int J Parasitol Parasites Wildl ; 23: 100919, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38495311

RESUMEN

The freshwater amphibious snail Orientogalba viridis commonly occurs in eastern Asia, on certain Pacific islands and more importantly has recently dispersed into Europe. Since this snail is now considered an invasive species, its distribution is of growing parasitological interest as an alien intermediate host for various trematodes, particularly liver flukes. As part of ongoing surveillance for snail-borne diseases in Malawi, a population of O. viridis was first observed in May 2023, alongside an alarming presence of a human schistosome cercaria. This snail population later underwent detailed morphological characterisation with both snail and parasite identities confirmed upon DNA barcoding. This seminal observation triggered more extensive local snail surveys, finding 3 further populations in separated rice paddies, with further field-caught snails (n = 465) screened for infection and a selection used for repeated experimental challenges with miracidia from Schistosoma haematobium and Schistosoma mattheei. Although no field-caught (and experimentally exposed) snail was seen to shed schistosome cercariae, molecular xenomonitoring for schistosomiasis provided tangible evidence of putative transmission potential. Our first report of O. viridis here in Malawi, and more broadly in Africa, flags a need for increased vigilance for this invasive species alongside local clarification(s) of its transmission potential for trematodiases of either medical and/or veterinary importance.

3.
J Helminthol ; 96: e79, 2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36305615

RESUMEN

As part of surveillance of snail-borne trematodiasis in Knowsley Safari (KS), Prescot, United Kingdom, a collection was made in July 2021 of various planorbid (n = 173) and lymnaeid (n = 218) snails. These were taken from 15 purposely selected freshwater habitats. In the laboratory emergent trematode cercariae, often from single snails, were identified by morphology with a sub-set, of those most accessible, later characterized by cytochrome oxidase subunit 1 (cox1) DNA barcoding. Two schistosomatid cercariae were of special note in the context of human cercarial dermatitis (HCD), Bilharziella polonica emergent from Planorbarius corneus and Trichobilharzia spp. emergent from Ampullacaena balthica. The former schistosomatid was last reported in the United Kingdom over 50 years ago. From cox1 analyses, the latter likely consisted of two taxa, Trichobilharzia anseri, a first report in the United Kingdom, and a hitherto unnamed genetic lineage having some affiliation with Trichobilharzia longicauda. The chronobiology of emergent cercariae from P. corneus was assessed, with the vertical swimming rate of B. polonica measured. We provide a brief risk appraisal of HCD for public activities typically undertaken within KS educational and recreational programmes.


Asunto(s)
Dermatitis , Schistosomatidae , Esquistosomiasis , Enfermedades Cutáneas Parasitarias , Infecciones por Trematodos , Humanos , Animales , Schistosomatidae/genética , Enfermedades Cutáneas Parasitarias/epidemiología , Infecciones por Trematodos/epidemiología , Cercarias/genética , Dermatitis/epidemiología
4.
J Microbiol Methods ; 189: 106299, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34370997

RESUMEN

BACKGROUND: Phytophthora pluvialis was first described in 2013 and is the causal agent of red needle cast (RNC) in Pinus radiata as well as infection in Douglas fir (Pseudotsuga menziesii). A species-specific PCR is necessary for detection of this pathogen and diagnosis of RNC. OBJECTIVE: To design and validate a species-specific molecular assay for P. pluvialis using isolates from infected pine needles. METHODS: Species-specific PCR primers were generated from the ras-related GTP-binding protein 1 gene (ypt1) gene sequence, concentrating on DNA regions unique to P. pluvialis, and real-time and quantitative polymerase chain reaction (qPCR) were used to detect P. pluvialis from both artificially inoculated and naturally infected samples. RESULTS: The species-specific PCR assay was generated following P. pluvialis DNA sequence analysis. In vitro tests of the specificity of the probe-based, quantitative, polymerase chain reaction (qPCR) assay showed that no amplification was observed with other Phytophthora species including other closely-related clade 3 species, or with fungal species associated with pine or with pine DNA. The limit of detection of the qPCR assay was 2 pg/µl. When the qPCR assay was used to detect P. pluvialis in artificially-inoculated and naturally infected P. radiata needles, a PCR product was detected in all inoculated samples; the mean concentration ranges of P. pluvialis DNA in the inoculated and naturally infected samples tested were 5.9-124.5 pg/µl and 8.1-340.2 pg/µl, respectively. The assays described herein were used with serological diagnostic strips, providing the ability to identify to species level. CONCLUSIONS: The assay described herein detects P. pluvialis with high specificity and sensitivity from a range of DNA samples, including those extracted from infected plant material and serological diagnostic strips. The ability to detect and identify P. pluvialis, from infected tissues directly, provides value and practicality to diagnostics, biosecurity and research.


