Manuel Recio Rodríguez

MR Imaging of Thoracic Abnormalities in the Fetus

In recent years, with the development of ultrafast sequences, magnetic resonance (MR) imaging has been established as a valuable diagnostic modality complementary to ultrasonography (US). MR imaging offers several technical advantages over US, including a larger field of view, fewer limitations due to maternal habitus, and the ability to visualize fetal anatomy regardless of fetal presentation. The authors discuss the most frequently found thoracic abnormalities, including congenital diaphragmatic hernia, congenital cystic adenomatoid malformation, bronchopulmonary sequestration, bronchogenic cyst, congenital high airway obstruction syndrome, and bronchial obstruction by a mucus plug, specifically with respect to the effect of fetal MR imaging on diagnosis and treatment. MR imaging can assist in establishing the prognosis and in perinatal management, especially in the case of congenital diaphragmatic hernia, which is the most common indication for thoracic MR imaging. MR imaging can demonstrate hernial contents and quantify lung volume better than US, allowing the prognosis to be determined and postpartum extracorporeal membrane oxygenation needs to be estimated. MR imaging can also be used to distinguish different types of cystic adenomatoid malformations, identify the anomalous vessels of pulmonary sequestration, and assess the functional effects of bronchogenic cysts. Balanced sequences (steady-state free precession sequences) allow performance of unenhanced thoracic vascular studies, which are useful in the diagnosis of intralobar or extralobar sequestration. In summary, fetal MR imaging can provide additional data useful in establishing prognosis and in perinatal management of thoracic malformations.

Spontaneous Skull Base Meningoencephaloceles and Cerebrospinal Fluid Fistulas

Cerebrospinal fluid (CSF) fistulas are characterized by the egress of CSF from the intracranial cavity through an osteodural disruption between the subarachnoid space and a pneumatized structure within the skull base. Depending on the cause, CSF fistulas are classified as acquired or congenital, and acquired fistulas are further classified as traumatic, nontraumatic, or spontaneous. Spontaneous CSF fistulas are considered to result from a multifactorial process and have been postulated to represent a variant of idiopathic intracranial hypertension. However, an anatomic predisposition involving thinning of the cranial base, such as pneumatization of the sinus walls, must also be present. This process creates areas of structural weakness that act as potential pathways for CSF leaks, which most commonly occur in the ethmoid roof, sphenoid sinus, and temporal bone. Because CSF leaks may be overlooked, a result of their asymptomatic or subtle, intermittent course, a high level of suspicion is crucial in making an early diagnosis. However, CSF fistulas may be well seen at computed tomography (CT), which depicts bone defects, and magnetic resonance cisternography, which reveals the contents of herniated tissue. Knowledge of the location and size of the bone defect and herniated contents is crucial for the selection of surgical approach and grafting material.

Cortical thickness differences in the prefrontal cortex in children and adolescents with ADHD in relation to dopamine transporter (DAT1) genotype

Several lines of evidence suggest that the dopamine transporter gene (DAT1) plays a crucial role in attention deficit hyperactivity disorder (ADHD). Concretely, recent data indicate that the 10-repeat (10R) DAT1 allele may mediate neuropsychological functioning, response to methylphenidate, and even brain function and structure in children with ADHD. This study aimed to investigate the influence of 10R DAT1 on thickness of the prefrontal cortex in children and adolescents with ADHD. To this end, brain magnetic resonance images were acquired from 33 patients with homozygosity for the 10R allele and 30 patients with a single copy or no copy of the allele. The prefrontal cortex of each MRI scan was automatically parceled into regions of interest (ROIs) based on Brodmann areas (BA). The two groups were matched for age, gender, IQ, ADHD subtype, symptom severity, comorbidity and medication status. However, patients with two copies of the 10R allele exhibited significantly decreased cortical thickness in right BA 46 relative to patients with one or fewer copies of the allele. No other prefrontal ROI differed significantly between the two groups. Present findings suggest that cortical thickness of right lateral prefrontal cortex (BA 46) is influenced by the presence of the DAT1 10 repeat allele in children and adolescents with ADHD.

