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1.
Int J Cosmet Sci ; 44(1): 82-90, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34860415

RESUMO

OBJECTIVE: Human hair is regularly subjected to chemical and physical insults, such as heat, UV-irradiation and alkaline hair care products. These insults result in molecular modifications at the hair protein level that underpin mechanical and sensory property changes in the fibres. These changes can manifest itself in reduced hair quality and performance attributes observable to the consumer. In this work, changes in protein modification as a result of heat and alkaline treatments are determined. METHODS: Redox proteomic profiling using high-resolution mass spectrometry was applied to map and evaluate amino acid residue modifications in human hair exposed to a combination of thermal treatments and alkali exposure with the aim to understand the underlying chemical processes. RESULTS: Our results show that an increase in redox-related modifications is associated with exposure to higher levels of hydrothermal and alkaline insult. Post-translational modification profiling at the protein primary structural level delivered some further insights into the site-specificity of these modifications, with a clear increase in the number of cysteic acid modifications noticed in samples subjected to more extreme insults. CONCLUSION: Pinpointing modification sides within proteins and the hair shaft proteome can be used as a basis for employing mitigation or repair strategies of hair protein damage caused by environmental or hair treatment-related insults.


OBJECTIF: Les cheveux humains sont sujet à de nombreuses agressions physiques et chimiques telles que la chaleur, les radiations ultra-violettes et les produits alcalins d'entretien des cheveux. Ces agressions entrainent des modifications moléculaires dans les protéines constituant les cheveux et elles conduisent aussi à des changements mécaniques et sensoriels des fibres capillaires. Les manifestations possibles de ces transformations sont une baisse, visible pour le consommateur, de la qualité et des indicateurs de performance des cheveux. Lors de cette étude, nous mettons en évidence les changements au niveau protéique liés à la chaleur et aux traitements alcalins. MÉTHODES: Les méthodes de profilage d'oxydoréduction protéomique utilisant des spectromètres de masses à haute résolution ont été utilisées afin d'évaluer les modifications des amino-acides dans les cheveux humains après exposition à plusieurs combinaisons de traitements thermiques et alcalins dans le but de comprendre les processus chimiques impliqués. RÉSULTATS: Nos résultats montrent que l'augmentation des modifications d'oxydoréduction est associée à des niveaux élevés d'exposition aux traitements thermiques et/ou alcalins. Le profilage des modifications post-translationnelles des structures primaires des protéines ont permis de mieux comprendre les spécificités de ces modifications ; notamment une augmentation nette du nombre des modifications des acides cystéiques liée aux traitements les plus agressifs. CONCLUSION: Ce travail d'identification des modifications engendrées par les agressions liées aux traitements capillaires ou environnementales peut désormais servir de base pour évaluer et mettre en place des techniques de réduction des risques, protection et de réparation des protéines des cheveux.


Assuntos
Proteínas , Proteômica , Cabelo/química , Humanos , Espectrometria de Massas , Oxirredução , Proteínas/análise , Proteômica/métodos
2.
Int J Cosmet Sci ; 43 Suppl 1: S34-S41, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34426987

RESUMO

OBJECTIVE: Determining the amount of hair on the scalp has always been an important metric of patient satisfaction for hair growth and hair retention technologies. While simple in concept, this measurement is a difficult, resource intensive task for the dermatologist and the research scientist. Specifically, counting and measuring hair in phototrichogram images is very time consuming and labour intensive. Due to cost, often only a fraction of available images is manually analysed. There is a need for an automated method that can significantly increase speed and throughput while reducing the cost of counting and measuring hair in phototrichogram images. METHODS: Recent advances in machine learning and deep convolutional neural networks (deep learning) have led to a revolution in the analysis of image, video, speech, text and other sensor data. Image diagnostics have seen remarkable improvements with completely automated methods outperforming both human experts and human-engineered analysis methods. Deep learning methods can also provide speed and cost benefits. To enable use of a deep learning, we created a data set of 288 manually annotated phototrichogram images with marked location and length of each hair (the training dataset). We designed a custom neural network architecture and custom image processing algorithms to best utilize the available training data and to maximize performance for hair counting and length measurement. The performance of the algorithm was qualified by comparing hair count and length measurements to an independent ground truth method, the semi-manual Canfield's Hair Metrix method. RESULTS: Leveraging deep neural networks, we have developed capability to apply machine learning to reduce the time needed to acquire data from phototrichograms of patients' scalp from months to seconds. Our algorithm enables fast and fully automated hair counting and length measurement. The algorithm shows high agreement with human manually assisted analysis (ground truth). CONCLUSIONS: We have trained and deployed an algorithm utilizing this technology and have demonstrated the reproducibility, accuracy and speed of this algorithm that, once deployed, requires little to no recurring cost or manual intervention for its operation. The method allows fast analysis of large number of images, reducing study cost and significantly reducing study analysis time.


