Case Study of Severe Accidental Hypothermia with Rapid Cooling, Preserved Shivering, and Consciousness with a Summary of Similar Case Reports.

We describe a case of severe accidental hypothermia of a kayaker with preserved consciousness and shivering despite a rectal temperature of 22.9°C following a 50-min immersion in 3°C water with an estimated core temperature cooling rate of 10.6°C/h. Based on survival at sea prediction curves and cooling rates from physiology studies, cold water (eg, 0-5°C) immersion is expected to drop core temperature by 2 to 4°C/h. Furthermore, accidental hypothermia classification systems predict that severely hypothermic patients are usually unconscious and not shivering. The patient in this report rewarmed rapidly at 3.6°C/h with only minimally invasive measures and was discharged fully neurologically intact. In 41 similar cases of survival in moderate to severe hypothermia with core temperatures <32°C due to cold water immersion, cold air exposure, or avalanche burial, mean cooling rates were 4.3±3.3°C/h (range 0.4-10.6°C/h). Including the current patient, shivering was reported in only four cases. We found several other cases of rewarming from moderate to severe hypothermia with only minimally invasive measures. The current and summarized cases lead us to conclude that patients may be at risk of severe hypothermia in <60 min of cold water immersion and that it is possible for severely hypothermic patients to have preserved consciousness, close to normal vital signs, and shivering. Minimally invasive or noninvasive rewarming of patients with severe hypothermia is also possible, especially in those who continue to shiver. Hypothermia management should not necessarily be guided by classification systems or core temperature alone but rather by a careful consideration of the entire clinical picture.

Evaluation of Self-collected Saliva Samples Without Viral Transport Media for SARS-CoV-2 Testing via RT-PCR and Comparison of Amplicon Sequences Against Commonly Used Primers in Diagnostic Assays.

INTRODUCTION: Mass screening for SARS-CoV-2 using nasopharyngeal swabs (NPS) is costly, uncomfortable for patients, and increases the chance of virus exposure to health care workers. Therefore, this study focused on determining if self-collected unpreserved saliva can be an effective alternative to NPS collection in COVID-19 surveillance. MATERIALS AND METHODS: In this study, patients being tested for SARS-CoV-2 using NPS were asked to provide a saliva sample to compare their results. NPS samples were evaluated for SARS-CoV-2 using BioFire® FilmArray® Torch® or Cepheid® GeneXpert® systems while saliva samples were evaluated using an in-house developed reverse transcriptase polymerase chain reaction (RT-PCR) which targeted the Envelope (E) and Nucleocapsid (N) genes. RESULTS: Detection of SARS-CoV-2 using self-collected saliva was found to be only slightly less accurate (<5%) than testing using NPS. In addition, initial saliva RT-PCR identified 27 positive subjects, 18 of which provided amplicons sufficient for confirmatory sequencing. The sequencing data showed a genetic shift in the virus within our population sometime between 22 June and July 8, 2021 from Alpha to Delta variant. CONCLUSIONS: The saliva sample collection method identifies the E gene in SARS COVID-2 samples which provides an alternative specimen source to the NPS. This identifies the S gene and ORF1ab. Saliva collection is more convenient to the patient, yields comparable results to NPS collection, and potentially increases Covid-19 surveillance.

Selective host autophagy is induced during the intracellular parasite Toxoplasma gondii infection controlling amino acid levels.

