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1.
Front Public Health ; 11: 1148283, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37397723

RESUMO

Introduction: Chronic exposure to arsenic through drinking water has been linked to several cancers. The metabolism of arsenic is thought to play a key role in arsenic-related carcinogenesis as metabolites of varying toxicity are produced and either stored in or excreted from the body. Atlantic Canada has the highest age-standardized incidence rates of all cancers in the country. This may be due to its high levels of environmental arsenic and the prevalence of unregulated private wells for water consumption. Here, we aimed to characterize the profiles of arsenic species and metallome in the toenails of four cancer groups, compare them to healthy participants (N = 338), and assess potential associations between the profiles with cancer prevalence. Methods: This study employed a case-control design. Toenail samples and questionnaire data from cases (breast, cervical, prostate, and skin cancers) and controls were sourced from the Atlantic Partnership for Tomorrow's Health (PATH) cohort study. The levels of arsenic species were measured using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) paired with High Performance Liquid Chromatography (HPLC) and total concentrations of metallome (23 metals) were determined by ICP-MS separately. Multivariate analyses were conducted to compare cases with controls within each cancer group. Results: Arsenic speciation profiles varied by cancer type and were significantly different between cases and controls in the breast (p = 0.0330), cervical (p = 0.0228), and skin (p = 0.0228) cancer groups. In addition, the profiles of metallome (nine metals) were significantly differentiated in the prostate (p = 0.0244) and skin (p = 0.0321) cancer groups, with higher zinc concentrations among cases compared to controls. Conclusion: History of cancer diagnosis was associated with specific profiles of arsenic species and metallome. Our results indicate that arsenic methylation and zinc levels, as measured in toenails, may be an important biomarker for cancer prevalence. Further research is needed to use toenails as a prognostic measure of arsenic-and other metal-induced cancer.


Assuntos
Arsênio , Água Potável , Unhas , Arsênio/toxicidade , Estudos de Casos e Controles , Estudos de Coortes , Unhas/química , Exposição Ambiental , Neoplasias/induzido quimicamente , Neoplasias/epidemiologia , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Canadá/epidemiologia
2.
Hernia ; 27(1): 157-172, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36066755

RESUMO

PURPOSE: To realize a systematic review to evaluate groin hernia surgery for adults in sub-Saharan Africa. METHODS: We conducted a systematic review and meta-analysis, the primary objective of which was to determine the surgical techniques used for unilateral groin hernia surgery in sub-Saharan Africa. Studies published in the last 20 years were considered. A meta-analysis estimated the pooled prevalence with 95% confidence interval (CI) of mortality, chronic pain and recurrence. A subgroup analysis compared the rate of complications between complicated or uncomplicated hernia. RESULTS: We included 113 articles. The most used technique was Bassini in 40.1%, followed by Lichtenstein in 29.9% and Shouldice in 12.6%. The overall mortality rate was 0.6% (95% CI 0.4-0.9). The pooled recurrence rate was 1.4% (95% CI 1.05-1.9). The pooled rate of chronic pain was 2.7% (95% CI 1.9-3.7). We found that mortality rate for complicated hernias (6.4%) was higher compared to uncomplicated hernias (0.2%). This difference was statistically significant [p ≤ 0.001; OR = 47.7; 95 CI (27.2-83.47)]. CONCLUSION: This review showed that pure tissue repairs are the most used techniques with Bassini and Shouldice as leading procedures. The post-operative rates of recurrence and chronic pain are low. However, there is a high heterogeneity between studies than can underestimate these pooled prevalences. The consultation at complication stage remains frequent and associated with a higher mortality. Futures studies should focus on improving the quality of studies in terms of design and follow-up to increase the degree of evidence.


Assuntos
Dor Crônica , Hérnia Inguinal , Humanos , Adulto , Virilha/cirurgia , Herniorrafia/efeitos adversos , Herniorrafia/métodos , Dor Crônica/cirurgia , Hérnia Inguinal/cirurgia , Hérnia Inguinal/epidemiologia , África Subsaariana/epidemiologia , Recidiva , Telas Cirúrgicas
3.
Front Public Health ; 10: 818069, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35875010

RESUMO

Chronic exposure to inorganic arsenic and trace metals has been linked to prostate cancer, and altered arsenic methylation capacity may have an important role in arsenic carcinogenesis. Biomarkers may be able to elucidate this role. Our objectives were to characterize profiles of arsenic species and metallome in toenails and urine samples, compare profiles between prostate cancer cases and controls, and determine the discriminant ability of toenail and urine biomarkers. Toenail samples (n = 576), urine samples (n = 152), and questionnaire data were sourced from the Atlantic Partnership for Tomorrow's Health (PATH) cohort study. Healthy controls were matched to prostate cancer cases (3:1 ratio) on sex, age, smoking status, and the province of residence. Metallome profiles and proportions of arsenic species were measured in toenail and urine samples. Analysis of covariance (ANCOVA) was used to compare the mean percent monomethylarsonic acid (%MMA), dimethylarsonic acid (%DMA), inorganic arsenic (%iAs), primary methylation index (PMI, MMA/iAs), and secondary methylation index (SMI, DMA/MMA). Multivariate analysis of covariance (MANCOVA) was used to compare selected metal concentrations. Mean %MMA was significantly lower and SMI was significantly higher in toenails from prostate cancer cases compared to controls in unadjusted and adjusted models. Proportions of arsenic species were correlated with total arsenic in toenails. Arsenic speciation in urine was not different between cases and controls, nor were metallome profiles in toenails and urine. Our results indicate that toenails are a viable biomarker for altered arsenic speciation in prostate cancer cases and may have greater utility than urine in this context.


Assuntos
Arsênio , Neoplasias da Próstata , Arsênio/urina , Biomarcadores , Estudos de Coortes , Humanos , Masculino , Unhas , Neoplasias da Próstata/diagnóstico
4.
Front Chem ; 8: 260, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32391314

RESUMO

Peptoids, N-substituted glycine oligomers, are a class of diverse and sequence-specific peptidomimetics with wide-ranging applications. Advancing the functional repertoire of peptoids to emulate native peptide and protein functions requires engineering peptoids that adopt regular secondary and tertiary structures. An understanding of how changes to peptoid sequence change structural features, particularly in water-soluble systems, is underdeveloped. To address this knowledge gap, five 15-residue water-soluble peptoids that include naphthalene-functionalized side chains were designed, prepared, and subjected to a structural study using a palette of techniques. Peptoid sequence designs were based on a putative amphiphilic helix peptoid bearing structure-promoting (S)-N-(1-naphthylethyl)glycine residues whose self-association in water has been studied previously. New peptoid variants reported here include sequence changes that influenced peptoid conformational flexibility, functional group patterning (amphiphilicity), and hydrophobicity. Peptoid structures were evaluated and compared using circular dichroism spectroscopy, fluorescence spectroscopy, and size exclusion chromatography. Spectral data confirmed that sequence changes alter peptoids' degree of assembly and the organization of self-assembled structures in aqueous solutions. Insights gained in these studies will inform the design of new water-soluble peptoids with regular structural features, including desirable higher-order (tertiary and quaternary) structural features.

5.
J Phys Chem B ; 123(27): 5822-5831, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31251622

RESUMO

In this study, we provide a quantitative description of the adsorption of water-soluble N-substituted glycine oligomers (peptoids) to supported lipid bilayers that mimic mammalian plasma membranes. We prepared a small array of systematically varied peptoid sequences ranging in length from 3 to 15 residues. Using the nonlinear optical method second harmonic generation (SHG), we directly monitored adsorption of aqueous solutions of 3- and 15-residue peptoids to phospholipid membranes of varying physical phase, cholesterol content, and head group charge in physiologically relevant pH buffer conditions without the use of extrinsic labels. Equilibrium binding constants and relative surface coverages of adsorbed peptoids were determined from fits to the Langmuir model. Three- and 15-residue peptoids did not interact with cholesterol-containing lipids or charged lipids in the same manner, suggesting that a peptoid's adsorption mechanism changes with sequence length. In a comparison of four three-residue peptoids, we observed a correlation between equilibrium binding constants and calculated log D7.4 values. Cationic charge modulated surface coverage. Principles governing how peptoid sequence and membrane composition alter peptoid-lipid interactions may be extended to predict physiological effects of peptoids used as therapeutics or as coatings in medical devices.


Assuntos
Peptoides/química , Fosfolipídeos/química , Água/química , Sítios de Ligação , Concentração de Íons de Hidrogênio , Estrutura Molecular , Solubilidade
6.
Biopolymers ; 110(4): e23256, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30633339

RESUMO

Peptoids are versatile peptidomimetic molecules with wide-ranging applications from drug discovery to materials science. An understanding of peptoid sequence features that contribute to both their three-dimensional structures and their interactions with lipids will expand functions of peptoids in varied fields. Furthermore, these topics capture the enthusiasm of undergraduate students who prepare and study diverse peptoids in laboratory coursework and/or in faculty led research. Here, we present the synthesis and study of 21 peptoids with varied functionality, including 19 tripeptoids and 2 longer oligomers. We observed differences in fluorescence spectral features for 10 of the tripeptoids that correlated with peptoid flexibility and relative positioning of chromophores. Interactions of representative peptoids with sonicated glycerophospholipid vesicles were also evaluated using fluorescence spectroscopy. We observed evidence of conformational changes effected by lipids for select peptoids. We also summarize our experiences engaging students in peptoid-based projects to advance both research and undergraduate educational objectives in parallel.


Assuntos
Glicerofosfolipídeos/química , Peptoides/química , Concentração de Íons de Hidrogênio , Conformação Molecular , Peptoides/síntese química , Peptoides/isolamento & purificação , Espectrometria de Fluorescência
7.
Biopolymers ; 110(4): e23248, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30578630

RESUMO

A desire to replicate the structural and functional complexity of proteins with structured, sequence-specific oligomers motivates study of the structural features of water-soluble peptoids (N-substituted glycine oligomers). Understanding the molecular-level details of peptoid self-assembly in water is essential to advance peptoids' application as novel materials. Peptoid 1, an amphiphilic, putatively helical peptoid previously studied in our laboratory, shows evidence of self-association in aqueous solution. In this work, we evaluate how changes to aqueous solution conditions influence the self-association of 1. We report that changes to pH influence the fluorescence and CD spectroscopic features as well as the peptoid's interaction with a solvatochromic fluorophore and its apparent size as estimated by size exclusion chromatography. Addition of guanidine hydrochloride and ammonium sulfate also modulate spectroscopic features of the peptoid, its interaction with a solvatochromic fluorophore, and its elution in size exclusion chromatography. These data suggest that the ordering of the self-assembly changes in response to pH and with solvent additives and is more ordered at higher pH and in the presence of guanidine hydrochloride. The deeper understanding of the self-association of 1 afforded by these studies informs the design of new stimuli-responsive peptoids with stable tertiary or quaternary structures.


Assuntos
Peptoides/química , Água/química , Dicroísmo Circular , Concentração de Íons de Hidrogênio , Solubilidade , Solventes/química , Espectrometria de Fluorescência
8.
Breast Cancer Res Treat ; 165(2): 261-271, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28578507

RESUMO

PURPOSE: To report our experience with full-dose 21 Gy IORT in early breast cancer patients after breast-conserving surgery to define most important selection factors. METHODS: Seven hundred and fifty eight patients, subjected to conserving surgery and IORT, were retrospectively analyzed evaluating most important clinical outcomes. RESULTS: Median follow up was 5.2 years. Results from Cox analyses defined 2 groups of patients, "suitable" (age > 50 years, non lobular histology, tumour size ≤ 2 cm, pN0 or pNmic, ki67 ≤ 20%, non triple negative receptor status and G1-G2) and "unsuitable" for IORT, with a higher rate of breast related events moving from "suitable" to "unsuitable" group. The 5 year rate of IBR is 1.8% in suitable group with significant differences versus unsuitable (1.8 vs. 11.6%, p < 0.005). Same differences between two groups were evidenced in true local relapse (0.6 vs. 6.9%, p < 0.005) and in new ipsilateral BC (1.1 vs. 4.7%, p < 0.015). CONCLUSIONS: In our current practice we consider the following preoperative factors to select patients suitable for IORT: age > 50 years, absence of lobular histology, tumor size ≤ 2 cm, pN0 or pNmic, according to APBI consensus statement, including also ki67 ≤ 20%, non triple negative receptor status and G1-G2.


Assuntos
Neoplasias da Mama/radioterapia , Elétrons , Cuidados Intraoperatórios , Radioterapia/métodos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/cirurgia , Terapia Combinada , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Gradação de Tumores , Estadiamento de Neoplasias , Cuidados Pré-Operatórios , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Carga Tumoral
11.
Tumori ; 85(2): 143-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10363084

RESUMO

PURPOSE: With the aim of establishing clinical and technical criteria to homogenize radiotherapy practice, a working group of AIRO-Lombardia (Associazione Italiana di Radioterapia Oncologica--Gruppo regionale della Lombardia) has tried to define minimal requirements for radical and postoperative irradiation in prostate cancer. The document has been structured in such a way as to be also of interest to the urological and medical oncology communities. METHODS: The working group, composed of representatives of most of the regional radiotherapy departments in the Lombardy region, had monthly meetings during 1996 and 1997. The document on minimal requirements has been derived from the participants' combined experience and knowledge, from review of the literature, and from a 1995 regional survey on current practice of prostate irradiation. RESULTS: Minimal requirements for radical and postoperative irradiation of prostate cancer have been defined with respect to treatment strategies, pre-treatment diagnostic evaluation and staging, treatment prescription, preparation and execution, and quality assurance procedures. CONCLUSION: Standards of reference for minimal requirements in prostate cancer irradiation adapted to the regional structures and resources have been defined.


Assuntos
Neoplasias da Próstata/radioterapia , Humanos , Itália , Masculino , Estadiamento de Neoplasias , Neoplasias da Próstata/patologia , Radioterapia/normas , Dosagem Radioterapêutica
12.
Tumori ; 84(2): 252-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9620254

RESUMO

This paper describes the mechanisms of action of ionizing radiations combined with antineoplastic drugs. Some relevant drugs for the combined modality treatments of locally advanced lung cancer are reported. The meta-analyses including randomized trials comparing single agent (radiotherapy or chemotherapy) versus combined chemotherapy and radiotherapy in patients with unresectable non small cell lung cancer and limited small cell lung cancer are then reviewed. The clinical outcome in relation to different schedules of chemoradiotherapy (sequential, alternating and concurrent) is also focussed.


Assuntos
Neoplasias Esofágicas/terapia , Quimioterapia Adjuvante , Ensaios Clínicos como Assunto , Terapia Combinada , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/cirurgia , Humanos , Radiobiologia , Radioterapia Adjuvante , Fatores de Tempo , Resultado do Tratamento
13.
Radiol Med ; 81(6): 902-5, 1991 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-1650012

RESUMO

From January 1980 to December 1989, 86 patients with limited small cell lung carcinoma (SCLC) were treated in our Institution. Sixty-eight of them were males, 18 females; mean age was 58 years (range: 40-74); Karnofsky index was 80 or higher. All patients received induction multiagent chemotherapy (CAV or CAVE), usually fractionated into 3/4 cycles. Radiotherapy was administered by means of a 10 MV Linear Accelerator, 2-3 Gy/day, 5 days/week. Radiation dose was 60 Gy for 39 patients, 50 Gy for 25 patients, and 30 Gy for 22 patients. Parallel opposed fields (AP and PA) were used for administering the 30-Gy dose, while higher doses were delivered by multiportal arrangement (3/4 fields). Overall survival (corrected Kaplan-Meier) was 21.3% and 13.4% at 2 and 3 years, respectively; 2 years' survival according to dose was 24.5% for 60 Gy, 19.9% and 11% for 50 and 30 Gy, respectively. Mean survival time (MST) was 14 months for 60 Gy, 13 months and 10 months, respectively, for 50 and 30 Gy. Survival and disease-free survival rates were similar in patients who received 50 and 60 Gy. No major complications related to irradiation were observed, not even in the group receiving the highest dose. Our data are similar to those reported in the literature.


Assuntos
Carcinoma de Células Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Neoplasias Encefálicas/prevenção & controle , Neoplasias Encefálicas/secundário , Carcinoma de Células Pequenas/mortalidade , Carcinoma de Células Pequenas/secundário , Terapia Combinada , Hospitais , Humanos , Itália , Neoplasias Pulmonares/mortalidade , Dosagem Radioterapêutica , Taxa de Sobrevida
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