Small rodent communities and their associated damage to wheat-groundnut agriculture systems

Abstract Rodents can cause significant damage to wheat-groundnut crops in developing countries, as well as to stored produce and infrastructure, affecting food security and income of small-holder farmers. Wheat (Triticum aestivum) and groundnuts (Arachis hypogea) are important cash crops for local farmers in Pakistan. Field experiments were performed to assess the extent of rodent damage to wheat-groundnut crops throughout their growth stages (i.e, germination, flowering/peg formation and maturity) in the agro-ecological zones of Pothwar Plateau, Pakistan. We used a quadrat method to record the number of damaged crop plants. On the basis of the trapping data four rodent species were captured from wheat-groundnut cropping systems which were responsible for causing damage, i.e., lesser bandicoot rat (Bandicota bengalensis) was the main species, followed by the short-tailed mole rat (Nesokia indica), the Indian gerbil (Tatera indica) and the bush rat (Golunda ellioti). In both crops, the maximum damage was recorded at crop maturity (10.7 and 14.4%, respectively). The lowest reported damage to wheat and groundnuts was at the germination stage (3.5% and 6.0%, respectively). The lower damage reported at germination could be due to availability of non-crop vegetation at field borders that may be a potential factor influencing damage. Our findings clearly show the considerable amount of damage caused by rodents to wheat-groundnut at maturity across all the agro-ecological zones of Pothwar and indicated that the small mammal composition was more related to maturity stage/season of crops, when the availability of food and climatic condition were favorable and having security under crop shelter. More detailed studies are needed to fully understand the population and breeding ecology of the relevant rodent pest species in relation to damage patterns to optimize management beyond individual structural measures.

OS07.2.A Evaluation of Intraoperative Surgical Adjuncts and Resection of Glioblastoma (ELISAR GB): A UK and Ireland multicentre, prospective observational cohort study

Background

Despite operative and adjuvant therapies, glioblastoma remains incurable, with the extent of resection being one of few treatments that can improve survival. To improve resection, operative adjuncts are used, with neuronavigation and 5-aminolevulinic acid (5-ALA) recommended as a standard of care in those aimed for maximal safe resection. Despite the standards, meta-analysis concluded that the impact of 5-ALA on the extent of surgical resection is of low quality due to bias in reporting tumour location and additional image guidance used, factors impacting on extent of resection as well as short-term neurological outcomes being uncertain. Therefore we aimed to evaluate the availability and use of 5-ALA and other adjuncts and compare surgical outcomes of 5-ALA-guided versus non-5-ALA-guided resections.

Material and Methods

A multicenter prospective observational cohort study was conducted across 27 out of 31 available centres in the UK and Ireland from 6 January until 19 March 2020. Inclusion criteria included adults with first diagnosis, supratentorial glioblastoma undergoing resection. Primary outcomes included: i) the availability and use of surgical adjuncts and ii) complete resection of enhancing tissue (CRET). Secondary outcomes included adverse events, new onset of postoperative neurological deficit and post-operative neurological function. Descriptive and inferential statistics were used for analysis with a p-value <0.05 deemed significant.

Results

232 consecutive cases were identified. 142/232 cases were aimed for maximal safe resection subsequently divided into 5-ALA-guided (n=92) versus non-5-ALA-guided (n=50) resections. 5-ALA and neuronavigation were available across all centres. Neuronavigation and 5-ALA were used in 91% (n=129/142) and 65% (n=92/142) of cases aimed for maximal safe resection whereas 83% (n=75/90) and 49% (n=44/90) for debulk surgery. 35 unique combinations of surgical adjuncts were used in 232 operations. 5-ALA-guided resection yielded a higher percentage of CRET than without (55% versus 28%, p < 0.01). The two groups showed no difference in adverse events (p=0.98), new onset of neurological deficit (p=0.88) nor neurological function (p=0.7). A logistic regression analysis showed that 5-ALA was an important predictor of CRET regardless of additional adjuncts used (OR 2.4, CI 0.96-5.97, P = 0.05), tumour location and molecular characterisation (OR 3.48, CI 1.61-7.51, P <0.01).