Asunto(s)
Técnicas de Amplificación de Ácido Nucleico , Phytophthora/genética , Pinus/microbiología , Enfermedades de las Plantas/microbiología , Cartilla de ADN/genética , Phytophthora/clasificación , Phytophthora/patogenicidad , Sensibilidad y Especificidad , Análisis de Secuencia de ADN
8.
Hear Res ; 375: 66-74, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30827780

RESUMEN

Cisplatin-induced ototoxicity results in significant, permanent hearing loss in pediatric and adult cancer survivors. Elucidating the mechanisms underlying cisplatin-induced hearing loss as well as the development of therapies to reduce and/or reverse cisplatin ototoxicity have been impeded by suboptimal animal models. Clinically, cisplatin is most commonly administered in multi-dose, multi-cycle protocols. However, many animal studies are conducted using single injections of high-dose cisplatin, which is not reflective of clinical cisplatin administration protocols. Significant limitations of both high-dose, single-injection protocols and previous multi-dose protocols in rodent models include high mortality rates and relatively small changes in hearing sensitivity. These limitations restrict assessment of both long-term changes in hearing sensitivity and effects of potential protective therapies. Here, we present a detailed method for an optimized mouse model of cisplatin ototoxicity that utilizes a multi-cycle administration protocol that better approximates the type and degree of hearing loss observed clinically. This protocol results in significant hearing loss with very low mortality. This mouse model of cisplatin ototoxicity provides a platform for examining mechanisms of cisplatin-induced hearing loss as well as developing therapies to protect the hearing of cancer patients receiving cisplatin therapy.


Asunto(s)
Cisplatino/toxicidad , Ototoxicidad/etiología , Animales , Umbral Auditivo/efectos de los fármacos , Cisplatino/administración & dosificación , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Esquema de Medicación , Potenciales Evocados Auditivos del Tronco Encefálico/efectos de los fármacos , Femenino , Células Ciliadas Auditivas Externas/efectos de los fármacos , Células Ciliadas Auditivas Externas/patología , Humanos , Masculino , Ratones , Ratones Endogámicos CBA , Emisiones Otoacústicas Espontáneas/efectos de los fármacos , Ototoxicidad/patología , Ototoxicidad/fisiopatología
9.
Parasitology ; 145(13): 1700-1714, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30246664

RESUMEN

In Cameroon, there is a national programme engaged in the control of schistosomiasis and soil-transmitted helminthiasis. In certain locations, the programme is transitioning from morbidity control towards local interruption of parasite transmission. The volcanic crater lake villages of Barombi Mbo and Barombi Kotto are well-known transmission foci and are excellent context-specific locations to assess appropriate disease control interventions. Most recently they have served as exemplars of expanded access to deworming medications and increased environmental surveillance. In this paper, we review infection dynamics through time, beginning with data from 1953, and comment on the short- and long-term success of disease control. We show how intensification of local control is needed to push towards elimination and that further environmental surveillance, with targeted snail control, is needed to consolidate gains in preventive chemotherapy as well as empower local communities to take ownership of interventions.


Asunto(s)
Monitoreo del Ambiente , Lagos/parasitología , Esquistosomiasis Urinaria/prevención & control , Caracoles/parasitología , Suelo/parasitología , Adolescente , Animales , Bulinus/parasitología , Camerún/epidemiología , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Prevalencia , Schistosoma haematobium/efectos de los fármacos , Esquistosomiasis Urinaria/epidemiología
10.
Phys Rev Lett ; 118(15): 151102, 2017 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-28452534

RESUMEN

Interferometric gravitational wave detectors operate with high optical power in their arms in order to achieve high shot-noise limited strain sensitivity. A significant limitation to increasing the optical power is the phenomenon of three-mode parametric instabilities, in which the laser field in the arm cavities is scattered into higher-order optical modes by acoustic modes of the cavity mirrors. The optical modes can further drive the acoustic modes via radiation pressure, potentially producing an exponential buildup. One proposed technique to stabilize parametric instability is active damping of acoustic modes. We report here the first demonstration of damping a parametrically unstable mode using active feedback forces on the cavity mirror. A 15 538 Hz mode that grew exponentially with a time constant of 182 sec was damped using electrostatic actuation, with a resulting decay time constant of 23 sec. An average control force of 0.03 nN was required to maintain the acoustic mode at its minimum amplitude.

