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As SARS-CoV-2 continues to spread and evolve, detecting emerging variants early is critical for public health interventions. Inferring lineage prevalence by clinical testing is infeasible at scale, especially in areas with limited resources, participation, or testing and/or sequencing capacity, which can also introduce biases1-3. SARS-CoV-2 RNA concentration in wastewater successfully tracks regional infection dynamics and provides less biased abundance estimates than clinical testing4,5. Tracking virus genomic sequences in wastewater would improve community prevalence estimates and detect emerging variants. However, two factors limit wastewater-based genomic surveillance: low-quality sequence data and inability to estimate relative lineage abundance in mixed samples. Here we resolve these critical issues to perform a high-resolution, 295-day wastewater and clinical sequencing effort, in the controlled environment of a large university campus and the broader context of the surrounding county. We developed and deployed improved virus concentration protocols and deconvolution software that fully resolve multiple virus strains from wastewater. We detected emerging variants of concern up to 14 days earlier in wastewater samples, and identified multiple instances of virus spread not captured by clinical genomic surveillance. Our study provides a scalable solution for wastewater genomic surveillance that allows early detection of SARS-CoV-2 variants and identification of cryptic transmission.
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COVID-19 , SARS-CoV-2 , Vigilância Epidemiológica Baseada em Águas Residuárias , Águas Residuárias , COVID-19/epidemiologia , COVID-19/transmissão , COVID-19/virologia , Humanos , RNA Viral/análise , RNA Viral/genética , SARS-CoV-2/classificação , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Análise de Sequência de RNA , Águas Residuárias/virologiaRESUMO
Although next-generation sequencing has enabled diagnoses for many patients with Mendelian disorders, the majority remain undiagnosed. Here, we present a sibling pair who were clinically diagnosed with Escobar syndrome, however targeted gene testing was negative. Exome sequencing (ES), and later genome sequencing (GS), revealed compound heterozygous TTN variants in both siblings, a maternally inherited frameshift variant [(NM_133378.4):c.36812del; p.(Asp12271Valfs*10)], and a paternally inherited missense variant [(NM_133378.4):c.12322G > A; p.(Asp4108Asn)]. This result was considered nondiagnostic due to poor clinical fit and limited pathogenicity evidence for the missense variant of uncertain significance (VUS). Following initial nondiagnostic RNA sequencing (RNAseq) on muscle and further pursuit of other variants detected on the ES/GS, a reanalysis of noncanonical splice sites in the muscle transcriptome identified an out-of-frame exon retraction in TTN, near the known VUS. Interim literature included reports of patients with similar TTN variants who had phenotypic concordance with the siblings, and a diagnosis of a congenital titinopathy was given 4 years after the TTN variants had been initially reported. This report highlights the value of reanalysis of RNAseq with a different approach, expands the phenotypic spectrum of congenital titinopathy and also illustrates how a perceived phenotypic mismatch, and failure to consider known variants, can result in a prolongation of the diagnostic journey.
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Post-zygotically acquired genetic variants, or somatic variants, that arise during cortical development have emerged as important causes of focal epilepsies, particularly those due to malformations of cortical development. Pathogenic somatic variants have been identified in many genes within the PI3K-AKT-mTOR-signalling pathway in individuals with hemimegalencephaly and focal cortical dysplasia (type II), and more recently in SLC35A2 in individuals with focal cortical dysplasia (type I) or non-dysplastic epileptic cortex. Given the expanding role of somatic variants across different brain malformations, we sought to delineate the landscape of somatic variants in a large cohort of patients who underwent epilepsy surgery with hemimegalencephaly or focal cortical dysplasia. We evaluated samples from 123 children with hemimegalencephaly (n = 16), focal cortical dysplasia type I and related phenotypes (n = 48), focal cortical dysplasia type II (n = 44), or focal cortical dysplasia type III (n = 15). We performed high-depth exome sequencing in brain tissue-derived DNA from each case and identified somatic single nucleotide, indel and large copy number variants. In 75% of individuals with hemimegalencephaly and 29% with focal cortical dysplasia type II, we identified pathogenic variants in PI3K-AKT-mTOR pathway genes. Four of 48 cases with focal cortical dysplasia type I (8%) had a likely pathogenic variant in SLC35A2. While no other gene had multiple disease-causing somatic variants across the focal cortical dysplasia type I cohort, four individuals in this group had a single pathogenic or likely pathogenic somatic variant in CASK, KRAS, NF1 and NIPBL, genes previously associated with neurodevelopmental disorders. No rare pathogenic or likely pathogenic somatic variants in any neurological disease genes like those identified in the focal cortical dysplasia type I cohort were found in 63 neurologically normal controls (P = 0.017), suggesting a role for these novel variants. We also identified a somatic loss-of-function variant in the known epilepsy gene, PCDH19, present in a small number of alleles in the dysplastic tissue from a female patient with focal cortical dysplasia IIIa with hippocampal sclerosis. In contrast to focal cortical dysplasia type II, neither focal cortical dysplasia type I nor III had somatic variants in genes that converge on a unifying biological pathway, suggesting greater genetic heterogeneity compared to type II. Importantly, we demonstrate that focal cortical dysplasia types I, II and III are associated with somatic gene variants across a broad range of genes, many associated with epilepsy in clinical syndromes caused by germline variants, as well as including some not previously associated with radiographically evident cortical brain malformations.
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Epilepsia , Hemimegalencefalia , Malformações do Desenvolvimento Cortical , Caderinas , Proteínas de Ciclo Celular , Feminino , Humanos , Malformações do Desenvolvimento Cortical do Grupo I , Mutação , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Protocaderinas , Serina-Treonina Quinases TORRESUMO
IRGM and its mouse orthologue Irgm1 are dynamin-like proteins that regulate vesicular remodeling, intracellular microbial killing, and pathogen immunity. IRGM dysfunction is linked to inflammatory bowel disease (IBD), and while it is thought that defective intracellular killing of microbes underscores IBD susceptibility, studies have yet to address how IRGM/Irgm1 regulates immunity to microbes relevant to intestinal inflammation. Here we find that loss of Irgm1 confers marked susceptibility to Citrobacter rodentium, a noninvasive intestinal pathogen that models inflammatory responses to intestinal bacteria. Irgm1-deficient mice fail to control C. rodentium outgrowth in the intestine, leading to systemic pathogen spread and host mortality. Surprisingly, susceptibility due to loss of Irgm1 function was not linked to defective intracellular killing of C. rodentium or exaggerated inflammation, but was instead linked to failure to remodel specific colon lamina propria (C-LP) myeloid cells that expand in response to C. rodentium infection and are essential for C. rodentium immunity. Defective immune remodeling was most striking in C-LP monocytes, which were successfully recruited to the infected C-LP, but subsequently underwent apoptosis. Apoptotic susceptibility was induced by C. rodentium infection and was specific to this setting of pathogen infection, and was not apparent in other settings of intestinal inflammation. These studies reveal a novel role for Irgm1 in host defense and suggest that deficiencies in survival and remodeling of C-LP myeloid cells that control inflammatory intestinal bacteria may underpin IBD pathogenesis linked to IRGM dysfunction.
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Citrobacter rodentium/imunologia , Colo/imunologia , Infecções por Enterobacteriaceae/imunologia , Proteínas de Ligação ao GTP/deficiência , Doenças Inflamatórias Intestinais/imunologia , Monócitos/imunologia , Animais , Colo/microbiologia , Colo/patologia , Infecções por Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/patologia , Proteínas de Ligação ao GTP/imunologia , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/patologia , Camundongos , Camundongos Knockout , Monócitos/microbiologia , Monócitos/patologia , Mucosa/imunologia , Mucosa/microbiologia , Mucosa/patologiaRESUMO
INTRODUCTION: Intraoperative neuromonitoring (IONM) is commonly used during surgery of the spine and spinal cord for early surveillance of iatrogenic injury to the central and peripheral nervous system. However, for infants and young children under 3 years of age, the use of IONM is challenging due to incomplete central and peripheral myelination. CASE PRESENTATION: We report a case of a T4-T6 dermal sinus tract (DST) that was resected on day of life 23, with the successful use of IONM. CONCLUSION: To our knowledge, this is the youngest reported case of the use of IONM in the surgical correction of a DST in a neonatal patient. This case demonstrates the potential efficacy of IONM in neonatal spine surgery and the techniques used to adapt the technology to an immature nervous system.
