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41.
Fluorometric quantification of biological molecules is a key feature used in many biosensing studies. Fluorescence resonance energy transfer (FRET) using highly fluorescent quantum dots offers highly sensitive detection of the in-proximity wide variety of analyst molecules. In this contribution, we report the use of carbon quantum dots (CDs) for the ultrasensitive optical biosensing of cancer antigen 125 (CA-125) in the early malignant stage. This approach is based on monitoring the quenching of CDs luminescence at 535 nm by CA-125 after excitation at 425 nm and pH 10. The calibration of this method was performed in the concentration range of CA-125 from 0.01 to 129 U ml−1 (R2 = 0.99) with a detection limit of 0.66 U ml−1, which matches remarkably with the standard chemiluminometric method in control and real patient samples. The sensing mechanism for cancer antigen 125 assessment was discussed on the basis of fluorescence quenching of CDs and time-resolved photoluminescence spectroscopy. The current method is easy, sensitive, cost-effective and provides a wide range of validity, which helps in overcoming the limitations of high cost and time consumption exhibited by many other traditional clinical assays for CA-125 quantification.

Fluorometric quantification of biological molecules is a key feature used in many biosensing studies.  相似文献   
42.
There is a gap in research about the differences in smile attractiveness. The problem the study addresses is how the vertical canine and incisor position affect smile attractiveness. The aim of this study was to assess the perception of the smile attractiveness between Saudi laypersons, orthodontists, non-orthodontist, and various dental students levels, and to determine how the canine and incisor vertical positions affect the attractiveness of smile. The study is a cross-sectional survey and was conducted at King Abdulaziz University, Jeddah, Saudi Arabia. Six groups of subjects participated in the study: Orthodontic residents (n = 31), prosthodontic, restorative, periodontics specialties residents specialties residents (n = 30), interns (n = 31), fifth year students (n = 41), 6th year students (n = 39), and laypeople (n = 39). Participants were asked to rate the attractiveness of a smile of a female subject photographed using a Minolta DiMage 7i digital camera. The image had been manipulated to produce 2 sets of images; 1 to modify the incisors and 1 to change the canines. The subjects were asked to choose the most and least attractive picture. For the best incisor positions, only the laypeople and prosthodontics liked the original picture, the rest liked +0.5 mm which accentuate the smile curve and make it follow the lower lip line. For the worst incisor position, all groups did not prefer the minus 1.5 reversed smile. For the best canine vertical position, all groups preferred the original position where canine was at the level of the incisal plane. For the worst canine position, they all disliked the minus 1.5 reversed smile. Results confirmed past findings that orthodontists are in general more critical about smile attractiveness than laypersons, but just like other dental specialists. The findings can be used in the esthetic dentistry field, but further research on the study population based on other dental design parameters remain necessary.  相似文献   
43.
Work climate is indicative of how well the organization is realizing its full potential. An accurate assessment of work climate can identify the unnecessary obstacles to nurses interfering with their best performance. The present study aims to assess nurses' work climate at Alexandria Main University Hospital. The study sample included all nurses (N=400) who were working in inpatient medical and surgical units at the Alexandria Main University Hospital who were available at the time of data collection. A structured questionnaire was developed to assess nurses' perceptions regarding the dimensions of work climate. Data was collected by individual interview using the structured questionnaire. Results indicated that the highest percentages of nurses in medical and surgical units perceived that their work climate is characterized by good way of performance management, feeling of responsibility, warmth and supportive relationships, quality of communication, morale, organizational clarity and feeling of identity and belongness to the hospital. Nurses perceived that they are lacking work climate conducive to conflict resolution, participation in decision making, opportunity for training and development, fair rewards and recognition, calculated risks, sufficient resources, effective leadership and teamwork. There were no significant difference between nurses perceptions in medical and surgical units regarding all dimensions of work climate. The highest percentage of nurses in all units were satisfied only with the feeling of responsibility, way of performance management, and quality of communication. Conflict and identity were perceived as the most important areas that need improvement in the hospital. Based on the results recommendations were given to enhance work climate through designing compensation and recognition systems, and negotiate their requirements and accomplishment based on established standards and outcomes measures. Also, encouragement of and planning for participative decision making, teamwork, in-service training program and open communication are recommended to be present in the work units.  相似文献   
