Perinatal risk factors and neurocognitive outcomes in children and adolescents with sickle cell disease.

BACKGROUND: The literature on cognitive and academic outcomes for children with sickle cell disease (SCD) who experience perinatal risk factors is limited. We aimed to evaluate if low birthweight (LBW), gestational age, and history of neonatal intensive care unit (NICU) admission were associated with neurocognitive functioning, grade retention, or receipt of early intervention or formal educational support in children with SCD. PROCEDURES: This prospective birth cohort study included 336 participants, ages 8-18, with SCD, who received cognitive testing as part of standard of care and whose caregivers completed behavioral rating scales. Multivariable generalized linear regression models were used to examine associations between perinatal risks and outcome variables, after adjusting for demographic and medical covariates. RESULTS: The prevalence of NICU admission and LBW were 12.03% and 13.50%, respectively. Lower birthweight, earlier gestational age, and NICU admission were associated with worse working memory performance and receipt of early intervention services. Lower birthweight and NICU admission were also associated with slower processing speed. History of NICU admission was associated with caregiver ratings of hyperactivity and emotional dysregulation. The effects of perinatal risk factors on neurocognitive, academic, or educational outcomes were not dependent on SCD genotype. CONCLUSIONS: History of LBW or NICU admission was associated with worse cognitive outcomes and increased use of early intervention services among children with SCD. Early identification of perinatal risk factors will help identify children who will benefit from formal developmental or neuropsychological evaluations to manage the comorbidity of SCD and perinatal risks and facilitate increased intervention.

PAR1-mediated Non-periodical Synchronized Calcium Oscillations in human Mesangial Cells.

Mesangial cells offer structural support to the glomerular tuft and regulate glomerular capillary flow through their contractile capabilities. These cells undergo phenotypic changes, such as proliferation and mesangial expansion, resulting in abnormal glomerular tuft formation and reduced capillary loops. Such adaptation to the changing environment is commonly associated with various glomerular diseases, including diabetic nephropathy and glomerulonephritis. Thrombin-induced mesangial remodeling was found in diabetic patients, and expression of the corresponding protease-activated receptors (PARs) in the renal mesangium was reported. However, the functional PAR-mediated signaling in mesangial cells was not examined. This study investigated protease-activated mechanisms regulating mesangial cell calcium waves that may play an essential role in the mesangial proliferation or constriction of the arteriolar cells. Our results indicate that coagulation proteases like thrombin induce synchronized oscillations in cytoplasmic Ca2+ concentration of mesangial cells. The oscillations required PAR1 GPCRs-related activation, but not a PAR4, and were further mediated presumably through store-operated calcium entry and TRPC3 channel activity. Understanding thrombin signaling pathways and their relation to mesangial cells' contractile or synthetic (proliferative) phenotype may play a role in the development of chronic kidney disease and requires further investigation.

SHIELD: Skull-shaped hemispheric implants enabling large-scale electrophysiology datasets in the mouse brain.

To understand the neural basis of behavior, it is essential to measure spiking dynamics across many interacting brain regions. Although new technologies, such as Neuropixels probes, facilitate multi-regional recordings, significant surgical and procedural hurdles remain for these experiments to achieve their full potential. Here, we describe skull-shaped hemispheric implants enabling large-scale electrophysiology datasets (SHIELD). These 3D-printed skull-replacement implants feature customizable insertion holes, allowing dozens of cortical and subcortical structures to be recorded in a single mouse using repeated multi-probe insertions over many days. We demonstrate the procedure's high success rate, biocompatibility, lack of adverse effects on behavior, and compatibility with imaging and optogenetics. To showcase SHIELD's scientific utility, we use multi-probe recordings to reveal novel insights into how alpha rhythms organize spiking activity across visual and sensorimotor networks. Overall, this method enables powerful, large-scale electrophysiological experiments for the study of distributed neural computation.

Early intermediates in bacterial RNA polymerase promoter melting visualized by time-resolved cryo-electron microscopy.

