Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 221
Filtrar
1.
J Parasit Dis ; 48(3): 501-513, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39145371

RESUMO

The present study is aimed to investigate potential in vitro anthelmintic efficacy of two phenolic compounds Ferulic acid and Sinapic acid against the parasite H. diminuta. Adult parasites collected from infected rat's intestine (maintained in our laboratory) were treated with 1, 2.5, 5, 10 and 20 mg/mL concentrations of both the compounds in RPMI-1640 media containing 1% Tween 20. Further, one group was treated in Praziquantel as a reference drug and another group of parasites were kept as control. The efficacy was evaluated on the basis of motility and mortality of the parasites. The paralyzed worms were further processed for the morphological and ultrastructural studies and observed through light and scanning electron microscopy. A significant dose-dependent efficacy was found in all treatment and decrease in relative movability value was also recorded in all the concentrations of two compounds treated parasites. The time taken for paralysis in 5 mg/mL of Ferulic acid and 10 mg/mL of Sinapic acid were 1.47 ± 0.04 h and 0.88 ± 0.03 h respectively which is accorded with the standard concentration of Praziquantel. Morphological micrographs revealed pronounced distortion and altered topography of scolex and tegument while histological study showed loss of uniform tegumental integrity with folds and cracks in the treated parasites. Further, extensive alteration in the scolex and irrevocable disruption all over the body surface with loss of trapezoid shape, shrinkage of tegument and sloughing off microtriches were observed in electron microscopic study. The study indicated that both the compounds possess strong activity against H. diminuta and further studies are required to understand their detailed mode of action to exploit them as potential alternative candidates for curing helminthiases.

2.
Parasit Vectors ; 17(1): 342, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148111

RESUMO

BACKGROUND: Artemisinin (ART) analogs, such as dihydroartemisinin, arteether, artemether, and artesunate, all featuring an endoperoxide bridge, have demonstrated efficacy against schistosomiasis. Artemisitene (ATT), which contains an additional α, ß-unsaturated carbonyl structure, has shown enhanced biological activities. This study aims to evaluate the anti-schistosomaiasis japonica activity of ATT and compare it with ART. METHODS: We assessed liver inflammation and fibrosis in mice using hematoxylin and eosin staining and Sirius red staining, respectively. RNA sequencing analyzed transcriptomics in female and male Schistosoma japonicum (S. japonicum) adult worms and mice livers, with cytokine profiling and flow cytometry to study immune responses under ART or ATT treatment. RESULTS: ATT exhibits a marked reduction in female S. japonicum adult worms and egg numbers, damaging the adult worms' surface. It also influences the transcription of genes related to cellular anatomical structures. Notably, ATT treatment resulted in significant reductions in liver granuloma size and collagen area, alongside lowering serum levels of glutamic pyruvic and glutamic oxaloacetic transaminase more effectively than ART. Both ART and ATT markedly decreased neutrophil frequency in the liver and elevated eosinophil counts. However, only ATT treatment significantly reduced the M1/M2 and Th1/Th2 indices, indicating a pronounced shift in immune response profiles. ATT-affected host immunity correlated with the extent of liver fibrosis and the count of single males more strongly than ART. CONCLUSION: ATT, as a novel preventive strategy for schistosomiasis japonica in mice, significantly outperforms ART.


Assuntos
Artemisininas , Fígado , Schistosoma japonicum , Esquistossomose Japônica , Animais , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Esquistossomose Japônica/tratamento farmacológico , Esquistossomose Japônica/prevenção & controle , Esquistossomose Japônica/parasitologia , Camundongos , Schistosoma japonicum/efeitos dos fármacos , Feminino , Masculino , Fígado/parasitologia , Fígado/patologia , Fígado/efeitos dos fármacos , Citocinas/metabolismo , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Modelos Animais de Doenças
3.
J Virol ; 98(9): e0065624, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39136460

