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1.
Ocul Oncol Pathol ; 9(3-4): 101-106, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38046271

RESUMO

Introduction: Ruthenium-106 (Ru-106) brachytherapy is one of the commonest eye-sparing treatments for choroidal melanoma. These patients require long-term surveillance of the treated tumour remnant to ensure there is no local recurrence. New or progressive pigmented lesions in treated eyes are often regarded as suspicious - especially if there are concerns of extra-scleral extension. Case Presentations: We present two cases of posterior choroidal melanoma treated five and 10 years previously with Ru-106. Both cases developed subconjunctival dark/black lesions on the anterior surface of the eye in the quadrant of the conjunctival peritomy during Ru-106 treatment. Both had similar findings on histopathology: black, non-organic, particulate foreign material of varying confluence deposited on elastin and collagen fibres. Energy dispersive X-ray microanalysis confirmed the material contained silver. Discussion: The Ru-106 applicator consists of a radioactive core of Ru-106 encapsulated within pure silver as a radiation shield. During surgical insertion, stainless steel suture needles and forceps can occasionally scratch the applicator's silver eyelets and scatter microscopic particles of elemental silver into the operative field. These particles were likely deposited within the subconjunctival tissues of these patients during brachytherapy administration, leading to localised ocular argyrosis. Iatrogenic ocular argyrosis should be considered in the differential diagnosis of new pigmented lesions in patients treated with Ru-106 brachytherapy. This study is the first to unequivocally identify the cause of some post-brachytherapy ocular surface pigmentation as caused by silver.

2.
Orbit ; : 1-6, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36398700

RESUMO

A 47-year-old female developed a reddish swelling of the right medial canthus over 3 months. On examination, a red, firm mass, involving the right medial canthal and extending into the inferior fornix was present and the globe was displaced upwards and inwards. A staging MRI scan confirmed a lacrimal sac lesion with anterior orbit extension. After an equivocal biopsy, the patient underwent debulking surgery. Histology showed a lacrimal sac invasive adenosquamous carcinoma, comprising poorly differentiated squamous carcinoma and invasive adenocarcinoma areas arranged in a tubulo-glandular pattern. The adenocarcinoma harboured numerous cilia. p16 showed block positivity of both components and micro-dissected tissue from both areas showed the presence of HPV16 DNA by PCR. This is the first description of ciliated adenosquamous carcinoma of the lacrimal sac and this finding is placed into the context of what is known about ciliated head and neck adenosquamous carcinomas and the role of high-risk HPV.

3.
Stem Cell Reports ; 17(7): 1699-1713, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35750043

RESUMO

Conjunctival epithelial cells, which express viral-entry receptors angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine type 2 (TMPRSS2), constitute the largest exposed epithelium of the ocular surface tissue and may represent a relevant viral-entry route. To address this question, we generated an organotypic air-liquid-interface model of conjunctival epithelium, composed of basal, suprabasal, and superficial epithelial cells, and fibroblasts, which could be maintained successfully up to day 75 of differentiation. Using single-cell RNA sequencing (RNA-seq), with complementary imaging and virological assays, we observed that while all conjunctival cell types were permissive to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome expression, a productive infection did not ensue. The early innate immune response to SARS-CoV-2 infection in conjunctival cells was characterised by a robust autocrine and paracrine NF-κB activity, without activation of antiviral interferon signalling. Collectively, these data enrich our understanding of SARS-CoV-2 infection at the human ocular surface, with potential implications for the design of preventive strategies and conjunctival transplantation.


Assuntos
COVID-19 , Células Epiteliais/metabolismo , Humanos , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Receptores Virais/metabolismo , SARS-CoV-2
4.
Haematologica ; 107(8): 1902-1913, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35021601

RESUMO

Germline defects affecting the DNA-binding domain of the transcription factor FLI1 are associated with a bleeding disorder that is characterized by the presence of large, fused α-granules in platelets. We investigated whether the genes showing abnormal expression in FLI1-deficient platelets could be involved in platelet α-granule biogenesis by undertaking transcriptome analysis of control platelets and platelets harboring a DNA-binding variant of FLI1. Our analysis identified 2,276 transcripts that were differentially expressed in FLI1-deficient platelets. Functional annotation clustering of the coding transcripts revealed significant enrichment for gene annotations relating to protein transport, and identified Sorting nexin 24 (SNX24) as a candidate for further investigation. Using an induced pluripotent stem cell-derived megakaryocyte model, SNX24 expression was found to be increased during the early stages of megakaryocyte differentiation and downregulated during proplatelet formation, indicating tight regulatory control during megakaryopoiesis. CRISPR-Cas9 mediated knockout (KO) of SNX24 led to decreased expression of immature megakaryocyte markers, CD41 and CD61, and increased expression of the mature megakaryocyte marker CD42b (P=0.0001), without affecting megakaryocyte polyploidisation, or proplatelet formation. Electron microscopic analysis revealed an increase in empty membrane-bound organelles in SNX24 KO megakaryocytes, a reduction in α-granules and an absence of immature and mature multivesicular bodies, consistent with a defect in the intermediate stage of α-granule maturation. Co-localization studies showed that SNX24 associates with each compartment of α-granule maturation. Reduced expression of CD62P and VWF was observed in SNX24 KO megakaryocytes. We conclude that SNX24 is required for α-granule biogenesis and intracellular trafficking of α-granule cargo within megakaryocytes.


Assuntos
Megacariócitos , Nexinas de Classificação , Humanos , Plaquetas/metabolismo , Grânulos Citoplasmáticos/metabolismo , DNA , Megacariócitos/metabolismo , Transporte Proteico , Nexinas de Classificação/genética , Nexinas de Classificação/metabolismo
5.
Cardiovasc Res ; 118(7): 1835-1848, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34048532

RESUMO

AIMS: Spontaneous coronary artery dissection (SCAD) is a cause of acute coronary syndromes and in rare cases sudden cardiac death (SCD). Connective tissue abnormalities, coronary inflammation, increased coronary vasa vasorum (VV) density, and coronary fibromuscular dysplasia have all been implicated in the pathophysiology of SCAD but have not previously been systematically assessed. We designed a study to investigate the coronary histological and dermal collagen ultrastructural findings in SCAD. METHODS AND RESULTS: Thirty-six autopsy SCAD cases were compared with 359 SCAD survivors. Coronary and myocardial histology and immunohistochemistry were undertaken. Transmission electron microscopy (TEM) of dermal extracellular matrix (ECM) components of n = 31 SCAD survivors and n = 16 healthy volunteers were compared. Autopsy cases were more likely male (19% vs. 5%; P = 0.0004) with greater proximal left coronary involvement (56% vs. 18%; P < 0.0001) compared to SCAD survivors. N = 24 (66%) of cases showed no myocardial infarction on macro- or microscopic examination consistent with arrhythmogenic death. There was significantly (P < 0.001) higher inflammation in cases with delayed-onset death vs. sudden death and significantly more inflammation surrounding the dissected vs. non-dissected vessel segments. N = 17 (47%) cases showed limited intimal fibro-elastic thickening but no features of fibromuscular dysplasia and no endothelial or internal elastic lamina abnormalities. There were no differences in VV density between SCAD and control cases. TEM revealed no general ultrastructural differences in ECM components or markers of fibroblast metabolic activity. CONCLUSIONS: Assessment of SCD requires careful exclusion of SCAD, particularly in cases without myocardial necrosis. Peri-coronary inflammation in SCAD is distinct from vasculitides and likely a reaction to, rather than a cause for SCAD. Coronary fibromuscular dysplasia or increased VV density does not appear pathophysiologically important. Dermal connective tissue changes are not common in SCAD survivors.


Assuntos
Anomalias dos Vasos Coronários , Displasia Fibromuscular , Infarto do Miocárdio , Doenças Vasculares , Tecido Conjuntivo , Angiografia Coronária/métodos , Anomalias dos Vasos Coronários/diagnóstico por imagem , Anomalias dos Vasos Coronários/etiologia , Vasos Coronários , Humanos , Inflamação , Masculino , Infarto do Miocárdio/patologia , Doenças Vasculares/congênito
6.
Ultrastruct Pathol ; 45(6): 414-420, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34538206

RESUMO

Vascular Ehlers-Danlos Syndrome (vEDS) and Osteogenesis Imperfecta (OI) are two forms of connective tissue disorders. Previously, transmission electron microscopy of skin biopsies was routinely performed on all patients who were clinically suspected to have vEDS. At present, molecular genetics using genomic DNA extracted from a blood sample is the first line investigation for these patients. However, when variants of uncertain clinical significance are identified on genetic testing and individuals do not have the classical features of OI or vEDS, additional phenotypic information obtained from a skin biopsy can be valuable for contributing to the evidence for re-classifying pathogenicity of variants.We present a cohort of six patients with molecularly confirmed vEDS and one patient with a severe form of OI, who each had expanded (or dilated), protein-filled, rough endoplasmic reticulum identified on transmission electron microscopy. The patients were identified through retrospective screening of medical records, and biopsies were taken between 1999-2016. We discuss the potential role for assessing rough endoplasmic reticulum expansion as a useful tool to allow further phenotyping of these individuals.


Assuntos
Síndrome de Ehlers-Danlos , Osteogênese Imperfeita , Colágeno Tipo III , Síndrome de Ehlers-Danlos/diagnóstico , Síndrome de Ehlers-Danlos/genética , Retículo Endoplasmático Rugoso , Humanos , Osteogênese Imperfeita/diagnóstico , Osteogênese Imperfeita/genética , Estudos Retrospectivos
7.
Am J Dermatopathol ; 43(11): 822-826, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33606379

RESUMO

ABSTRACT: A case of localized argyria in a 36-year-old female jeweler is described who presented with 2 discrete and asymptomatic bluish-black pigmented macules on the pulp of her left middle finger. A skin biopsy from both lesions demonstrated deposition of brown/black pigmented granules along the basement membrane zone of eccrine glands, blood vessels, nerves, and the dermo-epidermal junction fully in keeping with silver deposition. In addition, there was yellow-brown deposition seen within the interstitial dermis mimicking an early form of ochronosis, so called "pseudo-ochronosis." This latter feature is rarely described in cases of argyria. Transmission electron microscopy and energy dispersive x-ray spectroscopy confirmed the presence of electron dense particles up to 150 nm in diameter and the presence of silver, respectively. On further questioning, the patient had a history of localized and chronic exposure to silver, which specifically involved holding and manipulating silver wires and rings over the left middle finger. This case highlights an unusual and rare presentation of localized argyria in a jeweler. In addition, our case showed preferential silver deposition on dermal elastic fibers which has not been previously described in the literature.


Assuntos
Argiria/patologia , Dermatite Ocupacional/patologia , Joias , Adulto , Argiria/diagnóstico , Argiria/etiologia , Feminino , Dedos , Dermatoses da Mão/induzido quimicamente , Dermatoses da Mão/patologia , Humanos , Ocronose/patologia
8.
Eur J Med Genet ; 63(12): 104095, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33166682

RESUMO

As molecular diagnosis of Osteogenesis Imperfecta has become more accessible, there is an increasing ability to consider additional techniques to undertake deep phenotyping of the patient. In this report, we present the details of a female patient with type I Osteogenesis Imperfecta caused due to a pathogenic COL1A1 variant, who suffered from uterine rupture during labour in her second pregnancy, at age 33. Her presentation, patient journey, and histological results are described. Collagen flowers were identified with electron microscopy of a skin biopsy, and the significance of these are explored. Two other recorded cases of women with Osteogenesis Imperfecta who developed uterine rupture are discussed. This report demonstrates the potential role for ultrastructural tissue examination and deep phenotyping, to allow further insights into the relationship between genotype and phenotype.


Assuntos
Osteogênese Imperfeita/genética , Fenótipo , Ruptura Uterina/genética , Adulto , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Citodiagnóstico/normas , Feminino , Testes Genéticos/normas , Humanos , Osteogênese Imperfeita/diagnóstico , Gravidez , Pele/ultraestrutura , Ruptura Uterina/diagnóstico
9.
Eur J Med Genet ; 63(4): 103798, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31655143

RESUMO

Musculocontractural Ehlers-Danlos syndrome (mcEDS) is an autosomal recessive condition characterized by distinct craniofacial features, multisystem congenital malformations and progressive fragility of connective tissues. It is caused by pathogenic variants in CHST14 and DSE genes. There are three reports of pathogenic variants in DSE in four mcEDS patients. In this study we provide clinical and molecular presentation of two new patients with DSE related mcEDS. Analysing clinical exome data, a homozygous pathogenic DSE variant, c.1150_1157del p.(Pro384Trpfs*9), was identified in a 32 year old man with bilateral congenital talipes equinovarus, characteristic facial features, myopia, hyperextensible skin at the elbows, significant palmar wrinkling, bilateral inguinal hernias and chronic leg, back and joint pain. Electron microscopical examination of skin biopsy showed changes consistent with mild compensatory elastic fibre hypertrophy and mildly loose collagen bundles. The variant is predicted to result in a frameshift and introduction of a premature termination codon in the final exon of the DSE gene, anticipated to lead to the loss of approximately 60% of the normal reading frame. The second patient has a phenotype consistent with previously reported cases of DSE associated musculocontractural EDS. A novel homozygous missense DSE variant of uncertain clinical significance was detected. This case study further delineates the DSE associated mcEDS phenotype and illustrates absence of major cutaneous, cardiovascular, renal and respiratory features, which supports previous suggestions that patients with DSE associated mcEDS present with a milder phenotype compared to those with CHST14 mutations.


Assuntos
Antígenos de Neoplasias/genética , Contratura/patologia , Proteínas de Ligação a DNA/genética , Síndrome de Ehlers-Danlos/genética , Síndrome de Ehlers-Danlos/patologia , Mutação , Proteínas de Neoplasias/genética , Adulto , Variação Biológica da População , Contratura/genética , Humanos , Masculino , Fenótipo
10.
Ocul Oncol Pathol ; 4(2): 100-106, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30320089

RESUMO

BACKGROUND: Infantile capillary hemangiomas (IHs) affect approximately 4-5% of infants. The systemic nonselective ß-adrenergic antagonist, propranolol, has become the standard first-line treatment for severe IHs. The topical ß-antagonist, timolol maleate, has also demonstrated efficacy and safety in treating superficial and some deep capillary hemangiomas. Despite their therapeutic success and prevalent use, the mechanism of action of ß-adrenergic antagonists in the treatment of IHs is not well understood. METHODS: Histopathological and electron microscopic evaluation of two periocular IHs excised at 1 week and 24 months following topical timolol treatment was performed. RESULTS: Distinct morphological differences were observed between spontaneously regressed and ß-antagonist-treated IHs. The former was characterized by diffuse collagen deposition and interstitial fibrosis, while the latter showed organized concentric collagen IV deposition within obliterated vessel lumen, suggestive of waves of endothelial cell apoptosis, leaving behind layers of basement membrane deposits as a stress response. CONCLUSIONS: Based on these observations, we hypothesize that, apart from their well-known cardiac and vasodilatory effects, ß-antagonists could induce endothelial cell apoptosis in IH leading to endovascular occlusion and we present supporting evidence to explain why this response might be specific to hypoxic tissue.

11.
J Med Genet ; 55(3): 158-165, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29263160

RESUMO

BACKGROUND: Cole-Carpenter syndrome (CCS) is commonly classified as a rare Osteogenesis Imperfecta (OI) disorder. This was following the description of two unrelated patients with very similar phenotypes who were subsequently shown to have a heterozygous missense mutation in P4HB. OBJECTIVES: Here, we report a 3-year old female patient with severe OI who on exome sequencing was found to carry the same missense mutation in P4HB as reported in the original cohort. We discuss the genetic heterogeneity of CCS and underlying mechanism of P4HB in collagen production. METHODS: We undertook detailed clinical, radiological and molecular phenotyping in addition, to analysis of collagen in cultured fibroblasts and electron microscopic examination in the patient reported here. RESULTS: The clinical phenotype appears consistent in patients reported so far but interestingly, there also appears to be a definitive phenotypic clue (crumpling metadiaphyseal fractures of the long tubular bones with metaphyseal sclerosis which are findings that are uncommon in OI) to the underlying genotype (P4HB variant). DISCUSSION: P4HB (Prolyl 4-hydroxylase, betasubunit) encodes for PDI (Protein Disulfide isomerase) and in cells, in its tetrameric form, catalyses formation of 4-hydroxyproline in collagen. The recurrent variant in P4HB, c.1178A>G, p.Tyr393Cys, sits in the C-terminal reactive centre and is said to interfere with disulphide isomerase function of the C-terminal reactive centre. P4HB catalyses the hydroxylation of proline residues within the X-Pro-Gly repeats in the procollagen helical domain. Given the inter-dependence of extracellular matrix (ECM) components in assembly of a functional matrix, our data suggest that it is the organisation and assembly of the functional ECM that is perturbed rather than the secretion of collagen type I per se. CONCLUSIONS: We provide additional evidence of P4HB as a cause of a specific form of OI-CCS and expand on response to treatment with bisphosphonates in this rare disorder.


Assuntos
Craniossinostoses/genética , Anormalidades do Olho/genética , Hidrocefalia/genética , Osteogênese Imperfeita/genética , Pró-Colágeno-Prolina Dioxigenase/genética , Isomerases de Dissulfetos de Proteínas/genética , Pré-Escolar , Craniossinostoses/fisiopatologia , Anormalidades do Olho/fisiopatologia , Feminino , Genótipo , Heterozigoto , Humanos , Hidrocefalia/fisiopatologia , Mutação de Sentido Incorreto/genética , Osteogênese Imperfeita/patologia , Osteogênese Imperfeita/fisiopatologia , Linhagem , Fenótipo
12.
Ocul Oncol Pathol ; 3(1): 17-21, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28275598

RESUMO

PURPOSE: To describe the clinical features of a Caucasian female patient with a history of treated gastrointestinal Whipple's disease (WD) who developed new-onset diplopia, with a description of the histopathological features of the extraocular muscle biopsies. METHODS: A previously fit 38-year-old Caucasian female presented with acute-onset diplopia after being on a sustained medication regime for biopsy-proven gastrointestinal WD. A magnetic resonance imaging scan of her orbits with gadolinium revealed diffuse enhancement of the bellies of the extraocular muscles bilaterally, particularly the medial rectus, superior rectus, and superior oblique muscles, consistent with an infiltrative myositis. She underwent unilateral extraocular muscle biopsies. RESULTS: The extraocular muscle biopsies contained macrophages between the muscle fibres. These contained periodic acid-Schiff-positive cytoplasmic granules. Immunohistochemistry with an antibody raised to Tropheryma whipplei showed positive staining of the same macrophages. Transmission electron microscopy confirmed the presence of effete T. whipplei cell membranes in lysosomes. CONCLUSION: This case describes bilateral WD-associated extraocular muscle myositis. The exact mechanism for this unusual presentation is unclear, but both a WD-associated immune reconstitution inflammatory syndrome and treatment failure are possibilities, with a good response observed to antibiotic therapy and adjunctive corticosteroids.

13.
Cerebellum Ataxias ; 4: 1, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28074147

RESUMO

BACKGROUND: Cerebellar ataxia with sensory ganglionopathy is a rare neurological combination that can occur in some hereditary ataxias including mitochondrial diseases and in gluten sensitivity. Individually each condition can be a classic paraneoplastic neurological syndrome. We report a patient with this combination who was diagnosed with light-chain myeloma ten years after initial presentation. CASE PRESENTATION: A 65-year-old Caucasian lady was referred to our Ataxia Clinic because of a 6-year history of progressive unsteadiness and a 2-year history of slurred speech. Past medical history included arterial hypertension. The patient was a non-smoker was not consuming alcohol excessively. There was no family history of ataxia. Neurological examination revealed prominent gaze-evoked nystagmus, heel to shin ataxia, gait ataxia, reduced reflexes and loss of vibration sensation in the legs. Cerebellar ataxia was confirmed using magnetic resonance spectroscopy of the cerebellum and sensory ganglionopathy using neurophysiological assessments including blink reflex study. A muscle biopsy that was arranged to explore the possibility of mitochondrial disease revealed amyloidosis. Urinalysis confirmed the presence of light chains. A bone marrow biopsy confirmed the diagnosis of light chain multiple myeloma. CONCLUSIONS: Whilst it could be argued that this could simply be a coincidence, the rarity of these conditions and the absence of an alternative aetiology for the neurological dysfunction argue in favour of a paraneoplastic phenomenon.

14.
J Hepatol ; 65(6): 1179-1187, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27469900

RESUMO

BACKGROUND & AIMS: Neonatal sclerosing cholangitis (NSC) is a severe neonatal-onset cholangiopathy commonly leading to liver transplantation (LT) for end-stage liver disease in childhood. Liver biopsy findings histopathologically resemble those in biliary atresia (BA); however, in NSC extrahepatic bile ducts are patent, whilst in BA their lumina are obliterated. NSC is commonly seen in consanguineous kindreds, suggesting autosomal recessive inheritance. METHODS: From 29 NSC patients (24 families) identified, DNA was available in 24 (21 families). Thirteen (7 male) patients (12 families) of consanguineous parentage were selected for whole exome sequencing. Sequence variants were filtered for homozygosity, pathogenicity, minor allele frequency, quality score, and encoded protein expression pattern. RESULTS: Four of 13 patients were homozygous and two were compound heterozygous for mutations in the doublecortin domain containing 2 gene (DCDC2), which encodes DCDC2 protein and is expressed in cholangiocyte cilia. Another 11 patients were sequenced: one (with one sibling pair) was compound heterozygous for DCDC2 mutations. All mutations were protein-truncating. In available liver tissue from patients with DCDC2 mutations, immunostaining for human DCDC2 and the ciliary protein acetylated alpha-tubulin (ACALT) showed no expression (n=6) and transmission electron microscopy found that cholangiocytes lacked primary cilia (n=5). DCDC2 and ACALT were expressed in NSC patients without DCDC2 mutations (n=22). Of the patients carrying DCDC2 mutations, one died awaiting LT; five came to LT, of whom one died 2years later. The other 4 are well. CONCLUSION: Among 24 NSC patients with available DNA, 7 had mutations in DCDC2 (6 of 19 families). NSC patients in substantial proportion harbour mutations in DCDC2. Their disease represents a novel liver-based ciliopathy. LAY SUMMARY: Neonatal sclerosing cholangitis (NSC) is a rare genetic form of liver disease presenting in infancy. Through next generation sequencing we identified mutations in the gene encoding for doublecortin domain containing 2 (DCDC2) protein in a group of NSC children. DCDC2 is a signalling and structural protein found in primary cilia of cholangiocytes. Cholangiocytes are the cells forming the biliary system which is the draining system of the liver.


Assuntos
Colangite Esclerosante/genética , Proteínas Associadas aos Microtúbulos/genética , Mutação , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Recém-Nascido , Masculino
15.
Clin Dysmorphol ; 24(2): 45-54, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25436829

RESUMO

Osteogenesis imperfecta (OI) is a heterogeneous group of inherited disorders of bone formation, resulting in low bone mass and an increased propensity for fractures. It is a variable condition with a range of clinical severities. The histological and ultrastructural findings in the skin of patients with OI have not been described in detail in the previously published literature. Although protein analysis of cultured fibroblasts has historically been used in the diagnostic work-up of OI patients, other aspects of skin examination are not routinely performed as part of the diagnostic pathway in patients with OI. The aims of this study were to perform histological and ultrastructural examination of skin biopsies in patients with OI. This was to identify common and distinguishing features in the numerous genetically distinct subtypes of OI and compare the findings with those in patients who did not present with fractures, and to enable the use of the results thus obtained to aid in the diagnostic work-up of patients with OI. As part of a larger research study set-up to identify clinical features and natural history in patients with atypical features of OI, skin biopsy and examination (histology and electron microscopy) were undertaken. Genetic analysis and ancillary investigations were also performed to identify similarities within this group and to differentiate this group from the 'normal' population. At the end of this study, we were able to demonstrate that the histological and electron microscopic findings on a skin biopsy may be an indicator of the likelihood of identifying a pathogenic mutation in type 1 collagen genes. This is because patients with specific findings on examination, such as elastic fibre area fraction (on histological analysis), collagen fibril diameter variability, deviation from the expected mean and collagen flowers (on electron microscopy), are more likely to be positive on genetic analyses. This has, in turn, provided more insight into the pathways to direct gene testing and has reinforced the need for accurate phenotyping before undertaking further genetic investigations. The morphometric assessment of elastic fibre area fraction and ultrastructural findings from this study have provided us with a better understanding of OI and insights into the possible mechanism of these changes in the skin. Correlation of skin findings with the clinical phenotype as well as genetic testing has enabled understanding of the molecular pathogenesis and translation of changes at the genomic level to clinical phenotype.


Assuntos
Osso e Ossos/ultraestrutura , Osteogênese Imperfeita/patologia , Pele/ultraestrutura , Adolescente , Adulto , Biópsia , Osso e Ossos/patologia , Criança , Pré-Escolar , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Feminino , Estudos de Associação Genética , Testes Genéticos , Humanos , Masculino , Mutação , Osteogênese/genética , Osteogênese Imperfeita/genética , Pele/patologia
16.
Nephron Clin Pract ; 124(1-2): 31-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24080738

RESUMO

BACKGROUND AND AIM: Focal segmental glomerulosclerosis (FSGS) is a common cause of idiopathic nephrotic syndrome in adults (35%). A number of genetic and familial forms of FSGS have been recognized. Here, we report a large pedigree with a pathogenic mutation in LMNA (R349W) in which four members were found to have biopsy-proven FSGS. The LMNA gene codes for lamins A and C, major components of the nuclear lamina which function in nuclear architecture, integrity and the regulation of gene expression. METHODS: Pedigree screening and mutation analysis of LMNA gene in all family members. Renal biopsies were performed in proteinuric patients. A molecular 3D model of the familial LMNA mutation was constructed. RESULTS: There were a total of 16 affected members from four generations, 12 of whom were found to carry the germline LMNA mutation. All affected adults had clinical features of familial partial lipodystrophy (FPLD) of the non-Dunnigan variety. Four patients within the same generation presented with a variable degree of renal impairment and proteinuria. Renal biopsies from all four revealed FSGS. The familial mutation is a missense change (R349W) in exon 6 of LMNA (c.1045C>T). CONCLUSIONS: We report a genetic link between LMNA and biopsy-proven FSGS in a large pedigree with FPLD. This unexpected association extends the disease spectrum of LMNA to the kidney and suggests that the physiological role of LMNA could be relevant to the maintenance of glomerular structure and function.


Assuntos
Glomerulosclerose Segmentar e Focal/diagnóstico , Glomerulosclerose Segmentar e Focal/genética , Lamina Tipo A/genética , Lipodistrofia Parcial Familiar/diagnóstico , Lipodistrofia Parcial Familiar/genética , Adulto , Feminino , Humanos , Masculino , Mutação/genética , Linhagem
17.
Clin Dysmorphol ; 22(3): 93-101, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23612438

RESUMO

Type V osteogenesis imperfecta (OI) presents with moderate-to-severe skeletal deformity and is characterized by hyperplastic callus formation at fracture sites and calcification of the interosseous membranes of the forearm and lower leg. The facial dysmorphism is not well characterized and has not been described in previous reports. Inheritance is autosomal dominant, although the genetic aetiology remained unknown until very recently. The aims of this study were to establish the genetic aetiology in patients with type V OI and further characterize patients with this condition, and to ascertain whether they have a similar clinical phenotype and facial dysmorphism. Three families (one mother-daughter pair and two singletons) were identified with the above features and further investigations (molecular genetic analysis and skin biopsy including electron microscopy, histology and collagen species analysis) were performed. Accurate phenotyping of patients with type V OI was performed. PCR amplification was performed using the Sheffield Diagnostic Genetics Service pyrosequencing assay for the interferon-induced transmembrane protein-5 (IFITM5) gene. All the patients had been confirmed to have a heterozygous variant, c.[-14C>T];[=], in the 5'-UTR of the IFITM5 gene, which is located in the transcribed region of this gene. This recurrent mutation, in IFITM5, also known as bone-restricted interferon-induced transmembrane protein-like protein or BRIL, encodes a protein with a function in bone formation and plays an important role in osteoblast formation. All four patients in this study appear to have similar clinical features and facial dysmorphism, including a short, up-turned nose, a small mouth, a prominent chin and greyish-blue sclerae. Skin biopsy in one patient showed clumping of elastic fibres and normal biochemical analysis of collagen. We have been able to characterize patients with type V OI further and confirm the genetic aetiology in this distinct form of OI. Accurate phenotyping (including describing the common facial features) before investigations is important to enable the useful interpretation of genetic results and/or target-specific gene testing.


Assuntos
Osso e Ossos/anormalidades , Fácies , Proteínas de Membrana/genética , Osteogênese Imperfeita/genética , Regiões 5' não Traduzidas/genética , Adulto , Calcificação Fisiológica/genética , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Osteoblastos/metabolismo , Osteogênese Imperfeita/diagnóstico , Fenótipo
18.
Radiology ; 263(1): 107-16, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22344402

RESUMO

PURPOSE: To detect the ultrastructural site of gadolinium retention in skin by using an animal model of nephrogenic systemic fibrosis and compare a linear, low-stability gadolinium chelate (formulated gadodiamide) with a macrocylic, high-stability gadolinium chelate (gadoterate meglumine). MATERIALS AND METHODS: Experimental procedures were performed according to rules and regulations laid down by the UK Home Office (Animal Procedures Act of 1986). Male Wistar rats were subjected to 5/6 subtotal nephrectomy (creatinine clearance, 25% normal). Gadolinium-based contrast agents, formulated gadodiamide (n = 9) and gadoterate meglumine (n = 11), were administered intravenously (2.5 mmol/kg for 5 days). After 28 days, skin was analyzed by means of morphometric and immunohistochemical techniques and electron microscopy. Data were compared with the Student t test. Skin gadolinium was located by means of energy-filtered transmission electron microscopy. RESULTS: Formulated gadodiamide produced a 40-fold greater increase in gadolinium in skin than did gadoterate meglumine. An electron-dense filamentous material, detected within extracellular matrix, displayed a "halo" appearance, associated with collagen fibrils and electron-dense intracellular fragments of collagen fibrils within activated fibroblasts. Both electron-dense features demonstrated the presence of gadolinium but were much less apparent following gadoterate meglumine administration, where the presence of gadolinium was not detected. Formulated gadodiamide increased dermal cell count, dermal thickness, and collagen bundle density with enhanced immunostain for CD34, fibroblast-specific protein 1,4-hydroxy-prolyl-hydroxylase, and factor XIIIa. Circular staining for α-smooth muscle actin indicated new blood vessel formation. Skin of rats receiving gadoterate meglumine remained unchanged. CONCLUSION: Gadolinium retention in skin following formulated gadodiamide administration was located to the collagen fibril, in both the extracellular matrix and within activated fibroblasts.


Assuntos
Meios de Contraste/toxicidade , Gadolínio DTPA/toxicidade , Meglumina/toxicidade , Dermopatia Fibrosante Nefrogênica/induzido quimicamente , Compostos Organometálicos/toxicidade , Pele/metabolismo , Animais , Meios de Contraste/administração & dosagem , Modelos Animais de Doenças , Gadolínio DTPA/administração & dosagem , Técnicas Imunoenzimáticas , Masculino , Meglumina/administração & dosagem , Microscopia Eletrônica de Transmissão , Compostos Organometálicos/administração & dosagem , Ratos , Ratos Wistar , Espectrofotometria Atômica
19.
Hepatology ; 56(2): 735-46, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22334567

RESUMO

UNLABELLED: Acetaminophen-induced acute liver failure (AALF) is associated with innate immunity activation, which contributes to the severity of hepatic injury and clinical outcome. A marked increase in hepatic macrophages (h-mφ) is observed in experimental models of AALF, but controversy exists regarding their role, implicating h-mφ in both aggravation and resolution of liver injury. The role of h-mφ in human AALF is virtually unexplored. We sought to investigate the role of chemokine (C-C motif) ligand 2 (CCL2) in the recruitment of circulating monocytes to the inflamed liver and to determine how the h-mφ infiltrate and liver microenvironment may contribute to tissue repair versus inflammation in AALF. We evaluated circulating monocytes, their chemokine (C-C motif) receptor 2 (CCR2) expression, and serum CCL2 levels in patients with AALF. Cell subsets and numbers of circulation-derived (MAC387+) or resident proliferating (CD68/Ki67+) h-mφ in hepatic immune infiltrates were determined by immunohistochemistry. Inflammatory cytokine levels were determined in whole and laser microdissected liver tissue by proteome array. In AALF, circulating monocytes were depleted, with the lowest levels observed in patients with adverse outcomes. CCL2 levels were high in AALF serum and hepatic tissue, and circulating monocyte subsets expressed CCR2, suggesting CCL2-dependent hepatic monocyte recruitment. Significant numbers of both MAC387+ and CD68+ h-mφ were found in AALF compared with control liver tissue with a high proportion expressing the proliferation marker Ki67. Levels of CCL2, CCL3, interleukin (IL)-6, IL-10, and transforming growth factor-ß1 were significantly elevated in AALF liver tissue relative to chronic liver disease controls. CONCLUSION: In AALF, the h-mφ population is expanded in areas of necrosis, both through proliferation of resident cells and CCL2-dependent recruitment of circulating monocytes. The presence of h-mφ within an anti-inflammatory/regenerative microenvironment indicates that they are implicated in resolution of inflammation/tissue repair processes during AALF.


Assuntos
Acetaminofen/intoxicação , Doença Hepática Induzida por Substâncias e Drogas/patologia , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/patologia , Macrófagos/patologia , Adulto , Analgésicos não Narcóticos/intoxicação , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Quimiocina CCL2/metabolismo , Quimiocina CCL3/metabolismo , Quimiotaxia/imunologia , Feminino , Humanos , Interleucina-10/metabolismo , Interleucina-8/metabolismo , Antígeno Ki-67/metabolismo , Falência Hepática Aguda/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/metabolismo , Monócitos/patologia , Receptores CCR2/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
20.
Nephrol Dial Transplant ; 24(12): 3732-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19596742

RESUMO

BACKGROUND: Morbid obesity represents a major health problem with increasing incidence worldwide. The clinical manifestation of renal involvement in obesity is proteinuria, and the histological feature is glomerulomegaly with or without focal and segmental glomerulosclerosis (FSGS). In this study, we have investigated the very early histological changes in kidneys of people with morbid obesity and no proteinuria. Patients and methods. Eighteen patients with body mass index (BMI) >50 kg/m(2) who underwent a variant of biliopancreatic diversion with Roux-en-Y reconstruction (BPD-RYGBP) and consented to undergo a renal biopsy during the surgical procedure were included in the study. The estimation of early histological changes was performed on light (n = 18) and electron microscopy (n = 13). RESULTS: The mean glomerular cross-sectional area was 30 943 +/- 10,984 microm(2) that is higher than that observed in non-obese individuals. In 21% of the examined glomeruli, the glomerular planar surface area (GPSA) was >40,000 microm(2). Thickening of the glomerular basement membrane (GBM) and scattered paramesangial deposits were identified in 9 of 13 patients (70%) whose renal tissue was examined by electron microscopy. A reduction in the slit pore frequency was observed in obese patients due to extensive foot process effacement. Significant positive correlations between mean GPSA and body weight (r = 0.462, P = 0.05), and between GBM thickness and HbA1c, serum total cholesterol and triglyceride levels (r = 0.60, P = 0.05; r = 0.789, P = 0.004; r = 0.70, P = 0.016, respectively), were observed. CONCLUSIONS: Glomerulomegaly as well as histological lesions resembling those of early diabetic nephropathy are observed in kidney biopsies of patients with morbid obesity even before the appearance of microalbuminuria. The potential regression of these changes after weight loss needs to be clarified.


Assuntos
Rim/patologia , Obesidade Mórbida/patologia , Adulto , Feminino , Humanos , Masculino , Fatores de Tempo
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