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1.
Cureus ; 16(1): e52026, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38344550

RESUMO

INTRODUCTION: In the majority of orthodontic premolar extraction cases, the canine retraction phase is the most laborious procedure. This randomized clinical trial aimed to assess the effect of single versus repeated micro-osteoperforations (MOPs) during orthodontic canine retraction. METHODS: In this split-mouth study, two equal groups of 18 patients who required maxillary first premolar extractions and fixed orthodontic therapy were randomly assigned (n=9). In Group I, MOPs were only performed once on one site before retraction, whereas in Group II, MOPs were performed on one site repeatedly once a month for four months. In both groups, the contralateral control sites received no MOPs. The canines were retracted using mini-screws and closed-coil nickel-titanium springs. Using the patients' 3D models, the primary outcome measure at four months was the amount of orthodontic canine distal movement. The amount of anchorage loss (AL), degree of molar rotation (MR) and canine rotation (CR), and degree of canine tipping (CT) were measured as the secondary outcomes. The comparison of mean changes in the primary and secondary outcomes between the groups was done using the independent sample t-test (p<0.05). RESULTS: The rate of canine retraction, degree of CT, and rotation were not significantly different between the two groups (p>0.05). Additionally, there were no statistically significant variations in the maxillary first MR and the degree of AL (p>0.05). CONCLUSIONS: When maxillary canine retraction was performed with a single and repeated regimen of MOPs, comparable levels of distal CR and tipping were observed, along with an identical minimal degree of MR and AL.

2.
Transbound Emerg Dis ; 69(2): 849-863, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33955204

RESUMO

Newcastle disease (ND), caused by avian orthoavulavirus type-1 (NDV), is endemic in poultry in many regions of the world and causes continuing outbreaks in poultry populations. In the Middle East, genotype XXI, used to be present in poultry in Egypt but has been replaced by genotype VII. We investigated whether virus evolution contributed to superseding and focussed on the antigenic sites within the hemagglutinin-neuraminidase (HN) spike protein. Full-length sequences of an NDV genotype VII isolate currently circulating in Egypt was compared to a genotype XXI isolate that was present as co-infection with vaccine-type viruses (II) in a historical virus isolated in 2011. Amino acid differences in the HN glycoprotein for both XXI and VII viruses amounted to 11.7% and 11.9%, respectively, compared to the La Sota vaccine type. However, mutations within the globular head (aa 126-570), bearing relevant antigenic sites, were underrepresented (a divergence of 8.8% and 8.1% compared to 22.4% and 25.6% within the protein domains encompassing cytoplasmic tail, transmembrane part and stalk regions (aa 1-125) for genotypes XXI and VII, respectively). Nevertheless, reaction patterns of HN-specific monoclonal antibodies inhibiting receptor binding revealed differences between vaccine-type viruses and genotype XXI and VII viruses for epitopes located in the head domain. Accordingly, compared to Egyptian vaccine-type isolates and the La Sota vaccine reference strain, single aa substitutions in 6 of 10 described neutralizing epitopes of HN were found. However, the same alterations in neutralization sensitive epitopes were present in old genotype XXI as well as in newly emerged genotype VII isolates. In addition, isolates were indistinguishable by polyclonal chicken sera raised against different genotypes including vaccine viruses. These findings suggest that factors other than antigenic differences within the HN protein account for facilitating the spread of genotype VII versus genotype XXI viruses in Egypt.


Assuntos
Doença de Newcastle , Vírus da Doença de Newcastle , Animais , Deriva e Deslocamento Antigênicos , Galinhas , Egito/epidemiologia , Genômica , Genótipo , Doença de Newcastle/epidemiologia , Doença de Newcastle/prevenção & controle , Filogenia
4.
Future Med Chem ; 13(7): 625-641, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33624540