RESUMO

The multifunctional tegument protein pUL21 of HSV-2 is phosphorylated in infected cells. We have identified two residues in the unstructured linker region of pUL21, serine 251 and serine 253, as phosphorylation sites. Both phosphorylation sites are absent in HSV-1 pUL21, which likely explains why phosphorylated pUL21 was not detected in cells infected with HSV-1. Cells infected with HSV-2 strain 186 viruses deficient in pUL21 phosphorylation exhibited reductions in both cell-cell spread of virus infection and virus replication. Defects in secondary envelopment of cytoplasmic nucleocapsids were also observed in cells infected with viruses deficient in pUL21 phosphorylation as well as in cells infected with multiple strains of HSV-2 and HSV-1 deleted for pUL21. These results confirm a role for HSV pUL21 in the secondary envelopment of cytoplasmic nucleocapsids and indicate that phosphorylation of HSV-2 pUL21 is required for this activity. Phosphorylation of pUL21 was substantially reduced in cells infected with HSV-2 strain 186 mutants lacking the viral serine/threonine kinase pUL13, indicating a requirement for pUL13 in pUL21 phosphorylation. IMPORTANCE: It is well known that post-translational modification of proteins by phosphorylation can regulate protein function. Here, we determined that phosphorylation of the multifunctional HSV-2 tegument protein pUL21 requires the viral serine/threonine kinase pUL13. In addition, we identified serine residues within HSV-2 pUL21 that can be phosphorylated. Phenotypic analysis of mutant HSV-2 strains with deficiencies in pUL21 phosphorylation revealed reductions in both cell-cell spread of virus infection and virus replication. Deficiencies in pUL21 phosphorylation also compromised the secondary envelopment of cytoplasmic nucleocapsids, a critical final step in the maturation of all herpes virions. Unlike HSV-2 pUL21, phosphorylation of HSV-1 pUL21 was not detected. This fundamental difference between HSV-2 and HSV-1 may underlie our previous observations that the requirements for pUL21 differ between HSV species.


Assuntos
Herpesvirus Humano 2 , Nucleocapsídeo , Replicação Viral , Herpesvirus Humano 2/metabolismo , Herpesvirus Humano 2/genética , Herpesvirus Humano 2/fisiologia , Fosforilação , Animais , Chlorocebus aethiops , Humanos , Células Vero , Nucleocapsídeo/metabolismo , Herpesvirus Humano 1/fisiologia , Herpesvirus Humano 1/metabolismo , Herpesvirus Humano 1/genética , Proteínas Virais/metabolismo , Proteínas Virais/genética , Citoplasma/metabolismo , Citoplasma/virologia , Linhagem Celular , Proteínas Estruturais Virais/metabolismo , Proteínas Estruturais Virais/genética , Montagem de Vírus , Herpes Simples/virologia , Herpes Simples/metabolismo
4.
Dokl Biochem Biophys ; 518(1): 309-312, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38955911

RESUMO

The giant tegument nuclei of the acanthocephalans of the classes Archiacanthocephala and Palaeacanthocephala are fragmented at the final stage of cystacanthus formation in the intermediate host, but remain connected with each other during later life. It can be assumed that the fragments of each giant tegument nucleus are united with each other to form an independent network that ensures the vital activity of the tegument, the volume of which increases many times during the period of intensive growth of the parasite in the definitive host.


Assuntos
Acantocéfalos , Animais , Núcleo Celular
5.
Front Microbiol ; 15: 1431672, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015737

RESUMO

Alphaherpesvirus is a widespread pathogen that causes diverse diseases in humans and animals and can severely damage host health. Alphaherpesvirus particles comprise a DNA core, capsid, tegument and envelope; the tegument is located between the nuclear capsid and envelope. According to biochemical and proteomic analyses of alphaherpesvirus particles, the tegument contains at least 24 viral proteins and plays an important role in the alphaherpesvirus life cycle. This article reviews the important role of tegument proteins and their interactions during the viral life cycle to provide a reference and inspiration for understanding alphaherpesvirus infection pathogenesis and identifying new antiviral strategies.

6.
Vet Parasitol ; 330: 110244, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38964116

RESUMO

Application of 'omics' technology, and advances in in vitro methods for studying the growth of Fasciola hepatica, have highlighted the central role of migrating neoblasts in driving forward development and differentiation towards the adult-like form. Neoblast populations present molecular heterogeneity, morphological variation and changes associated with recruitment of these stem cells into their final tissue locations. However, terminal differentiation towards function, has received much less attention than has been the case for the free-living Platyhelminths. An actively replicating neoblast population, comprising cells with heterochromatic nuclei consistent with regulation of gene expression, has been identified in the parenchyma of juvenile Fasciola gigantica migrating in the liver of experimentally infected mice. In some of these cells, early cytoplasmic differentiation towards myocyte function was noted. Neoblasts have also been identified close to, and incorporated in, the subtegumental zone, the gastrodermis and the excretory ducts. In these locations, progressive morphological differentiation towards terminal function has been described. This includes the appearance of specific progenitors of type-1, type-2 and type-3 tegumental cells, the latter possibly contributing to tegumental spine development. 'Cryptic' surface molecular differentiation is postulated to account for recognition and 'docking' of migrating neoblasts with their final site for terminal differentiation.


