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1.
The purpose of this study was to design a synthetic nanofibrillar matrix that more accurately models the porosity and fibrillar geometry of cell attachment surfaces in tissues. The synthetic nanofibrillar matrices are composed of nanofibers prepared by electrospinning a polymer solution of polyamide onto glass coverslips. Scanning electron and atomic force microscopy showed that the nanofibers were organized into fibrillar networks reminiscent of the architecture of basement membrane, a structurally compact form of the extracellular matrix (ECM). NIH 3T3 fibroblasts and normal rat kidney (NRK) cells, when grown on nanofibers in the presence of serum, displayed the morphology and characteristics of their counterparts in vivo. Breast epithelial cells underwent morphogenesis to form multicellular spheroids containing lumens. Hence the synthetic nanofibrillar matrix described herein provides a physically and chemically stable three-dimensional surface for ex vivo growth of cells. Nanofiber-based synthetic matrices could have considerable value for applications in tissue engineering, cell-based therapies, and studies of cell/tissue function and pathology.  相似文献   
2.
BACKGROUND AND PURPOSE: Single agent mitomycin c (MMC) has been shown to improve the outcome of radiotherapy in single institution trials. In order to confirm these findings in a broader worldwide setting, the International Atomic Energy Agency (IAEA) initiated a multicentre trial randomising between radiotherapy alone versus radiotherapy plus MMC. MATERIAL AND METHODS: Patients with advanced head and neck cancer were treated with primary curative radiotherapy (66 Gy in 33 fractions with five fractions per week) +/-a single injection (15 mg/m(2)) of MMC at the end of the first week of radiotherapy. Stratification parameters were tumour localization, T-stage, N-stage, and institution. A total of 558 patients were recruited in the trial from February 1996 to December 1999. Insufficient accrual and reporting led to the exclusion of three centres. The final study population consisted of 478 patients from seven centres. Patients had stage III (n=223) or stage IV (n=255) squamous cell carcinoma of the oral cavity (n=230), oropharynx (n=140), hypopharynx (n=65) or larynx (n=43). Prognostic factors like age, gender, site, size, differentiation and stage were well balanced between the two arms. RESULTS: The haematological side effects of MMC were very modest (<5% grade 3-4) and did not require any specific interventions. Furthermore, MMC did not enhance the incidence or severity of acute and late radiation side effects. Confluent mucositis and dry skin desquamation was common, occurring in 56% and 62% of patients, respectively. The overall 3-year primary locoregional tumour control, disease-specific and overall survival rates were 19, 36 and 30%, respectively. Gender, haemoglobin drop, tumour site, tumour and nodal stage were significant parameters for loco-regional tumour control. There was no significant effect of MMC on locoregional control or survival, except for the 161 N0 patients, where MMC resulted in a better loco-regional control (3-year estimate 16% vs. 29%, P=0.01). CONCLUSIONS: The study did not show any major influence of MMC on loco-regional tumour control, survival or morbidity after primary radiotherapy in stage III-IV head and neck cancer except in N0 patients where loco-regional control was significantly improved.  相似文献   
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4.
Neurological melioidosis is a very rare and very few cases have been reported from India. Presentation is an extremely varied and as this disease is associated with high mortality, high index of suspicion is needed to diagnose and treat. In this context, we report a patient presenting as Guillain Barre syndrome evaluated as melioidosis.Key Words: Guillain Barre’ syndrome, infection, melioidosis  相似文献   
5.

Background:

Data is scarce on prevalence of extracranial carotid atherosclerosis (ECA) in strokes <50 years and its association with lifestyle factors.

Objective:

Study role of (a) ECA in non-cardio-embolic anterior circulation young strokes, and (b) smoking and alcohol in ECA.

Materials and Methods:

Cardiovascular risk factors and evidence of ECA on carotid doppler ultrasound (CDUS) was evaluated in an one-year preliminary cross-sectional study of consecutive strokes between 20 years and 49 years. Females were excluded.

Results:

There were 46 male strokes (mean age 38.26 yrs), 17.39% had hypertension, 2.23% had coronary artery disease; none was diabetic. Tobacco users and alcohol consumers were 24/46 (52.17%) cases each. ECA was found in 14/46 (30.44%) cases. Seven of these 14 (50%) i.e., 7/46 cases (15.21%) had carotid occlusion, four had <50%, three had >70% stenosis. ‘Smoking and smokeless tobacco use’ was found in 71.42% (10/14) symptomatic carotid lesions compared to 43.75% (14/32) strokes without carotid lesions. Prevalence odds ratio for tobacco use and ECA was 3.21 (95% CI: 0.83-12.44) while that of alcohol and ECA was 1.33 (95% CI: 0.38-4.72).