11.
Anaesthesia ; 72(3): 350-358, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27804116

RESUMEN

Although the incidence of major adverse events in surgical daycare centres is low, these critical events may not be managed optimally due to the absence of resources that exist in larger hospitals. We aimed to study the impact of operating theatre critical event checklists on medical management and teamwork during whole-team operating theatre crisis simulations staged in a surgical daycare facility. We studied 56 simulation encounters (without and with a checklist available) divided between an initial session and then a retention session several months later. Medical management and teamwork were quantified via percentage adherence to key processes and the Team Emergency Assessment Measure, respectively. In the initial session, medical management was not improved by the presence of a checklist (56% without checklist vs. 62% with checklist; p = 0.50). In the retention session, teams performed significantly worse without the checklists (36% without checklist vs. 60% with checklist; p = 0.04). We did not observe a change in non-technical skills in the presence of a checklist in either the initial or retention sessions (68% without checklist vs. 69% with checklist (p = 0.94) and 69% without checklist vs. 65% with checklist (p = 0.36), respectively). Critical events checklists do not improve medical management or teamwork during simulated operating theatre crises in an ambulatory surgical daycare setting.


Asunto(s)
Procedimientos Quirúrgicos Ambulatorios/normas , Lista de Verificación , Complicaciones Intraoperatorias/terapia , Quirófanos/organización & administración , Grupo de Atención al Paciente/organización & administración , Competencia Clínica , Urgencias Médicas , Adhesión a Directriz/estadística & datos numéricos , Humanos , Ontario , Guías de Práctica Clínica como Asunto , Distribución Aleatoria , Análisis y Desempeño de Tareas
12.
Rev Sci Instrum ; 88(12): 124501, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29289175

RESUMEN

This paper presents an analysis of the transient behavior of the Advanced LIGO (Laser Interferometer Gravitational-wave Observatory) suspensions used to seismically isolate the optics. We have characterized the transients in the longitudinal motion of the quadruple suspensions during Advanced LIGO's first observing run. Propagation of transients between stages is consistent with modeled transfer functions, such that transient motion originating at the top of the suspension chain is significantly reduced in amplitude at the test mass. We find that there are transients seen by the longitudinal motion monitors of quadruple suspensions, but they are not significantly correlated with transient motion above the noise floor in the gravitational wave strain data, and therefore do not present a dominant source of background noise in the searches for transient gravitational wave signals. Using the suspension transfer functions, we compared the transients in a week of gravitational wave strain data with transients from a quadruple suspension. Of the strain transients between 10 and 60 Hz, 84% are loud enough that they would have appeared above the sensor noise in the top stage quadruple suspension monitors if they had originated at that stage at the same frequencies. We find no significant temporal correlation with the suspension transients in that stage, so we can rule out suspension motion originating at the top stage as the cause of those transients. However, only 3.2% of the gravitational wave strain transients are loud enough that they would have been seen by the second stage suspension sensors, and none of them are above the sensor noise levels of the penultimate stage. Therefore, we cannot eliminate the possibility of transient noise in the detectors originating in the intermediate stages of the suspension below the sensing noise.

