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Sympathetic skin responses from postauricular region in Meniere's disease.   总被引:10,自引:0,他引:10  
OBJECTIVE: To investigate the sympathetic nervous system activity in Meniere's disease (MD) by recording sympathetic skin responses (SSRs) from the postauricular region (PA). METHODS: Twenty-one patients with definite unilateral MD diagnosis and 12 healthy volunteers were studied by evoking right and left PA-SSRs with electrical stimulation of the left median nerve at the wrist in attack and interval periods of MD. Mean latencies and maximum amplitudes were used in statistical analyses. RESULTS: In unilateral definite MD patients, the mean latencies were longer and the maximum amplitudes were smaller on the involved ear side than those on the normal ear side (p<0.01 for both amplitude and latency) and than those from the controls (p<0.01 and p<0.05). In three patients, there was no detectable PA-SSR on the involved ear side while there were SSRs on the healthy side. In four patients, the responses were absent bilaterally during the attack period. CONCLUSIONS: There is a marked asymmetric sympathetic hypofunction in the area of the PA region of the involved ear in MD patients. SIGNIFICANCE: The PA region is a new site for recording sympathetic skin responses. PA-SSR is a useful tool to investigate sympathetic nervous system function in MD patients.  相似文献   
3.
Leukocyte arylsulphatase A (AS-A) was shown to be significantly high in newly-diagnosed breast cancer patients. Previous reports imply a connection between serum interleukin-6 (IL-6) and breast cancer, possibly through a modulation of enzymes involved in estrogen synthesis. Abnormal distribution of heparan sulphate proteoglycans (HSPGs) in malignant breast epithelial cells suggests that they play a key role in the regulation of cell growth. Estradiol is believed to be effective in modulating glycosaminoglycans (GAGs) and their depolymerizing enzymes. Therefore, in this study, attempts were made to evaluate the activity of leukocyte arylsulphatase A, serum interleukin-6, urinary GAGs and heparan sulphate (HS) in response to tamoxifen (TAM) therapy in mastectomised breast cancer patients. Thirty-four patients (aged 30-82 years) were administered TAM (20 mg twice daily). Blood and urine samples of each patient were collected three times (at the beginning, and in third and sixth month of TAM therapy), and biochemical parameters were measured. There was no difference between baseline leukocyte AS-A activity and that measured after three months. At the end of six months, enzyme activity was significantly higher than the former values (p=0.022), but within the reference intervals reported in the literature. Although this increase might imply a normalization, the duration of TAM therapy is not long enough to make a decision about either regression or aggravation of the disease. TAM did not have any effect on serum IL-6, urinary HS and GAG levels which may be due to insensitivity of these variables to TAM during the short period of therapy. Both urinary GAG and HS levels measured at sixth month exhibited a positive correlation with the baseline level of leukocyte AS-A (p=0.005 and 0.009, respectively), suggesting that positive responses to the drug might be seen in patients with low AS-A activity.  相似文献   
4.
We report a fluid level in an acute extradural haematoma developing after placement of a ventriculoperitoneal shunt for hydrocephalus. This fluid level was thought to be due to a mixture of blood and cerebrospinal fluid.  相似文献   
5.

Background

Peanut allergy has a rising prevalence in high-income countries, affecting 0.5%–1.4% of children. This study aimed to better understand peanut anaphylaxis in comparison to anaphylaxis to other food triggers in European children and adolescents.

Methods

Data was sourced from the European Anaphylaxis Registry via an online questionnaire, after in-depth review of food-induced anaphylaxis cases in a tertiary paediatric allergy centre.

Results

3514 cases of food anaphylaxis were reported between July 2007 - March 2018, 56% in patients younger than 18 years. Peanut anaphylaxis was recorded in 459 children and adolescents (85% of all peanut anaphylaxis cases). Previous reactions (42% vs. 38%; p = .001), asthma comorbidity (47% vs. 35%; p < .001), relevant cofactors (29% vs. 22%; p = .004) and biphasic reactions (10% vs. 4%; p = .001) were more commonly reported in peanut anaphylaxis. Most cases were labelled as severe anaphylaxis (Ring&Messmer grade III 65% vs. 56% and grade IV 1.1% vs. 0.9%; p = .001). Self-administration of intramuscular adrenaline was low (17% vs. 15%), professional adrenaline administration was higher in non-peanut food anaphylaxis (34% vs. 26%; p = .003). Hospitalization was higher for peanut anaphylaxis (67% vs. 54%; p = .004).

Conclusions

The European Anaphylaxis Registry data confirmed peanut as one of the major causes of severe, potentially life-threatening allergic reactions in European children, with some characteristic features e.g., presence of asthma comorbidity and increased rate of biphasic reactions. Usage of intramuscular adrenaline as first-line treatment is low and needs to be improved. The Registry, designed as the largest database on anaphylaxis, allows continuous assessment of this condition.
  相似文献   
6.
Sera from 530 children suffering from various diseases and from 64 controls were tested for smooth muscle autoantibodies (SMA) by indirect immunofluorescence. A high incidence of SMA (51-86%) was found in patients with viral and bacterial infections (viral hepatitis, infectious mononucleosis, measles, mumps, chickenpox, typhoid fever, and brucellosis), independently of liver invovlvement, and in patients with acute haemolytic anaemia due to G-6-PD deficiency (48%). By contrast, the incidence of SMA from patients with beta-thalassaemia major and idiopathic thrombocytopenic purpura was no higher than in the controls. The discrepancy in incidence in haemolytic anaemias due to different causes may reflect the effect of endogenous and extrinsic agents. In the viral infections, SMA were mainly of the IgM class and gave an 'SMA-V' staining pattern. In bacterial infections (typhoid fever and brucellosis), SMA were either IgG only or IgM and IgG, and the staining pattern was also mainly 'SMA-V'. In infections which affect or may affect the liver (viral hepatitis, infectious mononucleosis, typhoid fever, and brucellosis), SMA was present at high titres (1:80-1:320), whereas in infections not affecting the liver (measles, mumps, and chickenpox) the titres were lower (less than or equal to 1:80). In most patients SMA occurred transiently and without apparent pathogenetic significance. The antigen against which infection-induced SMA is directed is not actin; its nature has yet to be identified.  相似文献   
7.
Based on direct sequencing information from 5UTR and NS5B regions, we identified subtype 1b as a predominant hepatitis C virus genome in Turkey, which affected more than 91% of 79 patients studied. Next, the full genome sequence of a Turkish 1b isolate was obtained by the cloning of polypeptide-encoding region into 7 overlapping fragments. Turkish 1b isolate, which was named HCV-TR1, comprises 9361 nucleotides, including 306 nucleotides of 5UTR, a single long open reading frame of 9033 nucleotides, and 22 nucleotides of 3UTR. When compared to HCV 1b polypeptide sequences available at GenBank, the predicted polypeptide displayed a total of 36 amino acid substitutions, of which 16 was specific for HCV-TR1 isolate. Despite these changes, major structural and functional motifs of HCV proteins were maintained in HCV-TR1. In contrast, HCV-TR1 displayed amino acid substitutions in 6 out of 9 major cytotoxic T-cell epitopes. These data suggest that HCV-TR1 encodes functionally intact viral proteins, but it also encodes altered viral epitopes, which may affect host immune-response.  相似文献   
8.
A blood culture cohort study investigating issues related to isolation of coagulase-negative staphylococci (CoNS) and other skin microflora is reported. Data were collected over 12 weeks to determine the incidence of significant CoNS bacteremia versus that of pseudobacteremia (contaminants) and to evaluate drug therapy in patients with cultures positive for CoNS. In addition, the effectiveness of 0.2% chlorine peroxide as a bactericidal disinfectant was compared to that of 10% providone iodine. A total of 3,276 cultures of blood from 1,433 patients were evaluated in the study. Eighty-nine cultures were positive for skin flora, with 81 of 89 (91%) involving CoNS. The incidence of significant CoNS bacteremia was 20 of 81 (24.7%), that of indeterminate bacteremia was 10 of 81 (12.3%), and that of contamination was 59 of 81 (72.8%). The incidence of significant bacteremia involving CoNS was double the 10 to 12% rate based on previous estimations at our institutions. In tests with the two bactericidal disinfectants, 22 of 1,639 cultures (1.3%) in the chlorine peroxide group versus 37 of 1,637 (2.3%) in the providone iodine group were considered contaminated (P = 0.065). Rates of contamination for venipuncture versus catheter collection were not significantly different (P = 0.46). The overall contamination rate was 59 of 3,276 (1.8%), which is consistent with the lower end of published quality assurance benchmark standards. The low rate was believed to be due to the professional phlebotomy staff in our institutions. There was excellent agreement between retrospective analysis by reviewers, when formal criteria were used, and the attending physicians’ intuitive clinical impressions in the classification of significant bloodstream infections (100% agreement) or contamination (95% agreement). However, physicians still used antimicrobial agents to treat nearly one-half of the patients with contaminated blood cultures, with vancomycin being misused in 34% of patients. In addition, 10% of patients with significant bacteremia were treated with inappropriate agents. There were no significant adverse events or prolonged hospital stays due to the unnecessary use of vancomycin; however, the additional costs of treating patients whose cultures contained CoNS contaminants was estimated to be $1,000 per patient. Measures to limit the unnecessary use of vancomycin (and other agents) are important.Coagulase-negative staphylococci (CoNS), the most frequent blood culture isolates, are predominantly blood culture contaminants, but they are also a significant cause of bacteremia (25, 7, 9, 13). Institution-specific contamination rates vary from 2 to more than 6% (3, 5, 23, 26, 27). In the past 5 years, estimated contamination rates at our hospitals ranged from 2.5 to 3.5%. During this period, CoNS accounted for 45 to 60% of total blood isolates, and we estimated, using laboratory criteria, that 10 to 12% of CoNS isolates from blood were implicated in significant bloodstream infections. A relatively large proportion of the patient population with presumed false-positive blood cultures due to contaminants (pseudobacteremia) were treated with antimicrobial agents, in particular, vancomycin.Clinical and microbiologic guidelines for the differentiation of true bacteremia from pseudobacteremia or contamination have been published (5, 13, 15). Suggested laboratory criteria for true bacteremia include growth within 48 h and multiple blood cultures positive for the same organism. In contrast, increased duration of time before positivity, polymicrobial growth of skin organisms, or growth during antibiotic treatment suggest contamination. Others recommended that the addition of clinical guidelines is essential for the appropriate classification of bacteremia (4, 8, 9, 15, 18).We conducted a cohort study to evaluate clinical and laboratory data for adult patients with blood cultures positive for CoNS. The study was done at two tertiary-care teaching centers, Deaconess Medical Center (DMC) and Sacred Heart Medical Center (SHMC), with a combined capacity of 900 beds. We examined problems associated with false-positive bacteremia and determined the incidence of significant bacteremia. Our goal was to make recommendations to improve clinicians’ ability to recognize the significance of potentially contaminating organisms and to evaluate treatment given to patients with CoNS-positive blood cultures. To attempt to minimize contamination, we evaluated the nontoxic, antiseptic and disinfectant chlorine peroxide in comparison to a standard disinfectant.(This work was previously presented in abstract form at the 96th General Meeting of the American Society for Microbiology, New Orleans, La., 19 to 23 May 1996 [24a].)  相似文献   
9.
3-Hydroxysteroid-dehydrogenase (3-HSD) is an isoenzyme that catalyses an essential step in the synthesis of all classes of active steroid hormones. The presence of steroid hormones of the vertebrate type in invertebrates is acknowledged in addition to a group of steroid-like hormones called ecdysteroids that were present in arthropods and helminths. In the present study, 3-HSD was detected in the bradyzoites enclosed in sarcocysts of Sarcocystis spp. with immunohistochemistry. The results suggest that self-originating steroid hormones may play important roles in the development of Sarcocystis spp., and possibly in the regulation of the reciprocal immune interaction between the host and these parasites.  相似文献   
10.
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