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41.
The aim of this study was to evaluate the use of different fixatives on the reliability of histopathological changes in a rabbit model of proliferative vitreoretinopathy (PVR). Twenty eyes from 10 rabbits were divided into four groups. The right eyes were used in two experimental groups (each n = 5), and the left, in two control groups (each n = 5). Using a newly developed scleral incision marker, an oblique scleral incision was standardized in the experimental groups, followed by intravitreal injection of 0.4 ml autologous blood and the left for wound repair for four weeks. Eyes were enucleated at four weeks. The groups differed in the type of used fixative solution (formaldehyde 4% vs. 1% buffered formaldehyde and 1.25% glutaraldehyde). The eyes were evaluated for the development of fibrosis, retinal detachment (RD), and processed for histopathology. Fibrous ingrowth of a variable degree was present in the experimental groups originating from the trauma site. Experimental eyes fixed with formaldehyde 4% had RD extension that was greater than that fixed in formaldehyde/glutaraldehyde mixture; however, the difference did not reach statistical significance (P = 0.15). This difference was not fully explained by the fibrosis which developed. In addition, in control groups, formaldehyde 4% induced a fixative-dependent retinal separation that was absent in eyes fixed with formaldehyde/glutaraldehyde mixture (P = 0.03). In conclusion, a mixture of buffered formaldehyde 1% and glutaraldehyde 1.25% combined with standardized scleral incision resulted in consistent pathological changes. A reliable PVR model is a condition sine qua non to evaluate antifibrotic treatment strategies.  相似文献   
42.

Purpose

The adequate perioperative antibiotic prophylaxis in maxillofacial surgery is still under discussion due to the wide range of hard and soft tissue procedures as well as contaminated, semi-contaminated and clean surgical sides. Perioperative antibiosis is an easy applicable tool that can be used to decrease nosocomial morbidity and mortality by reducing the rate of infections. We compared strictly perioperative antibiosis with an extended postoperative prophylactic antibiosis.

Materials and methods

In this study, 901 consecutive patients, from a tertiary care maxillofacial surgery department were included and distributed into two groups: The first group received peri- and postoperative antibiotic prophylaxis (PP; n = 365) from the day of operation until the fifth day postoperatively. The second group was treated with single shot prophylaxis with intraoperative repetition as needed (SSP; n = 536) only. Furthermore, the patients were grouped according to their main diagnosis and surgical procedure. For comparison, general anamnestic data, cultured bacteria and resistances, number of surgical site infections and duration of hospitalization were compared.

Results

There were no statistically significant differences in general diseases or extent of surgery between the groups. There was no statistical difference in the surgical site infections between the groups regardless of their diagnosis. There were significant correlations between tracheotomised patients (p < 0.001) as well as patients with a higher BMI (p = 0.009) and the incidence of surgical site infections. Most common cultured bacteria were staphylococci.

Conclusion

Based on the findings of the study, we believe that a perioperative antibiosis delivers a sufficient prophylaxis for patients undergoing maxillofacial surgery procedures.
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Vascular endothelial growth factor (VEGF) is an important cerebral angiogenic and permeability factor under hypoxia. There is a need to find effective molecules that may ameliorate hypoxia‐induced cerebral oedema. In silico identification of novel candidate molecules that block VEGF‐A site were identified and validated with a Ramachandran plot. The active site residues of VEGF‐A were detected by Pocketfinder, CASTp, and DogSiteScorer. Based on in silico data, three VEGF‐A blocker (VAB) candidate molecules (VAB1, VAB2, and VAB3) were checked for improvement in cellular viability and regulation of VEGF levels in N2a cells under hypoxia (0.5% O2). Additionally, the best candidate molecule's efficacy was assessed in male Sprague‐Dawley rats for its ameliorative effect on cerebral oedema and vascular leakage under hypobaric hypoxia 7260 m. All experimental results were compared with the commercially available VEGF blocker sunitinib. Vascular endothelial growth factor‐A blocker 1 was found most effective in increasing cellular viability and maintaining normal VEGF levels under hypoxia (0.5% oxygen) in N2a cells. Vascular endothelial growth factor‐A blocker 1 effectively restored VEGF levels, decreased cerebral oedema, and reduced vascular leakage under hypobaric hypoxia when compared to sunitinib‐treated rats. Vascular endothelial growth factor‐A blocker 1 may be a promising candidate molecule for ameliorating hypobaric hypoxia‐induced vasogenic oedema by regulating VEGF levels.  相似文献   
46.
Clinical Rheumatology - Considering the pathologic significance of inflammation and oxidative stress in rheumatoid arthritis (RA) as well as the antioxidant, anti-inflammatory and hypolipidemic...  相似文献   
47.
Clinical Rheumatology - Adult-onset Still’s disease (AOSD) characterized by a high spiking fever, skin rash, arthritis, and leukocytosis. The aim of the present study was considering the...  相似文献   
48.
Growth differentiation factor 15 (GDF15) plays an important role in cancer pathophysiology and prognosis. However, limited studies analyzed its level and prognostic value in acute myeloid leukemia (AML) patients. This study included 56 adult AML patients. Serum GDF15 level was measured at diagnosis in all patients by enzyme-linked immunosorbent assay. Remission and survival statuses were assessed at 90 days following treatment. GDF15 level was significantly higher in patients than in controls (P < 0.001). GDF15 level correlated positively with age (P < 0.001), hemoglobin level (P = 0.027), and platelet count (P = 0.024). High GDF15 above the median level was associated with inferior OS (P = 0.044) together with high platelet count (P = 0.006) and high bone marrow blast percent (P = 0.038). There was no statistically significant difference between patients with GDF15 above and below the median level regarding DFS (P = 0.881). On multivariate analysis for OS, GDF15 level was an independent risk factor (P = 0.047). In conclusion, serum GDF15 level is significantly elevated in AML patients and high GDF15 level is associated with inferior OS.  相似文献   
49.
Exhaled nitric oxide is age-dependent in asthma   总被引:1,自引:0,他引:1  
We determined whether the exhaled nitric oxide (eNO) level in asthmatics is age-dependent. Eighty-seven asthmatic patients aged 2-41 years were studied. Hyperreactivity to adenosine 5'-monophosphate (AMP) was used to confirm asthma (相似文献   
50.
The impact of bone marrow fibrosis grade on the prognosis of patients with chronic myelomonocytic leukemia (CMML) remains controversial. Therefore, we examined the records of 82 patients diagnosed with CMML at our institution and summarized baseline characteristics and molecular profiles by subgroups of absent or mild (grades 0/1) and moderate (grade 2) fibrosis. Cox proportional hazards models were constructed to assess the prognostic significance of fibrosis grade. Grade 2 fibrosis was identified in 63 patients (76.8%), grade 1 in 16 patients (19.5%), and grade 0 in 3 patients (3.7%). Grade 2 fibrosis was associated with reduced hemoglobin levels (median 9.75 vs 11.0 g/dL in grade 0/1; p?=?0.04) and increased percentages of ringed sideroblasts (7.5 vs 0%; p?=?0.008). In multivariable analysis, grade 2 fibrosis was an independent predictor of poor overall survival (OS; 95% CI 1.32–6.35; HR 2.90; p?=?0.008), but not event-free survival (EFS; 95% CI 0.62–2.67; HR 1.28; p?=?0.50). Absolute neutrophil count (ANC) was found to impact OS (95% CI 1.01–1.09; HR 1.05; p?=?0.009), while both ANC (95% CI 1.00–1.07; HR 1.04; p?=?0.04) and peripheral blood blast percentage (95% CI 1.02–1.32; HR 1.16; p?=?0.02) impacted EFS. These results implicate fibrosis grade is an important indicator of prognosis, with high-grade fibrosis predicting inferior survival. Given the prevalence of marrow fibrosis in CMML, fibrosis grading should be incorporated into prognostic assessment and therapeutic decision-making.  相似文献   
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