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1.
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.

2.
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
3.
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
4.
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.

5.
Exp Dermatol ; 31(5): 648-654, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35122327

RESUMO

Mutations in the human FAM111B gene are associated with a rare, hereditary multi-systemic fibrosing disease, POIKTMP. To date, there are ten POIKTMP-associated FAM111B gene mutations reported in thirty-six patients from five families globally. To investigate the clinical significance of these mutations, we summarized individual cases by clinical features and position of the reported FAM111B gene mutations as those within and outside the putative protease domain (MWPPD and MOPPD respectively). MWPPD cases had more clinical manifestations than MOPPD (25 versus 18). Although the most common clinical features of poikiloderma, alopecia and hypohidrosis overall occurred in 94%, 86% and 75% of all cases with no significant differences between the MOPPD and MWPPD group, less common features included life-threatening (pulmonary fibrosis 47% vs. 13%; liver abnormalities specifically cirrhosis 26% vs. 7%) and physically disabling conditions (myopathy 53% vs. 20%; tendon contracture 55% vs. 7%) were more common in MWPPD cases. Similarly, the only 2 cases of POIKTMP with fatal pancreatic cancers were both only in the MWPPD group. This review thus suggests that mutations within the putative protease domain of the FAM111B protein are associated with a broader range of clinical features and may predict increased POIKTMP severity and a poorer prognosis.


Assuntos
Dermatopatias Genéticas , Proteínas de Ciclo Celular/genética , Humanos , Mutação , Peptídeo Hidrolases/genética , Índice de Gravidade de Doença , Dermatopatias Genéticas/complicações
6.
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
7.
Pharmacol Res Perspect ; 8(4): e00598, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32643320

RESUMO

All classes of antiretroviral therapy (ART) have been implicated to induce adverse drug reactions such drug-induced liver injury (DILI) and immune-mediated adverse reactions in Human Immunodeficiency Virus (HIV) infected individuals. Patients that develop adverse drug reactions tend to have prolonged stays in hospital and may require to change to alternative regimens if reactions persist upon rechallenge or if rechallenge is contraindicated due to severity of the adverse reaction. Diagnosis of DILI remains a huge obstacle that delays timely interventions, since it is still based largely on exclusion of other causes. There is an urgent need to develop robust diagnostic and predictive biomarkers that could be used alongside the available tools (biopsy, imaging, and serological tests for liver enzymes) to give a specific diagnosis of DILI. Crucial to this is also achieving consensus in the definition of DILI so that robust studies can be undertaken. Importantly, it is crucial that we gain deeper insights into the mechanism of DILI so that patients can receive appropriate management. In general, it has been demonstrated that the mechanism of ART-induced liver injury is driven by four main mechanisms: mitochondrial toxicity, metabolic host-mediated injury, immune reconstitution, and hypersensitivity reactions. The focus of this review is to discuss the type and phenotypes of DILI that are caused by the first line ART regimens. Furthermore, we will summarize recent studies that have elucidated the cellular and molecular mechanisms of DILI both in vivo and in vitro.


Assuntos
Fármacos Anti-HIV/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Animais , Fármacos Anti-HIV/administração & dosagem , Biomarcadores/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Infecções por HIV/tratamento farmacológico , Humanos
8.
Dermatopathology (Basel) ; 6(2): 170-181, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31700859

RESUMO

Traction alopecia (TA) is hair loss caused by prolonged pulling or repetitive tension on scalp hair; it belongs to the biphasic group of primary alopecia. It is non-scarring, typically with preservation of follicular stem cells and the potential for regrowth of early lesions especially if traction hairstyles are stopped. However, the alopecia may become permanent (scarring) and fail to respond to treatment if the traction is excessive and prolonged. Hence, the ability to detect fibrosis early in these lesions could predict patients who respond to treatment. Histopathological diagnosis based on scalp biopsies has been used as a gold standard to delineate various forms of non-scarring alopecia and to differentiate them from scarring ones. However, due to potential discrepant reporting as a result of the type of biopsy, method of sectioning, and site of biopsy, histopathology often tends to be unreliable for the early recognition of fibrosis in TA. In this study, 45 patients were assessed using the marginal TA severity scoring system, and their biopsies (both longitudinal and transverse sections) were systematically assessed by three dermatopathologists, the aim being to correlate histopathological findings with clinical staging. Intraclass correlation coefficients were used to determine the level of agreement between the assessors. We found poor agreement of the identification and grading of perifollicular and interfollicular fibrosis (0.55 [0.23-0.75] and 0.01 [2.20-0.41], respectively), and no correlation could be drawn with the clinical severity score. Better methods of diagnosis are needed for grading and for recognition of early fibrosis in TA.