During formation of the transcription-competent open complex (RPo) by bacterial RNA polymerases (RNAPs), transient intermediates pile up before overcoming a rate-limiting step. Structural descriptions of these interconversions in real time are unavailable. To address this gap, here we use time-resolved cryogenic electron microscopy (cryo-EM) to capture four intermediates populated 120 ms or 500 ms after mixing Escherichia coli σ70-RNAP and the λPR promoter. Cryo-EM snapshots revealed that the upstream edge of the transcription bubble unpairs rapidly, followed by stepwise insertion of two conserved nontemplate strand (nt-strand) bases into RNAP pockets. As the nt-strand 'read-out' extends, the RNAP clamp closes, expelling an inhibitory σ70 domain from the active-site cleft. The template strand is fully unpaired by 120 ms but remains dynamic, indicating that yet unknown conformational changes complete RPo formation in subsequent steps. Given that these events likely describe DNA opening at many bacterial promoters, this study provides insights into how DNA sequence regulates steps of RPo formation.

Prevalence of limbal stem cell deficiency at an academic referral center over a two-year period.

Aim: To evaluate the prevalence and clinical characteristics of limbal stem cell deficiency (LSCD) in the setting of a tertiary referral cornea practice at an academic center. Patient and methods: A retrospective chart review was performed to identify all unique medical record numbers (MRNs) presenting to a single cornea specialist (JHH) at the University of Minnesota during calendar years 2019 and 2020. Records were queried and confirmed for a diagnosis of LSCD. Clinical characteristics of identified patients, including demographics, etiology of LSCD, severity of LSCD, treatment, and best corrected visual acuity (BCVA) at final follow-up, were documented. Results: In total 1436 unique MRNs were identified over the study period. There were 61 individuals (91 eyes) diagnosed with LSCD, resulting in a prevalence of 4.25% (95% CI, 3.33-5.42). Of 91 eyes, 60 eyes were bilateral (65.9%). Among all eyes, ocular surface burns were the most common etiology (18.7%) followed by iatrogenic or medicamentosa (15.4%). There were 51 eyes (56.0%) that underwent some form of transplantation. The median BCVA at final follow-up was Snellen 20/80 (range 20/20 to no light perception). Conclusions: The prevalence of LSCD found at a cornea subspecialty tertiary referral center in our study was much higher than previously reported prevalence rates. This may reflect referral bias and potential underdiagnosis of LSCD in practices outside of subspecialty referral centers. The high prevalence rate in our study also suggests that LSCD patients are concentrated in subspecialty referral practices, with many having high morbidity disease. This constitutes a major health burden for these practices.

Comparison of Post-hemorrhoid Surgery Pain Profiles in Older and Younger Adults.

INTRODUCTION: Older and younger adults are offered similar analgesic options after hemorrhoid surgery (HS), but the differences in pain between the two populations are unknown. This study aims to compare postoperative pain outcomes after HS in older and younger individuals. METHODS: This is a retrospective analysis of electronic medical records of patients who underwent HS between 2018 and 2023. Patients were excluded if additional anorectal procedures were performed at the time of HS. Data related to pain-related outcomes were compiled: (1) need for narcotic prescription refills; (2) documentation of a pain-related phone call within 30 d; (3) urgent postoperative office visit before regular scheduled follow-up; and (4) pain-related postoperative emergency department visits. Associations between age and pain-related outcomes were tested using Fisher's exact test, chi-square test, and covariate adjusted logistic regression modeling. RESULTS: There were a total of 249 patients, 60 older adults, and 189 younger adults. Compared to younger patients, older adults demonstrated a reduced frequency of pain-related phone calls (10.3 versus 32.1%, P < 0.01) and opioid refills (0 versus 14.4%, P < 0.01). After adjusting for confounders, older age remained inversely associated with pain-related postoperative phone calls (odds ratio = 0.25, 95% confidence interval = [0.1-0.6], P = 0.003). CONCLUSIONS: Older adults had better pain outcomes after HS in comparison to younger patients. These findings suggest that the postoperative analgesic needs of older patients after HS are lower than those of younger patients. Decisions regarding opioid prescription in older adults recovering from HS should be tailored to avoid narcotic-related complications.

