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1.
Braz J Biol ; 83: e274991, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37909589

RESUMEN

The objective of this study was to evaluate the water status, photosynthetic pigments, and photochemical efficiency of mini watermelon plants under salt stress and phosphate fertilization. The experiment was conducted in pots under greenhouse conditions in Pombal, PB, Brazil. The experimental design used was randomized blocks in a 5 × 4 factorial scheme, with five levels of electrical conductivity of irrigation water - ECw (0.3, 1.3, 2.3, 3.3, and 4.3 dS m-1) and four doses of phosphorus (60, 80, 100, and 120% of the recommendation), with three replicates. The relative water content in the tissues decreased with the increase in ECw levels in all phosphorus doses, with decreases of 7.05, 7.81 and 8.83% per unit increase in ECw, in plants fertilized with 80, 100 and 120% P2O5. On the other hand, ECw levels increased electrolyte leakage, regardless of phosphorus doses of the recommendation. The synthesis of photosynthetic pigments and the quantum efficiency of photosystem II were inhibited by increasing water salinity from 0.3 dS m-1 in plants grown under phosphorus doses above 60% of the recommendation. Water salinity from 0.3 dS m-1 reduced chlorophyll b contents, initial, maximum, and variable fluorescence of mini watermelon plants, with a decrease of 11.86, 4.51, 4.53, and 4.54% per unit increment of ECw, respectively.


Asunto(s)
Citrullus , Fosfatos , Fotosíntesis , Aguas Salinas , Fósforo
2.
Braz J Biol ; 83: e275322, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37729213

RESUMEN

Several studies have been conducted evaluating the management of fertilizers as strategies to mitigate the deleterious effects of salt stress, so the objective of this work was to evaluate the quality of 'Crioula' guava seedlings under irrigation with water of different salinity levels and fertilized with combinations of nitrogen and potassium. The experiment was performed in a protected (screened) environment using a randomized block design and analyzed in a 5 × 4 factorial scheme, with four replicates, with the plot formed by two plants. The treatments were formed from the combination of the factor electrical conductivity of irrigation water (ECw 0.3, 1.1, 1.9, 2.7 and 3.5 dS m-1), with the factor combinations (C) of nitrogen (N) and potassium (K2O) doses, being C1 = 70% N + 50% K2O, C2 = 100% N + 75% K2O, C3= 130% N + 100% K2O and C4= 160% N + 125% K2O. The recommended dose of 100% N and K, respectively, was 541.1 mg N dm-3 soil and 798.6 mg K dm-3 soil. The combinations of N and K fertilization corresponding to 70% N + 50% K2O and 100% N + 75% K2O of the recommended doses promoted greater growth of 'Crioula' guava seedlings. Water with ECw of 2.1 dS m-1 promotes the formation of quality 'Crioula' guava seedlings.


Asunto(s)
Psidium , Plantones , Salinidad , Nitrógeno , Potasio , Suelo , Agua
3.
J Hazard Mater ; 340: 417-426, 2017 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-28743073

RESUMEN

This paper investigates the feasibility of applying in-situ Bioremediation (ISB) to three sites contaminated with vinyl chloride and/or chlorinated alkanes such as 1,2-DCA and 1,1,2-TCA, presenting distinct hydrogeological settings and history of contaminant loading. Biotransformation of these compounds is well established in laboratory studies and pure cultures. Due to confidential aspects, however, few field data are available to support real case studies to the predictability of their fate and lifetime in soil and groundwater. Bio-Trap® In Situ Microcosm (ISM) studies were performed in selected monitoring wells, and consisted of a control unit which simulated Monitored Natural Attenuation conditions and other units which were amended with either lactate, emulsified vegetable oil (EVO) or molasses as electron donors. For wells with moderate Dhc counts, the ISM study demonstrated that electron donor addition could stimulate further growth of Dhc and enhance reductive dechlorination. Conversely, for wells with high population counts, substrate addition did not alter results significantly. Site-specific determining factors that most influenced the biodegradation results were microbial activity, soil texture and presence of organic matter, site pH, redox conditions and presence of free phase.


