Plastid terminal oxidase is required for chloroplast biogenesis in barley.

Chloroplast biogenesis is critical for crop biomass and economic yield. However, chloroplast development is a very complicated process coordinated by cross-communication between the nucleus and plastids, and the underlying mechanisms have not been fully revealed. To explore the regulatory machinery for chloroplast biogenesis, we conducted map-based cloning of the Grandpa 1 (Gpa1) gene regulating chloroplast development in barley. The spontaneous mutation gpa1.a caused a variegation phenotype of the leaf, dwarfed growth, reduced grain yield, and increased tiller number. Genetic mapping anchored the Gpa1 gene onto 2H within a gene cluster functionally related to photosynthesis or chloroplast differentiation. One gene (HORVU.MOREX.r3.2HG0213170) in the delimited region encodes a putative plastid terminal oxidase (PTOX) in thylakoid membranes, which is homologous to IMMUTANS (IM) of Arabidopsis. The IM gene is required for chloroplast biogenesis and maintenance of functional thylakoids in Arabidopsis. Using CRISPR technology and gene transformation, we functionally validated that the PTOX-encoding gene, HORVU.MOREX.r3.2HG0213170, is the causal gene of Gpa1. Gene expression and chemical analysis revealed that the carotenoid biosynthesis pathway is suppressed by the gpa1 mutation, rendering mutants vulnerable to photobleaching. Our results showed that the overtillering associated with the gpa1 mutation was caused by the lower accumulation of carotenoid-derived strigolactones (SLs) in the mutant. The cloning of Gpa1 not only improves our understanding of the molecular mechanisms underlying chloroplast biosynthesis but also indicates that the PTOX activity is conserved between monocots and dicots for the establishment of the photosynthesis factory.

Long-term survival in patients with brain metastases-clinical characterization of a rare scenario.

PURPOSE: This study aimed to assess clinical, treatment, and prognostic features in patients with brain metastases (BM) from solid tumors achieving long-term survival (LTS). Further, the accuracy of diagnosis-specific Graded Prognostic Assessment scores (ds-GPA) to predict LTS was evaluated. METHODS: Patients admitted for radiotherapy of BM between 2010 and 2020 at a large tertiary cancer center with survival of at least 3 years from diagnosis of BM were included. Patient, tumor, treatment characteristics and ds-GPA were compiled retrospectively. RESULTS: From a total of 1248 patients with BM, 61 (4.9%) survived ≥ 3 years. In 40 patients, detailed patient charts were available. Among LTS patients, median survival time from diagnosis of BM was 51.5 months. Most frequent primary tumors were lung cancer (45%), melanoma (20%), and breast cancer (17.5%). At the time of diagnosis of BM, 11/40 patients (27.5%) had oligometastatic disease. Estimated mean survival time based on ds-GPA was 19.7 months (in 8 cases estimated survival < 12 months). Resection followed by focal or whole-brain radiotherapy (WBRT) was often applied (60%), followed by primary stereotactic radiotherapy (SRT) (20%) or WBRT (20%). 80% of patients received systemic treatment, appearing particularly active in specifically altered non-small lung cancer (NSCLC), melanoma, and HER2-positive breast cancer. Karnofsky performance score (KPS) and the presence of oligometastatic disease at BM diagnosis were persisting prognostic factors in LTS patients. CONCLUSION: In this monocentric setting reflecting daily pattern of care, LTS with BM is heterogeneous and difficult to predict. Effective local treatment and modern systemic therapies often appear crucial for LTS. The impact of concomitant diseases and frailty is not clear.

Microbial reconstitution reverses prenatal stress-induced cognitive impairment and synaptic deficits in rat offspring.

