First-order thalamic nuclei receive driving afferents from ascending pathways and transmit processed information to the cortex. Higher-order thalamic nuclei receive driver messages from layer 5 of cortex and transmit information from one cortical area to the other. The different types of axon terminals RL (round vesicles, large terminals), RS (round vesicles, small terminals) and F (flattened vesicles) and their synaptic junctions have been here compared in three first-order (ventrobasal, lateral geniculate and anteroventral) and three higher-order (posterior, lateral posterior and mediodorsal) thalamic nuclei of the rat. In the present study, the higher-order relays differ from first-order relays as in the cat, in having fewer driver terminals (RL) and synapses than do the first-order relays. However, the F terminals showed opposite ratios in the first versus higher-order thalamic nuclei. The majority of the terminals in all thalamic nuclei studied were RS terminals. The area measurements of the three types of terminals and synaptic lengths showed no significant differences between first and higher-order nuclei. The driver inputs represent the minority and the modulatory inputs represent the majority of the terminals and synapses in all thalamic nuclei. In conclusion, there is a relative paucity of driver inputs, whereas modulatory inputs establish more numerous synapses to achieve finer modulation.
Background. The aim of the study was to evaluate whether or not there was any incompatibility between four-strand hamstring tendons taken from the same knee and the dimensions of the ACL and PCL. Methods. 15 fresh frozen cadaver hamstrings were prepared as four-strand grafts and measurements made of the ACL and PCL circumferences in the midsection were made in the narrowest part of the midsection. The cross-section areas and diameters were calculated with geometric calculations used to measure the cross-sectional area of cylinders. Accepting that the geometric insertions were elliptical, the length, width, and area were calculated for entry areas. Results. A significant relationship at 96.2% was determined between the ACL mid and the hamstring diameter. A significant relationship at 96.7% was determined between the ACL and the hamstring mid area. A significant relationship at 96.4% was determined between the PCL mid and the hamstring diameter. A significant relationship at 95.7% was determined between the PCL and the hamstring mid area. Conclusion. For the reconstruction of ACL and PCL, it was determined that there is less incompatibility between the four-strand hamstring tendons taken from the same knee and the dimensions of the midsection PCL compared to the ACL dimensions.
SALBACAK, A.; AKIN, D.; KABAKCI, A. D. A.; YILMAZ, M. T.; CICEKCIBASI, A. E. & OZBEK, O.Morphometric analysis of the inferior vena cava related to the lumbar vertebra and the aortic bifurcation on multidetector computed tomography (MDCT). Int. J. Morphol., 34(2):620-627, 2016. SUMMARY:Vascular structures are in greater danger during lumbar surgery. The purpose of this study is to describe the morphology of the inferior vena cava (IVC) related to the lumbar vertebra and aortic bifurcation (AB) and assessing the role of demographic values in these relations to decrease the risk of complications in the surgical interventions. The study was performed on Multidetector Computed Tomography (MDCT) images of 100 male and 100 female cases with an age range from 50 to 84 years. The morphometric values of the IVC obtained from the coronal, sagittal and the axial reformatted images were measured and compared with the demographic values. The distance from the IVC to the 1 st lumbar vertebra (L1) and 2 nd lumbar vertebra (L2) were measured as (26.5 mm and 18.1 mm) in males and (21.1 mm and 14.2 mm) in females with a high level of significance between genders; the distance from the IVC to the iliocaval confluence (IC), 3 rd lumbar vertebra (L3) and 4 rd lumbar vertebra (L4) were measured as (6.5 mm, 10.5 mm and 6.9 mm) in males and (4.9 mm, 9.1 mm and 5.5 mm) in females with significance between genders. The level of the IC was detected 46 % of males, 39 % of females at the level of lower third of L4. The vertical distance between the IC and the AB was measured and negative correlation between genders based on age was detected. Demographic values are important to consider the relationship of the IVC, the lumbar vertebra and the AB. The IVC was located further from the lumbar vertebra in males compared to females. Age increase played role in the approaching of the AB and the IC to each other in both gender and the IC to the promontory level in males.
METHODS: RESULTS: CONCLUSIONS.
