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INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic led to hospitals in the UK substituting face-to-face (FtF) clinics with virtual clinic (VC) appointments. We evaluated the use of virtual two-week wait (2-ww) lower gastrointestinal (LGI) clinic appointments, conducted using telephone calls at a district general hospital in England. METHODS: Patients undergoing index outpatient 2-ww LGI clinic assessment between 1 June 2019 and 31 October 2019 (FtF group) and 1 June 2020 and 31 October 2020 (VC group) were identified. Relevant data were obtained using electronic patient records. Compliance with national cancer waiting time targets was assessed. Environmental and financial impact analyses were performed. RESULTS: In total, 1,531 patients were analysed (median age=70, male=852, 55.6%). Of these, 757 (49.4%) were assessed virtually via telephone; the remainder were seen FtF (n=774, 50.6%). Ninety-two (6%, VC=44, FtF=48) patients had malignant pathology and 64 (4.2%) had colorectal cancer (CRC); of these, 46 (71.9%, VC=26, FtF=20) underwent treatment with curative intent. The median waiting times to index appointment, investigation and diagnosis were significantly lower following VC assessment (p<0.001). The cancer detection rates (p=0.749), treatments received (p=0.785) and median time to index treatment for CRC patients (p=0.156) were similar. A significantly higher proportion of patients were seen within two weeks of referral in the VC group (p<0.001). VC appointments saved patients a total of 9,288 miles, 0.7 metric tonnes of CO2 emissions and £7,482.97. Taxpayers saved £80,242.00 from VCs. No formal complaints were received from patients or staff in the VC group. CONCLUSION: Virtual 2-ww LGI clinics were effective, safe and were associated with tangible environmental and financial benefits.
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COVID-19 , Neoplasias Colorrectales , Humanos , Masculino , Anciano , Derivación y Consulta , COVID-19/epidemiología , Teléfono , Citas y Horarios , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/terapiaAsunto(s)
Enfermedades de los Bovinos , Industria Lechera , Animales , Bovinos , Femenino , LactanciaRESUMEN
High levels of supplementation with cereal increases production rates in cattle but can increase incidence of disease, ranging from mild indigestion to acute ruminal acidosis and death. Therefore, there is motivation to determine biological markers which can be used to identify whether animals have been, or are being fed, sufficient or excessive cereals. This study aimed to describe light microscopic findings from animals being fed diverse dietary cereal proportions and to test the performance of a novel rumen epithelial scoring system. Rumen wall tissue samples were obtained from the abattoir from 195 cattle from 11 Scottish farms and processed for histological examination. Light microscopic examination was used to characterise ruminal epithelial response to dietary challenge. Secondary objectives included describing the distribution of immune-related cells in bovine ruminal epithelium and assessing the use of a modified Elastin Martius Scarlet Blue stain (EMSB) for histological examination of the rumen epithelium. Cells staining positive for cluster of differentiation 3 were distributed mainly in the lower layers of the stratum basale and were found in higher densities in animals offered lower cereal proportion diets. Cells staining positive for major histocompatibility complex class 2 (MHCII) were most common in perivascular locations and in the junction between the lower stratum basale and the propria-submucosa. The density of MHCII positive staining cells was higher in animals on lower cereal diets. The level of supplementation with cereal was also associated with the thickness of the stratum corneum (SCT) and stratum granulosum (SGT), the integrity of the stratum corneum and sloughing of cornified cells. There were no advantages in using EMSB stain over haematoxylin and eosin (H&E) in this scoring system. We concluded that a scoring system that included only SCT, SGT and a measure of the loss of appearance of intercellular space allowed differentiation of groups of animals according to the level of cereal supplementation.
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Acidosis , Enfermedades de los Bovinos , Acidosis/veterinaria , Alimentación Animal/análisis , Animales , Bovinos , Enfermedades de los Bovinos/etiología , Dieta/veterinaria , Grano Comestible , Epitelio , Concentración de Iones de Hidrógeno , Rumen/fisiologíaRESUMEN
It is important that clinical radiologists understand and appreciate the minimally invasive surgery (MIS) options available to surgeons. Operative technologies are constantly evolving, and accurate, informed interpretation of clinical imaging is essential for optimum surgical management. Concurrent advancements in both MIS and radiological staging have certainly improved treatment decisions and outcomes. This article outlines the history, current concepts, evolving techniques, and future prospects of MIS as it pertains to colorectal cancer surgery.
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Neoplasias Colorrectales/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos , Neoplasias Colorrectales/diagnóstico por imagen , Neoplasias Colorrectales/patología , Humanos , Procedimientos Quirúrgicos RobotizadosRESUMEN
Claw horn lesions (CHL) are the result of a failing of the functional anatomy of the hoof in dairy cows. The digital cushion is understood to be a vital structure in the prevention of CHL. Claw horn lesions have previously been shown to lead to pathological change to the pedal bone; however, their effects on the digital cushion are unknown. The primary aim of this study was to examine associations between the history of CHL through an animal's life and the structure of the digital cushion at slaughter using magnetic resonance imaging. The retrospective cohort study resulted in the scanning of 102 pairs of hindfeet, collected from adult Holstein dairy cows culled from a research herd, using a 3-Tesla research-grade magnetic resonance imaging scanner. Volume and fat measurements were calculated for each digital cushion within each claw from a modified Dixon Quant sequence. Animal-level variables were constructed around the animals' lactating lifetime, with lameness scores and body condition score collected at least every 2 wk. The combined volume of digital cushion in the lateral claws was used as the outcome variable in multivariable linear models. The volume of the digital cushion was negatively associated with the number of lameness events or CHL recorded. Furthermore, animals with body condition score >3, culled later in lactation, or of a greater body weight were more likely to have a higher volume of digital cushion in the lateral claws. We propose that the observations made in the current study are the effects of a range of factors broadly associated with genetic, developmental, and disease-related inputs. Our understanding of how we can select for genetically more robust animals and how we can precondition the hoof before first calving needs to be improved to reduce the risk of future CHL in adult dairy cattle. Furthermore, understanding optimal treatment regimens and their effect on hoof anatomy may reduce the recurrence of CHL in the current lactation and future lactations.
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Enfermedades de los Bovinos , Enfermedades del Pie , Animales , Bovinos , Femenino , Enfermedades del Pie/veterinaria , Lactancia , Cojera Animal , Imagen por Resonancia Magnética/veterinaria , Estudios RetrospectivosRESUMEN
Despite significant reductions in malaria transmission across Africa since 2000, progress is stalling. This has been attributed to the development of insecticide resistance and behavioural adaptations in malaria vectors. Whilst insecticide resistance has been widely investigated, there is poorer understanding of the emergence, dynamics and impact of mosquito behavioural adaptations. We conducted a longitudinal investigation of malaria vector host choice over 3 years and resting behaviour over 4 years following a mass long-lasting insecticidal nets (LLINs) distribution in Tanzania. By pairing observations of mosquito ecology with environmental monitoring, we quantified longitudinal shifts in host-choice and resting behaviour that are consistent with adaptation to evade LLINs. The density of An. funestus s.l., declined significantly through time. In tandem, An. arabiensis and An. funestus s.l. exhibited an increased rate of outdoor relative to indoor resting; with An. arabiensis reducing the proportion of blood meals taken from humans in favour of cattle. By accounting for environmental variation, this study detected clear evidence of intra-specific shifts in mosquito behaviour that could be obscured in shorter-term or temporally-coarse surveys. This highlights the importance of mosquito behavioural adaptations to vector control, and the value of longer-term behavioural studies.
