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1.
Osteoporos Int ; 29(8): 1737-1745, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29713798

RESUMO

The incidence of hypocalcemia and bone mineral density (BMD) changes in end-stage renal disease (ESRD) patients on denosumab remains unclear. We performed this meta-analysis to assess the incidence of denosumab-associated hypocalcemia and effects of denosumab on BMD in ESRD patients. A literature search was conducted using MEDLINE, EMBASE, and Cochrane Database from inception through November 2017 to identify studies evaluating incidence of denosumab-associated hypocalcemia and changes in serum calcium, phosphate, alkaline phosphatase (ALP), parathyroid hormone (PTH), and BMD from baseline to post-treatment course of denosumab in ESRD patients. Study results were pooled and analyzed using a random-effect model. The protocol for this meta-analysis is registered with PROSPERO (International Prospective Register of Systematic Reviews; no. CRD42017081074). Six observational studies with a total of 84 ESRD patients were enrolled. The pooled estimated incidence of hypocalcemia during denosumab treatment was 42% (95% CI 29-55%, I2 = 0%). Hypocalcemia occurred approximately 7 to 20 days after the first dose and reached nadir of low calcium levels in the first 2 weeks up to 2 months. However, there were no significant changes in serum calcium or phosphate from baseline to post-treatment course (≥ 3 months after treatment) with mean differences [MDs] of 0.20 mg/dL (95% CI, - 0.30 to 0.69 mg/dL) and - 0.10 mg/dL (95% CI, - 0.70 to 0.49 mg/dL). There were significant reductions in ALP and PTH levels with standardized mean differences (SMDs) of - 0.65 (95% CI - 1.13 to - 0.16) and - 1.89 (95% CI - 3.44 to - 0.34), respectively. There were significant increases in T-scores with MDs of 0.39 (95% CI 0.10 to 0.69) and 0.79 (95% CI 0.60 to 0.98) for lumbar spine and femoral neck, respectively. Our study demonstrates the estimated incidence of denosumab-associated hypocalcemia in dialysis patients of 42%. From baseline to post-treatment course, although there are no differences in serum calcium and phosphate, our findings suggest significant reductions in ALP and PTH and a significant increase in BMD. Currently, denosumab should not be considered as the treatment of choice in ESRD patients until more safety and efficacy data are available.


Assuntos
Conservadores da Densidade Óssea/efeitos adversos , Densidade Óssea/efeitos dos fármacos , Denosumab/efeitos adversos , Hipocalcemia/induzido quimicamente , Falência Renal Crônica/sangue , Conservadores da Densidade Óssea/uso terapêutico , Cálcio/sangue , Denosumab/uso terapêutico , Humanos , Hipocalcemia/sangue , Falência Renal Crônica/complicações , Falência Renal Crônica/fisiopatologia , Estudos Observacionais como Assunto/métodos , Osteoporose/tratamento farmacológico , Osteoporose/etiologia
3.
Aliment Pharmacol Ther ; 47(1): 78-85, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28994122

RESUMO

BACKGROUND: It has been suggested that beta-blockers may increase mortality in patients with cirrhosis and refractory ascites but the effect of beta-blockers discontinuation or reinitiation has not been examined. AIMS: To compare, in hospitalised patients with cirrhosis and ascites, the effect of BB on survival and to examine the effect/predictors of beta-blockers discontinuation and reinitiation. METHODS: Sub-analysis of NACSELD (North American consortium for the study of end-stage liver disease, database containing prospective data on hospitalised patients with cirrhosis) data from 7 centres enrolling >100 patients with ascites. Data on BB discontinuation and reinitiation were collected by chart review. RESULTS: Seven hundred and sixteen patients, 307 (43%) on beta-blockers at admission and 366 (51%) with refractory ascites, were followed to death or hospital discharge. Beta-blocker use was associated with a lower white blood cell count at admission. Beta-blocker use in hospitalised patients with ascites was not associated with a higher mortality, even in those with refractory ascites. No significant changes in mean arterial pressure (MAP) were observed between groups. Discontinuation of beta-blockers (49%) was driven by low MAP, infection and acute kidney injury at time of discontinuation but was not associated with a higher mortality. Beta-blocker reinitiation occurred in 40% prior to discharge and was mainly driven by an increase in MAP. CONCLUSIONS: Beta-blocker use is safe in patients with cirrhosis and ascites (including those with refractory ascites) provided beta-blockers are discontinued in the presence of a low MAP and reinitiated once MAP reincreases. A potentially beneficial anti-inflammatory effect of beta-blockers is suggested.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Ascite/mortalidade , Cirrose Hepática/tratamento farmacológico , Idoso , Ascite/complicações , Doença Hepática Terminal/complicações , Feminino , Humanos , Cirrose Hepática/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
4.
Aliment Pharmacol Ther ; 45(2): 319-331, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27868217

