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1.
Lancet Oncol ; 22(3): 361-369, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33556324

RESUMO

BACKGROUND: Screening for breast cancer and cervical cancer in the newly independent states of the former Soviet Union is largely opportunistic, and countries in the region have among the highest cervical cancer incidence in the WHO European Region. We aimed to compare the stage-specific distributions and changes over time in breast cancer and cervical cancer incidence in the newly independent states of the former Soviet Union. METHODS: We collected breast cancer and cervical cancer incidence data from official statistics from Armenia, Azerbaijan, Belarus, Georgia, Kazakhstan, Kyrgyzstan, Republic of Moldova, Russian Federation, Ukraine, and Uzbekistan for the years 2008-17 by tumour, node, metastasis (TNM) stage, and by age where population-based cancer registry data were available. We used log-linear regression to quantify the changes over time in age-standardised rates. FINDINGS: During the period 2013-17, more than 50% of breast cancer cases across the analysed countries, and more than 75% of breast cancer cases in Belarus, Kazakhstan, and Ukraine, were registered at stages I-II. The proportion of stage I breast cancer cases was highest in the screening age group (50-69 years) compared with other ages in Moldova and the Russian registries, but was highest in those aged 15-49 years in Georgia and Ukraine. Breast cancer stage-specific incidence rates increased over time, most prominently for stage I cancers. For cervical cancer, the proportions of cancers diagnosed at a late stage (stages III and IV) were high, particularly in Moldova and Armenia (>50%). The proportion of stage I cervical cancer cases decreased with age in all countries, whereas the proportions of late stage cancers increased with age. Stage-specific incidence rates of cervical cancer generally increased over the period 2008-17. INTERPRETATION: Our results suggest modest progress in early detection of breast cancer in the newly independent states of the former Soviet Union. The high proportions of early-stage disease in the absence of mammography screening (eg, in Belarus) provide a benchmark for what is achievable with rapid diagnosis. For cervical cancer, there is a need to tackle the high burden and unfavourable stage-specific changes over time in the region. A radical shift in national policies away from opportunistic screening toward organised, population-based, quality-assured human papillomavirus vaccination and screening programmes is urgently needed. FUNDING: Union for International Cancer Control, WHO Regional Office for Europe, and Ministry of Health of Ukraine.


Assuntos
Neoplasias da Mama/patologia , Neoplasias do Colo do Útero/patologia , Adolescente , Adulto , Idoso , Neoplasias da Mama/classificação , Neoplasias da Mama/epidemiologia , Detecção Precoce de Câncer , Feminino , Seguimentos , Humanos , Incidência , Pessoa de Meia-Idade , Estadiamento de Neoplasias , U.R.S.S./epidemiologia , Neoplasias do Colo do Útero/classificação , Neoplasias do Colo do Útero/epidemiologia , Adulto Jovem
2.
Biomacromolecules ; 15(1): 327-38, 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24308459

RESUMO

Lignin nanotubes (LNTs) synthesized from the aromatic plant cell wall polymer lignin in a sacrificial alumina membrane template have as useful features their flexibility, ease of functionalization due to the availability of many functional groups, label-free detection by autofluorescence, and customizable optical properties. In this report we show that the physicochemical properties of LNTs can be varied over a wide range to match requirements for specific applications by using lignin with different subunit composition, a function of plant species and genotype, and by choosing the lignin isolation method (thioglycolic acid, phosphoric acid, sulfuric acid (Klason), sodium hydroxide lignin), which influences the size and reactivity of the lignin fragments. Cytotoxicity studies with human HeLa cells showed that concentrations of up to 90 mg/mL are tolerated, which is a 10-fold higher concentration than observed for single- or multiwalled carbon nanotubes (CNTs). Confocal microscopy imaging revealed that all LNT formulations enter HeLa cells without auxiliary agents and that LNTs made from NaOH-lignin penetrate the cell nucleus. We further show that DNA can adsorb to LNTs. Consequently, exposure of HeLa cells to LNTs coated with DNA encoding the green fluorescent protein (GFP) leads to transfection and expression of GFP. The highest transfection efficiency was obtained with LNTs made from NaOH-lignin due to a combination of high DNA binding capacity and DNA delivery directly into the nucleus. These combined features of LNTs make LNTs attractive as smart delivery vehicles of DNA without the cytotoxicity associated with CNTs or the immunogenicity of viral vectors.


Assuntos
Técnicas de Transferência de Genes , Lignina/química , Nanotubos/química , Extratos Vegetais/química , Células HeLa , Humanos , Lignina/administração & dosagem , Lignina/isolamento & purificação , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Caules de Planta
3.
Polymer (Guildf) ; 54(3): 1197-1207, 2013 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-23525522

RESUMO

The field of bone and cartilage tissue engineering has a pressing need for novel, biocompatible, biodegradable biocomposites comprising polymers with bioceramics or bioglasses to meet numerous requirements for these applications. We created hydrolytically degradable hydrogel/bioceramic biocomposites, comprising poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogels and 50 wt% biphasic hydroxyapatite/ß-tricalcium phosphate (60/40) through in situ polymerization. The hydrolytic degradation starts with hydrolysis of the cross-linker, N, O-dimethacryloyl hydroxylamine, which was synthesized in house. Swelling and degradation were examined in details at a phosphate buffered saline solution at 37 °C over a 12-week period of time. To vary degradability, a co-monomer, acrylic acid (AA) or 2-hydroxypropyl methacrylamide (HPMA), was introduced, coupled with altering the concentration of the cross-linker and of the bioceramic. The co-monomer HPMA was found to be more effective than AA in enhancing degradation, though AA led to greater swelling ratios. 33% of weight loss was achieved in some of the biocomposites containing HPMA. Porous structures were developed during swelling and degradation in biocomposites with AA but not in those containing HPMA, suggesting different degradation mechanisms: bulk erosion vs. bulk degradation. Good biocompatibility, as evidenced by attachment and proliferation of mouse-derived osteoblast precursor cells from the MC3T3-E1 lineage, was observed on these biomaterials, regardless of the type of the co-monomer. The rationale and approaches employed here open up new opportunities for creating novel, complex organic-inorganic biomaterials in orthopedic tissue engineering.

4.
J Cancer Policy ; 38: 100436, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37544479

RESUMO

BACKGROUND: Eastern Europe and Central Asia (EECA) countries have higher cervical and breast cancer mortality rates and later stage at diagnosis compared with the rest of WHO European Region. The aim was to explore current early detection practices including "dispensarization" for breast and cervix cancer in the region. METHODS: A questionnaire survey on early detection practices for breast and cervix cancer was sent to collaborators in 11 countries, differentiating services in the primary health setting, and population-based programs. Responses were received from Armenia, Belarus, Georgia, Kazakhstan, Kyrgyzstan, the Russian Federation (Arkhangelsk, Samara and Tomsk regions), Tajikistan, Ukraine, and Uzbekistan. RESULTS: All countries but Georgia, Kyrgyzstan, and the Russian Federation had opportunistic screening by clinical breast exam within "dispensarization" program. Mammography screening programs, commonly starting from age 40, were introduced or piloted in eight of nine countries, organized at national oncology or screening centres in Armenia, Belarus and Georgia, and within primary care in others. Six countries had "dispensarization" program for cervix cancer, mostly starting from the age 18, with smears stained either by Romanowsky-Giemsa alone (Belarus, Tajikistan and Ukraine), or alternating with Papanicolaou (Kazakhstan and the Russian Federation). In parallel, screening programs using Papanicolaou or HPV test were introduced in seven countries and organized within primary care. CONCLUSION: Our study documents that parallel screening systems for both breast and cervix cancers, as well as departures from evidence-based practices are widespread across the EECA. Within the framework of the WHO Initiatives, existing opportunistic screening should be replaced by population-based programs that include quality assurance and control.


Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos , Adulto , Adolescente , Neoplasias do Colo do Útero/diagnóstico , Detecção Precoce de Câncer , Europa Oriental/epidemiologia , Ásia Central/epidemiologia , Federação Russa
5.
Asian Pac J Cancer Prev ; 24(12): 4227-4235, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38156858

RESUMO

BACKGROUND: In 2021, a survey was conducted as part of the regional program of the United Nations Population Fund (UNFPA) Regional Office for Eastern Europe and Central Asia (EECA) to assess the policies and practices relating to HPV vaccination and cervical cancer screening in the 17 countries and territories included in this region. Since then, very substantial progress has been made with HPV vaccination across the region so another survey was conducted establish the current situation. METHODS: A 10 question survey covering the policies, plans and practices for HPV vaccination was prepared. As cervical cancer prevention is a priority for the UNFPA, its offices in the 17 countries and territories included in this study are well placed to identify the people who can provide authoritative data for this survey. Working with the UNFPA offices, the questionnaires were sent to these national experts in May 2023, with data collected until 30 June 2023. All countries and territories returned completed questionnaires. RESULTS: In the period from 30 June 2021 to 30 June 2023, the number of countries and territories that have implemented or are implementing HPV vaccination programs has doubled. As of 30 June 2021, only 6 of 17 countries and territories had implemented national HPV vaccination programmes, and by 30 June 2023, another 6 could be added to this list. Of the 4 countries with sub-optimal vaccination coverage rates in 2021, none showed substantial improvement over the 2-year period. CONCLUSIONS: The implementation of HPV vaccination programs across the region is progressing very rapidly with ≈70% of the countries and territories implementing or having implemented national programs. However, greater attention needs to be given to ensuring that both the old and the new programs will achieve high coverage rates.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/diagnóstico , Detecção Precoce de Câncer , Ásia/epidemiologia , Políticas , Vacinação , Vacinas contra Papillomavirus/uso terapêutico
6.
Asian Pac J Cancer Prev ; 24(5): 1781-1788, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37247301

RESUMO

BACKGROUND: To assess readiness to achieve the WHO Global Strategy targets for HPV vaccination and cervical screening and to guide capacity building, the current status of these services in 18 Eastern European and Central Asian countries, territories and entities (CTEs) was evaluated. METHODS: In order to assess the current status of HPV vaccination and cervical cancer screening in these 18 CTEs, a 30 question survey tool was developed, covering: national policies, strategies and plans for cervical cancer prevention; status of cancer registration; status of HPV vaccination; and current practices for cervical cancer screening and treatment of precancerous lesions. As cervical cancer prevention comes within the mandate of the United Nations Fund for Population Development (UNFPA), the UNFPA offices in the 18 CTEs have regular contact with national experts who are directly involved in cervical cancer prevention actions and are well placed to provide the data required for this survey. Working through the UNFPA offices, the questionnaires were sent to these national experts in April 2021, with data collected from April to July 2021. All CTEs returned completed questionnaires. RESULTS: Only Armenia, Georgia, Moldova, North Macedonia, Turkmenistan and Uzbekistan have implemented national HPV vaccination programmes, with only the last 2 of these reaching the WHO target of 90% of girls fully vaccinated by age 15, while rates in the other 4 range from 8%-40%. Cervical screening is available in all CTEs but only Belarus and Turkmenistan have reached the WHO target of 70% of women screened once by age 35 and again by age 45, while rates elsewhere range from 2%-66%. Only Albania and Turkey follow the WHO recommendation to use a high-performance screening test, while the majority use cervical cytology as the main screening test and Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan use visual inspection. No CTEs currently operate systems to coordinate, monitor and quality assure (QA) the entire cervical screening process. CONCLUSIONS: Cervical cancer prevention services in this region are very limited. Achieving the WHO Global Strategy targets by 2030 will require substantial investments in capacity building by international development organisations.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Adolescente , Adulto , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Detecção Precoce de Câncer , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/prevenção & controle , Infecções por Papillomavirus/epidemiologia , Europa Oriental/epidemiologia , Programas de Rastreamento , Políticas , Ásia/epidemiologia , Vacinação , Vacinas contra Papillomavirus/uso terapêutico
7.
Carbohydr Polym ; 92(1): 206-13, 2013 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-23218284

RESUMO

In this study a unidirectionally aligned cellulose nanowhisker (CNW) composite was developed. CNW in poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) matrix was aligned using an external electric field and the morphology and mechanical properties of the resultant anisotropic composites were studied. PHBV films with 1.5-7 wt% of CNWs were manufactured using solution casting. A DC electric field of 56.25 kV/m was applied during solvent evaporation. Both microstructural and mechanical analyses were performed to study the orientation of CNWs in the films. Mechanical properties of the samples were tested at 0°, 15°, 30°, 45° and 90° with respect to electric field direction by a dynamic mechanical analyzer (DMA). DMA results showed that CNW concentration has a strong influence on the degree of CNW alignment. The electric field was effective in aligning CNWs up to 4 wt% CNW concentration. The samples with higher concentrations showed virtually isotropic behavior, due to significantly enhanced restraints on CNW mobility. The restrains were attributed to CNW/CNW and CNW/polymer interactions. Rheological results confirmed the enhance restraints.


Assuntos
Celulose , Nanocompostos/química , Poliésteres , Anisotropia , Celulose/síntese química , Celulose/química , Fenômenos Mecânicos , Poliésteres/síntese química , Poliésteres/química , Reologia/métodos , Resistência à Tração
8.
Carbohydr Polym ; 90(1): 541-50, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24751075

RESUMO

In this study, biodegradable poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) films with 1.2-4.6 wt% of cellulose nanowhiskers (CNWs) were manufactured by solution casting using N,N-dimethylformide (DMF) as the solvent. Crystallization behaviors of PHBV/CNW composites were studied under isothermal conditions using differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The changes in PHBV crystalline structure were studied using wide angle X-ray diffraction (WAXD). Avrami analysis was performed to study the effects of CNW concentration and temperature on the crystallization rate and crystallinity of PHBV. POM study confirmed the results from the Avrami analysis. In particular, the results revealed the dual effects (i.e., nucleation and confinement) of CNWs on PHBV nucleation. Depending on the concentration of CNWs, the crystallization rate of PHBV could be either increased or decreased due to the combined effects. High crystallization temperatures increased the diffusion rate of PHBV chains and the growth rate of PHBV spherulites. However, the nucleation effect of CNWs decreased at high crystallization temperatures.


Assuntos
Celulose/química , Nanofibras/química , Poliésteres/química , Cristalização , Teste de Materiais/métodos , Difração de Raios X/métodos
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