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1.
Braz. j. biol ; 83: e248975, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1339377

ABSTRACT

Abstract Colletotrichum is one of the most economically important fungal genera, which affects a wide range of hosts, specifically tropical and subtropical crops. Thus far, there have been several records of mycovirus infection in Colletotrichum spp., primarily by viruses of the Partitiviridae family. There have also been records of infections by mycoviruses of the Chrysoviridae family. Mycoviruses are (+)ssRNA and dsRNA genome viruses, which may or may not be enveloped. To date, no mycovirus with a DNA genome has been isolated from Colletotrichum spp. Typically, mycoviruses cause latent infections, although hypo- and hypervirulence have also been reported in Colletotrichum spp. In addition to its effects on pathogenic behavior, mycovirus infection can lead to important physiological changes, such as altered morphological characteristics, reduced vegetative growth, and suppressed conidia production. Therefore, research on mycoviruses infecting phytopathogenic fungi can help develop alternative methods to chemical control, which can cause irreversible damage to humans and the environment. From an agricultural perspective, mycoviruses can contribute to sustainable agriculture as biological control agents via changes in fungal physiology, ultimately resulting in the total loss of or reduction in the virulence of these pathogens.


Resumo Colletotrichum é um dos gêneros fúngicos mais importantes economicamente, afetando uma ampla gama de hospedeiros, especialmente em cultivos tropicais e subtropicais. Atualmente já existem diversos registros de infecção por micovírus em Colletotrichum spp., sendo a maioria dos já identificados classificados na família Partitiviridae. Ocorrem registros também de micovírus pertencentes à família Chrysoviridae. Compreendem vírus de genoma de (+)ssRNA e dsRNA que podem ser ou não envelopados. Ainda não foram identificados micovírus com genoma de DNA isolados de Colletotrichum. A infecção por micovírus pode ocorrer de forma latente, mas já foi observado em Colletotrichum spp. o fenômeno de hipo e hipervirulência. Além de influenciar no comportamento patogênico, a infecção pode causar mudanças fisiológicas importantes como alterações das características morfológicas, redução do crescimento vegetativo e redução na produção de conídios. O estudo com micovírus em fungos fitopatogênicos traz uma alternativa ao controle químico que é um método capaz de causar danos irreversíveis ao homem e o meio ambiente. Sob a perspectiva agrícola, os micovírus podem contribuir para agricultura sustentável como agentes de controle biológico. Isso porque obsevam-se mudanças importantes na fisiologia fúngica resultando na perda total ou redução da virulência desses patógenos.


Subject(s)
Humans , RNA Viruses , Colletotrichum , Fungal Viruses/genetics , Phylogeny , Spores, Fungal , Virulence
2.
Braz. j. biol ; 83: 1-12, 2023. tab, ilus, graf
Article in English | LILACS, VETINDEX | ID: biblio-1468940

ABSTRACT

Colletotrichum is one of the most economically important fungal genera, which affects a wide range of hosts, specifically tropical and subtropical crops. Thus far, there have been several records of mycovirus infection in Colletotrichum spp., primarily by viruses of the Partitiviridae family. There have also been records of infections by mycoviruses of the Chrysoviridae family. Mycoviruses are (+)ssRNA and dsRNA genome viruses, which may or may not be enveloped. To date, no mycovirus with a DNA genome has been isolated from Colletotrichum spp. Typically, mycoviruses cause latent infections, although hypo- and hypervirulence have also been reported in Colletotrichum spp. In addition to its effects on pathogenic behavior, mycovirus infection can lead to important physiological changes, such as altered morphological characteristics, reduced vegetative growth, and suppressed conidia production. Therefore, research on mycoviruses infecting phytopathogenic fungi can help develop alternative methods to chemical control, which can cause irreversible damage to humans and the environment. From an agricultural perspective, mycoviruses can contribute to sustainable agriculture as biological control agents via changes in fungal physiology, ultimately resulting in the total loss of or reduction in the virulence of these pathogens.


