Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 63
Filtrar
1.
Environ Geochem Health ; 46(9): 305, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001968

RESUMO

Dimethoate (DMT) is one of the most harmful and commonly used organophosphate pesticides in agricultural lands to control different groups of parasitic insects. However, this pesticide is considered a dangerous pollutant for aquatic organisms following its infiltration in coastal ecosystems through leaching. Yet, our investigation aimed to gain new insights into the toxicity mechanism of DMT in the muscles of the green crab Carcinus aestuarii, regarding oxidative stress, neurotransmission impairment, histological aspects, and changes in lipid composition, assessed for the first time on the green crab's muscle. Specimens of C. aestuarii were exposed to 50, 100, and 200 µg DMT L-1 for 24 h. Compared to the negative control group, the higher the DMT concentration, the lower the saturated fatty acids (SFA), and the higher the monounsaturated fatty acids (MUFA). The significant increase in polyunsaturated fatty acid n-6 (PUFA n-6) was related to the high release, mainly, of linoleic acid (LA, C18: 2n6) and arachidonic acid (ARA, C20: 4n6) levels. Biochemical biomarkers showed that DMT exposure promoted oxidative stress, highlighted by increased levels of hydrogen peroxide (H2O2), malondialdehyde (MDA), advanced oxidation protein product levels (AOPP), and protein carbonyl (PCO). Furthermore, the antioxidant defense system was activated, as demonstrated by the significant changes in the enzymatic activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and reduced glutathione (GSH) levels associated with an adaptation process of C. aestuarii to cope with the DMT exposure. This pesticide significantly impairs the neurotransmission process, as evidenced by the inhibition of acetylcholinesterase (AChE) activity. Finally, several histopathological changes were revealed in DMT-treated crabs, including vacuolation, and muscle bundle loss.This research offered new insights into the toxic mechanism of DMT, pointing to the usefulness of fatty acid (FA) composition as a sensitive biomarker in littoral crabs.


Assuntos
Braquiúros , Dimetoato , Músculos , Estresse Oxidativo , Poluentes Químicos da Água , Animais , Dimetoato/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Braquiúros/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Músculos/efeitos dos fármacos , Músculos/metabolismo , Ácidos Graxos/metabolismo , Inseticidas/toxicidade , Biomarcadores/metabolismo , Malondialdeído/metabolismo
2.
Pestic Biochem Physiol ; 197: 105699, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38072554

RESUMO

Dimethoate is a broad-spectrum organophosphate insecticide and acaricide. Through various pathways, such as runoff and drift, dimethoate can reach marine environment, and easily impact common organisms in coastal areas, close to agriculture lands, namely crustaceans. The purpose of this study was to investigate the potential effects of dimethoate exposure (50, 100, and 200 µg/l), for 1 day, on a wide range of markers of oxidative stress and neurotransmission impairment, as well as fatty acids composition and histopathological aspect in the gills of the green crab Carcinus aestuarii. A significant increase in n-3 polyunsaturated fatty acids series, namely the eicosapentaenoic acid (C20: 5n3) and its precursor alpha-linolenic acid (C 18: 3n3) in dimethoate-treated crabs was recorded. Concerning n-6 polyunsaturated fatty acids, we noted a high reduction in arachidonic acid (C20:4n-6) levels. Dimethoate exposure increased the levels of hydrogen peroxide, malondialdehyde, lipid hydroperoxides, protein carbonyl, and caused the advanced oxidation of protein products along with enzymatic and non-enzymatic antioxidant-related markers. Acetylcholinesterase activity was highly inhibited following exposure to dimethoate in a concentration-dependent manner. Finally, deleterious histopathological changes with several abnormalities were noted in exposed animals confirming our biochemical findings. The present study offered unique insights to establish a relationship between redox status and alterations in fatty acid composition, allowing a better understanding of dimethoate-triggered toxicity.


