RESUMEN
A total of 150 rhizobacteria and endorhizobacteria previously isolated from three different horticultural crops; strawberry, apple and apricot were screened for antagonistic activitiy against Clavibacter michiganensis ssp. michiganensis. Among them strain S1, exhibiting significantly higher antagonistic and plant growth promoting ability was characterized as Bacillus amyloliquefaciens based on morphological, biochemical and partial gene sequence analysis of 16S rRNA. B. amyloliquefaciens strain S1 showed maximum growth inhibition of C. michiganensis (12â¯mm). Moreover, B. amyloliquefaciens strain S1 exhibit significant phosphorus solubilization (94.16 %SEl) and indole acetic acid (27⯵gâ¯ml-1) production under in vitro conditions. Antagonistic activity of Bacillus amyloliquefaciens strain S1 was compared with other four strains KU2S1, R2S(1), RG1(3) and AG1(7) against bacterial canker of tomato under net house conditions. Minimum bacterial canker disease incidence (30.0%) was recorded in B. amyloliquefaciens S1 followed by RG1(3) after 30 days of inoculation. The bio-control efficacy was higher in B. amyloliquefaciens S1 treated plants, followed by RG1(3).
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Actinobacteria/crecimiento & desarrollo , Antibiosis , Bacillus amyloliquefaciens/crecimiento & desarrollo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Solanum lycopersicum/microbiología , Bacillus amyloliquefaciens/clasificación , Bacillus amyloliquefaciens/genética , Bacillus amyloliquefaciens/aislamiento & purificación , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácidos Indolacéticos/metabolismo , Fósforo/metabolismo , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Fructose consumption is responsible for the onset of insulin resistance (IR), and metabolic syndrome. It possesses no functional utility in body and its detrimental effects on hepatic metabolic milieu are beyond those produced by glucose. The need of the hour is to identify fructose-induced IR as an unique pathological state to be managed differentially. The effect of aqueous leaf extract of Aegle marmelos (AM) on hepatic markers of insulin resistance using HepG2 cells cultured in either fructose or glucose-rich environment is investigated. Human hepatocellular carcinoma cells (HepG2) were grown under standard conditions in either-DMEM without glucose (NC), DMEM with high glucose 25 mM (Glu), DMEM-glucose+0.55 mM fructose (FC1), DMEM-glucose+1 mM fructose (FC2) or DMEM-glucose+1 mM fructose+0.1 µM insulin (FC3). The cells were treated with either AM, rutin, quercetin, metformin or pioglitazone and assessed for levels of hexokinase, phosphofructokinase (PFK), aldehyde dehydrogenase, phosphatidylinositol kinase (PI3K), signal transducer and activator of transcription-3 (STAT-3), mitochondrial target of rapamycin (mTOR), hypoxia-induced factor (HIF-1α), vascular endothelial growth factor (VEGF) and tumour necrosis factor (TNF-α). Summarily, when results from fructose- and glucose-rich environment were compared, then (1) IR was more pronounced in former; (2) AM performed better in former; (3) metformin and pioglitazone were equivocal in either; (4) rutin and quercetin showed deviant effects from AM; and lastly (5) effects of rutin were closer to AM than quercetin. We hypothesize that AM ameliorates fructose-induced IR through a mechanism which is distinct from standard drugs and not shared by individual phytoconstituents in toto.