Colletotrichum é um dos gêneros fúngicos mais importantes economicamente, afetando uma ampla gama de hospedeiros, especialmente em cultivos tropicais e subtropicais. Atualmente já existem diversos registros de infecção por micovírus em Colletotrichum spp., sendo a maioria dos já identificados classificados na família Partitiviridae. Ocorrem registros também de micovírus pertencentes à família Chrysoviridae. Compreendem vírus de genoma de (+)ssRNA e dsRNA que podem ser ou não envelopados. Ainda não foram identificados micovírus com genoma de DNA isolados de Colletotrichum. A infecção por micovírus pode ocorrer de forma latente, mas já foi observado em Colletotrichum spp. o fenômeno de hipo e hipervirulência. Além de influenciar no comportamento patogênico, a infecção pode causar mudanças fisiológicas importantes como alterações das características morfológicas, redução do crescimento vegetativo e redução na produção de conídios. O estudo com micovírus em fungos fitopatogênicos traz uma alternativa ao controle químico que é um método capaz de causar danos irreversíveis ao homem e o meio ambiente. Sob a perspectiva agrícola, os micovírus podem contribuir para agricultura sustentável como agentes de controle biológico. Isso porque obsevam-se mudanças importantes na fisiologia fúngica resultando na perda total ou redução da virulência desses patógenos.


Subject(s)
Animals , Colletotrichum/virology , Pest Control, Biological/methods , Fungal Viruses
3.
Braz. j. biol ; 832023.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469156

ABSTRACT

Abstract Colletotrichum is one of the most economically important fungal genera, which affects a wide range of hosts, specifically tropical and subtropical crops. Thus far, there have been several records of mycovirus infection in Colletotrichum spp., primarily by viruses of the Partitiviridae family. There have also been records of infections by mycoviruses of the Chrysoviridae family. Mycoviruses are (+)ssRNA and dsRNA genome viruses, which may or may not be enveloped. To date, no mycovirus with a DNA genome has been isolated from Colletotrichum spp. Typically, mycoviruses cause latent infections, although hypo- and hypervirulence have also been reported in Colletotrichum spp. In addition to its effects on pathogenic behavior, mycovirus infection can lead to important physiological changes, such as altered morphological characteristics, reduced vegetative growth, and suppressed conidia production. Therefore, research on mycoviruses infecting phytopathogenic fungi can help develop alternative methods to chemical control, which can cause irreversible damage to humans and the environment. From an agricultural perspective, mycoviruses can contribute to sustainable agriculture as biological control agents via changes in fungal physiology, ultimately resulting in the total loss of or reduction in the virulence of these pathogens.


Resumo Colletotrichum é um dos gêneros fúngicos mais importantes economicamente, afetando uma ampla gama de hospedeiros, especialmente em cultivos tropicais e subtropicais. Atualmente já existem diversos registros de infecção por micovírus em Colletotrichum spp., sendo a maioria dos já identificados classificados na família Partitiviridae. Ocorrem registros também de micovírus pertencentes à família Chrysoviridae. Compreendem vírus de genoma de (+)ssRNA e dsRNA que podem ser ou não envelopados. Ainda não foram identificados micovírus com genoma de DNA isolados de Colletotrichum. A infecção por micovírus pode ocorrer de forma latente, mas já foi observado em Colletotrichum spp. o fenômeno de hipo e hipervirulência. Além de influenciar no comportamento patogênico, a infecção pode causar mudanças fisiológicas importantes como alterações das características morfológicas, redução do crescimento vegetativo e redução na produção de conídios. O estudo com micovírus em fungos fitopatogênicos traz uma alternativa ao controle químico que é um método capaz de causar danos irreversíveis ao homem e o meio ambiente. Sob a perspectiva agrícola, os micovírus podem contribuir para agricultura sustentável como agentes de controle biológico. Isso porque obsevam-se mudanças importantes na fisiologia fúngica resultando na perda total ou redução da virulência desses patógenos.

