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1.
Sensors (Basel) ; 21(20)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34695965

RESUMO

Effective ocean management requires integrated and sustainable ocean observing systems enabling us to map and understand ecosystem properties and the effects of human activities. Autonomous subsurface and surface vehicles, here collectively referred to as "gliders", are part of such ocean observing systems providing high spatiotemporal resolution. In this paper, we present some of the results achieved through the project "Unmanned ocean vehicles, a flexible and cost-efficient offshore monitoring and data management approach-GLIDER". In this project, three autonomous surface and underwater vehicles were deployed along the Lofoten-Vesterålen (LoVe) shelf-slope-oceanic system, in Arctic Norway. The aim of this effort was to test whether gliders equipped with novel sensors could effectively perform ecosystem surveys by recording physical, biogeochemical, and biological data simultaneously. From March to September 2018, a period of high biological activity in the area, the gliders were able to record a set of environmental parameters, including temperature, salinity, and oxygen, map the spatiotemporal distribution of zooplankton, and record cetacean vocalizations and anthropogenic noise. A subset of these parameters was effectively employed in near-real-time data assimilative ocean circulation models, improving their local predictive skills. The results presented here demonstrate that autonomous gliders can be effective long-term, remote, noninvasive ecosystem monitoring and research platforms capable of operating in high-latitude marine ecosystems. Accordingly, these platforms can record high-quality baseline environmental data in areas where extractive activities are planned and provide much-needed information for operational and management purposes.


Assuntos
Ecossistema , Salinidade , Humanos , Oceanos e Mares
2.
Biol Rev Camb Philos Soc ; 96(4): 1547-1589, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33942990

RESUMO

Vertical migration is a geographically and taxonomically widespread behaviour among zooplankton that spans across diel and seasonal timescales. The shorter-term diel vertical migration (DVM) has a periodicity of up to 1 day and was first described by the French naturalist Georges Cuvier in 1817. In 1888, the German marine biologist Carl Chun described the longer-term seasonal vertical migration (SVM), which has a periodicity of ca. 1 year. The proximate control and adaptive significance of DVM have been extensively studied and are well understood. DVM is generally a behaviour controlled by ambient irradiance, which allows herbivorous zooplankton to feed in food-rich shallower waters during the night when light-dependent (visual) predation risk is minimal and take refuge in deeper, darker waters during daytime. However, DVMs of herbivorous zooplankton are followed by their predators, producing complex predator-prey patterns that may be traced across multiple trophic levels. In contrast to DVM, SVM research is relatively young and its causes and consequences are less well understood. During periods of seasonal environmental deterioration, SVM allows zooplankton to evacuate shallower waters seasonally and take refuge in deeper waters often in a state of dormancy. Both DVM and SVM play a significant role in the vertical transport of organic carbon to deeper waters (biological carbon sequestration), and hence in the buffering of global climate change. Although many animal migrations are expected to change under future climate scenarios, little is known about the potential implications of global climate change on zooplankton vertical migrations and its impact on the biological carbon sequestration process. Further, the combined influence of DVM and SVM in determining zooplankton fitness and maintenance of their horizontal (geographic) distributions is not well understood. The contrasting spatial (deep versus shallow) and temporal (diel versus seasonal) scales over which these two migrations occur lead to challenges in studying them at higher spatial, temporal and biological resolution and coverage. Extending the largely population-based vertical migration knowledge base to individual-based studies will be an important way forward. While tracking individual zooplankton in their natural habitats remains a major challenge, conducting trophic-scale, high-resolution, year-round studies that utilise emerging field sampling and observation techniques, molecular genetic tools and computational hardware and software will be the best solution to improve our understanding of zooplankton vertical migrations.