Conclusion

Firstly, we showed that 5-ALA is not always used for glioblastoma aimed for CRET. Secondly, we report a great heterogeneity of adjuncts used for resection, possibly explained by a lack of high-quality evidence and surgeon training. Thirdly we demonstrate that 5-ALA-guided resection leads to higher percentage of CRET regardless of other adjuncts used, tumour location and molecular characterisation.

930 Cauda Equina Syndrome Referrals: A Single Centre Experience

Aim

Cauda Equina Syndrome (CES)is a neurosurgical emergency that requires prompt surgical intervention. History and examination performed by referring departments play an imperative role in the triaging of these patients for onward radiological investigation. We aimed to compare radiologically confirmed cauda equina syndrome to the CES referrals to our tertiary unit to elucidate the true regional incidence of CES.

Method

All CES referrals over a 4 year period (2018–2021) made using the electronic patient referral portal, referapatient.orgtm, were collated. The incidence of radiological confirmed CES was identified.

Results

2018: 231 CES referrals of which 26 were radiological CES and accepted (14 female and 12 male).

2019: 151 referrals of which 20 were radiological CES and accepted (14 female and 6 male).

2020: 257 referrals of which 28 were radiological CES accepted (16 female and 12 male).

2021 (first 6 months): 89 referrals of which 16 were radiological CES and accepted (7 female and 9 male).

Conclusions

In 2018–2021 we received 728 CES referrals of which 90 were radiologically CES and required surgical management. There were 51 female and 39 male patients.

211 referrals were from our own Hospital (Hub) while 517 referrals were from 6 other (Spoke) Hospitals. 12.36% had radiological CES.

This represents just over 1 in 10 referrals from secondary care facilities. A greater understanding of the condition via the utilisation of large electronic datasets may facilitate the formulation of novel scoring systems to more accurately appraise cases of putative CES to avoid unnecessary transfers to tertiary centres.

378 Endovascular Stenting vs. Open Surgery in Cerebral AVF Patients

Introduction

Intracranial dural arteriovenous fistulae (dAVF), typically found in the dural leaflets, are vascular malformations defined by a pathological communication between meningeal arteries and dural sinus or cortical veins. Despite many of them spontaneously resolving, they are still at high risk of hemorrhage and mortality if not effectively treated and monitored. Treatment options include endovascular embolization, surgical disconnection, and radiosurgery. With the rise of endovascular treatments now widely available, there is a massive shift towards minimally invasive surgical options while it can still be argued they are not the end of open surgical repairs.

Method

We reviewed 12 cases each of endovascular embolization and microsurgical resection in our Neurosurgical Unit retrospectively and compare between length of hospital stay, hemorrhage, need for open surgery following endovascular technique and wound infection. Cases will be selected at random over a period of 6 months.

Results

We compared surgical outcomes of 12 cases each of dural AvFs that were either managed as surgical repair or endovascular embolization. In cases with associated complication, surgical repair was the preferred method although endovascular repairs had shorter length of hospital stay, lower rates of infections and rarely needed to be followed by surgical repair.

Conclusions

Based on the result we conclude that endovascular repairs have a shorter length of hospital stay, infections and hemorrhage, yet there are instances where surgical disconnection may be the preferred treatment method on a case-by-case basis. Endovascular treatment may not have replaced open surgical procedures just yet, but the future may hold more advances in this field.

353 The Rise of the Exoscope

Introduction

An exoscope is a next generation HD telescope video monitoring system used to perform microsurgeries that is now a formidable rival to the existing operating microscope in neurosurgery. While the microscope revolutionised neurosurgery with its advent in 1957, the exoscope allows surgeons to operate utilising high-definition images enhancing the field of vision and focus. The exoscope opens new avenues with regards to ergonomics, teaching in theatre and enhances the surgeon’s experience.

