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Cysteamine is currently the only therapy for nephropathic cystinosis. It significantly improves life expectancy and delays progression to end-stage kidney disease; however, it cannot prevent it. Unfortunately, compliance to therapy is often weak, particularly during adolescence. Therefore, finding better treatments is a priority in the field of cystinosis. Previously, we found that genistein, an isoflavone particularly enriched in soy, can revert part of the cystinotic cellular phenotype that is not sensitive to cysteamine in vitro. To test the effects of genistein in vivo, we fed 2-month-old wild-type and Ctns-/- female mice with either a control diet, a genistein-containing diet or a cysteamine-containing diet for 14 months. Genistein (160 mg/kg/day) did not affect the growth of the mice or hepatic functionality. Compared with untreated mice at 16 months, Ctns-/- mice fed with genistein had lower cystine concentrations in their kidneys, reduced formation of cystine crystals, a smaller number of LAMP1-positive structures and an overall better-preserved parenchymal architecture. Cysteamine (400 mg/kg/day) was efficient in reverting the lysosomal phenotype and in preventing the development of renal lesions. These preclinical data indicate that genistein ameliorates kidney injury resulting from cystinosis with no side effects. Genistein therapy represents a potential treatment to improve the outcome for patients with cystinosis.
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Cistinose , Nefropatias , Animais , Feminino , Camundongos , Cisteamina/uso terapêutico , Cistina/uso terapêutico , Cistinose/tratamento farmacológico , Cistinose/genética , Modelos Animais de Doenças , Genisteína/farmacologia , Genisteína/uso terapêutico , RimRESUMO
Seventeen out of 764 liver biopsies from transplanted (Tx) livers in children showed glycogen-ground glass (GGG) hepatocytic inclusions. The inclusions were not present in pre-Tx or in the explanted or donor's liver. Under the electron microscope (EM), the stored material within the cytosol appeared as non-membrane-bound aggregates of electron-lucent globoid or fibrillar granules, previously described as abnormally structured glycogen and identified as Polyglucosan bodies (PB). The appearance of GGG in our children was analogous to that of PB-GGG occurring in a number of congenital diseases due to gene mutations such as Lafora's d., Andersen's d., Adult Polyglucosan Body Disease and glycogenin deficiency. The same type of GGG was previously reported in the liver of patients undergoing transplants, immunosuppressive or antiblastic treatment. To explore the potential mechanism of GGG formation, we examined whether the drugs after whose treatment this phenomenon was observed could have a role. By carrying out molecular docking, we found that such drugs somehow present a high binding affinity for the active region of glycogenin, implicating that they can inactivate the protein, thus preventing its interaction with glycogen synthase (GS), as well as the maturation of the nascent glycogen towards gamma, beta or alfa glycogen granules. We could also demonstrate that PG inclusions consist of a complex of PAS positive material (glycogen) and glycogen-associated proteins, i.e., glicogenin-1 and -2 and ubiquitin. These features appear to be analogous to congenital GGG, suggesting that, in both cases, they result from the simultaneous dysregulation of glycogen synthesis and degradation. Drug-induced GGG appear to be toxic to the cell, despite their reversibility.
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Transplante de Fígado , Criança , Glucanos/metabolismo , Glicogênio/metabolismo , Humanos , Simulação de Acoplamento MolecularRESUMO
Recessive mutations in the CTNS gene encoding the lysosomal transporter cystinosin cause cystinosis, a lysosomal storage disease leading to kidney failure and multisystem manifestations. A Ctns knockout mouse model recapitulates features of cystinosis, but the delayed onset of kidney manifestations, phenotype variability and strain effects limit its use for mechanistic and drug development studies. To provide a better model for cystinosis, we generated a Ctns knockout rat model using CRISPR/Cas9 technology. The Ctns-/- rats display progressive cystine accumulation and crystal formation in multiple tissues including kidney, liver and thyroid. They show an early onset and progressive loss of urinary solutes, indicating generalized proximal tubule dysfunction, with development of typical swan-neck lesions, tubulointerstitial fibrosis and kidney failure, and decreased survival. The Ctns-/- rats also present crystals in the cornea, and bone and liver defects, as observed in patients. Mechanistically, the loss of cystinosin induces a phenotype switch associating abnormal proliferation and dedifferentiation, loss of apical receptors and transporters, and defective lysosomal activity and autophagy in the cells. Primary cultures of proximal tubule cells derived from the Ctns-/- rat kidneys confirmed the key changes caused by cystine overload, including reduced endocytic uptake, increased proliferation and defective lysosomal dynamics and autophagy. The novel Ctns-/- rat model and derived proximal tubule cell system provide invaluable tools to investigate the pathogenesis of cystinosis and to accelerate drug discovery.
