Serial visual reversal learning in captive black-handed spider monkeys, Ateles geoffroyi.

Recent research suggests that socio-ecological factors such as dietary specialization and social complexity may be drivers of advanced cognitive skills among primates. Therefore, we assessed the ability of 12 black-handed spider monkeys (Ateles geoffroyi), a highly frugivorous platyrrhine primate with strong fission-fusion dynamics, to succeed in a serial visual reversal learning task. Using a two-alternative choice paradigm we first trained the animals to reliably choose a rewarded visual stimulus over a non-rewarded one. Upon reaching a pre-set learning criterion we then switched the reward values of the two stimuli and assessed if and how quickly the animals learned to reverse their choices, again to a pre-set learning criterion. This stimulus reversal procedure was then continued for a total of 80 sessions of 10 trials each. We found that the spider monkeys quickly learned to reliably discriminate between two simultaneously presented visual stimuli, that they succeeded in a visual reversal learning task, and that they displayed an increase in learning speed across consecutive reversals, suggesting that they are capable of serial reversal learning-set formation with visual cues. The fastest-learning individual completed five reversals within the 80 sessions. The spider monkeys outperformed most other primate and nonprimate mammal species tested so far on this type of cognitive task, including chimpanzees, with regard to their learning speed in both the initial learning task and in the first reversal task, suggesting a high degree of behavioral flexibility and inhibitory control. Our findings support the notion that socio-ecological factors such as dietary specialization and social complexity foster advanced cognitive skills in primates.

Nitrate trend reversal in Dutch dual-permeability chalk springs, evaluated by tritium-based groundwater travel time distributions.

Historical use of fertilizer and manure on farmlands is known to have a lasting impact on ecosystems and water resources, but few studies assess the legacy of nitrate pollution on groundwater and surface water after farming applications were reduced. We studied the response of nitrate in spring water to a reduction of nitrogen fertilizer applications in agriculture realized since the mid-1980s. We assessed the travel time distribution of groundwater based on a time series of tritium measurements for 90 springs and small brooks that drain a dual porosity chalk aquifer. The travel time distributions were constrained using the tritium data in combination with time series of nitrate concentrations, applying a shape-free travel time distribution model. A clear trend reversal of nitrate concentrations was observed and simulated for springs with a large fraction of young water (< 30 years old) whereas the nitrate response in springs with relatively older water was attenuated and delayed. We conclude that obtaining a time series of tritium data helps to constrain age distributions of water that is discharged from dual permeability aquifers. The fraction of water aged <30 years was a meaningful parameter to distinguish between different types of springs. Nitrate trends in springs that drain large fractions of young water (> 0.6) show higher peak concentrations, shorter lag-time between leaching and outflow peaks and steeper declines after trend reversal, relative to trends in springs which are dominantly fed by older groundwater. The study thus shows that the nitrate legacy of groundwater systems is strongly determined by the range of their travel time distributions, and trend reversal in receiving springs and surface waters may appear within 10 to 15 years after measures to reduce nitrate losses from farming.

Structurally diverse ent-clerodanoids from the aerial parts of Isodon scoparius.

Scoparodane C (1), a diterpenoid with a rare 3,4-seco-3-nor-2,11-epoxy-ent-clerodane scaffold, was obtained from the aerial parts of Isodon scoparius, along with isocopariusines A-E (2-6), five ent-clerodanoids featuring a 5/6-fused ring system, and isocopariusines F-H (7-9), three common ent-clerodanoids. The structures of these previously undescribed compounds were established by a combination of spectroscopic analysis, X-ray diffraction, chemical derivatization, and quantum chemical calculation. Remarkably, isocopariusine B (3) showed strong resistance reversal activity against fluconazole-resistant Candida albicans.

Geometric Inhibition of Superflow in Single-Layer Graphene Suggests a Staggered-Flux Superconductivity in Bilayer and Trilayer Graphene.