RESUMO

New hexahydropyrimido[1,2-a]azepine derivatives bearing functionalized aryl and heterocyclic moieties were synthesized as anti-inflammatory agents with better safety profiles. All synthesized compounds were assessed in vitro for their COX-1 and COX-2 inhibition activities. The most selective compounds, 2f, 5 and 6, were further evaluated for their in vivo anti-inflammatory activity and PGE2 inhibitory activity. To rationalize their selectivity, molecular docking within COX-1 and COX-2 binding sites was performed. Their physicochemical properties and drug-like nature profile were also calculated. The good activity and selectivity of compounds 2f, 5 and 6 were rationalized using a molecular docking study and supported by in vivo studies. These promising findings are encouraging for performing future investigations of these derivatives.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Azepinas/farmacologia , Edema/tratamento farmacológico , Pirimidinas/farmacologia , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Azepinas/síntese química , Azepinas/química , Carragenina , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Edema/induzido quimicamente , Edema/metabolismo , Simulação de Acoplamento Molecular , Pirimidinas/síntese química , Pirimidinas/química , Ratos , Relação Estrutura-Atividade
5.
Vet Sci ; 7(4)2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33348570

RESUMO

Infectious bronchitis virus (IBV) is a highly evolving avian pathogen that has increasingly imposed a negative impact on poultry industry worldwide. In the last 20 years, IBV has been continuously circulating among chicken flocks in Egypt causing huge economic losses to poultry production. Multiple IBV genotypes, namely, GI-1, GI-13, GI-16, and GI-23 have been reported in Egypt possessing different genetic and pathogenic features. Different vaccine programs are being used to control the spread of the disease in Egypt. However, the virus continues to spread and evolve where multiple IBV variants and several recombination evidence have been described. In this review, we highlight the current knowledge concerning IBV circulation, genesis, and vaccination strategies in Egypt. In addition, we analyze representative Egyptian IBV strains from an evolutionary perspective based on available data of their S1 gene. We also provide insight into the importance of surveillance programs and share our perspectives for better control of IBV circulating in Egypt.

6.
Infect Genet Evol ; 84: 104375, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32454245

RESUMO

Highly pathogenic (HP) H5N1, clade 2.2.1, and low pathogenic avian influenza (LPAI) H9N2 viruses, G1-B lineage, are endemic in poultry in Egypt and have co-circulated for almost a decade. Surprisingly, no inter-subtypic reassortment events have been reported from the field during that time. After the introduction of HPAIV H5N8, clade 2.3.4.4b, in Egyptian poultry in 2016, suddenly HP H5N2 reassortants with H9N2 viruses emerged. The current analyses focussed on studying 32 duck flocks, 4 broiler chicken flocks, and 1 turkey flock, suffering from respiratory manifestations with moderate to high mortality reared in two Egyptian governorates during 2019. Real-time RT-PCR substantiated the presence of HP H5N8 in 21 of the 37 investigated flocks with mixed infection of H9N2 in two of them. HP H5N1 was not detected. Full hemagglutinin (HA) sequencing of 10 samples with full-genome sequencing of three of them revealed presence of a single genotype. Very few substituting mutations in the HA protein were detected versus previous Egyptian HA sequences of that clade. Interestingly, amino acid substitutions in the Matrix (M2) and the Neuraminidase (NA) proteins associated with conferring both Amantadine and Oseltamivir resistance were present. Systematic reassortment analysis of all publicly available Egyptian whole genome sequences of HP H5N8 (n = 23), reassortant HP H5N2 (n = 2) and LP H9N2 (n = 53) viruses revealed presence of at least seven different genotypes of HPAI H5Nx viruses of clade 2.3.4.4b in Egypt since 2016. For H9N2 viruses, at least three genotypes were distinguishable. Heat mapping and tanglegram analyses suggested that several internal gene segments in both HP H5Nx and H9N2 viruses originated from avian influenza viruses circulating in wild bird species in Egypt. Based on the limited set of whole genome sequences available, annual replacement patterns of HP H5Nx genotypes emerged and suggested selective advantages of certain genotypes since 2016.


Assuntos
Vírus da Influenza A Subtipo H5N2/genética , Vírus da Influenza A Subtipo H5N8/genética , Influenza Aviária/virologia , Filogenia , Animais , Egito/epidemiologia , Genoma Viral , Genótipo , Vírus da Influenza A Subtipo H5N2/patogenicidade , Vírus da Influenza A Subtipo H5N8/patogenicidade , Influenza Aviária/epidemiologia , Influenza Aviária/mortalidade , Mortalidade , Aves Domésticas/virologia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/mortalidade , Doenças das Aves Domésticas/virologia
7.
Emerg Infect Dis ; 26(1): 129-133, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31855539

RESUMO

We detected a novel reassortant highly pathogenic avian influenza A(H5N2) virus in 3 poultry farms in Egypt. The virus carried genome segments of a pigeon H9N2 influenza virus detected in 2014, a nucleoprotein segment of contemporary chicken H9N2 viruses from Egypt, and hemagglutinin derived from the 2.3.4.4b H5N8 virus clade.