Assuntos
Fasciola , Fasciolíase , Fígado , Animais , Camundongos , Fasciolíase/parasitologia , Fasciolíase/veterinária , Fígado/parasitologia , Fasciola/fisiologia , Diferenciação Celular
7.
mBio ; 15(8): e0144524, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-38953638

RESUMO

Neurotropic alphaherpesviruses, including herpes simplex virus type 1 and pseudorabies virus, establish a lifelong presence within the peripheral nervous system of their mammalian hosts. Upon entering cells, two conserved tegument proteins, pUL36 and pUL37, traffic DNA-containing capsids to nuclei. These proteins support long-distance retrograde axonal transport and invasion of the nervous system in vivo. To better understand how pUL36 and pUL37 function, recombinant viral particles carrying BioID2 fused to these proteins were produced to biotinylate cellular proteins in their proximity (<10 nm) during infection. Eighty-six high-confidence host proteins were identified by mass spectrometry and subsequently targeted by CRISPR-Cas9 gene editing to assess their contributions to early infection. Proteins were identified that both supported and antagonized infection in immortalized human epithelial cells. The latter included zyxin, a protein that localizes to focal adhesions and regulates actin cytoskeletal dynamics. Zyxin knockout cells were hyper-permissive to infection and could be rescued with even modest expression of GFP-zyxin. These results provide a resource for studies of the virus-cell interface and identify zyxin as a novel deterrent to alphaherpesvirus infection.IMPORTANCENeuroinvasive alphaherpesviruses are highly prevalent with many members found across mammals [e.g., herpes simplex virus type 1 (HSV-1) in humans and pseudorabies virus in pigs]. HSV-1 causes a range of clinical manifestations from cold sores to blindness and encephalitis. There are no vaccines or curative therapies available for HSV-1. A fundamental feature of these viruses is their establishment of lifelong infection of the nervous system in their respective hosts. This outcome is possible due to a potent neuroinvasive property that is coordinated by two proteins: pUL36 and pUL37. In this study, we explore the cellular protein network in proximity to pUL36 and pUL37 during infection and examine the impact of knocking down the expression of these proteins upon infection.


Assuntos
Biotina , Humanos , Biotina/metabolismo , Zixina/metabolismo , Zixina/genética , Animais , Linhagem Celular , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/fisiologia , Herpesvirus Suídeo 1/genética , Herpesvirus Suídeo 1/fisiologia , Interações Hospedeiro-Patógeno , Alphaherpesvirinae/genética , Alphaherpesvirinae/metabolismo , Sistemas CRISPR-Cas , Células Epiteliais/virologia , Células Epiteliais/metabolismo
8.
Front Immunol ; 15: 1403070, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015575

RESUMO

Background: The cGAS-STING axis-mediated type I interferon pathway is a crucial strategy for host defense against DNA virus infection. Numerous evasion strategies developed by the pseudorabies virus (PRV) counteract host antiviral immunity. To what extent PRV-encoded proteins evade the cGAS-STING signaling pathway is unknown. Methods: Using US2 stably expressing cell lines and US2-deficient PRV model, we revealed that the PRV tegument protein US2 reduces STING protein stability and downregulates STING-mediated antiviral signaling. Results: To promote K48-linked ubiquitination and STING degradation, US2 interacts with the LBD structural domain of STING and recruits the E3 ligase TRIM21. TRIM21 deficiency consistently strengthens the host antiviral immune response brought on by PRV infection. Additionally, US2-deficient PRV is less harmful in mice. Conclusions: Our study implies that PRV US2 inhibits IFN signaling by a new mechanism that selectively targets STING while successfully evading the host antiviral response. As a result, the present study reveals a novel strategy by which PRV evades host defense and offers explanations for why the Bartha-K61 classical vaccine strain failed to offer effective defense against PRV variant strains in China, indicating that US2 may be a key target for developing gene-deficient PRV vaccines.


