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Lumbrical Muscles Neural Branching Patterns: A Cadaveric Study With Potential Clinical Implications.Hand (New York, N.Y.) Sep 2022Lumbrical muscles originate in the palm from the 4 tendons of the flexor digitorum profundus and course distally along the radial side of the corresponding...
BACKGROUND
Lumbrical muscles originate in the palm from the 4 tendons of the flexor digitorum profundus and course distally along the radial side of the corresponding metacarpophalangeal joints, in front of the deep transverse metacarpal ligament. The first and second lumbrical muscles are typically innervated by the median nerve, and third and fourth by the ulnar nerve. A plethora of lumbrical muscle variants has been described, ranging from muscles' absence to reduction in their number or presence of accessory slips. The current cadaveric study highlights typical and variable neural supply of lumbrical muscles.
MATERIALS
Eight (3 right and 5 left) fresh frozen cadaveric hands of 3 males and 5 females of unknown age were dissected. From the palmar wrist crease, the median and ulnar nerve followed distally to their terminal branches. The ulnar nerve deep branch was dissected and lumbrical muscle innervation patterns were noted.
RESULTS
The frequency of typical innervations of lumbrical muscles is confirmed. The second lumbrical nerve had a double composition from both the median and ulnar nerves, in 12.5% of the hands. The thickest branch (1.38 mm) originated from the ulnar nerve and supplied the third lumbrical muscle, and the thinnest one (0.67 mm) from the ulnar nerve and supplied the fourth lumbrical muscle. In 54.5%, lumbrical nerve bifurcation was identified.
CONCLUSION
The complex innervation pattern and the peculiar anatomy of branching to different thirds of the muscle bellies are pointed out. These findings are important in dealing with complex and deep injuries in the palmar region, including transmetacarpal amputations.
Topics: Cadaver; Female; Hand; Humans; Male; Median Nerve; Muscle, Skeletal; Ulnar Nerve
PubMed: 33349041
DOI: 10.1177/1558944720963881 -
Turkish Neurosurgery 2017The middle cerebral artery (MCA) covers a large part of the cerebral hemispheres and is therefore exposed during surgical intervention in this area. Aspects of cerebral... (Review)
Review
The middle cerebral artery (MCA) covers a large part of the cerebral hemispheres and is therefore exposed during surgical intervention in this area. Aspects of cerebral branches tend to vary, different branching patterns can be described, and several anomalies can be observed. Knowledge of these variations and anomalies is important and can be helpful to neurosurgeons and clinicians. The aim of this manuscript was to review the available literature on the cortical branches, branching pattern and anomalies of the MCA, to identify the gaps in the literature, and to fill these gaps by including the results of a pilot study. Twenty hemispheres were perfused with colored silicone and the MCA was dissected. For the cortical branches, the diameter, length, presence, duplication and origins were noted. Most commonly duplicated was the anterior parietal artery in 30.0%, and most commonly absent was the common temporal artery in 65.0%. A detailed description on the origins is given. Criteria were described for the bifurcation subtypes and medial bifurcation (50.0%) was most commonly observed. No anomalies were observed. Aspects previously neglected of the MCA cortical branches were reported in the pilot study. The branching subtypes were identified and criteria are given. Illustrations of the different branching subtypes and anomalies are provided. Certain aspects of the MCA anatomy have been neglected, and future studies should give adequate descriptions of the MCA cortical branches, MCA branching pattern, and any anomalies observed.
Topics: Humans; Middle Cerebral Artery; Temporal Arteries
PubMed: 27593841
DOI: 10.5137/1019-5149.JTN.18127-16.1 -
Biomaterials Apr 2019The intricate architecture of branched tissues and organs has fascinated scientists and engineers for centuries. Yet-despite their ubiquity-the biophysical and... (Review)
Review
The intricate architecture of branched tissues and organs has fascinated scientists and engineers for centuries. Yet-despite their ubiquity-the biophysical and biochemical mechanisms by which tissues and organs undergo branching morphogenesis remain unclear. With the advent of three-dimensional (3D) culture models, an increasingly powerful and diverse set of tools are available for investigating the development and remodeling of branched tissues and organs. In this review, we discuss the application of 3D culture models for studying branching morphogenesis of the mammary gland and the mammalian lung in the context of normal development and disease. While current 3D culture models lack the cellular and molecular complexity observed in vivo, we emphasize how these models can be used to answer targeted questions about branching morphogenesis. We highlight the specific advantages and limitations of using 3D culture models to study the dynamics and mechanisms of branching in the mammary gland and mammalian lung. Finally, we discuss potential directions for future research and propose strategies for engineering the next generation of 3D culture models for studying tissue morphogenesis.