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Fístula , Monitorização Neurofisiológica Intraoperatória , Espinha Bífida Oculta , Criança , Pré-Escolar , Potencial Evocado Motor/fisiologia , Humanos , Lactente , Recém-Nascido , Monitorização Neurofisiológica Intraoperatória/métodos , Procedimentos Neurocirúrgicos/métodos , Estudos Retrospectivos , Espinha Bífida Oculta/diagnóstico por imagem , Espinha Bífida Oculta/cirurgia , Coluna VertebralRESUMO
A number of neoplasms of the central nervous system can demonstrate diffuse eosinophilic globules, known to be secretory products of the corresponding cell type, but they have not been a salient feature in descriptions of classic ependymoma. Here, we present a case of a posterior fossa ependymoma demonstrating glassy PAS-positive, diastase-resistant, eosinophilic globules with light microscopic and ultrastructural features resembling Reissner fiber, the secretory product of the subcommissural organ. While there has been a single published description of an ependymoma with intra- and extracellular granulofibrillary material suggested to be evidence of secretory differentiation, ours is the first case to demonstrate diffuse eosinophilic globules in an ependymoma. The extent of globules allowed full study by electron microscopy to provide new insight into the secretory material and the surrounding structures. Our findings suggest that neoplastic ependymal cells can recapitulate the secretory capacity of the subcommissural organ.
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Ependimoma/ultraestrutura , Neoplasias Infratentoriais/ultraestrutura , Adolescente , Ependimoma/patologia , Humanos , Neoplasias Infratentoriais/patologia , MasculinoRESUMO
Gain-of-function mutations in TRPC6 cause familial focal segmental glomerulosclerosis, and TRPC6 is upregulated in glomerular diseases including diabetic kidney disease. We studied the effect of systemic TRPC6 knockout in the Akita model of type 1 diabetes. Knockout of TRPC6 inhibited albuminuria in Akita mice at 12 and 16 weeks of age, but this difference disappeared by 20 weeks. Knockout of TRPC6 also reduced tubular injury in Akita mice; however, mesangial expansion was significantly increased. Hyperglycemia and blood pressure were similar between TRPC6 knockout and wild-type Akita mice, but knockout mice were more insulin resistant. In cultured podocytes, knockout of TRPC6 inhibited expression of the calcium/calcineurin responsive gene insulin receptor substrate 2 and decreased insulin responsiveness. Insulin resistance is reported to promote diabetic kidney disease independent of blood glucose levels. While the mechanisms are not fully understood, insulin activates both Akt2 and ERK, which inhibits apoptosis signal regulated kinase 1 (ASK1)-p38-induced apoptosis. In cultured podocytes, hyperglycemia stimulated p38 signaling and induced apoptosis, which was reduced by insulin and ASK1 inhibition and enhanced by Akt or ERK inhibition. Glomerular p38 signaling was increased in TRPC6 knockout Akita mice and was associated with enhanced expression of the p38 gene target cyclooxygenase 2. These data suggest that knockout of TRPC6 in Akita mice promotes insulin resistance and exacerbates glomerular disease independent of hyperglycemia.
