A small proton charge radius from an electron-proton scattering experiment.

Elastic electron-proton scattering (e-p) and the spectroscopy of hydrogen atoms are the two methods traditionally used to determine the proton charge radius, rp. In 2010, a new method using muonic hydrogen atoms1 found a substantial discrepancy compared with previous results2, which became known as the 'proton radius puzzle'. Despite experimental and theoretical efforts, the puzzle remains unresolved. In fact, there is a discrepancy between the two most recent spectroscopic measurements conducted on ordinary hydrogen3,4. Here we report on the proton charge radius experiment at Jefferson Laboratory (PRad), a high-precision e-p experiment that was established after the discrepancy was identified. We used a magnetic-spectrometer-free method along with a windowless hydrogen gas target, which overcame several limitations of previous e-p experiments and enabled measurements at very small forward-scattering angles. Our result, rp = 0.831 ± 0.007stat ± 0.012syst femtometres, is smaller than the most recent high-precision e-p measurement5 and 2.7 standard deviations smaller than the average of all e-p experimental results6. The smaller rp we have now measured supports the value found by two previous muonic hydrogen experiments1,7. In addition, our finding agrees with the revised value (announced in 2019) for the Rydberg constant8-one of the most accurately evaluated fundamental constants in physics.

First Report of Barley yellow striate mosaic virus on Wheat in China.

In the spring of 2014, a survey of viral diseases on wheat (Triticum aestivum L.) was carried out in Hebei Province, China. The samples with virus-like symptoms of dwarfing and flag leaf yellowing were collected in Zhaoxian, Quyang, Anxin, and Luannan. To reproduce the viral symptoms and confirm whether the unknown virus was transmitted by insect vectors, the nymphs of aviruliferous planthopper (Laodelphax striatellus Fallen, Homoptera: Delphacidae) were transferred onto diseased wheat from the field for a 3-day acquisition access period and a 10-day incubation on fresh wheat seedlings, and then were exposed to 2- to 3-leaf stage wheat seedlings of wheat variety Shixin828 for a 3-day inoculation access period. The infected wheat plants developed mosaic symptoms on the young leaves at 7 days post inoculation (dpi), and followed with severe symptoms including stunting, chlorotic spots, and striation along the veins of leaves at around 14 dpi. The infection symptoms were same as in the field but distinct from wheat infected with Rice black streaked dwarf virus (RBSDV) or Northern cereal mosaic virus (NCMV). For further confirmation, total RNA was extracted from the symptomatic wheat leaves, and NCMV specific primers, NCMV-PF/NCMV-PR (5'-ATGGATAAGAAAGCAAGTGGA-3'/5'-TTAAAAGTCGGCATACGGGTC-3') and RBSDV specific primers, S10-F/S10-R (5'-TTACCCAACATCACGCAACT-3'/5'-GAGCAGGAACTTCACGACAAC-3') were used for amplification of sequences of phosphoprotein and coat protein genes, respectively. Neither RBSDV nor NCMV were present in the symptomatic tissue according to the RT-PCR assay (4). Tissues derived from symptomatic wheat leaves were fixed and embedded in Spurr's resin and used for ultra-thin sectioning and transmission electron microscopy observations, revealing large amounts of Rhabdovirus-like particles in the cytoplasm. The identified particles were about 315 to 353 × 46 to 57 nm, similar in size to Barley yellow striate mosaic virus (BYSMV), a member of the genus Cytorhabdovirus reported from Italy (2). The specific primer pair (5'-ACTAAGGGGGTACTCCGACC-3' and 5'-CTGATCTGCTTTGAGGGGCA-3') was designed based on the reported polymerase (L) gene sequence of BYSMV isolate Zanjan-1 (GenBank Accession No. FJ665628) (1), and used for the BYSMV detection by RT-PCR. A single bright band of the expected size (~500 bp) was obtained from total RNA extracted from the plants exhibiting symptoms in the greenhouse. No such band was amplified from asymptomatic plants, while 15 out of 23 field samples also produced the same 500-bp products in RT-PCR. PCR products from three virus-positive field samples were sequenced directly and the sequences were submitted to GenBank (KM052176, KM052177, and KM052178). BLAST search showed that the sequences shared 96 to 97% nucleotide identity with the polymerase L gene sequence of BYSMV isolate Zanjan-1, whereas only 73 to 75% identity with NCMV (AB030277 and GU985153) (1,3,5). To our knowledge, this is the first report of BYSMV occurrence on wheat in China. References: (1) R. Almasi et al. J. Phytopathol. 158:351, 2010. (2) A. Appiano et al. Cytol. 6:105, 1974. (3) H. C. Chen et al. Sci. Agric. Sinica 3:64, 1980. (4) X. F. Duan et al. Acta Phytopathol. Sinica 40:337, 2010. (5) F. Tanno et al. Arch. Virol. 145:1373, 2000.

