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71.

Objective

To examine the efficacy and safety of the therapeutic regimen using oral and intravenous l-arginine for pediatric and adult patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS).

Methods

In the presence and absence of an ictus of stroke-like episodes within 6 h prior to efficacy assessment, we correspondingly conducted the systematic administration of oral and intravenous l-arginine to 15 and 10 patients with MELAS in two, 2-year, prospective, multicenter clinical trials at 10 medical institutions in Japan. Subsequently, patients were followed up for 7 years. The primary endpoint in the clinical trial of oral l-arginine was the MELAS scale, while that for intravenous l-arginine was the improvement rates of headache and nausea/vomiting at 2 h after completion of the initial intravenous administration. The relationships between the ictuses of stroke-like episodes and plasma arginine concentrations were examined.

Results

Oral l-arginine extended the interictal phase (p?=?0.0625) and decreased the incidence and severity of ictuses. Intravenous l-arginine improved the rates of four major symptoms—headache, nausea/vomiting, impaired consciousness, and visual disturbance. The maximal plasma arginine concentration was 167 μmol/L when an ictus developed. Neither death nor bedriddenness occurred during the 2-year clinical trials, and the latter did not develop during the 7-year follow-up despite the progressively neurodegenerative and eventually life-threatening nature of MELAS. No treatment-related adverse events occurred, and the formulations of l-arginine were well tolerated.

Conclusions

The systematic administration of oral and intravenous l-arginine may be therapeutically beneficial and clinically useful for patients with MELAS.
  相似文献   
72.
Severe early onset epilepsies are often caused by de novo pathogenic variants. Few studies have reported the frequency of somatic mosaicism in parents of children with severe epileptic encephalopathies. Here we aim to investigate the frequency of mosaicism in the parents of children with epilepsy caused by alleged de novo variants. We tested parental genomic DNA derived from different tissues for 75 cases using targeted next‐generation sequencing. Five parents (6.6%) showed mosaicism at minor allele frequencies of 0.8%‐29% for the pathogenic variant detected in their offspring. Parental mosaicism was observed in the following genes: SCN1A, SCN2A, SCN8A, and STXBP1. One of the identified parents had epilepsy himself. Our results show that de novo events can occur already in parental tissue and in some cases can be detected in peripheral blood. Consequently, parents affected by low‐grade mosaicism are faced with an increased recurrence risk for transmitting the pathogenic variant, compared to the overall recurrence risk for a second affected child estimated at approximately 1%. However, testing for parental somatic mosaicism will help identifying those parents who truly are at higher risk and will significantly improve genetic counseling in the respective families.  相似文献   
73.
74.

Aims/hypothesis

Not all people with type 2 diabetes who undergo bariatric surgery achieve diabetes remission. Thus it is critical to develop methods for predicting outcomes that are applicable for clinical practice. The DiaRem score is relevant for predicting diabetes remission post-Roux-en-Y gastric bypass (RYGB), but it is not accurate for all individuals across the entire spectrum of scores. We aimed to develop an improved scoring system for predicting diabetes remission following RYGB (the Advanced-DiaRem [Ad-DiaRem]).

Methods

We used a retrospective French cohort (n = 1866) that included 352 individuals with type 2 diabetes followed for 1 year post-RYGB. We developed the Ad-DiaRem in a test cohort (n = 213) and examined its accuracy in independent cohorts from France (n = 134) and Israel (n = 99).

Results

Adding two clinical variables (diabetes duration and number of glucose-lowering agents) to the original DiaRem and modifying the penalties for each category led to improved predictive performance for Ad-DiaRem. Ad-DiaRem displayed improved area under the receiver operating characteristic curve and predictive accuracy compared with DiaRem (0.911 vs 0.856 and 0.841 vs 0.789, respectively; p = 0.03); thus correcting classification for 8% of those initially misclassified with DiaRem. With Ad-DiaRem, there were also fewer misclassifications of individuals with mid-range scores. This improved predictive performance was confirmed in independent cohorts.

Conclusions/interpretation

We propose the Ad-DiaRem, which includes two additional clinical variables, as an optimised tool with improved accuracy to predict diabetes remission 1 year post-RYGB. This tool might be helpful for personalised management of individuals with diabetes when considering bariatric surgery in routine care, ultimately contributing to precision medicine.
  相似文献   
75.
Cutaneous T cell lymphomas (CTCLs) represent a heterogeneous group of non-Hodgkin lymphomas that affect the skin. The pathogenesis of these conditions is poorly understood. For example, the signaling mechanisms contributing to the dysregulated growth of the neoplastic T cells are not well defined. Here, we demonstrate that loss of nuclear localization of pro-IL-16 facilitates CTCL cell proliferation by causing a decrease in expression of the cyclin dependent-kinase inhibitor p27Kip1. The decrease in p27Kip1 expression was directly attributable to an increase in expression of S-phase kinase-associated protein 2 (Skp2). Regulation of Skp2 is in part attributed to the nuclear presence of the scaffold protein pro-IL-16. T cells isolated from 11 patients with advanced CTCL, but not those from healthy controls or patients with T cell acute lymphocytic leukemia (T-ALL), demonstrated reduction in nuclear pro-IL-16 levels. Sequence analysis identified the presence of mutations in the 5' end of the PDZ1 region of pro-IL-16, a domain required for association of pro-IL-16 with the nuclear chaperone HSC70 (also known as HSPA8). HSC70 knockdown led to loss of nuclear translocation by pro-IL-16 and subsequent increases in Skp2 levels and decreases in p27Kip1 levels, which ultimately enhanced T cell proliferation. Thus, our data indicate that advanced CTCL cell growth is facilitated, at least in part, by mutations in the scaffold protein pro-IL-16, which directly regulates Skp2 synthesis.  相似文献   
76.
The in-vitro and in-vivo biocompatibility of two oxides (TiO and ZrO) and diamond-like carbon (D) coated stents has been assessed and compared with uncoated stainless steel (St) stents. In vitro studies demonstrated that both fibrinogen adsorption and platelet adhesion were significantly higher on D coating compared to those on oxide coatings and uncoated stainless steel. In addition TiO and ZrO coatings showed evidence of a minor inflammatory response and more complete endothelialization of the aorta than that seen around D coated and uncoated St stents. The resulting neointimal growth in the aorta with TiO, ZrO, and D coated and uncoated St stents, measured 8 weeks after stenting (the ratio of the neointima in the stented artery to the non-stented artery) was 1.03 + 0.28, 0.85 + 0.36, 1.78 + 1.26, and 1.15 + 0.56, accordingly. From the data obtained it could be concluded that the increased neointima measured around D-coated stents, may be due to both, the inferior haemocompatibility of the diamond-like carbon coating and mechanical instability of D coating observed in an in vivo environment.  相似文献   
77.
Alzheimer's disease (AD) is characterized by a loss of α4β2 and α7 nicotinic acetylcholine receptors (nAChRs) in the brain and severe memory impairments. Previously, we found that antibodies elicited against extracellular domain of α7 nAChR subunit decreased the number of α7 nAChRs in the brains of mice and impaired episodic memory. Here we show that antibodies capable to bind α7(1-208) are present in the blood of both healthy humans and AD patients. In healthy individuals, their capacity to compete with [(125)-I]-α-bungarotoxin for the binding to α7(1-208) increased with age. The level of such antibodies was significantly elevated in children with severe form of obstructive bronchitis and in mice injected with Lewis lung carcinoma cells expressing both α4β2 and α7 nAChRs. Elevated antibody levels were accompanied with decreased surface nAChRs on the blood lymphocytes of children and of mice immunized with α7(1-208). Among AD patients, the level of α7 nAChR-specific antibodies was significantly larger in people 62.5 ± 1.5 years old with moderate or severe AD stages (15.2 ± 1.3 MMSE scores) compared to those of 76 ± 1.5 years old with the mild (22.7 ± 0.1 MMSE scores) AD stage. We concluded that α7(1-208) nAChR-specific antibodies found in the human blood are formed as a result of common infections accompanied with the destruction of respiratory epithelium. Elevated blood plasma levels of α7(1-208) nAChR-specific antibodies are characteristic for the early-onset AD and, therefore, are suggested as one of the risk factors for the development of this form of the disease.  相似文献   
78.
79.
Ion-selective microelectrodes (ISMs) have been used extensively in neurophysiological studies. ISMs selective for H+ and Ca2+ are notable for their sensitivity and selectivity, but suffer from a slow response time, and susceptibility to noise because of the high electrical resistance of the respective ion exchange cocktails. These drawbacks can be overcome by using a "coaxial" or "concentric" inner micropipette to shunt the bulk of the ion exchanger resistance. This approach was used decades ago to record extracellular [Ca2+] transients in cat cortex, but has not been subsequently used. Here, we describe a method for the rapid fabrication of concentric pH- and Ca2+-selective microelectrodes useful for extracellular studies in brain slices or other work in vitro. Construction was simplified compared with previous implementations, by using commercially available, thin-walled borosilicate glass, drawing an outer barrel with a rapid taper (similar to a patch pipette), and by use of a quick and reliable silanization procedure. Using a piezoelectric stepper to effect a rapid solution change, the response time constants of the concentric pH and Ca2+-electrodes were 14.9 ± 1.3 and 5.3 ± 0.90 ms, respectively. Use of these concentric ISMs is demonstrated in rat hippocampal slices. Activity-dependent, extracellular pH, and [Ca2+] transients are shown to arise two- to threefold faster, and attain amplitudes two- to fourfold greater, when recorded by concentric versus conventional ISMs. The advantage of concentric ISMs for studies of ion transport and ion diffusion is discussed.  相似文献   
80.
Although monoallelic expression (MAE) is a frequent genomic event in normal tissues, its role in tumorigenesis remains unclear. Here we carried out single-nucleotide polymorphism arrays on DNA and RNA from a large cohort of pediatric and adult brain tumor tissues to determine the genome-wide rate of MAE, its role in specific cancer-related genes, and the clinical consequences of MAE in brain tumors. We also used targeted genotyping to examine the role of tumor-related genes in brain tumor development and specifically examined the clinical consequences of MAE at TP53 and IDH1. The genome-wide rate of tumor MAE was higher than in previously described normal tissue and increased with specific tumor grade. Oncogenes, but not tumor suppressors, exhibited significantly higher MAE in high-grade compared with low-grade tumors. This method identified nine novel genes highly associated with MAE. Within cancer-related genes, MAE was gene specific; hTERT was most significantly affected, with a higher frequency of MAE in adult and advanced tumors. Clinically, MAE at TP53 exists only in mutated tumors and increases with tumor aggressiveness. MAE toward the normal allele at IDH1 conferred worse survival even in IDH1 mutated tumors. Taken together, our findings suggest that MAE is tumor and gene specific, frequent in brain tumor subtypes, and may be associated with tumor progression/aggressiveness. Further exploration of MAE at relevant genes may contribute to better understanding of tumor development and determine survival in brain tumor patients.  相似文献   
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