Neocerebellar Crus I Abnormalities Associated with a Speech and Language Disorder Due to a Mutation in FOXP2.

Bilateral volume reduction in the caudate nucleus has been established as a prominent brain abnormality associated with a FOXP2 mutation in affected members of the 'KE family', who present with developmental orofacial and verbal dyspraxia in conjunction with pervasive language deficits. Despite the gene's early and prominent expression in the cerebellum and the evidence for reciprocal cerebellum-basal ganglia connectivity, very little is known about cerebellar abnormalities in affected KE members. Using cerebellum-specific voxel-based morphometry (VBM) and volumetry, we provide converging evidence from subsets of affected KE members scanned at three time points for grey matter (GM) volume reduction bilaterally in neocerebellar lobule VIIa Crus I compared with unaffected members and unrelated controls. We also show that right Crus I volume correlates with left and total caudate nucleus volumes in affected KE members, and that right and total Crus I volumes predict the performance of affected members in non-word repetition and non-verbal orofacial praxis. Crus I also shows bilateral hypo-activation in functional MRI in the affected KE members relative to controls during non-word repetition. The association of Crus I with key aspects of the behavioural phenotype of this FOXP2 point mutation is consistent with recent evidence of cerebellar involvement in complex motor sequencing. For the first time, specific cerebello-basal ganglia loops are implicated in the execution of complex oromotor sequences needed for human speech.

Gene expression profiling in subcutaneous, visceral and epigastric adipose tissues of patients with extreme obesity.

OBJECTIVE: The goal of the present study was to identify differences in gene expression between SAT, VAT and EAT depots in Class III severely obese individuals. DESIGN: Human subcutaneous (SAT) and visceral (VAT) adipose tissues exhibit differential gene expression profiles. There is little information, however, about the other proximal white adipose tissue, epigastric (EAT), in terms of its function and contribution to metabolism. SUBJECTS AND METHODS: Using RNA from adipose biospecimens obtained from Class III severely obese patients undergoing open Roux-en-Y gastric bypass surgery, we compared gene expression profiles between SAT, VAT and EAT, using microarrays validated by real-time quantitative PCR. RESULTS: The three depots were found to share 1907 genes. VAT had the greatest number of genes (66) expressed exclusively in this depot, followed by SAT (23), and then EAT (14). Moreover, VAT shared more genes with EAT (65) than with SAT (38). Further analyses using ratios of SAT/EAT, VAT/EAT and SAT/VAT identified specific as well as overlapping networks and pathways of genes representing dermatological diseases, inflammation, cell cycle and growth, cancer and development. Targeted analysis of genes, having a role in adipose tissue development and function, revealed that Peroxisome proliferator-activated receptor Gamma Coactivator 1-alpha (PGC1-α) that regulates the precursor of the hormone Irisin (FNCD5) were abundantly expressed in all three fat depots, along with fibroblast growth factors (FGF) FGF1, FGF7 and FGF10, whereas, FGF19 and FGF21 were undetectable. CONCLUSIONS: These data indicate that EAT has more in common with VAT, suggesting similar metabolic potential. The human epigastric adipose depot could have a significant functional role in metabolic diseases and should be further investigated.

Non-invasive cerebellar stimulation--a consensus paper.

The field of neurostimulation of the cerebellum either with transcranial magnetic stimulation (TMS; single pulse or repetitive (rTMS)) or transcranial direct current stimulation (tDCS; anodal or cathodal) is gaining popularity in the scientific community, in particular because these stimulation techniques are non-invasive and provide novel information on cerebellar functions. There is a consensus amongst the panel of experts that both TMS and tDCS can effectively influence cerebellar functions, not only in the motor domain, with effects on visually guided tracking tasks, motor surround inhibition, motor adaptation and learning, but also for the cognitive and affective operations handled by the cerebro-cerebellar circuits. Verbal working memory, semantic associations and predictive language processing are amongst these operations. Both TMS and tDCS modulate the connectivity between the cerebellum and the primary motor cortex, tuning cerebellar excitability. Cerebellar TMS is an effective and valuable method to evaluate the cerebello-thalamo-cortical loop functions and for the study of the pathophysiology of ataxia. In most circumstances, DCS induces a polarity-dependent site-specific modulation of cerebellar activity. Paired associative stimulation of the cerebello-dentato-thalamo-M1 pathway can induce bidirectional long-term spike-timing-dependent plasticity-like changes of corticospinal excitability. However, the panel of experts considers that several important issues still remain unresolved and require further research. In particular, the role of TMS in promoting cerebellar plasticity is not established. Moreover, the exact positioning of electrode stimulation and the duration of the after effects of tDCS remain unclear. Future studies are required to better define how DCS over particular regions of the cerebellum affects individual cerebellar symptoms, given the topographical organization of cerebellar symptoms. The long-term neural consequences of non-invasive cerebellar modulation are also unclear. Although there is an agreement that the clinical applications in cerebellar disorders are likely numerous, it is emphasized that rigorous large-scale clinical trials are missing. Further studies should be encouraged to better clarify the role of using non-invasive neurostimulation techniques over the cerebellum in motor, cognitive and psychiatric rehabilitation strategies.