Assuntos
Migração Animal , Zooplâncton , Animais , Ecossistema , Comportamento Predatório
3.
Can J Infect Dis Med Microbiol ; 2018: 9704532, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30123395

RESUMO

OBJECTIVES: The aim of this study was to determine the level of five different pro- and anti-inflammatory cytokines to study the inflammatory response of leptospirosis. MATERIALS AND METHODS: The serum cytokine levels of IL-10, IL-17A, IL-21, IL-23, and TNF-α were investigated in 57 patients with leptospirosis and 12 healthy controls using a commercially available ELISA kit (Mabtech, Sweden). Statistical analysis was done using Graphpad Prism. RESULTS: Elevation of serum IL-10 and IL-17A levels and significant elevation of serum IL-21 (p=0.002), IL-23 (p=0.002), and TNF-α (p=0.039) were observed among leptospirosis patients compared to the healthy control group. The two major complications observed among these patients were renal failure and liver involvement. Renal failure was significantly associated with elevation of IL-21 and IL-23, while patients with liver involvement had a significant elevation of IL-21, IL-23, and TNF-α. CONCLUSION: Elevation of IL-17A together with the significant elevation of IL-21 and IL-23 suggests a possible involvement of Th17 cells in the immunopathogenesis of leptospirosis.

4.
Microrna ; 6(2): 80-96, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28294076

RESUMO

MicroRNAs (miRNAs) are 17-22 nucleotide, non-coding, single stranded RNA molecules that play a key role in post-transcriptional gene regulation. Hypoxia is a reduction in the normal level of tissue oxygen (O2) tension, and is a feature of chronic vascular disease, pulmonary disease and many cancers. Tissue hypoxia can have widespread effects on cellular functions, as O2 availability is critical for many cellular processes. Cells respond to changes in O2 tension through multiple molecular and cellular mechanisms, including changes in gene expression through transcriptional and translational mechanisms. The transcription factor, hypoxia inducible factor-1, plays a dominant role in transcriptional gene regulation in hypoxia. Several hypoxically induced miRNAs have been shown to play important roles in the hypoxic adaptation of cancer cells. Global repression of enzymes critical for miRNA biogenesis seems to be a widespread phenomenon with several different mechanisms operating. This review describes the effects of hypoxia on specific miRNAs and more global effects on miRNA biogenesis, demonstrating that hypoxia is an important regulator of miRNA biogenesis and function.


Assuntos
Regulação da Expressão Gênica , Hipóxia/genética , MicroRNAs/biossíntese , Adaptação Fisiológica , Animais , Humanos , Hipóxia/fisiopatologia , MicroRNAs/genética , Oxigênio/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo
5.
BMC Infect Dis ; 16(1): 446, 2016 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-27554098

RESUMO

BACKGROUND: Leptospirosis is a globally emerging zoonotic disease and an important public health threat in developing countries. Diagnosis of leptospirosis is mainly based on clinical presentations in resource poor countries. World Health Organization (WHO) has introduced "Faine's criteria" for diagnosis of leptospirosis. This study was conducted to evaluate the usefulness of modified Faine's criteria (with amendment) 2012 to detect leptospirosis in resource poor settings. METHODS: Blood samples of 168 patients who fulfilled the inclusion criteria admitted between January 2013 to January 2014 were tested by a commercial immunochromatographic assay (Leptocheck WB, India), microscopic agglutination test (MAT) and polymerase chain reaction (PCR) methods. Leptospirosis was confirmed by a single MAT titre ≥1:400 and / or by a positive PCR. Diagnosis of leptospirosis was made using the clinical, epidemiological and laboratory data according to modified Faine's criteria (with amendment) 2012. RESULTS: Leptospirosis was confirmed in 39 % (n = 66) by MAT and/or PCR. When modified Faine's criteria (MAT ≥ 1.400 &/ or PCR), was evaluated against LERG confirmed cases sensitivity, specificity, positive predictive value and negative predictive values were 95.45 %, 56.86 %, 58.88 %, 95.08 % respectively. The modified Faine's criteria with rapid immunochromatographic assay only had a sensitivity, specificity, positive predictive value and negative predictive value 89.39 %, 58.82 %, 58.42 %, and 89.55 % respectively. CONCLUSION: The modified Faine's criteria which utilized only immunochromatographic assay (leptocheck IgM) in Part C was found to be useful tool for diagnosing leptospirosis in a resource poor setting.


Assuntos
Cromatografia de Afinidade/métodos , Leptospirose/diagnóstico , Reação em Cadeia da Polimerase/métodos , Testes de Aglutinação/métodos , Animais , Países em Desenvolvimento , Fazendeiros , Humanos , Leptospira/genética , Leptospira/patogenicidade , Leptospirose/etiologia , Sensibilidade e Especificidade , Sri Lanka , Organização Mundial da Saúde , Zoonoses/diagnóstico
6.
Mem Inst Oswaldo Cruz ; 110(4): 485-91, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26061234

RESUMO

Leptospirosis is a re-emerging zoonotic disease all over the world, important in tropical and subtropical areas. A majority of leptospirosis infected patients present as subclinical or mild disease while 5-10% may develop severe infection requiring hospitalisation and critical care. It is possible that several factors, such as the infecting serovar, level of leptospiraemia, host genetic factors and host immune response, may be important in predisposition towards severe disease. Different Leptospira strains circulate in different geographical regions contributing to variable disease severity. Therefore, it is important to investigate the circulating strains at geographical locations during each outbreak for epidemiological studies and to support the clinical management of the patients. In this study immunochromatography, microscopic agglutination test and polymerase chain reaction were used to diagnose leptospirosis. Further restriction fragment length polymorphism and DNA sequencing methods were used to identify the circulating strains in two selected geographical regions of Sri Lanka. Leptospira interrogans, Leptospira borgpetersenii and Leptospira kirschneri strains were identified to be circulating in western and southern provinces. L. interrogans was the predominant species circulating in western and southern provinces in 2013 and its presence was mainly associated with renal failure.


Assuntos
Leptospira/genética , Leptospirose/microbiologia , Adolescente , Adulto , Testes de Aglutinação , Animais , Cromatografia de Afinidade , Feminino , Humanos , Leptospira/classificação , Leptospira/isolamento & purificação , Leptospira interrogans , Leptospirose/epidemiologia , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Genético , Estudos Prospectivos , Análise de Sequência de DNA , Índice de Gravidade de Doença , Especificidade da Espécie , Sri Lanka/epidemiologia
7.
Mem. Inst. Oswaldo Cruz ; 110(4): 485-491, 09/06/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-748871

RESUMO

Leptospirosis is a re-emerging zoonotic disease all over the world, important in tropical and subtropical areas. A majority of leptospirosis infected patients present as subclinical or mild disease while 5-10% may develop severe infection requiring hospitalisation and critical care. It is possible that several factors, such as the infecting serovar, level of leptospiraemia, host genetic factors and host immune response, may be important in predisposition towards severe disease. Different Leptospira strains circulate in different geographical regions contributing to variable disease severity. Therefore, it is important to investigate the circulating strains at geographical locations during each outbreak for epidemiological studies and to support the clinical management of the patients. In this study immunochromatography, microscopic agglutination test and polymerase chain reaction were used to diagnose leptospirosis. Further restriction fragment length polymorphism and DNA sequencing methods were used to identify the circulating strains in two selected geographical regions of Sri Lanka. Leptospira interrogans, Leptospira borgpetersenii and Leptospira kirschneri strains were identified to be circulating in western and southern provinces. L. interrogans was the predominant species circulating in western and southern provinces in 2013 and its presence was mainly associated with renal failure.


Assuntos
Adolescente , Adulto , Animais , Feminino , Humanos , Masculino , Leptospira/genética , Leptospirose/microbiologia , Testes de Aglutinação , Cromatografia de Afinidade , Leptospira interrogans , Leptospira/classificação , Leptospira/isolamento & purificação , Leptospirose/epidemiologia , Reação em Cadeia da Polimerase , Polimorfismo Genético , Estudos Prospectivos , Análise de Sequência de DNA , Índice de Gravidade de Doença , Especificidade da Espécie , Sri Lanka/epidemiologia
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