Introduction The docking button of the Aveir leadless pacemaker (LP) is often difficult to access due to its inappropriate position in the right ventricle (RV). Methods and Results We report a case where the Aveir LP was successfully retrieved by releasing the wedged docking button in the inferior wall of the RV using a loop wire technique. Conclusion The loop wire technique may be useful to change the position of the Aveir LP. This may be helpful to retrieve the Aveir LP even in the case where the docking button is wedged in the inferior wall of the RV.

A document by Katherine Whitehouse. Click on the document to view its contents.

A document by Hala Eldamanhoury. Click on the document to view its contents.

Magnetothermal neuromodulation is a minimally-invasive, deep-brain accessible and tether-free technique. The precisely timed activation of thermosensitive ion channels, such as TRPV1, with local heat generated using magnetic nanoparticles is crucial for efficient neuromodulation. Nevertheless, this technique is greatly hindered by its long stimulus-response time and high safety risks due to the poor heat-generating performance of the nanomediators. Herein, we report the establishment of a ferrimagnetic vortex iron oxide nanoring (FVIO)-mediated magnetothermal neurostimulation technique that is efficient and safe. Compared with widely used superparamagnetic iron oxide nanomediators (SPIOs), the FVIOs triggered Ca2+ influx into HEK293T cells and cortical neurons at an Fe concentration of 54 μg/mL, which is 20.27-fold lower than that needed for SPIOs. In vivo magnetothermal stimulation in the central nucleus of the amygdala of mice further demonstrated that FVIOs with the optimal dose of 0.05 μg evoked fear behaviors with an average latency of 2.51 s, which was 2.3-fold faster than that in the SPIO (0.8 μg)-treated group. More importantly, FVIOs-mediated stimulation not only exhibited negligible histopathological alterations and proinflammatory cytokine expression, but also successfully elicited fear behaviors in transgene-free mice. The FVIO-mediated efficient and safe neuromodulation has the potential for future neuroscience exploitation and neurological disease treatment.

Introduction: The study aims to assess awareness, attitude, apprehension, action expected from policy makers, and acceptability towards HPV vaccination amongst health care providers (HCP), medical students, paramedical staff and administrative personnel. Methods: A cross-sectional study was conducted with 501 participants, including HCP, medical students, paramedical and administrative staff. Their awareness, attitudes, apprehensions, actions expected from policymakers, and acceptability towards HPV vaccine were assessed through a Google Form survey. Results: Of the 501 participants, 92.4% were aware of HPV vaccines, 24.6% had a thorough understanding of HPV, but only 5.8% had received the vaccine. Most participants held a positive attitude toward cervical cancer prevention and HPV vaccination, although 46.7% expressed apprehensions. Initially, 278 participants (55.8%) were willing to receive the HPV vaccine, while 116 (44.2%) were not. After viewing the educational video, willingness increased to 394 participants (78.6%), and those unwilling decreased to 107 (21.4%). Factors such as age, gender, marital status, education, and professional role did not significantly predict knowledge or apprehension regarding HPV and the HPV vaccine. However, professional role and younger adult (20-39 years) groups were statistically significant predictors of a positive attitude as well as stronger expectations for action from policymakers towards HPV vaccine. Conclusion: The study reveals significant gaps in HPV vaccine awareness and uptake among medical professionals, paramedics, and administrative staff. It highlights the need for broad educational programs to address these knowledge gaps, emphasizing HPV’s health impacts and preventive measures. Multimedia educational interventions effectively boost vaccine acceptance among the groups and the general public.

The suprachiasmatic nucleus (SCN) is the master clock that orchestrates circadian clocks across the body to synchronize with and anticipate the earth’s light/dark cycles. Although post-transcriptional regulators called microRNAs have been implicated in physiological SCN function, how the absence of the entire mature miRNome impacts SCN output has not yet been explored. Here, we have generated an SCN-specific Dicer knockout mouse model by crossing Syt10Cre mice with Dicerflox mice to study behavioral consequences of miRNA depletion in the SCN. We show that loss of all mature miRNAs in the SCN shortens the circadian period length by ~40 minutes at the tissue level, and by ~50 minutes at the locomotor activity level. Knockout animals also showed arrythmicity or ultradian locomotor activities with no light masking under constant light, a condition which usually caused lengthening of the circadian period length and reduced activities, i.e. light masking, in nocturnal animals. Moreover, induction of Dicer knockout by Cre injection into the SCN of adult Dicerflox mice eventually resulted in loss of behavioral rhythms. Finally, we show suggestive evidence that SCN desynchronization might be one mechanism underlying the behavioral phenotypes of SCN-specific Dicer knockout animals.

Indoor air pollution represents a major health problem in developing countries. Common sources of household contaminants in these settings include gas or wood-fired stoves and ovens, heaters, fireplaces, tobacco smoke, dust mites, pets, mold, insecticides, and cleaning products. The use of biomass fuels or coal for daily activities, such as cooking, heating and lighting, are still common practices among many Latin American countries because of cultural behaviors, geographical conditions and limited access to cleaner energy sources. Inefficient combustion of these substances results in the release of toxic products, mainly nitrogen dioxide (NO2), carbon monoxide (CO), particulate matter (PM) and volatile organic compounds (VOC). Additionally, tobacco consumption is frequent in the region and is a well-known cause of air pollution, while electronic cigarettes have also gained popularity worldwide and are now a new source of airborne chemicals. Exposure to all these substances has been associated with an increased risk of health issues, particularly in children, such as growth impairment, respiratory infections, asthma, reduced lung function, and development of adult lung diseases (e.g., cancer and COPD) (1).

Our understanding of sexual selection is advancing with new technologies that tag individuals or their sperm, revealing how females use post-copulatory processes to discriminate between competing mates. Many tagging methods have been devised primarily for model insect organisms like Drosophila or Gryllidae. Developing such novel methods, however, is expensive and requires intensive investment. In this experiment, we trial the use of Rhodamine B and Rhodamine 110 in a small arachnid, the bulb mite Rhizoglyphus echinopus, for pre and post copulatory observations as it is a relatively inexpensive and simple way to tag individuals and their ejaculate proteins. First, we tested whether Rhodamine B and Rhodamine 110 applied to food can be used as a tagging method to track and distinguish between individuals. Second, we explored whether Rhodamine applied in this way can be used to track sperm transfer. We found that both tagging probes worked well in tagging individuals and that we were able to distinguish between individuals using both LED and fluorescent microscopy. We also found that Rhodamine degraded rapidly in the animals, likely due to their fast metabolism. Due to the rapid degradation, we observed variable results in the sperm transfer trials. We suggest multiple uses for Rhodamine and highlight other invertebrates where this method may come into use for the study of sexual selection.

Objective: To assess the effectiveness of auditory and visual distraction interventions on patient discomfort, pain and anxiety during office-based Otolaryngologic upper airway procedures. Data Sources: Literature searches were done through Cochrane Central Register of Controlled Trials, Lilacs, MEDLINE, Embase, PsycINFO, and Cumulative Index to Nursing and Allied Health Literature. Review Methods: The protocol was registered in PROSPERO on August 17 th 2022, under Registration number CRD42020204354. Results: We identified 138 records; two randomized controlled trials using virtual reality as a distraction technique in adults and one in children were included. All studies had some concerns regarding risk of bias. In adults, anxiety was lower in the virtual reality group than in the standard of care, (mean difference -16.72, 95% CI -27.19 to -6.24, p=0.002, I 2=0%). There was no difference in procedure related pain between groups, (mean difference -0.28, 95% CI -1.24 to 0.68, p=0.57, I 2=10%). There was no difference in satisfaction between groups (Standardized mean difference 0.18, 95% CI -0.22 to 0.58, p = 0.37, I 2=0%). Only one Pediatric study was included hence no meta-analysis was done. Anxiety and pain were lower and satisfaction was higher in the group using virtual reality. Conclusions: The use of virtual reality distraction in addition to standard analgesia during office-based Otolaryngology upper airway procedures reduced anxiety in adults. It did not decrease pain or increase the level of patient satisfaction. In the paediatric population, there is a reported benefit for procedural anxiety, pain and satisfaction.

Polycatenane gels have attracted extensive attention due to their high degree of freedom and mobility. However, the synthesis of poly[2]catenane gels reported to date all rely on the polymer as the backbone. Herein, we prepared poly[2]catenane gels based on entirely sequential assembly of small molecules. Monomer M1 with two unclosed rings was first prepared, which self-assembled to form supramolecular polymers(SPs) via hydrogen bonding and π-π interactions. Upon adding small molecule monomers M2 and M3 with aldehyde groups, ring closing of SPs occurred due to the amino groups in the SPs reacted with M2 to form imine bonds. In addition, M3, which has twice the number of aldehyde groups as M2, enabled SPs to ring-close, causing the proceeding of crosslinking process at the same time. Thus linear SPs were transformed into poly[2]catenane gel networks. Due to the presence of hydrogen bonds in the poly[2]catenane gel, the gel also possessed stimulus responsiveness and self-healing properties.