Assuntos
Herpesvirus Suídeo 1 , Imunidade Inata , Pseudorraiva , Transdução de Sinais , Proteínas do Envelope Viral , Animais , Humanos , Camundongos , Células HEK293 , Herpesvirus Suídeo 1/imunologia , Herpesvirus Suídeo 1/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Evasão da Resposta Imune , Proteínas de Membrana/metabolismo , Proteínas de Membrana/imunologia , Proteínas de Membrana/genética , Nucleotidiltransferases/metabolismo , Nucleotidiltransferases/genética , Nucleotidiltransferases/imunologia , Pseudorraiva/imunologia , Pseudorraiva/virologia , Ribonucleoproteínas/imunologia , Ribonucleoproteínas/metabolismo , Ubiquitinação , Proteínas do Envelope Viral/metabolismo
9.
Virology ; 596: 110115, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38805802

RESUMO

Human cytomegalovirus (HCMV) replication relies on a nucleocapsid coat of the 150 kDa, subfamily-specific tegument phosphoprotein (pp150) to regulate cytoplasmic virion maturation. While recent structural studies revealed pp150-capsid interactions, the role of specific amino-acids involved in these interactions have not been established experimentally. In this study, pp150 and the small capsid protein (SCP), one of pp150's binding partners found atop the major capsid protein (MCP), were subjected to mutational and structural analyses. Mutations to clusters of polar or hydrophobic residues along the pp150-SCP interface abolished viral replication, with no replication detected in mutant virus-infected cells. Notably, a single amino acid mutation (pp150 K255E) at the pp150-MCP interface significantly attenuated viral replication, unlike in pp150-deletion mutants where capsids degraded outside host nuclei. These functionally significant mutations targeting pp150-capsid interactions, particularly the pp150 K255E replication-attenuated mutant, can be explored to overcome the historical challenges of developing effective antivirals and vaccines against HCMV infection.


Assuntos
Proteínas do Capsídeo , Citomegalovirus , Fosfoproteínas , Replicação Viral , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Proteínas do Capsídeo/química , Humanos , Citomegalovirus/genética , Citomegalovirus/fisiologia , Citomegalovirus/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosfoproteínas/química , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/metabolismo , Proteínas da Matriz Viral/química , Ligação Proteica , Mutagênese , Mutação , Linhagem Celular , Modelos Moleculares
11.
Front Immunol, v. 14, 1269336, fev. 2024
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5295

RESUMO

The self-cure of rhesus macaques from a schistosome infection and their subsequent strong immunity to a cercarial challenge should provide novel insights into the way these parasites can be eliminated by immunological attack. High-density arrays comprising overlapping 15-mer peptides from target proteins printed on glass slides can be used to screen sera from host species to determine antibody reactivity at the single epitope level. Careful selection of proteins, based on compositional studies, is crucial to encompass only those exposed on or secreted from the intra-mammalian stages and is intended to focus the analysis solely on targets mediating protection. We report the results of this approach using two pools of sera from hi- and lo-responder macaques undergoing self-cure, to screen arrays comprising tegument, esophageal gland, and gastrodermis proteins. We show that, overall, the target epitopes are the same in both groups, but the intensity of response is twice as strong in the high responders. In addition, apart from Sm25, tegument proteins elicit much weaker responses than those originating in the alimentary tract, as was apparent in IFNγR KO mice. We also highlight the most reactive epitopes in key proteins. Armed with this knowledge, we intend to use multi-epitope constructs in vaccination experiments, which seek to emulate the self-cure process in experimental animals and potentially in humans.

12.
Front Cell Infect Microbiol ; 13: 1286190, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37908761

RESUMO

Background: Tapeworm larvae cause important diseases in humans and domestic animals. During infection, the first larval stage undergoes a metamorphosis where tissues are formed de novo from a population of stem cells called germinative cells. This process is difficult to study for human pathogens, as these larvae are infectious and difficult to obtain in the laboratory. Methods: In this work, we analyzed cell proliferation and differentiation during larval metamorphosis in the model tapeworm Hymenolepis microstoma, by in vivo labelling of proliferating cells with the thymidine analogue 5-ethynyl-2'-deoxyuridine (EdU), tracing their differentiation with a suite of specific molecular markers for different cell types. Results: Proliferating cells are very abundant and fast-cycling during early metamorphosis: the total number of cells duplicates every ten hours, and the length of G2 is only 75 minutes. New tegumental, muscle and nerve cells differentiate from this pool of proliferating germinative cells, and these processes are very fast, as differentiation markers for neurons and muscle cells appear within 24 hours after exiting the cell cycle, and fusion of new cells to the tegumental syncytium can be detected after only 4 hours. Tegumental and muscle cells appear from early stages of metamorphosis (24 to 48 hours post-infection); in contrast, most markers for differentiating neurons appear later, and the detection of synapsin and neuropeptides correlates with scolex retraction. Finally, we identified populations of proliferating cells that express conserved genes associated with neuronal progenitors and precursors, suggesting the existence of tissue-specific lineages among germinative cells. Discussion: These results provide for the first time a comprehensive view of the development of new tissues during tapeworm larval metamorphosis, providing a framework for similar studies in human and veterinary pathogens.


