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1.
Vet Pathol ; : 3009858241257908, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38859800

RESUMO

Slaughterhouse inspections play a crucial role in the sanitary control of zoonoses and foodborne diseases. This study aimed to identify and analyze the frequencies of lymph node diseases in cattle slaughtered for human consumption, using the samples sent to the anatomic pathology service of the Federal Laboratory for Agricultural Defense (Laboratório Federal de Defesa Agropecuária), Minas Gerais, Brazil, from January 2015 to September 2022. In total, 2000 lymph node samples were analyzed, and additional information was individually retrieved. Lesions were most frequently identified in thoracic lymph nodes. Bacterial isolation and quantitative polymerase chain reaction (qPCR) were performed using samples suspected of tuberculosis. Tuberculosis cases accounted for 89.3% of the samples. Histopathology was more sensitive than other ancillary tests for diagnosing tuberculosis. Paraffin-embedded tissues from lymphoma cases were subjected to immunophenotyping using anti-CD3 and anti-CD79a immunohistochemistry. Frozen and/or paraffin-embedded tissues from lymphoma cases were used to identify the enzootic bovine leukosis (EBL) retrovirus through qPCR. Other diagnoses included primary (T- and B-cell lymphoma) and metastatic neoplasms (squamous cell carcinoma, pulmonary adenocarcinoma, undifferentiated carcinoma, undifferentiated adenocarcinoma, undifferentiated sarcoma, undifferentiated round cell tumor, mesothelioma, hepatic carcinoid, meningioma, and seminoma), actinogranulomas (pyogranulomatous lymphadenitis [actinobacillosis and actinomycosis]), idiopathic lymphadenitis (neutrophilic and/or histiocytic, granulomatous, and suppurative), and miscellaneous nonspecific lymphadenopathies (depletion/lymphoid atrophy, lymphangiectasia, erythrocyte drainage, parasitic eosinophilic lymphadenitis, follicular hyperplasia, and toxic granulomatous lymphadenitis). The combination of histopathology with complementary techniques is important for successful diagnosis, especially in complex cases of high epidemiological, economic, and zoosanitary importance, such as tuberculosis and EBL.

2.
J Dairy Sci ; 107(7): 5054-5069, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38460875

RESUMO

Cattle lameness remains a significant concern, causing economic losses and compromising animal welfare. Claw horn lesions have been identified as a major cause of lameness in dairy cows, but their correlation with high-energy diets and ruminal acidosis remains unclear. Hence, the primary objective of this study was to assess the effects of a high-starch diet and a conventional diet on the rumen environment, acute-phase proteins, and metabolic alterations, with a particular focus on insulin resistance and the consequent implications for the histology of the hooves in Holstein steers. A total of 16 animals were divided into the high-starch (HS; 37% starch) and conventional (CON; 16.8% starch) groups. Glucose tolerance tests (GTT), blood analyses, rumen fluid analyses, and histological evaluations of the hoof tissue were conducted over a 102-d experimental period. The HS group showed a lower ruminal pH than the CON group, and with values indicating SARA. The plasma glucose and IGF-1 concentrations were higher in the HS group, suggesting an anabolic state. Both groups exhibited an increase in the insulin area under the curve (AUC) after the GTT on d 102. Histological analysis of the hooves showed a reduction in the length and width of the epidermal lamella in both groups. We found a significant negative correlation between the insulin AUC and the length and width of the epidermal lamella. Because both groups were similarly affected, the hypothesis that histological alterations were caused by the experimental diets still needs confirmation. Additionally, the development of SARA was not essential for the observed histological changes in the hoof. Further studies are warranted to thoroughly investigate the role of insulin and IGF-1 imbalances in claw health.


Assuntos
Acidose , Ração Animal , Dieta , Casco e Garras , Resistência à Insulina , Rúmen , Animais , Bovinos , Rúmen/metabolismo , Dieta/veterinária , Casco e Garras/patologia , Acidose/veterinária , Doenças dos Bovinos , Masculino , Coxeadura Animal , Teste de Tolerância a Glucose/veterinária
3.
Sensors (Basel) ; 23(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36904827

RESUMO

Globally, educational institutes are trying to adapt modernized and effective approaches and tools to their education systems to improve the quality of their performance and achievements. However, identifying, designing, and/or developing promising mechanisms and tools that can impact class activities and the development of students' outputs are critical success factors. Given that, the contribution of this work is to propose a methodology that can guide and usher educational institutes step by step through the implementation of a personalized package of training Toolkits in Smart Labs. In this study, the package of Toolkits refers to a set of needed tools, resources, and materials that, with integration into a Smart Lab can, on the one hand, empower teachers and instructors in designing and developing personalized training disciplines and module courses and, on the other hand, may support students (in different ways) in developing their skills. To demonstrate the applicability and usefulness of the proposed methodology, a model was first developed, representing the potential Toolkits for training and skill development. The model was then tested by instantiating a particular box that integrates some hardware to be able to connect sensors to actuators, with an eye toward implementing this system mainly in the health domain. In a real scenario, the box was used in an engineering program and its associated Smart Lab to develop students' skills and capabilities in the areas of the Internet of Things (IoT) and Artificial Intelligence (AI). The main outcome of this work is a methodology supported by a model able to represent Smart Lab assets in order to facilitate training programs through training Toolkits.


