Medial Zone Research Articles

Perspective in Achieving Stratified Articular Cartilage Repair Using Zonal Chondrocytes.

Articular cartilage is composed of superficial, medial, and deep zones, which endow the tissue with biphasic mechanical properties to withstand shearing force and compressional loading. The tissue has very limited self-healing capacity once it is damaged due to its avascular nature. To prevent the early onset of osteoarthritis, surgical intervention is often needed to repair the injured cartilage. Current noncell-based and cell-based treatments focus on the regeneration of homogeneous cartilage to achieve bulk compressional properties without recapitulating the zonal matrix and mechanical properties, and often oversight in aiding cartilage integration between host and repair cartilage. It is hypothesized that achieving zonal architecture in articular cartilage tissue repair could improve the structural and mechanical integrity and thus the life span of the regenerated tissue. Engineering stratified cartilage constructs using zonal chondrocytes have been hypothesized to improve the functionality and life span of the regenerated tissues. However, stratified articular cartilage repair has yet to be realized to date due to the lack of an efficient zonal chondrocyte isolation method and an expansion platform that would allow both cell propagation and phenotype maintenance. Various attempts and challenges in achieving stratified articular cartilage repair in a clinical setting are evaluated. In this review, different perspectives on achieving stratified articular cartilage repair using zonal chondrocytes are described. The effectiveness of different zonal chondrocyte isolation and zonal chondrocyte phenotype maintenance methodologies during expansion are compared, with the focus on recent advancements in zonal chondrocyte isolation and expansion that could present a possible strategy to overcome the limitation of applying zonal chondrocytes to facilitate zonal architecture development in articular cartilage regeneration. Impact Statement The zonal properties of articular cartilage contribute to the biphasic mechanical properties of the tissues. Recapitulation of the zonal architecture in regenerated articular cartilage has been hypothesized to improve the mechanical integrity and life span of the regenerated tissue. This review provides a comprehensive discussion on the current state of research relevant to achieving stratified articular cartilage repair using zonal chondrocytes from different perspectives. This review further elaborates on a zonal chondrocyte production pipeline that can potentially overcome the current clinical challenges and future work needed to realize stratified zonal chondrocyte implantation in a clinical setting.

Hair cell morphological patterns and polarity organization in the sea lamprey vestibular cristae.

The inner ear of the sea lamprey was examined by scanning electron microscopy, antibody labeling with tubulin, Myo7a, Spectrin, and Phalloidin stain to elucidate the canal cristae organization and the morphology and polarity of the hair cells. We characterized the hair cell stereocilia bundles and their morphological polarity with respect to the kinocilia. We identified three types of hair cells. In Type 1 hair cells, the kinocilia were slightly longer than the tallest stereocilia. This type was located along the medial bank of the crista and their polarity, based on kinocilia location, was uniformly pointed ampullipetally. Type 2 hair cells that had kinocilia that were much longer than the stereocilia, were most abundant in the central region of the crista. This type of hair cell displayed variable polarity. Type 3 hair cells had extremely long kinocilia (~40-50 μm long) and with extremely short stereocilia. They were mostly located in the lateral zone crista and displayed ampullipetal polarity. Myo7a and tubulin antibodies revealed that hair cells and vestibular afferents are distributed across the canal cristae in the lamprey, covering the area of cruciate eminence; a feature that is absent in more derived vertebrates. Spectrin shows hair cells of varying polarities in the central zone. In this zone, some cells followed the main polarity vector (lateral) like those in medial and lateral zones, whereas other cells displayed polarities that carried up to 40° from the main polarity vector.