Toxoplasma gondii, a widespread parasite, has the ability to infect nearly any nucleated cell in warm-blooded vertebrates. It is estimated that around 2 billion people globally have been infected by this pathogen. Although most healthy individuals can effectively control parasite replication, certain parasites may evade the immune response, establishing cysts in the brain that are refractory to the immune system and resistant to available drugs. For its chronic persistence in the brain, the parasite relies on host cells' nutrients, particularly amino acids and lipids. Therefore, understanding how latent parasites persist in the brain is crucial for identifying potential drug targets against chronic forms. While shielded within parasitophorous vacuoles (PVs) or cysts, Toxoplasma exploits the host endoplasmic reticulum (ER) metabolism to sustain its persistence in the brain, resulting in host neurological alterations. In this study, we demonstrate that T. gondii disrupts the host ER homeostasis, resulting in the accumulation of unfolded protein within the host ER. The host counters this stress by initiating an autophagic pathway known as ER-phagy, which breaks down unfolded proteins into amino acids, promoting their recycling. Our findings unveil the underlying mechanisms employed by T. gondii to exploit host ER and lysosomal pathways, enhancing nutrient levels during infection. These insights provide new strategies for the treatment of toxoplasmosis. IMPORTANCE: Intracellular parasites employ several mechanisms to manipulate the cellular environment, enabling them to persist in the host. Toxoplasma gondii, a single-celled parasite, possesses the ability to infect virtually any nucleated cell of warm-blooded vertebrates, including nearly 2 billion people worldwide. Unfortunately, existing treatments and immune responses are not entirely effective in eliminating the chronic persisting forms of the parasite. This study reveals that T. gondii induces the host's autophagic pathway to boost amino acid levels in infected cells. The depletion of amino acids, in turn, influences the persistence of the parasite's chronic forms. Significantly, our investigation establishes the crucial role of host endoplasmic reticulum (ER)-phagy in the parasite's persistence within the host during latent infection.

The CD8+ T cell content of transbronchial biopsies from patients with a first episode of clinically stable grade A1 cellular rejection is associated with future chronic lung allograft dysfunction.

BACKGROUND: T cells drive acute cellular rejection (ACR) and its progression to chronic lung allograft dysfunction (CLAD) following lung transplantation. International Society for Heart and Lung Transplantation grade A1 ACR without associated allograft dysfunction is often untreated, yet some patients develop progressive graft dysfunction. T-cell composition of A1 ACR lesions may have prognostic value; therefore, protein-level and epigenetic techniques were applied to transbronchial biopsy tissue to determine whether differential T-cell infiltration in recipients experiencing a first episode of stable grade A1 ACR (StA1R) is associated with early CLAD. METHODS: Sixty-two patients experiencing a first episode of StA1R were divided into those experiencing CLAD within 2 years (n = 13) and those remaining CLAD-free for 5 or more years (n = 49). Imaging mass cytometry (IMC) was used to profile the spectrum and distribution of intragraft T cell phenotypes on a subcohort (n = 16; 8 early-CLAD and 8 no early-CLAD). Immunofluorescence was used to quantify CD4+, CD8+, and FOXP3+ cells. Separately, CD3+ cells were fluorescently labeled, micro-dissected, and the degree of Treg-specific demethylated region methylation was determined. RESULTS: PhenoGraph unsupervised clustering on IMC revealed 50 unique immune cell subpopulations. Methylation and immunofluorescence analyses demonstrated no significant differences in Tregs between early-CLAD and no early-CLAD groups. Immunofluorescence revealed that patients who developed CLAD within 2 years of lung transplantation showed greater CD8+ T cell infiltration compared to those who remained CLAD-free for 5 or more years. CONCLUSIONS: In asymptomatic patients with a first episode of A1 rejection, greater CD8+ T cell content may be indicative of worse long-term outlook.

Prevalence of Rathke Cleft and Other Incidental Pituitary Gland Findings on Contrast-Enhanced 3D Fat-Saturated T1 MPRAGE at 7T MRI.