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Malaria/prevención & control , Malaria/transmisión , Animales , Anopheles/parasitología , Bovinos , Humanos , Resistencia a los Insecticidas , Mosquiteros Tratados con Insecticida , Insecticidas/uso terapéutico , Control de Mosquitos , Mosquitos Vectores/parasitología , TanzaníaRESUMEN
Sub-acute ruminal acidosis (SARA) can reduce the production efficiency and impair the welfare of cattle, potentially in all production systems. The aim of this study was to characterise measurable postmortem observations from divergently managed intensive beef finishing farms with high rates of concentrate feeding. At the time of slaughter, we obtained samples from 19 to 20 animals on each of 6 beef finishing units (119 animals in total) with diverse feeding practices, which had been subjectively classified as being high risk (three farms) or low risk (three farms) for SARA on the basis of the proportions of barley, silage and straw in the ration. We measured the concentrations of histamine, lipopolysaccharide (LPS), lactate and other short-chain fatty acids (SCFAs) in ruminal fluid, LPS and SCFA in caecal fluid. We also took samples of the ventral blind sac of the rumen for histopathology, immunohistopathology and gene expression. Subjective assessments were made of the presence of lesions on the ruminal wall, the colour of the lining of the ruminal wall and the shape of the ruminal papillae. Almost all variables differed significantly and substantially among farms. Very few pathological changes were detected in any of the rumens examined. The animals on the high-risk diets had lower concentrations of SCFA and higher concentrations of lactate and LPS in the ruminal fluid. Higher LPS concentrations were found in the caecum than the rumen but were not related to the risk status of the farm. The diameters of the stratum granulosum, stratum corneum and of the vasculature of the papillae, and the expression of the gene TLR4 in the ruminal epithelium were all increased on the high-risk farms. The expression of IFN-γ and IL-1ß and the counts of cluster of differentiation 3 positive and major histocompatibility complex class two positive cells were lower on the high-risk farms. High among-farm variation and the unbalanced design inherent in this type of study in the field prevented confident assignment of variation in the dependent variables to individual dietary components; however, the CP percentage of the total mixed ration DM was the factor that was most consistently associated with the variables of interest. Despite the strong effect of farm on the measured variables, there was wide inter-animal variation.
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Hordeum , Rumen , Alimentación Animal/análisis , Animales , Bovinos , Ciego , Dieta/veterinaria , Fermentación , Expresión Génica , Hordeum/genética , Concentración de Iones de Hidrógeno , Rumen/metabolismo , Ensilaje/análisisRESUMEN
The tricuspid leaflets coapt during systole to facilitate proper valve function and, thus, ensure efficient transport of deoxygenated blood to the lungs. Between their open state and closed state, the leaflets undergo large deformations. Quantification of these deformations is important for our basic scientific understanding of tricuspid valve function and for diagnostic or prognostic purposes. To date, tricuspid valve leaflet strains have never been directly quantified in vivo. To fill this gap in our knowledge, we implanted four sonomicrometry crystals per tricuspid leaflet and six crystals along the tricuspid annulus in a total of five sheep. In the beating ovine hearts, we recorded crystal coordinates alongside hemodynamic data. Once recorded, we used a finite strain kinematic framework to compute the temporal evolutions of area strain, radial strain, and circumferential strain for each leaflet. We found that leaflet strains were larger in the anterior leaflet than the posterior and septal leaflets. Additionally, we found that radial strains were larger than circumferential strains. Area strains were as large as 97% in the anterior leaflet, 31% in the posterior leaflet, and 31% in the septal leaflet. These data suggest that tricuspid valve leaflet strains are significantly larger than those in the mitral valve. Should our findings be confirmed they could suggest either that the mechanobiological equilibrium of tricuspid valve resident cells is different than that of mitral valve resident cells or that the mechanotransductive apparatus between the two varies. Either phenomenon may have important implications for the development of tricuspid valve-specific surgical techniques and medical devices.
