Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 67
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
BMC Pulm Med ; 23(1): 326, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667267

RESUMO

BACKGROUND: Ex vivo lung perfusion (EVLP) constitutes a tool with great research potential due to its advantages over in vivo and in vitro models. Despite its important contribution to lung reconditioning, this technique has the disadvantage of incurring high costs and can induce pulmonary endothelial injury through perfusion and ventilation. The pulmonary endothelium is made up of endothelial glycocalyx (EG), a coating of proteoglycans (PG) on the luminal surface. PGs are glycoproteins linked to terminal sialic acids (Sia) that can affect homeostasis with responses leading to edema formation. This study evaluated the effect of two ex vivo perfusion solutions on lung function and endothelial injury. METHODS: We divided ten landrace swine into two groups and subjected them to EVLP for 120 min: Group I (n = 5) was perfused with Steen® solution, and Group II (n = 5) was perfused with low-potassium dextran-albumin solution. Ventilatory mechanics, histology, gravimetry, and sialic acid concentrations were evaluated. RESULTS: Both groups showed changes in pulmonary vascular resistance and ventilatory mechanics (p < 0.05, Student's t-test). In addition, the lung injury severity score was better in Group I than in Group II (p < 0.05, Mann-Whitney U); and both groups exhibited a significant increase in Sia concentrations in the perfusate (p < 0.05 t-Student) and Sia immunohistochemical expression. CONCLUSIONS: Sia, as a product of EG disruption during EVLP, was found in all samples obtained in the system; however, the changes in its concentration showed no apparent correlation with lung function.


Assuntos
Lesão Pulmonar , Ácido N-Acetilneuramínico , Animais , Suínos , Respiração , Perfusão , Pulmão , Modelos Teóricos
2.
Mem Inst Oswaldo Cruz ; 116: e210275, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35019072

RESUMO

BACKGROUND: Evolutionary changes in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) include indels in non-structural, structural, and accessory open reading frames (ORFs) or genes. OBJECTIVES: We track indels in accessory ORFs to infer evolutionary gene patterns and epidemiological links between outbreaks. METHODS: Genomes from Coronavirus disease 2019 (COVID-19) case-patients were Illumina sequenced using ARTIC_V3. The assembled genomes were analysed to detect substitutions and indels. FINDINGS: We reported the emergence and spread of a unique 4-nucleotide deletion in the accessory ORF6, an interesting gene with immune modulation activity. The deletion in ORF6 removes one repeat unit of a two 4-nucleotide repeat, which shows that directly repeated sequences in the SARS-CoV-2 genome are associated with indels, even outside the context of extended repeat regions. The 4-nucleotide deletion produces a frameshifting change that results in a protein with two inserted amino acids, increasing the coding information of this accessory ORF. Epidemiological and genomic data indicate that the deletion variant has a single common ancestor and was initially detected in a health care outbreak and later in other COVID-19 cases, establishing a transmission cluster in the Uruguayan population. MAIN CONCLUSIONS: Our findings provide evidence for the origin and spread of deletion variants and emphasise indels' importance in epidemiological studies, including differentiating consecutive outbreaks occurring in the same health facility.


Assuntos
COVID-19 , Fases de Leitura Aberta , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/virologia , Genoma Viral , Humanos , SARS-CoV-2/genética , Deleção de Sequência , Uruguai/epidemiologia
3.
Glob Chang Biol ; 23(6): 2331-2344, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27801530

RESUMO

Lakes at high altitude and latitude are typically unproductive ecosystems where external factors outweigh the relative importance of in-lake processes, making them ideal sentinels of climate change. Climate change is inducing upward vegetation shifts at high altitude and latitude regions that translate into changes in the pools of soil organic matter. Upon mobilization, this allochthonous organic matter may rapidly alter the composition and function of lake bacterial communities. Here, we experimentally simulate this potential climate-change effect by exposing bacterioplankton of two lakes located above the treeline, one in the Alps and one in the subarctic region, to soil organic matter from below and above the treeline. Changes in bacterial community composition, diversity and function were followed for 72 h. In the subarctic lake, soil organic matter from below the treeline reduced bulk and taxon-specific phosphorus uptake, indicating that bacterial phosphorus limitation was alleviated compared to organic matter from above the treeline. These effects were less pronounced in the alpine lake, suggesting that soil properties (phosphorus and dissolved organic carbon availability) and water temperature further shaped the magnitude of response. The rapid bacterial succession observed in both lakes indicates that certain taxa directly benefited from soil sources. Accordingly, the substrate uptake profiles of initially rare bacteria (copiotrophs) indicated that they are one of the main actors cycling soil-derived carbon and phosphorus. Our work suggests that climate-induced changes in soil characteristics affect bacterioplankton community structure and function, and in turn, the cycling of carbon and phosphorus in high altitude and latitude aquatic ecosystems.