Topics: Animals; Equipment Design; Humans; Lab-On-A-Chip Devices; Lung; Mammary Glands, Human; Morphogenesis; Organ Culture Techniques; Organoids; Tissue Engineering
PubMed: 30174198
DOI: 10.1016/j.biomaterials.2018.08.043 -
Nanomaterials (Basel, Switzerland) Apr 2021One dimensional titanium nanorod structures formed by glancing angle physical vapor deposition have branches while other hexagonal closed packed metals do not. Based on...
One dimensional titanium nanorod structures formed by glancing angle physical vapor deposition have branches while other hexagonal closed packed metals do not. Based on physical vapor deposition and characterizations using electron microscopy and X-ray diffraction, this paper reports that Ti nanorod branching occurs at a low homologous temperature of 0.28. The side surface of the nanorods consists of {101¯1} facets arranged in a zigzag shape. Further, branches form on the {101¯1} side facets that are parallel to the deposition flux. The length of the branches increases as they are farther away from the nanorod top and tend to reach a constant. The top surface facet of Ti nanorods is {0001} and that of the branches is {101¯1}. The insight into conditions for branching, together with the determination of the morphology and crystal orientation of the branches, lay the foundation for further studies of branching mechanisms and driving force.
PubMed: 33921936
DOI: 10.3390/nano11051070 -
Physics of Fluids (Woodbury, N.Y. :... Jun 2017A major aim of the present work is to understand and thoroughly document the generation, the three-dimensional distribution, and the evolution of the secondary motion as...
A major aim of the present work is to understand and thoroughly document the generation, the three-dimensional distribution, and the evolution of the secondary motion as the fluid progresses downstream through a branched network. Six generations (G0-G5) of branches (involving 63 straight portions and 31 bifurcation modules) are computed in one go; such computational challenges are rarely taken in the literature. More than 30 × 10 computational elements are employed for high precision of computed results and fine quality of the flow visualization diagrams. The study of co-planar vis-à-vis non-planar space-filling configurations establishes a quantitative evaluation of the dependence of the fluid dynamics on the three-dimensional arrangement of the same individual branches. As compared to the secondary motion in a simple curved pipe, three distinctive features, viz., the change of shape and size of the flow-cross-section, the division of non-uniform primary flow in a bifurcation module, and repeated switchover from clockwise to anticlockwise curvature and vice versa in the flow path, make the present situation more complex. It is shown that the straight portions in the network, in general, attenuate the secondary motion, while the three-dimensionally complex bifurcation modules generate secondary motion and may alter the number, arrangement, and structure of vortices. A comprehensive picture of the evolution of quantitative flow visualizations of the secondary motion is achieved by constructing contours of secondary velocity [Formula: see text], streamwise vorticity [Formula: see text], and [Formula: see text] iso-surfaces. It is demonstrated, for example, that for in-plane configuration, the vortices on any plane appear in pair (i.e., for each clockwise rotating vortex, there is an otherwise identical anticlockwise vortex), whereas the vortices on a plane for the out-of-plane configuration may be dissimilar, and there may even be an odd number of vortices. We have formulated three new parameters ( , [Formula: see text], and [Formula: see text]) for a quantitative description of the overall features of the secondary flow field. [Formula: see text] represents a non-uniformity index of the secondary flow in an individual branch, represents the mass-flow-averaged relative kinetic energy of the secondary motion in an individual branch, and [Formula: see text] provides a measure of the non-uniformity of the secondary flow between various branches of the same generation . The repeated enhancement of the secondary kinetic energy in the bifurcation modules is responsible for the occurrence of significant values of even in generation G5. For both configurations, it is found that for any bifurcation module, the value of is greater in that daughter branch in which the mass-flow rate is greater. Even though the various contour plots of the complex secondary flow structure appear visually very different from one another, the values of [Formula: see text] are found to lie within a small range ([Formula: see text]) for the six-generation networks studied. It is shown that [Formula: see text] grows as the generation number increases. It is established that the out-of-plane configuration, in general, creates more secondary kinetic energy (higher ), a similar level of non-uniformity in the secondary flow in an individual branch (similar [Formula: see text]), and a significantly lower level of non-uniformity in the distribution of secondary motion among various branches of the same generation (much lower [Formula: see text]), as compared to the in-plane arrangement of the same branches.