T2 mapping of lumbar intervertebral disc: quantitative evaluation of degeneration in relation to Pfirrmann grading system and a template for intervertebral disc segmentation.

Background: To assess the feasibility of using T2 relaxation time mapping at 3 Tesla (3T) magnetic resonance imaging (MRI) for detection and classification of lumbar intervertebral disc degeneration, introducing an objective model of disc segmentation for accurate disc assessment. Materials and Methods: The present study is a single-center prospective evaluation including 185 lumbar intervertebral discs from a cohort of 37 patients with chronic lower back pain. For the quantitative classification of disc degeneration, three regions of interest (ROIs) were drawn on T2 maps, and the Pfirrmann grading system was used for qualitative assessment. Intergroup evaluation was performed with paired t-tests. Analysis of variance (ANOVA) was used to compare the mean value of T2 mapping, and Tukey's multiple comparison test was applied to determine differences in mean values of T2 mapping among the Pfirrmann categories. Results: The ANOVA test analysis of ROIs showed that there is a statistically significant difference (p <0.001) among average T2 relaxation time mapping values in different Pfirrmann score groups, and Tukey's multiple comparison tests revealed that mean values of T2 map among the different grades of Pfirrmann differ from the rest (p <0.001) except grade V. Paired t-tests revealed significant differences in mean values of T2 map between different ROIs. Conclusion: This study showed that quantitative T2 mapping of the lumbar intervertebral discs at 3T MRI may overcome the subjective element of qualitative classification systems for degenerative intervertebral disc disease. Also, a new template of disc segmentation with more ROIs would be more sensitive for the assessment of disc degeneration. HIPPOKRATIA 2023, 27 (2):75-81.

Haplotype diversity and linkage disequilibrium at human G6PD: recent origin of alleles that confer malarial resistance.

The frequencies of low-activity alleles of glucose-6-phosphate dehydrogenase in humans are highly correlated with the prevalence of malaria. These "deficiency" alleles are thought to provide reduced risk from infection by the Plasmodium parasite and are maintained at high frequency despite the hemopathologies that they cause. Haplotype analysis of "A-" and "Med" mutations at this locus indicates that they have evolved independently and have increased in frequency at a rate that is too rapid to be explained by random genetic drift. Statistical modeling indicates that the A- allele arose within the past 3840 to 11,760 years and the Med allele arose within the past 1600 to 6640 years. These results support the hypothesis that malaria has had a major impact on humans only since the introduction of agriculture within the past 10,000 years and provide a striking example of the signature of selection on the human genome.

Chimera patterns and subthreshold oscillations in two-dimensional networks of fractally coupled leaky integrate-and-fire neurons.

We discuss the effects that fractal coupling induces on chimera states in a network of leaky integrate-and-fire (LIF) oscillators arranged in a two-dimensional toroidal geometry. We provide evidence that the introduction of a hierarchical coupling topology in the form of a Sierpinski carpet gives rise to complex spatial structures such as multiple spots, stripe-and-grid chimeras, as well as traveling waves and subthreshold oscillations. Unlike in the case of typical nonlocal connectivity, when tuning the coupling strength to small positive values a spot chimera is formed with internal structure reminiscent of the fractal connectivity scheme. This is in line with previous results for one-dimensional networks, where hierarchical connectivity also induces chimeras with stratified spatial arrangements. In the case of negative coupling, cooperative effects produce subthreshold oscillating regions with traveling active islands crossing through them. Subthreshold oscillations and traveling waves are frequently reported in biological neural network experiments.

Effects of mutations in the human uncoupling protein 3 gene on the respiratory quotient and fat oxidation in severe obesity and type 2 diabetes.