Assuntos
Inteligência Artificial , Estudantes , Humanos
4.
Int J Mol Sci ; 24(20)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37894716

RESUMO

In southern and southeastern Brazil, the TP53 founder variant c.1010G>A (R337H) has been previously documented with a prevalence of 0.3% within the general population and linked to a heightened incidence of lung adenocarcinomas (LUADs). In the present investigation, we cover clinical and molecular characterizations of lung cancer patients from the Brazilian Li-Fraumeni Syndrome Study (BLISS) database. Among the 175 diagnosed malignant neoplasms, 28 (16%) were classified as LUADs, predominantly occurring in females (68%), aged above 50 years, and never-smokers (78.6%). Significantly, LUADs manifested as the initial clinical presentation of Li-Fraumeni Syndrome in 78.6% of cases. Molecular profiling was available for 20 patients, with 14 (70%) revealing EGFR family alterations. In total, 23 alterations in cancer driver genes were identified, comprising 7 actionable mutations and 4 linked to resistance against systemic treatments. In conclusion, the carriers of TP53 R337H demonstrate a predisposition to LUAD development. Furthermore, our results indicate that environmental pollution potentially impacts the carcinogenesis of lung tumors in the carriers of TP53 R337H.


Assuntos
Adenocarcinoma de Pulmão , Síndrome de Li-Fraumeni , Neoplasias Pulmonares , Feminino , Humanos , Idoso , Síndrome de Li-Fraumeni/genética , Brasil/epidemiologia , Proteína Supressora de Tumor p53/genética , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Carcinogênese , Adenocarcinoma de Pulmão/genética , Células Germinativas/patologia
5.
Microb Ecol ; 84(2): 527-538, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34557947

RESUMO

Filamentous bacteriophages contain a single-stranded DNA genome and have a peculiar lifestyle, since they do not cause host cell lysis, but establish a persistent association with the host, often causing behavioral changes, with effects on bacterial ecology. Over the years, a gradual reduction in the incidence of bacterial wilt has been observed in some fields from Brazil. This event, which has been associated with the loss of pathogenicity of Rasltonia spp. isolates due to infection by filamentous viruses of the inovirus group, is widely reported for Ralstonia spp. Asian isolates infected by inoviruses. In an attempt to elucidate which factors are associated with the phenomenon reported in Brazil, we investigated one isolate of R. solanacearum (UB-2014), with unusual characteristics for R. solanacearum, obtained from eggplant with mild wilt symptoms. To verify if the presence of filamentous bacteriophage was related to this phenotype, we performed viral purification and nucleic acid extraction. The phage genome was sequenced, and phylogenetic analyses demonstrated that the virus belongs to the family Inoviridae and was named as Ralstonia solanacerarum inovirus Brazil 1 (RSIBR1). RSIBR1 was transmitted to R. pseudosolanacearum GMI1000, and the virus-infected GMI1000 (GMI1000 VI) isolate showed alterations in phenotypic characteristics, as well as loss of pathogenicity, similarly to that observed in R. solanacearum isolate UB-2014. The presence of virus-infected UB-2014 and GMI1000 VI plants without symptoms, after 3 months, confirms that the infected isolates can colonize the plant without causing disease, which demonstrates that the phage infection changed the behavior of these pathogens.


Assuntos
Bacteriófagos , Inovirus , Ralstonia solanacearum , Brasil , Genômica , Inovirus/genética , Filogenia , Doenças das Plantas/microbiologia , Ralstonia/genética , Ralstonia solanacearum/genética , Virulência/genética
6.
J Med Primatol ; 50(2): 99-107, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33283281

RESUMO

BACKGROUND: Toxoplasmosis is a zoonotic disease that affects humans and warm-blooded animals. This study describes an outbreak of toxoplasmosis in howler monkeys (Alouatta sp.) and survival of capuchins (Sapajus apella), under the same environmental conditions. METHODS: Howler monkeys were submitted to post-mortem examination. Tissue samples were processed to histopathology and immunohistochemistry to detect lesions and tachyzoites of Toxoplasma gondii. Tissue samples were also frozen and submitted to PCR and genotyping of T. gondii. RESULTS: Typical lesions were observed in several organs including the liver, lymph node, and brain, with intralesional cysts and tachyzoites of T. gondii demonstrated by immunohistochemistry. T. gondii genomic sequences were amplified by PCR, and genotyping characterized the same T. gondii clone in all howler monkeys. CONCLUSIONS: Our results support the notion that some species of neotropical primates are highly susceptible to toxoplasmosis and the hypothesis that capuchins (S. apella) may be resistant.


