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Methicillin-resistant Staphylococcus (MRS) has been associated with neonatal infections, with colonization of the anovaginal tract being the main source of vertical transmission. The COVID-19 pandemic has altered the frequency of antibiotic usage, potentially contributing to changes in the dynamics of bacterial agents colonizing humans. Here we determined MRS colonization rates among pregnant individuals attending a single maternity in Rio de Janeiro, Brazil before (January 2019-March 2020) and during (May 2020-March 2021) the COVID-19 pandemic. Anovaginal samples (n = 806 [521 samples before and 285 during the pandemic]) were streaked onto chromogenic media. Colonies were identified by MALDI-TOF MS. Detection of mecA gene and SCCmec typing were assessed by PCR and antimicrobial susceptibility testing was done according to CLSI guidelines. After the onset of the pandemic, MRS colonization rates increased significantly (p < 0.05) from 8.6% (45) to 54.7% (156). Overall, 215 (26.6%) MRS isolates were detected, of which S. haemolyticus was the most prevalent species (MRSH, 84.2%; 181 isolates). SCCmec type V was the most frequent among MRS (63.3%; 136), and 31.6% (68) of MRS strains had a non-typeable SCCmec, due to new combinations of ccr and mecA complexes. Among MRS strains, 41.9% (90) were resistant to at least 3 different classes of antimicrobial agents, and 60% (54) of them were S. haemolyticus harboring SCCmec V. MRS colonization rates and the emergence of multidrug-resistant variants detected in this study indicate the need for continuing surveillance of this important pathogen within maternal and child populations.
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COVID-19 , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Humanos , Femenino , Embarazo , COVID-19/epidemiología , COVID-19/virología , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Adulto , Brasil/epidemiología , Complicaciones Infecciosas del Embarazo/microbiología , Complicaciones Infecciosas del Embarazo/epidemiología , Antibacterianos/farmacología , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Pandemias , Vagina/microbiologíaRESUMEN
BACKGROUND: Transfers of nursing home (NH) residents to the emergency department (ED) is frequent. Our main objective was to assess the cost of care pathways 6 months before and after the transfer to the emergency department among NH residents, according to the type of transfer (i.e. appropriate or inappropriate). METHODS: This was a part of an observational, multicenter, case-control study: the Factors associated with INappropriate transfer to the Emergency department among nursing home residents (FINE) study. Sixteen public hospitals of the former Midi-Pyrénées region participated in recruitment, in 2016. During the inclusion period, all NH residents arriving at the ED were included. A pluri-disciplinary team categorized each transfer to the ED into 2 groups: appropriate or inappropriate. Direct medical and nonmedical costs were assessed from the French Health Insurance (FHI) perspective. Healthcare resources were retrospectively gathered from the FHI database and valued using the tariffs reimbursed by the FHI. Costs were recorded over a 6-month period before and after transfer to the ED. Other variables were used for analysis: sex, age, Charlson score, season, death and presence inside the NH of a coordinating physician or a geriatric nursing assistant. RESULTS: Among the 1037 patients initially included in the FINE study, 616 who were listed in the FHI database were included in this economic study. Among them, 132 (21.4%) had an inappropriate transfer to the ED. In the 6 months before ED transfer, total direct costs on average amounted to 8,145 vs. 6,493 in the inappropriate and appropriate transfer groups, respectively. In the 6 months after ED transfer, they amounted on average to 9,050 vs. 12,094. CONCLUSIONS: Total costs on average are higher after transfer to the ED, but there is no significant increase in healthcare expenditure with inappropriate ED transfer. Support for NH staff and better pathways of care could be necessary to reduce healthcare expenditures in NH residents. TRIAL REGISTRATION: clinicaltrials.gov, NCT02677272.
