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Plant resistance to the feeding by herbivorous insects has recently been found to be positively or negatively influenced by prior egg deposition. Here we show how crucial it is to conduct experiments on plant responses to herbivory under conditions that simulate natural insect behaviour. We used a well-studied plant--herbivore system, Arabidopsis thaliana and the cabbage white butterfly Pieris brassicae, testing the effects of naturally laid eggs (rather than egg extracts) and allowing larvae to feed gregariously as they do naturally (rather than placing single larvae on plants). Under natural conditions, newly hatched larvae start feeding on their egg shells before they consume leaf tissue, but access to egg shells had no effect on subsequent larval performance in our experiments. However, young larvae feeding gregariously on leaves previously laden with eggs caused less feeding damage, gained less weight during the first 2 days, and suffered twice as high a mortality until pupation compared to larvae feeding on plants that had never had eggs. The concentration of the major anti-herbivore defences of A. thaliana, the glucosinolates, was not significantly increased by oviposition, but the amount of the most abundant member of this class, 4-methylsulfinylbutyl glucosinolate was 1.8-fold lower in larval-damaged leaves with prior egg deposition compared to damaged leaves that had never had eggs. There were also few significant changes in the transcript levels of glucosinolate metabolic genes, except that egg deposition suppressed the feeding-induced up-regulation of FMOGS-OX2 , a gene encoding a flavin monooxygenase involved in the last step of 4-methylsulfinylbutyl glucosinolate biosynthesis. Hence, our study demonstrates that oviposition does increase A. thaliana resistance to feeding by subsequently hatching larvae, but this cannot be attributed simply to changes in glucosinolate content.

Coat color dilution turns black coat color to blue and red color to cream and is a characteristic in many mammalian species. Matings among Netherland Dwarf, Loh, and Lionhead Dwarf rabbits over two generations gave evidence for a monogenic autosomal recessive inheritance of coat colour dilution. Histological analyses showed non-uniformly distributed, large, agglomerating melanin granules in the hair bulbs of coat color diluted rabbits. We sequenced the cDNA of MLPH in two dilute and one black rabbit for polymorphism detection. In both color diluted rabbits, skipping of exons 3 and 4 was present resulting in altered amino acids at p.QGL[37-39]QWA and a premature stop codon at p.K40*. Sequencing of genomic DNA revealed a c.111-5C>A splice acceptor mutation within the polypyrimidine tract of intron 2 within MLPH. This mutation presumably causes skipping of exons 3 and 4. In 14/15 dilute rabbits, the c.111-5C>A mutation was homozygous and in a further dilute rabbit, heterozygous and in combination with a homozygous frame shift mutation within exon 6 (c.585delG). In conclusion, our results demonstrated a colour dilution associated MLPH splice variant causing a strongly truncated protein (p.Q37QfsX4). An involvement of further MLPH-associated mutations needs further investigations.

Forecasting the consequences of accelerating rates of changes in biodiversity for ecosystem functioning requires a mechanistic understanding of the relationships between the structure of biological communities and variation in plant functional characteristics. So far, experimental data of how plant species diversity influences the investment of individual plants in direct chemical defences against herbivores and pathogens is lacking.We used Plantago lanceolata as a model species in experimental grasslands differing in species richness and composition (Jena Experiment) to investigate foliar concentrations of the iridoid glycosides (IG), catalpol and its biosynthetic precursor aucubin. Total IG and aucubin concentrations decreased, while catalpol concentrations increased with increasing plant diversity in terms of species or functional group richness. Negative plant diversity effects on total IG and aucubin concentrations correlated with increasing specific leaf area of P. lanceolata, suggesting that greater allocation to light acquisition reduced the investment into these carbon-based defence components. In contrast, increasing leaf nitrogen concentrations best explained increasing concentrations of the biosynthetically more advanced IG, catalpol. Observed levels of leaf damage explained a significant proportion of variation in total IG and aucubin concentrations, but did not account for variance in catalpol concentrations.Our results clearly show that plants growing in communities of varying species richness and composition differ in their defensive chemistry, which may modulate plant susceptibility to enemy attack and consequently their interactions with higher trophic level organisms.

Purpose: Postoperative fever is a common problem following neurosurgery but data on the causes among paediatric patients is sparse. In this report, we determined the incidence, causes, and outcomes of postoperative fever in paediatric neurosurgical patients (< 18 years), and contrasted the findings with an adult cohort published recently from our unit., Methods: We recruited 61 patients who underwent 73 surgeries for non-traumatic neurosurgical indications over 12 months. A standard protocol was followed for the evaluation and management of postoperative fever. We prospectively collected data pertaining to operative details, daily maximal temperature, clinical features, and use of surgical drains, urinary catheters, and other adjuncts. Elevated body temperature of > 99.9 °F or 37.7 °C for > 48 h or associated with clinical deterioration or localising features was considered as "fever"; elevated temperature not meeting these criteria was classified as transient elevation in temperature (TET)., Results: Twenty-six patients (35.6%) had postoperative fever, more frequent than in adult patients. TET occurred in 12 patients (16.4%). The most common causes of fever were aseptic meningitis (34.6%), followed by urinary tract infections (15.4%), pyogenic meningitis, COVID-19, and wound infections. Postoperative fever was associated with significantly longer duration of hospital admission and was the commonest cause of readmission., Conclusion: In contrast to adults, early temperature elevations in paediatric patients may portend infectious and serious non-infectious causes of fever, including delayed presentation with aseptic meningitis, a novel association among paediatric patients. Investigation guided by clinical assessment and conservative antibiotic policy in keeping with the institutional microbiological profile provides the most appropriate strategy in managing paediatric postoperative fever., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: During the ongoing COVID-19 pandemic, endonasal surgeries for sellar-suprasellar lesions were discouraged due to the risk of transmission of the disease. We reviewed the changes in our management protocol for these lesions as our disease understanding and preparedness evolved., Materials and Methods: This was a retrospective observational study including patients with sellar-suprasellar and clival lesions presenting to us between March and October 2020. Management protocols were divided into three phases based on the prevalence of the disease and the number of mandatory preoperative COVID-19 tests being conducted. The surgical approach used was analyzed in relation to the preferred approach during pre-COVID times, and surgical outcomes and complications were noted., Results: A total of 31 cases were operated during this period. During Phase I (low prevalence; no preoperative COVID testing) endonasal surgeries were largely abandoned in favor of transcranial approaches. In Phase II (medium prevalence; one preoperative COVID test) we gradually resumed endonasal surgeries for 'emergent' and 'essential' cases, and subsequently in Phase III (high prevalence; two preoperative COVID tests), we had no hesitation in performing 'elective' endonasal surgeries with additional barriers for prevention of aerosol transmission. No patient developed COVID-19 infection postoperatively. Eight HCWs in our department acquired the disease during this period, none of whom were directly involved in the surgeries for the above cohort of patients., Conclusions: With a strict preoperative COVID testing protocol, adherence to proper drilling techniques and using additional barriers to prevent droplet and aerosol spread, endonasal surgeries for sellar-suprasellar lesions are safe during this COVID-19 pandemic.

Objective: To analyze the outcomes of hypofractionated stereotactic radiotherapy (HFSRT) for Spetzler Martin grades 4 and 5 arteriovenous malformations (AVMs) in a pediatric population., Methods: Fourteen patients with Spetzler Martin (SM) grades IV and V large AVMs who underwent HFSRT between January 2013 and July 2019 were retrospectively reviewed. All patients received HFSRT at a dose of 30-36 Gy in 5 to 6 fractions. They were followed up annually with clinical and imaging assessments to evaluate obliteration rates., Results: The median age at presentation was 15 years (range 8-21 years). Ten (71%) were SM grade 4 AVMs and the rest were SM grade 5 AVMs. The majority presented with headache (8 [57%]), and 3 (21%) presented with bleeding. The median nidus volume was 39.4 cc (IQR, 31.4-52.4). Two (14%) patients had infratentorial AVMs. All of them had deep venous drainage. The median clinical follow-up duration was 75 months (range 31-107 months). There was complete obliteration of the nidus in 3 (21%) patients with a median time to obliteration of 39 months. HFSRT resulted in a reduction of the AVM volume to 12 cc or less in nearly 70% of patients. None of the patients experienced re-bleeding. 79% reported an improvement in their symptoms., Conclusion: HFSRT is a highly effective treatment for high-grade AVMs in children, which can result in either complete elimination or significant reduction of the nidus volume or make it suitable for additional treatment, such as single-session stereotactic radiosurgery (SRS)., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: We studied the clinico-radiological features and treatment outcomes of patients with aggressive spinal haemangiomas., Methods: We undertook a retrospective review of 24 patients with aggressive spinal haemangiomas managed at our centre from 2004 to 2016. The cohort was divided into two groups. Group1 included patients managed from 2004 to 2009 while Group 2 was those treated between 2010 and 2016. Clinicoradiological features and treatment outcomes were studied., Results: Back pain (24/24) and myelopathy (18/24) were the most common presenting complaints. Over 80% (20/24) of patients, had involvement of the thoracic spine and more than 50% (13/24) had severe spasticity, being Nurick grade 4&5 at presentation. The various treatment modalities used were laminectomy with or without instrumented posterior fusion (10/24), corpectomy with instrumented fusion (10/24) and alcohol injection alone (4/24). Patients who were treated with surgery had significant clinical improvement at follow-up in both groups. Patients who underwent alcohol injection did not have any improvement in symptoms at follow-up. There was a change in our strategy in the later part of the series from a two staged anterior and posterior approach to a single staged posterior-only approach to address vertebral body disease with preoperative angioembolization., Conclusion: Haemangiomas are benign lesions with locally aggressive behavior in some cases. Results of conservative approaches such as alcohol injection in management of these lesions are discouraging. Aggressive surgical decompression combined with preoperative adjuncts such as angioembolization with or without stabilization reduces intra operative blood loss and results in good neurological recovery even in patients with severe myelopathy., Competing Interests: All authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers; bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript., (© 2023 The Authors.)

While some volume of pneumocephalus occurs following any surgery entailing dural breach, tension pneumocephalus (TP) is a rare complication of endoscopic endonasal surgery described in less than 1% cases including expanded endoscopic endonasal approaches (EEEA). It is a neurosurgical emergency warranting urgent decompression. Two cases, who developed TP following EEEA are presented. One had sinonasal malignancy (adenoid cystic carcinoma) eroding the anterior skull-base (T4N0M0) and the other was a large olfactory groove meningioma. TP was heralded in both by sudden deterioration in neurological status. Both cases underwent bifrontal craniotomy for decompression with simultaneous skull-base repair incorporating a vascularised pericranial flap. Brief literature review regarding the pathophysiology, contributing factors, diagnosis, management, and prevention of TP following EEEA is presented. TP, a life-threatening neurosurgical emergency, warrants meticulous precautions for its prevention, and vigilant postoperative monitoring for early detection. Urgent decompression with thorough skull-base repair is imperative to prevent complications., Competing Interests: Conflict of interestAll authors declare they have no potential conflict of interest (financial and non-financial)., (© Association of Otolaryngologists of India 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Introduction: Nasal dermoid sinus cyst (NDSC) are uncommon congenital lesions in children., Objective: To review the clinical and radiological presentation and study the surgical outcomes of this uncommon lesion., Method: Retrospective chart review of all children diagnosed with nasal dermoid from 2010 to 2020 at a tertiary referral hospital in South India was executed. The medical records were reviewed for demographics, lesion characteristics, imaging, operative details, and outcomes and literature review was performed., Result: A total of 25 children [Mean age 3.7 yrs (Range 2-9 yrs)] with nasal dermoid sinus cysts were treated in the last decade. While 13 presented with a sinus, 11 presented with cyst and 1 had both. The lesions mainly involved the upper third of the nose in 10 children, middle one third in 6 and upper one third in 9 children. All underwent Magnetic Resonance Imaging, in 11 Computed Tomography also was done. A flow chart of the lesion characteristics and its management has been presented. Intraoperatively intracranial extension was present in four children. The approach to intracranial extension and corresponding literature review has been presented. Follow up ranged from one to six years. (Median 3.5 yrs) and no recurrence or complication was noted., Conclusion: Nasal dermoid is an uncommon congenital anomaly. Preoperative evaluation must include imaging to assess extent and rule out intracranial extension. Surgical strategy depends on whether presentation is as sinus or cyst and location and extent of lesion. All surgical approaches have a good surgical and cosmetic outcome., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Introduction: Synovial sarcoma is a rare mesenchymal malignant neoplasm that accounts for less than 10% of soft tissue sarcomas. About 95% of the sarcomas occur in the extremities. Primary synovial sarcomas of the spine are a rare tumor arising from the paravertebral regions, paraspinal muscles or epidural spaces. Purpose: To report an atypical radiological presentation of synovial sarcoma of the thoracic spine mimicking a nerve sheath tumor in an elderly adult and describe the management with review of the literature. Clinical presentation: A forty-six-year-old lady presented with clinical features of a thoracic intradural extramedullary cord compression at T7 level. She was Nurick grade 4 at presentation. MRI of the Thoracic spine with whole spine screening showed a contrast enhancing intradural extramedullary tumor at the T7-8 level; the tumor was exiting out through the left T7-8 neural foramina with foraminal widening. The possibility of a schwannoma was considered. Intervention: She underwent a T7-8 laminectomy and total excision of the tumor followed by posterior fusion. The biopsy was reported as synovial sarcoma. She subsequently underwent radiation and chemotherapy. She had marked improvement in her Neurological status and remained disease free at six months follow-up. Conclusion: Synovial sarcoma of the spine is a rare mesenchymal malignant neoplasm. One needs to consider Synovial sarcoma as one of the differential diagnosis of intradural tumors of the spine.