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Diabetes Mellitus Tipo 1/complicações , Nefropatias Diabéticas/patologia , Mesângio Glomerular/patologia , Canais de Cátion TRPC/metabolismo , Animais , Apoptose , Glicemia/análise , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/etiologia , Modelos Animais de Doenças , Humanos , Proteínas Substratos do Receptor de Insulina/metabolismo , Resistência à Insulina/genética , MAP Quinase Quinase Quinase 5/metabolismo , Camundongos , Camundongos Knockout , Podócitos , Canais de Cátion TRPC/genética , Canal de Cátion TRPC6RESUMO
BACKGROUND: New Zealand's Bowel Screening Pilot (BSP) used a mailed invitation to return a faecal immunochemical test. As a pilot it offered opportunities to test interventions for reducing ethnic inequities in colorectal cancer screening prior to nationwide programme introduction. Small media interventions (e.g. educational material and DVDs) have been used at both community and participant level to improve uptake. We tested whether a DVD originally produced to raise community awareness among the Maori population would have a positive impact on participation and reduce the proportion of incorrectly performed tests (spoiled kits) if mailed out with the usual reminder letter. METHODS: The study was a parallel groups pseudo-randomised controlled trial. Over 12 months, all Maori and Pacific ethnicity non-responders four weeks after being mailed the test kit were allocated on alternate weeks to be sent, or not, the DVD intervention with the usual reminder letter. The objective was to determine changes in participation and spoiled kit rates in each ethnic group, determined three months from the date the reminder letter was sent. Participants and those recording the outcomes (receipt of a spoiled or non-spoiled test kit) were blinded to group assignment. RESULTS: 2333 Maori and 2938 Pacific people participated (11 withdrew). Those who were sent the DVD (1029 Maori and 1359 Pacific) were less likely to participate in screening than those who were not (1304 Maori and 1579 Pacific). Screening participation was reduced by 12.3% (95% CI 9.1-15.5%) in Maori (13.6% versus 25.9%) and 8.3% (95% CI 5.8-10.8%) in Pacific (10.1% versus 18.4%). However, spoiled kit rates (first return) were significantly higher among those not sent the DVD (33.1% versus 12.4% in Maori and 42.1% versus 21.9% in Pacific). CONCLUSION: The DVD sent with the reminder letter to BSP non-responders reduced screening participation to an extent that more than offset the lower rate of spoiled kits. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Registry ACTRN12612001259831 . Registered 30 November 2013.
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Neoplasias Colorretais/etnologia , Promoção da Saúde/métodos , Programas de Rastreamento/estatística & dados numéricos , Havaiano Nativo ou Outro Ilhéu do Pacífico/psicologia , Gravação em Vídeo , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Havaiano Nativo ou Outro Ilhéu do Pacífico/estatística & dados numéricos , Nova Zelândia , Projetos Piloto , Avaliação de Programas e Projetos de SaúdeRESUMO
Primary central nervous system tumors are an extremely rare cause of sudden, unexpected death in children as most patients develop symptoms because of increased intracranial pressure and seek medical attention. Rarely, a forensic pathologist may encounter a primary intracranial neoplasm in a pediatric decedent that was not suspected before death. Herein, we present a case of a supratentorial neuroepithelial tumor found at autopsy in a 3-year-old African American boy without any reported significant medical history. The tumor had significant mass effect and caused cerebral edema, which ultimately resulted in transtentorial herniation and death. The gross, histopathological, immunohistochemical, and ultrastructural findings were most consistent with an anaplastic ependymoma.
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Morte Súbita/etiologia , Ependimoma/patologia , Neoplasias Supratentoriais/patologia , Pré-Escolar , Humanos , Imuno-Histoquímica , Masculino , Microscopia , Microscopia Eletrônica de TransmissãoRESUMO
PURPOSE: Acute radiologic emergencies, primarily severe contrast reactions, are rare but life-threatening events. Given a generalized paucity of formalized or mandated training, studies have shown that radiologists and trainees perform poorly when acutely managing such events. Moreover, skill base, knowledge, and comfort levels precipitously decline over time given the infrequent occurrence of these events during one's daily practice. The primary aim of this study was to assess radiologists' preparedness for managing acute radiologic emergencies and to determine the efficacy of a high-fidelity simulation based training model in an effort to provide a rationale for similar programs to be implemented on a provincial or national level. METHODS: This was a prospective, observational study of radiology residents and attending radiologists throughout the province who were recruited to attend a full-day simulation-based course presenting various cases of acute radiologic emergencies. Participant demographics were collected at the time of commencement of the workshop. Course materials were disseminated 4 weeks prior to the workshop, and a 17-question knowledge quiz was administered before and after the workshop. Likert-type questionnaires were also distributed to survey comfort levels and equipment familiarity. The knowledge quiz and questionnaire were redistributed at 3- and 6-month intervals for acquisition of follow-up data. RESULTS: A total of 14 attending radiologists and 7 residents attended the workshop, with all participants completing the preworkshop questionnaire and 90.5% (19 of 21) completing the post-workshop questionnaire. Participants' principle locations of practice were as follows: academic institutions (50%), community hospitals (36.9%), and private clinics (13.1%). A significant increase in knowledge was demonstrated, with average scores of 10 out of 17 (59%) and 14.5 out of 17 (85%) (P < .001) before and after the workshop, respectively. A significant increase in participants' comfort levels in recognizing acute anaphylactic reactions (3.5; 4.7, P < .001), commencing initial management for acute radiologic emergencies (3.3; 5.0, P < .001), and administering the correct dose for anaphylactic reactions (2.5; 4.8, P < .001) was also demonstrated. Moreover, participants became increasingly familiar with the contents and equipment found within contrast reaction kits (2.8; 3.8, P < .01). Repeat evaluations at 3 and 6 months found an average knowledge test score of 13.8 out of 17 (81%) and 10.8 out of 17 (64%), respectively. Comfort levels were also reassessed in recognizing acute anaphylactic reactions (4.5; 4.1), commencing initial management (4.0; 3.9) and administering the correct dose of medication (4.0; 3.7) at 3- and 6-month intervals. CONCLUSIONS: Acute radiologic emergencies are rare but life-threatening events that require rapid diagnosis and treatment to mitigate associated morbidity and mortality. Simulation-based workshops are a highly efficacious training model to increase knowledge, comfort levels, and equipment familiarity for radiologists and trainees alike; however, retraining at regular intervals is required.
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Anafilaxia/terapia , Competência Clínica/estatística & dados numéricos , Meios de Contraste/efeitos adversos , Internato e Residência , Simulação de Paciente , Radiologia/educação , Anafilaxia/induzido quimicamente , Anafilaxia/diagnóstico , Canadá , Avaliação Educacional , Humanos , Estudos Prospectivos , Radiologistas/normas , Radiologistas/estatística & dados numéricos , Inquéritos e QuestionáriosRESUMO
Enhanced expression of cyclooxygenase 2 (COX2) in podocytes contributes to glomerular injury in diabetic kidney disease, but some basal level of podocyte COX2 expression might be required to promote podocyte attachment and/or survival. To investigate the role of podocyte COX2 expression in diabetic kidney disease, we deleted COX2 specifically in podocytes in a mouse model of Type 1 diabetes mellitus (Akita mice). Podocyte-specific knockout (KO) of COX2 did not affect renal morphology or albuminuria in nondiabetic mice. Albuminuria was significantly increased in wild-type (WT) and KO Akita mice compared with nondiabetic controls, and the increase in albuminuria was significantly greater in KO Akita mice compared with WT Akita mice at both 16 and 20 wk of age. At the 20-wk time point, mesangial expansion was also increased in WT and KO Akita mice compared with nondiabetic animals, and these histologic abnormalities were not improved by KO of COX2. Tubular injury was seen only in diabetic mice, but there were no significant differences between groups. Thus, KO of COX2 enhanced albuminuria and did not improve the histopathologic features of diabetic kidney disease. These data suggest that 1) KO of COX2 in podocytes does not ameliorate diabetic kidney disease in Akita mice, and 2) some basal level of podocyte COX2 expression in podocytes is necessary to attenuate the adverse effects of diabetes on glomerular filtration barrier function.
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Albuminúria/enzimologia , Ciclo-Oxigenase 2/deficiência , Nefropatias Diabéticas/enzimologia , Podócitos/enzimologia , Albuminúria/genética , Albuminúria/patologia , Albuminúria/urina , Animais , Biomarcadores/sangue , Biomarcadores/urina , Glicemia/metabolismo , Pressão Sanguínea , Ciclo-Oxigenase 2/genética , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/urina , Modelos Animais de Doenças , Eicosanoides/urina , Predisposição Genética para Doença , Integrases/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Proteínas de Membrana/genética , Camundongos da Linhagem 129 , Camundongos Knockout , Fenótipo , Podócitos/ultraestrutura , Regiões Promotoras Genéticas , Renina/metabolismo , Índice de Gravidade de DoençaRESUMO
Inappropriate activation of the renin angiotensin system (RAS) is a key contributor to the pathogenesis of essential hypertension. During RAS activation, infiltration of immune cells into the kidney exacerbates hypertension and renal injury. However, the mechanisms underpinning the accumulation of mononuclear cells in the kidney after RAS stimulation remain unclear. C-C motif chemokine 5 (CCL5) drives recruitment of macrophages and T lymphocytes into injured tissues, and we have found that RAS activation induces CCL5 expression in the kidney during the pathogenesis of hypertension and renal fibrosis. We therefore evaluated the contribution of CCL5 to renal damage and fibrosis in hypertensive and normotensive models of RAS stimulation. Surprisingly, during angiotensin II-induced hypertension, CCL5-deficient (knockout, KO) mice exhibited markedly augmented kidney damage, macrophage infiltration, and expression of proinflammatory macrophage cytokines compared with wild-type controls. When subjected to the normotensive unilateral ureteral obstruction model of endogenous RAS activation, CCL5 KO mice similarly developed more severe renal fibrosis and greater accumulation of macrophages in the kidney, congruent with enhanced renal expression of the macrophage chemokine CCL2. In turn, pharmacologic inhibition of CCL2 abrogated the differences between CCL5 KO and wild-type mice in kidney fibrosis and macrophage infiltration after unilateral ureteral obstruction. These data indicate that CCL5 paradoxically limits macrophage accumulation in the injured kidney during RAS activation by constraining the proinflammatory actions of CCL2.
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Angiotensina II/imunologia , Quimiocina CCL5/metabolismo , Hipertensão/imunologia , Nefropatias/imunologia , Rim/patologia , Animais , Pressão Sanguínea , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Quimiocina CCL5/genética , Hipertensão Essencial , Feminino , Fibrose , Hipertensão/etiologia , Rim/imunologia , Rim/cirurgia , Nefropatias/etiologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Knockout , Nefrectomia , Sistema Renina-Angiotensina/imunologia , Linfócitos T/imunologia , Obstrução UreteralRESUMO
PRKAG2 encodes the γ2 subunit of AMP-activated protein kinase (AMPK), which is an important regulator of cardiac metabolism. Mutations in PRKAG2 cause a cardiac syndrome comprising ventricular hypertrophy, pre-excitation, and progressive conduction-system disease, which is typically not diagnosed until adolescence or young adulthood. However, significant variability exists in the presentation and outcomes of patients with PRKAG2 mutations, with presentation in infancy being underrecognized. The diagnosis of PRKAG2 can be challenging in infants, and we describe our experience with three patients who were initially suspected to have Pompe disease yet ultimately diagnosed with mutations in PRKAG2. A disease-causing PRKAG2 mutation was identified in each case, with a novel missense mutation described in one patient. We highlight the potential for patients with PRKAG2 mutations to mimic Pompe disease in infancy and the need for confirmatory testing when diagnosing Pompe disease.
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Proteínas Quinases Ativadas por AMP/genética , Mutação/genética , Pré-Escolar , Feminino , Doença de Depósito de Glicogênio Tipo II/genética , Humanos , Lactente , Recém-Nascido , MasculinoRESUMO
Multivariate biomarkers are needed for detecting Alzheimer's disease (AD), understanding its etiology, and quantifying the effect of therapies. Mouse models provide opportunities to study characteristics of AD in well-controlled environments that can help facilitate development of early interventions. The CVN-AD mouse model replicates multiple AD hallmark pathologies, and we identified multivariate biomarkers characterizing a brain circuit disruption predictive of cognitive decline. In vivo and ex vivo magnetic resonance imaging (MRI) revealed that CVN-AD mice replicate the hippocampal atrophy (6%), characteristic of humans with AD, and also present changes in subcortical areas. The largest effect was in the fornix (23% smaller), which connects the septum, hippocampus, and hypothalamus. In characterizing the fornix with diffusion tensor imaging, fractional anisotropy was most sensitive (20% reduction), followed by radial (15%) and axial diffusivity (2%), in detecting pathological changes. These findings were strengthened by optical microscopy and ultrastructural analyses. Ultrastructual analysis provided estimates of axonal density, diameters, and myelination-through the g-ratio, defined as the ratio between the axonal diameter, and the diameter of the axon plus the myelin sheath. The fornix had reduced axonal density (47% fewer), axonal degeneration (13% larger axons), and abnormal myelination (1.5% smaller g-ratios). CD68 staining showed that white matter pathology could be secondary to neuronal degeneration, or due to direct microglial attack. In conclusion, these findings strengthen the hypothesis that the fornix plays a role in AD, and can be used as a disease biomarker and as a target for therapy.
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Doença de Alzheimer/patologia , Imagem de Tensor de Difusão/métodos , Fórnice/patologia , Hipocampo/patologia , Microscopia Eletrônica/métodos , Substância Branca/patologia , Doença de Alzheimer/diagnóstico por imagem , Animais , Atrofia/patologia , Biomarcadores , Modelos Animais de Doenças , Fórnice/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Camundongos , Camundongos Transgênicos , Substância Branca/diagnóstico por imagemRESUMO
Effective dosages for enzyme replacement therapy (ERT) in Pompe disease are much higher than for other lysosomal storage disorders, which has been attributed to low cation-independent mannose-6-phosphate receptor (CI-MPR) in skeletal muscle. We have previously demonstrated the benefit of increased CI-MPR-mediated uptake of recombinant human acid-α-glucosidase during ERT in mice with Pompe disease following addition of albuterol therapy. Currently we have completed a pilot study of albuterol in patients with late-onset Pompe disease already on ERT for >2 yr, who were not improving further. The 6-min walk test (6MWT) distance increased in all 7 subjects at wk 6 (30±13 m; P=0.002), wk 12 (34±14 m; P=0.004), and wk 24 (42±37 m; P=0.02), in comparison with baseline. Grip strength was improved significantly for both hands at wk 12. Furthermore, individual subjects reported benefits; e.g., a female patient could stand up from sitting on the floor much more easily (time for supine to standing position decreased from 30 to 11 s), and a male patient could readily swing his legs out of his van seat (hip abduction increased from 1 to 2+ on manual muscle testing). Finally, analysis of the quadriceps biopsies suggested increased CI-MPR at wk 12 (P=0.08), compared with baseline. With the exception of 1 patient who succumbed to respiratory complications of Pompe disease in the first week, only mild adverse events have been reported, including tremor, transient difficulty falling asleep, and mild urinary retention (requiring early morning voiding). Therefore, this pilot study revealed initial safety and efficacy in an open label study of adjunctive albuterol therapy in patients with late-onset Pompe disease who had been stable on ERT with no improvements noted over the previous several years.
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Agonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Albuterol/uso terapêutico , Terapia de Reposição de Enzimas/métodos , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Biópsia , Eletrocardiografia , Feminino , Força da Mão , Humanos , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Projetos Piloto , Músculo Quadríceps/metabolismo , Receptor IGF Tipo 2/metabolismo , Fatores de Tempo , Resultado do Tratamento , CaminhadaRESUMO
Rhabdomyomatous mesenchymal hamartoma (RMH) is a rare congenital malformation involving the dermis and subcutaneous tissue, of which there were 62 reported cases through 2014. We report RMH in two neonates presenting as a sacral skin tag. In both cases, magnetic resonance imaging (MRI) of the spine showed evidence of spinal dysraphism, including a lipomyelomeningocele and a tethered cord. Surgical repair of the defects was performed. Histopathologic examination of the skin tags showed a haphazard arrangement of mature skeletal muscle fibers and adnexal elements, consistent with RMH. The second patient also had a hemangioma on the sacrum and was diagnosed with LUMBAR (lower body hemangioma and other cutaneous defects, urogenital anomalies/ulceration, myelopathy, bony deformities, anorectal/arterial anomalies, and renal anomalies) syndrome, an association between cutaneous infantile hemangiomas of the lower body and regional congenital anomalies. The apparent association of paraspinal RMH with spinal dysraphism suggests that aberrant migration of mesodermally derived tissues (including skeletal muscle fibers) during neural tube development may be responsible for the pathologic findings in the skin. Additional study of patients with spinal dysraphism and congenital cutaneous lesions may further support this hypothesis.
Assuntos
Hamartoma/diagnóstico , Mesoderma/patologia , Rabdomioma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Disrafismo Espinal/diagnóstico , Diagnóstico Diferencial , Feminino , Seguimentos , Hamartoma/patologia , Hamartoma/cirurgia , Hemangioma/diagnóstico , Hemangioma/patologia , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética/métodos , Rabdomioma/patologia , Neoplasias Cutâneas/patologia , Disrafismo Espinal/patologia , Disrafismo Espinal/cirurgiaRESUMO
To determine if augmenting podocyte injury promotes the development of advanced diabetic nephropathy (DN), we created mice that expressed the enzyme cytosine deaminase (CD) specifically in podocytes of diabetic Akita mice (Akita-CD mice). In these mice, treatment with the prodrug 5-flucytosine (5-FC) causes podocyte injury as a result of conversion to the toxic metabolite 5-fluorouracil (5-FU). We found that treatment of 4-5 week old Akita mice with 5-FC for 5 days caused robust albuminuria at 16 and 20 weeks of age compared to 5-FC treated Akita controls, which do not express CD (Akita CTLs). By 20 weeks of age, there was a significant increase in mesangial expansion in Akita-CD mice compared to Akita CTLs, which was associated with a variable increase in glomerular basement membrane (GBM) width and interstitial fibrosis. At 20 weeks of age, podocyte number was similarly reduced in both groups of Akita mice, and was inversely correlated with the albuminuria and mesangial expansion. Thus, enhancing podocyte injury early in the disease process promotes the development of prominent mesangial expansion, interstitial fibrosis, increased GBM thickness and robust albuminuria. These data suggest that podocytes play a key role in the development of advanced features of diabetic kidney disease.
Assuntos
Nefropatias Diabéticas/patologia , Rim/patologia , Podócitos/patologia , Albuminúria/complicações , Animais , Antimetabólitos/efeitos adversos , Citosina Desaminase/genética , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/enzimologia , Nefropatias Diabéticas/genética , Modelos Animais de Doenças , Flucitosina/efeitos adversos , Fluoruracila/efeitos adversos , Expressão Gênica , Rim/efeitos dos fármacos , Rim/enzimologia , Rim/metabolismo , Camundongos , Podócitos/efeitos dos fármacos , Podócitos/enzimologia , Podócitos/metabolismo , Pró-Fármacos/efeitos adversosRESUMO
Urethral mesh placement has become a common surgical intervention for the management of stress urinary incontinence. While this procedure offers significant benefits, it is not without potential complications. This review article aims to provide a comprehensive overview of urethral mesh assessment in oncologic patients. The article explores normal magnetic resonance imaging (MRI) and computed tomography (CT) mesh appearances and highlights the pathological aspects associated with urethral mesh complications including both short-term and long-term post-operative complications. By understanding the spectrum of normal findings of urethral mesh and the possible complications, clinicians can improve patient outcomes and make informed decisions regarding urethral mesh management in this patient population.