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11.
AIM:To investigate a dual labeling technique,which would enable real-time monitoring of transplanted embryonic stem cell(ESC) kinetics,as well as long-term tracking.METHODS:Liver damage was induced in C57/BL6 male mice(n = 40) by acetaminophen(APAP) 300 mg/kg administered intraperitoneally.Green fluorescence protein(GFP) positive C57/BL6 mouse ESCs were stained with the near-infrared fluorescent lipophilic tracer 1,1-dioctadecyl-3,3,3,3-tetramethylindotricarbocyanine iodide(DiR) immediately before transplantationinto the spleen.Each of the animals in the cell therapy group(n = 20) received 5 × 10 6 ESCs 4 h following treatment with APAP.The control group(n = 20) received the vehicle only.The distribution and dynamics of the cells were monitored in real-time with the IVIS Lumina-2 at 30 min post transplantation,then at 3,12,24,48 and 72 h,and after one and 2 wk.Immunohistochemical examination of liver tissue was used to identify expression of GFP and albumin.Plasma alanine aminotransferase(ALT) was measured as an indication of liver damage.RESULTS:DiR-stained ESCs were easily tracked with the IVIS using the indocyanine green filter due to its high background passband with minimal background autofluorescence.The transplanted cells were confined inside the spleen at 30 min post-transplantation,gradually moved into the splenic vein,and were detectable in parts of the liver at the 3 h time-point.Within 24 h of transplantation,homing of almost 90% of cells was confirmed in the liver.On day three,however,the DiR signal started to fade out,and ex vivo IVIS imaging of different organs allowed signal detection at time-points when the signal could not be detected by in vivo imaging,and confirmed that the highest photon emission was in the liver(P 0.0001).At 2 wk,the DiRsignal was no longer detectable in vivo ;however,immunohistochemistry analysis of constitutively-expressed GFP was used to provide an insight into the distribution of the cells.GFP +ve cells were detected in tissue sections resembling hepatocytes and were dispersed throughout the hepatic parenchyma,with the presence of a larger number of GFP +ve cells incorporated within the sinusoidal endothelial lining.Very faint albumin expression was detected in the transplanted GFP +ve cells at 72 h;however at 2 wk,few cells that were positive for GFP were also strongly positive for albumin.There was a significant improvement in serum levels of ALT,albumin and bilirubin in both groups at 2 wk when compared with the 72 h time-point.In the cell therapy group,serum ALT was significantly(P = 0.016) lower and albumin(P = 0.009) was significantly higher when compared with the control group at the 2 wk time-point;however there was no difference in mortality between the two groups.CONCLUSION:Dual labeling is an easy to use and cheap method for longitudinal monitoring of distribution,survival and engraftment of transplanted cells,and could be used for cell therapy models.  相似文献   
12.

Background

Anaplastic thyroid carcinoma (ATC) is the most aggressive form of thyroid cancer and it has an extremely poor prognosis. Rapid airway compromise is the main cause of death in patients with ATC.

Methods

The present study is based on a retrospective review of clinical data of patients with ATC treated over the last decade in a tertiary referral center.

Results

Between January 1998 and December 2010, 31 patients (13 males: 18 females) with a mean age of 74 years (range: 54–90 years) had a diagnosis of ATC made on fine-needle aspiration (n = 29) or biopsy (n = 2). Eight patients underwent total thyroidectomy and lymph node dissection, and five patients had attempted surgery but the procedure was abandoned because of inoperability. Airway compromise was clinically apparent in 11 patients. Five patients had tracheal stents inserted, with a median survival of 2 months (range: 1–36 months). In the whole cohort, 29 patients died of the disease, with a mean survival of 7 months (range: 1–36 months).