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Aegle/química , Fructosa/farmacología , Glucosa/farmacología , Glucólisis/efectos de los fármacos , Insulina/metabolismo , Extractos Vegetales/farmacología , Transducción de Señal/efectos de los fármacos , Células Hep G2 , Humanos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/patología , Extractos Vegetales/químicaRESUMEN
Changes in seroprevalence of cysticercosis diagnosed in Chandigarh, India between 1998 and 2014 were investigated by extraction and analysis of data from records held at the Postgraduate Institute of Medical Education and Research in Chandigarh. Among the total number of samples for which cysticercosis had been suspected during this period (N = 9650), 1716 (17·8%) were seropositive. Adults were more likely to be seropositive than children, and women were more likely to be seropositive than men. In addition to there being fewer patients with suspicion of cysticercosis over the data analysis period, the proportion of patients seropositive also reduced significantly. Despite these reductions, which are probably associated with improved infrastructure and sanitation within Chandigarh, and despite meat consumption being relatively rare in this area, the extent of cysticercosis in this population remains problematic. Further efforts should be made to reduce transmission of this infection, with particular emphasis on women. Such efforts should follow the One Health concept, and involve medical efforts (including diagnosis and treatment of T. solium tapeworm carriers), veterinary efforts directed towards meat inspection and prevention of infection of pigs, and environmental health and sanitation engineers (to minimize environmental contamination with human waste).
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Cisticercosis/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Niño , Preescolar , Cisticercosis/prevención & control , Cisticercosis/transmisión , Transmisión de Enfermedad Infecciosa/prevención & control , Conducta Alimentaria , Femenino , Salud Global , Humanos , India/epidemiología , Lactante , Masculino , Persona de Mediana Edad , Estudios Seroepidemiológicos , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/prevención & control , Adulto Joven , Zoonosis/epidemiología , Zoonosis/prevención & controlRESUMEN
Haemosporidian blood parasites are transmitted to a wide range of avian hosts via blood-sucking dipteran vectors. Microscopy has revealed an impressive diversity of avian haemosporidia with more than 250 species described. Moreover, PCR and subsequent sequence analyses have suggested a much greater diversity of haemosporidia than morphological analyses alone. Given the importance of these parasites, very few studies have focused on the charismatic hummingbirds. To date, three Haemoproteus species (Haemoproteus archilochus, Haemoproteus trochili, and Haemoproteus witti) and one Leucocytozoon species (Leucocytozoon quynzae) have been described in blood samples taken from hummingbirds (Trochilidae). Unconfirmed Plasmodium lineages have also been detected in hummingbirds. Here, we report the detection of H. archilochus in two hummingbird species (Calypte anna and Archilochus alexandri) sampled in Northern California and perform a phylogenetic analysis of mitochondrial cytochrome b (cyt b) gene lineages. A total of 261 hummingbirds (157 C. anna, 104 A. alexandri) were sampled and screened for blood parasites using PCR and microscopy techniques. Combining both methods, 4 (2.55%) haemosporidian infections were detected in C. anna and 18 (17.31%) haemosporidian infections were detected in A. alexandri. Molecular analyses revealed four distinct H. archilocus cyt b lineages, which clustered as a monophyletic clade. No species of Plasmodium or Leucocytozoon were detected in this study, raising the possibility of specific vector associations with hummingbirds. These results provide resources for future studies of haemosporidian prevalence, diversity, and pathogenicity in California hummingbird populations.
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Enfermedades de las Aves/parasitología , Haemosporida/aislamiento & purificación , Infecciones Protozoarias en Animales/parasitología , Animales , Enfermedades de las Aves/epidemiología , Aves , California/epidemiología , Citocromos b/genética , Haemosporida/clasificación , Haemosporida/genética , Parasitemia , Filogenia , Prevalencia , Infecciones Protozoarias en Animales/epidemiología , Análisis de Secuencia de ADN/veterinariaRESUMEN
Pregnancy is accompanied by several haemodynamic, biochemical and haematological changes, which may lead to severe problems, if they are not suitably addressed. The current study highlights the haematological and biochemical differences observed in anaemic (AP) and non-anaemic primigravida (NAP), in the 2nd trimester, in a north Indian population. There were significant differences (p < 0.05) in the body weight and body temperature of NAP compared with AP. A significant decrease (p < 0.001) in haematological parameters including haemoglobin, haematocrit, erythrocyte count, MCH and MCHC, was observed in AP; however, MCV was found to be significantly higher (p = 0.038). Many biochemical parameters viz. potassium, albumin, total protein and calcium levels were significantly reduced (p < 0.01) in AP, except alkaline phosphatase whose level was found significantly increased (p < 0.01). The findings of the study suggest that haematological and biochemical changes take place in anaemia during pregnancy. Further, the results obtained should be used for establishing normative values for similar populations.
