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1.
EMBO Rep ; 24(7): e55338, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37166011

RESUMO

The bacterial toxin CcdB (Controller of Cell death or division B) targets DNA Gyrase, an essential bacterial topoisomerase, which is also the molecular target for fluoroquinolones. Here, we present a short cell-penetrating 24-mer peptide, CP1-WT, derived from the Gyrase-binding region of CcdB and examine its effect on growth of Escherichia coli, Salmonella Typhimurium, Staphylococcus aureus and a carbapenem- and tigecycline-resistant strain of Acinetobacter baumannii in both axenic cultures and mouse models of infection. The CP1-WT peptide shows significant improvement over ciprofloxacin in terms of its in vivo therapeutic efficacy in treating established infections of S. Typhimurium, S. aureus and A. baumannii. The molecular mechanism likely involves inhibition of Gyrase or Topoisomerase IV, depending on the strain used. The study validates the CcdB binding site on bacterial DNA Gyrase as a viable and alternative target to the fluoroquinolone binding site.


Assuntos
Antibacterianos , Staphylococcus aureus , Animais , Camundongos , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Antibacterianos/farmacologia , DNA Girase/química , DNA Girase/genética , DNA Girase/metabolismo , DNA Topoisomerase IV/genética , DNA Topoisomerase IV/metabolismo , DNA Topoisomerase IV/farmacologia , Peptídeos/farmacologia
2.
Nat Chem Biol ; 18(10): 1046-1055, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35654847

RESUMO

Protein tertiary structure mimetics are valuable tools to target large protein-protein interaction interfaces. Here, we demonstrate a strategy for designing dimeric helix-hairpin motifs from a previously reported three-helix-bundle miniprotein that targets the receptor-binding domain (RBD) of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). Through truncation of the third helix and optimization of the interhelical loop residues of the miniprotein, we developed a thermostable dimeric helix-hairpin. The dimeric four-helix bundle competes with the human angiotensin-converting enzyme 2 (ACE2) in binding to RBD with 2:2 stoichiometry. Cryogenic-electron microscopy revealed the formation of dimeric spike ectodomain trimer by the four-helix bundle, where all the three RBDs from either spike protein are attached head-to-head in an open conformation, revealing a novel mechanism for virus neutralization. The proteomimetic protects hamsters from high dose viral challenge with replicative SARS-CoV-2 viruses, demonstrating the promise of this class of peptides that inhibit protein-protein interaction through target dimerization.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Dimerização , Humanos , Peptídeos/metabolismo , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo
3.
Int J Gynecol Cancer ; 34(6): 886-897, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38561194

RESUMO

OBJECTIVE: To establish the feasibility and safety of robotic interval debulking surgery following the MIRRORS protocol (robot-assisted laparoscopic assessment prior to robotic or open surgery) in women with advanced-stage ovarian cancer. MIRRORS is the first of three planned trials: MIRRORS, MIRRORS-RCT (pilot), and MIRRORS-RCT. METHODS: The participants were patients with stage IIIc-IVb epithelial ovarian cancer undergoing neo-adjuvant chemotherapy, suitable for interval debulking surgery with a pelvic mass ≤8 cm. The intervention was robot-assisted laparoscopic assessment prior to robotic or open interval debulking surgery (MIRRORS protocol). The primary outcome was feasibility of recruitment, and the secondary outcomes were quality of life (EORTC QLQC30/OV28, HADS questionnaires), pain, surgical complications, complete cytoreduction rate (%), conversion to open surgery (%), and overall and progression-free survival at 1 year. RESULTS: Overall, 95.8% (23/24) of patients who were eligible were recruited. Median age was 68 years (range 53-83). All patients had high grade serous histology and were BRCA negative. In total, 56.5% were stage IV, 43.5% were stage III, 87.0% had a partial response, while 13.0% had stable disease by RECIST 1.1. Median peritoneal cancer index was 24 (range 6-38). Following MIRRORS protocol, 87.0% (20/23) underwent robotic interval debulking surgery, and 13.0% (3/23) had open surgery. All patients achieved R<1 (robotic R0=47.4%, open R0=0%). No patients had conversion to open. Median estimated blood loss was 50 mL for robotic (range 20-500 mL), 2026 mL for open (range 2000-2800 mL) (p=0.001). Median intensive care length of stay was 0 days for robotic (range 0-8) and 3 days (range 3-13) for MIRRORS Open (p=0.012). The median length of stay was 1.5 days for robotic (range 1-17), 6 days for open (range 5-41) (p=0.012). The time to chemotherapy was as follows 18.5 days for robotic (range 13-28), 25 days for open (range 22-28) (p=0.139). CONCLUSIONS: Robotic interval debulking surgery appears safe and feasible for experienced robotic surgeons in patients with a pelvic mass ≤8 cm. A randomized controlled trial (MIRRORS-RCT) will determine whether MIRRORS protocol has non-inferior survival (overall and progression-free) compared with open interval debulking surgery.


Assuntos
Procedimentos Cirúrgicos de Citorredução , Estudos de Viabilidade , Neoplasias Ovarianas , Procedimentos Cirúrgicos Robóticos , Humanos , Feminino , Procedimentos Cirúrgicos Robóticos/métodos , Pessoa de Meia-Idade , Idoso , Procedimentos Cirúrgicos de Citorredução/métodos , Estudos Prospectivos , Neoplasias Ovarianas/cirurgia , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/tratamento farmacológico , Idoso de 80 Anos ou mais , Estadiamento de Neoplasias , Carcinoma Epitelial do Ovário/cirurgia , Carcinoma Epitelial do Ovário/patologia , Carcinoma Epitelial do Ovário/tratamento farmacológico , Estudos de Coortes , Qualidade de Vida , Laparoscopia/métodos
4.
Int J Mol Sci ; 23(3)2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35163645

RESUMO

BACKGROUND: Recently, we have shown that seven genes, namely GBP5, IRS2, KRT4, LINCOO707, MRPL55, RRS1 and SLC4A11, have prognostic power for the overall survival in ovarian cancer (OC). METHODS: We present an analysis on the association of these genes with any phenotypes and mutations indicative of involvement in female cancers and predict the structural and functional consequences of those SNPS using in silico tools. RESULTS: These seven genes present with 976 SNPs/mutations that are associated with human cancers, out of which 284 related to female cancers. We have then analysed the mutation impact on amino acid polarity, charge and water affinity, leading to the identification of 30 mutations in gynaecological cancers where amino acid (aa) changes lead to opposite polarity, charges and water affinity. Out of these 30 mutations identified, only a missense mutation (i.e., R831C/R804C in uterine corpus endometrial carcinomas, UCEC) was suggestive of structural damage on the SLC4A11 protein. CONCLUSIONS: We demonstrate that the R831C/R804C mutation is deleterious and the predicted ΔΔG values suggest that the mutation reduces the stability of the protein. Future in vitro studies should provide further insight into the role of this transporter protein in UCEC.


Assuntos
Biomarcadores Tumorais/genética , Biologia Computacional/métodos , Neoplasias dos Genitais Femininos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Polimorfismo de Nucleotídeo Único , Prognóstico
5.
Angew Chem Int Ed Engl ; 60(47): 24870-24874, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34519402

RESUMO

Amino acid side chains are key to fine-tuning the microenvironment polarity in proteins composed of polar amide bonds. Here, we report that substituting an oxygen atom of the backbone amide bond with sulfur atom desolvates the thioamide bond, thereby increasing its lipophilicity. The impact of such local desolvation by O to S substitution in proteins was tested by synthesizing thioamidated variants of Pin1 WW domain. We observe that a thioamide acts in synergy with nonpolar amino acid side chains to reduce the microenvironment polarity and increase protein stability by more than 14 °C. Through favorable van der Waals and hydrogen bonding interactions, this single atom substitution significantly stabilizes proteins without altering the amino acid sequence and structure of the native protein.


Assuntos
Oxigênio/química , Peptídeos/química , Proteínas/química , Enxofre/química , Estabilidade Proteica
6.
J Pept Sci ; 26(4-5): e3248, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32202029

RESUMO

The unique physicochemical properties of a thioamide bond, which is an ideal isostere of an amide bond, have not been fully exploited because of the tedious synthesis of thionated amino acid building blocks. Here, we report a purification-free and highly efficient synthesis of thiobenzotriazolides of Fmoc-protected and orthogonally protected 20 naturally occurring amino acids including asparagine, glutamine, and histidine. The near-quantitative conversion to the respective thioamidated peptides on solid support demonstrates the robustness of the synthetic route. Furthermore, the unaltered incorporation efficiency of thiobenzotriazolides from their stock solution till 48 h suggests their compatibility toward automated peptide synthesis. Finally, utilizing an optimized cocktail of 2% DBU + 5% piperazine for fast Fmoc-deprotection, we report the synthesis of a thioamidated Pin1 WW domain and thioamidated GB1 directly on solid support.


Assuntos
Peptídeos/síntese química , Proteínas/síntese química , Tioamidas/síntese química , Estrutura Molecular , Peptídeos/química , Proteínas/química , Tioamidas/química
7.
Int J Gynecol Cancer ; 30(9): 1424-1433, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32576608

RESUMO

On March 11, 2020 the COVID-19 outbreak was declared a 'pandemic' by the World Health Organization. COVID-19 is associated with higher surgical morbidity and mortality. An array of guidelines on the management of cancer during this pandemic have been published since the first reports of the outbreak. This narrative review brings all the relevant information from the guidelines together into one document, to support patient care. We present a detailed review of published guidelines, statements, comments from peer-reviewed journals, and nationally/internationally recognized professional bodies and societies' web pages (in English or with English translation available) between December 1, 2019 and May 27, 2020. Search terms included combinations of COVID, SARS-COV-2, guideline, gynecology, oncology, gynecological, cancer. Recommendations for surgical and oncological prioritization of gynecological cancers are discussed and summarized. The role of minimally invasive surgery, patient perspectives, medico-legal aspects, and clinical trials during the pandemic are also discussed. The consensus is that elective benign surgery should cease and cancer surgery, chemotherapy, and radiotherapy should continue based on prioritization. Patient and staff face-to-face interactions should be limited, and health resources used efficiently using prioritization strategies. This review and the guidelines on which it is based support the difficult decisions currently facing us in gynecological cancer. It is a balancing act: limited resources and a hostile environment pitted against the time-sensitive nature of cancer treatment. We can only hope to do our best for our patients with the resources available to us.


Assuntos
Infecções por Coronavirus/prevenção & controle , Neoplasias dos Genitais Femininos/terapia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Guias de Prática Clínica como Assunto , Betacoronavirus , COVID-19 , Feminino , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos , Radioterapia , SARS-CoV-2 , Triagem
8.
Trop Anim Health Prod ; 52(6): 3899-3905, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32737663

RESUMO

Pomegranate fruit peel is a great source of natural polyphenols. The objective of the present study was to evaluate efficacy of pomegranate peel infusion (PPI) on growth characteristics, feed efficiency, blood metabolites and antioxidant profile of broiler chicken. A total of 200 broiler chickens were randomly assigned to 4 treatments with 5 replicates of 10 birds. Pomegranate peel infusion was supplemented in drinking water to 3 treatment groups in a graded dose. At the end of the trial (42 days), 2 broiler chickens from each pen were sampled for serum and liver tissue. Results revealed that low-dose (50 mL/L) PPI influenced (L: P < 0.001) final body weight, daily body weight gain, and feed conversion ratio. Quadratic effect (Q: P < 0.001) was found in overall body weight, average daily gain in body weight, and average daily feed intake. It was also observed that PPI had significant (L: P < 0.05) hypo-lipidaemic effect. PPI supplementation reduced (L: P < 0.01) lipid peroxidation in all supplemented birds. Reduced glutathione and catalase in the liver tissue was also increased linearly (L: P < 0.05) by PPI supplementation, suggesting that natural polyphenols present in the PPI can stimulate antioxidant defence system. Thus, it could be concluded that low-dose supplementation of pomegranate peel infusion could be of great benefits in broiler chickens as a source of natural antioxidants.


Assuntos
Antioxidantes/metabolismo , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Extratos Vegetais/metabolismo , Punica granatum/química , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Feminino , Frutas/química , Masculino , Extratos Vegetais/administração & dosagem , Distribuição Aleatória
9.
Acta Oncol ; 58(3): 342-352, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30614360

RESUMO

INTRODUCTION: Endometrial cancer is the most common gynaecological cancer and its incidence is rising due to increasing obesity rates. We are also seeing an increasing trend of young women diagnosed with either endometrial cancer or its precancerous state, endometrial hyperplasia. Diagnosis is dependent on invasive testing and there is no screening tool available for either general or high-risk population groups. Whilst vast amounts of research have been undertaken in higher-profile cancers such as ovarian and cervical, endometrial cancer is comparatively less investigated. AIM: In this literature review, we summarise the existing literature in understanding the role of tumour biomarkers for endometrial cancer and its preceding condition of endometrial hyperplasia. METHOD: NICE Healthcare Databases Search tool was used to search Embase, Medline and PubMed databases for relevant articles. CONCLUSION: There is currently no routinely used biomarker in endometrial cancer for diagnostic or prognostic purposes. Given the establishment of new genomic classifications of endometrial cancers, the use of biomarkers to drive therapeutic approaches will be the cornerstone for individualised cancer care in the coming decades.


Assuntos
Biomarcadores Tumorais/análise , Hiperplasia Endometrial/metabolismo , Neoplasias do Endométrio/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , DNA Tumoral Circulante/análise , Metilação de DNA , Hiperplasia Endometrial/genética , Neoplasias do Endométrio/genética , Feminino , Humanos , MicroRNAs , PTEN Fosfo-Hidrolase/genética , Proteínas/análise , Proteínas/metabolismo , Proteína Supressora de Tumor p53/genética
10.
Dermatology ; 235(4): 327-333, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31256169

RESUMO

BACKGROUND: The impact of lesion focality and centricity in relation to patient outcome and disease recurrence of vulvar intraepithelial neoplasia (VIN) is an understudied area of research, especially in immunocompromised women. The prevalence and incidence of VIN have increased steadily since the 1980s because of the co-existence of human papillomavirus (HPV) and human immunodeficiency virus (HIV). In this study, we retrospectively examined the records of VIN patients to determine the effect of lesion focality and centricity with respect to the interval to disease recurrence. MATERIALS AND METHODS: All women diagnosed with VIN and managed between January 2002 and December 2011 were included (n = 90) and followed up until December 2017. Symptoms at the time of presentation, including HIV positivity (n = 75), were collated, including the influences of multifocality and multicentricity on time to disease recurrence. RESULTS: Multicentricity caused a more rapid recurrence of disease than unicentricity (p = 0.006), whereas multifocality increased the risk of recurrence more than unifocality (p < 0.0001). Viral load in the HIV+ patients was not associated with time to disease recurrence, but the reduced number of CD4+ lymphocytes present in HIV+ patients was. Treatment modalities had no effect on disease recurrence. CONCLUSION: Both focality and centricity have effects on interval to recurrence and final patient outcome, with multifocal disease having a poorer prognosis. Centricity and focality should be recorded at the time of diagnosis and act as a warning for disease recurrence. HIV+ VIN patients with multifocal disease and/or known immunosuppression (low CD4+ lymphocyte counts) should be regarded as "high-risk" patients and treated accordingly.


Assuntos
Carcinoma in Situ/patologia , Infecções por HIV/imunologia , Neoplasias Vulvares/patologia , Carcinoma in Situ/imunologia , Progressão da Doença , Feminino , Humanos , Hospedeiro Imunocomprometido , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Neoplasias Vulvares/imunologia
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