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Lipids are among the organic substances that can work as biosignatures, indicating life in an environment. We present an experimental investigation concerning analysis of lipids from a microbial source deposited on the Mars Global Simulant (MGS-1) regolith by geomatrix-assisted laser desorption/ionization-mass spectrometry (GALDI-MS). Our results indicate that lipids from intact microbial cells of a black yeast strain can be detected in these mimetic samples of Martian soil. These lipid molecules are predominantly associated with the occurrence of adducts in the GALDI-MS spectra. The results can be helpful in the planning of future planetary missions.
Sex selection through sperm sorting offers advantages in regards selection pressure in high-producing livestock. However, the sex-sorting process results in sperm membrane and DNA damage that ultimately decrease fertility. We hypothesized that given the role of protamines in DNA packaging, protamine deficiency could account, at least partially, for the DNA damage observed following sperm sex sorting. To test this, we compared protamine status between unsexed and sexed spermatozoa from two bulls using the fluorochrome chromomycin A3 (CMA3) and flow cytometry. Then, we assessed embryo development following in vitro fertilization (IVF) using the same sperm treatments. Overall, sperm protamination was not different between sexed and unsexed semen. However, one of the two bulls displayed higher rates of protamine deficiency for both unsexed and sexed semen (P < 0.05). Moreover, unsexed semen from this bull yielded lower blastocyst (P < 0.05) and blastocyst hatching rates than unsexed sperm from the other bull. CMA3-positive staining was negatively correlated with cleavage (R2 85.1, P = 0.003) and blastocyst hatching (R2 87.6, P = 0.006) rates in unsexed semen. In conclusion, while the sex-sorting process had no effect on sperm protamine content, we observed a bull effect for sperm protamination, which correlated to embryo development rates following IVF.
Accurate estimates of methane (CH4) production by cattle in different contexts are essential to developing mitigation strategies in different regions. We aimed to: (i) compile a database of CH4 emissions from Brazilian cattle studies, (ii) evaluate prediction precision and accuracy of extant proposed equations for cattle and (iii) develop specialized equations for predicting CH4 emissions from cattle in tropical conditions. Data of nutrient intake, diet composition and CH4 emissions were compiled from in vivo studies using open-circuit respiratory chambers, SF6 technique or the GreenFeed® system. A final dataset containing intake, diet composition, digestibility and CH4 emissions (677 individual animal observations, 40 treatment means) obtained from 38 studies conducted in Brazil was used. The dataset was divided into three groups: all animals (GEN), lactating dairy cows (LAC) and growing cattle and non-lactating dairy cows (GCNL). A total of 54 prediction equations available in the literature were evaluated. A total of 96 multiple linear models were developed for predicting CH4 production (MJ/day). The predictor variables were DM intake (DMI), gross energy (GE) intake, BW, DMI as proportion of BW, NDF concentration, ether extract (EE) concentration, dietary proportion of concentrate and GE digestibility. Model selection criteria were significance (P < 0.05) and variance inflation factor lower than three for all predictors. Each model performance was evaluated by leave-one-out cross-validation. The Intergovernmental Panel on Climate Change (2006) Tier 2 method performed better for GEN and GCNL than LAC and overpredicted CH4 production for all datasets. Increasing complexity of the newly developed models resulted in greater performance. The GCNL had a greater number of equations with expanded possibilities to correct for diet characteristics such as EE and NDF concentrations and dietary proportion of concentrate. For the LAC dataset, equations based on intake and animal characteristics were developed. The equations developed in the present study can be useful for accurate and precise estimation of CH4 emissions from cattle in tropical conditions. These equations could improve accuracy of greenhouse gas inventories for tropical countries. The results provide a better understanding of the dietary and animal characteristics that influence the production of enteric CH4 in tropical production systems.
Medicinal plants have been the focus of several studies due to their nematicide properties which can be used to control nematodes in sheep. No study has examined the morphological effects of Cymbopogon citratus on nematodes. Thus, this study evaluated the chemical composition, nematicidal activity and effects of C. citratus extracts on the morphology of eggs and infective larvae (L3) of sheep. Aqueous and methanolic extracts and fractions of C. citratus were obtained and analysed in vitro. The C. citratus extracts were effective against Haemonchus spp. and Trichostrongylus spp. larvae and eggs. Ten fractions were obtained from C. citratus, six of which had high ovicidal activity at 1000 μg mL−1, and two fractions had high activity at all tested concentrations. The phytochemical analysis identified the presence of compounds such as terpenoids, various ketones, esters, and fatty acids. The ultrastructural analysis showed deformations of the cuticle and wilting along the body of the nematodes at all concentrations. The muscular layer, intestinal cells and the mitochondria profile showed damage compared to the typical pattern. Ultra-thin sections of eggs treated with methanolic fractions of C. citratus presented modifications. This study showed the biological activity and effects of C. citratus on the gastrointestinal nematodes in sheep.
Housekeeping genes (HKG) are paramount for accurate gene expression analysis during preimplantation development. Markedly, quantitative reverse transcription polymerase chain reaction (RT-qPCR) in ovine embryos currently lacks HKGs. Therefore, we tested 11 HKGs for RT-qPCR normalization during ovine parthenogenetic preimplantation development. Seven HKGs reached the qPCR efficiency threshold (97.20–105.96%), with correlation coefficients ranging from −0.922 to −0.998 and slopes from −3.22 to −3.59. GeNorm ranked glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and TATA-binding protein (TBP) as the best HKG pair, while H3 histone, family 3A (H3F3A) was the third HKG. Relative gene expression was measured for zinc finger protein X-linked (ZFX) and developmental pluripotency-associated 3 (DPPA3) transcripts during ovine parthenogenetic preimplantation development. ZFX did not show any transcript abundance fluctuation among oocytes, cleavage-stage embryos, and morulae. DPPA3 transcript abundance was also similar among all developmental stages, therefore suggesting that it may not display a maternal gene expression profile. In silico analysis of ovine DPPA3 mRNA and protein showed high conservation to bovine orthologues. However, DPPA3 orthologues differed in regulatory motifs. In conclusion, GAPDH, TBP and H3F3A are stable HKGs in ovine parthenogenetic embryos and allow accurate RT-qPCR-based gene expression analysis.
The diagnostic boundaries of social anxiety disorder (SAD) are still controversial and recent evidence suggests that the condition could be better understood as a continuum of severity, rather than a strictly circumscribed entity. Current neuroanatomical theories on SAD support the involvement of limbic structures in its pathophysiology, with an emphasis on the amygdala. Thus, the objective of this study was to investigate the hypothesis of volumetric alterations in the amygdala of subjects in different points of the social anxiety spectrum.
The sample consisted of patients with generalized SAD (n=17), subthreshold SAD (increased social anxiety without avoidance; n=13), and healthy controls (n=15). Participants underwent structural magnetic resonance scans and the volume of the bilateral amygdala was manually determined.
Significantly greater volumes of bilateral amygdala were found in socially anxious individuals. Amygdala volumes of subthreshold SAD participants fell between the values found for generalized SAD and healthy controls.
Individuals suffering from SAD have greater amygdala volumes compared to controls and this difference seems to be in agreement with the theoretical conception of SAD as a severity continuum and not as a circumscribed nosological entity.
Depression is the psychiatric co-morbidity most commonly associated with Parkinson's disease (PD). However, depression is often under-diagnosed and under-recognized and the affected patients seldom receive treatment for this psychiatric disorder. The objective of the present study was to determine the prevalence of major depression among Brazilian patients with a diagnosis of PD.
The study was conducted at the movement disorders outpatient clinic of the University Hospital, Faculty of Medicine of Ribeirão Preto. A total of 111 consecutive patients with a diagnosis of PD were selected and independently interviewed using the SCID-IV-CV (DSM-IV). Patients with dementia associated with PD were excluded.
Patient age ranged from 24 to 85 years (mean: 61.2 + 12.7 years). Fifty-eight of the 102 patients (52.3%) were females and 53 (47.7%) were males. The current prevalence of depression was 26.1% (29) and the lifetime was 57.7% (64). Regarding gender, the current prevalence of depression was 15.1% (9) for males and 36.2% (21) for females, with the difference being statistically significant (p<0.01). The lifetime prevalence of depression was 33.4% (23) for males and 70.7% (41) for females (p<0.01).