Assuntos
Cabelo/anatomia & histologia , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , Idoso , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade
3.
Int J Cosmet Sci ; 43 Suppl 1: S26-S33, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34424549

RESUMO

OBJECTIVE: Increasing scalp hair fullness is a global unmet consumer need. An approach to decrease hair shedding by reducing scalp stratum corneum oxidation via a combination of antioxidant and barrier-enhancing technologies has been previously demonstrated. The purpose of this study was to test the effectiveness of the individual antioxidant piroctone olamine in two different product forms (shampoo or leave-on product) for activity to improve hair retention. METHODS: Female subjects with self-perceived hair thinning participated in an 8-week, double-blind, placebo-controlled, randomized clinical study to evaluate either a piroctone olamine (PO) containing shampoo or a PO containing leave on treatment, each relative to their corresponding placebo formulation Too many periods. Results for phototrichograms, TEWL, and biomarker analysis of scalp condition for the shampoo treatments are discussed. Phototrichogram results are shared for the assessment of the leave on treatment. RESULTS: Statistically significant increases in hair amount were observed by phototrichogram after use of both PO-containing products versus placebo formulations. The PO shampoo treatment also significantly decreased oxidative stress on the hair and scalp, and improved scalp condition as assessed by TEWL and scalp biomarker values. CONCLUSION: These results illustrate the effectiveness of a cosmetic antioxidant to improve scalp condition thereby improving hair retention. The observed improvements in scalp condition are consistent with previous reports with other antioxidant technologies and suggest that the hair retention effect was achieved by preventing oxidative damage to the scalp.


Assuntos
Alopecia/tratamento farmacológico , Antioxidantes/uso terapêutico , Etanolaminas/uso terapêutico , Preparações para Cabelo/uso terapêutico , Piridonas/uso terapêutico , Couro Cabeludo/efeitos dos fármacos , Administração Tópica , Adulto , Idoso , Antioxidantes/administração & dosagem , Método Duplo-Cego , Combinação de Medicamentos , Etanolaminas/administração & dosagem , Feminino , Preparações para Cabelo/administração & dosagem , Humanos , Pessoa de Meia-Idade , Piridonas/administração & dosagem
4.
Int J Cosmet Sci ; 43 Suppl 1: S14-S25, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34424558

RESUMO

OBJECTIVE: Increasing hair fullness is a global unmet need for many men and women. An approach to the problem is to decrease hair fall or shedding by reducing scalp stratum corneum oxidation and barrier damage to increase hair retention. This study evaluated a combination of functional antioxidants and barrier-enhancing cosmetic ingredients to improve scalp condition thereby enabling stronger hair anchorage and longer retention. METHODS: Male and female subjects with normal scalp condition and self-perceived hair thinning participated in a 24-week, double-blind, placebo-controlled, randomized clinical study assessing either a regimen of treatment shampoo and leave-on treatment containing functional antioxidant and barrier-enhancing agents or an identical placebo chassis shampoo control. The functional ingredients were piroctone olamine, zinc pyrithione, zinc carbonate, niacinamide, panthenol and caffeine. At baseline and after 8, 16 and 24 weeks of product use, several measurements were taken: hair shedding, total hair count (by phototrichogram), hair samples, TEWL and evaluation of biomarkers of scalp and hair conditions. Subjects also completed self-assessment questionnaires. RESULTS: Statistically significant effects for functional ingredient-containing treatment regimen versus a placebo control shampoo formulation were observed for reduced hair shedding, increased total hair count, reduced TEWL and improvement in scalp biomarker values. Subjects also noticed these improvements assessed via self-assessment questionnaires. CONCLUSIONS: These results establish that the use of functional antioxidant and barrier-enhancing agents to further improve scalp condition can enable a reduction in hair shedding and thus an increase in perceived hair fullness. The underlying improvements in scalp condition suggest the hair benefits were achieved as a result of improved scalp skin barrier and scalp condition leading to a viable preventative approach for hair thinning.


