Dysregulation of the WNK4-SPAK/OSR1 pathway has a minor effect on baseline NKCC2 phosphorylation.

The with-no-lysine kinase 4 (WNK4)-sterile 20/SPS-1-related proline/alanine-rich kinase (SPAK)/oxidative stress-responsive kinase 1 (OSR1) pathway mediates activating phosphorylation of the furosemide-sensitive Na+-K+-2Cl- cotransporter (NKCC2) and the thiazide-sensitive NaCl cotransporter (NCC). The commonly used pT96/pT101-pNKCC2 antibody cross-reacts with pT53-NCC in mice on the C57BL/6 background due to a five amino acid deletion. We generated a new C57BL/6-specific pNKCC2 antibody (anti-pT96-NKCC2) and tested the hypothesis that the WNK4-SPAK/OSR1 pathway strongly regulates the phosphorylation of NCC but not NKCC2. In C57BL/6 mice, anti-pT96-NKCC2 detected pNKCC2 and did not cross-react with NCC. Abundances of pT96-NKCC2 and pT53-NCC were evaluated in Wnk4-/-, Osr1-/-, Spak-/-, and Osr1-/-/Spak-/- mice and in several models of the disease familial hyperkalemic hypertension (FHHt) in which the CUL3-KLHL3 ubiquitin ligase complex that promotes WNK4 degradation is dysregulated (Cul3+/-/Δ9, Klhl3-/-, and Klhl3R528H/R528H). All mice were on the C57BL/6 background. In Wnk4-/- mice, pT53-NCC was almost absent but pT96-NKCC2 was only slightly lower. pT53-NCC was almost absent in Spak-/- and Osr1-/-/Spak-/- mice, but pT96-NKCC2 abundance did not differ from controls. pT96-NKCC2/total NKCC2 was slightly lower in Osr1-/- and Osr1-/-/Spak-/- mice. WNK4 expression colocalized not only with NCC but also with NKCC2 in Klhl3-/- mice, but pT96-NKCC2 abundance was unchanged. Consistent with this, furosemide-induced urinary Na+ excretion following thiazide treatment was similar between Klhl3-/- and controls. pT96-NKCC2 abundance was also unchanged in the other FHHt mouse models. Our data show that disruption of the WNK4-SPAK/OSR1 pathway only mildly affects NKCC2 phosphorylation, suggesting a role for other kinases in NKCC2 activation. In FHHt models NKCC2 phosphorylation is unchanged despite higher WNK4 abundance, explaining the thiazide sensitivity of FHHt.NEW & NOTEWORTHY The renal cation cotransporters NCC and NKCC2 are activated following phosphorylation mediated by the WNK4-SPAK/OSR1 pathway. While disruption of this pathway strongly affects NCC activity, effects on NKCC2 activity are unclear since the commonly used phospho-NKCC2 antibody was recently reported to cross-react with phospho-NCC in mice on the C57BL/6 background. Using a new phospho-NKCC2 antibody specific for C57BL/6, we show that inhibition or activation of the WNK4-SPAK/OSR1 pathway in mice only mildly affects NKCC2 phosphorylation.

Craniofacial features of POLR3-related leukodystrophy caused by biallelic variants in POLR3A, POLR3B and POLR1C.

