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BACKGROUND: Evidence-based interventions to protect against cognitive decline among older adults at risk for Alzheimer's disease and related dementias (ADRD) are urgently needed. Rehabilitation approaches to support memory and behavioral/lifestyle interventions are recognized as promising strategies for preserving or improving cognitive health, although few previous interventions have combined both approaches. This paper describes the protocol of the Brain Boosters intervention, which synergistically combines training in compensatory and healthy lifestyle behaviors and supports implementation and tracking of new behaviors with a digital application. METHODS: The study utilizes a single-site, single-blinded, randomized controlled design to compare a structured lifestyle and compensatory aid intervention to an education-only self-guided intervention. We plan to enroll 225 community-dwelling adults (25% from underrepresented groups) aged 65 + who endorse subjective cognitive decline (SCD) and low baseline levels of healthy lifestyle behaviors. Both interventions will be administered in group format, consisting of 15 two-hour classes that occur weekly for ten weeks and taper to bi-monthly and monthly, for an intervention duration of 6 months. Participants in both interventions will receive education about a variety of memory support strategies and healthy lifestyle behaviors, focusing on physical and cognitive activity and stress management. The structured intervention will also receive support in adopting new behaviors and tracking set goals aided by the Electronic Memory and Management Aid (EMMA) digital application. Primary outcomes include global cognition (composite of memory, attention, and executive function tests) and everyday function (Everyday Cognition Questionnaire). Data will be collected at baseline and outcome visits, at approximately 6, 12, and 18 months. Qualitative interviews, self-report surveys (e.g., indicators of self-determination, health literacy) and EMMA data metrics will also be used to identify what components of the intervention are most effective and for whom they work. DISCUSSION: Successful project completion will provide valuable information about how individuals with SCD respond to a compensation and preventative lifestyle intervention assisted by a digital application, including an understanding of factors that may impact outcomes, treatment uptake, and adherence. The work will also inform development, scaling, and personalization of future interventions that can delay disability in individuals at risk for ADRD. TRIAL REGISTRATION: ClinicalTrials.gov. (NCT05027789, posted 8/30/2021).

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OBJECTIVES: We aimed to review the literature regarding the use of machine learning to predict chronic diseases. STUDY DESIGN: This was a systematic review. METHODS: The searches included five databases. We included studies that evaluated the prediction of chronic diseases using machine learning models and reported the area under the receiver operating characteristic curve values. The Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis scale was used to assess the quality of studies. RESULTS: In total, 42 studies were selected. The best reported area under the receiver operating characteristic curve value was 1, whereas the worst was 0.74. K-nearest neighbors, Naive Bayes, deep neural networks, and random forest were the machine learning models most frequently used for achieving the best performance. CONCLUSION: We found that machine learning can predict the occurrence of individual chronic diseases, progression, and their determinants and in many contexts. The findings are original and relevant to improve clinical decisions and the organization of health care facilities.

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BACKGROUND: Cryolipolysis with plates is a method of applying cooling without a vacuum system, which can be used in regions with less chance of forming a "crease." OBJECTIVE: To investigate the effects of cryolipolysis using a plate-shaped applicator (Crioplac) in the treatment of fat. MATERIALS AND METHODS: This is an experimental study in which women aged 25 to 45 years with adiposity located in the abdomen participated. Two applications of 75 min were made, using 04 plates in the abdomen regions, with -4 degree C being programmed as a temperature parameter. Anthropometric and ultrasound assessments were performed, and a satisfaction questionnaire on the validated treatment was conducted. The reassessments were performed 30 and 60 days after the first intervention. RESULTS: A reduction in adiposity was observed in the measurements of perimetry, plicometry and abdominal ultrasound (p<0.05). It was found that about 62.5% of the volunteers reported an improvement in water retention, about 62.5% reported the presence of loose clothing, and 31.3% reported satisfaction with the results obtained. It was observed that 18.5% of the volunteers reported that the treatment was excellent. CONCLUSION: The Crioplace method proved to be effective in reducing adiposity, with a high clinical satisfaction with the reduction in body measurements.