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Anemia/sangre , Número de Embarazos , Complicaciones Hematológicas del Embarazo/sangre , Femenino , Humanos , India , Embarazo , Segundo Trimestre del Embarazo/sangre , Valores de Referencia , Adulto JovenRESUMEN
Although brucellosis is a common zoonotic disease worldwide, infection with Brucella canis is rare and often difficult to diagnose. We describe the clinical and epidemiological aspects of a case of B. canis peritonitis.
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Brucella canis/aislamiento & purificación , Brucelosis/diagnóstico , Brucelosis/patología , Peritonitis/diagnóstico , Peritonitis/etiología , Líquido Ascítico/microbiología , Brucelosis/microbiología , Humanos , Masculino , Persona de Mediana Edad , Peritonitis/microbiologíaRESUMEN
Recent developments in colonic surgery generate exciting opportunities for surgeons and trainees. In the first instance, the anatomy of the entire mesenteric organ has been clarified and greatly simplified. No longer is it regarded as fragmented and complex. Rather it is continuous from duodenojejunal flexure to mesorectum, spanning the gastrointestinal tract between. Recent histologic findings have demonstrated that although apposed to the retroperitoneum, the mesenteric organ is separated from this via Toldt's fascia. These fundamentally important observations underpin the principles of complete mesocolic excision, where the mesocolic package is maintained intact, following extensive mesenterectomy. More importantly, they provide the first opportunity to apply a canonical approach to the development of nomenclature in resectional colonic surgery. In this review, we demonstrate how the resultant nomenclature is entirely anatomic based, and for illustrative purposes, we apply it to the procedure conventionally referred to as right hemicolectomy, or ileocolic resection.
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Colectomía/métodos , Colon/anatomía & histología , Colon/cirugía , Mesocolon/anatomía & histología , Mesocolon/cirugía , Terminología como Asunto , HumanosAsunto(s)
Resistencia a Medicamentos , Glucocorticoides/farmacología , Inmunosupresores/farmacología , Arteritis de Takayasu/tratamiento farmacológico , Ustekinumab/administración & dosificación , Adulto , Fármacos Dermatológicos/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Arteritis de Takayasu/diagnóstico , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
BACKGROUND: Preterm birth or low birth weight is the single largest cause of death in newborns, however this mortality can be reduced through newborn care interventions, including Kangaroo Mother Care (KMC). Previously, a multi-country randomized controlled trial, coordinated by the World Health Organization (WHO), reported a significant survival advantage with initiation of continuous KMC immediately after birth compared with initiation of continuous KMC a few days after birth when the baby is considered clinically stable. Whether the survival advantage would lead to higher rates of neurodevelopmental morbidities, or the immediate KMC will also have a beneficial effect on cognitive development also, has not been investigated. We therefore propose to test the hypothesis that low-birth-weight infants exposed to immediate KMC will have lower rates of neurodevelopmental impairment in comparison to traditional KMC-treated infants, by prospectively following up infants already enrolled in the immediate KMC trial for the first 2 years of life, and assessing their growth and neurodevelopment. METHODS: This prospective cohort study will enroll surviving neonates from the main WHO immediate KMC trial. The main trial as well as this follow-up study are being conducted in five low- and middle-income countries in South Asia and sub-Saharan Africa. The estimated sample size for comparison of the risk of neurodevelopmental impairment is a total of 2200 children. The primary outcome will include rates of cerebral palsy, hearing impairment, vision impairment, mental and motor development, and epilepsy and will be assessed by the age of 3 years. The analysis will be by intention to treat. DISCUSSION: Immediate KMC can potentially reduce low-birth-weight-associated complications such as respiratory disease, hypothermia, hypoglycemia, and infection that can result in impaired neurocognitive development. Neuroprotection may also be mediated by improved physiological stabilization that may lead to better maturation of neural pathways, reduced risk of hypoxia, positive parental impact, improved sleep cycles, and improved stress responses. The present study will help in evaluating the overall impact of KMC by investigating the long-term effect on neurodevelopmental impairment in the survivors. TRIAL REGISTRATION: Clinical Trials Registry-India CTRI/2019/11/021899. Registered on 06 November 2019. Trials registration of parent trial: ACTRN12618001880235; Clinical Trials Registry-India: CTRI/2018/08/015369.