Exploring the feasibility of pupillometry training and perceptions of potential use for intracranial pressure monitoring in Uganda: A mixed methods study.

INTRODUCTION: Traumatic brain injury (TBI) accounts for the majority of Uganda's neurosurgical disease burden; however, invasive intracranial pressure (ICP) monitoring is infrequently used. Noninvasive monitoring could change the care of patients in such a setting through quick detection of elevated ICP. PURPOSE: Given the novelty of pupillometry in Uganda, this mixed methods study assessed the feasibility of pupillometry for noninvasive ICP monitoring for patients with TBI. METHODS: Twenty-two healthcare workers in Kampala, Uganda received education on pupillometry, practiced using the device on healthy volunteers, and completed interviews discussing pupillometry and its implementation. Interviews were assessed with qualitative analysis, while quantitative analysis evaluated learning time, measurement time, and accuracy of measurements by participants compared to a trainer's measurements. RESULTS: Most participants (79%) reported a positive perception of pupillometry. Participants described the value of pupillometry in the care of patients during examination, monitoring, and intervention delivery. Commonly discussed concerns included pupillometry's cost, understanding, and maintenance needs. Perceived implementation challenges included device availability and contraindications for use. Participants suggested offering continued education and engaging hospital leadership as implementation strategies. During training, the average learning time was 13.5 minutes (IQR 3.5), and the measurement time was 50.6 seconds (IQR 11.8). Paired t-tests to evaluate accuracy showed no statistically significant difference in comparison measurements. CONCLUSION: Pupillometry was considered acceptable for noninvasive ICP monitoring of patients with TBI, and pupillometer use was shown to be feasible during training. However, key concerns would need to be addressed during implementation to aid device utilization.

The feasibility, appropriateness, and usability of mobile neuro clinics in addressing the neurosurgical and neurological demand in Uganda.

INTRODUCTION: Uganda has a high demand for neurosurgical and neurological care. 78% of the over 50 million population reside in rural and remote communities where access to neurosurgical and neurological services is lacking. This study aimed to determine the feasibility, appropriateness, and usability of mobile neuro clinics (MNCs) in providing neurological care to rural and remote Ugandan populations. METHODS: Neurosurgery, neurology, and mobile health clinic providers participated in an education and interview session to assess the feasibility, appropriateness, and usability of the MNC intervention. A qualitative analysis of the interview responses using the constructs in the updated Consolidated Framework for Implementation Research was performed. Providers' opinions were weighted using average sentiment scores on a novel sentiment-weighted scale adapted from the CFIR. A stakeholder analysis was also performed to assess the power and interest of the actors described by the participants. RESULTS: Twenty-one healthcare providers completed the study. Participants discussed the potential benefits and concerns of MNCs as well as potential barriers and critical incidents that could jeopardize the intervention. Of the five CFIR domains evaluated, variables in the implementation process domain showed the highest average sentiment scores, followed by the implementation climate constructs, inner setting, innovation, and outer setting domains. Furthermore, many interested stakeholders were identified with diverse roles and responsibilities for implementing MNCs. These findings demonstrate that MNC innovation is feasible, appropriate, and usable. CONCLUSION: The findings of this study support the feasibility, appropriateness, and usability of MNCs in Uganda. However, integration of this innovation requires careful planning and stakeholder engagement at all levels to ensure the best possible outcomes.

A Mixed-Methods Assessment of the Feasibility of Conducting Neurosurgical Clinical Research in Uganda.

