RNA methyltransferase SPOUT1/CENP-32 links mitotic spindle organization with the neurodevelopmental disorder SpADMiSS.

SPOUT1/CENP-32 encodes a putative SPOUT RNA methyltransferase previously identified as a mitotic chromosome associated protein. SPOUT1/CENP-32 depletion leads to centrosome detachment from the spindle poles and chromosome misalignment. Aided by gene matching platforms, we identified 24 individuals with neurodevelopmental delays from 18 families with bi-allelic variants in SPOUT1/CENP-32 detected by exome/genome sequencing. Zebrafish spout1/cenp-32 mutants showed reduction in larval head size with concomitant apoptosis likely associated with altered cell cycle progression. In vivo complementation assays in zebrafish indicated that SPOUT1/CENP-32 missense variants identified in humans are pathogenic. Crystal structure analysis of SPOUT1/CENP-32 revealed that most disease-associated missense variants mapped to the catalytic domain. Additionally, SPOUT1/CENP-32 recurrent missense variants had reduced methyltransferase activity in vitro and compromised centrosome tethering to the spindle poles in human cells. Thus, SPOUT1/CENP-32 pathogenic variants cause an autosomal recessive neurodevelopmental disorder: SpADMiSS ( SPOUT1 Associated Development delay Microcephaly Seizures Short stature) underpinned by mitotic spindle organization defects and consequent chromosome segregation errors.

Clinical and Molecular Diagnosis of Osteocraniostenosis in Fetuses and Newborns: Prenatal Ultrasound, Clinical, Radiological and Pathological Features.

Osteocraniostenosis (OCS, OMIM #602361) is a severe, usually lethal condition characterized by gracile bones with thin diaphyses, a cloverleaf-shaped skull and splenic hypo/aplasia. The condition is caused by heterozygous mutations in the FAM111A gene and is allelic to the non-lethal, dominant disorder Kenny-Caffey syndrome (KCS, OMIM #127000). Here we report two new cases of OCS, including one with a detailed pathological examination. We review the main diagnostic signs of OCS both before and after birth based on our observations and on the literature. We then review the current knowledge on the mutational spectrum of FAM111A associated with either OCS or KCS, including three novel variants, both from one of the OCS fetuses described here, and from further cases diagnosed at our centers. This report refines the previous knowledge on OCS and expands the mutational spectrum that results in either OCS or KCS.

Rapid exome sequencing in PICU patients with new-onset metabolic or neurological disorders.

BACKGROUND: Genomic assessment previously took months to result and was unable to impact clinical care in the pediatric intensive care unit (PICU). The advent of rapid exome sequencing potentially changes this. We investigated the impact of rapid exome sequencing in a pilot study on pediatric patients admitted to a single PICU with new-onset metabolic/neurologic disease. METHODS: Rapid exome sequencing (7 days to verbal result) was performed on (n = 10) PICU patients age < 6 years admitted with new-onset metabolic/neurologic disease. The primary outcome of interest was inpatient LOS, which served as a proxy for inpatient cost. RESULTS: A significant reduction in median LOS was identified when comparing PICU patients who underwent rapid exome sequencing to historical controls. From those patients who underwent rapid sequencing, five had likely pathogenic variants. In three cases with diagnostic genetic results, there was a modification to clinical care attributable to information provided by exome sequencing. CONCLUSIONS: This pilot study demonstrates that rapid exome sequencing is feasible to do in the PICU, that genetic results can be returned quickly enough to impact critical care decision-making and management. In a select population of PICU patients, this technology may contribute to a decrease in hospital length of stay. IMPACT: Ten prospectively enrolled PICU patients with defined clinical criteria and their parents underwent rapid exome sequencing. Fifty percent received a genetic diagnosis, and medical management was affected for 60% of those patients. Median hospital LOS was significantly decreased in this selective subset of PICU patients. Genetic disorders and congenital anomalies are a leading cause of pediatric mortality. Genomic assessment previously took weeks to months for results and was therefore unable to acutely impact clinical care in the pediatric intensive care unit (PICU). The recent advent of rapid exome sequencing changes this in selected patients. Rapid exome sequencing is feasible to do in a PICU. Genetic results can be returned quickly enough to impact critical care decision-making. When done in a carefully selected subset of pediatric patients, rapid exome sequencing can potentially decrease hospital LOS.

Histomorphologic effects of Bacillus clausii spores in enteropathogenic E. coli O127:H21-infected mice: A pilot study

OBJECTIVE: The study aimed to determine the basic histomorphologic effects of Bacillus clausii (B. clausii) spores in enteropathogenic Escherichia coli (E. coli) O127:H21-infected mice by evaluating the spleen, mesenteric lymph nodes, and intestinal mucosa. METHODS: The study involved 46 apparently healthy Balb/c mice (Mus musculus) which were acclimatized for 19 days prior to any intervention. Sixteen mice were used to determine the sublethal dose of E. coli, which was performed by administering serially-diluted solutions and subsequent generation of a standard curve. From the remaining 30 mice, ten served as normal controls while the remaining 20 were randomized to receive either B. clausii or placebo of sterile water for a week. All mice were then challenged with E. coli for another week and euthanized, and the spleen, mesenteric lymph nodes, and small intestine harvested and examined microscopically. All study personnel were blinded of the treatment assignments. RESULTS: Histologic evaluation of the small intestine in E. coli only-fed mice exhibited prominent attachment effacement lesions, with severely denuded mucosa, lymphocytic infiltration, and debris in the intestinal lumen. However, mice given B. clausii prior to E. coli infection displayed only minimal mucosal damage with less sloughing of villus tips, plus increased mucus-secreting goblet cells. In the spleen, E. coli only-fed mice showed moderate to severe lymphoid hyperplasia with blurred boundaries between red and white pulp. In contrast, mice which received B. clausii prior to E. coli infection had only mild degrees of lymphoid hyperplasia. Similar findings were seen in the mesenteric lymph nodes where E. coli only-fed mice showed moderate to severe lymphoid hyperplasia while those given B. clausii prior to E. coli infection merely had mild lymphoid hyperplasia. CONCLUSION: B. clausii exerts a potential protective and immunomodulatory action in E. coli O127:H21-infected mice based on histomorphologic effects. However, additional studies are needed to fully characterize these mechanisms.mice based on histomorphologic effects.