Ventroposterior medialis parvocellularis (VPMP) nucleus of the primate thalamus receives direct input from the nucleus of the solitary tract, whereas the homologous thalamic structure in the rodent does not. To reveal whether the synaptic circuitries in these nuclei lend evidence for conservation of design principles in the taste thalamus across species or across sensory thalamus in general, we characterized the ultrastructural and molecular properties of the VPMP in a close relative of primates, the tree shrew (Tupaia belangeri), and compared these to known properties of the taste thalamus in rodent, and the visual thalamus in mammals. Electron microscopy analysis to categorize the synaptic inputs in the VPMP revealed that the largest‐size terminals contained many vesicles and formed large synaptic zones with thick postsynaptic density on multiple, medium‐caliber dendrite segments. Some formed triads within glomerular arrangements. Smaller‐sized terminals contained dark mitochondria; most formed a single asymmetric or symmetric synapse on small‐diameter dendrites. Immuno‐EM experiments revealed that the large‐size terminals contained VGLUT2, whereas the small‐size terminal populations contained VGLUT1 or ChAT. These findings provide evidence that the morphological and molecular characteristics of synaptic circuitry in the tree shrew VPMP are similar to that in nonchemical sensory thalamic nuclei. Furthermore, the results indicate that all primary sensory nuclei of the thalamus in higher mammals share a structural template for processing thalamocortical sensory information. In contrast, substantial morphological and molecular differences in rodent versus tree shrew taste nuclei suggest a fundamental divergence in cellular processing mechanisms of taste input in these two species.
Background:Hair shaft diameter is one of the most important factors for the outcome of follicular unit extraction (FUE) surgery. In fact, the hair shaft is elliptical. Therefore, it has a long and short axis. Many hair transplantation surgeons use manual micrometer caliper for gauging hair diameter and use the results in the management of recipient and donor area. Aim:In this study, we aimed to identify the dependability of micrometer caliper and also the hair diameter diversity pattern in the donor area.Patients/Methods: Two hundred and seventy hairs were collected from three males with androgenetic alopecia. Hair samples were obtained from the 1 cm 2 boxes from superior to inferior at the mid-point of temporal, parietal, and occipital donor areas.The diameter of each hair was measured both with a micrometer caliper and scanning electron microscopy (SEM).Results: Average diameter measured by scanning electron microscopy was 83.01 µm for the long axis and 51.51 µm for the short axis. The average value for the micrometer caliper measurement was 53.32 µm. Comparison of micrometer caliper results with the short-axis measurements of SEM revealed a strong significant correlation.The hair diameters from superior, middle, and inferior boxes revealed a tendency to decrease toward the inferior regions. Conclusions:A manual micrometer caliper is a dependable tool for planning FUE surgery, and it measures the short axis of the elliptical hair shaft. Hair diameter tends to decrease toward the inferior regions of the donor area. K E Y W O R D S caliper micrometer, hair diameter, hair transplantation, scanning electron microscopy | 1087 Region N Micrometer caliper SEM short axis SEM long axis Mean ± SD, Median (range) Overall 270 53.4 ± 7.8 53.0 (34.0-82.0) 51.5 ± 8.3 50.6 (29.9-82.0) 83.0 ± 12.2 83.3 (49.0-112.1) Occipital 90 52.4 ± 7.1 52.
Background: EFECE systems are newly defined internal fixation systems, which are suitable for patella fracture fixation. The aim of this study was to compare the fixation strength of EFECE Systems with tension band wiring for transverse patellar fracture simulation on fresh frozen cadaver models. Methods: Quadriceps tendon-patella-patellar tendon (QT-P-PT) complex was prepared from human cadavers. After simulation of a transverse patella fracture, in group 1, 5 patella were fixed with a pair of 1.2 mm EFECE wires and 4 EFECE devices. In group 2, 5 patella were fixed with a pair of 1.2 mm Kirschner wires (K-wire) and a cerclage wire according to the tension band technique. Using a testing device with custom-made jaws, increasing distraction force was applied to these QT-P-PT complexes. Extension of these complexes with the distraction forces was observed. The maximum distraction force and the elongation during maximum force were evaluated. Results: After 5 experiments with the EFECE systems, there was no EFECE wire breakage or EFECE wire-EFECE device catching failure. The median maximum force was 740 N (720-810 N). During maximum distraction force the median extension was 2.5 mm (1.6-2.5 mm). After 5 experiments with the tension band technique, there was no Kwire breakage. The median maximum force was 330 N (240-510 N). During this maximum distraction force the median extension was 3.4 mm (2.2-3.8 mm). Conclusions: Based on the biomechanical advantages, patella fracture treatment with EFECE systems may constitute a reasonable alternative in the treatment of patella fractures.
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