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111.
In many cases, particularly in retrospective studies, only formalin-fixed and paraffin-embedded (FFPE) tissue samples are
available for molecular studies. DNA recovered from FFPE tissues generally consists of fragmented small target sequences with
chemical alterations. Clonality analysis is not easy on FFPE samples, in fact, it requires even more experience than that
of performed on fresh samples or is more complicated than most genomic PCR amplifications for somatic genes. In our study,
we have performed a multi-parameter PCR evaluation investigating immunoglobulin heavy chain gene (IgH) and T-cell receptor
gamma gene (TCRy) rearrangements on non-purified crude lysates of FFPE samples, in order to establish the significance of
different variables on performance of PCR amplification. The results showed that a slight decrease in the concentration of
primers in combination with a slight increase in MgCl2 andTaq polymerase concentrations, as well as the use diluted crude template and a standard amount of dNTPs can be the modifications
of choice while adjusting IgH and TCRy clonality tests on poor quality DNA FFPE samples. Using our improved protocol, 74%
(17/23) of the tested B-cell lymphomas and 68% (31/46) of the tested T-cell lymphomas demonstrated monoclonal PCR product,
proving the applicability of our optimized method. Our experience may be of help during the optimization process in technically
difficult cases as well as to determine which parameters and how should be changed to minimize false-negative and false-positive
results.
Supported in part by the OTKA Research Fund (T046663 KON) and the Hungarian Academy of Sciences, Bolyai Janos Research Fellowship
(E.B.). 相似文献
112.
Drappier JC Mahé E Memin A Grossin M Descamps V Belaïch S Legrain S Crickx B 《Annales de dermatologie et de vénéréologie》2003,130(3):345-347
BACKGROUND: Prostatic adenocarcinoma is exceptionally associated with cutaneous lesions. We describe a patient with cutaneous lymphangitis and paraneoplastic ichtyosis related to prostatic cancer. CASE REPORT: A 92 year-old man had been treated for five years for a prostatic carcinoma. An angiomatous lesion developed with in 3 months near the right breast. Physical examination revealed axillary node enlargement, a large skin angiomatous lesion, and ichtyosis. The skin biopsy of the angiomatous skin lesion demonstrated its prostatic origin with carcinomatous metastases in the lymphatic vessels. The ichtyosis was considered as paraneoplastic. DISCUSSION: Cutaneous metastases from prostatic carcinoma are rare. Less than 1 p. 100 of cutaneous metastases are of prostate origin despite the high frequency of this cancer in the general population. The clinical aspects - angiomatous lesion and paraneoplastic ichtyosis - are exceptional. 相似文献
113.
We evaluated clinical presentation, cerebrospinal fluid (CSF), and magnetic resonance imaging (MRI) in patients with late-onset multiple sclerosis (LOMS). Fifty-two patients with definitive multiple sclerosis (MS) diagnosed after the age of 50 years were identified between 1991 and 2002. Data pertaining to clinical characteristics, CSF analysis, and cerebral and spinal MRI were compared with those of 52 young-onset MS (YOMS) patients matched for sex and disease duration. Mean age at the time of diagnosis was 57 years in the LOMS group - the oldest patient was 82 - and 29 years in the YOMS group. Motor symptoms were significantly more often present in the LOMS than in patients with YOMS (90 % vs. 67 %, p = 0.014). Visual symptoms, residual signs of optic neuritis, and dysarthria were less frequent for LOMS. Sensory symptoms, ataxia, oculomotor symptoms, cognitive disorder, or fatigue did not differ between both groups. The majority of LOMS patients (83 %) had a primary progressive disease course, whereas 94 % of the YOMS group had a relapsing-remitting course. MRI showed typical multifocal supratentorial (LOMS vs. YOMS: 96 % vs. 98 %) and infratentorial (44 % vs. 62 %) lesions without significant group differences. Of particular interest, spinal lesions were more common (81 %) in LOMS compared to YOMS (48 %, p = 0.024), and cerebellar lesions were less frequent in the LOMS group (11 % vs. 44 %, p = 0.001). Gadolinium-enhanced lesions were initially present in less LOMS patients (15 %) than in YOMS (63 %, p < 0.001). CSF analysis revealed pleocytosis less frequently in LOMS (34 %) compared to YOMS (67 %, p = 0.006) but oligoclonal banding occurred without in both groups without differences. YOMS patients responded to corticosteroids (93 %) to a significantly greater degree than LOMS patients (73 %; p = 0.004). For individuals who develop LOMS, a primary progressive course is frequent, with motor symptoms as the prominent feature. Vigilance is necessary to recognise MS in this population because of its unusual presentation. 相似文献
114.
In anaesthetized adult rats, facial nerve injury causes a disinhibition of the interhemispheric connections between homotopic representation fields in the primary motor cortex with a latency of 4 min (Toldi et al., 1996, Neurosci Lett. 203, 179-182). One possible explanation for the induction of such rapid changes is an alteration of the somatosensory input to the motor cortex. To test this hypothesis, unit activity in primary motor cortex was recorded during electrical stimulation of trigeminal afferents in the contralateral whisker-pad. About one-third of all recorded primary motor cortex neurons responded with latencies shorter than in the ventrolateral and posterior nuclei of the thalamus. Responses failed at stimulation frequencies > or = 10 Hz and after elimination or inactivation of the somatosensory cortex. Within primary motor cortex, the activatable neurons displayed a bilaminar distribution and were identified as pyramidal neurons by neurobiotin labelling. The results suggest that trigeminal afferents participate in modulation of the activity of primary motor cortex output neurons via primary somatosensory cortex-to-primary motor cortex associational connections, even under anaesthesia. 相似文献
115.
Talmadge JE Hood KC Zobel LC Shafer LR Coles M Toth B 《International immunopharmacology》2007,7(2):140-151
Selective inhibitors of cyclooxygenase-2 (COX-2) enzyme activity have shown chemopreventive activity in carcinogen-induced and transgenic rodent tumor models and clinically for colon cancer. However, the mechanism(s) by which COX-2 inhibitors reduce carcinogenesis remains controversial. We report herein that administration of the selective COX-2 inhibitor, celecoxib, significantly reduces the number of Gr1(+)CD11b(+) immature myeloid suppressor cells (IMSCs) during chemoprevention of 1,2-dimethylhydrazine diHCl-(1,2-DMH-) induction of large intestinal tumors in Swiss mice. Celecoxib administration also increased splenic lymphatic number and tumor infiltration by lymphocytes. The 1,2-DMH induction of large intestinal tumors was associated with a four-fold increase in IMSCs, and a decrease in splenic T cell number and function. Concordant with the changes in the IMSC frequency, messenger ribonucleic acid (mRNA) levels of inducible nitric oxide synthase (NOS-2) and arginase (Arg) were increased in the spleen of the tumor-bearing mice and normalized by celecoxib administration. In addition to delaying tumor induction, reducing tumor number, and increasing lymphocyte infiltration of tumors, celecoxib therapy reversed CD4(+) T cell loss, decreased IMSC numbers and increased mRNA levels of NOS-2 and Arg in the spleen. In summary, our results suggest that celecoxib chemoprevention of autochthonous intestinal tumors can regulate IMSCs and CD4(+) T cell numbers. 相似文献
116.
Davide Chiumello Sara Froio Bela?d Bouhemad Luigi Camporota Silvia Coppola 《Critical care (London, England)》2013,17(6):243
Over the past 30 years lung imaging has greatly contributed to the current understanding of the pathophysiology and the management of acute respiratory distress syndrome (ARDS). In the past few years, in addition to chest X-ray and lung computed tomography, newer functional lung imaging techniques, such as lung ultrasound, positron emission tomography, electrical impedance tomography and magnetic resonance, have been gaining a role as diagnostic tools to optimize lung assessment and ventilator management in ARDS patients. Here we provide an updated clinical review of lung imaging in ARDS over the past few years to offer an overview of the literature on the available imaging techniques from a clinical perspective. 相似文献
117.
Laszlo Denes Bela Szendex Julia Ember Jeno Major Laszlo Szporny Gyorgy Hajos Olga Nyeki Istvan Schon Karoly Lapis Lajos Kisfaludy 《Immunopharmacology and immunotoxicology》1987,9(1):1-18
The effects of seventeen synthetic analogs of thymopentin (TP-5) have been studied in the active and azathioprine-inhibited E-rosette tests.
Thymopentin was gradually shortened from the C terminus to peptides and single amino acids. Thymopoietin 32-34 (Arg-Lys-Asp-RGH-0205-TP-3) (II) and thymopoietin 32-35 (Arg-Lys-Asp-Val-RGH-0206-TP-4) (I) were the most active peptides.
Dipeptide Arg-Lys produced significant stimulatory effect on azathioprine (ED75) inhibited E-receptor. Treatment of azathioprine (ED75-inhibited E-rosette forming cells (ERFC) with arginine or especially lysine increased the number of ERFC.
Some of TP-4 analogs decreased further the number of ERFC decreased by azathioprine ED30. These “suppressive” peptides as well as TP-3 caused a partial arrest of K 562 cell proliferation up to 96 hours.
Results suggest that TP-5 is not the smallest active fragment of thymopoietins, since peptides (TP-3 and TP-4) exhibit similar or higher T-cell membrane activation on E-receptor. Arginine, lysine, and acidic aspartyl residue seem to be a necessary basic structure to produce a cumulative chemical signal on the activity of T-lymphocytes. 相似文献
Thymopentin was gradually shortened from the C terminus to peptides and single amino acids. Thymopoietin 32-34 (Arg-Lys-Asp-RGH-0205-TP-3) (II) and thymopoietin 32-35 (Arg-Lys-Asp-Val-RGH-0206-TP-4) (I) were the most active peptides.
