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1.
Environ Monit Assess ; 196(1): 87, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38147204

RESUMEN

The production for crude oil usually leads to contamination of the soil with trace metals and organic contaminants from spilled petroleum. Organic contaminants were generally paid more attention than trace metals in the oilfield pollution. Many studies have investigated the impacts of some petroleum hydrocarbon pollutants, however, the impacts and risk assessment of trace metals remain largely unexplored. Moreover, under some circumstances, the risks associated with trace metals are not necessarily lower than those associated with organic contaminants. This study aimed to investigate methods to evaluate the possible risks associated with 11 trace metals (Ti, Ba, Sr, Rb, V, Li, Mo, Co, Cs, Bi, and Tl) in soil and biota samples from the Shengli Oilfield using ICP-MS. The results showed that 11 trace metals in the surface soils exceeded the local background levels. The geo-accumulation index (Igeo) indicated that the soils had light-moderate to moderate contamination levels, with higher Igeo value of Ba, V, Li, Mo, Co, and Cs. The individual potential ecological risk indices ([Formula: see text]) demonstrated moderate Bi and Tl pollution in soils. Comparatively, the [Formula: see text] is recommended for the risk assessment of trace metals on the ecosystem around the oilfield area. Mo, Bi, and Sr easily accumulate in plants, as reflected by their bioaccumulation factor. Ti, Ba, V, Li, Co, Cs, Bi, and Tl exhibited considerable biomagnification, particularly in birds. In this study, trace metals showed considerable bioaccumulation and biomagnification, and the risks of these trace metals on the ecosystem around oilfield production area need more attention.


Asunto(s)
Petróleo , Oligoelementos , Bioacumulación , Ecosistema , Yacimiento de Petróleo y Gas , Monitoreo del Ambiente , Suelo
2.
J Colloid Interface Sci ; 646: 118-128, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37187045

RESUMEN

HYPOTHESIS: Construction of dual gatekeepers-functionalized mesoporous organic silica nanoparticles (MONs) with both physical and chemical mechanisms for modulated drug delivery properties provides one solution to the extracellular stability vs. intracellular high therapeutic efficiency of MONs that hold great potential for clinical translations. EXPERIMENTS: We reported herein facile construction of diselenium-bridged MONs decorated with dual gatekeepers, i.e., azobenzene (Azo)/polydopamine (PDA) for both physical and chemical modulated drug delivery properties. Specifically, Azo can act as a physical barrier to block DOX in the mesoporous structure of MONs for extracellular safe encapsulation. The PDA outer corona serves not only as a chemical barrier with acidic pH-modulated permeability for double insurance of minimized DOX leakage in the extracellular blood circulation but also for inducing a PTT effect for synergistic PTT and chemotherapy of breast cancer. FINDINGS: An optimized formulation, DOX@(MONs-Azo3)@PDA resulted in approximately 1.5 and 2.4 fold lower IC50 values than DOX@(MONs-Azo3) and (MONs-Azo3)@PDA controls in MCF-7 cells, respectively, and further mediated complete tumor eradication in 4T1 tumor-bearing BALB/c mice with insignificant systematic toxicity due to the synergistic PTT and chemotherapy with enhanced therapeutic efficiency.


Asunto(s)
Nanopartículas , Neoplasias , Ratones , Animales , Dióxido de Silicio/química , Doxorrubicina/química , Nanopartículas/química , Sistemas de Liberación de Medicamentos , Neoplasias/tratamiento farmacológico , Fototerapia , Liberación de Fármacos
3.
Curr Pharm Des ; 22(4): 506-13, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26517529