Assuntos
Mudança Climática , Microbiologia do Solo , Altitude , Bactérias , Biodiversidade , Clima , Lagos , Solo
4.
Ginecol Obstet Mex ; 83(10): 602-13, 2015 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-26859922

RESUMO

OBJECTIVE: Determine maternal and fetal characteristics of in vitro fertilization twin pregnancies in comparison with spontaneous twin pregnancies. MATERIAL AND METHODS: Retrospective historical cohort study between 2011 and 2013. Statistical analysis was performed with SPSS 15.0 program and Epidat 3.0. A value of p<0.05 was considered statistically significant. RESULTS: 96 twin pregnancies met inclusive criteria with an incidence of 2.01%, of which 54.16% were spontaneous twin pregnancies and 45.83% in vitro fertilization twin pregnancies. Mean maternal age at delivery was higher in vitro fertilization twin pregnancies (p=0.004). The primigravidae were more frequent in vitro fertilization twin pregnancies group (p<0.001). Monochorionic pregnancies percentage was superior in spontaneous pregnancies (p=0.009). Amenorrhea at delivery was not a significant difference between cohorts (p=.9). Preterm rate was superior in spontaneous twin pregnancies group (p=0.003). However, "great preterm deliveries" were higher in in vitro fertilization twin pregnancies (p<0.001). Significant differences were not observed in fetal presentation at delivery, first-born child birth-weight or intrauterine growth retardation between the two groups. Nevertheless, the mean birth-weight of second-born spontaneously conceived twins was higher than second-born twins of the in vitro fertilization conceived group (p=0.027). Gestational pathology presented the same distribution in both cohorts. There was no significant difference in the mode of delivery between the two groups. Total perinatal mortality rate was 20,83%o and comprised 2 first born twins and 2 second born twins. Three of the stillbirths came from the spontaneous pregnancies group and one from the in vitro fertilization group. CONCLUSIONS: Perinatal death was secondary to stillbirths, which we found higher in spontaneously conceived twin pregnancies due to higher number of monochorionic pregnancies.


Assuntos
Fertilização in vitro , Complicações na Gravidez/epidemiologia , Resultado da Gravidez , Gravidez de Gêmeos , Adulto , Peso ao Nascer , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Idade Materna , Pessoa de Meia-Idade , Mortalidade Perinatal , Gravidez , Estudos Retrospectivos , Natimorto/epidemiologia , Gêmeos , Adulto Jovem
5.
Nat Commun ; 15(1): 2640, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38531850

RESUMO

Climate change induced shifts in treeline position, both towards higher altitudes and latitudes induce changes in soil organic matter. Eventually, soil organic matter is transported to alpine and subarctic lakes with yet unknown consequences for dissolved organic matter (DOM) diversity and processing. Here, we experimentally investigate the consequences of treeline shifts by amending subarctic and temperate alpine lake water with soil-derived DOM from above and below the treeline. We use ultra-high resolution mass spectrometry (FT-ICR MS) to track molecular DOM diversity (i.e., chemodiversity), estimate DOM decay and measure bacterial growth efficiency. In both lakes, soil-derived DOM from below the treeline increases lake DOM chemodiversity mainly through the enrichment with polyphenolic and highly unsaturated compounds. These compositional changes are associated with reductions in bulk and compound-level DOM reactivity and reduced bacterial growth efficiency. Our results suggest that treeline advancement has the potential to enrich a large number of lake ecosystems with less biodegradable DOM, affecting bacterial community function and potentially altering the biogeochemical cycling of carbon in lakes at high latitudes and altitudes.