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Vías Clínicas , Casas de Salud , Anciano , Humanos , Estudios de Casos y Controles , Servicio de Urgencia en Hospital , Transferencia de Pacientes/métodos , Estudios RetrospectivosRESUMEN
We describe here the design, synthesis, physicochemical properties, and hepatitis B antiviral activity of new 2'-O-alkyl ribonucleotide N3'âP5' phosphoramidate (2'-O-alkyl-NPO) and (thio)-phosphoramidite (2'-O-alkyl-NPS) oligonucleotide analogs. Oligonucleotides with different 2'-O-alkyl modifications such as 2'-O-methyl, -O-ethyl, -O-allyl, and -O-methoxyethyl combined with 3'-amino sugar-phosphate backbone were synthesized and evaluated. These molecules form stable duplexes with complementary DNA and RNA strands. They show an increase in duplex melting temperatures of up to 2.5°C and 4°C per linkage, respectively, compared to unmodified DNA. The results agree with predominantly C3'-endo sugar pucker conformation. Moreover, 2'-O-alkyl phosphoramidites demonstrate higher hydrolytic stability at pH 5.5 than 2'-deoxy NPOs. In addition, the relative lipophilicity of the 2'-O-alkyl-NPO and NPS oligonucleotides is higher than that of their 3'-O- counterparts. The 2'-O-alkyl-NPS oligonucleotides were evaluated as antisense (ASO) compounds in vitro and in vivo using Hepatitis B virus as a model system. Subcutaneous delivery of GalNAc conjugated 2'-O-MOE-NPS gapmers demonstrated higher activity than the 3'-O-containing 2'-O-MOE counterpart. The properties of 2'-O-alkyl-NPS constructs make them attractive candidates as ASO suitable for further evaluation and development.
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Oligonucleótidos Antisentido , Oligonucleótidos , Oligonucleótidos/farmacología , Oligonucleótidos/química , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/farmacología , Ácidos Fosfóricos/farmacología , Ácidos Fosfóricos/química , Amidas/farmacología , Amidas/químicaRESUMEN
Neural circuit function is shaped both by the cell types that comprise the circuit and the connections between those cell types 1 . Neural cell types have previously been defined by morphology 2, 3 , electrophysiology 4, 5 , transcriptomic expression 6-8 , connectivity 9-13 , or even a combination of such modalities 14-16 . More recently, the Patch-seq technique has enabled the characterization of morphology (M), electrophysiology (E), and transcriptomic (T) properties from individual cells 17-20 . Using this technique, these properties were integrated to define 28, inhibitory multimodal, MET-types in mouse primary visual cortex 21 . It is unknown how these MET-types connect within the broader cortical circuitry however. Here we show that we can predict the MET-type identity of inhibitory cells within a large-scale electron microscopy (EM) dataset and these MET-types have distinct ultrastructural features and synapse connectivity patterns. We found that EM Martinotti cells, a well defined morphological cell type 22, 23 known to be Somatostatin positive (Sst+) 24, 25 , were successfully predicted to belong to Sst+ MET-types. Each identified MET-type had distinct axon myelination patterns and synapsed onto specific excitatory targets. Our results demonstrate that morphological features can be used to link cell type identities across imaging modalities, which enables further comparison of connectivity in relation to transcriptomic or electrophysiological properties. Furthermore, our results show that MET-types have distinct connectivity patterns, supporting the use of MET-types and connectivity to meaningfully define cell types.
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Pain is a multidimensional experience. Physiotherapy has attempted to enhance earlier biomedical approaches to patient care through approaches like the 'biopsychosocial' model. Nevertheless, physiotherapy continues to focus on biomedical and/or behavioural aspects of care. We critically investigated how physiotherapists attend to human (psychosocial, emotional, existential, and moral) aspects of low back pain care. We co-analysed ethnographic data with researchers, patients, and physiotherapists using concepts of conforming, tinkering and abandoning 'scripts'. Data included observations of 28 physiotherapy interactions between 26 patients and 10 physiotherapists and 7 researcher-clinician dialogues. Analysis suggests when conforming to scripts, clinicians have difficulty recognising and responding to emotions; time pressure limited clinicians focus, and a biological focus often distracted from psychosocial aspects of people's back pain experiences. In contrast, tinkering with or abandoning scripts allowed space to broaden the focus. Drawing from theorists such as Butler (1999) and Gibson et al. (2020) our analysis contributes to health sociology, arguing that 'tinkering' with or 'abandoning' scripts can foster more humanistic, flexible and reflexive approaches to care. Although health sociologists have explored tinkering, abandoning is new; within physiotherapy, it encapsulates being able to respond with agility to non-physical elements of care without constraint from traditional ways of thinking and doing.