SECTOR DISCOURSE/TEXT IN THE NOMINATIVE FIELD OF THE COMPLEX CONCEPT WORD / LANGUAGE / SPEECH

The article is dedicated to the study of the complex concept WORD / LANGUAGE / SPEECH and its medial zone in the naпve picture of the world within a framework of a new scientific direction — dual linguistics: scientific and naive interpretation of language in the English lexicography. The complex concept WORD / LANGUAGE / SPEECH, which is verbalized by nominative units extracted from English general lexicographic sources, is considered. The nuclear zone of the naпve picture of the world counts three lexemes (which together contain 42 sememes), among which 161 semes have been filtered by means of seme analysis method. The most common semanteme, present in all nuclear lexemes, is the idea of the bilateral nature of any communicative unit. All of the nuclear zone lexemes in the primary dictionary position contain the seme, which emphasizes the unity of content and form of the phenomena under consideration. The medial zone of the nominative field of the verbalized WORD / LANGUAGE / SPEECH complex concept is many times bigger and more variable in comparison with the nuclear zone. It includes more than 700 lexical units with semantic components language, speech, communication. According to the thematic principle, the collected material was divided into 6 sectors: communication; units of language, speech; discourse, text; phonetical, grammatical and stylistic phenomena; language / dialect / slang, speaker; linguistics. The given sector contains nominative units of the English vocabulary to indicate various types of institutionalized discourse, primarily means of written fixation of human communication in public and private spheres. The evolution of verbal communication between people from ancient times to the present is reflected in a diverse palette of nominations of communicative phenomena of religious, artistic, scientific, legal and business, mass media and even everyday communication.

Establishing an Efficient Electroporation-Based Method to Manipulate Target Gene Expression in the Axolotl Brain

The tetrapod salamander species axolotl (Ambystoma mexicanum) is capable of regenerating injured brain. For better understanding the mechanisms of brain regeneration, it is very necessary to establish a rapid and efficient gain-of-function and loss-of-function approaches to study gene function in the axolotl brain. Here, we establish and optimize an electroporation-based method to overexpress or knockout/knockdown target gene in ependymal glial cells (EGCs) in the axolotl telencephalon. By orientating the electrodes, we were able to achieve specific expression of EGFP in EGCs located in dorsal, ventral, medial, or lateral ventricular zones. We then studied the role of Cdc42 in brain regeneration by introducing Cdc42 into EGCs through electroporation, followed by brain injury. Our findings showed that overexpression of Cdc42 in EGCs did not significantly affect EGC proliferation and production of newly born neurons, but it disrupted their apical polarity, as indicated by the loss of the ZO-1 tight junction marker. This disruption led to a ventricular accumulation of newly born neurons, which are failed to migrate into the neuronal layer where they could mature, thus resulted in a delayed brain regeneration phenotype. Furthermore, when electroporating CAS9-gRNA protein complexes against TnC (Tenascin-C) into EGCs of the brain, we achieved an efficient knockdown of TnC. In the electroporation-targeted area, TnC expression is dramatically reduced at both mRNA and protein levels. Overall, this study established a rapid and efficient electroporation-based gene manipulation approach allowing for investigation of gene function in the process of axolotl brain regeneration.

Osseous microarchitecture in frequent fracture zones of the distal clavicle.

Fracture classifications of the distal clavicle are based on ligamentous integrity. The influence of osseous microarchitecture on fracture occurrence, morphology, and the lesion's stability has not yet been investigated. We aimed to characterize osseous microarchitecture according to common fracture classification systems based on ligamentous integrity and investigated the possible effects of age, gender, and osteoporosis in distal clavicle fractures. N=20 human cadaveric distal clavicles were scanned using XtremeCT with an isometric voxel size of 82 μm. In the sagittal plane, each data set was evaluated in 11 sections of approximately 7 mm thickness. Three topographic regions were defined: the bone lateral to the trapezoid (LTR), intertubercular (ITR), and medial to the conoid (MCR) ligament. Cortical bone mineral density (BMD) [mgHA/cm3] and cortical porosity (1- (BV/TV) [%]) were determined and evaluated relative to age and gender. Along the mediolateral axis, there was an >20-fold increase in median cortical porosity (P≤.001). There were significant differences in cortical porosity between LTR and ITR (P≤.001) but not between ITR and MCR (P=.09). In ITR, cortical porosity was significantly greater in >60-year-old compared to younger donors (P=.01). For BMD, there was an >2-fold decrease toward the distal apex (P≤.001). BMD was significantly greater in ITR compared to LTR (P≤.001) and in MCR compared to ITR (P=.02). In ITR and MCR, clavicles of >60-year-old donors had significantly lower BMD values compared to younger donors (P<.01). Across all 3 regions, frequency distribution of low bone mass did not significantly differ between <60-year-olds and >60-year-olds (P>.6). The distal clavicle features a characteristic bony microarchitecture. The present study revealed a significant difference in bone quality of lateral, intertubercular, and medial zones of the distal clavicle and could specify target areas and strategies for surgical treatment of unstable fractures. Age, gender, and osteoporosis have a limited effect on bone quality and fracture genesis. In contrast, ligamentous quality is supposed to exert a substantial influence on fracture characteristics, especially in ITR. Fracture morphology of the distal clavicle is determined by a bony-ligamentous conjunction, which remains to be characterized.

