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Intelligible communication with others as well as covert conscious thought requires us to combine a representation of the external world with inner abstract concepts.Interaction with the external world through sensory perception and motor execution is arranged as sequences in time and space, whereas abstract thought and invariant categories are independent of the moment. Using advanced MRI-based fibre tracking on high resolution data from 183 participants in the Human Connectome Project, we identified two large supramodal systems comprising specific cortical regions and their connecting fibre tracts; a dorsal one for processing of sequences in time and space, and a ventral one for concepts and categories. We found that two hub regions exist in the executive front and the perceptive back of the brain where these two cognitive processes converge, constituting a dual-loop model. The hubs are located in the onto- and phylogenetically youngest regions of the cortex. We propose that this hub feature serves as the neural substrate for the more abstract sense of syntax in humans, i.e. for the system populating sequences with content in all cognitive domains. The hubs bring together two separate systems (dorsal and ventral) at the front and the back of the brain and create a closed-loop. The closed-loop facilitates recursivity and forethought, which we use twice; namely, for communication with others about things that are not there and for covert thought.

Background: Calcified lumbar disc herniations (CLDH) causing calcified ventral stenosis pose a therapeutic challenge to the treating surgeon due to their neural adhesions, location, and hardness., Methods: This retrospective study analyzed all the cases of CLDH/calcified ventral stenosis managed by transforaminal endoscopic lumbar discectomy with a minimum follow-up of 24 months. The preoperative images were analyzed for the level, migration; and grade (Lee's migration zones), and location (Michigan State University classification). Detailed surgical technique and intraoperative parameters including the duration of surgery and complications have been recorded. The clinical parameters including visual analog scale (VAS), Oswestry disability index (ODI), length of stay in hospital, days of return to basic work, and patient satisfaction index were analyzed. Postoperatively the images were analyzed for the adequacy of decompression., Results: The mean VAS for back pain and leg pain was 4.7 ± 2.6 (0-9), and 7.45 ± 2.2 (1-10), respectively. The mean preoperative ODI was 78.2 ± 13.2 (63.2-95.6). Nineteen patients (24%) had neurological deficits preoperatively. The mean duration of surgery was 90.5 ± 15.8 (58-131) minutes. Postoperative magnetic resonance imaging revealed adequate decompression in 97.5% (n = 77). The mean duration of hospital stay was 1.05 ± 0.22 (1-2) days, and the postoperative back and leg pain VAS was 1.14 ± 1.2 (0-3) (P < 0.05) and 1.7 ± 0.5 (0-6) (P < 0.05), respectively. The ODI at final follow-up was 6.5 ± 3.7 (2.2-18) (P < 0.05). Neurological recovery occurred in 17 (89.5%) patients and they returned to basic work/jobs in 19.5 ± 3.3 (14-26) days. The mean patient satisfaction index was 1.18 ± 0.47 (1-2) at a mean follow-up of 5.52 ± 2.91 (2-12.75) years., Conclusions: Transforaminal endoscopic lumbar discectomy is a complete, safe, and efficacious procedure in patients with CLDH with earlier recovery considering the surgery is performed with the patient being awake., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: There are controversies about the benefits of prophylactic antibiotics in the prevention of postoperative surgical site infection (SSI) in mesh herniorrhaphy for a long time. This study aimed to evaluate the effectiveness and efficacy of systemic prophylactic cefazolin in prevention of wound infection in various types of hernia repair with mesh materials. Methods: This is a prospective randomized control study. We evaluated wound infection rates in 395 patients with various kinds of hernia who underwent elective mesh repair using polypropylene mesh from 2007 to 2011. A total of 237 (60.0%) patients received prophylactic cefazolin (study group) and the remaining 158 (40.0%) patients did not receive any prophylactic antibiotics (control group). Patients were followed for infection at the following periods after the operation by an independent surgeon: 10 days, 30 days, 12 months, and then annually for at least 2 years. Results: Eight (2.03%) patients had infection in the site of surgery [2 (1.27%) in the control group and 6 (2.53%) in the study group]. The distribution of infection was not significantly different between the two groups (p = 0.364). The superficial infections were managed by drainage and irrigation. One patient from the study group developed deep SSI and was readmitted and subsequently received antibiotic therapy, drainage, and debridement. Conclusion: Preoperative administration of single-dose cefazolin for prosthetic hernia repairs did not markedly decrease the risk of wound infection. Our results do not support the use of cefazolin as a prophylactic antibiotic for various kinds of abdominal wall hernia repair with mesh.

Ventral hernia repair is one of the most frequently performed general surgery operations in the world, yet the treatment of clean-contaminated and contaminated cases remains controversial. Biologic mesh has been thought to resist infection, decrease chronic wound complications, and reduce the need for reoperation. Their use continues to be predominant in contaminated and dirty cases. This article is a comprehensive review of what mesh to choose in both clean and contaminated single-staged, open ventral hernia repair with further considerations of tissue incorporation characteristics, cost, safety profiles, complications, recurrence, and long-term outcomes., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Objectives: In the practice of intrathecal drug delivery, consensus exists regarding the cephalad to caudad location of the catheter tip relative to dermatomal distribution of pain. However, data are lacking on the importance of dorsal vs ventral tip location relative to the spinal cord. We hypothesize that a dorsally placed catheter tip improves efficacy because of closer proximity to nociceptive pathways., Materials and Methods: A retrospective review of 298 patients with cancer with intrathecal drug delivery systems implanted at the Huntsman Cancer Institute from May 2014 to June 2020 was performed. Patients were stratified by catheter tip location zones based on available radiographic studies. Patient-controlled intrathecal medication dose requirements and rate of change were compared with catheter zone and other variables, including the presence of adjuncts such as bupivacaine and ziconotide., Results: A total of 158 patients were suitable for analysis demonstrating a dorsal tip in 63.9% (n = 101) and ventral tip in 36.1% (n = 57), with a median follow-up of 17 days (interquartile range [IQR], 10-24). There was no difference in daily dose change from implant to discharge between the dorsal group 8.2% (IQR, 0.0-41.5) and ventral group 20.8% (IQR, 0.0-66.7; p = 0.12). Daily dose change from discharge to follow-up was 2.6% (IQR, 0.0-7.1) in the dorsal group and 1.8% (IQR, 0.0-5.7) in the ventral group (p = 0.92). Catheter tip location had no impact on systemic opioid use., Conclusions: We did not find significant associations between dorsal vs ventral catheter tip location and measures of pain relief, including change in intrathecal dose or systemic opioid use., (Copyright © 2022 International Neuromodulation Society. Published by Elsevier Inc. All rights reserved.)

Fragile X syndrome (FXS) is a neurodevelopmental disorder caused by the selective loss of the expression of the Fmr1 gene. Key symptoms in FXS include intellectual impairment and abnormal anxiety-related behaviors. Fmr1 knockout (KO) mice exhibited reduced anxiety on two behavioral tests as well as a blunted corticosterone response to acute stress. Spatial learning and memory was not impaired when tested with both the classic Morris water and Plus-shaped mazes. Adult hippocampal neurogenesis has been associated with spatial learning and memory and emotions such as anxiety and depression. The process of neurogenesis appears abnormal in young adult Fmr1 KO mice, with significantly fewer bromodeoxyuridine-positive cells surviving for at least 4 weeks in the ventral subregion of the dentate gyrus (DG), a hippocampal subregion more closely associated with emotion than the dorsal DG. Within this smaller pool of surviving cells, we observed a concomitant increase in the proportion of surviving cells that acquire a neuronal phenotype. We did not observe a clear difference in cell proliferation using both endogenous and exogenous markers. This work indicates that loss of Fmr1 expression can alter anxiety-related behaviors in mice as well as produce region-specific alterations in hippocampal adult neurogenesis.

Objective: Cervical meningiomas are uncommon intradural-extramedullary tumors that have a tendency to be situated anterior to the spinal cord. The optimal surgical corridor to reach purely ventral cervical meningiomas has not been established. This article presents a series of patients with ventral cervical meningiomas treated via 1 of 2 microneurosurgical approaches: the anterior approach with corpectomy and fusion or the posterolateral approach., Methods: Eight patients who underwent surgical resection of solitary, histopathologically confirmed, intradural-extramedullary cervical meningiomas of purely ventral location were retrospectively examined. Preoperative and postoperative Nurick scores quantified the degree of ambulatory function. Patients were followed for an average of 2.1 years after surgery. Postoperative imaging was performed to determine the extent of resection and to assess for tumor recurrence., Results: Two patients with lower cervical meningiomas underwent resection via an anterior approach with single-level corpectomy and fusion. Six patients were treated via a posterolateral approach including ipsilateral hemilaminectomy and partial facetectomy without fusion. No intraoperative or postoperative complications were observed. Gross total resection was achieved in 8 of 8 patients, although 1 patient exhibited tumor recurrence. Improvement in ambulatory function was observed in all patients., Conclusions: Purely ventral cervical meningiomas are uncommon and pose unique technical challenges for neurosurgeons. We document favorable outcomes from 2 cases of lower cervical meningioma treated via an anterior approach and 6 cases of upper cervical tumors treated via a posterolateral approach. This series demonstrates operative considerations for effectively managing ventral cervical meningiomas., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objective: To study whether and when mere dorsal decompression is enough in the full endoscopic key hole technique for foraminal stenosis., Methods: We retrospectively reviewed a total of 22 patients with cervical foraminal stenosis who underwent full endoscopic key hole mere dorsal decompression in our institute from October 2016 to October 2017., Results: Preoperative neck disability index, neck visual analog scale score, and arm visual analog scale score were 25.8 ± 0.8, 4.9 ± 0.6, and 7.5 ± 0.5 in the group. Immediate postoperative scores were 6.9 ± 0.9, 1.3 ± 0.9, and 1.4 ± 0.5. Follow-up scores at 3 months (7.0 ± 0.9, 1.9 ± 0.6, and 2.7 ± 0.9), 6 months (7.3 ± 0.9, 2.1 ± 0.9, and 1.9 ± 0.5), and 12 months (7.6 ± 0.5, 2.5 ± 0.8, and 2.1 ± 0.7). The symptoms had improved significantly (P < 0.05). According to the Macnab criteria, 15 patients reported excellent results, 2 reported good results, and 2 reported fair results at the 12-month follow-up., Conclusions: Stenosis is mainly caused by dorsal structures; mere dorsal decompression is enough. In both cases, the ventral and dorsal structures contributed to the stenosis. When there is no herniated soft fragment contributing to the stenosis, ventral decompression is not always necessary. If intraoperative exploration detects less tension formed by the ventral abnormal structures, mere dorsal decompression is enough to settle the symptoms., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Distinct classes of neurons arise at different positions along the dorsal-ventral axis of the spinal cord leading to spinal neurons being segregated along this axis according to their physiological properties and functions. Thus, the neurons associated with motor control are generally located in, or adjacent to, the ventral horn whereas the interneurons (INs) that mediate sensory activities are present within the dorsal horn. Here, we review classic and recent studies examining the developmental mechanisms that establish the dorsal-ventral axis in the embryonic spinal cord. Intriguingly, while the cellular organization of the dorsal and ventral halves of the spinal cord looks superficially similar during early development, the underlying molecular mechanisms that establish dorsal vs ventral patterning are markedly distinct. For example, the ventral spinal cord is patterned by the actions of a single growth factor, sonic hedgehog (Shh) acting as a morphogen, i.e., concentration-dependent signal. Recent studies have shed light on the mechanisms by which the spatial and temporal gradient of Shh is transduced by cells to elicit the generation of different classes of ventral INs, and motor neurons (MNs). In contrast, the dorsal spinal cord is patterned by the action of multiple factors, most notably by members of the bone morphogenetic protein (BMP) and Wnt families. While less is known about dorsal patterning, recent studies have suggested that the BMPs do not act as morphogens to specify dorsal IN identities as previously proposed, rather each BMP has signal-specific activities. Finally, we consider the promise that elucidation of these mechanisms holds for neural repair., (© 2019 Elsevier Inc. All rights reserved.)

Background: Acutely stressful experiences can trigger neuropsychiatric disorders and impair cognitive processes by altering hippocampal function. Although the intrinsic organization of the hippocampus is highly conserved throughout its long dorsal-ventral axis, the dorsal (anterior) hippocampus mediates spatial navigation and memory formation, whereas the ventral (posterior) hippocampus is involved in emotion regulation. To understand the molecular consequences of stress, detailed genome-wide screens are necessary and need to distinguish between dorsal and ventral hippocampal regions. While transcriptomic screens have become a mainstay in basic and clinical research, proteomic methods are rapidly evolving and hold even greater promise to reveal biologically and clinically relevant biomarkers., Methods: Here, we provide the first combined transcriptomic (RNA sequencing) and proteomic (sequential window acquisition of all theoretical mass spectra [SWATH-MS]) profiling of dorsal and ventral hippocampus in mice. We used three different acute stressors (novelty, swim, and restraint) to assess the impact of stress on both regions., Results: We demonstrated that both hippocampal regions display radically distinct molecular responses and that the ventral hippocampus is particularly sensitive to the effects of stress. Separately analyzing these structures greatly increased the sensitivity to detect stress-induced changes. For example, protein interaction cluster analyses revealed a stress-responsive epigenetic network around histone demethylase Kdm6b restricted to the ventral hippocampus, and acute stress reduced methylation of its enzymatic target H3K27me3. Selective Kdm6b knockdown in the ventral hippocampus led to behavioral hyperactivity/hyperresponsiveness., Conclusions: These findings underscore the importance of considering dorsal and ventral hippocampus separately when conducting high-throughput molecular analyses, which has important implications for fundamental research as well as clinical studies., (Copyright © 2018 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

Objective: With the use of multiple endoscopic endonasal surgical corridors, extended endoscopic endonasal approaches (EEEAs) are now being used to treat a wide range of ventral skull base lesions. Our aim was to present our experience with EEEAs to the ventral skull base lesions., Patients and Methods: The study group consisted of 106 patients (57 men and 49 women) who underwent surgery for skull base lesions using EEEAs from 2010 to 2017. The EEEA was most commonly used for giant pituitary macroadenomas, sinonasal malignancies, cerebrospinal fluid (CSF) leaks, meningiomas, craniopharyngiomas, and fibro-osseous lesions. Four different approaches were used including transtuberculum-transplanum, transethmoidal-transcribriform, transclival, and transmaxillary-transpterygoidal., Results: The overall gross total resection (GTR) rate for these diverse pathologies was 75.0% in 88 patients (excluding the operations performed for non-neoplastic pathologies). GTR was achieved in 100%, 77.8%, 75%, 75%, 72.2%, 62.5%, 60% of fibro-osseous lesions, giant/large pitutary adenomas, meningiomas, esthesioneuroblastomas, sinonasal malignancies, craniopharyngiomas, and chordomas, respectively. The overall rate of improvement in visual fields was 86%. The overall rate of CSF leak was 8.4%. Other surgical complications included intracerebral hematoma and tension pneumocephalus. The mortality rate was 0.9%., Conclusion: EEEA is a safe, well-tolerated and effective surgical treatment modality in the management of ventral skull base lesions. It should be performed with close interdisciplinary collaboration. Appropriate case selection is mandatory. However, despite improved reconstruction techniques, postoperative CSF leakage still remains a challenge., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Introduction: Abdominoplasty procedures sometimes reveal the presence of ventral hernias (umbilical or trocar-site hernias). Our objective is then to deal with the excess abdominal skin and fat tissue at the same time as the ventral hernia. This can be done with a single surgical procedure combining abdominoplasty with umbilical transposition and laparoscopic ventral hernia repair (LVHR) with mesh. The main objective of our study is to assess the outcome of the combined procedure of abdominoplasty and LVHR with mesh, compared to abdominoplasty alone., Materials and Methods: A retrospective single-centre cohort study was conducted, including patients operated on with the combined method (ABDO-LVHR group) and patients who underwent abdominoplasty alone (ABDO group). We noted major and minor complications, with infection issues as our main concern., Results: We included 15 patients in the ABDO-LVHR group and 30 in the ABDO group. The results show no statistically significant difference for infectious complications in the ABDO-LVHR group compared to the ABDO group (20% vs 3.3%; P=0.100). There was no instance of complete umbilical necrosis. Other major and minor complications occurred at the rates typically described in the literature without difference between the two groups., Conclusion: There was no significant difference between our two groups in terms of infectious complications. LVHR carried out at the same time as abdominoplasty with umbilical transposition is a positive combination of procedures. Further studies are necessary to confirm that the risk in terms of infectious complications is no higher than for abdominoplasty alone., Level of Evidence: III., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

Objective: There are controversies about the benefits of prophylactic antibiotics in the prevention of postoperative surgical site infection (SSI) in mesh herniorrhaphy for a long time. This study aimed to evaluate the effectiveness and efficacy of systemic prophylactic cefazolin in prevention of wound infection in various types of hernia repair with mesh materials., Methods: This is a prospective randomized control study. We evaluated wound infection rates in 395 patients with various kinds of hernia who underwent elective mesh repair using polypropylene mesh from 2007 to 2011. A total of 237 (60.0%) patients received prophylactic cefazolin (study group) and the remaining 158 (40.0%) patients did not receive any prophylactic antibiotics (control group). Patients were followed for infection at the following periods after the operation by an independent surgeon: 10 days, 30 days, 12 months, and then annually for at least 2 years., Results: Eight (2.03%) patients had infection in the site of surgery [2 (1.27%) in the control group and 6 (2.53%) in the study group]. The distribution of infection was not significantly different between the two groups (p = 0.364). The superficial infections were managed by drainage and irrigation. One patient from the study group developed deep SSI and was readmitted and subsequently received antibiotic therapy, drainage, and debridement., Conclusion: Preoperative administration of single-dose cefazolin for prosthetic hernia repairs did not markedly decrease the risk of wound infection. Our results do not support the use of cefazolin as a prophylactic antibiotic for various kinds of abdominal wall hernia repair with mesh., (Copyright © 2015. Published by Elsevier Taiwan.)

Developmental fields are subdivided into lineage-restricted cell populations, known as compartments. In the eye imaginal disc of Drosophila, dorso-ventral (DV) lineage restriction is the primary event, whereas antero-posterior compartment boundary is the first lineage restriction in other imaginal discs. The Iroquois complex (Iro-C) genes function as dorsal selectors and repress the default, ventral, identity in the eye-head primordium. In Iro-C mutant clones, change of the dorsal identity to default ventral fate leads to generation of ectopic DV boundary, which results in dorsal eye enlargement, and duplication of ventral appendages like antenna and maxillary palp. Similar phenotypes were observed in heads with defective proventriculus (dve) mutant clones. Here, we show that the homeobox gene dve is a downstream effector of Iro-C in the dorsal head capsule (vertex) specification and represses the ventral (antennal) identity. Two homeodomain proteins Distal-less (Dll) and Homothorax (Hth) are known to be determinants of the antennal identity. Ectopic antenna formation in heads with dve mutant clones was associated with ectopic Dll expression and endogenous Hth expression in the vertex region. Interestingly, dve Dll double mutant clones could also induce ectopic antennae lacking the distal structures, suggesting that the Dve activity is crucial for repressing inappropriate antenna-forming potential in the vertex region. Our results clearly indicate that not only the activation of effector genes to execute developmental program but also the repression of inappropriate program is crucial for establishment of the organ identity., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

This study investigates structural connectivity between left fronto-parietal brain regions that were identified in a previous fMRI study which used different linguistic manipulation tasks. Diffusion-weighted images were acquired from 20 volunteers. Structural connectivity between brain regions from the fMRI study was computed using probabilistic fiber tracking. For suprasegmental manipulation, left inferior parietal lobule (IPL) and left inferior frontal gyrus (IFG), pars opercularis, were connected by a dorsal pathway via the arcuate fascicle and superior longitudinal fascicle III. For segmental manipulation, left IPL and IFG, pars triangularis, were connected by a ventral pathway via the middle longitudinal fascicle and the extreme capsule. We conclude that the dorsal pathway provides a route for mapping from phonological memory in IPL to the inferior frontal articulatory network while the ventral pathway could facilitate the modulation of phonological units based on lexical-semantic aspects, mediate the complexity of auditory objects and the unification of actor-event schemata., (Copyright © 2013 Elsevier Inc. All rights reserved.)