Control of proton transport and hydrogenation in double-gated graphene.

The basal plane of graphene can function as a selective barrier that is permeable to protons1,2 but impermeable to all ions3,4 and gases5,6, stimulating its use in applications such as membranes1,2,7,8, catalysis9,10 and isotope separation11,12. Protons can chemically adsorb on graphene and hydrogenate it13,14, inducing a conductor-insulator transition that has been explored intensively in graphene electronic devices13-17. However, both processes face energy barriers1,12,18 and various strategies have been proposed to accelerate proton transport, for example by introducing vacancies4,7,8, incorporating catalytic metals1,19 or chemically functionalizing the lattice18,20. But these techniques can compromise other properties, such as ion selectivity21,22 or mechanical stability23. Here we show that independent control of the electric field, E, at around 1 V nm-1, and charge-carrier density, n, at around 1 × 1014 cm-2, in double-gated graphene allows the decoupling of proton transport from lattice hydrogenation and can thereby accelerate proton transport such that it approaches the limiting electrolyte current for our devices. Proton transport and hydrogenation can be driven selectively with precision and robustness, enabling proton-based logic and memory graphene devices that have on-off ratios spanning orders of magnitude. Our results show that field effects can accelerate and decouple electrochemical processes in double-gated 2D crystals and demonstrate the possibility of mapping such processes as a function of E and n, which is a new technique for the study of 2D electrode-electrolyte interfaces.

8-Pmmn borophene: edge states in competition with Landau levels and local vacancy states.

The tight-binding method is used to investigate the electronic and magnetic properties of borophene nano-ribbons (BNRs) in the presence of a perpendicular magnetic field. Most BNRs exhibit metallic characteristics due to edge bands. Additionally, the appearance of Landau levels (LLs) is strongly influenced by the edge states, contrasting with the sheet platform which produces distinct LLs. We also investigated single atomic vacancy disorders in BNRs and observed localized vacancy states (LVSs) resulting from atomic disorder. Both LVSs and LLs are influenced by the edge states, underscoring that the electronic and magnetic properties of BNRs are strongly edge-dependent. This aspect is crucial for consideration in experimental, theoretical, and computational studies.

Energy and protein levels in dairy cow diets to recover milk ethanol stability.

The objective of this study was to evaluate the effect of energy and protein in the diet on the recovery of milk ethanol stability (MES) induced by feed restriction. Twelve Holstein and Holstein x Jersey crossbred cows with an average of 146 ± 50 d in milk, 575.4 ± 70 kg of body weight, and 18.93 ± 5.46 kg/d of milk yield were distributed in a 3x3 Latin square design with 3 treatments and 3 experimental periods. Each experimental period lasted 24 d, comprising 3 phases: a 13-d adaptation phase (100E+100P), a 4-d induction phase for milk ethanol instability (50E+50P), and a 7-d recovery phase for MES (3 treatments). The 3 treatments during the recovery phase consisted of 3 diets aiming to meet the requirements of energy and protein (100E+100P), only energy (100E+50P), or only protein (50E+100P). The diet during the adaptation and induction phases was common for all cows. The energy and protein levels to meet each cow's requirements were based on the group average. Restriction of energy and protein reduced dry matter, crude protein, and total digestive nutrient intake for cows fed 100E+50P and 50E+100P. The lowest body weight was observed for cows fed 50E+100P, with no difference for body condition score. During the induction phase, MES "was" reduced by 9 percentage units. Cows fed 100E+100P recovered MES in the first days of the recovery phase, while 100E+50P slightly improved MES, and 50E+100P had a constant decrease in MES. Cows fed 100E+50P and 50E+100P produced, respectively, 3.6 and 5.9 kg less milk than those fed 100E+100P. The 50E+100P treatment exhibited the highest milk fat content and somatic cell score, along with the lowest milk lactose content. Protein content was higher in the 100E+100P treatment. Cows fed 50E+100P showed higher serum albumin levels compared with those on the 100E+100P treatment, not differing from the 100E+50P treatment. We concluded that the complete recovery of MES in cows with feed restrictions is possible only by supplying both the energy and protein requirements in the cows' diet. However, restricting energy intake poses a greater limitation on MES recovery compared with restricting protein.

Smell loss associated with SARS-CoV-2 is not clinically different from other viruses: a multicenter cohort study.