RESUMO

BACKGROUND: Opioid use is epidemic in cirrhosis, which could precipitate hepatic encephalopathy (HE) potentially through gut dysbiosis and inflammation. AIM: To define the effect of opioids on readmissions and on gut microbiota composition and functionality. METHODS: Cohort 1 had 200 cirrhotic in-patients (with/without opioid use) followed prospectively through the index hospitalisation and 6 months post discharge. Readmissions (HE-related/unrelated) were compared between patients discharged on opioids compared to the rest, including using a multi-variable analysis. Cohort 2 consisted of 72 cirrhotics on chronic opioids who were age/model for end-stage liver disease (MELD) and prior HE-balanced with 72 cirrhotics not on opioids. Stool microbiota composition (multi-tagged sequencing), predicted functionality (PiCRUST), endotoxemia and systemic inflammation (IL-6, IL-17) were compared. RESULTS: Cohort 1: Chronic opioid use was statistically similar between those admitted with/without HE, and was judged to be an HE precipitant in <5% of cases during the index hospitalisation. Of the 144 patients alive at 6 months, 82 were readmitted. The opioid users had a significantly higher all cause (69% vs. 48%, P = 0.008), but not HE-related readmissions (30% vs. 41%, P = 0.30). On regression, opioid therapy and female gender were predictive of readmission independent of MELD score and previous HE. Cohort 2: Significant dysbiosis was noted in the opioid cohort, especially in HE+opioid patients with lower autochthonous taxa and Bacteroidaceae relative abundance. PiCRUST showed highest aromatic amino acid and endotoxin production in opioid users. Opioid users also had higher endotoxemia and IL-6 but not IL-17. CONCLUSION: Chronic opioid use in cirrhosis is associated with increased endotoxemia, dysbiosis and all-cause readmissions.


Assuntos
Analgésicos Opioides/uso terapêutico , Microbioma Gastrointestinal/efeitos dos fármacos , Cirrose Hepática/tratamento farmacológico , Readmissão do Paciente/estatística & dados numéricos , Disbiose/tratamento farmacológico , Disbiose/microbiologia , Endotoxemia/tratamento farmacológico , Endotoxemia/microbiologia , Fezes/microbiologia , Feminino , Encefalopatia Hepática/tratamento farmacológico , Encefalopatia Hepática/microbiologia , Humanos , Cirrose Hepática/microbiologia , Masculino , Pessoa de Meia-Idade , Alta do Paciente/estatística & dados numéricos
5.
J Nepal Health Res Counc ; 14(32): 18-26, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27426707

RESUMO

BACKGROUND: Alcohol consumption has grown up sharply over the past decades in Nepal. Conversely, little is known about this phenomenon among the urban poor. We assessed pattern, frequency, context, and type of alcohol consumption among the urban poor of Nepal. METHODS: We executed a cross-sectional study, taking 422 households from four squatter settlements of Kathmandu Valley. Modified Nepalese version standard questionnaire was used for data collection. Data was objectively analyzed in SPSS full version 19. RESULTS: The study reported 39.81% (95% CI: 32.41-47.21) current drinkers, with male (65.99%, 95% CI: 57.85-74.13) outnumbering female (16.89%, 95% CI: 4.98-28.80). One out of ten drinkers drank daily (male: 13.08%, female: 13.16%). A third (30.36%) of all current drinkers acknowledged drinking more than one type of alcohol (male: 28.46%, female: 36.84%). Nearly half (47.60%) of the drinkers drank in social gathering (male: 47.90%, female: 47.60%). Home was the place of drinking for nearly one-fifth (18.60%) of the drinkers. Males most commonly drank alcohol with their friends (34.60%), whereas female drank with family members (25.60%). Nearly half of the drinkers drank during evening hour (45.24%). Multivariable analysis detected likelihood of drinking 5.86 times (95% CI: 2.50-13.72) in male and 3.16 times (95% CI: 1.39-7.13) in those with family history of alcohol. CONCLUSIONS: We found high prevalence of alcohol consumption than the national average among the urban poor with a marked gender difference by pattern. Gender sensitive alcohol prevention and control programs need a greater start.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Pobreza , População Urbana , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nepal/epidemiologia , Inquéritos e Questionários , Adulto Jovem
6.
Blood Cancer J ; 6: e380, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26771806

