Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 62
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
Wound Repair Regen ; 27(4): 298-308, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30761660

RESUMO

Keloid scars are described as benign fibro-proliferative dermal outgrowths that commonly occur in pigmented skin post cutaneous injury, and continue to grow beyond the boundary of the original wound margin. There is a lack of thorough understanding of keloid pathogenesis and thus keloid therapeutic options remain ill-defined. In view of the poor response to current therapy and high recurrence rates, there is an unmet need in improving our knowledge and therefore in identifying targeted and effective treatment strategies in management of keloids. Keloid research however, is hampered by a lack of relevant animal models as keloids do not spontaneously occur in animals and are unique to human skin. Therefore, developing novel animal models and nonanimal models for functional evaluation of keloid cells and tissue for better understanding their pathobiology and response to putative candidate therapies are essential. Here, we present the key concepts and relevant emerging research on two-dimensional and three-dimensional cell and tissue models for functional testing of keloid scars. We will describe in detail current models including in vitro mono- and co-cultures, multi-cellular spheroids (organoids) and organotyopic cultures, ex vivo whole skin keloid tissue organ culture models as well as in vivo human patient models. Finally, we discuss the role played by time as the fourth dimension in a novel model that involves sequential temporal biopsies of human patients with keloids (a so called 4D in vivo human model). The use of these unique models will no doubt prove pivotal in identification of new drug targets as well as biomarkers, in functional testing of emerging novel therapeutics, and in enhancing our understanding of keloid disease biology.


Assuntos
Simulação por Computador , Queloide/patologia , Técnicas de Cultura de Órgãos , Organoides/patologia , Pele/patologia , Animais , Fibroblastos/citologia , Humanos , Queloide/tratamento farmacológico , Modelos Biológicos , Terapia de Alvo Molecular , Técnicas de Cultura de Órgãos/métodos , Fenômenos Fisiológicos da Pele , Cicatrização
3.
Am J Hum Genet ; 93(6): 1100-7, 2013 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-24268661

RESUMO

Congenital poikiloderma is characterized by a combination of mottled pigmentation, telangiectasia, and epidermal atrophy in the first few months of life. We have previously described a South African European-descent family affected by a rare autosomal-dominant form of hereditary fibrosing poikiloderma accompanied by tendon contracture, myopathy, and pulmonary fibrosis. Here, we report the identification of causative mutations in FAM111B by whole-exome sequencing. In total, three FAM111B missense mutations were identified in five kindreds of different ethnic backgrounds. The mutation segregated with the disease in one large pedigree, and mutations were de novo in two other pedigrees. All three mutations were absent from public databases and were not observed on Sanger sequencing of 388 ethnically matched control subjects. The three single-nucleotide mutations code for amino acid changes that are clustered within a putative trypsin-like cysteine/serine peptidase domain of FAM111B. These findings provide evidence of the involvement of FAM111B in congenital poikiloderma and multisystem fibrosis.


Assuntos
Proteínas de Ciclo Celular/genética , Contratura/fisiopatologia , Doenças Musculares/complicações , Mutação , Fibrose Pulmonar/complicações , Síndrome de Rothmund-Thomson/complicações , Síndrome de Rothmund-Thomson/genética , Tendões/fisiopatologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Linhagem , Fenótipo , Síndrome de Rothmund-Thomson/diagnóstico , Adulto Jovem
4.
Pediatr Dermatol ; 33(1): 99-102, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26572929

RESUMO

There is a sense that many patients seen at referral centers could be managed at a primary health care level. The objective of the current study was to examine the range of diagnoses among consultations at the Red Cross Children's Hospital in Cape Town, South Africa, to help develop a strategy for targeted education of primary health care personnel. This was a retrospective review of data for children seen at a pediatric dermatology clinic from 2005 to 2010, recorded according to International Classification of Diseases coding and compared with published data from similar clinical settings. There were 13,253 clinic visits, with 4,789 patients seen (median age 4.8 yrs, range 2 days to 18.6 yrs). The top 10 diagnoses accounted for 88.5% of consultations (59.5% atopic eczema [AE], 7.1% seborrheic dermatitis [SD], 4.2% superficial mycoses, 3.1% molluscum contagiosum, 2.8% vitiligo, 2.7% viral warts, 2.4% prurigo or scabies, 2.3% psoriasis, 2.3% hemangioma, 2.1% impetigo). Disease prevalence was somewhat different during the first year of life (AE 43.7%, SD 18.6%, hemangiomas 13.4%). Inflammatory dermatoses (76.6%) were more prevalent than infections and infestations (14.5%). The disease spectrum was similar to that in developed countries, although AE prevalence was higher in this study (followed by London 36%, Greece 35%, and Hong Kong 33%) than in 19 published studies. The top 10 diagnoses accounted for more than 70% of diagnoses in 12 studies. The retrospective nature and setting at a specialist clinic increased bias and limited generalizability. Focused education on the optimal care of common diseases, especially AE, could reduce referrals, improve access, and allow specialists at tertiary centers more time to manage complex and uncommon dermatoses.


