RESUMEN
Nitrate-reducing oral bacteria have gained a lot of interest due to their involvement in nitric oxide (NO) synthesis and its important cardiometabolic outcomes. Consortia of nitrate-metabolizing oral bacteria associated with cardiometabolic health and cognitive function have been recently identified. Longitudinal studies and clinical trials have shown that chronic mouthwash use is associated with increased blood pressure and increased risk for prediabetes/diabetes and hypertension. Concurrently, recent studies are beginning to shed some light on the complexity of nitrate reduction pathways of oral bacteria, such as dissimilatory nitrate reduction to ammonium (DNRA), which converts nitrite into ammonium, and denitrification, which converts nitrite to NO, nitrous oxide, and dinitrogen. These pathways can affect the composition and metabolism of the oral microbiome; consequently, salivary nitrate and nitrite metabolism have been proposed as targets for probiotics and oral health. These pathways could also affect systemic NO levels because NO generated through denitrification can be oxidized back to nitrite in the saliva, thus facilitating flux along the NO3--NO2--NO pathway, while DNRA converts nitrite to ammonium, leading to reduced NO. It is, therefore, important to understand which pathway predominates under different oral environmental conditions, since the clinical consequences could be different for oral and systemic health. Recent studies show that oral hygiene measures such as tongue cleaning and dietary nitrate are likely to favor denitrifying bacteria such as Neisseria, which are linked with better cardiometabolic health. A vast body of literature demonstrates that redox potential, carbon-to-nitrate ratio, and nitrate-to-nitrite ratio are key environmental drivers of the competing denitrification and DNRA pathways in various natural and artificial ecosystems. Based on this information, a novel behavioral and microbial model for nitric oxide metabolism and health is proposed, which links lifestyle factors with oral and systemic health through NO metabolism.
Asunto(s)
Compuestos de Amonio , Enfermedades Cardiovasculares , Microbiota , Bacterias/metabolismo , Humanos , Nitratos/metabolismo , Óxido Nítrico/metabolismo , Nitritos/metabolismoRESUMEN
BACKGROUND/OBJECTIVES: Dual-energy X-ray absorptiometry (DXA) is considered a specific method for measuring body composition to assess obesity and osteoporosis, although few studies have been conducted in preschool children. The aim of this study was to provide sex - and age-specific references for bone mineral density (BMD), bone mineral content (BMC), fat mass (FM) and fat-free mass (FFM) normative data for children aged 2 to <6 years. SUBJECTS/METHODS: One hundred and eighty seven healthy white children from Buenos Aires City suburbs, Argentina, were studied by the Lunar DPX-L DXA, pediatric software: BMC less head (g), BMD (g/cm2), FM (%) and FFM (g). RESULTS: BMD and BMC increased significantly with age (P<0.0001), but only BMD was significantly different between boys and girls of similar age, being greater for boys (P=0.013). FM was not significantly different among the various age groups of boys and girls. However, the FFM/height was higher in boys and the BMC/FFM was higher in girls. The Z-scores and centile curves were derived separately for each sex and age. Q-Q detrended plots and LMS curves produced robust, unbiased fits that generated references for the 3rd, 50th and 97th percentiles for BMD, BMC, FM and FFM data, respectively. CONCLUSIONS: These DXA scans add to the scarcity of accurate measurements of body composition of white young children. The data analyses provided greater accuracy, particularly at the upper and lower ends of the distribution, which is important in clinical settings for identification of children with impaired body composition.
Asunto(s)
Composición Corporal , Obesidad Infantil/fisiopatología , Absorciometría de Fotón , Tejido Adiposo , Distribución por Edad , Argentina , Densidad Ósea , Huesos , Niño , Preescolar , Femenino , Humanos , Masculino , Valores de Referencia , Distribución por Sexo , Población BlancaRESUMEN
UNLABELLED: Bacterial urease activity in dental plaque and in saliva generates ammonia, which can increase the plaque pH and can protect acid-sensitive oral bacteria. Recent cross-sectional studies suggest that reduced ability to generate ammonia from urea in dental plaque can be an important caries risk factor. In spite of this proposed important clinical role, there is currently no information available regarding important clinical aspects of oral ureolysis in children. OBJECTIVE: The objective of this study was to evaluate the distribution and pattern of urease activity in the dental plaque and in the saliva of children during a three-year period, and to examine the relationship of urease with some important caries risk factors. METHODS: A longitudinal study was conducted with repeated measures over a three-year period on a panel of 80 children, aged 3-6 years at recruitment. The dynamics of change in urease activity were described and associated with clinical, biological, and behavioural caries risk factors. RESULTS: Urease activity in plaque showed a trend to remain stable during the study period and was negatively associated with sugar consumption (P<0.05). Urease activity in unstimulated saliva increased with age, and it was positively associated with the levels of mutans streptococci in saliva and with the educational level of the parents (P<0.05). CONCLUSIONS: The results of this study reveal interesting and complex interactions between oral urease activity and some important caries risk factors. Urease activity in saliva could be an indicator of mutans infection in children.
