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21.
Altintaş DU Karakoç GB Yilmaz M Pinar M Kendirli SG Cakan H 《Clinical & developmental immunology》2004,11(1):87-96
BACKGROUND: Aeroallergen sampling provides information regarding the onset, duration and severity of the pollen season that clinicians use to guide allergen selection for skin testing and treatment. OBJECTIVES: This atmospheric survey reports (1) airborne pollen contributions in Adana in one-year period (2) pollen onset, duration and peak level (3) the relationship between airborne pollen and selected meteorological variables and; (4) effects on symptoms in pollen allergic children. METHODS: Pollen sampling was performed with a volumetric Burkard Spore Trap. Meteorological data were measured daily from April 2001 to April 2002. Asthma symptom scores were investigated in 186 pollen allergic children that were on follow up in pediatric allergy outpatient clinics during same period. RESULTS: Average measurements included 82.5% tree pollen, 7.7% grass pollen and 9.8% herb pollen 54 taxa were identified during one year. The most prominent tree pollens were Cupressaceae, Eucalyptus and Pinus. The most common herb was Chenopodiaceae pollen family. When airborne pollen levels were examined in relation to single meteorological conditions; daily variations in total pollen counts were not significantly correlated with any variable studied (humidity, rainfall, temperature and wind) (p > 0.05). On the other hand, statistically significant relationship between pollen concentration and symptom scores were found (p > 0.05). Positive correlations were seen between both Gramineae and Herb pollen, and humidity and rainfall from March to July. However, positive correlations were detected between tree pollen counts and temperature and humidity in May and June. CONCLUSION: This survey is the first volumetric airborne pollen analysis conducted in the survey area in Adana. This study suggested that the effects of weather on pollen count and symptom scores in this population could not be clearly identified with the evaluation of one-year data. However, pollen counts had effect on allergic symptoms in pollen allergic children. Examination of the complex interaction of multiple whether parameters would perhaps more fully elucidate the relationship between meteorology and aerobiology and provide the clinician with information necessary to forecast pollen prevalence. An awareness of the ever chancing, local aeroallergen patterns requires regular monitoring. Such awareness serves as a useful guide in the effective testing and treatment of atopic patients. 相似文献
22.
Detection and genotyping of oocysts of Cryptosporidium parvum by real-time PCR and melting curve analysis 总被引:5,自引:0,他引:5
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Tanriverdi S Tanyeli A Başlamişli F Köksal F Kilinç Y Feng X Batzer G Tzipori S Widmer G 《Journal of clinical microbiology》2002,40(9):3237-3244
Several real-time PCR procedures for the detection and genotyping of oocysts of Cryptosporidium parvum were evaluated. A 40-cycle amplification of a 157-bp fragment from the C. parvum beta-tubulin gene detected individual oocysts which were introduced into the reaction mixture by micromanipulation. SYBR Green I melting curve analysis was used to confirm the specificity of the method when DNA extracted from fecal samples spiked with oocysts was analyzed. Because C. parvum isolates infecting humans comprise two distinct genotypes, designated type 1 and type 2, real-time PCR methods for discriminating C. parvum genotypes were developed. The first method used the same beta-tubulin amplification primers and two fluorescently labeled antisense oligonucleotide probes spanning a 49-bp polymorphic sequence diagnostic for C. parvum type 1 and type 2. The second genotyping method used SYBR Green I fluorescence and targeted a polymorphic coding region within the GP900/poly(T) gene. Both methods discriminated between type 1 and type 2 C. parvum on the basis of melting curve analysis. To our knowledge, this is the first report describing the application of melting curve analysis for genotyping of C. parvum oocysts. 相似文献
23.
Lowe CE Cooper JD Chapman JM Barratt BJ Twells RC Green EA Savage DA Guja C Ionescu-Tîrgovişte C Tuomilehto-Wolf E Tuomilehto J Todd JA Clayton DG 《Genes and immunity》2004,5(4):301-305
We have previously shown that the selection of haplotype tag single nucleotide polymorphisms (htSNPs) and their statistical analysis in a multi-locus transmission/disequilibrium test (TDT) results in a more cost-effective genotyping strategy in disease association studies of genes by minimising redundancy due to linkage disequilibrium between SNPs. Further savings can be achieved by the use of a two-stage genotyping strategy. This approach is illustrated here in conjunction with the multi-locus TDT in determining whether common alleles of the immune regulatory genes RANK and its ligand TRANCE (RANKL) are associated with type 1 diabetes (T1D). A saving of approximately 75% of potential genotyping reactions could be made with minimal loss of power. There was little evidence from our analysis for association between the TRANCE and RANK genes and T1D in the populations tested. 相似文献
24.
The aim of this study was to assess the diagnostic ability of magnetic resonance imaging (MRI) in subacromial impingement syndrome (SIS), using a physiological standard of reference. MRI of the rotator cuff (RC) and subacromial injection test (SIT), a reference standard for SIS diagnosis, were performed in 125 painful shoulders. MRI diagnostic accuracies were determined using a 2 x 2 table and the percentage values of SIS diagnosis in patients with the three Zlatkin MRI stages were determined. Shoulder function was evaluated using the Constant Scale, and results were compared for stages. The sensitivity, specificity, accuracy, positive and negative predictive values of MRI for SIS diagnosis were 98.85%, 36.84%, 80%, 78.18% and 93.33% respectively. Of the 32 patients with Zlatkin stage 1 changes in MRI, 20 (62%) had SIT approved SIS diagnosis, while 47 (79%) of the 59 patients with Zlatkin 2 and all of the 19 (100%) patients with Zlatkin 3 changes were diagnosed with SIS by SIT. Mean Constant scores were 78.04 +/- 18.3, 65.0 +/- 19.9 and 54.52 +/- 20.7 in patients with Zlatkin stages 1, 2 and 3, respectively (p < 0.05). The MRI of RC did not prove to be an excellent tool for SIT based SIS diagnosis, with its low specificity. However, the technique can give important clues, as its sensitivity and negative predictive values are high. 相似文献
25.
Ay S Tekdemir I Sayli U Elhan A Erbil KM Başar R 《Okajimas folia anatomica Japonica》1999,76(4):197-202
The radial nerve's course from the axillary region, branch patterns and the relation of the nerve to fixed anatomical landmarks in the arm region were studied in 27 embalmed intact cadavers. The radial nerve and its relation with the sulcus nervus radialis (SNR) was analyzed. The direct contact of the nerve with humerus in SNR was observed during the dissections. The following measurements were made: the total length of the humerus (the palpable uppermost point of the tuberculum majus and the lateral epicondyle); proximal safe zone (the tuberculum majus and the proximal beginning of the SNR); distal safe zone (the intercondylar axis and the middle of SNR); lateral safe zone (the lateral epicondyle and the distal end of SNR). In conclusion, it was aimed to correlate the osseus palpable landmarks of humerus with the course of the radial nerve for a safe surgery as the sulcus nervi radialis region is one of the main risky areas for the radial nerve palsies. 相似文献
26.
Derbent M Yilmaz Z Baltaci V Saygili A Varan B Tokel K 《American journal of medical genetics. Part A》2003,(2):129-135
This report describes the dysmorphic features and frequency of 22q11.2 deletion (del22q11) in 30 Turkish patients with conotruncal heart defects (CTHDs). Fluorescence in situ hybridization (FISH) analysis revealed deletions in the 22q11.2 region in nine (30%) individuals. The CTHDs in this group were tetralogy of Fallot (four cases), double-outlet right ventricle (DORV) (two cases), transposition of great arteries (two cases), and ventricular septal defect (VSD) associated with other CTHDs (one case). The frequency of del22q11 in the study group was relatively high because many of the patients with dysmorphic findings also had cardiac anomalies involving the pulmonary artery, ductus arteriosus, or the aortic arch and its main branches. Twenty of the 30 patients exhibited several dysmorphic findings. Two of the nine patients with del22q11 exhibited no apparent dysmorphic features other than sacral dimple. Interestingly, one of the patients with del22q11 had a phenotypic appearance similar to that seen in oculo-auriculo-vertebral spectrum (OAVS). This individual had left microtia, atresia of the external meatus, mandibular asymmetry, and peripheral facial nerve paralysis. His mental development was normal and there were no abnormalities on ophthalmological examination. The CTHDs in this patient were situs inversus dextrocardia, DORV, pulmonary stenosis, and VSD. Radiographs of this patient showed platybasia, complete fusion of C2-C3, and posterior fusion of the T1-T2 vertebrae. This particular case indicates that the phenotypic features of del22q11 and OAVS may overlap. 相似文献
27.
Adrian Florin Gal Vasile Rus Sanda Andrei Viorel Miclăuş 《Journal of histotechnology》2020,43(2):97-101
ABSTRACT Early detection of apoptotic cells on histological slides is of major importance for both diagnostic and research areas. In the current study, the aim was to propose a convenient method to stain the mitochondria and establish whether hepatocytes undergoing apoptosis can be identified in tissue sections using the proposed method. Liver tissue from five adult chinchillas was fixed with 10% neutral buffered formalin for Goldner’s trichrome (GT) and Groat’s iron hematoxylin and eosin (HE) stains and with Kolster’s fixative for the Heidenhain’s iron hematoxylin procedure. The HE and GT-stained sections showed the morphological features consistent with apoptosis i.e., homogenous intensely acidophilic cytoplasm, cell shrinkage with an irregular outline, nuclear shrinkage with cloudy karyoplasm, and karyopyknosis in the late stage. Sections stained with Heidenhain’s iron hematoxylin method was used to pinpoint mitochondria and revealed cells which were undergoing the first stages of the apoptosis process i.e., disappearance of mitochondria from the cell, chromatin condensation and margination, paracentral localization of nucleoli, and vacuolated nuclei. In more advanced stages of apoptosis, cells presented significant nuclear and cytoplasmic changes. It was concluded that this is the first report targeting the mitochondria, by performing inexpensive histological staining techniques, in order to assess dead cells in situ. 相似文献
28.
Oztürk G Ertaş FN Akyilmaz E Dinçkaya E Tural H 《Artificial cells, blood substitutes, and immobilization biotechnology》2004,32(4):637-645
A biosensor for specific determination of hydrogen peroxide was developed by using homogenized artichoke (Cynara scolymus L.) tissue in combination with a dissolved oxygen probe and applied in determination of hydrogen peroxide in milk samples. Artichoke tissue, which has catalase activity, was immobilized with gelatine by means of glutaraldehyde and fixed on a pretreated teflon membrane. The electrode response was maximum when 0.05 M phosphate buffer was used at pH 7.0 and at 30 degrees C. Upon addition of hydrogen peroxide, the electrode gives a linear response in a concentration range of 5.0-50 x 10(-5) M with a response time of 3 min. The method was also applied to the determination of hydrogen peroxide in milk samples. 相似文献
29.
Telomere-specific fluorescence in situ hybridization analysis of couples with five or more recurrent miscarriages 总被引:1,自引:0,他引:1
Fluorescence in situ hybridization analysis using telomere specific probes has been used to detect cryptic translocations in the chromosomal telomeric regions. This study was performed in five clinically normal couples who have had five or more spontaneous abortions and whose karyotypes were found to be normal using conventional cytogenetic techniques. Using the telomere specific probes, in one couple we determined a cryptic translocation between chromosome 3 and 10, and, in another couple, the signal in chromosome 20 was detected in another chromosome, which was probably a D group chromosome. Additionally, in the latter and also in two other couples, we observed a polymorphism. The approach will be helpful for screening cryptic translocations using telomere specific multiple probe sets in couples with recurrent miscarriages. As prenatal diagnosis will be available for these couples for future pregnancies, it will be possible to help these families to have healthy fetuses. 相似文献
30.
Somatic mosaicism for a MECP2 mutation associated with classic Rett syndrome in a boy 总被引:4,自引:0,他引:4
Topçu M Akyerli C Sayi A Törüner GA Koçoğlu SR Cimbiş M Ozçelik T 《European journal of human genetics : EJHG》2002,10(1):77-81
Rett syndrome is a severe neurodevelopmental disorder that arises from mutations in the X-linked MECP2 gene. It is almost exclusively seen in girls due to the predominant occurrence of the mutations on the paternal X-chromosome, and also the early postnatal lethal effect of the disease causing mutations in hemizygous boys. We identified a boy with features of classic Rett syndrome who is mosaic for the truncating MECP2 mutation R270X. Chromosome analysis showed normal karyotype. These results indicate that a MECP2 mutation associated with Rett syndrome in females could lead to a similar phenotype in males as a result of somatic mosaicism. 相似文献