ADAM10 as a biomarker for Alzheimer's disease: A systematic review.

BACKGROUND: Studies have shown that A Disintegrin and Metalloproteinase 10 (ADAM10) is the main α-secretase in the non-amyloidogenic cleavage of the amyloid precursor protein (APP), avoiding the production of amyloid-ß peptide (Aß), one of the pathological hallmarks of Alzheimer's disease (AD). OBJECTIVE: To investigate ADAM10 from cerebrospinal fluid (CSF) and plasma/serum as a potential biomarker for AD. METHODS: A systematic review was carried out in the MEDLINE/PubMed, Web of Science, Embase, and Scopus databases using the terms and Boolean operators: "Alzheimer" AND "ADAM10" AND "biomarker". Citation searching was also adopted. The inclusion criteria were original studies of ADAM10 in blood or CSF in patients with AD. The risk of bias was assessed using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. The analysis methods were registered in the PROSPERO database (#CRD42021274239). RESULTS: Of the 97 records screened, 17 were included. There is strong evidence for lower levels of ADAM10 in platelets of persons with AD compared to cognitively healthy participants. On the other hand, higher levels of ADAM10 were found in plasma. Regarding CSF, controversial results were found with lower and higher levels of ADAM10 in persons with AD compared to healthy older adults. The differences may be due to diverse reasons, including different sample collection and processing and different antibodies, highlighting the importance of standardizing the experiments and choosing the appropriate antibodies for ADAM10 detection. CONCLUSION: Evidence shows that ADAM10 levels are altered in platelets, plasma, serum, and CSF of individuals with AD. The alteration was evident in all stages of the disease, and therefore, the protein may represent a complementary biomarker for the disease. However, more studies must be performed to establish cut-off values for ADAM10 levels to discriminate AD participants from cognitively unimpaired older adults.

Lack of evidence for longitudinal dissociation of the atrioventricular conduction axis.

Longitudinal dissociation of the aggregated specialized cardiomyocytes within the non-branching portion of atrioventricular conduction axis has proved a controversial topic for both morphologists and electrophysiologists. We have now used morphological methods, including three-dimensional assessment, to revisit, in human, canine, and bovine hearts, the presence or absence of interconnections between the aggregated cardiomyocytes making up the non-branching bundle. We analyzed three datasets from human and canine hearts, and two from bovine hearts, using longitudinal and orthogonal serial histological sections. In addition, we assessed three hearts using translucent India ink injected specimens, permitting assessment of the three-dimensional arrangement of the cardiomyocytes. Using the longitudinal sections, we found numerous oblique interconnections between the groups of specialized cardiomyocytes. When assessing orthogonal sections, we noted marked variation in the grouping of the cardiomyocytes. We interpreted this finding as evidence of bifurcation and convergence of the groups seen in the longitudinal sections. The three-dimensional assessment of the bovine material confirmed the presence of the numerous interconnections. The presence of multiple connections between the cardiomyocytes in the non-branching bundle rules out the potential for longitudinal dissociation.

A thermodynamic view on the microsolvation of ions by rare gas: application to Li+ with argon.

We present a thermodynamic perspective of the microsolvation of ions by rare gas atoms, which is based on parallel tempering Monte Carlo (PTMC) simulations. This allows the establishment of a clear relationship between the structure of the solvation shells and the heat capacity (CV) as a function of the number of individual solvent species. The dependence of CV on the temperature allows the identification of the internal structure rearrangements and the onset of partial or total melting of the clusters. As an application, we have employed the PTMC technique to study the thermodynamic properties of clusters resulting from the microsolvation of Li+ by argon atoms. Specifically, calculations have been carried out for the clusters Li+Arn (n = 4-18, 33, 34, and 38) by applying two different potential energy surfaces (PESs): one includes only two-body interactions, while the other also incorporates three-body contributions. Whenever possible, we compare the present thermodynamic results with global optimization studies carried out previously (F. V. Prudente, J. M. C. Marques and F. B. Pereira, Phys. Chem. Chem. Phys., 2017, 19, 25707; W. S. Jesus et al., Int. J. Quantum Chem., 2019, 119, e25860). We conclude that the melting process arises for lower temperatures when the model PES accounts for three-body interactions. Additionally, we characterize the melting processes of the first and second solvation shells. For some specific clusters, structural rearrangements of the most external argon atoms are observed at very low temperatures.