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BACKGROUND: Plate cryolipolysis is a method of applying cooling without a vacuum system, which can be used in regions with less possibility of skin suction or fibrosis. OBJECTIVE: To investigate the effects of cryolipolysis with the use of plate-shaped applicators (CrioPlaceTM) for localized fat treatment. METHODS: The sample consisted of men aged 20 to 45 years with complaints of localized adiposity in the abdominal region and flanks. Two plates were positioned in the flank and abdomen regions, respectively. They received two 60-min applications in the temperature of -2°C. The anthropometric, thermographic and ultrasound assessments were performed, and a satisfaction questionnaire was applied after treatment. The re-evaluations occurred 30 and 60 days after the first intervention. RESULT: A reduction in adiposity was observed in flank region plicometry (p<0.05) and abdominal and flank ultrasound (p < 0.05). About 66.7% of the volunteers reported less water retention, about 41.7% reported that their clothes were looser, and 100% reported overall satisfaction. Fifty percent rated the treatment as excellent and 58.3% felt improvement in overall aesthetics. CONCLUSION: The CrioPlaceTM method was effective in reducing localized adiposity, with clinical satisfaction of measurement reduction, both in plicometry and ultrasound analyses, with highlights to the flank region results.

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The natural history of mimiviruses (i.e., viruses that are members of the Mimivirus genus) is a challenge for modern biology. A new domain of life to include these organisms has been proposed from analysis of gene conservation. We analyzed the evolutionary relationship of proteins involved in the translation system, and our data show that mimiviruses are a sister group of Eukarya. New data about the origins of Eukarya, in which Eukarya appears as a branch derived from the Archaea domain, were discussed, and we suggest that the mimiviruses emerged from the initial population that gave origin to Eukarya and that, in this way are not part of a new domain of life.

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The aim of this study was to evaluate the effect of a low-level laser therapy in combination with toluidine blue on polysaccharides and biofilm of Streptococcus mutans. S. mutans biofilms were formed on acrylic resin blocks. These biofilms were exposed eight times/day to 10 % sucrose, and two times/day, they were subjected to one of the following treatments: G1, 0.9 % NaCl as a negative control; G2, 0.12 % chlorhexidine digluconate (CHX) as a positive antibacterial control; and G3 and G4 antimicrobial photodynamic therapy (aPDT) combined with toluidine blue using dosages of 320 and 640 J/cm(2), respectively. The experiment was performed in triplicate. The biofilm formed on each block was collected for determination of the viable bacteria and concentration of insoluble extracellular polysaccharides (IEPS) and intracellular polysaccharides (IPS). CHX and aPDT treatments were able to inhibit bacterial growth in comparison with negative control (p < 0.05). The aPDT treatment reduced the number of viable bacteria formed in the S. mutans biofilm, in a dose-dependent manner (p < 0.05). The concentration of IEPS and IPS in the biofilms formed in presence of aPDT did not differ each other or in comparison to CHX (p > 0.05). The results suggest that low-level laser therapy presents effects on biofilm bacteria viability and in polysaccharides concentration.

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The microbial community of the reproductive appara-tus, when known, can provide information about the health of the host. Metagenomics has been used to characterize and obtain genetic infor-mation about microbial communities in various environments and can relate certain diseases with changes in this community composition. In this study, samples of vaginal surface mucosal secretions were col-lected from five healthy cows and five cows that showed symptoms of reproductive disorders. Following high-throughput sequencing of the isolated microbial DNA, data were processed using the Mothur soft-ware to remove low-quality sequences and chimeras, and released to the Ribosomal Database Project for classification of operational taxo-nomic units (OTUs). Local BLASTn was performed and results were loaded into the MEGAN program for viewing profiles and taxonomic microbial attributes. The control profile comprised a total of 15 taxa, with Bacteroides, Enterobacteriaceae, and Victivallis comprising the highest representation of OTUs; the reproductive disorder-positive profile comprised 68 taxa, with Bacteroides, Enterobacteriaceae, His-tophilus, Victivallis, Alistipes, and Coriobacteriaceae being the taxa with the most OTU representation. A change was observed in both the community composition as well as in the microbial attributes of the profiles, suggesting that a relationship might exist between the patho-gen and representative taxa, reflecting the production of metabolites to disease progression.