BACKGROUND AND PURPOSE: A cleftlike nonenhancing hypointensity was observed repeatedly in the pituitary gland at the adenohypophysis/neurohypophysis border on contrast-enhanced 3D fat-saturated T1-MPRAGE using clinical 7T MRI. Our primary goal was to assess the prevalence of this finding. The secondary goals were to evaluate the frequency of other incidental pituitary lesions, MRI artifacts, and their effect on pituitary imaging on the contrast-enhanced 3D fat-saturated T1 MPRAGE at 7T. MATERIALS AND METHODS: One hundred patients who underwent 7T neuroimaging between October 27, 2021, and August 10, 2023, were included. Each case was evaluated for cleftlike pituitary hypointensity, pituitary masses, and artifacts on contrast-enhanced 3D fat-saturated T1 MPRAGE. Follow-up examinations were evaluated if present. The average prevalence for each finding was calculated, as were descriptive statistics for age and sex. RESULTS: A cleftlike hypointensity was present in 66% of 7T MRIs. There were no significant differences between the "cleftlike present" and "cleftlike absent" groups regarding sex (P = .39) and age (P = .32). The cleftlike hypointensity was demonstrated on follow-up MRIs in 3/3 patients with 7T, 1/12 with 3T, and 1/5 with 1.5T. A mass was found in 22%, while 75% had no mass and 3% were indeterminate. A mass was found in 18 (27%) of the cleftlike present and 4 (13%) of the cleftlike absent groups. The most common mass types were Rathke cleft cyst in 7 (31.8%) patients, "Rathke cleft cyst versus entrapped CSF" in 6 (27.3%), and microadenoma in 6 (22.2%) in the cleftlike present group. There were no significant differences in the mass types between the cleftlike present and cleftlike absent groups (P = .23). Susceptibility and/or motion artifacts were frequent using contrast-enhanced 3D fat-saturated T1 MPRAGE (54%). Artifact-free scans were significantly more frequent in the cleftlike present group (P = .03). CONCLUSIONS: A cleftlike nonenhancing hypointensity was frequently seen on the contrast-enhanced 3D fat-saturated T1 MPRAGE images at 7T MRI, which most likely represents a normal embryologic Rathke cleft remnant and cannot be seen in lower-field-strength MRIs. Susceptibility and motion artifacts are common in the sella. They may affect image quality, and the artifacts at 7T may lead to an underestimation of the prevalence of the Rathke cleft and other incidental findings.

Spatial prioritization for widespread invasive species control: Trade-offs between current impact and future spread.

Spatially explicit prioritization of invasive species control is a complex issue, requiring consideration of trade-offs between immediate and future benefits. This study aimed to prioritize management efforts to account for current and future threats from widespread invasions and examine the strength of the trade-off between these different management goals. As a case study, we identified spatially explicit management priorities for the widespread invasion of introduced willow into riparian and wetland habitats across a 102,145-km2 region in eastern Australia. In addition to targeting places where willow threatens biodiversity now, a second set of management goals was to limit reinfestation and further spread that could occur via two different mechanisms (downstream and by wind). A model of likely willow distribution across the region was combined with spatial data for biodiversity (native vegetation, threatened species and communities), ecological conditions, management costs, and two potential dispersal layers. We used systematic conservation planning software (Zonation) to prioritize where willow management should be focussed across more than 100,000 catchments for a range of different scenarios that reflected different weights between management goals. For willow invasion, we found that we could prioritize willow management to reduce the future threat of dispersal downstream with little reduction in the protection of biodiversity. However, accounting for future threats from wind dispersal resulted in a stronger trade-off with protection of threatened biodiversity. The strongest trade-off was observed when both dispersal mechanisms were considered together. This study shows that considering current and future goals together offers the potential to substantially improve conservation outcomes for invasive species management. Our approach also informs land managers about the relative trade-offs among different management goals under different control scenarios, helping to make management decisions more transparent. This approach can be used for other widespread invasive species to help improve invasive species management decisions.

The AusTraits plant dictionary.

Traits with intuitive names, a clear scope and explicit description are essential for all trait databases. The lack of unified, comprehensive, and machine-readable plant trait definitions limits the utility of trait databases, including reanalysis of data from a single database, or analyses that integrate data across multiple databases. Both can only occur if researchers are confident the trait concepts are consistent within and across sources. Here we describe the AusTraits Plant Dictionary (APD), a new data source of terms that extends the trait definitions included in a recent trait database, AusTraits. The development process of the APD included three steps: review and formalisation of the scope of each trait and the accompanying trait description; addition of trait metadata; and publication in both human and machine-readable forms. Trait definitions include keywords, references, and links to related trait concepts in other databases, enabling integration of AusTraits with other sources. The APD will both improve the usability of AusTraits and foster the integration of trait data across global and regional plant trait databases.

