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Scientific Reports Oct 2023Irrespective of the exceptional adaptation of dromedaries to harsh environmental conditions, they remain highly susceptible to joint lameness resulting from a range of...
Irrespective of the exceptional adaptation of dromedaries to harsh environmental conditions, they remain highly susceptible to joint lameness resulting from a range of diverse factors and conditions. The joints most often affected by traumatic osteoarthritis in dromedaries are the metacarpophalangeal and metatarsophalangeal joints. A comprehensive understanding of joint anatomy and topography of the dromedary is required to perform arthrocentesis correctly on affected joints. Forty-two distal limbs were taken from 28 camels and studied by gross dissection, casting, ultrasonography, and computed tomography (CT). Representative three-dimensional models of the joint cavities, recesses, and pouches were obtained using different casting agents. This study provides a detailed description of dorsally, axially, and abaxially positioned joint recesses, as well as palmar/plantar positioned joint pouches. The safety and feasibility of the different arthrocentesis approaches were evaluated. The traditional dorsal arthrocentesis approach of the metacarpophalangeal, metatarsophalangeal, proximal interphalangeal, and distal interphalangeal joints, has limitations due to the risk of damaging the tendon structures and articular cartilage, which can lead to joint degeneration. A lateral arthrocentesis approach via the proximal palmar/plantar pouches of the metacarpophalangeal/metatarsophalangeal and proximal interphalangeal joints is recommended. This approach eliminates the potential needle injury to the articulating joint cartilage and other surrounding joint structures, such as tendons, blood vessels, and nerves.
Topics: Animals; Camelus; Arthrocentesis; Forelimb; Joints; Cartilage, Articular; Metatarsophalangeal Joint
PubMed: 37833397
DOI: 10.1038/s41598-023-44391-1 -
Stem Cell Reports May 2019The process of oligodendrogenesis has been relatively well delineated in the rodent brain. However, it remains unknown whether analogous developmental processes are...
The process of oligodendrogenesis has been relatively well delineated in the rodent brain. However, it remains unknown whether analogous developmental processes are manifested in the human brain. Here we report oligodendrogenesis in forebrain organoids, generated by using OLIG2-GFP knockin human pluripotent stem cell (hPSC) reporter lines. OLIG2/GFP exhibits distinct temporal expression patterns in ventral forebrain organoids (VFOs) versus dorsal forebrain organoids (DFOs). Interestingly, oligodendrogenesis can be induced in both VFOs and DFOs after neuronal maturation. Assembling VFOs and DFOs to generate fused forebrain organoids (FFOs) promotes oligodendroglia maturation. Furthermore, dorsally derived oligodendroglial cells outcompete ventrally derived oligodendroglia and become dominant in FFOs after long-term culture. Thus, our organoid models reveal human oligodendrogenesis with ventral and dorsal origins. These models will serve to study the phenotypic and functional differences between human ventrally and dorsally derived oligodendroglia and to reveal mechanisms of diseases associated with cortical myelin defects.
Topics: Cell Differentiation; Gene Expression Profiling; Green Fluorescent Proteins; Humans; Neural Stem Cells; Neurogenesis; Oligodendrocyte Transcription Factor 2; Oligodendroglia; Organoids; Pluripotent Stem Cells
PubMed: 31091434
DOI: 10.1016/j.stemcr.2019.04.011 -
Frontiers in Neuroscience 2015Although predator odors are ethologically relevant stimuli for rodents, the molecular pathways and contribution of some brain regions involved in predator odor...
Although predator odors are ethologically relevant stimuli for rodents, the molecular pathways and contribution of some brain regions involved in predator odor conditioning remain elusive. Inhibition of histone deacetylases (HDACs) in the dorsal hippocampus has been shown to enhance shock-induced contextual fear learning, but it is unknown if HDACs have differential effects along the dorso-ventral hippocampal axis during predator odor fear learning. We injected MS-275, a class I HDAC inhibitor, bilaterally in the dorsal or ventral hippocampus of mice and found that it had no effects on innate anxiety in either region. We then assessed the effects of MS-275 at different stages of fear learning along the longitudinal hippocampal axis. Animals were injected with MS-275 or vehicle after context pre-exposure (pre-conditioning injections), when a representation of the context is first formed, or after exposure to coyote urine (post-conditioning injections), when the context becomes associated with predator odor. When MS-275 was administered after context pre-exposure, dorsally injected animals showed enhanced fear in the training context but were able to discriminate it from a neutral environment. Conversely, ventrally injected animals did not display enhanced learning in the training context but generalized the fear response to a neutral context. However, when MS-275 was administered after conditioning, there were no differences between the MS-275 and vehicle control groups in either the dorsal or ventral hippocampus. Surprisingly, all groups displayed generalization to a neutral context, suggesting that predator odor exposure followed by a mild stressor such as restraint leads to fear generalization. These results may elucidate distinct functions of the dorsal and ventral hippocampus in predator odor-induced fear conditioning as well as some of the molecular mechanisms underlying fear generalization.