RESUMEN

The development of slow release nano-sized carriers for efficient antineoplastic drug delivery with a biocompatible and biodegradable pectin-based macromolecular pro-drug for tumor therapy has been reported in this study. Pectin-doxorubicin conjugates (PDC), a macromolecular pro-drug, were prepared via an amide condensation reaction, and a novel amphiphilic core-shell micell based on a PDC macromolecular pro-drug (PDC-M) was self-assembled in situ, with pectin as the hydrophilic shell and doxorubicin (DOX) as the hydrophobic core. Then the chemical structure of the PDC macromolecular pro-drug was identified by both Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy ((1)H-NMR), and proved that doxorubicin combined well with the pectin and formed macromolecular pro-drug. The PDC-M were observed to have an unregularly spherical shape and were uniform in size by scanning electron microscopy (SEM). The average particle size of PDC-M, further measured by a Zetasizer nanoparticle analyzer (Nano ZS, Malvern Instruments), was about 140 nm. The encapsulation efficiency and drug loading were 57.82% ± 3.7% (n = 3) and 23.852% ±2.3% (n = 3), respectively. The in vitro drug release behaviors of the resulting PDC-M were studied in a simulated tumor environment (pH 5.0), blood (pH 7.4) and a lysosome media (pH 6.8), and showed a prolonged slow release profile. Assays for antiproliferative effects and flow cytometry of the resulting PDC-M in HepG2 cell lines demonstrated greater properties of delayed and slow release as compared to free DOX. A cell viability study against endothelial cells further revealed that the resulting PDC-M possesses excellent cell compatibilities and low cytotoxicities in comparison with that of the free DOX. Hemolysis activity was investigated in rabbits, and the results also demonstrated that the PDC-M has greater compatibility in comparison with free DOX. This shows that the resulting PDC-M can ameliorate the hydrophobicity of free DOX. This work proposes a novel strategy for in-situ one-step synthesis of macromolecular pro-drugs and fabrication of a core-shell micelle, demonstrating great potential for cancer chemotherapy.


Asunto(s)
Doxorrubicina/síntesis química , Portadores de Fármacos/síntesis química , Sistemas de Liberación de Medicamentos/métodos , Micelas , Pectinas/síntesis química , Profármacos/síntesis química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Química Farmacéutica , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacología , Portadores de Fármacos/farmacología , Femenino , Células Hep G2 , Humanos , Sustancias Macromoleculares/síntesis química , Masculino , Nanopartículas , Pectinas/farmacología , Profármacos/farmacología , Conejos
4.
Fish Shellfish Immunol ; 34(1): 167-72, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23123639

RESUMEN

Imidazole derivative KK-42 is well known as the insect growth regulator. Here we find that KK-42 pretreatment could promote the survival of Macrobrachium nipponense infected with Aeromonas hydrophila, which is considered to be possibly related to the prophenoloxidase (proPO), a conserved copper-containing enzyme that plays an important role in defense against pathogens. In this study, a full-length of proPO gene from M. nipponense haemocytes, designated as MnproPO, was firstly cloned and characterized. The full-length cDNA contained 2428 bp with a 2013 bp open reading frame encoding a putative proPO protein of 671 amino acids with a predicted molecular mass of 76.5 kDa and pI of 7.31. It was predicted to possess all the expected features of proPO members, including two putative copper-binding sites with six histidine residues and a thiol ester-like motif. Sequence analysis showed that MnproPO exhibited the highest amino acid sequence similarity (93%) to a proPO of Macrobrachium rosenbergii. The gene was expressed highly in haemocytes and weakly in hepatopancreas. Real-time PCR analysis revealed that the MnproPO expression increased significantly at 3, 12 and 24 h after KK-42 treatment, the PO activity also importantly rose from 6 to 48 h in KK-42-treated prawns and reached the maximum at 24 h with a 2.3-fold higher than that in control group. Injection of A. hydrophila could stimulate the MnproPO transcription and PO activity whether or not the prawns were pretreated by KK-42, the mRNA level increased obviously only at 3 h and 6 h after the bacterium injection (challenged control), but increased constantly during the phase of experiment except at 6 h under the condition of KK-42 pretreatment (challenged treatment group). The change trend of PO activity was basically similar to that of MnproPO expression. Our present results demonstrate that the MnproPO expression as well as PO activity may be induced by KK-42, which is likely one of the molecular mechanisms of KK-42 acts for increasing survival of the prawn infected with A. hydrophila.


