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71.
A high serum concentration of enterolactone, an enterolignan produced by colonic microbiota from precursors in cereals, vegetables, and fruits, is associated with reduced risk of acute coronary events. Probiotics and prebiotics modify colonic metabolism and may affect the serum enterolactone concentration. The effects of a probiotic mixture alone and with galactooligosaccharides (GOS) on serum enterolactone concentration and fecal metabolism were investigated in 18 healthy men. Participants received 3 interventions, each for 2 wk: 1) probiotics [Lactobacillus rhamnosus strains GG (LGG) and LC705, Propionibacterium freudenreichii ssp. shermanii JS, and Bifidobacterium breve Bb99, for a total amount of 2 × 10(10) CFU/d]; 2) probiotics and GOS 3.8 g/d; 3) probiotics, GOS, and rye bread (minimum 120 g/d). Serum enterolactone and fecal dry weight, enzyme activities, pH, SCFA, lactic acid bacteria, bifidobacteria, propionibacteria, and the strains LGG and LC705 were determined. The serum enterolactone concentration (nmol/L) tended to be decreased from baseline [mean (95% CI) 18.6 (10.8-26.4)] by probiotics alone [15.2 (7.8-22.7); P = 0.095], was not significantly affected by probiotics with GOS [21.5 (13.2-29.8)], and was increased by probiotics with GOS and rye bread [24.6 (15.4-33.7); P < 0.05]. Probiotics alone did not affect fecal β-glucosidase activity and bifidobacteria, but probiotics with GOS decreased β-glucosidase activity and increased bifidobacteria compared with baseline (P < 0.05) and with probiotics alone (P < 0.01). In conclusion, this probiotic mixture with or without GOS does not significantly affect serum enterolactone concentration. Because probiotics with GOS decreased fecal β-glucosidase activity but not serum enterolactone, the reduced fecal β-glucosidase, within the range of activities measured, does not seem to limit the formation of enterolactone.  相似文献   
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PURPOSE: To assess the clinical picture and molecular genetics of 14 Finnish families with dominant optic atrophy (DOA). METHODS: The clinical status of family members was based on the assessment of visual acuity, colour vision, visual fields and optic nerve appearance; 31 individuals were affected, two suspect and 21 unaffected. A total of 30 coding exons and exon- intron boundaries of the OPA1 gene were sequenced in order to detect mutations. RESULTS: Half the patients were diagnosed at the age of < or = 20 years. Ten out of 20 affected individuals followed up for > or = 6 years had a progressive disease and 10 had a stable disease. According to WHO criteria, 36% of the affected patients were visually handicapped. Eight OPA1 pathogenic mutations, all but one novel, and 18 neutral polymorphisms were detected. CONCLUSION: The most sensitive indicators of DOA were optic disc pallor and dyschromatopsia. With molecular genetic analysis, asymptomatic mutation carriers and DOA cases with a mild clinical outcome were ascertained. No mutational hotspot or Finnish major mutation in the OPA1 gene could be demonstrated as most families carried a unique mutation. No obvious genotype- phenotype correlation could be detected. Detailed clinical assessment and exclusion of non-DOA families prior to mutation screening are necessary for obtaining a high mutation detection rate.  相似文献   
73.
Refractory generalised convulsive status epilepticus : a guide to treatment   总被引:2,自引:0,他引:2  
The patient with status epilepticus has continuous or rapidly repeating seizures. Generalised convulsive status epilepticus (GCSE) is the most common form of the disorder and is a life-threatening condition that requires prompt medical management. Status epilepticus that does not respond to first-line benzodiazepines (lorazepam or diazepam) or to second-line antiepileptic drugs (phenytoin/fosphenytoin, phenobarbital or valproate) is usually considered refractory and requires more aggressive treatment.The optimal treatment of refractory GCSE has not been defined, but patients should be treated in an intensive care unit, as artificial ventilation and haemodynamic support are required. Invasive haemodynamic monitoring is often necessary and EEG monitoring is essential.The drug treatment of refractory GCSE involves general anaesthesia with continuous intravenous anaesthetics given in doses that abolish all clinical and electrographic epileptic activity, often requiring sedation to the point of burst suppression on the EEG. Barbiturate anaesthetics, pentobarbital in the US and thiopental sodium in Europe and Australia, are the most frequently used agents and are highly effective for refractory GCSE both in children and adults. Indeed, they remain the only way to stop seizure activity with certainty in severely refractory cases. Other options are midazolam for adults and children and propofol for adults only.Regardless of the drug selected, intravenous fluids and vasopressors are usually required to treat hypotension. Once seizures have been controlled for 12-24 hours, continuous intravenous therapy should be gradually tapered off if the drug being administered is midazolam or propofol. Gradual tapering is probably not necessary with pentobarbital or thiopental sodium. Continuous EEG monitoring is required during high-dose treatment and while therapy is gradually withdrawn. During withdrawal of anaesthetic therapy, intravenous phenytoin/fosphenytoin or valproate should be continued (these agents having been administered during earlier phases of GCSE) to ensure an adequate baseline of antiepileptic medication so as to prevent the recurrence of status epilepticus. If additional medication is needed, the most appropriate antiepileptic drugs are gabapentin for focal seizures and levetiracetam and topiramate for all seizure types, as these drugs can be started at high doses with a low risk of idiosyncratic reactions.Even with current best practice, mortality in patients who experience refractory GCSE is about 50% and only the minority return to their premorbid functional baseline. Therefore, new treatment options are urgently needed. The ideal new drug for refractory GCSE would be one that has the ability to stop seizures more effectively and safely than current drugs, and that has neuroprotective properties to prevent the brain damage and neurological morbidity caused by GCSE.  相似文献   
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Mutations of the tumor suppressor TP53 are present in many forms of human cancer and are associated with increased tumor cell invasion and metastasis. Several mechanisms have been identified for promoting dissemination of cancer cells with TP53 mutations, including increased targeting of integrins to the plasma membrane. Here, we demonstrate a role for the filopodia-inducing motor protein Myosin-X (Myo10) in mutant p53–driven cancer invasion. Analysis of gene expression profiles from 2 breast cancer data sets revealed that MYO10 was highly expressed in aggressive cancer subtypes. Myo10 was required for breast cancer cell invasion and dissemination in multiple cancer cell lines and murine models of cancer metastasis. Evaluation of a Myo10 mutant without the integrin-binding domain revealed that the ability of Myo10 to transport β1 integrins to the filopodia tip is required for invasion. Introduction of mutant p53 promoted Myo10 expression in cancer cells and pancreatic ductal adenocarcinoma in mice, whereas suppression of endogenous mutant p53 attenuated Myo10 levels and cell invasion. In clinical breast carcinomas, Myo10 was predominantly expressed at the invasive edges and correlated with the presence of TP53 mutations and poor prognosis. These data indicate that Myo10 upregulation in mutant p53–driven cancers is necessary for invasion and that plasma-membrane protrusions, such as filopodia, may serve as specialized metastatic engines.  相似文献   
78.
Nitric oxide (NO) as a vasoactive substance is a crucial element in the pathogenesis of sepsis. Endothelial NO synthase (eNOS) is, in turn, a key regulator of vascular NO production. The eNOS gene polymorphism at position 894 (G>T, Glu298Asp) resulting in T allele has been studied in the context of vascular diseases, but its role in sepsis has not yet been explored. We here studied the effect of eNOS Glu298Asp polymorphism on the clinical course of the disease in patients with bacteremia. The study comprised 147 patients with bacteremia caused by Staphylococcus aureus, Streptococcus pneumoniae, beta-hemolytic streptococci, or Escherichia coli. Laboratory findings and clinical data were registered on admission and during 6 consecutive days. The polymorphism of eNOS gene, G894T, was genotyped. Carriage of the T allele was associated with low MAP (P = 0.004) and high Sequential Organ Failure Assessment score (P = 0.001) in patients with E. coli bacteremia. The effect on blood pressure was most prominent in the early stage of the disease (MAP on admission = 52 mmHg in T-allele carriers vs. 91 mmHg in noncarriers; P < 0.001). However, the same was not detected in bacteremia caused by a gram-positive organism (S. aureus, S. pneumoniae, or beta-hemolytic streptococci). The Glu298Asp polymorphism had no effect on case fatality in any pathogen. Carriage of the T allele of the eNOS gene is a risk factor for hypotension in patients with E. coli bacteremia but not in bacteremia caused by a gram-positive organism.  相似文献   
79.
We describe a 4-year-old boy with an accessory right thumb, short and broad toes, cryptorchidism, micrognathia, abnormally modeled ears, and delayed speech development. The chromosome analysis of patient's peripheral blood lymphocytes by conventional GTG banding demonstrated a small deletion in the long arm of chromosome 1. Confirmation and defined localization of the deleted segment to chromosomal bands 1q25.3-q31.3 was obtained by high resolution prometaphase analysis. Molecular studies, using a set of polymorphic chromosome 1q specific microsatellite markers, localized the deletion between the markers D1S2127 and D1S1727 on the paternally inherited chromosome 1. The maximum physical distance between these markers is approximately 21 Mb. The previously described two patients with 1q25-q31 deletions both had severe clinical manifestations, just as the other 10 patients with the proposed "intermediate 1q deletion syndrome," associated with 1q25-q32 deletions. Distinct from all these patients, the clinical picture of our patient is markedly milder, i.e., without growth retardation, microcephaly, or clear mental retardation.  相似文献   
80.
Conventional next‐generation sequencing methods, used in most gene panels, cannot separate maternally and paternally derived sequence information of distant variants. In recessive diseases, two or more equally plausible causative variants with unsolved phase information prevent accurate molecular diagnosis. In reality, close relatives might be unavailable for segregation analysis. Here, we utilized whole genome linked‐read sequencing to assign variants to haplotypes in two patients with inherited retinal dystrophies. Patient 1 with macular dystrophy had variants c.3442T>C, p.(Cys1148Arg), c.4209G>T, p.(Glu1403Asp), and c.1182C>T, p.(Cys394=) in CRB1, and Patient 2 with nonsyndromic retinitis pigmentosa had c.1328T>A, p.(Val443Asp) and c.3032C>G, p.(Ser1011*) in AHI1. The relatives were not available for genotyping. Using whole genome linked‐read sequencing we phased the variants to haplotypes providing genetic background for the retinal dystrophies. In future, when the price of sequencing methods that provides long‐read data decreases and their read‐depth and accuracy increases, they are probably considered the primary or adjunctive sequencing methods in genetic testing, allowing the immediate collection of phase information and thus obviating the need for the carrier testing and segregation analysis.  相似文献   
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