PubMed: 26441495
DOI: 10.3389/fnins.2015.00319 -
Plastic and Reconstructive Surgery Oct 2018Syndactyly reconstruction incorporates techniques of applying skin grafts or dorsal advancement flaps without the use of skin grafts. Comparative outcome studies of... (Comparative Study)
Comparative Study
BACKGROUND
Syndactyly reconstruction incorporates techniques of applying skin grafts or dorsal advancement flaps without the use of skin grafts. Comparative outcome studies of these two approaches are lacking. The authors' study compares the long-term aesthetic outcomes of these two flap techniques.
METHODS
Forty-five patients were included in the authors' study. The methods of reconstruction used were a dorsally based rectangular flap with skin graft from the groin and a dorsal pentagonal advancement flap without skin grafting. Eighteen independent raters completed a visual analogue scale and a unique classification scale to subjectively assess aesthetic outcomes. The authors used univariate analyses to determine which variables significantly influenced the outcome score. The authors then used multivariable regression models to compare the two flap types.
RESULTS
Dorsally based rectangular flaps with skin graft had statistically significantly better visual analogue scale scores and greater odds of receiving an "excellent" rating compared with dorsal pentagonal advancement flaps.
CONCLUSIONS
Despite the use of skin grafting, with its associated donor-site morbidity, dorsal rectangular flaps may offer better overall aesthetic outcomes for patients. Future comparative studies should incorporate functional and patient-reported outcomes to better assess the optimal reconstruction type.
CLINICAL QUESTION/LEVEL OF EVIDENCE
Therapeutic, III.
Topics: Child, Preschool; Esthetics; Female; Fingers; Humans; Infant; Male; Plastic Surgery Procedures; Reoperation; Retrospective Studies; Surgical Flaps; Syndactyly; Treatment Outcome
PubMed: 29994847
DOI: 10.1097/PRS.0000000000004798 -
Developmental Biology Mar 2007We have previously shown that retinoic acid (RA) synthesized by the retinaldehyde dehydrogenase 2 (RALDH2) is required in forebrain development. Deficiency in RA due to... (Comparative Study)
Comparative Study
We have previously shown that retinoic acid (RA) synthesized by the retinaldehyde dehydrogenase 2 (RALDH2) is required in forebrain development. Deficiency in RA due to inactivation of the mouse Raldh2 gene or to complete absence of retinoids in vitamin-A-deficient (VAD) quails, leads to abnormal morphogenesis of various forebrain derivatives. In this study we show that double Raldh2/Raldh3 mouse mutants have a more severe phenotype in the craniofacial region than single null mutants. In particular, the nasal processes are truncated and the eye abnormalities are exacerbated. It has been previously shown that retinoids act mainly on cell proliferation and survival in the ventral forebrain by regulating SHH and FGF8 signaling. Using the VAD quail model, which survives longer than the Raldh-deficient mouse embryos, we found that retinoids act in maintaining the correct position of anterior and dorsal boundaries in the forebrain by modulating FGF8 anteriorly and WNT signaling dorsally. Furthermore, BMP4 and FGF8 signaling are affected in the nasal region and BMP4 is ventrally expanded in the optic vesicle. At the optic cup stage, Pax6, Tbx5 and Bmp4 are ectopically expressed in the presumptive retinal pigmented epithelium (RPE), while Otx2 and Mitf are not induced, leading to a dorsal transdifferentiation of RPE to neural retina. Therefore, besides being required for survival of ventral structures, retinoids are involved in restricting anterior identity in the telencephalon and dorsal identity in the diencephalon and the retina.