9.
Front Immunol ; 10: 1810, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31440236

RESUMO

Keloids are considered as benign fibroproliferative skin tumors growing beyond the site of the original dermal injury. Although traditionally viewed as a form of skin scarring, keloids display many cancer-like characteristics such as progressive uncontrolled growth, lack of spontaneous regression and extremely high rates of recurrence. Phenotypically, keloids are consistent with non-malignant dermal tumors that are due to the excessive overproduction of collagen which never metastasize. Within the remit of keloid pathobiology, there is increasing evidence for the various interplay of neoplastic-promoting and suppressing factors, which may explain its aggressive clinical behavior. Amongst the most compelling parallels between keloids and cancer are their shared cellular bioenergetics, epigenetic methylation profiles and epithelial-to-mesenchymal transition amongst other disease biological (genotypic and phenotypic) behaviors. This review explores the quasi-neoplastic or cancer-like properties of keloids and highlights areas for future study.


Assuntos
Queloide , Neoplasias , Animais , Doença Crônica , Humanos , Inflamação/imunologia , Inflamação/patologia , Queloide/imunologia , Queloide/patologia , Neoplasias/imunologia , Neoplasias/patologia
10.
Health Sci Rep ; 2(2): e103, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30809593

RESUMO

BACKGROUND: Cancer treatment in the 21st century has seen immense advances in optical imaging and immunotherapy. Significant progress has been made in the bioengineering and production of immunoconjugates to achieve the goal of specifically targeting tumors. DISCUSSION: In the 21st century, antibody drug conjugates (ADCs) have been the focus of immunotherapeutic strategies in cancer. ADCs combine the unique targeting of monoclonal antibodies (mAbs) with the cancer killing ability of cytotoxic drugs. However, due to random conjugation methods of drug to antibody, ADCs are associated with poor antigen specificity and low cytotoxicity, resulting in a drug to antibody ratio (DAR) >1. This means that the cytotoxic drugs in ADCs are conjugated randomly to antibodies, by cysteine or lysine residues. This generates heterogeneous ADC populations with 0 to 8 drugs per an antibody, each with distinct pharmacokinetic, efficacy, and toxicity properties. Additionally, heterogeneity is created not only by different antibody to ligand ratios but also by different sites of conjugation. Hence, much effort has been made to find and establish antibody conjugation strategies that enable us to better control stoichiometry and site-specificity. This includes utilizing protein self-labeling tags as fusion partners to the original protein. Site-specific conjugation is a significant characteristic of these engineered proteins. SNAP-tag is one such engineered self-labeling protein tag shown to have promising potential in cancer treatment. The SNAP-tag is fused to an antibody of choice and covalently reacts specifically in a 1:1 ratio with benzylguanine (BG) substrates, eg, fluorophores or photosensitizers, to target skin cancer. This makes SNAP-tag a versatile technique in optical imaging and photoimmunotherapy of skin cancer. CONCLUSION: SNAP-tag technology has the potential to contribute greatly to a broad range of molecular oncological applications because it combines efficacious tumor targeting, minimized local and systemic toxicity, and noninvasive assessment of diagnostic/prognostic molecular biomarkers of cancer.

11.
S Afr Med J ; 106(8): 782-6, 2016 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-27499402

RESUMO

BACKGROUND: Glutathione (GSH) is the most abundant naturally occurring non-protein thiol that protects mammalian cells from oxidative stress. Intravenous (IV) GSH for skin lightening is advertised by clinics in South Africa and internationally online, yet to date no published review on the subject exists. Methods. We conducted a MEDLINE search (to 30 September 2015) of GSH use for skin lightening and of all indications in medicine, to evaluate its safety. Results. Two controlled clinical trials (GSH capsules: 60 patients; 2% glutathione disulphide lotion: 30 patients) and a case series (GSH lozenges: 30 patients) reported a significantly decreased melanin index. A case series (GSH soap: 15 patients) reported skin lightening based on photography. Two systematic reviews of IV GSH for preventing chemo-induced toxicity and a third review of adjuvant therapy for Parkinson's disease altogether included 10 trials. Most trials reported either no or minimal GSH adverse effects, but all had treatment durations of a few doses (IV) or 4 -12 weeks. No study reported long-term IV GSH use. Conclusion. In spite of widespread reported use, there are no studies of IV GSH use for skin lightening or of its safety for chronic use (for any indication). The switch from brown to red melanin production may increase the risk of sun-induced skin cancers in previously protected individuals. Regulatory assessment of systemic GSH administration for cosmetic use by the Medicines Control Council seems urgently warranted to protect consumers from potential side-effects and from complications of IV infusions. This is especially concerning because of reports of GSH bought online. Effective topical GSH may be useful for hyperpigmented skin disorders, but this requires scientific scrutiny. The debate on the merits of cosmetic skin lightening is best handled by multidisciplinary teams.

12.
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
13.
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
14.
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
16.
J Am Acad Dermatol ; 62(3): 402-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20159306

RESUMO

BACKGROUND: 'Relaxers' are used by more than two thirds of African females to straighten hair, with easy grooming and increased length often cited as reasons. A recent study reported relaxed hair lengths much shorter than expected, suggesting increased fragility; the potential for scalp inflammation and scarring alopecia remains unclear. OBJECTIVE: To investigate the biochemical effects of 'relaxers' on hair. METHODS: With informed consent, included participants represented 3 groups: natural hair, asymptomatic relaxed hair, and symptomatic (brittle) relaxed hair. Biochemical analysis was performed by using a Biochrom 30 amino acid analyzer. Differences in amino acid levels were assessed using either Wilcoxon rank sum test or matched-pairs signed-rank test. RESULTS: There was a decrease in cystine, citrulline, and arginine; however, an increase in glutamine was found in all relaxed compared to natural hair. Cystine levels (milligram per gram amino acid nitrogen) were similar in natural proximal and distal hair: 14 mg/g (range, 4-15 mg/g) versus 14 mg/g (range, 12-15 mg/g); P = .139. In asymptomatic relaxed hair, cystine levels were higher in less frequently relaxed samples proximal to scalp: 7.5 mg/g (5.6-12) versus 3.3 mg/g (1.3-9.2); P = .005. Cystine levels in distal asymptomatic relaxed and symptomatic relaxed hair were similar to each other and to those in the genetic hair fragility disease trichothiodystrophy. LIMITATIONS: It was not possible to analyze lye and no-lye 'relaxers' separately. CONCLUSIONS: 'Relaxers' are associated with reduced cystine consistent with fragile damaged hair. A decrease in citrulline and glutamine has been associated with inflammation; prospective studies are needed to investigate whether or how 'relaxers' induce inflammation.


Assuntos
Aminoácidos/análise , Preparações para Cabelo/efeitos adversos , Cabelo/efeitos dos fármacos , Adolescente , Adulto , Arginina/análise , População Negra , Citrulina/análise , Cistina/análise , Feminino , Glutamina/análise , Cabelo/química , Preparações para Cabelo/farmacologia , Humanos , Síndromes de Tricotiodistrofia/induzido quimicamente
17.
AIDS Rev ; 11(4): 205-14, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19940947

RESUMO

Human T-cell lymphotropic virus type 1 prevalence estimates are usually based on serological screening of blood donors, pregnant women, and other selected population groups. Previously, data on the global epidemiology of human T-cell lymphotropic virus type 1 infection have been summarized unsystematically and without a focus on general populations. To assess the implications of the virus for healthcare systems it is essential to know its past and present prevalence. The widely cited estimate that 10-20 million people are infected with human T-cell lymphotropic virus type 1 worldwide was calculated from data that are now 25 years old. This estimate may therefore no longer reflect the global epidemiology. The objective of this study was to collate published data that are truly representative of the general population through a systematic review of the literature. Fifty-nine relevant studies were identified and the 17 that met the inclusion criteria were all cross-sectional designs; none reported incidence. The prevalence of human T-cell lymphotropic virus type 1 was highest in the two studies of Japanese islands (36.4%; 95% CI: 29.9-42.8) and lowest in studies from Mongolia, Malaysia and India. In Haiti the prevalence was 3.8% (95% CI: 1.78-5.86); in Africa between 6.6% (95% CI: 4.0-9.9) and 8.5% (95% CI: 6.99-10.10) in Gabon, and 1.05% (95% CI: 0.63-1.47) in Guinea. Only three studies were from West Africa and none were from the South; the only study from India was from the north of the country. We conclude that there is a paucity of general population data from countries in which human T-cell lymphotropic virus type 1 is endemic, and that new studies are required to reevaluate the global burden of infection.


Assuntos
Infecções por HTLV-I/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , África/epidemiologia , Ásia/epidemiologia , Haiti/epidemiologia , Humanos , Prevalência
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