44.
Goodpasture's disease is a severe nephritis characterized by autoantibodies to the alpha3 chain of type IV collagen, alpha3(IV)NC1, in the glomerular basement membrane. The disease is very strongly associated with HLA-DR15, the affinities of alpha3(IV)NC1 peptides for DR15 are known, and elution experiments have identified major naturally processed sequences. Here, the fine specificity and cytokine profile of alpha3(IV)NC1-reactive T cells from patients with Goodpasture's disease is defined. Peripheral blood mononuclear cells from patients at diagnosis proliferated in response to significantly more peptides (chi(2) = 8.6, P = 0.004) from a panel spanning the sequence of alpha3(IV)NC1 than did those from control DR15-positive donors and were highly focused (P = 0.0002, binomial distribution) on two peptides, alpha3(71-90) and alpha3(131-150). Some peptides induced interferon-gamma, but none induced IL-4. Resolution of disease was accompanied by a striking deviation of the responses from proliferation to secretion of the T-regulatory cytokine IL-10, and addition of neutralizing antibody confirmed that such IL-10 production was suppressive. The affinity of the peptides for DR15 molecules was positively correlated (chi(2) = 14.6, P = 0.00067) with the ability to elicit proliferation. However, unlike foreign antigens, this hierarchy is not due to responses against the major naturally processed peptides, which rarely stimulated proliferation and which have only intermediate affinity for DR15 molecules. It is inferred that the helper response to alpha3(IV)NC1 in Goodpasture's disease is dominated by epitopes that are normally inefficiently presented because of processing constraints.  相似文献   
45.
Natamycin (NT) is a synthetic broad-spectrum antifungal used in eye drops. However, it has low solubility and high molecular weight, limiting its permeation, and generally causes eye discomfort or irritation when administered. Therefore, the present study aimed to develop an ophthalmic in situ gel formulation with NT-loaded cubosomes to enhance ocular permeation, improve antifungal activity, and prolong the retention time within the eye. The NT-loaded cubosome (NT-Cub) formula was first optimized using an I-optimal design utilizing phytantriol, PolyMulse, and NT as the independent formulation factors and particle size, entrapment efficiency %, and inhibition zone as responses. Phytantriol was found to increase particle size and entrapment efficiency %. Higher levels of PolyMulse slightly increased the inhibition zone whereas a decrease in particle size and EE% was observed. Increasing the NT level initially increased the entrapment efficiency % and inhibition zone. The optimized NT-Cub formulation was converted into an in situ gel system using 1.5% Carbopol 934. The optimum formula showed a pH-sensitive increase in viscosity, favoring prolonged retention in the eye. The in vitro release of NT was found to be 71 ± 4% in simulated tear fluid. The optimum formulation enhanced the ex vivo permeation of NT by 3.3 times compared to a commercial formulation and 5.2 times compared to the NT suspension. The in vivo ocular irritation test proved that the optimum formulation is less irritating than a commercial formulation of NT. This further implies that the developed formulation produces less ocular irritation and can reduce the required frequency of administration.  相似文献   
46.
Hydatid cyst (cystic echinococcosis) is a chronic parasitic infection by the larval stage of the cestode that is called Echinococcus granulosus (E. granulosus) resulting in the development of cystic lesions in animals and humans. In this report, we describe a rare phenotype of hydatid cyst in the breast of a 23-year-old female presented with breast mass in the left upper outer quadrant for 3 months with palpable left axillary lymph nodes. Both US and mammography provided a picture of complex suspicious cystosolid lesion with amorphous micro-calcification (BIRAD-4A). Surgical consultation was performed and Tru-Cut biopsy was recommended. Histopathology results revealed multiple viable protoscolices of E. granulosus and suggested the final diagnosis of breast hydatid cyst. The patient returned with ruptured and infected hydatid cyst of the breast and started treatment with Albendazole 400 mg twice daily in addition to antibiotics. Following-up after two months of Albendazole treatment showed a dramatic shrinkage in the size of the cystic lesion. In conclusion, hydatid cyst should be considered as a differential diagnosis of any cystic or cystosolid lesion in the breast and any organ in the body from head to toe apart from the hair and nails. Radiologists should be aware to the benign lesions that may mimic breast cancer to avoid misdiagnosis and unnecessary invasive procedures and consequent complications.  相似文献   