Osteosynthese bei extraartikulärer proximaler Tibiafraktur

The treatment of extra-articular proximal tibial fractures is atherapeutic challenge due to the frequently significant soft tissue injury, the effect of the deforming forces and the need for an exact restoration of the bony alignment. Various methods of osteosynthesis are available for surgical stabilization. The locking plate osteosynthesis is the most frequently used procedure because of its good biomechanical stability, especially in osteoporotic bones, and the protection of the periosteal blood flow. Depending on the extent and stability of the defect zone, especially in the case of amedial comminuted zone and the bone quality, bilateral plate osteosynthesis can be necessary. If the proximal fragment is big enough, closed reduction and intramedullary nailing are possible. In the case of severely compromised soft tissue or very short epiphyseal fragments, the construction of an external fixator, e.g. hybrid external fixator, is recommended, which also allows definitive treatment under early full weight bearing. The most important complications are axial and torsional malalignments.

Orexinergic neurons in the hypothalami of an Asiatic lion, an African lion, and a Southeast African cheetah.

Employing orexin-A immunohistochemistry, we describe the distribution, morphology, and nuclear parcellation of orexinergic neurons within the hypothalami of an Asiatic lion (Panthera leo subsp. persica), an African lion (Panthera leo subsp. melanochaita), and a Southeast African cheetah (Acinonyx jubatus subsp. jubatus). In all three felids, the clustering of large, bipolar, and multipolar hypothalamic orexinergic neurons primarily follows the pattern observed in other mammals. The orexinergic neurons were found, primarily, to form three distinct clusters-the main, zona incerta, and optic tract clusters. In addition, large orexinergic neurons were observed in the ventromedial supraoptic region of the hypothalamus, where they are not typically observed in other species. As has been observed in cetartiodactyls and the African elephant, a cluster of small, multipolar orexinergic neurons, the parvocellular cluster, was observed in the medial zone of the hypothalamus in all three felids, although this parvocellular cluster has not been reported in other carnivores. In both subspecies of lions, but not the cheetah, potential orexin-immunopositive neurons were observed in the paraventricular hypothalamic nucleus, supraoptic nucleus, the lateral part of the retrochiasmatic area, and the inner layer of the median eminence. The distribution and parcellation of orexinergic neurons in the hypothalami of the three felids studied appear to be more complex than observed in many other mammals and for the two subspecies of lion may be even more complex. These findings are discussed in terms of potential technical concerns, phylogenetic variations of this system, and potentially associated functional aspects of the orexinergic system.

Fault systems in the offshore sector of the Campi Flegrei caldera (southern Italy): Implications for nested caldera structure, resurgent dome, and volcano-tectonic evolution

The structure of a caldera may influence its activity, making its understanding crucial for hazard assessment. Here, we analysed high-resolution seismic profiles in the Campi Flegrei (southern Italy) offshore sector. We recognised two main fault systems, including those associated with the formation of the caldera and those affecting the resurgent dome. The former system comprises three broadly concentric fault zones (inner, medial and outer ring fault zones) depicting a nested caldera geometry. Considering the relations between faults and seismic units that represent the marine and volcaniclastic successions filling the caldera, all ring faults were formed during the Campanian Ignimbrite eruption (40 ka) and subsequently reactivated during the Neapolitan Yellow Tuff eruption (15 ka). In this last caldera-forming event, the inner and medial fault zones accommodated most of the collapse and were episodically reactivated during the younger volcano-tectonic activity. The second fault system occurs in the apical zone of the resurgent dome and comprises dominantly high-angle normal faults that are mainly related to the volcano-tectonic collapse that followed the Agnano-Monte Spina Plinian eruption (4.55 ka). Finally, we provide a volcano-tectonic evolutionary model of the last 40 kyr, considering the interplay among ring and dome faults activity, volcaniclastic sedimentation, ground deformation and sea-level changes.

