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21.
We identified two afibrinogenemic girls in two Japanese families and performed molecular analysis to clarify the mechanisms of fibrinogen defects. Genetic analyses were performed by PCR amplification of the fibrinogen gene and DNA sequence analysis. To analyze the mechanisms of mature fibrinogen defects in plasma, we cloned minigenes from the proposita's PCR-amplified DNA, transfected them into CHO cells, and sequenced the cDNA amplified with the RT reaction followed by PCR. Sequence analyses indicated that one was caused by a homozygous 1238?bp deletion of the fibrinogen Aα-chain gene (FGAΔ1238) and the other was a compound heterozygous FGAΔ1238 and novel FGA c.54+3A>C substitution. The minigene corresponding to FGAΔ1238 generates two aberrant mRNAs, both of which may induce a frameshift and terminate prematurely. In contrast, the minigene corresponding to FGA c.54+3A>C generates two aberrant mRNAs, one of which may induce a frameshift and terminate prematurely, and the other uses a cryptic 5' splice site in exon 1, resulting in the deletion of six amino acids in signal peptides. Molecular analyses of both genetic variants suggest that the lack of a mature Aα-chain, impaired assembly, and/or secretion of the fibrinogen molecule may lead to afibrinogenemia.  相似文献   
22.
Cysteinyl leukotriene and leukotriene receptor occupancy have been linked to several processes in seasonal allergic rhinitis (SAR), including nasal congestion, rhinorrhea, and recruitment of inflammatory cells. We investigated whether add-on loratadine, an antihistamine, might be effective for SAR patients showing unsatisfactory control of symptoms with the leukotriene receptor antagonist (LTRA) montelukast alone. Patients with SAR caused by Japanese cedar pollen (SAR-JCP; mean age, 29.4 years) were given prophylactic montelukast for 1 month before peak JCP dispersal. Patients recorded the severity of the symptoms (sneezing, rhinorrhea, nasal congestion, and ocular symptoms) daily on visual analog scale (VAS). We selected patients with VAS scores of >50 for any of the symptoms just before the peak pollen season (March 2 to March 8) and designated them as "poorly controlled" patients. Then, in the peak JCP season (from March 9), we conducted a randomized, double-blind, placebo-controlled study to determine whether add-on loratadine might be effective for these "poorly controlled" patients. Montelukast alone was effective, as evaluated by improvement of the VAS scores, in 95 of the 137 patients (69.3%). Add-on loratadine significantly decreased the total scores for nasal symptoms (p < 0.05), sneezing (p < 0.05), and rhinorrhea (p < 0.05) when compared with placebo. The symptoms of SAR in two of three SAR-JP patients could be controlled (VAS score[s] under 50) by prophylactic treatment with montelukast alone under the condition of mild JCP dispersal. Furthermore, the effect of add-on antihistamine on sneezing and rhinorrhea was found in selected SAR-JCP patients.  相似文献   
23.
Tonic gonadotrophin secretion throughout the menstrual cycle is regulated by the negative‐feedback actions of ovarian oestradiol (E2) and progesterone. Although kisspeptin neurones in the arcuate nucleus (ARC) of the hypothalamus appear to play a major role in mediating these feedback actions of the steroids in nonprimate species, this issue has been less well studied in the monkey. In the present study, we used immunohistochemistry and in situ hybridisation to examine kisspeptin and KISS1 expression, respectively, in the mediobasal hypothalamus (MBH) of adult ovariectomised (OVX) rhesus monkeys. We also examined kisspeptin expression in the MBH of ovarian intact females, and the effect of E2, progesterone and E2 + progesterone replacement on KISS1 expression in OVX animals. Kisspeptin or KISS1 expressing neurones and pronounced kisspeptin fibres were readily identified throughout the ARC of ovariectomised monkeys but, on the other hand, in intact animals, kisspeptin cell bodies were small in size and number and only fine fibres were observed. Replacement of OVX monkeys with physiological levels of E2, either alone or with luteal phase levels of progesterone, abolished KISS1 expression in the ARC. Interestingly, progesterone replacement alone for 14 days also resulted in a significant down‐regulation of KISS1 expression. These findings support the view that, in primates, as in rodents and sheep, kisspeptin signalling in ARC neurones appears to play an important role in mediating the negative‐feedback action of E2 on gonadotrophin secretion, and also indicate the need to study further their regulation by progesterone.  相似文献   
24.
In order to clarify the characterization of phenotypes of paroxysmal nocturnal haemoglobinuria (PNH) erythrocytes (E), we analysed the expression of decay accelerating factor (DAF) and CD59/membrane attack complex inhibition factor (MACIF) on the membrane surface of PNH-E by means of the flow cytometric method using anti-DAF and/or CD59/MACIF monoclonal antibodies in nine PNH-patients. In two-colour analysis, this expression of PNH-E was classified into three fractions; negative, intermediate and positive according to intensity. The negative fraction was classified into two groups; one group an exclusively negative population, and the other a negative population having slightly DAF-positive E. The intermediate fraction was recognized on PNH-E of cases with PNH II-E and extremely heterogenous. In the positive fraction, this expression was almost the same as on normal E except for case 8. In single-colour analysis for DAF or CD59/MACIF, three fractions were classified as well as the definition in two-colour analysis. In single-colour analysis, the expression on PNH-E was also heterogenous in each fraction and among PNH-patients. However, the intermediate fraction for CD59/MACIF was not found on PNH-E of cases without PNH II-E, although intermediate fraction for DAF was recognized on PNH-E of some cases with PNH III-E in addition to those with PNH II-E. The results suggest that expression of CD59/MACIF and DAF on the membrane surface of PNH-E phenotypes is heterogenous and varies among PNH patients.  相似文献   
25.
Although both atrial fibrillation (AF) and decreasing glomerular filtration rate (GFR) are strongly related to advanced age and share common associated vascular risk factors, few studies have explored the relation between AF and GFR. From residents (age >or=40 years) in Kurashiki City, a total of 41,417 subjects (median age 72 years; 13,956 men) were enrolled in the Kurashiki City Annual Medical Survey from May to December 2006. The estimated overall prevalence of AF was 1.6% (2.8% in the low-GFR tertile, 1.2% in the middle tertile, and 0.9% in the high tertile, p <0.001). After all subjects were categorized into age tertiles (age thresholds 68 and 76 years), AF was identified in 0.9% in the low-GFR tertile, 0.6% in the middle tertile, and 0.5% in the high tertile in the low-age tertile (p = 0.018); 2.6% in the low-GFR tertile, 1.2% in the middle tertile, and 1.1% in the high tertile in the middle-age tertile (p <0.001); and 3.9% in the low-GFR tertile, 2.4% in the middle tertile, and 1.7% in the high tertile in the high-age tertile (p <0.001). The odds ratio for AF adjusted for age, gender, vascular risk factors, cardiac disease, and hemoglobin was 1.91 (95% confidence interval 1.54 to 2.38, p <0.001) for the low-GFR tertile versus the high tertile and 1.12 (95% confidence interval 0.88 to 1.42, p = 0.364) for the middle-GFR tertile versus the high tertile. The prevalence of AF gradually increased with decreasing GFR. In conclusion, AF appears to be associated with decreasing GFR.  相似文献   
26.
We performed a flow cytometric analysis using monoclonal antibodies to decay accelerating factor (DAF) and CD59/membrane attack complex inhibitory factor (CD59/MACIF) in order to investigate the leukemic cells and erythrocytes from a patient with paroxysmal nocturnal hemoglobinuria (PNH) who developed acute myelocytic leukemia. In May 1990, the leukemic cells comprised 70% of the mononuclear cells in the bone marrow and 76% of those in the peripheral blood. They consisted of a mixture of positive and negative populations, including single DAF- positive cells. In August 1990, almost 100% of the peripheral mononuclear cells were leukemic blasts, and these consisted of a single population with reduced DAF expression. Single-color flow cytometric analysis showed that the leukemic cells lacked CD59/MACIF, while control leukemic cells (n = 3) expressed both DAF and CD59/MACIF. Leukemic blasts from this patient and six control patients expressed lymphocyte function-associated antigen 3 and FcIII receptors (CD 16) both before and after treatment with phosphatidylinositol-specific phospholipase C. The patient's erythrocytes lacking DAF and CD59/MACIF expression corresponded to the proportion of complement-sensitive cells at the onset of acute leukemia. These DAF- and CD59/MACIF-deficient erythrocytes disappeared almost completely with progression of the leukemia. In conclusion, it appears that the expression of glycosylphosphatidylinositol-linked membrane proteins by leukemic cells was heterogeneous and discordant in our patient, and that the leukemic cells were derived from the PNH clone because of their deficiency of CD59/MACIF. It is also suggested that DAF could compete more effectively than CD59/MACIF for a limited number of anchor molecules available on the proliferating leukemic cells.  相似文献   
27.
A 38 year-old man was admitted to our hospital with the chief complaint of epigastralgia. His laboratory data revealed leukocytosis and increased serum amylase, and abdominal ultrasonography revealed diffuse swelling of the pancreas. Thus, he was diagnosed as having acute pancreatitis. Moreover, abdominal computed tomography showed pneumobilia in the gallbladder and the common bile duct. Gastroduodenal fiberscopy demonstrated peptic ulcer scars around a foramen with smooth margins at the anterior wall of the duodenal bulb. The bile juice flowed from the bottom of the foramen. Endoscopic retrograde cholangiopancreatography revealed the fistula between the common bile duct and the anterior wall of the duodenal bulb, but not the posterior wall. However, there was no pancreatico-biliary maljunction and no stones in the gallbladder or bile duct. This is a rare case of choledochoduodenal fistula at the anterior wall of the duodenal bulb caused by duodenal peptic ulcer disease.  相似文献   
28.
BACKGROUND: In patients with chronic heart failure (CHF), circadian variability of RR and QT intervals may be altered because of neurohumoral activation and functional and structural remodeling of the heart. OBJECTIVE: The aim of this study was to evaluate the prognostic significance of circadian variability of the RR and QT intervals and QT dynamicity (QT/RR slope) in CHF patients. METHODS: We prospectively enrolled 121 patients with stable CHF in sinus rhythm (age 67 +/- 14 years, mean +/- SD; range 34 to 87 years). The RR, QT, and rate-corrected QT (QTc) intervals and the QT/RR slope measured from 24-hour Holter electrocardiogram were fitted by cosine curves. RESULTS: During the follow-up period of 34 +/- 17 months, 40 (33%) patients died of cardiac causes, 10 of which were sudden. All patients showed significant circadian rhythms in the RR, QT, and QTc intervals and the QT/RR slope by cosine-curve fitting. In addition to the expected higher heart rate, longer QT interval, and steeper QT/RR slope, we found that patient who died of cardiac causes had reduced circadian variability of QT interval (10 +/- 10 ms vs 21 +/- 13 ms) and a later maximum RR interval (4.1 +/- 0.9 AM vs 2.3 +/- 2.1 AM) compared with survivors, among many other statistically significant circadian parameter differences. These 2 parameters were independent predictors of cardiac death in multivariate Cox proportional hazards regression analysis. CONCLUSION: Circadian variability analyses of Holter-derived RR and QT intervals may provide prognostic information beyond that provided by 24-hour averages of these parameters.  相似文献   
29.
Background:Rapid-onset, acute hypernatremia caused by sodium overload is a rare, life-threatening condition. Although experts recommend rapid correction of sodium concentration [Na] based on pathophysiological theories, only a few reports have documented the specific details of sodium correction methods. The objective of this study was to systematically review the reported treatment regimens, achieved [Na] correction rates, and treatment outcomes.Methods:PubMed, Ichushi-database, and references without language restrictions, from inception to January 2021, were searched for studies that described ≥1 adult (aged ≥18 years) patients with rapid-onset hypernatremia caused by sodium overload, whose treatment was initiated ≤12 hours from the onset. The primary outcome of interest was the [Na] correction rate associated with mortality.Results:Eighteen case reports (18 patients; median [Na], 180.5 mEq/L) were included. The cause of sodium overload was self-ingestion in 8 patients and iatrogenic sodium gain in 10 patients; baseline [Na] and symptoms at presentation were comparable for both groups. Individualized rapid infusion of dextrose-based solutions was the most commonly adopted fluid therapy, whereas hemodialysis was also used for patients already treated with hemodialysis. The correction rates were more rapid in 13 successfully treated patients than in 5 fatal patients. The successfully treated patients typically achieved [Na] ≤160 within 8 hours, [Na] ≤150 within 24 hours, and [Na] ≤145 within 48 hours. Hyperglycemia was a commonly observed treatment-related adverse event.Conclusion:The limited empirical evidence derived from case reports appears to endorse the recommended, rapid, and aggressive sodium correction using dextrose-based hypotonic solutions.  相似文献   
30.
In vivo luteinizing hormone releasing hormone (LHRH) release was measured in conscious, ovariectomized rhesus monkeys using a push-pull cannula inserted into the stalk-median eminence, and the relationship between sampling location and LHRH release was examined. Within an individual animal in which multiple experiments were conducted with different cannula placements, LHRH pulse frequency was consistent. In contrast, LHRH pulse amplitude and mean LHRH release varied with cannula tip location in a pattern which reflected the anatomical distribution of LHRH-immunoreactive fibers described for the rhesus monkey. These results suggest that our push-pull perfusion method is reliable for the in vivo measurement of LHRH and perhaps other neuropeptides and/or neurotransmitters, as well.  相似文献   
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