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1.
The current literature suggests that the antibacterial effect of leukocyte- and platelet-rich plasma (L-PRP) is directly related to platelet and leukocyte concentrations. The aim of this study was twofold: first, to evaluate the antimicrobial effect of L-PRP against selected bacterial strains in vitro, and second, to correlate this effect with leukocyte and platelet content in the final concentration. Blood was collected from 20 healthy males, and L-PRP, acellular plasma (AP), and autologous thrombin were consecutively prepared. Flow cytometry analysis of the blood, L-PRP, and AP was performed. The L-PRP gel, liquid L-PRP, and thrombin samples were tested in vitro for their antibacterial properties against seven selected bacterial strains using the Kirby–Bauer disk-diffusion method. There was notable antimicrobial activity against selected bacterial strains. No statistically significant correlations between antimicrobial activities and the platelet concentration in L-PRP were observed. Statistically significant positive correlations between selected leukocyte subtypes and antimicrobial activity were noted. A negative correlation was found between elevated monocyte count and antimicrobial activity of L-PRP against one bacterial strain studied. L-PRP possesses antimicrobial activity and can be potentially useful in the fight against certain postoperative infections. The bactericidal effect of L-PRP is caused by leukocytes, and there exists a relationship among selected leukocyte subtypes and L-PRP antimicrobial activity.  相似文献   
2.
Background  Surgical procedures enhance production of pro- and anti-inflammatory cytokines and angiogenic factors that play a pivotal role in the immunological response to surgical trauma and take part in the pathogenesis of tumor growth and adhesions formation. The purpose of the study was to access the influence of low-pressure CO2 pneumoperitoneum on the inflammatory and angiogenic responses during the postoperative period after laparoscopy. Methods  The study group consisted of 40 patients, operated on due to cholelithiasis using standard-pressure (n = 20) and low-pressure (n = 20) CO2 pneumoperitoneum. Serum concentration of interleukin (IL)-6, IL-8, IL-10, vascular endothelial growth factor (VEGF)-A, and endostatin were measured before and at 6, 24, and 48 h after surgery with commercially available enzyme-linked immunosorbent assay (ELISA). Results  Concentrations of IL-6 increased significantly after the operations in both groups. No differences were observed between the groups in regards to IL-6, IL-8, and IL-10 levels. Concentrations of VEGF-A measured at 6 and 48 h were significantly lower in patients who underwent laparoscopies performed with low-pressure pneumoperitoneum. No significant variations were observed in endostatin serum concentration. Concentrations of the studied parameters were not influenced by duration of surgery or by age, gender, or body mass index (BMI) of the patients. Conclusions  The results obtained in our study do not show any significant differences between studied operative procedures with regards to systemic inflammatory response. Changes in the concentrations of VEGF-A and endostatin observed in the studied population may suggest this technique is more favorable with regards to angiogenesis process intensity, along with all its consequences and implications.  相似文献   
3.
Growing experience in interventional cardiology leads to the use of large diameter of vascular equipment. In some instances, the so-called hybrid procedures are performed. After performing the interventional procedure, the opening in ventricular wall is closed surgically. Our intention was to check if the MVSDO can be used to close the perforation in the heart after the interventional cardiology procedure performed through the left ventricular (LV) free wall. In three pigs under general anesthesia, the heart was exposed through a small substernal incision. The LV was punctured and an 18F sheath was introduced into the LV. A 14 mm MVSDO was inserted through the 10F Delivery System. Using both the echocardiographic and angiographic guidance, the MVSDO was placed on the LV wall to close the opening in the LV. Time and volume of bleeding was recorded. In all cases the occluder was successfully placed closing the opening, bleeding observed after deployment of occluder lasted for approximately 2 min. We think MVSD occluder can be used to close the LV free wall perforation after hybrid interventional cardiac procedure. Early bleeding through MVSDO might be resolved by the manufacturing of new occluder with better sealing properties.  相似文献   
4.
Anatomical considerations of selective pudendal neurectomy   总被引:3,自引:0,他引:3  
The pudendal nerve was examined in 100 cadavers of both sexes. Because of the variable number of trunks of the pudendal nerve, 5 types were distinguished: one-trunked; two-trunked, rectopudendal; two-trunked, pudendo-penile (or-clitoridal); three-trunked, recto-perineo-penile (or-clitoridal); four-trunked, recto-perineo-perineopenile (or-clitoridal). The authors' suggestions make it possible to perform selective pudendectomy, consisting in denervation of the sphincter urethrae muscle by neurectomy of the perineal branches of the pudendal nerve.  相似文献   
5.
AIM: To check on reproducibility of parameters of the cutaneous electrogastrogram registered at a close or a distant time span. METHODS: Twenty-two volunteers recruited by an advertisement (11 females and 11 males, median age 25 years, range: 18-35) underwent three surface electrogastrography examinations of which two were taken on consecutive days and the third one was accomplished at least 2 weeks before or after the two other sessions. The examination involved a 30-min fasted recording, followed by a 90-min postprandial registration after intake of a 394-kcal mixed solid-liquid test meal. RESULTS: Parameters of the electrogastrogram pertaining to the frequency of the gastric slow waves exhibited good to moderate reproducibility, whereas fair reproducibility characterized parameters expected to describe the power of gastric slow waves. With the exception of the difference fed minus fasted power (DeltaDP), in no instance was the medium term reproducibility any worse than the short term one. Categorical data analysis revealed that the relative time share of normogastria postprandially exhibited a better reproducibility than in the fasted period. The Cohen's kappa-value of 0.459 for the DeltaDP for the medium term reproducibility placed this parameter within the range of moderate agreement between repeat examinations. Of the two two-parameter combinations considered, the alliance of the fasted and fed normogastria performed worse than any of those parameters considered alone, whereas a combination of the DeltaDP with the fed-state normogastria revealed a kappa-value amounting to 0.510 for the medium term reproducibility. CONCLUSIONS: The feasibility of some electrogastrographic parameters to convey clinically useful information may be hampered by their fair reproducibility. Recoding of parameters of the cutaneous electrogastrogram from primary continuous to secondary categorical may help achieve a better agreement between repeat examinations.  相似文献   
6.
Violence at the workplace--a questionnaire survey of nurses.   总被引:2,自引:0,他引:2  
BACKGROUND: In the health sector, anywhere in the world nurses are one of the most exposed groups to violence. However, it is not obvious that psychiatric nurses (PNs) are more exposed to aggression and burnout. OBJECTIVES: To determine the nature and effects of aggressive acts towards nursing staff in psychiatric and other medical services in Poland. METHODS: Various questionnaires (Stress at Work Scale, General Health Questionnaire, Maslach Burnout Inventory, Work Satisfaction Scale), were distributed among psychiatric (N=78) and non-psychiatric nurses (N-PNs) (N=335). A 92.6% response rate was achieved. RESULTS: Significant differences were found between PNs and non-psychiatric counterparts with respect to their experiences of violence. The most frequently reported incident was verbal abuse, followed by threats and physical assault. Patients were significantly more frequent perpetrators in psychiatric wards than in others. The level of intra-staff aggression did not significantly vary between groups, neither did the level of work satisfaction and absenteeism. CONCLUSION: The frequency of violent acts and stress related to them point out the strong need for the development of preventive programs to address the issue of violence at work.  相似文献   
7.
8.
OBJECTIVES: Resin-modified glass ionomer cements (RMGI) are hybrid materials prepared by incorporation of polymerizable components (typically 2-hydroxyethyl methacrylate (HEMA) with possible addition of multifunctional methacrylates) into a conventional acid-base mixture (a polymeric acid with powdered calcium fluoro-aluminosilicate glasses). During setting, the photopolymerization process and the acid-base reaction affect each other. The aim of this work was to examine the effect of a 45% aqueous solution of poly(acrylic acid) (PAA) and the liquid component of a commercial glass ionomer cement on HEMA and triethyleneglycol dimethacrylate (TEGDMA) photopolymerization. METHODS: The polymerization was initiated by 2,2-dimethoxy-2-phenylacetophenone (DMPA) and camphorquinone (CQ)/coinitiator system. The reaction course was monitored under Ar and air by isothermal differential scanning calorimetry. RESULTS: The main effect of addition of polyacid solution (PAA and commercial) up to 10wt% to HEMA on the polymerization initiated with DMPA was earlier onset of autoacceleration. For the process initiated by the CQ-based system, the addition of 5wt% of PAA solution strongly accelerated the polymerization and increased the conversion, both in Ar atmosphere as well as in air. TEGDMA photopolymerization was not influenced or slightly retarded by the presence of 3wt% of PAA solution (the upper limit of solubility), depending on the initiating system used. SIGNIFICANCE: Under initiation conditions used in curing of commercial dental products (CQ-based two component initiating system), the presence of polyacid-aqueous solution in HEMA-based photocurable component increases markedly the polymerization rate and the conversion both in Ar atmosphere as well as in air. This result contributes to a characterization of the setting process of RMGIs.  相似文献   
9.
PURPOSE: To evaluate the effect of lovastatin alone or combined with radiation on U87MG and FaDu cells in vitro and U87MG tumors in vivo. MATERIAL AND METHODS: Cell number, p21(WAF1) expression, apoptosis, reproductive cell death, and cell-cycle distribution were investigated after incubation of U87MG and FaDu cells in vitro. The effect of lovastatin (50 mg/kg/day) on tumor growth and on tumor growth delay after single-dose irradiation with 20 Gy was investigated using U87MG tumors in nude mice. RESULTS: Lovastatin dose dependently decreased cell number and proliferation of U87MG and FaDu cells. The proportion of cells in G0/G1 phase, apoptosis and p21 protein expression increased after lovastatin alone or combined with 4-Gy irradiation in both cell lines. Effects of lovastatin on cell cycle and cell number were more pronounced in U87MG compared to FaDu. No radiosensitization of clonogenic cells by lovastatin could be demonstrated in both cells lines, but the colony-forming ability after lovastatin alone was decreased in FaDu cells. In vivo, lovastatin decreased tumor volume over time but did not increase growth delay after irradiation of U87MG tumors with 20 Gy. CONCLUSION: The data support effects of lovastatin on proliferation, apoptosis and colony-forming ability in vitro and tumor volume in vivo. At the drug concentration achievable, lovastatin did not improve the effects of radiation on U87MG tumors in vivo.  相似文献   
10.
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