Afferent and efferent connections of the nucleus posterior tuberis in the firemouth cichlid, Thorichthys meeki

The nucleus posterior tuberis (NPT) in teleost fishes, also called posterior tuberal nucleus, is situated in the posterior tuberculum of the diencephalon. It is fused across the midline and densely packed with small cells, but little is known about its connections. In this study, the afferent and efferent connections of the NPT were examined by means of tracer applications of the carbocyanine dye DiI in the firemouth cichlid, Thorichthys meeki. Retrogradely labeled cell bodies were found in the corpus mamillare and nucleus periventricularis of the inferior lobe; and anterogradely labeled terminal fibers were detected in the medial zone of the dorsal telencephalon, medial part of the nucleus lateralis tuberis, dorsal posterior thalamic nucleus, torus lateralis, medial part of the nucleus diffusus of the inferior lobe, and tectum opticum. All these connections show an ipsilateral tendency. The NPT is apparently a significant relay nucleus in the diencephalon of T. meeki, and possibly involved in a variety of feedback circuits. It seems also to be part of a tecto-hypothalamo-telencephalic pathway in cichlids.

Nothobranchius balamaensis (Cyprinodontiformes: Nothobranchiidae), a new species of annual killifish from northern Mozambique.

A new seasonal killifish of the genus Nothobranchius is described from the Montepuez River system in northern Mozambique. The new species, Nothobranchius balamaensis Bragana Chakona, is differentiated from congeners by its characteristic colour pattern and molecular data further support its taxonomic distinctiveness. Phylogenetic results based on two mitochondrial and three nuclear genes confirms N. balamaensis is closely related to N. kirki and N. wattersi; all three belonging to the Coastal-Inland Clade. The new species is most similar in colour pattern to N. kirki sharing the characteristic of a deep red-orange colouration in the basal, proximal, and medial zones of the caudal and anal fins that grades to orange in the distal zone. This is a key feature that distinguishes these two species from all other Nothobranchius. The main distinguishing features between the new species and N. kirki is the presence of a light blue to white band or series of irregular markings in the proximal zone of the anal fin in N. kirki, versus the absence of such a colour pattern element in N. balamaensis, as well as differences in the dorsal fin pattern. When compared to all population groups of N. wattersi, the colour pattern of N. balamaensis is distinctive. Nothobranchius balamaensis is a relatively slender member of the genus, a characteristic that clearly distinguishes it from both N. kirki and N. wattersi. Nothobranchius balamaensis is currently only known from a few specimens from the type locality.

Posterior intercostal flap: an anatomical study and best flap design

BackgroundPosterior intercostal arteries perforators (PICAPs) and lateral intercostal arteries perforators (LICAPs) are great vascular pedicles. Between the 4th and 11th spaces, they arise from the thoracic aorta. These are large perforators that can be the basis of many flaps. Yet, these perforators are underrated as they are poorly studied and scarcely utilized in plastic reconstructions.MethodsTwenty (ten males and ten females) adult cadaveric dissections were done on both sides to study the types, locations, and sizes of posterior intercostal perforators to help design flaps based on them in the best possible way. Perforators were assigned into one of 3 topographical zones of the back (medial, intermediate, and lateral).ResultsThe skin of the back was divided into 3 vertical zones: medial, intermediate, and lateral. Posterior intercostal arteries perforators (PICAPs) were found in the medial and intermediate zones. Medial zone PICAPs were large and appeared at the medial border of erector spinae (Es). Intermediate zone PICAPs appeared at the lateral border of Es and passed through latissimus dorsi (Ld) before reaching the skin. Lateral zone perforators were branches of lateral intercostal arteries and were divided into 2 types: (1) posterior branches of lateral intercostal perforators: simply named posterior lateral perforators (PLs); they were small and present in most of the spaces, and (2) anterior branches of lateral intercostal perforators (LICAPs): they were large, dominant pedicles and were found mainly in the 4th to the 7th spaces.ConclusionPICAPs and LICAPs are constant and of enormous size and run for a great distance in the skin. They can be utilized as any type of flap.