Assuntos
Braquiúros , Dimetoato , Animais , Dimetoato/toxicidade , Braquiúros/metabolismo , Ácidos Graxos , Acetilcolinesterase/metabolismo , Brânquias , Oxirredução , Ácidos Graxos Insaturados/metabolismo , Ácidos Graxos Insaturados/farmacologia
3.
Medicina (Kaunas) ; 59(10)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37893541

RESUMO

Background and Objectives: Obesity is currently a major health problem due to fatty acid accumulation and excess intake of energy, which leads to an increase in oxidative stress, particularly in the liver. The main goal of this study is to evaluate the protective effects of spirulina (SP) against cafeteria diet (CD)-induced obesity, oxidative stress, and lipotoxicity in rats. Materials and Methods: The rats were divided into four groups and received daily treatments for eight weeks as follows: control group fed a standard diet (SD 360 g/d); cafeteria diet group (CD 360 g/d); spirulina group (SP 500 mg/kg); and CD + SP group (500 mg/kg, b.w., p.o.) according to body weight (b.w.) per oral (p.o.). Results: Our results show that treatment with a CD increased the weights of the body, liver, and abdominal fat. Additionally, severe hepatic alteration, disturbances in the metabolic parameters of serum, and lipotoxicity associated with oxidative stress in response to the CD-induced obesity were observed. However, SP treatment significantly reduced the liver alteration of CD feed and lipid profile disorder associated with obesity. Conclusions: Our findings suggest that spirulina has a marked potential therapeutic effect against obesity and mitigates disturbances in liver function parameters, histological alterations, and oxidative stress status.


Assuntos
Fígado Gorduroso , Spirulina , Ratos , Animais , Spirulina/química , Fígado Gorduroso/tratamento farmacológico , Fígado , Obesidade/metabolismo , Estresse Oxidativo
4.
Biochem Biophys Res Commun ; 530(2): 471-478, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32593416

RESUMO

Tenascin-C (TNC) and tenascin-W (TNW), large hexameric glycoproteins overexpressed in the tumor microenvironment, are useful tumor biomarkers for theranostic applications. For now, polyclonal and monoclonal antibodies, as well as aptamers targeting TNC and TNW have been developed. However, the immunostaining sensitivity of antibodies is very heterogenous. The main aim of this study was to generate antibodies in dromedary that detect TNC and TNW, respectively. We show that immune sera from immunized dromedaries are able to specifically bind native TNC and TNW by ELISA and also to detect TNC and TNW in matrix tracks of mammary tumors by immunostaining. Furthermore, we demonstrate that purified IgG subtypes are able to interact specifically with TNC or TNW by ELISA and immunostaining. These camelid antibodies are a good basis to develop tools for the detection of TNC and TNW in the tumor microenvironment and could potentially have a broader application for early diagnosis of solid cancers.


Assuntos
Anticorpos/imunologia , Camelus/imunologia , Tenascina/imunologia , Animais , Anticorpos/análise , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/imunologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Células HEK293 , Humanos , Imunização , Camundongos , Microscopia de Fluorescência , Tenascina/análise , Microambiente Tumoral
5.
J Transl Med ; 18(1): 440, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33213472

RESUMO

BACKGROUND: Platelet derived growth factor receptor alpha (PDGFRα) has been considered as a relevant factor in tumor proliferation, angiogenesis and metastatic dissemination. It was a target of tyrosine kinase (TK) inhibitors emerged in the therapy of diverse cancers. In colorectal cancer, the commonly used therapy is anti-epithelial growth factor receptor (EGFR). However, both RAS mutated and a subgroup of RAS wild type patients resist to such therapy. The aim of this study is to investigate PDGFRα protein expression and mutational status in colorectal adenocarcinoma and their association with clinicopathological features and molecular RAS status to provide useful information for the identification of an effective biomarker that might be implicated in prognosis and treatment prediction. METHODS: Our study enrolled 103 formalin fixed paraffin-embedded (FFPE) colorectal adenocarcinoma. PDGFRα expression was investigated by immunohistochemistry (IHC). Hotspot exon 18 of PDGFRA was studied by PCR followed by Sanger sequencing and RAS status was determined by real time quantitative PCR. Thirteen normal colon tissues were used as negative controls. RESULTS: PDGFRα staining was detected in the cytoplasm of all tissues. Low expression was observed in all normal colon mucosa. In adenocarcinoma, 45% (45/100) of cases showed PDGFRα overexpression. This overexpression was significantly associated with mutations in exon 18 (P = 0.024), RAS wild type status (P < 10-3), tumor diameter (P = 0.048), whereas there was no association with tumor side (P = 0.13) and other clinicopathological features. CONCLUSION: Overexpression of PDGFRα in adenocarcinoma suggests its potential role in tumor cells growth and invasion. The association between PDGFRα overexpression in both tumor and stromal adenocarcinoma cells with RAS wild type status suggests its potential role in anti-EGFR therapy resistance and the relevance of using it as specific or adjuvant therapeutic target.


