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1.
Heliyon ; 10(4): e25844, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38375262

RESUMO

In forensic medicine, estimating human skeletal remains' post-mortem interval (PMI) can be challenging. Following death, bones undergo a series of chemical and physical transformations due to their interactions with the surrounding environment. Post-mortem changes have been assessed using various methods, but estimating the PMI of skeletal remains could still be improved. We propose a new methodology with handheld hyperspectral imaging (HSI) system based on the first results from 104 human skeletal remains with PMIs ranging between 1 day and 2000 years. To differentiate between forensic and archaeological bone material, the Convolutional Neural Network analyzed 65.000 distinct diagnostic spectra: the classification accuracy was 0.58, 0.62, 0.73, 0.81, and 0.98 for PMIs of 0 week-2 weeks, 2 weeks-6 months, 6 months-1 year, 1 year-10 years, and >100 years, respectively. In conclusion, HSI can be used in forensic medicine to distinguish bone materials >100 years old from those <10 years old with an accuracy of 98%. The model has adequate predictive performance, and handheld HSI could serve as a novel approach to objectively and accurately determine the PMI of human skeletal remains.

2.
Bioengineering (Basel) ; 10(9)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37760120

RESUMO

Bone analyses using mid-infrared spectroscopy are gaining popularity, especially with handheld spectrometers that enable on-site testing as long as the data quality meets standards. In order to diagnose Staphylococcus epidermidis in human bone grafts, this study was carried out to compare the effectiveness of the Agilent 4300 Handheld Fourier-transform infrared with the Perkin Elmer Spectrum 100 attenuated-total-reflectance infrared spectroscopy benchtop instrument. The study analyzed 40 non-infected and 10 infected human bone samples with Staphylococcus epidermidis, collecting reflectance data between 650 cm-1 and 4000 cm-1, with a spectral resolution of 2 cm-1 (Agilent 4300 Handheld) and 0.5 cm-1 (Perkin Elmer Spectrum 100). The acquired spectral information was used for spectral and unsupervised classification, such as a principal component analysis. Both methods yielded significant results when using the recommended settings and data analysis strategies, detecting a loss in bone quality due to the infection. MIR spectroscopy provides a valuable diagnostic tool when there is a tissue shortage and time is of the essence. However, it is essential to conduct further research with larger sample sizes to verify its pros and cons thoroughly.

3.
Int J Mol Sci ; 25(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38203710

RESUMO

Osteomyelitis is a bone disease caused by bacteria that can damage bone. Raman handheld spectroscopy has emerged as a promising diagnostic tool for detecting bone infection and can be used intraoperatively during surgical procedures. This study involved 120 bone samples from 40 patients, with 80 samples infected with either Staphylococcus aureus or Staphylococcus epidermidis. Raman handheld spectroscopy demonstrated successful differentiation between healthy and infected bone samples and between the two types of bacterial pathogens. Raman handheld spectroscopy appears to be a promising diagnostic tool in bone infection and holds the potential to overcome many of the shortcomings of traditional diagnostic procedures. Further research, however, is required to confirm its diagnostic capabilities and consider other factors, such as the limit of pathogen detection and optimal calibration standards.


Assuntos
Doenças Ósseas , Osteomielite , Humanos , Osteomielite/diagnóstico , Calibragem , Nível de Saúde , Análise Espectral Raman
4.
Biology (Basel) ; 11(7)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-36101401

RESUMO

Estimating the post-mortem interval (PMI) of human skeletal remains is a critical issue of forensic analysis, with important limitations such as sample preparation and practicability. In this work, NIR spectroscopy (NIRONE® Sensor X; Spectral Engines, 61449, Germany) was applied to estimate the PMI of 104 human bone samples between 1 day and 2000 years. Reflectance data were repeatedly collected from eight independent spectrometers between 1950 and 1550 nm with a spectral resolution of 14 nm and a step size of 2 nm, each from the external and internal bone. An Artificial Neural Network was used to analyze the 66,560 distinct diagnostic spectra, and clearly distinguished between forensic and archaeological bone material: the classification accuracies for PMIs of 0−2 weeks, 2 weeks−6 months, 6 months−1 year, 1 year−10 years, and >100 years were 0.90, 0.94, 0.94, 0.93, and 1.00, respectively. PMI of archaeological bones could be determined with an accuracy of 100%, demonstrating the adequate predictive performance of the model. Applying a handheld NIR spectrometer to estimate the PMI of human skeletal remains is rapid and extends the repertoire of forensic analyses as a distinct, novel approach.

