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1.
Environ Res ; 201: 111566, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34181917

RESUMO

Cyanobacterial molecular biology can identify pathways that affect the adhesion and settlement of biofouling organisms and, consequently, obtain novel antifouling strategies for marine applications. Proteomic analyses can provide an essential understanding of how cyanobacteria adapt to different environmental settings. However, only a few qualitative studies have been performed in some cyanobacterial strains. Considering the limited knowledge about protein expression in cyanobacteria in different growing conditions, a quantitative proteomic analysis by LC-MS/MS of biofilm cells from a filamentous strain was performed. Biofilms were also analysed through standard methodologies for following cyanobacterial biofilm development. Biofilms were formed on glass and perspex at two relevant hydrodynamic conditions for marine environments (average shear rates of 4 s-1 and 40 s-1). Biofilm development was higher at 4 s-1 and no significant differences were found between surfaces. Proteomic analysis identified 546 proteins and 41 were differentially expressed. Differences in protein expression were more noticeable between biofilms formed on glass and perspex at 4 s-1. When comparing biofilms formed on different surfaces, results suggest that biofilm development may be related to the expression of several proteins like a beta-propeller domain-containing protein, chaperone DnaK, SLH domain-containing proteins, an OMF family outer membrane protein, and/or additional uncharacterized proteins. Regarding the hydrodynamic effect, biofilm development can be related to SOD enzyme expression, to proteins related to photosynthetic processes and to a set of uncharacterized proteins with calcium binding domains, disordered proteins, and others involved in electron transfer activity. Studies that combine distinct approaches are essential for finding new targets for antibiofilm agents. The characterisation performed in this work provides new insights into how shear rate and surface affect cyanobacterial biofilm development and how cyanobacteria adapt to these different environmental settings from a macroscopic standpoint to a proteomics context.


Assuntos
Cianobactérias , Proteômica , Biofilmes , Cromatografia Líquida , Espectrometria de Massas em Tandem
2.
Osteoporos Int ; 28(5): 1675-1683, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28204954

RESUMO

Results from bone biopsy and high-resolution peripheral quantitative computed tomography (HR-pQCT) were compared in 31 CKD patients. There was an agreement mainly for cortical compartment that may represent a perspective on the fracture risk assessment. HR-pQCT also provided some clues on the turnover status, which warrants further studies. INTRODUCTION: Chronic kidney disease (CKD) patients are at high risk of bone disease. Although bone biopsy is considered the best method to evaluate bone disease, it is expensive and not always available. Here we have compared, for the first time, data obtained from bone biopsy and HR-pQCT in a sample of CKD patients on dialysis. METHODS: HR-pQCT and dual-energy X-ray absorptiometry (DXA) were performed in 31 CKD patients (30 on dialysis). Biopsies were analyzed by quantitative histomorphometry, and classified according to TMV. RESULTS: We have found an inverse correlation between radius cortical density measured by HR-pQCT, with serum, as well as histomorphometric bone remodeling markers. Trabecular density and BV/TV measured through HR-pQCT in the distal radius correlated with trabecular and mineralized trabecular bone volume. Trabecular number, separation, and thickness obtained from HR-pQCT and from bone biopsy correlated with each other. Patients with cortical porosity on bone histomorphometry presented lower cortical density at the distal radius. Cortical density at radius was higher while bone alkaline phosphatase was lower in patients with low turnover. Combined, these parameters could identify the turnover status better than individually. CONCLUSIONS: There was an agreement between HR-pQCT and bone biopsy parameters, particularly in cortical compartment, which may point to a new perspective on the fracture risk assessment for CKD patients. Besides classical bone resorption markers, HR-pQCT provided some clues on the turnover status by measurements of cortical density at radius, although the significance of this finding warrants further studies.


Assuntos
Osteoporose/etiologia , Insuficiência Renal Crônica/complicações , Absorciometria de Fóton/métodos , Adulto , Biópsia , Densidade Óssea/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Osteoporose/patologia , Osteoporose/fisiopatologia , Hormônio Paratireóideo/sangue , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/patologia , Rádio (Anatomia)/fisiopatologia , Diálise Renal , Insuficiência Renal Crônica/terapia , Reprodutibilidade dos Testes , Tíbia/diagnóstico por imagem , Tíbia/patologia , Tíbia/fisiopatologia , Tomografia Computadorizada por Raios X/métodos
3.
Asian-Australas J Anim Sci ; 27(9): 1293-302, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25178373