RESUMO

Deregulated microRNA (miR)/transcription factor (TF)-based networks represent a hallmark of cancer. We report here a novel c-Myc/miR-23b/Sp1 feed-forward loop with a critical role in multiple myeloma (MM) and Waldenstrom's macroglobulinemia (WM) cell growth and survival. We have found miR-23b to be downregulated in MM and WM cells especially in the presence of components of the tumor bone marrow milieu. Promoter methylation is one mechanism of miR-23b suppression in myeloma. In gain-of-function studies using miR-23b mimics-transfected or in miR-23b-stably expressing MM and WM cell lines, we observed a significant decrease in cell proliferation and survival, along with induction of caspase-3/7 activity over time, thus supporting a tumor suppressor role for miR-23b. At the molecular level, miR-23b targeted Sp1 3'UTR and significantly reduced Sp1-driven nuclear factor-κB activity. Finally, c-Myc, an important oncogenic transcription factor known to stimulate MM cell proliferation, transcriptionally repressed miR-23b. Thus MYC-dependent miR-23b repression in myeloma cells may promote activation of oncogenic Sp1-mediated signaling, representing the first feed-forward loop with critical growth and survival role in myeloma.


Assuntos
Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , MicroRNAs/genética , Mieloma Múltiplo/genética , Proteínas Proto-Oncogênicas c-myc/genética , Fator de Transcrição Sp1/genética , Animais , Sequência de Bases , Sítios de Ligação , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/genética , Metilação de DNA , Modelos Animais de Doenças , Regulação para Baixo , Expressão Gênica , Perfilação da Expressão Gênica , Inativação Gênica , Genes Reporter , Humanos , MicroRNAs/química , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myc/química , Proteínas Proto-Oncogênicas c-myc/metabolismo , Interferência de RNA , RNA Mensageiro/química , RNA Mensageiro/genética , Fator de Transcrição Sp1/química , Fator de Transcrição Sp1/metabolismo
7.
Leukemia ; 30(2): 399-408, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26338273

RESUMO

The anti-CD38 monoclonal antibody SAR650984 (SAR) is showing promising clinical activity in treatment of relapsed and refractory multiple myeloma (MM). Besides effector-mediated antibody-dependent cellular cytotoxicity and complement-mediated cytotoxicity, we here define molecular mechanisms of SAR-directed MM cell death and enhanced anti-MM activity triggered by SAR with Pomalidomide (Pom). Without Fc-cross-linking agents or effector cells, SAR specifically induces homotypic aggregation (HA)-associated cell death in MM cells dependent on the level of cell surface CD38 expression, actin cytoskeleton and membrane lipid raft. SAR and its F(ab)'2 fragments trigger caspase 3/7-dependent apoptosis in MM cells highly expressing CD38, even with p53 mutation. Importantly, SAR specifically induces lysosome-dependent cell death (LCD) by enlarging lysosomes and increasing lysosomal membrane permeabilization associated with leakage of cathepsin B and LAMP-1, regardless of the presence of interleukin-6 or bone marrow stromal cells. Conversely, the lysosomal vacuolar H+-ATPase inhibitor blocks SAR-induced LCD. SAR further upregulates reactive oxygen species. Pom enhances SAR-induced direct and indirect killing even in MM cells resistant to Pom/Len. Taken together, SAR is the first therapeutic monoclonal antibody mediating direct cytotoxicity against MM cells via multiple mechanisms of action. Our data show that Pom augments both direct and effector cell-mediated MM cytotoxicity of SAR, providing the framework for combination clinical trials.