Assuntos
Assistência Ambulatorial/estatística & dados numéricos , Dermatologia/educação , Encaminhamento e Consulta/estatística & dados numéricos , Dermatopatias/diagnóstico , Adolescente , Criança , Pré-Escolar , Dermatologia/estatística & dados numéricos , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , África do Sul
6.
Pediatr Allergy Immunol ; 25(6): 572-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25201137

RESUMO

BACKGROUND: The prevalence of food allergy in South Africa is unknown, but previously thought to be rare in black South Africans. This study aimed to determine the prevalence of, and risk factors for, IgE-mediated food allergy in South African children with atopic dermatitis (AD). METHODOLOGY: This was a prospective, observational study in a paediatric university hospital in Cape Town. Children with AD, aged 6 months to 10 yrs, were randomly recruited from the dermatology clinic. They were assessed for sensitization and allergy by questionnaire, skin prick tests, Immuno Solid Phase Allergen Chip (ISAC) test and incremental food challenges. RESULTS: 100 participants (59 black Africans and 41 of mixed race) were enrolled, median age 42 months. There were high overall rates of food sensitization (66%) and food allergy (40%). Egg (25%) and peanut (24%) were the most common allergies. Black participants had comparable sensitization (69% vs. 61%) but lower allergy rates (34% vs. 46%) than mixed race participants. This was especially evident for peanut allergy (15% Blacks vs. 37% mixed race allergic to peanut, p = 0.01). Early-onset AD (<6 months), severe eczema, and young age <2 yrs were significant risk factors for food allergy. CONCLUSION: The prevalence of food allergy is unexpectedly high in South African children with AD, and comparable with food allergy rates in patients with AD in developed countries. There are ethnic differences, with significantly lower peanut allergy rates in Blacks compared to mixed race patients. These results are not generalizable to an unselected South African population, which requires further study.


Assuntos
População Negra , Dermatite Atópica/epidemiologia , Hipersensibilidade Alimentar/epidemiologia , Idade de Início , Alérgenos/imunologia , Arachis/imunologia , Criança , Pré-Escolar , Dermatite Atópica/complicações , Feminino , Hipersensibilidade Alimentar/complicações , Humanos , Imunoglobulina E/sangue , Lactente , Masculino , Prevalência , Estudos Prospectivos , Fatores de Risco , Testes Cutâneos , África do Sul
7.
J Am Acad Dermatol ; 70(2): 276-80, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24332313

RESUMO

BACKGROUND: Brazilian keratin treatment (BKT) and similar straightening products fix and retain a straight shape even when the hair is wet. Unacceptably high concentrations of formaldehyde have been reported in such products. OBJECTIVE: We sought to measure the formaldehyde concentration in all BKT brands marketed in South Africa in 2012. METHODS: We quantified formaldehyde by high-performance liquid chromatography with ultraviolet light detection after derivatization with dinitrophenylhydrazine. All components of 7 identified commercial brands were each tested 3 times. RESULTS: The maximum safe concentration of formaldehyde set by the US Cosmetic Ingredient Review Expert Panel is less than 0.2%. Of the 7 commercial BKT brands, 6 had formaldehyde levels that ranged from 0.96% to 1.4%, ie, 5 times higher than the recommended level; these included 5 brands labeled formaldehyde-free. LIMITATIONS: The study is limited by not including all internationally available BKT products. CONCLUSIONS: Formaldehyde concentrations in BKT products may exceed recommended levels and serve as a health hazard. Industry monitoring is needed to improve compliance and protection of hairdressers and consumers.


