Ameliorative Effects of Propolis and Royal Jelly against CCl4-Induced Hepatotoxicity and Nephrotoxicity in Wistar Rats

Carbon tetrachloride (CCl₄) is known to have hepatotoxic and nephrotoxic effects. During the two-month CCl₄ exposure of Wistar rats, propolis extract (PE) and royal jelly (RJ) were added in order to test the potential protective effect against hepato-renal injury. Ketonuria, proteinuria, high creatinine and urea levels are the result of CCl₄-induced nephrotoxicity. Severe disorders of hematological indicators indicate anemia; high values of leukocytes indicate inflammatory condition. Cytogenetic impairments in hepatocytes, aggregation of platelets, and hypoproteinemia indicate severe liver impairment. Results suggest a more significant protective role of RJ compared to PE. Both extracts regulated proteinuria, ketonuria, hypoproteinemia and reduced platelet aggregation in the hepatic circulation. The increase in the number of erythrocytes (RBC) suggest protective effects against anemia; the decrease in the number of leukocytes can be linked to anti-inflammatory effects. PE and RJ have a beneficial effect against hepato-renal injury, anemia and anti-inflammatory conditions caused by CCl₄.     

Non linear anthropometric predictors in swimming

In this paper we have tried to identify the significance and character of the linear and non-linear relations between simple anthropometric predictors: body height (BH), body weight (BW), and body mass index, and swimming performance: freestyle swimming 50 (FS50) and 400 meters (FS400), in a sample of young (15 years old on average) male (N = 40) and female (N = 28) swimmers. Linear (general model: y = a+bx) and nonlinear regression (general model: y = a+bx+cx2) were calculated simultaneously. Morphological variables are a significantly better predictor of the FS50 in males (BH mostly), and FS400 in females (BW mostly). This study emphasized some of the main advantages in the nonlinear regression calculation (including an interpretation of the relationships at a more superior level), and consequently allowed a precise anthropometric modeling in swimming using simple and easily measurable variables. For example, the best results in FS400 can be expected for the subjects that are average in BW (which guarantees solid muscle mass--the generator of force), but above average in BH (because of the physical law of lever). In conclusion, nonlinear regressions allow one to define the real nature of the relationships between variables, but only if compared with the linear ones. Additionally, this study emphasized one of the most important factors in defining possible specification-equation (e.g. structure of the influence of the different dimensions on the sport achievement) in different sports. In short, it underlines the importance of sampling the appropriate sample of the subject--highly skilled athletes exclusively.     

Decomposition of tensiomyogram and comparison with torque twitch responses after post-activation potentiation

Objectives:This study evaluates the effect of post-activation potentiation (PAP) after 5x5s maximal voluntary isometric contractions (activation stimulus, AS) on tensiomyography (TMG) and torque twitch contractile parameters of vastus lateralis (VL) and medialis (VM), respectively. Further, we validated the decomposition of TMG response to separate responses of three fiber types.Methods:15 healthy individuals participated in this study (40% women; age 19±2.3 years). A decomposition of VL TMG response was done after optimal fitting of three exponential curves.Results:We found main effects in contraction time (Tc) for muscle, method and time. Furthermore, we found interactions between muscle*method, method*time and muscle*method*time. Compared to PRE AS, we found shorter TMG Tc in VL and VM during the first two minutes after AS. Torque Tc remained unchanged in VL, while it increased in VM within 30 seconds after AS. A decomposition of VL TMG response confirmed PAP effects being present only in decomposed type IIb muscle fibers.Conclusion:The TMG is a sensitive method to detect PAP effects with a sensor mounted directly above the muscle belly. After the decomposition of the TMG signal to three separate muscle fiber phenotypes, we provided a non-invasive insight in the contribution of each muscle fiber phenotype to the PAP of the whole muscle.     

Cholesterol-depletion corrects APP and BACE1 misstrafficking in NPC1-deficient cells

Cholesterol accumulation in Niemann-Pick type C disease (NPC) causes increased levels of the amyloid-precursor-protein C-terminal fragments (APP-CTFs) and intracellular amyloid-β peptide (Aβ), the two central molecules in Alzheimer's disease (AD) pathogenesis. We previously reported that cholesterol accumulation in NPC-cells leads to cholesterol-dependent increased APP processing by β-secretase (BACE1) and decreased APP expression at the cell surface (Malnar et al. Biochim Biophys Acta. 1802 (2010) 682-691.). We hypothesized that increased formation of APP-CTFs and Aβ in NPC disease is due to cholesterol-mediated altered endocytic trafficking of APP and/or BACE1. Here, we show that APP endocytosis is prerequisite for enhanced Aβ levels in NPC-cells. Moreover, we observed that NPC cells show cholesterol dependent sequestration and colocalization of APP and BACE1 within enlarged early/recycling endosomes which can lead to increased β-secretase processing of APP. We demonstrated that increased endocytic localization of APP in NPC-cells is likely due to both its increased internalization and its decreased recycling to the cell surface. Our findings suggest that increased cholesterol levels, such as in NPC disease and sporadic AD, may be the upstream effector that drives amyloidogenic APP processing characteristic for Alzheimer's disease by altering endocytic trafficking of APP and BACE1.     

Hybrid modeling approach to on-line estimation of yeast biomass concentration in industrial bioreactor

The industrial fed-batch yeast cultivation process has been divided into four different metabolic phases (adaptation, carbon limited, oxygen limited and maturation) by a neuro-fuzzy classification model that consists of 4 applied linguistic rules on 2 state variables: oxygen uptake rate and liquid volume. The membership functions have been automatically adapted by this fuzzy perceptron, i.e., by a supervised learning algorithm initialized by prior operator's knowledge. Process compartmentalization has made easier and more realistic a subsequent state estimation of the biomass concentration with separate artificial neural networks combined with balance equations. Static networks with local recurrent memory structures were used, and the inputs were standard cultivation state variables: respiratory quotient, molasses feed rate, ethanol concentration, etc. This hybrid approach is generally applicable to state estimation or prediction when different sources of process information and knowledge have to be integrated.     

Functions of multiple exonucleases are essential for cell viability, DNA repair and homologous recombination in recD mutants of Escherichia coli

Heterotrimeric RecBCD enzyme unwinds and resects a DNA duplex containing blunt double-stranded ends and directs loading of the strand-exchange protein RecA onto the unwound 3'-ending strand, thereby initiating the majority of recombination in wild-type Escherichia coli. When the enzyme lacks its RecD subunit, the resulting RecBC enzyme, active in recD mutants, is recombination proficient although it has only helicase and RecA loading activity and is not a nuclease. However, E. coli encodes for several other exonucleases that digest double-stranded and single-stranded DNA and thus might act in consort with the RecBC enzyme to efficiently promote recombination reactions. To test this hypothesis, I inactivated multiple exonucleases (i.e., exonuclease I, exonuclease X, exonuclease VII, RecJ, and SbcCD) in recD derivatives of the wild-type and nuclease-deficient recB1067 strain and assessed the ability of the resultant mutants to maintain cell viability and to promote DNA repair and homologous recombination. A complex pattern of overlapping and sometimes competing activities of multiple exonucleases in recD mutants was thus revealed. These exonucleases were shown to be essential for cell viability, DNA repair (of UV- and gamma-induced lesions), and homologous recombination (during Hfr conjugation and P1 transduction), which are dependent on the RecBC enzyme. A model for donor DNA processing in recD transconjugants and transductants was proposed.     

Exonuclease requirements for recombination of lambda-phage in recD mutants of Escherichia coli

Recombination of lambda red gam phage in recD mutants is unaffected by inactivation of RecJ exonuclease. Since nucleases play redundant roles in E. coli, we inactivated several exonucleases in a recD mutant and discovered that 5'-3' exonuclease activity of RecJ and exonuclease VII is essential for lambda-recombination, whereas exonucleases of 3'-5' polarity are dispensable. The implications of the presented data on current models for recombination initiation in E. coli are discussed.     

Therapeutic efficacy of 5% NaCl hypertonic solution in patients with bullous keratopathy

A clinical trial was undertaken to evaluate the efficacy of hypertonic solution (5% NaCl) in patients who have bullous keratopathy (BK). The aim of the study was to define the stage of the disease and the thickness of cornea in micrometers, which would be the threshold for therapeutic approach. This was a prospective study on 70 eyes of 55 patients. Patients were divided in two groups at the beginning of the study. The first group (n=33 eyes) included patients with initial stage of BK: only stromal component of corneal oedema was present. The second group (n=37 eyes) included patients with advanced stage of BK: the epithelial component of the disease with bullae on the corneal surface had already developed. Visual acuity, central and peripheral thickness of cornea and morphology of the disease was recorded before therapy, 7 days and 4 weeks after administration of hypertonic solution. Our results shown that the efficacy of hypertonic solution correlates with the severity of clinical picture in patients with BK. When 5% NaCl hypertonic solution was applied in the early stage of the disease, when only stromal component of corneal oedema was presented, visual acuity and pachymetry readings were significantly improved. The threshold pachymerty measurement of corneal thickness justifying the application of hypertonic solution was 613-694 microm (in the central corneal area), and 633-728 microm (at corneal periphery). It seems reasonable to apply hypertonic solution to the patients who have BK and whose pachymetric values are below mentioned range. In terminal stages of BK, when superficial bullae (epithelial component) had already developed, treatment with NaCl was not effective and patients had to be submitted to penetrating keratoplasty.     

Laparoscopic abdominal cysts fenestration using harmonic scalpel

The use of ultrasonically activated scalpel for tissue cutting and coagulation is a potential replacement for electrosurgery, which can be related to different complications. Its working principle is to transform the electric power into the mechanical longitudinal movement of the working part of the instrument, by a piezoelectric transducer situated in the hand piece. Between October 2000 and June 2004, six patients with abdominal cysts were treated by laparoscopy, using the harmonic scalpel. The average age was 40.8 (ranging from 15-60) years. Laparoscopic abdominal cyst fenestration was performed in five patients, and laparoscopic cholecystectomy and abdominal cyst fenestration were done in one patient during the same operation. The average duration of the operation was 40 (ranging from 25-70) minutes and hospital stay was 2.8 (ranging from 1-5) days. Laparoscopic abdominal cyst fenestration using the harmonic scalpel is a safe and successful operation, with good results including all the advantages of the minimally invasive surgery.