Human uncoupling protein 3 (UCP3) is a mitochondrial transmembrane carrier that uncouples oxidative ATP phosphorylation. With the capacity to participate in thermogenesis and energy balance, UCP3 is an important obesity candidate gene. A missense polymorphism in exon 3 (V102I) was identified in an obese and diabetic proband. A mutation introducing a stop codon in exon 4 (R143X) and a terminal polymorphism in the splice donor junction of exon 6 were also identified in a compound heterozygote that was morbidly obese and diabetic. Allele frequencies of the exon 3 and exon 6 splice junction polymorphisms were determined and found to be similar in Gullah-speaking African Americans and the Mende tribe of Sierra Leone, but absent in Caucasians. Moreover, in exon 6-splice donor heterozygotes, basal fat oxidation rates were reduced by 50%, and the respiratory quotient was markedly increased compared with wild-type individuals, implicating a role for UCP3 in metabolic fuel partitioning.

A rare mutation in AgRP, +79G>A, affects promoter activity.

The agouti-related protein is a powerful orexigenic peptide. A rare mutation, +79G>A, was identified in its minimal promoter in two white carriers. Comparison of the 45-year-old male proband, who was also a carrier of the common Ala67Thr polymorphism, with an age- and weight-matching wild-type population showed marginal differences for resting metabolic rate (RMR) and body mass index. The second carrier however was an obese 57-year-old female with reduced RMR. Functional analysis in hypothalamus- and periphery-derived cell lines showed reduced promoter activity for the +79A allele in the adrenocortical cells only, suggesting that it could affect the peripheral expression levels of AgRP. The +79G>A mutation could predispose to body weight gain (as suggested by the phenotype of the second carrier), but it could only affect the proband at an older age as he may be protected by the Ala67Thr polymorphism that is associated with resistance to late-onset fatness.

Source apportionment of PM10 and PM2.5 in major urban Greek agglomerations using a hybrid source-receptor modeling process.

A hybrid source-receptor modeling process was assembled, to apportion and infer source locations of PM10 and PM2.5 in three heavily-impacted urban areas of Greece, during the warm period of 2011, and the cold period of 2012. The assembled process involved application of an advanced computational procedure, the so-called Robotic Chemical Mass Balance (RCMB) model. Source locations were inferred using two well-established probability functions: (a) the Conditional Probability Function (CPF), to correlate the output of RCMB with local wind directional data, and (b) the Potential Source Contribution Function (PSCF), to correlate the output of RCMB with 72h air-mass back-trajectories, arriving at the receptor sites, during sampling. Regarding CPF, a higher-level conditional probability function was defined as well, from the common locus of CPF sectors derived for neighboring receptor sites. With respect to PSCF, a non-parametric bootstrapping method was applied to discriminate the statistically significant values. RCMB modeling showed that resuspended dust is actually one of the main barriers for attaining the European Union (EU) limit values in Mediterranean urban agglomerations, where the drier climate favors build-up. The shift in the energy mix of Greece (caused by the economic recession) was also evidenced, since biomass burning was found to contribute more significantly to the sampling sites belonging to the coldest climatic zone, particularly during the cold period. The CPF analysis showed that short-range transport of anthropogenic emissions from urban traffic to urban background sites was very likely to have occurred, within all the examined urban agglomerations. The PSCF analysis confirmed that long-range transport of primary and/or secondary aerosols may indeed be possible, even from distances over 1000km away from study areas.

Interphase in situ hybridization reveals minimal residual disease in early remission and return of the diagnostic clone in karyotypically normal relapse of acute lymphoblastic leukemia.

Early clinical remission of acute lymphoblastic leukemia (ALL) was examined by fluorescence in situ hybridization (FISH) in bone marrow cells from eight patients with high hyperdiploid (> 50 chromosomes) clones at diagnosis. Alphoid centromeric probes to chromosomes X, 10, 17, and 18, trisomic at diagnosis, were used as appropriate. Three hematologically normal marrows were used as controls. At diagnosis, trisomic interphase cells ranged from 69.3-84.4%. One month later, trisomic and tetrasomic interphase cells were significantly increased over control frequencies in 2/7 cases tested (p < 0.05 and p < 0.001) and trisomy alone in one case (p < 0.05). At two months post-diagnosis, trisomy and tetrasomy were in the control range. Pentasomy and hexasomy, not seen in controls, were found in 5/7 samples at one month and in 1/5 samples at two months. One patient examined in chromosomally normal relapse had 34.4% trisomic cells by FISH at confirmed relapse (p < 0.001). An additional hyperdiploid case, examined at central nervous system relapse, had increased numbers of trisomic cells (p < 0.01) in a morphologically and cytogenetically normal marrow. These findings demonstrate the elimination of aberrant ploidy in most hyperdiploid cases two months from diagnosis and indicate that failure to detect the abnormal clone in relapse may result from selective mitotic activity of chromosomally normal cells, rather than relapse in a cytogenetically normal clone.