Assuntos
Barbearia , Monitoramento Ambiental , Formaldeído/análise , Preparações para Cabelo/química , Exposição Ocupacional/análise , Cromatografia Líquida de Alta Pressão/métodos , Qualidade de Produtos para o Consumidor , Estudos Transversais , Humanos , Queratinas Específicas do Cabelo , Espectroscopia de Ressonância Magnética , Marketing , Concentração Máxima Permitida , Medição de Risco , África do Sul
8.
Front Immunol ; 15: 1326728, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38915394

RESUMO

Keloids are a common connective tissue disorder with an ill-understood etiopathogenesis and no effective treatment. This is exacerbated because of the absence of an animal model. Patient-derived primary keloid cells are insufficient as they age through passaging and have a limited supply. Therefore, there is an unmet need for development of a cellular model that can consistently and faithfully represent keloid's pathognomic features. In view of this, we developed keloid-derived immortalized fibroblast (KDIF) cell lines from primary keloid fibroblasts (PKF) by transfecting the human telomerase reverse transcriptase (hTERT) gene. The TERT gene encodes the catalytic subunit of the telomerase enzyme, which is responsible for maintaining the cellular replicative potential (cellular immortalization). Primary fibroblasts from keloid-specific lesional (peripheral, middle, and top) as well as extralesional sites were isolated and evaluated for cell line development and comparative cellular characteristics by employing qRT-PCR and immunofluorescence staining. Moreover, the immortalized behavior of KDIF cell lines was evaluated by comparing with cutaneous fibrosarcoma and dermatofibrosarcoma protuberans cell lines. Stable KDIF cell lines with elevated expression of hTERT exhibited the cellular characteristics of site-specific keloid fibroblasts. Histochemical staining for ß-galactosidase revealed a significantly lower number of ß-gal-positive cells in all three KDIF cell lines compared with that in PKFs. The cell growth curve pattern was studied over 10 passages for all three KDIF cell lines and was compared with the control groups. The results showed that all three KDIF cell lines grew significantly faster and obtained a fast growing characteristic as compared to primary keloid and normal fibroblasts. Phenotypic behavior in growth potential is an indication of hTERT-mediated immortalized transformation. Cell migration analysis revealed that the top and middle KDIF cell lines exhibited similar migration trend as site-specific PKFs. Notably, peripheral KDIF cell line showed significantly enhanced cell migration in comparison to the primary peripheral fibroblasts. All KDIF cell lines expressed Collagen I protein as a keloid-associated fibrotic marker. Functional testing with triamcinolone inhibited cell migration in KDIF. ATCC short tandem repeat profiling validated the KDIF as keloid representative cell line. In summary, we provide the first novel KDIF cell lines. These cell lines overcome the limitations related to primary cell passaging and tissue supply due to immortalized features and present an accessible and consistent experimental model for keloid research.


Assuntos
Fibroblastos , Queloide , Telomerase , Humanos , Queloide/patologia , Queloide/metabolismo , Fibroblastos/metabolismo , Telomerase/genética , Telomerase/metabolismo , Linhagem Celular , Linhagem Celular Transformada , Masculino , Feminino , Adulto , Pessoa de Meia-Idade
9.
J Invest Dermatol ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39122141

RESUMO

Keloid disease (KD) is a common connective tissue disorder of unknown aetiopathogenesis with ill-defined treatment. Keloid scars present as exophytic fibroproliferative reticular lesions postcutaneous injury, and even though KD remains neoplastically benign, keloid lesions behave locally aggressive, invasive and expansive. To date, there is limited understanding and validation of biomarkers identified through combined proteomic and genomic evaluation of KD. Therefore, the aim in this study was to identify putative causative candidates in KD by performing a comprehensive proteomics analysis of subcellular fractions as well as the whole cell, coupled with transcriptomics data analysis of normal compared with KD fibroblasts. We then applied novel integrative bioinformatics analysis to demonstrate that NF-kB-p65 (RELA) from the cytosolic fraction and CAPN2 from the whole-cell lysate were statistically significantly upregulated in KD and associated with alterations in relevant key signaling pathways, including apoptosis. Our findings were further confirmed by showing upregulation of both RELA and CAPN2 in KD using flow cytometry and immunohistochemistry. Moreover, functional evaluation using real-time cell analysis and flow cytometry demonstrated that both omeprazole and dexamethasone inhibited the growth of KD fibroblasts by enhancing the rate of apoptosis. In conclusion, subcellular fractionation and metaproteogenomic analyses have identified, to our knowledge, 2 previously unreported biomarkers of significant relevance to keloid diagnostics and therapeutics.

