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1.
Am J Hum Genet ; 107(1): 34-45, 2020 07 02.
Article in English | MEDLINE | ID: mdl-32497488

ABSTRACT

IFAP syndrome is a rare genetic disorder characterized by ichthyosis follicularis, atrichia, and photophobia. Previous research found that mutations in MBTPS2, encoding site-2-protease (S2P), underlie X-linked IFAP syndrome. The present report describes the identification via whole-exome sequencing of three heterozygous mutations in SREBF1 in 11 unrelated, ethnically diverse individuals with autosomal-dominant IFAP syndrome. SREBF1 encodes sterol regulatory element-binding protein 1 (SREBP1), which promotes the transcription of lipogenes involved in the biosynthesis of fatty acids and cholesterols. This process requires cleavage of SREBP1 by site-1-protease (S1P) and S2P and subsequent translocation into the nucleus where it binds to sterol regulatory elements (SRE). The three detected SREBF1 mutations caused substitution or deletion of residues 527, 528, and 530, which are crucial for S1P cleavage. In vitro investigation of SREBP1 variants demonstrated impaired S1P cleavage, which prohibited nuclear translocation of the transcriptionally active form of SREBP1. As a result, SREBP1 variants exhibited significantly lower transcriptional activity compared to the wild-type, as demonstrated via luciferase reporter assay. RNA sequencing of the scalp skin from IFAP-affected individuals revealed a dramatic reduction in transcript levels of low-density lipoprotein receptor (LDLR) and of keratin genes known to be expressed in the outer root sheath of hair follicles. An increased rate of in situ keratinocyte apoptosis, which might contribute to skin hyperkeratosis and hypotrichosis, was also detected in scalp samples from affected individuals. Together with previous research, the present findings suggest that SREBP signaling plays an essential role in epidermal differentiation, skin barrier formation, hair growth, and eye function.


Subject(s)
Arthrogryposis/genetics , Mutation/genetics , Sterol Regulatory Element Binding Protein 1/genetics , Adolescent , Adult , Child , Child, Preschool , Female , Gene Expression Regulation/genetics , Humans , Keratosis/genetics , Male , Middle Aged , Pedigree , Phenotype , Young Adult
2.
N Engl J Med ; 380(9): 833-841, 2019 02 28.
Article in English | MEDLINE | ID: mdl-30763140

ABSTRACT

BACKGROUND: Central centrifugal cicatricial alopecia (CCCA) is the most common form of scarring alopecia among women of African ancestry. The disease is occasionally observed to affect women in families in a manner that suggests an autosomal dominant trait and usually manifests clinically after intense hair grooming. We sought to determine whether there exists a genetic basis of CCCA and, if so, what it is. METHODS: We used exome sequencing in a group of women with alopecia (discovery set), compared the results with those in a public repository, and applied other filtering criteria to identify candidate genes. We then performed direct sequencing to identify disease-associated DNA variations and RNA sequencing, protein modeling, immunofluorescence staining, immunoblotting, and an enzymatic assay to evaluate the consequences of potential etiologic mutations. We used a replication set that consisted of women with CCCA to confirm the data obtained with the discovery set. RESULTS: In the discovery set, which included 16 patients, we identified one splice site and three heterozygous missense mutations in PADI3 in 5 patients (31%). (The approximate prevalence of the disease is up to 5.6%.) PADI3 encodes peptidyl arginine deiminase, type III (PADI3), an enzyme that post-translationally modifies other proteins that are essential to hair-shaft formation. All three CCCA-associated missense mutations in PADI3 affect highly conserved residues and are predicted to be pathogenic; protein modeling suggests that they result in protein misfolding. These mutations were found to result in reduced PADI3 expression, abnormal intracellular localization of the protein, and decreased enzymatic activity - findings that support their pathogenicity. Immunofluorescence staining showed decreased expression of PADI3 in biopsy samples of scalp skin obtained from patients with CCCA. We then directly sequenced PADI3 in an additional 42 patients (replication set) and observed genetic variants in 9 of them. A post hoc analysis of the combined data sets showed that the prevalence of PADI3 mutation was higher among patients with CCCA than in a control cohort of women of African ancestry (P = 0.002 by the chi-square test; P = 0.006 by Fisher's exact test; and after adjustment for relatedness of persons, P = 0.03 and P = 0.04, respectively). CONCLUSIONS: Mutations in PADI3, which encodes a protein that is essential to proper hair-shaft formation, were associated with CCCA. (Funded by the Ram Family Foundation and others.).


Subject(s)
Alopecia/genetics , Black or African American/genetics , Genetic Predisposition to Disease , Hair/growth & development , Mutation , Protein-Arginine Deiminases/genetics , Adolescent , Adult , Age of Onset , Alopecia/ethnology , Chi-Square Distribution , Cicatrix/genetics , Exome , Female , Heterozygote , Humans , Middle Aged , Mutagenesis , Pedigree , Protein-Arginine Deiminase Type 3 , Protein-Arginine Deiminases/metabolism , Scalp/pathology , Sequence Analysis, DNA
3.
Am J Hum Genet ; 103(5): 777-785, 2018 11 01.
Article in English | MEDLINE | ID: mdl-30401459

ABSTRACT

Hypotrichosis simplex (HS) is a rare form of hereditary alopecia characterized by childhood onset of diffuse and progressive scalp and body hair loss. Although research has identified a number of causal genes, genetic etiology in about 50% of HS cases remains unknown. The present report describes the identification via whole-exome sequencing of five different mutations in the gene LSS in three unrelated families with unexplained, potentially autosomal-recessive HS. Affected individuals showed sparse to absent lanugo-like scalp hair, sparse and brittle eyebrows, and sparse eyelashes and body hair. LSS encodes lanosterol synthase (LSS), which is a key enzyme in the cholesterol biosynthetic pathway. This pathway plays an important role in hair follicle biology. After localizing LSS protein expression in the hair shaft and bulb of the hair follicle, the impact of the mutations on keratinocytes was analyzed using immunoblotting and immunofluorescence. Interestingly, wild-type LSS was localized in the endoplasmic reticulum (ER), whereas mutant LSS proteins were localized in part outside of the ER. A plausible hypothesis is that this mislocalization has potential deleterious implications for hair follicle cells. Immunoblotting revealed no differences in the overall level of wild-type and mutant protein. Analyses of blood cholesterol levels revealed no decrease in cholesterol or cholesterol intermediates, thus supporting the previously proposed hypothesis of an alternative cholesterol pathway. The identification of LSS as causal gene for autosomal-recessive HS highlights the importance of the cholesterol pathway in hair follicle biology and may facilitate novel therapeutic approaches for hair loss disorders in general.


Subject(s)
Genes, Recessive/genetics , Intramolecular Transferases/genetics , Mutation/genetics , Adolescent , Adult , Alleles , Alopecia/genetics , Cholesterol/genetics , Endoplasmic Reticulum/genetics , Female , Hair/abnormalities , Hair Diseases/genetics , Humans , Hypotrichosis/genetics , Keratinocytes/pathology , Male , Pedigree , Young Adult
4.
Am J Hum Genet ; 99(6): 1292-1304, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-27866708

ABSTRACT

Uncombable hair syndrome (UHS), also known as "spun glass hair syndrome," "pili trianguli et canaliculi," or "cheveux incoiffables" is a rare anomaly of the hair shaft that occurs in children and improves with age. UHS is characterized by dry, frizzy, spangly, and often fair hair that is resistant to being combed flat. Until now, both simplex and familial UHS-affected case subjects with autosomal-dominant as well as -recessive inheritance have been reported. However, none of these case subjects were linked to a molecular genetic cause. Here, we report the identification of UHS-causative mutations located in the three genes PADI3 (peptidylarginine deiminase 3), TGM3 (transglutaminase 3), and TCHH (trichohyalin) in a total of 11 children. All of these individuals carry homozygous or compound heterozygous mutations in one of these three genes, indicating an autosomal-recessive inheritance pattern in the majority of UHS case subjects. The two enzymes PADI3 and TGM3, responsible for posttranslational protein modifications, and their target structural protein TCHH are all involved in hair shaft formation. Elucidation of the molecular outcomes of the disease-causing mutations by cell culture experiments and tridimensional protein models demonstrated clear differences in the structural organization and activity of mutant and wild-type proteins. Scanning electron microscopy observations revealed morphological alterations in hair coat of Padi3 knockout mice. All together, these findings elucidate the molecular genetic causes of UHS and shed light on its pathophysiology and hair physiology in general.


Subject(s)
Antigens/genetics , Hair Diseases/genetics , Hair/growth & development , Hydrolases/genetics , Intermediate Filament Proteins/genetics , Mutation , Transglutaminases/genetics , Adolescent , Animals , Base Sequence , Cell Line , Codon, Nonsense , Female , Hair/abnormalities , Hair/anatomy & histology , Hair/metabolism , Humans , Hydrolases/deficiency , Hydrolases/metabolism , Male , Mice , Mice, Knockout , Models, Molecular , Mutation, Missense/genetics , Protein Conformation , Protein-Arginine Deiminase Type 3 , Protein-Arginine Deiminases , Transglutaminases/deficiency , Transglutaminases/metabolism , Vibrissae/abnormalities
5.
Transfus Apher Sci ; 50(3): 340-8, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24780391

ABSTRACT

Extracorporeal photopheresis (ECP) is broadly used in adults with cutaneous T-cell lymphoma, acute or chronic graft-versus-host disease (GVHD), rejection of solid organ transplants, and a variety of autoimmune, cell-mediated diseases. The predominant use of ECP in children and adolescents is for treating GVHD. Children pose specific challenges to ECP, due to their unique physiology and to patient's size. Herein, we will focus on current clinical trials with ECP in children with GVHD, with an emphasis on technical and clinical issues that are peculiar to the paediatric setting.


Subject(s)
Graft Rejection/therapy , Graft vs Host Disease/therapy , Organ Transplantation , Photopheresis/methods , Acute Disease , Adolescent , Adult , Child , Child, Preschool , Chronic Disease , Female , Graft Rejection/immunology , Graft Rejection/pathology , Graft vs Host Disease/immunology , Graft vs Host Disease/pathology , Humans , Lymphoma, T-Cell, Cutaneous/immunology , Lymphoma, T-Cell, Cutaneous/pathology , Lymphoma, T-Cell, Cutaneous/therapy , Male
6.
Microorganisms ; 12(5)2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38792745

ABSTRACT

Cryptosporidium spp. and Microsporidia are opportunistic microorganisms with remarkable zoonotic transmission potential due to their capacity to infect humans and animals. The aim of this study was to evaluate the prevalence of these microorganisms in stool samples of animal and human origin. In total, 369 stool samples (205 from human patients with diarrhea and 164 of animal origin) were included in the study. Cryptosporidium spp. and Microsporidia presence were determined by using multiplex nested PCR. Positive results were analyzed by using Sanger sequencing of the amplicon, utilizing BLASTN and ClustalX software to confirm identification. Cryptosporidium spp. were found in 0.97% and 4.26% of human and animal samples, respectively. Enterocytozoon bieneusi was detected in human and animal stools in 6.82% and 3.05% of the samples, respectively. No associations were found when analyzing the presence of Cryptosporidium spp. and E. bieneusi and the demographic and clinical variables of patients and animals. This study demonstrates the presence of these microorganisms in human and animal samples from different species, and the most interesting findings are the detection of Cryptosporidium spp. in pets (e.g., rodents) that are not usually included in this type of study, and the identification of E. bieneusi in patients with diarrhea without underlying disease.

7.
Inflamm Bowel Dis ; 10(3): 234-9, 2004 May.
Article in English | MEDLINE | ID: mdl-15290917

ABSTRACT

BACKGROUND: To determine diagnostic accuracy of anti-Saccharomyces cerevisiae antibodies (ASCA) in identifying children with inflammatory bowel disease (IBD) and to differentiate Crohn's disease (CD) from other IBD forms; and to determine the effect of medical or surgical treatment and of disease location and activity on ASCA titers. METHODS: Serum samples were obtained from 196 IBD children and 142 controls. ASCA IgA and IgG titers were measured by ELISA. Measurements were repeated during the follow up of CD children. RESULTS: ASCA titers were significantly higher in CD than in other IBD and in control patients. Combination of IgA and IgG ASCA positivity was highly specific for CD. Medical treatment and disease location did not influence assay results. Significantly lower ASCA titers were obtained in CD children with intestinal resection compared to CD-affected children who did not undergo surgical resection. ASCA titers correlated significantly with disease activity, and children with severe active disease showed higher ASCA values compared to those in remission. A significant reduction of ASCA was observed during the follow-up of CD children when clinical remission was achieved. CONCLUSIONS: The diagnostic accuracy of ASCA is influenced by disease activity and this suggests an additional use for the follow-up of CD children of this assay.


Subject(s)
Antibodies, Fungal/blood , Inflammatory Bowel Diseases/diagnosis , Inflammatory Bowel Diseases/immunology , Saccharomyces cerevisiae/immunology , Adolescent , Adult , Case-Control Studies , Child , Child, Preschool , Crohn Disease/diagnosis , Crohn Disease/immunology , Diagnosis, Differential , Female , Humans , Infant , Male , Sensitivity and Specificity
9.
Ital J Pediatr ; 36: 50, 2010 Jul 20.
Article in English | MEDLINE | ID: mdl-20646270

ABSTRACT

A 12 year old boy presented with an acute onset of anisocoria and blurred vision. Ocular motility was normal but his right pupil was dilated, round but sluggishly reactive to light. There was no history of trauma, eye drops' instillation, nebulised drugs or local ointments. His past medical history was negative.A third nerve palsy was considered but the performed cerebral MRI was normal.On further anamnestic investigation the boy revealed that he had spent the morning doing gardening, and especially working on a "trumpet plant". Datura and Brugmansia are well known toxic plant; all Datura and Brugmasia plants contain, primarily in their seeds and flowers, tropane alkaloids such as scopolamine, hyoscyamine and atropine. Systemic and local intoxications have already been described.The day after anisocoria was much less evident and completely resolved in three days.We present this case of an unusual cause of mydriasis to underline once more the importance of a well and deeply conducted medical history.


Subject(s)
Anisocoria/chemically induced , Datura stramonium/poisoning , Plant Poisoning/etiology , Plants, Toxic/poisoning , Anisocoria/diagnosis , Child , Diagnosis, Differential , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Male , Plant Poisoning/diagnosis , Remission, Spontaneous
10.
J Pediatr Gastroenterol Nutr ; 42(1): 9-15, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16385247

ABSTRACT

OBJECTIVE: To assess the effectiveness of the combined use of fecal calprotectin (FC), anti-Saccharomyces cerevisiae antibody (ASCA), perinuclear staining antineutrophil antibody (pANCA), small intestinal permeability test (IP), and bowel wall ultrasonography measurement (BWUS) in the diagnostic work-up of children with suspected inflammatory bowel disease (IBD). METHODS: All children referred for initial assessment of possible IBD were eligible. Patients with symptoms or signs (right-lower quadrant mass, perianal disease, or hematochezia) mandating a complete work-up for IBD were excluded. All enrolled patients underwent a clinical, laboratory, radiographic, and endoscopic evaluation including biopsy examinations. The immunoglobulin (Ig)G and IgA ASCA, IgG pANCA, FC, IP, and BWUS were tested in all patients at the initial assessment. RESULTS: A final diagnosis of IBD was made in 27 patients: 17 Crohn disease and 10 ulcerative colitis. Eighteen children had other gastrointestinal diagnoses (8 functional bowel disorders, 5 food allergy-mediated diseases, 4 infectious enterocolitis, 1 familial Mediterranean fever). In patients with simultaneous abnormal values of FC, BWUS, and ASCA/pANCA, the estimated probability of having IBD was 99.47%. Patients with negative results on all tests had a 0.69% of probability of IBD. CONCLUSIONS: The incorporation of noninvasive diagnostic tests into the initial diagnostic approach may avoid unnecessary invasive procedures and facilitate clinical decision-making when the diagnosis of IBD in children is initially uncertain.


Subject(s)
Antibodies, Antineutrophil Cytoplasmic/analysis , Antibodies, Fungal/analysis , Diagnostic Tests, Routine/standards , Inflammatory Bowel Diseases/diagnosis , Leukocyte L1 Antigen Complex/analysis , Adolescent , Child , Colitis, Ulcerative/diagnosis , Colitis, Ulcerative/immunology , Colitis, Ulcerative/pathology , Crohn Disease/diagnosis , Crohn Disease/immunology , Crohn Disease/pathology , Diagnosis, Differential , Diagnostic Tests, Routine/methods , Feces/chemistry , Female , Humans , Inflammatory Bowel Diseases/immunology , Inflammatory Bowel Diseases/pathology , Intestine, Small/diagnostic imaging , Intestine, Small/pathology , Intestine, Small/physiology , Male , Permeability , Reproducibility of Results , Saccharomyces cerevisiae/immunology , Sensitivity and Specificity , Ultrasonography
11.
Ortodontia ; 44(6): 526-529, nov.-dez. 2011. tab
Article in Portuguese | LILACS, BBO | ID: lil-713850

ABSTRACT

Proposição: avaliar a citotoxicidade de bráquetes metálicos e cerâmicos em diferentesperiodos de tempo. Metodologia: foram avaliados bráquetes metálicos e cerâmicos deuma mesma marca comercial (3M Unitek, Monrovia, Califórnia) distribuídos em dois grupos:1) metálico (Victory Series); 2) cerâmico (TranscendTM). Três grupos controle foram avaliados:controle positivo (C+) constituído de um cilindro de amálgama, controle negativo (C-), bastãode vidro e controle de célula (CC), onde as células não foram expostas a nenhum material. Previamente,os bráquetes foram esterilizados em luz ultravioleta (UV). Após isso, foram imersosem meio mínimo essencial de Eagle (MEM) por 24 horas, onde então se procedeu a remoçãodo sobrenadante e a colocação em contato com fibroblastos L929. Avaliou-se a citotoxicidadeem quatro períodos (24, 48, 72 e 168 horas). Após contato com o meio, as células foramincubadas por mais 24 horas, onde então foram adicionados 100 ml do corante vermelho neutroa 0,01 %. Após isso foi realizada contagem de células viáveis em espectrofotômetro em umcomprimento de onda de 492 nm. Resultados: não foram encontradas diferenças estatísticasentre os grupos experimentais (1 e 2) com os grupos controle negativos e controle de célula(p ¼ 0,05). Conclusão: tanto os bráquetes cerâmicos quanto os metálicos não foram citotóxicosnos períodos de tempo avaliados.


Proposition: the purpose of this study is to evaluate the cytotoxicity of metal andceramic brackets in different periods of time. Methods: we evaluated metal and ceramic bracketsof the same trademark (3M Unitek, Monrovia, CAl divided into two groups: 1) metallic (victorySeries); 2) ceramic (TranscendTM) conventional. Three control groups have been evaluated:positive control (C +) consisting of amalgam cylinders, nega tive control group (C-) consistingof glass rods and Cell Control Group (CC) consisting of cells not exposed to any material. Alibrackets were previously sterilized under ultra-violet light (UV) and, then, immersed in Eagle'sminimum essential media (MEM) for 24 hours, after which the supernatants were removedand placed into contact with L929 fibroblast cells. Cytotoxicity was evaluated at 24, 48, 72and 168 hours. After contact with MEM, the cells were further incubated for 24 hours and100 ml of 0.01 % neutral red dye were added. After this period, the cells were fixed and viable cellcounting was performed by spectrophotometry at 492 nm wavelength. Results: Any statisticallysignificant difference was found between the experimental groups (1 and 2) and the nega tivecontrol and cell control groups (p > 0.05). Conclusions: both the metal and ceramic bracketsare not cytotoxic in the time periods evaluated.


Subject(s)
Fibroblasts , Materials Testing , Dental Materials/analysis , Dental Materials/toxicity , Orthodontic Brackets , Cell Line , Metal Ceramic Alloys
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