BACKGROUND: RNA polymerase III-related or 4H leukodystrophy (POLR3-HLD) is an autosomal recessive hypomyelinating leukodystrophy characterized by neurological dysfunction, hypodontia and hypogonadotropic hypogonadism. The disease is caused by biallelic pathogenic variants in POLR3A, POLR3B, POLR1C or POLR3K. Craniofacial abnormalities reminiscent of Treacher Collins syndrome have been originally described in patients with POLR3-HLD caused by biallelic pathogenic variants in POLR1C. To date, no published studies have appraised in detail the craniofacial features of patients with POLR3-HLD. In this work, the specific craniofacial characteristics of patients with POLR3-HLD associated with biallelic pathogenic variants in POLR3A, POLR3B and POLR1C are described. METHODS: The craniofacial features of 31 patients with POLR3-HLD were evaluated, and potential genotype-phenotype associations were evaluated. RESULTS: Various craniofacial abnormalities were recognized in this patient cohort, with each individual presenting at least one craniofacial abnormality. The most frequently identified features included a flat midface (61.3%), a smooth philtrum (58.0%) and a pointed chin (51.6%). In patients with POLR3B biallelic variants, a thin upper lip was frequent. Craniofacial anomalies involving the forehead were most commonly associated with biallelic variants in POLR3A and POLR3B while a higher proportion of patients with POLR1C biallelic variants demonstrated bitemporal narrowing. CONCLUSION: Through this study, we demonstrated that craniofacial abnormalities are common in patients with POLR3-HLD. This report describes in detail the dysmorphic features of POLR3-HLD associated with biallelic variants in POLR3A, POLR3B and POLR1C.

[Analysis of the efficacy and safety of dual immunotherapy in patients with driver gene and programmed death ligand-1 double negative advanced non-small cell lung cancer].

Objective: To discuss the efficacy and safety of the dual immunotherapy of nivolumab plus ipilimumab in patients with advanced non-small cell lung cancer (NSCLC) who are double negative for driver gene and programmed death-ligand 1 (PD-L1) expression. Methods: We conducted a retrospective collection of clinical data for 61 patients with advanced NSCLC who were negative for both driver genes and PD-L1 and received dual immunotherapy with nivolumab plus ipilimumab at the First Affiliated Hospital of Guangzhou Medical University from January 2019 to June 2023. Based on treatment conditions, patients were divided into first-line and non-first-line dual immunotherapy groups. Patients were followed up monthly, with the follow-up period ending on October 1, 2023. The efficacy was evaluated using Solid Tumor Response Evaluation Criteria, and adverse reactions were assessed according to the Common Terminology Criteria for Adverse Events developed by the National Cancer Institute in the United States. Survival curves were plotted using the Kaplan-Meier method, and the log-rank test was used to compare the differences in progression-free survival (PFS) and overall survival (OS) between first-line and non-first-line dual immunotherapy patients. The influence factors of PFS were analyzed using a multivariate Cox proportional hazards regression model. Results: Among the 61 NSCLC patients, 49 were male (80.3%), with an age range of 23-88 years [(65.3±7.4) years]. There were 14 cases (23.0%) classified as stage ⅢC and 47 cases (77.0%) classified as stage Ⅳ according to TNM staging. Forty cases (65.6%) received non-first-line treatment. The objective response rate (ORR) was 24.6% (15/61), and the disease control rate (DCR) was 52.5% (32/61). All 61 patients were followed up, with a median follow-up time of 17.8 months. The median PFS was 6.0 months (95%CI: 5.5-6.4 months), and the median OS was 17.0 months (95%CI: 14.8-19.2 months). For patients receiving first-line dual immunotherapy, the median PFS was longer than for those receiving non-first-line dual immunotherapy [7.0 months (95%CI: 6.0-7.9 months) vs 4.0 months (95%CI: 3.3-4.6 months), P<0.001]; similarly, the median OS for patients receiving first-line dual immunotherapy was longer than for those receiving non-first-line dual immunotherapy [19.0 months (95%CI: 18.1-19.9 months) vs 13.0 months (95%CI: 10.8-15.1 months), P<0.001]. Multivariate Cox risk regression model analysis showed that distant tumor metastasis (HR=1.414, 95%CI: 1.253-1.725), non-first-line dual immunotherapy (HR=1.412, 95%CI: 1.184-1.652), and tumor mutation burden<10 mut/Mb (HR=1.328, 95%CI: 1.151-1.546) were risk factors for PFS, while non-squamous carcinoma (HR=0.917, 95%CI: 0.823-0.984) was a protective factor for PFS. Immune-related adverse reactions occurred in 41 cases (67.2%), including 21 cases (32.8%) of grade 3-4 adverse reactions. Eight cases (13.1%) discontinued treatment, and there were no deaths. Conclusions: Dual immunotherapy with nivolumab plus ipilimumab can be a treatment option for driver gene and PD-L1 double-negative advanced NSCLC. Distant tumor metastasis, non-first-line dual immunotherapy, and tumor mutation burden<10 mut/Mb are risk factors affecting patients' PFS, while non-squamous cell carcinoma is a protective factor affecting patients' PFS.