Patisiran, an RNAi therapeutic for hereditary transthyretin-mediated amyloidosis: Sub-analysis in Taiwanese patients from the APOLLO study.

BACKGROUND: To examine the efficacy and safety of patisiran, an RNA interference therapeutic, in patients from Taiwan with hereditary transthyretin-mediated (hATTR) amyloidosis with polyneuropathy. METHODS: The APOLLO phase 3 trial included patients from Taiwan who received patisiran 0.3 mg/kg intravenously or placebo once every 3 weeks (q3w) for 18 months (18 M), followed by patisiran 0.3 mg/kg q3w in an ongoing global open-label extension (OLE) study. The primary endpoint was change from baseline in modified Neuropathy Impairment Score +7 (mNIS+7) at 18 M. RESULTS: Eighteen Taiwanese patients were enrolled in APOLLO (patisiran, n = 8; placebo, n = 10; all A97S gene variant) and 14 continued in the global OLE. In this Taiwanese sub-population, beneficial treatment effects at 18 M were observed in mNIS+7 (least squares mean difference in change from baseline [patisiran-placebo], -26.5 points; 95% confidence interval: -45.5, -7.5). Patients who switched from placebo to patisiran demonstrated slowing of polyneuropathy progression at month 12 in the global OLE, while those who received patisiran in APOLLO maintained the beneficial treatment effects. Patisiran had an acceptable safety profile in the Taiwanese sub-population. CONCLUSION: This analysis suggests that patisiran is well tolerated and may provide a substantial clinical benefit for Taiwanese patients with hATTR amyloidosis with polyneuropathy. TRIAL REGISTRATION INFORMATION: The studies were registered on the ClinicalTrials.gov. The APOLLO study ClinicalTrials.gov identifier is NCT01960348 (https://clinicaltrials.gov/ct2/show/NCT01960348), with the registration date of October 10, 2013, and the first patient was enrolled on December 13, 2013. For the global OLE, the ClinicalTrials.gov identifier is NCT02510261 (https://clinicaltrials.gov/ct2/show/NCT02510261) with the registration date of July 29, 2015, and the first patient was enrolled on July 13, 2015. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that treatment with patisiran is safe and efficacious in Taiwanese patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy.

Impact of patisiran on health status and quality of life in patients with transthyretin cardiac amyloidosis

INTRODUCTION APOLLO-B is a Phase 3 study of patisiran in patients with transthyretin (ATTR) cardiac amyloidosis (NCT03997383), which demonstrated a significant benefit in functional capacity (6-MWT), and health status and quality of life (QoL) (KCCQ-OS) with patisiran vs placebo at Month (M) 12. HYPOTHESIS Patisiran improves health status and QoL in the daily lives of patients with ATTR cardiac amyloidosis vs placebo. METHODS Patients were 18-85 years old with ATTR amyloidosis and a medical history of heart failure (HF) due to ATTR cardiomyopathy, with ≥1 prior hospitalization for HF or current clinical evidence of HF. Patients were randomized (1:1) to intravenous patisiran 0.3 mg/kg or placebo every 3 weeks. These post-hoc analyses evaluated percentage of responders reporting ≥5-point improvement in KCCQ-OS, and change from baseline in 4 KCCQ domains and questions within the domains. RESULTS 359 patients received study drug (patisiran, N=181; placebo, N=178): median age (range), 76 (41, 85) years; male, 89%; wild-type ATTR, 80%; 25% were on tafamidis at baseline. At M12, patisiran showed significant benefit vs placebo in KCCQ-OS (LS mean [SEM] change from baseline: patisiran, 0.30 [1.26]; placebo, -3.41 [1.28]; LS mean [SEM] difference: 3.71 [1.80]; p=0.0397). A ≥ 5-point improvement in KCCQ at M12 was more frequent with patisiran vs placebo (34.1 vs 24.0%: difference [95% CI] 10.1% [0.7, 19.5]). Improvement vs placebo was consistent across domains, with LS mean differences [95% CI] in change from baseline (patisiran - placebo) in Physical Limitations (2.75 [-1.24, 6.74]), Total Symptoms (4.55 [0.75, 8.34]), QoL (4.27 [-0.12, 8.65]), and Social Limitations (2.76 [-2.21, 7.73]). Categorical changes from baseline to M12 demonstrated greater percentages of placebo-treated patients reporting worsening for questions in each domain, including activities requiring greater cardiometabolic demand. In patients with values at baseline and M12, notably greater percentages (>5%) of placebo- vs patisiran-treated patients reported worsening (percent difference; n=placebo/patisiran) for questions related to Walking 1 Block on Level Ground (10%; n=159/162), Frequency and Burden of Dyspnea (9.5% and 7.6%; n=164/170), Frequency of Orthopnea (9.6%; n=163/170), Feeling about Spending the Rest of Their Life with HF the Way It Is Right Now (6.4%; n=164/170), and Intimate Relationships (6.3%; n=88/86). Improvement from baseline was reported by greater percentages (>5%) of patisiran-treated patients (percent difference; n=patisiran/placebo) in Enjoyment of Life Limited Due to HF (12.8%; n=170/164) and Hobbies/Recreational Activities (6.0%; n=141/143). CONCLUSIONS In APOLLO-B, improvements in health status and QoL with patisiran vs placebo were apparent across all 4 KCCQ domains. Greater percentages of patisiran-treated patients had KCCQ-OS improved by ≥ 5 points at M12 and they more often reported improvements in QoL, and ability to enjoy life and perform hobbies/recreational activities. More placebo-treated patients reported worsening in walking on level ground, HF symptoms and QoL.