Chronic alcohol consumption increases inflammation and osteoclastogenesis in apical periodontitis.

AIM: To investigate the effect of chronic alcohol consumption on apical periodontitis in rats. METHODOLOGY: Thirty-two male Wistar rats were arranged into four groups: Control (C): without apical periodontitis and nonalcoholic diet; (AL): without apical periodontitis and alcoholic diet; (AP): with apical periodontitis and nonalcoholic diet; and (AP + AL): with apical periodontitis and alcoholic diet. The alcoholic solution at 20% was given to the AL and AP + AL groups as the sole source of hydration throughout the experiment. AP was induced in the mandibular left first molars at the end of the 4th week. Weight changes and the amount of solid and liquid foods were recorded for 8 weeks. At the end, the animals were euthanized and the jaws removed followed by histological processing for histopathological and RANKL, OPG, TRAP and HIF-1α analyses. The Mann-Whitney test was used for nonparametric data, and anova followed by the Tukey test was performed for parametric data, with P < 0.05. RESULTS: Animals that received the alcoholic diet had a lower weight gain than the other groups (P < 0.05). Control and AL groups did not have an inflammatory response in the periapical tissues. The median score of inflammatory infiltrate was significantly higher in the AP + AL group (2.5) compared to the AP group (1.5; P < 0.05). In the same comparison, AP + AL was associated with score 3 for RANKL and HIF-1α versus score 2 for AP group (P < 0.05). Moreover, the values for TRAP were 3.88 ± 0.70 cells mm-1 for the AP + AL group and 2.43 ± 0.94 cells mm-1 for the AP group (P < 0.05). CONCLUSION: In rats, an alcoholic diet had a significant effect on the severity of apical periodontitis, exacerbating the inflammatory response and osteoclastogenesis.

Microbiological analysis of conjunctival secretion in anophthalmic cavity, contralateral eye and ocular prosthesis of patients with maxillofacial abnormalities.

The purpose of this study was to identify and analyse the micro-organisms present in the conjunctival secretion in anophthalmic cavities of wearers of ocular prostheses, as well as on the prostheses used by them, correlating them with the microbiota of the contralateral eye. Nine patients with maxillofacial abnormalities, wearers of an acrylic resin ocular prosthesis participated in the study. Collections of conjunctival secretions and biofilm were performed on the prosthesis, anophthalmic cavity and contralateral eye for the mycological and bacterial analyses. The data were submitted to statistical analysis, performing a Kendall correlation test to identify the correlation between the collection site and the identified micro-organism (P < 0·05). It was verified that the most prevalent micro-organisms were the Staphylococcus aureus and Staphylococcus epidermidis, independent of the collection site, and that negative cultures for fungi were encountered in 85·2% of collections, independent of the region. It was not possible to establish a correlation among the types of micro-organisms and the collection sites. SIGNIFICANCE AND IMPACT OF THE STUDY: Some evidence suggests that the surface roughness of ocular prostheses can influence interactions with micro-organisms, with greater prejudicial consequences, such as the establishment of biofilms, which could lead to infections. Thus, it becomes extremely important to identify the micro-organisms present on the acrylic surfaces of ocular prostheses, as well as the microbiota of the anophthalmic cavity and contralateral eye of wearers of the same, so that subsequent control measures promote the homeostatic maintenance of the ocular region.

Stability of anterior open bite treatment with bonded spurs associated with high-pull chincup.

OBJECTIVE: To evaluate the stability of anterior open bite (AOB) treatment with bonded spurs associated with high-pull chincup (BS/HPCC). METHODS: The experimental group consisted of 25 Class I AOB patients (15 female, 10 male) treated with BS/HPCC for 1 year. Cephalograms were analysed at pre-treatment (T1), post-treatment (T2) and at the 3-year post-treatment (T3) stage with the patients mean ages of 8.10, 9.14 and 12.18 years, respectively. The control group consisted of 23 subjects (13 female, 10 male) with normal occlusion, with comparable ages at the 3 stages (8.45, 9.45 and 12.50 years at T1, T2 and T3, respectively). T tests were used for intergroup comparisons at T1 and to compare the changes during the 3-year post-treatment period (T2-T3). Intragroup comparison in the treated group was evaluated with dependent t tests between T1 and T2. Correlations between the overbite changes in the T2-T3 period, the pre-treatment AOB severity and the amount of correction achieved during treatment were evaluated with Pearson's correlation coefficient. RESULTS: No statistically significant relapse of the AOB was found at T3. Only 1 patient had a clinically significant AOB relapse. Neither the pre-treatment AOB severity nor the amount of correction was related to overbite changes during the 3-year post-treatment period. CONCLUSIONS: There was no statistically significant relapse of the AOB, and the clinical stability of AOB correction 3-year post-treatment was of 96%.