11.
BMC Dermatol ; 13: 11, 2013 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-24152710

RESUMO

BACKGROUND: The Human T cell lymphotropic virus type 1 (HTLV-1)-associated infective dermatitis (IDH), is a chronic relapsing dermatitis which usually presents in children older than 2 years. A total of 300 cases have been reported worldwide (Latin America, the Caribbean and only 5 from Senegal). Neither IDH, nor its complications have been reported from the rest of Africa. We aimed to examine the clinical and aetiological characteristics of IDH in a cohort of South African children. METHODS: Attendees at the dermatology clinic at King Edward VIII Hospital, Durban underwent clinical examination. After obtaining consent those suspected of IDH had specimens taken for blood counts, immunoglobulins, serum protein electrophoresis, viral studies (including genotyping), skin swabs and stool examinations. RESULTS: Nineteen of 60 suspected cases recruited over 3 years met the diagnostic criteria for IDH. The male-to-female ratio was 1:2; mean age 8 years (range 0.7 to 15). Dermatitis mostly affected the scalp (78.9%) and axilla (73.7%); fewer children had nasal crusting (47.4%). Mean Ig A, IgG and IgM were raised, at 3.52 g/l, 22.6 g/l and 1.38 g/l, respectively. The median CD4 cell count was 1958 cells/mm3. Viral genotyping of all tested samples were positive for the Cosmopolitan, Subtype A (HTLV-1a). CONCLUSIONS: IDH is a distinct entity which also affects South Africans. Our patients were older at presentation and the majority did not present with nasal crusting as has been described in other countries.


Assuntos
Infecções por HTLV-I/complicações , Dermatopatias Virais/virologia , Adolescente , Idade de Início , Contagem de Linfócito CD4 , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Infecções por HTLV-I/virologia , Humanos , Imunoglobulinas/análise , Lactente , Masculino , Fatores de Risco , Dermatopatias Virais/imunologia , Dermatopatias Virais/patologia , África do Sul , Carga Viral
12.
JAAD Int ; 13: 150-158, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37823040

RESUMO

Androgenetic alopecia (AGA) is the most common nonscarring alopecia and is characterised by distinct gradual patterned hair loss. AGA is mediated by genetic predisposition and excessive follicular sensitivity to androgens, mainly in males, leading to the progressive conversion of scalp terminal hair into vellus hair. Although highly prevalent, it is not fatal but may have a severe psychosocial impact, especially on females and younger males. Significant advances have been made in understanding AGA's epidemiology and pathophysiology, but only 2 drugs remain approved by the FDA - finasteride and minoxidil. Prolonged use of these drugs, is a prerequisite for enhanced treatment response. However, this leads to poor medication adherence and adverse effects from extended use eg, the "postfinasteride syndrome" which persists beyond stopping the drug. Hence, there is a need for research on more effective alternative treatments for AGA, with fewer side effects. This paper reviewed recent advances in AGA pathophysiology and its treatment options. The recently characterized structure of type 2, 5-alpha reductase holds significance in comprehending present and prospective treatments of AGA.

13.
Cancer Treat Res Commun ; 34: 100679, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36610347

RESUMO

INTRODUCTION: Mutations in the uncharacterised human FAM111B gene are associated with POIKTMP, a rare multi-organ fibrosing disease. Recent studies also reported the overexpression of FAM111B in specific cancers. Moreover, FAM111B mutation screening may prove expensive in under-resourced facilities. Therefore, this study investigated its cellular function and dysfunction and described an inexpensive mutation screening method. MATERIALS AND METHODS: FAM111B expression was assessed in silico and validated in vitro in cell lines and primary skin fibroblasts from a South African POIKTMP-patient with the heterozygous FAM111B gene mutation: NM_198947.4: c.1861T>G (p. Tyr621Asp or Y621D) by qPCR and western blot. The cellular function of FAM111B was studied in HT1080 using various cell-based functional assays, and the Y621D mutation was genotyped by PCR-RFLP. RESULTS: Expression studies showed upregulated FAM111B mRNA and protein in the cancer cells. High FAM111B expression with robust nuclear localization occurred in HT1080. Additionally, expression data and cell-based assays indicated that FAM111B led to the upregulation of cell migration, decreased cell apoptosis, and modulatory effects on cell proliferation. Y621D mutation showed similar effects on cell migration but minimal impact on cell apoptosis. FAM111B mRNA and protein expression were markedly downregulated (p ≤ 0.05) in the POIKTMP-patient's fibroblasts. The PCR-RFLP method successfully genotyped Y621D gene mutation. DISCUSSION: FAM111B is a cancer-associated nuclear protein: Its modulation by mutations or overexpression may contribute to the malignancy of cancers and POIKTMP/fibrosis and poor clinical outcomes and represents a viable prognostic marker or therapeutic target. Furthermore, the PCR-RFLP method could prove a valuable tool for FAM111B mutation validation or screening in resource-constrained laboratories.