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Método Madre-Canguro , Nacimiento Prematuro , Recién Nacido , Humanos , Femenino , Niño , Método Madre-Canguro/métodos , Peso al Nacer , Estudios de Seguimiento , Estudios Prospectivos , Mortalidad Infantil , Aumento de Peso , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Single port laparoscopy is a relatively new niche in the expanding spectrum of minimal access surgery for colorectal disease. To date the published experience has predominantly focused on planned operations for neoplasia in the elective setting. It seems probable however that the benefits of minimal abdominal wounding will be greatest among those patients with the highest risk of impaired wound healing. Combining this with the impression of improved cosmesis suggests that (the mostly young) patients with inflammatory bowel disease needing urgent operation are the most likely to appreciate and benefit from the extraoperative effort. The extension of single port surgery to the acute setting and for debilitated individuals is therefore a likely next step advance in broadening the category of patients for whom it represents a real benefit and ultimately aid in focusing by selection the subgroups for whom this technique is best suited and most appropriate. We describe here our approach (including routine use of a surgical glove port) to patients presenting for urgent colorectal operation for benign disease. As provision of specialized approaches regardless of timing or mode of presentation is a defining component of any specialty service, this concept will soon be more fully elucidated and established.
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Colectomía/instrumentación , Colectomía/métodos , Servicio de Urgencia en Hospital , Laparoscópía Mano-Asistida , Enfermedades Inflamatorias del Intestino/cirugía , Adulto , Anciano , Enfermedad de Crohn/cirugía , Estudios de Factibilidad , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
Most of the cases of intussusception in children are labeled as idiopathic and not usually investigated. Only rare cases of chronic or recurrent intussusception receive greater attention and further investigations. Celiac disease appears to be associated with modestly increased risk of intussusception, although most of these cases remain asymptomatic. Debate still continues as to whether all patients of intussusception should be screened for celiac disease. We present case of a 7 years old child who presented with recurrent intussusception, underwent laparotomy initially and was later diagnosed to have celiac disease.
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Enfermedad Celíaca , Intususcepción , Enfermedad Celíaca/complicaciones , Enfermedad Celíaca/diagnóstico , Niño , Humanos , Intususcepción/diagnóstico , Intususcepción/etiología , Intususcepción/cirugía , Laparotomía/efectos adversosRESUMEN
Purpose: The association between exposure to Toxocara canis and epilepsy is at the best contentious. Most of previous studies were retrospective, community-based, and contradictory to one another. As the impact of a positive association on the magnitude of epilepsy will be huge especially in developing countries where toxocariasis is common owing to poor hygienic practices, this study was carried out to determine whether exposure to T. canis predisposes to development of epilepsy. Patients and Methods: This case-controlled observational study was carried out a tertiary healthcare center in North India on 120 patients with newly diagnosed epilepsy who presented within 3 months of diagnosis. A total of 120 age- and sex-matched individuals from the same community were chosen as controls. Epilepsy was defined according to ILAE 1993 definition. Serological testing for T. canis was carried out using commercially available ELISA kits. All the positive samples were subjected to Western blot testing for confirmation. Results: The prevalence of antibodies to T. canis was similar in cases (16/120; 13.3%) and controls (16/120; 13.3%). Among the various risk factors, history of pica was significantly associated with T. canis seropositivity, while lack of hand washing was significantly associated with higher risk of epilepsy. Conclusion: Our study could not find any association between exposure to T. canis and epilepsy.