Assuntos
Alouatta , Genótipo , Doenças dos Macacos/parasitologia , Toxoplasma/genética , Toxoplasmose Animal/parasitologia , Animais , Animais de Zoológico , Brasil/epidemiologia , Feminino , Masculino , Doenças dos Macacos/epidemiologia , Sapajus apella/parasitologia , Sapajus apella/fisiologia , Toxoplasmose Animal/epidemiologia
7.
J Pathol ; 251(1): 4-11, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31994197

RESUMO

Head and neck squamous cell carcinomas (HNSCCs) associated with human papillomavirus (HPV) occur specifically in the tonsils and the tongue base, but the reasons for this specificity remain unknown. We studied the distribution of oral and pharyngeal lesions in HPV16-transgenic mice where the expression of all the HPV16 early genes is targeted to keratinising squamous epithelia by the cytokeratin 14 (Krt14) gene promoter. At 30 weeks of age, 100% of mice developed low- and high-grade intraepithelial dysplasia at multiple sites. Twenty per cent of animals developed invasive cancers that remarkably were restricted to the tongue base, in association with the circumvallate papilla. The lesions maintained expression of CK14 (KRT14) and the HPV16 E6 and E7 oncogenes, and displayed deregulated cell proliferation and up-regulation of p16INK4A . Malignant lesions were poorly differentiated and destroyed the tongue musculature. We hypothesised that the tongue base area might contain a transformation zone similar to those observed in the cervix and anus, explaining why HPV-positive cancers target that area specifically. Immunohistochemistry for two transformation zone markers, CK7 (KRT7) and p63 (TP63), revealed a squamocolumnar junction in the terminal duct of von Ebner's gland, composed of CK7+ luminal cells and p63+ basal cells. Dysplastic and invasive lesions retained diffuse p63 expression but only scattered positivity for CK7. Site-specific HPV-induced carcinogenesis in the tongue base may be explained by the presence of a transformation zone in the circumvallate papilla. This mouse model reproduces key morphological and molecular features of HPV-positive HNSCC, providing a unique in vivo tool for basic and translational research. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Carcinoma de Células Escamosas/virologia , Neoplasias de Cabeça e Pescoço/virologia , Papillomavirus Humano 16/genética , Papillomaviridae/genética , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/patologia , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , DNA Viral/genética , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Camundongos Transgênicos , Infecções por Papillomavirus/virologia
8.
J Pathol ; 251(4): 411-419, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32488868

RESUMO

Penile cancer is an under-studied disease that occurs more commonly in developing countries and 30-50% of cases show high-risk human papillomavirus (HPV) infection. Therapeutic advances are slow, largely due to the absence of animal models for translational research. Here, we report the first mouse model for HPV-related penile cancer. Ten-week-old mice expressing all the HPV16 early genes under control of the cytokeratin 14 (Krt14) gene promoter and matched wild-type controls were exposed topically to dimethylbenz(a)anthracene (DMBA) or vehicle for 16 weeks. At 30 weeks of age, mice were sacrificed for histological analysis. Expression of Ki67, cytokeratin 14, and of the HPV16 oncogenes E6 and E7 was confirmed using immunohistochemistry and quantitative PCR, respectively. HPV16-transgenic mice developed intraepithelial lesions including condylomas and penile intraepithelial neoplasia (PeIN). Lesions expressed cytokeratin 14 and the HPV16 oncogenes E6 and E7 and showed deregulated cell proliferation, demonstrated by Ki67-positive supra-basal cells. HPV16-transgenic mice exposed to DMBA showed increased PeIN incidence and squamous cell carcinoma. Malignant lesions showed varied histological features closely resembling those of HPV-associated human penile cancers. Wild-type mice showed no malignant or pre-malignant lesions even when exposed to DMBA. These observations provide the first experimental evidence to support the etiological role of HPV16 in penile carcinogenesis. Importantly, this is the first mouse model to recapitulate key steps of HPV-related penile carcinogenesis and to reproduce morphological and molecular features of human penile cancer, providing a unique in vivo tool for studying its biology and advancing basic and translational research. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Carcinoma in Situ/virologia , Carcinoma de Células Escamosas/virologia , Papillomavirus Humano 16/fisiologia , Infecções por Papillomavirus/virologia , Neoplasias Penianas/virologia , Animais , Carcinogênese , Carcinoma in Situ/patologia , Carcinoma de Células Escamosas/patologia , Proliferação de Células , Modelos Animais de Doenças , Papillomavirus Humano 16/genética , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Transgênicos , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Neoplasias Penianas/patologia , Pênis/patologia , Pênis/virologia , Distribuição Aleatória , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
9.
Plant Dis ; 104(4): 1019-1025, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31994983