Assuntos
Proteínas de Ciclo Celular , Fibrossarcoma , Humanos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Mutação , Fibrossarcoma/genética , Genótipo , Polimorfismo de Fragmento de Restrição
15.
Dermatol Online J ; 18(9): 16, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23031383

RESUMO

The "fringe sign" introduced by Samrao and co-authors is a phenomenally descriptive catch phrase for translating study data for public education in the prevention of traction alopecia.


Assuntos
Alopecia/diagnóstico , Cabelo/patologia , Estresse Mecânico , Feminino , Humanos
16.
Adv Wound Care (New Rochelle) ; 11(4): 192-201, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34498914

RESUMO

Significance: Keloid scarring is cosmetically disfiguring, psychosocially distressing, and can be physically disabling. The pathophysiology of keloid formation is poorly understood and subsequently, treatment options are ill defined, limited, and largely unsatisfactory. Therefore, in view of its unsatisfactory and recalcitrant management, keloid therapy is often seen as a financial burden affecting both patients and the health care systems. Recent Advances: Increased research on the genetic and epigenetic mechanisms in keloids has broadened our understanding of keloid pathobiology. Epigenetic mechanisms, mainly DNA methylation, histone modification, and noncoding RNAs, are currently being widely investigated. Advances in genetic sequencing technology and reduced cost have aided this endeavor. Studies on blood and patient-derived keloid tissue are being done with therapeutic agents targeting epigenetic and genetic markers with the shared goal of identifying the pathways underlying the initiation and maintenance of keloids. These advances have informed us of multiple complex molecular pathways implicated in keloids, which are yet to be fully elucidated. Critical Issues: Improved understanding of the genetic and epigenetic causes implicated in keloids will enhance our knowledge of this enigmatic disorder and likely lead to the development of therapeutic targets based on the available clinical and experimental studies. Due to the incomplete knowledge of molecular targets involved in keloid scarring pathways, therapeutics is still lagging for this clinically and scientifically important condition. Future Directions: Focused research on the identification of molecular targets and mechanistic pathways implicated in keloids is required to generate novel antifibrotic therapeutic options to decrease or eradicate recurrence of the disease as well as associated morbidity and improve the quality of life of those affected with keloids.


Assuntos
Queloide , Metilação de DNA/genética , Epigênese Genética , Epigenômica , Humanos , Queloide/genética , Queloide/patologia , Queloide/terapia , Qualidade de Vida
17.
Biomater Res ; 26(1): 80, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36517896

RESUMO

Silicone breast implants are commonly used for cosmetic and oncologic surgical indications owing to their inertness and being nontoxic. However, complications including capsular contracture and anaplastic large cell lymphoma have been associated with certain breast implant surfaces over time. Novel implant surfaces and modifications of existing ones can directly impact cell-surface interactions and enhance biocompatibility and integration. The extent of foreign body response induced by breast implants influence implant success and integration into the body. This review highlights recent advances in breast implant surface technologies including modifications of implant surface topography and chemistry and effects on protein adsorption, and cell adhesion. A comprehensive online literature search was performed for relevant articles using the following keywords silicone breast implants, foreign body response, cell adhesion, protein adsorption, and cell-surface interaction. Properties of silicone breast implants impacting cell-material interactions including surface roughness, wettability, and stiffness, are discussed. Recent studies highlighting both silicone implant surface activation strategies and modifications to enhance biocompatibility in order to prevent capsular contracture formation and development of anaplastic large cell lymphoma are presented. Overall, breast implant surface modifications are being extensively investigated in order to improve implant biocompatibility to cater for increased demand for both cosmetic and oncologic surgeries.