In great contrast to the numerous discoveries of superconductivity in layer-stacked graphene systems, the absence of superconductivity in the simplest monolayer graphene remains quite puzzling. Here, through realistic computation of the electronic structure, we identify a systematic trend that superconductivity emerges only upon alteration of the low-energy electronic lattice from the underlying honeycomb atomic structure. We then demonstrate that this inhibition can result from geometric frustration of the bond lattice that disables the quantum phase coherence of the order parameter residing on it. In comparison, upon deviation from the honeycomb lattice, relief of geometric frustration allows robust superfluidity with nontrivial spatial structures. For the specific examples of bilayer and trilayer graphene under an external electric field, such a bond-centered order parameter would develop superfluidity with staggered flux that breaks the time-reversal symmetry. Our study also suggests the possible realization of the long-sought superconductivity in single-layer graphene via the application of unidirectional strain.

A social learning primacy trend in mate-copying: an experiment in Drosophila melanogaster.

Social learning is learning from the observation of how others interact with the environment. However, in nature, individuals often need to process serial social information and may favour either the most recent information (recency bias), constantly updating knowledge to match the environment, or the information that appeared first in the series (primacy bias), which may slow down adjustment to environmental change. Mate-copying is a widespread form of social learning in a mate choice context related to conformity in mate choice, and where a naive individual develops a preference for a given mate (or mate phenotype) seen being chosen by conspecifics. Mate-copying is documented in most vertebrate taxa and in the fruit fly Drosophila melanogaster. Here, we tested experimentally whether female fruit flies show a primacy or a recency bias by presenting pictures of a female copulating with one of two contrastingly coloured male phenotypes. We found that after two sequential contradictory demonstrations, females show a tendency to prefer males of the phenotype preferred in the first demonstration, suggesting that mate-copying in D. melanogaster is not based on the most recently observed mating and may be influenced by a form of primacy bias.

Discovery of novel pyrazolo[1,5-a]pyrimidine derivatives as potent reversal agents against ABCB1-mediated multidrug resistance.

The P-glycoprotein (ABCB1)-mediated multidrug resistance (MDR) has emerged as a significant impediment to the efficacy of cancer chemotherapy in clinical therapy, which could promote the development of effective agents for MDR reversal. In this work, we reported the exploration of novel pyrazolo [1,5-a]pyrimidine derivatives as potent reversal agents capable of enhancing the sensitivity of ABCB1-mediated MDR MCF-7/ADR cells to paclitaxel (PTX). Among them, compound 16q remarkably increased the sensitivity of MCF-7/ADR cells to PTX at 5 µM (IC50 = 27.00 nM, RF = 247.40) and 10 µM (IC50 = 10.07 nM, RF = 663.44). Compound 16q could effectively bind and stabilize ABCB1, and does not affect the expression and subcellular localization of ABCB1 in MCF-7/ADR cells. Compound 16q inhibited the function of ABCB1, thereby increasing PTX accumulation, and interrupting the accumulation and efflux of the ABCB1-mediated Rh123, thus resulting in exhibiting good reversal effects. In addition, due to the potent reversal effects of compound 16q, the abilities of PTX to inhibit tubulin depolymerization, and induce cell cycle arrest and apoptosis in MCF-7/ADR cells under low-dose conditions were restored. These results indicate that compound 16q might be a promising potent reversal agent capable of revising ABCB1-mediated MDR, and pyrazolo [1,5-a]pyrimidine might represent a novel scaffold for the discovery of new ABCB1-mediated MDR reversal agents.

Comparative host transcriptomics as a tool to identify candidate biomarkers for immune reactions in leprosy using meta-analysis.

Background Leprosy is no longer considered an imprecation, as an effective multidrug therapy regimen is available worldwide for its cure. However, its diverse clinical manifestations sometimes involve acute inflammatory reactions. These complications result in irreversible nerve damage, neuritis and anatomical deformities that emerge before, during the treatment or after the completion of treatment. Reversal reaction (Type-I) and erythema nodosum leprosum (Type-II) are the leprosy reactions generally seen in patients with lepromatous and borderline forms of leprosy. At present, there is no accurate diagnostic test available to detect these leprosy reactions. Objectives To identify potential biomarkers indicative of Type-I and Type-II leprosy reactions that could help in their early diagnosis. Methods and Results Host-transcriptomics investigations have been utilised in this study to decipher a correlation between host-gene expression-based biomarkers and exacerbation of leprosy reactions. We present a comparative analysis of publicly available host transcriptomics datasets (from Gene Expression Omnibus) related to leprosy reactions. Individual datasets were analysed and integration of results was carried out using meta-analysis. Common differentially expressed genes (DEGs) were identified using the frequentist and Bayesian ratio association test methods. We have identified several genes - ADAMTS5, ADAMTS9, IFITM2, IFITM3, KIRREL, ANK3, CD1E, CTSF, DOCK9 and KRT73 to name a few - which can serve as potential biomarkers for Type-II reaction. Similarly, ACP5, APOC1, CCL17, S100B, SLC11A1 among others may likely serve as biomarkers for Type-I reaction. Limitations The number of datasets related to leprosy reactions found after the systematic search is less (n = 4) and may limit the accuracy of identified biomarker genes. This could be resolved by including more studies in the data analysis. Conclusion We provide a comprehensive list of gene candidates which could be prioritised further in research focusing on immune reactions in leprosy, as they are likely important in understanding its complexities and could be useful in its early diagnosis.

Weight at Ostomy Takedown as a Factor to Consider for Operative Timing-Is It Relevant?

Purpose: Weight thresholds have historically determined timing of enterostomy closure (EC) in premature neonates. Recent evidence suggests that neonates less than 2 kg (L2K) can safely undergo EC. We evaluate our single-center experience with performing EC in preterm neonates at L2K versus greater than 2 kg (G2K) at time of EC. Methods: A retrospective review of neonates who underwent EC from January 2018 to 2020 was performed. Neonates who were greater than 90 days at initial operation were excluded. Demographics, clinical characteristics including gestational age (GA) and birth weight (BW), operative reports, and outcomes were reviewed. We compared 30-day complications between neonates who underwent EC at L2K and G2K. We also compared time to full feeds (FF) and postoperative length of stay (LOS). Results: Twenty-four neonates were included: 11 L2K and 13 G2K. The median GA and BW was 25.9 weeks (IQR 2.89) and 805 g (IQR 327), respectively. The most common intraoperative diagnosis during index operation was spontaneous perforation (70%), followed by necrotizing enterocolitis (8.69%). There were no significant differences in GA, BW, or diagnosis, between the L2K versus G2K cohort. We found no difference in complication rates, time to FF (12 days versus 10 days, P = .89), or postoperative LOS (31 days versus 36.5 days, P = .76) between patients who underwent EC at L2K versus G2K, respectively. Conclusion: Although weight gain may be an important indicator of perioperative nutrition status, this study shows that weight alone should not preclude otherwise appropriate patients from undergoing EC.

Mechanisms and regulation of replication fork reversal.

DNA replication is remarkably accurate with estimates of only a handful of mutations per human genome per cell division cycle. Replication stress caused by DNA lesions, transcription-replication conflicts, and other obstacles to the replication machinery must be efficiently overcome in ways that minimize errors and maximize completion of DNA synthesis. Replication fork reversal is one mechanism that helps cells tolerate replication stress. This process involves reannealing of parental template DNA strands and generation of a nascent-nascent DNA duplex. While fork reversal may be beneficial by facilitating DNA repair or template switching, it must be confined to the appropriate contexts to preserve genome stability. Many enzymes have been implicated in this process including ATP-dependent DNA translocases like SMARCAL1, ZRANB3, HLTF, and the helicase FBH1. In addition, the RAD51 recombinase is required. Many additional factors and regulatory activities also act to ensure reversal is beneficial instead of yielding undesirable outcomes. Finally, reversed forks must also be stabilized and often need to be restarted to complete DNA synthesis. Disruption or deregulation of fork reversal causes a variety of human diseases. In this review we will describe the latest models for reversal and key mechanisms of regulation.