BACKGROUND: Clinical research is necessary to evaluate neurosurgical interventions, yet clinical trials are conducted less frequently in low- and middle-income countries. Because specific barriers, facilitating factors, and strategies for neurosurgical clinical research in Uganda have not been previously identified, this study evaluated neurosurgical providers' perspectives on clinical research and documentation patterns of neurosurgical variables at Mulago National Referral Hospital. METHODS: Retrospective review of 166 neurosurgical patient charts assessed the frequency of documentation of key variables. Twenty-two providers working in neurosurgery participated in 6 focus group discussions with qualitative analysis utilizing the framework method. RESULTS: Chart review showed that primary diagnosis (99.4%), pupil light response (97.6%), and computed tomography scan results (93.3%) were documented for most patients. Cranial nerve exam (61.5%), pupil size (69.9%), and time to neurosurgical intervention (45%) were documented less frequently. On average, Glasgow Coma Scale was documented for 86.6% of days hospitalized, while vital signs were documented for 12.3%. In most focus group discussions, participants identified follow-up, financing, recruitment, time, approval, and sociocultural factors as research barriers. Participants described how the current health workforce facilitates successful research. To improve research capacity, suggested strategies focused on research networks, data collection, leadership, participant recruitment, infrastructure, and implementation. CONCLUSIONS: At Mulago National Referral Hospital, there was variability in the frequency of documentation of neurosurgical variables, which may impact data collection for future studies. While multiple barriers were identified, sociocultural, financing, and time barriers greatly impacted neurosurgical clinical research. Despite that, identified facilitating factors and strategies could be utilized to support neurosurgical research capacity growth.

The Epidemiology of Spinal Neurosurgery in Nigeria: A Systematic Review and Patient-Level Analysis.

OBJECTIVE: Spinal pathologies are prevalent in Nigeria, though epidemiological data remains sparse. This systematic review used pooled patient-level data from across the country to generate a standardized epidemiological reference. METHODS: Four research databases and gray literature sources were searched. Risk of bias assessment was conducted using Risk of Bias in Non-Randomised Studies - of Interventions and Cochrane's risk of bias tool. We descriptively analyzed all article metrics and statistically analyzed relevant data variables via paired t-test and χ2 independence tests (α = 0.05). RESULTS: One hundred twenty-seven articles, comprising a patient cohort of 8425 patients, were analyzed. Most were retrospective cohort studies (46.5%) and case reports/series (31.5%), with an overall moderate-high risk of bias. Most studies were published in the last 20 years. Most patients were male (∼2.5 males per female), with an average age of 43.2 years (±16.4). Clinical diagnoses spanned the breadth of spinal neurosurgery. Approximately 45.0% of patients had complete spinal impairment. Pain (41.7%) was the most reported presenting feature. X-ray (45.1%) was the most common investigation used. Intervertebral disc herniation (18.9%) was the most prevalent imaging finding on MRI. Most patients were managed nonoperatively (57.8%), with a favorable outcome in 27.4% of patients. Posttreatment complications included pressure sores, infection, and motor deficits. CONCLUSIONS: This systematic review and pooled analysis provide an epidemiological overview of spinal neurosurgery in Nigeria over the last 60 years and serves as a useful reference to direct future global research in this arena.

The Epidemiological Burden of Neurovascular Pathology in Nigeria: A Systematic Review and Pooled Patient-Level Analysis.

OBJECTIVE: Vascular neurosurgery has developed significantly in Nigeria, but its burden and challenges remain unclear. This study systematically reviewed vascular neurosurgical literature from Nigeria. METHODS: Four research databases and gray literature sources were searched from 1962-2021. ROBINS-I tool was used to assess risk of bias. Descriptive, narrative, and statistical analyses were conducted on all variables. Where appropriate, paired t-tests and Chi-squared independence tests were used (α = 0.05). RESULTS: 56 articles were included and 3203 patients pooled for analysis. Risk of bias was moderate-high. Most articles were published over the last 20 years with retrospective cohort studies and case reports being the most common study designs. The cohort had a relatively even gender split and an average age of 49 years (±22). Cerebrovascular accidents accounted for over 85% of diagnoses, with most etiologies being traumatic. Headache and motor deficit were the most prevalent clinical features. X-ray and carotid angiography were the most commonly reported imaging modalities, closely followed by computed tomography (CT) and CT angiography. The top two radiological diagnoses were ischemic cerebrovascular disease and intracerebral hematoma. Aneurysmal clipping and hematoma evacuation were the most commonly reported treatment modalities. Outcome at last follow-up was favorable in 48%. The mortality rate was 6%. Post-treatment complications included chest infection and rebleeding. CONCLUSIONS: This study illustrates the epidemiological burden of neurovascular pathology (based on the available data in published literature) in Nigeria, and raises awareness amongst service providers and researchers of the attendant challenges and epochal trends seen within vascular neurosurgery in Nigeria.

Epidemiological Burden of Neurotrauma in Nigeria: A Systematic Review and Pooled Analysis of 45,763 Patients.

OBJECTIVE: Neurotrauma is a significant cause of morbidity and mortality in Nigeria. We conducted this systematic review to generate nationally generalizable reference data for the country. METHODS: Four research databases and gray literature sources were electronically searched. Risk of bias was assessed using the Risk of Bias in Non-Randomized Studies of Interventions and Cochrane's risk of bias tools. Descriptive analysis, narrative synthesis, and statistical analysis (via paired t-tests and χ2 independence tests) were performed on relevant article metrics (α = 0.05). RESULTS: We identified a cohort of 45,763 patients from 254 articles. The overall risk of bias was moderate to high. Most articles employed retrospective cohort study designs (37.4%) and were published during the last 2 decades (81.89%). The cohort's average age was 32.5 years (standard deviation, 20.2) with a gender split of ∼3 males per female. Almost 90% of subjects were diagnosed with traumatic brain injury, with road traffic accidents (68.6%) being the greatest cause. Altered consciousness (48.4%) was the most commonly reported clinical feature. Computed tomography (53.5%) was the most commonly used imaging modality, with skull (25.7%) and vertebral fracture (14.1%) being the most common radiological findings for traumatic brain injury and traumatic spinal injury, respectively. Two-thirds of patients were treated nonoperatively. Outcomes were favorable in 63.7% of traumatic brain injury patients, but in only 20.9% of traumatic spinal injury patients. Pressure sores, infection, and motor deficits were the most commonly reported complications in the latter. CONCLUSIONS: This systematic review and pooled analysis demonstrate the significant burden of neurotrauma across Nigeria.

Women in Nigerian Neurosurgery: A Cross-Sectional Survey.

BACKGROUND: Although women have made remarkable strides in several medical specialties in Sub-Saharan Africa, their presence and contribution to the development of neurosurgery remain limited. We sought to study the gender differences within Nigerian neurosurgery, identify challenges resulting from these differences, and recommend how African female neurosurgeons can maximize their effects in neurosurgery. METHODS: A structured online survey captured data on neurosurgical infrastructural capacity, workforce, and training from neurosurgical consultants and residents in neurosurgical centers in Nigeria. All the collected data were coded and analyzed. RESULTS: Altogether, 82 neurosurgical consultants and 67 neurosurgical residents from 50 primary medical institutions in Nigeria completed the online survey. Only 8 of the respondents (5.4%) were women, comprising 3 consultants, 2 senior residents, and 3 junior residents. Although 40.2% of the respondents did not believe that being female affected the decision of whether to specialize in neurosurgery, 46.3% believed that being female was a disadvantage. Most did not believe that being female affected admission (57.8%), completion of a neurosurgery residency (58.5%), or life working as a neurosurgeon after graduation (63.4%). The most common challenges women face while navigating through neurosurgery training and practice are erosion of family and social life, lack of female mentors, and lack of a work-life balance. CONCLUSIONS: There is a deficit of both female consultants and trainees among Nigerian neurosurgeons. Identifying female medical students with a strong interest in neurosurgery and providing early mentorship might increase the number of female neurosurgeons.

A Geospatial Analysis of the Availability, Distribution, and Accessibility of Neurosurgical Facilities, Workforce, and Infrastructure in Nigeria; and Projection Towards 2050.