13.
Int J Oral Maxillofac Surg ; 45(8): 980-4, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26993104

RESUMEN

The use of maxillomandibular fixation (MMF) screws in orthognathic surgery has become common in recent years. The risk of injury to adjacent roots with their placement in this population has not been studied extensively. The aim of this study was to review the incidence and consequences of root contact/injury in patients undergoing orthognathic surgery. A retrospective analysis of the treatment and radiographic records of patients who underwent orthognathic surgery between January 2013 and September 2014 at a university in Kentucky, USA was performed. The mean number of screws used was correlated to the mean number of roots affected using Spearman's test, set to a level of significance of 5%. Of 125 patients who underwent orthognathic surgery, 15 (12%) had evidence of root contact. Subsequent radiographs showed resolution of the bone defects. There was no clinical evidence of pulpal necrosis or pain during follow-up. The average number of screws used was 3.14±0.35 per patient, with an average of 0.17±0.52 root contacts per patient. There was no correlation between the number of screws used and the number of roots injured (P=0.279). Based on these results, MMF screws can safely be used to establish interim fixation during orthognathic surgery. Caution should be taken during placement to avoid direct injury to the roots of teeth.


Asunto(s)
Tornillos Óseos/efectos adversos , Raíz del Diente/lesiones , Adolescente , Adulto , Anciano , Tornillos Óseos/estadística & datos numéricos , Femenino , Humanos , Técnicas de Fijación de Maxilares/instrumentación , Masculino , Persona de Mediana Edad , Cirugía Ortognática , Estudios Retrospectivos , Estadísticas no Paramétricas , Raíz del Diente/diagnóstico por imagen , Resultado del Tratamiento , Adulto Joven
16.
J Dermatolog Treat ; 27(2): 136-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26447167

RESUMEN

Generalised granuloma annulare (GGA) is a significant cosmetic issue for patients but evidence is lacking to guide optimum treatment. We reviewed our patients with GGA treated with PUVA and narrowband UVB (NBUVB). A telephone questionnaire obtained the patients' perspective in terms of treatment response, remission and overall satisfaction. Twenty patients, all female, were treated. Twelve patients had 15 courses of PUVA therapy (10 oral, 5 bath PUVA) and 10 had 12 courses of NB UVB (two patients had both). There was clearance or minimal residual disease (MRD) on clinical examination in eight of 12 patients after PUVA. Remission was for six months in seven patients extending to one year or more in five patients. Nine patients were contactable after PUVA therapy. They reported their satisfaction as excellent (n = 1), very good (n = 2) or good (n = 4), and two were disappointed. There was clearance or MRD in seven patients treated with NBUVB. Remission was for six months in at least three patients and greater than 1 year in at least 2 patients. Eight patients were contactable and reported satisfaction as excellent (n = 1) or good (n = 5) and two were disappointed. PUVA and NBUVB were effective in at least half of patients and they achieved satisfactory remission. Patients' perceptions of the improvement after phototherapy were lower compared with their dermatologists' assessment.


Asunto(s)
Granuloma Anular/terapia , Terapia PUVA/métodos , Terapia Ultravioleta/métodos , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Rayos Ultravioleta , Adulto Joven
17.
Cell Death Differ ; 22(12): 1995-2005, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25929858

RESUMEN

Hearing loss and balance disorders affect millions of people worldwide. Sensory transduction in the inner ear requires both mechanosensory hair cells (HCs) and surrounding glia-like supporting cells (SCs). HCs are susceptible to death from aging, noise overexposure, and treatment with therapeutic drugs that have ototoxic side effects; these ototoxic drugs include the aminoglycoside antibiotics and the antineoplastic drug cisplatin. Although both classes of drugs are known to kill HCs, their effects on SCs are less well understood. Recent data indicate that SCs sense and respond to HC stress, and that their responses can influence HC death, survival, and phagocytosis. These responses to HC stress and death are critical to the health of the inner ear. Here we have used live confocal imaging of the adult mouse utricle, to examine the SC responses to HC death caused by aminoglycosides or cisplatin. Our data indicate that when HCs are killed by aminoglycosides, SCs efficiently remove HC corpses from the sensory epithelium in a process that includes constricting the apical portion of the HC after loss of membrane integrity. SCs then form a phagosome, which can completely engulf the remaining HC body, a phenomenon not previously reported in mammals. In contrast, cisplatin treatment results in accumulation of dead HCs in the sensory epithelium, accompanied by an increase in SC death. The surviving SCs constrict fewer HCs and display impaired phagocytosis. These data are supported by in vivo experiments, in which cochlear SCs show reduced capacity for scar formation in cisplatin-treated mice compared with those treated with aminoglycosides. Together, these data point to a broader defect in the ability of the cisplatin-treated SCs, to preserve tissue health in the mature mammalian inner ear.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Sáculo y Utrículo/citología , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Cisplatino/farmacología , Femenino , Masculino , Ratones , Ratones Endogámicos CBA , Microscopía Confocal , Neomicina/farmacología , Fagocitosis/efectos de los fármacos , Sáculo y Utrículo/efectos de los fármacos , Sáculo y Utrículo/metabolismo
18.
Nat Commun ; 6: 6730, 2015 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-25823949

