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Background and Objectives: Inherited metabolic disorders (IMDs), primarily cystinosis, Fabry disease, and methylmalonic acidemia (MMA), are genetic conditions that typically result in multi-organ disease manifestations. Kidney function progressively deteriorates in many cases, with patients eventually reaching end-stage kidney disease (ESKD) and requiring renal replacement therapy. Kidney transplantation has been deemed the optimal renal replacement therapy option to achieve long-term survival in patients with IMD. Whilst improved long-term survival is expected, the patterns of clinical evolution for IMD after transplantation remain largely unknown. Methods: Our group conducted a retrospective observational study that included 37 adult patients with IMD (11 with cystinosis, 20 with Fabry disease, and 6 with MMA). The study evaluated the clinical status and progression of these patients following kidney transplantation between January 2010 and December 2023. Results: This generally resulted in good graft outcomes for patients with IMD. Standard immunosuppression regimes included tacrolimus, mycophenolate mofetil, and prednisolone. The mean graft survival duration was noted to be 12 years in patients with cystinosis, 11 years in patients with Fabry disease, and 7 years in patients with MMA. Suboptimal outcomes were noted with grafts of cadaveric origin and poor adherence to the prescribed post-transplant immunosuppression regime. A greater extra-renal morbidity burden was associated with a reduced duration of graft function and increased mortality in patients with IMD. Conclusions: Our findings emphasise the need for a multi-disciplinary approach in the care of IMD patients following kidney transplantation.

The human gut microbiota constitutes a complex community of microorganisms residing within the gastrointestinal tract, encompassing a vast array of species that play crucial roles in health and disease. The disease processes involved in chronic kidney disease (CKD) and end-stage kidney disease (ESKD) are now increasingly established to result in dysregulation of gut microbiota composition and function. Gut microbiota dysbiosis has been associated with poor clinical outcomes and all-cause mortality in patients with ESKD, particularly individuals receiving dialysis. Prior studies highlighted various factors that affect gut microbiota dysbiosis in CKD and ESKD. These include, but are not limited to, uraemic toxin accumulation, chronic inflammation, immune dysfunction, medications, and dietary restrictions and nutritional status. There is a lack of studies at present that focus on the evaluation of gut microbiota dysbiosis in the context of dialysis. Knowledge on gut microbiota changes in this context is important for determining their impact on dialysis-specific and overall outcomes for this patient cohort. More importantly, evaluating gut microbiota composition can provide information into potential targets for therapeutic intervention. Identification of specific microbial signatures may result in further development of personalised treatments to improve patient outcomes and mitigate complications during dialysis. Optimising gut microbiota through various therapeutic approaches, including dietary adjustments, probiotics, prebiotics, medications, and faecal transplantation, have previously demonstrated potential in multiple medical conditions. It remains to be seen whether these therapeutic approaches are effective within the dialysis setting. Our review aims to evaluate evidence relating to alterations in the gut microbiota of patients undergoing dialysis. A growing body of evidence pointing to the complex yet significant relationship which surrounds gut microbiota and kidney health emphasises the importance of gut microbial balance to improve outcomes for individuals receiving dialysis.

Multiple Ras proteins, including N-Ras, depend on a palmitoylation/depalmitoylation cycle to regulate their subcellular trafficking and oncogenicity. General lipase inhibitors such as Palmostatin M (Palm M) block N-Ras depalmitoylation, but lack specificity and target several enzymes displaying depalmitoylase activity. Here, we describe ABD957, a potent and selective covalent inhibitor of the ABHD17 family of depalmitoylases, and show that this compound impairs N-Ras depalmitoylation in human acute myeloid leukemia (AML) cells. ABD957 produced partial effects on N-Ras palmitoylation compared with Palm M, but was much more selective across the proteome, reflecting a plasma membrane-delineated action on dynamically palmitoylated proteins. Finally, ABD957 impaired N-Ras signaling and the growth of NRAS-mutant AML cells in a manner that synergizes with MAP kinase kinase (MEK) inhibition. Our findings uncover a surprisingly restricted role for ABHD17 enzymes as regulators of the N-Ras palmitoylation cycle and suggest that ABHD17 inhibitors may have value as targeted therapies for NRAS-mutant cancers.

BackgroundCommercial genetic tests for type 2 polysaccharide storage myopathy (PSSM2) and myofibrillar myopathy (MFM) have not been validated by peer-review, and formal regulation of veterinary genetic testing is lacking.ObjectivesTo compare genotype and allele frequencies of commercial test variants (P variants) in MYOT (P2; rs1138656462), FLNC (P3a; rs1139799323), FLNC (P3b; rs1142918816) and MYOZ3 (P4; rs1142544043) between Warmblood (WB) and Arabian (AR) horses diagnosed with PSSM2/MFM by muscle histopathology, and phenotyped breed-matched controls. To quantify variant frequency in public repositories of ancient and modern horse breeds.Study designCross sectional using archived clinical material and publicly available data.MethodsWe studied 54 control-WB, 68 PSSM2/MFM-WB, 30 control-AR, 30 PSSM2/MFM-AR and 205 public genotypes. Variants were genotyped by pyrosequencing archived DNA. Genotype and allele frequency, and number of variant alleles or loci were compared within breed between controls, PSSM2/MFM combined and MFM or PSSM2 horses considered separately using additive/genotypic and dominant models (Fisher's exact tests). Variant frequencies in modern, early domestic and Przewalski horses were determined from a public data repository.ResultsThere was no significant association between any P locus and a histopathological diagnosis of PSSM2/MFM, and no difference between control and myopathic horses in total loci with alternative alleles, or total alternate alleles when PSSM2/MFM was considered combined or separately as PSSM2 or MFM. For all tests, sensitivity was

Purpose Of the three currently recognized variants of primary progressive aphasia, behavioral differentiation between the nonfluent/agrammatic (nfvPPA) and logopenic (lvPPA) variants is particularly difficult. The challenge includes uncertainty regarding diagnosis of apraxia of speech, which is subsumed within criteria for variant classification. The purpose of this study was to determine the extent to which a variety of speech articulation and prosody metrics for apraxia of speech differentiate between nfvPPA and lvPPA across diverse speech samples. Method The study involved 25 participants with progressive aphasia (10 with nfvPPA, 10 with lvPPA, and five with the semantic variant). Speech samples included a word repetition task, a picture description task, and a story narrative task. We completed acoustic analyses of temporal prosody and quantitative perceptual analyses based on narrow phonetic transcription and then evaluated the degree of differentiation between nfvPPA and lvPPA participants (with the semantic variant serving as a reference point for minimal speech production impairment). Results Most, but not all, articulatory and prosodic metrics differentiated statistically between the nfvPPA and lvPPA groups. Measures of distortion frequency, syllable duration, syllable scanning, and-to a limited extent-syllable stress and phonemic accuracy showed greater impairment in the nfvPPA group. Contrary to expectations, classification was most accurate in connected speech samples. A customized connected speech metric-the narrative syllable duration-yielded excellent to perfect classification accuracy. Discussion Measures of average syllable duration in multisyllabic utterances are useful diagnostic tools for differentiating between nfvPPA and lvPPA, particularly when based on connected speech samples. As such, they are suitable candidates for automatization, large-scale study, and application to clinical practice. The observation that both speech rate and distortion frequency differentiated more effectively in connected speech than on a motor speech examination suggests that it will be important to evaluate interactions between speech and discourse production in future research.

Background: To determine if school engagement is a viable target for early prevention of adolescent substance use, this study investigated whether school engagement in early adolescence (ages 12-14) is a cause of alcohol and cannabis use during middle to late adolescence (ages 15-19). Methods: To facilitate causal inference, inverse probability of treatment weights (IPTWs), which are based on estimated probabilities of treatment selection (ie, school engagement), were created based on a robust set of potential confounders. Using the IPTWs, a cumulative link mixed model was fit to examine the impact of school engagement on alcohol and cannabis use among an ethnically diverse sample of adolescents (N = 360). Results: School engagement was associated with a lower level of alcohol and cannabis use from age 15 to 18. School engagement was not associated with change in alcohol and cannabis use over time, suggesting that school engagement emits its effect early in the developmental course of substance use and offers protection throughout adolescence. Conclusions: This study supports a compensatory role of early school engagement in substance use across middle and late adolescence. School engagement is a malleable factor and thus offers an avenue for prevention efforts.

Introduction: Kidney transplantation is the preferred modality of kidney replacement therapy for eligible patients with end-stage kidney disease (ESKD), given that it has been found to reduce mortality rates, improve quality of life, and is cost-effective compared to dialysis. Recent advancements in human leukocyte antigen (HLA) typing and donor-specific antibody (DSA) detection have helped to reduce the risk of rejection, but antibody-mediated rejection (AMR) can still occur without DSA. Previous studies suggest that rejection can be attributed to antibodies against Non-Human Leucocyte Antigens (non-HLAs). We aimed to acquire further understanding of the prevalence and distribution of non-HLA antibodies in our local population and attempt to correlate these findings with graft outcomes, as well as assess whether non-HLA antibodies can be utilized to determine graft impairment and dysfunction. Methods: We conducted a retrospective study involving kidney transplant recipients between January 2010 and December 2020. All included individuals were aged over 18 and underwent kidney-alone transplants; were ABO- and HLA-compatible; and were matched at A, B, and DR loci (mismatch 0:0:0). HLA testing was negative at the time of transplantation. The samples from both cases of early graft rejection and the control group were tested for non-HLA antibodies using One Lambda LABScreenTM, Autoantibody kit groups 1, 2, and 3, as well as the Immucor LIFECODES non-HLA autoantibody assay. Results: A total of 850 kidney transplant recipients were included, in which 12 patients experienced early graft rejection within the first month post transplant and 18 patients who did not experience graft rejection were selected as study controls. Our study reported no correlation between the total burden of non-HLA antibodies and early rejection, most likely as the result of a small sample size. Nevertheless, a sub-analysis revealed that specific high-frequency pre-transplant non-HLA antibodies such as GSTT, CXCL11, CXCL10, and HNR, detected by LIFECODES, were associated with rejection (Fisher’s exact test with Bonferroni correction, p < 0.001). Most pre-transplant non-HLA antibody levels were reduced after transplantation, which was attributed to immunosuppression. Conclusion: The ‘high frequency’ non-HLA antibodies displayed an association with graft rejection, though the overall associations between the burden of non-HLA antibodies and rejection episodes remain inconclusive. Further work is needed to establish the rebound phenomenon of non-HLA antibodies, the development of de novo non-HLA antibodies in the long run, and their implications on graft survival.

Anomia is an early and prominent feature of primary progressive aphasia (PPA) and other neurodegenerative disorders. Research investigating treatment for lexical retrieval impairment in individuals with progressive anomia has focused primarily on monolingual speakers, and treatment in bilingual speakers is relatively unexplored. In this series of single-case experiments, 10 bilingual speakers with progressive anomia received lexical retrieval treatment designed to engage relatively spared cognitive-linguistic abilities and promote word retrieval. Treatment was administered in two phases, with one language targeted per phase. Cross-linguistic cognates (e.g., rose and rosa) were included as treatment targets to investigate their potential to facilitate cross-linguistic transfer. Performance on trained and untrained stimuli was evaluated before, during, and after each phase of treatment, and at 3, 6, and 12 months post-treatment. Participants demonstrated a significant treatment effect in each of their treated languages, with maintenance up to one year post-treatment for the majority of participants. Most participants showed a significant cross-linguistic transfer effect for trained cognates in both the dominant and nondominant language, with fewer than half of participants showing a significant translation effect for noncognates. A gradual diminution of translation and generalization effects was observed during the follow-up period. Findings support the implementation of dual-language intervention approaches for bilingual speakers with progressive anomia, irrespective of language dominance.

Logopenic variant primary progressive aphasia (lvPPA) is a neurodegenerative language disorder primarily characterized by impaired phonological processing. Sentence repetition and comprehension deficits are observed in lvPPA and linked to impaired phonological working memory, but recent evidence also implicates impaired speech perception. Currently, neural encoding of the speech envelope, which forms the scaffolding for perception, is not clearly understood in lvPPA. We leveraged recent analytical advances in electrophysiology to examine speech envelope encoding in lvPPA. We assessed cortical tracking of the speech envelope and in-task comprehension of two spoken narratives in individuals with lvPPA (n = 10) and age-matched (n = 10) controls. Despite markedly reduced narrative comprehension relative to controls, individuals with lvPPA had increased cortical tracking of the speech envelope in theta oscillations, which track low-level features (e.g., syllables), but not delta oscillations, which track speech units that unfold across a longer time scale (e.g., words, phrases, prosody). This neural signature was highly correlated across narratives. Results indicate an increased reliance on acoustic cues during speech encoding. This may reflect inefficient encoding of bottom-up speech cues, likely as a consequence of dysfunctional temporoparietal cortex.

IntroductionThe effect of bilingualism on age at onset has yet to be examined within different clinical variants of Alzheimer's disease.MethodsWe reviewed the research charts of 287 well-characterized participants with either amnestic Alzheimer's dementia or logopenic variant primary progressive aphasia (lvPPA) and identified bilingual speakers based on regular use of two or more languages and/or ability to communicate with native speakers in two or more languages. We evaluated whether bilingual speakers demonstrated a delay in age of symptom onset relative to monolingual speakers while controlling for other variables known to influence cognitive reserve.ResultsA 5-year delay in age at symptom onset was observed for bilingual relative to monolingual speakers with lvPPA. This delay in onset was not observed in the amnestic Alzheimer's dementia cohort.DiscussionBilingualism may serve as a unique cognitive reserve variable in lvPPA, but not in amnestic Alzheimer's dementia.