A document by Mandana Khodahahi. Click on the document to view its contents.

The bonding across the lattice and ordered structures endow crystals with unique symmetry and determine their macroscopic properties. Crystals with unique properties such as low-dimensional materials, metal-organic frameworks, and defected crystals, in particular, exhibit different structures from bulk crystals and possess exotic physical properties, making them intriguing subjects for investigation. To accurately predict the physical and chemical properties of crystals, it is crucial to consider long-range orders. While GNN excels at capturing the local environment of atoms in crystals, they often face challenges in effectively capturing longer-ranged interactions due to their limited depth. In this paper, we propose CrysToGraph ( Crystals with Transformers on Graph), a novel and robust transformer-based geometric graph network designed for unconventional crystalline systems, and UnconvBench, a comprehensive benchmark to evaluate models’ predictive performance on multiple categories of crystal materials. CrysToGraph effectively captures short-range interactions with transformer-based graph convolution blocks as well as long-range interactions with graph-wise transformer blocks. CrysToGraph proofs its effectiveness in modelling all types of crystal materials in multiple tasks, and moreover, it outperforms most existing methods, achieving new state-of-the-art results on two benchmarks. This work enhances the development of novel crystal materials in various fields, including the anodes, cathodes, and solid-state electrolytes.

Introduction: Leptomeningeal disease (LMD) in diffuse midline gliomas can lead to devastating symptoms such as severe pain, urinary incontinence, and tetraparesis, with limited treatment options. In the present study, we determined whether the detection of H3F3A K27M-mutant droplets in cerebrospinal fluid (CSF) circulating tumor DNA (ctDNA) could serve as a reliable biomarker for the detection of LMD in diffuse midline gliomas. Methods: Twenty-four CSF samples were obtained from 21 diffuse midline glioma patients. Histological confirmation of H3F3A K27M mutation was obtained in 9 (42.8%) cases. ctDNA was extracted from CSF, and H3F3A K27M-mutant and wildtype droplets were detected using digital droplet PCR (ddPCR). LMD was diagnosed by CSF cytology and/or pre- and post-contrast head and whole spine MR imaging. Results: The number of H3F3A K27M-mutant droplets (median 7 [range 0-297] vs median 0 [range 0-2]; p <.0001) and variant allele frequency (VAF) (median 50.0% [range 7.5-87.5%] vs median 0.0% [range 0.0-40.0%]; p <.0001)) were significantly higher in the LMD/early LMD group compared to no LMD group. In two cases (Case 4 and Case 11) without clinical evidence of LMD, multiple H3F3A K27M-mutant droplets were detected in the CSF ctDNA. In those cases, extensive spinal dissemination was detected 175 and 176 days after the initial liquid biopsy. One case (Case 15) with high Schlafen11 (SLFN11) expression in the tumor responded well to treatment for LMD and survived for 532 days after the diagnosis of LMD. Conclusion: This study provides evidence that detecting H3F3A K27M-mutant droplets in CSF ctDNA is diagnostic for LMD and is more sensitive than traditional methods such as CSF cytology and MR imaging.

Two-decade battle with myasthenia gravis: A breakthrough case report on the long-term success of eculizumab and ravulizumab treatment

Prostate cancer is the most common cancer in over 50% of the countries and the third most common malignancy worldwide. The tumor microenvironment denotes the non-cancerous cells and components present in the tumor, including the molecules they produce and release. Prostate cancer proliferation, angiogenesis, metastasis and drug resistance are closely associated with the tumor microenvironment. With the continuous development of in vitro tumor models, they have gradually become an important tool for recapitulating parental tumors in vivo and studying the reciprocal interactions between tumors and their microenvironment. In this review, we describe significant in vitro models of prostate cancer, analyze the research results on incorporating the tumor microenvironment into these models, and compare their advantages and disadvantages. Furthermore, we highlight the future developmental direction of prostate cancer in vitro model research according to the hotspots of in vitro model research in other cancer types to facilitate precision medicine in prostate cancer.

Title: Papillary muscle free strain- promising parameter to predict sudden cardiac death in hypertrophic cardiomyopathy?Author:Dr Aslannif Roslan (MBBS, MRCP)Institut Jantung Negara,50400 Kuala Lumpur,MalaysiaE-mail: [email protected] author:Dr Aslannif Roslan (MBBS, MRCP)Institut Jantung Negara,50400 Kuala Lumpur,MalaysiaE-mail:[email protected] Cardiomyopathy (HCM) generally have a good prognosis. In the long follow-up study over 5 decades annual overall HCM-related mortality was 1.3%/y (0.7% first decade to 1.8% in second and third decades). The sudden cardiac death (SCD) mortality rate was also low (0.1%/y first decade to 0.44% in second and third decades)1. SCD is the most feared HCM complication and the only effective treatment for this is Implantable Cardioverter Defibrillator (ICD) that is responsible for >10-fold decrease in HCM related mortality2. In 2014,the European Society of Cardiology (ESC) come out with risk score comprising 7 variables but this risk score have low sensitivity3,4. This led to the search for additional risk factors such as percentage of late gadolinium enhancement (LGE) in the left ventricle, presence of apical aneurysm and left ventricle ejection fraction <50% .The American Society of Cardiology/American Heart Association (ACC/AHA) incorporate this for their guidelines in 20205.Eventhough this guidelines have high sensitivity, it have low ability to identify low risk patients which can lead to inappropriate ICD implantation4. The ongoing challenge is to identify the small yet significant group of patients who are at risk of sudden cardiac death, heart failure, and death resulting from heart failure.Neither the 2014 nor the 2020 SCD risk calculators/predictors, nor even the latest 2022 ESC guidelines, have incorporated the relatively new echocardiography technique of speckle-tracking strain measurements. This technique is non-doppler oriented, angle independent and have been shown to be highly reproducible with high sensitivity and specificity6. These techniques can measure Global longitudinal strain (GLS), left atrial reservoir (LArS), conduit (LAcS) and booster (LAbS) strain and right ventricle global (RVGLS) and free wall strain (RVFWS). The most studied of these is Global Longitudinal Strain (GLS) and a recent study showed GLS have the highest accuracy to predict fatal arrhythmia and accurate ICD indication compare to all the other echocardiographic parameters that was previously considered important like diastolic left atrial (LA) diameter, left ventricular wall thickness and ejection fraction7.This is consistent with another study of large cohort of 427 HCM patients showing independent association between GLS and all cause mortality, heart transplantation, aborted SCD, and appropriate ICD therapy8. Furthermore, the latest meta-analysis of 13 studies with 2441 HCM patients showed significant correlation between impaired GLS and major adverse cardiovascular outcomes (MACE). The same correlation was also found with LA strain. A recent meta-analysis in 2023 shows significant association between all aspect of LA strain (reservoir, conduit and booster) with MACE as well as development of new atrial fibrillation (AF)9. This is not only true with echocardiography derived strain. In a Cardiac MRI (CMR) strain study published in 2024, the combination of left ventricle circumferential strain and left atrial reservoir strain model shows high diagnostic value of SCD with staggeringly high area under the curve (AUC) of 0.9510. All of these studies show how powerful is strain study in HCM SCD prognosis and it is natural to then look at papillary muscle (PM) strain as this structure is frequently abnormal in HCM11.It is widely known that papillary muscle abnormalities are part of HCM phenotypes, in addition to elongated mitral valve leaflets and hypertrophied muscle with excessive contractility (the sine qua non of HCM)11. Abnormal papillary muscle morphology is independently associated with increase left ventricular outflow tract (LVOT) obstruction with anteroapically displaced PM and double bifid PM patients having higher resting LVOT gradients than control independent of septal thickness, use of rate control medications and resting heart rate12. The variations of papillary muscle abnormalities are anterior and apical displacement of the PM usually involving ALPM, bifid PM characterized by the presence of more than one muscle head (If both PM involved it is called double bifid morphology), accessory PM that extend from the LV apex and inserted to basal myocardium without insertion into the mitral leaflets and anomalous insertion of the PM itself12,13,14.In HCM, the PM are frequently hypertrophied, with a mass measuring roughly twice the healthy controls. HCM patients also tend to have larger number of PM (2.5 muscles vs 2.1 in control) with half of the patients demonstrating multiple (3 or 4) PM15.In this issue of Echocardiography Atilla Koyuncu et al look at 79 patients with HCM that were divided into low/intermediate-risk (n=57, ESC risk score <6 points) and high risk (n=22, ESC risk score ≥6 points) groups based on the ESC risk calculator. Their mean follow-up duration is 6.2 years. They specifically look for PM abnormalities and measured anterolateral papillary muscle (ALPM) and posteromedial papillary muscle (PMPM) free strain in addition to other conventional 2-dimensional echocardiographic parameters and GLS. They enrolled all HCM phenotypic groups with or without obstruction and they exclude patients with hypertension, valvular heart diseases, hepatic/renal failure or inflammatory diseases. Of note, they did not perform left atrium (LA) or right ventricle (RV) strain. Papillary muscle strain is a relatively new tool and the measurements of ALPM strain is done in apical 4 chamber view and measurement for PMPM strain is done in apical 3 chamber view. The majority of patients have sigmoid or reverse curvature phenotype (70.9%). Interestingly 5 patients (6.3%) had anteriorly displaced papillary muscles, 7(8.8%) had bifid ALPM, 5(6.3%) had bifid PMPM and 2 patients have both bifid ALPM and PMPM (double bifid morphology).They found that the high SCD-risk group had greater wall thickness, interventricular septum thickness, posterior wall thickness and left ventricle mass index and lower GLS, ALPM (-16.88 ± 4.41% vs. -14.34 ± 3.68%, p = .028) and PMPM (-18.48 ± 6.31% vs. -15.28 ± 6.88%, p = .042) free strain. Furthermore, the SCD risk score was positively correlated with GLS, ALPM (r=0.658, p<0.001) and PMPM (r=0.600, p<0.001) strain. Also important is the fact that patient who have papillary muscle abnormalities had significantly worse ALPM and PMPM free strain. Finally, in multivariate analysis, LVMI, presence of syncope, worse GLS and ALPM-free strain were predictors of death. In terms of PM free strain value in normal healthy populations, one study done in 2016 shows between -32.5% to -48% for ALPM and -34.5% to -39.5% for PMPM but for the moment at least there are no guidelines for normal values16.What is the relevance of this paper for our understanding of HCM? It introduces an additional parameter that is easy to measure and reproducible alongside GLS and LA strain, aiding in the prediction of SCD. Although the technique is new and the sample size is limited, further studies with larger populations are necessary to establish its predictive value for SCD, similar to GLS. As strain measurements are generally robust and reproducible, papillary muscle strain has the potential to replace traditional parameters like left atrial dimension, wall thickness, and ejection fraction. Moreover, this paper highlights the importance of considering papillary muscle involvement in HCM, drawing attention to abnormalities such as bifid papillary muscles and anterior displacement during strain measurement. Ultimately, by integrating papillary muscle free strain with GLS, RV, and LA strain, we can enhance our ability to predict sudden cardiac death and ensure more appropriate ICD implantation. For clinicians focused on managing HCM, these are exciting times, and this paper provides valuable insights into the field.Maurizi N, Olivotto I, Maron M, et al. Lifetime clinical course of hypertrophic cardiomyopathy: Outcome of the historical Florence cohort over five decades. JACC Adv. 2023;2(4). doi:10.1016/j.jacadv.2023.100337Maron MS, Rowin EJ, Maron BJ. The paradigm of sudden death prevention in hypertrophic cardiomyopathy. Am J Cardiol. 2024;212S:S64-S76. doi:10.1016/j.amjcard.2023.10.076Zeppenfeld K, Tfelt-Hansen J, de Riva M, et al. 2022 ESC guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death. Eur Heart J. 2022;26:ehac262. doi:10.1093/eurheartj/ehac262Monda E, Limongelli G. Integrated sudden cardiac death risk prediction model for patients with hypertrophic cardiomyopathy. Circulation. 2023;147(4):281-283. doi:10.1161/CIRCULATIONAHA.122.063019Ommen SR, Mital S, Burke MA, et al. 2020 AHA/ACC guideline for the diagnosis and treatment of patients with hypertrophic cardiomyopathy: A report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2020;142:e558–e631. doi:10.1161/CIR.0000000000000937Shirani J, Pick R, Roberts WC, Maron BJ. Morphology and significance of the left ventricular collagen network in young patients with hypertrophic cardiomyopathy and sudden cardiac death. J Am Coll Cardiol. 2000;35(1):36-44. doi:10.1016/s0735-1097(99)00492-1Nikoo MH, Zarrabi M, Moaref A, Razeghian-Jahromi I. Global longitudinal strain may be the one that appropriately identifies candidates for ICD implantation. Cardiol Res Pract. 2024;2024:2214072. doi:10.1155/2024/2214072Hiemstra YL, Debonnaire P, Bootsma M, et al. Global longitudinal strain and left atrial volume index provide incremental prognostic value in patients with hypertrophic cardiomyopathy. Circ Cardiovasc Imaging. 2017;10(7): e005706. doi:10.1161/CIRCIMAGING.116.005706Hussain K, Nso N, Tsourdinis G, et al. A systematic review and meta-analysis of left atrial strain in hypertrophic cardiomyopathy and its prognostic utility. Curr Probl Cardiol. 2024;49(1 Pt C):102146. doi:10.1016/j.cpcardiol.2023.102146Zhu X, Shi Y, Lian J, et al. Left atrial and left ventricular strain in feature-tracking cardiac magnetic resonance for predicting patients at high risk of sudden cardiac death in hypertrophic cardiomyopathy. Quant Imaging Med Surg. 2024;14(5):3544-3556. doi:10.21037/qims-23-1615Sherrid MV, Adams DH. The mitral valve in hypertrophic cardiomyopathy: Other side of the outflow tract. J Am Coll Cardiol. 2020;76(19):2248-2251. doi:10.1016/j.jacc.2020.09.580Kwon DH, Setser RM, Thamilarasan M, et al. Abnormal papillary muscle morphology is independently associated with increased left ventricular outflow tract obstruction in hypertrophic cardiomyopathy. Heart. 2008;94(10):1295-1301. doi:10.1136/hrt.2007.118018Klues HG, Maron BJ, Dollar AL, Roberts WC. Diversity of structural mitral valve alterations in hypertrophic cardiomyopathy. Circulation. 1992;85(5):1651-1660. doi:10.1161/01.cir.85.5.1651Gruner C, Chan RH, Crean A, et al. Significance of left ventricular apical-basal muscle bundle identified by cardiovascular magnetic resonance imaging in patients with hypertrophic cardiomyopathy. Eur Heart J. 2014;Rajiah P, Fulton NL, Bolen M. Magnetic resonance imaging of the papillary muscles of the left ventricle: Normal anatomy, variants, and abnormalities. Insights Imaging. 2019;10(1):83. doi:10.1186/s13244-019-0761-3Kılıcgedik A, Kahveci G, Gurbuz AS, et al. Papillary muscle free strain in patients with severe degenerative and functional mitral regurgitation. Arq Bras Cardiol. 2017;108(4):339-346. doi:10.5935/abc.20170035

Facultative scavenging can be observed across a large range of carnivorous mammals, but is an uncommon behavioural trait in cheetahs (Acinonyx jubatus). Very few incidents of cheetahs scavenging have been reported, with no explanation given as to why it may occur. In this paper we provide three more observations of cheetahs scavenging between 2019 and 2023 in three different protected areas in South Africa and Malawi. We suggest a common factor between these observations, namely that all adult individuals involved were temporarily housed in holding enclosures (bomas) during relocation processes and were provisioned with carrion as supplemental feed. The observed scavenging events could also have been influenced by the easy access of food in a situation where food acquisition was potentially difficult (i.e. old age, loss of hunting partner, mother with cubs). We hypothesise that these contributing factors, combined with the prior exposure of the adult individuals to eating carrion, could be a potential explanation for our observations of cheetahs scavenging. These observations provide a basis for further research into cheetah scavenging behaviour and the potential impacts of translocations that require prolonged holding periods on wildlife behaviour post-release. Understanding these behavioural shifts is crucial for cheetah conservation, as successful reintroduction efforts depend on the ability of cheetahs to adapt to new environments and food acquisition strategies.

Recent changes in climate and human land-use have resulted in alterations of the geographic range of many species, including human pathogens. Geographic range expansion and population growth of human pathogens increase human disease risk. Relatively little empirical work has investigated the impact of range changes on within-population variability, a contributor to both colonization success and adaptive potential, during the precise time in which populations are colonized. This is likely due to the difficulties of collecting appropriate natural samples during the dynamic phase of migration and colonization. We systematically collected blacklegged ticks (Ixodes scapularis) across New York State (NY), USA, between 2006 and 2019, a time period coinciding with a rapid range expansion of ticks and their associated pathogens including Borrelia burgdorferi, the etiological agent of Lyme disease. These samples provide a unique opportunity to investigate the genetic dynamics of human pathogens as they expand into novel territory. We observed that founder effects were short-lived, as gene flow from long-established populations brought almost all B. burgdorferi lineages to newly colonized populations within just a few years of colonization. By seven years post-colonization, B. burgdorferi lineage frequency distributions were indistinguishable from long-established sites, indicating that local B. burgdorferi populations experience similar selective pressures despite geographic separation. The B. burgdorferi lineage dynamics elucidate the processes underlying the range expansion and demonstrate that migration into, and selection within, newly colonized sites operate on different time scales.