Oxonium ion scanning mass spectrometry for large-scale plasma glycoproteomics.

Protein glycosylation, a complex and heterogeneous post-translational modification that is frequently dysregulated in disease, has been difficult to analyse at scale. Here we report a data-independent acquisition technique for the large-scale mass-spectrometric quantification of glycopeptides in plasma samples. The technique, which we named 'OxoScan-MS', identifies oxonium ions as glycopeptide fragments and exploits a sliding-quadrupole dimension to generate comprehensive and untargeted oxonium ion maps of precursor masses assigned to fragment ions from non-enriched plasma samples. By applying OxoScan-MS to quantify 1,002 glycopeptide features in the plasma glycoproteomes from patients with COVID-19 and healthy controls, we found that severe COVID-19 induces differential glycosylation in IgA, haptoglobin, transferrin and other disease-relevant plasma glycoproteins. OxoScan-MS may allow for the quantitative mapping of glycoproteomes at the scale of hundreds to thousands of samples.

Host autophagy is exploited by the intracellular parasite Toxoplasma gondii to enhance amino acids levels.

Toxoplasma gondii, a widespread parasite, has the ability to infect nearly any nucleated cell in warm-blooded vertebrates. It is estimated that around 2 billion people globally have been infected by this pathogen. Although most healthy individuals can effectively control parasite replication, certain parasites may evade the immune response, establishing cysts in the brain that are refractory to the immune system and resistance to available drugs. For its chronic persistence in the brain, the parasite relies on host cells' nutrients, particularly amino acids and lipids. Therefore, understanding how latent parasites persist in the brain is crucial for identifying potential drug targets against chronic forms. While shielded within parasitophorous vacuoles (PVs) or cysts, Toxoplasma exploits the host endoplasmic reticulum (ER) metabolism to sustains its persistence in the brain, resulting in host neurological alterations. In this study, we demonstrate that T. gondii disrupts the host ER homeostasis, resulting in accumulation of unfolded protein with the host ER. The host counters this stress by initiating an autophagic pathway known as ER-phagy, which breaks down unfolded proteins into amino acids, promoting their recycling. Remarkably, the persistence of latent forms in cell culture as well as behavioral changes in mice caused by the latent infection could be successfully reversed by restricting the availability of various amino acids during T. gondi infection. Our findings unveil the underlying mechanisms employed by T. gondii to exploit host ER and lysosomal pathways, enhancing nutrient levels during infection. These insights provide new strategies for the treatment of toxoplasmosis. Importance: Intracellular parasites employ several mechanisms to manipulate the cellular environment, enabling them to persist in the host. Toxoplasma gondii , a single-celled parasite, possesses the ability to infect virtually any nucleated cell of warm-blooded vertebrates, including nearly 2 billion people worldwide. Unfortunately, existing treatments and immune responses are not entirely effective in eliminating the chronic persisting forms of the parasite. This study reveals that T. gondii induces the host's autophagic pathway to boost amino acid levels in infected cells. The depletion of amino acids, in turn, influences the persistence of the parasite's chronic forms, resulting in a reduction of neurological alterations caused by chronic infection in mice. Significantly, our investigation establishes the crucial role of host ER-phagy in the parasite's persistence within the host during latent infection.