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Sistemas de Transporte de Aminoácidos Neutros , Cistinose , Síndrome de Fanconi , Insuficiência Renal , Sistemas de Transporte de Aminoácidos Neutros/genética , Animais , Autofagia/genética , Cistina , Cistinose/genética , Cistinose/patologia , Lisossomos/metabolismo , Camundongos , RatosRESUMO
AIM: Median raphe cyst are uncommon malformations of male genitalia, in which are rarely described melanin pigments or melanocytes; less than ten cases have been reported in literature. The aim of our study is to describe a rare ormations, case of pigmented median raphe cyst of the scrotum, successfully treated in our hospital. CASE EXPERIENCE: A 6-years-old boy underwent surgical removal of a melanocytic lesion of the ventral surface of the scrotum in Day Surgery regimen. He reported no surgical complication or recurrence. RESULTS: Histology showed multiple cystic nodules, lined by squamous and pluri-stratified columnar epithelium, some of which contained melanic deposits and were anti-MART-positive. DISCUSSION: Even though the first case has been reported in 1985, the etiology of median raphe cysts remains unclear. Infrequently associated with trauma or infections, these lesions seem to origin from an abnormal development of the periurethral glands or atypical closure of the median raphe. Rarely melanin pigments or melanocytes are described in the histological examination, and the cause of the pigmentation is still unknown. CONCLUSION: Median raphe cysts present a non-negligible variety of clinical presentations and histological features. Pigmented ones represent the rarest form: further studies may be necessary to clarify their pathogenesis and describe their clinical evolution. KEY WORDS: Median raphs, Male genitalia, Malformations.
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Cistos , Escroto , Criança , Humanos , Masculino , Procedimentos Cirúrgicos Ambulatórios , Cistos/diagnóstico , Cistos/cirurgia , Cistos/patologia , Melaninas , Escroto/patologia , Escroto/cirurgia , Uretra/patologia , Uretra/cirurgiaRESUMO
The rare nevus sebaceous (NS) syndrome (NSS) includes cortical malformations and drug-resistant epilepsy. Somatic RAS-pathway genetic variants are pathogenetic in NS, but not yet described within the brain of patients with NSS. We report on a 5-year-old boy with mild psychomotor delay. A brown-yellow linear skin lesion suggestive of NS in the left temporo-occipital area was evident at birth. Epileptic spasms presented at aged six months. EEG showed continuous left temporo-occipital epileptiform abnormalities. Brain MRI revealed a similarly located diffuse cortical malformation with temporal pole volume reduction and a small hippocampus. We performed a left temporo-occipital resection with histopathological diagnosis of focal cortical dysplasia type Ia in the occipital region and hippocampal sclerosis type 1. Three years after surgery, he is seizure-and drug-free (Engel class Ia) and showed cognitive improvement. Genetic examination of brain and skin specimens revealed the c.35G > T (p.Gly12Val) KRAS somatic missense mutation. Literature review suggests epilepsy surgery in patients with NSS is highly efficacious, with 73% probability of seizure freedom. The few histological analyses reported evidenced disorganized cortex, occasionally with cytomegalic neurons. This is the first reported association of a KRAS genetic variant with cortical malformations associated with epilepsy, and suggests a possible genetic substrate for hippocampal sclerosis.
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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BACKGROUND: Treatment of post-transplant focal segmental glomerulosclerosis (FSGS) recurrence is still debated. The use of the fully human anti-CD20 monoclonal antibody ofatumumab has been suggested. CASE-DIAGNOSIS/TREATMENT: Two boys with FSGS received a kidney transplantation at the age of 15 years from a deceased and a living donor. Maintenance therapy consisted of calcineurin inhibitors, antiproliferative agents, and prednisone. Early post-transplant FSGS recurrence was observed after 2 and 3 days. Rituximab infusion and plasmapheresis sessions were performed with transient clinical improvement in the first patient, and no apparent response in the second patient. Both patients were treated with two ofatumumab infusions, which induced in patient #1 a complete and stable remission for more than 12 months and in patient #2 a partial remission with a progressive reduction of proteinuria and normalization of serum protein levels. CONCLUSIONS: Ofatumumab may be a therapeutic option for post-transplant FSGS recurrence in patients who respond poorly to rituximab.
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Anticorpos Monoclonais Humanizados/uso terapêutico , Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Glomerulosclerose Segmentar e Focal/cirurgia , Imunossupressores/uso terapêutico , Transplante de Rim , Adolescente , Humanos , Masculino , RecidivaRESUMO
Medulloblastoma with extensive nodularity (MBEN) is one of the few central nervous system (CNS) tumor entities occurring in infants which is traditionally associated with good to excellent prognosis. Some MBEN, however, have been reported with an unfavorable clinical course. We performed an integrated DNA/RNA-based molecular analysis of a multi-institutional MBEN cohort (n = 41) to identify molecular events which might be responsible for variability in patients' clinical outcomes. RNA sequencing analysis of this MBEN cohort disclosed two clear transcriptome clusters (TCL) of these CNS tumors: "TCL1 MBEN" and "TCL2 MBEN" which were associated with various gene expression signatures, mutational landscapes and, importantly, prognosis. Thus, the clinically unfavorable "TCL1 MBEN" subset revealed transcriptome signatures composed of cancer-associated signaling pathways and disclosed a high frequency of clinically relevant germline PTCH1/SUFU alterations. In contrast, gene expression profiles of tumors from the clinically favorable "TCL2 MBEN" subgroup were associated with activation of various neurometabolic and neurotransmission signaling pathways, and germline SHH-pathway gene mutations were extremely rare in this transcriptome cluster. "TCL2 MBEN" also revealed strong and ubiquitous expression of VSNL1 (visinin-like protein 1) both at the mRNA and protein level, which was correlated with a favorable clinical course. Thus, combining mutational and epigenetic profiling with transcriptome analysis including VSNL1 immunohistochemistry, MBEN patients could be stratified into clinical risk groups of potential value for subsequent treatment planning.
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Biomarcadores Tumorais/metabolismo , Neoplasias Cerebelares/genética , Meduloblastoma/genética , Neurocalcina/metabolismo , Adolescente , Neoplasias Cerebelares/patologia , Criança , Pré-Escolar , Feminino , Perfilação da Expressão Gênica , Humanos , Lactente , Recém-Nascido , Masculino , Meduloblastoma/patologia , Prognóstico , TranscriptomaRESUMO
BACKGROUND: Several cases of severe antibody-mediated rejection (AMR) secondary to antibodies against the angiotensin II type 1 receptor (AT1R-Ab) have been described with variable outcome. CASE-DIAGNOSIS/TREATMENT: We report the case of a 13-year-old boy whose first kidney transplant failed due to steroid-resistant acute cellular rejection, with the subsequent development of sensitization. He received a second kidney transplant which was complicated by early humoral rejection, with weakly positive staining for the complement degradation product C4d. Test results were negative for donor-specific antibodies against human leukocyte antigens (HLA-DSA) and MHC class I-related chain A (MICA) but positive for AT1R-Ab. Retrospective testing of the sera collected during the first kidney transplant was also positive for AT1R-Ab. We therefore hypothesized that the failure of the first transplant was secondary to the same cause. Losartan was immediately introduced into the therapeutic regimen, and the patient showed an excellent clinical and histological recovery. CONCLUSIONS: Testing for AT1R-Ab in any hypertensive patient with acute rejection who tests negative or weakly positive for C4d and negative for HLA-DSA and who is refractory to therapy is highly advisable. Pre-transplant AT1R-Ab may be indicative of the outcome in patients whose first transplant failed. Prompt initiation of treatment with losartan-immediately after transplantation in patients with pre-existing AT1R-Ab-should be encouraged.