Stress during pregnancy is often linked with increased incidents of neurodevelopmental disorders, including cognitive impairment. Here, we report that stress during pregnancy leads to alterations in the intestinal flora, which negatively affects the cognitive function of offspring. Cognitive impairment in stressed offspring can be reproduced by transplantation of cecal contents of stressed pregnant rats (ST) to normal pregnant rats. In addition, gut microbial dysbiosis results in an increase of ß-guanidinopropionic acid in the blood, which leads to an activation of the adenosine monophosphate-activated protein kinase (AMPK) and signal transducer and activator of transcription 3 (STAT3) in the fetal brain. Moreover, ß-guanidinopropionic acid supplementation in pregnant rats can reproduce pregnancy stress-induced enhanced glial differentiation of the fetal brain, resulting in impaired neural development. Using probiotics to reconstruct maternal microbiota can correct the cognitive impairment in the offspring of pregnant stressed rats. These findings suggest that microbial reconstitution reverses gestational stress-induced cognitive impairment and synaptic deficits in male rat offspring.

The impact of coronavirus-19 vaccination on anti-nuclear cytoplasmic antibody vasculitis hospitalisations in a Sydney health network.

There have been reports of COVID-19 vaccination triggering anti-nuclear cytoplasmic antibody (ANCA)-associated vasculitis (AAV), but no robust studies have examined the link. This retrospective cohort study assessed the impact of COVID vaccination on the rate of denovo and relapsed AAV in a Sydney Local Health District from 2018 to 2022. Despite more than 95% of the population receiving vaccination, the case rate of AAV was stable. These findings do not support a relationship between COVID vaccination and AAV.

Avacopan as an additional therapeutic intervention to promote renal recovery in severe ANCA-associated vasculitis: A case report.

Avacopan, a C5a receptor antagonist (C5aR) presents a new therapeutic option to improve outcomes in ANCA-associated vasculitis (AAV). Here we present a case report of a patient initially requiring kidney replacement therapy (KRT), where avacopan was added as an additional adjunctive therapeutic agent late in the treatment course.

Diagnostic and prognostic role of serum interleukin-6 and carotid ultrasonography to detect subclinical atherosclerosis in patients with RA and ANCA-associated vasculitis.

ANCA-associated vasculitis (AAV) can affect multiple organs with severe life-threatening manifestations. Disease monitoring is difficult due to a lack of defined biomarkers. We aimed to assess the diagnostic role of serum interleukin-6 and vascular ultrasonography in AAV and subclinical atherosclerosis. The study included 20 AAV patients and two control groups of 34 patients with rheumatoid arthritis (RA) and 35 healthy controls. The levels of Il-6, carotid intima-media thickness test (CIMT), atherosclerotic plaque, and degree of stenosis were investigated. A GRACE-risk score was calculated for AAV and RA patients. The AAV patients had elevated levels of IL-6 (115 ± 23.96) compared to the RA patients (91.25 ± 42.63) and the healthy controls (15.65 ± 3.30), p < 0.001. IL-6 showed a diagnostic accuracy of 73% in distinguishing AAV from RA patients (AUC = 0.730; 95% CI 0.591 to 0834). In the AAV group, CIMT was 1.09, above the upper reference value of 0.90, p < 0.001. The AAV patients had a higher median GRACE risk score, and 60% of them had a high risk of cardiovascular events as compared to 35% of the RA patients. Sonography of extracranial vessels and serum levels of IL-6 can be used in daily clinical practice to diagnose and monitor patients with AAV.

When inflammation is not just inflammation-A review of systemic diseases of the nose and sinuses part 2: Granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis.

BACKGROUND: Chronic rhinosinusitis is a very common condition. Granulomatosis with polyangiitis (GPA) and eosinophilic granulomatosis with polyangiitis (eGPA) are systemic diseases which can contribute to the development of chronic rhinosinusitis in select patients. OBJECTIVE: Characterize the presenting features, diagnostic criteria, workup, and management of granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis as they are encountered in otolaryngology clinics. METHODS: Full length manuscripts published 2000 or later were reviewed. A separate search was conducted for each disease. Pertinent clinical features related to sinonasal manifestations of GPA and eGPA were collected and reported in this review. RESULTS: 467 references were discovered during literature review process. In total, 42 references for GPA and 35 references for eGPA were included in this review. CONCLUSION: GPA and eGPA are vasculitis syndromes which commonly present in the context of multisystem disease. For GPA, pulmonary and renal disease are common; for eGPA a history of asthma is nearly ubiquitous. Sinonasal disease is a very common feature for both disease processes and may precede the development of systemic symptoms in many patients. Clinical work up and diagnosis is complex and generally requires multidisciplinary care. Treatment primarily consists of immunosuppressive agents, and a number of steroids, steroid sparing agents, and biologics have been shown to be effective. The role of sinus surgery includes tissue biopsy for diagnosis, functional surgery for symptom management in select cases, and reconstruction of cosmetic and functional defects.