Alcohol, flexible behavior, and the prefrontal cortex: Functional changes underlying impaired cognitive flexibility.

Cognitive flexibility enables individuals to alter their behavior in response to changing environmental demands, facilitating optimal behavior in a dynamic world. The inability to do this, called behavioral inflexibility, is a pervasive behavioral phenotype in alcohol use disorder (AUD), driven by disruptions in cognitive flexibility. Research has repeatedly shown that behavioral inflexibility not only results from alcohol exposure across species but can itself be predictive of future drinking. Like many high-level executive functions, flexible behavior requires healthy functioning of the prefrontal cortex (PFC). The scope of this review addresses two primary themes: first, we outline tasks that have been used to investigate flexibility in the context of AUD or AUD models. We characterize these based on the task features and underlying cognitive processes that differentiate them from one another. We highlight the neural basis of flexibility measures, focusing on the PFC, and how acute or chronic alcohol in humans and non-human animal models impacts flexibility. Second, we consolidate findings on the molecular, physiological and functional changes in the PFC elicited by alcohol, that may contribute to cognitive flexibility deficits seen in AUD. Collectively, this approach identifies several key avenues for future research that will facilitate effective treatments to promote flexible behavior in the context of AUD, to reduce the risk of alcohol related harm, and to improve outcomes following AUD.

Reverse and antegrade vector thread lifting techniques: Correcting nasolabial and marionette lines.

BACKGROUND: This study evaluates the efficacy of reverse and antegrade thread lifting vectors in conjunction with thread selection for correcting nasolabial folds and marionette lines, aiming to enhance treatment precision and effectiveness. METHODS: Three female patients aged 43, 48, and 53, presenting with primary concerns regarding nasolabial folds, underwent distinct treatment regimens utilizing various types of threads and vectors. Additionally, video demonstrations were recorded to showcase the procedural techniques employed in each case. RESULTS: The outcomes of the thread lifting procedures demonstrated significant improvements in the correction of the nasolabial fold and marionette line. CONCLUSION: Innovative thread insertion techniques involve entry points above the zygomatic arch and threading toward the temple hairline for lateral face lifting. These utilize barbs to pull skin and underlying tissues. The reversal technique involves inserting threads in a criss-cross pattern, forming a fibrous structure that may prolong the duration of results. Various thread combinations, considering factors such as composition, thickness, and barb size, provide customized procedures. This research introduces clinical applications, including temple area hairline lifting for nasolabial fold and marionette line correction, reverse vectors targeting nasolabial folds and marionette lines, and antegrade approaches from the lateral side.

Hidden care: a qualitative exploration of the roles and responsibilities of language brokers.

This qualitative study explored language brokers' conceptualizations of their roles and responsibilities within the family in Sydney, Australia. Semi-structured interviews were carried out to obtain retrospective accounts of language brokering experiences from 14 self-identified language brokers, 10 females and four males aged between 19 to 49 years (Mean age = 31) who started brokering between ages 7 to 16 (M = 11). Participants were from varied ethnic and socio-cultural backgrounds (Turkish, Lebanese, Filipino, Vietnamese, Chinese and Greek/German). Thematic analysis identified three primary themes: "Hidden Carers: When Parent-Child Roles are Reversed"; "Lost Childhoods: Personal Sacrifice for the Good of the Family"; and "Protecting Parents: Language Brokers as Custodians of Information." Findings revealed that language brokering constitutes a form of hidden caregiving that carries with it several ramifications for the individual and their family. These findings have important implications for future research and policymakers working towards developing culturally responsive interventions that improve the health and wellbeing of language brokers and the resettlement experiences of migrants and their families.

Transcarotid Artery Revascularization Outperforms Transfemoral Carotid Artery Stenting Regardless of Aortic Arch Type or Degree of Atherosclerosis.

OBJECTIVES: The Centers for Medicare and Medicaid Services (CMS) now approve reimbursement for Transfemoral Carotid Artery Stenting (TFCAS) in the treatment of standard-risk patients with carotid artery occlusive disease. TFCAS in patients with complex aortic arch anatomy is known to be challenging with worse outcomes. Transcarotid Artery Revascularization (TCAR) could be a preferable alternative in these patients owing to avoiding the aortic arch and using flow reversal during stent deployment. We aim to compare the outcomes of TCAR versus TFCAS across all aortic arch types and degrees of arch atherosclerosis. METHODS: All patients undergoing Carotid Artery Stenting (CAS) between September 2016 and October 2023 were identified in the VQI database. Patients were stratified into four groups: Group-A (Mild Atherosclerosis and Type I/II Arch), Group-B (Mild Atherosclerosis and Type III Arch), Group-C (Moderate/Severe Atherosclerosis and Type I/II Arch), Group-D (Moderate/Severe Atherosclerosis and Type III Arch). The primary outcome was in-hospital composite stroke or death. ANOVA and χ2tests analyzed differences for baseline characteristics. Logistic regression models were adjusted for potential confounders, and backward stepwise selection was implemented to identify significant variables for inclusion in the final models. Kaplan Meier survival estimates, Log Rank test, and multivariable Cox regression models analyzed hazard ratios for one-year mortality. RESULTS: A total of 20,114 patients were included [Group-A:12,980 (64.53%); Group-B: 1,175 (5.84%); Group-C: 5,124 (25.47%); Group-D: 835 (4.15%)]. TCAR was more commonly performed across the four groups (72.21%, 67.06%, 74.94% 69.22%; p<0.001). Compared to patients with mild arch atherosclerosis, patients with advanced arch atherosclerosis in Group-C and Group-D were more likely to be female, hypertensive, smokers, and have CKD. Patients with Type-III arch in Group-B and Group-D were more likely to present with stroke preoperatively. On multivariable analysis, TCAR had less than half the risk of stroke/death and one-year mortality compared to TFCAS in the patients with the mildest atherosclerosis and simple arch anatomy (group A) (OR=0.43,95%CI:0.31-0.61, p<0.001; HR=0.42,95%CI:0.32-0.57, p<0.001). Group-B patients with similar atherosclerosis but more complex arch anatomy had 70% lower odds of stroke/death with TCAR compared to TFCAS (OR=0.30,95%CI:0.12-0.75, p=0.01). Similar findings were also evident in patients with more severe atherosclerosis and simple arch anatomy (OR=0.66,95%CI:0.44-0.97, p=0.037). There was no significant difference in odds of stroke/death in patients with advanced arch atherosclerosis and complex arch (Group-D) (OR=0.91,95%CI:0.39-2.16, p=0.834). CONCLUSIONS: TCAR is safer than TFCAS in patients with simple and advanced arch anatomy. This could be related to the efficiency of flow reversal vs distal embolic protection. Current CMS decision will likely increase stroke and death outcomes of carotid stenting nationally if multidisciplinary approach and appropriate patient selection are not implemented.

Engineered P2Y12-Overexpressing Cell-Membrane-Wrapped Nanoparticles for the Functional Reversal of Ticagrelor and Clopidogrel.

Antiplatelet agents, particularly P2Y12 receptor inhibitors, are critical medicines in the prevention and treatment of thrombotic diseases in the clinic. However, their long-term use introduces a significant risk of bleeding in patients with cardiovascular diseases. Whether the bleeding is caused by the drug itself or due to surgical procedures or trauma, the need to rapidly reverse the effects of antiplatelet agents in the circulation is essential; however, no such agents are currently available. To address this need, here we describe a strategy that uses cell-membrane-wrapped nanoparticles (CM-NPs) for the rapid reversal of P2Y12 inhibitors. CM-NPs are fabricated with membranes derived from 293T cells genetically engineered to overexpress the P2Y12 receptor. Our findings support the potential of CM-NPs as a strategy for managing bleeding complications associated with P2Y12 receptor inhibitors, offering an approach to improve the safety in the use of these drugs in clinical settings.

Genome editing-based mutagenesis stably modifies composition of wax esters synthesized by Euglena gracilis under anaerobic conditions.

Microalgal oil production represents a promising renewable biofuel source. Metabolic engineering can enhance its utility, transforming it into an improved biofuel and expanding its applications as a feedstock for commodity chemicals, thereby increasing their value in biorefineries. This study focused on anaerobic wax ester production by the microalga Euglena gracilis, aiming to develop stable mutant strains with altered wax ester profiles through genome editing. Two enzymes in the fatty acid beta-oxidation pathway involved in wax ester production were targeted-3-ketoacyl-CoA thiolase and acyl-CoA dehydrogenase-using clustered regularly interspaced short palindromic repeats/Cas9. The results revealed one genetic mutation that lengthened and three that shortened the distribution of wax ester compositions compared to the wild-type (WT). The triple-KO mutant, combining mutations that shorten wax ester chains, produced wax esters with acyl chains two carbons shorter than WT. This study established a methodology to stably modify wax ester composition in E. gracilis.

RTEL1 helicase counteracts RAD51-mediated homologous recombination and fork reversal to safeguard replicating genomes.

Homologous recombination (HR) plays an essential role in the repair of DNA double-strand breaks (DSBs), replication stress responses, and genome maintenance. However, unregulated HR during replication can impair genome duplication and compromise genome stability. The mechanisms underlying HR regulation during DNA replication are obscure. Here, we find that RTEL1 helicase, RAD51, and RAD51 paralogs are enriched at stalled replication sites. The absence of RTEL1 leads to an increase in the RAD51-mediated HR and fork reversal during replication and affects genome-wide replication, which can be rescued by co-depleting RAD51 and RAD51 paralogs. Interestingly, co-depletion of fork remodelers such as SMARCAL1/ZRANB3/HLTF/FBH1 and expression of HR-defective RAD51 mutants also rescues replication defects in RTEL1-deficient cells. The anti-recombinase function of RTEL1 during replication depends on its interaction with PCNA and helicase activity. Together, our data identify the role of RTEL1 helicase in restricting RAD51-mediated fork reversal and HR activity to facilitate error-free genome duplication.

Motion's privilege in recognizing facial expressions following treatment for blindness.

In his 1872 monograph, Charles Darwin posited that "… the habit of expressing our feelings by certain movements, though now rendered innate, had been in some manner gradually acquired."1 Nearly 150 years later, researchers are still teasing apart innate versus experience-dependent contributions to expression recognition. Indeed, studies have shown that face detection is surprisingly resilient to early visual deprivation,2,3,4,5 pointing to plasticity that extends beyond dogmatic critical periods.6,7,8 However, it remains unclear whether such resilience extends to downstream processing, such as the ability to recognize facial expressions. The extent to which innate versus experience-dependent mechanisms contribute to this ability has yet to be fully explored.9,10,11,12,13 To investigate the impact of early visual experience on facial-expression recognition, we studied children with congenital cataracts who have undergone sight-correcting treatment14,15 and tracked their longitudinal skill acquisition as they gain sight late in life. We introduce and explore two potential facilitators of late-life plasticity: the availability of newborn-like coarse visual acuity prior to treatment16 and the privileged role of motion following treatment.4,17,18 We find that early visual deprivation does not preclude partial acquisition of facial-expression recognition. While rudimentary pretreatment vision is sufficient to allow a low level of expression recognition, it does not facilitate post-treatment improvements. Additionally, only children commencing vision with high visual acuity privilege the use of dynamic cues. We conclude that skipping typical visual experience early in development and introducing high-resolution imagery late in development restricts, but does not preclude, facial-expression skill acquisition and that the representational mechanisms driving this learning differ from those that emerge during typical visual development.

Eliminating residual neuromuscular blockade: a literature review.

Background and Objective: Although millions of patients receive neuromuscular blocking agents (NMBAs) each year as part of an anesthetic, residual neuromuscular blockade (NMB) remains a too-frequent occurrence and its adverse consequences continue to negatively impact patient outcomes. The goal of this manuscript is to provide clinicians with the information they need to decrease the incidence of residual NMB. Methods: Published literature was reviewed and incorporated into the narrative as appropriate. Search terms for articles included nondepolarizing NMBAs, residual NMB, monitoring depth of NMB, qualitative monitoring, quantitative monitoring, reversal agents, sugammadex, and anticholinesterases. Key Content and Findings: This review will define what is currently considered adequate recovery of neuromuscular function, discuss and compare the different modalities to determine the depth of NMB, discuss the currently available NMBAs-including their durations of action and dosing, describe the incidence and complications associated with residual NMB, and discuss reversal of nondepolarizing NMB with neostigmine or sugammadex. Nondepolarizing NMBAs are commonly used as part of a general anesthetic. Understanding the pharmacology of the neuromuscular blocking and reversal agent, in combination with quantitative monitoring of depth of NMB is essential to avoid residual paralysis. Conclusions: Quantitative monitoring and dosing of either neostigmine or sugammadex based on the results of monitoring is essential to eliminate residual NMB associated with the use of nondepolarizing NMBAs.

Simplifying vasectomy reversal without compromising outcomes: a single-surgeon series.

Background: In vasovasostomy (VV) surgery, the micro-surgical technique has consistently been shown to provide superior outcomes to both macroscopic and loupe-assisted techniques, with large studies showing overall patency rates of ~86% and pregnancy rates of ~52%. However, the question of whether a single- or double-layer anastomosis offers the best outcomes remains contentious, and despite the popularity of the two-layer technique, a meta-analysis suggests little difference in outcomes. This study records the outcomes of a single-surgeon series of a simplified single-layer technique, along with the comparative outcomes and predictive factors. Methods: A retrospective analysis of 237 consecutive patients undergoing microsurgical vasectomy reversal between 2010 and 2022 in a single institution was performed. A microsurgical, single-layer, six-point, 8-0 nylon anastomosis was performed with macroscopic intra-operative assessment of vasal fluid. An ipsilateral vasoepididymostomy (VE) was only performed in cases of complete absence of vasal fluid or the presence of toothpaste-like discharge (bilateral VE were excluded from this series). Semen analysis was performed 3 months postoperatively to assess for the presence of motile sperm. Results: A total of 237 men underwent microsurgical vasectomy reversal over a 12-year period. The median age of men at vasectomy was 34 years. The median age at vasectomy reversal was 42 years. The median obstructive interval was 7.3 years. An overall patency rate of 85.8% was achieved (motile sperm present), with 53.8% having a sperm count greater than 15 million/mL on initial 3-month assessment. For obstructive intervals of <3, 3-8, 9-14, and ≥15 years, there were declining patency rates of 96.3%, 90.5%, 80.0%, and 74.1%, respectively (P=0.04). These are the equivalent outcomes to published high-volume two-layer studies. We found no difference between patency rates of VV performed on the straight vas vs. the convoluted vas, and no difference when only one side could be re-anastomosed (20 patients). Conclusions: Using a micro-surgical technique in high volume, similar outcomes can be achieved from a simplified single-layer VV technique with fewer sutures, as compared to the more complex two-layer techniques described. We postulate that this may be due to reduced ischaemia relating to fewer sutures and less tissue-handling. Given the associated time and cost savings, as well as the easier learning curve involved, we would advocate the use of this technique in routine VV practise.