BACKGROUND: Although the COVID-19 pandemic has increased the prevalence of cases with olfactory loss, other respiratory viruses can also cause this condition. We aimed to compare the prevalence of acute SARS-CoV-2 infection and other respiratory viruses in patients with sudden smell loss, and to assess the impact of SARS-CoV-2 viral load and co-infection on olfactory symptoms. METHODS: Patients with sudden smell loss were recruited in a multicenter prospective cohort study in 15 hospitals in Brazil. Clinical questionnaire, Connecticut Chemosensory Clinical Research Center (CCCRC) olfactory test and nasopharyngeal swab to perform a PCR-based respiratory viral panel were collected at first visit (day 0) and 30 and 60 days after recruitment. RESULTS: 188 of 213 patients presented positive test result for SARS-CoV-2, among which 65 were co-infected with other respiratory viruses (e.g., rhinovirus, enterovirus, and parainfluenza). 25 had negative test results for SARS-CoV-2. Patients in both SARSCoV-2 and non-SARS-CoV-2 groups had objective anosmia (less than 2 points according to the psychophysical olfactory CCCRC) at day 0, with no significant difference between them. Both groups had significant smell scores improvement after 30 and 60 days, with no difference between them. Co-infection with other respiratory viruses, and SARS-CoV-2 viral load did not impact olfactory scores. CONCLUSION: Patients with sudden smell loss associated with SARS-CoV-2 and other respiratory viruses had similar presentation, with most participants initiating with anosmia, and total or near total recovery after 60 days. SARS-CoV-2 viral load and co-infections with other respiratory viruses were not associated with poorer olfactory outcomes.

Vacancy clustering effect on the electronic and transport properties of bilayer graphene nanoribbons.

Experimental realizations of two-dimensional materials are hardly free of structural defects such as e.g. vacancies, which, in turn, modify drastically its pristine physical defect-free properties. In this work, we explore effects due to point defect clustering on the electronic and transport properties of bilayer graphene nanoribbons, for AA and AB stacking and zigzag and armchair boundaries, by means of the tight-binding approach and scattering matrix formalism. Evident vacancy concentration signatures exhibiting a maximum amplitude and an universality regardless of the system size, stacking and boundary types, in the density of states around the zero-energy level are observed. Our results are explained via the coalescence analysis of the strong sizeable vacancy clustering effect in the system and the breaking of the inversion symmetry at high vacancy densities, demonstrating a similar density of states for two equivalent degrees of concentration disorder, below and above the maximum value.

Decisive points for pregnancy losses in beef cattle.

Beef cattle producers rely on each of their cows to produce a marketable calf each year to maintain a sustainable operation. Within the first month of gestation, pregnancy failures have been recorded to be upwards of 40-50%. From fertilisation to birth, there are numerous factors contributing to pregnancy failure. From the beginning of gestation oocyte competence is often a large factor impacting fertility as the dam contributes all mRNA for initial embryo development. Other factors contributing to early embryonic infertility include hormonal concentration and heat stress. After the embryo enters the uterus, it becomes critical for the uterus to be receptive to the developing conceptus. The embryo then begins to elongate and secrete interferon-tau to initiate maternal recognition of pregnancy; a requirement to establish and maintain bovine pregnancies. After a pregnancy completes these steps, placentation actively begins around day 22 of pregnancy and lasts until organogenesis. The fetal phase follows the embryonic phase where disease and/or toxins are often the cause of pregnancy failure at this period. However, fetal mortality has been reported to occur in less than 10% of pregnancies. Understanding of the many factors influencing infertility needs to be further investigated to increase pregnancy success in beef cattle.

Increasing the length of an estradiol with progesterone timed artificial insemination protocol with 2 controlled internal drug release devices improves pregnancy per artificial insemination in lactating dairy cows.