[Novel admission procedure for medical students leads to equal opportunities for the individuals-but may aggravate the shortage of rural doctors]. / Neues Zulassungsverfahren Humanmedizin: höhere individuelle Gerechtigkeit, aber Verstärkung des Landarztmangels?

BACKGROUND: In 2017, the Federal Constitutional Court ruled several aspects of the German student admission process unconstitutional. Consequently, the waiting time quota was replaced by an aptitude quota in 2020. Students are now allowed to simultaneously apply to all German medical faculties and an adjustment algorithm for school leaving grades from different federal states was introduced. The present study investigates the impact of these changes on the new study cohorts. METHODS: Records from the federal admission trust were used to compare the final two winter semesters before the change to the first three thereafter. RESULTS AND DISCUSSION: The impact of the new procedure on students with previous medical training cannot yet be conclusively assessed. While grade point average (GPA) and sex of the students remained comparable and students still prefer to study close to home; however, they have become younger. The adjustment for school leaving grades indeed led to equal opportunities for the individual applicant; however, this may aggravate the shortage of rural doctors. The current adjustment mechanism considers applicant numbers, yet less people apply from rural areas while at the same time these areas suffer from a shortage of physicians. As rural upbringing and education are the best predictors of rural practice after licensing, the shortage may worsen. To counteract this, the compensation mechanism for the school leaving grades could easily be adjusted.

Life, death and resurrection of plant GPCRs.

The activation of G-protein coupled receptors (GPCRs) by extracellular ligands constitutes the first step of heterotrimeric G-protein signalling in animals. In plants, canonical GPCRs have been known for over 25 years, often in association with agronomically important functions. But their role in plant G-protein signalling and even their annotation as GPCR was contested in the last decade, only to be revisited in the light of more recent evidences. In this first ever review on plant GPCRs, we catalogue all the plant GPCRs described to date and discuss the evidences for and against their role in plants in general and G-protein signalling in particular. We argue against writing off GPCRs and point to the missing links to be investigated to establish firm conclusions either way.

Regulatory B cells are reduced in the blood in patients with granulomatosis with polyangiitis, and fail to regulate T-cell IFN-γ production.

Regulatory B (Breg) cells can dampen inflammation, autoreactivity, and transplant rejection. We investigated the frequencies, phenotypes, and function of Breg cells in granulomatosis with polyangiitis (GPA) to gain further knowledge as to whether there are numerical alterations or limitations of their ability to regulate T-cell function. Frequencies and phenotypes of CD24hiCD27+ and CD24hiCD38hi B-cells in the blood were determined with flow cytometry in 37 GPA patients (22 in remission and 15 with active disease) and 31 healthy controls (HC). A co-culture model was used to study the capacity of Breg cells to regulate T-cell activation and proliferation in cells from 10 GPA patients in remission and 12 HC. T-cell cytokine production in vitro and levels in plasma were determined with enzyme-linked immunosorbent assay. Frequencies of CD24hiCD27+ B-cells were reduced both during active disease and remission compared with HC (P = 0.005 and P = 0.010, respectively), whereas CD24hiCD38hi B-cells did not differ. Patient CD24hiCD27+ B-cells exhibited decreased expression of CD25 but increased expression of PD-L1 and PD-L2 during remission. B-cells from GPA patients regulated T-cell proliferation but failed to regulate interferon (IFN)-γ production (median T-cells alone 222 ng/ml vs. T-cells + B-cells 207 ng/ml, P = 0.426). IFN-γ was also elevated in patient plasma samples (P = 0.016). In conclusion, GPA patients exhibit altered numbers and phenotypes of CD24hiCD27+ B-cells. This is accompanied by a disability to control T-cell production of Th1-type cytokines during remission, which might be of fundamental importance for the granulomatous inflammation that characterizes the chronic phase of this disease.

Metabolic engineering of the shikimate pathway in Amycolatopsis strains for optimized glycopeptide antibiotic production.

Glycopeptide antibiotics (GPA) consist of a glycosylated heptapeptide backbone enriched in aromatic residues originating from the shikimate pathway. Since the enzymatic reactions within the shikimate pathway are highly feedback-regulated, this raises the question as to how GPA producers control the delivery of precursors for GPA assembly. We chose Amycolatopsis balhimycina, the producer of balhimycin, as a model strain for analyzing the key enzymes of the shikimate pathway. A. balhimycina contains two copies each of the key enzymes of the shikimate pathway, deoxy-d-arabino-heptulosonate-7-phosphate synthase (Dahp) and prephenate dehydrogenase (Pdh), with one pair (Dahpsec and Pdhsec) encoded within the balhimycin biosynthetic gene cluster and one pair (Dahpprim and Pdhprim) in the core genome. While overexpression of the dahpsec gene resulted in a significant (>4-fold) increase in balhimycin yield, no positive effects were observed after overexpression of the pdhprim or pdhsec genes. Investigation of allosteric enzyme inhibition revealed that cross-regulation between the tyrosine and phenylalanine pathways plays an important role. Tyrosine, a key precursor of GPAs, was found to be a putative activator of prephenate dehydratase (Pdt), which catalyzes the first step reaction from prephenate to phenylalanine in the shikimate pathway. Surprisingly, overexpression of pdt in A. balhimycina led to an increase in antibiotic production in this modified strain. In order to demonstrate that this metabolic engineering approach is generally applicable to GPA producers, we subsequently applied this strategy to Amycolatopsis japonicum and improved the production of ristomycin A, which is used in diagnosis of genetic disorders. Comparison of "cluster-specific" enzymes with the isoenzymes from the primary metabolism's pathway provided insights into the adaptive mechanisms used by producers to ensure adequate precursor supply and GPA yields. These insights further demonstrate the importance of a holistic approach in bioengineering efforts that takes into account not only peptide assembly but also adequate precursor supply.

Evaluation of the ACR/EULAR 2022 criteria for classification of ANCA-associated vasculitis in a population-based cohort from Sweden.

OBJECTIVE: To evaluate the ACR/EULAR 2022 criteria for AAV classification and compare it to the EMA algorithm and to classification based only on ANCA serology. METHODS: In the analysis, 374 cases (47% female) were classified according to EMA algorithm, ANCA serology, and ACR/EULAR criteria. The agreement rate was calculated using the kappa (κ) statistic. RESULTS: Under EMA, 192 patients were classified as GPA, 159 as MPA, and 23 as EGPA. The ACR/EULAR criteria classified 199 patients as GPA, 136 as MPA, and 22 as EGPA. Four patients (1.1%) met criteria of two disease categories, and thirteen (3.5%) were unclassifiable. The observed agreement between EMA and ACR/EULAR was 85% for GPA, 75% for MPA, and 96% for EGPA. The unweighted κ statistic was 0.66 (95% CI 0.60-0.74). Of the 188 PR3-ANCA-positive patients, 186 (98.9%) were classified as GPA using ACR/EULAR criteria, and 135 of 161 (83.8%) MPO-ANCA-positive patients were classified as MPA. With a classification solely based on ANCA-specificity, agreement with ACR/EULAR was 99% for GPA and 88% for MPA. CONCLUSIONS: EMA and ACR/EULAR classification give similar results. A small proportion of patients cannot be classified or fall into two categories. Some patients exhibiting granuloma, a key feature of GPA, are nevertheless classified as MPA, conflicting with the current view of histopathology of AAV. There is high agreement of ANCA-based classification with that of ACR/EULAR, reflected in the considerable weight granted to ANCA in the new criteria. These crucial elements within the new criteria necessitate a consensus discussion among field experts.

