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1.
Transmembrane recordings and surface electrograms were used to evaluate the influence of propafenone on the cellular electrophysiology of isolated neonatal and adult rabbit atrioventricular node (AVN) preparations. An automatic interval of 863 +/- 82 ms (mean +/- SEM, n = 14) in neonates was found to be significantly shorter than the 1510- +/- 205-ms (n = 12) automatic interval observed in adults. Propafenone in a concentration of 5 x 10(-6) M significantly increased the automatic interval of neonatal pacemakers but not that of the adult preparations. These changes in automaticity produced by propafenone were not dependent on the adrenergic receptor-blocking action of the drug. The pacemaker escape time after overdrive pacing was also shorter in the neonate than in the adult. Propafenone prolonged the escape time of the neonatal tissues but not those of the adult. AVN refractory period, A-H interval, and antegrade Wenckebach rate were comparably increased in a concentration-dependent manner in both age groups. The maximum diastolic potential was decreased by propafenone in the neonatal atrionodal tissue but not in other regions of the AVN and not in any region of the adult AVN. Action-potential duration was increased in all regions of the AVN in both age groups. Action-potential amplitude and maximum upstroke velocity were decreased by propafenone in both age groups. Unlike other excitable tissues of the heart, the action-potential duration of AVN nodal cells increased with decreasing pacing intervals as the pacing interval approached the Wenckebach interval.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Summary: Purpose: A prospective series of 643 persons with epilepsy attending a reference neurologic center in Medellin, Colombia, was examined by computed tomography (CT scan) or serology or both with the enzyme-linked immunoelectrotransfer blot assay (EITB) to assess the prevalence of Taenia solium cysticercosis. Methods: All presenting patients were consecutively enrolled in the study. Five hundred forty-six persons underwent cerebral CT scans; 376 of them also had serum EITB performed. Results: Prevalence of neurocys@ercosis by CT scan was 13.92%. Overall prevalence of T. solium antibodies with EITB was 9.82%, but for those with late-onset epilepsy (onset after age 30 years), prevalence increased to 17.5% and 19% for those who originated from outside urban Medellin. Seroprevalence in individuals with mixed lesions (cysts and calcifications) was 88.2% and 64.10% in those with live cysts. Conversely, only 2.72% of persons with CT findings not related to neurocysticercosis had positive EITB tests. Conclusions: Our study shows that an important proportion of individuals with epilepsy have radiologic or serologic evidence of T. solium infection, suggesting that neurocysticercosis is an important etiology for epilepsy in Colombia.  相似文献   
3.
Sol-gel transition temperature-controllable Pluronic F127/F68 mixtures including mildly crosslinked alginate and nonsteroidal anti-inflammatory drug (ibuprofen) were prepared to evaluate their potential as tissue adhesion barrier gels. The sol-gel transition temperatures of the Pluronic mixtures could be controlled by adjusting F127/F68 ratio and polymer concentration. The mildly crosslinked alginate with still flow property provided the residence stability of Pluronic mixture gels in the body. Ibuprofen was loaded in Pluronic mixtures to reduce inflammatory response in the body and, thus, to prevent tissue adhesion. The gelation temperatures of the Pluronic mixtures were not affected by the alginate but lowered by the addition of ibuprofen. The in vitro drug release behavior and in vivo peritoneal tissue adhesion of the Pluronic mixtures with the sol-gel transition just below body temperatures were investigated. The drug release behavior from the ibuprofen (1 wt%)-loaded Pluronic mixture gels at 37 degrees C was examined using a membrane-less dissolution model. The drug in the mixture gels was released continuously up to about 45-65% of the total loading amount during the first 7 days. For in vivo evaluation of tissue anti-adhesion potential, the Pluronic mixtures with/without drug were coated on the peritoneal wall defects of rats and their tissue adhesion extents and tissue reactions (inflammatory response, granulation tissue formation, and toxicity in organs) were compared. It was observed that ibuprofen has a positive effect for the peritoneal tissue anti-adhesion. The Pluronic F127/F68/alginate/ibuprofen mixture gel (25 wt% of F127/F68 [7/3], 1 wt% ibuprofen) was highly effective for the prevention of peritoneal tissue adhesion and showed a relatively low inflammatory response and non-toxicity, and thus can be a good candidate material as a coatable or injectable tissue adhesion barrier gel.  相似文献   
4.
Listeria monocytogenes causes major food-borne outbreaks of disease worldwide. Specific identification of this microorganism is of utmost importance to public health and industry. Listeria species are known to secrete a 60-kDa protein collectively termed p60, which is encoded by the iap (invasion-associated protein) gene and secreted in large quantities into the growth media. p60 is a highly immunogenic murein hydrolase that is essential for cell division. Due to these properties, p60 is an ideal diagnostic target for the development of immunological detection systems for L. monocytogenes. We report here two independent lines of monoclonal antibody (MAb): p6007, which specifically recognizes L. monocytogenes p60, and p6017, which reacts with a wide range of Listeria p60 proteins. By combining these antibodies with a polyclonal antibody, we developed efficient sandwich enzyme-linked immunosorbent assay (ELISA) systems which can specifically identify L. monocytogenes or generally detect Listeria species. Since an excess amount of the peptide corresponding to PepA or PepD did not interfere with the ELISA, and direct ELISAs were unable to detect both peptides, we concluded that the epitope presumed to be recognized by p6007 or p6017 could be distinguished from PepA and PepD as described by Bubert et al. (Appl. Environ. Microbiol. 60:3120-3127, 1997). To our best knowledge, this is the first example of an immunological identification system that uses p60-recognizing MAbs.  相似文献   
5.
The objective was to test the hypothesis that the optimal cryoprotective agent for cryopreservation of human spermatozoa would be a solute for which cells have the highest plasma membrane permeability, resulting in the least amount of volume excursion during its addition and removal. To test this hypothesis, theoretical simulations were performed using membrane permeability coefficients to predict optimal procedures for the addition and removal of a cryoprotectant. Simulations were performed using data from four different cryoprotectants: (i) glycerol, (ii) dimethyl sulphoxide, (iii) propylene glycol and (iv) ethylene glycol. Thermodynamic formulations were applied to determine approaches for the addition and removal of 1 M and 2 M final concentrations of cryoprotectant, allowing the spermatozoa to maintain a cell volume within their osmotic tolerance limits. Based on these data, ethylene glycol was predicted to be optimal for minimizing volume excursions among the solutes evaluated. These predictions were then experimentally tested using glycerol as the control cryoprotectant and ethylene glycol as the experimental cryoprotectant. The results indicate that there was a higher (P < 0.05) recovery of motile spermatozoa after cryopreservation when using 1 M ethylene glycol than with 1 M glycerol, supporting the hypothesis that use of the cryoprotectant for which the cell has the highest permeability will result in higher cell survival.   相似文献   
6.
PurposeOral adsorbents delay disease progression and improve uremic symptoms in patients with chronic kidney disease (CKD). DW-7202 is a newly developed oral adsorbent with high adsorptive selectivity for uremic toxins. We evaluated patient preference for and adherence to DW-7202 versus AST-120 therapy and compared treatment efficacy and safety in patients with pre-dialysis CKD.Materials and MethodsA seven-center, randomized, open-label, two-way crossover, active-controlled, phase IV clinical trial was conducted. Patients with stable CKD were randomly assigned to receive DW-7202 (capsule type) or AST-120 (granule type) for 12 weeks. The groups then switched to the other adsorbent and took it for the next 12 weeks. Patient preference was the primary outcome. Secondary outcomes included changes in estimated glomerular filtration rate (eGFR) and serum creatinine, cystatin C, and indoxyl sulfate (IS) levels.ResultsSignificantly more patients preferred DW-7202 than AST-120 (p<0.001). Patient adherence improved after switching from AST-120 to DW-7202; there was no apparent change in adherence after switching from DW-7202 to AST-120. Changes in eGFR and serum creatinine, cystatin C, and IS levels were not significantly different according to adsorbent type. There was also no significant difference in the incidences of adverse events during treatment with DW-7202 and AST-120.ConclusionDW-7202 can be considered as an alternative to AST-120 in patients who cannot tolerate or show poor adherence to granule type adsorbents. Further studies to evaluate factors affecting patient preferences and improved adherence are warranted (Clinical trial registration No. NCT02681952).  相似文献   
7.
The aim of this study was to determine the relationship between calcium ionophore A23187-induced acrosome reaction (AR) and sperm fertilizing ability. Semen samples remaining after preparation for standard IVF were studied in 109 patients who had sperm concentrations > or =20 x 10(6)/ml. Ionophore-induced AR was performed on motile spermatozoa selected by centrifugation on a Percoll gradient. Semen analysis was performed using standard methods. Patients with higher (>50%, n = 76) fertilization rates had significantly higher ionophore-induced AR than patients with lower (<50%, n = 33) fertilization rates (49 +/- 14 versus 38 +/- 21%, P < 0.05). When the data from all patients were analysed by logistic regression, only the percentage sperm motility in insemination medium and ionophore-induced AR were significantly related to fertilization rates. Similar results were also obtained when the data from a subgroup of patients with poor (<15% normal) sperm morphology were analysed. However, when patients with normal sperm morphology > or =15% were analysed separately, only sperm count and the percentage of spermatozoa with progressive motility in semen were significantly related to fertilization rates. In conclusion, ionophore- induced AR was significantly related to fertilization rates in vitro mainly in patients with teratozoospermic semen. Tests for ionophore- induced AR may provide additional information about sperm fertilizing ability but may not indicate specific defects of the physiological AR.   相似文献   
8.
Supravalvular aortic stenosis (SVAS) is an inherited obstructive vascular disease that affects the aorta, carotid, coronary and pulmonary arteries. Previous molecular genetic data have led to the hypothesis that SVAS results from mutations in the elastin gene, ELN. In these studies, the disease phenotype was linked to gross DNA rearrangements (35 and 85 kb deletions and a translocation) in three SVAS families. However, gross rearrangements of ELN have not been identified in most cases of autosomal dominant SVAS. To define the spectrum of ELN mutations responsible for this disorder, we refined the genomic structure of human ELN and used this information in mutational analyses. ELN point mutations co-segregate with the disease in four familial cases and are associated with SVAS in three sporadic cases. Two of the mutations are nonsense, one is a single base pair deletion and four are splice site mutations. In one sporadic case, the mutation arose de novo. These data demonstrate that point mutations of ELN cause autosomal dominant SVAS.   相似文献   
9.
In order to develop a structured and objective diagnostic instrument, authors completed: (1) the translation and back translation of the Korean version of the Kiddie-Schedule for Affective Disorders and Schizophrenia - Present and Lifetime Version (K-SADS-PL) and (2) the examination of its validity and reliability of the K-SADS-PL-Korean version (K-SADS- PL) when used with Korean children. A total of 91 study subjects were recruited from child and adolescent psychiatry outpatient clinics. Clinical diagnoses were used as a gold standard for the examination of validity of K-SADS-PL-K. Consensual validity of threshold and sub-threshold diagnoses were good to excellent for attention-deficit/hyperactivity disorder (ADHD), fair for tic and oppositional defiant disorders, and poor to fair for anxiety and depressive disorders. Inter-rater and test-retest reliabilities were fair to excellent for ADHD and tic disorder. The significant correlations between the K-SADS-PL-K and Korean Child Behavior Checklist (K-CBCL) were found, which provided additional support for the concurrent validity of the K-SADS-PL-K. Sensitivities varied according to the diagnostic categories, but specificities remained high over all diagnoses, suggesting that the K-SADS-PL-K is a desirable confirmatory diagnostic tool. The results of this study suggest that the K-SADS-PL-K is an effective instrument for diagnosing major child psychiatric disorders, including ADHD, behavioral disorders and tic disorders in Korean children. Future studies will examine the validity and reliability of the K-SADS-PL-K in larger samples, including adolescents and community samples on a variety of child and adolescent psychiatric disorders.  相似文献   
10.
X-linked severe combined immunodeficiency (X-SCID) is a rare, life-threatening immune disorder, caused by mutations in the gamma c chain gene, which encodes an essential component of the cytokine receptors for interleukin-2 (IL-2), IL-4, IL-7, IL-9, IL-15, and IL-21. A 13-month-old boy with recurrent infections who had reduced serum immunoglobulin levels and decreased numbers of CD3, CD16/56 cells was evaluated for gamma c chain gene mutation and protein expression. The patient had a C-to-T point mutation at nucleotide position 690, one of the hot spots, resulting in a single amino acid substitution of cysteine for arginine (R226C), as determined by direct sequencing and PCR-RFLP. The patient's mother was a heterozygous carrier. Percutaneous umbilical cord blood sampling was performed at the 6-month of gestation in a subsequent pregnancy. As the immunophenotype of the fetus showed an identical pattern, the pregnancy was terminated and genetic analysis of the abortus confirmed recurrence. This is the first report of the molecular diagnosis of X-SCID in Korea. Genetic analysis of the gamma c chain gene is useful for definite diagnosis and genetic counseling for X-SCID.  相似文献   
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