Asunto(s)
Placa Dental/enzimología , Saliva/enzimología , Saliva/microbiología , Streptococcus mutans/enzimología , Ureasa/metabolismo , Biopelículas , Niño , Preescolar , Índice CPO , Caries Dental/etiología , Sacarosa en la Dieta , Escolaridad , Femenino , Humanos , Concentración de Iones de Hidrógeno , Funciones de Verosimilitud , Modelos Lineales , Masculino , Padres , Estudios Prospectivos , Factores de Riesgo , Estadísticas no ParamétricasRESUMEN
OBJECTIVE: Dietary sugar exposures induce an immediate drop of the plaque pH. Based on in vitro observations, it was hypothesized that oral bacteria may rapidly respond to this environmental change by increasing the activity or expression of alkali-generating pathways, such as the urease pathway. The objective of this exploratory in vivo study was to determine the short-term effect of a brief sucrose exposure on plaque and saliva urease activity and expression, and to relate this effect to caries experience. METHODS: Urease activity levels were measured in plaque and saliva samples collected from 20 children during fasting conditions and 30 min after rinsing with a sucrose solution. Streptococcus salivarius ureC-specific mRNA in saliva was quantified using real-time RT-PCR. The impact of host-related factors, such as age, gender, sugar consumption, salivary mutans streptococci levels and caries status on urease activity was evaluated. RESULTS: Plaque urease activity under fasting conditions was higher in subjects with low caries and mutans streptococci levels. This difference was not observed after the sucrose exposure. The response of urease to sucrose in vivo did not depend on caries experience or salivary mutans levels. Significant increase in urease activity of plaque and saliva after exposure to sucrose was observed only in the subjects who had low urease levels at baseline. CONCLUSIONS: The findings of this exploratory study suggest that plaque urease activity may have an important long-term influence in caries development but not during a cariogenic challenge.
Asunto(s)
Placa Dental/enzimología , Sacarosa en la Dieta/farmacología , Saliva/enzimología , Ureasa/análisis , Factores de Edad , Proteínas Bacterianas/análisis , Niño , Preescolar , Recuento de Colonia Microbiana , Índice CPO , Ayuno , Femenino , Humanos , Concentración de Iones de Hidrógeno , Masculino , ARN Bacteriano/análisis , Saliva/microbiología , Factores Sexuales , Streptococcus/genética , Streptococcus mutans/aislamiento & purificaciónRESUMEN
BACKGROUND: Mesenteric vein thrombosis (MVT) is uncommon and accounts for 5-10% of all mesenteric ischemic events. In 80% of cases, an etiologic factor is found. The clinical presentation varies and the diagnosis is made based on imaging studies. The treatment involves anticoagulation alone or in combination with surgery. AIM: To describe the clinical characteristics of patients with MVT. PATIENTS AND METHODS: Retrospective and prospective review of all cases with MVT, treated between 1995-2001. The clinical presentation, imaging studies, treatment and outcome were evaluated. RESULTS: 29 cases of MVT were reviewed (14 females, age 56 +/- 15 years). Twenty two patients (76%) had recognizable risk factors. The main symptoms were abdominal pain (86%) and vomiting (55%). The diagnosis of acute mesenteric ischemia was suspected on admission only in 6 patients (21%). Thirteen patients underwent transabdominal color Doppler ultrasonography and the diagnosis was confirmed for 11 of these (85%). Twenty out of 24 patients (85%) studied with computed tomography, had positive signs of MVT. Twenty one patients (72%) received anticoagulation, 10 of whom also underwent surgery. Four patients (14%) received surgical treatment alone. Four patients were not treated. Seven patients (24%) died. CONCLUSIONS: MVT is difficult to identify. It is necessary to have a high degree of suspicion in patients who have risk factors. The diagnosis is made with imaging studies. The treatment consists of early anticoagulation and surgical intervention when indicated.
Asunto(s)
Oclusión Vascular Mesentérica/diagnóstico , Trombosis de la Vena/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/uso terapéutico , Femenino , Humanos , Masculino , Oclusión Vascular Mesentérica/tratamiento farmacológico , Oclusión Vascular Mesentérica/cirugía , Venas Mesentéricas , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo , Trombosis de la Vena/tratamiento farmacológico , Trombosis de la Vena/cirugíaRESUMEN
Background: Mesenteric vein thrombosis (MVT) is uncommon and accounts for 5-10percent of all mesenteric ischemic events. In 80percent of cases, an etiologic factor is found. The clinical presentation varies and the diagnosis is made based on imaging studies. The treatment involves anticoagulation alone or in combination with surgery. Aim: To describe the clinical characteristics of patients with MVT. Patients and methods: Retrospective and prospective review of all cases with MVT, treated between 1995-2001. The clinical presentation, imaging studies, treatment and outcome were evaluated. Results: 29 cases of MVT were reviewed (14 females, age 56 ± 15 years). Twenty two patients (76percent) had recognizable risk factors. The main symptoms were abdomianl pain (86percent) and vomiting (55percent). The diagnosis of acute mesenteric ischemia was suspected on admission only in 6 patients (21percent). Thirteen patients underwent transabdominal color Doppler ultrasonography and the diagnosis was confirmed for 11 of these (85percent). Twenty out of 24 patients (85percent) studied with computed tomography, had positive signs of MVT. Twenty one patients (72percent) recieved anticoagulation, 10 of whom also underwent surgery. Four patients (14percent) received surgical treatment alone. Four patients were not treated. Seven patients (24percent) died. Conclusions: MVT is difficult to identify. It is necessary to have a high degree of suspicion in patients who have risk factors. The diagnosis is made with imaging studies. The treatment consists of early anticoagulation and surgical intervention when indicated.
Asunto(s)
Adulto , Masculino , Humanos , Femenino , Anciano , Oclusión Vascular Mesentérica/cirugía , Oclusión Vascular Mesentérica/diagnóstico , Oclusión Vascular Mesentérica/tratamiento farmacológico , Trombosis de la Vena/cirugía , Trombosis de la Vena/diagnóstico , Trombosis de la Vena/tratamiento farmacológico , Anticoagulantes/uso terapéutico , Estudios Prospectivos , Estudios Retrospectivos , Factores de RiesgoRESUMEN
Based on favorable experiences with acupuncture for the treatment of hind limbs paralysis, lumbo-sacral alterations, and other spinal cord problems; a clinical trial, involving 40 dogs affected with wobbler syndrome was carried out. Patients were graded in three categories according to the severity of each case and then randomly divided in two groups. Both groups contained all three grades. Group 1 (20 dogs) was treated using orthodox medical and surgical interventions, while Group 2 (20 dogs) were treated mainly with electroacupuncture, and in few cases with surgical intervention as well. The study was carried out in a three-year period. Acupuncture treatments were given every other day delivering 150 to 300 mVolts at 125 Hz, equivalents to approximately 20 microAmps, in ten acupuncture points per treatment. Deep needle insertion was used. Overall per cent success in Group I was only 20%, while in group II the corresponding value was 85%. The number of acupuncture treatments required to achieve full recovery in Group II was dependent upon the severity of the case, as follows: Grade I: 18.5 +/- 2.5; Grade II: 25 +/- 5.4; and Grade III: 34 +/- 6.7 (r = 0.962). No adverse effects were observed with acupuncture. The use of this technique is proposed for large-scale clinical trials.
Asunto(s)
Enfermedades de los Perros/terapia , Electroacupuntura/veterinaria , Compresión de la Médula Espinal/veterinaria , Animales , Perros , Femenino , Masculino , Compresión de la Médula Espinal/terapia , Enfermedades de la Médula Espinal/terapia , Enfermedades de la Médula Espinal/veterinaria , SíndromeRESUMEN
A closed colony of Lutzomyia longipalpis was established with specimens collected in the Raposa - Serra do Sol indian reservoir, one of the main foci of visceral leishmaniasis in the State of Roraima, Brazil. Biological observations were made on four generations of a L. longipalpis colony with emphasis on productivity. Aspects studied were the number of laid and retained eggs, and the number of adults (male and female) per generation. During the four generations the percentage of engorged females that laid eggs varied from 64.2% (third generation-F3) to 90.3% (second generation-F2). The mean number of eggs laid per female varied from 23.6 (F3) to 39. 9 (first generation-F1). The maximum number of eggs laid per female varied from 84 (F3) to 124 (F1). The mean number of retained eggs per female was 12.7 (parental generation-P and F1) to 22.1 (F2). The number of females exceeded the number of males in all generations. However, significant difference for male/female ratio was found only for F3. Fecundity rates were between 42.1 (F3) and 58.3 (F2). From a total of 439 blood-fed females, 355 females laid 12,257 eggs that yield 5,354 adults (2,525 males and 2,829 females) in four generations. F2 presented maximum productivity and fecundity rates.
Asunto(s)
Oviposición/fisiología , Psychodidae/anatomía & histología , Razón de Masculinidad , Animales , Femenino , Fertilidad/fisiología , Masculino , Psychodidae/fisiologíaRESUMEN
OBJECTIVE: The objectives of the present study were: 1) To corroborate the increase in alcohol consumption in the female population registered by results from the National Surveys on Addictions (ENA), 1988 and 1993; and 2) to determine affected age groups, and obtain basic information on age of onset, amount consumed per event and drunkenness frequency in the adult population of Mexico City, as indicators to orient preventive measures. MATERIAL AND METHODS: A multi-stage, stratified household survey was applied. A total of 1,932 interviews was completed, subjects were between 18 and 65 years of age, with a response rate of 60.4%. The instrument was a modified version of the Composite International Psychiatric Interview (CIDI), which is a highly structured instrument, applicable by non-specialized personnel, although limited training is necessary. The alcohol section included questions on the age of the first drink, the frequency and amount consumed during each event and the drunkenness frequency during the last 12 months, among other variables. Median and percentage were obtained by sex and among age-cohorts. RESULTS: Of the total, 96.5% of men and 18.1% of women have consumed at least one drink in their lives. In average, age of onset is 16 years for men, and 18 years for women. Age group comparisons show a clear tendency to begin drinking at an earlier age, particularly in women. The growing trend indicated by ENA with respect to alcohol consumption in the feminine population and at a younger age was corroborated. Results indicated that, in average, 5 years after the age of onset, both men and women reach their highest quantities of alcohol consumption, which tend to be excessive. Additionally, high-risk drinking among women (five or more drinks per event) increased to be four times higher in a period of seven years, and with an apparent tendency to rise. Sixty percent of the drinking population reduced alcohol consumption before the age of 30, however, the remaining 40% continued to drink at the same rate, or even increased consumption, particularly among women. CONCLUSIONS: The age of onset of alcohol consumption has diminished, especially in women, showing tendencies towards abuse. Preventive programs should predominantly focus on young age groups with emphasis on the feminine population.
Asunto(s)
Consumo de Bebidas Alcohólicas/epidemiología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Prevalencia , Distribución por Sexo , Factores Sexuales , Encuestas y Cuestionarios , Salud UrbanaRESUMEN
OBJECTIVE: With the increased use of intracoronary stents, in-stent restenosis has become a clinically significant drawback in invasive cardiology. We retrospectively assessed the short- and long-term outcomes after excimer laser coronary angioplasty of in-stent restenosis. METHODS: Twenty-five patients with 33 incidents of in-stent restenosis treated with excimer laser coronary angioplasty (ELCA) were analyzed. Sixty-six percent were males, mean age of 73 +/- 11 years, and 83% were functional class III-IV (NYHA). ELCA was performed using 23 concentric and 10 eccentric catheters with a diameter of 1.6-2.2 mm, followed by balloon angioplasty (PTCA) and ultrasound monitoring. The procedure was performed in the following vessels: left anterior descending artery, 10; left circumflex artery, 8; right coronary artery, 6; left main coronary artery, 2; and venous bypass graft, 7. RESULTS: The ELCA was successful in 71% of the cases, and PTCA was 100% successful. The diameter of the treated vessels was 3.44 +/- 0.5 mm; the minimal luminal diameter (MLD) increased from 0.30 mm pre-ECLA to 1.97 mm post-ELCA, and to 2.94 mm post-PTCA (p < 0.001). The percent stenosis was reduced from 91.4 +/- 9.5% before ECLA to 42.3 +/- 14.9% after ELCA and to 14.6 +/- 9.3% after PTCA (p < 0.001). Seventeen (68%) patients were asymptomatic at 6 months and 15 (60%) at 1 year. New restenosis rates were 8/33 (24.2%) at 6 months and 9/33 (27.3%) at 12 months. CONCLUSION: ELCA is safe and effective for the treatment of in-stent restenosis. In the present sample, a slight increase in new restenotic lesions between 6 and 12 months was found.