Decompressive craniectomy in symptomatic intracerebral hemorrhage after ischemic stroke: a multicenter retrospective cohort study.

OBJECTIVE: Symptomatic intracerebral hemorrhage (sICH) after stroke is a devastating neurological complication. Current guidelines support a "possible benefit" of decompressive craniectomy (DC) for large supratentorial sICH with significant mass effect. METHODS: The authors conducted a retrospective study of 8 comprehensive stroke centers. They included all patients who sustained an sICH after acute ischemic stroke (AIS), as defined by the Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST), from January 2016 to December 2020. They compared patients who underwent DC to those who were treated with standard medical treatment to measure functional outcome at 90 days, primarily as defined by the modified Rankin Scale (mRS) and secondarily by the Glasgow Outcome Scale-Extended (GOS-E). RESULTS: Eighty-five patients were identified, 26 of whom (30.5%) underwent DC. Patients who underwent DC were younger (58 years [DC] vs 76 years [no DC], p < 0.001). No patient with a previous history of cancer underwent DC (n = 14, p = 0.004). Twenty-five patients (96.2%) in the DC group underwent thrombectomy versus 54 (91.5%) in the non-DC group (p = 0.443). Patients who underwent DC had a longer ICU stay (median [IQR] 240 [38-408] hours vs 24 [5-96] hours in non-DC patients, p = 0.002). At 90 days, 3 patients (4.1%) had obtained an mRS score of 0-2 and 10 patients (11.7%) an mRS score of 0-3. Patients who had improved functional outcome were younger (mRS score, OR 1.06, 95% CI 1.01-1.10, p = 0.012). Patients with a history of cancer had worse 90-day mRS scores (OR 8.49, 95% CI 1.54-159, p = 0.046). The rate of in-hospital mortality or discharge to hospice was significantly higher in the non-DC cohort (10 [38.5%] patients in the DC cohort vs 38 [64.4%] in the non-DC cohort, p = 0.026). Ninety days later, patients who underwent DC were more likely to have improved outcome (mRS mean rank 30.0 vs 40.0, p = 0.027). In multivariable analysis, history of cancer (OR 12.2, 95% CI 1.26-118, p = 0.031) and older age (OR 1.07, 95% CI 1.02-1.13, p = 0.011) increased the odds of worse mRS outcomes while DC did not (OR 1.34, 95% CI 0.357-5.03, p = 0.665). CONCLUSIONS: DC after sICH did not improve functional outcome at 90 days according to multivariable analysis, although younger age and absence of previous cancer history were associated with improved outcomes.

Reduced Violence-Related Burden and Mortality at Higher Altitudes: Examining the Association between High Altitude Living and Homicide Rates in Ecuador.

Esteban Ortiz-Prado, Juan Sebastian Izquierdo-Condoy, María G. Dávila-Rosero, Jorge Vásconez-González, Ana M. Diaz, Carla E. Moyano, Vanessa Arcos-Valle, Ginés Viscor, and Joshua H. West. Reduced Violence-Related Burden and Mortality at Higher Altitudes: Examining the Association between High Altitude Living and Homicide Rates in Ecuador. High Alt Med Biol. 00:000-000, 0000. Background: Homicides are a major public health concern and a leading cause of preventable deaths worldwide. The relationship between altitude and homicides remains unclear, and evidence of the possible effects of living at high altitudes on homicide rates is limited. This research aimed to investigate the mortality rates resulting from various types of aggression that culminated in homicides in Ecuador and to explore potential differences associated with altitude. Methods: An ecological analysis of homicide rates in Ecuador was conducted from 2001 to 2022. Homicide cases and the population at risk were categorized based on their place of residence according to two altitude classifications: a binary classification of low (<2,500 m) and high altitude (>2,500 m), and a detailed classification according to criteria by the International Society for Mountain Medicine, which includes low (<1,500 m), moderate (1,500-2,500 m), high (2,500-3,500 m), and very high altitude (3,500-5,500 m) categories. Both crude and directly age-sex standardized mortality rates were calculated for each altitude category. Results: We analyzed a total of 40,708 deaths attributed to aggressions (ICD-10 codes X85-Y09). The total homicide rate for men was 21.29 per 100,000 (95% confidence interval [CI]: 9.55-32.37), whereas for women, it was 2.46 per 100,000 (95% CI: 1.44-3.27). Average rates across the 22 analyzed years were higher at low altitudes (men: 13.2/100,000 and women: 1.33/100,000) as compared with high altitudes (men: 5.79/100,000 and women: 1.05/100,000). Notably, the male-to-female rate difference was more pronounced at low altitudes (898%) than at high altitudes (451%). Conclusions: Our study revealed a higher prevalence of homicides in certain provinces and significant disparities in mortality rates between men and women. Although we cannot establish a direct relationship between altitude and homicide rates, further research is needed to explore potential confounding factors and a better understanding of the underlying causes for these variations.

Different Patterns of Care and Survival Outcomes in Transplant-Centre Managed Patients with Early-Stage HCC: Real-World Data from an Australian Multi-Centre Cohort Study.

The management of early-stage hepatocellular carcinoma (HCC) is complex, with multiple treatment strategies available. There is a paucity of literature regarding variations in the patterns of care and outcomes between transplant and non-transplant centres. We conducted this real-world multi-centre cohort study in two liver cancer referral centres with an integrated liver transplant program and an additional eight non-transplant HCC referral centres across Australia to identify variation in patterns of care and key survival outcomes. Patients with stage Barcelona Clinic Liver Cancer (BCLC) 0/A HCC, first diagnosed between 1 January 2016 and 31 December 2020, who were managed at a participating site, were included in the study. Patients were excluded if they had a history of prior HCC or if they received upfront liver transplantation. A total of 887 patients were included in the study, with 433 patients managed at a liver cancer centre with a transplant program (LTC) and 454 patients managed at a non-transplant centre (NTC). Management at an LTC did not significantly predict allocation to resection (adjusted OR 0.75, 95% CI 0.50 to 1.11, p = 0.148). However, in those not receiving resection, LTC and NTC patients were systematically managed differently, with LTC patients five times less likely to receive upfront ablation than NTC patients (adjusted OR 0.19, 95% CI 0.13 to 0.28, p < 0.001), even after adjusting for tumour burden, as well as for age, gender, liver disease aetiology, liver disease severity, and medical comorbidities. LTCs exhibited significantly higher proportions of patients undergoing TACE for every tumour burden category, including those with a single tumour measuring 2 cm or less (p < 0.001). Using multivariable Cox proportional hazards analysis, management at a transplant centre was associated with reduced all-cause mortality (adjusted HR 0.71, 95% CI 0.51 to 0.98, p = 0.036), and competing-risk regression analysis, considering liver transplant as a competing event, demonstrated a similar reduction in risk (adjusted HR 0.70, 95% CI 0.50 to 0.99, p = 0.041), suggesting that the reduced risk of death is not fully explained by higher rates of transplantation. Our study highlights systematic differences in HCC care between large volume liver transplant centres and other sites, which has not previously been well-described. Further work is needed to better define the reasons for differences in treatment allocation and to aim to minimise unwarranted treatment variation to maximise patient outcomes across Australia.

Carbon stock quantification in a floodplain restoration chronosequence along a Mediterranean-montane riparian corridor.

Uncertainty in the global carbon (C) budget has been reduced for most stocks, though it remains incomplete by not considering aquatic and transitional zone carbon stocks. A key issue preventing such complete accounting is a lack of available C data within these aquatic and aquatic-terrestrial transitional ecosystems. Concurrently, quantifiable results produced by restoration practices that explicitly target C stock accumulation and sequestration remain inconsistent or undocumented. To support a more complete carbon budget and identify impacts on C stock accumulation from restoration treatment actions, we investigated C stock values in a Mediterranean-montane riparian floodplain system in California, USA. We quantified the C stock in aboveground biomass, large wood, and litter in addition to the C and total nitrogen in the upper soil profile (5 cm) across 23 unique restoration treatments and remnant old-growth forests. Treatments span 40 years of restoration actions along seven river kilometers of the Cosumnes River, and include process-based (limited intervention), assisted (horticultural planting and other intensive restoration activities), hybrid (a combination of process and assisted actions), and remnant (old-growth forests that were not created with restoration actions) sites. Total C values measured up to 1100 Mg ha-1 and averaged 129 Mg ha-1 with biomass contributing the most to individual plot measurements. From 2012 to 2020, biomass C stock measurements showed an average 32 Mg ha-1 increase across all treatments, though treatment specific values varied. While remnant forest plots held the highest average C values across all stocks (336 Mg ha-1), C values of different stocks varied across treatment type. Process-based restoration treatments held more average biomass C (120 Mg ha-1) than hybrid (23 Mg ha-1) or assisted restoration treatments (50 Mg ha-1), while assisted restoration treatments held more average total C in soil and litter (58 Mg ha-1) than hybrid (35 Mg ha-1) and process-based restoration treatments (37 Mg ha-1). Regardless of treatment type, time was a significant factor for all C stock values. These findings support a more inclusive global carbon budget and provide valuable insight into restoration treatment actions that support C stock accumulation.

Dimerization of assimilatory NADPH-dependent sulfite reductase reveals elements for diflavin reductase binding at a minimal interface.

Escherichia coli NADPH-dependent assimilatory sulfite reductase is responsible for fixing sulfur for incorporation into sulfur-containing biomolecules. The oxidoreductase is composed of two subunits, an NADPH, FMN, and FAD-binding diflavin reductase and an iron siroheme and Fe4S4-containing oxidase. How they interact has been an unknown for over 50 years because the complex is highly flexible, thus has been intransigent for traditional X-ray or cryo-EM structural analysis. Using a combination of the chameleon plunging system with a fluorinated lipid we overcame the challenge of preserving the minimal dimer between the subunits for high-resolution cryo-EM analysis. Here, we report the first structure of the complex between the reductase and oxidase, revealing how they interact in a minimal interface. Further, we determined the structural elements that discriminate between the pairing of a siroheme-containing oxidase with a diflavin reductase or a ferredoxin partner to channel the six electrons that reduce sulfite to sulfide.

Diving head-first into brain intravital microscopy.

Tissue microenvironments during physiology and pathology are highly complex, meaning dynamic cellular activities and their interactions cannot be accurately modelled ex vivo or in vitro. In particular, tissue-specific resident cells which may function and behave differently after isolation and the heterogenous vascular beds in various organs highlight the importance of observing such processes in real-time in vivo. This challenge gave rise to intravital microscopy (IVM), which was discovered over two centuries ago. From the very early techniques of low-optical resolution brightfield microscopy, limited to transparent tissues, IVM techniques have significantly evolved in recent years. Combined with improved animal surgical preparations, modern IVM technologies have achieved significantly higher speed of image acquisition and enhanced image resolution which allow for the visualisation of biological activities within a wider variety of tissue beds. These advancements have dramatically expanded our understanding in cell migration and function, especially in organs which are not easily accessible, such as the brain. In this review, we will discuss the application of rodent IVM in neurobiology in health and disease. In particular, we will outline the capability and limitations of emerging technologies, including photoacoustic, two- and three-photon imaging for brain IVM. In addition, we will discuss the use of these technologies in the context of neuroinflammation.

Mechanically induced localisation of SECONDARY WALL INTERACTING bZIP is associated with thigmomorphogenic and secondary cell wall gene expression.

Plant growth requires the integration of internal and external cues, perceived and transduced into a developmental programme of cell division, elongation and wall thickening. Mechanical forces contribute to this regulation, and thigmomorphogenesis typically includes reducing stem height, increasing stem diameter, and a canonical transcriptomic response. We present data on a bZIP transcription factor involved in this process in grasses. Brachypodium distachyon SECONDARY WALL INTERACTING bZIP (SWIZ) protein translocated into the nucleus following mechanostimulation. Classical touch-responsive genes were upregulated in B. distachyon roots following touch, including significant induction of the glycoside hydrolase 17 family, which may be unique to grass thigmomorphogenesis. SWIZ protein binding to an E-box variant in exons and introns was associated with immediate activation followed by repression of gene expression. SWIZ overexpression resulted in plants with reduced stem and root elongation. These data further define plant touch-responsive transcriptomics and physiology, offering insights into grass mechanotranduction dynamics.

Viral Conjunctivitis Rates Unchanged Before and During the COVID-19 Pandemic in an Ophthalmology Clinic.

Background: Millions of acute conjunctivitis cases occur in the United States annually. The impact of COVID-19 mitigation practices on viral conjunctivitis incidence within ophthalmology clinics has not been reported. We hypothesized that viral conjunctivitis rates would decrease with implementation of such practices. Methods: A retrospective chart review was conducted at a single academic center's ophthalmology clinics. Electronic health record data was queried using ICD-10 diagnostic codes to include 649 patients aged 2-97 with viral, bacterial, or allergic conjunctivitis diagnosed either before (6/1/2018-5/1/2019) or during (6/1/2020-5/1/2021) COVID-19 precautions. Conjunctivitis rates per ophthalmology clinic visit were compared using rate-ratio analysis. Logistic regression evaluated the effects of age, sex, and race among those with conjunctivitis. Results: A total of 66,027 ophthalmology clinic visits occurred during the study period. Viral conjunctivitis rates per visit did not significantly change after enacting COVID-19 mitigation strategies, but allergic conjunctivitis rates significantly increased (viral: RR 0.82, 95% CI 0.51 to 1.31, p=0.408; allergic: RR 1.70, 95% CI 1.43 to 2.03, p<0.001). When controlling for time, younger age (≤ median age 55) (p=0.005) and Caucasian race (p=0.009) were associated with higher viral conjunctivitis frequency. Conclusion: Contrary to trends reported in emergency departments, viral conjunctivitis rates within an ophthalmology clinic did not significantly change after COVID-19 mitigation strategies, though allergic conjunctivitis rates increased. Patients' avoidance of emergency departments during the pandemic may have contributed. Further investigation is required to explore variation in ophthalmology patient populations and needs based on care setting.

A retrospective review included 649 patients with viral, bacterial, or allergic conjunctivitis diagnosed at a single center's ophthalmology clinics before (6/1/2018­5/1/2019) or during (6/1/2020­5/1/2021) COVID-19 precautions. Contrary to emergency department experiences, viral conjunctivitis rates did not significantly change after COVID-19 precautions. However, allergic conjunctivitis rates significantly increased. Conjunctivitis presentation in ophthalmology clinics differed from that reported in emergency departments, warranting further evaluation of variation in patient needs by setting.

Changes in Fracture Shortening Occur in the First 2 Weeks Following Completely Displaced Adolescent Clavicle Fractures.

BACKGROUND: Shortening of midshaft clavicle fractures has been described as a critical fracture characteristic to guide treatment. The degree to which shortening may change in the initial weeks following injury has not been well studied. The purpose of this study was to evaluate the change in shortening of adolescent clavicle fractures in the first 2 weeks following injury. METHODS: This was a multicenter study of prospectively collected data, which was acquired as a part of a cohort study of adolescent clavicle fractures. A consecutive series of patients 10 to 18 years of age with completely displaced diaphyseal clavicle fractures with baseline radiographs 0 to 6 days from the date of injury, as well as 7 to 21 days from the date of injury, were included. Measurements of end-to-end (EES) and cortex-to-corresponding-cortex (CCS) shortening were performed. RESULTS: A total of 142 patients were included. Baseline radiographs were obtained at a mean of 1.0 day following injury with mean EES of 22.3 mm, and 69% of patients demonstrating >20 mm of shortening. Follow-up radiographs obtained at a mean of 13.8 days postinjury demonstrated a mean absolute change in EES of 5.4 mm. Forty-one percentage of patients had >5 mm of change in EES. When analyzing changes in shortening relative to the specific threshold of 20 mm, 18 patients (41%) with <20 mm EES increased to ≥20 mm EES, and 19 patients (19%) with ≥20 mm EES decreased to <20 mm EES at 2-week follow-up. CONCLUSIONS: Clinically significant changes in fracture shortening occurred in 41% of adolescents with completely displaced clavicle fractures in the first 2 weeks after injury. In 26% of patients, this resulted in a change from above or below the commonly used shortening threshold of 20 mm, potentially altering the treatment plan by many providers. There is no evidence to suggest that adolescent clavicle fracture shortening affects outcomes, and as such, the authors do not advocate for the use of this parameter to guide treatment. However, among physicians who continue to use this parameter to guide treatment, this study supports that repeat radiographic assessment 2 weeks postinjury may be a better measure of the true shortening of this common adolescent injury. LEVEL OF EVIDENCE: Level IV-case series.

Decellularized Descemet Membrane Anterior Keratoplasty With Allogeneic Simple Limbal Epithelial Transplantation for Partial Limbal Stem Cell Deficiency Following Partial Keratolimbal Allograft Failure.

PURPOSE: The purpose of this study was to describe the use of Descemet membrane anterior keratoplasty (DMAK) with modified allogeneic simple limbal epithelial transplantation to treat a case of partial limbal stem cell deficiency (LSCD) following keratolimbal allograft failure. METHODS: Case report. RESULTS: A 21-year-old woman with autoimmune polyglandular syndrome-related LSCD presented with pain and decreased vision. There was partial failure and recurrence of LSCD after a severe/acute keratolimbal allograft rejection that led to persistent epithelial defects refractory to conservative therapy. This was treated with a superficial keratectomy and placement of a DMAK. A modified allogeneic simple limbal epithelial transplantation was performed with an overlying amniotic membrane and temporary tarsorrhaphy. There was epithelialization of the corneal surface by 3 to 4 weeks with an improved ocular surface. Despite partial recurrence of late staining, the cornea has remained epithelized, vision has improved, and the patient has remained pain-free more than 1.5 years following the procedure. CONCLUSIONS: DMAK may be a long-term substrate to help improve and maintain epithelization of the cornea up to 1.5 years. DMAK may be a viable alternative to using amniotic membrane as a scaffold in allogeneic simple limbal epithelial transplantation for treatment of partial LSCD. While late epithelial staining recurred in our patient, DMAK appears to prevent recurrent epithelial defects and reduce ocular surface pain, conveying an improvement in quality of life in patients at high risk of rejection/failure.

Cilia-deficient renal tubule cells are primed for injury with mitochondrial defects and aberrant tryptophan metabolism.

The exocyst and Ift88 are necessary for primary ciliogenesis. Overexpression of Exoc5 (OE), a central exocyst component, resulted in longer cilia and enhanced injury recovery. Mitochondria are involved in acute kidney injury (AKI). To investigate cilia and mitochondria, basal respiration and mitochondrial maximal and spare respiratory capacity were measured in Exoc5 OE, Exoc5 knockdown (KD), Exoc5 ciliary targeting sequence mutant (CTS-mut), control Madin-Darby canine kidney (MDCK), Ift88 knockout (KO), and Ift88 rescue cells. In Exoc5 KD, Exoc5 CTS-mut, and Ift88 KO cells, these parameters were decreased. In Exoc5 OE and Ift88 rescue cells they were increased. Reactive oxygen species were higher in Exoc5 KD, Exoc5 CTS-mut, and Ift88 KO cells compared with Exoc5 OE, control, and Ift88 rescue cells. By electron microscopy, mitochondria appeared abnormal in Exoc5 KD, Exoc5 CTS-mut, and Ift88 KO cells. A metabolomics screen of control, Exoc5 KD, Exoc5 CTS-mut, Exoc5 OE, Ift88 KO, and Ift88 rescue cells showed a marked increase in tryptophan levels in Exoc5 CTS-mut (113-fold) and Exoc5 KD (58-fold) compared with control cells. A 21% increase was seen in Ift88 KO compared with rescue cells. In Exoc5 OE compared with control cells, tryptophan was decreased 59%. To determine the effects of ciliary loss on AKI, we generated proximal tubule-specific Exoc5 and Ift88 KO mice. These mice had loss of primary cilia, decreased mitochondrial ATP synthase, and increased tryptophan in proximal tubules with greater injury following ischemia-reperfusion. These data indicate that cilia-deficient renal tubule cells are primed for injury with mitochondrial defects in tryptophan metabolism.NEW & NOTEWORTHY Mitochondria are centrally involved in acute kidney injury (AKI). Here, we show that cilia-deficient renal tubule cells both in vitro in cell culture and in vivo in mice are primed for injury with mitochondrial defects and aberrant tryptophan metabolism. These data suggest therapeutic strategies such as enhancing ciliogenesis or improving mitochondrial function to protect patients at risk for AKI.