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Este estudo objetivou avaliar e comparar a glicose e o lactato plasmáticos, bem como a insulina e o cortisol séricos, em éguas hígidas, não gestantes, tratadas com: polietilenoglicol 3350 (PEG); ou polietilenoglicol 3350 associado ao Ringer lactato (PEG+RL); ou solução isotônica poliônica enteral (SIPE); ou solução isotônica poliônica enteral associada ao Ringer lactato (SIPE+RL); ou solução de cloreto de sódio a 0,9 por cento (NaCl). A avaliação laboratorial foi realizada nos tempos: imediatamente antes do início dos tratamentos (T0h); com seis horas (T6h) e ao final dos tratamentos (T12h); com 24 (T24h) e 48 horas (T48h) após T0h. Não ocorreu alteração significativa no lactato plasmático. Ocorreu apenas um discreto aumento nos valores da glicose e da insulina no tratamento SIPE, ocasionado pela presença de maltodextrina. O cortisol aumentou nos animais de todos os tratamentos, porém menor nos animais do SIPE. Conclui-se que os tratamentos não alteraram os valores da glicose, do lactato e da insulina em éguas hígidas e que a hidratação enteral em fluxo contínuo realizada no tratamento SIPE ocasionou menos estresse nos animais...

The aim of this study was to evaluate and compare the plasmatic lactate and glucose, serum insulin and cortisol in healthy non pregnant mares treated with: polyethylene glycol 3350 (PEG); or polyethylene glycol 3350 associated with Ringer lactate (PEG+RL), or enteral polionic isotonic solution (EPIS); or enteral polionic isotonic solution associated with Ringer lactate (EPIS+RL); or sodium chloride solution 0.9 percent (NaCl). Laboratory tests were carried out in the following moments: immediately before the start of treatment (T0h), at six hours (T6h) and at the end of treatment (T12h), with 24 (T24h) and 48 hours (T48h) after T0h. The lactate did not change significantly. There was a slight increase in glucose and insulin values in EPIS caused by the presence of maltodextrin. Cortisol increased in animals from all treatments, but this increase was lower in the animals in EPIS. It is concluded that the treatments did not alter the values of glucose, lactate and insulin in healthy mares and the enteral hydration in continuous flow done in the EPIS treatment caused less stress to the animals...

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INTRODUCTION: Aluminum (Al) is a toxic element which may contaminate pharmaceutical products used as individual components to prepare total parenteral nutrition mixtures (TPN). OBJECTIVES: 1) to determine Al levels in the individual components used to prepare TPN mixtures; 2) to compare detected Al levels with those imposed by international regulations (FDA); 3) to calculate the total amount of Al administered to adult and children receiving those typical TPN mixtures. METHODS: Al was determined by Inductively Coupled Plasma- Atomic Emission Spectrometry (ICP-OES) (Perkin Elmer OPTIMA 5100 DV) in 44 individual products, from different labs and lots, belonging to 16 components available in Argentina: dextrose and amino acids for adult formulas and for pediatric formulas: lípids; potassium chloride; sodium chloride, magnesium sulfate; sodium phosphate; calcium gluconate; sodium glycerophosphate, zinc sulfate; multitrace elements; steril water (ampoules and great volume presentations). RESULTS: Al levels were detected in 43 of the 44 the studied components, except sterile water. The components of large volume presented between 249 y 1,580 µg Al/ L, between 4 and 180 times FDA established levels (25 µg Al/ L). Small volume components presented Al levels between 85 y 4,909 g/ L, not declared in labels. CONCLUSIONS: The highest amounts of Al were detected in calcium gluconate, sodium phosphate and multitrace elements. 2) Usually prescribed TPN mixtures would have higher Al levels than those accepted by FDA regulation; 3) The highest aluminum concentration was provided by dextrose, amino acids and lipids in adult TPN mixtures. In neonate TPN mixtures, Al highest amounts were provided by dextrose and calcium gluconate. The calculated concentration of Al in TPN mixtures was higher than those stipulated by international regulation (5 µg Al/kg (body weight)/ d). It would be advisable for manufacturers to declare the content of aluminum in the label, with the aim of avoiding toxicities which would compromise the critical patients' evolution.

Introducción: aluminio (Al) es un elemento tóxico que puede ser contaminante de productos farmacéuticos utilizados para preparar mezclas de nutrición parenteral (NP). Objetivos: 1) determinar la concentración de Al en componentes individuales utilizados para preparar mezclas de NP; 2) comparar las cantidades detectadas con los límites de la regulación internacional (FDA); 3) calcular la cantidad de Al administrada en fórmulas habituales de NP para neonatos, niños y adultos. Materiales y métodos: El Aluminio fue determinado por Espectroscopía de Emisión Atómica-Plasma-Inductivo de Argón (Perkin Elmer 5100 DV) en 44 productos comerciales, de diferentes laboratorios y lotes, correspondientes a 16 componentes individuales: dextrosa; aminoácidos para adultos y pediátricos; lípidos; cloruro de potasio; cloruro de sodio, sulfato de magnesio; fosfato de sodio; gluconato de calcio; glicerofosfato de sodio; sulfato de zinc; elementos multitraza; agua estéril en ampollas y de gran volumen. Resultados: Todos los componentes de gran volumen, excepto el agua, contenían entre 249 y 1.580 µg/L, superando entre 4 y 180 veces mas que los niveles establecidos por la FDA (25 µg/L). Los componentes de pequeño volumen contenían entre 85 y 4.909 µg/L, no declarados en los rótulos. Conclusiones: 1) La mayor cantidad de aluminio se encontró en el gluconato de calcio, fosfato de sodio y elementos multitraza. 2) Las mezclas de uso habitual para NP presentan niveles de Al mayores al límite de FDA. Los componentes que aportan mayor cantidad de aluminio en las mezclas de NP para adultos son: glucosa, aminoácidos y lípidos, pero en las de neonatos, el mayor aporte proviene de la dextrosa y gluconato de calcio. 3) En las mezclas de NP para neonatos, niños y adultos la cantidad de aluminio administrado por kg de peso supera la recomendación de FDA (5 µg/kg de peso /día). Los productos comerciales deberían declarar el contenido de Al para no comprometer la evolución de los pacientes graves.

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Substrate-binding subunits are important components of the solute importation system, known as the osmoprotectant system, which consists of a membrane protein belonging to the ABC superfamily. These molecules recognize specific substrates that have different physiological roles in prokaryotes, i.e., roles that contribute to the survival of these organisms in environments with high concentrations of salt. Using the MEGA software, this study performed a phylogenetic analysis of 431 nucleotide sequences of these subunits, orthologous to each other, collected from the http://www.genome.jp/kegg/ database. This analysis allowed phylogenetic trees to be generated, clearly demonstrating that there was horizontal transfer of some genes through sharing by different organisms. Furthermore, two probable ancestral sequences were generated that showed homology with permeases that transport choline, glycine betaine, and carnitine, which are trimethylamines currently present in various prokaryotes. Therefore, this system probably arose in prokaryotic organisms with the basic function of capturing nutrients, and by performing this basal function and being shared with other organisms, it was fixed in the genome. However, because of prokaryote habitat diversification, this system contributed decisively to the adaptation of these organisms to different environments, especially environments that had a high salt concentration, thus acting as an osmoprotection system, which is how they are currently categorized.