Assuntos
Hymenolepis , Animais , Humanos , Hymenolepis/genética , Metamorfose Biológica/genética , Diferenciação Celular , Músculos , Proliferação de Células , Larva
13.
Viruses ; 15(10)2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37896835

RESUMO

Herpesviruses are enveloped and have an amorphous protein layer surrounding the capsid, which is termed the tegument. Tegument proteins perform critical functions throughout the viral life cycle. This review provides a comprehensive and comparative analysis of the roles of specific tegument proteins in capsid transport and virion morphogenesis of selected, well-studied prototypes of each of the three subfamilies of Herpesviridae i.e., human herpesvirus-1/herpes simplex virus-1 (Alphaherpesvirinae), human herpesvirus-5/cytomegalovirus (Betaherpesvirinae) and human herpesvirus -8/Kaposi's sarcomavirus (Gammaherpesvirinae). Most of the current knowledge is based on alpha herpesviruses, in particular HSV-1. While some tegument proteins are released into the cytoplasm after virus entry, several tegument proteins remain associated with the capsid and are responsible for transport to and docking at the nucleus. After replication and capsid formation, the capsid is enveloped at the nuclear membrane, which is referred to as primary envelopment, followed by de-envelopment and release into the cytoplasm. This requires involvement of at least three tegument proteins. Subsequently, multiple interactions between tegument proteins and capsid proteins, other tegument proteins and glycoproteins are required for assembly of the virus particles and envelopment at the Golgi, with certain tegument proteins acting as the central hub for these interactions. Some redundancy in these interactions ensures appropriate morphogenesis.


Assuntos
Herpesviridae , Herpesvirus Humano 1 , Herpesvirus Humano 8 , Humanos , Proteínas do Capsídeo/metabolismo , Capsídeo/metabolismo , Montagem de Vírus , Herpesviridae/metabolismo , Herpesvirus Humano 1/metabolismo , Herpesvirus Humano 8/metabolismo , Morfogênese , Vírion/metabolismo , Proteínas Estruturais Virais/metabolismo
14.
Biosci Rep ; 43(11)2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-37881894

RESUMO

The need to minimise the impact of phytosanitary treatments for disease control boosted researchers to implement techniques with less environmental impact. The development of technologies using molecular mechanisms based on the modulation of metabolism by short dsRNA sequences appears promising. The intrinsic fragility of polynucleotides and the high cost of these techniques can be circumvented by nanocarriers that protect the bioactive molecule enabling high efficiency delivery to the leaf surface and extending its half-life. In this work, a specific protocol was developed aiming to assess the best methodological conditions for the synthesis of low-size chitosan nanoparticles (NPs) to be loaded with nucleotides. In particular, NPs have been functionalised with partially purified Green Fluorescent Protein dsRNAs (GFP dsRNA) and their size, surface charge and nucleotide retention capacity were analysed. Final NPs were also stained with FITC and sprayed on Nicotiana benthamiana leaves to assess, by confocal microscopy, both a distribution protocol and the fate of NPs up to 6 days after application. Finally, to confirm the ability of NPs to increase the efficacy of dsRNA interference, specific tests were performed: by means of GFP dsRNA-functionalised NPs, the nucleotide permanence during time was assessed both in vitro on detached wild-type N. benthamiana leaves and in planta; lastly, the inhibition of Botrytis cinerea on single leaves was also evaluated, using a specific fungal sequence (Bc dsRNA) as the NPs' functionalising agent. The encouraging results obtained are promising in the perspective of long-lasting application of innovative treatments based on gene silencing.


