RESUMEN
The biometric differences between fruits and seeds are useful characteristics that can provide important data for the investigation and preservation of the species and may be linked to environmental and genetic influences. In this sense, considering the importance of this species and the need for conservation, the objective was to carry out physical characterization of the fruits and seeds of Hymenaea martiana as well as to determine the seed imbibition curve. The experiment was conducted at the Seed Analysis Laboratory at the Agricultural Sciences Center at the Federal University of Paraíba in Areia, PB. The evaluations carried out were as follows: biometry of fruits and seeds, number of seeds per fruit, colorimetry of fruits and seeds, percentage of damaged seeds, weight of a thousand seeds, seed water content, mass and imbibition curve. The biometric data were subjected to descriptive analysis to determine the minimum, maximum, average value, standard deviation, asymmetry, and kurtosis of the fruits and seeds. In terms of the biometric characteristics of the fruits and seeds of H. martiana, there was a marked variation, with average fruit lengths of 90.28 mm, widths of 46.83 mm, thicknesses of 34.69 mm, weights of 65.86 g and four seeds per fruit. The average length, width, thickness and weight of the seeds were 23.75 mm, 18.34 mm, 12.71 g and 4.13 g, respectively. The fruits were darker than the seeds, and both the fruits and seeds had red tones. Compared with nonscarified seeds, scarified seeds absorb a greater amount of water.
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Biometría , Frutas , Hymenaea , Semillas , Semillas/anatomía & histología , Frutas/anatomía & histología , Hymenaea/anatomía & histología , Hymenaea/clasificación , Hymenaea/químicaRESUMEN
Variations in lipid profile have been observed in sickle cell disease (SCD) and understanding their relationship with disease severity is crucial. This study aimed to investigate the association of polymorphisms of the CETP gene and laboratory markers of disease severity with lipid profile in a pediatric population with SCD. Biochemical and anthropometric analyses and CETP and alpha-thalassemia genotyping were performed. The study included 133 children and adolescents with sickle cell anemia (SCA) or hemoglobin SC disease (SCC), in steady-state. The SCA and no hydroxyurea (no HU) groups had higher values of ApoB, total cholesterol, low-density lipoprotein cholesterol (LDL-C), and non-high-density lipoprotein cholesterol (non-HDL-C) compared to the SCC and HU groups. However, there were no significant differences in ApoA1 and HDL-C levels between the groups based on genotype. Furthermore, the groups with altered levels of ApoA1, HDL-C, and the triglyceride/HDL ratio exhibited lower hemoglobin (Hb) levels and higher white blood cell counts. Hb level was associated to HDL-C levels. Analysis of CETP gene variants showed that the minor alleles of rs3764261 (C>A), rs247616 (C>T), and rs183130 (C>T), as well as the TTA haplotype, are explanatory variables for HDL-C levels. These findings suggested that dyslipidemia in SCD, specifically related to HDL-C levels, may be influenced by individual genetic background. Additionally, further investigation is needed to determine if clinical manifestations are impacted by CETP gene variants.
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Anemia de Células Falciformes , Niño , Adolescente , Humanos , Haplotipos , HDL-Colesterol , Genotipo , Alelos , Proteínas de Transferencia de Ésteres de ColesterolRESUMEN
Variations in lipid profile have been observed in sickle cell disease (SCD) and understanding their relationship with disease severity is crucial. This study aimed to investigate the association of polymorphisms of the CETP gene and laboratory markers of disease severity with lipid profile in a pediatric population with SCD. Biochemical and anthropometric analyses and CETP and alpha-thalassemia genotyping were performed. The study included 133 children and adolescents with sickle cell anemia (SCA) or hemoglobin SC disease (SCC), in steady-state. The SCA and no hydroxyurea (no HU) groups had higher values of ApoB, total cholesterol, low-density lipoprotein cholesterol (LDL-C), and non-high-density lipoprotein cholesterol (non-HDL-C) compared to the SCC and HU groups. However, there were no significant differences in ApoA1 and HDL-C levels between the groups based on genotype. Furthermore, the groups with altered levels of ApoA1, HDL-C, and the triglyceride/HDL ratio exhibited lower hemoglobin (Hb) levels and higher white blood cell counts. Hb level was associated to HDL-C levels. Analysis of CETP gene variants showed that the minor alleles of rs3764261 (C>A), rs247616 (C>T), and rs183130 (C>T), as well as the TTA haplotype, are explanatory variables for HDL-C levels. These findings suggested that dyslipidemia in SCD, specifically related to HDL-C levels, may be influenced by individual genetic background. Additionally, further investigation is needed to determine if clinical manifestations are impacted by CETP gene variants.