Assuntos
Galinhas/virologia , Vírus da Influenza A Subtipo H5N2 , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Vírus Reordenados , Animais , Patos/virologia , Egito/epidemiologia , Vírus da Influenza A Subtipo H5N2/genética , Vírus da Influenza A Subtipo H5N2/patogenicidade , Influenza Aviária/epidemiologia , Filogenia , Doenças das Aves Domésticas/epidemiologia , Vírus Reordenados/genética
8.
Vet Res ; 50(1): 12, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30744668

RESUMO

Infectious bronchitis virus (IBV) causes a major disease problem for the poultry industry worldwide. The currently used live-attenuated vaccines have the tendency to mutate and/or recombine with circulating field strains resulting in the emergence of vaccine-derived variant viruses. In order to circumvent these issues, and to develop a vaccine that is more relevant to Egypt and its neighboring countries, a recombinant avirulent Newcastle disease virus (rNDV) strain LaSota was constructed to express the codon-optimized S glycoprotein of the Egyptian IBV variant strain IBV/Ck/EG/CU/4/2014 belonging to GI-23 lineage, that is prevalent in Egypt and in the Middle East. A wild type and two modified versions of the IBV S protein were expressed individually by rNDV. A high level of S protein expression was detected in vitro by Western blot and immunofluorescence analyses. All rNDV-vectored IBV vaccine candidates were genetically stable, slightly attenuated and showed growth patterns comparable to that of parental rLaSota virus. Single-dose vaccination of 1-day-old SPF White Leghorn chicks with the rNDVs expressing IBV S protein provided significant protection against clinical disease after IBV challenge but did not show reduction in tracheal viral shedding. Single-dose vaccination also provided complete protection against virulent NDV challenge. However, prime-boost vaccination using rNDV expressing the wild type IBV S protein provided better protection, after IBV challenge, against clinical signs and significantly reduced tracheal viral shedding. These results indicate that the NDV-vectored IBV vaccines are promising bivalent vaccine candidates to control both infectious bronchitis and Newcastle disease in Egypt.


Assuntos
Galinhas , Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa/imunologia , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Animais , Linhagem Celular , Infecções por Coronavirus/prevenção & controle , Egito , Vetores Genéticos/imunologia , Vírus da Bronquite Infecciosa/genética , Vírus da Doença de Newcastle/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
9.
Herz ; 43(7): 633-641, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28835981

RESUMO

BACKGROUND: Pulmonary atresia with intact ventricular septum (PA-IVS) is an uncommon disorder with significant morphological heterogeneity. The use of percutaneous radiofrequency (RF)-assisted perforation of the atretic valve and subsequent balloon dilation provides a relatively easy but expensive procedure that is expected to establish ante-grade flow through the pulmonary valve in most patients. OBJECTIVES: The aim of the study was to attempt a cost reduction by using catheters and wires readily available in our catheter laboratory. METHODS: A total of 50 patients presenting with PA-IVS to Cairo University Children's Hospital (CUCH) were taken to the catheterization laboratory for radiofrequency perforation using the Baylis RFP-100 generator (Baylis Medical, Montréal, Canada) or the stiff end of a coronary wire. A hybrid approach was used in selected cases. RESULTS: The overall success rate for valve perforation was 92% (46 cases), 80% of which had successful primary perforation (40 cases). Success correlated with both tricuspid valve (TV) annulus and pulmonary valve (PV) annulus Z-scores, with P values of 0.2 and 0.5, respectively. CONCLUSION: The management of PA-IVS is complex. This is a disease that necessitates a dedicated team and working collaboration between the cardiologists and cardiac surgeons. Cost limitation is essential in developing countries and innovative ideas to reduce costs are essential, especially if comparable success can be expected.