The objective of this study was to compare the effects of different lengths of ovulation synchronization protocols using 2 controlled internal drug release (CIDR) devices on ovarian dynamics and pregnancy outcomes in lactating dairy cows. Lactating Holstein cows (n = 1,979) were randomly assigned to receive timed artificial insemination (TAI; d 0) following 1 of 2 treatments: (1) 9-d protocol (n = 988; 9D) with 2 intravaginal devices containing 1.9 g of progesterone (CIDR) and 2.0 mg of estradiol benzoate on day -11; 25 mg (i.m.) of dinoprost tromethamine (PG) and withdrawal of 1 CIDR on d -4; 1.0 mg (i.m.) of estradiol cypionate, second CIDR withdrawal, and PG on d -2; and TAI on d 0 and (2) 10-d protocol (n = 991; 10D) with 2 CIDR and 2.0 mg of estradiol benzoate on d -12; 25 mg of PG and withdrawal of 1 CIDR on d -4; 1.0 mg of estradiol, second CIDR withdrawal, and PG on d -2; and TAI on d 0. There was no effect of protocol on estrus detection, whereas a greater percentage of cows from 10D had ovulated close to TAI [no corpus luteum (CL) at AI and a CL at d 7] versus cows assigned to 9D protocol. A protocol × heat stress (average cow temperature ≥39.1°C on day of AI and d 7) interaction was observed in a manner that pregnancy per AI (P/AI) was greater in non-heat-stressed 10D versus 9D cows, whereas P/AI did not differ when cows were under heat stress. Furthermore, 10D protocol did not increase P/AI when all cows that received AI were included in the analysis or in cows that ovulated near TAI. However, animals assigned to 9D without any event of heat stress had a reduced P/AI when compared with cows assigned to 10D without heat stress. A protocol × CL presence at the beginning of the protocol interaction was observed and cows with a CL at the beginning of the protocol had a greater P/AI in 10D versus 9D; meanwhile, in cows without a CL, no differences on P/AI were observed. The protocol × CL presence at the beginning of the protocol interaction on P/AI was also observed for cows that ovulated near TAI. A greater percentage of cows assigned to 9D had follicles of medium size (13-15.9 mm), and greater percentage of cows assigned to 10D had larger follicles (>16 mm). Increasing the length of an estradiol with progesterone-based ovulation synchronization protocol (10D vs. 9D) increased the proportion of cows with larger follicles (>16 mm) and increased P/AI in cows without heat stress and in cows with a CL at beginning of the protocol. Moreover, the 10D protocol increased the proportion of cows with ovulation near TAI, demonstrating the effectiveness of this protocol in improving the reproductive performance of lactating Holstein cows.

Virulence factors and antimicrobial resistance of Staphylococcus aureus isolated from the production process of Minas artisanal cheese from the region of Campo das Vertentes, Brazil.

Staphylococcus aureus is one of the main pathogens found in cheeses produced with raw milk, including Minas artisanal cheese from Brazil. However, information about S. aureus isolated from artisanal cheeses and its sources of production in small-scale dairies is very limited. We aimed to characterize the virulence factors of S. aureus isolated from raw milk, endogenous starter culture, Minas artisanal cheese, and cheese handlers from the region of Campo das Vertentes, Minas Gerais, Brazil. We identified the staphylococcal isolates by MALDI-TOF mass spectrometry. We evaluated biofilm production on Congo red agar and polystyrene plates. We used PCR to detect icaA, icaB, icaC, sea, seb, sec, sed, see, tsst-1, agr, and mecA. We evaluated the expression of staphylococcal toxin genes in PCR-positive staphylococcal isolates using quantitative reverse-transcription PCR, and we evaluated the production of these toxins and their hemolytic activity in vitro. We also evaluated the antimicrobial resistance profile of the staphylococcal isolates. For statistical analysis, we used cluster analysis, χ2 tests, and correspondence tests. We analyzed 76 staphylococcal isolates. According to PCR, 18.42, 18.42, 2.63, and 77.63% were positive for sea, tsst-1, sec, and agr, respectively. We found low expression of staphylococcal toxin genes according to quantitative reverse-transcription PCR, and only 2 staphylococcal isolates produced toxic shock syndrome toxins. A total of 43 staphylococcal isolates (56.58%) had hemolytic activity; 53 were biofilm-forming on Congo red agar (69.73%), and 62 on polystyrene plates (81.58%). None of the staphylococcal isolates expressed the mecA gene, and none presented a multi-drug resistance pattern. The highest resistance was observed for penicillin G (67.11%) in 51 isolates and for tetracycline (27.63%) in 21 isolates. The staphylococcal isolates we evaluated had toxigenic potential, with a higher prevalence of sea and tsst-1. Biofilm production was the main virulence factor of the studied bacteria. Six clusters were formed whose distribution frequencies differed for hemolytic activity, biofilm formation (qualitative and quantitative analyses), and resistance to penicillin, tetracycline, and erythromycin. These findings emphasize the need for effective measures to prevent staphylococcal food poisoning by limiting S. aureus growth and enterotoxin formation throughout the food production chain and the final product.