OBJECTIVE: There has been a modest but progressive increase in the neurosurgical workforce, training, and service delivery in Nigeria in the last 2 decades. However, these resources are unevenly distributed. This study aimed to quantitatively assess the availability and distribution of neurosurgical resources in Nigeria while projecting the needed workforce capacity up to 2050. METHODS: An online survey of Nigerian neurosurgeons and residents assessed the country's neurosurgical infrastructure, workforce, and resources. The results were analyzed descriptively, and geospatial analysis was used to map their distribution. A projection model was fitted to predict workforce targets for 2022-2050. RESULTS: Out of 86 neurosurgery-capable health facilities, 65.1% were public hospitals, with only 17.4% accredited for residency training. Dedicated hospital beds and operating rooms for neurosurgery make up only 4.0% and 15.4% of the total, respectively. The population disease burden is estimated at 50.2 per 100,000, while the operative coverage was 153.2 cases per neurosurgeon. There are currently 132 neurosurgeons and 114 neurosurgery residents for a population of 218 million (ratio 1:1.65 million). There is an annual growth rate of 8.3%, resulting in a projected deficit of 1113 neurosurgeons by 2030 and 1104 by 2050. Timely access to neurosurgical care ranges from 21.6% to 86.7% of the population within different timeframes. CONCLUSIONS: Collaborative interventions are needed to address gaps in Nigeria's neurosurgical capacity. Investments in training, infrastructure, and funding are necessary for sustainable development and optimized outcomes.

Assessing the Neurosurgical Capacity in Nigeria Using the Modified Neuro-PIPES Tool.

BACKGROUND: Like many low- and-middle-income countries in Africa, documented assessment of the neurosurgical workforce, equipment, infrastructure, and scope of service delivery in Nigeria is lacking. This study aimed to assess the capacity for the delivery of neurosurgical services in Nigeria. METHODS: An 83-question survey was disseminated to neurosurgeons and residents in Nigeria. We report the findings from the capacity assessment section of the survey, which used the modified neurological-PIPES (personnel, infrastructure, procedures, equipment, and supplies) (MN-PIPES) tool to evaluate the availability of neurosurgical personnel, infrastructure, procedures, equipment, and supplies. A comparative analysis was done using the domain and total MN-PIPES scores and MN-PIPES index. RESULTS: The national average MN-PIPES score and index were 176.4 and 9.8, respectively. Overall, the southwest and northwest regions had the highest scores and frequently had high subscores. The survey respondents reported that the main challenges impeding neurosurgery service delivery were a lack of adjunctive supplies (75.2%), a dearth of diagnostic and interventional equipment (72.4%), and an absence of a dedicated intensive care unit (72.4%). CONCLUSIONS: The availability of workforce, infrastructure, equipment, and supplies needed to provide optimal neurosurgical care is uneven in many institutions in Nigeria. Although major strides have been made in recent years, targeted collaborative interventions at local, national, regional, and international levels will further improve neurosurgical service delivery in Nigeria and will have positive ripple effects on the rest of the healthcare system.

16(th) IHIW: analysis of HLA population data, with updated results for 1996 to 2012 workshop data (AHPD project report).

We present here the results of the Analysis of HLA Population Data (AHPD) project of the 16th International HLA and Immunogenetics Workshop (16IHIW) held in Liverpool in May-June 2012. Thanks to the collaboration of 25 laboratories from 18 different countries, HLA genotypic data for 59 new population samples (either well-defined populations or donor registry samples) were gathered and 55 were analysed statistically following HLA-NET recommendations. The new data included, among others, large sets of well-defined populations from north-east Europe and West Asia, as well as many donor registry data from European countries. The Gene[rate] computer tools were combined to create a Gene[rate] computer pipeline to automatically (i) estimate allele frequencies by an expectation-maximization algorithm accommodating ambiguities, (ii) estimate heterozygosity, (iii) test for Hardy-Weinberg equilibrium (HWE), (iv) test for selective neutrality, (v) generate frequency graphs and summary statistics for each sample at each locus and (vi) plot multidimensional scaling (MDS) analyses comparing the new samples with previous IHIW data. Intrapopulation analyses show that HWE is rarely rejected, while neutrality tests often indicate a significant excess of heterozygotes compared with neutral expectations. The comparison of the 16IHIW AHPD data with data collected during previous workshops (12th-15th) shows that geography is an excellent predictor of HLA genetic differentiations for HLA-A, -B and -DRB1 loci but not for HLA-DQ, whose patterns are probably more influenced by natural selection. In Europe, HLA genetic variation clearly follows a north to south-east axis despite a low level of differentiation between European, North African and West Asian populations. Pacific populations are genetically close to Austronesian-speaking South-East Asian and Taiwanese populations, in agreement with current theories on the peopling of Oceania. Thanks to this project, HLA genetic variation is more clearly defined worldwide and better interpreted in relation to human peopling history and HLA molecular evolution.

The scope, trends, and challenges of neurosurgical research in Nigeria: A bibliometric review.

OBJECTIVE: This study investigates the scope, trends, and challenges of neurosurgical research in Nigeria since inception of the specialty in 1962. METHODS: A bibliometric review of the neurosurgical literature from Nigeria was done. Variables extracted included year and journal of publication, article topic, article type, research type, study design, article focus area, and limitations. Descriptive and quantitative analyses were performed for all variables. Trends of research publications were described in three periods - pioneering (1962-1981), recession (1982-2001), and resurgent (2002-2021). RESULTS: Of the 1023 included articles, 10.0% were published in the pioneering period, 9.2% in the recession period, and 80.8% in the resurgent period. Papers were predominantly published in World Neurosurgery (4.5%) and Nigerian Journal of Clinical Practice ( 4.0%). 79.9% of the 4618 authors were from Nigerian institutions. 86.3% of the articles covered clinical research and were mainly focused on service delivery and epidemiology (89.9%). The most prominent topics were traumatic brain injury (25.8%) and CNS malignancy (21.4%). Only 4.4% of the publications received funding, mostly from agencies in the US (31.7%). Barriers to neurosurgical research included lack of clinical databases (18.0%), increasing burden of disease (12.5%), and diagnostic challenges (12.4%). CONCLUSION: Neurosurgical research in Nigeria continues to grow due to increased training, workforce, and infrastructural improvements. Addressing the major challenges through establishment of research databases, development of evidence-based management guidelines, and increasing research training, funding and opportunities can increase research capacity in Nigeria.

Profile of pediatric neurosurgery in Nigeria from 1962 to 2021: A systematic review.

OBJECTIVE: This study aims to provide a comprehensive overview of pediatric neurosurgery in Nigeria, since 1962, by assessing epidemiological data, management strategies, and case outcomes. METHODS: A systematic bibliometric review of Nigerian neurosurgical literature was reported with the PRISMA guidelines. The Risk of Bias Assessment Tool was applied to all non-randomized studies, and a descriptive analysis was performed for all variables. RESULTS: We identified 12,295 pediatric patients from 196 published studies. Most publications (72.4%) occurred in the recent two decades, of which 40.3% were observational case reports/series. The patients were predominantly male (57.2%) and aged 0-18 years, with the majority (66.1%) belonging to the 0-5 age range. Most patients (63.4%) presented between 1-12 months. The most common presenting feature was altered consciousness (7.7%), with computed tomography (38.8%) being the most frequently utilized diagnostic imaging modality. The diagnoses with the greatest prevalence (60.2%) were congenital abnormalities such as hydrocephalus and neural tube defects. 57.5% of cases received surgical therapy, with ventriculoperitoneal shunt placement being the most noticeable procedure performed (36.4%). Complications were identified in 9.5% of cases, with a 4.5% death rate. The Glasgow Outcome Score (95.7%) was the primary outcome measure utilized, with positive outcomes reported in 59.3% of cases. CONCLUSION: This review provides significant epidemiological data which emphasizes the country's enormous burden of pediatric neurosurgical cases. The findings can help guide clinical decisions as well as future research and policy development.

The status of specialist neurosurgical training in Nigeria: A survey of practitioners, trainers, and trainees.

OBJECTIVE: Despite the well-known neurosurgical workforce deficit in Sub-Saharan Africa, there remains a low number of neurosurgical training programs in Nigeria. This study sought to re-assess the current status of specialist neurosurgical training in the country. METHODS: An electronic survey was distributed to all consultant neurosurgeons and neurosurgery residents in Nigeria. Demographic information and questions relating to the content, process, strengths, and challenges of neurosurgical training were explored as part of a broader survey assessing neurosurgical capacity. Descriptive statistics were used for analysis. RESULTS: Respondents identified 15 neurosurgical training centers in Nigeria. All 15 are accredited by the West African College of Surgeons (WACS), and 6 by the National Postgraduate Medical College of Nigeria (NPMCN). The average duration of core neurosurgical training was 5 years. Some identified strengths of Nigerian neurosurgical training included learning opportunities provided to residents, recent growth in the neurosurgical training capacity, and satisfaction with training. Challenges included a continued low number of training programs compared to the population density, lack of subspecialty training programs, and inadequate training infrastructure. CONCLUSION: Despite the high number of neurosurgery training centers in Nigeria, compared to other West African countries, the programs are still limited in number and capacity. Although this study shows apparent trainee satisfaction with the training process and contents, multiple challenges exist. Efforts at improving training capacity should focus on continuing the development and expansion of current programs, commencing subspecialty training, driving health insurance to improve funding, and increasing available infrastructure for training.

The role of international collaborations in sustainable neurosurgical development in Nigeria.

OBJECTIVE: Despite six decades of existence, neurosurgery is still in the developing stages in Nigeria. In this era of collaborative health system capacity-building in low- and middle-income countries, this article reviews past efforts and future prospects for collaborative neurosurgical development in Nigeria. METHODS: A bibliometric review of the Nigerian neurosurgical literature and data from a structured survey of Nigerian neurosurgeons and residents provided details of current local and international collaborations for neurosurgical research, service delivery, training, and capacity building. These were analyzed to provide an overview of the role of collaborations in sustainable neurosurgical development in Nigeria and to recommend approaches to enhance neurosurgical capacity. RESULTS: In 1023 peer-reviewed neurosurgery publications from Nigeria, there were 4618 authors with 3688 from 98 Nigerian institutions and 930 from 296 foreign institutions in 70 countries. While there were significant research collaborations amongst Nigerian institutions, the most common were with institutions in the US, UK, and Cameroon. From the survey, 62 of 149 respondents (41.6%) from 32 health facilities noted their institution's involvement in capacity-building neurosurgical collaborations. These collaborations involved 22 Nigerian institutions and 13 foreign institutions in 9 countries and were mostly for training and workforce development (78.1%), and research and data management (59.4%). The majority of foreign institutions were from the US and UK. CONCLUSION: Current and previous neurosurgical collaborations have led to sustainable progress in Nigeria. Further local, regional, and international collaborations would enhance the capacity to address the needs and challenges affecting neurosurgery in Nigeria.

A comparison of the clinical characteristics of women with recurrent major depression with and without suicidal symptomatology.

BACKGROUND: The relationship between recurrent major depression (MD) in women and suicidality is complex. We investigated the extent to which patients who suffered with various forms of suicidal symptomatology can be distinguished from those subjects without such symptoms. METHOD: We examined the clinical features of the worst episode in 1970 Han Chinese women with recurrent DSM-IV MD between the ages of 30 and 60 years from across China. Student's t tests, and logistic and multiple logistic regression models were used to determine the association between suicidality and other clinical features of MD. RESULTS: Suicidal symptomatology is significantly associated with a more severe form of MD, as indexed by both the number of episodes and number of MD symptoms. Patients reporting suicidal thoughts, plans or attempts experienced a significantly greater number of stressful life events. The depressive symptom most strongly associated with lifetime suicide attempt was feelings of worthlessness (odds ratio 4.25, 95% confidence interval 2.9-6.3). Excessive guilt, diminished concentration and impaired decision-making were also significantly associated with a suicide attempt. CONCLUSIONS: This study contributes to the existing literature on risk factors for suicidal symptomatology in depressed women. Identifying specific depressive symptoms and co-morbid psychiatric disorders may help improve the clinical assessment of suicide risk in depressed patients. These findings could be helpful in identifying those who need more intense treatment strategies in order to prevent suicide.

A narrative review of tissue-resident memory T cells and their role in immune surveillance and COVID-19.

Most effector T cells will undergo programmed apoptosis after an immune response and some of them may become memory T cells. According to the distribution and functional status, the memory T cells can be divided into effector central memory T cells (TCM), effector memory T cells (TEM) and tissue-resident memory T cells (TRM) cells. TRM cells, including CD4+ TRM and CD8+ TRM cells, colonize various barrier surfaces and are no longer involved in lymphocyte recycling, closely monitored for local perturbations in homeostasis throughout the body as a critical component of the first defense line. When pathogenic microorganisms invade the body, TRM cells can quickly produce a defense response to initiate innate immunity and adaptive immunity by producing cytokines or killer molecules to resist viral and bacterial infections. In addition, TRM cells are also involved in cancer surveillance and play an essential role in maintaining cancer-immune equilibrium. The high frequency of TRM cells in tumor tissues often means favorable survival for patients. The latest research proves that TRM cells also play an important role in vaccine development and pathological features of COVID-19. This article will summarize the biological functions of TRM cells and aims at providing references for further research on their mechanism and for targeting the best treatment of clinical disease.

A narrative review of pyrolysis and its role in ulcerative colitis.

Cell death is one of the inevitable life activities of cells during the growth and development of the body. Regulated cell death (RCD) is a type of cell death mode that can be regulated and depends on specific molecular mechanisms which play an essential role in various pathophysiological environments. Pyrolysis is a newly discovered method of programmed cell death mediated by members of the Gasdermin protein family which is characterized by the activation of inflammatory factors and the formation of cell membrane pores. The specific manifestations are the swelling of cells, the appearance of plasma membrane bullae and the release of cell contents after cell rupture. A cascade of inflammation occurs after cell death. Activation of inflammasomes activates the classic pyrolysis pathway depending on caspase-1 or the non-classical pyrolysis pathway depending on Caspase-4/5 /11 and the subsequent inflammation reaction, excessive immune response caused by microbial infection and danger signals can lead to a variety of inflammatory diseases. In the inflammatory response, large numbers of inflammasomes activate the substrate protein GSDMD. GSDMD mediates pyrolysis by forming pores in the plasma membrane and mitochondria. Many studies have shown that pyrolysis plays an essential role in inflammatory bowel disease and other inflammatory diseases. This article aims to elaborate on the molecular mechanisms of pyroptosis in ulcerative colitis (UC) pathogenesis and provide new therapeutic ideas for UC.

Analysis of the HLA population data (AHPD) submitted to the 15th International Histocompatibility/Immunogenetics Workshop by using the Gene[rate] computer tools accommodating ambiguous data (AHPD project report).

During the 15th International Histocompatibility and Immunogenetics Workshop (IHIWS), 14 human leukocyte antigen (HLA) laboratories participated in the Analysis of HLA Population Data (AHPD) project where 18 new population samples were analyzed statistically and compared with data available from previous workshops. To that aim, an original methodology was developed and used (i) to estimate frequencies by taking into account ambiguous genotypic data, (ii) to test for Hardy-Weinberg equilibrium (HWE) by using a nested likelihood ratio test involving a parameter accounting for HWE deviations, (iii) to test for selective neutrality by using a resampling algorithm, and (iv) to provide explicit graphical representations including allele frequencies and basic statistics for each series of data. A total of 66 data series (1-7 loci per population) were analyzed with this standard approach. Frequency estimates were compliant with HWE in all but one population of mixed stem cell donors. Neutrality testing confirmed the observation of heterozygote excess at all HLA loci, although a significant deviation was established in only a few cases. Population comparisons showed that HLA genetic patterns were mostly shaped by geographic and/or linguistic differentiations in Africa and Europe, but not in America where both genetic drift in isolated populations and gene flow in admixed populations led to a more complex genetic structure. Overall, a fruitful collaboration between HLA typing laboratories and population geneticists allowed finding useful solutions to the problem of estimating gene frequencies and testing basic population diversity statistics on highly complex HLA data (high numbers of alleles and ambiguities), with promising applications in either anthropological, epidemiological, or transplantation studies.