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The aim of the present study was to isolate S. aureus strains resistant to antibiotics, characterize the genotype profiles of resistance staphylococci, and evaluate the efficacy of antiseptic agents and disinfectants used in two public hospitals of Vitoria da Conquista, Bahia, Brazil. Clinical samples were obtained from ICU environments and equipment surfaces in two public hospitals in Vitoria da Conquista. Broth cultures were plated onto mannitol salt agar, and antimicrobial susceptibility testing was performed by the broth microdilution method according to CLSI. MRSA strains were submitted to PCR for detecting the mecA gene. PCR products were purified and sequenced for SCCmec type identification. Moreover, the strains were tested for efficacy of different disinfectant solutions. S. aureus were isolated from 31 and 67 sites in each hospital, respectively. Among the isolates from hospital 1, 07 (22.6%) were resistant to oxacillin while 28 (41.8%) were resistant in hospital 2. Thirty-one were positive for the mecA gene. All isolates showed SCCmec type III genotype characteristics of the Brazilian epidemic clone. In disinfectant tests, sodium hypochlorite (0.5, 1.0 and 2.0%), 2% chlorhexidine gluconate, quaternary ammonium, peracetic acid and formaldehyde were effective against the isolates tested. The strains showed higher resistance to vinegar (4% acetic acid), alcohol and glutaraldehyde. The findings of this study should assist in reducing the occurrence of nosocomial infections and therefore the morbidity, mortality and socio-economic burden caused by prolonged hospitalization.

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BACKGROUND AND PURPOSE: GM volume, WMH volume, and FA are each associated with cognition; however, few studies have detected whether these 3 different types of MR imaging measurements exert independent or additive effects on cognitive performance. To detect their extent of contribution to cognitive performance, we explored the independent and additive contributions of GM atrophy, white matter injury, and white matter integrity to cognition in elderly patients. MATERIALS AND METHODS: Two hundred and 9 elderly patients participated in the study: 97 were CN adults, 65 had MCI, and 47 had dementia. We measured GM on T1-weighted MR imaging, WMH on FLAIR, and FA on DTI, along with psychometrically matched measures of 4 domains of cognitive performance, including semantic memory, episodic memory, executive function, and spatial abilities. RESULTS: As expected, patients with dementia performed significantly more poorly in all 4 cognitive domains, whereas patients with MCI performed generally less poorly than dementia patients, though considerable overlap in performance was present across groups. GM, FA, and WMH each differed significantly between diagnostic groups and were associated with cognitive measures. In multivariate models that included all 3 MR imaging measures (GM, WMH, and FA), GM volume was the strongest determinant of cognitive performance. CONCLUSIONS: These results strongly suggest that MR imaging measures of GM are more closely associated with cognitive function than WM measures across a broad range of cognitive and functional impairment.

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Background: Depressive disorders (TD) is a set of prevalent diseases that require proper diagnosis and treatment. In Chile, the instruments of evaluation and diagnosis are scarce. As a way to address this difficulty, the objective of this study was to validate the Spanish version of the self-reported Patient Health Questionarie (PHQ-9), the consulting population in primary care in Chile. The PHQ-9 to detect depressive symptoms as mild, moderate or severe, and has proven to be an efficient diagnostic tool. Methods: 1327 patients evaluated in June 2005 from five urban general practices of the Commune of Valdivia answered individually the PHQ-9. A subsample was compared with the Hamilton scale for depression, ICD-10 criteria for depression and XX version of the PHQ-9. Results: The PHQ-9 demonstrated a sensitivity of 92 percent and 89 percent specificity in detecting depressive patients, when compared to the Hamilton-D scale. It presents a construct validity and predictive validity concurrent with the ICD-10 criteria for depression. Conclusions: The PHQ-9 showed a psychometric allowing clinical use in primary care patients in Chile.

Introducción: Los trastornos depresivos (TD) son un conjunto de enfermedades prevalentes que requieren de un adecuado diagnóstico y tratamiento. En Chile, los instrumentos de evaluación y diagnóstico son escasos. Como forma de enfrentar esta dificultad, el objetivo del presente estudio fue validar la versión en español del auto-reporte Patient Health Questionarie (PHQ-9), en la población consultante de la atención primaria en Chile. El PHQ-9 permite detectar sintomatología depresiva leve, moderada o severa, y ha demostrado ser un eficiente instrumento de diagnóstico. Material y Método: 1.327 pacientes evaluados en junio 2005, provenientes de 5 consultorios generales urbanos de la Comuna de Valdivia respondieron individualmente el PHQ-9. Una sub-muestra fue comparada con la escala de Hamilton para depresión, los criterios CIE-10 para depresión y la versión XX del PHQ-9. Resultados: El PHQ-9 demuestra una sensibilidad de un 92 por ciento y especificidad de 89 por ciento en la detección de pacientes depresivos, al compararla con la escala de Hamilton-D. Además, presenta una validez de constructo y una validez predictiva concurrente con los criterios de CIE-10 para depresión. Conclusiones: El PHQ-9 mostró un comportamiento psicométrico que permite su utilización clínica en pacientes de atención primaria en Chile.