Cingulate Cortical Thickness and Dopamine Transporter (DAT1) Genotype in Children and Adolescents With ADHD

Objective: This study aimed to examine the influence of dopamine transporter gene (DAT1) 3’UTR genotype on cingulate cortical thickness in a large sample of children and adolescents with ADHD. Method: Brain MRIs were acquired from 46 ADHD patients with homozygosity for the 10-repeat allele and 52 ADHD patients with a single copy or no copy of the allele. The cingulate cortex of each MRI scan was automatically parceled into sulci and gyri as well as into Brodmann areas (BA). Results: There were no group differences in age, gender, full-scale intelligence quotient, symptom severity, treatment status, comorbidity, or mean overall cortical thickness. Sulcus/gyrus- and BA-based analyses revealed that patients homozygous for the 10-repeat allele showed significantly greater thickness in right cingulate gyrus and right BA 24 compared with 9-repeat carriers. Conclusion: These findings suggest that thickness of cingulate cortex is influenced by the presence of the 10-repeat allele in ADHD.

Catalytic Nitrene Transfer To Alkynes: A Novel and Versatile Route for the Synthesis of Sulfinamides and Isothiazoles

A novel transformation is reported for the reaction of terminal or internal alkynes with the nitrene precursor PhI=NTs (Ts=p-toluenesulfonyl) in the presence of catalytic amounts of TpBr3 Cu(NCMe) (TpBr3 =hydrotris(3,4,5-tribromo-pyrazolylborate). Two products containing an imine functionality have been isolated from the reaction mixtures, identified as sulfinamides and isothiazoles. The former correspond to the formal reduction of the sulfone group into sulfoxide, whereas the latter involves the insertion of an alkyne carbon atom into the aromatic ring of the N-tosyl moiety.

Cortical thickness at the time of the initial attack in two patients with paediatric relapsing–remitting multiple sclerosis

BACKGROUND Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system with a low incidence in the paediatric population; cortical atrophy is often striking, even in the early stages of the disease. Evidence of cortical thinning in childhood MS is scant. AIMS This study aimed to assess cortical thickness in paediatric patients during the initial attack of remitting-relapsing MS. METHODS We report two cases of remitting-relapsing MS, with initial attacks at 12 and 16 years of age. We analysed brain cortical thickness (CTh) in these patients and compared these data to the CTh of a control group comprised of six 12-year-old females and six 16-year-old males. RESULTS Both cases exhibited a total brain CTh significantly below that of the control group. This difference was also observed when analysing the CTh of all lobes except the left parietal lobe in one of the cases. CONCLUSIONS Cortical atrophy is already present at the time of onset of MS. Studies with larger patient populations that have a more homogenous clinical presentation could identify the time of onset of cortical atrophy and use this parameter as a prognostic and/or treatment marker of MS.

Trispyrazolylborate Ligands Supported on Vinylic Addition Polynorbornenes and their Copper Derivatives as Recyclable Catalysts

Polynorbornenes prepared by vinyl addition polymerization and bearing pendant alkenyl groups serve as skeletons to support trispyrazolylborate ligands (Tpx ) built at those alkenyl sites. Reaction with CuI in acetonitrile led to VA-PNB-Tpx Cu(NCMe) (VA-PBN=vinyl addition polynorbornene) with a 0.8-1.4 mmol incorporation of Cu per gram of polymer. The presence of tetracoordinated copper(I) ions was been assessed by FTIR studies on the corresponding VA-PNB-Tpx Cu(CO) adducts, in agreement with those on discrete Tpx Cu(CO). The new materials were employed as heterogeneous catalysts in several carbene- and nitrene-transfer reactions, showing a behavior similar to that of the homogeneous counterparts but also being recycled several times maintaining a high degree of activity and selectivity. This is the first example of supported Tpx ligands onto polymeric supports with catalytic applications.