RESUMEN
The kinetics of an ion channel are classically understood as a random process. However, studies have shown that in complex ion channels, formed by multiple subunits, this process can be deterministic, presenting long-term memory. Staphylococcus aureus α-hemolysin (α-HL) is a toxin that acts as the major factor in Staphylococcus aureus virulence. α-HL is a water-soluble protein capable of forming ion channels into lipid bilayers, by insertion of an amphipathic ß-barrel. Here, the α-HL was used as an experimental model to study memory in ion channel kinetics. We applied the approximate entropy (ApEn) approach to analyze randomness and the Detrended Fluctuation Analysis (DFA) to investigate the existence of long memory in α-HL channel kinetics. Single-channel currents were measured through experiments with α-HL channels incorporated in planar lipid bilayers. All experiments were carried out under the following conditions: 1 M NaCl solution, pH 4.5; transmembrane potential of + 40 mV and temperature 25 ± 1 °C. Single-channel currents were recorded in real-time in the memory of a microcomputer coupled to an A/D converter and a patch-clamp amplifier. The conductance value of the α-HL channels was 0.82 ± 0.0025 nS (n = 128). The DFA analysis showed that the kinetics of α-HL channels presents long-term memory ([Formula: see text] = 0.63 ± 0.04). The ApEn outcomes showed low complexity to dwell times when open (ApEno = 0.5514 ± 0.28) and closed (ApEnc = 0.1145 ± 0.08), corroborating the results of the DFA method.
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Proteínas Hemolisinas , Canales Iónicos , Membrana Dobles de Lípidos , Proteínas Hemolisinas/metabolismo , Canales Iónicos/metabolismo , Cinética , Staphylococcus aureusRESUMEN
Immune reconstitution after hematopoietic stem cell transplantation (HSCT) is a complex and extremely variable process. The Ikaros transcription factor plays an important role in hematopoiesis in several cell lines, especially in the lymphoid lineage. We hypothesized that Ikaros might influence immune reconstitution, and consequently, the risk of opportunistic infections, relapse, and graft versus host disease (GVHD). Samples were collected from the graft and from the peripheral blood (PB) of the recipients 3 weeks after neutrophil recovery. Real-time polymerase chain reaction (RT-PCR) was performed to analyze the absolute and relative Ikaros expression. Patients were divided into two groups, according to Ikaros expression in the graft and in the recipients' PB based on the ROC curves for moderate/severe cGVHD. A cutoff of 1.48 was used for Ikaros expression in the graft, and a cutoff of 0.79 was used for Ikaros expression in the recipients' PB. Sixty-six patients were included in this study. Median age of patients was 52 years (range 16-80 years), 55% of them were male, and 58% of them had acute leukemia. Median follow-up period was 18 months (range 10-43 months). There was no association between Ikaros expression and the risk of acute GVHD, relapse, or mortality. However, a significant association was observed with the risk of chronic GVHD. Higher Ikaros expression in the graft was associated with a significantly higher cumulative incidence (CI) of moderate/severe chronic GVHD according to the National Institute of Health (NIH) classification at two years (54% vs. 15% for patients with lower expression, P = 0.03). A higher Ikaros expression in the recipients' PB 3 weeks after engraftment was also associated with a significantly higher risk of moderate/severe chronic GVHD (65% vs. 11%, respectively, P = 0.005). In conclusion, Ikaros expression in the graft and in the recipients' PB after transplantation was associated with a higher risk of moderate/severe chronic GVHD. Ikaros expression should be evaluated in larger prospective trials as a potential biomarker for chronic GVHD.