Objective: To determine whether preoperative non-lateralizing scalp electroencephalography (EEG) influences seizure outcome following peri-insular hemispherotomy (PIH) in pediatric hemispheric epilepsy., Methods: Retrospective data was collected on all 45 pediatric patients who underwent PIH between 2005 and 2016. All underwent a basic pre-surgical evaluation consisting of detailed history and examination, neuropsychological assessment, MRI, and EEG. SPECT/PET, fRMI, or Wada testing were done in only eight patients. Seizure outcome was assessed using the Engel classification., Results: Among those who underwent hemispherotomy, 20 (44%) were females. Mean age at surgery was 8 ± 4.3 years and mean duration of symptoms was 5.2 ± 3.7 years. The most common etiologies of hemispheric epilepsy were hemiconvulsion-hemiplegia epilepsy syndrome, Rasmussen encephalitis, and post-encephalitic sequelae, together comprising 27 (60%) patients. Among the 44 patients with follow-up data (mean duration 48 ± 33 months), seizure freedom (Engel class I) was attained by 41 (93.2%). Anti-epileptic medications were stopped or decreased in 36 (82%). Seventeen (38.6%) patients had non-lateralizing EEG. Seizure outcome was not related to lateralization of EEG activity., Conclusions: PIH provides excellent long-term seizure control in patients despite the presence of non-lateralizing epileptiform activity, although occurrence of acute postoperative seizures may be higher. Routine SPECT/PET may not be required in patients with a non-lateralizing EEG if there is good clinico-radiological concordance.

Competing Interests: There are no conflicts of interest

Colloid cysts are the most common benign neoplasms of the anterior third ventricle, mostly located at the level of the foramen of Monro and can often manifest as sudden onset headache or loss of consciousness. These cysts often have a well-defined cyst wall, mucinous or watery intracystic fluid and have a fairly good plane with the surrounding parenchyma. Occasionally, intracystic haemorrhage can lead to xanthogranulomatous inflammatory changes within the cyst resulting in focal thickening of the cyst wall and adhesion to the surrounding structures. Here we describe a case of xanthogranulomatous colloid cyst which is a very rare variant of colloid cyst.

Background: Intraoperative cerebrospinal fluid (CSF) leaks are a frequent cause of morbidity in patients undergoing transsphenoidal surgery. This prospective study was performed to examine the impact of intraoperative lumbar subarachnoid drainage (LSAD) on the incidence of this complication and on the extent of resection in patients undergoing endoscopic transsphenoidal surgery for pituitary adenomas., Materials and Methods: This prospective study was conducted in a single large academic medical center. All patients with pituitary adenomas who had not undergone prior transsphenoidal surgery were eligible for inclusion in the study. Patients were randomly assigned to undergo transsphenoidal surgery with intraoperative lumbar drain insertion (LSAD group) or no lumbar drain insertion (no LSAD group). An otolaryngologist independently determined the occurrence of an intraoperative CSF leak. Extent of tumor resection was determined by volumetric analysis of postoperative magnetic resonance images in patients with nonfunctional tumors or functional adenomas with a large suprasellar component., Results: Sixty patients were eligible for inclusion, of which 30 were assigned to the LSAD group and 30 to the no LSAD group. There were no statistically significant differences in patient demographics, tumor pathology, or radiology between the two groups. The LSAD catheter was successfully inserted in all patients in the LSAD group. Intraoperative CSF drainage significantly reduced the incidence of CSF leak from 46.7% in the no LSAD group to 3.3% in the LSAD group (P < 0.001). However, there were no statistically significant differences in the incidence of postoperative CSF rhinorrhea between the two groups. There were no major catheter-related complications. There was no statistically significant difference in the extent of resection between the two groups., Conclusions: Controlled intraoperative CSF drainage significantly reduces the incidence of intraoperative CSF leakage in patients undergoing endoscopic transsphenoidal surgery for pituitary adenomas.