Assuntos
Alopecia/tratamento farmacológico , Antioxidantes/uso terapêutico , Preparações para Cabelo/uso terapêutico , Couro Cabeludo/efeitos dos fármacos , Administração Tópica , Adulto , Idoso , Antioxidantes/administração & dosagem , Biomarcadores/sangue , Método Duplo-Cego , Preparações para Cabelo/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade
5.
J Family Med Prim Care ; 10(4): 1785-1788, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34123929

RESUMO

We report a case of a 51-year-old male with minimal past medical history who presented to his primary care provider with nausea, vomiting and constipation in the outpatient setting. Concomitantly, he was found to have a renal injury, anemia and lytic lesions which were confirmed to be due to multiple myeloma. After further investigation of the gastrointestinal symptoms, he was diagnosed with gastroparesis. This case represents an unusual presentation of gastroparesis, diagnosed at the same time as multiple myeloma, for which there has yet to be a published association. Here we detail the case, review gastric emptying physiology, the diagnostic criteria for gastroparesis and hypothesize the connection if it might have with multiple myeloma.

6.
Forensic Sci Int Genet ; 47: 102309, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32485593

RESUMO

Recent reports highlight possible improvements in individual identification using proteomic information from human hair evidence. These reports have stimulated investigation of parameters that affect the utility of proteomic information. In addition to variables already studied relating to processing technique and anatomic origin of hair shafts, an important variable is hair ageing. Present work focuses on the effect of age on protein profiling and analysis of genetically variant peptides (GVPs). Hair protein profiles may be affected by developmental and physiological changes with age of the donor, exposure to different environmental conditions and intrinsic processes, including during storage. First, to explore whether general trends were evident in the population at different ages, hair samples were analyzed from groups of different subjects in their 20's, 40's and 60's. No significant differences were seen as a function of age, but consistent differences were evident between European American and African American hair profiles. Second, samples collected from single individuals at different ages were analyzed. Mostly, these showed few protein expression level differences over periods of 10 years or less, but samples from subjects at 44 and 65 year intervals were distinctly different in profile. The results indicate that use of protein profiling for personal identification, if practical, would be limited to decadal time intervals. Moreover, batch effects were clearly evident in samples processed by different staff. To investigate the contribution of storage (at room temperature) in affecting the outcomes, the same proteomic digests were analyzed for GVPs. In samples stored over 10 years, GVPs were reduced in number in parallel with the yield of identified proteins and unique peptides. However, a very different picture emerged with respect to personal identification. Numbers of GVPs sufficed to distinguish individuals despite the age differences of the samples. As a practical matter, three hair samples per person provided nearly the maximal number obtained from 5 or 6 samples. The random match probability (where the log increased in proportion to the number of GVPs) reached as high as 1 in 108. The data indicate that GVP results are dependent on the single nucleotide polymorphism profile of the donor genome, where environmental/processing factors affect only the yield, and thus are consistent despite the ages of the donors and samples and batchwise effects in processing. This conclusion is critical for application to casework where the samples may be in storage for long periods and used to match samples recently collected.


Assuntos
Envelhecimento , Cabelo/metabolismo , Peptídeos/metabolismo , Polimorfismo de Nucleotídeo Único , Proteínas/metabolismo , Adulto , Negro ou Afro-Americano , Cromatografia Líquida , Feminino , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Peptídeos/genética , Proteínas/genética , Proteômica , População Branca , Adulto Jovem
7.
Ecol Evol ; 8(23): 12221-12237, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30598813

RESUMO

This study examines the fine-scale population genetic structure and phylogeography of the spiny lobster Panulirus homarus in the Western Indian Ocean. A seascape genetics approach was used to relate the observed genetic structure based on 21 microsatellite loci to ocean circulation patterns, and to determine the influence of latitude, sea surface temperature (SST), and ocean turbidity (KD490) on population-level processes. At a geospatial level, the genetic clusters recovered corresponded to three putative subspecies, P. h. rubellus from the SW Indian Ocean, P. h. megasculptus from the NW Indian Ocean, and P. h. homarus from the tropical region in-between. Virtual passive Lagrangian particles advected using satellite-derived ocean surface currents were used to simulate larval dispersal. In the SW Indian Ocean, the dispersion of particles tracked over a 4-month period provided insight into a steep genetic gradient observed at the Delagoa Bight, which separates P. h. rubellus and P. h. homarus. South of the contact zone, particles were advected southwestwards by prevailing boundary currents or were retained in nearshore eddies close to release locations. Some particles released in southeast Madagascar dispersed across the Mozambique Channel and reached the African shelf. Dispersal was characterized by high seasonal and inter-annual variability, and a large proportion of particles were dispersed far offshore and presumably lost. In the NW Indian Ocean, particles were retained within the Arabian Sea. Larval retention and self-recruitment in the Arabian Sea could explain the recent genetic divergence between P. h. megasculptus and P. h. homarus. Geographic distance and minimum SST were significantly associated with genetic differentiation in multivariate analysis, suggesting that larval tolerance to SST plays a role in shaping the population structure of P. homarus.