Assuntos
Matéria Orgânica Dissolvida , Lagos , Lagos/química , Ecossistema , Altitude , Solo/química
6.
J Wildl Dis ; 60(1): 105-115, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37909407

RESUMO

In a 2-yr study on prevalence of Haemosporidia in an avian community in Ithaca, New York, USA, we tested the hypothesis that apparent seasonal variation in prevalence is influenced by the detection protocol. We confirmed a higher detection of Haemosporidia using a molecular diagnosis technique (PCR) than by microscopy; this further increased when the PCR test was triplicated. Microscopic examination and PCR techniques have different specificity and sensitivity and therefore different probabilities of detecting hemoparasites. Birds with chronic infections or sampled during winter often have very low parasitemia, and such infections may be missed by microscopy but detected by PCR. Haemosporidian prevalence was higher during the breeding season than during the nonbreeding season regardless of the method used. Detection of Leucocytozoon spp. infection from blood smears using microscopy was challenging.


Assuntos
Doenças das Aves , Haemosporida , Plasmodium , Infecções Protozoárias em Animais , Animais , Estações do Ano , Microscopia/veterinária , Doenças das Aves/parasitologia , Infecções Protozoárias em Animais/diagnóstico , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/parasitologia , Haemosporida/genética , Aves/parasitologia , Reação em Cadeia da Polimerase/veterinária , Reação em Cadeia da Polimerase/métodos , Prevalência , Plasmodium/genética , Filogenia
7.
Prehosp Disaster Med ; 28(2): 104-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23256969

RESUMO

INTRODUCTION: Severe sepsis and septic shock are common and often fatal medical problems. The Prehospital Sepsis Project is a multifaceted study that aims to improve the out-of-hospital care of patients with sepsis by means of education and enhancement of skills. The objective of this Project was to assess the knowledge and attitudes in the principles of diagnosis and management of sepsis in a cohort of United States out-of-hospital care providers. METHODS: This was cross-sectional study. A 15-item survey was administered via the Web and e-mailed to multiple emergency medical services list-servers. The evaluation consisted of four clinical scenarios as well as questions on the basics of sepsis. For intra-rater reliability, the first and the fourth scenarios were identical. Chi-square and Fisher's Exact testing were used to assess associations. Relative risk (RR) was used for strength of association. Statistical significance was set at .05. RESULTS: A total of 226 advanced EMS providers participated with a 85.4% (n = 193) completion rate, consisting of a 30.7% rural, 32.3% urban, and 37.0% suburban mix; 82.4% were paramedics and 72.5% had worked in EMS >10 years. Only 57 (29.5%) participants scored both of the duplicate scenarios correctly, and only 19 of the 193 (9.8%) responded to all scenarios correctly. Level of training was not a predictor of correctly scoring scenarios (P = .71, RR = 1.25, 95% CI = 0.39-4.01), nor was years of service (P = .11, RR = 1.64, 95% CI = 0.16-1.21). CONCLUSIONS: Poor understanding of the principles of diagnosis and management of sepsis was observed in this cohort, suggesting the need for enhancement of education. Survey items will be used to develop a focused, interactive Web-based learning program. Limitations include potential for self-selection and data accuracy.


Assuntos
Serviços Médicos de Emergência , Auxiliares de Emergência , Enfermagem em Emergência , Conhecimentos, Atitudes e Prática em Saúde , Avaliação das Necessidades , Sepse/terapia , Estudos Transversais , Educação a Distância , Auxiliares de Emergência/educação , Enfermagem em Emergência/educação , Humanos , Capacitação em Serviço , Estados Unidos
8.
Cir Esp ; 91(4): 217-23, 2013 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-22541448

RESUMO

Permanent synthetic materials are currently of choice for abdominal wall hernia repair. However, they are not ideal as short- and long-term complications with these have been reported. Extracellular matrix-derived biological implants (EMDBI) have emerged as a result of research and development into new materials. Several types of EMDBI have appeared in the last few years, each with its own manufacture characteristics and different from the rest. The current panorama of the xenogeneic EMDBI available in Spain is analysed, their complications, the unknown factors arising in the long-term, and the clinical experience available on incisional and inguinal hernias.


