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51.
Fine-needle aspiration (FNA) cytology and immunophenotyping by flow cytometry (FCM) are increasingly being used for diagnosing and subclassifying lymphoma in the REAL/WHO classification. Herein, we report a case of primary mediastinal large B-cell lymphoma (PMBL), a subtype of diffuse large B-cell lymphoma in the WHO classification, diagnosed by FNA cytology in conjunction with FCM. This, to our knowledge, has not previously been reported. A 57-yr-old woman presented with bilateral axillary lymphadenopathy and intermittent shortness of breath. CT scan revealed a 5-cm anterior mediastinal mass and mediastinal lymphadenopathy. Endoscopic ultrasound-guided FNA of a 4.5-cm subcarinal lymph node showed medium to large atypical lymphocytes with scant to moderate finely vacuolated cytoplasm. Nuclei were enlarged, cleaved, noncleaved, lobulated, and hyperchromatic. The background showed lymphoglandular bodies. Malignant large cell lymphoma was cytologically diagnosed. FCM, performed on a portion of the FNA specimen, demonstrated large B cells devoid of surface immunoglobulin expression, the characteristic immunophenotype of PMBL. The histologic diagnosis was PMBL. Touch-imprint cytology of the histologic specimen showed large cells with a narrow rim of clear cytoplasm and prominent outer cell border. Nuclear features were similar to the FNA specimen. In the presence of a mediastinal mass, FNA cytology in conjunction with FCM can effectively diagnose PMBL in the appropriate clinical setting.  相似文献   
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Annals of Biomedical Engineering - Predicting potential complications after aortic valve replacement (AVR) is a crucial task that would help pre-planning procedures. The goal of this work is to...  相似文献   
53.
MIC end points for the most commonly prescribed azole antifungal drug, fluconazole, can be difficult to determine because its fungistatic nature can lead to excessive "trailing" of growth during susceptibility testing by National Committee for Clinical Laboratory Standards broth macrodilution and microdilution methods. To overcome this ambiguity, and because fluconazole acts by inhibiting ergosterol biosynthesis, we developed a novel method to differentiate fluconazole-susceptible from fluconazole-resistant isolates by quantitating ergosterol production in cells grown in 0, 1, 4, 16, or 64 microg of fluconazole per ml. Ergosterol was isolated from whole yeast cells by saponification, followed by extraction of nonsaponifiable lipids with heptane. Ergosterol was identified by its unique spectrophotometric absorbance profile between 240 and 300 nm. We used this sterol quantitation method (SQM) to test 38 isolates with broth microdilution end points of /=64 microg/ml (resistant) and 10 isolates with trailing end points by the broth microdilution method. No significant differences in mean ergosterol content were observed between any of the isolates grown in the absence of fluconazole. However, 18 susceptible isolates showed a mean reduction in ergosterol content of 72% after exposure to 1 microg of fluconazole/ml, an 84% reduction after exposure to 4 microg/ml, and 95 and 100% reductions after exposure to 16 and 64 microg of fluconazole/ml, respectively. Ten SDD isolates showed mean ergosterol reductions of 38, 57, 73, and 99% after exposure to 1, 4, 16, and 64 microg of fluconazole/ml, respectively. In contrast, 10 resistant isolates showed mean reductions in ergosterol content of only 25, 38, 53, and 84% after exposure to the same concentrations of fluconazole. The MIC of fluconazole, by using the SQM, was defined as the lowest concentration of the drug which resulted in 80% or greater inhibition of overall mean ergosterol biosynthesis compared to that in the drug-free control. Of 38 isolates which gave clear end points by the broth microdilution method, the SQM MIC was within 2 dilutions of the broth microdilution MIC for 33 (87%). The SQM also discriminated between resistant and highly resistant isolates and was particularly useful for discerning the fluconazole susceptibilities of 10 additional isolates which gave equivocal end points by the broth microdilution method due to trailing growth. In contrast to the broth microdilution method, the SQM determined trailing isolates to be susceptible rather than resistant, indicating that the SQM may predict clinical outcome more accurately. The SQM may provide a means to enhance current methods of fluconazole susceptibility testing and may provide a better correlation of in vitro with in vivo results, particularly for isolates with trailing end points.  相似文献   
54.
ObjectiveAdipokines are signaling and mediator proteins secreted from adipose tissue. A novel adipokine, visfatin, was reported as a protein which was mainly expressed in visceral adipose tissue. Controversial results have been shown regarding the changes of adipokines following weight reduction. So we investigated the effects of weight reduction on serum concentrations of adiponectin and visfatin in morbidly obese subjects.Methods35 severely obese patients (26 females and 9 males), aged 15-58 years, were studied. Anthropometric parameters and biochemical parameters as well as adiponectin and visfatin were analyzed before and 6 weeks after weight reduction.ResultsAnthropometric indices decreased significantly. Blood levels of low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglyceride were reduced significantly. The reduction of visfatin and the elevation of adiponectin were significant as well. However, other parameters like fasting glucose and insulin did not change. Moreover, we could not find any significant correlation between the change of serum visfatin and that of adiponectin. Conclusions: 6-week weight reduction after bariatric surgery resulted in decreased serum visfatin and increased adiponectin levels. However, we cannot find any significant correlation between changes of adiponectin, visfatin, BMI, waist circumference, and insulin resistance. Further studies with different design are suggested to clarify these associations.Key Words: Adiponectin, Visfatin, Morbid obesity, Bariatric surgery, Weight loss  相似文献   
55.
Phenotyping is commonly used for detection of extended-spectrum beta-lactamase (ESBL) production in gram-negative isolates. ESBLs are mainly coded for by four important genes, namely bla (TEM), bla (SHV), bla (CTX-M), and bla (OXA). Our aim in this study is to assess use of a multiplex PCR as a rapid method to identify four common genes responsible for ESBL production in different gram-negative isolates. All 793 clinical isolates are subjected to both screen and confirmatory testing for ESBL production using double disc synergy testing (DDST). Two hundred isolates with the ESBL phenotype are subjected to multiplex PCR for detection of the four genes bla (TEM, SHV, CTX-M, and OXA). The isolates were obtained from various clinical specimens: 68 (34 %) were isolated from urine cultures, 43 (21.5 %) from sputum, 26 (13 %) from wounds, 34 (17 %) from blood culture, 20 (10 %) from stool of healthy carrier and nine (4.5 %) from bronchoalveolar lavages. In this study, 83 isolates (41.5 %) were from outpatients (urine and stool specimens only), and the remaining 117 isolates (58.5) were from inpatients. By PCR technique, 181 isolates were found to be ESBL producers. blaTEM was the commonest genotype (39.2 %), followed by blaSHV (32.5 %) and blaCTX-M (30.9 %), either alone or in combination. Acinetobacter baumannii isolate had none of the ESBL genes. Eighteen (9.9 %) out of 181 isolates carried more than one type of beta-lactamase genes. Our study demonstrated rapid detection of bla (TEM, SHV, CTX-M, and OXA) in isolates belonging to Enterobacteriaceae and other nonfermenting clinical isolates using multiplex PCR. This genotypic method provided a rapid and efficient differentiation of ESBLs in the laboratory.  相似文献   
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Physical and hormonal profile of male sexual development in epilepsy   总被引:3,自引:2,他引:1  
PURPOSE: This study was designed to investigate the effect of epilepsy and antiepileptic drugs (AEDs) on both the physical and hormonal aspects of the sexual development of male patients with epilepsy. METHODS: One hundred thirty male subjects with epilepsy, their age ranging between 8 and 18 years (mean, 14 +/- 2.9 years), entered the study; all were taking AEDs. Anthropometric measurements [height, weight, and body mass index (BMI)], testicular volume, penile length, and pubarche were assessed in the studied groups, as well as measurement of the levels of testosterone (T), free testosterone (FT), estradiol (E2), lutenizing hormone (LH), follicle-stimulating hormone (FSH), and prolactin (PRL), and the results were compared with those of a control group. RESULTS: In this study, male patients older than 16 years were significantly shorter than their matched controls. The mean values of testicular volume and penile length were significantly lower in the patients in the different age subgroups, and the pubic hair staging (pubarche) was delayed in the patients older than 16 years. The mean values of total testosterone, estradiol, LH, and FSH serum levels were significantly higher, whereas the mean values of free testosterone, total-T/E2, total. T/LH, and FT/E2 ratios were lower in the patient subgroups compared with their age-matched controls. There were no significant changes in the mean basal PRL serum levels in the patients compared with the controls. The present study demonstrated a reduction in the testicular volume and penile length, significantly lower mean values of free testosterone and total-T/E2, and a higher mean value of E2 in the patients receiving polytherapy in the age subgroup older than 16 years compared with those on monotherapy; however, there was no demonstrable effect of seizure control or the duration of illness in any of the studied parameters. CONCLUSIONS: There is a delay in the sexual development of male patients with epilepsy in the different age subgroups, with endocrine changes in the form of increase in the total testosterone, but the free testosterone is lower, and an increase in estradiol, with lower T/LH levels. Patients receiving polytherapy, especially those older than 16 years, were more likely to have delayed gonadarch and disturbances in their hormonal profile.  相似文献   
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60.
Background: The present study was performed to investigate the effect of neonatal hypoxic–ischemic encephalopathy (HIE) on the neurotransmitter neurokinin A (NKA) and determine its relation to the severity of neonatal hypoxia. Methods: Eighteen neonates suffering from HIE were compared to 10 clinically healthy full‐term neonates acting as the control group. Maternal history of each neonate was collected, then deliveries were attended, resuscitation details including the Apgar score and thorough clinical examination of the neonates were performed. Routine laboratory work‐up was done for the enrolled neonates, including complete blood count and C‐reactive protein as well as estimation of NKA by enzyme‐linked immunosorbent assay in the cord blood and after clinical stabilization. Results: NKA was significantly lower in HIE patients compared to the controls at delivery with improvement in the follow‐up sample. Additionally, the maximum decrease was detected in the neonates who suffered severe hypoxia compared to those who suffered mild hypoxia. Significant positive correlations were demonstrated between NKA at birth and Apgar scores at the 10th and 15th min. Regression showed that stage of HIE was the strongest determinant factor for the level of NKA at birth. Conclusion: NKA levels are decreased in HIE and this is more profound in the severe degrees of hypoxia compared to the mild ones. This emphasizes its role in pathogenesis of HIE and further proves that an imbalance in the central neuropeptide system results from HIE in the neonatal period.  相似文献   
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