Assuntos
Ablação por Cateter , Cardiopatias Congênitas , Atresia Pulmonar , Egito , Cardiopatias Congênitas/terapia , Humanos , Recém-Nascido , Atresia Pulmonar/terapia , Estudos Retrospectivos
10.
Infect Genet Evol ; 53: 7-14, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28495648

RESUMO

Avian infectious bronchitis virus (IBV) is highly prevalent in chicken populations and is responsible for severe economic losses to poultry industry worldwide. In this study, we report the complete genome sequences of two IBV field strains, CU/1/2014 and CU/4/2014, isolated from vaccinated chickens in Egypt in 2014. The genome lengths of the strains CU/1/2014 and CU/4/2014 were 27,615 and 27,637 nucleotides, respectively. Both strains have a common genome organization in the order of 5'-UTR-1a-1b-S-3a-3b-E-M-4b-4c-5a-5b-N-6b-UTR-poly(A) tail-3'. Interestingly, strain CU/1/2014 showed a novel 15-nt deletion in the 4b-4c gene junction region. Phylogenetic analysis of the full S1 genes showed that the strains CU/1/2014 and CU/4/2014 belonged to IBV genotypes GI-1 lineage and GI-23 lineage, respectively. The genome of strain CU/1/2014 is closely related to vaccine strain H120 but showed genome-wide point mutations that lead to 27, 14, 11, 1, 1, 2, 2, and 2 amino acid differences between the two strains in 1a, 1b, S, 3a, M, 4b, 4c, and N proteins, respectively, suggesting that strain CU/1/2014 is probably a revertant of the vaccine strain H120 and evolved by accumulation of point mutations. Recombination analysis of strain CU/4/2014 showed evidence for recombination from at least three different IBV strains, namely, the Italian strain 90254/2005 (QX-like strain), 4/91, and H120. These results indicate the continuing evolution of IBV field strains by genetic drift and by genetic recombination leading to outbreaks in the vaccinated chicken populations in Egypt.


Assuntos
Infecções por Coronavirus/veterinária , Genoma Viral , Vírus da Bronquite Infecciosa/genética , Doenças das Aves Domésticas/epidemiologia , RNA Viral/genética , Vírus Reordenados/genética , Recombinação Genética , Animais , Galinhas , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Egito/epidemiologia , Deriva Genética , Tamanho do Genoma , Genótipo , Vírus da Bronquite Infecciosa/classificação , Vírus da Bronquite Infecciosa/isolamento & purificação , Fases de Leitura Aberta , Filogenia , Doenças das Aves Domésticas/transmissão , Doenças das Aves Domésticas/virologia , Prevalência , Vírus Reordenados/classificação , Vírus Reordenados/isolamento & purificação , Sequenciamento Completo do Genoma
11.
Future Med Chem ; 9(6): 553-578, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28394629

RESUMO

AIM: The discovery of new generation of selective COX-2 inhibitors with potential analgesic and anti-inflammatory activity and minimal side effects is a major interest. MATERIALS & METHODS: Novel imidazole and imidazo[1,5-a]quinazoline derivatives were prepared and evaluated for their analgesic and anti-inflammatory activities. COX-1/COX-2 isozyme selectivity testing and molecular docking were performed. Key physicochemical parameters were calculated. RESULTS: All tested compounds exhibited significant activities compared with indomethacin as reference drug. Pharmacological evaluation showed that compounds 3c and 14c possess promising analgesic activity, pronouncing anti-inflammatory effect and reasonable COX-2 selectivity. Molecular docking attributed their good activity to their hydrogen bonding interaction with key amino acids in COX isozymes Arg120, Tyr355 and Ser530. Most compounds obeyed 'Lipinski's rule of five' and possess promising pharmacokinetic properties.


Assuntos
Analgésicos/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Ciclo-Oxigenase 2/metabolismo , Simulação de Acoplamento Molecular , Dor/tratamento farmacológico , Analgésicos/síntese química , Analgésicos/química , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Benzoquinonas , Inibidores de Ciclo-Oxigenase 2/síntese química , Inibidores de Ciclo-Oxigenase 2/química , Humanos , Imidazóis/síntese química , Imidazóis/química , Imidazóis/farmacologia , Camundongos , Estrutura Molecular , Dor/induzido quimicamente , Relação Estrutura-Atividade
12.
J Adv Res ; 7(6): 923-929, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27699067