Assuntos
Quitosana , Nanopartículas , RNA de Cadeia Dupla/genética , Interferência de RNA , Proteção de Cultivos , Nucleotídeos
15.
Polymers (Basel) ; 15(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37571057

RESUMO

The growing demand for cellulosic pulp presents an opportunity to explore alternatives to this material, focusing on utilizing agro-industrial residues. Mango's tegument is a rich source of cellulose, making it a valuable raw material for manufacturing single-use articles or blends with biopolymers. In this sense, employing conventional alkaline and acid chemical treatments, the mango's tegument was treated to obtain cellulosic pulp. The teguments were subjected to treatment with alkaline solutions (2% and 4% NaOH w/v) at 80 °C for 1 or 2 h or with an acetic acid solution (1:1 or 1:2 CH3COOH:H2O2) at 60-70 °C for 1 or 2 h. After treatment, an evaluation was conducted to assess the yield, color, chemical analysis, and structural, thermal, and morphological properties. The alkali treatments produced cellulosic pulps with a light color with 37-42% yield and reduced hemicellulose content. The acid treatments produced orange-brown cellulosic pulp with 47-48% yield and higher hemicellulose content. The acid pulps were thermally more stable (maximum decomposition at 348-357 °C) than the alkali pulps (maximum decomposition at 316-321 °C). The crystallinity index demonstrated that both treatments increased the crystallinity of the cellulose pulps compared with the untreated tegument. The thermal stability of cellulosic pulp at the processing temperatures of disposable tableware (50-120 °C) revealed that plates, bowls, trays, and cups could be produced. Another potential application is as a component of blends with biopolymers to make straws or rigid food packaging (trays) with reinforced structures.

16.
Parasitol Res ; 122(10): 2287-2299, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37507540

RESUMO

Tapeworm infections cause insidious and irreversible effects in the infected individuals and some of them have already shown resistance to available drugs. A search for alternative treatment is urgently required. Phenolic compounds are amongst the most researched natural substances for their medicinal use. The present study aims to determine anthelmintic efficacy of two polyphenols Gallic acid and Catechin against the zoonotic rat tapeworm Hymenolepis diminuta. Both compounds are potent anti-oxidants and play major roles in combating pathogens, while their anthelmintic property according to our knowledge is yet to be explored. The parasite model H. diminuta was procured from intestine of infected rats raised in our laboratory. Two sets of parasites were treated in vitro with 5, 10, 20 and 40 mg/ml concentrations of each Gallic Acid and Catechin separately, another set of parasites were treated with standard dose of Praziquantel in RPMI 1640, while still another set of worms were kept in RPMI 1640 at 37 ± 10C with 1% Dimethyl sulfoxide as control. Motility and structural alterations were the parameters assessed for anthelmintic efficacy of the compounds. After paralysis the worms were processed for morphological, histological, and ultrastructural study and observed under light and electron microscope. Dose-dependent efficacy was observed in both compounds. Shrinkage of suckers, deformed proglottids and architectural alteration of the tegument were observed throughout the body of treated parasites compared to control. Although in terms of time taken for paralysis and mortality Gallic acid was more effective than Catechin, the degree of morphological aberrations caused were almost similar, except histological alteration was more in Catechin treated worms than in Gallic acid. Nevertheless, both Gallic acid and Catechin are suggested to possess anthelmintic efficacy besides other health benefits but extended studies are required to compare their efficacy.


Assuntos
Anti-Helmínticos , Catequina , Himenolepíase , Hymenolepis diminuta , Hymenolepis , Parasitos , Ratos , Animais , Catequina/farmacologia , Catequina/uso terapêutico , Ácido Gálico/farmacologia , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Himenolepíase/parasitologia
17.
J Infect Dis ; 228(11): 1491-1495, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37340664

RESUMO

Developing a vaccine to prevent congenital cytomegalovirus (CMV) infection and newborn disability requires an understanding of infection incidence. In a prospective cohort study of 363 adolescent girls (NCT01691820), CMV serostatus, primary infection, and secondary infection were determined in blood and urine samples collected at enrollment and every 4 months for 3 years. Baseline CMV seroprevalence was 58%. Primary infection occurred in 14.8% of seronegative girls. Among seropositive girls, 5.9% had ≥4-fold increase in anti-CMV antibody, and 23.9% shed CMV DNA in urine. Our findings provide insights on infection epidemiology and highlight the need for more standardized markers of secondary infection.


