Project description:Knuckle pads are rare harmless subcutaneous nodules that must be differentiated from joint disease of the proximal interphalangeal or rarely of the metacarpophalangeal joints as well as from other masses of the paraarticular tissues. We present a case of an otherwise healthy 36-year-old woman presenting with bilateral knuckle pads located at the dorsal aspect of the proximal interphalangeal joints. No predisposition to a specific musculoskeletal disorder was noted. Ultrasound revealed well-delimited subcutaneous hypoechoic masses without internal flow signals at color Doppler. Histology showed proliferation of myofibroblasts with a decrease of elastic filaments in the deep dermis. The clinical picture, the family history in addition to the histology allowed us to make the diagnosis of knuckle pads. We present the ultrasound findings of knuckle pads and discuss the differential diagnosis of a "swelling" in the dorsal region of proximal interphalangeal joints and metacarpophalangeal joints.
Project description:Numerous models explore how a wide variety of biological and social phenomena spread in social networks. However, these models implicitly assume that the spread of one phenomenon is not affected by the spread of another. Here, we develop a model of "dueling contagions", with a particular illustration of a situation where one is biological (influenza) and the other is social (flu vaccination). We apply the model to unique time series data collected during the 2009 H1N1 epidemic that includes information about vaccination, flu, and face-to-face social networks. The results show that well-connected individuals are more likely to get vaccinated, as are people who are exposed to friends who get vaccinated or are exposed to friends who get the flu. Our dueling contagion model suggests that other epidemiological models may be dramatically underestimating the R0 of contagions. It also suggests that the rate of vaccination contagion may be even more important than the biological contagion in determining the course of the disease. These results suggest that real world and online platforms that make it easier to see when friends have been vaccinated (personalized vaccination campaigns) and when they get the flu (personalized flu warnings) could have a large impact on reducing the severity of epidemics. They also suggest possible benefits from understanding the coevolution of many kinds of dueling contagions.
Project description:Introduction: Intramuscular myxomas are benign tumors that are challenging to diagnose, especially on core needle biopsies. Acquired chromosomal aberrations and pathogenic variants in codon 201 or codon 227 in GNAS complex locus gene (GNAS) have been reported in these tumors. Here we present our genetic findings in a series of 22 intramuscular myxomas. Materials and methods: The tumors were investigated for the presence of acquired chromosomal aberrations using G-banding and karyotyping. Pathogenic variants in codon 201 or codon 227 of GNAS were assessed using direct cycle Sanger sequencing and Ion AmpliSeq Cancer Hotspot Panel v2 methodologies. Results: Eleven tumors carried chromosomal abnormalities. Six tumors had numerical, four had structural, and one had both numerical and structural chromosomal aberrations. Gains of chromosomes 7 and 8 were the most common abnormalities being found in five and four tumors respectively. Pathogenic variants in GNAS were detected in 19 myxomas (86%) with both methodologies. The detected pathogenic variants were p.R201H in nine cases (seven with abnormal and two with normal karyotypes), p.R201C in five cases, all with normal karyotypes, p.R201S in three cases (two with abnormal and one with normal karyotype), p.R201G in one case with a normal karyotype, and p.Q227E in one case with a normal karyotype. Conclusion: Firstly, our data indicate a possible association between chromosomal abnormalities and GNAS pathogenic variants in intramuscular myxomas. Secondly, the presence of the rare pathogenic variants R201S, p.R201G and p.Q227E in 26% (5 out of 19) of myxomas with GNAS pathogenic variants shows that methodologies designed to detect only the common "hotspot" of p.R201C and p.R201H will give false negative results. Finally, a comparison between Ion AmpliSeq Cancer Hotspot Panel v2 and direct cycle Sanger sequencing showed that direct cycle Sanger sequencing provides a quick, reliable, and relatively cheap method to detect GNAS pathogenic variants, matching even the most cutting-edge sequencing methods.
Project description:Kearns-Sayre Syndrome (KSS) is a subtype of chronic progressive external ophthalmoplegia (CPEO). In this case, A 21-year-old man diagnosed with KSS, and presented with chronic progressive blepharoptosis (ptosis) and external ophthalmoplegia, diffuse depigmentation of the retinal pigment epithelium, and cerebellar ataxia, with a cerebrospinal fluid protein of 254 mg/dL, was reported. Genetic screening revealed a novel mutated gene in SLC25A4 in the patient as well as in his mother: NM_001151:c.170G>C in exon 2. Its imaging finding is a characteristic progressive atrophy of the right cerebellar hemisphere. In conclusion, we found a case of KSS with a novel mutated gene in SLC25A4: NM_001151:c.170G>C in exon 2 as the pathogenic mechanism, and found that KSS can be caused only when the proportion of mutations in the SLC25A4 gene reach a certain degree, and the patient with KSS showed a unique cranial imaging feature of unilateral progressive cerebellar atrophy.
Project description:A 52-year-old woman presented with dysarthria and right-sided weakness in her upper and lower extremities prompting thrombolytic therapy with mild resolution of symptoms. Further work-up revealed (the source) a left ventricular myxoma on the chordae tendinae of the posterior medial papillary muscle, confirmed with transesophageal echocardiography and pathology. Herein, we present a rare case of embolic stroke from a myxoma originating on the chordae tendinae. To the best of our knowledge, the literature on the location and presentation of this tumor as seen in our patient is sparse in contemporary findings.
Project description:ObjectiveWhen studying any specific rare disease, heterogeneity and scarcity of affected individuals has historically hindered investigators from discerning on what to focus to understand and diagnose a disease. New nongenomic methodologies must be developed that identify similarities in seemingly dissimilar conditions.Materials and methodsThis observational study analyzes 1042 patients from the Undiagnosed Diseases Network (2015-2019), a multicenter, nationwide research study using phenotypic data annotated by specialized staff using Human Phenotype Ontology terms. We used Louvain community detection to cluster patients linked by Jaccard pairwise similarity and 2 support vector classifier to assign new cases. We further validated the clusters' most representative comorbidities using a national claims database (67 million patients).ResultsPatients were divided into 2 groups: those with symptom onset before 18 years of age (n = 810) and at 18 years of age or older (n = 232) (average symptom onset age: 10 [interquartile range, 0-14] years). For 810 pediatric patients, we identified 4 statistically significant clusters. Two clusters were characterized by growth disorders, and developmental delay enriched for hypotonia presented a higher likelihood of diagnosis. Support vector classifier showed 0.89 balanced accuracy (0.83 for Human Phenotype Ontology terms only) on test data.DiscussionsTo set the framework for future discovery, we chose as our endpoint the successful grouping of patients by phenotypic similarity and provide a classification tool to assign new patients to those clusters.ConclusionThis study shows that despite the scarcity and heterogeneity of patients, we can still find commonalities that can potentially be harnessed to uncover new insights and targets for therapy.
Project description:The presence of Kayser-Fleischer ring in patients with Wilson's disease (WD) is well documented and included in diagnostic algorithms; however, data about the occurrence of the second postulated ophthalmological sign of WD, sunflower cataract (SC), are limited and even conflicting. The aim of our study was to verify the occurrence of SC in WD. From January 2010 to May 2015, 81 consecutive, newly diagnosed WD patients underwent detailed ophthalmological examinations, including slit lamp examination with special attention to lens transparency, to verify the presence of SC in WD-naive patients. SC was detected in only one (1.2 %) of the examined WD patients, did not impact visual acuity; moreover, completely disappeared following a year of treatment for WD. SC may be a very rare and reversible ophthalmological manifestation of WD that is observed seldom and only at the time of WD diagnosis. We postulate that a finding of SC in WD patients is an interesting finding that may occur in the course of WD, but it is not a pathognomonic sign of WD.
Project description:Natural product discovery from environmental genomes (metagenomics) has largely been limited to the screening of existing environmental DNA (eDNA) libraries. Here, we have coupled a chemical-biogeographic survey of chromopyrrolic acid synthase (CPAS) gene diversity with targeted eDNA library production to more efficiently access rare tryptophan dimer (TD) biosynthetic gene clusters. A combination of traditional and synthetic biology-based heterologous expression efforts using eDNA-derived gene clusters led to the production of hydroxysporine (1) and reductasporine (2), two bioactive TDs. As suggested by our phylogenetic analysis of CPAS genes, identified in our survey of crude eDNA extracts, reductasporine (2) contains an unprecedented TD core structure: a pyrrolinium indolocarbazole core that is likely key to its unusual bioactivity profile. This work demonstrates the potential for the discovery of structurally rare and biologically interesting natural products using targeted metagenomics, where environmental samples are prescreened to identify the most phylogenetically unique gene sequences and molecules associated with these genes are accessed through targeted metagenomic library construction and heterologous expression.