Assessment of Interexaminer Agreement in the Detection of Condyle Morphology and positioning with Two Methods: Radiographic and Tomographic.

AIM: This study aims at evaluating the interexaminer agreement between radiographic and tomographic methods to determine condyle morphological variations and positioning. MATERIALS AND METHODS: The sample comprised 100 individuals aged 13 to 30 years, from the patient files of University of North Paraná. The assessment of condyles morphology and positioning was performed in images of digital panoramic radiography (DPR) and reconstructed panoramic images from the cone beam computed tomography (CBCT) scans, by using the Dolphin three-dimensional (3D) program. The condyle morphology was categorized as flat, convex, and angular as well as its positioning classified into anterior, posterior, and concentric. Three calibrated examiners performed this subjective evaluation. After that, another examiner performed an objective assessment of the condyles positioning using tomographic sagittal scans of the condyles, applying the same 3D program. This objective evaluation of the condyle position, considered the gold standard (GS), was achieved by using a formula based on the measurement values of the joint spaces, anterior and posterior. The kappa test was used to assess the interexaminer agreement in determining the condyles morphology and positioning, as well as between the condyle positioning results determined by the examiners and the GS. RESULTS: The results showed poor agreement among examiners and between the subjective and objective condyle positioning evaluation. CONCLUSION: It was concluded that the panoramic radiography (PR), either digitalized or reconstructed from CBCT scans, is not suitable for determining variations in condyle morphology and position. CLINICAL SIGNIFICANCE: Whenever it is necessary to evaluate the mandibular condyle during the orthodontic screening, the orthodontist should consider another image modality better than the PR.

Impaired sperm motility in HIV-infected men: an unexpected adverse effect of efavirenz?

STUDY QUESTION: Are antiretroviral therapies associated with semen alterations in HIV-infected men? SUMMARY ANSWER: Antiretroviral regimens that included the non-nucleosidic reverse transcriptase inhibitor efavirenz were associated with a significant impairment of sperm motility, whereas regimens without efavirenz were not associated with significant semen changes. WHAT IS KNOWN ALREADY: Semen alterations including decreased ejaculate volume and sperm motility have been reported in HIV-infected men. The hypothesis ascribing reduced sperm motility to damages induced in sperm mitochondria by nucleosidic (or nucleotidic) reverse transcriptase inhibitors (NRTIs) has not been confirmed in HIV-infected patients and the effects of antiretroviral treatments on semen parameters remain unclear. STUDY DESIGN, SIZE, DURATION: This case-control study compared semen characteristics across 378 HIV-1 infected patients receiving different antiretroviral regimens or never treated by antiretroviral drugs, in whom an initial semen analysis was done between 2001 and 2007. PARTICIPANTS/MATERIALS, SETTING, METHODS: The patients were partners from serodiscordant couples requesting medical assistance to procreate safely. Their status with regard to antiretroviral therapy at the time of semen analysis was categorized as follows: 1/ never treated patients (n = 66); 2/ patients receiving NRTIs only (n = 49); 3/ patients receiving a NRTIs + protease inhibitor (PI) regimen (n = 144); 4/ patients receiving a NRTIs + non-nucleosidic reverse transcriptase inhibitor (NNRTI) regimen (n = 119). Semen parameters were assessed through standard semen analysis. Additional analyses included measurement of sperm motion parameters using computer-assisted semen analysis, seminal bacteriological analysis, seminal biochemical markers and testosterone plasmatic levels. All analyses were performed in the Cochin academic hospital. The data were analyzed through multivariate analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Sperm motility was the only semen parameter which significantly varied according to treatment status. The median percentage of rapid spermatozoa was 5% in the group of patients receiving a regimen including efavirenz versus 20% in the other groups (P < 0.0001). Accordingly, sperm velocity was reduced by about 30% in this group (P < 0.0001). The role of chance was minimized by the strict definition and the size of the study population, which included a large enough group of never treated patients, the controlled conditions of semen collection and analysis, the multivariate analysis, the specificity and the high significance level of the observed differences. LIMITATIONS, REASONS FOR CAUTION: The design of the study did not allow demonstrating a causal link between exposure to efavirenz and sperm motility. WIDER IMPLICATIONS OF THE FINDINGS: As efavirenz is widely used in current antiretroviral therapy, these findings may concern many HIV-infected men wishing to have children. This justifies further assessment of the consequences on fertility of the exposure to efavirenz. Moreover, the possibility of common cellular impacts underlying adverse effects of efavirenz in sperm cells and neurons deserved investigation. STUDY FUNDING/COMPETING INTERESTS: No external funding was used for this study. None of the authors has any conflict of interest to declare.