RESUMO

The interference is the most important problem in LTE or LTE-Advanced networks. In this paper, the interference was investigated in terms of the downlink signal to interference and noise ratio (SINR). In order to compare the different frequency reuse methods that were developed to enhance the SINR, it would be helpful to have a generalized expression to study the performance of the different methods. Therefore, this paper introduces general expressions for the SINR in homogeneous and in heterogeneous networks. In homogeneous networks, the expression was applied for the most common types of frequency reuse techniques: soft frequency reuse (SFR) and fractional frequency reuse (FFR). The expression was examined by comparing it with previously developed ones in the literature and the comparison showed that the expression is valid for any type of frequency reuse scheme and any network topology. Furthermore, the expression was extended to include the heterogeneous network; the expression includes the problem of co-tier and cross-tier interference in heterogeneous networks (HetNet) and it was examined by the same method of the homogeneous one.

13.
J Adv Res ; 7(1): 89-94, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26843974

RESUMO

Dynamic power estimation is essential in designing VLSI circuits where many parameters are involved but the only circuit parameter that is related to the circuit operation is the nodes' toggle rate. This paper discusses a deterministic and fast method to estimate the dynamic power consumption for CMOS combinational logic circuits using gate-level descriptions based on the Logic Pictures concept to obtain the circuit nodes' toggle rate. The delay model for the logic gates is the real-delay model. To validate the results, the method is applied to several circuits and compared against exhaustive, as well as Monte Carlo, simulations. The proposed technique was shown to save up to 96% processing time compared to exhaustive simulation.

14.
J Adv Res ; 6(6): 949-55, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26644933

RESUMO

This paper investigates the problem of inter-cell interference (ICI) in Long Term Evolution (LTE) mobile systems, which is one of the main problems that causes loss of packets between the base station and the mobile station. Recently, different frequency reuse methods, such as soft and fractional frequency reuse, have been introduced in order to mitigate this type of interference. In this paper, minimizing the packet loss between the base station and the mobile station is the main concern. Soft Frequency Reuse (SFR), which is the most popular frequency reuse method, is examined and the amount of packet loss is measured. In order to reduce packet loss, a new hybrid frequency reuse method is implemented. In this method, each cell occupies the same bandwidth of the SFR, but the total system bandwidth is greater than in SFR. This will provide the new method with a lot of new sub-carriers from the neighboring cells to reduce the ICI which represents a big problem in many applications and causes a lot of packets loss. It is found that the new hybrid frequency reuse method has noticeable improvement in the amount of packet loss compared to SFR method in the different frequency bands. Traffic congestion management in Intelligent Transportation system (ITS) is one of the important applications that is affected by the packet loss due to the large amount of traffic that is exchanged between the base station and the mobile node. Therefore, it is used as a studied application for the proposed frequency reuse method and the improvement in the amount of packet loss reached 49.4% in some frequency bands using the new hybrid frequency reuse method.

15.
Molecules ; 17(10): 12262-75, 2012 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-23079497

RESUMO

A series of 2,4-diaryl-5(4H)-imidazolones were prepared and evaluated for their anti-inflammatory activities. Some selected 2,4-diaryl-5(4H)-imidazolones exhibited excellent anti-inflammatory activity in the carrageenan-induced rat paw edema model. Structure Activity Relationships within the series were studied. The substitution at the N-sulfonamide moiety by a small hydrophilic acetyl group resulted in compounds with superior in vivo anti-inflammatory properties. As expected from their COX-2 selectivity, most of the active compounds lacked gastrointestinal toxicity in vivo in rats after a 3-day treatment of 25 mg/kg/day.


Assuntos
Anti-Inflamatórios/síntese química , Anti-Inflamatórios/farmacologia , Desenho de Fármacos , Imidazóis/síntese química , Imidazóis/farmacologia , Animais , Anti-Inflamatórios/química , Sítios de Ligação , Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/síntese química , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Edema/induzido quimicamente , Edema/tratamento farmacológico , Imidazóis/química , Masculino , Simulação de Acoplamento Molecular , Ligação Proteica , Ratos , Relação Estrutura-Atividade
16.
Arch Pharm Res ; 31(5): 562-8, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18481009

RESUMO

Three novel series of 2-(substituted phenyl)-4-(substituted arylidene)-imidazolone-5-(4H)-ones were derived from the corresponding oxazolones by condensation with different arylamines. Eleven of the synthesized compounds were selected and evaluated for their effect on carrageenan-induced rat paw edema. Compound 4b had the same efficacy as the reference standard (indomethacin), and compounds 3b, 3c, 4a, 4d and 9a showed good to excellent activities, with other compounds only weakly active. The potent compounds were evaluated for their inhibitory activities against COX-2-catalyzed PGE(2) production, with 4a, 4b and 3c showing strong inhibitory activity.