Assuntos
ADP-Ribosil Ciclase 1/antagonistas & inibidores , Anticorpos Monoclonais Humanizados/farmacologia , Apoptose/efeitos dos fármacos , Lisossomos/fisiologia , Glicoproteínas de Membrana/antagonistas & inibidores , Mieloma Múltiplo/tratamento farmacológico , Talidomida/análogos & derivados , ADP-Ribosil Ciclase 1/fisiologia , Actinas/química , Genes p53/fisiologia , Humanos , Glicoproteínas de Membrana/fisiologia , Microdomínios da Membrana/fisiologia , Mieloma Múltiplo/patologia , Espécies Reativas de Oxigênio/metabolismo , Talidomida/farmacologia
8.
Eur Spine J ; 23(11): 2385-92, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24740279

RESUMO

STUDY DESIGN: Noggin protein levels and spinal fusion rates were compared in a rabbit model after application of siRNA against BMP antagonist noggin in paraspinal muscle. OBJECTIVE: To test whether endogenous BMPs are sufficient to form bone in the absence of their antagonists, using noggin siRNA to interrupt the negative feedback loop on endogenous BMP within the paraspinal muscles in rabbits. Unused Posterolateral lumbar fusion is a standard surgical treatment for many spinal disorders, yet even under ideal conditions the rate of non-fusion approaches 25 %. BMPs are effective in promoting bone formation, and are inhibited by antagonists such as noggin. We have previously shown that in this model, endogenous BMPs are present and endogenous BMP antagonist noggin is strongly increased during spinal fusion. Previous studies have found that noggin siRNA enhanced spinal fusion in combination with supra-physiological amounts of exogenous BMP; however, the effect of the siRNA alone remains unknown. METHODS: A posterolateral intertransverse rabbit lumbar fusion was utilized, as established by Boden et al. SiRNA against noggin was electroporated into paraspinal muscle to determine its effect on fusion. Outcome measures included noggin protein expression, and assessment of spinal fusion at 6 weeks. RESULTS: SiRNAs were effective in reducing overexpressed noggin in vitro. Noggin protein was successfully knocked down in vivo for the initial 7 days in our rabbit model and returned to detectable levels by 4 weeks and to normal levels by 6 weeks. The overall fusion rate was not significantly enhanced compared to established controls from our earlier work (Tang et al.). CONCLUSIONS: Early noggin suppression does not appear to enhance the BMP activity sufficiently to significantly affect final fusion rates in our model.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas de Transporte/metabolismo , Vértebras Lombares/cirurgia , Músculos Paraespinais/metabolismo , Fusão Vertebral , Animais , Proteínas de Transporte/genética , Técnicas de Silenciamento de Genes , Modelos Animais , RNA Interferente Pequeno , Coelhos
9.
Leukemia ; 28(1): 155-65, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23588715

RESUMO

The key nuclear export protein CRM1/XPO1 may represent a promising novel therapeutic target in human multiple myeloma (MM). Here we showed that chromosome region maintenance 1 (CRM1) is highly expressed in patients with MM, plasma cell leukemia cells and increased in patient cells resistant to bortezomib treatment. CRM1 expression also correlates with increased lytic bone and shorter survival. Importantly, CRM1 knockdown inhibits MM cell viability. Novel, oral, irreversible selective inhibitors of nuclear export (SINEs) targeting CRM1 (KPT-185, KPT-330) induce cytotoxicity against MM cells (ED50<200 nM), alone and cocultured with bone marrow stromal cells (BMSCs) or osteoclasts (OC). SINEs trigger nuclear accumulation of multiple CRM1 cargo tumor suppressor proteins followed by growth arrest and apoptosis in MM cells. They further block c-myc, Mcl-1, and nuclear factor κB (NF-κB) activity. SINEs induce proteasome-dependent CRM1 protein degradation; concurrently, they upregulate CRM1, p53-targeted, apoptosis-related, anti-inflammatory and stress-related gene transcripts in MM cells. In SCID mice with diffuse human MM bone lesions, SINEs show strong anti-MM activity, inhibit MM-induced bone lysis and prolong survival. Moreover, SINEs directly impair osteoclastogenesis and bone resorption via blockade of RANKL-induced NF-κB and NFATc1, with minimal impact on osteoblasts and BMSCs. These results support clinical development of SINE CRM1 antagonists to improve patient outcome in MM.