Assuntos
Adenocarcinoma , Neoplasias Colorretais , Receptor alfa de Fator de Crescimento Derivado de Plaquetas , Adenocarcinoma/genética , Neoplasias Colorretais/genética , Humanos , Imuno-Histoquímica , Mutação/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Proteínas ras/genética
6.
BMC Cancer ; 20(1): 1179, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33267786

RESUMO

BACKGROUND: Gastric and colorectal cancers are the most common malignant tumours, leading to a significant number of cancer-related deaths worldwide. Recently, increasing evidence has demonstrated that cancer cells exhibit a differential expression of potassium channels and this can contribute to cancer progression. However, their expression and localisation at the somatic level remains uncertain. In this study, we have investigated the expression levels of KCNB1 and KCNA5 genes encoding ubiquitous Kv2.1 and Kv1.5 potassium channels in gastric and colorectal tumours. METHODS: Gastric and colorectal tumoral and peritumoral tissues were collected to evaluate the expression of KCNB1 and KCNA5 mRNA by quantitative PCR. Moreover, the immunohistochemical staining profile of Kv2.1 and Kv1.5 was assessed on 40 Formalin-Fixed and Paraffin-Embedded (FFPE) gastric carcinoma tissues. Differences in gene expression between tumoral and peritumoral tissues were compared statistically with the Mann-Whitney U test. The association between the clinicopathological features of the GC patients and the expression of both Kv proteins was investigated with χ2 and Fisher's exact tests. RESULTS: The mRNA fold expression of KCNB1 and KCNA5 genes showed a lower mean in the tumoral tissues (0.06 ± 0.17, 0.006 ± 0.009) compared to peritumoral tissues (0.08 ± 0.16, 0.16 ± 0.48, respectively) without reaching the significance rate (p = 0.861, p = 0.152, respectively). Interestingly, Kv2.1 and Kv1.5 immunostaining was detectable and characterised by a large distribution in peritumoral and tumoral epithelial cells. More interestingly, inflammatory cells were also stained. Surprisingly, Kv2.1 and Kv1.5 staining was undoubtedly and predominantly detected in the cytoplasm compartment of tumour cells. Indeed, the expression of Kv2.1 in tumour cells revealed a significant association with the early gastric cancer clinical stage (p = 0.026). CONCLUSION: The data highlight, for the first time, the potential role of Kv1.5 and Kv2.1 in gastrointestinal-related cancers and suggests they may be promising prognostic markers for these tumours.


Assuntos
Neoplasias Colorretais/genética , Canal de Potássio Kv1.5/metabolismo , Canais de Potássio Shab/metabolismo , Neoplasias Gástricas/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
J Transl Med ; 17(1): 212, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31248416

RESUMO

BACKGROUND: Lynch syndrome (LS) is a highly penetrant inherited cancer predisposition syndrome, characterized by autosomal dominant inheritance and germline mutations in DNA mismatch repair genes. Despite several genetic variations that have been identified in various populations, the penetrance is highly variable and the reasons for this have not been fully elucidated. This study investigates whether, besides pathogenic mutations, environment and low penetrance genetic risk factors may result in phenotype modification in a Tunisian LS family. PATIENTS AND METHODS: A Tunisian family with strong colorectal cancer (CRC) history that fulfill the Amsterdam I criteria for the diagnosis of Lynch syndrome was proposed for oncogenetic counseling. The index case was a man, diagnosed at the age of 33 years with CRC. He has a monozygotic twin diagnosed at the age of 35 years with crohn disease. Forty-seven years-old was the onset age of his paternal uncle withCRC. An immunohistochemical (IHC) labeling for the four proteins (MLH1, MSH2, MSH6 and PMS2) of the MisMatchRepair (MMR) system was performed for the index case. A targeted sequencing of MSH2, MLH1 and a panel of 85 DNA repair genes was performed for the index case and for his unaffected father. RESULTS: The IHC results showed a loss of MSH2 but not MLH1, MSH6 and PMS2 proteins expression. Genomic DNA screening, by targeted DNA repair genes sequencing, revealed an MSH2 pathogenic mutation (c.1552C>T; p.Q518X), confirmed by Sanger sequencing. This mutation was suspected to be a causal mutation associated to the loss of MSH2 expression and it was found in first and second degree relatives. The index case has smoking and alcohol consumption habits. Moreover, he harbors extensive genetic variations in other DNA-repair genes not shared with his unaffected father. CONCLUSION: In our investigated Tunisian family, we confirmed the LS by IHC, molecular and in silico investigations. We identified a novel pathogenic mutation described for the first time in Tunisia. These results come enriching the previously reported pathogenic mutations in LS families. Our study brings new arguments to the interpretation of MMR expression pattern and highlights new risk modifiers genes eventually implicated in CRC. Twins discordance reported in this work underscore that disease penetrance could be influenced by both genetic background and environmental factors.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA/genética , Doenças em Gêmeos/genética , Proteína 2 Homóloga a MutS/genética , Mutação , Adulto , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Doenças em Gêmeos/patologia , Família , Predisposição Genética para Doença , Testes Genéticos , Mutação em Linhagem Germinativa , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Polimorfismo de Nucleotídeo Único , Tunísia
8.
J Cutan Pathol ; 46(8): 591-598, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30972814