18.
BJPsych Open ; 8(2): e54, 2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35197148

RESUMO

BACKGROUND: Suicidal behaviour remains a major public health concern and countries have responded by authoring guidelines to help mitigate death by suicide. Guidelines can include family-based recommendations, but evidence for the level and category of family-based involvement that is needed to effectively prevent suicide is unclear. AIMS: To explore the association between family-based recommendations in guidelines and countries' crude suicide rates. PROSPERO registration: CRD42019130195. METHOD: MEDLINE, Embase, PsycInfo, Web of Science and WHO MiNDbank databases and grey literature were searched within the past 20 years (1 January 2000 to 22 June 2020) for national guidelines giving family-based recommendations in any of three categories (prevention, intervention and postvention). RESULTS: We included 63 guidelines from 46 countries. All identified guidelines included at least one family-based recommendation. There were no statistically significant differences seen between mean World Health Organization crude suicide rates for countries that included only one, two or all three categories of family-based recommendations. However, a lower spread of crude suicide rates was seen when guideline recommendations included all three categories (mean crude suicide rates for one category: 11.09 (s.d. = 5.71); for two categories: 13.42 (s.d. = 7.76); for three categories: 10.68 (s.d. = 5.20); P = 0.478). CONCLUSIONS: Countries should work towards a comprehensive national suicide guideline that includes all categories of family-based recommendations. Countries with previously established guidelines should work towards the inclusion of evidence-based recommendations that have clear implementation plans to potentially help lower suicide rates.

19.
J Mech Behav Biomed Mater ; 118: 104394, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33691230

RESUMO

Cyclic testing of human hair reveals important details about the behaviour of fibres over many cycles of loading. Phenomena which are observed under static tensile tests give important clues about the form and behaviour of hair fibres, but these do not necessarily remain constant on the inevitable march to failure. In previous work, we demonstrated that curly fibres exhibited a toe-region during tensile tests. The form of curly fibres could be altered by mechanical manipulation but the curl could be recovered upon immersion in water. In this study, where straight and curly fibres are subject to cyclic loading, this characteristic toe-region was shown to be present in the first cycle of loading (for curly fibres). As the number of cycles increased (and the curly fibres progressively became straighter), the stress-strain response of curly fibres started to resemble that of straight fibres. This observation supports our previous hypothesis, which states that the toe-region can be attributed to the presence of a hydrogen bonding mechanism, which is present in curly fibres only, and can be altered by mechanical force. Interestingly, the alteration in load-bearing pattern in curly fibres did not necessarily translate to increased endurance, demonstrating that the relationship between fatigue and strength is a complex one in hair fibres.


Assuntos
Cabelo , Humanos , Teste de Materiais , Estresse Mecânico , Suporte de Carga
20.
Anticancer Agents Med Chem ; 21(2): 162-186, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32723261

RESUMO

BACKGROUND: Cutaneous malignancies most commonly arise from skin epidermal cells. These cancers may rapidly progress from benign to a metastatic phase. Surgical resection represents the gold standard therapeutic treatment of non-metastatic skin cancer while chemo- and/or radiotherapy are often used against metastatic tumors. However, these therapeutic treatments are limited by the development of resistance and toxic side effects, resulting from the passive accumulation of cytotoxic drugs within healthy cells. OBJECTIVE: This review aims to elucidate how the use of monoclonal Antibodies (mAbs) targeting specific Tumor Associated Antigens (TAAs) is paving the way to improved treatment. These mAbs are used as therapeutic or diagnostic carriers that can specifically deliver cytotoxic molecules, fluorophores or radiolabels to cancer cells that overexpress specific target antigens. RESULTS: mAbs raised against TAAs are widely in use for e.g. differential diagnosis, prognosis and therapy of skin cancers. Antibody-Drug Conjugates (ADCs) particularly show remarkable potential. The safest ADCs reported to date use non-toxic photo-activatable Photosensitizers (PSs), allowing targeted Photodynamic Therapy (PDT) resulting in targeted delivery of PS into cancer cells and selective killing after light activation without harming the normal cell population. The use of near-infrared-emitting PSs enables both diagnostic and therapeutic applications upon light activation at the specific wavelengths. CONCLUSION: Antibody-based approaches are presenting an array of opportunities to complement and improve current methods employed for skin cancer diagnosis and treatment.


Assuntos
Antígenos de Neoplasias/imunologia , Antineoplásicos Imunológicos/uso terapêutico , Imunoconjugados/uso terapêutico , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Animais , Antígenos de Neoplasias/análise , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Imunoconjugados/administração & dosagem , Imunoconjugados/farmacologia , Terapia de Alvo Molecular , Fotoquimioterapia , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/farmacologia , Prognóstico , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA