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Bifenthrin (BF), a widely used pyrethroid pesticide in farming, lacks highly sensitive and selective sensors despite its extensive application. Ruthenium complexes are very effective for selective sensing applications but suffer from structural instability at elevated conditions, electrochemical activity, and the use of costly electrolytes. This work improves their electrochemical activity and mechanical strength by incorporating silver nanowires and replacing the costly electrolyte with abundant KCl + PBS, resulting in enhanced signal performance. Herein, a ruthenium complex containing composite film was immobilized on a platinum (Pt) electrode using Langmuir Blodgett technique. The fabricated sensor has been characterized by differential pulse voltammetry (DPV) based electrochemical technique. The BF pesticide sensing parameters, including the limit of detection (LOD), linear range (LR), and sensitivity, were evaluated using SWV, DPV, and CV techniques. Among these, the DPV technique demonstrated the best performance, achieving a sensitivity of 0.648 μA cm -2 μM -1 , a LR of 1-10 μM, and a LOD of 1 μM. The relative standard deviation (RSD) values using DPV are found to be 6.3% (repeatability study), 3% (reproducibility study), 8% (metal ion interference), 5% (organic species interference), and 2% (real sample study), which are much lesser than the World Health Organization (WHO) recommendation of RSD value on the pesticide ( i.e. 20%). The BF sensor demonstrated a selectivity of 2× difference of peak height response compared to similar pesticides. The reported pesticide sensor will open new options for sensor research using metal complex-based LB film nanocomposite., Competing Interests: The authors declare that there is no competing interest., (This journal is © The Royal Society of Chemistry.)

Paper-based sensors or paper-based analytical devices (PADs) have recently emerged as the cost-efficient, and portable, on-site detection tools for various biological and environmental analytes. However, paper-based sensors often suffer from poor selectivity. Here, a single-step paper-based flexible sensor platform has been developed for the on-site detection of paraquat (PQ) pesticide in real samples, utilizing chitosan and citrate-capped silver nanoparticles integrated with a flexible paper. The nanocomposite paper film was thoroughly characterized using UV-visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). The composite paper platform demonstrated a color change with a reaction time within a few minutes (6-7 min) in the presence of PQ pesticide. The trace level PQ pesticide has been detected with a limit of detection (LOD) of 10 μM and a linear range (LR) of 10-100 μM. The sensor shows 3× more selective signal towards PQ pesticide compared to other similar pesticides. The relative standard deviation (RSD) was found to be 5% for repeatability, 4% for reproducibility, 2% for interference, and 3.5% for real sample analysis, indicating high precision sensing and within the WHO limit of RSD (20%). The present work will open up new avenues for the advancements in flexible paper sensors; cost-effective, portable, on-site sensors, and sustainable device development., Competing Interests: The authors have no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

Background and Objectives: Atlantoaxial dislocation (AAD) poses a complex surgical challenge. Surgical approaches vary for reducible and irreducible cases. Challenges persist in reducing the atlantodental interval, especially in cases with oblique or vertical C1-C2 joints. The Rocker instrument (MJ Surgical), a less-explored technique, seeks to simplify instrumentation, reduce complexity, and enhance translation and retroflection reduction of AAD., Methods: This prospective observational study was conducted from January 2022 to July 2023 at a tertiary neurosurgical center. Inclusion criteria covered all age groups with AAD, with or without basilar invagination. Exclusions included medically unstable patients and severe osteoporotic spine conditions. Preoperative assessments included dynamic X-rays, magnetic resonance imaging, and computed tomography scans. The Rocker technique was used, and patients were followed up for 6 to 12 months., Results: Fifty-five patients (30 males, 25 females) underwent surgery. The mean age was 40.41 ± 15.01 years. Successful Rocker technique application was observed in 53 cases. Functional outcomes, assessed using Modified Ranawat grading, showed improvement postoperatively. Radiological outcomes revealed a significant reduction in the anterior atlantodental interval (7.21 ± 0.94 to 2.98 ± 0.78). Basilar invagination was reduced in all cases, whenever present. The technique exhibited versatility, applicability in various joint orientations, and cost-effectiveness., Conclusion: The Rocker technique is a safe and effective alternative for managing both reducible and irreducible AADs, with or without basilar invagination. It simplifies the reduction process, offering advantages over established techniques. Further trials, especially in rotational deformities, are warranted for validation., (Copyright © Congress of Neurological Surgeons 2024. All rights reserved.)

Maleic acid functionalized boron nitride nanosheets (BNNS-MA)/Na-Alginate composite with enhanced mechanical, UV-shielding and antioxidation properties have been fabricated for the first time by solvent evaporation from a homogeneous aqueous dispersion of BNNS-MA/Na-Alginate composite solution. The composite fabrication was driven by homogenous nano-integrations and chemistry of compatibilization of BNNS-MA with Na-Alginate through H-bonding interactions between -COOH functional group of BNNS-MA and -OH, -COONa groups of Na-Alginate. The BNNS-MA/Na-Alginate composites show significant enhancement of mechanical, UV-blocking and antioxidant properties compared to the Na-Alginate. Integrating only 1 wt% BNNS-MA improved the UV-blocking, tensile strength, and antioxidant properties of Na-Alginate film by 99.1%, 73% and 60.3%, respectively. Overall, our findings of BNNS-MA integrated Na-Alginate composite films with improved physical, mechanical, UV shielding, and antioxidant functionalities is very promising to open new insight in the field of transparent UV-protected biopolymer film for consumer products, packaging, cosmetics, and engineering applications., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Rama Layek reports financial support was provided by Kollin säätiö funding for biorefinery programme LUT University, Lahti campus., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Competing Interests: None

The major challenges of hyaluronic acid-based bioinks in extrusion-based three-dimensional bioprinting are poor printability and low printing accuracy. To tackle the challenges, we developed a bioink in which two components are blended: gallic acid-functionalized hyaluronic acid (HAGA) and hyaluronic acid methacrylate (HAMA). In the precursor phase, the blend's HAGA component enables pH-dependent viscosity modulation that results in improved injectability and printability at physiological temperature. Postprinting, the blend's HAMA component is photocrosslinked to create a true hydrogel with a complementary network of both HAGA and HAMA. The ready structures of the HAGA-HAMA hydrogel showed sufficient printing quality and accuracy compared to plain HAMA. The blend also displayed enhanced viscoelastic properties and stable swelling behavior. In addition to the pH tunability, the HAGA component also imparted tissue adhesion and antioxidant activity. This bioink has the potential to be printed directly on an infected wound site due to its adhesiveness to tissue and dimensional stability in situ.

Competing Interests: None

The printability of a photocross-linkable methacrylated gelatin (GelMA) bioink with an extrusion-based 3D bioprinter is highly affected by the polymer concentration and printing temperature. In this work, we developed a gallic acid (GA)-functionalized GelMA ink to improve the printability at room and physiological temperatures and to enable tissue adhesion and antioxidant properties. We introduced a sequential cross-linking approach using catechol-Fe 3+ chelation, followed by photocross-linking. The results show that the ink formulation with 0.5% (w/v) Fe 3+ in GelMA (30% modification) with 10% GA (GelMA30GA-5Fe) provided the optimum printability, shape fidelity, and structural integrity. The dual network inside the printed constructs significantly enhanced the viscoelastic properties. Printed cylinders were evaluated for their printing accuracy. The printed structures of GelMA30GA-5Fe provided high stability in physiological conditions over a month. In addition, the optimized ink also offered good tissue adhesion and antioxidant property. This catechol-based sequential cross-linking method could be adopted for the fabrication of other single-polymer bioinks.

Purpose: Injection of intra-articular medicaments is an accepted therapy for temporomandibular joint disorders (TMDs). This study compares the efficacy of arthrocentesis followed by platelet-rich plasma (PRP) as compared to hyaluronic acid (HA) injections for TMDs unresponsive to conservative therapy. PRP injection following arthrocentesis was hypothesized to be better compared to arthrocentesis alone or when combined with HA injection., Methods: Forty-seven patients with TMDs enrolled in an RCT were randomly assigned to three groups: Group A-PRP, Group B-HA or Group C-control group of arthrocentesis alone. Pre-operative evaluation and post-operative changes at 1-, 3-, 6-month intervals were assessed for improvement in pain, maximum mouth opening, joint sounds and excursive movements. Statistical significance was set at P value < 0.05., Results: Post-operative joint sounds were present in three out of 16 patients in Group A; six out of 15 patients in Group B and eight out of 16 patients in Group C at 6-month follow-up. For the remaining outcome variables, no statistical difference between groups was observed., Conclusion: Both medicaments produced significant clinical improvements when compared to the control group. When comparing PRP against HA, none showed superiority over the other. Clinical trial registration number : CTRI/2019/01/017076., Competing Interests: Conflict of interestThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© The Association of Oral and Maxillofacial Surgeons of India 2021.)

Innovative scaffold designs that modulate the local inflammatory microenvironment through favorable macrophage polarization and suppressing oxidative stress are needed for successful clinical translation of regenerative cell therapies and graft integration. We herein report derivation of a hydrazone-crosslinked gallol functionalized hyaluronic acid (HA-GA)-based hydrogel that displayed outstanding viscoelastic properties and immunomodulatory characteristics. Grafting of 6% gallol (GA) to a HA-backbone formed an interpenetrative network by promoting an additional crosslink between the gallol groups in addition to hydrazone crosslinking. This significantly enhanced the mechanical stability and displayed shear-thinning/self-healing characteristics, facilitated tissue adhesive properties to porcine tissue and also displayed radical scavenging properties, protecting encapsulated fibroblasts from peroxide challenge. The THP-1 human macrophage cell line or primary bone-marrow-derived murine macrophages cultured within HA-GA gels displayed selective polarization to a predominantly anti-inflammatory phenotype by upregulating IL4ra, IL-10, TGF-β, and TGF-βR1 expression when compared with HA-HA gels. Conversely, culturing of pro-inflammatory activated primary murine macrophages in HA-GA gels resulted in a significant reduction of pro-inflammatory TNF-α, IL-1β, SOCS3 and IL-6 marker expression, and upregulated expression of anti-inflammatory cytokines including TGF-β. Finally, when the gels were implanted subcutaneously into healthy mice, we observed infiltration of pro-inflammatory myeloid cells in HA-HA gels, while immunosuppressive phenotypes were observed within the HA-GA gels. Taken together these data suggest that HA-GA gels are an ideal injectable scaffold for viable immunotherapeutic interventions. STATEMENT OF SIGNIFICANCE: Host immune response against the implanted scaffolds that are designed to deliver stem cells or therapeutic proteins in vivo significantly limits the functional outcome. For this reason, we have designed immunomodulatory injectable scaffolds that can favorably polarize the recruited macrophages and impart antioxidant properties to suppress oxidative stress. Specifically, we have tailored a hyaluronic acid-based extracellular matrix mimetic injectable scaffold that is grafted with immunomodulatory gallol moiety. Gallol functionalization of hydrogel not only enhanced the mechanical properties of the scaffold by forming an interpenetrating network but also induced antioxidant properties, tissue adhesive properties, and polarized primary murine macrophages to immunosuppressive phenotype. We believe such immunoresponsive implants will pave the way for developing the next-generation of biomaterials for regenerative medicine applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare no conflict of interest., (Copyright © 2022. Published by Elsevier Ltd.)

Background: Lumboperitoneal shunt is a known procedure for communicating hydrocephalus. Being an extracranial procedure, it can also be utilized in normal-sized ventricles., Objective: To report our experience of lumboperitoneal shunt done with a minimal follow-up of 12 months with an emphasis on patient selection, technique, and complication avoidance., Methods: This was a retrospective analysis of patients who underwent LP shunt during October 2014-October 2019 at the authors' institute. Inclusion criteria were patients with communicating hydrocephalus due to tubercular meningitis, normal pressure hydrocephalus, idiopathic intracranial hypertension, and postoperative refractory cerebrospinal fluid leaks. Data were collected for demographics, Glasgow coma scale and Glasgow outcome scale, vision, gait, memory, urinary incontinence, failed attempts, and complications., Results: A total of 426 patients underwent the LP shunt procedure. The commonest indication was tubercular meningitis followed by idiopathic intracranial hypertension and normal pressure hydrocephalus. Age ranged from 16 to 72 years. There were 255 male and 171 female patients. The mean follow-up was 41 ± 8 months. Overall, 301 patients (70.6%) had neurological improvement. Shunt-related complications occurred in 112 (26.29%) patients, of which shunt block was the commonest. Other complications were infection in 17 (3.9%) patients and extrusion in four (0.9%) patients. Transient postural headache was seen in 46 (10.7%) patients, which gradually improved., Conclusion: Lumboperitoneal shunt was found to be a safe and effective treatment in appropriately selected communicating hydrocephalus patients. A meticulous technique reduces the complication rate., Competing Interests: None

Anti-inflammatory drugs such as dexamethasone (DEX) are commonly administered to cancer patients along with anticancer drugs, however, the effect of DEX on human cancers is poorly understood. In this article, we have tailored self-assembled nanoparticles derived from hyaluronic acid (HA) wherein, anti-inflammatory DEX was used as a hydrophobic moiety for inducing amphiphilicity. The HA-DEX micelles were subsequently loaded with chemotherapeutic agent, doxorubicin (DOX) (HA-DEX-DOX) and was utilized to deliver drug cargo to human cancer cells expressing different levels of CD44 receptors. We found that DEX suppressed the cytotoxicity of DOX in HCT116, while it synergistically enhanced cytotoxicity in MCF-7 cells. When we tested DOX and HA-DEX-DOX in an ex-vivo human whole blood, we found activation of complement and the coagulation cascade in one group of donors. Encapsulation of DOX within the nanoparticle core eliminated such deleterious side-effects. The HA-DEX-DOX also polarized bone-marrow-derived anti-inflammatory M2 macrophages, to pro-inflammatory M1 phenotype with the upregulation of the cytokines TNF-α, iNOS and IL-1β., (Copyright © 2020. Published by Elsevier Ltd.)

For modern tissue engineering, we need not only develop new hydrogels but also suitable processing methods for them. Polypeptides and polysaccharides are potential candidates because they can be methacrylated, processed before photocross-linking, and yielded into hydrogels with given shape and form. In this study, we successfully methacrylated collagen, gelatin, hyaluronan, and alginate to 30 and 60% degree of modification. We studied methacrylated compositions (i.e., precursors) to investigate their processability. The precursors of collagen and gelatin with 60% methacrylation exhibited suitable yield stress, shear-thinning properties, and fiber-forming capability for injecting and 3D bioprinting. On the contrary, the 30% methacrylated precursors had properties suitable for casting purposes. Our study also showed that the mechanical properties of hydrogels corresponded to the used photocross-linking conditions and the degree of modification. These results underline the importance of tunability of the precursors and resulting hydrogels according to the specific fabrication method and tissue engineering application.

Regeneration of a severely damaged cornea necessitates the delivery of both epithelium-renewing limbal epithelial stem cells (LESCs) and stroma-repairing cells, such as human adipose-derived stem cells (hASCs). Currently, limited strategies exist for the delivery of these therapeutic cells with tissue-like cellular organization. With the added risks related to suturing of corneal implants, there is a pressing need to develop new tissue adhesive biomaterials for corneal regeneration. To address these issues, we grafted dopamine moieties into hydrazone-crosslinked hyaluronic acid (HA-DOPA) hydrogels to impart tissue adhesive properties and facilitate covalent surface modification of the gels with basement membrane proteins or peptides. We achieved tissue-like cellular compartmentalization in the implants by encapsulating hASCs inside the hydrogels, with subsequent conjugation of thiolated collagen IV or laminin peptides and LESC seeding on the hydrogel surface. The encapsulated hASCs in HA-DOPA gels exhibited good proliferation and cell elongation, while the LESCs expressed typical limbal epithelial progenitor markers. Importantly, the compartmentalized HA-DOPA implants displayed excellent tissue adhesion upon implantation in a porcine corneal organ culture model. These results encourage sutureless implantation of functional stem cells as the next generation of corneal regeneration., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Fractures of the mandibular condyle lead to displacement of the condyle and loss of the height of the ramus. A retromandibular approach is the most commonly used for open reduction and internal fixation (ORIF) of such fractures. We aimed to compare the complications associated with a retromandibular transparotid approach with a retromandibular transmasseteric anterior parotid (TMAP) approach for their management. Thirty patients were randomly selected into two groups (15 in each): Group A comprised the retromandibular transparotid approach and Group B the retromandibular TMAP. The variables evaluated were: operating time, facial nerve injury, occurrence of Frey syndrome, and sialocoele at one week, four weeks, three months, and six months. The mean (SD) age in group A and B was 33.93 (17.97) years and 33.53 (16.15) years, respectively, and there were 28 men and two women. Mean (SD) exposure time in the transparotid approach was 26.93 (5.19) minutes and 25.4 (8.35) minutes in the TMAP approach. The incidence of facial nerve injury was 2/15 patients in the transparotid group and 3/15 in the TMAP group, all of which resolved within six months. The incidence of sialocoele was 2/15 in the transparotid group. The results did not show any significant difference in complications between the two approaches, but the retromandibular transparotid approach provided straight-line access in fractures of the condylar neck, with fewer incidences of nerve injury. The anterior parotid approach, on the other hand, provided easier access for fractures that were medially dislocated or of the condylar base but had an increased incidence of facial nerve injuries., (Copyright © 2019 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Introduction:  Although the indications for endoscopic procedures have increased in recent times, there are also some limitations. This review discusses the practical points to prevent and treat complications in microendoscopic spine surgery., Material and Methods:  A literature search was conducted for the relevant articles after a topic search on PubMed, Google Scholar, and Medline. The review is based on the experience of 1,574 spinal endoscopic procedures performed by the senior author., Results:  Advantages of endoscopic surgery include better visualization, panoramic vision, and the ability to work around corners. Limitations with endoscopic procedures include proximal blind areas, obstruction in instrument handling due to a narrow corridor, disorientation, frequent lens fogging, loss of depth perception, and difficulty in achieving hemostasis, leading to complications and longer operative time during the learning curve., Conclusion:  Surgeons need to learn endoscopic skills in addition to microsurgical ones to perform microendoscopic procedures properly. Attending live workshops, watching operative videos, visiting various departments, watching an experienced and accomplished endoscopic surgeon, proper case selection, a multidisciplinary team approach, practicing on models, hands-on cadaveric workshops, laboratory training, and simulators can improve results and shorten the learning curve., Competing Interests: None declared., (Georg Thieme Verlag KG Stuttgart · New York.)

Although most of the cases of atlanto-axial dislocation (AAD) and basilar invasion can be managed by posterior approaches in the recent times, anterior decompression with stabilization is required in selected patients who persist with irreducible AAD even after manipulation of the C1-C2 facet joint under general anesthesia. A single stage endoscopic trans-oral decompression and stabilization can be used in such patients. It has not been described so far to the best of authors' knowledge. This is indicated in irreducible AAD with the mandibular angle lying below the C2-C3 disc space. It is not a proper choice when the mandibular angle is above the C2-C3 disc space, there is involvement of the facet joint by trauma or any other pathologies, and if a posterior compression at the cervicomedullary junction persists. All patients should undergo pre-operative radiographs, computed tomography (CT) scan and magnetic resonance imaging with angiogram of the cranio-vertebral region. Utilizing this technique, an intra-operative satisfactory reduction of the dislocation with C1-C2 stabilization could be achieved in 3 patients, and 7 required an additional odontoid excision. Post- operative plain radiographs should be performed to assess for C1- C2 alignment and fusion at 3 and 12 months after surgery. All 10 patients of our series had an irreducible AAD and two had an additional basilar invasion. All patients improved from the pre-operative Ranawat grade 3A (n = 8) and 3B (n = 2) to post-operative grade 1 (n = 9) and 2 (n = 1) at a 3-12- month follow-up assessment. The average duration of the procedure and blood loss was 145 minutes and 75 ml, respectively. Endoscopic trans-oral single stage decompression and stabilization seems to be an effective and safe alternative in selected patients with AAD and basilar invasion., Competing Interests: None

Introduction: Although there are controversies about the optimal management of spontaneous intracerebral hemorrhage (ICH), benefits of endoscopic procedures in ICH have been reported. This study is aimed to evaluate the result of 270 patients undergoing endoscopic treatment of ICH., Methods: This was a retrospective study from July 2008 to June 2017. All procedures were done with the endoscopic technique using a tubular retractor. Patients with the hematoma volume between 30 to 80 ml, with the Glasgow Coma Scale (GCS) between 5 to 14, and evidence of severe mass effect, were included in the study., Results: The average stay in the intensive care unit was 6 days (range 1-17 days). The median pre-operative midline shift of 8.3 mm was reduced to 2.7 mm after surgery. The average hematoma removal ratio, the duration of surgery, and the blood loss was 90%, 90 min, and 60 ml, respectively. There was improvement in the average pre-operative GCS from 9.4 to 11.3 at seventh post-operative day. The post-operative mortality rate was 10.7%. A good outcome was observed in 71% patients at 6 months after surgery. Larger the volume of hematoma, more the operative time, more the pre-operative midline shift, and poorer the GCS, significantly higher was the association with mortality. The patients with a better pre-operative GCS were associated with a better Glasgow Outcome Score. The follow-up period ranged from 7 to 115 months., Conclusion: Endoscopic surgery with the help of a tubular retractor was effective and safe. It allowed for a good visualization of the hematoma and the surrounding brain, and helped in proper hemostasis. The hematoma may also be removed with the help of the microscope and the tubular retractor, in case any difficulty during the endoscopic technique is encountered., Competing Interests: There are no conflicts of interest

Green chemistry approaches for designing therapeutically significant nanomedicine have gained considerable attention in the past decade. Herein, we report for the first time on anticancer potential of phytogenic platinum nanoparticles (PtNPs) and palladium nanoparticles (PdNPs) using a medicinal plant Gloriosa superba tuber extract (GSTE). The synthesis of the nanoparticles was completed within 5 hours at 100°C which was confirmed by development of dark brown and black colour for PtNPs and PdNPs, respectively, along with enhancement of the peak intensity in the UV-visible spectra. High-resolution transmission electron microscopy (HRTEM) showed that the monodispersed spherical nanoparticles were within a size range below 10 nm. Energy dispersive spectra (EDS) confirmed the elemental composition, while dynamic light scattering (DLS) helped to evaluate the hydrodynamic size of the particles. Anticancer activity against MCF-7 (human breast adenocarcinoma) cell lines was evaluated using MTT assay, flow cytometry, and confocal microscopy. PtNPs and PdNPs showed 49.65 ± 1.99% and 36.26 ± 0.91% of anticancer activity. Induction of apoptosis was most predominant in the underlying mechanism which was rationalized by externalization of phosphatidyl serine and membrane blebbing. These findings support the efficiency of phytogenic fabrication of nanoscale platinum and palladium drugs for management and therapy against breast cancer.

Objective: To report our experience of endoscopic disc removal by anterior approach for management of cervical myelopathy in 210 patients., Methods: A retrospective study of 187 cases of single- and 23 cases of double-level disc disease was performed. Cases of myelopathy with or without unilateral or bilateral radiculopathy and unilateral radiculopathy with either soft or hard disc prolapse were included. Patients with ≥3 disc levels, unstable spine, infections, trauma, significant posterior compression, congenital canal stenosis, disc extending more than half the vertebral body height, and prior surgery at the same level were excluded., Results: C5-6 (n = 119 patients), C6-7 (n = 58 patients), C4-5 (n = 49 patients), C3-4 (n = 6 patients), and C2-3 (n = 1 patient) levels were represented. Visual analog scale and Nurick grading system were used to assess severity of neck and arm pain and functional outcomes, respectively. Preoperative mean visual analog scale scores for arm and neck pain were 6.7 and 3.2, respectively, which improved to 1.7 and 1.1 at 3 months after surgery. The average preoperative Nurick grade improved from 2.64 to 0.81 at 6 months postoperatively. Follow-up was 6-54 months., Conclusions: Endoscopic anterior discectomy (disc preserving surgery) is an effective and safe alternative in cervical disc disease. Although there was reduction in disc height, clinical outcome was good at an average 29 months of follow-up. Long-term follow-up is required to assess any progressive disc degeneration and clinical results., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Although most surgeons are using endoscopy as an adjunct to microscopy in microvascular decompression, a full endoscopic technique is less commonly performed. The present study is aimed to evaluate results of 230 patients of endoscopic vascular decompression., Methods: A retrospective study was carried out in a tertiary care hospital. Patients with typical neuralgia, with or without preoperatively detected vascular compression, were advised to undergo vascular decompression., Results: Maxillary and mandibular division were involved in 116 and 93 patients, respectively. Superior cerebellar (n = 174) artery was most common vascular conflict followed by anterior inferior cerebellar artery (n = 96). Tortuous basilar artery and small veins were possible causes of neuralgia in 1 and 2 patients, respectively. Single- and double-vessel conflict were observed in 173 and 50 patients, respectively. The compressing vessel was placed anterior to the trigeminal nerve in 39 patients. An arterial loop was in contact with the nerve, producing grooving, and displacing the nerve in 215, 35, and 21 patients, respectively. Complete, satisfactory, and no relief of pain were observed in 204 (88.7%), 11 (5.8%), and 15 (6.5%) patients, respectively. Recurrence was observed in 25 patients at an average follow-up of 60 months. Temporary complications included trigeminal dysesthesia, vertigo, facial paresis, CSF leak, and reduced hearing in 9, 8, 8, 7, and 3 patients, respectively., Conclusion: Endoscopic vascular decompression is a safe and efficient alternative technique to endoscopic assisted microvascular decompression provided surgeon is experienced in endoscopic surgery. It is helpful in identification of all offending vessels including the double vessel, and anterior compression without brain and nerve retraction., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Introduction:  Several different surgical techniques have been used in the treatment of patients with symptomatic Arnold-Chiari malformation type 1 (ACM-1) with or without syrinx. Endoscope-assisted decompression of the posterior fossa has been found to be safe and effective. We report our initial experience of endoscopic management of ACM-I., Material and Methods:  This was a prospective study of 15 symptomatic patients. Pre- and postoperative clinical status and computed tomography and magnetic resonance imaging findings were recorded. Suboccipital bone of ∼ 3 cm distance from the foramen of magnum and posterior arch of atlas was removed. Partial splitting of the dura mater with preservation of the inner portion and the arachnoid membrane was performed. Any change in axial and sagittal length of the syrinx, tonsillar ascension, shape of the tonsil tip, appearance of cerebrospinal fluid posterior to the tonsil, and formation of the cisterna magna were recorded. Patients with atlantoaxial instability, tethered cord, associated myelomeningocele, hydrocephalus, or elevated intracranial pressure were excluded., Results:  Age of patients ranged from 26 to 48 years. There were nine female patients. There were six patients with ACM-I without and nine with ACM-I with syrinx. Average pre- and postoperative Karnofsky performance score was 78 and 93, respectively. Average operative time was 130 minutes (110-190 minutes), and blood loss was 30 mL (20-180 mL). Follow-up ranged from 9 to 21 months., Conclusion:  Although the study is limited by the small number of patients with a short follow-up, endoscopic decompression in selected patients of ACM-I with or without syrinx with dural splitting was a safe and effective alternative to microsurgical treatment., Competing Interests: Disclosure The authors report no conflicts of interest in this work., (Georg Thieme Verlag KG Stuttgart · New York.)

Introduction  Endoscopic techniques are being used in lumbar disk disease and lumbar canal stenosis to decompress the spinal canal. The present study analyzed pre- and postoperative magnetic resonance imaging (MRI) measurements of the lumbar canal. Material and Methods  This was a prospective study of 30 lumbar levels. Patients < 18 years of age with unilateral compression, previous surgery at the same level, and spinal instability were excluded. Endoscopic posterior decompression was used. Pre- and postoperative MRIs of all the patients were performed. Anteroposterior (AP), transverse, interfacet diameter, canal surface area, and height and angle of the lateral recess were measured. Results  Mean ages of male and female patients were 42.1 ± 10.3 and 45.0 ± 9.9 years, respectively. Pathologies were at L4-L5, L5-S1, and L2-L3 levels in 16, 13, and 1 patient, respectively. There was significant improvement in AP diameter (4.75 ± 1.75 mm to 10.33 ± 2.11 mm), interfacet distance (12.70 ± 4.86 mm to 18.92 ± 3.53 mm), and canal surface area (76.45 ± 25.36 mm 2 to 187.13 ± 41.04 mm 2 ) after decompression. Significant improvement was noted in mean height and angle of lateral recess after surgery of both sides suggesting that effective decompression of the bilateral canal was possible using a unilateral approach. Most of the patients (90%) showed excellent and good improvement after surgery. Postoperative canal surface area and AP diameter in patients who did not have any pain after surgery or had pain requiring occasional medication was higher compared with patients who continued to complain of pain and required continuous pain medication. Conclusion  Although the number of patients was small with a short follow-up, the endoscopic technique was effective in improving AP diameter, interfacet distance, canal surface area, lateral recess height, and lateral recess angle, suggesting that an endoscopic technique using a unilateral approach is effective in bilateral decompression of neural elements., Competing Interests: Disclosure The authors report no conflicts of interest in this work., (Georg Thieme Verlag KG Stuttgart • New York.)

Introduction  Posterior midline laminectomy is associated with risks of postoperative instability, spinal deformity, extensive bilateral subperiosteal muscle stripping, partial or total facetectomy especially in foraminal tumor extension, increased cerebrospinal fluid leakage, and wound infection. Minimally invasive approaches with the help of a microscope or endoscope using hemilaminectomy have been found to be safe and effective. We report our initial experience of 18 patients using the endoscopic technique. Material and Methods  A retrospective study of intradural extramedullary tumors extending up to two vertebral levels was studied. Pre- and postoperative clinical status, magnetic resonance imaging was done in all patients. The Destandau technique was used, and resection of ipsilateral lamina, medial part of the facet joint, base of the spinous process, and undercutting of the opposite lamina was performed. Dura repair was done using an endoscopic technique. Fibrin glue was used to reinforce repair in the later part of the study. Results  The sagittal and axial diameter of tumor ranged from 21 to 41 mm and 12 to 18 mm, respectively. There were four cervical, two cervicothoracic, five thoracic, three thoracolumbar, and four lumbar tumors, respectively. All 18 patients improved after total excision of tumor. Average duration of surgery and blood loss was 140 minutes and 60 mL, respectively. Postoperative stay and follow-up ranged from 3 to 7 days and 9 to 24 months, respectively. Conclusion  Although the study is limited by the small number of patients with a short follow-up and is a technically demanding procedure, endoscopic management of intradural extramedullary tumors was an effective and safe alternative technique to microsurgery in such patients., (Georg Thieme Verlag KG Stuttgart · New York.)

Hydrocephalus is one of the commonest complications of tuberculous meningitis (TBM). It can be purely obstructive, purely communicating, or due to combinations of obstruction in addition to defective absorption of cerebrospinal fluid (CSF). Endoscopic third ventriculostomy (ETV) as an alternative to shunt procedures is an established treatment for obstructive hydrocephalus in TBM. ETV in TBM hydrocephalus can be technically very difficult, especially in acute stage of disease due to inflamed, thick, and opaque third ventricle floor. Water jet dissection can be helpful in thick and opaque ventricular floor patients, while simple blunt perforation is possible in thin and transparent floor. Lumbar peritoneal shunt is a better option for communicating hydrocephalus as compared to VP shunt or ETV. Intraoperative Doppler or neuronavigation can help in proper planning of the perforation to prevent neurovascular complications. Choroid plexus coagulation with ETV can improve success rate in infants. Results of ETV are better in good grade patients. Poor results are observed in cisternal exudates, thick and opaque third ventricle floor, acute phase, malnourished patients as compared to patients without cisternal exudates, thin and transparent third ventricle floor, chronic phase, well-nourished patients. Some of the patients, especially in poor grade, can show delayed recovery. Failure to improve after ETV can be due to blocked stoma, complex hydrocephalus, or vascular compromise. Repeated lumbar puncture can help faster normalization of the raised intracranial pressure after ETV in patients with temporary defect in CSF absorption, whereas lumbar peritoneal shunt is required in permanent defect. Repeat ETV is recommended if the stoma is blocked. ETV should be considered as treatment of choice in chronic phase of the disease in obstructive hydrocephalus.

Background Retraction of the overlying brain can be difficult without causing significant trauma when using traditional brain retractors with blades. These retractors may produce focal pressure and may result in brain contusion or infarction. Tubular retractors offer the advantage of low retracting pressure that is less likely to be traumatic. Low retraction pressure in the tubular retractor is due to the distribution of retraction force in all directions in a larger area. Material and Methods We conducted a retrospective study of 100 patients with deep-seated tumors operated on from January 2010 to December 2014. Tumor removal was accomplished with the help of a microscope and/or endoscope. Tubular brain retractors sizes 23, 18, and 15 mm were used. Folding of the tubular retractor after making a longitudinal cut allowed a small corticectomy. Larger retractor sizes were used in the earlier part of the study and in larger tumors. All the patients were evaluated postoperatively by computed tomography scan on the first postoperative day, and subsequent scans were done as and when needed. Any brain contusion or infarctions and the amount of tumor removal were recorded. Results A total of 74 patients had astrocytomas; 12, meningiomas; 4, colloid cyst of the third ventricle; 4, metastases; 4, primitive neuroectodermal tumor; 1, neurocytoma; and 1, ependymoma. Pure endoscopic excision without using a microscope was performed in 12 patients. Lesions were in the frontal (n = 34), parietal (n = 22), intraventricular (n = 16), basal ganglion or thalamic (n = 14), occipital (n = 10), and cerebellar (n = 4) areas. Total, near-total, and partial excision was achieved in 49, 29, and 22 patients, respectively. Use of a conventional retractor for excision of peripheral and superficial parts of a large tumor, small brain contusions, and technical failure were observed in 7, 4, and 1 patient, respectively. The low incidence of contusion may be partly due to the nonavailability of magnetic resonance imaging in the early postoperative period because of financial constraints. Conclusion Removal of deep-seated tumors was safe and effective using our simple tubular retractor. It also helped minimize bleeding during surgery. A tubular brain retractor and conventional retractor can be used to complement each other if required., (Georg Thieme Verlag KG Stuttgart · New York.)

N-Heterocyclic carbene-phosphine iridium complexes (NHC-Ir) were developed/found to be a highly reactive catalyst for N-monoalkylation of amides with alcohols via hydrogen transfer. The reaction produced the desired product in high isolated yields using a wide range of substrates with low catalyst loading and short reaction times.

Endoscopic neurosurgical techniques hold the potential for reducing morbidity. But they are also associated with limitations such as the initial learning curve, proximal blind spot, visual obscurity, difficulty in controlling bleeding, disorientation, and loss of stereoscopic image. Although some of the surgical techniques in neuroendoscopy and microsurgery are similar, endoscopy requires additional skills. A thorough understanding of endoscopic techniques and their limitations is required to get maximal benefit. Knowledge of possible complications and techniques to avoid such complications can improve results in endoscopic third ventriculostomy (ETV). The surgeon must be able to manage complications and have a second strategy such as a cerebrospinal fluid shunt if ETV fails. It is better to abandon the procedure if there is disorientation or a higher risk of complications such as bleeding or a thick and opaque floor without any clear visualization of anatomy. Attending live workshops, practice on models and simulators, simpler case selection in the initial learning curve, and hands-on cadaveric workshops can reduce complications. Proper case selection, good surgical technique, and better postoperative care are essential for a good outcome in ETV. Although it is difficult to make a preoperative diagnosis of complex hydrocephalus (combination of communicating and obstructive), improving methods to detect the exact type of hydrocephalus before surgery could increase the success rate of ETV and avoid an unnecessary ETV procedure in such cases., (Georg Thieme Verlag KG Stuttgart · New York.)

New quaternary indolizidine iminosugars, with hydroxymethyl group at the ring junction, namely, C-8a-hydroxymethyl-1-deoxycastanospermine congeners 1a, 2a, 3a and their 3-oxo analogs 1b, 2b, and 3b were synthesized by using intramolecular reductive aminocyclization/lactamization of d-mannose/D-glucose derived C5-γ-azido esters as a key step wherein both the rings of the indolizidine skeleton were built up in one pot following the cascade reaction pathway. The conformations ((5)C8 or (8)C5) of 1-3 were assigned on the basis of the (1)H NMR studies. All compounds were found to be potent inhibitors of various glycosidase enzymes with Ki and IC50 values in the micromolar/nanomolar concentration range and further substantiated by molecular docking studies. The effect of synthesized iminosugars 1-3 on the cytokine secretion of IL-4, IL-6, and IFN-γ was evaluated. All compounds were found to be TH1 bias increasing the TH1/TH2 cytokines ratio (IL-6 and IL-4) indicating their potency as immunostimulating agents. Our study suggests that immunomodulatory activity of indolizidine iminosugars can be tuned by minor structural/stereochemical alterations.

Isolates of Listeria monocytogenes (n = 932) isolated in Sweden during 1958-2010 from human patients with invasive listeriosis were characterized by serotyping and pulsed-field gel electrophoresis (PFGE) (AscI). Of the 932 isolates, 183 different PFGE types were identified, of which 83 were each represented by only one isolate. In all, 483 serovar 1/2a isolates were distributed over 114 PFGE types; 90 serovar 1/2b isolates gave 32 PFGE types; 21 serovar 1/2c isolates gave nine PFGE types; three serovar 3b isolates gave one PFGE type; and, 335 serovar 4b isolates gave 31 PFGE types. During the 1980s in Sweden, several serovar 4b cases were associated with the consumption of European raw soft cheese. However, as cheese-production hygiene has improved, the number of 4b cases has decreased. Since 1996, serovar 1/2a has been the dominant L. monocytogenes serovar in human listeriosis in Sweden. Therefore, based on current serovars and PFGE types, an association between human cases of listeriosis and the consumption of vacuum-packed gravad and cold-smoked salmon is suggested.

Background: The endoscopic excision of the odontoid process in irreducible atlantoaxial dislocation (AAD) can be achieved by transnasal, transoral, and transcervical approaches. Endoscopic transoral technique has been found to be effective and safe. It avoids palatal splitting or prolonged retraction. We are reporting our experience of 34 cases. The relevant literature is reviewed., Material and Methods: This was a prospective study of 34 patients treated during the past 5 years. Detailed history was taken and a thorough physical examination was made to record preoperative status. X-ray cervical spine lateral view (in neutral, flexion, and extension), anteroposterior (AP), and transoral view for the odontoid process were taken. Preoperative computed tomography (CT) and magnetic resonance imaging (MRI) scans and postoperative CT scans were done in all cases. Postoperative status at 1, 6, and 12 months was recorded., Results: Age ranged from 15 to 56 years. There were 22 male and 12 female patients. Symptom duration ranged from 6 to 18 months.Preoperatively, there were 26 and 8 patients in Ranawat grades 3A and 3B, respectively. Five patients had tenth cranial nerve paresis. There were 23, 10, and 1 cases of AAD, AAD with basilar invasion, and tuberculosis, respectively. Palatal splitting was not required in any of the cases. All patients improved after surgery. No deaths occurred. One patient had cerebrospinal fluid (CSF) leak, which stopped after external lumbar drainage. Follow-up ranged from 12 to 65 months., Conclusion: Endoscopic transoral odontoidectomy is a safe and effective alternative technique for odontoid excision. It can be performed in patients with small oral openings. Angled scopes improved exposure of clivus and palatal splitting was not required even in basilar invasion., (Georg Thieme Verlag KG Stuttgart · New York.)

Aim: Burr-hole craniostomy is the most efficient and safe choice for surgical drainage of chronic subdural hematoma (CSDH). Although the twist-drill drainage is also relatively safe and time-saving, it carries the risk of inadequate drainage, brain penetration and hematoma formation. Our modified technique helps in avoiding bleeding and brain penetration., Material and Methods: The preferred sites for twist drill were the most curved parts on the cranium. Normal drilling at about 90 degree angle was done on the most curved surfaces while it was at about 60 degree angles on flat surface. This angled drilling and the curved guide wire (hooked in the distal blind end of infant feeding tube), helped to guide infant feeding tube in the hematoma cavity. Dura matter was coagulated using insulated wire., Results: There was no procedure related hematoma, brain penetration and mortality in any of the 50 patients managed by the modified technique. Infant feeding tube was properly positioned in all the cases. Burr hole evacuation was done in 7 cases (14%) due to inadequate evacuation of the hematoma after TDC., Conclusion: Our modified technique of twist drill drainage is inexpensive, simple, safe and effective alternative technique in the treatment of CSDH.

The Jocic-Reeve and Corey-Link type reaction of dichloromethyllithium with suitably protected 5-keto-hexofuranoses followed by treatment with sodium azide and sodium borohydride reduction gave 5-azido-5-hydroxylmethyl substituted hexofuranoses 7a-c with required geminal dihydroxymethyl group. Removal of protecting groups and converting the C-1 anomeric carbon into free hemiacetal followed by intramolecular reductive aminocyclization with in situ generated C5-amino functionality afforded corresponding 5C-dihydroxymethyl piperidine iminosugars 2a-c. Alternatively, removal of protecting groups in 7b and 7c and chopping of C1-anomeric carbon gave C2-aldehyde that on intramolecular reductive aminocyclization with C5-amino gave 4C-dihydroxymethyl pyrrolidine iminosugars 1b and 1c, respectively. On the basis of the (1)H NMR studies, the conformations of 2a/2b were assigned as (4)C(1) and that of 2c as (1)C(4). The glycosidase inhibitory activities of all five iminosugars were studied with various glycosidase enzymes and compared with natural d-gluco-1-deoxynojirimycin (DNJ). All the five compounds were found to be potent inhibitors of rice α-glucosidase with K(i) and IC(50) values in the nanomolar concentration range. Iminosugars 2b and 1b were found to be more potent inhibitors than their parent iminosugar. These results were substantiated by in silico molecular docking studies.

Since 1986, 68% of the Listeria monocytogenes isolates from human cases of invasive listeriosis in Sweden are available for retrospective studies. The aim of the present study was to characterize 601 human invasive isolates of L. monocytogenes in Sweden from 1986 to 2007 by using serotyping and pulsed-field gel electrophoresis. Since 1996, serovar 4b was permanently reduced to the second or third most common serovar in human cases in Sweden. During the latter period, 2000-2007, only 13% belonged to serovar 4b and 71% to 1/2a. The dendrogram, based on pulsovars, reveals two clusters with different serovars. Cluster 1 exhibits serovars 4b and 1/2b, whereas cluster 2 consists of serovar 1/2a. Serovar 1/2a seems to be more heterogeneous than serovar 4b.