47.
48.
Neuroinflammation and iron accumulation are hallmarks of a variety of adult neurodegenerative diseases. In Sanfilippo syndrome (mucopolysaccharidosis type III, MPSIII, a pediatric neurodegenerative disease that shares some features with adult neurodegenerative diseases), the progressive accumulation of heparan sulfate oligosaccharides (HSOs) induces microglia and astrocytes to produce pro‐inflammatory cytokines leading to severe neuroinflammation. The objectives of the present study were (1) to measure the local iron concentration and to assess iron metabolism in the brain of a MPSIIIB murine model and (2) to identify the brain cells involved in this accumulation. We found that iron accumulation in MPSIIIB mice primarily affected the cerebral cortex where hepcidin levels were higher than in wild‐type mice, and increased with aging. This increase was correlated with low expression of ferroportin 1 (FPN1), and thus brain iron retention. Moreover, we showed in vitro that HSOs are directly responsible for the production of hepcidin and the relative decrease in FPN1 expression when added to cultures of microglia and, to a lesser extent, to cultures of astrocytes. In contrast, no significant differences were observed in neurons. Hepcidin induction results from activation of the TLR4 pathway and STAT3 signaling, and leads to iron retention within microglia. Our results show that microglia have a key role in cerebral hepcidin overexpression and thus in the brain iron accumulation observed in the MPSIIIB model.  相似文献   
49.
BACKGROUND Proton pump inhibitors are often used to prevent gastro-intestinal lesions induced by nonsteroidal anti-inflammatory drugs. However, they are not always effective against both gastric and duodenal lesions and their use is not devoid of side effects.AIM To explore the mechanisms mediating the clinical efficacy of STW 5 in gastroduodenal lesions induced by nonsteroidal anti-inflammatory drugs(NSAIDs),exemplified here by diclofenac, in a comparison to omeprazole.METHODS Gastro-duodenal lesions were induced in rats by oral administration of diclofenac(5 mg/kg) for 6 successive days. One group was given concurrently STW 5(5 mL/kg) while another was given omeprazole(20 mg/kg). A day later, animals were sacrificed, stomach and duodenum excised and divided into 2 segments:One for histological examination and one for measuring inflammatory mediators(tumor necrosis factor α, interleukins-1β and 10), oxidative stress enzyme(heme oxygenase-1) and apoptosis regulator(B-cell lymphoma 2).RESULTS Diclofenac caused overt histological damage in both tissues, associated with parallel changes in all parameters measured. STW 5 and omeprazole effectively prevented these changes, but STW 5 superseded omeprazole in protecting against histological damage, particularly in the duodenum.CONCLUSION The findings support the therapeutic usefulness of STW 5 and its superiority over omeprazole as adjuvant therapy to NSAIDs to protect against their possible gastro-duodenal side effects.  相似文献   
50.

Purpose

The aim of this study was to highlight the different computed tomography (CT) features of groove pancreatitis (GP) in order to make this entity more familiar to radiologist.

Patients & method

This study enrolled 15 patients who had histopathologically confirmed GP. Their CT scans were retrospectively reviewed for the encountered manifestations.

Results

Pure & segmental forms were identified retrospectively in 6 & 9 patients. The most frequent findings noted in patients' scans were the following, in descending order: medial duodenal wall thickening & cysts, duodenal luminal narrowing, regional lymphadenopathies, pancreatic involvement, isolated groove affection, pancreatic calcifications, distal CBD narrowing, pancreatic duct abnormalities, and retro-peritoneal stranding.

Conclusion

Although the CT features of GP mimic other peripancreatic tumors, yet the constantly associated findings in the proven cases of GP in our study were: duodenal wall thickening, cysts formation, and luminal narrowing. So the presence of these features in alcoholic middle aged male patient with groove or pancreatic lesion, have to trigger radiologist's dubiety of GP entity and so to be addressed in his opinion. Nevertheless, GP diagnosis is still challenging & should be considered based on clinical & radiological data in conjunction with the laboratory and pathological results.  相似文献   
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