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Dolor de la Región Lumbar , Fisioterapeutas , Humanos , Dolor de la Región Lumbar/terapia , Dolor de la Región Lumbar/psicología , Fisioterapeutas/psicología , Actitud del Personal de Salud , Investigación Cualitativa , Relaciones Profesional-PacienteRESUMEN
PURPOSE: To explore how uncertainty plays out in low back pain (LBP) care and investigate how clinicians manage accompanying emotions/tensions. MATERIALS AND METHODS: We conducted ethnographic observations of clinical encounters in a private physiotherapy practice and a public multidisciplinary pain clinic. Our qualitative reflexive thematic analysis involved abductive thematic principles informed by Fox and Katz (medical uncertainty) and Ahmed (emotions). RESULTS: We identified three themes. (1) Sources of uncertainty: both patients and clinicians expressed uncertainty during clinical encounters (e.g., causes of LBP, mismatch between imaging findings and presentation). Such uncertainty was often accompanied by emotions - anger, tiredness, frustration. (2) Neglecting complexity: clinicians often attempted to decrease uncertainty and associated emotions by providing narrow answers to questions about LBP. At times, clinicians' denial of uncertainty also appeared to deny patients the right to make informed decisions about treatments. (3) Attending to uncertainty?: clinicians attended to uncertainty through logical reasoning, reassurance, acknowledgement, personalising care, shifting power, adjusting language and disclosing risks. CONCLUSIONS: Uncertainty pervades LBP care and is often accompanied by emotions, emphasising the need for a healthcare culture that recognises the emotional dimensions of patient-clinician interactions and prepares clinicians and patients to be more accepting of, and clearly communicate about, uncertainty.IMPLICATIONS FOR REHABILITATIONUncertainty pervades LBP care and is often accompanied by emotions.Neglecting complexity in LBP care may compromise person-centred care.Acknowledging uncertainty can enhance communication, balance patient-clinician relationships and address human aspects of care.
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Dolor de la Región Lumbar , Humanos , Incertidumbre , Dolor de la Región Lumbar/terapia , Dolor de la Región Lumbar/psicología , Antropología Cultural , Atención Dirigida al PacienteRESUMEN
Introduction: The expansion of knowledge about head and neck cancer can provide greater care and the ability to identify risk factors and symptoms of the disease, as well as the incorporation of healthy habits. The younger these concepts are sedimented, the better results will be, making society healthier and more aware. Objective: To assess knowledge about head and neck cancer among adolescents from private schools, aged between 13 and 22 years. Methods: 200 questionnaires were applied among students, about the profile of adolescents and their knowledge about head and neck neoplasms, treatment, and teaching in schools on this topic. The results were analyzed both quantitatively and qualitatively. Results: Only 55 students (29.9%) identified HPV as a risk factor for the disease. 137 students (74.5%) identified the brain as an organ treated by head and neck surgery. As for the therapeutic strategies used for the treatment of neoplasms in the region, only 67 students (36.4%) are aware. On the topic of teaching in schools, 153 students (83.1%) relate to some deficiency in the approach and learning. Conclusion: Knowledge about head and neck cancer is insufficient. It is necessary to introduce in the curriculum basic cancer education in biology classes. The expansion of acquirements about cancer can provide better care and the ability to identify risk factors, initial signs, and symptoms of the disease, as well as the incorporation of healthy habits in families because these students can propagate valid information in their environment.
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Dog-mediated rabies kills tens of thousands of people each year in India, representing one third of the estimated global rabies burden. Whilst the World Health Organization (WHO), World Organization for Animal Health (OIE) and the Food and Agriculture Organization of the United Nations (FAO) have set a target for global dog-mediated human rabies elimination by 2030, examples of large-scale dog vaccination programs demonstrating elimination remain limited in Africa and Asia. We describe the development of a data-driven rabies elimination program from 2013 to 2019 in Goa State, India, culminating in human rabies elimination and a 92% reduction in monthly canine rabies cases. Smartphone technology enabled systematic spatial direction of remote teams to vaccinate over 95,000 dogs at 70% vaccination coverage, and rabies education teams to reach 150,000 children annually. An estimated 2249 disability-adjusted life years (DALYs) were averted over the program period at 526 USD per DALY, making the intervention 'very cost-effective' by WHO definitions. This One Health program demonstrates that human rabies elimination is achievable at the state level in India.