The high prevalence of major depression among patients with PD and the predominance of women detected in this study are comparable to the rates observed in studies conducted in other countries. Strategies for an early diagnosis and adequate treatment appear to be necessary and opportune in order to improve the quality of life of the patients and to prevent possible complications such as suicide.
The diagnostic frontiers of social anxiety disorder (SAD) are still controversial, since it could be described as part of a continuum of severity rather than as a disorder based on an arbitrary threshold with qualitative distinctions. The present study aims to investigate possible differences among subjects along the social anxiety spectrum using the Simulated Public Speaking Test (SPST), an experimental model of human anxiety. Afterwards, the anticipatory measures of SPST among groups were correlated with different volume of gray matter areas by MRI using the voxel-based morphometry method.
We evaluated patients with generalized SAD (n=25), subjects with subclinical SAD (with fear of a social situation without avoidance or impairment; n=14) and healthy controls (n=22).
The subjective SPST findings showed that avoidance and functioning impairment were due to a negative self-evaluation in SPST and not to the level of anxiety experienced. When all groups were pooled together, there was a positive correlation between levels of anxiety experienced and the volume of the right amygdala. The negative self-evaluation of performance in the SPST was associated with a reduction in the volume of the anterior cingulated complex (ACC) only in the SAD group.
These results suggest that the association between anxiety and amygdala volume may be a part of a continuum of social anxiety. However, the correlation between self-evaluation of performance with reduced ACC volume only in the SAD group does not support the idea that this association may be also part of a continuum.
Panic disorder (PD) is a common and debilitating anxiety disorder. Recent neuroanatomical theories of PD propose an extensive involvement of limbic system in pathophysiology of this condition. In fact, several structural and functional neuroimaging studies have shown changes in limbic structures, such as hippocampus in PD patients. Despite this, no prior studies have examined hippocampal neurochemistry in this disorder. The current study used proton magnetic resonance spectroscopy imaging (1H-MRSI) to examine possible neurochemical abnormalities in hippocampus in PD patients.
Twenty-five patients meeting the DSM-IV criteria for PD and eighteen psychiatrically healthy controls were investigated. The subjects were paired based on gender, age, years of education, handedness, and socioeconomic level. N-acetylaspartate (NAA, a putative marker of neuronal viability) and choline (Cho, involved in the synthesis and degradation of cell membranes) levels were quantified relative to creatine (Cr, which is thought to be relatively stable among individuals and in most brain areas) in both right and left hippocampus.
Compared with controls, panic patients demonstrated significantly lower NAA/Cr in the left hippocampus. No other difference was detected.
This result is consistent with the previous findings of hippocampal alterations in PD and provides the first neurochemical suggesting of involvement of this structure in the disorder.
The Social Anxiety Disorder (SAD) is a highly incapacitating condition that can cause considerable subjective suffering, with a negative impact on psychosocial functioning. However, few data are available in the literature about the influence of SAD severity and of SAD subtypes or the presence of comorbidities on psychosocial functioning, and the possible extent of this impairment in individuals with subclinical signs and symptoms.
The study consisted of the evaluation of psychosocial functioning using the Disability Profile (DP) in 355 volunteers, all of them college students who had been diagnosed in a previous study as SAD (N=141), Controls (N=92) or Subclinical (N=122), the last ones being defined as having unreasonable fear of a social situation but not fulfilling the criteria of avoidance or functional/occupational impairment due to this fear.
The groups were balanced regarding age, sex and socioeconomic level.
The SAD group had higher scores than the other two groups in all domains of DP, both on a lifetime basis and during the last two weeks. Subjects with subclinical SAD presented intermediate values.
The impairment of psychosocial functioning was also significantly related to the severity of the disorder. Regarding subtype, generalized SAD causes more harm, and the presence of comorbidities is associated with greater impairment of psychosocial functioning in each group.
The impairment of psychosocial functioning progressively increases along the spectrum of social anxiety. Further studies are needed to evaluate the consequences of this association.
Most patients with Social Anxiety Disorder (SAD) present other psychiatric disorders. The lifetime prevalence of comorbidities has been reported to range from 52% to 92% in epidemiological studies. There is some evidence showing that the frequency of comorbidities varies according to subtype and severity of SAD and those subjects with subclinical SAD present intermediate values.
The study consisted of the evaluation of psychiatric comorbidities in 355 volunteers, all of them college students who had been diagnosed as SAD (N=141), Controls (N=92) or Subclinical (N=122) in a previous study. The groups were balanced regarding age, sex and socioeconomic level. Three interviewing psychiatrists, blind to the group to which the volunteers belonged, applied the SCID for the DSM-IV.
The rate of comorbidity with other psychiatric disorders was 71.6% in the SAD group and 50% in subjects with Subclinical SAD and differed significantly from the Controls (28.7%). These results confirm in a Brazilian sample of college students the results of other epidemiological and clinical studies on the existence of high levels of lifetime comorbidity in SAD.
The presence of comorbidities increased progressively according to SAD subtype and severity, with the rates for subclinical subjects being intermediate, with lower values than subjects with circumscribed SAD or with mild cases of SAD, but significantly higher than control.
The rates of psychiatric comorbidity increase progressively along the spectrum of social anxiety. Further studies are needed to determine the consequences of this association.
Social Anxiety Disorder (SAD) is a psychiatric co-morbidity commonly related to Parkinson's disease (PD). However, the real nature of this association is still unknown. The objective of the present study was to determine the prevalence of SAD in patients with a diagnosis of PD.
Eighty-seven consecutive patients with a diagnosis of PD and no associated dementia were evaluated at a movement disorder outpatient clinic. The patients were independently interviewed using the SCID-IV for DSM-IV.
Patient age ranged from 24 to 85 years (mean: 60.7 years) (+13.2). Forty-five patients (51.7%) were women and 42 (48.3%) were men. The lifelong prevalence of SAD was 32.2%. However, only 16.1% presented this anxiety disorder before the beginning of PD. The prevalence of SAD with onset after PD, i.e., secondary to a movement disorder, was 16.1%, with no sex differences in SAD prevalence among PD patients.
The high rate of SAD among PD patients detected in the present study (32.1%) is comparable to those reported in other countries. However, the prevalence of patients who presented SAD before the onset of PD (16.1%) was similar to that reported for the general population. Thus, the present results suggest that the high rates of SAD among PD patients reported in the literature are due to afraid to be judged in a negative manner in public due to their tremors and other aspects of PD, rather than being related to a specific neurobiological process occurring in this movement disorder.
The association between Mitral Valve Prolapse (MVP) and anxiety disorders, particularly Panic disorder (PD) and Social Anxiety disorder (SAD), attracted considerable interest in the 1980 and 1990 decades but the published results were not sufficient to definitely establish or to exclude an association between MVP and PD or SAD, with prevalences ranging from 0 to 57%.
According to a recent literature review on this topic, there are no studies about this possible association using current MVP criteria.
The study consisted of echocardiographic evaluation of 232 volunteers previously diagnosed with SAD (N=126), PD (N=41) or Control (N=65). The exams were performed by two cardiologists specialized in echocardiography who were blind to the psychiatric diagnosis of the participants.
There were no statistical differences between groups in MVP prevalence (SAD=4.0%, PD=2.4% and Control=0.0%), with values similar to the prevalence currently estimated for the normal population (2-4%). When the data were evaluated using the M-mode, the method used in most of the previous studies but currently considered of questionable validity, the prevalence was higher in the SAD group (8.7%) compared to control (0.0%).
Regarding the other morphological characteristics of the mitral valve, no significant differences were detected between groups in terms of the presence of mitral insufficiency, mean valve thickness and mean valvar dislocation in any two-dimensional echocardiographic view.
If any relationship does actually exist among SAD, PD and MVP, it could be said that it is infrequent and that it mainly occurs in subjects with minor variants of MVP.
Large ground-dwelling Neotropical gamebirds are highly threatened by habitat loss and hunting, but conservationists rarely attempt to distinguish between these two threats in the management of populations. We used three different types of species records to determine the status (i.e. persistence level) of the Endangered red-billed curassow Crax blumenbachii in 14 forest remnants in north-east Brazil, as either persistent, precarious or extirpated. We related these persistence levels to variables measured in a 2-km buffer radius, including variables associated with habitat quality (proportion of forest cover, length of rivers, patch density, distance from rivers) and hunting pressure (proportion of cacao agroforests and farmlands, length of roads, total area occupied by settlements, distance from roads and from settlements). Curassows were more persistent in forest patches located (1) more distant from settlements, (2) in landscapes with few settlements, (3) in landscapes with a high incidence of roads, (4) in a mosaic with a high proportion of forest, shaded cacao agroforest and farmland, and (5) more distant from other forest patches. Hunting pressure potentially exerts more influence on persistence than habitat quality: (1) hunting pressure submodels had a higher explanatory power than habitat quality submodels, (2) final models comprised four hunting pressure variables but only two habitat quality variables, and (3) hunting pressure variables appeared in all models whereas habitat quality variables appeared in only one final model. If hunting pressure is driving declines in curassows, regions with low human presence and a high proportion of forest cover are recommended for establishing new reserves.
An experiment was conducted to evaluate: (1) the effects of ensiling maize or sorghum grains after reconstitution on readily soluble fraction (a), potentially degradable fraction in the rumen (b) and rate constant for degradation of b (c) of dry matter (DM), organic matter (OM) and starch (STA); and (2) an appropriate incubation time for in situ or in vitro procedures to estimate in vivo digestibility. Four rumen-cannulated Nellore bulls (body weight = 262 ± 19.6 kg) distributed in a 4 × 4 Latin square were used. Diets were based on dry ground maize (DGM); or dry ground sorghum (DGS); or reconstituted ground maize silage; or reconstituted ground sorghum silage. In vitro and in situ incubations of the individual grains and diets were simultaneously performed with in vivo digestibility. In general, reconstituted grains and diets based on reconstituted grains presented greater (P < 0.05) fraction a and lower (P < 0.05) fraction b of DM, OM and STA compared to dry grains and diets based on dry grain. However, the magnitude of response of the reconstitution and ensiling process on DM and OM degradability parameter was greater for maize than that for sorghum. Moreover, no differences (P > 0.05) were observed between DGM- and DGS-based diets for c estimates. The results suggest that the reconstitution process promotes grains protein matrix breakdown increasing STA availability. The incubation times required for in vivo digestibility estimations of DM, OM and STA are 24 h for in situ and 36 h for in vitro procedures.
The objective of this meta-analysis study was to develop and validate equations estimated from in situ and in vitro methods to predict in vivo ruminal digestibility of organic matter (OM) of beef cattle diets. The database was composed of individual data of 23 diets from six experiments. Information collected from these studies was: in vivo digestibility and degradation parameters of OM calculated from in situ and in vitro incubations. The values of estimated times for the in situ and in vitro incubations to access in vivo digestibility of OM, and differences between degradation at 24, 48 and 72 h (in situ and in vitro) and in vivo digestibility were analysed in a model that included the fixed effects of forage neutral detergent fibre level. Thereafter, a multiple stepwise regression was carried out using OM digestibility as a dependent variable and degradation parameters (A = water-soluble fraction; B = potentially degradable water-insoluble fraction; and kd = degradation rate of fraction B) as independent variables. Equation validation was performed using data from a seventh experiment that have the same methods than previous studies. Stepwise regression results showed that the kd contributed significantly in most of the algorithms derived to predict in vivo digestibility. Validation analysis showed that equations developed from both in vitro and in situ incubations accurately estimated the in vivo digestibility of OM (P > 0.05). Our results suggest that equations developed to estimate OM digestibility showed both precision and accuracy; however, in situ method presented better results than in vitro.
The current study evaluated the effects of dietary roughage:concentrate (R:C) ratios and water supply on the carcass characteristics and yield of lambs. Forty Santa Inês crossbred lambs with an average body weight (BW) of 19 ± 2.8 kg were evaluated in a completely randomized design with a 2 × 2 factorial arrangement consisting of two proportions of roughage and concentrate (30:70 and 70:30) and two levels of water supply (ad libitum and restricted to 0.5). The animals were slaughtered at an average weight of 28 ± 31 kg. Centesimal composition, colour parameters (L*, a* and b*), shear force, cooking losses and pH were determined on the Longissimus lumborum muscle. There was no interaction effect between the R:C ratio and water supply on the evaluated variables. Total BW gain, average daily gain and final BW were affected by water restriction and R:C ratio. Water restriction reduced total BW gain, average daily gain and final BW. No effect of water restriction was detected on slaughter weight, centesimal composition, colour variations, shear force, pH, weight or yield of carcass. No effect of water restriction and diets was observed on the cuts, except for neck weight. Carcass weight and yield were affected by the R:C ratios. Restricting the water supply to 0.5 does not affect the carcass weight or yield of Santa Inês crossbred lambs or their meat quality characteristics (centesimal composition, colour, shear force and pH measurements). A higher proportion of concentrate in the diet results in heavier hot and cold carcass weights.
Fibropapillomatosis (FP) can be an important conservation threat to green sea turtles (Chelonia mydas) due to its widespread distribution and complex aetiology. Thus, understanding the impacts of FP in sea turtle populations is a research priority towards conservation efforts. The body condition index (BCI), based on straight carapace length (SCL) and body mass (BM), is an accurate indicator of body-nutritional condition that can be used in routine green turtle health evaluations. This study aimed to compare BCI in FP-free (N = 369) and FP-affected (N = 518) green turtles from Brazilian feeding areas. Body condition indices were evaluated in terms of the South-west Atlantic Fibropapillomatosis Score – FPSSWA (mild, moderate and severe), study sites (five Brazilian states), origin (intentional capture, fishery, stranding and afloat) and sex (when known). Curved and straight carapace lengths, and body mass were recorded in order to calculate BCI. Statistical analysis revealed significant differences in BCI among green turtles from different study areas (P = 0.02), and lower BCI values in FP-free than in FP-positive individuals (P < 0.0001). With regards to origin, the highest BCI was found in the intentional capture group (N = 245; 1.47 ± 0.16), followed by fishery (N = 180; 1.46 ± 0.20). Analysis according to sex revealed a higher mean BCI among females than males (P < 0.017). This study provides relevant data on the health and nutritional status of green turtles along the Brazilian coast, in important feeding areas for this species.
The aim of the present study was to evaluate the association between depression and SSRI monotherapy and frailty both baseline and prospectively in older adults.
Prospective cohort study, 12-month follow-up.
Geriatric outpatient clinic in São Paulo, Brazil.
A total of 811 elderly adults aged 60 or older.
Depression was diagnosed as follows: (1) a diagnosis of major depression disorder (MDD) according to DSM-5; or (2) an incomplete diagnosis of MDD, referred to as minor or subsyndromic depression, plus Geriatric Depression Scale 15-itens ≥ 6 points, and social or functional impairment secondary to depressive symptoms and observed by relatives. Frailty evaluation was performed through the FRAIL questionnaire, which is a self-rated scale. Trained investigators blinded to the baseline assessment conducted telephone calls to evaluate frailty after 12-month follow-up. The association between depression and the use of SSRI with frailty was estimated through a generalized estimating equation adjusted for age, gender, total drugs, and number of comorbidities.
Depression with SSRI use was associated with frailty at baseline (OR 2.82, 95% CI = 1.69–4.69) and after 12 months (OR 2.75, 95% CI = 1.84–4.11). Additionally, depression with SSRI monotherapy was also associated with FRAIL subdomains Physical Performance (OR 1.99, 95% CI = 1.29–3.07) and Health Status (OR 4.64, 95% CI = 2.11–10.21). SSRI use, without significant depressive symptoms, was associated with subdomain Health Status (OR 1.52, 95% CI = 1.04–2.23).
It appears that depression with SSRI is associated to frailty, and this association cannot be explained only by antidepressant use.