Method

We will do a literature review on available literature on the use of exoscope in neurosurgery with regards to the operating microscope. Both qualitative and quantitative data will be reviewed. Personal experience of Neurosurgeons in our unit will also be reviewed using questionnaires.

Results

The exoscope has many benefits when compared to the operating microscope where it surpasses its predecessor in many ways. 15 studies were reviewed where the exoscope was compared to the operating microscope which concluded the exoscope equal or superior in many aspects such as teaching, ergonomics, image definition and being user friendly. There were some pitfalls of the exoscope reported such as the image being in 2D which limited the surgeon’s stereoscopic vision and the costs involved.

Conclusions

The exoscope is a revolutionary advent in neurosurgery and may soon make the operating microscope obsolete but there is still room for improvement.

343 Medical Teaching in the Covid Era: The Rise of the Webinar

Background

Since the emergence of COVID-19, virtually the whole world has been forced to into lockdown and adapt to a way of life not seen in living memory. Although pandemics are not new, nor will this likely be the last, the modern era has one major advantage that our ancestors did not have: the internet.

Through the usage of modern technology and the internet, we have been able to continue our professional lives through a virtual medium through programs like Zoom. As part of this virtual shift, medical teaching is also mainly online. A QI study was conducted on webinars.

Aim

To determine whether medical students and junior doctors find online teaching to be an effective medium of learning, as well as to determine the advantages and disadvantages, including mental health impact.

Method

A webinar series was created, entitled back2basics (B2B) surgery, which was run for around 2 months with weekly, 1-hour long webinars on a surgical topic. Feedback was collected following each session specific to that week’s webinar as a general opinion of our participants on webinars.

Results

Both qualitative and quantitative data was collected. The majority (83%) of participants agreed by the 8th week that webinars were an effective mode of medical teaching compared to 48% in the 1st week. Participants pointed out that webinars are ‘low pressure’ and ‘less competitive’ than in person lectures, so good for mental health.

Conclusions

Participants agree that the webinars are effective for medical teaching and that there are mental health benefits.

Dietary habits of lesser bandicoot rat (Bandicota Bengalensis) in an agro-ecosystem, Pothwar Plateau, Pakistan

Dietary habits of bandicoot rats (bandicota bengalensis) were investigated in the agricultural crops of the Pothwar Plateau, Pakistan by analysing stomach contents. The research activities were conducted in major field crops including wheat-groundnut and in the fallow lands during non-crop season at the field boundaries. The specimens were captured from the fields using kill/snap traps, and dissected to collect their stomach samples for laboratory analysis. Light microscopic slides of the plant material were recovered from stomach samples and the reference materials were collected from the field. Results revealed that the bandicoot rat predominantly fed upon cultivated crops during cropping season but consumed wild vegetation during non-cropping season. There was no significance difference between summer and winter diets. Most frequently consumed crop food items were wheat (Triticum aestivum; 28.57%), groundnut (Arachis hypogea; 11.26%), sorghum (Sorghum bicolor; 10.17%), chickpea (Cicer arietinum; 9.52%), maize (Zea mays; 6.49%), millet (Pennisetum glaucum; 5.84%), barley (Hordeum vulgare; 4.98%) and mustard (Brassica campestris; 4.98%). Among wild vegetation were consumed khbal gha (Cynodon dactylon; 7.79%), baron dhab (Demostachya bipinnata; 7.36%) and Prickly flower (Achyranthes aspera; 3.03%). The study concludes that, in addition to consuming wheat and groundnut crops, the Lesser bandicoot rat also subsists on grasses, weeds, and some fodder crops, as important component of its diet in agro-ecosystem of the Pothwar Plateau.

854 Mortality Associated with Conversion of Total Hip Arthroplasty for Failed Fixation/Hemiarthroplasty for Neck of Femur Fractures

Aim

To identify the mortality associated with failed internal fixation and hemiarthroplasty of neck of femur fractures.

Method

Patients undergoing conversion of internal fixation / hemi arthroplasty were identified from theatre records and surgical databases. Data was stored in Microsoft Excel spreadsheet. Clinical outcomes at 30 days, 1 year and 5 years post conversion total hip replacement.

Results

60 cases were collected between June 2006 and November 2016. 46 females and 14 males involved in the case. The mean age of male patients was 66.5 and for females 67.9. 32 patients had previous sliding hip screw fixation,12 had intra-medullary nails, 8 had cannulated screw fixation and 5 patients had hemiarthroplasty. The mean time to failure was 22 months (Range: 2 weeks to 60 months) and there were 6 cases of late posttraumatic arthritis (range 4 yrs to 23 yrs). Average time from documented failure to conversion THR was 2 months. There were 2 superficial wound infections which were successfully treated with antibiotics. There were 2 cases of deep infection which required multiple debridement, washout, and prolonged inpatient stay. Average duration of hospital stay was 5.7days. 18 patients died before 5 years for reasons unrelated to their hip. All had a functional prosthesis at time of last review. 42 patients alive at 5 years had a functional prosthesis at last review

Conclusions

Total Hip Arthroplasty is a successful procedure for failed fixation / hemiarthroplasty despite the technical challenges. A 3–5-year mortality rate of 33.33 % reflects well against the NHFD 1year mortality of 30 %.

Progression pattern and adverse events with bevacizumab in glioblastoma

BACKGROUND

The use of bevacizumab in the management of glioblastoma multiforme (gbm) remains controversial. In Canada, bevacizumab is approved for the treatment of recurrent gbm. We describe a pattern of progression across treatment lines in gbm.

METHODS

During 2008-2014, 64 patients diagnosed with gbm were treated with bevacizumab at McGill University hospitals. Of those patients, 30 (46.9%) received bevacizumab in the first line (B1L), and 34 (53.1%) received it in the second line and beyond (B2L+). The average length of treatment with bevacizumab was 24.4 weeks (range: 0-232.7 weeks). The patterns of progression were categorized as local, distant, diffuse, multifocal, or multi-pattern.

RESULTS

Local progression was seen in 46.7% of B1L patients and 26.5% of B2L+ patients, distant in 3.3% and 2.9%, diffuse in 20% and 47%, multifocal in 10% and 8.8%, and multi-pattern in 3.3% and 11.8%. No differences between the groups were observed for the distant (p = 0.3) or diffuse (p = 0.4) patterns. Grades 3 and 4 adverse events in the B1L and B2L+ groups were fatigue (33.3% vs. 17.6% respectively), hypertension (26.7% vs. 5.9%), thrombocytopenia (26.7% vs. 11.8%), neutropenia (26.7% vs. 11.8%), anemia (23.3% vs. 11.8%), leucopenia (20% vs. 8.8%), deep vein thrombosis (23.3% vs. 5.9%), seizure (16.7% vs. 8.8%), brain hemorrhage (6.7% vs. <1%), and delayed wound healing (6.7% vs. 2.9%). More total grades 3 and 4 adverse events occurred in the B1L group (p = 0.000519).

CONCLUSIONS

In our cohort, patterns of progression were not different in B1L and B2L+ patients. Moreover, both groups experienced similar adverse events, although more grades 3 and 4 events occurred in the B1L group, implying that severe adverse events in B1L patients could negatively affect survival outcomes.

Retrospective analysis of the effect of CAPOX and mFOLFOX6 dose intensity on survival in colorectal patients in the adjuvant setting

BACKGROUND

Despite lack of a true comparative study, the folfox (5-fluorouracil-leucovorin-oxaliplatin) and capox (capecitabine-oxaliplatin) regimens are believed to be similar in their efficacy and tolerability in the treatment of stage iii colorectal cancer. However, that belief has been disputed, because real-life data suggest that the capox regimen is more toxic, leading to more frequent reductions in the delivered dose intensity-thus raising questions about the effect of dose intensity on clinical outcomes.

METHODS

A retrospective data review for two Canadian institutions, the Segal Cancer Centre and the Tom Baker Cancer Centre, considered patients diagnosed with stage iii colorectal cancer during 2006-2013. Primary endpoints were dose intensity and toxicity, with a secondary endpoint of disease-free survival.

RESULTS

The study enrolled 180 eligible patients (80 at the Segal Cancer Centre, 100 at the Tom Baker Cancer Centre). Of those 180 patients, 75 received capox, and 105 received mfolfox6. In the capox group, a significant dose reduction was identified for capecitabine compared with 5-fluorouracil in mfolfox6 group (p = 0.0014). Similarly, a significant dose reduction was observed for oxaliplatin in mfolfox6 compared with oxaliplatin in capox (p = 0.0001). Compared with the patients receiving capox, those receiving mfolfox6 were twice as likely to experience a treatment delay of more than 1 cycle-length (p = 0.03855). Toxicity was more frequent in patients receiving mfolfox6 (nausea: 30% vs. 18%; diarrhea: 47% vs. 24%; peripheral sensory neuropathy: 32% vs. 3%). At a median follow-up of 40 months, preliminary data showed no difference in disease-free survival (p = 0.598). Pooled data from both institutions were also separately analyzed, and no significant differences were found.

CONCLUSIONS

Our results support the use of capox despite a lack of head-to-head randomized trial data.

Quantifying treatment delays in adolescents and young adults with cancer at McGill University

BACKGROUND

Since the end of the 1980s, the magnitude of survival prolongation or mortality reduction has not been the same for adolescents and young adults (ayas) with cancer as for their older and younger counterparts. Precise reasons for those observations are unknown, but the differences have been attributed in part to delays in diagnosis and treatment. In 2003 at the Jewish General Hospital, we developed the first Canadian multidisciplinary aya oncology clinic to better serve this unique patient population. The aim of the present study was to develop an approach to quantify diagnosis delays in our aya patients and to study survival in relation to the observed delay.

METHODS

In a retrospective chart review, we collected information about delays, treatment efficacy, and obstacles to treatment for patients seen at our aya clinic.

RESULTS

From symptom onset, median time to first health care contact was longer for girls and young women (62 days) than for boys and young men (6 days). Median time from symptom onset to treatment was 173 days; time from first health care contact to diagnosis was the largest contributor to that duration. Delays in diagnosis were shorter for patients who initially presented to the emergency room, but compared with patients whose first health contact was of another type, patients presenting to the emergency room were 3 times more likely to die from their disease.

CONCLUSIONS

Delays in diagnosis are frequently reported in ayas with cancer, but the duration of the delay was unrelated to survival in our sample. Application of this approach to larger prospective samples is warranted to better understand the relation between treatment delay and survival in ayas-and in other cancer patient groups.

Reversible brainstem dysfunction from spinal arterio-venous fistula

A 45-year-old man presented with subacute onset of ataxia, diplopia, urinary retention and paraparesis. MR scan of brain showed abnormal T2 hyperintense signal within the cervical cord, medulla and lower pons and vascular appearances suggesting an arterio-venous fistula. The fistula was surgically explored and successfully disconnected with good clinical outcome. Brainstem or cervical dural arterio-venous fistulae more typically present as a myelopathy; only a handful of cases have presented with brainstem dysfunction. This is a rare but reversible cause of subacute brainstem dysfunction.

EPR properties of synthetic apatites, deorganified dentine, and enamel

Electron paramagnetic resonance spectroscopy (EPR) was used to study synthetic hydroxyapatite and approximately 1, 2, and 6% synthetic carbonated apatites, deorganified dentine, and enamel. The carbonated apatites were synthesized by hydrolysis of dicalcium phosphate. Comparisons were made with spectra from enamel and deorganified dentine. Microwave power saturation and dose responses were determined for the synthetic materials. The Marquardt version of the Levenberg decomposition method was used to extract individual signals from the apatite data. Two samples of dentine were irradiated with 25 and 100 Gy, respectively, from a 60Co source. The first sample was then deorganified at 200 degreesC using the Soxhlet extraction technique. A third sample was irradiated with 100 Gy after deorganification. The resulting EPR spectra were then compared. It was determined that the dosimetric signal of 2% synthetic carbonated apatite was approximately the same as that of enamel. It was also verified that the dosimetric signal saturates at about 2% in synthetic carbonated apatites. The study established that the precenters responsible for the dosimetric signal (g perpendicular = 2.0018, g parallel = 1.9985) are preferentially concentrated in the surface-accessible region of the mineral component, as shown by the approximately 80% attenuation of the dosimetric signal in dentine following deorganification. The precenters responsible are not destroyed by the deorganification since the magnitude of the dosimetric signal from the dentine specimen irradiated following deorganification was approximately twice that of the comparable untreated, irradiated sample. Finally, the dose response of 2 and 6% synthetic carbonated apatites was determined.

Ergonomic design of a barber's workstation

Long hours of work while standing have been known to cause health problems for humans. Such professions include that of the barber. A survey was conducted of barbers from different barber shops in Saudi Arabia to determine their discomfort level. A prototype workstation was then designed and constructed in which the barber sits and performs work. The workstation was tested by nine barbers in the Human Factors Laboratory in the Systems Engineering Department at King Fahd University of Petroleum and Minerals. These barbers were among those surveyed earlier in their shops. Their discomfort level was again taken and an experiment was conducted to design the shape of the footrest. The discomfort levels obtained while standing and sitting were statistically analysed. From the results, it was concluded that the mean of the discomfort levels while standing is significantly (alpha = 0.01) higher than that while sitting.

The Drosophila dCREB-A gene is required for dorsal/ventral patterning of the larval cuticle

We report on the characterization of the first loss-of-function mutation in a Drosophila CREB gene, dCREB-A. In the epidermis, dCREB-A is required for patterning cuticular structures on both dorsal and ventral surfaces since dCREB-A mutant larvae have only lateral structures around the entire circumference of each segment. Based on results from epistasis tests with known dorsal/ventral patterning genes, we propose that dCREB-A encodes a transcription factor that functions near the end of both the DPP- and SPI-signaling cascades to translate the corresponding extracellular signals into changes in gene expression. The lateralizing phenotype of dCREB-A mutants reveals a much broader function for CREB proteins than previously thought.

The joy of doctoring

What makes doctoring joyful? Important issues may involve the organization and management of the practice setting; the physician needs to focus on the human aspects of doctoring as well.

Safety, infectivity, transmissibility and immunogenicity of rhesus rotavirus vaccine (MMU 18006) in infants

In an attempt to evaluate the immunogenicity, infectivity, transmissibility and safety of rhesus rotavirus vaccine (RRV) MMU 18006, 27 infants ages 5 to 20 months participated in two randomized, double-blind placebo controlled trials, one in a day care setting to allow for child to child contact and close surveillance and the other on an outpatient basis. Fourteen infants (mean age, 8.3 months) received 10(5) plaque-forming units of RRV and 13 (mean age, 11.1 months) received placebo. In the eight infants who participated in the vaccine trial in the day care setting, there was no evidence of transmissibility of RRV, by either stool excretion or seroconversion. The data from both trials showed RRV to be 100% infective and immunogenic in the vaccinees. There were no gastrointestinal side effects although there was an association between vaccine administration and fever occurring on Days 3 and 4. Based on these encouraging preliminary results, further work is proceeding to evaluate this vaccine at lower doses in this age group of infants.