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Enfermedades de los Perros , Salud Única , Rabia , Animales , Análisis Costo-Beneficio , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/prevención & control , Perros , Humanos , India/epidemiología , Rabia/epidemiología , Rabia/prevención & control , Rabia/veterinariaRESUMEN
Despite the existence of a prophylactic vaccine against hepatitis B virus (HBV), chronic hepatitis B virus (CHB) infection remains the leading cause of cirrhosis and liver cancer in developing countries. Because HBV persistence is associated with insufficient host immune responses to the infection, development of an immunomodulator as a component of therapeutic vaccination may become an important strategy for treatment CHB. In the present study, we aimed to design a novel immunomodulator with the capacity to subvert immune tolerance to HBV. We developed a lymphoid organ-targeting immunomodulator by conjugating a naturally occurring, lipophilic molecule, α-tocopherol, to a potent CpG oligonucleotide adjuvant pharmacophore. This approach resulted in preferential trafficking of the α-tocopherol-conjugated oligonucleotide to lymphoid organs where it was internalized by antigen-presenting cells (APCs). Moreover, we show that conjugation of the oligonucleotides to α-tocopherol results in micelle-like structure formation, which improved cellular internalization and enhanced immunomodulatory properties of the conjugates. In a mouse model of chronic HBV infection, targeting CpG oligonucleotide to lymphoid organs induced strong cellular and humoral immune responses that resulted in sustained control of the virus. Given the potency and tolerability of an α-tocopherol-conjugated CpG oligonucleotide, this modality could potentially be broadly applied for therapeutic vaccine development.
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A functional cure of chronic hepatitis B requires eliminating the hepatitis B virus (HBV)-encoded surface antigen (HBsAg), which can suppress immune responses. STOPS are phosphorothioated single-stranded oligonucleotides containing novel chemistries that significantly reduce HBsAgs produced by HBV-infected liver cells. The STOPS molecule ALG-10000 functions inside cells to reduce the levels of multiple HBV-encoded molecules. However, it does not bind HBV molecules. An affinity resin coupled with ALG-10000 was found to bind several proteins from liver cells harboring replicating HBV. Silencing RNAs targeting host factors SRSF1, HNRNPA2B1, GRP78 (HspA5), RPLP1, and RPLP2 reduced HBsAg levels and other HBV molecules that are concomitantly reduced by STOPS. Host proteins RPLP1/RPLP2 and GRP78 function in the translation of membrane proteins, protein folding, and degradation. ALG-10000 and the knockdowns of RPLP1/2 and GRP78 decreased the levels of HBsAg and increased their ubiquitination and proteasome degradation. GRP78, RPLP1, and RPLP2 affected HBsAg production only when HBsAg was expressed with HBV regulatory sequences, suggesting that HBV has evolved to engage with these STOPS-interacting molecules. The STOPS inhibition of HBsAg levels in HBV-infected cells occurs by sequestering cellular proteins needed for proper expression and folding of HBsAg.
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Up to half of ICU survivors, many of whom were premorbidly well, will have residual functional and/or cognitive impairment and be vulnerable to future health problems. Frailty describes vulnerability to poor resolution of homeostasis after a stressor event but it is not clear whether the vulnerability seen after ICU correlates with clinical measures of frailty. In clinical practice, the scales most commonly used in critically ill patients are based on the assessment of severity and survival. Identification and monitoring of frailty in the ICU may be an alternative or complimentary approach, particularly if it helps explain vulnerability during the recovery and rehabilitation period. The purpose of this review is to discuss the use of tools to assess frailty status in the critically ill, and consider their importance in clinical practice. Amongst these, we consider biomarkers with potential to identify patients at greater or lesser risk of developing post-ICU vulnerability.
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Enfermedad Crítica , Fragilidad/diagnóstico , Gravedad del Paciente , Biomarcadores/análisis , HumanosRESUMEN
BACKGROUND: To date, no curative treatment is available for Alzheimer's disease (AD). Therefore, efforts should focus on prevention strategies to improve the efficiency of healthcare systems. OBJECTIVE: Our aim was to assess the cost-effectiveness of three preventive strategies for AD compared to a placebo. DESIGN: The Multidomain Alzheimer Preventive Trial (MAPT) study was a multicenter, randomized, placebo-controlled superiority trial with four parallel groups, including three intervention groups (one group with Multidomain Intervention (MI) plus a placebo, one group with Polyunsaturated Fatty Acids (PFA), one group with a combination of PFA and MI) and one placebo group. SETTING: Participants were recruited and included in 13 memory centers in France and Monaco. PARTICIPANTS: Community-dwelling subject aged 70 years and older were followed during 3 years. INTERVENTIONS: We used data from the MAPT study which aims to test the efficacy of a MI along PFA, the MI plus a placebo, PFA alone, or a placebo alone. MEASUREMENT: Direct medical and non-medical costs were calculated from a payer's perspective during the 3 years of follow-up. The base case incremental Cost-Effectiveness Ratio (ICER) represents the cost per improved cognitive Z-score point. Sensitivity analyses were performed using different interpretation of the effectiveness criteria. RESULTS: Analyses were conducted on 1,525 participants. The ICER at year 3 that compares the MI + PFA and the MI alone to the placebo amounted to 21,443 and 21,543 respectively, per improved Z score point. PFA alone amounted to 111,720 per improved Z score point. CONCLUSION: Our study shows that ICERS of PFA combined with MI and MI alone amounted to 21,443 and 21,543 respectively per improved Z score point compared to the placebo and are below the WTP of 50,000 while the ICER of PFA alone amounted to 111,720 per improved Z score point. This information may help decision makers and serve as a basis for the implementation of a lifetime decision analytic model.
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Enfermedad de Alzheimer , Cognición/fisiología , Análisis Costo-Beneficio/economía , Ácidos Docosahexaenoicos/administración & dosificación , Ejercicio Físico/fisiología , Anciano , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/prevención & control , Femenino , Francia , Humanos , Vida Independiente , Masculino , Mónaco , Proyectos de InvestigaciónRESUMEN
One of the main problems that remain in the implant industry is poor osseointegration due to bioinertness of implants. In order to promote bioactivity, calcium (Ca), phosphorus (P) and strontium (Sr) were incorporated into a TiO2 porous layer produced by micro-arc oxidation. Ca and P as bioactive elements are already well reported in the literature, however, the knowledge of the effect of Sr is still limited. In the present work, the effect of various amounts of Sr was evaluated and the morphology, chemical composition and crystal structure of the oxide layer were investigated. Furthermore, in vitro studies were carried out using human osteoblast-like cells. The oxide layer formed showed a triplex structure, where higher incorporation of Sr increased Ca/P ratio, amount of rutile and promoted the formation of SrTiO3 compound. Biological tests revealed that lower concentrations of Sr did not compromise initial cell adhesion neither viability and interestingly improved mineralization. However, higher concentration of Sr (and consequent higher amount of rutile) showed to induce collagen secretion but with compromised mineralization, possibly due to a delayed mineralization process or induced precipitation of deficient hydroxyapatite. Ca-P-TiO2 porous layer with less concentration of Sr seems to be an ideal candidate for bone implants.
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Materiales Biocompatibles Revestidos , Estroncio , Humanos , Oseointegración , Propiedades de Superficie , TitanioRESUMEN
Esophageal cancer (EC) is an aggressive disease, presenting two main histological subtypes: adenocarcinoma (EAC) and squamous cell carcinoma (ESCC). The two EC subtypes widely differ concerning virtually all factors. ESCC development is mainly associated with tobacco and alcohol abuse, whereas obesity and chronic gastroesophageal reflux disease (GERD) are important risk factors not only for EAC, but also for for Barrett's esophagus (BE), an intestinal metaplasia that precedes EAC. Obesity triggers ectopic lipid droplets (LD) accumulation in non-adipose tissues. LD are organelles involved in cell metabolism, signaling, proliferation and production of inflammatory mediators. Therefore, the aim of this work was to investigate LD occurrence and role in EC. This study shows progressive LD levels increase along EAC development, in esophageal samples from non-obese through obese individuals, as well as BE, and EAC patients, whereas no significant changes were observed in ESCC samples, when compared to non-tumor samples. Additionally, in order to mimic BE and EAC risk factors exposure, a non-tumor esophageal cell line was incubated with oleic acid (OA) and acidified medium and/or deoxycholic acid (DCA), revealing a significant increment in LD amount as well as in COX-2 and CXCL-8 expression, and in IL-8 secretion. Further, COX-2 expression and LD amount presented a significant positive correlation and were detected co-localized in EAC, but not in ESCC, suggesting that LD may be the site for eicosanoid production in EAC. In conclusion, this study shows that obesity, and BE- and EAC-associated inflammatory stimuli result in a gradual increase of LD, that may be responsible for orchestrating inflammatory mediators' production and/or action, thus contributing to BE and EAC genesis and progression.
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Adenocarcinoma/metabolismo , Esófago de Barrett/metabolismo , Ciclooxigenasa 2/metabolismo , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas de Esófago/metabolismo , Gotas Lipídicas/metabolismo , Transducción de Señal/fisiología , Adenocarcinoma/patología , Esófago de Barrett/patología , Línea Celular , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/patología , Esófago/metabolismo , Esófago/patología , Reflujo Gastroesofágico/metabolismo , Reflujo Gastroesofágico/patología , Humanos , Inflamación/metabolismo , Inflamación/patología , Factores de RiesgoRESUMEN
We study site- and bond-percolation on a class of lattices referred to as Lieb lattices. In two dimensions the Lieb lattice (LL) is also known as the decorated square lattice, or as the CuO_{2} lattice; in three dimensions it can be generalized to a layered Lieb lattice or to a perovskite lattice. Emergent electronic phenomena, such as topological states and ferrimagnetism, have been predicted to occur in these systems, which may be realized in optical lattices as well as in solid state. Since the study of the interplay between quantum fluctuations and disorder in these systems requires the availability of accurate estimates of geometrical critical parameters, such as percolation thresholds and correlation length exponents, here we use Monte Carlo simulations to obtain these data for LLs when a site (or bond) is present with probability p. We have found that the thresholds satisfy a mean-field (Bethe lattice) trend, namely that the critical concentration, p_{c}, increases as the average coordination number decreases; our estimates for the correlation length exponent are in line with the expectation that there is no change in the universality class.
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Lakes play a pivotal role in ecological and biogeochemical processes and have been described as "sentinels" of environmental change. Assessing "lake health" across large geographic scales is critical to predict the stability of their ecosystem services and their vulnerability to anthropogenic disturbances. The LakePulse research network is tasked with the assessment of lake health across gradients of land use on a continental scale. Bacterial communities are an integral and rapidly responding component of lake ecosystems, yet large-scale responses to anthropogenic activity remain elusive. Here, we assess the ecological impact of land use on bacterial communities from over 200 lakes covering more than 660,000 km2 across Eastern Canada. In addition to community variation between ecozones, land use across Eastern Canada also appeared to alter diversity, community composition, and network structure. Specifically, increasing anthropogenic impact within the watershed lowered diversity. Likewise, community composition was significantly correlated with agriculture and urban development within a watershed. Interaction networks showed decreasing complexity and fewer keystone taxa in impacted lakes. Moreover, we identified potential indicator taxa of high or low lake water quality. Together, these findings point to detectable bacterial community changes of largely unknown consequences induced by human activity within lake watersheds.
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Ecosistema , Lagos , Agricultura , Bacterias/genética , Canadá , HumanosRESUMEN
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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It is known that the level of dietary protein modulates the enzymatic activity of the digestive tract of fish; however, its effect at the molecular level on these enzymes and the hormones regulating appetite has not been well characterised. The objective of this study was to evaluate the effect of CP on the activity of proteases and the expression of genes related to the ingestion and protein digestion of juveniles of red tilapia (Oreochromis sp.), as well as the effects on performance, protein retention and body composition of tilapia. A total of 240 juveniles (29.32 ± 5.19 g) were used, distributed across 20 tanks of 100 l in a closed recirculation system. The fish were fed to apparent satiety for 42 days using four isoenergetic diets with different CP levels (24%, 30%, 36% and 42%). The results indicate that fish fed the 30% CP diet exhibited a higher growth performance compared to those on the 42% CP diet (P < 0.05). Feed intake in fish fed 24% and 30% CP diets was significantly higher than that in fish fed 36% and 42% CP diets (P < 0.05). A significant elevation of protein retention was observed in fish fed with 24% and 30% CP diets. Fish fed with 24% CP exhibited a significant increase in lipid deposition in the whole body. The diet with 42% CP was associated with the highest expression of pepsinogen and the lowest activity of acid protease (P < 0.05). The expression of hepatopancreatic trypsinogen increased as CP levels in the diet increased (P < 0.05) up to 36%, whereas trypsin activity showed a significant reduction with 42% CP (P < 0.05). The diet with 42% CP was associated with the lowest intestinal chymotrypsinogen expression and the lowest chymotrypsin activity (P < 0.05). α-amylase expression decreased with increasing (P < 0.05) CP levels up to 36%. No significant differences were observed in the expression of procarboxypeptidase, lipase or leptin among all the groups (P > 0.05). In addition, the diet with 42% CP resulted in a decrease (P < 0.05) in the expression of ghrelin and insulin and an increase (P < 0.05) in the expression of cholecystokinin and peptide yy. It is concluded that variation in dietary protein promoted changes in the metabolism of the red tilapia, which was reflected in proteolytic activity and expression of digestion and appetite-regulating genes.
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Cíclidos , Proteínas en la Dieta , Tilapia , Alimentación Animal/análisis , Animales , Cíclidos/genética , Dieta/veterinaria , Expresión Génica , Tilapia/metabolismoRESUMEN
A new species of Moniliformis Travassos, 1915 (Acanthocephala: Moniliformidae) is described from the hairy-tailed bolo mouse, Necromys lasiurus Lund, 1840 (Cricetidae: Sigmondontinae), captured in the Brazilian Cerrado, in Uberlândia, state of Minas Gerais, Brazil. The specimens were studied by light and scanning electron microscopy. Molecular phylogenies were inferred from partial nuclear large subunit ribosomal RNA gene sequences and partial mitochondrial cytochrome c oxidase subunit I gene. The new species is distinguished from other moniliformid species by the number of rows and number of hooks per row, size of the proboscis, size of the eggs, host species and geographical distribution. Molecular phylogenies and genetic distances analyses demonstrated that Moniliformis necromysi sp. n. forms a well-supported monophyletic group with sequences of other species of Moniliformis and is distinguished from them, which agrees with the morphological characteristics, allocating the new species to this genus and to the family Moniliformidae Van Cleave, 1924. This is the first moniliformid acanthocephalan described from a wild rodent in Brazil.
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Moniliformis/clasificación , Moniliformis/ultraestructura , Sigmodontinae/parasitología , Animales , Brasil , Femenino , Genes Mitocondriales/genética , Masculino , Microscopía Electrónica de Rastreo , Filogenia , ARN Ribosómico/genéticaRESUMEN
The lack of naturally occurring resistance to citrus psorosis virus (CPsV) necessitates a transgenic approach for the development of CPsV-resistant citrus. To evaluate the feasibility of conferring resistance to a non-transgenic scion, we have assembled citrus plants by grafting combining a non-transgenic Sweet Orange as scion, CPsV-resistant transgenic Sweet Orange lines expressing intron-hairpin (ihp) RNA derived from the viral coat protein (ihpCP) as interstock, and a non-transgenic citrus as rootstock. We demonstrated that ihpCP-transcripts translocate through the graft from interstock to scion, triggering the silencing of coat protein mRNA target. Two independent CPsV challenge assays showed that expression of ihpCP in the interstock provides resistance against CPsV in the interstock, and different levels of protection in the non-tg scion, depending of the virus delivery site. These results indicated that grafting is a promising biotechnological alternative to protect woody plants against virus infections in vegetative propagated plants.