Asunto(s)
Proteínas de Artrópodos/genética , Catecol Oxidasa/genética , Precursores Enzimáticos/genética , Imidazoles/farmacología , Palaemonidae/genética , Palaemonidae/microbiología , Vibrio/inmunología , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos/química , Proteínas de Artrópodos/metabolismo , Secuencia de Bases , Catecol Oxidasa/química , Catecol Oxidasa/metabolismo , Clonación Molecular , ADN Complementario/genética , Precursores Enzimáticos/química , Precursores Enzimáticos/metabolismo , Regulación de la Expresión Génica , Datos de Secuencia Molecular , Especificidad de Órganos , ARN/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Alineación de Secuencia , Factores de Tiempo
5.
Proc Natl Acad Sci U S A ; 104(28): 11802-7, 2007 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-17606925

RESUMEN

In this study, we investigated the relationship between c-fos expression in the auditory thalamus and corticofugal activation. The contribution of neurotransmitters and related receptors, the involvement of thalamic reticular nucleus (TRN), and the role of neuronal firing patterns in this process were also examined. The principal nuclei of the medial geniculate body (MGB) showed c-fos expression when the auditory cortex (AC) was activated by direct injection of bicuculline methobromide. However, no expression was detectable with acoustic stimuli alone. This indicated that c-fos expression in the principal nuclei of the MGB was triggered by the corticofugal projection. c-fos expression could be elicited in the MGB by direct injection of glutamate. Direct administration of acetylcholine, alternatively, had no effect. Bicuculline methobromide injection in the AC also triggered synchronized oscillatory activities sequentially in the AC and MGB. Cortically induced c-fos expression in the MGB was not mediated by a pathway involving the TRN because it remained intact after a TRN lesion with kainic acid. The present results also conclude that c-fos expression is not simply associated with firing rate, but also with neuronal firing pattern. Burst firings that are synchronized with the cortical oscillations are proposed to lead to c-fos expression in the principal nuclei of the MGB.


Asunto(s)
Corteza Auditiva/fisiología , Vías Auditivas/fisiología , Proteínas Proto-Oncogénicas c-fos/biosíntesis , Proteínas Proto-Oncogénicas c-fos/genética , Núcleos Talámicos/fisiología , Tálamo/fisiología , Estimulación Acústica , Animales , Corteza Auditiva/metabolismo , Vías Auditivas/metabolismo , Cuerpos Geniculados/metabolismo , Cuerpos Geniculados/fisiología , Masculino , Ratas , Ratas Sprague-Dawley , Transmisión Sináptica/fisiología , Tálamo/metabolismo
6.
Chinese Journal of Pediatrics ; (12): 249-251, 2003.
Artículo en Chino | WPRIM | ID: wpr-345465

RESUMEN

<p><b>OBJECTIVE</b>To investigate the clinical and neurodevelopmental profiles of patients with biotinidase deficiency and to determine the efficacy of current therapy with respect to outcome.</p><p><b>METHODS</b>Six patients aged from 3 months to 14 years with biotinidase deficiency were confirmed by urinary organic acid analysis with gas chromatography/mass spectrometry (GC/MS) and biotinidase assay on dried blood spots. Biotin was supplemented individually (10-40 mg/d). Their clinical features, laboratory findings, and treatment regimen were reviewed.</p><p><b>RESULTS</b>All the 6 patients presented with some extent of neurological abnormalities and dermatological lesions. Cases 1 - 3 had poor feeding, vomiting, seizures, mental retardation, and lethargy onset from their early infancy, with varied degree of anemia, ketosis, acidosis, and hypoglycemia. Case 2 exhibited eczema and dermatitis from his age of 7 months. Case 4 displayed motor deficit and ataxia after 6 months of age, and generalized pustular psoriasis when he was 8 months old. Cases 5 and 6 gradually showed muscle weakness and paraplegia at the age of 7 years and 5 years, respectively. Inflammatory demyelination changes of cervical cord were evident on magnetic resonance imaging in these two patients. Case 6 had progressive optic atrophy, eczema and alopecia. Remarkable elevations of urinary lactate, pyruvate, 3-OH-propionate, methylcitrate, propionylglycine, 3-OH-isovalerate, 3-methylcrontonylglycine were confirmed in cases 1, 2, 3 and 5. Slight increase of urinary lactate, pyruvate, and 3-methylcrontonylglycine was observed in cases 4 and 6. Biotinidase activities assayed on dried blood spots from all the patients were below 0.1 pmol/(min.3 mm) Biotin supplementation for all the patients, except for case 3 who was not treated, resulted in pronounced and rapid clinical and biochemical improvement. Cases 4 and 6 had residual neurological damage comprising ataxia and motor handicap of legs, due to prolonged disease course.</p><p><b>CONCLUSIONS</b>Biotinidase deficiency intensively impairs nervous system and skin in the affected patients. Urinary organic acid analysis and blood biotinidase assay are crucial to the diagnosis. Early diagnosis and biotin supplementation can contribute significantly to the improvement of prognosis.</p>


Asunto(s)
Adolescente , Niño , Preescolar , Humanos , Lactante , Masculino , Biotina , Usos Terapéuticos , Deficiencia de Biotinidasa , Diagnóstico , Quimioterapia , Orina , Cromatografía de Gases y Espectrometría de Masas , Resultado del Tratamiento
7.
Artículo en Chino | WPRIM | ID: wpr-524932

RESUMEN

Objective To investigate the causes, diagnosis and treatment of infants with secondary methylmalonic aciduria due to maternal vitamin B 12 deficiency. Methods The clinical, laboratory data and treatment of 7 children with secondary methylmalonic aciduria and their mothers′ health and nutrition were retrospectively reviewed. Results All children were presented to the hospital with vomiting, seizures or mental retardation during 1 to 13 months after birth. Varied degrees of anemia was found in 6 infants and 5 with metabolic acidosis and liver dysfunction. Methylmalonic aciduria was found in all subjects. Four of the mothers had chronic gastritis, one with gallstones in liver and gallbladder and one was a vegetarian. Decreased serum level of vitamin B 12 and folic acid and elevated homocystine concentrations were found in all mothers. After vitamin B 12 and folic acid supplementation, significant improvement was observed in all patients. Six infants showed normal development and one had mild mental retardation. Conclusions Chronic gastritis, liver/gall bladder diseases or being a vegetarian might lead to maternal vitamin B 12 deficiency and then infantile secondary methylmalonic aciduria. Early diagnosis and vitamin B 12 and folic acid supplement are crucial in improving the prognosis.

8.
Artículo en Chino | WPRIM | ID: wpr-522697

RESUMEN

Objective To investigate the clinical and laboratory profiles of a patient with pustular psoriasis-like skin lesion and cerebral palsy due to biotinidase deficiency. Methods A 5 year and 4 month-old boy with biotinidase deficiency was confirmed by urinary organic acid analysis with gas chromatography/mass spectrometry (GC/MS)and biotinidase activity assay of peripheral blood. His clinical features, laboratory findings, treatment and outcome were studied. Results The boy showed difficulty in taking food after birth, gradually eczema and pustules appeared at the age of 2 months, and generalized erythema and intractable pustular psoriasis-like lesion at the age of 8 months. His intellectual development was normal with retardation of locomotor system. He had muscular dystonia at the age of 6 months. Physical examination showed generalized pustular psoriasis-like lesion, generalized paralysis, hypertonic contracture of extremities, sparseness of scalp hair and severe malnutrition. Routine laboratory tests showed a mild anemia, metabolic acidosis and elevation of plasma creatine phosphokinase. Increased excretion of urinary lactate, pyruvate, 3-OH-propionate, propionylglycine, and 3-methylcrontonylglycine were observed. Biotinidase activity of his peripheral blood was below 0.1 pmol/min/3mm (normal 6.3-9.3 pmol/min/3mm). Biotin (10 mg/day) supplementation led to a dramatic recovery of the skin lesion. After the treatment of rehabilitation, his muscle power was also improved gradually. Conclusions Dermatological and neurological manifestations are the main features of biotinidase deficiency. Early diagnosis and biotin administration can greatly improve the clinical symptoms. Generalized pustular psoriasis-like lesion and cerebral palsy of this boy have improved after the supplementation of biotin, but he may be remained wheelchair-dependent because of delayed diagnosis.

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