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Epilepsia , Toxocara canis , Toxocariasis , Animales , Humanos , Estudios Retrospectivos , Epilepsia/diagnóstico , Toxocariasis/complicaciones , Toxocariasis/epidemiología , Inmunoglobulina G , Ensayo de Inmunoadsorción EnzimáticaRESUMEN
The border zone (BZ) of the infarcted heart is a geographically complex and biologically enigmatic interface separating poorly perfused infarct zones (IZs) from remote zones (RZs). The cellular and molecular mechanisms of myocardial BZs are not well understood because microdissection inevitably combines them with uncontrolled amounts of RZs and IZs. Here, we use single-cell/nucleus RNA sequencing, spatial transcriptomics and multiplexed RNA fluorescence in situ hybridization to redefine the BZ based on cardiomyocyte transcriptomes. BZ1 (Nppa + Xirp2 -) forms a hundreds-of-micrometer-thick layer of morphologically intact cells adjacent to RZs that are detectable within an hour of injury. Meanwhile, BZ2 (Nppa + Xirp2 +) forms a near-single-cell-thick layer of morphologically distorted cardiomyocytes at the IZ edge that colocalize with matricellular protein-expressing myofibroblasts and express predominantly mechanotransduction genes. Surprisingly, mechanical injury alone is sufficient to induce BZ genes. We propose a 'loss of neighbor' hypothesis to explain how ischemic cell death mechanically destabilizes the BZ to induce its transcriptional response.
RESUMEN
Critical to the mitigation of parasitic vector-borne diseases is the development of accurate spatial predictions that integrate environmental conditions conducive to pathogen proliferation. Species of Plasmodium and Trypanosoma readily infect humans, and are also common in birds. Here, we develop predictive spatial models for the prevalence of these blood parasites in the olive sunbird (Cyanomitra olivacea). Since this species exhibits high natural parasite prevalence and occupies diverse habitats in tropical Africa, it represents a distinctive ecological model system for studying vector-borne pathogens. We used PCR and microscopy to screen for haematozoa from 28 sites in Central and West Africa. Species distribution models were constructed to associate ground-based and remotely sensed environmental variables with parasite presence. We then used machine-learning algorithm models to identify relationships between parasite prevalence and environmental predictors. Finally, predictive maps were generated by projecting model outputs to geographically unsampled areas. Results indicate that for Plasmodium spp., the maximum temperature of the warmest month was most important in predicting prevalence. For Trypanosoma spp., seasonal canopy moisture variability was the most important predictor. The models presented here visualize gradients of disease prevalence, identify pathogen hotspots and will be instrumental in studying the effects of ecological change on these and other pathogens.
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Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/parasitología , Passeriformes/parasitología , Infecciones Protozoarias en Animales/sangre , África Central/epidemiología , África Occidental/epidemiología , Animales , Enfermedades de las Aves/sangre , Ambiente , Malaria Aviar/sangre , Malaria Aviar/epidemiología , Modelos Biológicos , Plasmodium/aislamiento & purificación , Prevalencia , Infecciones Protozoarias en Animales/epidemiología , Especificidad de la Especie , Trypanosoma/aislamiento & purificación , Tripanosomiasis/sangre , Tripanosomiasis/epidemiología , Tiempo (Meteorología)RESUMEN
Malaria parasites use vertebrate hosts for asexual multiplication and Culicidae mosquitoes for sexual and asexual development, yet the literature on avian malaria remains biased towards examining the asexual stages of the life cycle in birds. To fully understand parasite evolution and mechanism of malaria transmission, knowledge of all three components of the vector-host-parasite system is essential. Little is known about avian parasite-vector associations in African rainforests where numerous species of birds are infected with avian haemosporidians of the genera Plasmodium and Haemoproteus. Here we applied high resolution melt qPCR-based techniques and nested PCR to examine the occurrence and diversity of mitochondrial cytochrome b gene sequences of haemosporidian parasites in wild-caught mosquitoes sampled across 12 sites in Cameroon. In all, 3134 mosquitoes representing 27 species were screened. Mosquitoes belonging to four genera (Aedes, Coquillettidia, Culex and Mansonia) were infected with twenty-two parasite lineages (18 Plasmodium spp. and 4 Haemoproteus spp.). Presence of Plasmodium sporozoites in salivary glands of Coquillettidia aurites further established these mosquitoes as likely vectors. Occurrence of parasite lineages differed significantly among genera, as well as their probability of being infected with malaria across species and sites. Approximately one-third of these lineages were previously detected in other avian host species from the region, indicating that vertebrate host sharing is a common feature and that avian Plasmodium spp. vector breadth does not always accompany vertebrate-host breadth. This study suggests extensive invertebrate host shifts in mosquito-parasite interactions and that avian Plasmodium species are most likely not tightly coevolved with vector species.
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Culicidae/parasitología , Especificidad del Huésped , Malaria Aviar/parasitología , Plasmodium/genética , Animales , Camerún , ADN Protozoario/genética , Vectores de Enfermedades , Femenino , Filogenia , Glándulas Salivales/parasitología , Análisis de Secuencia de ADN , Especificidad de la EspecieRESUMEN
AIM: To test the antimicrobial efficacy and flow properties of Guttaflow, Epiphany sealer and AH-Plus sealer. METHODOLOGY: With the use of Enterococcus faecalis ATCC 29212 as a test organism, both the agar diffusion test (ADT) and direct contact test (DCT) were performed. For DCT, sealers were mixed and placed over the bottom of sterile screw-capped test tubes. A 50 µL bacterial suspension was placed on the tested material samples. Bacteria were allowed to directly come in contact with the sealers for 1 h at 37 °C in one group and for 24 h in the other group. The suspensions were then diluted and inoculated over blood agar plates, and bacterial colony counts were determined with the use of a digital colony counter. The data in both 1- and 24-h groups were individually analysed using repeated measures ANOVA. Kruskal Wallis tests were further used to obtain comparison between 1- and 24-h results for all three sealers. In the flow assay, the sealers were placed between two glass slides, and a weight of 500 g was placed on the top of the glass. The diameters of the formed discs were recorded. RESULTS: For both the ADT and DCT tests, Epiphany and AH-Plus sealer reduced the bacterial counts significantly (P = 0.000). Epiphany produced a greater reduction in bacterial counts when compared to AH-Plus in both the tests (P = 0.000). Guttaflow paste failed to show any antibacterial activity in both ADT & DCT. According to the flow test, all root canal sealers flowed; Epiphany sealer had the maximum flow under the given conditions, followed by AH-Plus sealer and Guttaflow paste. CONCLUSIONS: Antimicrobial activity of the sealers was greatest for Epiphany followed by AH-Plus sealer and Guttaflow. Epiphany sealer had the maximum flow followed by AH-Plus sealer and Guttaflow.
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Antiinfecciosos Locales/farmacología , Enterococcus faecalis/efectos de los fármacos , Materiales de Obturación del Conducto Radicular/farmacología , Recuento de Colonia Microbiana , Filtración Dental/prevención & control , Dimetilpolisiloxanos/farmacología , Combinación de Medicamentos , Resinas Epoxi/farmacología , Gutapercha/farmacología , Ensayo de Materiales , Pruebas de Sensibilidad Microbiana , Reología , ViscosidadRESUMEN
Hummingbirds are vital members of terrestrial ecosystems, and because of their high metabolic requirements, they serve as indicators of ecosystem health. Monitoring the parasitic infections of hummingbirds is thus especially important. Haemosporidians, a widespread group of avian blood parasites, are known to infect hummingbirds, but little is known about the prevalence and diversity of these parasites in hummingbirds. The prevalence of haemosporidians in several hummingbird species was examined and we compared 4 different tissue types in detecting parasites by polymerase chain reaction (PCR). Blood samples from 339 individuals of 3 different hummingbird species were tested, and 4 individuals were found positive for haemosporidian infection, a prevalence of 1.2%. Hummingbird carcasses (n = 70) from 5 different hummingbird species were also sampled to assess differences in detection success of haemosporidians in heart, kidney, liver, and pectoral muscle tissue samples. Detection success was similar among tissue types, with haemosporidian prevalence of 9.96% in heart tissue, 9.52% in kidney tissue, 10.76% in liver tissue, and 11.76% in pectoral muscle tissue. All tissue samples positive for haemosporidian infection were from the Black-chinned Hummingbird (Archilochus alexandri). Possible reasons for low prevalence of these blood parasites could include low susceptibility to insect vectors or parasite incompatibility in these hummingbirds.