4.
Braz J Biol ; 83: e248975, 2021.
Article in English | MEDLINE | ID: mdl-34550289

ABSTRACT

Colletotrichum is one of the most economically important fungal genera, which affects a wide range of hosts, specifically tropical and subtropical crops. Thus far, there have been several records of mycovirus infection in Colletotrichum spp., primarily by viruses of the Partitiviridae family. There have also been records of infections by mycoviruses of the Chrysoviridae family. Mycoviruses are (+)ssRNA and dsRNA genome viruses, which may or may not be enveloped. To date, no mycovirus with a DNA genome has been isolated from Colletotrichum spp. Typically, mycoviruses cause latent infections, although hypo- and hypervirulence have also been reported in Colletotrichum spp. In addition to its effects on pathogenic behavior, mycovirus infection can lead to important physiological changes, such as altered morphological characteristics, reduced vegetative growth, and suppressed conidia production. Therefore, research on mycoviruses infecting phytopathogenic fungi can help develop alternative methods to chemical control, which can cause irreversible damage to humans and the environment. From an agricultural perspective, mycoviruses can contribute to sustainable agriculture as biological control agents via changes in fungal physiology, ultimately resulting in the total loss of or reduction in the virulence of these pathogens.


Subject(s)
Colletotrichum , Fungal Viruses , RNA Viruses , Fungal Viruses/genetics , Humans , Phylogeny , Spores, Fungal , Virulence
5.
Acta Physiol Scand ; 181(4): 571-7, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15283772

ABSTRACT

Hypertension is a polygenic and multi-factorial disorder that is extremely prevalent in western societies, and thus has received a great deal of attention by the research community. The renin-angiotensin system has a strong impact on the control of blood pressure both in the short- and long-term, making it one of the most extensively studied physiological systems. Nevertheless, despite decades of research, the specific mechanisms implicated in its action on blood pressure and electrolyte balance, as well as its integration with other cardiovascular pathways remains incomplete. The production of transgenic models either over-expressing or knocking-out specific components of the renin-angiotensin system has given us a better understanding of its role in the pathogenesis of hypertension. Moreover, our attention has recently been refocused on local tissue renin-angiotensin systems and their physiological effect on blood pressure and end-organ damage. Herein, we will review studies using genetic manipulation of animals to determine the role of the endocrine and tissue renin-angiotensin system in hypertension. We will also discuss some untraditional approaches to target the renin-angiotensin system in the kidney.


Subject(s)
Disease Models, Animal , Hypertension/physiopathology , Renin-Angiotensin System , Animals , Gene Targeting , Kidney/physiopathology , Mice , Mice, Knockout , Mice, Transgenic
6.
J Nucl Med ; 39(4): 634-9, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9544670

ABSTRACT

UNLABELLED: Many tumors with neuroendocrine characteristics express high amounts of somatostatin receptors that enable in vivo imaging with [(111)In-DTPA-D-Phe1]-octreotide. In this study, we have analyzed the feasibility in detecting and characterizing thymic masses by somatostatin receptor scintigraphy (SRS). METHODS: Eighteen patients (13 women, 5 men, ages 18-78 yr; mean +/- s.d. = 42.1 +/- 17.6 yr) were enrolled in this study. Eleven patients were studied during diagnosis and seven during routine follow-up. In seven patients, myasthenia gravis was the presenting symptom. SRS was performed within 4 wk after CT and/or MRI. Planar and tomographic images were acquired within 24 hr after the injection of approximately 111 MBq of [(111)In-DTPA-D-Phe1]-octreotide. The scintigraphic results were categorized according to the histologic findings. RESULTS: Histology diagnosed 10 mixed epithelial/lymphoid thymomas (8 with prevalent epithelial component), 2 thymic carcinomas, 1 thymic carcinoid, 1 lymphangioma and 4 thymic hyperplasias. Two thymoma were Stage I, 3 were Stage II, 2 were Stage III and 5 were Stage IV, as was the thymic carcinoid. Indium-111-DTPA-D-Phe1-octreotide concentrated in primary and/or metastatic sites of thymic tumors, thereby enabling successful external gamma imaging of sites greater than 1.5 cm in size. Tumor-to-lung (T/L) ratios were as high as 7.6-fold (range 1.7-7.6). Untreated thymomas showed higher T/L (4.34 +/- 1.57) than treated ones (2.68 +/- 1.18). No uptake was detectable in the four patients with benign thymic hyperplasia and the patient with the lymphangioma. CONCLUSION: Indium-111-DTPA-D-Phe1-octreotide is avidly concentrated within thymic tumors, but it is not concentrated by thymic hyperplasia, which allows differential diagnosis. Thus, in patients with myasthenia gravis, SRS may have a role in characterizing thymic masses, thereby overcoming the limits of cross-sectional imaging modalities.


