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1.
Agata Cieślik-Bielecka Paweł Reichert Rafał Skowroński Tomasz Bielecki 《Platelets》2019,30(6):728-736
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.
About 10% of patients with Lyme disease continue to experience musculoskeletal pain and cognitive dysfunction after recommended antibiotic treatment. This condition is called post-Lyme disease syndrome (PLDS) or post-treatment Lyme disease syndrome. These two terms are used interchangeably. The pathogenesis of PLDS has been controversial. The hypothesis that patients with PLDS may harbor hidden reservoirs of Borrelia burgdorferi after their initial antibiotic treatment is difficult to accept. The prospective, double-blind studies contradict this point of view. Also, recently published research applying xenodiagnosis to PLDS supports the opinion that PLDS most likely has an autoimmune background. Lengthy courses of antibiotics are not justified in patients with PLDS because of the lack of benefit, and they are fraught with hazards. Most patients with PLDS recover from persistent symptoms with time. However, it can take months before they feel completely well. 相似文献
3.
Piotr Podolec Grzegorz Kope? Jakub Podolec Piotr Wilko?ek Marek Krochin Pawe? Rubi? Marcin Cwynar Tomasz Grodzicki Krzysztof Zmudka Wies?awa Tracz 《Hypertension research》2007,30(12):1151-1158
The objectives of this study were to determine the relationship between carotid-femoral (cfPWV) and aortic pulse wave velocity (aPWV) and to compare their modulators and association with coronary artery disease (CAD). We studied 107 consecutive patients (68 men) with a mean age of 60.49+/-8.31 years who had stable angina and had been referred for coronary angiography. cfPWV and aPWV were measured simultaneously during cardiac catheterization using the Complior device and aortic pressure waveform recordings, respectively. Based on the presence or absence of significant coronary artery stenosis (CAS) patients were subdivided into a CAS+ or CAS- group. The mean values of cfPWV and aPWV were 10.65+/-2.29 m/s and 8.78+/-2.24 m/s, respectively. They were significantly higher in the CAS+ (n=71) compared with the CAS- (n=36) group and predicted significant CAS independently of cardiovascular risk factors and mean or systolic aortic blood pressure. aPWV and cfPWV were significantly correlated (r=0.70; p<0.001) but the degree of correlation differed significantly (p<0.03) between the CAS+ (r=0.74, p<0.001) and CAS- group (r=0.46, p=0.003). Age and mean aortic blood pressure were independent predictors for aPWV as well as cfPWV. In the receiver operating characteristic (ROC) analysis, aPWV and cfPWV had similar accuracy in identification of significant CAS (AUC [area under the ROC curve]=0.76 and 0.69, respectively; p=0.13). However, neither cfPWV nor aPWV was effective at differentiating the extent of CAD. In conclusion, aPWV and cfPWV are highly correlated parameters with similar determinants and comparable accuracy in predicting significant CAS. The strength of correlation between these two indices differed significantly between subjects with and those without CAS. 相似文献
4.
Analysis of reflex activity in cardiac sympathetic nerve induced by myelinated phrenic nerve afferents 总被引:2,自引:0,他引:2
Electrical stimulation of the phrenic nerve afferents evoked excitatory responses in the right inferior cardiac sympathetic nerve in chloralose-anaesthetized cats. The reflex was recorded in intact and spinal cats. The latency and threshold of the volley recorded from the phrenic nerve as well as of the cord dorsum potentials evoked by electrical stimulation of the phrenic nerve indicated that group III afferents were responsible for this reflex. The phrenicocardiac sympathetic reflex recorded in intact cats was followed by a silent period. The maximum amplitude of the reflex discharges was 800 microV, the latency was 83 ms and the central transmission time 53 ms. Duration of the silent period lasted up to 0.83 s. In spinal cats the reflex was recorded 5.5-8 h after spinalization. The maximum amplitude of the spinal reflex discharges ranged from 22 to 91 microV and the latency from 36 to 66 ms. 相似文献
5.
Pawe? Reichert Roman Rutowski Krzysztof Zimmer Jerzy Gosk Krzysztof Bogdan Roman Wiacek 《Chirurgia narzadów ruchu i ortopedia polska》2007,72(3):175-179
Purpose of work was estimation of the results of treatment of pseudoarthrosis of the long bone with the method of decortication, with use of autogenic bone depends on kind of pseudoarthrosis and kind of osteosynthesis. In the years 1995-2005 56 patients were treated because of pseudoarthrosis of long bone in our Clinic. Pseudoarthrosis is classified according to Weber-Cech classification. In the methodology of clinical estimation and subjective estimation of the patient Stewart and Hundley and Anderson classification were used. Union was achieved in 51 cases. Time of bone union achievement was 5 months. The results of treatment are depends on morfology of pseudoartrosis and are independs of kind of osteosynthesis. 相似文献
6.
Plasma alpha beta levels have been examined in sporadic Alzheimer's disease yielding conflicting results; both no difference and an increase in plasma concentrations of alpha beta42 and alpha beta40 in sporadic cases of AD as compared to controls have been reported. Elevated plasma alpha beta42 levels may be detected several years before the onset of symptoms (in mild cognitive impairment stadium). Levels of alpha beta40 and alpha beta42 were measured in plasma from 54 patients with AD, 39 subjects with MCI and 35 controls using a commercially available ELISA. Mean plasma alpha beta42 levels were significantly higher in MCI as compared to both AD (P < 0.001) and control subjects (P < 0.001), while alpha beta40 did not differ between the groups. No correlations were observed between alpha beta levels and age, MMSE scores or gender. According to ROC curve analysis the maximum accuracy in discriminating MCI versus both controls and AD subjects has been achieved using a cut-off value of 3.8. 相似文献
7.
Piotrowski WJ Marczak J Kurmanowska Z Górski P 《Archivum immunologiae et therapiae experimentalis》2004,52(6):435-440
INTRODUCTION: Oxidative lung damage may be associated with the destruction of alveolar cells. Type II alveolar epithelial cells (AECs),as progenitors of type I cells, are indispensable for the renovation of alveolar structure after lung injury. Extensive damage to type II cells could be responsible for unfavorable outcome. However, the susceptibility of type II AECs to oxidative stress is unclear. MATERIAL/METHODS: We investigated the susceptibility of freshly isolated and cultured rat type II AECs to oxidative stress (H2O2 and Fe2+). Thiobarbituric acid reactive substances (TBARS)were measured as indices of lipid peroxidation and cytotoxicity was estimated by the MTT test. Aminotriazol (ATZ), an inhibitor of intracellular catalase, was used to estimate the protective role of catalase. RESULTS: TBARS concentration increased significantly in freshly isolated, oxidant-exposed cells (4.0 +/-1.3 vs.8.3 +/-2.2 nmol/g protein, p=0.0313)and insignificantly in cultured cells (1.7 +/-0.4 vs.4.4 +/-1.7 nmol/g protein).ATZ was toxic even to cells not exposed to oxidants. Inhibition of catalase in cells exposed to oxidants resulted in an insignificant increase in TBARs:4.5 +/-1.5 vs.16.2 +/-3.9 nmol/g protein, p=0.0625,and 4.0 +/-0.8 vs.7.6 +/-4.0 for freshly isolated and cultured cells, respectively. Oxidative stress itself did not increase cytotoxicity. CONCLUSIONS: Type II AECs are not resistant to oxidative stress. We cannot, however, explain why cells with evidence of lipid peroxidation do not show increased cytotoxicity. The toxicity of ATZ is not related to oxidative cell damage. In cells exposed to oxidants, TBARS may fur-ther increase when catalase is inhibited, which suggests an important protective role for catalase. 相似文献
8.
Allergic angiitis and granulomatosis (Churg-Strauss syndrome) is one of the rare form of idiopathic (primary) vasculitis. It is characterized by asthma, blood hypereosinophilia and typical microscopic features: nectrotizing vasculitis, tissue infiltration by eosinophils and extravasal granulomas. We present an autopsy case of 55-years old man with Churg-Strauss syndrome complicated by eosinophilic myocarditis. 相似文献
9.
Adhesion molecules and their ligands in nasal polyps of aspirin-hypersensitive patients. 总被引:1,自引:0,他引:1
Maciej Kupczyk Izabela Kupry? Marian Danilewicz Ma?gorzata Bocheńska-Marciniak Anna Murlewska Pawe? Górski Piotr Kuna 《Annals of allergy, asthma & immunology》2006,96(1):105-111
BACKGROUND: Chronic inflammation with tissue eosinophilia plays a key role in the pathogenesis of asthma and nasal polyps in patients with aspirin hypersensitivity. OBJECTIVE: To evaluate the expression of vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule I (ICAM-1) and their ligands (the integrins lymphocyte function-associated antigen 1 and very late-activation antigen 4 [VLA-4]) in nasal polyps of patients with aspirin hypersensitivity compared with aspirin-tolerant individuals. METHODS: Immunohistochemical studies were performed using a peroxidase method and monoclonal antibodies on 6-microm-thick cryostat sections cut from frozen polyps collected during elective surgery from 21 aspirin-sensitive and 23 aspirin-tolerant patients. RESULTS: The mean +/- SD values of the semiquantitatively evaluated immunoexpression of ICAM-1, VCAM-1, and VLA-4 were significantly increased in patients with aspirin hypersensitivity compared with aspirin-tolerant patients (1.7 +/- 0.8 vs 0.9 +/- 0.8, P < .003; 1.8 +/- 0.8 vs 0.8 +/- 0.8, P < .001; and 2.2 +/- 0.7 vs 1.3 +/- 0.7, P < .001, respectively), whereas the mean +/- SD values of the expression of lymphocyte function-associated antigen 1 did not differ significantly (2.4 +/- 0.5 vs 2.2 +/- 0.9; P = .57). We found a correlation between the immunoexpression of VCAM-1 and its ligand VLA-4 in all studied tissue samples (r = 0.4; P < .02). CONCLUSIONS: In nasal polyps of aspirin-hypersensitive patients, up-regulation of the adhesion molecules ICAM-1 and VCAM-1 and the integrin VLA-4 may play an important role in the development of chronic eosinophilic inflammation. 相似文献
10.
We examined the possibility of establishment of patent infections after percutaneous exposure of parasite-naive pigs to 10,000
Oesophagostomum dentatum infective larvae (L3). At 5 weeks after percutaneous exposure the pigs were slaughtered and low numbers of adult O. dentatum were recovered from the large intestine. In addition, exsheathed L3 were intravenously injected into pigs, which resulted in the recovery of fourth-stage larvae (L4) from nodules in the lungs as well as of L4 and adult worms from the large intestine. This study demonstrates the ability of porcine nodular worms to establish in the
large intestine when pigs have been exposed percutaneously to infective larvae. It is possible that the larvae reach the large
intestine by invading blood veins or the lymphatic system at the site of penetration.
Received: 24 February 1998 / Accepted: 13 May 1998 相似文献