RESUMO

BACKGROUND: Several studies have reported the oncogenic role of human papillomavirus (HPV) in non-melanoma skin cancer (NMSC) carcinogenesis. Considering that HPV could affect tumor protein 53 (TP53) degradation via E6 oncoprotein, we evaluated the expression of TP53 according to HPV infection and E6 expression. METHODS: Biopsy specimens from 79 NMSCs (28 squamous cell carcinomas, 21 keratoacanthomas and 30 basal cell carcinomas) were enrolled. Nested PCR was used to detect mucosal HPV (mHPV) DNA. Genotyping was performed by reverse line hybridization. Expression of TP53 and E6 was evaluated by immunohistochemistry. RESULTS: mHPVs were detected in 34.2% (27/79) of NMSC, with 92.6% (25/27) of high-risk HPV (HR-HPV) types. HPV16-E6-positive expression was observed in all HPV16-positive samples. TP53 high expression was found in 51.4% (37/72) of specimens. In this group, 78.4% were HPV-negative (P = 0.014). TP53 expression was negative in 8/10 of HPV E6-positive specimens. Multivariate analysis showed that TP53 was associated with HPV infection independently of histopathologic type (P = 0.005). CONCLUSION: This study showed a high prevalence of mHPV in NMSC. Active infections assessed by E6 expression are associated with loss of p53 function, highlighting the involvement of mHPV in NMSC carcinogenesis.


Assuntos
Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Papillomavirus Humano 16/metabolismo , Proteínas Oncogênicas Virais/biossíntese , Infecções por Papillomavirus , Proteínas Repressoras/biossíntese , Neoplasias Cutâneas , Proteína Supressora de Tumor p53/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/virologia , Tunísia/epidemiologia
9.
Regul Toxicol Pharmacol ; 84: 9-17, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27965129

RESUMO

Enoxaparin is a low-molecular-weight heparin widely used for the prevention and treatment of thromboembolism. With the development of several enoxaparin biosimilars, real medical concerns about their safety and efficacy have been raised. This repeated dose toxicity study consists of preclinical toxicological evaluation of a biosimilar biological version of enoxaparin, the drug product "Enoxa", compared to the enoxaparin reference drug product, "Lovenox". Eighty white Wistar rats were treated with "Enoxa" versus the reference product, using subcutaneous therapeutic and toxic doses, varying from 3.5 to 100 mg/kg/day. Dose levels were adjusted and ultimately fixed at 3.5 and 20 mg/kg/day as therapeutic and toxic doses, respectively. A sodium chloride solution (0.9%) was used as the control, and the comparative study was conducted over periods of 14 and 28 days. Comparable effects were observed with few adverse effects at the administration dose of 20 mg/kg/day, for both enoxaparin biosimilar and reference products. Interestingly, mortality started only at high doses of 40 mg/kg/day and reached 25% at 100 mg/kg/day for both products. These results, as part of the recommended biosimilarity monitoring, demonstrated comparable toxicity profiles of "Enoxa" and "Lovenox" products in rats. Continuing investigation of biosimilarity on humans to confirm safety and efficacy is suggested.


Assuntos
Anticoagulantes/toxicidade , Medicamentos Biossimilares/toxicidade , Enoxaparina/toxicidade , Animais , Anticoagulantes/administração & dosagem , Biomarcadores/sangue , Medicamentos Biossimilares/administração & dosagem , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Enoxaparina/administração & dosagem , Feminino , Injeções Subcutâneas , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos Wistar , Medição de Risco , Fatores de Tempo , Testes de Toxicidade
10.
Skinmed ; 15(1): 69-71, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28270315

RESUMO

A previously healthy 70-year-old woman presented with a 5-month history of an asymptomatic keratotic, papulonodular plaque on her right forearm. The lesion started as a follicular papule followed by progressive peripheral proliferation. No record of trauma, contact with any chemicals, use of immunosuppressive drugs, or history of neoplasm was noted. Clinical examination showed an arciform plaque of 10×5 cm, with infiltrated raised borders and central atrophy (Figure 1). Drops of yellowish material exuded from the coalescent nodules constituting an elevated and indurate border. Results from physical and laboratory examinations revealed no internal organ malignancy. The remainder of the physical examination (x-ray of the forearm and serologies for HIV, hepatitis, and syphilis) was normal.