RESUMO

Bacterial wilt-causing Ralstonia threaten numerous crops throughout the world. We studied the population structure of 196 isolates of Ralstonia solanacearum and 39 isolates of Ralstonia pseudosolanacearum, which were collected from potato- and tomato-growing areas in 19 states of Brazil. Regardless of the species, three groups of isolates were identified. One group encompassed R. pseudosolanacearum isolates. The other two groups comprise isolates of R. solanacearum (phylotype II) split according to geographic regions, one made of isolates from the North and Northeast and the other made of isolates from the Central, Southeast, and South regions (CSS). Among the isolates collected in CSS, those from tomato were genetically distinct from the potato isolates. The genetic variability in the population of R. pseudosolanacearum was lower than that of R. solanacearum, suggesting that the former was introduced in Brazil. Conversely, the high genetic variability of R. solanacearum in all regions, hosts, and times supports the hypothesis that this species is autochthonous in South America, more precisely in Brazil and Peru. For R. solanacearum, higher variability and lower migration rates were observed when tomato isolates were analyzed, indicating that the variability is caused mainly by the differences of the local, native soil population. The North subpopulation was distinct from all others, possibly because of differences in environmental features of this region. The proximity of some geographic regions and the movement of potato tubers could have facilitated migration and therefore low genetic differentiation between geographic regions. Finally, geography, which also influences host distribution, affects the structure of the population of R. solanacearum in Brazil. Despite quarantine procedures in Brazil, increasing levels of trade are a threat to biosecurity, and these results emphasize the need for improving our regional efforts to prevent the dispersal of pathogens.


Assuntos
Ralstonia solanacearum , Brasil , Estruturas Genéticas , Peru , Filogenia , Doenças das Plantas , Ralstonia
10.
Muscle Nerve ; 60(2): 188-191, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31050006

RESUMO

INTRODUCTION: Some myasthenia gravis (MG) patients are refractory to conventional treatments. METHODS: To describe the clinical features of refractory MG (RMG) and explore the association with human leukocyte antigen HLA-DRB1 alleles, a cohort study of 114 consecutive MG patients was performed. Patients were classified as RMG based on predefined criteria. RESULTS: Twenty-two patients were found to have RMG (19.3%). There were no differences between non-RMG and RMG patients with respect to sex, age of onset, abnormal 3-Hz repetitive nerve stimulation, anti-acetylcholine receptor antibody positivity, thymectomy, thymoma or thymic hyperplasia, and polyautoimmunity. HLA-DRB1*03 was more frequent in the non-RMG vs. control population (P = 3 × 10-6 ). The HLA-DRB1*13 allele was less frequent in non-RMG patients compared with controls (P = 0.002), and less frequent in the non-RMG group compared with the RMG group (P = 0.003). DISCUSSION: HLA-DRB1*03 was more common in non-RMG, and the HLA-DRB1*13 allele appeared to have a protective role, as reported previously in other autoimmune disorders. Muscle Nerve 60: 188-191, 2019.


Assuntos
Cadeias HLA-DRB1/genética , Miastenia Gravis/genética , Adulto , Idade de Início , Autoanticorpos/imunologia , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/epidemiologia , Miastenia Gravis/imunologia , Portugal/epidemiologia , Fatores de Proteção , Receptores Colinérgicos/imunologia , Timectomia/estatística & dados numéricos , Timoma/epidemiologia , Hiperplasia do Timo/epidemiologia , Neoplasias do Timo/epidemiologia , Adulto Jovem
11.
Oral Dis ; 25(5): 1291-1301, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30866167

RESUMO

OBJECTIVES: Bub3 and Spindly are essential proteins required for the activation and inactivation of the spindle assembly checkpoint, respectively. Here, we explored the clinicopathological significance and the therapeutic potential of the opposing roles of the two proteins in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Bub3 and Spindly expression was evaluated by immunohistochemistry in 62 tissue microarrays from OSCC and by real-time PCR in OSCC cell lines and in normal human oral keratinocytes. The results were analyzed as to their clinicopathological significance. RNA interference-mediated Spindly or Bub3 inhibition was combined with cisplatin treatment, and the effect on the viability of OSCC cells was assessed. RESULTS: Overexpression of Bub3 and Spindly was detected in OSCC patients. High expression of Spindly, Bub3, or both was an independent prognostic indicator for cancer-specific survival and was associated with increased cellular proliferation. Accordingly, Bub3 and Spindly were upregulated in OSCC cells comparatively to their normal counterpart. Inhibition of Bub3 or Spindly was cytotoxic to OSCC cells and enhanced their chemosensitivity to cisplatin. CONCLUSIONS: The data point out Bub3 and Spindly as potential markers of proliferation and prognosis, and highlight the potential therapeutic benefit of combining their inhibition with cisplatin.


Assuntos
Carcinoma de Células Escamosas/genética , Proteínas de Ciclo Celular/genética , Neoplasias Bucais/genética , Proteínas de Ligação a Poli-ADP-Ribose/genética , Antineoplásicos , Linhagem Celular Tumoral , Proliferação de Células , Cisplatino , Humanos , Prognóstico
12.
Drug Dev Res ; 80(6): 824-830, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31301186

RESUMO

The nuclear factor kappa light chain enhancer of activated B cells (NF-κB) has been implicated in the progression of cancers induced by high-risk human papillomaviruses (HPV). In cancer patients, NF-κB is also thought to drive a chronic systemic inflammatory status, leading to cachexia. This study addressed the ability of dimethylaminoparthenolide (DMAPT), a water-soluble NF-κB inhibitor, to block the development of HPV-induced lesions and wasting syndrome in HPV16-transgenic mice. Mice received DMAPT orally (100 mg/kg/day), once a day, for 6 consecutive weeks. Body weight was monitored weekly along with food and water intake. After 6 weeks the animals were submitted to a grip strength test and sacrificed for specimen collection. Skin samples were analyzed histologically and for expression of NF-κB-regulated genes Bcl2 and Bcl2l1. Gastrocnemius muscles were weighted and analyzed for expression of NF-κB subunits p50, p52, p65, and Rel-B. DMAPT reduced the incidence of epidermal dysplasia (18.2% versus 33.3% in HPV16+/- untreated mice). This was associated with reduced expression of Bcl2 and Bcl2l1 (p = .0003 and p = .0014, respectively) and reduced neutrophilic infiltration (p = .0339). Treated mice also showed partially preserved bodyweight and strength, which were independent of the expression levels of NF-κB subunits in skeletal muscle.These results suggest that NF-κB inhibition may be a valid strategy against HPV-induced lesions in vivo and warrant further preclinical tests particularly in the set of combination therapies. In addition, the data may support the use of DMAPT to prevent wasting syndrome.


Assuntos
Músculo Esquelético/efeitos dos fármacos , Infecções por Papillomavirus/tratamento farmacológico , Sesquiterpenos/uso terapêutico , Pele/efeitos dos fármacos , Síndrome de Emaciação/tratamento farmacológico , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Força da Mão , Papillomavirus Humano 16 , Camundongos Transgênicos , Músculo Esquelético/metabolismo , NF-kappa B/metabolismo , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Pele/metabolismo , Pele/patologia , Síndrome de Emaciação/genética , Síndrome de Emaciação/metabolismo , Síndrome de Emaciação/patologia
13.
J Sci Food Agric ; 99(9): 4248-4259, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30801730

RESUMO

BACKGROUND: Silver nanoparticles (AgNPs), particularly those entrapped in polymeric nanosystems, have arisen as options for managing plant bacterial diseases. Among the biopolymers useful for the entrapment of AgNPs, chitosan is promising because of its low cost, good biocompatibility, antimicrobial properties and biodegradability. The present study aimed: (i) to greenly-synthesize AgNPs using different concentrations of aqueous extract of tomato leaves followed by entrapment of AgNPs with chitosan (CH-AgNPs); (ii) to characterize the optical, structural and biological properties of the nanosystems produced; (iii) to evaluate the antimicrobial activities of AgNPs and nanomaterials; and (iv) to assess the effectiveness of AgNPs and nanomaterials for controlling tomato bacterial wilt caused by Ralstonia solanacearum. RESULTS: Spherical and oval AgNPs had incipient colloidal instability, although the concentration of the tomato leaf extract influenced both size (< 87 nm) and the polydispersity index. Nanomaterials (< 271 nm in size) were characterized by a highly stable matrix of chitosan containing polydisperse AgNPs. Free AgNPs and CH-AgNPs were stable for up to 30 days, with no significant alteration in physicochemical parameters. The AgNPs and nanomaterials had antibacterial activity and decreased bacterial growth at micromolar concentrations after 48 h. Morphological changes in R. solanacearum cells were observed after treatment with CH-AgNPs. The application of CH-AgNPs at 256 µmol L-1 reduced the incidence of bacterial wilt in a partially resistant tomato genotype but not in the susceptible line. CONCLUSION: Greenly-synthesized chitosan-derived nanomaterials containing AgNPs produced with leaf extracts from their own species appear to comprise a promising and sustainable alternative in an integrated management approach aiming to reduce the yield losses caused by bacterial wilt. © 2019 Society of Chemical Industry.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Quitosana/química , Química Verde/métodos , Doenças das Plantas/microbiologia , Extratos Vegetais/química , Prata/farmacologia , Solanum lycopersicum/química , Antibacterianos/química , Portadores de Fármacos/química , Composição de Medicamentos , Solanum lycopersicum/microbiologia , Nanoestruturas/química , Folhas de Planta/química , Ralstonia/efeitos dos fármacos , Ralstonia/crescimento & desenvolvimento , Prata/química
14.
BMC Biol ; 15(1): 24, 2017 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-28347335

RESUMO

BACKGROUND: The fate of hydrogen peroxide (H2O2) in the endoplasmic reticulum (ER) has been inferred indirectly from the activity of ER-localized thiol oxidases and peroxiredoxins, in vitro, and the consequences of their genetic manipulation, in vivo. Over the years hints have suggested that glutathione, puzzlingly abundant in the ER lumen, might have a role in reducing the heavy burden of H2O2 produced by the luminal enzymatic machinery for disulfide bond formation. However, limitations in existing organelle-targeted H2O2 probes have rendered them inert in the thiol-oxidizing ER, precluding experimental follow-up of glutathione's role in ER H2O2 metabolism. RESULTS: Here we report on the development of TriPer, a vital optical probe sensitive to changes in the concentration of H2O2 in the thiol-oxidizing environment of the ER. Consistent with the hypothesized contribution of oxidative protein folding to H2O2 production, ER-localized TriPer detected an increase in the luminal H2O2 signal upon induction of pro-insulin (a disulfide-bonded protein of pancreatic ß-cells), which was attenuated by the ectopic expression of catalase in the ER lumen. Interfering with glutathione production in the cytosol by buthionine sulfoximine (BSO) or enhancing its localized destruction by expression of the glutathione-degrading enzyme ChaC1 in the lumen of the ER further enhanced the luminal H2O2 signal and eroded ß-cell viability. CONCLUSIONS: A tri-cysteine system with a single peroxidatic thiol enables H2O2 detection in oxidizing milieux such as that of the ER. Tracking ER H2O2 in live pancreatic ß-cells points to a role for glutathione in H2O2 turnover.


Assuntos
Retículo Endoplasmático/metabolismo , Peróxido de Hidrogênio/metabolismo , Sondas Moleculares/metabolismo , Fenômenos Ópticos , Animais , Catálise , Linhagem Celular , Retículo Endoplasmático/efeitos dos fármacos , Fluorescência , Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Cinética , Camundongos , Oxirredução , Compostos de Sulfidrila/metabolismo
15.
Int J Exp Pathol ; 98(1): 40-46, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28556395

RESUMO

Exercise training is thought to play a protective role against cancer development and metastasis, either by reducing hormonal stimulation of hormone-dependent cancers or by reducing the permeability of vascular walls towards invading metastatic cells. The purpose of this work was to evaluate the role of long-term exercise training in the development and metastasis of breast cancer, in an immune-competent 1-methyl-1-nitrosourea (MNU) induced rat model. A single MNU dose was administered to Sprague-Dawley rats at 50 days of age and the rats were subjected to exercise training on a treadmill at 20 m/min, 60 min/day, 5 days/week for 35 weeks. Exercised animals developed slightly less (2.30 ± 1.42) tumours per animal than sedentary animals (2.55 ± 1.44) and did not develop any metastasis, while two pulmonary metastases were observed in the sedentary group. All primary neoplasms and their metastases were positive for oestrogen (ER) α and progesterone (PR) receptors, indicating high hormonal sensitivity. Interestingly, exercise training increased circulating oestrogen levels, thus suggesting that the mechanism might involve either or both of a protective hormone-independent effect and modulation of tumoural vascularization.


Assuntos
Neoplasias da Mama/patologia , Receptor alfa de Estrogênio/metabolismo , Estrogênios/metabolismo , Condicionamento Físico Animal , Animais , Neoplasias da Mama/metabolismo , Modelos Animais de Doenças , Feminino , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/secundário , Neovascularização Patológica , Ratos , Ratos Sprague-Dawley
16.
BMC Urol ; 17(1): 12, 2017 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-28143503

RESUMO

BACKGROUND: In this study we sought if, in their quest to handle hypoxia, prostate tumors express target hypoxia-associated molecules and their correlation with putative functional genetic polymorphisms. METHODS: Representative areas of prostate carcinoma (n = 51) and of nodular prostate hyperplasia (n = 20) were analysed for hypoxia-inducible factor 1 alpha (HIF-1α), carbonic anhydrase IX (CAIX), lysyl oxidase (LOX) and vascular endothelial growth factor (VEGFR2) immunohistochemistry expression using a tissue microarray. DNA was isolated from peripheral blood and used to genotype functional polymorphisms at the corresponding genes (HIF1A +1772 C > T, rs11549465; CA9 + 201 A > G; rs2071676; LOX +473 G > A, rs1800449; KDR - 604 T > C, rs2071559). RESULTS: Immunohistochemistry analyses disclosed predominance of positive CAIX and VEGFR2 expression in epithelial cells of prostate carcinomas compared to nodular prostate hyperplasia (P = 0.043 and P = 0.035, respectively). In addition, the VEGFR2 expression score in prostate epithelial cells was higher in organ-confined and extra prostatic carcinoma compared to nodular prostate hyperplasia (P = 0.031 and P = 0.004, respectively). Notably, for LOX protein the immunoreactivity score was significantly higher in organ-confined carcinomas compared to nodular prostate hyperplasia (P = 0.015). The genotype-phenotype analyses showed higher LOX staining intensity for carriers of the homozygous LOX +473 G-allele (P = 0.011). Still, carriers of the KDR-604 T-allele were more prone to have higher VEGFR2 expression in prostate epithelial cells (P < 0.006). CONCLUSIONS: Protein expression of hypoxia markers (VEGFR2, CAIX and LOX) on prostate epithelial cells was different between malignant and benign prostate disease. Two genetic polymorphisms (LOX +473 G > A and KDR-604 T > C) were correlated with protein level, accounting for a potential gene-environment effect in the activation of hypoxia-driven pathways in prostate carcinoma. Further research in larger series is warranted to validate present findings.


Assuntos
Polimorfismo Genético , Hiperplasia Prostática/genética , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Idoso , Anidrase Carbônica IX/biossíntese , Hipóxia Celular/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Fenótipo , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Proteína-Lisina 6-Oxidase/biossíntese , Fator A de Crescimento do Endotélio Vascular/biossíntese
17.
Parasitol Res ; 116(9): 2479-2488, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28702802

RESUMO

Non-human primates are our closest relatives and represent an interesting model for comparative parasitological studies. However, research on this topic particularly in relation to intestinal parasites has been fragmentary and limited mainly to animals held in captivity. Thus, our knowledge of host-parasite relationships in this species-rich group of mammals could be considered rudimentary. The current study combined morphological, ultrastructural, and molecular analyses to characterize isolates of intestinal tetratrichomonads recovered from the feces of three species of South American, non-human primates. Fecal samples were collected from 16 animals, representing 12 distinct species. Parabasalid-like organisms were evident in five samples (31%) of feces: two from Alouatta sara, two from Callithrix penicillata, and one from Sapajus apella. The five samples presented morphologies consistent with the description of Tetratrichomonas sp., with four anterior flagella of unequal length, a well-developed undulating membrane, and a long recurrent flagellum. Sequencing of the ITS1-5.8S rRNA-ITS2 region demonstrated that the isolates from A. sara, and C. penicillata were closely related and highly similar to isolates of Tetratrichomonas brumpti, recovered previously from tortoises (Geochelone sp.). The flagellate recovered from S. apella demonstrated a similar morphology to those of the other isolates, however, sequence analysis showed it to be identical to an isolate of Tetratrichomonas sp. recovered from white-lipped peccaries (Tayassu pecari). The findings of this study extend and enhance our knowledge of parasitism of non-human primates by members of the genus Tetratrichomonas and indicate that the host range of these parasites is broader than previously believed.


Assuntos
Intestinos/parasitologia , Primatas/parasitologia , Trichomonadida/isolamento & purificação , Animais , Brasil , Fezes/parasitologia , Filogenia , RNA Ribossômico , Trichomonadida/genética , Trichomonadida/ultraestrutura
18.
Korean J Parasitol ; 55(3): 239-246, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28719948

RESUMO

Strains of Toxoplasma gondii in Brazil are highly genetically diverse compared to strains from North America and Europe. Dogs are epidemiologically important because they act as sentinels for T. gondii infections in humans and are good indicators of environmental contamination. The aim of this study was to isolate and genetically characterize T. gondii strains from tissues of naturally infected Brazilian dogs. For this study, 21 blood samples were collected from dogs at the Zoonosis Control Centers of Ilhéus and Itabuna cities, Bahia, Brazil. The sera were examined for T. gondii antibodies using the indirect hemagglutination test. Brains and hearts of seropositive dogs were bioassayed in mice to isolate and characterize T. gondii parasites by PCR-RFLP using 10 genetic markers (SAG1, newSAG2, SAG3, BTUB, c22-8, c29-2, GRA6, PK1, APICO, and L358). However, T. gondii was isolated from only 4 (57.1%) dogs, designated TgDgBr6, 13, 17, and 21. All strains were virulent, causing clinical changes (rough hair coat, lethargy, and abdominal distention) and the death of all mice within 8-20 days after inoculation. Genetic analysis of these 4 T. gondii isolates revealed 4 distinct genotypes with different clonal lineage combinations (types I, II, and III) and 2 atypical alleles. Using PCR-RFLP with several markers, this study contributes to evaluations of the genetic diversity of strains circulating in Brazil.


Assuntos
Doenças do Cão/parasitologia , Cães/parasitologia , Genótipo , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Alelos , Animais , Anticorpos Antiprotozoários/sangue , Encéfalo/parasitologia , Brasil , Variação Genética , Técnicas de Genotipagem , Coração/parasitologia , Humanos , Camundongos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Toxoplasma/imunologia , Toxoplasma/patogenicidade , Virulência
19.
Syst Parasitol ; 94(1): 151-157, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28062994

RESUMO

A new species of coccidian, Isospora guaxi n. sp., and Isospora bellicosa Upton, Stamper & Whitaker, 1995 (Protozoa: Apicomplexa: Eimeriidae) are recorded from red-rumped caciques Cacicus haemorrhous (L.) in the Parque Nacional do Itatiaia, Brazil. Isospora guaxi n. sp. has sub-spheroidal oöcysts, measuring on average 30.9 × 29.0 µm, with smooth, bi-layered wall c.1.9 µm thick. Micropyle and oöcyst residuum are absent, but a polar granule is present. Sporocysts are ellipsoidal, measuring on average 19.3 × 13.8 µm. Stieda body is knob-like and sub-Stieda body is prominent and compartmentalized. Sporocyst residuum is composed of scattered granules. Sporozoites are vermiform, with one refractile body and a nucleus. Isospora bellicosa has sub-spheroidal to ovoidal oöcysts, measuring on average 27.1 × 25.0 µm, with smooth, bi-layered wall c.1.5 µm thick. Micropyle and oöcyst residuum are absent, but one or two polar granules are present. Sporocysts are ellipsoidal, measuring on average 18.1 × 10.9 µm. Stieda body is knob-like and sub-Stieda body is rounded to rectangular. Sporocyst residuum is composed of a cluster of compact or diffuse granules. Sporozoites are vermiform, with one refractile body and a nucleus. Isospora bellicosa was originally described from the Peruvian meadowlark Sturnella bellicosa deFilippi, a trans-Andean icterid which is allopatric with the cis-Andean C. haemorrhous. Therefore, in conclusion, this current study reveals the dispersion of coccidia from Icteridae across the Andes Mountains, besides describing the sixth isosporoid coccidium infecting an icterid bird.


Assuntos
Coccídios/fisiologia , Isospora/classificação , Isospora/fisiologia , Passeriformes/parasitologia , Animais , Brasil , Demografia , Isospora/citologia , Oocistos/citologia , Especificidade da Espécie , Esporozoítos/citologia
20.
Int J Cancer ; 139(8): 1715-20, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27280781

RESUMO

Male breast cancer (MBC) patients seem to have inferior survival compared to female (FBC) ones, which is not fully explained by usual prognostic factors. Recurrence analysis could show differences in relapse patterns and/or in patients' approaches that justify these outcomes. Retrospective analysis of MBC patients treated in a cancer center between 1990 and 2014, looking for relapse. For each patient, three matched FBC patients were selected by: diagnosis' year, age (within 5 years), stage and tumors' type (only luminal-like were considered). Differences between cohorts were assessed by χ(2) test and hierarchical clustering was performed to define subgroups according to relapse local. Survival curves were calculated by Kaplan-Meier and compared using log-rank test. Statistical significance was defined as p < 0.05. Groups were balanced according to age, histological grade, stage, expression of hormonal receptors and adjuvant treatments. Median time to recurrence was equivalent, p = 0.72, with the majority of patients presented with distant metastases, p = 0.69, with more lung involvement in male, p = 0.003. Male patients were more often proposed to symptomatic treatment (21.1% vs. 4.4%, p = 0.02). Overall and from recurrence survivals were poorer for male, median: 5 years [95% confidence interval (CI): 4.1-5.9 years] and 1 year (95% CI: 0-2.1 years) vs. 10 years (95% CI: 7.8-12.2 years) and 2 years (95% CI: 1.6-2.4 years), p < 0.001 and p = 0.004, respectively, and this tendency remained in the five cluster subgroups, that identified five patterns of relapse, p = 0.003. MBC patients had the worst survival, even after controlling important factors, namely the local of relapse. Palliative systemic treatment had favorable impact in prognosis and its frequently avoidance in male could justify the outcomes differences.


Assuntos
Neoplasias da Mama Masculina/diagnóstico , Neoplasias da Mama Masculina/terapia , Recidiva Local de Neoplasia/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/terapia , Neoplasias da Mama Masculina/epidemiologia , Análise por Conglomerados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Portugal/epidemiologia , Prognóstico , Fatores Sexuais , Análise de Sobrevida
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