While transgender and gender non-binary (trans/nb) individuals are disproportionately affected by HIV, pre-exposure prophylaxis (PrEP) uptake remains low in this underserved population. We conducted four focus groups with 37 trans/nb individuals in San Diego and Los Angeles to assess barriers and facilitators of PrEP usage. Transcripts were coded for qualitative themes. Although overall PrEP awareness was high, participants reported limited knowledge and misinformation about PrEP. Barriers to PrEP use included: structural access (e.g., discrimination from health care providers, lack of trans-inclusive services, financial barriers), mental health struggles limiting ability to access PrEP, and concerns about potential side effects, drug-drug interactions with hormone therapy, and lack of other STI protection. Facilitators of PrEP usage included: increased PrEP availability, prior experience taking daily medications, and motivation to have active and healthy lives without fear of contracting HIV. Addressing both structural and psychosocial/behavioral factors in trans-affirming health care environments is crucial to designing inclusive, effective PrEP interventions.

PurposeDiagnosis and classification of primary progressive aphasia (PPA) requires confirmation of specific speech and language symptoms, highlighting the important role of speech-language pathologists (SLPs) in the evaluation process. The purpose of this case report is to inform SLPs regarding current practices for diagnostic assessment in PPA, describing standard approaches as well as complementary, state-of-the-art procedures that may improve diagnostic precision.   MethodWe describe the diagnostic evaluation of a 49-year old female with complaints of progressive word-finding difficulty. She completed standard neurological, neuropsychological, and speech-language evaluations, as well as magnetic resonance and positron emission tomography imaging of her brain. In addition, a history of developmental speech, language, and learning abilities was obtained, as well as genetic testing, and assessment of cerebrospinal fluid biomarkers. We discuss the evaluation results in the context of the most current research related to PPA diagnosis.   ConclusionDetailed behavioral assessment, thorough intake of symptom history and neurodevelopmental differences, multimodal neuroimaging, and comprehensive examination of genes and biomarkers are of paramount importance for detecting and characterizing PPA, with ramifications for early behavioral and/or pharmacological intervention.

We present the hitherto largest sample of gas-phase metallicity radial gradients measured at sub-kpc resolution in star-forming galaxies in the redshift range of z ∈ [1.2, 2.3]. These measurements are enabled by the synergy of slitless spectroscopy from the Hubble Space Telescope near-infrared channels and the lensing magnification from foreground galaxy clusters. Our sample consists of 76 galaxies with stellar mass ranging from 107 to 1010 M⊙, an instantaneous star formation rate in the range of [1, 100] M⊙ yr-1, and global metallicity [1/12 ,2] of solar. At a 2σ confidence level, 15/76 galaxies in our sample show negative radial gradients, whereas 7/76 show inverted gradients. Combining ours and all other metallicity gradients obtained at a similar resolution currently available in the literature, we measure a negative mass dependence of Δlog(O/H)/Δ r [dex kpc-1] = (-0.020 ± 0.007) + (-0.016 ± 0.008), with the intrinsic scatter being σ = 0.060 ± 0.006 over 4 orders of magnitude in stellar mass. Our result is consistent with strong feedback, not secular processes, being the primary governor of the chemostructural evolution of star-forming galaxies during the disk mass assembly at cosmic noon. We also find that the intrinsic scatter of metallicity gradients increases with decreasing stellar mass and increasing specific star formation rate. This increase in the intrinsic scatter is likely caused by the combined effect of cold-mode gas accretion and merger-induced starbursts, with the latter more predominant in the dwarf mass regime of M∗ ≤ 109 M⊙.

ContextEarly tailored transplant education could help patients make informed transplant choices.ObjectiveWe interviewed 40 patients with chronic kidney disease (CKD) stages 3 to 5, 13 support persons, and 10 providers at Kaiser Permanente Southern California to understand: (1) barriers to transplant education and (2) transplant educational preferences and recommendations based on CKD stage and primary language spoken.DesignA grounded theory analysis identified central themes related to transplant education barriers, preferences, and recommendations.ResultsBarriers included confusion about diagnosis and when transplant may be necessary, concerns about transplant risks, families' lack of transplant knowledge, financial burdens, transportation and scheduling, and the emotional overload of chronic illness. Hispanic and Spanish-speaking participants reported difficulty in understanding transplant education and medical mistrust. Recommendations included providing general education, earlier introduction to transplant, wait-listing information, transplant education for support persons, living donation education for patients and potential donors, opportunities to meet living donors and kidney recipients, information on the benefits of transplant, recovery, and available financial resources, flexible class scheduling, online and print resources, and more provider follow-up. Spanish-speaking and Hispanic participants recommended using bilingual educators, print, video, and online resources in Spanish, and culturally responsive education. Patients with CKD stages 3 to 4 wanted information on slowing disease progression and avoiding transplant.ConclusionIncreasing access to culturally responsive transplant education in multiple languages, pairing appropriate content to the disease stage, and increasing system-wide follow-up as the disease progresses might help patients make more informed choices about transplant.

Digital information storage capacity and biomedical technology advancements in recent decades have stimulated the maturity and popularization of “big data” in medicine. The value of utilizing big data as a diagnostic and prognostic tool has continued to rise given its potential to provide accurate and insightful predictions of future health events and probable outcomes for individuals and populations, which may aid early identification of disease and timely treatment interventions. Whilst the implementation of big data methods for this purpose is more well-established in specialties such as oncology, cardiology, ophthalmology, and dermatology, big data use in nephrology and specifically chronic kidney disease (CKD) remains relatively novel at present. Nevertheless, increased efforts in the application of big data in CKD have been observed over recent years, with aims to achieve a more personalized approach to treatment for individuals and improved CKD screening strategies for the general population. Considering recent developments, we provide a focused perspective on the current state of big data and its application in CKD and nephrology, with hope that its ongoing evolution and revolution will gradually identify more solutions to improve strategies for CKD prevention and optimize the care of patients with CKD.

Merkel cell carcinoma (MCC) is an uncommon form of skin neoplasm with poor histological differentiation and an aggressive disease process, leading to high recurrence and mortality. There are multiple risk factors in which being in an immunocompromised state is a significant factor, and the discovery of Merkel cell polyomavirus (MCPyV) since 2008 has strengthened causal associations between MCC and immunosuppression. Individuals who have undergone kidney transplantation are therefore more susceptible to having MCC, secondary to post-transplant immunosuppression which plays a vital role in reducing the risk of transplant kidney rejection. Over recent years a rise in the incidence of MCC following kidney transplantation is noted, with increased reporting of such cases. Whilst localized MCC is observed, MCC metastasis to the lymphatic system, brain, bone, liver, lung, and heart has been previously observed in patients with transplanted kidneys. Kidney metastasis is less common and has been only reported in recent years with greater frequency. The management of aggressive, metastatic MCC has historically been palliative, and prognosis is poor. Recently, the use of immune checkpoint inhibitors for metastatic MCC in multi-center phase II clinical trials have shown promising survival outcomes and have been approved for use in countries such as the United States as a first-line treatment. In this review we will explore the potential pathophysiological processes of MCC manifesting post-kidney transplantation. We will then evaluate the epidemiology of MCC within the context of kidney transplantation, before discussing the various clinical presentations, diagnostic measures, surveillance strategies, and current treatment options as well as future directions to best manage MCC in kidney transplant recipients.

Peritonitis is a common and potentially serious complication of peritoneal dialysis (PD). Common organisms include Staphylococcus Aureus, enterococci, and coagulase-negative staphylococcus. However, Stenotrophomonas maltophilia (S. maltophilia) is an uncommon cause of PD-related infection. We describe a series of three cases of S. maltophilia PD infection (two cases of PD peritonitis and one case of PD exit-site infection) that were identified over a seven-week period in a single centre. The cases were treated with antibiotics (the primary antibiotic being co-trimoxazole) for a mean duration of 30 ± 7.9 days. All of the patients required PD catheter removal due to treatment failure with antibiotics. Hospital admission was required in two of the cases and one case resulted in mortality, with the cause of death directly associated with complications from S. maltophilia infection. A multi-disciplinary team using root-cause analysis did not identify a common link between our cases but highlighted possible risk factors contributing to these presentations. Given the relative rarity of S. maltophilia, evidence on its management options remains limited. In this article, we draw upon our own experiences and examine the literature available from previously published case reports and series. These reports highlight S. maltophilia as a complex and challenging organism to treat. Our experience demonstrated the importance of early PD catheter removal in S. maltophilia PD infection, as this is likely more effective than prolonged antibiotic therapy and hence a safer management option, considering the resistant nature of S. maltophilia.