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Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/parasitología , Haemosporida/aislamiento & purificación , Infecciones Protozoarias en Animales/epidemiología , Animales , Arizona/epidemiología , Enfermedades de las Aves/sangre , Aves , California/epidemiología , Femenino , Masculino , Prevalencia , Infecciones Protozoarias en Animales/sangre , Infecciones Protozoarias en Animales/parasitologíaRESUMEN
In this time of unprecedented global change, infectious diseases will impact humans and wildlife in novel and unknown ways. Climate change, the introduction of invasive species, urbanization, agricultural practices and the loss of biodiversity have all been implicated in increasing the spread of infectious pathogens. In many regards, deforestation supersedes these other global events in terms of its immediate potential global effects in both tropical and temperate regions. The effects of deforestation on the spread of pathogens in birds are largely unknown. Birds harbor many of the same types of pathogens as humans and in addition can spread infectious agents to humans and other wildlife. It is thought that avifauna have gone extinct due to infectious diseases and many are presently threatened, especially endemic island birds. It is clear that habitat degradation can pose a direct threat to many bird species but it is uncertain how these alterations will affect disease transmission and susceptibility to disease. The migration and dispersal of birds can also change with habitat degradation, and thus expose populations to novel pathogens. Some recent work has shown that the results of landscape transformation can have confounding effects on avian malaria, other haemosporidian parasites and viruses. Now with advances in many technologies, including mathematical and computer modeling, genomics and satellite tracking, scientists have tools to further research the disease ecology of deforestation. This research will be imperative to help predict and prevent outbreaks that could affect avifauna, humans and other wildlife worldwide.
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Enfermedades de las Aves/epidemiología , Aves , Enfermedades Transmisibles/epidemiología , Conservación de los Recursos Naturales , Animales , Enfermedades de las Aves/transmisión , Cambio Climático , Enfermedades Transmisibles/transmisión , Brotes de Enfermedades , Humanos , Modelos Teóricos , Zoonosis/epidemiologíaRESUMEN
A new cadherin-like protein (CLP) was identified in oocytes, eggs, and cleavage stage embryos of Xenopus laevis. As a probe for detecting new cadherin proteins, an antiserum was raised to a 17 amino acid peptide derived from a highly conserved region in the cytoplasmic domain of all cadherins which have been sequenced to date. This antipeptide antibody recognized Xenopus E-cadherin and a polypeptide in Xenopus brain extracts similar to N-cadherin, which were independently identified by specific mAbs. In extracts of eggs and midblastula stage embryos the antipeptide antibody recognized specifically a 120-kD glycoprotein that migrated faster on SDS gels than the 140-kD E- and N-cadherin polypeptides. This 120-kD polypeptide was not recognized by the mAbs specific to E- and N-cadherin. In fact, E- and N-cadherin were not detectable in eggs or midblastula stage embryos. The possible relationship of CLP to P-cadherin, which has been identified in mouse tissues, has not yet been determined. CLP was synthesized by large, late stage oocytes. When oocytes were induced to mature in vitro with progesterone it accumulated to the same level found in normally laid eggs. It did not accumulate further to any significant extent during the early cleavage stages. CLP was detected on the surface of stage 8 blastomeres by cell surface biotinylation, but only after the tight junctions of the blastula epithelium were opened by removal of Ca2+. We conclude that CLP is a maternally encoded protein that is the major, if not only, cadherin-related protein present in the earliest stages of Xenopus development, and we propose that it may play a role in the Ca2(+)-dependent adhesion and junction formation between cleavage stage blastomeres.