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1.
J Gastrointest Cancer ; 54(1): 96-103, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35028828

RESUMO

BACKGROUND: Poor prognosis and short survival of patients harboring pancreatic cancer emerge how advanced disease it is. In a trial to achieve the earliest and most accurate diagnosis to manage this progressive disease, we proposed that using endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) with an adjuvant diagnostic immunohistochemical marker would give better diagnostic results. IMP3 has gained recently wide attention, as many studies found that IMP3 has not only diagnostic but also prognostic role in different types of malignancies. AIM OF THE STUDY: This prospective work is to assess the diagnostic role of EUS-FNA combined with the immunohistochemical expression of IMP3 on different benign and malignant pancreatic lesions. MATERIAL AND METHOD: The included pancreatic lesions (n = 140) were obtained by EUS-FNA technique and stained for IMP3 immunohistochemically. Paraffin blocks from patients who underwent excision (n = 92) or core biopsies (n = 48) were performed for confirming diagnosis. RESULTS: The combined method for diagnosis showed that IMP3 was positive in 78.7%, 91.7%, 100% PAC, mucinous neoplasm with high grade dysplasia, and IPMN with high grade dysplasia, respectively, while almost all benign lesions showed negative IMP3. Also, this method showed sensitivity (78.26%), specificity (95.83%), and accuracy (84.3%). CONCLUSION: EUS-FNA cytology with IMP3 could be a reliable diagnostic tool especially for assessment of malignant pancreatic lesions.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Neoplasias Pancreáticas , Humanos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Estudos Prospectivos
2.
Dermatol Ther ; 35(4): e15315, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35023272

RESUMO

Basal cell carcinoma (BCC) is the most common malignant skin tumor. While slowly growing, it can cause major skin disfigurement. Therefore, novel cosmetically acceptable treatment options, other than surgery require investigation. The aim of the study was to evaluate efficacy and safety of intralesional methotrexate (MTX) as a convenient modality for BCC treatment clinically and pathologicaly. A total of 20 patients with BCC of any clinical variant underwent intralesional MTX injection at a maximum 1 mL of 25 mg/mL MTX per session. Histopathological assessments were performed before and 1 month after treatment. Forty percent of patients showed >50% clinical improvement after 1-4 sessions. Intralesional MTX is a suitable and safe treatment modality for BCC and may be used as an adjuvant to surgery.


Assuntos
Carcinoma Basocelular , Neoplasias Cutâneas , Carcinoma Basocelular/induzido quimicamente , Carcinoma Basocelular/tratamento farmacológico , Humanos , Injeções Intralesionais , Metotrexato , Pele/patologia , Neoplasias Cutâneas/patologia
3.
Science ; 371(6524)2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33243850

RESUMO

Factor-dependent transcription termination mechanisms are poorly understood. We determined a series of cryo-electron microscopy structures portraying the hexameric adenosine triphosphatase (ATPase) ρ on a pathway to terminating NusA/NusG-modified elongation complexes. An open ρ ring contacts NusA, NusG, and multiple regions of RNA polymerase, trapping and locally unwinding proximal upstream DNA. NusA wedges into the ρ ring, initially sequestering RNA. Upon deflection of distal upstream DNA over the RNA polymerase zinc-binding domain, NusA rotates underneath one capping ρ subunit, which subsequently captures RNA. After detachment of NusG and clamp opening, RNA polymerase loses its grip on the RNA:DNA hybrid and is inactivated. Our structural and functional analyses suggest that ρ, and other termination factors across life, may use analogous strategies to allosterically trap transcription complexes in a moribund state.


Assuntos
Adenosina Trifosfatases/química , RNA Polimerases Dirigidas por DNA/química , Escherichia coli/genética , Fator Rho/química , Elongação da Transcrição Genética , Microscopia Crioeletrônica , Proteínas de Escherichia coli/química , Complexos Multiproteicos/química , Fatores de Alongamento de Peptídeos/química , Conformação Proteica , Transporte Proteico , Fatores de Transcrição/química , Fatores de Elongação da Transcrição/química , Dedos de Zinco
4.
Nat Commun ; 11(1): 6418, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33339827

RESUMO

Cellular RNA polymerases (RNAPs) can become trapped on DNA or RNA, threatening genome stability and limiting free enzyme pools, but how RNAP recycling into active states is achieved remains elusive. In Bacillus subtilis, the RNAP δ subunit and NTPase HelD have been implicated in RNAP recycling. We structurally analyzed Bacillus subtilis RNAP-δ-HelD complexes. HelD has two long arms: a Gre cleavage factor-like coiled-coil inserts deep into the RNAP secondary channel, dismantling the active site and displacing RNA, while a unique helical protrusion inserts into the main channel, prying the ß and ß' subunits apart and, aided by δ, dislodging DNA. RNAP is recycled when, after releasing trapped nucleic acids, HelD dissociates from the enzyme in an ATP-dependent manner. HelD abundance during slow growth and a dimeric (RNAP-δ-HelD)2 structure that resembles hibernating eukaryotic RNAP I suggest that HelD might also modulate active enzyme pools in response to cellular cues.