SECTOR LANGUAGE IN THE NOMINATIVE FIELD OF THE COMPLEX CONCEPT WORD / LANGUAGE / SPEECH

The article is dedicated to the study of the complex concept WORD / LANGUAGE / SPEECH and its medial zone in the naïve picture of the world within a framework of a new scientific direction – dual linguistics: scientific and naive interpretation of language in the English lexicography. The study of the verbalized concept involves, first of all, the formation of its nominative field, i.e. the collection and structuring into a single whole of all nominative units that denote core concepts, together with their vocabulary definitions. The factual material obtained in this way allows a careful analysis of the etymology and semantics of all collected lexical items. The complex concept WORD / LANGUAGE / SPEECH, which is verbalized by nominative units extracted from English general lexicographic sources, is considered. The nuclear zone of the naïve picture of the world counts three lexemes (which together contain 42 sememes), among which 161 semes have been filtered by means of seme analysis method. The most common semanteme, present in all nuclear lexemes, is the idea of the bilateral nature of any communicative unit. All of the nuclear zone lexemes in the primary dictionary position contain the seme, which emphasizes the unity of content and form of the phenomena under consideration. The medial zone of the nominative field of the verbalized WORD / LANGUAGE / SPEECH complex concept is many times bigger and more variable in comparison with the nuclear zone. It includes more than 700 lexical units with semantic components language, speech, communication. According to the thematic principle, the collected material was divided into 6 sectors: communication; units of language, speech; discourse, text; phonetical, grammatical and stylistic phenomena; language / dialect / slang, speaker; linguistics. The thematic sector language / dialect / slang, the speaker comprises 40 vocabulary units, which nominate: a) the concept of language as a means of communication and its territorial, social and professional subtypes, and b) the concept of a person who speaks / does not speak a language or uses the language.

Гістологічна характеристика печінки плітки (Rutilus rutilus Linnaeus, 1758) як біоіндикатора якості водного середовища

Purpose. To assess the variability of the histological parameters of the medial zone of roach (Rutilus rutilus) liver. To establish the level of effect of the transformed conditions of existence on fish physiological status. To determine the prospect of using histological monitoring data in ichthyological practice to assess the morphofunctional state of fish. Methodology. Primary materials were obtained in different parts of the Southern Bug River, which differ in their degrees of pollution. Lab processing of ichthyological samples was performed in accordance with generally recognized methods and manuals. Histological studies were carried out using proprietary equipment and original techniques specifically designed for diagnosing fish tissues. The obtained results were processed by the methods of variation statistics using MS Excel with an emphasis on the errors of the average values. Findings. Microanatomical studies of roach hepatic parenchyma allowed establishing that the most significant changes occured in the transformed conditions of existence and were contrastingly recorded in the medial zone of the organ, which could conditionally be considered a bioindicative zone. With the potential effect of toxicants dissolved in water, a shift in cell function was observed in the liver. Visually, this was manifested as a change in the structuring of cytoplasmic inclusions and in the intensity of nucleus staining, which simultaneously occured with a direct shift in cytological characteristics. An 1.20-fold increase in cell area adequately leads to an 1.18-fold increase in the cytoplasm area, as well as the Hertwig constant or nuclear-cytoplasmic ratio (0,25-0,28), which was statistically significant. The obtained data indicate a change in the nature of intracellular metabolism. An increase in the number of intracellular cavities is a direct evidence of the attenuation of the glycogen-accumulative function of hepatocytes. An increase in the nucleolus/nucleus diameter ratio (0.28) indicates a change in cellular function, which occurs through the activation of lipid synthesis. No typical necrosis foci were found in the parenchyma of the liver of fish from the places of concentration of commercial effluents, which are an evidence of a moderate accumulation of fat-soluble pollutants in the liver. The absence of pronounced pathologies in most individuals indicates significant reserve-compensatory potencies of the organ. The presence of individual hepatocytes with two nucleoli in the nuclei in the liver parenchyma allows judging the borderline, i.e. the prepathological state of the organ. In some cases, an increase in the proportion of dystrophic hepatocytes with large vacuoles filled with an optically transparent liquid was established, which allowed identifying an irreversible pathology - liver balloon dystrophy, resulting from a severe impairment of cellular metabolism. Histological analysis of roach liver parenchyma from conditionally clean and polluted waters allowed, in parallel, establishing relatively low levels of intraspecific and individual variability of cell populations. The revealed fact testifies to the plasticity of the liver as an organ with significant reserve potencies, which are contrastingly manifested under conditions of technogenic pressure in waters of various origins and intended purposes. This perspective provides evidence for the evolutionary definition of the liver as the body’s universal detoxification system. Originality. New data are presented, as well as existing data on the normal and altered histological structure of the medial zone of the liver of roach, which live under transformed conditions of existence, were significantly updated. For the first time, a comparative histological and cytological analysis of the structure of the medial zone of the liver of age-1+ roach was carried out. Based on a comparative analysis, the information on the taxonomic features of compensatory changes in liver tissue components in polluted water areas was renewed and updated. Practical walue. The information obtained is of value in morphophysiological studies, as well as in ichthyological practice in connection with the modern problem of lowering the vital status of fish populations, which exists in conditions of degraded aquatic ecosystems. The use of the obtained data allows qualitative assessment of the physiological status of fish in order to predict environmental hazards in water areas of different origin and purpose. Key words: roach, parenchyma, liver, hepatocyte, bioindication, cellular function, water area.