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Síndrome de Bronquiolitis Obliterante , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Factor de Transcripción Ikaros , Leucemia Mieloide Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Enfermedad Crónica , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Leucemia Mieloide Aguda/etiología , Estudios Prospectivos , Recurrencia , Factor de Transcripción Ikaros/genética , Factor de Transcripción Ikaros/metabolismoRESUMEN
Polyploidy and whole genome duplication are major evolutionary drivers in plants. Climate variations during the Pleistocene have influenced distribution and range expansion worldwide. Similar trends have been reported for Cerrado plants, but no attempt has been made to link phylogeography with ploidy and breeding changes. Thus, we aimed to (i) assess ploidy and genome size of Eriotheca estevesiae Carv.-Sobr., and compare it with E. pubescens (Mart.) Schott & Endl. (Both included into the Eriotheca Stellate Trichome Species Complex - ESTSC). (ii) Subsequently, we investigated their phylogeography to see whether genetic structure and range expansion trends were similar to those previously described for the Cerrado biome. Finally (iii), we discuss whether ESTSC phylogeographic patterns could be associated with geographic parthenogenesis processes. Common cytogenetic techniques and flow cytometry were used to confirm chromosome number and genome size of E. estevesiae. We used three cpDNA regions to analyse 14 ESTSC Cerrado populations, for which we also obtained ploidy level and breeding information. We investigated haplotype diversity, population structure and tested neutrality, aiming to reconstruct phylogeographic scenarios. We found three ploidy levels and eight cpDNA haplotypes in ESTSC, one shared by most populations. Haplotype and ploidy distribution corroborated that E. pubescens, the widely distributed polyploid and apomictic species, may have originated from northern diploid and probably sexual E. estevesiae. Matrilinear cpDNA links support the idea that apomixis and polyploidy in ESTSC may have allowed range expansion during the Pleistocene, in a process analogous to the geographic parthenogenesis described elsewhere.
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Apomixis , Filogeografía , Árboles/genética , Pradera , Semillas , Fitomejoramiento , Poliploidía , ADN de Cloroplastos/genética , Variación GenéticaRESUMEN
PURPOSE: This study investigated the microshear bond strength between a resin cement and a translucent zirconia subjected to multiple characterization firings. METHODS AND MATERIALS: 5Y-PSZ zirconia blocks (Katana UTML) were sliced, sintered (1550°C, 2 h), and randomly divided into six groups (n=10) according to the number of characterization firings (0, 1, 2, 3, 5, or 10) and aging (baseline or after thermocycling). Each characterization firing was performed at 750°C for 1 minute. The ceramic surfaces were all sandblasted with 50 µm Al2O3 and silanized. Then, cylinders of resin cement (0.96 mm diameter × 2 mm height) were bonded onto their surfaces. The baseline samples were immersed in distilled water for 24 hours before the microshear bond strength (µSBS) tests. The aged samples were tested after 5000 thermocycles in water (5°C-55°C). The failure modes were classified as adhesive, predominantly adhesive, or cohesive. Scanning electron microscope images of the failure modes and the ceramic surfaces after the firings were taken. The µSBS data were analyzed by two-way ANOVA and Tukey's test. RESULTS: The number of characterization firings and aging affected the bond strength. The highest bond strength values were observed from the 2-firing group at baseline. The µSBS results after 1, 2, or 3 characterization firings were similar at baseline and after aging. On the other hand, 0, 5, and 10 firings revealed the lowest bond strengths. The most frequent failures were adhesive and predominantly adhesive. Zirconia grains were not affected by the multiple firings. CONCLUSION: One to three characterization firings after sintering improve the bond strength of 5Y-PSZ to the resin cement when compared to none or several (five or ten) firing cycles.
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Recubrimiento Dental Adhesivo , Cementos de Resina , Circonio , Cerámica/química , Recubrimiento Dental Adhesivo/métodos , Análisis del Estrés Dental , Ensayo de Materiales , Cementos de Resina/química , Resistencia al Corte , Propiedades de Superficie , Agua/química , Circonio/químicaRESUMEN
INTRODUCTION AND HYPOTHESIS: The objectives were to evaluate clinical and anatomical parameters assessed by three-dimensional pelvic floor ultrasound (3D ultrasound) in parous and nulliparous women of childbearing age and to assess underreported symptoms of sexual dysfunction (SD), urinary incontinence (UI) and flatus incontinence (FI). METHODS: Women without complaints of pelvic floor dysfunction, aged 20-50 years, were eligible for this prospective cross-sectional study. They completed the King's Health Questionnaire, Female Sexual Function Index and St Mark's Incontinence Score adapted for this study. Next, a physical examination and 3D ultrasound were performed. The scores obtained in the questionnaires were compared with the 3D ultrasound data. RESULTS: In total, 326 women were invited to participate. Of these, 203 women met the inclusion criteria, and their cases were classified as nulliparity (NU, 59), vaginal delivery (VD, 80), forceps delivery (FD, 18) and caesarean section (CS, 48). These groups were homogeneous regarding age (p=0.096), parity (p=0.051) and body mass index (p=0.06). The hiatal dimension (HD; p=0.003) and transverse diameter (TD) (p=0.001) were significantly different among the groups. Compared with the NU and CS groups, the VD and FD groups had an increased HD and TD. The frequencies of underreported symptoms identified by questionnaires were as follows: SD (46.3%), UI (35%) and FI (28%). After VD and FD, women were more likely to present UI (p<0.001), FI (p<0.001) and SD (p=0.002) than the women with NU and those who had undergone a CS. UI was related to a greater HD (p=0.002) and anteroposterior diameter (p=0.022), FI was associated with a thinner left pubovisceral muscle (p=0.013), and SD was related to a greater HD (p=0.026). CONCLUSIONS: Three-dimensional ultrasound can identify mild morphological changes in young women with apparently normal physical examinations, mainly after VD and FD. In such individuals, these findings are associated with higher incidences of underreported sexual, urinary and anal symptoms.
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Incontinencia Fecal , Disfunciones Sexuales Fisiológicas , Incontinencia Urinaria , Femenino , Embarazo , Humanos , Paridad , Cesárea/efectos adversos , Diafragma Pélvico/diagnóstico por imagen , Estudios Transversales , Estudios Prospectivos , Incontinencia Fecal/etiología , Incontinencia Urinaria/diagnóstico por imagen , Incontinencia Urinaria/etiología , Incontinencia Urinaria/epidemiología , Parto Obstétrico/métodosRESUMEN
Partial or complete bladder eversion is a rare condition of poor prognosis in cows, commonly associated with intense tenesmus observed in the peripartum period. A 14-year-old obese Nellore cow at 280 days of gestation was referred with 24-hour bladder prolapse. The bladder was complete eversion through the vulvar vestibule showing a thick congested wall and small residual urine volume. After clinical examination, the cow received scopolamine butylbromide and intercoccygeal epidural anesthesia, and the externalized bladder segment was partially reduced, remaining only 10 cm externalized. The cow was maintained with an intravesical human gastric tube number 16 and constant monitoring. The eversion was fully reduced after 12 hours of local treatment, and as the cow presented subclinical ketosis, hypocalcemia and cystitis, antibiotic, glucose, calcium and propylene glycol therapy were performed. We opted for induction of parturition, and after 24 hours, a healthy 52kg calf was born and the placenta was delivered 16 hours after calving. The cow and calf were discharged on the sixth day of hospitalization, with no recurrences or secondary complications after treatment.
A eversão vesical parcial ou completa é uma condição rara de mau prognóstico em vacas, comumente associada a tenesmo intenso observado no período periparto. Uma vaca Nelore obesa de 14 anos de idade, com 280 dias de gestação, foi encaminhada com prolapso de bexiga de 24 horas. A bexiga apresentava eversão completa por meio do vestíbulo vulvar apresentando parede espessa e congestionada e pequeno volume residual de urina. Após exame clínico, a vaca recebeu butilbrometo de escopolamina e anestesia peridural intercoccígea, e o segmento vesical exteriorizado foi parcialmente reduzido, permanecendo apenas 10cm exteriorizado. A vaca foi mantida com sonda gástrica humana número 16 por via intravesical e monitorada constantemente. A eversão foi totalmente reduzida após 12 horas de tratamento local, e, como a vaca apresentava cetose subclínica, hipocalcemia e cistite, foi realizada antibioticoterapia, glicose, cálcio e propilenoglicol. Optou-se pela indução do parto. Após 24 horas, nasceu um bezerro saudável de 52kg e a placenta foi expelida 16 horas após o parto. A vaca e o bezerro receberam alta no sexto dia de internação, sem recidivas ou complicações secundárias após o tratamento.