PubMed: 28713213
DOI: 10.1063/1.4984919 -
Plant Biotechnology Journal Sep 2021Branching determines cotton architecture and production, but the underlying regulatory mechanisms remain unclear. Here, we report that the miR164-GhCUC2 (CUP-SHAPED...
Branching determines cotton architecture and production, but the underlying regulatory mechanisms remain unclear. Here, we report that the miR164-GhCUC2 (CUP-SHAPED COTYLEDON2) module regulates lateral shoot development in cotton and Arabidopsis. We generated OE-GhCUC2m (overexpression GhCUC2m) and STTM164 (short tandem target mimic RNA of miR164) lines in cotton and heterologous expression lines for gh-miR164, GhCUC2 and GhCUC2m in Arabidopsis to study the mechanisms controlling lateral branching. GhCUC2m overexpression resulted in a short-branch phenotype similar to STTM164. In addition, heterologous expression of GhCUC2m led to decreased number and length of branches compared with wild type, opposite to the effects of the OE-gh-pre164 line in Arabidopsis. GhCUC2 interacted with GhBRC1 and exhibited similar negative regulation of branching. Overexpression of GhBRC1 in the brc1-2 mutant partially rescued the mutant phenotype and decreased branch number. GhBRC1 directly bound to the NCED1 promoter and activated its transcription, leading to local abscisic acid (ABA) accumulation and response. Mutation of the NCED1 promoter disrupted activation by GhBRC1. This finding demonstrates a direct relationship between BRC1 and ABA signalling and places ABA downstream of BRC1 in the control of branching development. The miR164-GhCUC2-GhBRC1-GhNCED1 module provides a clear regulatory axis for ABA signalling to control plant architecture.
Topics: Abscisic Acid; Gene Expression Regulation, Plant; Gossypium; MicroRNAs; Plant Proteins; Transcription Factors
PubMed: 33960609
DOI: 10.1111/pbi.13599 -
Frontiers in Physiology 2022Branching morphogenesis is the process that gives rise to branched structures in several organs, such as the lung, the kidney, and the mammary gland. Although...
Branching morphogenesis is the process that gives rise to branched structures in several organs, such as the lung, the kidney, and the mammary gland. Although morphologically well described, the exact mechanisms driving branch elongation and bifurcation are still poorly understood. Signaling cues from the stroma and extracellular matrix have an important role in driving branching morphogenesis. Organoid models derived from primary mammary epithelial cells have emerged as a powerful tool to gain insight into branching morphogenesis of the mammary gland. However, current available mammary organoid culture protocols result in morphologically simple structures which do not resemble the complex branched structure of the mammary gland. Supplementation of growth factors to mammary organoids cultured in basement membrane extract or collagen I were shown to induce bud formation and elongation but are not sufficient to drive true branching events. Here, we present an improved culture approach based on 3D primary mammary epithelial cell culture to develop branched organoids with a complex morphology. By alternating the addition of fibroblast growth factor 2 and epidermal growth factor to mammary organoids cultured in a basement membrane extract matrix enriched with collagen type I fibers, we obtain complex mammary organoid structures with primary, secondary, and tertiary branches over a period of 15-20 days. Mammary organoid structures grow >1 mm in size and show an elongated and branched shape which resembles mammary gland morphology. This novel branched mammary organoid model offers many possibilities to study the mechanisms of branching in the developing mammary gland.
PubMed: 35399282
DOI: 10.3389/fphys.2022.826107 -
International Journal For Numerical... Nov 2022We report a computational study of mitochondria transport in a branched axon with two branches of different sizes. For comparison, we also investigate mitochondria...
We report a computational study of mitochondria transport in a branched axon with two branches of different sizes. For comparison, we also investigate mitochondria transport in an axon with symmetric branches and in a straight (unbranched) axon. The interest in understanding mitochondria transport in branched axons is motivated by the large size of arbors of dopaminergic neurons, which die in Parkinson's disease. Since the failure of energy supply of multiple demand sites located in various axonal branches may be a possible reason for the death of these neurons, we were interested in investigating how branching affects mitochondria transport. Besides investigating mitochondria fluxes between the demand sites and mitochondria concentrations, we also studied how the mean age of mitochondria and mitochondria age densities depend on the distance from the soma. We established that if the axon splits into two branches of unequal length, the mean ages of mitochondria and age density distributions in the demand sites are affected by how the mitochondria flux splits at the branching junction (what portion of mitochondria enter the shorter branch and what portion enter the longer branch). However, if the axon splits into two branches of equal length, the mean ages and age densities of mitochondria are independent of how the mitochondria flux splits at the branching junction. This even holds for the case when all mitochondria enter one branch, which is equivalent to a straight axon. Because the mitochondrial membrane potential (which many researchers view as a proxy for mitochondrial health) decreases with mitochondria age, the independence of mitochondria age on whether the axon is symmetrically branched or straight (providing the two axons are of the same length), and on how the mitochondria flux splits at the branching junction, may explain how dopaminergic neurons can sustain very large arbors and still maintain mitochondrial health across branch extremities.