RESUMEN

Recently discovered relativistic spin torques induced by a lateral current at a ferromagnet/paramagnet interface are a candidate spintronic technology for a new generation of electrically controlled magnetic memory devices. The focus of our work is to experimentally disentangle the perceived two model physical mechanisms of the relativistic spin torques, one driven by the spin-Hall effect and the other one by the inverse spin-galvanic effect. Here, we show a vector analysis of the torques in a prepared epitaxial transition-metal ferromagnet/semiconductor-paramagnet single-crystal structure by means of the all-electrical ferromagnetic resonance technique. By choice of our structure in which the semiconductor paramagnet has a Dresselhaus crystal inversion asymmetry, the system is favourable for separating the torques due to the inverse spin-galvanic effect and spin-Hall effect mechanisms into the field-like and antidamping-like components, respectively. Since they contribute to distinct symmetry torque components, the two microscopic mechanisms do not compete but complement each other in our system.

19.
Artículo en Inglés | MEDLINE | ID: mdl-24630161

RESUMEN

OBJECTIVE: This investigation tested the hypothesis that systemic inflammatory responses would be attenuated by minimizing the oral microbial burden in patients with moderate to severe periodontitis. STUDY DESIGN: Patients (n = 73) scheduled for full-mouth extractions were categorized as case type I/II (gingivitis/mild periodontitis) or case type III/IV (moderate/severe periodontitis). Serum levels of acute phase proteins (APPs) and immunoglobulin G (IgG) antibody were assessed at baseline and through 1 year after extraction. RESULTS: At baseline, the levels of multiple APPs (e.g., fibrinogen, C-reactive protein) and antibodies to periodontal pathogens were significantly higher with case type III/IV vs I/II. These differences were sustained 12 months after extractions for most APPs. CONCLUSIONS: The results demonstrated that removal of disease by full-mouth extraction of teeth altered the overall burden of challenge to the host. Continued elevation in various APPs in the III/IV group suggested a potential underlying constitutive difference in systemic response characteristics of this population.


Asunto(s)
Periodontitis/cirugía , Síndrome de Respuesta Inflamatoria Sistémica/sangre , Extracción Dental , Proteínas de Fase Aguda/metabolismo , Adulto , Anciano , Biomarcadores/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina G/sangre , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/cirugía
20.
Indian J Cancer ; 51(4): 502-5, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-26842177

RESUMEN

Oral squamous cell carcinoma (OSCC) is one of the most debilitating cancers in the world and while its causes have been heavily researched, the outcome remains grim. Most of these cancers are identified in the late stage and as a result treatment options are limited. Therefore, researchers have focused their efforts on recognizing and identifying dysplastic tissue that has an increased chance of progressing to cancer. Research has begun to look at cell cycle dysfunctions and in particular, aberrant protein functions as a way of identifying the cellular mechanism at fault. The overexpression of a group of regulatory proteins called cyclins has been demonstrated in many types of dysplasia and carcinomas. Although researchers have identified several different types of cyclins as potential culprits, we chose to focus our study primarily on the overexpression of cyclin A. While most research on oral dysplasia and OSCC has been focused on cyclin D, studies have been done on cyclin A. While the etiology of oral dysplasia/SCC appears to be multifactorial, we chose to compare our results with those of similar studies performed across the globe. The social factors, such as the increased use of tobacco that may have contributed to our results, were compared with similar studies performed in Europe and Asia. While our results were remarkably similar and demonstrated a link between the overexpression of cyclin A in oral dysplasia, there exists some differences and thus may require a multicenter, longitudinal study.


Asunto(s)
Carcinoma de Células Escamosas/química , Ciclina A/análisis , Mucosa Bucal/química , Mucosa Bucal/patología , Neoplasias de la Boca/química , Humanos
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