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1.
Cancers (Basel) ; 14(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36291796

RESUMO

Background. In many malignancies, sentinel lymph node dissection (SLND) is being used as a nodal staging tool. We prospectively evaluated the diagnostic value of radio-guided sentinel lymph node (SLN) detection in patients with prostate cancer (PCa). This study aimed to investigate the reliability of the radio-guided SLN detection technique for perioperative localization of LNs metastases as well as to map lymphatic drainage patterns of the prostate. Methods. Forty-three patients with intermediate- or high-risk cN0cM0 PCa at conventional imaging underwent radical prostatectomy with modified-extended pelvic lymph node dissection (mePLND). A day before the planned surgery, a Tc-99m nanocolloid was injected into the prostate under the control of transrectal ultrasonography (TRUS). Preoperative single-photon emission computed tomography (SPECT-CT) imaging and intraoperative gamma-probe were used to identify SLNs. All positive lesions were excised, followed by mePLND. The excised lymph nodes (LNs) were then submitted for histopathological examination, which was used as a reference for the calculation of diagnostic parameters of the SLN technique for SPECT-CT and the intraoperative gamma-probe. Results. In total, 119 SLNs were detected preoperatively (SPECT-CT) and 118 intraoperatively (gamma-probe). The study revealed that both SLN detection techniques showed a sensitivity of 90% and a specificity of 6.06%. The negative predictive value (NPV) was 66.67%. SLN technique would have correctly staged nine of 10 patients, which is the same result as in the case of limited LND. However, it allowed the removal of all metastatic nodes only in four of them. SLND would have comprised 69.7% of preoperatively detected LNs, and removed 13 out of 19 positive LNs (68.42%), respectively. Conclusions. Radio-guided SLND has a low diagnostic rate and is a poor staging tool. ePLND remains the gold standard in nodal metastases assessment in PCa. Our study indicates that lymphatic drainage of the prostate and actual metastasis routes may vary significantly.

2.
J Org Chem ; 87(9): 5904-5915, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35388702

RESUMO

An efficient method for the preparation of arylnaphthalene lignans (ANLs) was developed, which is based on the Photo-Dehydro-Diels-Alder (PDDA) reaction. While intermolecular PDDA reactions turned out to be inefficient, the intramolecular variant using suberic acid as tether linking two aryl propiolic esters smoothly provided naphthalenophanes. The irradiations were performed with a previously developed annular continuous-flow reactor and UVB lamps. In this way, the natural products Alashinol D, Taiwanin C, and an unnamed ANL could be prepared.


Assuntos
Produtos Biológicos , Lignanas , Reação de Cicloadição , Ésteres , Naftalenos
3.
J Virol ; 92(2)2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29093092

RESUMO

Vaccinia virus is unusual among DNA viruses in replicating exclusively in the cytoplasm of infected cells. The single-stranded DNA (ssDNA) binding protein (SSB) I3 is among the replication machinery encoded by the 195-kb genome, although direct genetic analysis of I3 has been lacking. Herein, we describe a complementing cell line (CV1-I3) that fully supports the replication of a null virus (vΔI3) lacking the I3 open reading frame (ORF). In noncomplementing CV1-CAT cells, vΔI3 shows a severe defect in the production of infectious virus (≥200-fold reduction). Early protein synthesis and core disassembly occur normally. However, DNA replication is profoundly impaired (≤0.2% of wild-type [WT] levels), and late proteins do not accumulate. When several other noncomplementing cell lines are infected with vΔI3, the yield of infectious virus is also dramatically reduced (168- to 1,776-fold reduction). Surprisingly, the residual levels of DNA accumulation vary from 1 to 12% in the different cell lines (CV1-CAT < A549 < BSC40 < HeLa); however, any nascent DNA that can be detected is subgenomic in size. Although this subgenomic DNA supports late protein expression, it does not support the production of infectious virions. Electron microscopy (EM) analysis of vΔI3-infected BSC40 cells reveals that immature virions are abundant but no mature virions are observed. Aberrant virions characteristic of a block to genome encapsidation are seen instead. Finally, we demonstrate that a CV1 cell line encoding a previously described I3 variant with impaired ssDNA binding activity is unable to complement vΔI3. This report provides definitive evidence that the vaccinia virus I3 protein is the replicative SSB and is essential for productive viral replication.IMPORTANCE Poxviruses are of historical and contemporary importance as infectious agents, vaccines, and oncolytic therapeutics. The cytoplasmic replication of poxviruses is unique among DNA viruses of mammalian cells and necessitates that the double-stranded DNA (dsDNA) genome encode the viral replication machinery. This study focuses on the I3 protein. As a ssDNA binding protein (SSB), I3 has been presumed to play essential roles in genome replication, recombination, and repair, although genetic analysis has been lacking. Herein, we report the characterization of an I3 deletion virus. In the absence of I3 expression, DNA replication is severely compromised and viral yield profoundly decreased. The production of infectious virus can be restored in a cell line expressing WT I3 but not in a cell line expressing an I3 mutant that is defective in ssDNA binding activity. These data show conclusively that I3 is an essential viral protein and functions as the viral replicative SSB.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Deleção de Sequência , Vaccinia virus/fisiologia , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral , Linhagem Celular , Replicação do DNA , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/metabolismo , Expressão Gênica , Regulação Viral da Expressão Gênica , Teste de Complementação Genética , Humanos , Poxviridae/genética , Poxviridae/metabolismo , Vacínia/virologia , Vaccinia virus/ultraestrutura
4.
Cell Stem Cell ; 20(4): 478-489.e5, 2017 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-28388428