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Corazón/fisiopatología , Contracción Miocárdica/fisiología , Válvula Tricúspide/fisiopatología , Animales , Fenómenos Biomecánicos , Hemodinámica , Ovinos , Estrés Mecánico , Sístole/fisiología , Factores de TiempoRESUMEN
INTRODUCTION: Surgical trainees are reporting barriers to training in gastrointestinal (GI) endoscopy. This snapshot survey aimed to gather data on variation in access to quality GI endoscopy training for Colorectal and Upper Gastrointestinal (GI) surgical trainees across the UK and Ireland. MATERIALS AND METHODS: An online 20-point survey was designed and distributed nationally to surgical trainee members of the Association of Surgeons in Training (ASiT), Dukes and The Roux Group (formerly Association of Upper Gastrointestinal Surgeons of Great Britain and Ireland Trainees). The survey was designed in collaboration with The Roux Group for Upper GI trainees and the Dukes' Club for Colorectal trainees. RESULTS: 218 responses were received, most with a Colorectal or Upper GI sub-specialty interest (colorectal 56.0%; upper GI surgery 25.7%). Only 28.6% of trainees attended a dedicated training endoscopy list at least once a week with 28.1% not attending any at all. Less than half of trainees reported having endoscopy formally timetabled on rotas (36.9%). Most trainees (88.0%) encountered difficulties in gaining endoscopy training including lack of available lists (77.2%), conflicting operative commitments (59.4%), preferential allocation of lists to gastroenterology trainees (57.9%) and resistance from endoscopy departmental leads (38.6%). Regarding JAG accreditation, 77.1% respondents felt it should be mandatory prior to CCT with 80.3% believing this would lead to better access to dedicated endoscopy training equivalent to gastroenterology trainees. 93.1% trainees felt that attaining JAG accreditation by surgical trainees was important to patient care. DISCUSSION: This study demonstrates significant barriers in accessing GI endoscopy training for general surgical trainees which urgently needs to be improved. In order to meet JAG training requirements for surgical trainees, a multifaceted collaborative approach from surgical and gastroenterology training bodies, local JAG trainers and the General Surgery SAC and JCST is required. This is to ensure that endoscopy is promoted and a robust model of training is successfully designed and delivered to general surgery trainees.
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Educación Médica/estadística & datos numéricos , Endoscopía Gastrointestinal/educación , Cirugía General/educación , Cirujanos/educación , Adulto , Competencia Clínica , Femenino , Humanos , Irlanda , Masculino , Estudios Prospectivos , Encuestas y Cuestionarios , Reino UnidoRESUMEN
Syncytial hepatitis (SHT) is an emerging viral disease of tilapia characterized by significant morbidity and mortality. This study aimed to establish the production-level risk factors associated with presence and severity of SHT. Production factors were analysed during multiple outbreaks of SHT that occurred between 2011 and 2013 on a single tilapia farm in Ecuador and compared with the year 2010 before the SHT outbreaks. Relative risks, t tests, modified Poisson and forward stepwise linear regression analyses were performed using EPIINFO™. Compared to other strains, Chitralada had an elevated risk of SHT [RR = 2.1 (95%CI 1.8-2.4)]. Excessive mortality associated with the presence (and severity) of SHT increased by 611 (365), 6,814 (5,768) and 388 (340) deaths per 100,000 fry when stocking density, dissolved oxygen and pond production cycles were raised by 1 fish/m2 , 1 mg/L and 1 cycle, respectively. Excessive mortality associated with the presence (and severity) of SHT decreased by 337 (258) and 1,354 (1,025) deaths per 100,000 when stocking weight and water temperature increased by 1 g and 1°C, respectively. Time (season and stocking year) was not significantly associated with SHT. This study shows that some production factors increase the risk incidence and severity of SHTon a farm.
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Acuicultura/métodos , Cíclidos/virología , Enfermedades de los Peces/virología , Hepatitis Viral Animal/epidemiología , Infecciones por Orthomyxoviridae/veterinaria , Animales , Cíclidos/genética , Brotes de Enfermedades/veterinaria , Ecuador , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/mortalidad , Células Gigantes/virología , Orthomyxoviridae , Factores de Riesgo , TemperaturaRESUMEN
The social media network Facebook™ was used to gather information on the occurrence and geographical distribution of dusky grouper dermatitis, a skin lesion affecting the dusky grouper, Epinephelus marginatus. Dusky grouper are common targets for spear fishermen in the Mediterranean and by monitoring spearfishing activity in Libyan waters, it was possible to document skin lesions from their entries on Facebook. Thirty-two Facebook accounts and 8 Facebook groups posting from 23 Libyan coastal cities provided a retrospective observational data set comprising a total of 382 images of dusky grouper caught by spearfishing between December 2011 and December 2015. Skin lesions were observable on 57/362 fish, for which images were of sufficient quality for analysis, giving a minimal prevalence for lesions of 15.75%. Only dusky grouper exceeding an estimated 40 cm total length exhibited lesions. The ability to collect useful data about the occurrence and geographical distribution of pathological conditions affecting wild fish using social media networks demonstrates their potential utility as a tool to support epidemiological studies and monitor the health of populations of aquatic animals. To our knowledge, this represents the first time that such an approach has been applied for assessing health in a wild population of fish.