APOLLO-B, a study of patisiran in patients with transthyretin cardiac amyloidosis: primary long-term results from the open-label extension period

INTRODUCTION: The Phase 3 APOLLO-B study evaluates patisiran in patients (pts) with transthyretin (ATTR) cardiac amyloidosis over a 12-month (M) double-blind (DB) period, followed by an open-label extension (OLE) period when all pts receive patisiran (NCT03997383). Hypothesis: Patisiran provides long-term benefit in pts with ATTR cardiac amyloidosis. Aims: Describe safety and efficacy of patisiran during the APOLLO-B OLE (18M+). METHODS: Pts (18-85 yrs) with ATTR cardiac amyloidosis and heart failure history were randomized 1:1 to patisiran or placebo (pbo). Pts completing DB period were eligible to receive patisiran in the OLE for ≤36M. Results summarized based on DB treatment arm. Exploratory assessments include change from study baseline (CFB) in 6-minute walk test (6MWT), KCCQ-OS, NT-proBNP, and troponin I. RESULTS: In the DB period, 359 pts (pbo n=178; patisiran n=181) received study drug (median [range] age, 76.0 [41, 85] yrs; male, 89%; wtATTR, 80%; tafamidis at baseline, 25%); 334 (93%) entered the OLE. In patisiran arm, M12 and M18 results, respectively, were similar for each endpoint: 6MWT and KCCQ-OS (mean [SEM] CFB) −8.09 [5.73] vs −9.21 [6.04] meters (m) and 0.60 [1.36] vs 0.22 [1.48]; NT-proBNP and troponin I (geometric mean fold-CFB [95%CI]) 1.10 [1.03, 1.17] vs 1.17 [1.07, 1.27] and 1.11 [1.05, 1.18] vs 1.09 [1.01, 1.17]). In pbo arm, patisiran initiation in OLE was associated with a slower rate of worsening or relative stability across endpoints; CFB at M12 vs M18, respectively: 6MWT, −25.43 [5.61] vs −31.08 [5.45] m; KCCQ-OS, −3.41 [1.33] vs −4.02 [1.49]; NT-proBNP, 1.39 [1.28, 1.51] vs 1.53 [1.38, 1.71]; and troponin I, 1.29 [1.21, 1.38] vs 1.21 [1.13, 1.30]. Patisiran had an acceptable safety profile; no new concerns. OLE analyses are ongoing; updated data to be presented. CONCLUSIONS: The M18 results provide evidence that beneficial effects observed in DB period on functional capacity, health status, and quality of life were maintained by continued treatment with patisiran during the OLE. Pbo-treated pts initiating patisiran at M12 showed slowed worsening or stabilization in most endpoints at M18. Early treatment initiation is important: pbo-treated pts did not recover functional capacity or health lost prior to initiating OLE patisiran.

Single cell analysis of dup15q syndrome reveals developmental and postnatal molecular changes in autism.

Duplication 15q (dup15q) syndrome is the most common genetic cause of autism spectrum disorder (ASD). Due to a higher genetic and phenotypic homogeneity compared to idiopathic autism, dup15q syndrome provides a well-defined setting to investigate ASD mechanisms. Previous bulk gene expression studies identified shared molecular changes in ASD. However, how cell type specific changes compare across different autism subtypes and how they change during development is largely unknown. In this study, we used single cell and single nucleus mRNA sequencing of dup15q cortical organoids from patient iPSCs, as well as post-mortem patient brain samples. We find cell-type specific dysregulated programs that underlie dup15q pathogenesis, which we validate by spatial resolved transcriptomics using brain tissue samples. We find degraded identity and vulnerability of deep-layer neurons in fetal stage organoids and highlight increased molecular burden of postmortem upper-layer neurons implicated in synaptic signaling, a finding shared between idiopathic ASD and dup15q syndrome. Gene co-expression network analysis of organoid and postmortem excitatory neurons uncovers modules enriched with autism risk genes. Organoid developmental modules were involved in transcription regulation via chromatin remodeling, while postmortem modules were associated with synaptic transmission and plasticity. The findings reveal a shifting landscape of ASD cellular vulnerability during brain development.

Patisiran Treatment in Patients with Transthyretin Cardiac Amyloidosis.

BACKGROUND: Transthyretin amyloidosis, also called ATTR amyloidosis, is associated with accumulation of ATTR amyloid deposits in the heart and commonly manifests as progressive cardiomyopathy. Patisiran, an RNA interference therapeutic agent, inhibits the production of hepatic transthyretin. METHODS: In this phase 3, double-blind, randomized trial, we assigned patients with hereditary, also known as variant, or wild-type ATTR cardiac amyloidosis, in a 1:1 ratio, to receive patisiran (0.3 mg per kilogram of body weight) or placebo once every 3 weeks for 12 months. A hierarchical procedure was used to test the primary and three secondary end points. The primary end point was the change from baseline in the distance covered on the 6-minute walk test at 12 months. The first secondary end point was the change from baseline to month 12 in the Kansas City Cardiomyopathy Questionnaire-Overall Summary (KCCQ-OS) score (with higher scores indicating better health status). The second secondary end point was a composite of death from any cause, cardiovascular events, and change from baseline in the 6-minute walk test distance over 12 months. The third secondary end point was a composite of death from any cause, hospitalizations for any cause, and urgent heart failure visits over 12 months. RESULTS: A total of 360 patients were randomly assigned to receive patisiran (181 patients) or placebo (179 patients). At month 12, the decline in the 6-minute walk distance was lower in the patisiran group than in the placebo group (Hodges-Lehmann estimate of median difference, 14.69 m; 95% confidence interval [CI], 0.69 to 28.69; P = 0.02); the KCCQ-OS score increased in the patisiran group and declined in the placebo group (least-squares mean difference, 3.7 points; 95% CI, 0.2 to 7.2; P = 0.04). Significant benefits were not observed for the second secondary end point. Infusion-related reactions, arthralgia, and muscle spasms occurred more often among patients in the patisiran group than among those in the placebo group. CONCLUSIONS: In this trial, administration of patisiran over a period of 12 months resulted in preserved functional capacity in patients with ATTR cardiac amyloidosis. (Funded by Alnylam Pharmaceuticals; APOLLO-B ClinicalTrials.gov number, NCT03997383.).

'Chip'-ing away at morphogenesis - application of organ-on-chip technologies to study tissue morphogenesis.

Emergent cell behaviors that drive tissue morphogenesis are the integrated product of instructions from gene regulatory networks, mechanics and signals from the local tissue microenvironment. How these discrete inputs intersect to coordinate diverse morphogenic events is a critical area of interest. Organ-on-chip technology has revolutionized the ability to construct and manipulate miniaturized human tissues with organotypic three-dimensional architectures in vitro. Applications of organ-on-chip platforms have increasingly transitioned from proof-of-concept tissue engineering to discovery biology, furthering our understanding of molecular and mechanical mechanisms that operate across biological scales to orchestrate tissue morphogenesis. Here, we provide the biological framework to harness organ-on-chip systems to study tissue morphogenesis, and we highlight recent examples where organ-on-chips and associated microphysiological systems have enabled new mechanistic insight in diverse morphogenic settings. We further highlight the use of organ-on-chip platforms as emerging test beds for cell and developmental biology.

