RESUMEN
BACKGROUND: Patient delays at the point of their discharge account for more than half a million additional bed days every year in Scotland, United Kingdom. Bottlenecks in discharge medication dispensing contribute to such delays. AIM: To test whether the discharge process could be made more time-efficient by utilising community pharmacy supply of medicines on the day of discharge, rather than hospital pharmacy supply. SETTING: Glasgow Royal Infirmary, Scotland. DEVELOPMENT: Local community pharmacy staff received training and communication about each patient discharge. Pharmacies could access an immediate discharge letter (IDL) on a shared electronic record. The existing pandemic law allowed medication dispensing from this IDL, without a prescription. IMPLEMENTATION: The programme was implemented from June to November 2020, across three Plan-Do-Study-Act (PDSA) cycles. Comparisons were made between the new community pharmacy model and standard hospital model. EVALUATION: Across three PDSA cycles, in total 335 patients had community pharmacy supply compared to 376 patients eligible for hospital pharmacy supply. The median time taken from creation of the IDL to final completion was significantly lower in the new community pharmacy model compared to the hospital pharmacy model; 154 min (interquartile range (IQR) 82-272 min) vs 296 min (IQR 197-1281 min) p value < 0.000 CONCLUSION: A community pharmacy supply model compared to a standard hospital pharmacy model resulted in a median time saving of 142 min per patient. Such a time saving has the potential to deliver a transformational change in patient flow and free up hospital pharmacy staff to deliver other clinical interventions.
Asunto(s)
Servicios Comunitarios de Farmacia , Farmacias , Humanos , Alta del Paciente , Mejoramiento de la Calidad , Farmacéuticos , HospitalesRESUMEN
BACKGROUND: Early-stage oral squamous cell carcinoma (OSCC) patients have a one-in-four risk of regional metastasis (LN+), which is also the most significant prognostic factor for survival. As there are no validated biomarkers for predicting LN+ in early-stage OSCC, elective neck dissection often leads to over-treatment and under-treatment. We present a machine-learning-based model using the quantitative nuclear phenotype of cancer cells from the primary tumor to predict the risk of nodal disease. METHODS AND FINDINGS: Tumor specimens were obtained from 35 patients diagnosed with primary OSCC and received surgery with curative intent. Of the 35 patients, 29 had well (G1) or moderately (G2) differentiated tumors, and six had poorly differentiated tumors. From each, two consecutive sections were stained for hematoxylin & eosin and Feulgen-thionin staining. The slides were scanned, and images were processed to curate nuclear morphometric features for each nucleus, measuring nuclear morphology, DNA amount, and chromatin texture/organization. The nuclei (n = 384,041) from 15 G1 and 14 G2 tumors were randomly split into 80% training and 20% test set to build the predictive model by using Random Forest (RF) analysis which give each tumor cell a score, NRS. The area under ROC curve (AUC) was 99.6% and 90.7% for the training and test sets, respectively. At the cutoff score of 0.5 as the median NRS of each region of interest (n = 481), the AUC was 95.1%. We then developed a patient-level model based on the percentage of cells with an NRS ≥ 0.5. The prediction performance showed AUC of 97.7% among the 80% (n = 23 patient) training set and with the cutoff of 61% positive cells achieved 100% sensitivity and 91.7% specificity. When applying the 61% cutoff to the 20% test set patients, the model achieved 100% accuracy. CONCLUSIONS: Our findings may have a clinical impact with an easy, accurate, and objective biomarker from routine pathology tissue, providing an unprecedented opportunity to improve neck management decisions in early-stage OSCC patients.
Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Núcleo Celular/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Anciano , Femenino , Humanos , Aprendizaje Automático , Masculino , Persona de Mediana Edad , Carcinoma de Células Escamosas de Cabeza y Cuello/genéticaRESUMEN
BACKGROUND: DNA-image cytometry (DNA-ICM) is able to detect gross alterations of cellular DNA-content representing aneuploidy, a biomarker of malignancy. A Health Canada-approved DNA-ICM system, ClearCyte® in combination with a cytopathologist's review, has demonstrated high sensitivity (89%) and specificity (97%) in identifying high-grade oral lesions. The study objective was to create an improved automated algorithm (iClearcyte) and test its robustness in differentiating high grade from benign reactive oral lesions without a cytopathologist's input. METHODS: A set of 214 oral brushing samples of oral cancer (n = 92), severe dysplasia (n = 20), reactive lesions (n = 52), and normal samples (n = 50) were spun down onto slides and stained using Feulgen-Thionin reaction. Following ClearCyte® scan, nuclear features were calculated, and nuclei categorized into "diploid," "hyperdiploid," "tetraploid," and "aneuploid" DNA ploidy groups by the ClearCyte® software. The samples were randomized into training and test sets (70:30) based on patient's age, sex, tobacco use, and lesion site risk. The training set was used to create a new algorithm which was then validated using the remaining samples in the test set, where sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. RESULTS: The proposed iClearCyte algorithm (>1 "aneuploid" cell or ≥ 1.7% combined "hyperdiploid" and "tetraploid" nuclei frequency) identified high-grade samples with sensitivity, specificity, PPV, and NPV of 100.0%, 86.7%, 89.7%, and 100.0%, respectively, in the test set. CONCLUSION: The iClearCyte test has potential to serve as a robust non-invasive automated oral cancer screening tool promoting early oral cancer detection and decreasing the number of unnecessary invasive biopsies.
Asunto(s)
Citometría de Imagen , Neoplasias de la Boca , Algoritmos , Aneuploidia , Canadá , ADN , ADN de Neoplasias , Humanos , Neoplasias de la Boca/diagnóstico , Neoplasias de la Boca/genéticaRESUMEN
SCOPE: The aim of this study was to identify if specific regions of the human genome were sensitive to folate status by displaying changes in their DNA methylation patterns in response to continued folic acid supplementation during pregnancy. METHODS AND RESULTS: Samples (n = 119) from a previous randomised controlled trial in pregnancy were used to compare the DNA methylation profiles of the same woman pre- versus post-folic acid intervention. Candidate genes were identified from the literature and a pilot genome wide screen of six women (three from each of the folic acid and placebo arms of the trial). We did not observe consistent DNA methylation changes in response to folic acid intervention at any of our candidate genes (RASA4, DHFR, DHFR2, RASSF1A, EIF2C3, ATPF1). We did identify a 40% decrease in DNA methylation at the RASA4 promoter correlating with a 3.5-fold increase in its mRNA abundance in an in vitro cell culture model. CONCLUSION: Continued folic acid intervention over a 22-week period did not appear to significantly influence the DNA methylation status of six candidate genes in blood samples of women compared to placebo. However, DNA methylation may play a role in the gene expression control of the RASA4 gene.
Asunto(s)
Metilación de ADN , Suplementos Dietéticos , Ácido Fólico/administración & dosificación , Femenino , Células HEK293 , Humanos , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Regiones Promotoras Genéticas , Proteínas Activadoras de ras GTPasa/genéticaRESUMEN
Breast cancer is the leading cause of cancer-related deaths among women worldwide. We investigated whether changes in large-scale DNA organization (LDO) of tumor epithelial nuclei are an indicator of the aggressiveness of the tumor. We tested our algorithm on a set of 172 duplicates TMA cores samples coming from 95 breast cancer patients. Thirty-five patients died of breast cancer, and 60 were still alive 10 years after surgery. Duplicates cores were used to create training and test set. The TMA slides were stained with Feulgen-thionin and imaged using our in-house high-resolution Imaging system. Automated segmentation of cell nuclei followed by manual selection of intact, in-focus nuclei resulted in an average of 50 cell nuclei per sample available for analysis. Using forward stepwise linear discriminant analysis, a combination of six features that combined linearly gave the best discrimination between the two groups of cells: cells collected from 'deceased' patients TMA specimens and cells collected from "survivors" patients TMA specimens. Five of these features measure the spatial organization of DNA chromatin. The resulting canonical score is named cell LDO score. A patient LDO score, percentage of cell nuclei with a cell LDO score higher than a predefined cutoff value, was processed for the specimens in the test set, and a cutoff value was defined to classify patients with a low or a high LDO score. Using this binary test, 82.1% of patients were correctly classified are "deceased" or "survivors," with a specificity of 79% and a sensitivity of 88%. The relative risk of death of an individual with a high LDO score was nine times higher than for a patient with a low LDO score. When testing the combination of LDO score, node status, histological grade, and tumor grade to predict breast cancer survival, LDO was the most significant predictor. LDO classification was also highly associated with survival for only grade 1 and 2 patients as well as for only grade 3 patients. Our result confirms the potential of LDO to measure phenotypic changes associated with more aggressive disease and could be evaluated to identify patients more likely to benefit from adjuvant therapies.
Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/mortalidad , ADN de Neoplasias/ultraestructura , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Neoplasias de la Mama/patología , Estudios de Cohortes , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Análisis de SupervivenciaRESUMEN
Hyalomma Koch, 1844 are ixodid ticks that infest mammals, birds and reptiles, to which 27 recognized species occur across the Afrotropical, Palearctic and Oriental regions. Despite their medical and veterinary importance, the evolutionary history of the group is enigmatic. To investigate various taxonomic hypotheses based on morphology, and also some of the mechanisms involved in the diversification of the genus, we sequenced and analysed data derived from two mtDNA fragments, three nuclear DNA genes and 47 morphological characters. Bayesian and Parsimony analyses based on the combined data (2242 characters for 84 taxa) provided maximum resolution and strongly supported the monophyly of Hyalomma and the subgenus Euhyalomma Filippova, 1984 (including H. punt Hoogstraal, Kaiser and Pedersen, 1969). A predicted close evolutionary association was found between morphologically similar H. dromedarii Koch, 1844, H. somalicum Tonelli Rondelli, 1935, H. impeltatum Schulze and Schlottke, 1929 and H. punt, and together they form a sister lineage to H. asiaticum Schulze and Schlottke, 1929, H. schulzei Olenev, 1931 and H. scupense Schulze, 1919. Congruent with morphological suggestions, H. anatolicum Koch, 1844, H. excavatum Koch, 1844 and H. lusitanicum Koch, 1844 form a clade and so also H. glabrum Delpy, 1949, H. marginatum Koch, 1844, H. turanicum Pomerantzev, 1946 and H. rufipes Koch, 1844. Wide scale continental sampling revealed cryptic divergences within African H. truncatum Koch, 1844 and H. rufipes and suggested that the taxonomy of these lineages is in need of a revision. The most basal lineages in Hyalomma represent taxa currently confined to Eurasia and molecular clock estimates suggest that members of the genus started to diverge approximately 36.25 million years ago (Mya). The early diversification event coincides well with the collision of the Indian and Eurasian Plates, an event that was also characterized by large scale faunal turnover in the region. Using S-Diva, we also propose that the closure of the Tethyan seaway allowed for the genus to first enter Africa approximately 17.73Mya. In concert, our data supports the notion that tectonic events and large scale global changes in the environment contributed significantly to produce the rich species diversity currently found in the genus Hyalomma.
Asunto(s)
Evolución Biológica , Ixodidae/clasificación , Animales , Secuencia de Bases , Teorema de Bayes , Cambio Climático , ADN/química , ADN/aislamiento & purificación , ADN/metabolismo , Complejo IV de Transporte de Electrones/clasificación , Complejo IV de Transporte de Electrones/genética , Femenino , Variación Genética , Histonas/clasificación , Histonas/genética , Ixodidae/anatomía & histología , Filogenia , ARN Ribosómico 16S/clasificación , ARN Ribosómico 16S/genética , ARN Ribosómico 28S/clasificación , ARN Ribosómico 28S/genéticaRESUMEN
BACKGROUND: Rickettsiae are obligate intracellular bacteria responsible for many febrile syndromes around the world, including in sub-Saharan Africa. Vectors of these pathogens include ticks, lice, mites and fleas. In order to assess exposure to flea-associated Rickettsia species in Madagascar, human and small mammal samples from an urban and a rural area, and their associated fleas were tested. RESULTS: Anti-typhus group (TGR)- and anti-spotted fever group rickettsiae (SFGR)-specific IgG were detected in 24 (39%) and 21 (34%) of 62 human serum samples, respectively, using indirect ELISAs, with six individuals seropositive for both. Only two (2%) Rattus rattus out of 86 small mammals presented antibodies against TGR. Out of 117 fleas collected from small mammals, Rickettsia typhi, a TGR, was detected in 26 Xenopsylla cheopis (24%) collected from rodents of an urban area (n = 107), while two of these urban X. cheopis (2%) were positive for Rickettsia felis, a SFGR. R. felis DNA was also detected in eight (31%) out of 26 Pulex irritans fleas. CONCLUSIONS: The general population in Madagascar are exposed to rickettsiae, and two flea-associated Rickettsia pathogens, R. typhi and R. felis, are present near or in homes. Although our results are from a single district, they demonstrate that rickettsiae should be considered as potential agents of undifferentiated fever in Madagascar.
Asunto(s)
Ratas/microbiología , Rickettsia/genética , Rickettsia/aislamiento & purificación , Fiebre Maculosa de las Montañas Rocosas/microbiología , Fiebre Maculosa de las Montañas Rocosas/veterinaria , Enfermedades de los Roedores/microbiología , Siphonaptera/microbiología , Tifus Epidémico Transmitido por Piojos/microbiología , Tifus Epidémico Transmitido por Piojos/veterinaria , Adulto , Animales , Anticuerpos Antibacterianos/sangre , Femenino , Humanos , Insectos Vectores/microbiología , Madagascar , Masculino , Persona de Mediana Edad , Filogenia , Rickettsia/clasificación , Rickettsia/inmunología , Fiebre Maculosa de las Montañas Rocosas/sangre , Enfermedades de los Roedores/sangre , Musarañas/microbiología , Tifus Epidémico Transmitido por Piojos/sangre , Adulto JovenRESUMEN
The objectives of the study were to determine the species composition of ticks infesting white and black rhinoceroses in southern Africa as well as the conservation status of those tick species that prefer rhinos as hosts. Ticks were collected opportunistically from rhinos that had been immobilised for management purposes, and 447 white rhinoceroses (Ceratotherium simum) and 164 black rhinoceroses (Diceros bicornis) were sampled in South Africa, 61 black rhinos in Namibia, 18 white and 12 black rhinos in Zimbabwe, and 24 black rhinos in Zambia. Nineteen tick species were recovered, of which two species, Amblyomma rhinocerotis and Dermacentor rhinocerinus, prefer rhinos as hosts. A. rhinocerotis was collected only in the northeastern KwaZulu-Natal reserves of South Africa and is endangered, while D. rhinocerinus is present in these reserves as well as in the Kruger National Park and surrounding conservancies. Eight of the tick species collected from the rhinos are ornate, and seven species are regularly collected from cattle. The species present on rhinos in the eastern, moister reserves of South Africa were amongst others Amblyomma hebraeum, A. rhinocerotis, D. rhinocerinus, Rhipicephalus maculatus, Rhipicephalus simus and Rhipicephalus zumpti, while those on rhinos in the Karoo and the drier western regions, including Namibia, were the drought-tolerant species, Hyalomma glabrum, Hyalomma rufipes, Hyalomma truncatum and Rhipicephalus gertrudae. The species composition of ticks on rhinoceroses in Zambia differed markedly from those of the other southern African countries in that Amblyomma sparsum, Amblyomma tholloni and Amblyomma variegatum accounted for the majority of infestations.
Asunto(s)
Ixodidae/fisiología , Perisodáctilos/parasitología , Infestaciones por Garrapatas/veterinaria , Animales , Animales Salvajes/parasitología , Dermacentor/fisiología , Femenino , Ganado/parasitología , Masculino , Namibia/epidemiología , Rhipicephalus/fisiología , Sudáfrica/epidemiología , Especificidad de la Especie , Infestaciones por Garrapatas/epidemiología , Zambia/epidemiología , Zimbabwe/epidemiologíaRESUMEN
This survey of ixodid ticks was the first to compare the species composition and population dynamics of free-living ticks in intensive, sable antelope breeding enclosures, now commonplace in commercial wildlife ranching in South Africa, with those of multi-herbivore enclosures. The species composition, abundance and seasonal abundance of questing ixodid ticks on the vegetation in intensive breeding enclosures for sable antelope (Hippotragus niger), on which strategic tick control is practised, were compared with those of ticks in a multi-species herbivore enclosure surrounding the breeding enclosures in which no tick control is practised. A total of eight ixodid tick species were collected by drag-sampling the woodland and grassland habitats in each enclosure type monthly from July 2011 to July 2013. Rhipicephalus decoloratus, a potential vector of fatal tick-borne disease in sable antelopes, was the most abundant, accounting for 65.4% of the total number of ticks collected in the sable enclosures, whilst representing only 25.4% of number of ticks collected in the multi-species herbivore enclosure. Rhipicephalus decoloratus and R. evertsi evertsi were more abundant than R. appendiculatus (both p < 0.05) and Amblyomma hebraeum (p < 0.001 and p < 0.01, respectively). Rhipicephalus decoloratus larvae were collected throughout the year, with peak collections in November 2012 and October to December 2013 in the sable enclosures; and in April/May 2012 and February/April 2013 in the multi-species herbivore enclosure. More R. decoloratus were recovered in the second year than in the first year in the grassland habitat of the sable enclosures (V = 7.0, p < 0.05) possibly as a result of acaricide resistance. The apparent temporal over-abundance of R. decoloratus in sable antelope breeding enclosures, in the face of strategic tick control, is of concern and requires further investigation.
Asunto(s)
Antílopes/parasitología , Biodiversidad , Ixodidae/fisiología , Infestaciones por Garrapatas/veterinaria , Animales , Femenino , Ixodidae/clasificación , Ixodidae/crecimiento & desarrollo , Larva/clasificación , Larva/crecimiento & desarrollo , Ninfa/clasificación , Ninfa/crecimiento & desarrollo , Dinámica Poblacional , Estaciones del Año , Sudáfrica/epidemiología , Control de Ácaros y Garrapatas , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitologíaRESUMEN
Recent work has identified the presence of Anaplasma bovis, a tick-borne pathogen of cattle, in a previously undescribed species of tick collected from eastern rock sengis, Elephantulus myurus, in Limpopo Province, South Africa. These small insectivores are endemic to Africa and are important hosts of immature ticks, however, their role as reservoirs of tick-borne pathogens has not been investigated. In order to elucidate the role of sengis in the epidemiology of A. bovis, we screened the blood of 105 sengis from Limpopo Province, South Africa, for the presence of members of the genera Anaplasma and Ehrlichia by PCR. A total of 30/105 (28.6%) of individuals were infected with A. bovis, and nucleotide sequencing revealed the presence of a novel genetic variant of this pathogen. This represents the first evidence that sengis may be natural reservoir hosts of A. bovis.
Asunto(s)
Anaplasma/aislamiento & purificación , Anaplasmosis/epidemiología , Reservorios de Enfermedades , Ehrlichia/aislamiento & purificación , Ehrlichiosis/veterinaria , Musarañas/microbiología , Anaplasma/genética , Anaplasmosis/microbiología , Animales , Secuencia de Bases , Bovinos , ADN Bacteriano/sangre , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/sangre , ADN Ribosómico/química , ADN Ribosómico/genética , Ehrlichia/genética , Ehrlichiosis/epidemiología , Ehrlichiosis/microbiología , Femenino , Variación Genética , Masculino , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , ARN Ribosómico 18S/genética , Análisis de Secuencia de ADN/veterinaria , Sudáfrica/epidemiologíaRESUMEN
Using the foraging movements of an insectivorous bat, Myotis mystacinus, we describe temporal switching of foraging behaviour in response to resource availability. These observations conform to predictions of optimized search under the Lévy flight paradigm. However, we suggest that this occurs as a result of a preference behaviour and knowledge of resource distribution. Preferential behaviour and knowledge of a familiar area generate distinct movement patterns as resource availability changes on short temporal scales. The behavioural response of predators to changes in prey fields can elicit different functional responses, which are considered to be central in the development of stable predatorprey communities. Recognizing how the foraging movements of an animal relate to environmental conditions also elucidates the evolution of optimized search and the prevalence of discrete strategies in natural systems. Applying techniques that use changes in the frequency distribution of movements facilitates exploration of the processes that underpin behavioural changes.
Asunto(s)
Quirópteros/fisiología , Conducta Alimentaria/fisiología , Vuelo Animal/fisiología , AnimalesRESUMEN
Aggregation of parasites amongst hosts is important for the epidemiology of vector-borne diseases because hosts that support the majority of the vector population are responsible for the majority of pathogen transmission. Ixodes ricinus ticks transmit numerous pathogens of medical importance including Borrelia burgdorferi s.l. and tick-borne encephalitis virus. One transmission route involved is 'co-feeding transmission', where larvae become infected via feeding alongside infected nymphs. The aggregation of ticks on hosts leads to an increase in the number of larvae feeding alongside nymphs, increasing the transmission potential via this route. The basic reproduction number, R 0, can be used to identify whether a pathogen will become established if introduced. In the current study we use previously published tick, and pathogen, specific data to parameterize an R 0 model to investigate how the degree of aggregation of ticks on hosts affects pathogen persistence. The coincident aggregated distribution permitted the establishment of tick-borne encephalitis virus but did not influence whether B. burgdorferi s.l. became established. The relationship between the k-exponent of the negative binomial distribution and R 0 was also defined. Therefore, the degree of aggregation of ticks on small mammal hosts has important implications for the risk to human health in a given area.
Asunto(s)
Vectores Arácnidos , Encefalitis Transmitida por Garrapatas/transmisión , Interacciones Huésped-Parásitos , Ixodes/microbiología , Ixodes/virología , Enfermedad de Lyme/transmisión , Infestaciones por Garrapatas/epidemiología , Animales , Vectores Arácnidos/microbiología , Vectores Arácnidos/virología , Borrelia burgdorferi , Reservorios de Enfermedades , Virus de la Encefalitis Transmitidos por Garrapatas , Mamíferos , Infestaciones por Garrapatas/microbiología , Infestaciones por Garrapatas/virologíaAsunto(s)
Anaplasma phagocytophilum , Ehrlichiosis/veterinaria , Enfermedades de las Cabras/epidemiología , Animales , Animales Salvajes/microbiología , Animales Salvajes/parasitología , Ehrlichiosis/epidemiología , Ehrlichiosis/transmisión , Femenino , Enfermedades de las Cabras/transmisión , Cabras , Masculino , Irlanda del Norte/epidemiología , Especificidad de la EspecieRESUMEN
Bartonella are hemoparasites exploiting a range of mammals as reservoir hosts. Several species are zoonotic pathogens. Fleas, lice, and other arthropods, such as ticks, have been implicated as vectors. While the competence of ticks as vectors of Bartonella species has recently been demonstrated, the epidemiological significance of ticks as vectors of Bartonella species in wildlife populations remains unknown. We used the presence of deer at study sites to control the presence of Ixodes ricinus ticks, and used this system to determine whether I. ricinus contributes to the epidemiology of Bartonella species infections in small mammals. Ticks were present at all sites with deer, but were absent from all sites without deer; however, the abundance of ticks on small mammals did not affect the probability of wood mice being infected with Bartonella species. Data presented here indicate that I. ricinus is not involved in the transmission of Bartonella in woodland rodents.
Asunto(s)
Vectores Artrópodos/microbiología , Infecciones por Bartonella/veterinaria , Bartonella/fisiología , Ixodes/microbiología , Murinae/parasitología , Animales , Bartonella/clasificación , Bartonella/genética , Infecciones por Bartonella/microbiología , Infecciones por Bartonella/transmisión , Ciervos , Demografía , Ecosistema , Femenino , Variación Genética , Masculino , Ratones , Modelos Biológicos , Irlanda del Norte , Factores de RiesgoRESUMEN
Ticks are important vectors of numerous pathogens causing illness, fatalities, and economic loss worldwide. Infectious disease episodes are increasing, and novel tick-borne pathogens are described frequently. Identification of novel reservoir hosts and vectors of tick-borne pathogens is essential if control measures are to be successful. In South Africa, the eastern rock sengi, Elephantulus myurus , hosts a number of tick species of veterinary importance. Despite this, there remains a paucity of information regarding the tick fauna of this species, the pathogen associations of ticks that it hosts, and its role as a reservoir host of tick-borne pathogens. The current study documents the tick fauna of E. myurus and sympatric small mammal species in Limpopo Province, South Africa. The pathogen associations of ticks hosted by elephant shrews were also investigated by PCR screening of engorged nymphs for a broad range of bacterial and protozoan tick-borne infections, including Borrelia burgdorferi sensu lato and members of Apicomplexa and the order Rickettsiales. There were marked differences in tick species and abundance among host species. Elephantulus myurus was heavily, and predominantly, parasitized by an as-yet undescribed tick species that we identify as Rhipicephalus sp. near warburtoni. PCR and sequence analysis revealed the presence of Anaplasma bovis in this tick species, which may have consequences for livestock production and conservation efforts in the area where this tick species occurs.
Asunto(s)
Anaplasma/aislamiento & purificación , Anaplasmosis/transmisión , Vectores Arácnidos/microbiología , Rhipicephalus/microbiología , Musarañas/parasitología , Infestaciones por Garrapatas/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/microbiología , Enfermedades de los Bovinos/transmisión , Reservorios de Enfermedades , Femenino , Modelos Lineales , Masculino , Infestaciones por Garrapatas/parasitologíaRESUMEN
DNA methylation is a biochemical process where a DNA base, usually cytosine, is enzymatically methylated at the 5-carbon position. An epigenetic modification associated with gene regulation, DNA methylation is of paramount importance to biological health and disease. Recently, the quest to unravel the Human Epigenome commenced, calling for a modernization of previous DNA methylation profiling techniques. Here, we describe the major developments in the methodologies used over the past three decades to examine the elusive epigenome (or methylome). The earliest techniques were based on the separation of methylated and unmethylated cytosines via chromatography. The following years would see molecular techniques being employed to indirectly examine DNA methylation levels at both a genome-wide and locus-specific context, notably immunoprecipitation via anti-5'methylcytosine and selective digestion with methylation-sensitive restriction endonucleases. With the advent of sodium bisulfite treatment of DNA, a deamination reaction that converts cytosine to uracil only when unmethylated, the epigenetic modification can now be identified in the same manner as a DNA base-pair change. More recently, these three techniques have been applied to more technically advanced systems such as DNA microarrays and next-generation sequencing platforms, bringing us closer to unveiling a complete human epigenetic profile.
RESUMEN
BACKGROUND: Reproductive proteins are central to the continuation of all mammalian species. The evolution of these proteins has been greatly influenced by environmental pressures induced by pathogens, rival sperm, sexual selection and sexual conflict. Positive selection has been demonstrated in many of these proteins with particular focus on primate lineages. However, the mammalia are a diverse group in terms of mating habits, population sizes and germ line generation times. We have examined the selective pressures at work on a number of novel reproductive proteins across a wide variety of mammalia. RESULTS: We show that selective pressures on reproductive proteins are highly varied. Of the 10 genes analyzed in detail, all contain signatures of positive selection either across specific sites or in specific lineages or a combination of both. Our analysis of SP56 and Col1a1 are entirely novel and the results show positively selected sites present in each gene. Our findings for the Col1a1 gene are suggestive of a link between positive selection and severe disease type. We find evidence in our dataset to suggest that interacting proteins are evolving in symphony: most likely to maintain interacting functionality. CONCLUSION: Our in silico analyses show positively selected sites are occurring near catalytically important regions suggesting selective pressure to maximize efficient fertilization. In those cases where a mechanism of protein function is not fully understood, the sites presented here represent ideal candidates for mutational study. This work has highlighted the widespread rate heterogeneity in mutational rates across the mammalia and specifically has shown that the evolution of reproductive proteins is highly varied depending on the species and interacting partners. We have shown that positive selection and disease are closely linked in the Col1a1 gene.
Asunto(s)
Mamíferos/genética , Proteínas/genética , Animales , Colágeno Tipo I/química , Colágeno Tipo I/genética , Fertilización , Humanos , Mamíferos/fisiología , Filogenia , Reproducción , Selección GenéticaRESUMEN
AIM: The aim of this clinicostatistical study was to profile the complete denture wearers of two different populations, to determine any possible relationship between the prevalence of temporomandibular disorders (TMDs) and factors involved in complete denture wearing and to compare this prevalence between the groups. MATERIALS AND METHODS: Denture wearers who attended the clinics of the Dental School and Hospital, University of Bristol, U.K. (group A) and the Dental School, University of Athens, Greece (group B), were examined. An approximately equal number of patients; 115 for group A and 136 for group B, were selected. The examination included: (a) a history record with reference to sex, age, years of complete denture experience, sets of dentures used, age of the current dentures, time period of every day denture wearing, any difficulties on opening the mouth, and/or pain at the temporomandibular joint (TMJ) region and (b) a craniomandibular clinical examination in relation to midline deviation, pain and sounds from the joints, pain in the related muscles and inspection of the vertical dimension of occlusion. Data collected were analyzed using the chi-square test. RESULTS: Denture wearers of group A were older, presented with greater experience in complete denture wearing, used more sets of dentures, most wore dentures exhibiting decreased vertical dimension of occlusion and wore their dentures only in the day time. The TMDs prevalence was not statistically significantly different between A and B groups (34.8% and 41.2% respectively). In group B the TMDs prevalence was greater in females. There was a decreasing TMDs prevalence with increasing age. Neither of the groups showed significant TMDs prevalence in relation to the denture experience, the number of dentures used, the age of the present denture nor the vertical dimension of occlusion. Group B showed a decreasing TMDs prevalence in relation to continuous denture wearing. CONCLUSIONS: This clinicostatistical study showed that two different population groups of complete denture wearers who presented with different profiles have similar prevalence of TMDs.