Assuntos
Inibidores de Ciclo-Oxigenase 2/síntese química , Imidazóis/síntese química , Animais , Carragenina , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Dinoprostona/sangue , Edema/induzido quimicamente , Edema/tratamento farmacológico , Feminino , Humanos , Imidazóis/química , Imidazóis/farmacologia , Técnicas In Vitro , Masculino , Ratos
17.
APMIS ; 109(5): 376-82, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11478685

RESUMO

In this work, the changes in expression of the adhesion molecules ICAM-1/LFA-1 on inflammatory cells of the liver were studied by immunohistochemistry. Mice sensitized with SEA and infected with S. mansoni and S. mansoni-infected controls were examined from day 35 to day 56 postinfection. A significant upregulation of ICAM-1 and LFA-1 in both the SEA group and the infected control group started shortly after egg deposition at day 35 and persisted up to day 56 p.i. Notably, both ICAM-1 and LFA-1 expression peaks were shifted earlier to day 38 p.i. in the SEA group compared to day 40 in the infected control group. The distribution of ICAM-1 and LFA-1 in both groups was comparable. At the early phase of infection before granuloma formation, both ICAM-1 and LFA-1 were detected along the sinusoidal wall of small blood vessels. At the acute cellular granuloma phase, they were homogeneously distributed all over the inflammatory cells, while at the chronic fibrocellular stage a non-homogeneous staining of granuloma cells at the periphery of the granuloma was apparent. The present data suggest that adhesion molecules play a role in the initiation and maintenance of granuloma formation. Thus, the granulomatous hyporesponsiveness induced by sensitization with SEA was associated with reduced expression of adhesion molecules.


Assuntos
Antígenos de Helmintos/imunologia , Granuloma/patologia , Molécula 1 de Adesão Intercelular/análise , Antígeno-1 Associado à Função Linfocitária/análise , Schistosoma mansoni/imunologia , Esquistossomose mansoni/patologia , Animais , Feminino , Granuloma/parasitologia , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Óvulo/imunologia , Fatores de Tempo
18.
Int J Immunopharmacol ; 22(11): 979-88, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11090706

RESUMO

This study was undertaken to evaluate the effect of recombinant Schistosoma mansoni-26 Glutathione S-transferase (rSm 26 GST) or soluble egg antigen (SEA) alone and in addition to praziquantel (PZQ) on the state of resistance to S. mansoni reinfection. The associated changes in the immune responses were evaluated. The experimental group of mice were injected intravenously before S. mansoni infection (80 cercariae/mouse) either with rSm26 GST (1 microgx4) or SEA (10 microgx4) in addition to PZQ (2x500 mg/kg) administered 6 weeks post-infection. Seven control groups were used, three of them were the infected (80 cercariae/mouse), the challenged (240 cercariae/mouse) and the infected challenged controls (80+240 cercariae/mouse). The rest of the four groups were the treated controls receiving: the GST-Lyzate, rSmGST, SEA and PZQ in the same doses and at the same timings. Challenge infection was conducted for all the groups 8 weeks post-infection. Animals were sacrificed 3 weeks post-challenge. After sacrifice animals were perfused and percentage resistance to reinfection was calculated. Immune responses were assessed by the measurement of hepatic granuloma diameter, intralesional T-cell phenotypes and serum immunoglobulin isotypes. The highest percentage of resistance to reinfection was observed in rGST-treated group while the lowest percentage of resistance was detected in PZQ-treated group. Whereas in mice receiving combined rGST or SEA and PZQ, percentage resistance to reinfection was significantly higher than that in PZQ treated mice. The remarkable reduction in granuloma diameter in rGST-treated group with or without PZQ was associated with decrease in the intralesional L(3)T(4)(+) and increase in Lyt(2)(+) T-cell phenotypes. However, no special relationship was observed between the percentage of resistance and the changes in granuloma diameter or intralesional T-cell phenotypes. The increase in percentage resistance to reinfection was found accompanied by increased anti SWAP IgE. Combined rGST and PZQ provided the complementary goals of improved state of resistance to reinfection 'which was compromized after cure with PZQ' and the maximal reduction in granuloma diameter.