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Animales , Bovinos , Vejiga Urinaria/anomalías , Enfermedades de los Bovinos , Cistitis/veterinaria , Complicaciones del Trabajo de Parto/veterinariaAsunto(s)
Miembro Anterior , Lidocaína , Caballos , Animales , Administración Intravenosa/veterinaria , Perfusión/veterinariaRESUMEN
Chronic Progressive Lymphoedema (CPL) is a disabling disease of draft horses that affects lymphatic system function typically in the distal limbs. Deformities of distal limbs, especially of the pastern, with fibrosis and skin nodular lesions are consequences of disease progression. A 15-year-old Friesian stallion presented for evaluation with history of forelimb enlargement and nodule formations distal to the carpus for four years. Simple radiographs showed soft tissue nodular lesions and venous contrasted radiography showed intense enlargement of II common digital palmar vein of both forelimbs. Tissue culture tests revealed Streptococcus equi and Proteus mirabilis isolation and skin scraping test identified Chorioptes bovis mites. Histological examination revealed perivasculitis and lymph vessels distention. History, clinical and histological findings, and complementary exams suggested CPL diagnosis. We were unable to find previously published cases describing this disease in Brazil, where the increasing number of draft horses requires attention to this problem. The correct and early diagnosis substantially delays disease progression. Therefore, we highlight the need for nationwide propagation of these data to ensure better diagnosis and early treatment of future CPL cases.
O linfedema crônico progressivo (LCP) é uma enfermidade incapacitante de cavalos de tração que afeta o sistema linfático e se manifesta especialmente na região distal dos membros. A progressão da doença resulta em deformações na região distal dos membros, especialmente na quartela, com fibrose e lesões nodulares na pele. Foi atendido um garanhão da raça Friesian, de 15 anos de idade, com histórico de aumento de volume, nodulações e deformações na região distal dos membros torácicos, com início há aproximadamente quatro anos. Ao exame radiográfico simples, foram identificadas nodulações na pele e no subcutâneo e, ao exame venoso contrastado, identificou-se marcante dilatação II veia digital palmar comum em ambos os membros torácicos. Foi isolado Streptococcus equi e Proteus mirabilis ao cultivo tecidual e identificou-se sarna do tipo corióptica ao raspado de pele. No exame histopatológico, foram identificadas perivasculite e dilatação de vasos linfáticos. Os achados clínicos, histórico, de raça do animal e os exames complementares direcionaram o diagnóstico para o LCP. A pesquisa da literatura nacional não revelou descrições clínicas dessa enfermidade, mas, devido ao aumento do número de animais de tração no país nos últimos anos, a descrição dessa enfermidade se torna importante. O diagnóstico correto e precoce é necessário para retardar a progressão da doença. Nesse sentido, ressalta-se a relevância da divulgação nacional desses achados, a fim de contribuir para o diagnóstico precoce e permitir o retardo da evolução da doença.
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Animales , Dermatitis , Miembro Anterior , Caballos , Sistema Linfático , LinfedemaRESUMEN
BACKGROUND: Coronary arterial dominance and myocardial bridges have clinical implications, since a left dominant pattern associated to the presence of myocardial bridges is often associated to a higher incidence of arteriosclerosis and higher mortality by myocardial infarction. OBJECTIVE: To determine the presence and position of myocardial bridges and their relation with coronary arterial dominance. METHODS: Fifty-seven human cadaveric hearts were analyzed into three groups, as follows: right dominance; left dominance; codominance. Each group was then divided into two subgroups: with or without myocardial bridges. Finally, each subgroup with myocardial bridges was classified according to the position of the myocardial bridge according to the main axis of the heart (proximal, middle and distal third). RESULTS: The right dominance occurred in most hearts (30 hearts-52,6%). Twenty-three myocardial bridges (40,3%) were identified and mostly occurred on left dominant hearts (22,8%). The pattern of coronary dominance presented a statistically significant correlation with the presence of myocardial bridges (P=0.048). The middle third of the heart axis showed the highest occurrence of myocardial bridges. CONCLUSION: These findings suggest there is a clear relationship between the presence of myocardial bridges and left dominant pattern. Middle third of the heart axis present the higher occurrence of myocardial bridges. Knowledge of the myocardial bridges morphology is of great clinical significance, improving patient care.
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Vasos Coronarios , Miocardio , Brasil/epidemiología , Vasos Coronarios/anatomía & histología , Humanos , IncidenciaRESUMEN
HIV-1 infection is a global epidemic whose treatment is limited majorly by viral resistance and adverse effects. Natural products from algae have been studied for many years, including antiviral, being an alternative to anti-HIV drug design. Since the isolation of natural products can be a hurdle, molecular modeling is an important tool to study these compounds. Herein, structure-activity relationship, molecular docking, and molecular dynamic studies were performed to direct the studies of ten marine natural products with anti-HIV activity. In the structure-activity relationship, descriptors were identified associating the anti-HIV activity of five diterpenes with possible action on the reverse transcriptase allosteric site. These diterpenes were evaluated by molecular docking, and it was identified that only dolabelladienetriol interacted in the allosteric site. Molecular dynamics suggested that the dolabelladienetriol might interfere with the viral RNA binding to HIV-1 RT by inducing a conformational change of the enzyme. Also, in silico ADMET simulations predicts that the dolabelladienetriol present a high potential to be successfully developed as a drug. Thus, applying in silico approaches was possible to suggest potential anti-HIV compounds derived from marine natural products.Communicated by Ramaswamy H. Sarma.
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Fármacos Anti-VIH , Productos Biológicos , Diterpenos , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , Productos Biológicos/farmacología , Diterpenos/farmacología , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Relación Estructura-Actividad Cuantitativa , Relación Estructura-ActividadAsunto(s)
Antibióticos Antituberculosos , Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Antibióticos Antituberculosos/farmacología , Antibióticos Antituberculosos/uso terapéutico , Farmacorresistencia Bacteriana , Humanos , Rifampin/farmacología , Sensibilidad y Especificidad , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológicoRESUMEN
BACKGROUND: Studies show that healthcare-associated infections (HAIs) represent a crucial issue in healthcare and can lead to substantial economic impacts in intensive care units (ICUs). AIM: To estimate direct costs associated with the most significant HAIs in 50 teaching hospitals in Brazil, affiliated to the unified health system (Sistema Único de Saúde: SUS). METHODS: A Monte Carlo simulation model was designed to estimate the direct costs of HAIs; first, epidemiologic and economic parameters were established for each HAI based on a cohort of 949 critical patients (800 without HAI and 149 with); second, simulation based on three Brazilian prevalence scenarios of HAIs in ICU patients (29.1%, 51.2%, and 61.6%) was used; and third, the annual direct costs of HAIs in 50 university hospitals were simulated. FINDINGS: Patients with HAIs had 16 additional days in the ICU, along with an extra direct cost of US$13.892, compared to those without HAIs. In one hypothetical scenario without HAI, the direct annual cost of hospital care for 26,649 inpatients in adult ICUs of 50 hospitals was US$112,924,421. There was an increase of approximately US$56 million in a scenario with 29.1%, and an increase of US$147 million in a scenario with 61.6%. The impact on the direct cost became significant starting at a 10% prevalence of HAIs, where US$2,824,817 is added for each 1% increase in prevalence. CONCLUSION: This analysis provides robust and updated estimates showing that HAI places a significant financial burden on the Brazilian healthcare system and contributes to a longer stay for inpatients.
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Infección Hospitalaria , Adulto , Brasil/epidemiología , Infección Hospitalaria/epidemiología , Atención a la Salud , Hospitales Universitarios , Humanos , Unidades de Cuidados Intensivos , Tiempo de InternaciónRESUMEN
Ion channels are transport proteins present in the lipid bilayers of biological membranes. They are involved in many physiological processes, such as the generation of nerve impulses, hormonal secretion, and heartbeat. Conformational changes in the ion channel-forming protein allow the opening or closing of pores to control the ionic flux through the cell membranes. The opening and closing of the ion channel have been classically treated as a random kinetic process, known as a Markov process. Here the time the channel remains in a given state is assumed to be independent of the condition it had in the previous state. More recently, however, several studies have shown that this process is not random but a deterministic one, where both the open and closed dwell-times and the ionic current flowing through the channel are history-dependent. This property is called long memory or long-range correlation. However, there is still much controversy regarding how this memory originates, which region of the channel is responsible for this property, and which models could best reproduce the memory effect. In this article, we provide a review of what is, where it is, its possible origin, and the mathematical methods used to analyze the long-term memory present in the kinetic process of ion channels.
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Canales Iónicos , Modelos Biológicos , Canales Iónicos/metabolismo , Cinética , Cadenas de MarkovRESUMEN
SUMMARY: The objective of this study was to determine the occurrence of anatomical variants in the exocranial surface of the jugular foramen, specifically, the presence of single or double and complete or incomplete septation. A cross-sectional anatomical study was performed using 96 Brazilian dry human skulls (53 male and 43 female). One examiner determined the number (single or double) and type (i.e. complete or incomplete) of osseous septation at the outer surface of jugular foramens. Data went through statistical analysis on GraphPad Prism 6.01. Our results shown that Male individuals where more likely to present normal jugular foramens (male = 71.69%, female = 34.88%; p = 0.003). However, one incomplete septation occurred more often on the right side of female individuals (1 incomplete septation, male = 16.98%; 1 incomplete septation, female = 34.88%; p = 0.044). Similarly, one complete septation (i.e. the presence of two fully divided jugular compartments) also occurred more often on the right side of female individuals (1 complete septation, male = 9.43%; 1 complete septation, female = 25.58%; p = 0.038). Anatomical variants of the jugular foramen regarding single or double complete or incomplete septations were more likely to be found on the right side of female individuals, whose also presented a higher rate of jugular foramens with any type of septation than regular non-altered jugular foramens.
RESUMEN: El objetivo de la presente investigación fue determinar la presencia de variaciones anatómicas en la superficie exocraneal del foramen yugular, especificamente, la presencia de septos únicos o dobles, completos o incompletos. El estudio fue realizado en 96 cráneos secos (53 masculinos y 43 femeninos) de indivíduos Brasileños. Se determinaron septos óseos completos o incompletos y número de ellos. Los resultados obtenidos fueron tratados estadísticamente con el programa GraphPad Prism 6.01. Los sujetos de sexo masculino fueron más propensos a presentar forámenes yugulares normales (sexo masculino: 71,69%; sexo femenino: 34,88%, p= 0,003). Sin embargo, se observaron septos incompletos con mayor frecuencia en el lado derecho y en el sexo femenino (sexo masculino: 16,98%; sexo femenino: 34,88%, p=0,044). Adicionalmente, una septación completa (presencia de dos compartimientos yugulares, divididos completamente), se presentaron más frecuentemente en el lado derecho de indivíduos femeninos (sexo masculino: 9,43%; sexo femenino: 25,58%, p= 0,038). Las variantes anatómicas del foramen yugular, en relación a septos simples o dobles, completos o incompletos, se encontraron con mayor frecuencia en el lado derecho de las mujeres, las que presentaron un alto rango de forámenes yugulares con algún tipo de septos respecto a los forámenes yugulares regulares no alterados.
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Humanos , Masculino , Femenino , Foramina Yugular/anatomía & histología , Estudios Transversales , Variación AnatómicaRESUMEN
Geographic parthenogenesis, range expansion of apomictic plants after climate changes, has been described for Northern Hemisphere gametophytic apomicts. But similar trends have been observed for sporophytic apomicts of Cerrado, the savannas in Brazil. Eriotheca pubescens is a common Cerrado tree, an agamic complex of either hexaploid/polyembryonic apomicts or tetraploid/monoembryonic sexual individuals. Some populations have been described as a new species, Eriotheca estevesiae, all included in the Eriotheca Stellate Trichome Species Complex (ESTSC). Since breeding systems and ploidy are clearly associated with polyembryony and stomatal size, we used these ancillary features to map the reproductive and ploidy level traits of E. pubescens and E. estevesiae. Leaves and seeds were collected from individuals of 19 populations. Seeds were evaluated for the presence of polyembryony and leaves for stomatal measurements. Eight populations were monoembryonic while another eight were polyembryonic and for other three, the embryonic pattern was not readily verified. E. pubescens polyembryonic and hexaploid populations formed a homogeneous group, but monoembryonic plants were more variable. E. estevesiae populations were monoembryonic with smaller stomata. In contrast, some E. pubescens monoembryonic populations further south presented larger stomata. Despite these outliers, possibly mixed populations, stomatal size and embryonic pattern differed from northern to southern populations. Embryonic pattern and stomatal size indicated that northernmost populations of Eriotheca STSC (E. estevesiae) are diploid and sexual. Southernmost populations, mostly polyembryonic and with large stomata, are hexaploid and apomictic. This is in agreement with geographic parthenogenesis and range expansion of apomictic lineages to southern habitats available after the last glacial maximum.
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Malvaceae/anatomía & histología , Malvaceae/genética , Estomas de Plantas/anatomía & histología , Ploidias , Brasil , Malvaceae/clasificación , Fitomejoramiento , SemillasRESUMEN
AIMS: To investigate the effects of the lectin from Punica granatum sarcotesta (PgTeL) on growth, viability, cell structure, biofilm formation and chitinase activity of Listeria monocytogenes. In addition, the effect of PgTeL on the adhesion and invasion of human cells (HeLa) was determined. METHODS AND RESULTS: PgTeL showed bacteriostatic and bactericidal effects on the strains L. monocytogenes N53-1 and EGD-e, causing morphometric alterations, cell aggregation, strong deformation and cell disruption. PgTeL inhibited biofilm formation by EGD-e and N53-1 and also interfered with the adhesion and invasion processes of EGD-e and N53-1 in HeLa cells. Finally, the chitinase activity of L. monocytogenes EGD-e was reduced in the presence of PgTeL, which can be involved in the inhibition of adhesion process. CONCLUSION: PgTeL is an antibacterial agent against L. monocytogenes, inhibiting growth and promoting cell death, as well as impairing biofilm formation and bacterial adhesion and invasion into human cells. SIGNIFICANCE AND IMPACT OF THE STUDY: The results stimulate future investigations on the potential of PgTeL for protection of contamination in food products.
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Antibacterianos/farmacología , Lectinas/farmacología , Listeria monocytogenes/efectos de los fármacos , Granada (Fruta) , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Células HeLa , Humanos , Listeria monocytogenes/fisiologíaRESUMEN
SUMMARY: The aim of the present study was to determine the accuracy, sensitivity, and specificity of the clinical and radiographic examination (CRE) method compared to the examination with the dental operating microscope (DOM) on the detection of anatomical features of mesiobuccal canals in maxillary first molars. One hundred maxillary first molars were selected to assess the number of canals orifice entrances, accessibility, and ending of their mesiobuccal canals using the CRE method and the examination with the DOM. The diagnostic tests of the CRE exhibited, in general, high levels of accuracy, sensitivity, and specificity. However, low levels of these outcomes occurred, mainly, on the detection of the number of canals entrance orifices of the mesiobuccal root. The statistically significant differences (p<0.05) occurred for accessibility and ending of canals in 61 of the 62 cases (out of 100) when two of them were present: 2 accessible root canals (48 cases; 77.42 %), and 1 accessible and 1 inaccessible canals (13 cases; 20.97 %); 1 foramen after fusion (18 cases; 29.03 %), 2 foramens (30 cases; 48.39 %), and 1 foramen and 1 blind foramen (13 cases; 20.97 %). This study proves that the clinical and radiographic method (still the most commonly used worldwide) can't be trusted absolutely in situations of complex internal anatomy regarding the mesiobuccal root canals of maxillary first molars.
RESUMEN: El objetivo del presente estudio fue determinar la precisión, sensibilidad y especificidad del método de examen clínico y radiográfico (ECR) en comparación al examen con el microscopio quirúrgico dental (MQD) en la detección de características anatómicas de los canales mesiovestibulares en primeros molares maxilares.Se seleccionaron 100 primeros molares maxilares para evaluar el número de entradas de los canales, la accesibilidad y la terminación de sus canales mesiovestibulares utilizando el método ECR y el examen con el MQD.Las pruebas de diagnóstico del ECR exhibieron, en general, altos niveles de precisión, sensibilidad y especificidad. Sin embargo, también hubo niveles bajos de estos resultados, principalmente, en la detección del número de orificios de entrada a los canales de las raíces mesiovestibulares. Hubo diferencias estadísticamente significativas (p<0,05) para la accesibilidad y terminación de los canales en 61 de los 62 casos (del total de 100), cuando dos de ellos estaban presentes: 2 canales radiculares accesibles (48 casos, 77,42 %), y 1 accesible y 1 inaccesible (13 casos, 20,97 %). Después de la fusión, un orificio (18 casos, 29,03 %), 2 orificios (30 casos, 48,39 %) y 1 orificio más otro, ciego (13 casos, 20,97 %). Este estudio demuestra que no se puede confiar plenamente en el método clínico y radiográfico (todavía el más utilizado en todo el mundo), cuando existe una anatomía interna compleja de los canales de la raíz mesiovestibular de los primeros molares superiores.