8.
PeerJ ; 2: e506, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25165623

RESUMO

Hair from different individuals can be distinguished by physical properties. Although some data exist on other species, examination of the individual molecular differences within the human hair shaft has not been thoroughly investigated. Shotgun proteomic analysis revealed considerable variation in profile among samples from Caucasian, African-American, Kenyan and Korean subjects. Within these ethnic groups, prominent keratin proteins served to distinguish individual profiles. Differences between ethnic groups, less marked, relied to a large extent on levels of keratin associated proteins. In samples from Caucasian subjects, hair shafts from axillary, beard, pubic and scalp regions exhibited distinguishable profiles, with the last being most different from the others. Finally, the profile of isolated hair cuticle cells was distinguished from that of total hair shaft by levels of more than 20 proteins, the majority of which were prominent keratins. The cuticle also exhibited relatively high levels of epidermal transglutaminase (TGM3), accounting for its observed low degree of protein extraction by denaturants. In addition to providing insight into hair structure, present findings may lead to improvements in differentiating hair from various ethnic origins and offer an approach to extending use of hair in crime scene evidence for distinguishing among individuals.

10.
Cardiovasc Res ; 69(4): 925-35, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16409996

RESUMO

OBJECTIVE: Studies have reported that administration of stromal cell-derived factor-1 (SDF-1), the ligand for the G-protein coupled receptor CXCR4, increased collateral blood flow in a mouse model of vascular insufficiency via recruitment of endothelial precursor cells (EPC). The present study investigated the contribution of mature endothelial cells in the actions of SDF-1. METHODS: The regulation of SDF-1 and CXCR4 was examined in the rat cornea cauterization (CC) and aortic ring (AR) model. The functional significance of the SDF-1/CXCR4 pathway was explored in cultured endothelial cells, the AR model, and on collateral blood flow in a rat model of vascular insufficiency. RESULTS: In the present study, the CXCR4 transcript was dramatically upregulated in the rat CC and AR explants, systems containing and lacking bone marrow-derived EPCs, respectively. Addition of AMD3100, a selective CXCR4 antagonist, had no effect on vessel growth in the AR alone, but completely inhibited SDF-1 mediated increases in vascular sprouting. In cultured endothelial cells, SDF-1 alone or in combination with vascular endothelial growth factor (VEGF) significantly enhanced cell survival and migration. Finally, systemic administration of SDF-1 in a rat model of arterial insufficiency enhanced collateral blood flow above vehicle control and equal to that of VEGF after 2 weeks of treatment. CONCLUSION: These studies support activation of the SDF-1/CXCR4 axis as a means to promote blood vessel growth and enhance collateral blood flow, at least in part, via direct effects on vascular endothelial cells.


Assuntos
Quimiocinas CXC/administração & dosagem , Endotélio Vascular/metabolismo , Doenças Vasculares Periféricas/tratamento farmacológico , Animais , Aorta , Biomarcadores/análise , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quimiocina CXCL12 , Quimiocinas CXC/genética , Quimiocinas CXC/uso terapêutico , Circulação Colateral , Córnea/irrigação sanguínea , Relação Dose-Resposta a Droga , Endotélio Vascular/patologia , Membro Posterior/irrigação sanguínea , Imuno-Histoquímica/métodos , Técnicas In Vitro , Modelos Animais , Neovascularização Patológica , Análise de Sequência com Séries de Oligonucleotídeos , Doenças Vasculares Periféricas/metabolismo , Doenças Vasculares Periféricas/patologia , RNA Mensageiro/análise , Ratos , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Fluxo Sanguíneo Regional/efeitos dos fármacos
11.
Exp Biol Med (Maywood) ; 230(3): 207-16, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15734724

