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51.
52.
Pavlopoulos E Kokkinaki M Koutelou E Mitsiadis TA Prinos P Delidakis C Kilpatrick MW Tsipouras P Moschonas NK 《Biochimica et biophysica acta》2002,1574(3):375-382
The Drosophila neuralized (neur) gene belongs to the neurogenic group of genes involved in regulating cell-cell interactions required for neural precursor development. neur mutant phenotypes include strong overcommitment to neural fates at the expense of epidermal fates. The human neuralized homolog (NEURL) has been recently determined and found to map to chromosome 10q25.1 within the region frequently deleted in malignant astrocytomas. Because of its potential importance in developmental processes, we analyzed the structure of the mouse homolog, Neurl, and its expression pattern in embryonic tissues. Neurl activity is detected from early developmental stages in several tissues and organs including neural tissues, limbs, the skeletal system, sense organs and internal organs undergoing epithelial-mesenchymal interactions. Neurl encodes a polypeptide associated with the plasma membrane but also detected in the cytoplasm. Similarly to the Drosophila gene, mammalian neuralized may code for an important regulatory factor. 相似文献
53.
Mannan-binding lectin: clinical significance and applications 总被引:32,自引:0,他引:32
Kilpatrick DC 《Biochimica et biophysica acta》2002,1572(2-3):401-413
Mannan-binding lectin (MBL) is a collectin (protein with both collagen-like and C-type lectin domains) synthesised in the liver and secreted into the bloodstream. Its plasma concentration is for the most part genetically determined by a series of allelic dimorphisms located both in the structural gene and in the promoter region. Genotypes made up of combinations of seven haplotypes are mainly responsible for a 1000-fold concentration variation found in human beings. MBL is a pattern recognition molecule able to bind repeating sugar arrays on many microbial surfaces, and can activate complement via associated serine proteases. A poorly defined proportion (roughly 10%) of the population with the lowest MBL concentrations is thought to be MBL insufficient and more vulnerable to a variety of infectious and noninfectious disorders. The evidence that MBL makes an important contribution to innate immunity, by increasing susceptibility to disease and/or affecting the course of disease, is discussed in detail. Preliminary results from MBL replacement therapy are encouraging, and extension of this approach to large-scale randomised clinical trials would provide solid evidence concerning the physiological significance of this protein. 相似文献
54.
Most arterial mechanics studies have focused on excised non-coronary vessels, with few studies validating the application of ex-vivo results to in-vivo conditions. A method was developed for testing the mechanical properties of intact left anterior descending coronary arteries under a variety of conditions. Vascular deformation and pressure were simultaneously measured with intravascular ultrasound and a pressure transducer guidewire, respectively. Results suggest the importance of understanding in-vivo factors such as myocardial support, vascular tone and local pressure fluctuations when applying ex-vivo coronary characterization data. With further development, this method can more accurately characterize the true in-vivo constitutive behavior in normal and atherosclerotic coronaries. 相似文献
55.
Cytoplasmic expression of a soluble synthetic mammalian metallothionein-α domain in Escherichia coli 总被引:1,自引:0,他引:1
Bacteria are commonly used for bioremediation of heavy metal pollution and strategies to improve their performance in this
respect are desirable. In this study, an Escherichia coli strain was engineered to express a common metallothionein-α domain. The metallothionein-α domain was over-expressed in the
cytoplasm of E. coli as a fusion to the carboxyl terminal of maltose binding protein. The fusion protein was highly soluble in the cytoplasm of
E. coli. When grown in the presence of cadmium, cells expressing the metallothionein-α fusion protein showed increased viability
compared with control cells. Cells expressing the metallothionein-α also demonstrated increased accumulation of cadmium. 相似文献
56.
Kilpatrick LE Song YH Rossi MW Korchak HM 《American journal of physiology. Cell physiology》2000,279(6):C2011-C2018
Tumor necrosis factor-(TNF-) triggers degranulation and oxygen radical release in adherentneutrophils. The p60TNF receptor (p60TNFR) is responsible forproinflammatory signaling, and protein kinase C (PKC) is a candidatefor the regulation of p60TNFR. Both TNF- and the PKC-activatorphorbol 12-myristate 13-acetate triggered phosphorylation of p60TNFR.Receptor phosphorylation was on both serine and threonine but not ontyrosine residues. The PKC- isotype is a candidate enzyme for serinephosphorylation of p60TNFR. Staurosporine and the PKC- inhibitorrottlerin inhibited TNF--triggered serine but not threoninephosphorylation. Serine phosphorylation was associated withreceptor desensitization, as inhibition of PKC resulted in enhanceddegranulation (elastase release). After neutrophil activation, PKC-was the only PKC isotype that associated with p60TNFR within thecorrect time frame for receptor phosphorylation. In vitro, onlyPKC-, but not the -, I-, II-, or -isotypes, wascompetent to phosphorylate the receptor, indicating that p60TNFR is adirect substrate for PKC-. These findings suggest a selective rolefor PKC- in negative regulation of the p60TNFR and ofTNF--induced signaling. 相似文献
57.
