136 research outputs found
Optimal Trading Execution with Nonlinear Market Impact: An Alternative Solution Method
We consider the optimal trade execution strategies for a large portfolio of single stocks proposed by Almgren (2003). This framework accounts for a nonlinear impact of trades on average market prices. The execution strategy of Almgren (2003) is based on the assumption that no shares per unit of time are trade at the beginning of the period. We use a general solution method that accomodates the case of positive initial trades. Our results are twofold. First of all, we show that the problem admits a solution with no trading in the opening period only if additional parametric restrictions are imposed. Second, with positive initial trading, the optimal execution time depends on trading activity in the initial period.
Looking back and beyond the 2017 diagnostic criteria for hypermobile Ehlers-Danlos syndrome: A retrospective cross-sectional study from an Italian reference center
The most common conditions with symptomatic joint hypermobility are hypermobile Ehlers-Danlos syndrome (hEDS) and hypermobility spectrum disorders (HSD). Diagnosing these overlapping connective tissue disorders remains challenging due to the lack of established causes and reliable diagnostic tests. hEDS is diagnosed applying the 2017 diagnostic criteria, and patients with symptomatic joint hypermobility but not fulfilling these criteria are labeled as HSD, which is not officially recognized by all healthcare systems. The 2017 criteria were introduced to improve diagnostic specificity but have faced criticism for being too stringent and failing to adequately capture the multisystemic involvement of hEDS. Herein, we retrospectively evaluated 327 patients from 213 families with a prior diagnosis of hypermobility type EDS or joint hypermobility syndrome based on Villefranche and Brighton criteria, to assess the effectiveness of the 2017 criteria in distinguishing between hEDS and HSD and document the frequencies of extra-articular manifestations. Based on our findings, we propose that the 2017 criteria should be made less stringent to include a greater number of patients who are currently encompassed within the HSD category. This will lead to improved diagnostic accuracy and enhanced patient care by properly capturing the diverse range of symptoms and manifestations present within the hEDS/HSD spectrum
Opis svojstava ekstra djevičanskog maslinovog ulja dobivenog iz raznih kultivara
The determination of some minor components of extra virgin olive oil, and in particular of the polyphenolic fraction of pigments and fragrances, can contribute to the characterization of the monovarietal productions: the quali-quantitative assessment of these substances can in fact contribute to the valorisation of typicalities and, at the same time, consent to the optimisation of the operational techniques during the processing and the eventual blending.
The analytical techniques, applied here for the characterisation of extra virgin olive oil of Abruzzo and Istria, have highlighted that chemical composition can enhance the valorisation of these typical products. Nevertheless, further sampling program is needed to evidence typical composition profile that might be used as “origin markers”.Određivarije nekih manjih komponenata ekstra djevičanskog maslinovog ulja, naročito polifenolne frakcije pigmemta i mirisa, može doprinijeti svojstvima monovarijetetnih proizvoda: kvalitativna i kvalitativna procjena tih supstancija može zapravo doprinijeti valorizaciji tipičnosti te, istodobno omogućiti optimizaciju operativnih tehnika za vrijeme prerade i miješanja.
Analitičke tehnike, ovdje primijenjene za opis svojstava ekstra djevičanskog maslinovog ulja iz Abruzza i Istre pokazuju da kemijski sastav može popraviti vrijednost ovih tipičnih proizvoda. Ipak, potreban je dodatni program uzorkovanja da se dokaže tipični profil sas¬tava, što se može upotrijebiti kao "oznaka podrijetla"
Deciphering disease signatures and molecular targets in vascular Ehlers-Danlos syndrome through transcriptome and miRNome sequencing of dermal fibroblasts
Vascular Ehlers-Danlos syndrome (vEDS) is a severe connective tissue disorder caused by dominant mutations in the COL3A1 gene encoding type III collagen (COLLIII). COLLIII is primarily found in blood vessels and hollow organs, and its deficiency leads to soft connective tissues fragility, resulting in life-threatening arterial and organ ruptures. There are no current targeted therapies available. Although the disease usually results from COLLIII misfolding due to triple helix structure disruption, the underlying pathomechanisms are largely unknown. To address this knowledge gap, we performed a comprehensive transcriptome analysis using RNA- and miRNA-seq on a large cohort of dermal fibroblasts from vEDS patients and healthy donors. Our investigation revealed an intricate interplay between proteostasis abnormalities, inefficient endoplasmic reticulum stress response, and compromised autophagy, which may significantly impact the molecular pathology. We also present the first detailed miRNAs expression profile in patient cells, demonstrating that several aberrantly expressed miRNAs can disrupt critical cellular functions involved in vEDS pathophysiology, such as autophagy, proteostasis, and mTOR signaling. Target prediction and regulatory networks analyses suggested potential interactions among miRNAs, lncRNAs, and candidate target genes linked to extracellular matrix organization and autophagy-lysosome pathway. Our results highlight the importance of understanding the functional role of ncRNAs in vEDS pathogenesis, shedding light on possible miRNAs and lncRNAs signatures and their functional implications for dysregulated pathways related to disease. Deciphering this complex molecular network of RNA interactions may yield additional evidence for potential disease biomolecules and targets, assisting in the design of effective patient treatment strategies
Generation of the induced pluripotent stem cell line UNIBSi017-A from an individual with cardiospondylocarpofacial syndrome and the MAP3K7 c.737-7A > G variant.
Recurrent exercise-induced acute renal failure in a young Pakistani man with severe renal hypouricemia and SLC2A9 compound heterozygosity.
BACKGROUND:
Familial renal hypouricemia (RHUC) is a hereditary disease characterized by hypouricemia, high renal fractional excretion of uric acid (FE-UA) and can be complicated by acute kidney failure and nephrolithiasis. Loss-of-function mutations in the SLC22A12 gene cause renal hypouricemia type 1 (RHUC1), whereas renal hypouricemia type 2 (RHUC2) is caused by mutations in the SLC2A9 gene.
CASE PRESENTATION:
We describe a 24-year-old Pakistani man who was admitted twice to our hospital for severe exercise-induced acute renal failure (EIARF), abdominal pain and fever; he had very low serum UA levels (0.2 mg/dl the first time and 0.09 mg/dl the second time) and high FE-UA (200% and 732% respectively), suggestive of RHUC. Mutational analyses of both urate transporters revealed a new compound heterozygosity for two distinct missense mutations in the SLC2A9 gene: p.Arg380Trp, already identified in heterozygosity, and p.Gly216Arg, previously found in homozygosity or compound heterozygosity in some RHUC2 patients. Compared with previously reported patients harbouring these mutations, our proband showed the highest FE-UA levels, suggesting that the combination of p.Arg380Trp and p.Gly216Arg mutations most severely affects the renal handling of UA.
CONCLUSIONS:
The clinical and molecular findings from this patient and a review of the literature provide new insights into the genotype-phenotype correlation of this disorder, supporting the evidence of an autosomal recessive inheritance pattern for RHUC2. Further investigations into the functional properties of GLUT9, URAT1 and other urate transporters are required to assess their potential research and clinical implications
Clinical and molecular characterization of 40 patients with classic Ehlers--Danlos syndrome: identification of 18 COL5A1 and 2 COL5A2 novel mutations.
Classic Ehlers-Danlos syndrome (cEDS) is a rare autosomal dominant connective tissue disorder that is primarily characterized by skin hyperextensibility, abnormal wound healing/atrophic scars, and joint hypermobility. A recent study demonstrated that more than 90% of patients who satisfy all of these major criteria harbor a type V collagen (COLLV) defect.
This cohort included 40 patients with cEDS who were clinically diagnosed according to the Villefranche nosology. The flowchart that was adopted for mutation detection consisted of sequencing the COL5A1 gene and, if no mutation was detected, COL5A2 analysis. In the negative patients the presence of large genomic rearrangements in COL5A1 was investigated using MLPA, and positive results were confirmed via SNP-array analysis.
We report the clinical and molecular characterization of 40 patients from 28 families, consisting of 14 pediatric patients and 26 adults. A family history of cEDS was present in 9 patients. The majority of the patients fulfilled all the major diagnostic criteria for cEDS; atrophic scars were absent in 2 females, skin hyperextensibility was not detected in a male and joint hypermobility was negative in 8 patients (20% of the entire cohort). Wide inter- and intra-familial phenotypic heterogeneity was observed. We identified causal mutations with a detection rate of approximately 93%. In 25/28 probands, COL5A1 or COL5A2 mutations were detected. Twenty-one mutations were in the COL5A1 gene, 18 of which were novel (2 recurrent). Of these, 16 mutations led to nonsense-mediated mRNA decay (NMD) and to COLLV haploinsufficiency and 5 mutations were structural. Two novel COL5A2 splice mutations were detected in patients with the most severe phenotypes. The known p. (Arg312Cys) mutation in the COL1A1 gene was identified in one patient with vascular-like cEDS.
Our findings highlight that the three major criteria for cEDS are useful and sufficient for cEDS clinical diagnosis in the large majority of the patients. The borderline patients for whom these criteria fail can be diagnosed when minor signs of connective tissue diseases and family history are present and when genetic testing reveals a defect in COLLV. Our data also confirm that COL5A1 and COL5A2 are the major, if not the only, genes involved in cEDS
Connective tissue anomalies in patients with spontaneous cervical artery dissection.
OBJECTIVE: To investigate the prevalence of connective tissue abnormalities in patients with spontaneous cervical artery dissections (sCeAD). METHODS: We systematically assessed clinically detectable signs of connective tissue aberration in a series of consecutive patients with sCeAD and of age- and sex-matched patients with ischemic stroke unrelated to CeAD (non-CeAD IS) by a standard examination protocol including 68 items, and performed extensive molecular investigation for hereditary connective tissue disorders in all patients with sCeAD. RESULTS: The study group included 84 patients with sCeAD (mean age, 44.5 ± 7.8 years; 66.7% men) and 84 patients with non-CeAD IS. None of the patients with sCeAD met clinical or molecular diagnostic criteria for established hereditary connective tissue disorder. Connective tissue abnormalities were detected more frequently in the group of patients with sCeAD than in the group of those with non-CeAD IS (mean number of pathologic findings, 4.5 ± 3.5 vs 1.9 ± 2.3; p < 0.001). Eighty-one patients (96.4%) in the sCeAD group had at least one detectable sign compared with 55 patients (66.7%) in the group with non-CeAD IS (p < 0.001). Skeletal, ocular, and skin abnormalities, as well as craniofacial dysmorphisms, were the clinical signs more strongly associated with sCeAD. Signs suggesting connective tissue abnormality were also more frequently represented in patients with sCeAD than in patients with traumatic CeAD (28.6%, p < 0.001; mean number of pathologic findings, 1.7 ± 3.7, p = 0.045). CONCLUSIONS: Connective tissue abnormalities are frequent in patients with sCeAD. This reinforces the hypothesis that systemic aberrations of the connective tissue might be implicated in the pathogenesis of the disease
Arterial Tortuosity Syndrome: a vitamin C compartmentation disease?
Arterial tortuosity syndrome (ATS, MIM #208050) is a rare autosomal recessive connective tissue disorder characterized by tortuosity and elongation of the large and medium-sized arteries and a propensity towards aneurysm formation and vascular dissection. ATS is caused by mutations in SLC2A10 encoding the facilitative glucose transporter 10 (GLUT10), whose role in the ATS pathogenesis remains still controversial. We recently showed that GLUT10 deficiency causes the dysregulation of several genes/proteins involved in TGFβ signaling, extracellular matrix architecture and pathways that control oxidative stress response. GLUT10 should be located intracellularly; however, neither the exact localization, i.e., nuclear membrane, mitochondria, or endoplasmic reticulum (ER), nor the transported substances, i.e., glucose or dehydroascorbic acid (DAA), have been demonstrated.
Here, we demonstrate that GLUT10 facilitates DAA uptake into the endomembranes and, in particular, into ER. GLUT10 produced by in vitro translation and incorporated into proteoliposomes efficiently transports DAA. Silencing of GLUT10 in hTERT immortalized human fibroblasts compromised DAA transport activity through the endomembranes. Similarly, in plasma membrane-permeabilized ATS fibroblasts a huge decrease in DAA transport was observed and the stable re-expression of GLUT10 restored the impaired DAA transport activity. Immunocytochemistry of human control fibroblasts showed a perinuclear abundance of GLUT10. Immunoblotting of subcellular fractions from human control fibroblasts revealed that GLUT10 was principally present in the microsomal fraction, containing ER-derived vesicles, as showed by the presence of the specific ER marker proteins GRP78 and GRP94, and by the almost complete absence of mitochondrial and cytoplasmic markers, VDAC1, cyclophilin D, and GAPDH, respectively. Transient expression of V5-tagged GLUT10 in ATS patients’ fibroblasts and co-localization experiments with the specific ER marker PDI definitely confirmed the ER localization of GLUT10.
Overall, the present findings demonstrate that GLUT10 facilitates DAA uptake into the ER lumen and likely to the nucleoplasm through the nuclear envelope, which is a subdomain of the ER. Our findings support both “antioxidant-” and “enzyme cofactor-” models of a vitamin C-related pathology. Indeed, AA acts as an antioxidant/electron acceptor protecting against oxidative stress-induced cellular damage by scavenging free radicals also during the process of oxidative protein folding. Furthermore, AA is an essential cofactor for α-ketoglutarate-dependent dioxygenases, such as prolyl and lysyl hydroxylases inside the ER and for ten-eleven translocation demethylases and the Jumonji protein family present in the nucleus. Thus, shortage of AA in the lumenal compartments of the secretory pathway and in the nucleoplasm can depress the production of extracellular matrix proteins at both post-translational and epigenetic levels
- …