[Survival analysis of 37 cases of malignant mesothelioma].

Objective: To explore the relationship between clinicopathological features, treatment and prognosis of patients with malignant mesothelioma, and provide theoretical basis for the prevention and treatment of malignant mesothelioma. Methods: In November 2022, the clinical data of 37 patients with malignant mesothelioma diagnosed in Qingdao Central Hospital from July 2014 to November 2022 were retrospectively analyzed, and the prognostic factors were analyzed by Kaplan-Meier and log-rank tests. Results: The median age of the 37 patients was 66 years old, all patients were confirmed by pathology. The median survival time of all patients was 30.00 months. The 1-year, 2-year, 3-year and 5-year cumulative survival rates were 70.27% (26/37), 48.65% (18/37), 16.22% (6/37) and 13.51% (5/37), respectively. Compared with different treatments, the median survival time of palliative care patients was 5.00 months, which was significantly lower than that of operation group (30.33 months), chemotherapy group (30.00 months), surgery combined with chemotherapy group (30.00 months) and chemotherapy combined with bevacizumab targeted therapy group (47.42 months) (P<0.05). Gender, age (≥60 years old or <60 years old), smoking history, occupational exposure history, disease site, and surgical history were not factors affecting the survival of malignant mesothelioma patients (P>0.05) . Conclusion: The clinical symptoms of malignant mesothelioma are not specific, but early initiation of treatment can still prolong survival, and chemotherapy combined with anti-vascular targeted therapy shows better therapeutic effect.

Insights into the synthesis strategies of plant-derived cyclotides.

Cyclotides are plant peptides characterized with a head-to-tail cyclized backbone and three interlocking disulfide bonds, known as a cyclic cysteine knot. Despite the variations in cyclotides peptide sequences, this core structure is conserved, underlying their most useful feature: stability against thermal and chemical breakdown. Cyclotides are the only natural peptides known to date that are orally bioavailable and able to cross cell membranes. Cyclotides also display bioactivities that have been exploited and expanded to develop as potential therapeutic reagents for a wide range of conditions (e.g., HIV, inflammatory conditions, multiple sclerosis, etc.). As such, in vitro production of cyclotides is of the utmost importance since it could assist further research on this peptide class, specifically the structure-activity relationship and its mechanism of action. The information obtained could be utilized to assist drug development and optimization. Here, we discuss several strategies for the synthesis of cyclotides using both chemical and biological routes.

[Validation study of the Chinese version of atopic dermatitis control tool].

To assess the reliability, validity and responsiveness of the Chinese version of the atopic dermatitis control tool (ADCT). After this study obtained authorization for the Chinese version of the ADCT scale. 114 patients with atopic dermatitis were enrolled from the Department of Dermatology, Peking University First Hospital using convenience sampling from October 2022. Patients were surveyed using the General Information Questionnaire, Chinese version of ADCT, patient-oriented eczema measure (POEM),peak pruritus numerical rating scale (PP-NRS),dermatology life quality index (DLQI) and the global patient self-assessment for disease severity. Mann-Whitney rank sum test and Spearman correlation analysis were used for item analysis; content validity was assessed using content validity index (CVI); exploratory factor analysis was used to assess structural validity; Cronbach' alpha coefficient was used to assess internal consistency; Spearman correlation analysis was used to assess the correlation of ADCT with other scales to assess external responsiveness. The results showed that all items were retained by item analysis. I-CVI was 0.9-1, and S-CVI/Average was 0.983; the scale extracted one common factor by factor analysis, the cumulative variance explanation rate was 77.927%; the Cronbach' alpha coefficient of the scale was 0.937; the correlation coefficients of the Chinese version of ADCT with POEM, PP-NRS, and DLQI were 0.805, 0.861, and 0.709 respectively. In conclusion, the Chinese version of the ADCT has adequate reliability, validity and responsiveness, and is suitable for measuring disease control in Chinese patients with atopic dermatitis.

Cullin 3 mutant causing familial hyperkalemic hypertension lacks normal activity in the kidney.

Mutations in the ubiquitin ligase scaffold protein cullin 3 (CUL3) cause the disease familial hyperkalemic hypertension (FHHt). We recently reported that in the kidney, aberrant mutant CUL3 (CUL3-Δ9) activity lowers the abundance of CUL3-Δ9 and Kelch-like 3, the CUL3 substrate adaptor for with-no-lysine kinase 4 (WNK4) and that this is mechanistically important. However, whether CUL3-Δ9 exerts additional effects on other targets that may alter renal function is unclear. Here, we sought to determine 1) whether CUL3-Δ9 expression can rescue the phenotype of renal tubule-specific Cul3 knockout mice, and 2) whether CUL3-Δ9 expression affects other CUL3 substrates. Using an inducible renal tubule-specific system, we studied two CUL3-Δ9-expressing mouse models: Cul3 knockout (Cul3-/-/Δ9) and Cul3 heterozygous background (Cul3+/-/Δ9, FHHt model). The effects of CUL3-Δ9 in these mice were compared with Cul3-/- and Cul3+/- mice. Similar to Cul3-/- mice, Cul3-/-/Δ9 mice displayed polyuria with loss of aquaporin 2 and collecting duct injury; proximal tubule injury also occurred. CUL3-Δ9 did not promote degradation of two CUL3 targets that accumulate in the Cul3-/- kidney: high-molecular-weight (HMW) cyclin E and NAD(P)H:quinone oxidoreductase 1 (NQO1) [a surrogate for the CUL3-Kelch-like ECH-associated protein 1 (KEAP1) substrate nuclear factor erythroid-2-related factor 2]. Since CUL3-Δ9 expression cannot rescue the Cul3-/- phenotype, our data suggest that CUL3-Δ9 cannot normally function in ubiquitin ligase complexes. In Cul3+/-/Δ9 mice, KEAP1 abundance did not differ but NQO1 abundance was higher, suggesting adaptor sequestration by CUL3-Δ9 in vivo. Together, our results provide evidence that in the kidney, CUL3-Δ9 completely lacks normal activity and can trap CUL3 substrate adaptors in inactive complexes.NEW & NOTEWORTHY CUL3 mutation (CUL3-Δ9) causes familial hyperkalemic hypertension (FHHt) by reducing adaptor KLHL3, impairing substrate WNK4 degradation. Whether CUL3-Δ9 affects other targets in kidneys remains unclear. We found that CUL3-Δ9 cannot degrade two CUL3 targets, cyclin E and nuclear factor erythroid-2-related factor 2 (NRF2; using a surrogate marker NQO1), or rescue injury or polyuria caused by Cul3 disruption. In an FHHt model, CUL3-Δ9 impaired NRF2 degradation without reduction of its adaptor KEAP1. Our data provide additional insights into CUL3-Δ9 function in the kidney.

A Cockayne-like phenotype resulting from a de novo variant in MORC2: expanding the phenotype of MORC2-related disorders.

Cockayne syndrome is a rare inherited DNA repair multisystemic disorder. Here, we aim to raise awareness of the phenotypic resemblances between Cockayne syndrome and the neurodevelopmental disorder caused by pathogenic variants in MORC2, a gene also involved in DNA repair. Using exome sequencing, we identified a de novo pathogenic variant in MORC2 in our patient. Our patient's phenotype was characterized by multiple features evocative of Cockayne syndrome. Based on our patient's phenotype, in addition to the phenotypic description of patients with pathogenic variants in MORC2 reported in the literature, we suggest that pathogenic variants in this gene are associated with a Cockayne-like phenotype.