58.
Derivative emission spectrofluorimetry: Application to the analysis of newly approved FDA combination of ibuprofen and famotidine in tablets
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A new combination of ibuprofen (NSAID) and famotidine (H2 receptor antagonist) was recently approved by the FDA. It was formulated to relief pain while decreasing the risk of ulceration, which is a common problem for patients receiving NSAID. A rapid and simple derivative emission spectrofluorimetric method is proposed for the simultaneous analysis of this combination in their pharmaceutical preparation. The method is based upon measurement of the native fluorescence intensity of the two drugs at λex = 233 nm in acetonitrile. The emission data were differentiated using the first (D1) derivative technique. The plots of derivative fluorescence intensity versus concentration were rectilinear over a range of 2–35 and 0.4–8 µg/mL for both ibuprofen (IBU) and famotidine (FAM), respectively. The method was sensitive as the limits of detection were 0.51 and 0.12 µg/mL and limits of quantitation were 1.70 and 0.39 µg/mL, for IBU and FAM respectively. The proposed derivative emission spectrofluorimetric method was successfully applied for the determination of the two drugs in their synthetic mixtures and tablets with good accuracy and precision. The proposed method was validated as per ICH guidelines. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
59.
Ahmed Fahal EL Sheikh Mahgoub Ahmed M. EL Hassan Manar Elsheikh Abdel-Rahman 《PLoS neglected tropical diseases》2015,9(3)
This communication reports on the Mycetoma Research Centre of the University of Khartoum, Sudan experience on 6,792 patients seen during the period 1991–2014.The patients were predominately young (64% under 30 years old) males (76%). The majority (68%) were from the Sudan mycetoma belt and 28% were students. Madurella mycetomatis eumycetoma was the most common type (70%). In 66% of the patients the duration of the disease was less than five years, and 81% gave a history of sinuses discharging mostly black grains (78%). History of trauma at the mycetoma site was reported in 20%. Local pain was reported in 27% of the patients, and only 12% had a family history of mycetoma. The study showed that 57% of the patients had previous surgical excisions and recurrence, and only 4% received previous medical treatment for mycetoma. Other concomitant medical diseases were reported in 4% of the patients. The foot (76%) and hand (8%) were the most commonly affected sites. Less frequently affected sites were the leg and knee (7%), thigh (2%), buttock (2%) and arm and forearm (1%). Rare sites included the chest wall, head and neck, back, abdominal wall, perineum, oral cavity, tongue and eye. Multiple sites mycetoma was recorded in 135 (2%) of cases. At presentation, 37% of patients had massive lesions, 79% had sinuses, 8% had local hyper-hydrosis at the mycetoma lesion, 11% had regional lymphadenopathy, while 6% had dilated tortuous veins proximal to the mycetoma lesions. The diagnosis of mycetoma was established by combined imaging techniques and cytological, histopathological, serological tests and grain culture. Patients with actinomycetoma received a combination of antimicrobial agents, while eumycetoma patients received antifungal agents combined with various surgical excisions. Surgical excisions in the form of wide local excision, debridement or amputation were done in 807 patients, and of them 248 patients (30.7%) had postoperative recurrence. Different types of amputations were done in 120 patients (1.7%). 相似文献
60.
Ahmed Fahal EL Sheikh Mahgoub Ahmed Mohamed EL Hassan Angom Osman Jacoub Doaa Hassan 《PLoS neglected tropical diseases》2015,9(3)
Mycetoma is a unique neglected tropical disease which is endemic in what is known as the “mycetoma belt”. The disease has many devastating impacts on patients and communities in endemic area and is characterised by massive deformity, destruction and disability. Mycetoma is commonly seen in the foot and hand and less frequent in other parts of the body. Mycetoma of the head and neck is a rarity and is associated with high morbidity and even mortality if not treated early. In this communication we report on 49 patients with head and neck mycetoma followed up at the Mycetoma Research Centre in Khartoum. Most of the reported patients had actinomycetoma and the majority were young adult males from mycetoma endemic areas in the Sudan. Most of them were students, farmers and workers. Prior to presentation the majority had long disease duration and the cause was multifactorial. Advanced disease with massive lesion, deformity and disability was the common presentation. There was no obvious history of local trauma, familial tendency or other predisposing factor identified in this group of patients. MRI and CT scan were the most accurate diagnostic tools to determine the disease extent. The treatment outcome was rather poor and characterised by low cure rate, poor outcome and high follows-up dropout. Such a gloomy outcome calls for structured and objective health education programs. 相似文献