Assuntos
Bacillus subtilis/enzimologia , Proteínas de Bactérias/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Nucleosídeo-Trifosfatase/metabolismo , Subunidades Proteicas/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas de Bactérias/química , Domínio Catalítico , RNA Polimerases Dirigidas por DNA/química , Modelos Moleculares , Nucleosídeo-Trifosfatase/química , Multimerização Proteica , Subunidades Proteicas/química
5.
Naunyn Schmiedebergs Arch Pharmacol ; 393(12): 2411-2425, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32710137

RESUMO

Cisplatin and oxaliplatin are widely used anticancer drugs. Their use is restricted by their dose-limiting side effects: nephrotoxicity and neurotoxicity, respectively. Cerium oxide nanoparticles (CONPs) are promising antioxidant and anti-inflammatory agent. To test the possible ameliorative impact of CONPs on the toxic effect of cisplatin and oxaliplatin in male albino rats. Forty eight rats were divided into 6 groups: control group, CONPs group, cisplatin group, cisplatin and CONPs group, oxaliplatin group, and oxaliplatin and CONPs group. After 4 weeks, serum urea and creatinine, renal tissue level of interleukin 10 (IL10), and total antioxidant (TAO) were measured in control, CONPs, and cisplatin groups. The other kidney was used for histopathological and immunohistochemical studies. The right sciatic nerves and the lumbar spinal cord of rats from control, CONPs, and oxaliplatin groups were used for immunohistochemical evaluations of nitrotyrosine, myelin basic protein (MBP), and glial fibrillary acidic protein (GFAP). Cisplatin significantly increased serum urea and creatinine levels, significantly decreased the kidney level of IL10 and TAO with marked tubular necrosis, hemorrhage and renal damage. Also, it decreased IL10 immunohistochemical expression. CONPs significantly decreased the serum urea and creatinine level and increased IL10 and TAO with lower renal damage and strong IL10 expression compared with cisplatin group. Oxaliplatin significantly decreased MBP immunoreactivity and increased nitrotyrosine immunoreactivity. In the lumbar spinal cord, GFAP immunoreactivity was significantly increased. CONPs significantly increased MBP and decreased nitrotyrosine immunoreactivity. GFAP immunoreactivity was significantly decreased. CONPs ameliorated cisplatin and oxaliplatin primary toxicities through anti-inflammatory and antioxidant characteristics.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Cério/farmacologia , Cisplatino/toxicidade , Nanopartículas/administração & dosagem , Oxaliplatina/toxicidade , Animais , Antineoplásicos/toxicidade , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ratos , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Medula Espinal/patologia
6.
J Gastrointest Cancer ; 50(3): 485-492, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29681001

RESUMO

BACKGROUND: Fatty acid synthase (FAS) is a valuable lipid enzyme involved in lipid biosynthesis and suggested to contribute in tumor carcinogenesis. Vascular endothelial growth factor (VEGF) is considered a serious angiogenic growth factor in the angiogenic pathway which is a very important in tumor growth and metastasis. Thus, inhibition of lipid biosynthesis and tumor angiogenesis can be new goals for colorectal cancer (CRC) treatment. AIM OF THE WORK: The assessment of the expression of FAS and VEGF protein and the relationship between them in CRC with the clinicopathological parameters. METHODS: The present retrospective study included 63 paraffin blocks previously diagnosed as primary cases of CRC. The slides were subjected to FAS and VEGF immunohistochemical staining using a streptavidin-biotin-peroxidase. The relationships among FAS and VEGF expression and clinicopathological parameters were statistically analyzed. RESULTS: The expression rate of FAS was 81% and VEGF was 84.1% in the studied cases. FAS expression was significantly associated with histopathological type (p = 0.02) and grade (p = 0.04), and highly associated with lymph node metastasis and stage (p < 0.001).VEGF was significantly associated with histopathological type (p = 0.01) and tumor depth (p = 0.02); highly associated with grade, lymph node metastasis, and stage (p < 0.001). There was a positive association between FAS and VEGF expression in CRC (p < 0.001). CONCLUSION: FAS and VEGF showed a highly significant expression in the studied primary CRC cases. A significant association was observed between their expressions, suggesting the involvement of FAS in tumor angiogenesis. So they constitute potential targets in cancer prevention and treatment and make FAS an attractive antiangiogenic target.


Assuntos
Adenocarcinoma Mucinoso/secundário , Adenocarcinoma/secundário , Biomarcadores Tumorais/metabolismo , Carcinoma de Células em Anel de Sinete/secundário , Neoplasias Colorretais/patologia , Ácido Graxo Sintase Tipo I/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma Mucinoso/metabolismo , Adulto , Idoso , Carcinoma de Células em Anel de Sinete/metabolismo , Estudos de Casos e Controles , Neoplasias Colorretais/metabolismo , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica , Prognóstico , Estudos Retrospectivos
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