Sampling a gradient of red snow algae bloom density reveals novel connections between microbial communities and environmental features

Snow algae blooms and associated microbial communities play large roles in snow ecosystem processes. Patterns and mechanisms underpinning snow algae bloom spatial distribution and associated microbial community assembly dynamics are poorly understood. Here we examine associations of microbial communities and environmental measures between/within snow algae blooms. Snows from the Cascade Mountains and the Rocky Mountains (USA) were collected from medial (M), peripheral (P), and adjacent (A) zones of red snow algae blooms. Medial snow shows increased levels of pollen, lower oxidation–reduction potential, decreased algal and increased bacterial richness, and increased levels of potassium when compared to A and P within the same bloom. Between the Cascade and Rocky Mountains, fungal communities are distinct but bacterial and algal communities show little differentiation. A weighted OTU co-expression analysis (WOCNA) explores OTU modules and their differential correlation with environmental features, suggesting certain subcommunities may be altered by ecological patterns. Individual OTU interaction networks (fungi and bacteria) show high levels of connectivity compared to networks based on the red snow alga Sanguina nivaloides, which underscores associative differences between algal dominated networks and other taxa.

Negative Effects on Neurogenesis, Ovariogenesis, and Fitness in Sea Turtle Hatchlings Associated to ex situ Incubation Management

Sea turtle egg relocation and hatchery incubation (hereafter termed ex situ incubation) is an effective strategy to protect clutches when in situ egg incubation is not viable. Nevertheless, it negatively affects the ontogenesis of male gonads and brain areas homologous to the mammalian hippocampus, as well as body size and fitness. Thus, it is imperative to analyze the effects of ex situ incubation on other developmental aspects and extend these observations to females. This work evaluated the effect of ex situ management on neurogenesis (cell proliferation in the dorsal and medial ventricular zones, neuronal integration in the dorsomedial and medial cortices), ovary cell proliferation, body size (mass and length) and self-righting ability. Additionally, this study examined if the incubation microenvironment is different between in situ and ex situ nests and whether it could contribute to explain the biological traits. An analysis of principal components showed differences in biological variables of hatchlings between in situ and ex situ clutches, driven by contrasting temperatures and silt composition. Each biological variable was also analyzed with linear mixed models using in situ vs. ex situ clutches, abiotic variables and their interaction. Turtles from ex situ clutches showed: (1) fewer proliferating cells in the dorsal and medial ventricular zones; (2) less mature neurons in the dorsomedial and medial cortices; (3) ovaries with a lesser number of proliferating cells; (4) lower body mass and length at emergence; and (5) slower self-righting time. Together, the results suggest that ex situ incubation in hatcheries is related to a slowing down of neurogenesis, ovariogenesis, body size and self-righting ability in hatchlings. Future studies should evaluate the effect of ex situ incubation on cognitive and reproductive performance to understand the long-term consequences of altered organogenesis. These studies should also disentangle the differential contribution of egg movement, reburial, nesting environment and parental origin to development. This information would likely result in better conservation strategies for sea turtles.

Internal hernia caused by bridge formation between the medial and lateral segments of the liver: a case report

BackgroundDespite numerous reports on ischemic bowel obstruction caused by internal hernia, no case presentation has been reported of an internal hernia caused by a bridge formed between the medial and lateral zones of the liver. Herein, we report the first case of ischemic bowel obstruction caused by a hepatic bridge.Case presentationA 24-year-old man complaining of abdominal pain was referred to our hospital and admitted. Computed tomography showed formation of a closed loop of small bowel with a hernia orifice near the hilar region, and poor contrast of the prolapsed small bowel. We suspected ischemic bowel obstruction caused by an internal hernia with a fissure of the greater omentum as the hernia orifice, and performed emergency surgery. Laparoscopic observation revealed that the medial and lateral segments of the liver formed a bridge on the dorsal side at the liver portal, and that the small intestine was ischemic in the gap created between the bridge and the medial and lateral liver segments. A Meckel’s diverticulum was also invaginated in the gap. The bridge was dissected out and the hernia orifice was opened to release the bowel obstruction. The small bowel was preserved and the Meckel’s diverticulum was resected. The patient’s postoperative course was uneventful.ConclusionsWe experienced a case of ischemic bowel obstruction caused by hepatic bridge formation, which was successfully treated by laparoscopic surgery.

Integrated Behavioral, Genetic and Brain Circuit Visualization Methods to Unravel Functional Anatomy of Zebrafish Amygdala.

The mammalian amygdala is a complex forebrain structure consisting of a heterogeneous group of nuclei derived from the pallial and subpallial telencephalon. It plays a critical role in a broad range of behaviors such as emotion, cognition, and social behavior; within the amygdala each nucleus has a distinct role in these behavioral processes. Topological, hodological, molecular, and functional studies suggest the presence of an amygdala-like structure in the zebrafish brain. It has been suggested that the pallial amygdala homolog corresponds to the medial zone of the dorsal telencephalon (Dm) and the subpallial amygdala homolog corresponds to the nuclei in the ventral telencephalon located close to and topographically basal to Dm. However, these brain regions are broad and understanding the functional anatomy of the zebrafish amygdala requires investigating the role of specific populations of neurons in brain function and behavior. In zebrafish, the highly efficient Tol2 transposon-mediated transgenesis method together with the targeted gene expression by the Gal4-UAS system has been a powerful tool in labeling, visualizing, and manipulating the function of specific cell types in the brain. The transgenic resource combined with neuronal activity imaging, optogenetics, pharmacology, and quantitative behavioral analyses enables functional analyses of neuronal circuits. Here, we review earlier studies focused on teleost amygdala anatomy and function and discuss how the transgenic resource and tools can help unravel the functional anatomy of the zebrafish amygdala.

Determination of a neurologic safe zone for bicortical S1 pedicle screw placement

BACKGROUND CONTEXTLumbosacral fixation is commonly used for the management of lumbosacral instability. As the sacrum mainly consists of cancellous bone, bicortical fixation, in which the pedicle screw penetrates the anterior sacral cortex, can help increase the strength of fixation. However, this method carries a risk to the L5 nerves which lie anterior to the sacrum at this level. PURPOSEThe goal of this study is to determine a safe zone for the placement of S1 pedicle screws to decrease the likelihood of L5 nerve injury. STUDY DESIGNRetrospective imaging review. PATIENT SAMPLEThis study evaluated imaging data of patients who underwent lumbar spine magnetic resonance imaging (MRI) at our institute between September 1, 2020 and September 1, 2021. OUTCOME MEASUREST1-weighted axial MRIs were measured at the level of S1 pedicle screw placement. The space medial and lateral to the L5 nerve root on the anterior sacrum were measured and defined as safe zones. Additionally, the nerve width and sacral lengths were measured at this level. METHODSThe distribution of the measurements were evaluated to determine a medial and lateral safe zone, as well as the average nerve width at the level of S1 pedicle screw placement. Correlation analysis was performed to determine a relationship between safe zone sizes and sacral size. RESULTSA total of 400 MRIs were analyzed. The average medial safe zone measured was 32.8 mm (95% CI: 32.2–33.4) with no nerves lying within 22.3 mm of the midline sacrum. The average lateral safe zone measured was 17.7 mm (95% CI: 17.1–18.2), with no nerves within 5.3 mm of the lateral border of the sacrum. The average nerve root width was 6.2 mm (95% CI: 6.13–6.34). An increased sacral length was associated with a larger medial (p<.001) and lateral (p<.001) safe zone. CONCLUSIONSOur study revealed lateral and medial safe zones for the placement of S1 pedicle screws to avoid iatrogenic nerve injury in a retrospective cohort of 400 patients. There were no L5 nerve roots found within 22.3 mm of the sacrum's mid-axis or within 5.3 mm of the sacrum's anterolateral border. These defined safe zones can be used during pedicle screw planning and placement to decrease the risk of injury to the L5 nerve root.

SECTOR LINGUISTICS IN THE NOMINATIVE FIELD OF THE COMPLEX CONCEPT WORD / LANGUAGE / SPEECH

The article is dedicated to the study of the complex concept WORD / LANGUAGE / SPEECH and its medial zone in the naïve picture of the world within a framework of a new scientific direction – dual linguistics: scientific and naive interpretation of language in the English lexicography. The complex concept WORD / LANGUAGE / SPEECH, which is verbalized by nominative units extracted from English general lexicographic sources, is considered. The nuclear zone of the naïve picture of the world counts three lexemes (which together contain 42 sememes), among which 161 semes have been filtered by means of seme analysis method. The most common semanteme, present in all nuclear lexemes, is the idea of the bilateral nature of any communicative unit. All of the nuclear zone lexemes in the primary dictionary position contain the seme, which emphasizes the unity of content and form of the phenomena under consideration. The medial zone of the nominative field of the verbalized WORD / LANGUAGE / SPEECH complex concept is many times bigger and more variable in comparison with the nuclear zone. It includes more than 700 lexical units with semantic components language, speech, communication. According to the thematic principle, the collected material was divided into 6 sectors: communication; units of language, speech; discourse, text; phonetical, grammatical and stylistic phenomena; language / dialect / slang, speaker; linguistics. The analysis of the relevant part of the sample made it possible to understand how the average native English speaker, without being an expert in the field of linguistics, represents a holistic system of language learning and individual components of this system. Dictionaries clearly differentiate between two branches of human language: linguistics, which is the scientific study of language structure, grammar, syntax, and phonetics, and philology, which is the field of scientific knowledge about the structure, historical development, and connections of language to other languages.

Commentary: A technical revisit to the glabellar flap.

We have read an interesting article by Balchev et al. published in the current issue of IJO. They included 15 patients who were followed up over 36 months. The authors have described the use of glabellar flap (GF) to reconstruct medial canthal region defects. They have categorized the medial canthal region into the upper, medial, and lower zone in reference to the medial canthal tendon. They used V-Y glabellar rotation, advancement, or combined transposition flap techniques. By definition, the glabella is a region between the eyebrows that has potential skin to reconstruct surrounding areas like the medial canthus and nose.[1] The glabellar myocutaneous flap is a simple, safe, and effective procedure that provides anterior lamellae and vascular supply to the reconstructed region.[12] The advantages being similar skin color, texture, and thickness with minimal postoperative flap shrinkage or contracture.[123] Moreover, the vascular supply leads to faster healing with minimal collateral damage. Maloof and Leatherbarrow[4] (2000) provided a detailed description of the GF. They conceptualized the idea of anatomical and surgical medial canthus, the latter being much larger in area. The surgical medial canthus extended from the subbrow region (superior) to the upper cheek (inferior) and medially up to the midline over the nose. They believed that any reconstruction of surgical medial canthus could be performed using a glabellar V-Y flap. The critical factors in preoperative planning of GF include[4]: Size, depth, and location of the defect Orientation and alignment of the V-Y flap Depth of the medial canthus or nasal bridge prominence Age and skin texture of the patient. The smaller, shallower, and medial defects have favorable outcomes. The prominent nasal bridge or deep medial canthus will need a longer flap to reach up to the lateral edge of the defect. Younger patients have tighter skin that may have intraoperative implications. Skin marking is a vital part of the GF harvesting process. After the surgical excision of the lesion and determining its tumor-free margins, a surgical marker pen is used to draw the triangular or rectangular GF. The flap size depends on the size of the defect, distance from the glabella, and the depth of the medial canthus.[1234] The first arm of the V-shaped GF, arises tangentially from the superolateral edge of the defect, passes superomedial toward the midline apex. The second arm (preferably curved in shape) is fashioned at an acute angle, and its length is kept slightly longer to accommodate the bend of flap tissue [Fig. 1]. The flap should have a broad base for better vascular supply. The dissection should be limited to the skin and subcutaneous tissue, avoiding the involvement of corrugators and procerus muscles. The suture fixation of the flap base to the underlying periosteum prevents traction and preserves canthal concavity. The donor site should be closed in two layers—the deeper muscular layer (4-0 or 5-0 absorbable sutures) and the skin with 4-0 or 5-0 prolene or nylon (preferably horizontal mattress sutures). For larger defects, the extended, modified advancement flap, rotational flap, or bilobed GF can be used.[145]Figure 1: A glabellar flap fashioned for the reconstruction of left medial canthus lesion showing the first and second arms with a broad baseThe complex scenarios that may compromise the outcomes of GF include[4]: Young patients with tight forehead and facial skin Very deep medial canthus Dense hairs in-between eyebrows (synophrys) Large and irregular defect extending more laterally or inferiorly. The limitations of GF include consecutive midline forehead scar, medialization of the eyebrows, lymphedema, and flap uptake-related complications (necrosis, infection, etc.).[45] Nevertheless, the GF and its modifications constitute a simple, reproducible, and efficient technique providing excellent skin color match with satisfactory aesthetic and functional outcomes.[3]