RESUMO

Efforts to identify pharmaceuticals to treat heritable metabolic liver diseases have been hampered by the lack of models. However, cells with hepatocyte characteristics can be produced from induced pluripotent stem cells (iPSCs). Here, we have used hepatocyte-like cells generated from homozygous familial hypercholesterolemia (hoFH) iPSCs to identify drugs that can potentially be repurposed to lower serum LDL-C. We found that cardiac glycosides reduce the production of apolipoprotein B (apoB) from human hepatocytes in culture and the serum of avatar mice harboring humanized livers. The drugs act by increasing the turnover of apoB protein. Analyses of patient medical records revealed that the treatment of patients with cardiac glycosides reduced serum LDL-C levels. These studies highlight the effectiveness of using iPSCs to screen for potential treatments for inborn errors of hepatic metabolism and suggest that cardiac glycosides could provide an approach for reducing hepatocyte production of apoB and treating hypercholesterolemia.


Assuntos
Glicosídeos Cardíacos/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Hepatócitos/citologia , Hipercolesterolemia/tratamento farmacológico , Células-Tronco Pluripotentes Induzidas/citologia , Animais , Apolipoproteínas B/metabolismo , Glicosídeos Cardíacos/farmacologia , LDL-Colesterol/sangue , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Homozigoto , Humanos , Hipercolesterolemia/sangue , Hipolipemiantes/química , Hipolipemiantes/farmacologia , Hipolipemiantes/uso terapêutico , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Proteólise/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/uso terapêutico
5.
Virus Res ; 234: 193-206, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28159613

RESUMO

Vaccinia virus is the prototypic poxvirus. The 192 kilobase double-stranded DNA viral genome encodes most if not all of the viral replication machinery. The vaccinia virus DNA polymerase is encoded by the E9L gene. Sequence analysis indicates that E9 is a member of the B family of replicative polymerases. The enzyme has both polymerase and 3'-5' exonuclease activities, both of which are essential to support viral replication. Genetic analysis of E9 has identified residues and motifs whose alteration can confer temperature-sensitivity, drug resistance (phosphonoacetic acid, aphidicolin, cytosine arabinsode, cidofovir) or altered fidelity. The polymerase is involved both in DNA replication and in recombination. Although inherently distributive, E9 gains processivity by interacting in a 1:1 stoichiometry with a heterodimer of the A20 and D4 proteins. A20 binds to both E9 and D4 and serves as a bridge within the holoenzyme. The A20/D4 heterodimer has been purified and can confer processivity on purified E9. The interaction of A20 with D4 is mediated by the N'-terminus of A20. The D4 protein is an enzymatically active uracil DNA glycosylase. The DNA-scanning activity of D4 is proposed to keep the holoenzyme tethered to the DNA template but allow polymerase translocation. The crystal structure of D4, alone and in complex with A201-50 and/or DNA has been solved. Screens for low molecular weight compounds that interrupt the A201-50/D4 interface have yielded hits that disrupt processive DNA synthesis in vitro and/or inhibit plaque formation. The observation that an active DNA repair enzyme is an integral part of the holoenzyme suggests that DNA replication and repair may be coupled.