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Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/fisiopatologia , Transplante de Rim , Receptor Tipo 1 de Angiotensina/imunologia , Adolescente , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Autoanticorpos/imunologia , Rejeição de Enxerto/patologia , Humanos , Imunidade Humoral , Rim/patologia , Losartan/uso terapêutico , MasculinoAssuntos
Neoplasias Esofágicas/patologia , Junção Esofagogástrica/patologia , Pólipos/patologia , Neoplasias Gástricas/patologia , Pré-Escolar , Endoscopia Gastrointestinal/métodos , Neoplasias Esofágicas/cirurgia , Feminino , Humanos , Pólipos/cirurgia , Neoplasias Gástricas/cirurgia , Tomografia Computadorizada por Raios XRESUMO
Medulloblastoma (MB) is the most common malignant brain tumor in children. Despite therapeutic advancements, high-risk groups still present significant mortality. A deeper knowledge of the signaling pathways contributing to MB formation and aggressiveness would help develop new successful therapies. The target of rapamycin, mTOR signaling, is known to be involved in MB and is already targetable in the clinical setting. Furthermore, mTOR is a master metabolic regulator able to control cell growth versus autophagy decisions in conditions of amino-acid deprivation that can be due to IDO1 enzymatic activity. IDO1 has been also implicated in the regulation of inflammation, as well as of T cell-mediated immune responses, in a variety of pathological conditions, including brain tumors. In particular, IDO1 induces expansion of regulatory T-cells (Treg), preventing immune response against tumor cells. Analysis of 27 MB tissue specimens for the expression of both mTOR and IDO1 showed their widespread expression in all samples. Testing their cooperation in vitro, a significant involvement of IDO1 in mTOR immunogenic pathway was found, able to counteract the aim of rapamycin treatment. In MB cell lines, inhibition of mTOR strongly induced IDO1 expression and activity, corroborating its ability to recruit Treg cells in the tumor microenvironment. The mTOR/IDO1 cross talk was found to be strictly specific of MB cells. We demonstrated that mTOR pathway cross talks with IDO1 pathway to promote MB immune escape, possibly contributing to failure of mTOR- targeted therapy.
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Neoplasias Cerebelares/genética , Resistencia a Medicamentos Antineoplásicos/genética , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Meduloblastoma/genética , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/genética , Antibióticos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/metabolismo , Criança , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Lactente , Meduloblastoma/tratamento farmacológico , Meduloblastoma/metabolismo , Terapia de Alvo Molecular , Transdução de Sinais/efeitos dos fármacos , Sirolimo/uso terapêutico , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologiaRESUMO
The presence of the Y chromosome in the karyotype of patients with disorders of sex differentiation is significantly associated with an increased risk to develop specific types of malignancies, predominantly type II germ cell tumors (GCTs). Gonadoblastoma in the gonads without an obvious testicular differentiation and intratubular germ cell neoplasia of unclassified type in testicular tissue are the precursor lesions of most GCTs. Gonadal dysgenesis, the characteristic feature of Ullrich-Turner syndrome (UTS), further contributes to increase this tumor risk. The reported incidence of Y chromosome material in UTS is 6 to 8% and in these cases an early gonadectomy is strongly recommended to prevent the risk of a malignancy. The aim of this work was to retrospectively analyze the clinical outcome and the histopathological and cytogenetic findings of our UTS patients who underwent gonadectomy to establish strict selection criteria aimed at promoting an organ-sparing surgery.
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Cromossomos Humanos Y/genética , Disgerminoma/patologia , Gonadoblastoma/patologia , Gônadas/cirurgia , Neoplasias Ovarianas/patologia , Síndrome de Turner/complicações , Síndrome de Turner/genética , Adolescente , Proteínas de Ciclo Celular/genética , Criança , Cromossomos Humanos Y/ultraestrutura , Disgerminoma/genética , Disgerminoma/cirurgia , Feminino , Predisposição Genética para Doença , Gonadoblastoma/complicações , Gonadoblastoma/genética , Gonadoblastoma/cirurgia , Gônadas/patologia , Humanos , Cariotipagem , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/cirurgia , Procedimentos Cirúrgicos Profiláticos , Estudos Retrospectivos , Fatores de Risco , Fatores de Transcrição SOXB1/genética , Síndrome de Turner/patologiaRESUMO
Pituicytoma is a tumor extremely rare in childhood, with only 4 cases reported in literature. It is thought to arise from the specialized glial elements called "pituicytes." The association of pituicytoma and Cushing's disease (CD) has been described only once so far, in an adult patient. A 7-year-old girl was referred for clinical signs of hypercortisolism, and a diagnosis of CD was made. MRI revealed 2 pathologic areas in the pituitary gland. The patient underwent surgery, with microscopic transsphenoidal approach, and a well-circumscribed area of pathologic tissue was identified and removed. Surprisingly, histologic and immunohistochemical study provided unequivocal evidence of pituicytoma. No pituitary adenoma could be identified. For persistent hypercortisolism, the patient necessitated transsphenoidal endoscopic reintervention and 2 other lesions were removed. By immunohistological examination, these lesions were confirmed to be corticotropin-secreting adenoma. Unfortunately, there was no postoperative decrease in corticotropin and cortisol levels, and the patient underwent bilateral laparoscopic adrenalectomy. Considering that we report a second case of association of pituicytoma and corticotropin-secreting adenoma, that CD is infrequent, and pituicytoma is extremely rare in childhood, the coexistence of these 2 tumors should not be considered a mere coincidence. To date, there is no conclusive evidence about the origin of these different subtypes of pituitary tumors. This case supports the hypothesis that these tumors share a common progenitor cell, which could be the folliculostellate cell.
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Adenoma/diagnóstico , Hipersecreção Hipofisária de ACTH/etiologia , Neoplasias Hipofisárias/diagnóstico , Adenoma Hipofisário Secretor de ACT/complicações , Adenoma Hipofisário Secretor de ACT/diagnóstico , Adenoma/complicações , Criança , Feminino , Humanos , Hipersecreção Hipofisária de ACTH/diagnóstico , Neoplasias Hipofisárias/complicaçõesRESUMO
Hemiconvulsion-Hemiplegia (HH) syndrome represents an uncommon consequence of prolonged unilateral clonic or hemiconvulsive status epilepticus in childhood, usually occurring during a febrile illness, followed by ipsilateral hemiplegia. The subsequent appearance of focal seizures configures the so called Hemiconvulsion-Hemiplegia-Epilepsy (HHE) syndrome. The pathogenesis of HH/HHE syndrome is still unclear. We describe the case of a 4 year-old girl with congenital adrenal hyperplasia (CAH) whom developed HH/HHE syndrome with drug resistant seizures at the age of 21 months and underwent left cerebral hemispherotomy at the age of 3 years and 6 months. Histopathological findings showed the presence of an underlying inflammatory-degenerative process. Disregulation of the inflammatory cascade has been proposed as one of the possible pathogenetic mechanisms underlying HH/HHE syndrome. To our knowledge however, this is the first report of an association with a histologically documented inflammatory process. The clinical and histopathological findings of our reported case lend support to the possible role of inflammation in the pathogenesis of HH/HHE syndrome.
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Hiperplasia Suprarrenal Congênita/patologia , Encéfalo/patologia , Epilepsias Parciais/patologia , Hemiplegia/patologia , Inflamação/patologia , Hiperplasia Suprarrenal Congênita/complicações , Hiperplasia Suprarrenal Congênita/diagnóstico , Pré-Escolar , Epilepsias Parciais/diagnóstico , Feminino , Hemiplegia/complicações , Hemiplegia/diagnóstico , Humanos , Inflamação/diagnósticoRESUMO
Testicular infarction is an uncommon finding in paediatric age and is usually due to testicular torsion or trauma causing venous rupture with thrombosis and/or arteriolar obstruction. Other causes of segmental infarction of the testes are represented by polyarteritis nodosa, thromboangioiitis obliterans and hypersensitivity angiitis. A few cases of testicular infarction due to epididymitis have been described in the literature related mainly to adult patients. Epididymitis is usually treated in the outpatient setting with close follow-up, but according to our present experience, and reviewing the literature, there may be some cases in which, surgical exploration is mandatory in order to avoid testicular damage.
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Epididimite/complicações , Hemorragia/etiologia , Infarto/etiologia , Testículo/irrigação sanguínea , Humanos , Lactente , MasculinoRESUMO
INTRODUCTION: Microscopic neoplastic thrombosis (MNT) is reported to occur frequently in Wilms tumour (WT). The aim of this study is to determine whether MNT influences prognosis in localised WT. PATIENTS AND METHODS: Records and slides of 80 consecutive, unselected, localised WT patients were retrospectively reviewed. All patients received chemotherapy before surgery according to SIOP Protocol. The median follow-up was 9 years (range 0.5-25.8). The Kaplan-Meier method and the Cox proportional hazard model were applied. RESULTS: MNT was present in 14 (18%) cases. Out of 14 patients with MNT, 6 presented macroscopic thrombosis and 5 had either blastemal predominance or anaplastic histology. The 5-year overall survival (OS) and progression-free survival (PFS) for the whole population were 95% (95% confidence interval, CI, 87-98%) and 91% (95% CI 82-96%), respectively. The 5-year OS and PFS for MNT positive patients were 92% (95% CI 57-99%) and 77% (95% CI 44-92%), while the 5-year OS and PFS for MNT negative patients were 96% (95% CI 87-99%) and 94% (95% CI 85-98%), respectively; the difference was statistically significant (p<0.05) for PFS. In multivariate analysis, only the presence of anaplasia retained significance with a hazard ratio (HR) of 14.8 and 12.9 (p<0.05) for recurrence and death, respectively. CONCLUSION: These data suggest that the presence of MNT increases the risk of recurrence. MNT is associated with well-known prognostic factors, such as macroscopic thrombosis (possibly representing regression of macroscopic involvement) and anaplasia. Further prospective studies are needed to clarify the role of MNT as independent prognostic factor.
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Neoplasias Renais/complicações , Trombose/etiologia , Tumor de Wilms/complicações , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , Dactinomicina/uso terapêutico , Feminino , Humanos , Lactente , Estimativa de Kaplan-Meier , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Masculino , Células Neoplásicas Circulantes , Estudos Retrospectivos , Trombose/patologia , Resultado do Tratamento , Vincristina/uso terapêutico , Tumor de Wilms/tratamento farmacológico , Tumor de Wilms/patologiaRESUMO
We report hypofibrinogenemia and massive hepatic storage of fibrinogen in a child with cryptogenic chronic liver disease. Fibrinogen gene analysis revealed a de novo Aguadilla (c.1201C>T; p.Arg375Trp) mutation. This mutation should be considered in childhood hypofibrinogenemia associated with chronic liver disease.
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Afibrinogenemia/genética , Fibrinogênio/genética , Fibrinogênio/metabolismo , Fígado/metabolismo , Mutação , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Criança , Consanguinidade , Humanos , Masculino , Tempo de Tromboplastina Parcial , Tempo de Protrombina , gama-Glutamiltransferase/sangueRESUMO
Closure of the ductus arteriosus (DA) is due to functional constriction followed by wall remodeling, with neointimal formation caused by proliferation and migration of smooth muscle cells (SMCs) from the media to subendothelium. CD44 is a surface cell proteoglycan family. Its isoform, CD44-v6, is only minimally expressed in SMCs in the media of normal arteries, but is highly expressed in SMCs in the intima and media of injured arteries (e.g., atherosclerosis). Twenty-two autopsy DA specimens, 11 from full-term babies (age range 2 days to 5 months) and 11 from premature babies (age range 3 days to 5 months), with varying degrees of ductal wall remodeling, were evaluated by immunohistochemistry using antiactin, antifibronectin-extradomain A, anti-leukocyte common antigen, anti-CD44, and anti-CD44-v6. In DA with wall remodeling, synthetic antifibronectin-extradomain A-positive SMCs were evident at the neointimal mounds, and the SMCs were highly positive for the CD44-v6 isoform, irrespective of gestational age at birth. Conversely, SMCs of either closed DAs or persistently patent DAs were CD44-v6 negative. In conclusion, the present data provide evidence that closure of DA involves synthetic SMCs highly positive for CD44-v6, and patent or closed DAs are populated by CD44-v6-negative SMCs.
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Permeabilidade do Canal Arterial/metabolismo , Canal Arterial/metabolismo , Glicoproteínas/metabolismo , Receptores de Hialuronatos/metabolismo , Doenças do Prematuro/metabolismo , Miócitos de Músculo Liso/metabolismo , Canal Arterial/crescimento & desenvolvimento , Canal Arterial/patologia , Permeabilidade do Canal Arterial/patologia , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/patologia , Desenvolvimento Muscular/fisiologia , Túnica Íntima/crescimento & desenvolvimento , Túnica Íntima/metabolismo , Túnica Íntima/patologia , Túnica Média/crescimento & desenvolvimento , Túnica Média/metabolismo , Túnica Média/patologiaRESUMO
Deletion 22q11.2 is a chromosomal abnormality detected in young patients with clinical manifestations of the DiGeorge/velocardiofacial syndrome. Conotruncal heart defects are also associated with del22q11.2. An association of these cardiac malformations with neoplasias has been observed. Our series includes two cases of malignancies, a hepatoblastoma and a renal-cell carcinoma, arising in children with complex cardiac malformations. The aim of the study was to determine if the deletion at 22q11.2 was present and could be responsible for both pathological processes. Del22q11.2 was identified in both cases. Comparative genomic hybridization revealed terminal gains on chromosomes 1q and Xq and terminal loss on 1p in the hepatoblastoma, and gains in 1p, 12q, 16p, 20q, 22q, and whole chromosome 19 and loss of Xq in the renal-cell carcinoma. Our results confirm a common genetic basis for cardiac malformations, and del22q11.2 presents a risk factor for the development of pediatric tumours.