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1.
J Environ Radioact ; 264: 107187, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37186982

ABSTRACT

To determine their transfer factors, activity concentrations of natural radionuclides were measured in the leaves and acorns of holm oak (Quercus ilex L.) trees collected from seven locations with different soil properties and radionuclide activity concentrations. The chemical and mineralogical compositions of the soils were also analysed to investigate the effect these had on radionuclide absorption by the trees. Soil chemistry showed significant effects on radionuclide incorporation into Quercus ilex L. tissues. A significant relationship was established between activity concentrations and soil content of Ca and P with 238U and 226Ra in the leaves and acorns of Quercus ilex L. Differentiated transfer was found for 40K, which showed greater transfer to the leaves than the other radionuclides. The activity concentration of U and 226Ra was higher in the fruits than in the leaves, with the opposite effect being observed for 40K. The risk of U and 226Ra transfer into the food chain through acorn consumption by livestock is predicted to increase in soils poor in Ca and rich in P.


Subject(s)
Quercus , Radiation Monitoring , Fruit , Quercus/metabolism , Lead/analysis , Soil/chemistry , Plant Leaves/chemistry , Trees
2.
Rev Neurol (Paris) ; 178(10): 1031-1040, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36137828

ABSTRACT

The goal of cerebrovascular pathology treatment is most often to angiographically eradicate a lesion with the lowest probability of morbidity. Destructive strategies using parent vessel occlusion are less commonly considered in the modern era. We review principles of parent vessel occlusion for treatment of cerebrovascular pathology and select cases to demonstrate these principles. Many common cerebrovascular conditions have been safely and effectively treated with destructive strategies including intracranial aneurysms, traumatic craniocervical vascular injuries, and oncologic indications such as carotid blowout. Avoiding procedural morbidity in these procedures involves assessment of collaterals distal to a planned parent vessel occlusion, determination of this arterial segment's eloquence, prevention of distal migration of endovascular devices or thrombus, and prevention of stump emboli. An algorithm for case selection and method of destructive technique versus a reconstructive approach can be used. Destructive strategies for treating cerebrovascular pathology are still relevant and can be applied safely in appropriately selected cases.


Subject(s)
Cerebrovascular Disorders , Embolization, Therapeutic , Intracranial Aneurysm , Humans , Cerebral Angiography , Embolization, Therapeutic/methods , Intracranial Aneurysm/therapy , Cerebrovascular Disorders/therapy , Postoperative Complications/therapy
3.
Sci Total Environ ; 759: 143571, 2021 Mar 10.
Article in English | MEDLINE | ID: mdl-33248777

ABSTRACT

The purpose of this work was to study the factors affecting the absorption of U by plants growing on the spoil tip of an abandoned mine in western Spain. The plant species were selected based on how palatable they were to livestock and were sampled for four consecutive years during which, we also recorded rainfall data. The factors related to the plants studied were the leaf size and the percentage and characteristics of the arbuscular mycorrhizae (AM) fungi present in their roots. Our results showed a correlation between the annual rainfall and the U concentration in the plants. The percentage of mycorrhization and AM vesicles is a predominant factor in the uptake of U by plants. Spergularia rubra (L.) J.Presl & C.Presl, which is resistant to mycorrhization, contained higher U concentrations relative to the plants that grew with AM mycorrhization. The absorption curves of the different plants studied indicated that these plants were tolerant to 238U from 875 Bq kg-1 (70 mg kg-1), with a hormesis effect below that concentration. The annual U removal was 0.068%, suggesting that AM are responsible for limiting the incorporation of U into the food chain, favouring its retention in the soil and preventing its dispersion.


Subject(s)
Mycorrhizae , Uranium , Mycorrhizae/chemistry , Plant Roots/chemistry , Plants , Soil , Spain , Uranium/analysis
5.
Arch Soc Esp Oftalmol (Engl Ed) ; 95(3): 120-129, 2020 Mar.
Article in English, Spanish | MEDLINE | ID: mdl-31980324

ABSTRACT

OBJECTIVE: To analyse the safety and effectiveness of the oral administration of a commercialised supplement containing R-alpha lipoic acid, taurine, vitamins C and E, lutein, zeaxanthin, zinc, copper and docosahexaenoic acid, in patients with primary open angle glaucoma (POAG), and in control subjects. MATERIAL AND METHODS: A prospective study of cases and controls was carried out, including 30 participants of both genders that were divided into: POAG Group (n=15) and a control group (CG; n=15), assigned to the oral intake of NuaDHA preparations Vision® (1 pill/day)+NuaDHA 1000 (2 pills/day) for 6 months. Participants were interviewed, ophthalmologically examined, and peripheral blood was taken for routine analysis and the determination of the pro-oxidant (malondialdehyde) and total antioxidant status. Statistical analysis was performed using the SPSS 22.0 program. RESULTS: After 6 months of supplementation, there was a significant increase in the plasma total antioxidant status (1.073±0.090mM vs 1.276±0.107mM, P=.028), along with a parallel decrease in malondialdehyde (7.066±1.070µM vs 2.771±0.462µM, P=.005) in the POAG group. The malondialdehyde also decreased in the control group (6.17±1.336 vs. 2.51±0.391, P=.028). The Schirmer test improved (20-30%) and the subjective dry eye signs/symptoms noticeably decreased in the POAG group versus the CG. CONCLUSIONS: Formulations containing antioxidant vitamins, R-alpha lipoic acid and docosahexaenoic acid, administered for 6 consecutive months, counteracted the oxidative stress by further stabilising the morphological/functional parameters of both the ocular surface and the glaucoma, without presenting with adverse effects or intolerances.


Subject(s)
Antioxidants/administration & dosage , Glaucoma, Open-Angle/drug therapy , Thioctic Acid/administration & dosage , Administration, Oral , Adult , Aged , Case-Control Studies , Dietary Supplements , Female , Humans , Male , Middle Aged , Prospective Studies
7.
Environ Pollut ; 258: 113825, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31874441

ABSTRACT

The establishment of a screening index would be a powerful tool to decide whether abandoned uranium mining areas should be rehabilitated or decommissioned. Thus, in this work we established a radiological index which uses the activity concentrations of different groups of gamma emitters from the natural radioactive series of 238U, 235U, and 232Th, as well as 40K and 137Cs. These activity concentrations were calculated by using the absorbed gamma radiation dose value of 175 nGy h-1 specified in the U.S. Code of Federal Regulations. We studied our index in an abandoned uranium mining area in Salamanca, Western Spain, and found that the most influential factors in this area were the presence of organic matter in the soil and the possible effect that plants and fungi may have on the retention of these aforementioned radionuclides. In addition, the results showed that contaminants are migrating in an easterly direction in line with the prevailing wind direction and we were able to identify areas in which the radiological risk is likely high. The mean effective dose rate was 2.51 ± 0.98 mSv y-1 which was equivalent to the levels obtained in previous works.


Subject(s)
Radiation Monitoring , Soil Pollutants, Radioactive , Uranium , Mining , Spain , Spectrometry, Gamma , Thorium
9.
Zygote ; 26(5): 417-423, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30460886

ABSTRACT

SummaryThis study investigated the in vitro culture of bovine follicles included in ovarian tissue for 2 or 6 days (D2 or D6), with the addition of different concentrations of follicle-stimulating hormone (FSH) (0, 10, 50, 100 or 200 ng/ml). Data were compared for follicular development, morphological integrity and diameter of follicles and oocytes. Ovaries (n = 10) from Nelore cows (n = 5) were divided into fragments (n = 11 per ovary) and were immediately fixed in Bouin's solution (D0) or were individually cultured for 2 or 6 days in one of the described concentrations of FSH and then processed for histology. Compared with the rates of follicular development at D2 for minimal essential medium (MEM) (75.0%) and 50 ng/ml of FSH (71.1%), the best rates of follicular development at D2 were obtained with 10 (84.7%), 100 (87.5%) and 200 ng/ml of FSH (85.0%; P<0.05). After 6 days of cultivation, there were no differences among treatments regarding follicular growth. The morphological integrity of preantral follicles was better maintained by 100 ng/ml FSH for 2 and 6 days of cultivation (51.2 and 40.4%, respectively; P<0.05) than that for MEM (D2: 30.9%, D6: 20.8%), 10 (D2: 39.2%, D6: 22.8%), 50 (D2: 30.4%, D6: 28.8%) and 200 ng/ml FSH (D2: 45.2%, D6: 36.8%). FSH at 100 ng/ml provided the highest mean diameter averages: 34.5±10.8 µm at D2 and 33.2±12.5 µm at D6 (P<0.05). We concluded that the medium supplemented with 100 ng/ml FSH during in vitro culture provided appropriate conditions for the development and morphological integrity of preantral follicles in cattle.


Subject(s)
Follicle Stimulating Hormone/administration & dosage , Ovarian Follicle/drug effects , Ovarian Follicle/growth & development , Animals , Cattle , Dose-Response Relationship, Drug , Female , Follicle Stimulating Hormone/pharmacology , Ovarian Follicle/cytology , Tissue Culture Techniques
10.
Arch Soc Esp Oftalmol (Engl Ed) ; 93(5): 211-219, 2018 May.
Article in English, Spanish | MEDLINE | ID: mdl-29398232

ABSTRACT

OBJECTIVE: To identify genes involved in the pathogenic mechanisms of non-proliferative diabetic retinopathy (NPDR), among which include oxidative stress, extracellular matrix changes, and/or apoptosis, in order to evaluate the risk of developing this retinal disease in a type2 diabetic (DM2) population. MATERIAL AND METHODS: A case-control study was carried out on 81 participants from the Valencia Study on Diabetic Retinopathy (VSDR) of both genders, with ages 25-85years. They were classified into: (i)DM2 group (n=49), with DR (+DR; n=14) and without DR (-DR; n=35), and (ii)control group (GC; n=32). The protocols included a personal interview, standardised ophthalmological examination, and blood collection (to analyse the DNA for determining the gene expression (TP53, MMP9, and SLC23A2) in the study groups. Statistical analyses were performed using the SPSS v22.0 program. RESULTS: The TP53 and MMP9 genes showed a higher expression in the DM2 group compared to the GC, although the difference was only significant for the MMP9 gene (TP53: 10.40±1.20 vs. 8.23±1.36, P=.084; MMP9: 1.45±0.16 vs. 0.95±0.16, P=.036), and the SLC23A2 gene showed a significant lower expression in the DM2 vs CG (5.58±0.64 vs. 11.66±1.90, P=.026). When sub-dividing the DM2 group according to the presence of retinopathy, the expression of the TP53, MMP9 and SLC23A2 genes showed significant differences between the DM2-RD, DM2+RD and GC groups (TP53: 9.95±1.47 vs. 11.52±2.05 vs. 8.23±1.36, P=.038; MMP9: 1.47±0.20 vs. 1.41±0.27 vs. 0.95±0.16, P=.021; SLC23A2: 5.61±0.77 vs. 5.51±1.21 vs. 11.66±1.90, P=.018). CONCLUSIONS: Genes involved in extracellular matrix integrity (MMP9) and/or apoptosis (TP53), could be considered potential markers of susceptibility to the development/progression of NPDR. Interestingly, the SLC232A2 gene (ascorbic acid transporter) can be considered a protector of the risk of the development/progression of the retinopathy.


Subject(s)
Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/genetics , Diabetic Retinopathy/genetics , Genetic Association Studies , Adult , Aged , Aged, 80 and over , Case-Control Studies , Female , Humans , Male , Middle Aged , Spain
11.
Theriogenology ; 105: 169-173, 2018 Jan 01.
Article in English | MEDLINE | ID: mdl-28982027

ABSTRACT

The effect of different concentrations of alpha lipoic acid (ALA) on the development and morphology of preantral follicles, as well as the proliferative activity of granulosa cells, was assessed after short-term culture. Ovaries (n = 5) of five seasonal anestrous mares were harvested in a local abattoir. At the laboratory, nine ovarian fragments (5 × 5 × 1 mm) from each animal were used. One fragment was immediately fixed in Bouin and subjected to histological and immunohistochemistry (proliferating cell nuclear antigen, PCNA) analyses (noncultured group; D0 = day 0). The other eight fragments were cultured in situ for two (D2) or six (D6) days in MEM+ or MEM+ plus ALA (50, 100, or 250 µM). After culture, fragments were subjected to histology and PCNA analyses. After two days of culture, ALA 50 and ALA 100 had the greatest (P < 0.05) percentage of normal primordial follicles (97.2 and 95.1%, respectively), when compared to other groups, and did not differ (P > 0.05) from the fresh noncultured control group. Furthermore, the total percentage of normal follicles was greater (P < 0.05) in the ALA 50 and ALA 100 than in the MEM-D2 group. After six days of culture, the highest (P < 0.05) proliferative activity of granulosa cells in developing follicles was observed for the groups MEM+ (92.9%), ALA 50 (100%), and ALA 100 (96.4%). In conclusion, the results of this study demonstrated that (1) ALA 50 and ALA 100 preserved the morphological integrity of equine primordial follicles for up two days of culture, and (2) granulosa cells of developing follicles enclosed in ovarian tissue and cultured for up to six days in MEM+ with or without ALA were highly stained by PCNA.


Subject(s)
Horses/physiology , Ovarian Follicle/drug effects , Ovarian Follicle/physiology , Thioctic Acid/pharmacology , Tissue Culture Techniques/veterinary , Animals , Female , Immunohistochemistry , Ovarian Follicle/cytology
12.
Reprod Domest Anim ; 52(5): 899-904, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28580717

ABSTRACT

This study investigated the effects of different concentrations of FSH (10, 50, 100 and 200 ng/ml) in supplemented MEM+ on the development of equine pre-antral follicles that were cultured in vitro for 2 or 6 days. The ovaries (n = 5) from mares in seasonal anoestrus were collected from a local abattoir. Ten ovarian tissue fragments of approximately 3 × 3 × 1 mm were obtained from each animal. The fragments were cultured in situ for 2 days (D2) or 6 days (D6) in MEM+ or MEM+ supplemented with FSH at four different concentrations, establishing the following 11 groups: control (D0); MEM + (D2); MEM + (D6); MEM + 10 ng/ml of FSH (D2); MEM + 10 ng/ml of FSH (D6); MEM + 50 ng/ml of FSH (D2); MEM + 50 ng/ml of FSH (D6); MEM + 100 ng/ml of FSH (D2); MEM + 100 ng/ml of FSH (D6); MEM + 200 ng/ml of FSH (D2); and MEM + 200 ng/ml of FSH (D6). Follicles were observed in only 9.65% (388 of 4,018) of the histological sections. Of the 861 follicles evaluated, 488 were in the primordial stage, and 373 were in various developmental stages; 59.7% were morphologically normal. Regarding the integrity of the pre-antral follicles, the groups with 100 ng/ml FSH of 2-days culture as well as 50, 100 and 200 ng/ml FSH of 6-days culture provided the best results. In conclusion, the in vitro culture of abattoir-derived equine ovarian fragments presented better morphological integrity when supplemented with FSH for 6 days, in comparison with the MEM culture group. However, no clear effects were observed with FSH regarding the promotion of activation from a primordial to a developing follicle.


Subject(s)
Follicle Stimulating Hormone/pharmacology , Horses , Ovarian Follicle/drug effects , Tissue Culture Techniques/veterinary , Anestrus , Animals , Culture Media , Female , Ovarian Follicle/growth & development , Tissue Culture Techniques/methods
13.
Reprod Domest Anim ; 52(5): 836-841, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28580754

ABSTRACT

The goal of this study was to determine the distribution of pre-antral follicles in the ovarian parenchyma of mares. For Experiment 1, each ovary was cut longitudinally at the greater curvature, performing two hemiovaries. After that, six fragments from each hemiovary were obtained, resulting in 12 fragments, which were divided into the innermost region of the parenchyma, the middle region and the outermost region. All the three obtained sections were cut transversally to obtain two fragments from each one. For Experiment 2, each ovary also submitted to a longitudinal cut on the greater curvature, forming two hemiovaries. Each hemiovary was sectioned into four symmetrical fragments, resulting in eight fragments per ovary. The fragments were related as being near to or far from the ovulatory fossa. The fragments of both experiments were immediately fixed in Carnoy for 12 hr and kept in 70% ethanol for 24 hr. Follicles were classified according to the stages of development and for morphological integrity according to oocyte morphology and granulosa cells. After the histological assessment, a total of 1,130 follicles were visualized from Experiment 1, being 1,054 (93.3%) primordial follicles and 76 (4.7%) follicles in development. The innermost region had the highest percentage of pre-antral follicles compared to the other regions (p < .05). The middle and outermost regions showed higher percentages of intact primordial and developing follicles than the innermost region (p < .05). Considering Experiment 2, 938 follicles were found, being 894 (95.3%) primordial and 44 (4.7%) follicles in development. The region near the ovulatory fossa presented higher (58.7%; 551 of 938) follicular concentration compared to the region far from the ovulatory fossa (41.3%; 387 of 938; p < .05). As a conclusion, distribution of pre-antral follicles in the equine ovary has a specific pattern through the parenchyma. Also, the follicular integrity differed in the studied ovarian areas.


Subject(s)
Horses , Ovarian Follicle/anatomy & histology , Ovary/anatomy & histology , Animals , Female , Granulosa Cells , Oocytes , Ovarian Follicle/physiology
15.
Theriogenology ; 84(5): 750-5, 2015 Sep 15.
Article in English | MEDLINE | ID: mdl-26074067

ABSTRACT

The aim of this study was to evaluate the effects of different concentrations of ascorbic acid (25, 50, and 100 µg/mL) in supplemented minimum essential medium (MEM+) on the development of equine preantral follicles that were cultured in vitro for 2 or 6 days. The contralateral ovaries (n = 5) from five mares in seasonal anestrus were collected from a local abattoir. Nine ovarian tissue fragments of approximately 5 × 5 × 1 mm were obtained from each animal. One fragment was immediately fixed and subjected to histologic analysis (control group; Day 0), and the other eight were placed in PBS supplemented with penicillin (200 IU/mL) and streptomycin (200 mg/mL) at 4 °C for 1 hour (during transport to the laboratory). The fragments were cultured in situ for 2 days (D2) or 6 days (D6) in MEM+ or MEM+ plus ascorbic acid at three different concentrations, establishing the following nine groups: control; MEM+ (D2); MEM+ (D6); MEM+ 25 µg/mL of ascorbic acid (D2); MEM+ 25 µg/mL of ascorbic acid (D6); MEM+ 50 µg/mL of ascorbic acid (D2); MEM+ 50 µg/mL of ascorbic acid (D6); MEM+ 100 µg/mL of ascorbic acid (D2); and MEM+ 100 µg/mL of ascorbic acid (D6). The preantral follicles were classified according to their stage (primordial, primary, secondary, or antral) and their morphology (normal or abnormal). Slides (n = 951) including 4450 histologic sections were evaluated. Follicles were observed in only 4.85% (216 of 4450) of the histologic sections. Of the 407 follicles evaluated, 120 were in the primordial stage and 287 were in different developmental stages; additionally, 43.5% were morphologically normal. After 6 days of culture, the groups cultured with 50 and 100 µg/mL of ascorbic acid differed in terms of follicular development compared with the other groups. On the basis of occurrence of follicular development and the presence of viable follicles, it can be concluded that a positive effect of culture for 6 days in MEM+ supplemented with 50 and 100 µg/mL of ascorbic acid was observed on equine ovarian fragments.


Subject(s)
Ascorbic Acid/pharmacology , Cell Culture Techniques/veterinary , Horses/physiology , Ovarian Follicle/drug effects , Animals , Female , In Vitro Oocyte Maturation Techniques , In Vitro Techniques/veterinary , Oocyte Retrieval/veterinary , Ovarian Follicle/growth & development
16.
Av. diabetol ; 25(1): 21-26, ene.-feb. 2009. tab, ilus
Article in English | IBECS | ID: ibc-59254

ABSTRACT

The identifi cation of insulin receptor substrate (IRS) proteins in the 1990srepresents a key phase of diabetes research as it has enabled ourpresent understanding of the molecular basis of insulin and insulin-likegrowth factor (IGF) action. The generation of mice with targeted deletionsof the four major IRS proteins has revealed invaluable information aboutthe biological functions of these signaling molecules and has providednovel insights into the role of defective insulin signaling in the developmentof diabetes and metabolic diseases. Irs1-defi ciency in mice causesreduced body size, beta cell hyperplasia, and increased life-span. Disruptionof Irs2 has demonstrated that this branch of the insulin/IGF signalingcascade has an important role in peripheral insulin action and pancreaticbeta-cell growth and function. Global disruption of IRS2 signalingin mice causes diabetes due to failed beta cell compensation in the presenceof peripheral insulin resistance. Gene targeting of Irs3 or Irs4 didnot produce remarkable phenotypes suggesting that either they play veryspecifi c roles in limited tissues or that their absence may be compensatedfor by other signaling mechanisms. A complete understanding ofthe cellular events mediated by IRS1 and IRS2 will reveal new strategiesto prevent or cure diabetes and other metabolic diseases(AU)


Subject(s)
Animals , Mice , Receptor, Insulin/genetics , Signal Transduction/genetics , Diabetes Mellitus/genetics , Models, Animal , Phenotype
17.
Water Sci Technol ; 54(2): 223-9, 2006.
Article in English | MEDLINE | ID: mdl-16939106

ABSTRACT

The production of small amounts of well-stabilized biological sludge is one of the main advantages of upflow anaerobic sludge bed (UASB) reactors over aerobic wastewater treatment systems. In this work, sludge produced in three pilot-scale UASB reactors used to treat sewage under subtropical conditions was assessed for both stability and specific methanogenic activity. Stability of primary sludge from settling tanks and digested sludge from conventional sludge digesters was also measured for comparison purposes. Kinetic parameters like the hydrolysis rate constant and the decay rate constant were calculated. High stability was observed in sludge from UASB reactors. Methanogenic activity in anaerobic sludges was relatively low, probably due to the low organic matter concentration in influent sewage. Knowledge on sludge growth rate, stability, and activity might be very useful to optimize sludge management activities in full-scale UASB reactors.


Subject(s)
Sewage , Anaerobiosis , Hydrolysis , Kinetics , Methane/biosynthesis , Pilot Projects , Sewage/microbiology , Tropical Climate
18.
Curr Pharm Biotechnol ; 4(1): 21-37, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12570680

ABSTRACT

Excessive cell proliferation contributes to the pathobiology of human diseases with a high health and socio-economic impact, including cancer and vascular occlusive diseases (e. g., atherosclerosis, in-stent restenosis, transplant vasculopathy, and vessel bypass graft failure). Recent advances in the understanding of the molecular networks governing the hyperplastic growth of tumors and vascular obstructive neointimal lesions have provided new perspectives for preventive and therapeutic strategies against these disorders. Mammalian cell proliferation requires the activation of several cyclin-dependent protein kinases (CDKs). Postranslational activation of CDKs is a complex process that involves their association with regulatory subunits called cyclins. The activity of CDK/cyclin holoenzymes is negatively regulated through their interaction with members of the CDK family of inhibitory proteins (CKIs). Moreover, over fifty low molecular weight pharmacological CDK inhibitors that target the ATP-binding pocket of the catalytic site of CDKs have been identified. In this review, we will discuss the use of pharmacological and gene therapy strategies against CDK/cyclins in animal models and clinical trials of cancer and cardiovascular disease.


Subject(s)
Cardiovascular Diseases/enzymology , Cyclin-Dependent Kinases/antagonists & inhibitors , Cyclins/antagonists & inhibitors , Enzyme Inhibitors/therapeutic use , Growth Inhibitors/therapeutic use , Neoplasms/enzymology , Animals , Cardiovascular Diseases/drug therapy , Cyclin-Dependent Kinases/metabolism , Cyclins/metabolism , Humans , Neoplasms/drug therapy
19.
Water Sci Technol ; 45(10): 243-8, 2002.
Article in English | MEDLINE | ID: mdl-12188552

ABSTRACT

The performance of a sewage treatment system consisting of a settler followed by an Upflow Anaerobic Sludge Bed (UASB) reactor is described. Mean ambient and sewage temperature were 16.5 and 21.6 degrees C, respectively. Total Chemical Oxygen Demand (CODt) concentration averaged 224.2 and 152.6 mg/L, for raw and settled sewage, respectively. The effluent concentration was 68.5 mgCODt/L. Total and suspended COD removal efficiencies of approximately 70 and 80%, respectively, have been observed in the system at a mean Hydraulic Retention Time (HRT) of 2 + 5 h. Maximum COD removal efficiency was achieved in the UASB reactor when upflow velocity (Vup) was 0.43 m/h (HRT = 6 h). Mean Specific Methanogenic Activity (SMA) and Volatile Suspended Solids (VSS) concentration in the granular sludge bed were 0.11 gCOD-CH4/gVSS.d and 30.0 gVSS/Lsludge, respectively. SMA was inversely related to VSS concentration, and both parameters varied along the sludge bed height. The Solids Retention Time (SRT) in the reactor was 450 days. Sludge characteristics have not been affected by changes of up to one month in Vup in the range 0.28-0.85 m/h (HRT 3-9 h). This system or two UASB reactors in series could be an alternative for sewage treatment under moderate temperature conditions.


Subject(s)
Bacteria, Anaerobic/physiology , Bioreactors , Euryarchaeota/physiology , Sewage/microbiology , Oxygen/chemistry , Pilot Projects , Sewage/chemistry , Temperature , Tropical Climate , Waste Disposal, Fluid/methods
20.
Rev. chil. pediatr ; 72(6): 496-503, nov.-dic. 2001. tab, graf
Article in Spanish | LILACS | ID: lil-313231

ABSTRACT

Se estudio la asociación entre la residencia rural o urbana y el crecimiento inicial de lactantes nacidos pretérmino (AEG) en el Hospital Herminda Martín de Chillán, Chile. Se estudiaron prospectivamente hasta los 4 meses de vida, 80 lactantes nacidos entre enero y septiembre de 1995 (35 urbano y 45 rural), con peso de nacimiento <2 500 g y edad gestacional < 36 semanas. En los consultorios de atención primaria donde se controlaron se aplicó encuesta socioeconómica a la madre y se registro mensualmente peso y talla. Los niños rurales tendieron a crecer menos que los urbanos en los primeros 4 meses (13,6 vs, 14,4 cm, ns). En ambos grupos el menor crecimiento se asoció con estatura materna < 1,55 m (p< 0,0009). Entre los nacidos con más de 2 000 g los rurales crecieron menos en talla que los urbanos (12,7 vs 15,4 cm p < 0,0002). Concluimos que los lactantes nacidos prematuros en Chillán, de procedencia rural, tienen un menor crecimiento que los urbanos ya desde los primeros meses de vida


Subject(s)
Humans , Female , Pregnancy , Infant , Infant, Newborn , Infant, Premature , Rural Population/statistics & numerical data , Urban Population/statistics & numerical data , Growth , Nutritional Status , Prospective Studies , Social Class , Socioeconomic Factors , Weight by Height
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