Topics: Aldehyde Oxidoreductases; Animals; Bone Morphogenetic Protein 4; Bone Morphogenetic Proteins; Craniofacial Abnormalities; Fibroblast Growth Factor 8; Galactosides; Gene Expression Regulation, Developmental; In Situ Hybridization; In Situ Nick-End Labeling; Indoles; Mice; Mice, Mutant Strains; Microphthalmia-Associated Transcription Factor; Morphogenesis; Otx Transcription Factors; Prosencephalon; Quail; Retina; Retinal Dehydrogenase; Retinoids; Signal Transduction; T-Box Domain Proteins; Vitamin A Deficiency
PubMed: 17184764
DOI: 10.1016/j.ydbio.2006.11.021 -
International Journal of Surgery Case... 2014High energy distal radius fractures may cause significant soft tissue injuries. Dorsal displacement of median nerve and flexor tendons to dorsal compartment between...
INTRODUCTION
High energy distal radius fractures may cause significant soft tissue injuries. Dorsal displacement of median nerve and flexor tendons to dorsal compartment between distal radioulnar joint was an unreported type of soft tissue injury.
PRESENTATION OF CASE
35-Year male admitted following fall from height diagnosed as closed distal radius fracture with dorsal displacement. The patient had no flexion and extension of all fingers with loss of sensation. Radial artery pulse was not palpable. Radiography and CT imaging revealed distal radius fracture with dorsal displacement with dorsal carpal dislocation. After failure of closed reduction, operative treatment was performed. At surgery, flexor tendons and median nerve was found to be placed at dorsal compartment. Reduction of the soft tissues was facilitated by distraction of distal radioulnar joint.
DISCUSSION
Dorsal displacement of volar structures as the result of fracture dislocation was found to be an unreported type of injury. Difficulty during reduction of dorsally displaced structures is an important feature of the case.
CONCLUSION
For severely displaced and deformed distal radial fractures and fracture dislocations, threshold for operative treatment should be kept low.
PubMed: 25460459
DOI: 10.1016/j.ijscr.2014.10.076 -
Journal of Wrist Surgery Dec 2019This study aims to quantify the distances between the cortex of the distal radius and flexor and extensor tendons. We analyzed 50 magnetic resonance images (MRI)...
This study aims to quantify the distances between the cortex of the distal radius and flexor and extensor tendons. We analyzed 50 magnetic resonance images (MRI) of intact wrist without pathology. The distances between the volar cortex and the flexor pollicis longs (FPL), index flexor digitorum profunduns (FDPi), flexor digitorum profundus (FDP), and flexor digitorum superficialis (FDS) were measured at the level of the watershed line and 3- and 6-mm proximal to this level. The distances between the dorsal cortex and the extensor carpi radialis longus (ECRL), extensor carpi radialis brevis (ECRB), extensor pollicis longus (EPL), extensor indicis proprius (EIP), and the extensor digitorum communis (EDC) were measured at the level of Lister's tubercle and 5-mm distal to this level. Analysis was descriptive. At the watershed line, the FPL, FDPi, FDP, and FDS were located at an average of 3.1, 2.4, 3.6, and 5.1 mm, respectively, volar to the volar cortex. The distances of the FDP and FDS increased at 3-mm proximal to the watershed line and increased for all four tendons at 6-mm proximal to the watershed line. Dorsally, at Listers' tubercle the ECRL, ECRB, EPL, EIP, and EDC were identified at an average of 0.7, 0.5, 0.5, 2.6, and 3.2 mm, respectively, dorsal to the dorsal cortex of the distal radius. At 5-mm more distal, these tendons were located on average 1.2, 1.0, 0.7, 1.9, and 1.8 mm, respectively, dorsal to the dorsal cortex. On the volar side, on average there is enough room for a volar plate when staying proximal to the watershed line. On the dorsal side, there is virtually no room for protruding screws as physical anatomical space is limited to a maximum of 0.7 mm from cortex to the closest tendon (the FDP), with screw increments being 2 mm. This is a Level II Study.
PubMed: 31815061
DOI: 10.1055/s-0039-1693053 -
Anatomical Science International Sep 2023This study aimed to elucidate the origin, course, and distribution of the branches of the posterior femoral cutaneous nerve, considering the segmental and dorsoventral...