5.
Sci Rep ; 12(1): 6961, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484316

RESUMO

Comparative values are essential for the classification of orthopedic abnormalities and the assessment of a necessary therapy. At present, reference values for the upper body posture for healthy, male adults exist for the age groups of 18-35, 31-40 and 41-50 years. However, corresponding data on the decade of 51 to 60 year-old healthy men are still lacking. 23 parameters of the upper body posture were analyzed in 102 healthy male participants aged 51-60 (55.36 ± 2.78) years. The average height was 180.76 ± 7.81 cm with a weight of 88.22 ± 14.57 kg. The calculated BMI was 26.96 ± 3.92 kg/m2. In the habitual, upright position, the bare upper body was scanned three-dimensionally using video raster stereography. Mean or median values, confidence intervals, tolerance ranges and group comparisons, as well as correlations of BMI and physical activity, were calculated for all parameters. The spinal column parameters exhibited a good exploration of the frontal plane in the habitual standing position. In the sagittal plane, a slight, ventral inclination of the trunk with an increased kyphosis angle of the thoracic spine and increased thoracic bending angle was observed. The parameters of the pelvis showed a pronounced symmetry with deviations from the 0° axis within the measurement error margin of 1 mm/1°. The scapula height together with the scapula angles of the right and left side described a slightly elevated position of the left shoulder compared to the right side. The upper body posture is influenced by parameters of age, height, weight and BMI. Primarily there are significant correlations to measurements of trunk lengths D (age: p ≤ 0.02, rho = -0.23; height: p ≤ 0.001, rho = 0.58; weight: p ≤ 0.001, rho = 0.33), trunk lengths S (age: p ≤ 0.01, rho = -0.27; height: p ≤ 0.001, rho = 0.58; weight: p ≤ 0.001, rho = 0.32), pelvic distance (height: p ≤ 0.01, rho = 0.26; weight: p ≤ 0.001, rho = 0.32; BMI: p ≤ 0.03, rho = 0.22) and scapula distance (weight: p ≤ 0.001, rho = .32; BMI: p ≤ 0.01, rho = 0.27), but also to sagittal parameters of trunk decline (weight: p ≤ 0.001, rho = -0.29; BMI: p ≤ 0.01, rho = -0.24), thoracic bending angle (height: p ≤ 0.01, rho = 0.27) and kyphosis angle (BMI: p ≤ 0.03, rho = 0.21). The upper body posture of healthy men between the ages of 51 and 60 years was axially almost aligned and balanced. With the findings of this investigation and the reference values obtained, suitable comparative values for use in clinical practice and for further scientific studies with the same experimental set-up have been established.


Assuntos
Cifose , Postura , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Coluna Vertebral/diagnóstico por imagem , Tronco
6.
J Clin Med ; 10(14)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34300237

RESUMO

BACKGROUND: Scientific guidelines have been developed to update and harmonize exercise based cardiac rehabilitation (ebCR) in German speaking countries. Key recommendations for ebCR indications have recently been published in part 1 of this journal. The present part 2 updates the evidence with respect to contents and delivery of ebCR in clinical practice, focusing on exercise training (ET), psychological interventions (PI), patient education (PE). In addition, special patients' groups and new developments, such as telemedical (Tele) or home-based ebCR, are discussed as well. METHODS: Generation of evidence and search of literature have been described in part 1. RESULTS: Well documented evidence confirms the prognostic significance of ET in patients with coronary artery disease. Positive clinical effects of ET are described in patients with congestive heart failure, heart valve surgery or intervention, adults with congenital heart disease, and peripheral arterial disease. Specific recommendations for risk stratification and adequate exercise prescription for continuous-, interval-, and strength training are given in detail. PI when added to ebCR did not show significant positive effects in general. There was a positive trend towards reduction in depressive symptoms for "distress management" and "lifestyle changes". PE is able to increase patients' knowledge and motivation, as well as behavior changes, regarding physical activity, dietary habits, and smoking cessation. The evidence for distinct ebCR programs in special patients' groups is less clear. Studies on Tele-CR predominantly included low-risk patients. Hence, it is questionable, whether clinical results derived from studies in conventional ebCR may be transferred to Tele-CR. CONCLUSIONS: ET is the cornerstone of ebCR. Additional PI should be included, adjusted to the needs of the individual patient. PE is able to promote patients self-management, empowerment, and motivation. Diversity-sensitive structures should be established to interact with the needs of special patient groups and gender issues. Tele-CR should be further investigated as a valuable tool to implement ebCR more widely and effectively.

7.
J Med Chem ; 62(23): 10497-10525, 2019 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-31361135

RESUMO

Cysteine proteases are important targets for the discovery of novel therapeutics for many human diseases. From parasitic diseases to cancer, cysteine proteases follow a common mechanism, the formation of an encounter complex with subsequent nucleophilic reactivity of the catalytic cysteine thiol group toward the carbonyl carbon of a peptide bond or an electrophilic group of an inhibitor. Modulation of target enzymes occurs preferably by covalent modification, which imposes challenges in balancing cross-reactivity and selectivity. Given the resurgence of irreversible covalent inhibitors, can they impair off-target effects or are reversible covalent inhibitors a better route to selectivity? This Perspective addresses how small molecule inhibitors may achieve selectivity for different cathepsins, cruzain, rhodesain, and falcipain-2. We discuss target- and ligand-based designs emphasizing repurposing inhibitors from one cysteine protease to others.