Asunto(s)
Dicloruros de Etileno/metabolismo , Cloruro de Vinilo/metabolismo , Contaminantes Químicos del Agua/metabolismo , Biodegradación Ambiental , Agua Subterránea
4.
Artículo en Inglés | MEDLINE | ID: mdl-27418308

RESUMEN

BACKGROUND: Inspiratory esophagogastric junction (EGJ) pressure is lower in gastroesophageal reflux disease (GERD) and patients fail to increase EGJ pressure during the inspiratory effort. The aim of this study was to assess the EGJ activity during inspiratory maneuvers (high-resolution manometry, HRM) and the crural diaphragm (CD) thickness (endoscopic ultrasound, EUS) in GERD. METHODS: Twenty esophagitis patients (average age 45 years, 7 grade A, 13 grade B) had HRM and EUS. Forty-three controls were recruited; 30 had HRM (average age 33 years), and 13 had EUS (average age 40 years). The EGJ contractility index (EGJ-CI) (mm Hg×cm) was measured during normal respiration and two inspiratory maneuvers: without and with inspiratory loads of 12, 24, and 48 cmH2 O (TH-maneuvers). A composite metric for TH-maneuvers ("EGJ total activity") was defined as the product of the maximal EGJ pressure and the length of its aboral excursion during the maneuver (mm Hg×cm). The CD thickness (cm) was measured during expiration (12 MHz). KEY RESULTS: Expiratory lower esophageal sphincter pressure and integrated relaxation pressure were lower in GERD. The EGJ-CI and the "EGJ total activity" were lower in GERD during TH-maneuvers (48-cmH2 O load: 168.4 ± 13.8 vs 114.8 ± 9.6, P=.006). Patients failed to sustain the inspiratory CD activity across the 12 and 48-cmH2 O efforts. The CD was thinner in GERD patients (0.37 ± 0.03 vs 0.49 ± 0.04, P=.02). The CD thickness correlated with the increment in the "EGJ total activity" in GERD without a hiatal hernia (r=.702, P=.016, n=11). CONCLUSIONS & INFERENCES: There are anatomical changes and functional failure of the CD in esophagitis patients supporting the possibility of a skeletal muscle deficiency in GERD.


Asunto(s)
Diafragma/diagnóstico por imagen , Diafragma/fisiopatología , Esofagitis/diagnóstico por imagen , Esofagitis/fisiopatología , Unión Esofagogástrica/diagnóstico por imagen , Unión Esofagogástrica/fisiopatología , Adulto , Anciano , Diafragma/anatomía & histología , Unión Esofagogástrica/anatomía & histología , Femenino , Reflujo Gastroesofágico/diagnóstico por imagen , Reflujo Gastroesofágico/fisiopatología , Humanos , Masculino , Persona de Mediana Edad
5.
Dentomaxillofac Radiol ; 41(7): 541-7, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22988312

RESUMEN

OBJECTIVES: A wide variety of manifestations is presented in patients with Gaucher's disease (GD), including bone, haematology and visceral disturbances. This study was conducted to ascertain the main maxillofacial abnormalities by means of clinical survey, panoramic and cone beam CT (CBCT); to compare the patient's group with an age-sex matched control group; and to correlate clinical and radiological data. METHODS: Ten patients previously diagnosed with GD were submitted to clinical and radiological surveys (CBCT and panoramic radiographs). The examination consisted of anamnesis, extra- and intraoral examinations and analyses of each patient's records. Imaging data were collected from the point of view of 3 observers, and the results compared with a healthy group (20 individuals) by means of statistical analysis (Fisher's exact test). RESULTS: Gaucher patients had significantly more manifestations than otherwise healthy carriers. The most prevalent findings were enlarged marrow spaces, generalized osteopenia and effacement of jaw structures (mandibular canal, lamina dura and mental foramen). Here we describe a case in which thickening of the maxillary sinus mucosa was observed on CBCT rather than opacification of the sinus as seen on panoramic radiographs. Pathological fractures, root resorption and delay on tooth eruption were not observed. CONCLUSIONS: A poor relationship could be observed between clinical and radiological data. Patients showed important bone manifestations, which require careful diagnostic and surgical planning whenever necessary. Although panoramic radiographs have shown significant differences, CBCT is more effective in pointing out differences between patients and a control group, thus showing it as an important tool for evaluation of Gaucher patients.


Asunto(s)
Enfermedad de Gaucher/diagnóstico por imagen , Enfermedades Maxilomandibulares/diagnóstico por imagen , Enfermedades Dentales/diagnóstico por imagen , Adolescente , Adulto , Enfermedades Óseas Metabólicas/diagnóstico por imagen , Enfermedades de la Médula Ósea/diagnóstico por imagen , Estudios de Casos y Controles , Niño , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Masculino , Cóndilo Mandibular/diagnóstico por imagen , Enfermedades Mandibulares/diagnóstico por imagen , Enfermedades Maxilares/diagnóstico por imagen , Seno Maxilar/diagnóstico por imagen , Mucosa Nasal/diagnóstico por imagen , Radiografía Panorámica , Adulto Joven
6.
Aliment Pharmacol Ther ; 35(5): 577-86, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22229478

RESUMEN

BACKGROUND: Visceral tone supposedly affects gut sensitivity in irritable bowel syndrome (IBS). Sildenafil increases nitric oxide and influences visceral compliance. AIM: To evaluate the effects of sildenafil tone inhibition on rectal sensitivity. METHODS: Eight controls and 21 IBS patients (Rome II) were enrolled in a double-blind study, after dosing with placebo or sildenafil (50 mg p.o.). Thresholds for first sensation, first desire to defecate, pain and supraliminar pain were the sensory endpoints, measured with a barostat and 600-mL rectal bag. Pain (100-mm VAS) and depression-anxiety (Hamilton questionnaire) were scored. RESULTS: Irritable bowel syndrome rectal compliance and sensory-endpoint thresholds were similar to controls. Five IBS patients had pain threshold lower than controls 95% confidence interval (hypersensitive). Depression score was greater in IBS than controls (11.9 ± 1.3 vs. 6.3 ± 2.5, P = 0.036). In IBS, pain intensity was nonsignificantly higher (37.6 ± 5.3 mm vs. 23.4 ± 8.5 mm, P = 0.064) and supraliminar pain intensity was greater (45.6 ± 5.4 mm vs. 25.9 ± 5.1 mm, P = 0.044) than controls. IBS rectal relaxation increased volume (155.4 ± 41.3 mL vs. 118.8 ± 47.7 mL, P = 0.004) and tension (193.1 ± 118.6 mmHg mL(-1) vs. 133.2 ± 98.1 mmHg mL(-1) , P = 0.019) for triggering first desire to defecate but not for other perceptions. Sildenafil increased volume for both first desire to defecate and pain in the hypersensitive IBS patients. Sildenafil increased rectal compliance only in diarrhoea-IBS. Mixed-IBS obtained higher anxiety (12.9 ± 1.3 vs. 5.9 ± 3.1, P < 0.05) and depression scores (13.9 ± 1.9 vs. 6.3 ± 2.5, P < 0.05) and reported more intense supraliminar pain (53.6 ± 9.8 mm vs. 25.9 ± 5.1 mm, P < 0.05) than controls. CONCLUSIONS: Rectal relaxation following dosing with sildenafil 50 mg increased the first desire to defecate threshold in IBS as a whole, but decreased pain only in the hypersensitive subset. Mixed-IBS presented higher supraliminar pain and anxiety-depression scores.


Asunto(s)
Síndrome del Colon Irritable/tratamiento farmacológico , Trastornos del Humor/tratamiento farmacológico , Tono Muscular/efectos de los fármacos , Inhibidores de Fosfodiesterasa 5/uso terapéutico , Piperazinas/uso terapéutico , Recto/efectos de los fármacos , Sulfonas/uso terapéutico , Adulto , Defecación/efectos de los fármacos , Método Doble Ciego , Femenino , Humanos , Síndrome del Colon Irritable/complicaciones , Masculino , Persona de Mediana Edad , Trastornos del Humor/complicaciones , Tono Muscular/fisiología , Óxido Nítrico/metabolismo , Dimensión del Dolor/métodos , Umbral del Dolor/efectos de los fármacos , Umbral del Dolor/fisiología , Escalas de Valoración Psiquiátrica , Purinas/uso terapéutico , Índice de Severidad de la Enfermedad , Citrato de Sildenafil , Estadísticas no Paramétricas
7.
J Contam Hydrol ; 94(3-4): 277-92, 2007 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-17728007

RESUMEN

A groundwater vulnerability and risk mapping assessment, based on a source-pathway-receptor approach, is presented for an urban coastal aquifer in northeastern Brazil. A modified version of the DRASTIC methodology was used to map the intrinsic and specific groundwater vulnerability of a 292 km(2) study area. A fuzzy hierarchy methodology was adopted to evaluate the potential contaminant source index, including diffuse and point sources. Numerical modeling was performed for delineation of well capture zones, using MODFLOW and MODPATH. The integration of these elements provided the mechanism to assess groundwater pollution risks and identify areas that must be prioritized in terms of groundwater monitoring and restriction on use. A groundwater quality index based on nitrate and chloride concentrations was calculated, which had a positive correlation with the specific vulnerability index.


Asunto(s)
Modelos Teóricos , Abastecimiento de Agua , Brasil , Toma de Decisiones , Lógica Difusa , Sistemas de Información Geográfica , Humanos , Medición de Riesgo , Contaminantes del Agua
8.
Arch Pediatr ; 9(1): 7-13, 2002 Jan.
Artículo en Francés | MEDLINE | ID: mdl-11865553

RESUMEN

UNLABELLED: In France, most of children suffering from congenital toxoplasmosis have an infraclinic or moderate type at birth. This study aimed at evaluating, on the mid term, tolerance and results of postnatal treatment previously given in severe toxoplasmosis. METHODS: A retrospective study considered 46 children with a mild or moderate congenital toxoplasmosis treated over 12 months with sulfadiazine-pyrimethamine and treatment was completed since three months. RESULTS: Five children suffered from a lesion of chorioretinitis during treatment and two after. After a mean follow-up of 27.1 months, ten children (21.7% 95%CI [12.1-35.9]) had at least one ocular injury. Specific IgG titers and immune load were diminished to become almost non-existent at the end of the year of treatment (respectively p < 10(-5) and p = 0.0005). No thrombocytopenia was observed. Twenty-three children (50%) had at least one episode of neutropenia < 1000/mm3, 14 had only one, nine presented two or more installment. None was followed by an infection. CONCLUSION: This therapeutic pathway is more demanding but shorter than those usually offered when associating pyrimethamine-sulfadiazine. Yet, it does give identical result on the mid term. Longer follow-up is needed to appreciate. Active molecule on cysts should be introduced.


Asunto(s)
Antiprotozoarios/administración & dosificación , Pirimetamina/administración & dosificación , Sulfadiazina/administración & dosificación , Toxoplasmosis Congénita/tratamiento farmacológico , Factores de Edad , Análisis de Varianza , Quimioterapia Combinada , Femenino , Humanos , Inmunoglobulina G/análisis , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Factores de Tiempo , Toxoplasmosis Congénita/inmunología
9.
Arch Pediatr ; 8(1): 66-77, 2001 Jan.
Artículo en Francés | MEDLINE | ID: mdl-11218587

RESUMEN

We review the available data on the possible role of breast-feeding in hepatitis C virus (HCV) transmission to infants of HCV-RNA-positive mothers. Current knowledge about HCV excretion through breast milk, HCV infection of breast-fed infants by mothers contaminated after delivery, and vertical transmission risk to infants breast-fed by chronic HCV viremic mothers are presented. Vertical transmission risk by breast-feeding HCV-RNA-positive mothers is unclear: no study has been performed with the aim and the required methodology to evaluate HCV transmission risk related to breast-feeding duration. Recommendations to HCV-RNA-positive mothers who wish to breast-feed their infant are discussed in light of present knowledge about HCV secretion in breast milk, mother-to-infant HCV transmission, and historical records on vertical transmission of other viruses to infants breast-fed by their viremic mothers.


Asunto(s)
Lactancia Materna/efectos adversos , Hepatitis C/transmisión , Transmisión Vertical de Enfermedad Infecciosa , Humanos , Recién Nacido
11.
Arch Fr Pediatr ; 50(7): 553-9, 1993.
Artículo en Francés | MEDLINE | ID: mdl-7516144

RESUMEN

BACKGROUND: The survival and outcome of infants with bronchopulmonary dysplasia (BD) depend on the patient's maturity, the severity of the BD and nutritional problems. This study evaluates the specific role of chronic pulmonary failure in the growth and development of infants recovering from BD. POPULATION AND METHODS: 88 infants admitted for BD from January 1984 to December 1988, having gestational age from 25 to 41 weeks 5 days (mean: 29) and birth weight from 680 to 3,400 g (mean: 1,195) were studied. All infants were given respiratory support for 6 to 914 days (mean 84) and oxygen therapy for 28 to 1,232 days (mean: 119). 29 infants were given corticosteroids for more than 1 month. The outcome of the 80 infants with gestational ages of less than 33 weeks was compared to that of 272 infants with the same gestational age but not suffering from BD on their 28th day. The infants in both groups were examined at 2 years of age and classified as: a) handicapped (neurologic deficit, IQ < 80, hearing loss, blindness, convulsions); b) doubtful (transitory neurology dysfunction); c) normal. RESULTS: Of the 88 infants still living at the age of 28 days, 19 died before the age of 2 years: 16 of the 64 surviving infants who could be followed until the age of 2 years were classified as handicapped, 13 were considered doubtful and 35 were normal. The more significant risk factors for neurodevelopmental impairment were: a) the presence of porencephaly and/or ventricular dilatation on brain ultrasonography; b) head circumference < -2 SD at the end of hospital stay; c) oxygen therapy and hospitalization > 5-6 months. The group of infants with BD had a higher death rate (24% vs. 3.7 in the group without BD) and more frequent neurodevelopmental impairment at gestational ages of > 31-32 weeks. CONCLUSIONS: BD is an extra risk for the survival and neurodevelopment of infants with gestational age > 31 weeks.


Asunto(s)
Displasia Broncopulmonar/fisiopatología , Trastornos Psicomotores/etiología , Displasia Broncopulmonar/complicaciones , Displasia Broncopulmonar/mortalidad , Preescolar , Discapacidades del Desarrollo/etiología , Femenino , Estudios de Seguimiento , Edad Gestacional , Humanos , Lactante , Recién Nacido , Masculino , Enfermedades del Sistema Nervioso/etiología , Pronóstico , Insuficiencia Respiratoria/complicaciones , Factores de Riesgo , Factores de Tiempo
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