Chromosomal organization of repetitive DNA in Sorubim lima (Teleostei; Pimelodidae).

Interspaced repetitive DNA elements and segmental duplications have been extensively analyzed in fishes through physical chromosome mapping methods, providing a better comprehension of the structure and organization of the genome of this group. In order to contribute to this scenario, a sequence integration study of different classes of repetitive DNA with high resolution physical chromosome mapping was performed in Sorubim lima. Fluorescence in situ hybridization (FISH) and fiber-FISH with probes for 18S and 5S rRNA genes, TTAGGGn sequence and non-LTR retrotransposon family members Rex1, Rex3 and Rex6 showed that non-LTR elements may be dispersed in the chromosome set with relative concentration in heterochromatic regions, as shown by Rex1, or may even intercalate in 45S rDNA and the telomeric sequence, as found for Rex3 and Rex6. These results reinforce the presence of preferential regions of retroelement accumulation and contribute to a better understanding of the genomic organization of some repetitive DNA classes in fishes.

Maintaining normothermia immediately after birth in preterm infants <34 weeks' gestation: A systematic review and meta-analysis.

AIM: To evaluate delivery room (DR) interventions to prevent hypothermia and improve outcomes in preterm newborn infants <34 weeks' gestation. METHODS: Medline, Embase, CINAHL and CENTRAL were searched till 22nd July 2022. Randomized controlled trials (RCTs), non-RCTs and quality improvement studies were considered. A random effects meta-analysis was performed, and the certainty of evidence was evaluated using GRADE guidelines. RESULTS: DR temperature of ≥23 °C compared to standard care improved temperature outcomes without an increased risk of hyperthermia (low certainty), whereas radiant warmer in servo mode compared to manual mode decreased mean body temperature (MBT) (moderate certainty). Use of a plastic bag or wrap (PBW) improved normothermia (low certainty), but with an increased risk of hyperthermia (moderate certainty). Plastic cap improved normothermia (moderate certainty) and when combined with PBW improved MBT (low certainty). Use of a cloth cap decreased moderate hypothermia (low certainty). Though thermal mattress (TM) improved MBT, it increased risk of hyperthermia (low certainty). Heated-humidified gases (HHG) for resuscitation decreased the risk of moderate hypothermia and severe intraventricular hemorrhage (very low to low certainty). None of the interventions was shown to improve survival, but sample sizes were insufficient. CONCLUSIONS: DR temperature of ≥23 °C, radiant warmer in manual mode, use of a PBW and a head covering is suggested for preterm newborn infants <34 weeks' gestation. HHG and TM could be considered in addition to PBW provided resources allow, in settings where hypothermia incidence is high. Careful monitoring to avoid hyperthermia is needed.

Growth trends in boys and girls (10-17 years-old) from autonomous region of Madeira, Portugal between 1996-1998 and 2007-2009.

BACKGROUND: Growth trends have never been studied in adolescents of the Autonomous Region of Madeira, Portugal. AIMS: To analyse growth trends in weight, height, body mass index (BMI), waist circumference (WC), mid-upper arm circumference (MUAC) and triceps skin-fold thickness (TST) of adolescents (10-17 years old) of the Autonomous Region of Madeira between 1996-1998 and 2007-2009. SUBJECTS AND METHODS: A cross-sectional study was carried out between 2007-2009, including 4314 adolescents, 2237 girls and 2077 boys (10-17 years old). To study secular growth trends, data were compared with a sample from 1996-1998, comparing the means for each anthropometric variable by age and sex using the independent-sample t-test. RESULTS: An average increase was found in weight of 5.8 kg in boys and 6.3 kg in girls; in height of 3.0 cm in boys and 3.7 cm in girls; in BMI of 1.5 kg/m(2) in boys and 1.7 kg/m(2) in girls; in WC a difference of 5.6 cm and 4.9 cm for boys and girls, respectively, and for MUAC a difference of 2.7 cm in boys and 2.0 cm in girls. No differences were found in TST in boys, but in girls an increase of 1.2 mm was observed. CONCLUSIONS: A general increase in anthropometric measurements, more marked in weight, BMI, WC and MUAC and at younger ages, was observed.

5α,6α-Ep-oxy-7-norcholestan-3ß-yl acetate.

The title cholestan, C(28)H(46)O(3), was prepared by epoxidation of 7-norcholest-5-en-3ß-yl acetate and crystallized by slow evaporation from an ethano-lic solution. All rings are trans fused. The 3ß-acetate and the 17ß-cholestane side chain are in equatorial positions. The mol-ecule is highly twisted due to its B-nor characteristic. A quantum chemical ab-initio Roothaan Hartree-Fock calculation of the equilibrium geometry of the isolated mol-ecule gives values for bond lengths and valency angles in close agreement with the experimental ones.

6-Methyl-ideneandrost-4-ene-3,17-dione.

In the title compound, C(20)H(26)O(2), which is the 6-methyl-ene derivative of androstenedione and a synthetic percursor of exemestane, the steroid A ring approximates to a sofa (or envelope) conformation, with the methyl-ene group adjacent to the link to the B ring lying out of the plane of the other atoms. The B and C rings have slightly flattened chair conformations and the D ring is an envelope, with the CH group forming the flap. In the crystal, mol-ecules are linked by two distinct C-H⋯O hydrogen bonds, involving acidic H atoms close to C=C and C=O double bonds.

N-Hexyl-3-(4-hy-droxy-3,5-dimeth-oxy-phen-yl)propanamide.

In the title compound, C(17)H(27)NO(4), which is an hydro-sinapic acid derivative with increased lipophilicity conferred by an additional alkyl chain, the central and the hexyl linear chains contain slightly shorter bond lengths [C-N = 1.316 (2) Å; average linear chain C-C = 1.487 (6) Å] than reported average values [Csp(2)-N = 1.334, C-C for CH(2)-CH(2) = 1.524 and 1.513 Šfor CH(2)-CH(3)]. The 4-hy-droxy-3,5-dimeth-oxy-phenyl plane [r.m.s. deviation 0.055 (12) Å] makes an angle of 59.89 (5)° with the central plane of the mol-ecule (composed of the N atom, the carbonyl group and the two methyl-ene C atoms linking the carbonyl group and the ring, [r.m.s. deviation 0.0026 (10) Å], which, in turn, makes an angle of 64.24 (13)° with the essentially planar hexyl chain [r.m.s. deviation 0.035 (18) Å]. The N-H group of the amide group is involved in a bifurcated hydrogen bond towards the hy-droxy and one of the meth-oxy O atoms of the 4-hy-droxy-3,5-dimeth-oxy-phenyl substituent of a neighbouring mol-ecule, forming a two-dimensional network in the (100) plane. In addition, the same hy-droxy group acts as a donor towards the carbonyl O atom of another neighbouring mol-ecule, forming chains running along the b axis.

Genetic relationships between efficiency traits and gut microbiota traits in growing pigs being fed with a conventional or a high-fiber diet.

In pigs, the gut microbiota composition plays a major role in the process of digestion, but is influenced by many external factors, especially diet. To be used in breeding applications, genotype by diet interactions on microbiota composition have to be quantified, as well as their impact on genetic covariances with feed efficiency (FE) and digestive efficiency (DE) traits. This study aimed at determining the impact of an alternative diet on variance components of microbiota traits (genera and alpha diversity indices) and estimating genetic correlations between microbiota and efficiency traits for pigs fed a conventional (CO) or a high-fiber (HF) diet. Fecal microbes of 812 full-siblings fed a CO diet and 752 pigs fed the HF diet were characterized at 16 weeks of age by sequencing the V3-V4 region of the 16S rRNA gene. A total of 231 genera were identified. Digestibility coefficients of nitrogen, organic matter, and energy were predicted analyzing the same fecal samples with near infrared spectrometry. Daily feed intake, feed conversion ratio, residual feed intake and average daily gain (ADG) were also recorded. The 71 genera present in more than 20% of individuals were retained for genetic analyses. Heritability (h²) of microbiota traits were similar between diets (from null to 0.38 ±â€…0.12 in the CO diet and to 0.39 ±â€…0.12 in the HF diet). Only three out of the 24 genera and two alpha diversity indices with significant h² in both diets had genetic correlations across diets significantly different from 0.99 (P < 0.05), indicating limited genetic by diet interactions for these traits. When both diets were analyzed jointly, 59 genera had h² significantly different from zero. Based on the genetic correlations between these genera and ADG, FE, and DE traits, three groups of genera could be identified. A group of 29 genera had abundances favorably correlated with DE and FE traits, 14 genera were unfavorably correlated with DE traits, and the last group of 16 genera had abundances with correlations close to zero with production traits. However, genera abundances favorably correlated with DE and FE traits were unfavorably correlated with ADG, and vice versa. Alpha diversity indices had correlation patterns similar to the first group. In the end, genetic by diet interactions on gut microbiota composition of growing pigs were limited in this study. Based on this study, microbiota-based traits could be used as proxies to improve FE and DE in growing pigs.

The link between the composition of the gut microbiota, i.e the composition of microorganisms in the gut, in pigs and their feed efficiency, i.e. their ability to utilize nutrients, as well as their ability to digest were studied from a genetic point of view. A family structure of 1,564 pigs were studied and fed with two different diets. One of the full-sib was fed a conventional diet used in breeding farms and the other one an alternative diet containing raw materials, less expensive but with a higher content of dietary fibers more difficult to digest. This study has shown that some microbiota microorganisms were genetically correlated with feed and digestive efficiency performances, positively or negatively, depending on the microorganisms. In addition, the diversity of microorganisms in the animal's gut was favorably correlated with the feed and digestive performances studied. Therefore, there is a genetic link between these performances and the composition of the animal's gut microbiota. Thus, a potential genetic selection on some intestinal microorganisms or diversity of microorganisms would allow to improve these performances, and in particular when pigs are fed with diet more difficult to digest.

Maintaining normal temperature immediately after birth in late preterm and term infants: A systematic review and meta-analysis.

AIM: Prevention of hypothermia after birth is a global problem in late preterm and term neonates. The aim of this systematic review and meta-analysis was to evaluate delivery room strategies to maintain normothermia and improve survival in late preterm and term neonates (≥34 weeks' gestation). METHODS: Medline, Embase, CINAHL, CENTRAL and international clinical trial registries were searched. Randomized controlled trials (RCTs), quasi-RCTs and observational studies were eligible for inclusion. Risk of bias for each study and GRADE certainty of evidence for each outcome were assessed. RESULTS: 25 RCTs and 10 non-RCTs were included. Room temperature of 23 °C compared to 20 °C improved normothermia [Risk Ratio (RR), 95% Confidence Interval (CI): 1.26, 1.11-1.42)] and body temperature [Mean Difference (MD), 95% CI: 0.30 °C, 0.23-0.37 °C), and decreased moderate hypothermia (RR, 95% CI: 0.26, 0.16-0.42). Skin to skin care (SSC) compared to no SSC increased body temperature (MD, 95% CI: 0.32, 0.10-0.52), reduced hypoglycemia (RR, 95% CI: 0.16, 0.05-0.53) and hospital admission (RR, 95% CI: 0.34, 0.14-0.83). Though plastic bag or wrap (PBW) alone or when combined with SSC compared to SSC alone improved temperatures, the risk-benefit balance is uncertain. Clinical benefit or harm could not be excluded for the primary outcome of survival for any of the interventions. Certainty of evidence was low to very low for all outcomes. CONCLUSIONS: Room temperature of 23 °C and SSC soon after birth may prevent hypothermia in late preterm and term neonates. Though PBW may be an effective adjunct intervention, the risk-benefit balance needs further investigation.

Physical mapping of 5S rDNA in two species of Knifefishes: Gymnotus pantanal and Gymnotus paraguensis (Gymnotiformes).

Physical mapping of 5S rDNA in 2 species of knifefishes, Gymnotuspantanal and G. paraguensis (Gymnotiformes), was performed using fluorescence in situ hybridization with a 5S rDNA probe. The 5S rDNA PCR product from the genomes of both species was also sequenced and aligned to determine non-transcribed spacer sequences (NTS). Both species under study had different patterns of 5S rDNA gene cluster distribution. While in the karyotype of G. pantanal two 5S rDNA-bearing pairs were observed, the karyotype of G. paraguensis possessed as many as 19 such pairs. Such multiplication of 5S rDNA gene clusters might be caused by the involvement of transposable elements because the NTS of G. paraguensis was 400 bp long with high identity (90%) with a mobile transposable element called Tc1-like transposon, described from the cyprinid fish Labeo rohita.

Repetitive DNA and meiotic behavior of sex chromosomes in Gymnotus pantanal (Gymnotiformes, Gymnotidae).

Neotropical fishes have a low rate of chromosome differentiation between sexes. The present study characterizes the first meiotic analysis of sex chromosomes in the order Gymnotiformes. Gymnotus pantanal - females had 40 chromosomes (14m/sm, 26st/a) and males had 39 chromosomes (15m/sm, 24st/a), with a fundamental number of 54 - showed a multiple sexual determination chromosome system of the type X(1)X(1)X(2)X(2)/X(1)X(2)Y. The heterochromatin is restricted to centromeres of all chromosomes of the karyotype. The meiotic behavior of sex chromosomes involved in this system in males is from a trivalent totally pared in the pachytene stage, with a high degree of similarity. The cells of metaphase II exhibit 19 and 20 chromosomes, normal disjunction of sex chromosomes and the formation of balanced gametes with 18 + Y and 18 + X(1)X(2) chromosomes, respectively. The small amount of heterochromatin and repetitive DNA involved in this system and the high degree of chromosome similarity indicated a recent origin of the X(1)X(1)X(2)X(2)/X(1)X(2)Y system in G. pantanal and suggests the existence of a simple ancestral system with morphologically undifferentiated chromosomes.

Markers of metabolic syndrome in obese children before and after 1-year lifestyle intervention program.

PURPOSE: Excess weight may be related to the development of adverse cardiometabolic risk factors in children. The aim of this study was to evaluate the effect of a lifestyle intervention program (nutrition and exercise counseling) on anthropometric parameters and metabolic syndrome (MS) components in Portuguese overweight/obese children. METHODS: A total of 83 overweight/obese children aged 7-9 years were assigned to a 1-year individual or group-based treatment (GT); 61 children (z-score BMI (zBMI): 1.93 ± 0.28; 27 boys and 34 girls) completed the program. Anthropometric and biochemical parameters were assessed at baseline, at 6 months and at 1 year. RESULTS: The overweight/obese children, compared to normal-weight ones, presented significantly higher blood pressure, total-cholesterol, total-cholesterol/high density lipoprotein cholesterol (HDL) ratio, triglycerides, Apolipoprotein B and C-reactive protein levels, while HDL and Apolipoprotein A-I were significantly lower. At baseline, the prevalence of MS was 16.4% in overweight/obese and 0% in normal-weight children. The number of components of MS was significantly higher in children with higher zBMI. Lifestyle intervention led to a significant improvement in zBMI, waist circumference/height ratio, HDL, triglycerides, Apolipoprotein A-I, and Apolipoprotein B levels. The prevalence of MS decreased to 14.8%. The GT intervention seems to be more successful, with a significant decrease in zBMI and an increase in HDL and a lower drop-out rate. CONCLUSIONS: Overweight/obese children have multiple risk factors associated with the MS. Lifestyle intervention, both individual and group-based treatment, led to an improvement in the degree of overweight/obesity and in MS components.

Two genetic stocks of Steindachneridion melanodermatum living in sympatry in nature and genetic variability of wild parents and F1 generation.

Steindachneridion melanodermatum is a large Brazilian catfish, highly prized for sport fishing and for its meat. Specimens of this species, both caught in nature from Iguacu River and F(1) fish born in captivity, were analyzed with regard to patterns of RAPD molecular markers. Genetic similarity ranged from 0.57 to 0.95; two groups were determined for the wild specimens. The results suggest different genetic lineages in sympatry in nature. Heterozygosity and percentage of polymorphic loci were 0.31 and 79% and 0.23 and 62%, respectively, for the two populations of wild specimens and 0.26 and 66%, respectively, for those born in captivity.