Assuntos
Acitretina/uso terapêutico , Ceratoacantoma/tratamento farmacológico , Ceratoacantoma/patologia , Ceratolíticos/uso terapêutico , Administração Oral , Idoso , Progressão da Doença , Feminino , Seguimentos , Antebraço , Humanos , Ceratoacantoma/diagnóstico , Dermatopatias/tratamento farmacológico , Dermatopatias/patologia , Resultado do Tratamento
12.
Ultrastruct Pathol ; 40(4): 176-80, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26986447

RESUMO

Mal de Meleda (MdM, MIM: 248300) is a rare autosomal recessive skin disorder characterized by diffuse palmoplantar keratoderma and transgressive keratosis with onset in early infancy. The gene responsible for MdM, ARS, encodes for Secreted Lys6/Plaur domain-containing protein 1 which is essential for epidermal homeostasis. Tight junctions have been proposed to have two mutually exclusive functions: a fence function which prevents the mixing of membrane proteins between the apical and basolateral membranes; and a gate function which controls the paracellular passage of ions and solutes between cells. In this study we report immunohistochemical investigations of tight junction proteins claudin-1 and occludin in MdM Tunisian families. Nine skin biopsies from patients with MdM were analyzed. The control group was formed by skin biopsies belonging to healthy individuals. Immunohistochemical study was performed on fixed sections from biopsies of four microns with the following polyclonal antibodies: anti-claudin-1 and anti-occludin. In control skin, claudin-1 exhibited membrane expression throughout the epidermis with increasing and upward intensity, whereas occludin was detected in the cell membrane of keratinocytes of the stratum granulosum. In MdM skin, claudin-1 was expressed throughout the thickness of the spinous layers with membrane staining, and occludin had cytoplasmic staining in the granular layer. The immunohistochemical expression of TJ proteins in MdM patients harbors premature expression of occludin and decreased expression of claudin-1, highlighting further evidence for disorders in epidermal homeostasis.


Assuntos
Claudina-1/biossíntese , Ceratodermia Palmar e Plantar/patologia , Ocludina/biossíntese , Adulto , Biomarcadores/análise , Claudina-1/análise , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Ocludina/análise , Proteínas de Junções Íntimas/análise , Proteínas de Junções Íntimas/biossíntese , Adulto Jovem
13.
Toxicol Ind Health ; 31(9): 802-10, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23363576

RESUMO

The present study was undertaken to determine whether subacute treatment with aqueous extract of carob (Ceratonia siliqua L.) pods (AECPs) protects against ethanol (EtOH)-induced oxidative stress in rat liver. Animals were divided into four groups: control, carob, EtOH and EtOH + carob. Wistar rats were intraperitoneally pretreated with AECP (600 mg/kg body weight (bw)) during 7 days and intoxicated for 6 h by acute oral administration of EtOH (6 g/kg bw) 24 h after the last injection. We found that acute administration of EtOH leads to hepatotoxicity as monitored by the increase in the levels of hepatic marker aspartate aminotransferase and alanine aminotransferase as well as hepatic tissue injury. EtOH also increased the formation of malondialdehyde in the liver, indicating an increase in lipid peroxidation and depletion of antioxidant enzyme activities as superoxide dismutase, catalase and glutathione peroxidase. Subacute carob pretreatment prevented all the alterations induced by EtOH and returned their levels to near normal. Importantly, we showed that acute alcohol increased hepatic and plasmatic hydrogen peroxide and free iron levels. The carob pretreatment reversed EtOH effects to near control levels. These data suggest that carob could have a beneficial effect in inhibiting the oxidative damage induced by acute EtOH administration and that its mode of action may involve an opposite effect on plasma and tissue-free iron accumulation. Indeed, carob can be offered as a food additive to protect against EtOH-induced oxidative damage.


Assuntos
Etanol/efeitos adversos , Galactanos/farmacologia , Mananas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Gomas Vegetais/farmacologia , Alanina Transaminase/metabolismo , Animais , Antioxidantes/farmacologia , Aspartato Aminotransferases/metabolismo , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
14.
Virol J ; 11: 199, 2014 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-25420540

RESUMO

BACKGROUND: Cell culture adaptation of very virulent infectious bursal disease virus (vvIBDV) was shown to be mainly associated with the VP2 capsid protein residues 253, 279, and 284. The single mutation A284T proved critical for cell culture tropism, but did not confer efficient virus replication, which at least required one additional mutation, Q253H or D279N. While the double mutation Q253H/A284T was unambiguously shown to confer both efficient replication in cell culture and attenuation in chickens, conflicting results have been reported regarding the replication efficiency of vvIBDV mutants bearing the D279N/A284T double mutation, and no data are hitherto available on their virulence in chickens. FINDINGS: Here we used an in vivo reverse genetics system to assess the impact of the D279N/A284T double mutation on the replication and attenuation of a chimeric IBDV virus, whose polyprotein derived from a non-culturable vvIBDV clinical isolate. We found that the D279N/A284T double mutation did indeed confer efficient replication in chicken embryo fibroblast (CEF) cell culture, but the mutant virus remained highly pathogenic to chickens. CONCLUSIONS: The double mutation D279N/A284T of the VP2 major capsid protein of vvIBDV is sufficient to confer cell culture tropism and replication efficiency, but does not necessarily lead to virus attenuation.


Assuntos
Substituição de Aminoácidos , Infecções por Birnaviridae/veterinária , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Vírus da Doença Infecciosa da Bursa/patogenicidade , Doenças das Aves Domésticas/virologia , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Infecções por Birnaviridae/virologia , Proteínas do Capsídeo/metabolismo , Embrião de Galinha , Galinhas , Vírus da Doença Infecciosa da Bursa/química , Vírus da Doença Infecciosa da Bursa/genética , Vírus da Doença Infecciosa da Bursa/fisiologia , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Alinhamento de Sequência , Tropismo Viral , Virulência , Replicação Viral
15.
Heliyon ; 10(9): e30103, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38694088

RESUMO

Objective: The cafeteria diet (CD), designed as an experimental diet mimicking the obesogenic diet, may contribute to the pathogenesis of inflammatory bowel diseases (IBD). This study delves into the influence of spirulina (SP) on obesity associated with colitis in Wistar rats. Methods: The amino acids composition of SP was analyzed using HPLC-FLD. Animals were equally separated into eight groups, each containing seven animals and treated daily for eight weeks as follows: Control diet (SD), cafeteria diet (CD) group, CD + SP (500 mg/kg) and SD + SP. Ulcerative colitis was provoked by rectal injection of acetic acid (AA) (3 % v/v, 5 ml/kg b.w.) on the last day of treatment in the following groups: SD + AA, SD + AA + SP, CD + AA, and CD + AA + SP. Results: Findings revealed that UC and/or CD increased the abdominal fat, weights gain, and colons. Moreover, severe colonic alteration, perturbations in the serum metabolic parameters associated with an oxidative stress state in the colonic mucosa, defined by overproduction of reactive oxygen species (ROS) and increased levels of plasma scavenging activity (PSA). Additionally, obesity exacerbated the severity of AA-induced UC promoting inflammation marked by the overexpression of pro-inflammatory cytokines. Significantly, treatment with SP provided notable protection against inflammation severity, reduced histopathological alterations, attenuated lipid peroxidation (MDA), and enhanced antioxidant enzyme activities (CAT, SOD, and GPX) along with non-enzymatic antioxidants (GSH and SH-G). Conclusions: Thus, the antioxidant effects and anti-inflammatory proprieties of SP could be attributed to its richness in amino acids, which could potentially mitigate inflammation severity in obese subjects suffering from ulcerative colitis. These results imply that SP hold promise as a therapeutic agent for managing of UC, particularly in individuals with concomitant obesity. Understanding SP's mechanisms of action may lead novel treatment strategies for inflammatory bowel diseases and hyperlipidemia in medical research.

16.
Transl Oncol ; 43: 101912, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38387387

RESUMO

INTRODUCTION: Cancer management in Africa faces diverse challenges due to limited resources, health system challenges, and other matters. Identifying hereditary cancer syndromic cases is crucial to improve clinical management and preventive care in these settings. This study aims to explore the clinicopathological features and genetic factors associated with hereditary cancer in Tunisia, a North African country with a rising cancer burden MATERIALS AND METHODS: Clinicopathological features and personal/family history of cancer were explored in 521 patients. Genetic analysis using Sanger and next-generation sequencing was performed for a set of patients RESULTS: Hereditary breast and ovarian cancer syndrome was the most frequent cluster in which 36 BRCA mutations were identified. We described a subgroup of patients with likely ''breast cancer-only syndrome'' among this cluster. Two cases of Li-Fraumeni syndrome with distinct TP53 mutations namely c.638G>A and c.733G>A have been identified. Genetic investigation also allowed the identification of a new BLM homozygous mutation (c.3254dupT) in one patient with multiple primary cancers. Phenotype-genotype correlation suggests the diagnosis of Bloom syndrome. A recurrent MUTYH mutation (c.1143_1144dup) was identified in three patients with different phenotypes CONCLUSION: Our study calls for comprehensive genetic education and the implementation of genetic screening in Tunisia and other African countries health systems, to reduce the burden of hereditary diseases and improve cancer outcomes in resource-stratified settings.

17.
Ultrastruct Pathol ; 37(3): 191-5, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23634793

RESUMO

BACKGROUND: Bladder cancer is a disease of older persons, the incidence of which is expected to increase as the population ages. Prognostic factors for local recurrence for patients with non-muscle invasive bladder cancer have not been fully established. The aim of our study was to determine the influence of age on the outcomes of non muscle invasive bladder (NMIBC) cancer treated with intravesical Bacillus Calmette-Guerin (BCG) therapy. METHODS: We retrospectively reviewed the clinical and pathologic data of primary NMIBC from 112 patients who were treated with transurethral resection followed by BCG-immunotherapy. Time follow-up was 30 months. Clinicopathologic characteristics and response to BCG therapy were correlated with age using univariate and multivariate methods of analysis. RESULTS: Univariate analysis showed that age analyzed as a categorical variable was not associated with other clinicopathological characteristics. On the other hand, multivariate analysis showed that only multiplicity, stage and tumor size were independent significant prognosticators. CONCLUSIONS: The results of our study have shown that aging has no impact on the outcomes of high-risk NMIBC treated by BCG immunotherapy.


Assuntos
Vacina BCG/administração & dosagem , Imunoterapia/métodos , Neoplasias da Bexiga Urinária/terapia , Administração Intravesical , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biópsia , Cistectomia/métodos , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/patologia
18.
Ultrastruct Pathol ; 37(4): 278-83, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23789613

RESUMO

BACKGROUND: pT1 bladder urothelial carcinomas represent a heterogeneous group of tumors with different biologic behaviors, and identifying the subset of tumors that carries a high risk of disease recurrence and progression is therefore important. Induction and maintenance intravesical Bacillus Calmette-Guerin (BCG) has been proven to reduce tumour recurrence and progression. However, no markers are available to predict BCG response. The aim of this study is to evaluate the prognostic factors of stage in predicting recurrence after intravesical adjuvant BCG immunotherapy in patients with NMIBC. METHODS: we retrospectively reviewed the clinical and pathologic data of primary NMIBC from 45 patients who were treated with transurethral resection followed by BCG-immunotherapy. Time follow-up was 30 months. The prognostic significance of clinicopathologics characteristics in determining the risk for recurrence after BCG therapy was studied with both univariate and multivariate methods of analysis. RESULTS: univariate Cox regression analysis of clinicopathologic characteristics revealed that the rate of recurrence was statistically associated with tumor stage. Indeed, a significant concordance was noted between the EORTC s predicted risks and the actuarial recurrence rate of NMIBC at one year. On the other hand, multivariate analysis using Cox regression based on the AIC criteria and biological considerations, selected the score of recurrence as independent predictor of recurrence. CONCLUSION: The conventional clinicopathological factors used in EORTC model are relevant for the assessment of the outcome of pT1 stage bladder tumors treated by BCG immunotherapy. Management of pT1 bladder cancer patients remains one of the most difficult problems in urologic practice. At this time the decision to preserve the bladder or to perform a cystectomy depends on a number of clinicopathologic parameters, but none are able to sufficiently identify patients for the appropriate therapeutic modality. Additional studies using a more large scale of patients will be required to confirm our findings.