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Lubina , Dermatitis/veterinaria , Monitoreo del Ambiente/métodos , Enfermedades de los Peces/diagnóstico , Medios de Comunicación Sociales , Animales , Dermatitis/clasificación , Dermatitis/diagnóstico , Dermatitis/epidemiología , Monitoreo del Ambiente/instrumentación , Enfermedades de los Peces/clasificación , Enfermedades de los Peces/epidemiología , Libia/epidemiología , Vigilancia de la Población , Estudios Retrospectivos , Medios de Comunicación Sociales/estadística & datos numéricosRESUMEN
Using transmission electron microscopy (TEM), the presented work expands on the ultrastructural findings of an earlier report on "syncytial hepatitis," a novel disease of tilapia (SHT). Briefly, TEM confirmed the presence of an orthomyxovirus-like virus within the diseased hepatocytes but not within the endothelium. This was supported by observing extracellular and intracellular (mostly intraendosomal), 60-100 nm round virions with a trilaminar capsid containing up to 7 electron-dense aggregates. Other patterns noted included enveloped or filamentous virions and virion-containing cytoplasmic membrane folds, suggestive of endocytosis. Patterns atypical for orthymyxovirus included the formation of syncytia and the presence of virions within the perinuclear cisternae (suspected to be the Golgi apparatus). The ultrastructural morphology of SHT-associated virions is similar to that previously reported for tilapia lake virus (TiLV). A genetic homology was investigated using the available reverse transcriptase polymerase chain reaction (RT-PCR) probes for TiLV and comparing clinically sick with clinically normal fish and negative controls. By RT-PCR analysis, viral nucleic acid was detected only in diseased fish. Taken together, these findings strongly suggest that a virus is causally associated with SHT, that this virus shares ultrastructural features with orthomyxoviruses, and it presents with partial genetic homology with TiLV (190 nucleotides).
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Enfermedades de los Peces/virología , Hepatitis Viral Animal/virología , Hepatocitos/virología , Infecciones por Orthomyxoviridae/veterinaria , Tilapia/virología , Virión/ultraestructura , Animales , Hepatitis Viral Animal/patología , Hepatocitos/patología , Hepatocitos/ultraestructura , Masculino , Microscopía Electrónica de Transmisión/veterinaria , Orthomyxoviridae/genética , Infecciones por Orthomyxoviridae/patología , Infecciones por Orthomyxoviridae/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinariaRESUMEN
In the period 2013-2015, wild dusky grouper, Epinephelus marginatus (Lowe), caught in Libyan coastal waters and ranging in size from 42 to 92 cm in total length, were observed to have distinctive skin lesions of unknown aetiology. Histopathologically, the lesions comprised a multifocal, unilateral or bilateral dermatitis, involving the epidermis, superficial dermis and scale pockets, and sometimes, in severe cases, the hypodermis. Severe lesions had marked epidermal spongiosis progressing to ulceration. Healing was observed in some fish. Bacteria and fungi could be isolated from severe lesions, although they were not seen histopathologically in early-stage lesions. By contrast, metazoan parasite eggs were observed in the dermis and epidermis of some fish with mild and moderate dermatitis. Unidentified gravid digenean trematode parasites carrying similar eggs were also seen within the blood vessels of the deep and superficial dermis. The cause of this distinctive condition, termed dusky grouper dermatitis (DGD), and its potential impact upon already threatened Mediterranean wild dusky grouper populations and upon cultured grouper more widely have yet to be established.