Cytomegalovirus (CMV) can be passed from a woman to her unborn baby during pregnancy, which can result in disabilities in the baby. This can happen after a first infection with the virus during pregnancy, after a subsequent infection with a different strain ("reinfection"), or after "reactivation", which means that a virus present from a previous infection becomes active again. Vaccinating adolescent girls against CMV may be a future strategy to help prevent CMV infection during pregnancy. To provide information to design trials evaluating a CMV vaccine, it is important to know how common primary/secondary CMV infection is in adolescent girls and if this can be measured with available tools. We followed adolescent girls living in Finland, Mexico or the United States for three years. At study start, 58% of these girls showed evidence of previous CMV infection. During the three-year follow-up, a first CMV infection occurred in 15% of girls, and reinfection or reactivation in 6% to 24% of girls (depending on the method used). The obtained estimates of CMV infection rates in adolescent girls provide valuable information for future studies to evaluate CMV vaccines, but standardized markers for secondary infection are needed.


Assuntos
Coinfecção , Infecções por Citomegalovirus , Adolescente , Feminino , Humanos , Anticorpos Antivirais , Citomegalovirus , Incidência , Estudos Prospectivos , Estudos Soroepidemiológicos
18.
Tumour Virus Res ; 15: 200260, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37169175

RESUMO

The tegument is the structure between the envelope and nucleocapsid of herpesvirus particles. Viral (and cellular) proteins accumulate to create the layers of the tegument. Some Epstein-Barr virus (EBV) tegument proteins are conserved widely in Herpesviridae, but others are shared only by members of the gamma-herpesvirus subfamily. As the interface to envelope and nucleocapsid, the tegument functions in virion morphogenesis and budding of the nucleocapsid during progeny production. When a virus particle enters a cell, enzymes such as kinase and deubiquitinase, and transcriptional activators are released from the virion to promote virus infection. Moreover, some EBV tegument proteins are involved in oncogenesis. Here, we summarize the roles of EBV tegument proteins, in comparison to those of other herpesviruses.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesviridae , Humanos , Herpesvirus Humano 4 , Montagem de Vírus , Carcinogênese , Transformação Celular Neoplásica
19.
Front Microbiol ; 14: 1171770, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37234529

RESUMO

Bovine herpesvirus 4 (BoHV-4) is a Gammaherpesvirus belonging to the Rhadinovirus genus. The bovine is BoHV-4's natural host, and the African buffalo is BoHV-4's natural reservoir. In any case, BoHV-4 infection is not associated with a specific disease. Genome structure and genes are well-conserved in Gammaherpesvirus, and the orf 45 gene and its product, ORF45, are one of those. BoHV-4 ORF45 has been suggested to be a tegument protein; however, its structure and function have not yet been experimentally characterized. The present study shows that BoHV-4 ORF45, despite its poor homology with other characterized Rhadinovirus ORF45s, is structurally related to Kaposi's sarcoma-associated herpesvirus (KSHV), is a phosphoprotein, and localizes in the host cell nuclei. Through the generation of an ORF45-null mutant BoHV-4 and its pararevertant, it was possible to demonstrate that ORF45 is essential for BoHV-4 lytic replication and is associated with the viral particles, as for the other characterized Rhadinovirus ORF45s. Finally, the impact of BoHV-4 ORF45 on cellular transcriptome was investigated, an aspect poorly explored or not at all for other Gammaherpesvirus. Many cellular transcriptional pathways were found to be altered, mainly those involving p90 ribosomal S6 kinase (RSK) and signal-regulated kinase (ERK) complex (RSK/ERK). It was concluded that BoHV-4 ORF45 has similar characteristics to those of KSHV ORF45, and its unique and incisive impact on the cell transcriptome paves the way for further investigations.

20.
Curr Opin Virol ; 60: 101328, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37031486

RESUMO

Cytomegaloviruses (CMVs) are typically disseminated by cell-to-cell transfer, which requires reprogramming of cellular signaling pathways and restructuring of the cell architecture. Viral particles not only transfer genetic information between cells, but also tegument proteins that enable the virus to counteract cellular defense mechanisms immediately upon entering cells. The UL25 gene family of CMVs encodes such tegument proteins and also gives rise to related nonstructural proteins expressed early in infection. Herein, we report on the functions attributed to UL25 family members of several ß-herpesviruses, particularly to the M25 proteins of mouse CMV that were found to interfere with the antiviral role of the p53 tumor suppressor protein and to mediate cytoskeleton rearrangement of infected cells.


Assuntos
Infecções por Citomegalovirus , Camundongos , Animais , Citomegalovirus/genética , Citomegalovirus/metabolismo , Comunicação Celular
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA