Fis1, Mff,MiD49, and MiD51 mediate Drp1 recruitment in mitochondrial fission

Several mitochondrial outer membrane proteins—mitochondrial fission protein 1 (Fis1), mitochondrial fission factor (Mff), mitochondrial dynamics proteins of 49 and 51 kDa (MiD49 and MiD51, respectively)—have been proposed to promote mitochondrial fission by recruiting the GTPase dynamin-related protein 1 (Drp1), but fundamental issues remain concerning their function. A recent study supported such a role for Mff but not for Fis1. In addition, it is unclear whether MiD49 and MiD51 activate or inhibit fission, because their overexpression causes extensive mitochondrial elongation. It is also unknown whether these proteins can act in the absence of one another to mediate fission. Using Fis1-null, Mff-null, and Fis1/Mff-null cells, we show that both Fis1 and Mff have roles in mitochondrial fission. Moreover, immunofluorescence analysis of Drp1 suggests that Fis1 and Mff are important for the number and size of Drp1 puncta on mitochondria. Finally, we find that either MiD49 or MiD51 can mediate Drp1 recruitment and mitochondrial fission in the absence of Fis1 and Mff. These results demonstrate that multiple receptors can recruit Drp1 to mediate mitochondrial fission.     

Optimization of RAPD‐PCR conditions in cattle

Abstract

Random Amplified Polymorphic DNA polymerase chain reaction (RAPD‐PCR) is a fast and easy way of identifying DNA polymorphisms generated from several regions of the genome. This could expedite the process of identifying informative polymorphic markers that may be linked to important genes controlling economic traits. In cattle, failure to obtain consistent amplification patterns in RAPD‐PCR has been a cause for concern. This has been attributed to the fact that decamer primers that are used in RAPD‐PCR reactions are likely to amplify regions of DNA where the primer‐template base pairing has some degree of mismatch and that these mismatches fail to repeat from reaction to reaction. This paper describes the use of tricine buffer along with changes in reaction components and thermal cycling conditions that has yielded consistent and reproducible RAPD‐PCR amplifications using single primers and double primer combinations on bovine DNA.     

Endogenous cardiac activity rhythms of continental slope Nephrops norvegicus (decapoda: nephropidae)

The endogenous cardiac activity rhythm of the Norway lobster Nephrops norvegicus was studied under constant conditions of darkness by means of a computer-aided monitoring system (CAPMON). Time series recordings of the heart rate (beats min^?1) were obtained from 47 adult males freshly collected from the continental slope (400–430?m) in the western Mediterranean. Periodogram analysis revealed the occurrence of circadian periodicity (of around 24?h) in most cases. A large percentage of animals showed significant ultradian periods (of around 12 and 18?h). The analysis of the circadian time series revealed the occurrence of peaks of heart rate activity during the expected night phase of the cycle. These results are discussed in relation to the emergence and locomotor activity rhythms of the species.     

Genetic characterization of Colombian Brahman cattle using microsatellites markers

Genetic structure and diversity of 3789 animals of the Brahman breed from 23 Colombian regions were assessed. Considering the Brahman Zebu cattle as a single population, the multilocus test based on the HW equilibrium, shows significant differences (P < 0.001). Genetic characterization made on the cattle population allowed to examine the genetic variability, calculating a H _o = 0.6621. Brahman population in Colombia was a small subdivision wthin populations (F _it = 0.045), a geographic subdivision almost non-existent or low differentiation (F _st = 0.003) and the F _is calculated (0.042) indicates no detriment to the variability in the population, despite the narrow mating takes place or there is a force that causes the variability is sustained without inbreeding actually affect the cattle population. The outcomes of multivariate analyses, Bayesian inferences and interindividual genetic distances suggested that there is no genetic sub-structure in the population, because of the high rate of animal migration among regions.     

Desulfurization of dibenzothiophene using the 4S enzymatic route: Influence of operational conditions on initial reaction rates

The influence of operational conditions (pH, temperature and oxygen transfer rate) on the initial reaction rates of the four reactions involved in the 4S biodesulfurization route of dibenzothiophenes (DBT) has been studied. The bioprocess was carried out using a genetically modified organism, Pseudomonas putida CECT 5279. The rates of the four reactions were calculated from the rates of production of different compounds involved in the 4S pathway, by matrix manipulation. The initial (zero time) reaction rates showed a slight dependence on oxygen transfer rate. Temperature and pH were optimal at 30°C and 9, respectively, temperature being the most important variable. This study also identifies the last reaction as the limiting step in the pathway.     

A kinematic method for computing the motion of the body centre-of-mass (CoM) during walking: a Bayesian approach

The gait pattern of a particular patient can be altered in a large set of pathologies. Tracking the body centre-of-mass (CoM) during the gait allows a quantitative evaluation of these diseases at comparing the gait with normal patterns. A correct estimation of this variable is still an open question because of its non-linearity and inaccurate location. This paper presents a novel strategy for tracking the CoM, using a biomechanical gait model whose parameters are determined by a Bayesian strategy. A particle filter is herein implemented for predicting the model parameters from a set of markers located at the sacral zone. The present approach is compared with other conventional tracking methods and decreases the calculated root mean squared error in about a 56% in the x-axis and 59% in the y-axis.     

Simulation and study of the geometric parameters in the inguinal area and the genesis of inguinal hernias

We are interested in studying the genesis of a very common pathology: the human inguinal hernia. How the human inguinal hernia appears is not definitively clear, but it is accepted that it is caused by a combination of mechanical and biochemical alterations, and that muscular simulation plays an important role in this. This study proposes a model to explain how some physical parameters affect the ability to simulate the region dynamically and how these parameters are involved in generating inguinal hernias. We are particularly interested in understanding the mechanical alterations in the inguinal region because little is known about them or how they behave dynamically. Our model corroborates the most important theories regarding the generation of inguinal hernias and is an initial approach to numerically evaluating this affection.     

Finite element analysis of peri-implant bone volume affected by stresses around Morse taper implants: effects of implant positioning to the bone crest

Abstract

Objectives: The purpose of the present study was to evaluate the distribution and magnitude of stresses through the bone tissue surrounding Morse taper dental implants at different positioning relative to the bone crest. Materials and Methods: A mandibular bone model was obtained from a computed tomography scan. A three-dimensional (3D) model of Morse taper implant-abutment systems placed at the bone crest (equicrestal) and 2?mm bellow the bone crest (subcrestal) were assessed by finite element analysis (FEA). FEA was carried out on axial and oblique (45°) loading at 150 N relatively to the central axis of the implant. The von Mises stresses were analysed considering magnitude and volume of affected peri-implant bone. Results: On vertical loading, maximum von Mises stresses were recorded at 6-7?MPa for trabecular bone while values ranging from 73 up to 118?MPa were recorded for cortical bone. On oblique loading at the equiquestral or subcrestal positioning, the maximum von Mises stresses ranged from 15 to 21?MPa for trabecular bone while values at 150?MPa were recorded for the cortical bone. On vertical loading, >99.9vol.% cortical bone volume was subjected to a maximum of 2?MPa while von Mises stress values at 15?MPa were recorded for trabecular bone. On oblique loading, >99.9vol.% trabecular bone volume was subjected to maximum stress values at 5?MPa, while von Mises stress values at 35?MPa were recorded for >99.4vol.% cortical bone. Conclusions: Bone volume-based stress analysis revealed that most of the bone volume (>99% by vol) was subjected to significantly lower stress values around Morse taper implants placed at equicrestal or subcrestal positioning. Such analysis is commentary to the ordinary biomechanical assessment of dental implants concerning the stress distribution through peri-implant sites.