Assuntos
Carioferinas/antagonistas & inibidores , Mieloma Múltiplo/terapia , Osteoclastos/patologia , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Humanos , Mieloma Múltiplo/patologia , Proteína Exportina 1
10.
Bioresour Technol ; 116: 290-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22522016

RESUMO

The filamentous, heterocystous, diazotrophic cyanobacterium, Anabaena torulosa was found to bind uranium from aqueous solutions containing 100 µM uranyl carbonate at pH 7.8. The uranyl sequestration kinetics exhibited (a) an initial rapid phase, binding 48% uranium within 30 min resulting in a loading of 56 mg U g(-1) of dry wt, followed by (b) a slower phase, binding 65% uranium with resultant loading of 77.35 mg U g(-1) in 24h. Energy Dispersive X-ray fluorescence spectroscopy of uranium loaded biomass revealed all components of UL X-rays (UL(l), UL(α), UL(ß1) and UL(ß2)). Heat killed cells or extracellular polysaccharides derived from live cells exhibited limited uranyl binding (~26%) highlighting the importance of cell viability for optimum uranyl binding. The present study revealed the involvement of acid soluble polyphosphates in uranium accumulation by this brackish water cyanobacterium.


Assuntos
Anabaena/metabolismo , Fixação de Nitrogênio/fisiologia , Urânio/metabolismo , Ácidos/química , Anabaena/citologia , Biodegradação Ambiental , Temperatura Alta , Viabilidade Microbiana , Polifosfatos/metabolismo , Solubilidade , Urânio/isolamento & purificação
11.
J Nepal Health Res Counc ; 8(2): 124-5, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21876578

RESUMO

Acute coronary syndrome in elderly can manifest with a variety of atypical presentation and may be associated with other comorbid conditions. We present an atypical presentation of ACS in an elderly left handed female presenting with sudden onset of slurred speech preceded by dizziness and vomiting. After through clinical examination and investigation she was managed as a case of non ST elevation myocardial infarction and ischaemic stroke.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Isquemia Encefálica/diagnóstico , Acidente Vascular Cerebral/diagnóstico , Síndrome Coronariana Aguda/patologia , Idoso , Isquemia Encefálica/patologia , Diagnóstico Diferencial , Erros de Diagnóstico , Feminino , Humanos , Acidente Vascular Cerebral/patologia
12.
J Comput Chem ; 31(4): 671-90, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19575467

RESUMO

The widely used CHARMM additive all-atom force field includes parameters for proteins, nucleic acids, lipids, and carbohydrates. In the present article, an extension of the CHARMM force field to drug-like molecules is presented. The resulting CHARMM General Force Field (CGenFF) covers a wide range of chemical groups present in biomolecules and drug-like molecules, including a large number of heterocyclic scaffolds. The parametrization philosophy behind the force field focuses on quality at the expense of transferability, with the implementation concentrating on an extensible force field. Statistics related to the quality of the parametrization with a focus on experimental validation are presented. Additionally, the parametrization procedure, described fully in the present article in the context of the model systems, pyrrolidine, and 3-phenoxymethylpyrrolidine will allow users to readily extend the force field to chemical groups that are not explicitly covered in the force field as well as add functional groups to and link together molecules already available in the force field. CGenFF thus makes it possible to perform "all-CHARMM" simulations on drug-target interactions thereby extending the utility of CHARMM force fields to medicinally relevant systems.


Assuntos
Simulação por Computador , Modelos Químicos , Pirrolidinas/química , Modelos Moleculares , Simulação de Dinâmica Molecular , Teoria Quântica , Software
13.
Bioresour Technol ; 100(7): 2176-81, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19070485

RESUMO

A marine, unicellular cyanobacterium, Synechococcus elongatus strain BDU/75042 was found to sequester uranium from aqueous systems at pH 7.8. The organism could remove 72% (53.5 mg U g(-1) dry weight) of uranium from test solutions containing 100 microM uranyl carbonate within 1h. The equilibrium data fitted well in the Langmuir isotherm thus suggesting a monolayer adsorption of uranium on the cyanobacterial biomass and predicted the maximum adsorption capacity of 124 mg U g(-1) dry weight. Light and scanning electron microscopy coupled with energy dispersive X-ray fluorescence (EDXRF) spectroscopy confirmed the uranyl adsorption by this organism. Most of the bound uranium was found to be associated with the extracellular polysaccharides (EPS) suggesting its interaction with the surface active ligands. Fourier transform infrared (FT-IR) spectroscopy suggested the amide groups and the deprotonated carboxyl groups on the cyanobacterial cell surface were likely to be involved in uranyl adsorption. The cell bound uranium could be released by washing with ethylene diamine tetraacetic acid (EDTA) or 0.1N HCl. The X-ray diffraction (XRD) analyses revealed the identity of uranium deposits associated with the cell biomass as uranyl carbonate hydrate. The study revealed the potential of this cyanobacterium for harvesting uranium from natural aquatic environments.


Assuntos
Água do Mar/microbiologia , Synechococcus/metabolismo , Urânio/isolamento & purificação , Adsorção/efeitos dos fármacos , Biodegradação Ambiental/efeitos dos fármacos , Biomassa , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Synechococcus/citologia , Synechococcus/efeitos dos fármacos , Synechococcus/ultraestrutura , Urânio/farmacologia , Difração de Raios X
14.
Water Environ Res ; 78(7): 661-70, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16929635

RESUMO

A two-stage membrane bioreactor was used to treat dissolved-air-flotation pretreated, high-strength pet food wastewater characterized by oil and grease concentrations of 50 000 to 82 000 mg/L and total chemical oxygen demand (COD) and five-day biochemical oxygen demand (BOD5) concentrations of 100 000 and 80 000 mg/L, respectively, to meet stringent surface discharge criteria (i.e., BOD5, total suspended solids [TSS], and ammonium-nitrogen [NH4(+)-N] of < 10 mg/L at an overall hydraulic retention time of 6.3 days). Organic contaminants were removed primarily in the first stage, followed by almost complete removal of ammonia in the second stage. Despite a rise in poorly biodegradable COD in the second stage, overall removal of TSS, BOD5, COD, and ammonia was 100, 99.9, 95.2, and 99.7%, respectively, thus readily achieving the required criteria. Consistent nitrite accumulation over a period of more than 100 days, even at dissolved oxygen concentrations of more than 2.5 mg/L, was remarkable. A residual alkalinity requirement for nitrification was quantified. Membrane performance was extensively studied in this work.


Assuntos
Ração Animal , Reatores Biológicos , Membranas Artificiais , Eliminação de Resíduos Líquidos/métodos , Animais , Animais Domésticos , Nitritos/metabolismo , Oxigênio/metabolismo , Purificação da Água
15.
Theor Appl Genet ; 113(5): 931-42, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16847662

RESUMO

The grass inflorescence is the primary food source for humanity, and has been repeatedly shaped by human selection during the domestication of different cereal crops. Of all major cultivated cereals, sorghum [Sorghum bicolor (L.) Moench] shows the most striking variation in inflorescence architecture traits such as branch number and branch length, but the genetic basis of this variation is little understood. To study the inheritance of inflorescence architecture in sorghum, 119 recombinant inbred lines from an elite by exotic cross were grown in three environments and measured for 15 traits, including primary, secondary, and tertiary inflorescence branching. Eight characterized genes that are known to control inflorescence architecture in maize (Zea mays L.) and other grasses were mapped in sorghum. Two of these candidate genes, Dw3 and the sorghum ortholog of ramosa2, co-localized precisely with QTL of large effect for relevant traits. These results demonstrate the feasibility of using genomic and mutant resources from maize and rice (Oryza sativa L.) to investigate the inheritance of complex traits in related cereals.


Assuntos
Flores/genética , Locos de Características Quantitativas , Sorghum/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Cruzamentos Genéticos , DNA de Plantas/genética , Flores/crescimento & desenvolvimento , Flores/ultraestrutura , Genes de Plantas , Ligação Genética , Marcadores Genéticos , Fenótipo , Sorghum/crescimento & desenvolvimento , Sorghum/ultraestrutura
16.
J Hazard Mater ; 129(1-3): 194-203, 2006 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-16202515

RESUMO

A novel paradigm using pre-denitrification process is presented to optimize an existing system of two-stage MBRs treating high strength pet food wastewater. Successive reduction of organics in the 1st stage and almost complete nitrification in the 2nd stage generated effluent meeting stringent surface discharge criteria i.e. BOD5, TSS and NH4+ -N of < 10 mg/L at an overall HRT of 6.3 days. Pre-anoxic zone was created by a submerged coil in the path of influent to the 1st stage. Final effluent and the 1st stage mixed liquor were recirculated to the coil. With prevailing high denitrification rates, more than 94% of the recirculated nitrates were denitrified in less than 15 min of effective anoxic residence time. At a recycle ratio of 3:1, total nitrogen was reduced by 84%, aeration energy by 25% and the external alkalinity requirement by 65%, enhancing economical viability of the system.


Assuntos
Ração Animal , Reatores Biológicos , Resíduos Industriais , Compostos de Nitrogênio/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Animais , Animais Domésticos
17.
Water Res ; 39(18): 4299-308, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16221482

RESUMO

Although thermophilic treatment systems have recently gained considerable interest, limited information exists on the comparative performances of membrane-coupled bioreactors (MBR) at thermophilic and conventional conditions. In this study aerobic MBRs operating at room temperature (20 degrees C) and at lower thermophilic range (45 degrees C) were investigated for the treatment of dissolved air flotation (DAF) pretreated pet food wastewater. The particular wastewater is characterized by oil and grease (O & G) concentrations as high as 6 g/L, COD of 51 g/L, BOD of 16 g/L and volatile fatty acid (VFA) of 8.3 g/L. The performances of the two systems in terms of COD, BOD and O & G removal at varying hydraulic retention time (HRT) are compared. COD removal efficiencies in the thermophilic MBR varied from 75% to 98% and remained constant at 94% in the conventional MBR. The O & G removal efficiencies were 66-86% and 98% in the thermophilic and conventional MBR, respectively. Interestingly, high concentrations of VFA were recorded, equivalent to 50-73% of total COD, in the thermophilic MBR effluent. The observed yield in the thermophilic MBR was 40% of that observed in the conventional MBR.


Assuntos
Reatores Biológicos , Indústria de Processamento de Alimentos , Ultrafiltração , Purificação da Água/métodos , Aerobiose , Amônia/isolamento & purificação , Ração Animal , Animais , Animais Domésticos , Biodegradação Ambiental , Biotecnologia/métodos , Resíduos Industriais , Membranas Artificiais , Óleos/análise , Temperatura
18.
Appl Biochem Biotechnol ; 118(1-3): 47-63, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15304738

RESUMO

Coal is the most important nonrenewable energy source of fossil origin. It is also the most common fuel in thermal power plants. However, during coal incineration in power plants, high sulfur content of coal poses serious environmental problems owing to sulfur dioxide emission. We studied the application of microbial methods for removal of sulfur from three types of high sulfur coals-two samples collected from Assam and Rajasthan in India and one from Libiaz, Poland. These coal samples were desulfurized using indigenous Acidithiobacillus sp. After investigation of the effect of various parameters, the conditions optimized for the maximum removal of total sulfur (91.87% for lignite, 63.13% for Polish coal, and only 9.44% for Assam coal) were as follows: initial pH of 1.5 (2.5 in the case of Assam coal), particle size of 45 micro, pulp density of 2% (w/v), incubation period of 30 d at -35 degrees C in presence of 44.2 g/L of ferrous sulfate in the media with shaking at 140 rpm. Poor removal of sulfur in the case of Assam coal was owing to extensive precipitation of jarosites. In addition, the sulfur in Assam coal is mostly found in organic form, which is difficult to remove with Acidithiobacillus sp. The removal of sulfur from the three coal samples was demonstrated with photomicrographic studies.


Assuntos
Acidithiobacillus/metabolismo , Carvão Mineral , Enxofre/metabolismo , Compostos Férricos/metabolismo , Concentração de Íons de Hidrogênio , Ferro/metabolismo , Tamanho da Partícula , Sulfetos/metabolismo
19.
Bioresour Technol ; 95(1): 77-83, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15207299

RESUMO

A field experiment was conducted on deep vertisols of Bhopal, India to evaluate the manural potential of three organic manures: farmyard manure (FYM), poultry manure (PM), phosphocompost (PC) vis-a-vis 0%, 75% and 100% recommended dose of fertilizer-NPK and to find out the most productive cropping system at various combinations of organic manures and chemical fertilizers. The seed yield of intercrop soybean (population converted to 100%) was 8.7% less than sole soybean whereas the grain yield of intercrop sorghum was 9.5% more than that of sole sorghum. However, the productivity in terms of soybean equivalent yield (SEY) was relatively high in intercropping system. The increasing NPK dose from 0% to 100% significantly improved SEY in sole sorghum and soybean/sorghum intercropping system and the integrated use of organics and inorganics recorded significantly more SEY than inorganics. The effect of nutrient management followed the order; 75% NPK + 5 t FYM ha(-1) > 75% NPK + 1.5 t PM ha(-1) > 75% NPK + 5 t PC ha(-1) > 100% NPK. Sorghum, both as sole and intercrop, responded more to PM while soybean to FYM. Application of 75% NPK in combination with PM or FYM or PC to preceding rainy season crops (soybean and sorghum) and 75% NPK to wheat produced significantly higher grain yield of wheat than those in inorganics and control indicating noticeable residual effect on the succeeding wheat crop and saving of 25% fertilizer-NPK. The effect of PC on rainy season crops was not as prominent as those of FYM and PM, but its residual effect on grain yield of wheat was comparable to those two organic manures. Among the cropping systems, soybean as preceding crop recorded the highest seed yield of wheat and was on a par with that of soybean/sorghum intercropping system. The yield of wheat following sorghum was the lowest. The total system productivity (TSP) was the highest in sorghum + soybean-wheat system and the lowest in the soybean-wheat system.


Assuntos
Agricultura/métodos , Produtos Agrícolas , Fertilizantes , Esterco , Animais , Bovinos , Índia , Fósforo , Aves Domésticas , Chuva , Estações do Ano , Glycine max , Triticum , Clima Tropical
20.
Bioresour Technol ; 88(3): 197-206, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12618041

RESUMO

An experiment was conducted during 1998-1999, in a deciduous forest located in the semi-arid tropics of central India, to evaluate the suitability of different forest litters as food material for the tropical epigeic earthworms i.e. Eisenia fetida (Savigny), Perionyx excavatus (Perrier) and Dicogaster bolaui (michaelsen). The aim was to examine the influence of these earthworms on the decomposition processes of three types of forest litters i.e. Tectona grandis (teak), Madhuca indica (mahua) and Butea monosperma (palas), on the maintenance of quality in a vermicomposting system, and to assess the effect of applications of in situ prepared vermicomposts on the growth of forest trees. The results indicated that T. grandis litter was the most suitable food material for the earthworms possibly because it contained high reserves of mineral nutrients. Comparisons of the survival and reproduction rates of the three epigeic earthworm species indicated that a higher reproduction rate was maintained for E. fetida compared to P. excavatus and D. bolaui in the decomposition of these forest litters. The rates of growth and population increases of E. fetida approximately doubled after 12 weeks of litter decomposition. The litter decomposition process was associated strongly with the quality of the materials and their chemical composition. Irrespective of earthworm inoculations, the levels of available nutrient such as NH(4)-N, NO(3)-N, available P and K increased significantly (pM. indica litter compost>B. monosperma litter compost. The mature decomposed litter had lower C/N ratios (11.3-24.8:1), water-soluble carbon (0.30-0.58%), water-soluble carbohydrates (0.35-0.71%) and larger cation exchange capacity/total organic carbon ratios than the values in the parent forest litter. The lignin content increased with maturation with a concomitant decrease in cellulose resulting in higher lignin/cellulose ratios. Application of all three vermicomposts to forest trees significantly improved their heights and diameters over those of control trees, although the increases were lower than those resulting from the chemical fertilizer applications. However, soil biological activities i.e. soil respiration, soil microbial biomass carbon and dehydrogenase activity were greater by application of vermicomposts over that after application of inorganic fertilizer in a new plantation of T. grandis.


Assuntos
Oligoquetos/fisiologia , Árvores , Animais , Meio Ambiente , Fertilizantes , Alimentos , Dinâmica Populacional , Microbiologia do Solo , Especificidade da Espécie , Taxa de Sobrevida , Árvores/crescimento & desenvolvimento , Árvores/metabolismo
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