Assuntos
Catepsinas/metabolismo , Cisteína Proteases/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Animais , Ligação Proteica
8.
J Sep Sci ; 41(3): 704-712, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29134782

RESUMO

We present a novel method for the quantitative determination of the clean-up efficiency to provide a calculated parameter for peak purity through iterative fitting in conjunction with design of experiments. Rosemary extracts were used and analyzed before and after solid-phase extraction using a self-fabricated mixed-mode sorbent based on poly(N-vinylimidazole/ethylene glycol dimethacrylate). Optimization was performed by variation of washing steps using a full three-level factorial design and response surface methodology. Separation efficiency of rosmarinic acid from interfering compounds was calculated using an iterative fit of Gaussian-like signals and quantifications were performed by the separate integration of the two interfering peak areas. Results and recoveries were analyzed using Design-Expert® software and revealed significant differences between the washing steps. Optimized parameters were considered and used for all further experiments. Furthermore, the solid-phase extraction procedure was tested and compared with commercial available sorbents. In contrast to generic protocols of the manufacturers, the optimized procedure showed excellent recoveries and clean-up rates for the polymer with ion exchange properties. Finally, rosemary extracts from different manufacturing areas and application types were studied to verify the developed method for its applicability. The cleaned-up extracts were analyzed by liquid chromatography with tandem mass spectrometry for detailed compound evaluation to exclude any interference from coeluting molecules.


Assuntos
Cromatografia Líquida de Alta Pressão , Cinamatos/análise , Depsídeos/análise , Extratos Vegetais/análise , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Imidazóis , Metacrilatos , Modelos Estatísticos , Distribuição Normal , Óleos Voláteis/análise , Polímeros , Reprodutibilidade dos Testes , Ácido Rosmarínico
9.
Toxicology ; 338: 17-29, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26449523

RESUMO

Since the α1-adrenergic antagonist prazosin (PRZ) was introduced into medicine as a treatment for hypertension and benign prostate hyperplasia, several studies have shown that PRZ induces apoptosis in various cell types and interferes with endocytotic trafficking. Because PRZ is also able to induce apoptosis in malignant cells, its cytotoxicity is a focus of interest in cancer research. Besides inducing apoptosis, PRZ was shown to serve as a substrate for an amine uptake mechanism originally discovered in neurones called transport-P. In line with our hypothesis that transport-P is an endocytotic mechanism also present in non-neuronal tissue and linked to the cytotoxicity of PRZ, we tested the uptake of QAPB, a fluorescent derivative of PRZ, in cancer cell lines in the presence of inhibitors of transport-P and endocytosis. Early endosomes and lysosomes were visualised by expression of RAB5-RFP and LAMP1-RFP, respectively; growth and viability of cells in the presence of PRZ and uptake inhibitors were also tested. Cancer cells showed co-localisation of QAPB with RAB5 and LAMP1 positive vesicles as well as tubulation of lysosomes. The uptake of QAPB was sensitive to transport-P inhibitors bafilomycin A1 (inhibits v-ATPase) and the antidepressant desipramine. Endocytosis inhibitors pitstop(®) 2 (general inhibitor of endocytosis), dynasore (dynamin inhibitor) and methyl-ß-cyclodextrin (cholesterol chelator) inhibited the uptake of QAPB. Bafilomycin A1 and methyl-ß-cyclodextrin but not desipramine were able to preserve growth and viability of cells in the presence of PRZ. In summary, we confirmed the hypothesis that the cellular uptake of QAPB/PRZ represents an endocytotic mechanism equivalent to transport-P. Endocytosis of QAPB/PRZ depends on a proton gradient, dynamin and cholesterol, and results in reorganisation of the LAMP1 positive endolysosomal system. Finally, the link seen between the cellular uptake of PRZ and cell death implies a still unknown pro-apoptotic membrane protein with affinity towards PRZ.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Prazosina/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 1/metabolismo , Antineoplásicos/metabolismo , Compostos de Boro/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colesterol/metabolismo , Dinaminas/metabolismo , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Corantes Fluorescentes/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Células K562 , Proteínas de Membrana Lisossomal/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Prazosina/análogos & derivados , Prazosina/metabolismo , Proteínas rab5 de Ligação ao GTP/metabolismo
10.
Science ; 334(6059): 1077-8, 2011 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-22116876
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