This study aimed to elucidate the origin, course, and distribution of the branches of the posterior femoral cutaneous nerve, considering the segmental and dorsoventral compositions of the sacral plexus, including the pudendal nerve. The buttocks and thighs of five cadavers were analyzed bilaterally. The branches emerged from the sacral plexus, which was divided dorsally to ventrally into the superior gluteal, inferior gluteal, common peroneal, tibial, and pudendal nerves. It descended lateral to the ischial tuberosity and comprised the thigh, gluteal, and perineal branches. As for the thigh and gluteal branches, the dorsoventral order of those originating from the sacral plexus corresponded to the lateromedial order of their distribution. However, the dorsoventral boundary was displaced at the inferior margin of the gluteus maximus between the thigh and gluteal branches. The perineal branch originated from the ventral branch of the nerve roots. In addition, the pudendal nerve branches, which ran medially to the ischial tuberosity, were distributed in the medial part of the inferior gluteal region. These branches should be distinguished from the gluteal branches; the former should be classified as the medial inferior cluneal nerves and the latter as the lateral ones. Finally, the medial part of the inferior gluteal region was distributed by branches of the dorsal sacral rami, which may correspond to the medial cluneal nerves. Thus, the composition of the posterior femoral cutaneous nerve is considered necessary when considering the dorsoventral relationships of the sacral plexus and boundaries of the dorsal and ventral rami.
Topics: Humans; Lumbosacral Plexus; Thigh; Muscle, Skeletal; Buttocks; Cadaver
PubMed: 37017904
DOI: 10.1007/s12565-023-00721-x -
World Journal of Orthopedics Jan 2014Hallux rigidus describes the osteoarthritis of the first metatarsophalangeal joint. It was first mentioned in 1887. Since then a multitude of terms have been introduced... (Review)
Review
Hallux rigidus describes the osteoarthritis of the first metatarsophalangeal joint. It was first mentioned in 1887. Since then a multitude of terms have been introduced referring to the same disease. The main complaints are pain especially during movement and a limited range of motion. Radiographically the typical signs of osteoarthritis can be observed starting at the dorsal portion of the joint. Numerous classifications make the comparison of the different studies difficult. If non-operative treatment fails to resolve the symptoms operative treatment is indicated. The most studied procedure with reproducible results is the arthrodesis. Nevertheless, many patients refuse this treatment option, favouring a procedure preserving motion. Different motion preserving and joint sacrificing operations such as arthroplasty are available. In this review we focus on motion and joint preserving procedures. Numerous joint preserving osteotomies have been described. Most of them try to relocate the viable plantar cartilage more dorsally, to decompress the joint and to increase dorsiflexion of the first metatarsal bone. Multiple studies are available investigating these procedures. Most of them suffer from low quality, short follow up and small patient numbers. Consequently the grade of recommendation is low. Nonetheless, joint preserving procedures are appealing because if they fail to relief the symptoms an arthrodesis or arthroplasty can still be performed thereafter.
PubMed: 24649409
DOI: 10.5312/wjo.v5.i1.6 -
Journal of Neuropathology and... Jan 2019Inflammatory processes may contribute to psychiatric disorders and suicide. Earlier, we reported greater densities of perivascular phagocytes in dorsal prefrontal white...
Inflammatory processes may contribute to psychiatric disorders and suicide. Earlier, we reported greater densities of perivascular phagocytes in dorsal prefrontal white matter (DPFWM) in suicide than in non-suicide deaths. To distinguish between greater vascularity and greater coverage of vessels by perivascular phagocytes, and to determine whether the excess of perivascular phagocytes is derived from microglia or from non-parenchymal immune cells, we made stereological estimates of vascular surface area density (AVTOTAL) by staining for glucose transporter Glut-1, and the fraction of vascular surface area (AF) immunoreactive (IR) for CD163 (CD163 AF) in dorsal and ventral prefrontal white and gray matter. Manner of death or psychiatric diagnosis showed no association with CD163 AF in any region. Suicide was associated with a lower AVTOTAL compared with non-suicides in DPFWM (p = 0.018) but not with AVTOTAL in the 3 other regions of interest. Thus, the earlier observation of increased density of perivascular phagocytes in DPFWM after suicide cannot be attributed to infiltration by peripheral monocytes or to increased vascularity. Greater AVTOTAL ventrally than dorsally (p = 0.002) was unique to suicide and white matter.
Topics: Adult; Blood Vessels; Female; Gray Matter; Humans; Male; Middle Aged; Phagocytes; Prefrontal Cortex; Suicide; White Matter
PubMed: 30496451
DOI: 10.1093/jnen/nly103