Neuropsychological profile in tuberous sclerosis complex: a study of clinical and cognitive variables in a cohort from Brazil.

Background:  Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder with a wide clinical, cognitive, and behavioral expressivity.

Objective:  To assess the neuropsychological profile of individuals clinically diagnosed with TSC and the factors that could significantly impact their cognitive development.

Methods:  A total of 62 individuals with ages ranging from 3 to 38 years were followed up in a tertiary attention hospital in Southern Brazil, and they were assessed using a standard battery and the Vineland Adaptive Behavior Scales, when intellectual disability was observed.

Neurological, cognitive and learning evaluation of students who were born preterm.

Objective: To evaluate the cognitive and academic profile of preterm newborns at school age and to determine the factors related to prematurity and sociodemographic profile that influence these results.

Methods: Patients aged 6-14 years old that were assisted in the preterm follow-up clinic were recruited. The cognitive, academic, and neurological capacities were accessed through a detailed evaluation with a child neurologist, a neuropsychologist and a psychopedagogue.

The First Unprovoked Seizure in Typically Developing Children: A Real-Life Setting in Southern Brazil.

Aim: To describe the first unprovoked seizure in typically developing children, its clinical characteristics, recurrence rate, and possible risk factors in a real-life setting in Southern Brazil.

Method: In this retrospective cohort study, medical records of typically developing children aged 28 days to 14 years who had a first unprovoked seizure in a single tertiary care center were reviewed, in a 10-year period (2006-2016).

Results: Seventy-four children were included, 41 males and 33 females.

An intact Mcm10 coiled-coil interaction surface is important for origin melting, helicase assembly and the recruitment of Pol-α to Mcm2-7.

Mcm10 is an essential eukaryotic factor required for DNA replication. The replication fork helicase is composed of Cdc45, Mcm2-7 and GINS (CMG). DDK is an S-phase-specific kinase required for replication initiation, and the DNA primase-polymerase in eukaryotes is pol α.

Dpb11 may function with RPA and DNA to initiate DNA replication.

Dpb11 is required for the initiation of DNA replication in budding yeast. We found that Dpb11 binds tightly to single-stranded DNA (ssDNA) or branched DNA structures, while its human homolog, TopBP1, binds tightly to branched-DNA structures. We also found that Dpb11 binds stably to CDK-phosphorylated RPA, the eukaryotic ssDNA binding protein, in the presence of branched DNA.

Eukaryotic Replicative Helicase Subunit Interaction with DNA and Its Role in DNA Replication.

The replicative helicase unwinds parental double-stranded DNA at a replication fork to provide single-stranded DNA templates for the replicative polymerases. In eukaryotes, the replicative helicase is composed of the Cdc45 protein, the heterohexameric ring-shaped Mcm2-7 complex, and the tetrameric GINS complex (CMG). The CMG proteins bind directly to DNA, as demonstrated by experiments with purified proteins.

Origin DNA Melting-An Essential Process with Divergent Mechanisms.

Origin DNA melting is an essential process in the various domains of life. The replication fork helicase unwinds DNA ahead of the replication fork, providing single-stranded DNA templates for the replicative polymerases. The replication fork helicase is a ring shaped-assembly that unwinds DNA by a steric exclusion mechanism in most DNA replication systems.

A Positive Amplification Mechanism Involving a Kinase and Replication Initiation Factor Helps Assemble the Replication Fork Helicase.

The assembly of the replication fork helicase during S phase is key to the initiation of DNA replication in eukaryotic cells. One step in this assembly in budding yeast is the association of Cdc45 with the Mcm2-7 heterohexameric ATPase, and a second step is the assembly of the tetrameric GINS (G-chi-ii-an) complex with Mcm2-7. Dbf4-dependent kinase (DDK) and S-phase cyclin-dependent kinase (S-CDK) are two S phase-specific kinases that phosphorylate replication proteins during S phase, and Dpb11, Sld2, Sld3, Pol ϵ, and Mcm10 are factors that are also required for replication initiation.

Insights into the Initiation of Eukaryotic DNA Replication.

The initiation of DNA replication is a highly regulated event in eukaryotic cells to ensure that the entire genome is copied once and only once during S phase. The primary target of cellular regulation of eukaryotic DNA replication initiation is the assembly and activation of the replication fork helicase, the 11-subunit assembly that unwinds DNA at a replication fork. The replication fork helicase, called CMG for Cdc45-Mcm2-7, and GINS, assembles in S phase from the constituent Cdc45, Mcm2-7, and GINS proteins.

Mcm10 coordinates the timely assembly and activation of the replication fork helicase.

Mcm10 is an essential replication factor that is required for DNA replication in eukaryotes. Two key steps in the initiation of DNA replication are the assembly and activation of Cdc45-Mcm2-7-GINS (CMG) replicative helicase. However, it is not known what coordinates helicase assembly with helicase activation.

The Replication Initiation Protein Sld3/Treslin Orchestrates the Assembly of the Replication Fork Helicase during S Phase.