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Lubina , Dermatitis/veterinaria , Enfermedades de los Peces/patología , Animales , Dermatitis/epidemiología , Dermatitis/etiología , Dermatitis/patología , Especies en Peligro de Extinción , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/microbiología , Enfermedades de los Peces/parasitología , Libia/epidemiologíaRESUMEN
BACKGROUND: There is growing evidence that the widespread use of Long-Lasting Insecticidal Nets (LLINs) is prompting malaria vectors to shift their biting towards times and places where people are not protected, such as earlier in the evening and/or outdoors. It is uncertain whether these behavioural shifts are due to phenotypic plasticity and/or ecological changes within vector communities that favour more exophilic species, or involve genetic factors within vector species to limit their contact with LLINs. Possibly variation in the time and location of mosquito biting has a genetic basis, but as yet this phenomenon has received little investigation. Here we used a candidate gene approach to investigate whether polymorphisms in selected circadian clock genes could explain variation in the time and location of feeding (indoors versus outside) within a natural population of the major African malaria vector Anopheles arabiensis. METHODS: Host-seeking An. arabiensis were collected from two villages (Lupiro and Sagamaganga) in Tanzania by Human Landing Catch (HLC) technique. Mosquitoes were classified into phenotypes of "early" (7 pm-10 pm) or "late" biting (4 am -7 am), and host-seeking indoors or outdoors. In these samples we genotyped 34 coding SNPs in 8 clock genes (PER, TIM, CLK, CYC, PDP1, VRI, CRY1, and CRY2), and tested for associations between these SNPs and biting phenotypes. SNPs in 8 mitochondrial genes (ATP6, ATP8, COX1, COX2, COX3, ND3, ND5 and CYTB) were also genotyped to test population subdivision within An. arabiensis. RESULTS: The candidate clock genes exhibited polymorphism within An. arabiensis, but it was unrelated to variation in the timing and location of their biting activity. However, there was evidence of strong genetic structure within An. arabiensis populations in association with the TIM, which was unrelated to geographic distance. Substructure within An. arabiensis was also detected using mitochondrial markers. CONCLUSIONS: The variable timing and location of biting in An. arabiensis could not be linked to candidate clock genes that are known to influence behaviour in other Diptera. This finding does not rule out the possibility of a genetic basis to biting behaviour in this malaria vector, but suggests these are complex phenotypes that require more intensive ecological, neuronal and genomic analyses to understand.
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Anopheles/genética , Anopheles/fisiología , Relojes Circadianos/genética , Conducta Alimentaria , Insectos Vectores , Polimorfismo de Nucleótido Simple , Animales , Genotipo , Técnicas de Genotipaje , Humanos , Tanzanía , Factores de TiempoRESUMEN
The public health threat posed by zoonotic Plasmodium knowlesi appears to be growing: it is increasingly reported across South East Asia, and is the leading cause of malaria in Malaysian Borneo. Plasmodium knowlesi threatens progress towards malaria elimination as aspects of its transmission, such as spillover from wildlife reservoirs and reliance on outdoor-biting vectors, may limit the effectiveness of conventional methods of malaria control. The development of new quantitative approaches that address the ecological complexity of P. knowlesi, particularly through a focus on its primary reservoir hosts, will be required to control it. Here, we review what is known about P. knowlesi transmission, identify key knowledge gaps in the context of current approaches to transmission modelling, and discuss the integration of these approaches with clinical parasitology and geostatistical analysis. We highlight the need to incorporate the influences of fine-scale spatial variation, rapid changes to the landscape, and reservoir population and transmission dynamics. The proposed integrated approach would address the unique challenges posed by malaria as a zoonosis, aid the identification of transmission hotspots, provide insight into the mechanistic links between incidence and land use change and support the design of appropriate interventions.
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Ecología/tendencias , Macaca/parasitología , Malaria/transmisión , Enfermedades de los Monos/parasitología , Plasmodium knowlesi , Zoonosis/parasitología , Animales , Asia Sudoriental/epidemiología , Culicidae/parasitología , Demografía , Reservorios de Enfermedades/parasitología , Actividades Humanas , Humanos , Insectos Vectores/parasitología , Malaria/epidemiología , Malaria/parasitología , Modelos Biológicos , Enfermedades de los Monos/epidemiología , Enfermedades de los Monos/transmisión , Plasmodium knowlesi/patogenicidad , Plasmodium knowlesi/fisiología , Factores de Riesgo , Zoonosis/epidemiología , Zoonosis/transmisiónRESUMEN
Streptococcus agalactiae infections in fish are predominantly caused by beta-haemolytic strains of clonal complex (CC) 7, notably its namesake sequence type (ST) 7, or by non-haemolytic strains of CC552, including the globally distributed ST260. In contrast, CC23, including its namesake ST23, has been associated with a wide homeothermic and poikilothermic host range, but never with fish. The aim of this study was to determine whether ST23 is virulent in fish and to identify genomic markers of fish adaptation of S. agalactiae. Intraperitoneal challenge of Nile tilapia, Oreochromis niloticus (Linnaeus), showed that ST260 is lethal at doses down to 10(2) cfu per fish, whereas ST23 does not cause disease at 10(7) cfu per fish. Comparison of the genome sequence of ST260 and ST23 with those of strains derived from fish, cattle and humans revealed the presence of genomic elements that are unique to subpopulations of S. agalactiae that have the ability to infect fish (CC7 and CC552). These loci occurred in clusters exhibiting typical signatures of mobile genetic elements. PCR-based screening of a collection of isolates from multiple host species confirmed the association of selected genes with fish-derived strains. Several fish-associated genes encode proteins that potentially provide fitness in the aquatic environment.