Assuntos
Bioprótese , Hérnia Abdominal/cirurgia , Herniorrafia/métodos , Telas Cirúrgicas , Humanos
9.
Avian Dis ; 67(1): 42-48, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-37140110

RESUMO

Ever since 1994, when the bacterial pathogen Mycoplasma gallisepticum jumped from poultry to wild birds, it has been assumed that the primary host species of this pathogen in wild North American birds was the house finch (Haemorhous mexicanus), in which disease prevalence was higher than in any other bird species. Here we tested two hypotheses to explain a recent increase in disease prevalence in purple finches (Haemorhous purpureus) around Ithaca, New York. Hypothesis 1 is that, as M. gallisepticum evolved and became more virulent, it has also become better adapted to other finches. If this is correct, early isolates of M. gallisepticum should cause less-severe eye lesions in purple finches than in house finches, while more-recent isolates should cause eye lesions of similar severity in the two species. Hypothesis 2 is that, as house finch abundance declined following the M. gallisepticum epidemic, purple finches around Ithaca increased in abundance relative to house finches and purple finches are thus more frequently exposed to M. gallisepticum-infected house finches. This would then lead to an increase in M. gallisepticum prevalence in purple finches. Following an experimental infection with an early and a more-recent M. gallisepticum isolate, eye lesions in purple finches were more severe than in house finches. This did not a support Hypothesis 1; similarly, an analysis of Project Feeder Watch data collected around Ithaca did not show differences in changes in purple and house finches' abundance since 2006, a result which does not support Hypothesis 2. We conclude that purple finch populations will, unlike those of house finches, not suffer a severe decline because of a M. gallisepticum epidemic.


¿Son los pinzones purpúreos (Haemorhous purpureus) los próximos huéspedes de una epidemia de conjuntivitis por micoplasma? Desde el año 1994, cuando el patógeno bacteriano Mycoplasma gallisepticum saltó de las aves comerciales a las aves silvestres, se ha supuesto que la principal especie huésped de este patógeno en las aves silvestres de América del Norte era el pinzón mexicano (Haemorhous mexicanus), en el que la prevalencia de la enfermedad era mayor que en cualquier otra especie aviar. En este estudio se analizaron dos hipótesis para explicar un aumento reciente en la prevalencia de la enfermedad en los pinzones purpúreos (Haemorhous purpureus) alrededor de Ithaca, en Nueva York. La hipótesis 1 es que, a medida que M. gallisepticum evolucionó y se volvió más virulento, también se adaptó mejor a otros pinzones. Si esto es correcto, los aislamientos tempranos de M. gallisepticum deberían causar lesiones oculares menos graves en los pinzones purpúreos que en los pinzones mexicanos, mientras que los aislamientos más recientes deberían causar lesiones oculares de gravedad similar en las dos especies. La hipótesis 2 es que, a medida que la abundancia de pinzones mexicanos disminuyó después de la epidemia de M. gallisepticum, los pinzones purpúreos alrededor de Ithaca aumentaron en abundancia en relación con los pinzones mexicanos y, por lo tanto, los pinzones morados están expuestos con mayor frecuencia a los pinzones caseros infectados con M. gallisepticum. Esto conduciría a un aumento de la prevalencia de M. gallisepticum en los pinzones purpúreos. Después de una infección experimental con un aislamiento temprano y uno más reciente de M. gallisepticum, las lesiones oculares en los pinzones purpúreos fueron más graves que en los pinzones mexicanos. Esto no apoyó la Hipótesis 1; de manera similar, un análisis de los datos del Proyecto Feeder Watch recopilados alrededor de Ithaca no mostró diferencias en los cambios de la abundancia de pinzones purpúreos y mexicanos desde 2006, un resultado que no respalda la Hipótesis 2. Se concluye que las poblaciones de pinzones purpúreos, a diferencia de las de los pinzones mexicanos, no sufrieron un declive severo a causa de una epidemia de M. gallisepticum.


Assuntos
Doenças das Aves , Conjuntivite , Tentilhões , Infecções por Mycoplasma , Mycoplasma gallisepticum , Doenças das Aves Domésticas , Animais , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/veterinária , Infecções por Mycoplasma/microbiologia , Doenças das Aves/epidemiologia , Doenças das Aves/microbiologia , Conjuntivite/veterinária
10.
J Am Chem Soc ; 134(8): 3639-42, 2012 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-22320198

RESUMO

Asymmetric multicomponent nanoparticles (AMNPs) offer new opportunities for new-generation materials with improved or new synergetic properties not found in their individual components. There is, however, an urgent need for a synthetic strategy capable of preparing hybrid AMNPs with fine-tuned structural and compositional complexities. Herein, we report a new paradigm for the controllable synthesis of polymer/metal AMNPs with well-controlled size, shape, composition, and morphology by utilizing interfacial polymerization. The hybrid AMNPs display a new level of structural-architectural sophistication, such as controlled domain size and the number of each component of AMNPs. The approach is simple, versatile, cost-effective, and scalable for synthesizing large quantities of AMNPs. Our method may pave a new route to the design and synthesis of advanced breeds of building blocks for functional materials and devices.


Assuntos
Nanopartículas/química , Compostos Organometálicos/síntese química , Ouro/química , Compostos Organometálicos/química , Tamanho da Partícula , Polímeros/química , Propriedades de Superfície
11.
J Wildl Dis ; 58(4): 716-724, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36302353

RESUMO

Mycoplasma gallisepticum, a pathogen of worldwide economic importance in poultry, is recovered in chickens, especially from the respiratory tract. Some strains, however, are specialized to other tissues and because it jumps from poultry to wild birds, the new strains also cause severe conjunctivitis in new hosts. Nevertheless, most studies of M. gallisepticum in wild birds use choanal swabs or combine choanal and conjunctival swabs to quantify bacterial load. Because the clinical signs associated with M. gallisepticum infection differ markedly between poultry and House Finches (Haemorhous mexicanus), we compared the bacterial load in choanal and conjunctival samples following experimental inoculation of House Finches with M. gallisepticum isolates originating from poultry or from House Finches. This allowed us to test two hypotheses: M. gallisepticum changed tissue tropism, or M. gallisepticum simply expanded its within-host niche. By comparing bacterial loads from choanal and conjunctival swabs in birds inoculated with one of a suite of M. gallisepticum isolates, we found support for hypothesis 2. The choanal loads in House Finches did not differ between isolates, while the conjunctival loads of birds inoculated with poultry isolates were lower than in birds inoculated with House Finch isolates. When measuring the bacterial load of M. gallisepticum in birds, it is important to sample and analyze separately choanal and conjunctival swabs, as quantifying bacterial loads in pooled samples may not provide reliable information on differences in virulence.


Assuntos
Mycoplasma gallisepticum , Animais , Galinhas
12.
Vaccine ; 40(13): 1958-1967, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35193792

RESUMO

SARS-CoV-2, the cause of the COVID-19 pandemic, has provoked a global crisis and death of millions of people. Several serological assays to determine the quality of the immune response against SARS-CoV-2 and the efficacy of vaccines have been developed, among them the gold standard conventional virus neutralization assays. However, these tests are time consuming, require biosafety level 3 (BSL3), and are low throughput and expensive. This has motivated the development of alternative methods, including molecular inhibition assays. Herein, we present a safe cell-based ELISA-virus neutralization test (cbE-VNT) as a surrogate for the conventional viral neutralization assays that detects the inhibition of SARS-CoV-2 RBD binding to ACE2-bearing cells independently of species. Our test shows a very good correlation with the conventional and molecular neutralization assays and achieves 100% specificity and 95% sensitivity. cbE-VNT is cost-effective, fast and enables a large-scale serological evaluation that can be performed in a BSL2 laboratory, allowing its use in pre-clinical and clinical investigations.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Testes de Neutralização/métodos , Pandemias/prevenção & controle , Glicoproteína da Espícula de Coronavírus
13.
J Wildl Dis ; 58(3): 512-523, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35704503

RESUMO

Research on host response to infectious disease often involves pharmacological induction of immunosuppression, frequently through administration of dexamethasone. Reports on the effect of dexamethasone in birds are largely restricted to poultry and pigeons. This study describes changes in white blood cell (WBC) differentials, hemoparasite counts, splenic histology, and splenic CD3 immunoreactivity in House Finches (Haemorhous mexicanus). Experimental group birds (n=9) were treated with a daily intramuscular injection of 25 µg of dexamethasone for 8 d; a control group (n=9) received daily saline solution. Smears were made with blood collected immediately before the first dose (day 0) and on d 4, 8, and 9, and stained with modified Wright. The WBC differential counts were performed by three blinded observers, parasite counts by two blinded observers, and histology by one blinded observer. Dexamethasone-treated birds experienced relative heterophilia and lymphopenia on d 4 (P=0.008); heterophilia was also present at d 8 (P=0.018). Hemosporidian counts were significantly increased in dexamethasone-treated birds on d 4 and 8 (P=0.048 and P=0.031, respectively). In contrast with control birds, all dexamethasone-treated birds lacked histologically apparent splenic lymphoid follicles (P<0.001). No significant difference was observed in splenic CD3 immunoreactivity between groups. Our results indicate that dexamethasone has an effect on the hematologic profile of House Finches and suggest that it may be a useful method to induce immunosuppression in this species.


Assuntos
Doenças das Aves , Tentilhões , Infecções por Mycoplasma , Animais , Doenças das Aves/tratamento farmacológico , Dexametasona/farmacologia , Tentilhões/fisiologia , Infecções por Mycoplasma/veterinária
14.
Environ Microbiol ; 12(1): 74-82, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19725866

RESUMO

We examined the ability of different freshwater bacterial groups to take up leucine and thymidine in two lakes. Utilization of both substrates by freshwater bacteria was examined at the community level by looking at bulk incorporation rates and at the single-cell level by combining fluorescent in situ hybridization and signal amplification by catalysed reporter deposition with microautoradiography. Our results showed that leucine was taken up by 70-80% of Bacteria-positive cells, whereas only 15-43% of Bacteria-positive cells were able to take up thymidine. When a saturating substrate concentration in combination with a short incubation was used, 80-90% of Betaproteobacteria and 67-79% of Actinobacteria were positive for leucine uptake, whereas thymidine was taken up by < 10% of Betaproteobacteria and by < 1% of the R-BT subgroup that dominated this bacterial group. Bacterial abundance was a good predictor of the relative contribution of bacterial groups to leucine uptake, whereas when thymidine was used Actinobacteria represented the large majority (> 80%) of the cells taking up this substrate. Increasing the substrate concentration to 100 nM did not affect the percentage of R-BT cells taking up leucine (> 90% even at low concentrations), but moderately increased the fraction of thymidine-positive R-BT cells to a maximum of 35% of the hybridized cells. Our results show that even at very high concentrations, thymidine is not taken up by all, otherwise active, bacterial cells.


Assuntos
Bactérias/metabolismo , Leucina/metabolismo , Timidina/metabolismo , Microbiologia da Água , Actinobacteria/crescimento & desenvolvimento , Actinobacteria/metabolismo , Bactérias/crescimento & desenvolvimento , Técnicas de Tipagem Bacteriana , Betaproteobacteria/crescimento & desenvolvimento , Betaproteobacteria/metabolismo , Contagem de Colônia Microbiana , Água Doce/microbiologia , Temperatura
15.
Limnol Oceanogr ; 55(3): 1134-1144, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20401318

RESUMO

We assessed the physicochemical properties of the surface microlayer (SML: first 900 µm) and its underlying water (ULW: 0.2-0.5-m depth) and compared the composition and activity of their bacterial communities in six lakes located across an altitude gradient. Activity was assessed at both the community level, by measuring leucine bulk incorporation, and at the single-cell level, by using microautoradiography. Catalyzed reporter deposition fluorescence in situ hybridization was used to quantitatively assess the structure of the bacterial assemblage. Dissolved organic matter at the SML was significantly enriched in small-size molecules as compared to the ULW. Bacterial abundance in the SML ranged from 3.2 × 10(5) cells mL(-1) to 3.2 × 10(6) cells mL(-1) and was enriched in four out of six lakes when compared to the ULW. The SML and ULW showed lake-specific differences in bacterial community composition, although in most cases, both layers were dominated by Betaproteobacteria. This group also contributed the most to total activity in both layers in all lakes, followed by Actinobacteria. Despite large differences in environmental conditions among lakes, the fraction of active neustonic bacteria was very similar in most of them. Both bulk and single-cell activities are not necessarily lower in the SML than in the ULW, and well-adapted bacteria exist in the extreme conditions found in this habitat.

16.
Aten Primaria ; 42(5): 284-91, 2010 May.
Artigo em Espanhol | MEDLINE | ID: mdl-19944493

RESUMO

OBJECTIVE: To determine the effectiveness of multifactorial intervention by Primary Care in the prevention of falls in the elderly who had fallen the year before. DESIGN: Intervention study with a control group. SETTING: Three clinics in a rural area. SUBJECTS: 224 patients > or = 65 years, independent for mobility (113 in the intervention (IG) and 111 in the control (GC) group. INTERVENTIONS: Intervention Group. INITIAL ASSESSMENT: 1) Demographic data questionnaire, number, circumstances and consequences of falls, comorbidity and drugs. 2) Oriented examination. 3) Home risks assessment. INTERVENTIONS: referred to cardiology if arrhythmia or bradycardia, referred for eye examination if changes in acute vision, recommendation for systems support if gait or balance problems, postural measures if orthostatic hypotension, behavioural measures in urinary incontinence and recommendations to modify home risks. CONTROL GROUP: Questionnaire on: demographic data, number, circumstances and consequences of falls and medication use. They received normal medical care. RESULTS: At one year 44% of the IG and 33% in the CG fell again (P=0.123). In the sub-group with more than one fall at the beginning of the study, 63% in the IG, and 56% in CG fell again (P=0.599). There were serious consequences in 6% of the IG compared to 14% in the CG (P=0.277). CONCLUSIONS: Multifactorial intervention from primary care is not effective in reducing falls or for reducing the severity of their consequences.


Assuntos
Acidentes por Quedas/prevenção & controle , Idoso , Feminino , Humanos , Masculino , Atenção Primária à Saúde , Inquéritos e Questionários
17.
Int J Parasitol Parasites Wildl ; 12: 53-63, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32426219

RESUMO

Hosts are typically co-parasitized by multiple species. Parasites can benefit or suffer from the presence of other parasites, which can reduce or increase the overall virulence due to competition or facilitation. Outcomes of new multi-parasite systems are seldom predictable. In 1994 the bacterium Mycoplasma gallisepticum jumped from poultry to songbirds in which it caused an epidemic throughout North America. Songbirds are often parasitized by hard ticks, and can act as reservoirs for tick-borne pathogens. We tested the hypothesis that Mycoplasma infection in house finches influences North America's most important tick vector Ixodes scapularis, by affecting the tick's feeding success, detachment behaviour and survival to the next stage. Most ticks detached during the daylight hours irrespective of the bird's disease status and time since infestation. Birds incrementally invested in anti-tick resistance mechanisms over the course of the experiment; this investment was made earlier in the Mycoplasma-infected birds. At higher tick densities, the feeding success on birds with more severe conjunctivitis was lower than in the uninfected birds. Throughout the experiment we found positive density dependent effects on the tick's feeding success. More diseased hosts suffered more from the tick infestations, as shown by reduced haematocrits. Three Mycoplasma-infected birds died during the weeks following the experiment, although all birds were kept in optimal housing conditions. Mycoplasma made the bird a less accessible and valuable host for ticks, which is an example of ecological interference. Therefore, Mycoplasma has the potential to ultimately reduce transmission outcomes of tick-borne pathogens via songbird hosts.

18.
Ecol Evol ; 10(12): 5801-5814, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32607191

RESUMO

Hosts are typically coinfected by multiple parasite species whose interactions might be synergetic or antagonistic, producing unpredictable physiological and pathological impacts on the host. This study shows the interaction between Plasmodium spp. and Leucocytozoon spp. in birds experimentally infected or not infected with Mycoplasma gallisepticum.In 1994, the bacterium Mycoplasma gallisepticum jumped from poultry to wild birds in which it caused a major epidemic in North America. Birds infected with M. gallisepticum show conjunctivitis as well as increased levels of corticosterone.Malaria and other haemosporidia are widespread in birds, and chronic infections become apparent with the detectable presence of the parasite in peripheral blood in response to elevated levels of natural or experimental corticosterone levels.Knowing the immunosuppressive effect of corticosterone on the avian immune system, we tested the hypothesis that chronic infections of Plasmodium spp. and Leucocytozoon spp. in house finches would respond to experimental inoculation with M. gallisepticum as corticosterone levels are known to increase following inoculation. Plasmodium spp. infection intensity increased within days of M. gallisepticum inoculation as shown both by the appearance of infected erythrocytes and by the increase in the number and the intensity of positive PCR tests. Leucocytozoon spp. infection intensity increased when Plasmodium spp. infection intensity increased, but not in response to M. gallisepticum inoculation. Leucocytozoon spp. and Plasmodium spp. seemed to compete in the host as shown by a negative correlation between the changes in their PCR score when both pathogens were present in the same individual.Host responses to coinfection with multiple pathogens measured by the hematocrit and white blood cell count depended on the haemosporidian community composition. Host investment in the leukocyte response was higher in the single-haemosporidia-infected groups when birds were infected with M. gallisepticum.A trade-off was observed between the immune control of the chronic infection (Plasmodium spp./Leucocytozoon spp.) and the immune response to the novel bacterial infection (M. gallisepticum).

19.
Rev Esp Salud Publica ; 932019 Aug 06.
Artigo em Espanhol | MEDLINE | ID: mdl-31378780

RESUMO

OBJECTIVE: Informal care affects the quality of life and emotional health. Objective: To analyze the relationship between burden and depression in caregivers measured by Zarit's Scale and GHQ-28 and the global functional deterioration of the elderly measured by OARS-MFAQ. METHODS: Descriptive observational cross-sectional study in Primary Health Care at Ourense city. 104 people (>65 years old) and their caregivers were interviewed. Descriptive analysis and logistic regression were used to analyze the characteristics that increase the probability to suffer burden and depression. RESULTS: 82.7% of caregivers were women with an average age of 63.64 years (95% CI: 61.05-66.23) and 10.3% were over 80 years old. 32.2% had an overload, associated with taking care of younger people (p=0.043), being a couple of an elder (p=0.003) being older (p=0.031) and the risk of depression which were all found as factors associated with burden, measured by GHQ (p<0.001). Having good perception of the vision (p=0.038), rejecting the use of a cane (p=0.002) or wheelchair (p=0.015) were also associated with factors contributing to burden. CONCLUSIONS: Informal caregivers are women around their sixties, and although they do not feel overburdened for caring, they have depression, more likely the more severe the burden is, and it is related with the perception of economic deficiencies for the caring.


OBJETIVO: Los cuidados informales afectan a la calidad de vida y a la salud emocional. El objetivo de este trabajo fue analizar la relación entre la carga y la depresión en los cuidadores/as medida con Escala de Zarit y GHQ-28 y el deterioro funcional global del anciano medido mediante OARS-MFAQ. METODOS: Estudio transversal descriptivo por entrevistas a 104 personas mayores de 65 años y sus cuidadores/as informales en la ciudad de Ourense. Se realizó un análisis descriptivo y una regresión logística de las variables que influyen en la depresión y la sobrecarga por cuidar ancianos. RESULTADOS: El 82,7% de cuidadores/as eran mujeres con edad media de 63,64 años (IC 95%: 61,05-66,23) y el 10,3% mayor de 80 años. El 32,2% presentaba sobrecarga encontrándose como factores asociados a la misma, cuidar de ancianos más jóvenes (p=0,043), ser pareja del anciano (p=0,003), tener mayor edad (p=0,031) y el riesgo de depresión medida con GHQ (p<0,001). Tener buena percepción de la visión (p=0,038), rechazar el uso de bastón (p=0,002) o silla de ruedas (p=0,015) también se asoció con la sobrecarga. CONCLUSIONES: Las cuidadoras informales son mujeres en torno a 60 años. Aunque no sientan sobrecarga por cuidar, tienen depresión, que es más probable cuanto más severa es la carga y esta se relaciona con la percepción de carencias económicas básicas para el cuidado.


Assuntos
Adaptação Psicológica , Envelhecimento , Cuidadores/psicologia , Depressão/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Emoções , Feminino , Humanos , Modelos Logísticos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Assistência ao Paciente , Atenção Primária à Saúde , Qualidade de Vida , Espanha
20.
Artigo em Inglês | MEDLINE | ID: mdl-30418903

RESUMO

The Fast Marching method is widely employed in several fields of image processing. Some years ago a Multi-Stencil version (MSFM) was introduced to improve its accuracy by solving the equation for a set of stencils and choosing the best solution at each considered node. The following work proposes a modified numerical scheme for MSFM to take into account the variation of the local cost, which has proven to be second order. The influence of the stencil set choice on the algorithm outcome with respect to stencil orthogonality and axis swapping is also explored, where stencils are taken from neighborhoods of varying radius. The experimental results show that the proposed schemes improve the accuracy of their original counterparts, and that the use of permutation-invariant stencil sets provides robustness against shifted vector coordinates in the stencil set.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA