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1.
Cancer Diagn Progn ; 2(6): 750-757, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36340465

RESUMO

BACKGROUND/AIM: The early diagnosis of breast cancer plays an important role in reducing mortality and optimizing the prognosis of the disease. The existing visual and histopathological methods do not give any information at a molecular level. Fourier transform infrared spectroscopy does not require any preparation, such as fixation and histological stains. The collected infrared spectral "biomarker bands" give information at a molecular level and could be used for biomarker screening, in order to minimize the false-positive or false-negative results. MATERIALS AND METHODS: For this prospective study, nine biopsies of lobular carcinoma (7 in situ and 2 invasive) and the adjacent healthy region of the biopsies were used. Each infrared spectrum consisted of 120 scans/spectrum (120 co-added spectra) at a spectral resolution of 4 cm -1 . RESULTS: The infrared spectral analysis revealed three important "diagnostic spectral regions" between 3,300-2,850 cm -1 , 1,700-1,500 cm -1 , and 850-800 cm -1 , which are related to membrane, collagen, and DNA configuration damage, respectively. The shift of the absorption band at 1,161 cm -1 at higher wave numbers up to 1,172 cm -1 is assigned to vC-O-C bonds due to membrane, protein, and DNA glycosylation. CONCLUSION: The "biomarker bands" at 1,172 cm -1 can be used as "diagnostic marker bands" for cancer progression. The shift of the absorbance band at 825 cm -1 of the native configuration of B-DNA to lower wavenumbers at 810 cm -1 Z-DNA in grade III, suggests the irreversible stage of the disease. The detection and possibility to differentiate the DNA structures may allow detection of carcinogenesis at the early stage of the disease, and development of new anticancer therapies.

2.
J Long Term Eff Med Implants ; 32(3): 57-63, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35993989

RESUMO

Fourier transform infrared spectroscopy was used to evaluate the molecular structure of bone tissues of patients who underwent revision of total hip and shoulder arthroplasty. The intensity increase of the spectral bands in the region of 3000-2850 cm-1 provided information about the increase of the lipophilic environment, which supported the formation of aggregates and amyloid protein formation. The appearance and the intensity increase of the "marker band" at 1744 cm-1 suggested protein peroxidation and inflammation progression. The shift of the amide I and amide II absorption bands from 1650 cm-1 and 1550 cm-1, respectively, to lower frequencies was related to changes of collagen conformation structure from α-helix to ß-sheet and random coil. The appearance and shifts of the new bands in the region 1200-900 cm-1 were related with the increasing of glycosylation upon inflammation. Important was also the disappearance of the hydroxyapatite vPO43- absorption bands at the spectral regions 1200-900 cm-1 and 550-650 cm-1 indicated the osteolysis development. Moreover, the formation of corrosive metallic implants confirmed the effect of oxidative stress on the development of periprosthetic joint infection.


Assuntos
Amidas , Sepse , Amidas/química , Osso e Ossos , Humanos , Inflamação , Estrutura Molecular , Estrutura Secundária de Proteína , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
3.
In Vivo ; 36(1): 189-197, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34972714

RESUMO

BACKGROUND/AIM: The pathogenesis, treatment and prevention of atherosclerosis continue to be the subject of intensive research and study by the scientific community. Based on Fourier-transform infrared spectra and 3D-Doppler echogram, we attempted to develop a computational simulation model for predicting the association of atherosclerotic risk factors with pathogenic molecular structural changes. MATERIALS AND METHODS: Atheromatic carotid arteries from 56 patients (60-85 years old) were used as samples. Color 3D-Doppler echogram screening was performed on all patients preoperatively. Each infrared spectrum consisted of 120 co-added spectra at a spectral resolution of 4 cm-1 Results: The infrared spectral analysis reveals 'marker bands', such as the 1,744 cm-1 band assigned to aldehyde formation and to the 'fingerprint' digital spectral region of 1,050-1,169 cm-1, characteristic of the presence of advanced glycation end products (C-O-C). The accumulation of calcium phosphate salts increases the formation rate of stenosis. The critical point of stenosis risk starts at about 45%, while when stenosis is over 60-70%, the risk of ischemic stroke or other major adverse cardiovascular events increases dramatically. CONCLUSION: Fourier-transform infrared spectroscopy and mathematical simulation models showed that carotid artery stenosis over 45% reduces the blood flow rate, while stenosis over 65% dramatically increases the hemodynamic disturbance, with a parallel increase the rate of ischemic stroke or other major adverse cardiovascular events.


Assuntos
Aterosclerose , Doenças das Artérias Carótidas , Estenose das Carótidas , Acidente Vascular Cerebral , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Espectroscopia de Infravermelho com Transformada de Fourier
4.
In Vivo ; 33(2): 567-572, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30804143

RESUMO

AIM: To investigate the molecular structural disorders of cancerous skin. MATERIALS AND METHODS: Human malignant melanoma and basal cell carcinoma biopsies were used for the investigation. Fourier transform infrared (FT-IR), Raman spectroscopy, and scanning electron microscopy were utilized. Spectral differences between healthy, basal cell carcinoma and melanoma tissues were recorded. RESULTS: The FT-IR bands of vasCH2, vsCH2 and Raman vsCH3 of cell membrane lipids were increased in intensity in melanoma due to an increased lipophilic environment. The FT-IR band at 1,744 cm-1 assigned to malondialdehyde can be used as a band diagnostic of cancer progression. The amide I bands at 1,654 cm-1 and 1,650 cm-1 for Raman and FT-IR, respectively were broader in spectra from melanoma, reflecting changes of protein secondary structure from α-helix to ß-sheet and random coil. The intensity of the FT-IR band at 1,046 cm-1 was increased in melanoma, suggesting glycosylation of the skin upon cancer development. Another band that might be considered as diagnostic was found at about 815 cm-1 in melanoma and was attributed to Z-DNA configuration. As far as we know, this is the first time that scanning electron microscopy revealed that metal components of titanium alloys from tooth implants were transferred to melanoma tissue taken from the back of one patient. CONCLUSION: Vibrational spectroscopy highlighted increased glycosylation in melanoma.


Assuntos
Carcinoma Basocelular/química , Melanoma/química , Proteínas de Neoplasias/química , Neoplasias Cutâneas/química , Idoso , Biópsia , Carcinoma Basocelular/patologia , Humanos , Malondialdeído/química , Melanoma/patologia , Pessoa de Meia-Idade , Estrutura Secundária de Proteína , Pele/química , Pele/patologia , Neoplasias Cutâneas/patologia , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Melanoma Maligno Cutâneo
5.
Mech Ageing Dev ; 172: 107-114, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29113732

RESUMO

FT-IR spectroscopy was used to investigate the effect of oxidative stress and to approach the mechanism on cancer bone demineralization, aortic valve mineralization and heterotopic ossification on disease development. The FT-IR spectra obtained from paediatric, adult bone and ex vivo irradiated adult healthy bone with a dose of 20Gy were compared with those of healthy bone. The increase of band intensity changes of vasCH2,vsCH2 in the region 3000-2850cm-1 depended on aging, the disease progression and the dose of irradiation. The bands at 3080cm-1 and 1744cm-1, which originate from olefinic terminal bond (v=CH) and ester carbonyl group (vROCO), respectively, indicate the influence of oxidative stress on lipid degradation and peroxidation, respectively. The new bands at about 1690cm-1 and 1516cm-1 denote the presence of ß-sheet conformation of the proteins due to the diseases, confirming the increasing amount of lipophilic environment and fibril formation. Comparison of the FT-IR spectra of calcified aortic valve and hip heterotopic ossification with that of normal bones showed that in the bone-like formation the peroxide anion free radicals play an important role in the disease.


Assuntos
Envelhecimento/metabolismo , Estenose da Valva Aórtica/metabolismo , Valva Aórtica/patologia , Neoplasias Ósseas/metabolismo , Calcinose/metabolismo , Cabeça do Fêmur/metabolismo , Ossificação Heterotópica/metabolismo , Estresse Oxidativo , Adulto , Envelhecimento/patologia , Valva Aórtica/metabolismo , Estenose da Valva Aórtica/patologia , Neoplasias Ósseas/patologia , Calcinose/patologia , Criança , Pré-Escolar , Feminino , Cabeça do Fêmur/patologia , Humanos , Masculino , Ossificação Heterotópica/patologia , Espectroscopia de Infravermelho com Transformada de Fourier
6.
In Vivo ; 31(6): 1131-1137, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29102935

RESUMO

BACKGROUND/AIM: Mid-infrared spectroscopy (4000-500 cm-1) was used to analyze the spectral changes and differences of the characteristic absorption bands of the skin components due to cancer development for early clinical diagnosis. MATERIALS AND METHODS: Human biopsies from basal cell carcinoma, malignant melanoma, and nevus were used, while normal skin tissue served as a control. RESULTS: The high quality of Fourier-transform infrared (FT-IR) spectra showed that upon cancer development the intensity of the absorption band at approximately 3062 cm-1 was increased, indicating that most of the proteins had the configuration of amide B and the ß-sheet protein structure predominated. The stretching vibration bands of vCH2 in the region 2950-2850 cm-1 were increased in melanoma and nevus, while were less pronounced in basal cell carcinoma due to the increased lipophilic environment. In addition, the intensity of a new band at 1744 cm-1, which is assigned to aldehyde, was increased in melanoma and nevus and appeared as a shoulder in the spectra of normal skin. The absorption band of amide I at 1650 cm-1 was split into two bands, at 1650 cm-1 and 1633 cm-1, due to the presence of both α-helix and random coil protein conformations for melanoma and nevus. This was confirmed from the amide II band at 1550 cm-1, which shifted to lower frequencies at 1536 cm-1 and 1540 cm-1 for basal cell carcinoma and melanoma, respectively, indicating a damage of the native structure of proteins. The bands at 841 and 815 cm-1, which are assigned to B-DNA and Z-DNA, respectively, indicated that only the bands of the cancerous Z-DNA form are pronounced in melanoma, while in BCC both the characteristic bands of B-DNA and Z-DNA forms are found. CONCLUSION: It is proposed that the bands described above could be used as "diagnostic marker" bands for DNA forms, in the diagnosis of skin cancer.