Functional dimorphism of two hAgRP promoter SNPs in linkage disequilibrium.

The agouti related protein (AgRP) exerts its anabolic effects on food intake by antagonising the alpha-melanocyte stimulating hormone (alpha-MSH) at its receptors, melanocortin receptors 3 and 4 (MC3R and MC4R). A single nucleotide polymorphism (SNP) in the promoter of the human AgRP (hAgRP), -38C>T, was associated with low body fatness. The -38T allele that was associated with low body fatness also resulted in lower promoter activity. Here we report a novel SNP, -3019G>A, again in the promoter of hAgRP, which is in complete linkage disequilibrium (LD) with the -38C>T SNP (linked alleles: -3019A/-38T and -3019G/-38C). Functional analyses in a human adrenal and two mouse hypothalamus cell lines showed that the -3019A allele had significantly higher promoter activity. Hence, the two linked alleles (-3019A and -38T) had opposite effects on promoter function and yet they were both associated with low body fatness. The region encompassing the -38C>T SNP had approximately 1000-fold higher activity than the region encompassing the -3019G>A SNP, potentially determining the net functional effect between these two SNPs.

Induction of uncoupling protein expression in brown and white adipose tissue by leptin.

Deposition of excess body fat occurs when energy intake chronically exceeds energy expenditure. In ob/ob mice, the absence of leptin affects both components of the energy balance equation, and the mice become morbidly obese after weaning. Treatment of ob/ob mice with exogenous leptin reduces body weight by decreasing food intake and stimulating energy utilization, but even when saline- and leptin-injected ob/ob mice are pair-fed, mice receiving leptin lose significantly more weight. Therefore, the purpose of the present study was to test the hypotheses that uncoupling protein-1 (UCP1) expression is reduced in adipose tissue from ob/ob mice and is restored by treatment with exogenous leptin. Lean and ob/ob mice (5-6 weeks old) were housed at 23 C and treated with leptin (20 microg/g BW x day) for 3 days before they were killed. Compared with levels in lean littermates, UCP1 messenger RNA (mRNA) and protein levels were lower in brown adipose tissue (BAT) and retroperitoneal white adipose tissue (WAT) from ob/ob mice. Treatment of ob/ob mice with leptin reduced body weight and produced a 4- to 5-fold increase in UCP1 mRNA levels in both interscapular BAT and retroperitoneal WAT. The increases in UCP1 mRNA were accompanied by comparable increases in UCP1 protein in mitochondrial preparations from each tissue. Given that the sole known function of UCP1 is to uncouple oxidative phosphorylation, the present results are consistent with the conclusion that leptin stimulates energy utilization in ob/ob mice by increasing thermogenic activity and capacity (UCP1). In addition, the present results suggest that decreased UCP1 expression in BAT and WAT of ob/ob mice is in part responsible for their increased metabolic efficiency and propensity to become obese.

The gene structure and minimal promoter of the human agouti related protein.

The murine agouti related protein (mAGRP) is upregulated in obese and diabetic mice and stimulates hyperphagia when administered intracerebroventricularly (i.c.v.) or when overexpressed in transgenic mice. The human ortholog, hAGRP, has been isolated and has similar molecular and physiological properties. Here, we report the complete gene structure of the human AGRP gene and upstream regions with differential promoter activity. A polymorphism, A67T, in the third exon was identified but was not associated with obesity- or type 2 diabetes-related phenotypes. Putative binding sites for transcription factors were identified in the promoter of the gene including recognition sites for the signal transducers and activators of transcription (STATs) that may potentially mediate leptin's action in the hypothalamus. The upstream non-coding exon had significant promoter activity in a periphery- but not so in a hypothalamus-derived cell line, suggesting that it might contain the minimal promoter required for expression of the short transcript of hAGRP in the periphery.

Endogenous mutations in human uncoupling protein 3 alter its functional properties.

Human uncoupling protein (UCP3) is a mitochondrial transmembrane carrier that uncouples oxidative phosphorylation and is a candidate gene for obesity. Expression of native human UCP3 mutations in yeast showed complete loss (R70W), significant reduction (R143X), or no effect (V102I and IVS6+1G > A) on the uncoupling activity of UCP3. It is concluded that certain mutations in UCP3 alter its functional impact on membrane potential (deltaphi), possibly conferring susceptibility to develop metabolic diseases.