Protective device to reduce aerosol dispersion in dental clinics during the COVID-19 pandemic.

AIM: To describe the use of a new protective device to reduce aerosol dispersion in dental clinics during the COVID-19 pandemic. METHODOLOGY: The device consists of a rigid translucent acrylic structure (methyl polymethacrylate), adjusted to the dental chair, involving the patient's head, neck and chest. There is also a piping system to generate negative pressure, for aspiration and filtering of the air inside the device chamber. The operator works through small holes in the acrylic structure, to reduce contact with the microparticles arising from aerosols during dental procedures. Simulated dental procedures using a fluorescent dye in the water of the dental equipment were carried out, with and without the use of the device. The presence of the dye was analysed at various locations, such as on personal protective equipment (PPE), the dental chair and on the clinic floor. RESULTS: In the simulated dental procedure without the device, the dye was obvious on surgical gloves, aprons (waist, chest, legs, fists) and face shields, as well as on the dental chair (backrest, light reflector) and clinic floor. In the simulated dental procedure using the device, the dye was observed only on surgical gloves, apron (fists), inside the pipe system and internal walls of the acrylic chamber. There was a certain limitation of movement and visualization by the dentist whilst using the device. CONCLUSIONS: The present device is a low-cost complementary resource for use in conjunction with standard PPE, to reduce the transmission of SARS-CoV-2 in the dental setting. Further clinical trials should be carried out to test the efficacy of this device to reduce aerosol dispersion and the consequent vector of contamination, as well as the ergonomic impacts related to its use.

Assessment of gastric emptying of maltodextrin, coffee with milk and orange juice during labour at term using point of care ultrasound: a non-inferiority randomised clinical trial.

Labouring women have been shown to have slower gastric emptying than non-pregnant subjects, and this argument is sometimes used to recommend fasting guidelines such as nil-by-mouth during labour. We performed a parallel group, randomised non-inferiority trial, comparing gastric emptying of 450 ml isocalorically-adjusted maltodextrin, coffee with milk or pulp-free orange juice, with 18 women in each group. The women were initially fasted for 2 h for clear fluids, 6 h for a light meal and 8 h for a high fat or high protein meal. We performed gastric ultrasound in the semirecumbent-right lateral decubitus position. Gastric antral area was measured at baseline and at 5 min, 30 min, 60 min, 90 min and 120 min. Gastric emptying of maltodextrin was significantly faster than coffee with milk (p < 0.001) and orange juice (p < 0.001). There was no statistically significant difference between pulp-free orange juice and coffee with milk (p = 0.97). The estimated gastric residual volume was lower than baseline from 90 min after drinking maltodextrin. In labouring women, maltodextrin is cleared from the stomach faster than coffee with milk and orange juice. Gastric emptying depends on other factors besides the caloric load and volume of the drink.

Immunodetection of the toxic portion of Vip3A reveals differential temporal regulation of its secretion among Bacillus thuringiensis strains.

AIMS: To devise a protocol for heterologous expression and purification of a partial toxic portion of the Bacillus thuringiensis (Bt) vegetative insecticidal protein Vip3A and using it as an antigen for anti-Vip3A polyclonal antibody development. Also, to evaluate the regulation of Vip3A secretion into culture supernatants (SNs) of different Bt strains based on this antibody. METHODS AND RESULTS: A primer pair was designed to amplify partially the toxic portion of the vip3A gene from the HD125 strain. The amplicon was cloned in expressing vector to produce a ~35 kDa peptide, which was HPLC-purified prior to rabbit immunizations. The serum containing the polyclonal anti-Vip3A antibody demonstrated a detection sensitivity of 0·4 ng mm-2 for the antigen in slot-blot experiments. Seven Bt strains from different origins were assessed regarding their temporal secretion of Vip3A toxin. ELISA results showed a strain-specific temporal regulation of Vip3A secretion in culture for the temperate isolates, with no detection of the toxin for the tropical strains, even when the presence of the gene was confirmed by PCR and sequencing. CONCLUSIONS: Conformational variation in the toxic portion of Vip3A may explain lack of its detection in the tropical strains. Isolates from the same subspecies display physiological variability in proteins' secretion into culture SNs, which can affect screening procedures for more effective strains/toxins. SIGNIFICANCE AND IMPACT OF THE STUDY: Immunoassays based on the developed anti-Vip3A antibody can be useful in a variety of basic studies. This method can be also coupled with toxicity assays on target insects, for more efficient screening methods of novel Bt strains/toxins with biocontrol applicability.

Association between psychotropic medications and presence of sleep bruxism: A systematic review.

The purpose of this study was to systematically review the literature for studies that investigated the association between use of psychotropic medications and presence of sleep bruxism (SB). Observational studies were selected in a two-phase process. Searches were performed on six electronic databases, and a grey literature search was conducted on three databases. SB diagnosis was based on questionnaires or clinical examinations; no polysomnography examinations were performed. Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Analytical Cross-Sectional Studies. Overall quality of evidence was evaluated according to the Grading of Recommendations Assessment, Development and Evaluation criteria. Five analytical cross-sectional studies were included, evaluating antidepressants, anticonvulsants and psychostimulants. One study was judged as low risk of bias, three as moderate risk and one high risk. Antidepressants were evaluated in adult populations only; duloxetine (Odds Ratio [OR] = 2.16; 95% Confidence Interval [95% CI] = 1.12-4.17), paroxetine (OR = 3.63; 95% CI = 2.15-6.13) and venlafaxine (OR = 2.28; 95% CI = 1.34-3.86) were positively associated with SB risk. No increased odds of SB were observed considering use of citalopram, escitalopram, fluoxetine, mirtazapine and sertraline. With regard to anticonvulsants, only barbiturates were associated with SB in children (OR = 14.70; 95% CI = 1.85-116.90), while no increased odds were observed for benzodiazepine, carbamazepine and valproate. The only psychostimulant evaluated was methylphenidate, and an association with SB was observed in adolescents (OR = 1.67; 95% CI = 1.03-2.68). Findings from this SR suggested that medications such as duloxetine, paroxetine, venlafaxine, barbiturates and methylphenidate might be associated with SB; however, overall quality of evidence was considered very low, and therefore, caution is recommended.

In vitro anthelmintic and cytotoxic activities of extracts of Persea willdenovii Kosterm (Lauraceae).

This study describes the effects of extracts and fractions of Persea willdenovii leaves against goat gastrointestinal nematodes and their cytotoxicity on Vero cells. The in vitro ovicidal and larvicidal activities of the crude ethanolic, hexane, ethyl acetate (EAE), butanolic and residual hydroethanolic extracts were assessed through the inhibition of egg hatching and larval motility assays. The most active extract (EAE) was then fractionated by chromatography in an open column containing silica gel, to furnish six fractions (Fr1-Fr6), which were also tested. The cytotoxicity of active extracts and fractions was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and trypan blue exclusion assay. The EAE and two fractions (Fr1 and Fr2) showed inhibitory activity in the egg hatching of gastrointestinal nematodes of goats in a concentration-dependent manner. The effective concentrations for 50% inhibition (EC50) of egg hatching were 2.3, 0.12 and 2.94 mg/ml for EAE, Fr1 and Fr2, respectively. All extracts and fractions were not effective in inhibiting 50% of motility of infective larvae. EAE and Fr2 had IC50 values (50% inhibitory concentration) of 4.95 and 2.66 mg/ml, respectively. Fr1 showed a slight cytotoxic effect (cellular inviability <30%) only after 48 h of treatment (MTT test). Gas chromatography-mass spectrometry (GC-MS) analysis showed the presence of six fatty acid ethyl esters, a fatty acid methyl ester and a long-chain ketone in the most active fraction. These constituents identified in P. willdenovii can be related to the high ovicidal activity and relatively non-toxic effect of the extracts.

Immunoassay quantification using surface-enhanced fluorescence (SEF) tags.

Fluorescence-based immonoassays are widely used in several areas, ranging from basic biomedical research to disease diagnostics. A variety of new probes have been developed recently to address some limitations in typical assays performed with organic dyes. Ideally, new fluorescence tags that allow quantification with a low limit of detection are highly desired. In this work, the surface-enhanced fluorescence (SEF) phenomenon was explored in the development of tags for Immunoglobulin-M (IgM) detection. Shell-isolated gold nanoparticles (Au-SHINs) with 100 nm core size and a 10 nm silica shell were synthesized. These particles contain an outermost thin fluorescent layer of nile blue (NB) that was further coated by another 5 nm of silica (SEF tags). The outer silica shell was then functionalized with antibodies to allow the detection of IgM as in typical immunological sandwich assays. IgM concentrations down to the 10 ng mL-1 mark were successfully detected. A linear dependence between the average fluorescence intensity and the IgM concentration was found.

In silico modeling and characterization of phytoparasitic nematodes translationally-controlled tumor proteins.

Plant parasitic nematodes infect a wide range of hosts representing the largest source of biotic stress experienced by plants. Meloidogyne genus comprises the most important parasitic nematodes, also known as root-knot nematodes. These parasitic organisms obtain nutrients to support their development through complex interactions with their hosts. The translationally-controlled tumor protein (TCTP) is widely expressed in eukaryotic organisms, and is related to a great diversity of biological processes such as calcium binding, cell proliferation and growth, pluripotency, regulation of apoptosis, microtubules stabilization, and histamine release. TCTP has been identified in the secretions of plant-parasitic nematodes, and may play a role in suppressing the plant immunity and programmed cell, hence promoting nematode parasitism. Our results revealed a high conservation of the evaluated protein sequences and little variation in their physico-chemical characteristics, such as isoelectric points and hidropathicity. Phylogenetic analysis also revealed the presence of three main groups of TCTPs, corresponding to plant parasitic, animal parasitic and free-living nematodes. Six plant parasitic TCTPs tertiary structure models were generated by homology modeling. The constructed models were highly similar and most of the structural variations occurred outside the characterized functional domains. To our knowledge, these are the first theoretical models of plant parasitic nematodes TCTPs and these results may provide a theoretical basis for future studies of host plant resistance to nematode infection.

Prevalence of human papillomavirus, Chlamydia trachomatis, and Trichomonas vaginalis infections in Amazonian women with normal and abnormal cytology.

Sexually transmitted infections are an important cause of morbidity among sexually active women worldwide, and have been implicated as cofactors in the pathogenesis of cervical cancer. We investigated the prevalence of human papillomavirus (HPV), Chlamydia trachomatis (CT), and Trichomonas vaginalis (TV), and accessed the diversity of HPV in women with normal and abnormal cytology in Manaus, Brazil. We used polymerase chain reaction and HPV genotyping by direct sequencing. The chi-square test was used to calculate the absolute and relative frequencies of the categorical variables, and Fisher's test was used when P < 0.05. The level of significance was set at 5%. All statistical analyses were performed using R 2.9.0. There were statistically significant differences in age (P = 0.0395), education level (P = 0.0131), sexual partners (P = 0.0211), condom use (P = 0.0039), marital status (P < 0.0001), and pregnancy (P = 0.0003) between the normal and abnormal groups. HPV DNA was found in 36.56 and 93.88% of subjects in the normal and abnormal groups, respectively. A total of 19 genotypes were detected; HPV16 was the most common, followed by HPV58. The percentages of TV and CT DNA were 18.04 and 9.02% in the normal group, respectively. The percentages of HPV/TV and HPV/CT coinfection were 12.5% each in women with normal cytology. These findings improve our understanding of HPV, CT, and TV, and the distribution of HPV types, which may be relevant to vaccination strategies for protecting women from the north of Brazil from cervical cancers and precancerous lesions.

Biofilm and toxin profile: A phenotypic and genotypic characterization of coagulase-negative staphylococci isolated from human bloodstream infections.

Coagulase-negative staphylococci (CNS) represent one of the most prevalent microorganisms in nosocomial infections worldwide, nevertheless little is known about their pathogenicity features. Thus, our aim was to characterize virulence aspects of CNS isolated from patients with bloodstream infections assisted in hospitals of Belo Horizonte, MG, Brazil. Strains were identified using bioMérieuxVitek® and for biofilm production evaluation, Congo Red Agar (CRA) and polystyrene plates were used. PCR was applied to detect icaA, icaB, icaC, atlE, sea, sec, sed, tsst-1 and agr. For statistical analyses were used hierarchical cluster, chi-square test and correspondence. 59 strains were analyzed, being S. haemolyticus the most prevalent. On CRA, 96.5% were biofilm producer, whereas on polystyrene plate, 100% showed adhesion at different times evaluated. Regarding genotypic analyses, 15.2%, 38.9%, 8.4%, 49.1%, 76.2%, 23.7%, 1.6%, 30.5% and 38.9% were positive for icaA, icaB, icaC, atlE, sea, sec, sed, tsst-1 and agr, respectively. Six clusters were formed and frequency distributions of agr, atlE, icaA, icaB, sea, sec, tsst-1 differed (P < 0.001). In conclusion, all strains were biofilm producer, with high prevalence of atlE, and had potential of toxin production, with high prevalence of sea. According to the group-analyses, icaB showed relationship with the strong adherence in samples.

Central and peripheral fat body mass have a protective effect on osteopenia or osteoporosis in adults and elderly?

UNLABELLED: This cross-sectional study involves randomly selected men aged 50 to 99 years and postmenopausal women. Either central fat mass or peripheral fat mass were associated to osteoporosis or osteopenia independently from fat-free body mass and other confounding factors. INTRODUCTION: Obesity and osteoporosis are public health problems that probably share common pathophysiological mechanisms. The question if body fat mass, central or peripheral, is protective or harmful for osteoporosis or osteopenia is not completely resolved. This study aims to investigate the association between osteoporosis or osteopenia, and fat body mass (central and peripheral) independently from fat-free body mass, in men aged 50 to 99 years old and postmenopausal women randomly selected in the community. METHODS: This is a cross-sectional investigation with a random sample of registered population in Niterói Family Doctor Program (FDP), State of Rio de Janeiro, Brazil. Bone mineral density (BMD) and fat-free mass were assessed by dual X-ray absorptiometry (DXA). RESULTS: There was statistically significant bivariate association between bone loss with gender, age, skin color, alcohol consumption at risk dose, use of thiazide, fat-free body mass, and fat body mass (central and peripheral). In the multiple analysis of fat-free body mass, central and peripheral fat body mass showed an independent and protective effect on the presence of osteoporosis or osteopenia (p value <0.001). CONCLUSION: Since both obesity and osteoporosis are public health problems worldwide, strategies aimed at preventing both conditions should be encouraged during aging.

In silico comparative analysis of tylenchid nematode pectate lyases.

Phytoparasitic nematodes can infect a wide range of crop plants, and cause billions of dollars of agricultural losses each year. These parasites represent the largest source of biotic stress experienced by plants. The order Tylenchida comprises the most important parasitic nematodes, particularly the root-knot and cyst nematodes. These parasitic organisms obtain nutrients to support their development through complex interactions with their hosts. Plant-parasitic nematodes secrete a mixture of cell-wall degrading enzymes to facilitate migration through the plant root. Enzymes are secreted that degrade the principal cell-wall components, cellulose, hemi-cellulose, or pectin. Pectate lyases are important parasitism factors in plant-parasitic nematodes. These enzymes degrade polygalacturonic acid, which is a fundamental constituent of pectin of host cell walls. Thus, pectate lyases permit the penetration and colonization of plant host cells by parasites. Here, we analyzed 22 pectate lyase protein sequences from tylenchid nematode species. Our results revealed great variation in the isoelectric points of pectate lyases, and groups of acidic and alkaline proteins that may have distinct enzymatic activities were identified. Phylogenetic analysis also revealed the presence of two main groups of pectate lyases with distinct chemical properties. Seven conserved motifs were identified, but only five were present in all sequences. Results of the molecular docking analysis revealed differences in the predicted interaction sites in the pectate lyases from the two groups. These results may provide a theoretical basis for future studies of host plant resistance to nematode infection.

Genetic diversity and morphological characterization of half-sib families of Heliconia bihai L., H. chartacea Lane ex Barreiros, and H. wagneriana Peterson.

The Neotropical Heliconia genus contains highly diversified plants and up to 220 species have been reported from the north of Mexico to the South of Brazil. Heliconia are cultivated as ornamental garden plants and as cut flowers. All species can be propagated by seeds or vegetatively, through rhizomes. Depending on the species, an individual plant can spread and form large clonal populations. H. bihai L., H. chartacea Lane ex Barreiros, and H. wagneriana Petersen are among the most cultivated Heliconia species. However, they still have undesirable characteristics that could be improved for the international market. This study aimed to characterize 15 half-sib families originating from commercial cultivations, by morphological and molecular markers. The genetic diversity (HE), considering all individuals of the three species was 0.103. For H. bihai half-sib families, the value of HE was 0.242, showing high genetic diversity. The HE value for H. chartacea was 0.068, indicating low genetic diversity. All individuals of H. wagneriana showed the same band patterns, suggesting that the two parental plants were propagated vegetatively from the same plant and may have undergone some endogamic crossings. These results showed that molecular characterization can differentiate individuals closely related as half-siblings for H. bihai and H. chartacea, despite the low variation observed with morphological descriptors. The high genetic diversity observed in H. bihai half-sibling genotypes can provide valuable resources for breeding programs.