Notch1 cortical signaling regulates epithelial architecture and cell-cell adhesion.

Notch receptors control tissue morphogenic processes that involve coordinated changes in cell architecture and gene expression, but how a single receptor can produce these diverse biological outputs is unclear. Here, we employ a 3D model of a human ductal epithelium to reveal tissue morphogenic defects result from loss of Notch1, but not Notch1 transcriptional signaling. Instead, defects in duct morphogenesis are driven by dysregulated epithelial cell architecture and mitogenic signaling which result from the loss of a transcription-independent, Notch1 cortical signaling mechanism that ultimately functions to stabilize adherens junctions and cortical actin. We identify that Notch1 localization and cortical signaling are tied to apical-basal cell restructuring and discover that a Notch1-FAM83H interaction underlies control of epithelial adherens junctions and cortical actin. Together, these results offer new insights into Notch1 signaling and regulation and advance a paradigm in which transcriptional and cell adhesive programs might be coordinated by a single receptor.

LIF signaling regulates outer radial glial to interneuron fate during human cortical development.

Radial glial (RG) development is essential for cerebral cortex growth and organization. In humans, the outer radial glia (oRG) subtype is expanded and gives rise to diverse neurons and glia. However, the mechanisms regulating oRG differentiation are unclear. oRG cells express leukemia-inhibitory factor (LIF) receptors during neurogenesis, and consistent with a role in stem cell self-renewal, LIF perturbation impacts oRG proliferation in cortical tissue and organoids. Surprisingly, LIF treatment also increases the production of inhibitory interneurons (INs) in cortical cultures. Comparative transcriptomic analysis identifies that the enhanced IN population resembles INs produced in the caudal ganglionic eminence. To evaluate whether INs could arise from oRGs, we isolated primary oRG cells and cultured them with LIF. We observed the production of INs from oRG cells and an increase in IN abundance following LIF treatment. Our observations suggest that LIF signaling regulates the capacity of oRG cells to generate INs.

A cross-species proteomic map reveals neoteny of human synapse development.

The molecular mechanisms and evolutionary changes accompanying synapse development are still poorly understood1,2. Here we generate a cross-species proteomic map of synapse development in the human, macaque and mouse neocortex. By tracking the changes of more than 1,000 postsynaptic density (PSD) proteins from midgestation to young adulthood, we find that PSD maturation in humans separates into three major phases that are dominated by distinct pathways. Cross-species comparisons reveal that human PSDs mature about two to three times slower than those of other species and contain higher levels of Rho guanine nucleotide exchange factors (RhoGEFs) in the perinatal period. Enhancement of RhoGEF signalling in human neurons delays morphological maturation of dendritic spines and functional maturation of synapses, potentially contributing to the neotenic traits of human brain development. In addition, PSD proteins can be divided into four modules that exert stage- and cell-type-specific functions, possibly explaining their differential associations with cognitive functions and diseases. Our proteomic map of synapse development provides a blueprint for studying the molecular basis and evolutionary changes of synapse maturation.

Proteome-wide structural analysis identifies warhead- and coverage-specific biases in cysteine-focused chemoproteomics.

Covalent drug discovery has undergone a resurgence over the past two decades and reactive cysteine profiling has emerged in parallel as a platform for ligand discovery through on- and off-target profiling; however, the scope of this approach has not been fully explored at the whole-proteome level. We combined AlphaFold2-predicted side-chain accessibilities for >95% of the human proteome with a meta-analysis of eighteen public cysteine profiling datasets, totaling 44,187 unique cysteine residues, revealing accessibility biases in sampled cysteines primarily dictated by warhead chemistry. Analysis of >3.5 million cysteine-fragment interactions further showed that hit elaboration and optimization drives increased bias against buried cysteine residues. Based on these data, we suggest that current profiling approaches cover a small proportion of potential ligandable cysteine residues and propose future directions for increasing coverage, focusing on high-priority residues and depth. All analysis and produced resources are freely available and extendable to other reactive amino acids.