RESUMO

The molecular basis of insulin resistance, a major risk factor for development of Type II diabetes, involves defective insulin signaling. Insulin-mediated signal transduction is negatively regulated by the phosphotyrosine phosphatase, PTP1B, and numerous studies have demonstrated that organo-vanadium compounds, which are nonselective phosphotyrosine phosphatase inhibitors, have insulin-mimetic properties. However, whether or not vanadium compounds can prevent the transition from insulin resistance to overt diabetes is unknown. We compared the ability of bis(maltolato)oxovanadium(IV) (BMOV), an orally bioavailable organo-vanadium compound, and rosiglitazone maleate (RSG), a known insulin sensitizer, to prevent development of diabetes in Zucker diabetic fatty (ZDF) rats. Treatment began at 6 weeks of age when animals are insulin resistant and hyperinsulinemic, but not yet hyperglycemic, and ended at 12 weeks of age, which is 4 weeks after ZDF rats typically develop overt diabetes. BMOV-treated ZDF rats did not develop hyperglycemia, showed significant improvement in insulin sensitivity, and retained normal pancreatic islet morphology and endocrine cell distribution, similar to RSG-treated animals. BMOV and RSG treatment also prevented the hyper-phagia and polydipsia present in untreated ZDF rats; however, BMOV-treated ZDF rats gained much less weight than did RSG-treated animals. Circulating levels of adiponectin decreased in untreated ZDF rats compared to lean controls, but these levels remained normal in BMOV-treated ZDF rats. In contrast, in RSG-treated ZDF rats, plasma adiponectin levels were nearly 4-fold higher than in lean control rats, primarily as a result of a large increase in the amount of low-molecular weight forms of adiponectin in circulation. These data demonstrate that phosphatase inhibition offers a new approach to diabetes prevention, one that may have advantages over current approaches.


Assuntos
Diabetes Mellitus Tipo 2/prevenção & controle , Inibidores Enzimáticos/farmacologia , Obesidade , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Pironas/farmacologia , Vanadatos/farmacologia , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/uso terapêutico , Teste de Tolerância a Glucose , Hiperinsulinismo , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Resistência à Insulina , Pâncreas/efeitos dos fármacos , Pâncreas/patologia , Proteínas Tirosina Fosfatases/metabolismo , Pironas/administração & dosagem , Pironas/uso terapêutico , Ratos , Ratos Zucker , Fatores de Tempo , Vanadatos/administração & dosagem , Vanadatos/uso terapêutico
12.
Am J Physiol Heart Circ Physiol ; 287(1): H268-76, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14988069

RESUMO

During embryonic development, the growth of blood vessels requires the coordinated activation of endothelial receptor tyrosine kinases (RTKs) such as vascular endothelial growth factor receptor-2 (VEGFR-2) and Tie-2. Similarly, in adulthood, activation of endothelial RTKs has been shown to enhance development of the collateral circulation and improve blood flow to ischemic tissues. Recent evidence suggests that RTK activation is negatively regulated by protein tyrosine phosphatases (PTPs). In this study, we used the nonselective PTP inhibitor bis(maltolato)oxovanadium IV (BMOV) to test the potential efficacy of PTP inhibition as a means to enhance endothelial RTK activation and improve collateral blood flow. In cultured endothelial cells, pretreatment with BMOV augmented VEGFR-2 and Tie-2 tyrosine phosphorylation and enhanced VEGF- and angiopoietin-1-mediated cell survival. In rat aortic ring explants, BMOV enhanced vessel sprouting, a process that can be influenced by both VEGFR-2 and Tie-2 activation. Moreover, 2 wk of BMOV treatment in a rat model of peripheral vascular disease enhanced collateral blood flow similarly to VEGF, and after 4 wk, BMOV was superior to VEGF. Taken together, these studies provide evidence that PTPs are important regulators of endothelial RTK activation and for the first time demonstrate the potential utility of phosphatase inhibition as a means to promote collateral development and enhance collateral blood flow to ischemic tissue.


Assuntos
Circulação Colateral , Proteínas Tirosina Fosfatases/metabolismo , Doenças Vasculares/fisiopatologia , Animais , Sobrevivência Celular , Células Cultivadas , Circulação Colateral/efeitos dos fármacos , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Humanos , Técnicas In Vitro , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Pironas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Proteína Tirosina Quinases/metabolismo , Receptor TIE-2/metabolismo , Vanadatos/farmacologia , Doenças Vasculares/patologia
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