RESUMO

The aim of study was to determine the energy requirements for maintenance and growth of forty-one Saanen, intact male kids with initial body weight (BW) of 5.12±0.19 kg. The baseline (BL) group consisted of eight kids averaging 5.46±0.18 kg BW. An intermediate group consisted of six kids, fed for ad libitum intake, that were slaughtered when they reached an average BW of 12.9±0.29 kg. The remaining kids (n = 27) were randomly allocated into nine slaughter groups (blocks) of three animals distributed among three amounts of dry matter intake (DMI; ad libitum and restricted to 70% or 40% of ad libitum intake). Animals in a group were slaughtered when the ad libitum-treatment kid in the group reached 20 kg BW. In a digestibility trial, 21 kids (same animals of the comparative slaughter) were housed in metabolic cages and used in a completely randomized design to evaluate the energetic value of the diet at different feed intake levels. The net energy for maintenance (NEm) was 417 kJ/kg(0.75) of empty BW (EBW)/d, while the metabolizable energy for maintenance (MEm) was 657 kJ/kg(0.75) of EBW/d. The efficiency of ME use for NE maintenance (km) was 0.64. Body fat content varied from 59.91 to 92.02 g/kg of EBW while body energy content varied from 6.37 to 7.76 MJ/kg of EBW, respectively, for 5 and 20 kg of EBW. The net energy for growth (NEg) ranged from 7.4 to 9.0 MJ/kg of empty weight gain by day at 5 and 20 kg BW, respectively. This study indicated that the energy requirements in goats were lower than previously published requirements for growing dairy goats.

4.
Chemosphere ; 307(Pt 1): 135583, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35792207

RESUMO

Ultraviolet radiation (UV) and triclosan (TCS) affect the early development of marine fish; however, the corresponding molecular mechanisms are still not fully understood. Therefore, this work aims to study the effects of the single and combined exposure to these stressors during the thyroid-regulated metamorphosis of the flatfish Solea senegalensis. Sub-lethal exposure (5.89 kJ m-2 UV and/or 0.546 and 1.090 mg L-1 TCS for 48 h) was performed at the beginning of metamorphosis (13 days after hatching, dah), followed by a period in clean media until complete metamorphosis (24 dah). Malformations, metamorphosis progression, length, behavior and the expression of thyroid axis-related genes were studied. TCS induced malformations, decreased swimming performance, and induced metamorphosis acceleration at 15 dah, followed by a significant metamorphosis delay. Such effects were more noticeable in the presence of UV. The down-regulation of five thyroid axis-related genes occurred after exposure to TCS (15 dah), and after 9 days in clean media two genes were still down-regulated. UV exposure increased the effect of TCS by further down-regulating gene expression immediately after the exposure. Since several effects persisted after the period in clean media, implications of these stressors (mainly TCS) on the ecological performance of the species are suggested.


Assuntos
Linguados , Triclosan , Animais , Linguados/genética , Linguados/metabolismo , Larva , Metamorfose Biológica , Triclosan/metabolismo , Raios Ultravioleta
5.
Meat Sci ; 186: 108734, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35033833

RESUMO

Forty crossbred (Santa Ines × Dorper) male lambs were used to investigate the effect of dietary buriti oil (BOIL) intake on meat quality, fatty acid (FA) composition and sensory attributes. A completely randomized design with five BOIL intake levels (0, 12, 24, 36 and 48 g/kg DM) was used. Increasing dietary BOIL intake linearly reduced the DMI, slaughter weight, cooking loss, shear force, yellowness, 16:0, c9-18:1 FA concentrations, and the delta-9-desaturase activity index computed using c9-16:1 and 16:0 as product and substrate pair, cis-MUFA and Æ©MUFA/Æ©SFA ratio of lamb meat (P ≤ 0.05); however, increasing dietary BOIL intake quadratically increased the energy intake, lipid content and linearly increased the total FA intake, chroma, collagen, total BI, 18:0, 20:3n-6 concentration and sensory attributes of lamb meat (P ≤ 0.05), without affecting health indexes regarding fat consumption. BOIL addition at levels above 24 g/kg DM in lamb diet reduces growth, however, improves tenderness, flavor and "goat" aroma intensity and slightly changes meat FA levels, promoting better acceptance by panelists.


Assuntos
Gorduras Insaturadas na Dieta , Carne Vermelha , Ração Animal/análise , Animais , Carotenoides , Dieta/veterinária , Ácidos Graxos , Masculino , Carne/análise , Óleos de Plantas , Carne Vermelha/análise , Ovinos
6.
Chemosphere ; 235: 885-899, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31284137

RESUMO

Harmful effects of triclosan (TCS) have been reported on several organisms; however, effects on early life stages of marine vertebrates are limited. Therefore, the objective of this work was to assess the effects of TCS during early development of the flatfish Solea senegalensis after initial characterization of cholinesterases (ChEs) and determination of selected biochemical markers baseline levels. Characterization of ChEs and determination of biochemical markers baseline levels of cholinergic activity, energy metabolism and oxidative stress were analysed in sole at 3 days after hatching (dah) and at the onset and end of metamorphosis. To assess TCS effects, fish were exposed during 96h to 30-500 µg L-1 TCS until 3 dah. Fish at 13 dah were exposed during 48h to 200-1,500 µg L-1 TCS and maintained until complete metamorphosis. Effects on survival, malformations, length, metamorphosis progression and biochemical markers were evaluated. The main ChE active form present in sole early life stages is acetylcholinesterase and baseline levels of oxidative stress and energy metabolism biomarkers changed according to fish developmental stage. Triclosan induced malformations (EC50 = 180 µg L-1 at 3 dah), decreased growth (95 µg L-1 at 3 dah; 548 µg L-1 at 24 dah) and affected metamorphosis progression (391 µg L-1 at 17 dah). Impairment of antioxidant system was observed, with TCS affecting catalase at the end of metamorphosis test, however, no oxidative damage on lipids was detected. Glutathione S-transferase was the most sensitive endpoint during early larval test (LOEC = 30 µg L-1). Exposure to TCS affected S. senegalensis at individual and sub-individual levels, both at early larval stage and during the critical period of metamorphosis.


Assuntos
Linguados/embriologia , Larva/efeitos dos fármacos , Metamorfose Biológica/efeitos dos fármacos , Triclosan/toxicidade , Acetilcolinesterase/metabolismo , Animais , Catalase/metabolismo , Colinesterases/metabolismo , Metabolismo Energético/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Triclosan/metabolismo
7.
Sci Total Environ ; 628-629: 1395-1404, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30045559

RESUMO

The inclusion of organic UV filters in personal care products (PCPs) has increased in recent years. 4-Methylbenzylidene camphor (4MBC) is one of the most used UV filters, and thus it is commonly found in aquatic ecosystems, with proved negative effects on aquatic organisms. Effects on early life stages of marine vertebrates are largely unknown. Therefore, the main goal of this work was to evaluate 4MBC effects on Senegalese sole (Solea Senegalensis Kaup, 1858) larvae at different levels of biological organization. S. senegalensis were exposed to increasing concentrations of 4MBC from egg stage until 96 h. Mortality, growth, malformations, behaviour and biochemical responses, including enzymatic biomarkers were studied. The exposure to 4MBC until 96 h post-fertilization (hpf) induced mortality and malformations in a dose-response manner. Besides, reduced growth with increasing concentrations was observed. The exposure to 4MBC also caused alterations on behaviour, including overall lower swimming time during light and dark periods. Biomarker alterations caused by 4MBC included imbalance of neurotransmission related endpoints (increased acetylcholinesterase activity) and decreased activity of enzymes related to anaerobic metabolism (lower cellular lactate dehydrogenase activity) at the lower concentrations tested. Furthermore, our results suggest that 4MBC do not induce oxidative stress in S. senegalensis larvae, since catalase and lipid peroxidation levels were not significantly altered by 4MBC. S. senegalensis revealed to be a good model species for vertebrate animal testing in the marine environment. Sub-lethal concentrations of 4MBC induced toxic effects at all organizational levels. Swimming behaviour was a sensitive endpoint and showed that exposure to 4MBC causes impairment on response to light stimulus which is possibly linked with the observed imbalances on cholinesterase activity in larvae. Conservation concerns along distribution range of S. senegalensis should consider that increasing levels of UV filters in marine environment might have impact on the ecology of the species.


Assuntos
Cânfora/análogos & derivados , Protetores Solares/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cânfora/toxicidade , Linguados/fisiologia , Testes de Toxicidade
9.
J Anim Sci ; 95(1): 395-406, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28177375

RESUMO

This study evaluated the effects of replacing ground corn with buriti oil ( L.) on feed intake and digestibility and on the production, composition, fatty acid profile and sensory characteristics of goat milk. A double Latin square (4 × 4) was used; eight goats were distributed in a completely randomized design. The square comprised four periods and four buriti oil concentration (0.00; 1.50; 3.00 and 4.50% of total DM) replacing corn. Intakes of DM, CP, NDF, ADF, non-fibrous carboydrates (NFC) and TDN were not affected by the replacement of corn with oil in the diet. However, lipids intake was increased ( < 0.01) by 100% in the diet of goats with 4.50% oil inclusion, as total DM. DM and CP digestibility were similar between the buriti oil concentrations. However, lipid digestibility increased linearly ( = 0.01) and may have contributed to a quadratic reduction in NDF digestibility ( = 0.01) and a linear reduction of NFC ( = 0.04) with buriti oil content in the goat feed. Goat milk production, corrected production and chemical composition were not influenced by the concentration of buriti oil replacement; however, milk fat concentration ( = 0.04) and feed efficiency ( < 0.01) increased linearly with the amount of buriti oil in the diet. There was a linear reduction on hypercholesterolemic SFA such as C12:0 ( < 0.01) and C14:0 ( < 0.01) as well as the atherogenic index (AI; < 0.01) with buriti oil inclusion in goat's diet. In contrast, the fatty acids C18:0 ( < 0.01) and C18:1 9 ( < 0.01) increased linearly in the milk of goats that were fed with buriti oil. However, CLA ( < 0.01) varied quadratically; the maximum production of 0.62 g/100 g of fat was observed when using 1.50% buriti oil. The sensory characteristics of the milk were not changed ( > 0.05) by the replacement of corn with buriti oil in the goats' diet. It is recommended to replace corn with buriti oil in goat feed by up to 4.5% of total DM, resulting in improved feed efficiency and milk fat without affecting production; this recommendation satisfies the minimum requirements of the industry and preserves the organoleptic characteristics of the milk and its acceptability for human consumption. In addition, buriti oil replacing ground corn by up to 4.5% DM in the diet of lactating goats decrease medium-chain SFA which are hypercholesterolemic and increase the concentrations of the C18:19, CLA and DFA in goat milk fat, helping to protect against cardiovascular disease.


Assuntos
Ração Animal/análise , Carotenoides/metabolismo , Dieta/veterinária , Ácidos Graxos/química , Cabras/metabolismo , Leite/química , Óleos de Plantas/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Digestão , Ácidos Graxos/metabolismo , Comportamento Alimentar , Feminino , Lactação/efeitos dos fármacos , Lipídeos/análise , Zea mays
10.
Contraception ; 48(1): 29-35, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8403903

RESUMO

The experience of 670 diaphragm users from three Brazilian clinics was retrospectively reviewed. Most of the subjects (441) followed the traditional method (TM) of using the diaphragm, only at the time of sexual intercourse and with spermicide. One third (215) used the diaphragm continuously (CU), without spermicide, removing it only at the time of their daily shower to wash it, with immediate re-insertion. The total pregnancy rate was 7.0 per 100 women-years for the whole group. Patient and total failure rate were significantly lower in the CU (0.6 and 2.8), in comparison with the TM sub-group (6.5 and 9.8). The discontinuation rate for urinary infection or other medical reasons was not greater in the CU group. Logistic regression analysis, including age, parity, number of abortions and of living children, years of schooling, whether living with a partner, presence of mild cystocele or retroverted uterus, and form of use of diaphragm (TM or CU), showed that only the TM of diaphragm use was positively associated to patients' and total failure rate.


PIP: In Brazil, a retrospective review of clinical records of diaphragm users from the Sexuality and Health Women's Collective in central Sao Paulo, the family planning clinic at the State University of Campinas, and a private practice in Belo Horizonte was performed to compare data on 215 women continuously using it without spermicide, except to clean it during a shower, with data on 441 women using it with spermicide only during sexual intercourse to determine diaphragm effectiveness. The patients' failure rate stood considerably higher among women using the diaphragm with spermicide (6.5 vs. 0.61; p .05). The method failure rate was just slightly higher in the diaphragm with spermicide users' group (3.53 vs. 2.2). 71.47% of all women continued use for 12 months, especially women continuously using the diaphragm without spermicide (84.84 vs. 63.28%; p .05). Women who used the diaphragm with spermicide were more likely to discontinue for vaginal discharge and for other medical and personal reasons than were those who continuously used it without spermicide (p .05). They were also more likely to be lost to follow up (16.4% vs. 6.43%; p .05). The logistic regression analysis indicated that diaphragm with spermicide use was positively linked to patients' and total failure (p = .042). These findings suggested that the messiness of diaphragm use with spermicide, its interference with sexual intercourse, and perhaps spermicide cost contributed to its high discontinuation and failure rates. The findings should raise interest in identifying means to improve acceptance of and use effectiveness of the diaphragm.


Assuntos
Dispositivos Anticoncepcionais Femininos , Adulto , Feminino , Humanos , Análise de Regressão , Estudos Retrospectivos , Espermicidas
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