Gallstone perforation and obstruction of the duodenal bulb.

A 69-year-old woman had a large gallstone eroded through the wall of the gallbladder and into the duodenum. The gallstone became fixed within the cholecystoduodenal fistula and produced a duodenal obstruction. At the time of the diagnosis of this problem, the patient had had a three-week period of epigastric pain and prolonged vomiting. She was treated by removal of the stone and cholecystectomy. The duodenal fistula was closed in two layers, and a gastrojejunostomy and a truncal vagotomy were carried out to protect the duodenal suture line. A leak from the duodenal closure developed on the fourth day, but this subsided spontaneously after 15 days with the use of sump drainage. Six months later, the patient is doing well and has a normal duodenum and gastrojejunostomy as shown by upper gastrointestinal barium study.

Gestational diabetes mellitus and gene mutations which affect insulin secretion.

We investigated whether genetic mutations known to impair insulin secretion and glucose tolerance are operative in a group of American women with gestational diabetes mellitus. Study groups were comprised of elderly non-diabetic controls (n = 55) with normal glucose tolerance and patients with gestational diabetes (n = 50), together with one family with maturity-onset diabetes of the young (three controls and three affected). No mutations were detected in any exon of the human glucokinase gene or the mitochondrial tRNA[Leu](UUR) gene by single strand conformational analysis and direct exon sequencing. Also, chi2 analysis showed no significant association with gestational diabetes for a polymorphism at position -30 (G --> A) of the beta-cell-specific glucokinase gene promoter. We have determined that glucokinase and mitochondrial tRNA[Leu](UUR) gene mutations, which are known to impair insulin secretion are relatively uncommon and do not constitute a large component of genetic risk for gestational diabetes in the study population.

Concentrations and source apportionment of PM10 and associated elemental and ionic species in a lignite-burning power generation area of southern Greece.

Ambient concentrations of PM10 and associated elemental and ionic species were measured over the cold and the warm months of 2010 at an urban and two rural sites located in the lignite-fired power generation area of Megalopolis in Peloponnese, southern Greece. The PM10 concentrations at the urban site (44.2 ± 33.6 µg m(-3)) were significantly higher than those at the rural sites (23.7 ± 20.4 and 22.7 ± 26.9 µg m(-3)). Source apportionment of PM10 and associated components was accomplished by an advanced computational procedure, the robotic chemical mass balance model (RCMB), using chemical profiles for a variety of local fugitive dust sources (power plant fly ash, flue gas desulfurization wet ash, feeding lignite, infertile material from the opencast mines, paved and unpaved road dusts, soil), which were resuspended and sampled through a PM10 inlet onto filters and then chemically analyzed, as well as of other common sources such as vehicular traffic, residential oil combustion, biomass burning, uncontrolled waste burning, marine aerosol, and secondary aerosol formation. Geological dusts (road/soil dust) were found to be major PM10 contributors in both the cold and warm periods of the year, with average annual contribution of 32.6 % at the urban site vs. 22.0 and 29.0 % at the rural sites. Secondary aerosol also appeared to be a significant source, contributing 22.1 % at the urban site in comparison to 30.6 and 28.7 % at the rural sites. At all sites, the contribution of biomass burning was most significant in winter (28.2 % at the urban site vs. 14.6 and 24.6 % at the rural sites), whereas vehicular exhaust contribution appeared to be important mostly in the summer (21.9 % at the urban site vs. 11.5 and 10.5 % at the rural sites). The highest contribution of fly ash (33.2 %) was found at the rural site located to the north of the power plants during wintertime, when winds are favorable. In the warm period, the highest contribution of fly ash was found at the rural site located to the south of the power plants, although it was less important (7.2 %). Moderate contributions of fly ash were found at the urban site (5.4 and 2.7 % in the cold and the warm period, respectively). Finally, the mine field was identified as a minor PM10 source, occasionally contributing with lignite dust and/or deposited wet ash dust under dry summer conditions, with the summertime contributions ranging between 3.1 and 11.0 % among the three sites. The non-parametric bootstrapped potential source contribution function analysis was further applied to localize the regions of sources apportioned by the RCMB. For the majority of sources, source regions appeared as being located within short distances from the sampling sites (within the Peloponnesse Peninsula). More distant Greek areas of the NNE sector also appeared to be source regions for traffic emissions and secondary calcium sulfate dust.