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Ureaplasma diversum infection in bulls may result in seminal vesiculitis, balanoposthitis and alterations in spermatozoids. In cows, it can cause placentitis, fetal alveolitis, abortion and the birth of weak calves. U. diversum ATCC 49782 (serogroups A), ATCC 49783 (serogroup C) and 34 field isolates were used for this study. These microorganisms were submitted to Polymerase Chain Reaction for 16S gene sequence determination using Taq High Fidelity and the products were purified and bi-directionally sequenced. Using the sequence obtained, a fragment containing four hypervariable regions was selected and nucleotide polymorphisms were identified based on their position within the 16S rRNA gene. Forty-four single nucleotide polymorphisms (SNP) were detected. The genotypic variability of the 16S rRNA gene of U. diversum isolates shows that the taxonomy classification of these organisms is likely much more complex than previously described and that 16S rRNA gene sequencing may be used to suggest an epidemiologic pattern of different origin strains.

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Newborn fat necrosis is an unfrequent disease that compromises the adipose tissue and develops during the first weeks of life. It is characterized by reddish-purple nodules and/or plaques with a hard elastic consistency, isolated or múltiple, localized at the back, shoulders, buttocks, arms, thighs and chin. They evolve spontaneously to regression and unfrequently develop complications, being hypercalcemia the most observed. The pathogenesis of newborn fat necrosis is unknown, although certain risk factors for its development have been identified. Case-report: A 36 weeks preterm male newborn with a clinical picture compatible with fat necrosis. The diagnosis was made according to the clinical findings and his perinatal history, confirming it with pathology. The patient evolution was complete improvement and regression of the lesions, without complications.

La necrosis grasa del recién nacido (NGRN) es una rara enfermedad que afecta al tejido adiposo y que se desarrolla durante las primeras semanas de vida. Se caracteriza por nodulos y/o placas eritemato-violáceas, de consistencia duro-elástica, únicas o múltiples, en dorso, hombros, glúteos, brazos, muslos y mejillas, que evolucionan espontáneamente hacia la regresión. Si bien pueden desarrollarse complicaciones, éstas son infrecuentes, siendo la más importante la hipercalcemia. La patogenia de la NGRN es desconocida, aunque se han identificado factores predisponentes para su desarrollo. Presentamos el caso de un recién nacido de pretérmino de 36 semanas, sexo masculino, que presentó un cuadro clínico compatible con NGRN. El diagnóstico se sospechó en base a la clínica, a los antecedentes perinatales y se confirmó con el estudio histopatológico. El paciente evolucionó satisfactoriamente con regresión de las lesiones y sin presentar complicaciones hasta la fecha.

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An assay using fluorescence resonance energy transfer peptides was developed to assess angiotensin I-converting enzyme (ACE) activity directly on the membrane of transfected Chinese hamster ovary cells (CHO) stably expressing the full-length somatic form of the enzyme. The advantage of the new method is the possibility of using selective substrates for the two active sites of the enzyme, namely Abz-FRK(Dnp)P-OH for somatic ACE, Abz-SDK(Dnp)P-OH for the N domain, and Abz-LFK(Dnp)-OH for the C domain. Hydrolysis of a peptide bond between the donor/acceptor pair (Abz/Dnp) generates detectable fluorescence, allowing quantitative measurement of the enzymatic activity. The kinetic parameter K(m) for the hydrolysis of the three substrates by ACE in this system was also determined and the values are comparable to those obtained using the purified enzyme in solution. The specificity of the activity was demonstrated by the complete inhibition of the hydrolysis by the ACE inhibitor lisinopril. Therefore, the results presented in this work show for the first time that determination of ACE activity directly on the surface of intact CHO cells is feasible and that the method is reliable and sensitive. In conclusion, we describe a methodology that may represent a new tool for the assessment of ACE activity which will open the possibility to study protein interactions in cells in culture.

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BACKGROUND AND PURPOSE: The purpose of this study was to examine the reproducibility of functional MR imaging (fMRI) activation (volume and laterality) within both inferior frontal and temporoparietal regions of interest for both receptive and expressive language tasks. METHODS: Ten healthy volunteers participated in fMRI experiments for 6 language tasks: verb generation, confrontation naming, semantic decision making, visual sentence comprehension, auditory sentence comprehension, and story listening. Each subject was scanned during 2 separate sessions separated by a minimum of 4 weeks. Laterality of activation was defined by laterality indices (LIs), which were calculated by 2 methods: one method based on the measured volume of activation and the other method based on the F statistic of the activation. Reproducibility was calculated by using concurrence ratios for the volume of activation (R(overlap), R(volume)) and test-retest correlation for LIs. RESULTS: All tasks generated reproducible LIs within at least one of the regions of interest, but verb generation produced the highest test-retest correlations (r = 0.99) within both regions of interest. Verb generation was associated with the highest average concurrence ratios within the inferior frontal region of interest (R(overlap) = 45.2; R(volume) = 70.9). In general, the concurrence ratios were lower within the temporoparietal region of interest compared with the inferior frontal region of interest. LIs calculated with F statistics were more reproducible than the LIs calculated by activation volume. CONCLUSION: fMRI is able to provide reproducible LIs in both inferior frontal and temporoparietal regions for assessing hemispheric dominance in language processing. The volume of activation, especially within the temporoparietal regions, is less reproducible than the laterality of activation, so the former should be used with caution.

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The average protein (E+K)/(Q+H) ratio in organisms has already been demonstrated to have a strong correlation with their optimal growth temperature. Employing the Thermo-Search web tool, we used this ratio as a basis to look for thermostable proteins in a mesophile, Xylella fastidiosa. Nine proteins were chosen to have their three-dimensional structures modeled by homology, using mainly proteins from mesophiles as templates. Resulting models featured a high number of hydrophobic interactions, a property that has been previously associated with thermostability. These results demonstrate the interesting possibility of using the (E+K)/(Q+H) ratio to find individual thermostable proteins in mesophilic organisms.

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Most organisms grow at temperatures from 20 to 50 degrees C, but some prokaryotes, including Archaea and Bacteria, are capable of withstanding higher temperatures, from 60 to >100 degrees C. Their biomolecules, especially proteins, must be sufficiently stable to function under these extreme conditions; however, the basis for thermostability remains elusive. We investigated the preferential usage of certain groupings of amino acids and codons in thermally adapted organisms, by comparative proteome analysis, using 28 complete genomes from 18 mesophiles (M), 4 thermophiles (T), and 6 hyperthermophiles (HT). Whenever the percent of glutamate (E) and lysine (K) increased in the HT proteomes, the percent of glutamine (Q) and histidine (H) decreased, so that the E + K/Q + H ratio was >4.5; it was <2.5 in the M proteomes, and 3.2 to 4.6 in T. The E + K/Q + H ratios for chaperonins, potentially thermostable proteins, were higher than their proteome ratios, whereas for DNA ligases, which are not necessarily thermostable, they followed the proteome ratios. Analysis of codon usage revealed that HT had more AGR codons for Arg than they did CGN codons, which were more common in mesophiles. The E + K/Q + H ratio may provide a useful marker for distinguishing HT, T and M prokaryotes, and the high percentage of the amino acid couple E + K, consistently associated with a low percentage of the pair Q + H, could contribute to protein thermostability. The preponderance of AGR codons for Arg is a signature of all HT so far analyzed. The E + K/Q + H ratio and the codon bias for Arg are apparently not related to phylogeny. HT members of the Bacteria show the same values as the HT members of the Archaea; the values for T organisms are related to their lifestyle (intermediate temperature) and not to their domain (Archaea) and the values for M are similar in Eukarya, Bacteria and Archaea

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