Assuntos
Carcinoma Basocelular/diagnóstico , Melanoma/diagnóstico , Nevo/diagnóstico , Neoplasias Cutâneas/diagnóstico , Amidas/química , Amidas/isolamento & purificação , Biópsia , Carcinoma Basocelular/química , Carcinoma Basocelular/patologia , Detecção Precoce de Câncer , Humanos , Melanoma/química , Melanoma/patologia , Nevo/química , Nevo/patologia , Proteínas/química , Pele/química , Pele/patologia , Neoplasias Cutâneas/química , Neoplasias Cutâneas/patologia , Espectroscopia de Infravermelho com Transformada de Fourier
7.
In Vivo ; 30(5): 599-604, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27566078

RESUMO

In the present study we used non-distractive physicochemical methods to investigate the effect of γ-radiation on human articular cartilage. Comparison between the FT-IR (Fourier transform infrared) spectra before and after irradiation of the cartilage with different doses of radiation showed considerable changes in the spectra. It was found that for doses up to 2 Gy the collagen helices changed their structure from α-helix to random coil. By increasing the radiation dose it was found that the proteins' structure changed further to amyloid-like protein formation and to fragments of glycosaminoglycan chains, which were indicated in the IR spectra. Furthermore, comparison between the spectra of normal and irradiated cartilage, cancerous cartilage and cartilage from patients who received radiotherapy showed similarities in the spectra together with the formation of an aldehyde absorption band at 1740 cm(-1) suggesting that in all cases of cartilage examined,oxidative stress played major role in the damage progression of cartilage.


Assuntos
Cartilagem Articular/efeitos da radiação , Colágeno/química , Raios gama/efeitos adversos , Estresse Oxidativo/efeitos da radiação , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Colágeno/efeitos da radiação , Glicosaminoglicanos/metabolismo , Humanos , Conformação Proteica/efeitos da radiação , Espectroscopia de Infravermelho com Transformada de Fourier
8.
Artigo em Inglês | MEDLINE | ID: mdl-24798903

RESUMO

The growth and sophistication of geographic information systems (GIS) have propelled us into a new era of environmental analyses. Air pollution is a growing concern in populated areas as many recent studies have associated high levels of pollution with increased illnesses and mortality. The study will focus on the toxicity levels incurred by radioactive lignite-burning Power Generation facilities located in Megalopolis, Greece. An estimate of pollution emissions followed by dispersion simulations for various atmospheric conditions will be given. The exercise will be integrated with a Geographical Information System (GIS) for defining the emission sources and visualizing the dispersion of pollutants over the geographical terrain. Data samples were collected from vegetation in the surrounding areas and analyzed for radioactivity. High energy levels (up to 4-5 times higher than recommended standards, (UNCEAR, 1982) were found in several samples containing (226)Ra, (232)Th, (234)Th, (40)K and (238)U. The study concludes that air quality and vegetation of the neighbouring areas is adversely affected by industrial waste. Greater pollution controls and air quality monitoring should be applied for the benefit and health of its citizens. Radioactivity in food and water and inhaled air become very dangerous for public health thus, the levels of radioactivity should be kept within UNCEAR 1982 limits.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar/análise , Centrais Elétricas , Simulação por Computador , Fabaceae/química , Sistemas de Informação Geográfica , Grécia , Resíduos Industriais
9.
Artigo em Inglês | MEDLINE | ID: mdl-17474000

RESUMO

This study examined the atmospheric pollution created by industry and traffic areas nearby the city of Kavala and the mortality of citizens in the region. The mortality data spanned over a period of 30 years. The statistical data on mortality was collected from 1968 to 1998. The causes of mortality analyzed in this study were cancer, cardiovascular deaths and pulmonary deaths. The results of this study were compared with other Greek cities. Air measurements were made over a period of 6 months and included levels of gaseous emissions as well as concentrations of Volatile Organic Compounds (VOCs), near the city of Kavala, where reservoirs of petroleum and exploitation of crude oil were present. Samples of air were collected from ambient surroundings near the industrial area and fuel oil facilities. The results obtained from the study indicated the presence of aromatic and aliphatic hydrocarbons and other gaseous pollutants such as, methane, o-, m-, p-xylene and ethylbenzene, etc. In some cases the levels exceeded the concentration limits specified by the air quality standards. Offensive odors were also detected (H2S). The study revealed that adverse environmental impact of air pollutants is a major concern in the industrial centers more than in the rural areas. This poses a threat to the public health and may induce disease and premature deaths. These air pollutants play an important role in air quality.


Assuntos
Poluentes Atmosféricos/toxicidade , Causas de Morte , População Urbana , Grécia/epidemiologia , Humanos , Volatilização
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