Dipeptide Arg-Lys produced significant stimulatory effect on azathioprine (ED75) inhibited E-receptor. Treatment of azathioprine (ED75-inhibited E-rosette forming cells (ERFC) with arginine or especially lysine increased the number of ERFC.
Some of TP-4 analogs decreased further the number of ERFC decreased by azathioprine ED30. These “suppressive” peptides as well as TP-3 caused a partial arrest of K 562 cell proliferation up to 96 hours.
Results suggest that TP-5 is not the smallest active fragment of thymopoietins, since peptides (TP-3 and TP-4) exhibit similar or higher T-cell membrane activation on E-receptor. Arginine, lysine, and acidic aspartyl residue seem to be a necessary basic structure to produce a cumulative chemical signal on the activity of T-lymphocytes. 相似文献
118.
The echographic appearance of pelvic masses in children was examined in 38 patients. Sonography was correct in determining the site of origin in all cases. Cystic uterine masses and cystic ovarian masses were the most specific, representing hydrometrocolpos and benign ovarian cysts. A nonspecific sonographic pattern was encountered with complex masses, which proved to be ovarian teratomas, hemorrhagic ovarian cysts and pelvic abscesses. Although a number of characteristic features of teratomes have been described, these signs were seen very rarely in children. 相似文献
119.
Joel D Kopple Hu Ding Annamaria Letoha Bela Ivanyi David Pei-Yuan Qing Lázló Dux Hui-Yuan Wang Sandor Sonkodi 《Nephrology, dialysis, transplantation》2002,17(12):2122-2131
BACKGROUND: This study examined whether administration of L-carnitine ameliorates gentamicin-induced renal injury in rats. METHODS: Male Sprague-Dawley rats were assigned to one of seven treatment groups: group A (control) rats were given normal saline injections daily for 8 consecutive days; group B, C and D rats were given gentamicin injections, 50 mg/kg body weight/day daily for 8 consecutive days; and group E, F and G rats were given gentamicin injections, 80 mg/kg/day daily for 8 consecutive days. Starting 4 days before these injections, all groups were given additional injections, for 12 consecutive days, of normal saline (groups A, B and E) or L-carnitine at 40 mg/kg (groups C and F) or 200 mg/kg (groups D and G). Histological scoring of renal cortical pathology was performed after day 12. RESULTS: Among rats injected with gentamicin 50 mg/kg/day, those given either 40 or 200 mg/kg/day of L-carnitine had higher creatinine clearances at day 12 than the rats not given carnitine. In the rats given 80 mg/kg gentamicin and no carnitine, renal function tended to be lower than in controls. At day 12, the rats given gentamicin 80 mg/kg and L-carnitine 200 mg/kg/day, compared with rats given gentamicin 80 mg/kg and no carnitine, displayed lower serum urea and probably creatinine concentrations, and higher creatinine clearances, and their serum urea was not different from control (group A) rats. Both doses of gentamicin induced renal cortical histopathology. Changes were milder with gentamicin 50 mg/kg/day, and L-carnitine, particularly at 200 mg/kg/day, ameliorated the severity of renal pathology induced by both gentamicin doses. In rats given gentamicin 80 mg/kg/day, the animals treated with carnitine 200 mg/kg/day had significantly less severe proximal tubular necrosis and significantly greater mild proximal tubular necrosis compared with rats receiving L-carnitine 40 mg/kg/day or no carnitine. CONCLUSIONS: In rats receiving gentamicin, daily L-carnitine injections, particularly at 200 mg/kg/day, ameliorate the severity of renal cortical proximal tubular necrosis and maintain greater renal function. 相似文献
120.
Rectal endosonography in inflammatory bowel disease: differential diagnosis and prediction of remission 总被引:2,自引:0,他引:2
BACKGROUND AND STUDY AIMS: There are few and conflicting data on EUS features of the rectal wall in Crohn's disease (CD) and ulcerative colitis (UC). The aim of our study was to determine whether rectal EUS could first differentiate between CD and UC, and secondly predict remission in CD. PATIENTS AND METHODS: During a 14 month period we prospectively and blindly studied several parameters on rectal EUS (total wall thickness, mucosal appearance, submucosal thickness, number of enlarged vessels in the submucosa and number of pathological lymph nodes around the rectum and sigmoid colon) in 20 normal subjects, 26 patients with UC, 39 patients with CD, and four with infectious colitis. Comparisons were made between normal controls, patients with acute UC and those with acute CD, as well as between acute flare-ups and quiescent forms of CD and UC in the same patients. RESULTS: Normal subjects showed some features which were significantly different from those in CD or UC patients. A greater number of pathological lymph nodes was characteristic for acute UC, whereas the number of enlarged vessels was increased in acute CD. Quiescent CD showed a lower amount of wall thickening than acute CD. No significant alterations of the five parameters were found in quiescent UC compared to acute UC. CONCLUSIONS: This study suggests that EUS could be helpful in differentiating acute UC from CD, and to predict remission in CD. 相似文献