Assuntos
Anti-Helmínticos/administração & dosagem , Glutationa Transferase/administração & dosagem , Praziquantel/administração & dosagem , Esquistossomose mansoni/tratamento farmacológico , Animais , Anticorpos Anti-Helmínticos/sangue , Quimioterapia Combinada , Imunoglobulina E/sangue , Imunoglobulina G/classificação , Imunofenotipagem , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/administração & dosagem , Recidiva , Esquistossomose mansoni/imunologia
19.
Int J Parasitol ; 30(7): 837-42, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10899528

RESUMO

This work studied the histopathological changes and the changes in the expression of macrophage adhesion molecule-1 (Mac-1) and macrophage inflammatory protein-1alpha (MIP-1alpha) in a murine model of soluble egg antigen (SEA) - induced granulomatous hyporesponsiveness. Histopathological results of hepatic sections in an SEA group showed early acceleration of ova destruction and markedly diminished granuloma cellularity with eosinophils and macrophages still being the predominant cells. Later, giant cells and pigmented macrophages that were scattered among granuloma cells and in intimate contact with the deposited eggs were more predominant in the SEA group than in the infected control group. Concurrently, the counts of Mac-1 positive cells were significantly increased in liver sections of the SEA group than the infected control group during the course of infection. MIP-1alpha showed early higher counts followed by lower counts in the later stages of infection on granuloma cells in the SEA group than the infected control group. During the course of infection, similar distribution of Mac-1 and MIP-1alpha was present in both groups. This study suggests that sensitization with SEA probably leads to enhancement of phagocytic activity of macrophages via increasing expression of Mac-1 and hence engulfment of ic3b coated schistosomal products such as ova. It leads to rapid destruction of ova and hence decreases the host inflammatory response to infection and amelioration of hepatic pathology which would be a promising approach in reduction of host morbidity and mortality.


Assuntos
Granuloma/imunologia , Proteínas Inflamatórias de Macrófagos/biossíntese , Antígeno de Macrófago 1/biossíntese , Schistosoma mansoni/imunologia , Esquistossomose mansoni/imunologia , Animais , Anticorpos Monoclonais , Antígenos de Helmintos/imunologia , Western Blotting , Quimiocina CCL3 , Quimiocina CCL4 , Regulação da Expressão Gênica , Granuloma/parasitologia , Granuloma/patologia , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Fígado/parasitologia , Fígado/patologia , Proteínas Inflamatórias de Macrófagos/análise , Antígeno de Macrófago 1/análise , Camundongos , Camundongos Endogâmicos C57BL , Esquistossomose mansoni/patologia
20.
Mar Environ Res ; 49(3): 201-15, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11285726

RESUMO

In the present study, heat-shock protein of M(r) 70 kDa (HSP70), a marker of cellular stress response, was validated as a potential biomarker under field conditions. The dab, Limanda limanda (female, size > or = 25 cm, spawning maturity stage 2) was used as the indicator organism. The data on HSP level were correlated with the occurrence of DNA damage, measured in the same specimens of L. limanda, to prove the usefulness of the method. The area under investigation was the North Sea. Four locations were selected: station N01, close to Heligoland, in the North Sea; station N04 at the Dogger Bank; station N06 at the Firth of Forth; and station G08 in the English Channel. Ten animals from each location were selected and their livers used for the experiments. The results show that the highest levels of HSP70 (consisting of two forms of M(r) 75 and 73 kDa) were in fish from station N04, while low values were measured in livers from L. limanda collected at station N01. Intermediate levels were seen in the animals from the two other locations. By application of a novel technique, it was found that the extent of DNA damage (single-strand breaks and alkaline labile sites) in fish liver parallels the levels of both HSP70 forms. Our results suggest that L. limanda may be a useful bioindicator and heat-shock proteins, a useful biomarker for monitoring of environmental pollution.


Assuntos
Dano ao DNA , Linguado/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Animais , Biomarcadores/análise , Inglaterra , Monitoramento Ambiental , Feminino , Alemanha , Fígado/metabolismo , Biologia Marinha
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