Conclusions

Survival of patients with undifferentiated thyroid cancer is severely compromised by airway obstruction. Palliation with tracheal stenting can rescue catastrophic airway obstruction but offers minimal survival benefit.  相似文献   
13.
BackgroundVentilator associated pneumonia (VAP) is an important source of morbidity and mortality in patients receiving mechanical ventilation. VAP is associated with prolongation of mechanical ventilation, ICU and hospital stay and increases in costs.MethodsQuality improvement project. Mechanically ventilated patients received oral care every 8 h with chlorhexidine 2%. A formal process was developed to evaluate compliance with the following ventilator bundle initiatives: head of the bed elevation to 30–45°, daily sedation vacation and assess the readiness to extubate, providing peptic ulcer disease prophylaxis and providing deep vein thrombosis prophylaxis (unless contraindicated).ResultsThe rate of VAP before starting the project, in the first 6 months of year 1431H, was 16.2 cases/1000 ventilator days. Six month after inception of the quality improvement project, the VAP rates decreased to 5.6 cases/1000 ventilator days at the end of 1431H, and at the end of 1432H, it was 5.5 cases/1000 ventilator days. This leads to significant reduction in mortality (adjusted according to APACHE II) from 23.4% to 19.1% (p value 0.024) and the length of stay in ICU from 9.7 to 6.5 days (p value 0.00002).ConclusionThe combination of regular oral hygiene with chlorhexidine 2% and rigorous implementation of ventilator care bundle was associated with significant reduction in VAP rate in mechanically ventilated patients. This has led to reduction in length of stay in ICU from 9.7 to 6.5 days and reduction in mortality from 23.4% to 19.1%.  相似文献   
14.
PurposeThe aim of study is to assess the role of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and correlation with tumour angiogenesis in evaluation of urinary bladder cancer.Material and MethodsThe study included 81 patients with recent presumed diagnosis of bladder tumour or who came for follow up after management of histopathologically proven bladder cancer. All had DCE-MRI with time–signal intensity curve. The radiologic results then correlated with the histopathologic results using both haematoxylin and eosin stain and immuno-histochemical staining for localization and evaluation of CD34 immunoreactivity as a detector for the microvessel density (MVD) and tumour angiogenesis.ResultsSeventy-one cases were pathologically proven to be malignant: 41 cases (58%) showed type III time–signal intensity curve (descending); 22 cases (31%) showed type II (plateau); and 8 cases (11%) showed type I (ascending) curve. The sensitivity of DCE-MRI in stage T1 bladder tumour was 80%; in stage T2, it was (90.9%); and in stage T3, it was (96.9%). Overall accuracy of DCE-MRI in tumour staging was 89.5% and P = .001 (significant). Values more than the cutoff value = 76.13 MVD are cystitis with sensitivity (90%), specificity (91%), and P value is .001, which is statistically highly significant.ConclusionThere is a strong positive association between DCE-MRI (staging and washout slope of the time–signal intensity curve) with histopathologic grade, tumour stage, and MVD in bladder cancer. So, DCE-MRI can be used as reliable technique in preoperative predictions of tumour behavior and affect the planning of antiangiogenetic therapy.  相似文献   
15.
Objective: To formulate solid lipid microparticles (SLMs) encapsulating doxycycline hydrochloride (DH) and metronidazole (MT) for the treatment of periodontal diseases.

Methods: SLMs were prepared applying hot homogenization method, using different types of lipids and stabilized with various types and concentrations of surfactants. The optimized formula was subjected to freeze-drying followed by incorporation into poloxamer gel. Microbiological and clinical evaluation of the selected SLMs on patients suffering from periodontal diseases was performed.

Results: SLMs could entrap high percentage of both drugs (81.14% and 68.75 % for doxycycline hydrochloride and metronidazole respectively). Transmission electron microscopy images of SLMs showed nearly spherical particles. Freeze-dried SLMs showed satisfactory stability for three months. Combined drugs were molecularly dispersed in SLMs. Incorporation of the freeze-dried SLMs powder in poloxamer gel could control the drugs release for 72 h. In-vivo study revealed effective and safe use of SLMs gel for periodontitis treatment. Significant improvement in both microbiological and clinical parameters was observed as compared to scaling and root planing alone.

Conclusion: The formulated SLMs gel offers an applicable dosage form that can be injected directly into the periodontal pocket as adjunctive to scaling and root planing.  相似文献   

16.
BackgroundBladder cancer is the most prevalent form of cancer in men among Egyptians, for whom tobacco smoke exposure and Schistosoma haematobium (SH) infection are the major risk factors. We hypothesized that functional polymorphisms in NAD(P)H:quinone oxidoreductase 1 (NQO1) and superoxide dismutase 2 (SOD2), modulators of the effects of reactive oxidative species, can influence an individual's susceptibility to these carcinogenic exposures and hence the risk of bladder cancer.MethodsWe assessed the effects of potential interactions between functional polymorphisms in the NQO1 and SOD2 genes and exposure to smoking and SH infection on bladder cancer risk among 902 cases and 804 population-based controls in Egypt. We used unconditional logistic regression to estimate the odds ratios (OR) and confidence intervals (CI) 95%.ResultsWater pipe and cigarette smoking were more strongly associated with cancer risk among individuals with the TT genotype for SOD2 (OR [CI 95%] = 4.41 [1.86–10.42]) as compared with those with the CC genotype (OR [CI 95%] = 2.26 [0.97–6.74]). Conversely, the risk associated with SH infection was higher among the latter (OR [CI 95%] = 3.59 [2.21–5.84]) than among the former (OR [CI 95%] = 1.86 [1.33–2.60]). Polymorphisms in NQO1 genotype showed a similar pattern, but to a much lesser extent. The highest odds for having bladder cancer following SH infection were observed among individuals with the CC genotypes for both NQO1 and SOD2 (OR [CI 95%] = 4.41 [2.32–8.38]).ConclusionOur findings suggest that genetic polymorphisms in NQO1 and SOD2 play important roles in the etiology of bladder cancer by modulating the effects of known contributing factors such as smoking and SH infection.  相似文献   
17.
Aim: Catheter associated urinary tract infections (CAUTI) are the most common hospital-acquired infection in ICUs. The aim of this study was to estimate the effectiveness of an intervention program by implementing urinary catheter bundle elements to reduce the CAUTI frequency in an ICU. Methods: The intervention study was conducted over a period of 6 months. During a pre-intervention phase, the base line catheter associated CAUTI incidence rates were determined and compared with the incidence rates during the post-intervention phase. The compliance of health care staff with urinary catheter bundle elements was also measured. The implemented CAUTI prevention bundle consisted of hand hygiene, wearing personal protective equipment, use of disposable gloves, cleansing of urethral meatus prior to catheter insertion using sterile saline, assessment of catheter need, aseptic urine sampling technique, and correct draining bag positioning.Results: During the study period, 55 out of 77 patients were diagnosed with a CAUTI. The mean CAUTI incidence rate for the pre-intervention period was 90.12/1,000 catheter days and for the post intervention phase 65.69/1,000 catheter days. The CAUTIs rate was inversely proportional to insertion bundle elements and maintenance bundle elements compliance rate. This negative relationship was statistically significant only with maintenance bundle elements (p=0.042) (rs=–0.828). The compliance rate of the ICU nurses to the bundle elements was raised to 100% during the last 2 months of the post intervention phase.Conclusion: Increased compliance to recommended catheter associated urinary tract infections preventive practices reduced the incidence of CAUTI in an ICU unit. It is simple and effective and is recommended as a part of patient safety culture.  相似文献   
18.
The arteriovenous oxygen difference (a-vO(2) difference), a measure of peripheral muscle oxygen extraction-utilization during exercise, is reduced in antiretroviral-treated patients with human immunodeficiency virus (HIV), thus causing a shift in the cardiac output-oxygen consumption (Q-VO(2)) relationship. We investigated the impact of recombinant human GH (rhGH) treatment on a-vO(2) difference and the Q-VO(2) relationship during submaximal exercise by randomizing 12 HIV-infected patients (mean +/- sem: age, 43.3 +/- 1.5 yr; body mass, 69.5 +/- 2.9 kg; body mass index, 22.4 +/- 0.9 kg/m(2); maximum oxygen consumption, 33.6 +/- 1.5 ml/kg x min), with documented unintentional weight loss (>or=10% within the preceding 12 months) despite antiretroviral therapy, to receive 3 months of rhGH (6 mg/d) in a double-blind, placebo-controlled, cross-over trial. We assessed Q (determined noninvasively using CO(2) rebreathing), and subsequently a-vO(2) difference, from Q-VO(2) relationships. At study entry, the mean slope (8.1 +/- 1.0 liters/min x 1-liter increase in VO(2)) and intercept (3.1 +/- 1.3 liters/min), generated from each patient's Q-VO(2) relationship, were greater and lower, respectively, than those reported for healthy individuals (6.0 and 4.0, respectively), thereby indicating a deficit in the a-vO(2) difference. After 3 months of rhGH treatment, the slope decreased to 7.0, and the intercept increased to 3.5. After 1 month of rhGH treatment, the a-vO(2) difference (at a VO(2) of 1250 ml/min) significantly (P < 0.05) increased (17.1 +/- 8.9%) from baseline (9.92 +/- 0.51 ml/dl) and remained elevated (10.39 +/- 0.48 ml/dl) after 3 months of treatment. No significant changes were seen with placebo. Therefore, treatment with rhGH leads to an improvement in peripheral muscle oxygen extraction-utilization and the Q-VO(2) relationship during exercise in patients with HIV-associated wasting despite antiretroviral therapy.  相似文献   
19.

Background

The purpose of this study was to assess prospectively operative results and complications of treatment of cervical spinal canal stenosis (CCS) by anterior cervical discectomy and fusion (ACDF) using a newly introduced Alexandria Modular Cage-Plate Construct (AMCPC).

Methods

Fifteen patients (eight males, seven females) with symptomatic CCS were treated by ACDF, with a mean age of 51.2 years. Post-operative assessment depended upon clinical and radiological results.

Results

Total number of operated levels was 25 levels, with a mean 1.67 levels/patient. Mean operative time was 69.6 min/level and 116 min/patient. Average blood loss was 78 mL/level and 130 mL/patient. Mean hospital stay was 2.8 days. Post-operative dysphagia/dysphonia persisted in one patient for 1 year. One patient developed C5 radiculopathy with grade 2 deltoid weakness that recovered after 3 months. According to Odom’s criteria, results were excellent in 13 patients (86.67 %), good in 1 (6.67 %), and fair in 1 patient. In 13 patients (23 cage-plates, 92 %), the implant showed to be completely contained until the end of follow-up (24 months). One patient had a broken screw and one had screw backing-out, both did not necessitate revision. The achieved sagittal profile was maintained without sinking-in of any cage.

Conclusion

AMCPC can be used safely for a variety of disorders requiring instrumentation and fusion. It is advantageous to stand-alone cage and to rigid cage-plates when intraoperative flexibility is needed. It overcomes the disadvantages of stand-alone cage, sinking-in, cage dislodgement and post-operative rekyphosis. In addition, it obviates the need for wearing post-operative neck collar.  相似文献   
20.
Rosmarinus species are aromatic plants that mainly grow in the Mediterranean region. They are widely used in folk medicine, food, and flavor industries and represent a valuable source of biologically active compounds (e.g., terpenoids, flavonoids, and phenolic acids). The extraction of rosemary essential oil is being done using three main methods: carbon dioxide supercritical extraction, steam distillation, and hydrodistillation. Furthermore, interesting antioxidant, antibacterial, antifungal, antileishmanial, anthelmintic, anticancer, anti‐inflammatory, antidepressant, and antiamnesic effects have also been broadly recognized for rosemary plant extracts. Thus the present review summarized data on economically important Rosmarinus officinalis species, including isolation, extraction techniques, chemical composition, pharmaceutical, and food applications.  相似文献   
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