The initiation of DNA replication is a highly regulated process in eukaryotic cells, and central to the process of initiation is the assembly and activation of the replication fork helicase. The replication fork helicase is comprised of CMG (Cdc45, Mcm2-7, and GINS) in eukaryotic cells, and the mechanism underlying assembly of the CMG during S phase was studied in this article. We identified a point mutation of Sld3 that is specifically defective for Mcm3 and Mcm5 interaction (sld3-m10), and also identified a point mutation of Sld3 that is specifically defective for single-stranded DNA (ssDNA) interaction (sld3-m9).

Conserved mechanism for coordinating replication fork helicase assembly with phosphorylation of the helicase.

Dbf4-dependent kinase (DDK) phosphorylates minichromosome maintenance 2 (Mcm2) during S phase in yeast, and Sld3 recruits cell division cycle 45 (Cdc45) to minichromosome maintenance 2-7 (Mcm2-7). We show here DDK-phosphoryled Mcm2 preferentially interacts with Cdc45 in vivo, and that Sld3 stimulates DDK phosphorylation of Mcm2 by 11-fold. We identified a mutation of the replication initiation factor Sld3, Sld3-m16, that is specifically defective in stimulating DDK phosphorylation of Mcm2.

Dpb11 protein helps control assembly of the Cdc45·Mcm2-7·GINS replication fork helicase.

Dpb11 is required for the initiation of DNA replication in budding yeast. Dpb11 binds to S-phase cyclin-dependent kinase-phosphorylated Sld2 and Sld3 to form a ternary complex during S phase. The replication fork helicase in eukaryotes is composed of Cdc45, Mcm2-7, and GINS.

Accuracy of optic nerve sheath diameter measurement by emergency physicians using bedside ultrasound.

Background: Ultrasound (US) measurement of the optic nerve sheath diameter (ONSD) has been utilized as an indirect assessment of intracranial pressure. It is usually performed by trained ultrasonographers.

Objectives: To evaluate whether or not emergency physicians (EP) are capable of measuring the ONSD accurately by US.

The Dbf4-Cdc7 kinase promotes Mcm2-7 ring opening to allow for single-stranded DNA extrusion and helicase assembly.

The replication fork helicase in eukaryotes is composed of Cdc45, Mcm2-7, and GINS (CMG). The Dbf4-Cdc7 kinase phosphorylates Mcm2 in vitro, but the in vivo role for Dbf4-Cdc7 phosphorylation of Mcm2 is unclear. We find that budding yeast Dbf4-Cdc7 phosphorylates Mcm2 in vivo under normal conditions during S phase.

Side-to-side growth discrepancies in children with hemiplegic cerebral palsy: association with function, activity and social participation.

Objective: Evaluate side-to-side discrepancies in children with hemiplegic cerebral palsy (HCP), and investigate associations of these discrepancies with patients' age at initiation of physical therapy, motor and cognitive function, and degree of activities and social participation.

Method: We obtained eight side-to-side measurements from 24 HCP children with mean age 49.3±5.

Niemann-Pick disease type C: a case series of Brazilian patients.

Unlabelled: The aim of the study was to analyze a series of Brazilian patients with Niemann-Pick disease type C (NP-C).

Method: Correlations between clinical findings, laboratory data, molecular findings and treatment response are presented.

Result: The sample consisted of 5 patients aged 8 to 26 years.

The replication initiation protein Sld2 regulates helicase assembly.

Assembly of the Cdc45-Mcm2-7-GINS (CMG) replicative helicase complex must be regulated to ensure that DNA unwinding is coupled with DNA synthesis. Sld2 is required for the initiation of DNA replication in budding yeast. We identified a mutant of Sld2, Sld2-m1,4, that is specifically defective in Mcm2-7 binding.

Correlation of optic nerve sheath diameter measurements by computed tomography and magnetic resonance imaging.

Background: Traditionally, intracranial pressure is measured by direct ventriculostomy, which is invasive. Noninvasive measures such as bedside ultrasound and magnetic resonance imaging have been advocated and utilized recently to assess the intracranial pressure. The role of this study is to determine the degree of agreement between measurements of the optic nerve sheath diameter by computed tomography (CT) and magnetic resonance imaging (MRI).

Effects of early spasticity treatment on children with hemiplegic cerebral palsy: a preliminary study.

Objective: To compare motor and functional performance of two groups of children with hemiplegic cerebral palsy (HCP). Only the study group (SG) received early treatment of spasticity with botulinum neurotoxin type A (BXT-A).

Methods: Gross Motor Function Measure (GMFM), functional performance (Pediatric Evaluation of Disability Inventory - PEDI), range of movement, gait pattern (Physician Rating Scale - PRS) and the speed of hand movements were considered.

Cdc45 protein-single-stranded DNA interaction is important for stalling the helicase during replication stress.

Replicative polymerase stalling is coordinated with replicative helicase stalling in eukaryotes, but the mechanism underlying this coordination is not known. Cdc45 activates the Mcm2-7 helicase. We report here that Cdc45 from budding yeast binds tightly to long (≥ 40 nucleotides) genomic single-stranded DNA (ssDNA) and that 60mer ssDNA specifically disrupts the interaction between Cdc45 and Mcm2-7.