Topics: Neurons; Axons; Mitochondria
PubMed: 36125402
DOI: 10.1002/cnm.3648 -
In Vivo (Athens, Greece) 2022Animals differ in the biochemical composition, attachments, and mechanical properties of tracheal cartilage. This study examined the biomechanical properties and...
BACKGROUND/AIM
Animals differ in the biochemical composition, attachments, and mechanical properties of tracheal cartilage. This study examined the biomechanical properties and morphological structure of the trachea of pigs, and rabbits as preclinical models.
MATERIALS AND METHODS
The trachea in pigs and rabbits can be divided into four regions, cranial cervical, middle cervical, thoracic inlet, and intra-thoracic parts.
RESULTS
The total number of tracheal rings in pigs and rabbits was 32-35 and 34-38 rings, respectively. The pig bronchus first branches from the trachea, reaching the cranial lobe of the lungs before branching to the main bronchus, while the rabbit bronchus branched after the main bronchus. A comparison of the posterior region of the crosssectional trachea shows that the rabbit has a C-shape with cartilage connected to the tracheal muscle, and the pig has the tracheal muscle covered with cartilage. The trachea of pigs and rabbits decreased in tracheal thickness and size from the thoracic inlet toward the lungs. The stress-strain in the longitudinal and transverse tensile test was higher in rabbits than in pigs. The tensile stress of the four regions was significantly different in the transverse tensile test (p<0.001). In the bending test, more force was required to bend pig than rabbit tracheas. Microscopic and scanning electron microscopy showed no structural differences in tracheal cartilage between the two species.
CONCLUSION
These results suggest that there is great variation in morphology and physical properties of the trachea in pigs and rabbits. We found porcine tracheas have similar biomechanical properties to those of humans.
Topics: Animals; Cartilage; Rabbits; Swine; Trachea
PubMed: 35738586
DOI: 10.21873/invivo.12884 -
Journal of Anatomy Dec 2021The anterolateral thigh flap and the tensor fasciae latae flap are supplied by the lateral circumflex femoral artery (LCFA). Different branching patterns of the LCFA...
The anterolateral thigh flap and the tensor fasciae latae flap are supplied by the lateral circumflex femoral artery (LCFA). Different branching patterns of the LCFA have been described, leading to confusion, discrepancies and difficulties in clinical and cadaveric study comparisons. The aim of this study was to evaluate the branching patterns of the LCFA in dissected lower limbs and propose a simplified nomenclature. One hundred and two lower limbs fixed with Thiel's method were investigated. Meticulous dissection was performed, and the branching pattern of the arteries was documented by illustration and photography. These were analysed and allocated to the currently existing terminologies regarding the numbers of the branches (Part 1), and these subgroups were evaluated according to the variability of the trunk formations (Part 2). In Part 1, four subgroups could be classified (A, B, C and D). Group A included a total number of three branches (n = 50), Group B included four (n = 41), Group C included five (n = 5) and Group D included only two branches (n = 6). Part 2 showed in total 11 different trunk variations. Group A had four trunk variations: A1 (n = 38), A2 (n = 5), A3 (n = 2) and A4 (n = 6); Group B also had four variations: B1 (n = 16), B2 (n = 18), B3 (n = 3) and B4 (n = 4); Group C displayed two variations: C1 (n = 1) and C2 (n = 4); and in Group D, there was only one variation observed D1 (n = 6). Branching patterns were highly variable and inconsistent in terms of the number of branches and trunk variations, which resulted in different possible and justified interpretations and classifications. A new terminology should be defined cooperatively among anatomists and clinicians that will be useful for everybody. We propose a terminology oriented to the associated muscles.
Topics: Femoral Artery; Humans; Lower Extremity; Muscles; Surgical Flaps; Thigh
PubMed: 34310710
DOI: 10.1111/joa.13507