Assuntos
Vacina BCG/uso terapêutico , Carcinoma de Células de Transição/tratamento farmacológico , Recidiva Local de Neoplasia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Administração Intravesical , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologia
19.
Ultrastruct Pathol ; 37(4): 249-53, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23899093

RESUMO

The authors determined the recurrence and progression at 1 year in patients with non-muscle-invasive urothelial carcinoma who underwent transurethral resection of bladder tumor (TURBT) and compared the results with the calculated risk according to the European Organization of Research and Treatment of Cancer (EORTC). Between 2002 and 2011, a total of 112 patients with NMIBC were treated with transurethral resection of bladder cancer. According to the EORTC scoring system, the patients were categorized in terms of number of tumors, tumor size, prior recurrence rate, T category, carcinoma in situ, and pathologic grade, and the scores were summed. According to the summed scores, the recurrence group and the progression group were divided into 3 subgroups: low, intermediate, and high risk, respectively. The recurrence rate and progression rate of each group were compared with the EORTC risk tables. The mean patient age was 63.9 years (range: 25-85) at diagnosis. Seventy-eight patients (68.4%) had a recurrent disease, 53 (47.3%) had a tumor larger than 3 cm in diameter, 55 (49.1%) had multiple lesions, 3 (0.26%) had carcinoma in situ, 44(39.3%) had stage T1 lesions, and 20 (17.8%) had a high-grade disease. The recurrence rates were 0, 14.2, 31.25, and 85.71% in groups with the predicted EORTC risks of 15, 24, 38, and 61%, respectively. There were 3 patients (0.2%) with progression of the diseases. The EORTC model successfully stratified recurrence and progression risks in this cohort. However, the discriminative ability of the EORTC tables decreased in these patients for progression.


Assuntos
Vacina BCG/uso terapêutico , Carcinoma de Células de Transição/patologia , Imunoterapia , Modelos Estatísticos , Software , Neoplasias da Bexiga Urinária/patologia , Administração Intravesical , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/imunologia , Carcinoma de Células de Transição/terapia , Progressão da Doença , Feminino , Humanos , Imunoterapia/métodos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Prognóstico , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/terapia
20.
Ultrastruct Pathol ; 37(1): 56-61, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23383616

RESUMO

PURPOSE: Tumor-associated macrophages can regulate the growth of various cancers positively or negatively. Intravesical bacillus Calmette-Guerin instillation is now the gold standard treatment for bladder carcinoma in situ. The authors investigated the correlation between tumor-associated macrophages infiltrating bladder carcinoma in situ and the response to intravesical bacillus Calmette-Guerin therapy. MATERIALS AND METHODS: The authors examined paraffin-embedded tissues from 41 patients with bladder carcinoma in situ who received intravesical bacillus Calmette-Guerin therapy. Tumor-associated macrophages were immunohistochemically stained by anti-CD68 monoclonal antibody. RESULTS: The median number of tumor-associated macrophages infiltrating among cancer cells and the number in the lamina propria were 4 and 24, respectively. Recurrent carcinoma in situ was found in 4.8% of cases with a lower cancer cell tumor-associated macrophage count but in 47.6% of those with a higher cancer cell tumor-associated macrophage count (less than 4 vs. 4 or greater). Recurrence was found in 31.8% of patients with a lower lamina propria tumor-associated macrophage count but in 21.1% of those with a higher lamina propria tumor-associated macrophage count (less than 25 vs. 25 or greater). The median ratio of tumor-associated macrophages among cancer cells vs. in the lamina propria was 0.2. Recurrence-free survival was significantly better in patients with a lower cancer cell tumor-associated macrophage count (p = .0002). Those with a lower cancer cell-to-lamina propria tumor-associated macrophage ratio had a higher recurrence-free rate (p < .0001). Multivariate analysis revealed that the cancer cell tumor-associated macrophage count and the cancer cell-to-lamina propria tumor-associated macrophage ratio can be prognostic factors for bladder carcinoma in situ. CONCLUSIONS: The count of tumor-associated macrophages infiltrating the cancer area is useful for predicting the response of bladder carcinoma in situ to intravesical bacillus Calmette-Guerin instillation before treatment initiation. Although on univariate analysis TAMs are associated with other poor prognosticators, on multivariate analysis, TAMs appear only to be associated with MI and VI. TAMs may play a significant role in the biology of tumor progression of endometrial adenocarcinoma, but do not appear to be independent prognostic indicators of patient's survival.


Assuntos
Administração Intravesical , Vacina BCG/administração & dosagem , Carcinoma in Situ/terapia , Imunoterapia/métodos , Macrófagos/patologia , Neoplasias da Bexiga Urinária/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Biomarcadores Tumorais/análise , Carcinoma in Situ/imunologia , Carcinoma in Situ/mortalidade , Carcinoma in Situ/patologia , Contagem de Células , Distribuição de Qui-Quadrado , Intervalo Livre de Doença , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Macrófagos/imunologia , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Recidiva Local de Neoplasia , Inclusão em Parafina , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA