Astrobiological Potential of Venus Atmosphere Chemical Anomalies and Other Unexplained Cloud Properties.

Long-standing unexplained Venus atmosphere observations and chemical anomalies point to unknown chemistry but also leave room for the possibility of life. The unexplained observations include several gases out of thermodynamic equilibrium (e.g., tens of ppm O2, the possible presence of PH3 and NH3, SO2 and H2O vertical abundance profiles), an unknown composition of large, lower cloud particles, and the "unknown absorber(s)." Here we first review relevant properties of the venusian atmosphere and then describe the atmospheric chemical anomalies and how they motivate future astrobiology missions to Venus.

A clinical and electrophysiological case study of a child with a novel frame shift mutation in the CACNA1F and missense variation of RIMS1 genes.

PURPOSE: The purpose of this paper is to present a case study illustrating the importance of electrophysiological investigation in the diagnosis and serial monitoring of isolated congenital nystagmus. RESULTS: Serial electophysiological monitoring was undertaken in the male proband over a 9-year period commencing with initial assessment at 12 weeks of age: Skin electroretinograms (sERGs) were initially absent but subsequently revealed low-amplitude responses, electronegative morphologies and notched flicker responses suggestive of incomplete congenital stationary night blindness (CSNB2), but with an absent dark-adapted rod-specific response, while flash visual evoked potentials (fVEPs) demonstrated persistent crossed asymmetry, typical of albinoid misrouting of the optic nerves. Molecular investigation confirmed a novel hemizygous frame shift mutation in the CACNA1F gene, considered to be pathogenic and causative of X-linked CSNB2; additionally, a novel heterozygous missense variation in one copy of the RIMS1 gene was identified, pathogenic mutations of which underpin late-onset autosomal dominant cone-rod dystrophy (type 7). Segregation studies confirmed maternal inheritance of both mutations in the clinically asymptomatic mother in whom depressed rod-specific responses were confirmed on sERG. The child's visual acuity has remained stable as have the sERGs which have been verified by recordings using scleral electrodes. CONCLUSIONS: The importance of recording ERGs as part of evaluating infants who present with nystagmus, even with a normal fundus appearance, is supported. Further, sERGs were able to distinguish an apparent variant of CSNB2 and could give consistent results over many years. FVEP results add to the evidence that albinoid misrouting of the optic nerves may occur in cases of CSNB2. ERGs and fVEPs can provide valuable information in discriminating the relative diagnostic importance of multiple genetic abnormalities.

Hawai'i Rural Health Program: Shaping the Next Generation of Rural Doctors.

Like many areas of the United States, Hawai'i and its rural communities are suffering from a significant physician shortage. The University of Hawai'i (UH) John A. Burns School of Medicine (JABSOM) developed the Hawai'i Rural Health Program (HRHP) in 2011 to help provide early and substantial rural training experiences for its medical students in hopes of generating more rural health care providers. Thus far, 20.6% of the students who participated in this program and have since graduated from residency are now practicing in rural communities. Final exam grades of students who participated in the program were not statistically different from those who did not participate, suggesting a similar quality of training between both the rural and traditional cohorts of students. Reflections from students who completed the program demonstrate the large and lasting impact that this immersive experience has on their medical education and desire to help rural communities.

Open-Label Pilot Study of Interferon Gamma-1b in Patients With Non-Infantile Osteopetrosis.

The only treatment currently available for patients with severe infantile osteopetrosis is hematopoietic cell transplantation (HCT). HCT-related toxicity and mortality risks typically preclude its use in non-infantile patients, and other therapies are needed for these patients who have significant disease-related morbidity. Interferon gamma-1b is currently approved by the U.S. Food and Drug Administration (FDA) for treatment of severe infantile osteopetrosis (autosomal recessive osteopetrosis [ARO]). However, little is known about the effects of interferon gamma-1b in non-infantile osteopetrosis. Thus, this pilot study aimed at testing the safety and tolerability of interferon gamma-1b in patients with non-infantile osteopetrosis and assessing the clinical effects. We performed a 12-month, open-label, multi-center pilot study involving patients >1 year-old diagnosed radiographically with osteopetrosis. Patients were initiated on interferon gamma-1b subcutaneously 15 µg/m2 three times weekly, to be titrated over 3 weeks to a goal of 100 µg/m2 three times weekly. The primary aim was safety and tolerability. The secondary aims were to assess changes in peripheral quantitative computed tomography (pQCT), dual-energy x-ray absorptiometry (DXA) bone mineral density (BMD) Z-scores, bone biomarkers, and quality-of-life (QOL) measures. Four of the five participants enrolled withdrew from the study between 3 and 9 months due to intolerability of interferon gamma-1b-related flu-like symptoms. The last participant completed the study with the addition of prednisone on days of interferon gamma-1b administration. DXA and pQCT outcomes were stable over 6-12 months, and there were no clear trends in bone biomarkers or QOL measures. No serious drug-related adverse events were reported during this study. Interferon gamma-1b was only tolerable in one of five participants with the addition of prednisone. The stabilization of BMD and other measures of bone health during this study suggest possible positive effects of interferon gamma-1b on osteopetrosis; however, additional data are needed before conclusions on treatment efficacy can be made. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Transitioning from cerebrospinal fluid to blood tests to facilitate diagnosis and disease monitoring in Alzheimer's disease.

Alzheimer's disease (AD) is increasingly prevalent worldwide, and disease-modifying treatments may soon be at hand; hence, now, more than ever, there is a need to develop techniques that allow earlier and more secure diagnosis. Current biomarker-based guidelines for AD diagnosis, which have replaced the historical symptom-based guidelines, rely heavily on neuroimaging and cerebrospinal fluid (CSF) sampling. While these have greatly improved the diagnostic accuracy of AD pathophysiology, they are less practical for application in primary care, population-based and epidemiological settings, or where resources are limited. In contrast, blood is a more accessible and cost-effective source of biomarkers in AD. In this review paper, using the recently proposed amyloid, tau and neurodegeneration [AT(N)] criteria as a framework towards a biological definition of AD, we discuss recent advances in biofluid-based biomarkers, with a particular emphasis on those with potential to be translated into blood-based biomarkers. We provide an overview of the research conducted both in CSF and in blood to draw conclusions on biomarkers that show promise. Given the evidence collated in this review, plasma neurofilament light chain (N) and phosphorylated tau (p-tau; T) show particular potential for translation into clinical practice. However, p-tau requires more comparisons to be conducted between its various epitopes before conclusions can be made as to which one most robustly differentiates AD from non-AD dementias. Plasma amyloid beta (A) would prove invaluable as an early screening modality, but it requires very precise tests and robust pre-analytical protocols.

Characterizing Immune-Mediated Cytopenias After Allogeneic Hematopoietic Cell Transplantation for Pediatric Nonmalignant Disorders.

Immune-mediated cytopenias (IMC)-isolated or combined hemolytic anemia, thrombocytopenia, or neutropenia-are increasingly recognized as serious complications after allogeneic hematopoietic cell transplantation (HCT) for nonmalignant disorders (NMD). However, IMC incidence, duration, response to therapy, and risk factors are not well defined. This retrospective chart review identified cases of IMC with serologic confirmation among patients who underwent HCT for NMD at a single institution between 2010 and 2017. IMC after HCT for NMD in a large pediatric cohort (n = 271) was common with a cumulative incidence of 18%, identified at a median of 136 days after HCT. Treatment included prolonged immune suppression (>3 months) in 58% of all IMC cases, 91% when multiple cell lines were affected. Multiple therapeutic agents were used for the majority affected, and median time to resolution of IMC was 118 days from diagnosis. Fine-Gray competing risk multivariate regression analysis identified a combined risk factor of younger age (<3 years) and inherited metabolic disorder, as well as hemoglobinopathy (at any age) associated with 1-year incidence of IMC (P < .01). We expand these findings with the observation of declining donor T-lymphoid chimerism from day 60 to 100 and lower absolute CD4+ counts at day 100 (P < .01), before median onset of IMC, for patients with IMC compared to those without. In this cohort, 4 deaths (8%) were associated with IMC, including 2 requiring second transplantation for secondary graft failure. Although the pathogenesis of IMC post-HCT for NMD remains elusive, further research may identify approaches to prevent and better treat this HCT complication.

Outcome After Cord Blood Transplantation Using Busulfan Pharmacokinetics-Targeted Myeloablative Conditioning for Hurler Syndrome.

We report the outcomes of cord blood transplantation (CBT) with a busulfan (Bu) pharmacokinetics-targeted myeloablative conditioning regimen in 97 children with Hurler syndrome (HS) performed between 2004 and 2016. The median age at CBT was 10.8 months (range, 0.23 to 63.2 months). The median duration of follow-up for surviving patients was 4.2 years (range, 1.0 to 12.8 years). Five-year overall survival (OS) and engrafted survival (ES) were 88% and 79%, respectively. OS was 95% in patients who received Bu/fludarabine (Flu)/antithymocyte globulin (ATG) conditioning, 90% in those who received Bu/cyclophosphamide (Cy)/ATG, and 74% in those who received Bu/Cy/alemtuzumab (P = .02). ES was 84% for recipients of Bu/Flu/ATG conditioning, 83% for recipients of Bu/Cy/ATG conditioning, and 65% for recipients of Bu/Cy/alemtuzumab conditioning (P = .34). Receipt of washed CB units (P = .03) and HLA matching ≤6/10 (P = .02) were associated with significantly lower ES. The 1-year cumulative incidence of graft failure was 11% (95% confidence interval, 6% to 21%). Five patients (5%) had grade III-IV acute GVHD, 5 patients had limited chronic GVHD, and 1 patient had extensive GVHD. The incidence of veno-occlusive disease was higher in patients conditioned with Bu/Cy compared with those conditioned with Bu/Flu (19% [n = 10] versus 5% [n = 2]: P = .03). Of the 11 patients with graft failure, 8 (73%) were aplastic, and 3 (27%) had autologous reconstitution. Of 11 patients with graft failure, 9 underwent a second CBT, and 8 (89%) survived. Full donor chimerism was observed in 89% patients after first CBT and in all patients after second CBT. Survival after CBT for HS has improved, but better strategies are still needed to improve graft outcomes.

Neurocognitive benchmarks following transplant for emerging cerebral adrenoleukodystrophy.

OBJECTIVE: To quantify benchmark treatment outcomes that may be enabled by newborn screening surveillance for X-linked adrenoleukodystrophy (ALD), we report neurocognitive, neuropsychiatric, and MRI change for boys who underwent hematopoietic stem cell transplant (HSCT) at initial stages of demyelination, prior to neurocognitive signs of disease. METHODS: Retrospective chart review identified 36 patients whose cerebral ALD was detected and treated early, with lesion severity less than 5 on the ALD-specific MRI scoring system. Median age at transplant was 7.3 years (range, 4.0-16.1). Progression of radiologic disease on MRI in the 2 years following HSCT was examined relative to the severity of the initial lesion for 33 patients, and longitudinal neurocognitive and neuropsychiatric outcomes were studied for 30 patients. RESULTS: Patients whose pretransplant lesion extended beyond the splenium of the corpus callosum and adjacent periventricular white matter (MRI severity score >2) demonstrated lower posttransplant neurocognitive scores, more neuropsychiatric symptoms, and more disease progression on MRI than patients with a less severe lesion. Changes from baseline neurocognitive functioning were greater at 2 years posttransplant as compared to 1 year. There was greater variance and risk of lesion progression as pretransplant MRI severity increased. CONCLUSION: To realize the full benefits of newborn screening, clinicians must detect very small demyelinating lesions during surveillance and intervene quickly. Novel interventions that reduce risks inherent in allogeneic transplantation are needed. Trial endpoints should include direct neurocognitive assessment and extend at least 2 years posttreatment to provide the greatest sensitivity to detect neurocognitive morbidity.

Early-Stage Diabetic Neuropathy Reduces Foot Strength and Intrinsic but Not Extrinsic Foot Muscle Size.

BACKGROUND: Tracking progression of diabetic peripheral polyneuropathy (DPN) is usually focused on sensory nerves and subjective testing methods. Recent studies have suggested that distal muscle atrophy may precede sensation loss. Methods to objectively measure distal muscle size and strength are needed to help understand how neuropathy affects muscle function. PURPOSE: To evaluate individual intrinsic and extrinsic foot muscle sizes and functional foot strength in participants with DPN. METHODS: Thirty individuals participated in this cross-sectional study (15 DPN and 15 matched controls). Sizes of 10 separate muscles of the lower leg and foot were measured using ultrasound imaging. Functional foot strength was also quantified using custom great toe and lateral toe flexion tests along with a doming test. Muscle size and strength metrics were compared between groups using ANOVAs and paired t-tests (α = 0.05). Correlations between strength and relevant muscle sizes were also evaluated. RESULTS: The sizes of all four intrinsic foot muscles were smaller in individuals with DPN (p ≤ 0.03), while only one (toe extensor) of the six extrinsic muscles was smaller (p ≤ 0.03), while only one (toe extensor) of the six extrinsic muscles was smaller (p ≤ 0.03), while only one (toe extensor) of the six extrinsic muscles was smaller (p ≤ 0.03), while only one (toe extensor) of the six extrinsic muscles was smaller (r ≤ 0.80) with several corresponding intrinsic muscle sizes. The doming strength test did not show any difference between groups and was moderately correlated with one muscle size (r ≤ 0.80) with several corresponding intrinsic muscle sizes. The doming strength test did not show any difference between groups and was moderately correlated with one muscle size (. CONCLUSION: Diabetic peripheral polyneuropathy affects intrinsic muscles before extrinsics. Ultrasound imaging of individual muscles and functional toe flexion tests can be used clinically to monitor DPN progression and foot function. Participants need to be trained in the doming test before a relationship can be established between this test and DPN foot function. Future studies should include muscle quality measurements to better understand characteristics of affected muscles.

Failure of intrathecal allogeneic mesenchymal stem cells to halt progressive demyelination in two boys with cerebral adrenoleukodystrophy.

Cerebral adrenoleukodystrophy is an inflammatory demyelinating condition that is the result of a mutation in the X-linked ABCD1 gene, a peroxisomal very long chain fatty acid transporter. Although mutations in this gene result in adrenal insufficiency in the majority of affected individuals, 40% of those affected develop the demyelinating cerebral form, cerebral adrenoleukodystrophy (CALD). CALD is characterized by imaging findings of demyelination and contrast enhancement on magnetic resonance imaging (MRI). Although allogeneic hematopoietic cell transplantation can arrest progression of CALD early in its course, there is no accepted therapy for patients with advanced CALD. Mesenchymal stem cells (MSCs) have been used in a variety of clinical trials to capitalize on their anti-inflammatory properties as well as promote tissue repair. We delivered MSCs via intrathecal (IT) route to two boys with rapidly advancing CALD. The first boy received three doses 1 week apart, whereas the second boy received a single dose of IT MSCs. We note delivery of IT MSCs was feasible and without complication. Follow-up MRI scans after IT MSC delivery showed progressive demyelination in the first patient and no change in demyelination or contrast enhancement in the second patient. Although the infusion of IT MSCs was safe, it did not halt CALD progression in this setting, and future studies should focus on patient selection and dose optimization.

Clinical trial of laronidase in Hurler syndrome after hematopoietic cell transplantation.

BACKGROUND: Mucopolysaccharidosis I (MPS IH) is a lysosomal storage disease treated with hematopoietic cell transplantation (HCT) because it stabilizes cognitive deterioration, but is insufficient to alleviate all somatic manifestations. Intravenous laronidase improves somatic burden in attenuated MPS I. It is unknown whether laronidase can improve somatic disease following HCT in MPS IH. The objective of this study was to evaluate the effects of laronidase on somatic outcomes of patients with MPS IH previously treated with HCT. METHODS: This 2-year open-label pilot study of laronidase included ten patients (age 5-13 years) who were at least 2 years post-HCT and donor engrafted. Outcomes were assessed semi-annually and compared to historic controls. RESULTS: The two youngest participants had a statistically significant improvement in growth compared to controls. Development of persistent high-titer anti-drug antibodies (ADA) was associated with poorer 6-min walk test (6MWT) performance; when patients with high ADA titers were excluded, there was a significant improvement in the 6MWT in the remaining seven patients. CONCLUSIONS: Laronidase seemed to improve growth in participants <8 years old, and 6MWT performance in participants without ADA. Given the small number of patients treated in this pilot study, additional study is needed before definitive conclusions can be made.

Reduced-Toxicity (BuFlu) Conditioning Is Better Tolerated but Has a Higher Second Transplantation Rate Compared to Myeloablative Conditioning (BuCy) in Children with Inherited Metabolic Disorders.

Hematopoietic stem cell transplantation (HCT) is a primary treatment for various inherited metabolic disorders (IMDs). Achieving stable and sustained engraftment while minimizing transplantation-related morbidity and mortality is critical to optimizing outcomes for IMDs. Traditional regimens have used myeloablative approaches, primarily busulfan and cyclophosphamide (BuCy), which is associated with significant regimen-related toxicity. Alternatively, reduced-toxicity regimens, such as busulfan and fludarabine (BuFlu), have been proposed to offer similar efficacy with reduced toxicities. We compared transplantation-related outcomes with BuCy-based and BuFlu-based conditioning in patients with IMDs. We retrospectively analyzed the University of Minnesota's transplantation database for patients with IMDs who underwent HCT using a BuCy (with alemtuzumab) or BuFlu (with antithymocyte globulin) preparative regimen between March 2008 and September 2017. Overall survival (OS), event-free survival (EFS), and incidence of neutrophil and platelet recovery were determined using standard definitions. Complications such as graft failure, sinusoidal obstruction syndrome, hemorrhagic cystitis, and respiratory failure were compared. Graft failure includes primary and secondary aplastic graft failure with and without autologous recovery. The incidence of viral infections post-transplantation in the 2 regimens was also determined. A total of 99 patients underwent HCT for IMDs during the study period. Sixty-four patients received BuCy conditioning, and the other 35 received BuFlu. Hurler syndrome (46%) and adrenoleukodystrophy (43%) were the most common IMDs, and umbilical cord blood was the most common graft source (74%). One-year OS was similar in the 2 groups (81.2% in BuCy versus 85.5% in BuFlu; P = .8), with an EFS of 75% versus 63%, respectively. The 2 groups also had similar incidences of grade III-IV acute GVHD (9% versus 6%; P = .5) and chronic GVHD (9% versus 7%; P = .67). Neutrophil and platelet recovery were similar in the 2 groups, with a significantly shorter duration of hospital stay noted in the BuFlu cohort (median, 21 days versus 34 days; P = .002). The cumulative incidence of graft failure was significantly higher in the BuFlu group (29% versus 14%; P = .08), as was the rate of second HCT (27% versus 3%; P = .001). The incidences of adenoviral infection (14% versus 0%; P = .02) and hemorrhagic cystitis (23% versus 3%; P = .01) were higher in the BuCy group. T cell engraftment occurred significantly sooner with BuCy conditioning until 1-year post-transplantation, but donor myeloid engraftment was similar in the 2 groups. Our data indicate that reduced-toxicity conditioning is associated with lower rates of infection and other transplantation-related complications but is concerning for a higher rate of graft failure in patients with IMDs. Alternate immunosuppressive agents and novel techniques should be considered to minimize toxicities and reduce complications.

Post-transplant laronidase augmentation for children with Hurler syndrome: biochemical outcomes.

Allogeneic hematopoietic cell transplantation (HCT) benefits children with Hurler syndrome (MPS-IH). However, survivors remain burdened by substantial MPS-IH related residual disease. We studied the feasibility, safety and biochemical impact of augmentative recombinant intravenous enzyme replacement therapy (IV-ERT) post transplantation. Ten children with MPS-IH and ≥2 years from successful HCT underwent IV-ERT for 2 years' duration. Patients were monitored for anti-drug antibody (ADA) development, including inhibitory capacity and changes in urinary excretion of glycosaminoglycans (uGAG). Three patients demonstrated low-level ADA at baseline, though all children tolerated IV-ERT well. Eight patients developed ADA over the 2-year study, with 3 (38%) meeting criteria for an inhibitory ADA response. The aggregate cohort experienced a reduction in uGAG from baseline to study end, which was enhanced in children with low or no ADA response. Conversely, children with inhibitory ADA showed increase in uGAG over time. IV-ERT in previously transplanted children with MPS-IH appears safe and can reduce uGAG, although this is reversed by the presence of inhibitory ADA. These data show a biochemical change after initiation of post-HCT IV-ERT, but the occurrence of ADA and inhibitory antibodies are a concern and should be monitored in future efficacy trials. This trial was registered at www.clinicaltrials.gov , NCT01173016, 07/30/2010.

Biochemical and clinical response after umbilical cord blood transplant in a boy with early childhood-onset beta-mannosidosis.

BACKGROUND: Deficiency in the enzyme ß-mannosidase was described over three decades ago. Although rare in occurrence, the presentation of childhood-onset ß-mannosidase deficiency consists of hypotonia in the newborn period followed by global development delay, behavior problems, and intellectual disability. No effective pharmacologic treatments have been available. METHODS: We report 2-year outcomes following the first umbilical cord blood transplant in a 4-year-old boy with early childhood-onset disease. RESULTS: We show restoration of leukocyte ß-mannosidase activity which remained normal at 2 years posttransplant, and a simultaneous increase in plasma ß-mannosidase activity and dramatic decrease in urine-free oligosaccharides were also observed. MRI of the brain remained stable. Neurocognitive evaluation revealed test point gains, although the magnitude of improvement was less than expected for age, causing lower IQ scores that represent a wider developmental gap between the patient and unaffected peers. CONCLUSION: Our findings suggest that hematopoietic cell transplant can correct the biochemical defect in ß-mannosidosis, although preservation of the neurocognitive trajectory may be a challenge.

Association between APOE4 and biomarkers in cerebral adrenoleukodystrophy.

Cerebral adrenoleukodystrophy (cALD) is an inflammatory neurodegenerative disease associated with mutation of the ABCD1 gene. Proteomic analysis of cerebral spinal fluid (CSF) from young males with active cALD revealed markers of inflammation including APOE4. APOE4 genotype has been associated with an inferior prognosis following acute and chronic neurologic injury. We assessed APOE4 inheritance among 83 consecutive young males with cALD prior to hematopoietic cell transplant and its association with markers of cerebral disease. The allele frequency of APOE4 was not significantly different from that of the general population at 17%. Young males with cALD that were APOE4 carriers had similar CSF protein and chitotriosidase activity to that of non-carriers. In contrast, APOE4 carriers had an increased burden of cerebral disease involvement as determined by MRI severity score (10.5 vs 7.0 points, p = 0.01), higher gadolinium intensity score (2.0 vs 1.3 points, p = 0.007), inferior neurologic function (neurologic function score 2.4 vs 1.0, p = 0.001), and elevated CSF MMP2 levels compared to that of non-carriers (13168 vs 9472 pg/mL, p = 0.01). These are the first data showing that APOE4 is associated with increased severity of cerebral disease in cALD and suggest it may be a modifier of disease.

Intrathecal enzyme replacement for Hurler syndrome: biomarker association with neurocognitive outcomes.

PURPOSE: Abnormalities in cerebrospinal fluid (CSF) have been reported in Hurler syndrome, a fatal neurodegenerative lysosomal disorder. While no biomarker has predicted neurocognitive response to treatment, one of these abnormalities, glycosaminoglycan nonreducing ends (NREs), holds promise to monitor therapeutic efficacy. A trial of intrathecal enzyme replacement therapy (ERT) added to standard treatment enabled tracking of CSF abnormalities, including NREs. We evaluated safety, biomarker response, and neurocognitive correlates of change. METHODS: In addition to intravenous ERT and hematopoietic cell transplantation, patients (N = 24) received intrathecal ERT at four peritransplant time points; CSF was evaluated at each point. Neurocognitive functioning was quantified at baseline, 1 year, and 2 years posttransplant. Changes in CSF biomarkers and neurocognitive function were evaluated for an association. RESULTS: Over treatment, there were significant decreases in CSF opening pressure, biomarkers of disease activity, and markers of inflammation. Percent decrease in NRE from pretreatment to final intrathecal dose posttransplant was positively associated with percent change in neurocognitive score from pretreatment to 2 years posttransplant. CONCLUSION: Intrathecal ERT was safe and, in combination with standard treatment, was associated with reductions in CSF abnormalities. Critically, we report evidence of a link between a biomarker treatment response and neurocognitive outcome in Hurler syndrome.

Successful donor engraftment and repair of the blood-brain barrier in cerebral adrenoleukodystrophy.

Adrenoleukodystrophy (ALD) is caused by mutations within the X-linked ABCD1 gene, resulting in the inability to transport acylated very long chain fatty acids (VLCFAs) into the peroxisome for degradation. VLCFAs subsequently accumulate in tissues, including the central nervous system. Up to 40% of boys develop a severe progressive demyelinating form of ALD, cerebral ALD, resulting in regions of demyelination observed on brain magnetic resonance imaging that are associated with a "garland ring" of gadolinium contrast enhancement. Gadolinium enhancement indicates blood-brain barrier (BBB) disruption and an active inflammatory disease process. Only hematopoietic cell transplant (HCT) has been shown to halt neurologic progression, although the mechanism of disease arrest is unknown. We evaluated imaging- and transplant-related biomarkers in 66 males who underwent HCT. In 77% of patients, gadolinium contrast resolved by 60 days post-HCT. We determined that time to neutrophil recovery and extent of donor chimerism correlated significantly with time to contrast resolution post-HCT. Graft failure was associated with a significantly slower rate of contrast resolution (P < .0001). Time to neutrophil recovery remained significant in multivariate analysis with other biomarkers (P = .03). Our data suggest that robust donor myeloid recovery is necessary for timely repair of the BBB.

Modelling intestinal glucose absorption in premature infants using continuous glucose monitoring data.

BACKGROUND: Model-based glycaemic control protocols have shown promise in neonatal intensive care units (NICUs) for reducing both hyperglycaemia and insulin-therapy driven hypoglycaemia. However, current models for the appearance of glucose from enteral feeding are based on values from adult intensive care cohorts. This study aims to determine enteral glucose appearance model parameters more reflective of premature infant physiology. METHODS: Peaks in CGM data associated with enteral milk feeds in preterm and term infants are used to fit a two compartment gut model. The first compartment describes glucose in the stomach, and the half life of gastric emptying is estimated as 20 min from literature. The second compartment describes glucose in the small intestine, and absorption of glucose into the blood is fit to CGM data. Two infant cohorts from two NICUs are used, and results are compared to appearances derived from data in highly controlled studies in literature. RESULTS: The average half life across all infants for glucose absorption from the gut to the blood was 50 min. This result was slightly slower than, but of similar magnitude to, results derived from literature. No trends were found with gestational or postnatal age. Breast milk fed infants were found to have a higher absorption constant than formula fed infants, a result which may reflect known differences in gastric emptying for different feed types. CONCLUSIONS: This paper presents a methodology for estimation of glucose appearance due to enteral feeding, and model parameters suitable for a NICU model-based glycaemic control context.

Post-transplant adaptive function in childhood cerebral adrenoleukodystrophy.

Objective: Hematopoietic stem cell transplantation (HSCT) is the only treatment known to slow or halt inflammatory demyelination among boys with the cerebral form of X-linked adrenoleukodystrophy (cALD), a devastating childhood condition affecting the central nervous system. HSCT can lead to a range of adverse outcomes including fatality. Previous studies have examined the potential predictors of post-HSCT survival and neurologic functioning. However, little is known about patients' daily-life adaptive functional outcomes (i.e., ability to communicate, maintain social relationships, and independently execute tasks of daily living). The purpose of this retrospective cohort study was to identify which patient characteristics and treatment-related variables predict long-term adaptive function among the survivors of HSCT for cALD. Methods: We obtained caregiver ratings of adaptive functioning of 65 transplant survivors at an average of 4.6 years (range: 1.0-24.1 years) post-HSCT. Using linear regression with penalized maximum likelihood estimation, we modeled the relative contribution of pre-transplant neurocognitive test performance, MRI severity, transplant regimen, and length of time since transplant on patient adaptive functioning outcomes. Results: Higher radiographic disease severity and poorer performance on baseline neurocognitive tests requiring fine motor skills and visual perception were associated with inferior adaptive functioning after HSCT. Use of radiation during the transplant preparative regimen also predicted poorer adaptive outcomes. Interpretation: In addition to radiological disease severity, baseline neurocognitive test performance is associated with post-transplant adaptive functional outcomes. Neurocognitive measures may play an important role in prognostic counseling and post-transplant treatment planning for patients considering HSCT for cALD.