Assuntos
DNA Viral/biossíntese , DNA Polimerase Dirigida por DNA/metabolismo , Multimerização Proteica , Uracila-DNA Glicosidase/metabolismo , Vaccinia virus/enzimologia , Proteínas Virais/metabolismo , DNA Polimerase Dirigida por DNA/química , Ligação Proteica , Recombinação Genética , Uracila-DNA Glicosidase/química , Proteínas Virais/química , Replicação Viral
6.
J Org Chem ; 81(19): 9147-9157, 2016 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-27618200

RESUMO

Naphthalenophanes are a special type of cyclophanes. While in the past (1,5)-, (1,6)-, and (1,8)naphthalenophanes were successfully prepared by using the photo-dehydro-Diels-Alder (DDA) reaction, access to (1,7)naphthalenophanes by this method was hitherto unknown. After numerous unsuccessful attempts to prepare these compounds by thermal DDA, we found that the photoinitiated variant (PDDA) represents a very efficient method to [k](1,7)naphthalenophanes 13. The scope ranged from highly strained (k = 11, 12) to macrocyclic products (k = 22, 24). The extraordinary reactivity could be explained by folded ground-state geometries of diketones 12 used as reactants of the PDDA. Furthermore, we calculated the ring-strain energies with the help of an isodesmic reaction and evaluated structural and spectroscopic (NMR) consequences of ring strain.

7.
Ginekol Pol ; 73(4): 342-5, 2002 Apr.
Artigo em Polonês | MEDLINE | ID: mdl-12152281

RESUMO

OBJECTIVE: The clinical characteristics of pregnancy complicated by ovarian tumors were investigated. MATERIAL AND METHODS: A review was performed of patients who were seen with ovarian tumors in pregnancy from January 1985 to August 2000. We included patients with simple or complex tumors > 5 cm that were seen on ultrasonographic evaluation. RESULTS: 23 patients of 21,506 deliveries were identified with ovarian tumors that met the criteria. 21 had operative intervention, whereas 2 were managed conservatively. Gestational ages at the time of surgery ranged from 16 to 24 weeks. No intraoperative et postoperative maternal or fetal complications occurred. In 2 cases adnexal masses seen on ultrasonography resolved spontaneously by 16 weeks. 19 ovarian tumors were benign. One patient had a stage III ovarian carcinoma and went to total hysterectomy, and other patient had a stage IA ovarian carcinoma and went to simple adnexectomy. CONCLUSIONS: Ovarian surgery in pregnancy for persistent masses is important to obtain a final histologic diagnosis. Optimal gestational age for the surgery is among 16 and 24 weeks.


Assuntos
Neoplasias Ovarianas , Complicações Neoplásicas na Gravidez , Adulto , Feminino , Idade Gestacional , Humanos , Complicações do Trabalho de Parto/cirurgia , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/cirurgia , Polônia/epidemiologia , Gravidez , Complicações Neoplásicas na Gravidez/diagnóstico por imagem , Complicações Neoplásicas na Gravidez/epidemiologia , Complicações Neoplásicas na Gravidez/cirurgia , Resultado da Gravidez , Estudos Retrospectivos , Ultrassonografia
8.
Wiad Lek ; 55(9-10): 626-9, 2002.
Artigo em Polonês | MEDLINE | ID: mdl-12607419

RESUMO

Authors presented two different cases of ovarian cancer during pregnancy. The first case in the stage IA had favourable course. We performed ovariectomy in the second trimester. At the term of delivery cesarean section with total hysterectomy and omentectomy with following chemotherapy (PC) were carried out. The second case (IIIC stage) had a poor course and diagnosis (Cystadenocarcinoma papillary GIII). The management comprised of total hysterectomy and omentectomy with following chemotherapy (PAC + Bleomycin + Mitomycin). Despite our treatment the development of cancer was observed. The patient died after 8 months since operation. Early diagnosis and lower stage of cancer give better prognosis, however, clinical management is still discussed.


Assuntos
Cistadenoma Papilar , Neoplasias Ovarianas , Complicações Neoplásicas na Gravidez , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Cistadenoma Papilar/tratamento farmacológico , Cistadenoma Papilar/patologia , Cistadenoma Papilar/cirurgia , Feminino , Humanos , Histerectomia , Estadiamento de Neoplasias , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Ovariectomia , Gravidez , Complicações Neoplásicas na Gravidez/tratamento farmacológico , Complicações Neoplásicas na Gravidez/patologia , Complicações Neoplásicas na Gravidez/cirurgia , Fatores de Tempo
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