Asymmetric dimerization of adenosine deaminase acting on RNA facilitates substrate recognition.

Adenosine deaminases acting on RNA (ADARs) are enzymes that convert adenosine to inosine in duplex RNA, a modification that exhibits a multitude of effects on RNA structure and function. Recent studies have identified ADAR1 as a potential cancer therapeutic target. ADARs are also important in the development of directed RNA editing therapeutics. A comprehensive understanding of the molecular mechanism of the ADAR reaction will advance efforts to develop ADAR inhibitors and new tools for directed RNA editing. Here we report the X-ray crystal structure of a fragment of human ADAR2 comprising its deaminase domain and double stranded RNA binding domain 2 (dsRBD2) bound to an RNA duplex as an asymmetric homodimer. We identified a highly conserved ADAR dimerization interface and validated the importance of these sequence elements on dimer formation via gel mobility shift assays and size exclusion chromatography. We also show that mutation in the dimerization interface inhibits editing in an RNA substrate-dependent manner for both ADAR1 and ADAR2.

Bi-allelic Mutations in EPRS, Encoding the Glutamyl-Prolyl-Aminoacyl-tRNA Synthetase, Cause a Hypomyelinating Leukodystrophy.

Hypomyelinating leukodystrophies are genetic disorders characterized by insufficient myelin deposition during development. They are diagnosed on the basis of both clinical and MRI features followed by genetic confirmation. Here, we report on four unrelated affected individuals with hypomyelination and bi-allelic pathogenic variants in EPRS, the gene encoding cytoplasmic glutamyl-prolyl-aminoacyl-tRNA synthetase. EPRS is a bifunctional aminoacyl-tRNA synthetase that catalyzes the aminoacylation of glutamic acid and proline tRNA species. It is a subunit of a large multisynthetase complex composed of eight aminoacyl-tRNA synthetases and its three interacting proteins. In total, five different EPRS mutations were identified. The p.Pro1115Arg variation did not affect the assembly of the multisynthetase complex (MSC) as monitored by affinity purification-mass spectrometry. However, immunoblot analyses on protein extracts from fibroblasts of the two affected individuals sharing the p.Pro1115Arg variant showed reduced EPRS amounts. EPRS activity was reduced in one affected individual's lymphoblasts and in a purified recombinant protein model. Interestingly, two other cytoplasmic aminoacyl-tRNA synthetases have previously been implicated in hypomyelinating leukodystrophies bearing clinical and radiological similarities to those in the individuals we studied. We therefore hypothesized that leukodystrophies caused by mutations in genes encoding cytoplasmic aminoacyl-tRNA synthetases share a common underlying mechanism, such as reduced protein availability, abnormal assembly of the multisynthetase complex, and/or abnormal aminoacylation, all resulting in reduced translation capacity and insufficient myelin deposition in the developing brain.

Forkhead box protein-3 (Foxp3)-producing dendritic cells suppress allergic response.

BACKGROUND: The generation of the tolerogenic dendritic cells (DC) is not fully understood yet. Forkhead box protein-3 (Foxp3) is an important molecule in the immune tolerance. This study tests a hypothesis that DCs express Foxp3, which can be upregulated by Staphylococcal enterotoxin B (SEB). METHODS: The expression of Foxp3 by DCs was evaluated by real-time RT-PCR, Western blotting, flow cytometry, and chromatin immunoprecipitation assay. RESULTS: We observed that mice treated with SEB at 0.25-0.5 µg/mouse showed high frequencies of transforming growth factor (TGF)-ß-producing CD4+ T cells and TGF-ß-producing DCs in the intestine, while the IL-4+ CD4+ T cells and TIM4+ DCs were dominated in the intestine in mice treated with SEB at 1-10 µg/mouse. Treating DCs with SEB in the culture induced high levels of Foxp3 at the TGF-ß promoter locus. The function of Foxp3 was blocked by STAT6 (signal transducer and activator transcription-6); the latter was induced by exposing DCs to SEB in the culture at doses of 100-400 ng/ml. Treating allergic mice with specific immunotherapy (SIT) together with SEB significantly promoted the therapeutic effects on the allergic responses than treating with SIT alone. CONCLUSION: Dendritic cells have the capacity to express Foxp3, which can be upregulated by exposure to SEB.

POLR3A and POLR3B Mutations in Unclassified Hypomyelination.

OBJECTIVE: This study aims to ascertain frequency of mutations in POLR3A or POLR3B, which are associated with 4H leukodystrophy, in a cohort of patients with unclassified hypomyelination. METHODS AND RESULTS: In a cohort of 22 patients with the magnetic resonance imaging (MRI) diagnosis of unclassified hypomyelination and without typical clinical signs, we evaluated clinical and MRI features. Developmental delay or intellectual disability, ataxia, and spasticity were frequent symptoms. POLR3A and POLR3B were sequenced. A compound heterozygote mutation in POLR3B was found in only one patient. Additional investigations allowed a definitive diagnosis in 10 patients. CONCLUSION: Mutations in POLR3A or POLR3B are rare in patients with unclassified hypomyelination, and alternative diagnoses should be considered first.

A homozygous mutation in the NDUFS1 gene presents with a mild cavitating leukoencephalopathy.

We report a case of mild cavitating leukoencephalopathy associated with a homozygous c.755A > G (p.Asp252Gly) NDUFS1 mutation in a 7-year old boy. Biochemical analysis confirmed an isolated reduction in complex I activity. Magnetic resonance imaging of the brain showed a diffuse cystic leukoencephalopathy with the involvement of the corpus callosum and sparing of the gray matter. The clinical course was marked by an acute presentation of neurological deficits at 24 months followed by recurrent episodes of mild neurological deterioration, subsequent remissions, and prolonged periods of stability. This is one of the mildest known clinical presentations of complex I deficiency secondary to mutations in NDUFS1, expanding the clinical spectrum and natural history of this disorder. Consideration of clinical variability needs to be taken into account in patient management and family counseling.

The voltage-gated calcium channel blocker lomerizine is neuroprotective in motor neurons expressing mutant SOD1, but not TDP-43.

Excitotoxicity and disruption of Ca(2+) homeostasis have been implicated in amyotrophic lateral sclerosis (ALS) and limiting Ca(2+) entry is protective in models of ALS caused by mutation of SOD1. Lomerizine, an antagonist of L- and T-type voltage-gated calcium channels and transient receptor potential channel 5 transient receptor potential channels, is well tolerated clinically, making it a potential therapeutic candidate. Lomerizine reduced glutamate excitotoxicity in cultured motor neurons by reducing the accumulation of cytoplasmic Ca(2+) and protected motor neurons against multiple measures of mutant SOD1 toxicity: Ca(2+) overload, impaired mitochondrial trafficking, mitochondrial fragmentation, formation of mutant SOD1 inclusions, and loss of viability. To assess the utility of lomerizine in other forms of ALS, calcium homeostasis was evaluated in culture models of disease because of mutations in the RNA-binding proteins transactive response DNA-binding protein 43 (TDP-43) and Fused in Sarcoma (FUS). Calcium did not play the same role in the toxicity of these mutant proteins as with mutant SOD1 and lomerizine failed to prevent cytoplasmic accumulation of mutant TDP-43, a hallmark of its pathology. These experiments point to differences in the pathogenic pathways between types of ALS and show the utility of primary culture models in comparing those mechanisms and effectiveness of therapeutic strategies.

Spastic paraparesis and marked improvement of leukoencephalopathy in Aicardi-Goutières syndrome.

Aicardi-Goutières syndrome (AGS) is a rare genetic disorder with inflammatory immune-mediated pathogenesis. Disease onset is most commonly marked by recurrent fevers, irritability, and developmental regression in the 1st year of life. A stable phase characterized by severe spastic quadriparesis and cognitive deficit follows. Brain calcifications, leukoencephalopathy, and cerebral atrophy are the radiological hallmarks of AGS and often show progression over time. We present an atypical patient with late-onset AGS characterized by spastic paraparesis and a leukoencephalopathy that markedly improved during follow-up, demonstrating a nonprogressive disease course and the exceptional amelioration of the white matter abnormalities.

Impact of a regionalised clinical cardiac support network on mortality among rural patients with myocardial infarction.

OBJECTIVE: To evaluate the impact of the regionalised Integrated Cardiovascular Clinical Network (ICCNet) on 30-day mortality among patients with myocardial infarction (MI) in an Australian rural setting. DESIGN, SETTING AND PATIENTS: An integrated cardiac support network incorporating standardised risk stratification, point-of-care troponin testing and cardiologist-supported decision making was progressively implemented in non-metropolitan areas of South Australia from 2001 to 2008. Hospital administrative data and statewide death records from 1 July 2001 to 30 June 2010 were used to evaluate outcomes for patients diagnosed with MI in rural and metropolitan hospitals. MAIN OUTCOME MEASURE: Risk-adjusted 30-day mortality. RESULTS: 29 623 independent contiguous episodes of MI were identified. The mean predicted 30-day mortality was lower among rural patients compared with metropolitan patients, while actual mortality rates were higher (30-day mortality: rural, 705/5630 [12.52%] v metropolitan, 2140/23 993 [8.92%]; adjusted odds ratio [OR], 1.46; 95% CI, 1.33-1.60; P< 0.001). After adjustment for temporal improvement in MI outcome, availability of immediate cardiac support was associated with a 22% relative odds reduction in 30-day mortality (OR, 0.78; 95% CI, 0.65-0.93; P= 0.007). A strong association between network support and transfer of patients to metropolitan hospitals was observed (before ICCNet, 1102/2419 [45.56%] v after ICCNet, 2100/3211 [65.4%]; P< 0.001), with lower mortality observed among transferred patients. CONCLUSION: Cardiologist-supported remote risk stratification, management and facilitated access to tertiary hospital-based early invasive management are associated with an improvement in 30-day mortality for patients who initially present to rural hospitals and are diagnosed with MI. These interventions closed the gap in mortality between rural and metropolitan patients in South Australia.

Longitudinal Characterization of the Clinical Course of Intermediate-Severe Salla Disease.

BACKGROUND: Biallelic pathogenic variants in SLC17A5 cause three forms of free sialic acid storage disease categorized based on severity from least to most severe: Salla disease, intermediate-severe Salla disease, and infantile free sialic acid storage disease. Intermediate-severe Salla disease is the most recently described form. Here, we report a longitudinal characterization of intermediate-severe Salla disease progression in two sisters carrying the following biallelic variants in SLC17A5: c.406A>G (p.Lys136Glu) and c.819+1G>A. METHODS: A retrospective review of medical records was performed. A developmental questionnaire was completed to obtain further clinical information. For functional characterization of the predicted splice site variant, RNA was extracted from patient blood samples and sequenced. RESULTS: Disease onset occurred within the first six months of life in both patients. Early childhood development was delayed with achievement of some milestones followed by a developmental plateau in late childhood. After this, both patients began a slow and progressive neurological regression in adolescence. Functional studies confirmed the pathogenicity of the c.819+1G>A variant, resulting in a frameshift and deletion of exon 6. CONCLUSIONS: We present a detailed study describing the clinical course of intermediate-severe Salla disease with over 15 to 20 years of evolution and demonstrate the pathogenicity of the c.819+1G>A splice site variant.

Biallelic pathogenic variants in POLR3D alter tRNA transcription and cause a hypomyelinating leukodystrophy: A case report.

RNA polymerase III-related leukodystrophy (POLR3-related leukodystrophy) is a rare, genetically determined hypomyelinating disease arising from biallelic pathogenic variants in genes encoding subunits of RNA polymerase III (Pol III). Here, we describe the first reported case of POLR3-related leukodystrophy caused by biallelic pathogenic variants in POLR3D, encoding the RPC4 subunit of Pol III. The individual, a female, demonstrated delays in walking and expressive and receptive language as a child and later cognitively plateaued. Additional neurological features included cerebellar signs (e.g., dysarthria, ataxia, and intention tremor) and dysphagia, while non-neurological features included hypodontia, hypogonadotropic hypogonadism, and dysmorphic facial features. Her MRI was notable for diffuse hypomyelination with myelin preservation of early myelinating structures, characteristic of POLR3-related leukodystrophy. Exome sequencing revealed the biallelic variants in POLR3D, a missense variant (c.541C > T, p.P181S) and an intronic splice site variant (c.656-6G > A, p.?). Functional studies of the patient's fibroblasts demonstrated significantly decreased RNA-level expression of POLR3D, along with reduced expression of other Pol III subunit genes. Notably, Pol III transcription was also shown to be aberrant, with a significant decrease in 7SK RNA and several distinct tRNA genes analyzed. Affinity purification coupled to mass spectrometry of the POLR3D p.P181S variant showed normal assembly of Pol III subunits yet altered interaction of Pol III with the PAQosome chaperone complex, indicating the missense variant is likely to alter complex maturation. This work identifies biallelic pathogenic variants in POLR3D as a novel genetic cause of POLR3-related leukodystrophy, expanding the molecular spectrum associated with this disease, and proposes altered tRNA homeostasis as a factor in the underlying biology of this hypomyelinating disorder.

Hypomyelination caused by a novel homozygous pathogenic variant in FOLR1: complete clinical and radiological recovery with oral folinic acid therapy and review of the literature.

BACKGROUND: Neurodegeneration due to cerebral folate transport deficiency is a rare autosomal recessive disorder caused by biallelic pathogenic variants in FOLR1. Onset typically occurs in late infancy and is characterized by psychomotor regression, epilepsy, and a hypomyelinating leukodystrophy on magnetic resonance imaging. If left untreated, progressive neurodegeneration occurs. However, early treatment with folinic acid has been shown to stabilize or reverse neurological features. Approximately thirty patients have been described worldwide. Here, we report the first two cases with genetically proven cerebral folate transport deficiency from South-Eastern Europe, describe the effect of oral folinic acid therapy on clinical and neuroradiological features and review the literature. RESULTS: Two siblings presented in childhood with clinical and radiological findings consistent with a hypomyelinating leukodystrophy. Exome sequencing revealed a novel homozygous pathogenic variant in FOLR1 (c.465_466delinsTG; p.W156G), confirming the diagnosis of neurodegeneration due to cerebral folate transport deficiency. Folinic acid treatment was promptly initiated in both patients. The younger sibling was treated early in disease course at 2 years of age, and demonstrated complete recovery in clinical and MRI features. The older sibling, who was 8 years of age at the time of diagnosis and treatment, demonstrated partial but substantial improvements. CONCLUSION: We present the first account in the literature that early treatment initiation with oral folinic acid alone can result in complete neurological recovery of both clinical and radiological abnormalities in neurodegeneration due to cerebral folate deficiency. Moreover, through the report of these patients along with review of the literature, we provide information about the natural history of the disease with comparison of treatment effects at different stages of disease progression. This report also reinforces the importance of universal access to genetic testing to ensure prompt diagnoses for treatable disorders.

Cysteine-rich peptides: From bioactivity to bioinsecticide applications.

Greater levels of insect resistance and constraints on the use of current pesticides have recently led to increased crop losses in agricultural production. Further, the health and environmental impacts of pesticides now restrict their application. Biologics based on peptides are gaining popularity as efficient crop protection agents with low environmental toxicity. Cysteine-rich peptides (whether originated from venoms or plant defense substances) are chemically stable and effective as insecticides in agricultural applications. Cysteine-rich peptides fulfill the stability and efficacy requirements for commercial uses and provide an environmentally benign alternative to small-molecule insecticides. In this article, cysteine-rich insecticidal peptide classes identified from plants and venoms will be highlighted, focusing on their structural stability, bioactivity and production.