Subject(s)
Octreotide/analogs & derivatives , Pentetic Acid/analogs & derivatives , Radiopharmaceuticals , Thymus Neoplasms/diagnostic imaging , Adolescent , Adult , Aged , Carcinoid Tumor/diagnostic imaging , Carcinoma/diagnostic imaging , Diagnosis, Differential , Female , Humans , Iodine Radioisotopes , Magnetic Resonance Imaging , Male , Middle Aged , Thymoma/diagnosis , Thymoma/diagnostic imaging , Thymus Hyperplasia/diagnosis , Thymus Hyperplasia/diagnostic imaging , Thymus Neoplasms/diagnosis , Tomography, Emission-Computed, Single-Photon , Tomography, X-Ray Computed
7.
Arch Biochem Biophys ; 348(2): 391-402, 1997 Dec 15.
Article in English | MEDLINE | ID: mdl-9434753

ABSTRACT

The species-dependent compartmentation of type I cAMP-dependent protein kinase (PKA I) and its dissociated regulatory subunit (RI) was examined in the heart by biochemical and immunohistochemical means. PKA I and RI were resolved from type II cAMP-dependent protein kinase and its regulatory subunit by DEAE-Sephacel chromatography of the supernatant and Triton X-100 soluble particulate fractions of heart homogenates. The relative amounts of holoenzymes and subunits were determined by cAMP-binding, protein kinase, 8-N3-[32P]cAMP photoaffinity labeling, and Western blot assays. Rat, rabbit, and guinea pig hearts all contained PKA I to varying degrees, but only in the supernatant fractions. Significant amounts of dissociated RI were found in the supernatant fractions, and to a lesser extent the particulate fractions, of these species. In contrast, though no PKA I was detected in the supernatant or particulate fractions of pig and beef heart, half of the cAMP-binding activity in the particulate fraction was attributed to RI. The results suggest that RI may associate with membrane fractions when it is not associated with the PKA catalytic subunit. Immunohistochemical studies of tissue sections from pig, beef, and rat cardiac ventricle using antibodies directed against RI also revealed species-dependent localization of RI. Cardiac myocyte intercalated discs were stained in pig and beef sections with additional sarcolemmal staining in beef sections. Rat ventricle, which contained large amounts of supernatant PKA I, showed nuclear staining. The localization of RI to cardiac myocyte intercalated discs and sarcolemma in certain species suggests a role(s) for this subunit in mediating cAMP-regulated events in these regions.


Subject(s)
Carrier Proteins/analysis , Cyclic AMP-Dependent Protein Kinases/analysis , Intracellular Signaling Peptides and Proteins , Myocardium/enzymology , Animals , Autoradiography , Azides/metabolism , Blotting, Western , Carrier Proteins/isolation & purification , Cattle , Cell Compartmentation , Cell Fractionation , Chromatography, Ion Exchange , Cyclic AMP/analogs & derivatives , Cyclic AMP/metabolism , Cyclic AMP-Dependent Protein Kinase Type II , Cyclic AMP-Dependent Protein Kinases/isolation & purification , Electrophoresis, Polyacrylamide Gel , Fluorescent Antibody Technique , Guinea Pigs , Heart Ventricles , Immunohistochemistry , Myocardium/cytology , Photoaffinity Labels , Protein Binding , Rabbits , Rats , Rats, Sprague-Dawley , Sarcolemma/enzymology , Swine
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