Translational implications of humoral and cellular immune dysfunction in granulomatosis with polyangiitis.

Granulomatosis with polyangiitis (GPA) is a rare systemic ANCA (Anti-neutrophil cytoplasmic antibodies) associated vasculitis (AAV). In the last couple of decades, GPA has emerged as a disease of concern due to rapid increase in the prevalence and incidence especially in developing countries. Unknown aetiology and rapid progression have made GPA a critical disease. Thus, establishing specific tools to facilitate early and faster disease diagnosis and efficient disease management has immense importance. GPA may develop in genetically predisposed individuals on receiving the external stimulus (i.e. microbial pathogen, pollutant etc.) that triggers the immune response. B-cell activating factor (BAFF) produced by the neutrophils, promotes the B-cell maturation and survival which leads to increased ANCA production. Abnormal B-cell and T-cell proliferation and their cytokine response plays a major role in disease pathogenesis and granuloma formation. ANCA interacts with neutrophils and induces the neutrophil extracellular traps (NETs) formation and reactive oxygen species (ROS) production which leads to the endothelial cell injury. This review article summarizes the critical pathological events and how cytokines and immune cells shape the GPA pathogenesis. Decoding this complex network would facilitate in developing tools for diagnosis, prognosis and disease management. Recently developed specific monoclonal antibodies (MAbs) targeting cytokines and immune cells are being used for safer treatment and achieving longer remission.

Differential enzymatic deglycosylation reveals attachment of red cell B antigen onto the carbohydrate moiety of glycophorin A and glycophorin B.

BACKGROUND AND OBJECTIVES: Early studies indicate that red cell A and B antigens are attached primarily onto band 3 and GLUT1 on the erythrocyte membrane and little onto glycophorin A (GPA) and glycophorin B (GPB). But as GPA and band 3 form stable protein complexes and GPA is much more heavily glycosylated than band 3, this study re-examined the association between ABO antigens and GPA/GPB. MATERIALS AND METHODS: Band 3/GPA-associated protein complexes were first immunoprecipitated, followed by differential enzymatic deglycosylation that removed sialic acids, N-glycans and O-glycans. Serological anti-A (BIRMA 1) and anti-B IgM (GAMA 110) could be used for western blot (WB); however, only the anti-B IgM showed significant reactivity for the immunoprecipitates isolated by anti-band 3. The expression of the B antigen in un-deglycosylated and differentially deglycosylated band 3 immunoprecipitates was thus compared. RESULTS: Besides attachment to band 3, red cell B antigen expressed substantially on GPA monomer and homodimer, GPA*GPB heterodimer, and GPB monomer and dimer via attachments through the N- and O-glycans. CONCLUSION: Immunoprecipitation (IP), as a means of protein separation and concentration, was used in combination with a WB to differentiate glycosylation on different proteins and oligomers. This study implemented differential enzymatic deglycosylation during IP of the band 3 complexes. This combined approach allowed separate identification of the B antigen on GPA/GPB monomer and dimer and GPA*GPB heterodimer, and band 3 on the WB and verified non-trivial expression of the B antigen on GPA and GPB on the erythrocyte surface.

Two- and three-dimensional endoscopic endonasal surgery of large and giant pituitary adenomas-outcome analysis of a series of 62 patients from a single pituitary center.

To analyze the perioperative course and clinical outcome of patients with large (lPA) and giant (gPA) pituitary adenoma who underwent endoscopic endonasal transsphenoidal surgery (EETS) using either two-dimensional (2D-E) or three-dimensional (3D-E) endoscopic systems. Single-center retrospective study of consecutive patients with lPA and gPA who underwent EETS between November 2008 and January 2023. LPA were defined as ≥ 3 cm and < 4 cm in diameter in at least one dimension and a volume of ≥ 10ccm; gPA were defined as larger than 4 cm in diameter and with a greater volume than 10ccm. Patient data (age, sex, endocrinological and ophthalmological status) and tumor data (histology, tumor volume, size, shape, cavernous sinus invasion according to the Knosp classification) were analyzed. 62 patients underwent EETS. 43 patients were treated for lPA (69.4%) and 19 patients for gPA (30.6%). 46 patients (74.2%) underwent surgical resection using 3D-E and 16 patients 2D endoscopy (25.8%). Statistical results are referred to the comparison between 3D-E and 2D-E. Patients' age ranged from 23-88 years (median 57), 16 patients were female (25.8%), 46 male (74.2%). Complete tumor resection was possible in 43.5% (27/62), partial resection in 56.5% (35/62). Resection rates did not differ between 3D-E (27 patients [43.5%]) and 2D-E (7 patients [43.8%], (p = 0.985). Visual acuity improved in 30 of 46 patients with preoperative deficit (65.2%). In the 3D-E group 21 of 32 patients (65.7%) improved, compared to 9 of 14 patients in the 2D-E group (64.3%). Improvement of visual field was achieved in 31 of 50 patients (62.0%; 22 of 37 patients in the 3D-E group [59.4%] and 9 of 13 patients in the 2D-E group [69.2%]). CSF leak was the most frequent complication and occurred in 9 patients (14.5%, [8 patients 17.4% 3D-E]) without statistical significance. Other surgical complications like postoperative bleeding, infection (meningitis) and deterioration of visual acuity and field were detected without statistical difference. New pituitary anterior lobe dysfunction was observed in 30 of 62 patients (48.4%, 8 patients [50.0%] in the 2D-E group and 22 patients [47.8%] in the 3D-E group). A transient deficit of posterior lobe was detected in 22.6% (14/62). No patient died within 30 days of surgery. Although 3D-E may improve surgical dexterity, in this series of lPA and gPA it was not associated with higher resection rates compared to 2D-E. However, 3D-E visualization during resection of large and giant PA is safe and feasible and patient's clinical outcome is not different compared to 2D-E.

Mindfulness and Academic Performance of College and University Students: A Systematic Review.

Higher education's expectations place demands on students' attainment, leading them to experience stress and anxiety, which negatively affect their academic improvement and life satisfaction. The aim of this systematic review was to investigate (a) if mindfulness as an inner ability is related to academic attainment, through dependent variables, including compassion, engagement, stress or anxiety state, depression, self-efficacy, mindfulness's facets (non-reactivity, acting with awareness) and (b) if mindfulness-based interventions positively affect the academic performance of college and university students. The systematic review was conducted in accordance with the PRISMA statement. PubMed, Web of Science, and Cochrane Library Wiley were screened to identify studies published relevant to the topic. In total, 568 papers were retrieved in the initial search. Five papers met the eligibility criteria and were included in the systematic review: a randomized controlled trial, a non-randomized controlled trial, a quasi-experimental study, a quantitative exploratory pilot study, and a longitudinal randomized controlled study. Most interventional studies revealed a non-significant direct effect of practicing mindfulness technique on academic attainment. Further research, especially randomized controlled trials are necessary to clarify the effect of mindfulness on academic performance of college and university students.

Polyvictimization and Academic Performance: Findings From a National-Level Study of College Students.

Research on polyvictimization (i.e., experiencing multiple types of victimization) suggests that its effects are diverse and may be more severe than the effects of single-type victimization. Few studies have focused on polyvictimization among college students and how its experience may shape academic life. Thus, this study examines how polyvictimization (i.e., sexual, violent, and stalking-in the last 12 months) among college students relates to academic performance. Participants (N = 67,972) were drawn from the Spring 2019 administration of the American College Health Association's National College Health Assessment II. Findings show that polyvictims' grade point averages are lower than nonpolyvictims and polyvictims have higher odds of having their academic performance suffer connected to a variety of factors (mental health, physical health, and substance use). Students who experienced three types of victimization (compared to fewer) had the highest odds of having their academic performance harmed. These findings suggest extra attention be paid to polyvictimization as it relates to factors that shape academic performance.

Orbital biopsy findings consistent with granulomatosis polyangiitis in a 14-year-old boy with Crohn's disease.

Both granulomatous polyangiitis (GPA) and Crohn's disease (CD) can cause orbital inflammation though rarely coincide and can often be differentiated by presenting features and histological findings. Here, we report the clinical and therapeutic course of a 14-year-old White male with binocular diplopia caused by orbital myositis. Imaging and biopsy obtained at presentation revealed necrosis and necrotizing granulomatous vasculitis suspicious for GPA. He subsequently developed gastrointestinal symptoms and terminal ileitis consistent with CD. Orbital symptoms responded well to high-dose steroids and remained quiet on methotrexate maintenance therapy. While clinical history, thorough physical exam, and complete laboratory work-up are essential in the management of pediatric orbital myositis, orbital biopsy can prove critical for diagnosis and suitable treatment strategy.

Predictors of clinical performance in comprehensive care cases in undergraduate dentists.

INTRODUCTION: Achieving a high grade in the final-year comprehensive clinical care (CCC) course is not only important for the individual candidate but also to ensure competency of students as they transition from dental school into independent practice. Here, we aimed to identify predictors of success in the CCC that might prove useful to identify which, if any, students need focused intervention to improve their performance in the CCC. MATERIALS AND METHODS: This was a cross-sectional study of two consecutive cohorts (2017-2018 and 2018-2019) of final-year (Year six) dental students (n = 180 females and n = 150 males) attending [King Abdulaziz University], Saudi Arabia. Age, gender, cumulative GPA to the start of Year six and assessment results were tabulated and analysed as independent variables in binary logistic regression to identify predictors of the final case grade (≤69% or >70%). RESULTS: Year five GPA (OR 1.07, 95% CI 1.02-1.12; p = .004) and female gender (OR 2.21, 95% CI 1.12-4.36; p = .02) were significantly associated with an increased odds of achieving a final case grade >70%. In particular, female students were over twice as likely as male students to achieve a higher score in their final case assessment. DISCUSSION: This study suggests that gender may influence final performance in the CCC. The better performance of females in the final CCC course than their male counterparts suggests that there may be a narrowing or even reversal of the historical gender gap in dental school performance. CONCLUSIONS: Both cognitive (GPA) and other (i.e. gender) factors influence clinical dental performance. Further work is required to establish what instructional modifications are required to accommodate these gender differences in CCC courses to pave the way for personalised teaching approaches to optimise educational outcomes.

Impact of a First-Year Place-Based Learning Community on STEM Students' Academic Achievement in their Second, Third, and Fourth Years.

Learning communities for college students have been shown to improve first-year student outcomes and narrow equity gaps, but longer-term data to evaluate whether these benefits persist through multi-year retention and graduation are rare. This is especially important for students in science, technology, engineering and math, who often confront gateway courses and challenging academic cultures in their second and subsequent years. Here, we report on the second, third, and fourth year academic outcomes of three cohorts of a first-year placed-based learning community. Relative to a reference group, participants in the learning community generally showed similar grade acquisition in second- and third-year STEM courses, and initially higher GPAs for learning community participants later diminished to be statistically indistinguishable from the reference group. Nonetheless, units completed after one, two, and three years were slightly higher for learning community participants than for the reference group, and with narrower equity gaps. The learning community also increased and narrowed equity gaps in second- and third-year retention at the institution and in STEM specifically (+6 to +17%). Four-year graduation rates from the institution and in STEM specifically also increased (+8 to +17%), but equity gaps were only narrowed slightly. These results suggest that while benefits of first-year learning communities on grades decline over time, benefits for retention and graduation can persist, though they are insufficient to erase equity gaps. Future work should examine how scaffolding practices in students' second and third years can better sustain and even magnify inclusive success improvements initiated by first year learning communities.