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Cíclidos , Enfermedades de los Peces/microbiología , Genoma Bacteriano , Infecciones Estreptocócicas/veterinaria , Streptococcus agalactiae/patogenicidad , Animales , Bovinos , ADN Bacteriano/química , ADN Bacteriano/aislamiento & purificación , Sitios Genéticos/genética , Humanos , Filogenia , Phocidae/microbiología , Pase Seriado/veterinaria , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/clasificación , Streptococcus agalactiae/genética , VirulenciaRESUMEN
The rhythm of life on earth is shaped by seasonal changes in the environment. Plants and animals show profound annual cycles in physiology, health, morphology, behaviour and demography in response to environmental cues. Seasonal biology impacts ecosystems and agriculture, with consequences for humans and biodiversity. Human populations show robust annual rhythms in health and well-being, and the birth month can have lasting effects that persist throughout life. This review emphasizes the need for a better understanding of seasonal biology against the backdrop of its rapidly progressing disruption through climate change, human lifestyles and other anthropogenic impact. Climate change is modifying annual rhythms to which numerous organisms have adapted, with potential consequences for industries relating to health, ecosystems and food security. Disconcertingly, human lifestyles under artificial conditions of eternal summer provide the most extreme example for disconnect from natural seasons, making humans vulnerable to increased morbidity and mortality. In this review, we introduce scenarios of seasonal disruption, highlight key aspects of seasonal biology and summarize from biomedical, anthropological, veterinary, agricultural and environmental perspectives the recent evidence for seasonal desynchronization between environmental factors and internal rhythms. Because annual rhythms are pervasive across biological systems, they provide a common framework for trans-disciplinary research.
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Ecosistema , Abastecimiento de Alimentos , Periodicidad , Estaciones del Año , Agricultura , Animales , Biodiversidad , Cambio Climático , Humanos , PlantasRESUMEN
BACKGROUND: Understanding mosquito resting behaviour is important for the control of vector-borne diseases, but this remains a challenge because of the paucity of efficient sampling tools. We evaluated two novel sampling methods in the field: the Sticky Resting Box (SRB) and the Resting Bucket trap (RBu) to test their efficiency for sampling malaria vectors resting outdoors and inside houses in rural Tanzania. The performance of RBu and SRB was compared outdoors, while indoors SRB were compared with the Back Pack Aspiration method (BP). Trapping was conducted within 4 villages in the Kilombero Valley, Tanzania over 14 nights. On each night, the performance for collecting Anopheles vectors and Culicinae was compared in 4 households by SRB and RBu outdoors and by SRB or fixed-time Back Pack aspirator in 2 of the 4 focal households indoors. FINDINGS: A total of 619 Anopheles gambiae s.l., 224 Anopheles funestus s.l. and 1737 Culicinae mosquitoes were captured. The mean abundance of An. arabiensis and An. funestus s.l. collected with SRB traps inside and outdoors was significantly lower than with BP or RBu. The SRB however, outperformed BP aspiration for collection of Culicinae indoors. CONCLUSIONS: Of the methods trialled indoors (BP and SRB), BP was the most effective, whilst outdoors RBu performed much better than SRB. However, as SRB can passively sample mosquitoes over a week they could provide an alternative to the RBu where daily monitoring is not possible.