Hydroxychloroquine inhibits hemolysis-induced arterial thrombosis ex vivo and improves lung perfusion in hemin-treated mice.

BACKGROUND: Free labile hemin acts as a damage-associated molecular pattern during acute and chronic hemolysis and muscle injury, supporting platelet activation and thrombosis. OBJECTIVES: To investigate the anti-thrombotic potential of hydroxychloroquine on hemolysis-induced platelet activation and arterial thrombosis. METHODS: The effect of hydroxychloroquine on hemin-induced platelet activation and hemolysis-induced platelet recruitment and aggregation was measured in washed platelets and hemolyzed blood, respectively. Its effect on ferric-chloride (FeCl3)-induced arterial thrombosis and lung perfusion following hemin injection was assessed in wild-type mice. RESULTS: Erythrocyte lysis and endothelial cell activation cooperatively supported platelet aggregation and thrombosis at arterial shear stress. This thrombotic effect was reversed by hydroxychloroquine. In a purified system, hydroxychloroquine inhibited platelet build-up on immobilized von Willebrand factor in hemolyzed blood without altering initial platelet recruitment. Hydroxychloroquine inhibited hemin-induced platelet activation and phosphatidylserine exposure independently of reactive oxygen species generation. In the presence of hemin, hydroxychloroquine did not alter glycoprotein VI shedding but reduced C-type-lectin-like-2 expression on platelets. In vivo, hydroxychloroquine reversed pulmonary perfusion decline induced by exogenous administration of hemin. In arterial thrombosis models, hydroxychloroquine inhibited ferric-chloride-induced thrombosis in the carotid artery and reduced von Willebrand factor accumulation in the thrombi. CONCLUSION: Hydroxychloroquine inhibited hemolysis-induced arterial thrombosis ex vivo and improved pulmonary perfusion in hemin-treated mice, supporting a potential benefit of its use as an adjuvant therapy in hemolytic diseases to limit arterial thrombosis and to improve organ perfusion.

Isokinetic Shoulder Strength and its Associations to Injury in Tactical Populations: A Critical Review.

The aim of this review is to evaluate existing isokinetic testing protocols for the shoulder in tactical occupations, document their shoulder strength profiles, and determine any associations to shoulder injury. Four electronic databases were searched (Medline/Pubmed, Ovid/Emcare, CINAHL/Ebsco and Embase) using the keywords police OR law enforcement, firefighter, military, AND isokinetic. Articles were eligible if they had at least one cohort of a tactical population and included isokinetic testing of the glenohumeral joint. The search yielded 275 articles. After screening for duplicates and inclusion criteria, 19 articles remained for review, six of which assessed injury correlation. 17 articles evaluated military personnel and two examined firefighters. Articles were categorized by study design, population, isokinetic protocols, strength outcome measures and statistical measures. Concentric internal rotation (IR) and external rotation (ER) strength at 60 degrees/second were reported most frequently (84% of cases). There was a paucity of testing speeds, repetition ranges and contraction types evaluated when compared to existing literature in other populations with high shoulder injury occurrence such as overhead and collision athletes. Outside of military cohorts, there is limited data available to characterise the isokinetic strength profile of the shoulder in tactical occupations. Meta-analysis for injury association was unable to be performed due to independent variable and statistical heterogeneity. However, a best evidence synthesis suggested conflicting evidence to support the association of injury with isokinetic strength testing in tactical populations. Future studies should prioritise prospective designs utilising variable speeds, repetition schemes and contraction types to better capture the dynamic occupational demands in tactical groups.