Conclusion:

Prevalence of ECA in strokes <50 years was high due to lifestyle factors which predispose to atherosclerosis at younger age.Key Words: Alcohol, extracranial carotid atherosclerosis, lifestyle factors, smoking, young stroke  相似文献   
6.
The present study concerns responsiveness of pre- and postsynaptic 5-hydroxytryptamine (5-HT)-1A receptors in a rat model of tardive dyskinesia (TD). Vacuous chewing movements (VCMs) in rats are widely accepted as an animal model of TD. Results show that haloperidol injected at a dose of 1 mg/kg twice a day for 5 weeks elicited VCMs, which increased in a time dependent manner following the drug administration for 3-5 weeks. Tolerance was produced in motor coordination during the potentiation of VCMs. Exploratory activity in an open field and in an activity box decreased in haloperidol treated animals. The effects of 8-hydroxy-2-(di-n-propylamino)tetraline (8-OH-DPAT; 0.5 mg/kg) were monitored 48-h after withdrawal from repeated administration of haloperidol. 8-OH-DPAT-induced locomotion was greater in haloperidol treated rats. 5-HT synthesis increased in haloperidol treated animals, while 8-OH-DPAT-induced decreases of 5-HT synthesis were greater in repeated haloperidol than repeated saline injected animals. The results suggest that an increase in the effectiveness of somatodendritic 5-HT-1A receptors may decrease the inhibitory influence of 5-HT on the activity of dopaminergic neurons to precipitate VCMs. The 5-HT-1A agonist may help to alleviate neuroleptic-induced TD.  相似文献   
7.
Objective: To determine the early outcomes of limb salvage surgery with mega prosthesis.Methods: This retrospective study was conducted at Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC) from 1st January 2017 till 31st January 2020. Data like demographics, histopathology, functional and survival outcomes were retrieved from the Hospital Information System. Musculoskeletal Tumor Society (MSTS) score was used to evaluate the functional outcomes after the surgery. For survival analyses, Kaplan-Meier curve was applied. Prosthesis joint infection, amputation rate, metastasis, mortality rate, and recurrence were also recorded. Results: This study included 43 patients who underwent limb salvage surgery with endoprosthesis reconstruction at SKMCH&RC. The mean age at the time of diagnosis was (26.5±15.8) years. Patients with distal femoral replacement had the highest MSTS scores (81.45±9.70) while those with proximal humerus replacement has the lowest MSTS scores (56.8±11.2). There was a strong association between site of tumor and MSTS (F=3.30, P=0.017). We also found a correlation between surgical site infection and MSTS scores (r=0.484, P=0.001). Patients with recurrence also had significantly lower MSTS scores (P<0.05). The cumulative survival rate at the end of two-year follow-up was (71.4±17.1)% in proximal femur tumor patients, (88.0±7.8)% in distal femur tumor patients, and (50.0±3.5)% in proximal humerus tumor patients. Besides, patients with Ewing sarcoma had the highest survival rate (97.5±11.0)% while patients with chondrosarcoma had the lowest survival rate (77.8±13.9)%. Conclusions: Limb salvage surgery with mega-prosthesis can be performed with satisfactory functional and survival outcomes, but further studies are needed to compare it with other limb salvage methods. This study can be used as a reference for future studies.  相似文献   
8.
ZnO is one of the most promising and efficient semiconductor materials for various light-harvesting applications. Herein, we reported the tuning of optical properties of ZnO nanoparticles (NPs) by co-incorporation of Ni and Ag ions in the ZnO lattice. A sonochemical approach was used to synthesize pure ZnO NPs, Ni–ZnO, Ag–ZnO and Ag/Ni–ZnO with different concentrations of Ni and Ag (0.5%, 2%, 4%, 8%, and 15%) and Ni doped Ag–ZnO solid solutions with 0.25%, 0.5%, and 5% Ni ions. The as-synthesized Ni–Ag–ZnO solid solution NPs were characterized by powdered X-ray diffraction (pXRD), FT-IR spectroscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), UV-vis (UV) spectroscopy, and photoluminescence (PL) spectroscopy. Ni–Ag co-incorporation into a ZnO lattice reduces charge recombination by inducing charge trap states between the valence and conduction bands of ZnO and interfacial transfer of electrons. The Ni doped Ag–ZnO solid solution NPs have shown superior 4-nitrophenol reduction compared to pure ZnO NPs which do not show this reaction. Furthermore, a methylene blue (MB) clock reaction was also performed. Antibacterial activity against E. coli and S. aureus has inhibited the growth pattern of both strains depending on the concentration of catalysts.

The synergic effect of Ni and Ag in Ni–Ag–ZnO solid solutions has tuned the optoelectronic properties of ZnO for photoreduction reactions.  相似文献   
9.
Histoid leprosy is extremely rare in children. Molluscum contagiosum–like lesions in the setting of histoid leprosy is a highly atypical presentation and may signify the process of “transepidermal elimination” in lesions with high bacillary load. A case of histoid leprosy with umbilicated papules and nodules mimicking molluscum contagiosum is reported in a 10‐year‐old Indian boy.  相似文献   
10.
A nosocomial outbreak of Crimean-Congo hemorrhagic fever occurred in Rawalpindi, Pakistan in February 2002. The identified index case died shortly after admission to a hospital. Two of the health care workers became secondary cases; one of them died on day 13 after coming in contact with the index case. The other secondary case was successfully treated with oral ribavirin.  相似文献   
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