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1.
World Neurosurg ; 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32251821

RESUMO

OBJECTIVE: Vasospasm after subarachnoid hemorrhage (SAH) plays a vital role in the development of delayed cerebral ischemia. Anti- vascular endothelial growth factor (VEGF) antibodies, like bevacizumab (BEV), may attenuate VEGF-stimulated angiogenesis, reduced vascular cell proliferation, and improve vasospasm after SAH. METHODS: Thirty-two adult male New Zealand white rabbits were randomly divided into 4 groups of 8 rabbits in each group: group 1 (control); group 2 (SAH); group 3 (SAH + vehicle); and group 4 (SAH + BEV). BEV (5 mg/kg, intraperitoneally) was administered 5 minutes after the intracisternal blood injection and continued for 72 hours once per day in the same dose for group 4. Animals were sacrificed 72 hours after SAH. Basilar artery cross-sectional areas, arterial wall thicknesses, and hippocampal degeneration scores were evaluated in all groups. RESULTS: VEGF is associated with the narrowing of the basilar artery. Treatment with BEV statistically significantly increased the cross-sectional area of the basilar artery when compared with the SAH and the vehicle groups. Basilar artery wall thicknesses in the BEV group was statistically significant smaller than in the SAH and vehicle groups. The hippocampal degeneration scores for the BEV and control groups were similar and significantly lower than those for the SAH and vehicle groups. CONCLUSIONS: Cellular proliferation and subsequent vessel wall thickening is a reason to delay cerebral ischemia and deterioration of the neurocognitive function. Intraperitoneal administration of BEV was found to attenuate cerebral vasospasm and prevent delayed cerebral ischemia and improve neurocognitive function after SAH in rabbits.

2.
Turk Neurosurg ; 30(2): 163-170, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32152999

RESUMO

AIM: To investigate the effects of an anti-ischemic agent, mildronate, on subarachnoid hemorrhage-induced vasospasm. MATERIAL AND METHODS: Rabbits were randomly divided into four groups: control, subarachnoid hemorrhage (SAH), vehicle, and mildronate (n=8 animals per group). In the treatment group, 200 mg/kg of mildronate were intraperitoneally administered 5 minutes after the procedure and continued for 3 days as daily administrations of the same dose. At the end of the third day, the cerebrum, cerebellum, and brain stem were perfused, fixated, and removed for histopathological examination. Tissues were examined for arterial wall thickness, luminal area, and hippocampal neuronal degeneration. RESULTS: Mildronate group showed significantly increased luminal area and reduced wall thickness of the basilar artery compared with the subarachnoid hemorrhage group. In addition, the hippocampal cell degeneration score was significantly lower in the mildronate group than in the SAH and vehicle groups. CONCLUSION: These results show that mildronate exerts protective effects against SAH-induced vasospasm and secondary neural injury.

3.
Metab Brain Dis ; 34(6): 1737-1746, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31444631

RESUMO

The neuroprotective and vasodilatory effects of cinnamaldehyde have been widely studied and documented. On the basis of these findings, we hypothesized that cinnamaldehyde exhibits therapeutic effects on subarachnoid hemorrhage-induced early brain injury and cerebral vasospasm. Thirty-two adult male New Zealand white rabbits were randomly divided into four groups of eight rabbits: control, subarachnoid hemorrhage, subarachnoid hemorrhage + vehicle, and subarachnoid hemorrhage + cinnamaldehyde. An intraperitoneal dose of 50 mg/kg cinnamaldehyde was administered 5 min following an intracisternal blood injection, followed by three further daily injections at identical doses. The animals were sacrificed 72 h after subarachnoid hemorrhage was induced. The cross-sectional areas and arterial wall thicknesses of the basilar artery were measured and hippocampal degeneration scores were evaluated. Treatment with cinnamaldehyde was effective in providing neuroprotection and attenuating cerebral vasospasm after subarachnoid hemorrhage in rabbits. It effectively increased the cross-sectional areas of the basilar artery and reduced the arterial wall thickness; in addition, hippocampal degeneration scores were lower in the cinnamaldehyde group. The findings of this study showed, for the first time to our knowledge, that cinnamaldehyde exhibits neuroprotective activity against subarachnoid hemorrhage-induced early brain injury and that it can prevent vasospasm. Potential mechanisms underlying the neuroprotection and vasodilation were discussed. Cinnamaldehyde could play a role in subarachnoid hemorrhage treatment.

4.
Asian J Neurosurg ; 14(1): 148-153, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30937026

RESUMO

Context: Internal rigid fixation provides immediate stability of the occipito-cervical (OC) junction for treatment of instability; however, in current practice, the optimal OC junction stabilization method is debatable. Aims: The aim of this study to test the safety and efficacy of a newly designed modified inside-outside occipito-cervical (MIOOC) plate system for the treatment of instability. Settings and Design: This was a feasibility study of MIOCC plate system. Subjects and Methods: Five male and four female patients with OC instability were treated using MIOOC plate system. Stabilization rate, safety, and efficacy were evaluated radiologically and clinically. Results: Mean age of the patients was 35 ± 11 (range: 22-58) years. Etiology of OC instability included trauma, neoplasm, congenital abnormalities, and iatrogenic. The fusion levels ranged from occiput-C3 to occiput-C6. Mean follow-up duration was 22 ± 10 (range: 6-46) months. There were neither complication nor was there any need for plate revision or screw pullout. Mortality occurred in one patient due to primary malignancy at 6 months; otherwise, no morbidity was observed. During the follow-up, no recurrent subluxation or newly developed instability at adjacent levels occurred. All patients showed a satisfactory union at the most recent follow-up examination. Conclusions: These preliminary results suggest that the MIOCC plate system is a useful and safe method for providing immediate internal stability of the OC junction. Using a multi-piece plate design in this plate system provided easy implantation and a better interface between plate and OC bones. Further, clinical studies and long-term results are needed to determine the reliability of the MIOOC plate system.

5.
Turk Neurosurg ; 29(5): 705-709, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30900735

RESUMO

AIM: To determine the relationship between the serum urate (SU) level, neutrophil / lymphocyte ratio (NLR), and pain severity using preoperative and postoperative visual analogue scale (VAS) scores in patients with lumbar disc herniation (LDH). MATERIAL AND METHODS: This single-center, cross-sectional study included 20 consecutive patients who were operated for LDH by the same surgeon. The patients'pre- and postoperative UA levels, NLRs, and intensity severity VAS scores were investigated. Preoperative magnetic resonance imaging (MRI) findings, serum UA levels, and neutrophil and lymphocyte counts were recorded. Pain severity was recorded preoperatively and at 6 months postoperatively. Effects of the preoperative SU levels and NLRs on the pre- and postoperative VAS scores were statistically assessed. RESULTS: Statistically significant positive correlation coefficients were determined between NLR and the preoperative and postoperative VAS scores. Negative correlation coefficients were found between the SU levels and preoperative VAS scores; in contrast, positive correlation coefficients were found between the SU levels and the postoperative VAS scores. CONCLUSION: Our results demonstrate the importance of not ignoring the serum UA level and NLR in pre- and postoperative pain in patients with LDH. Nevertheless, further extensive studies are warranted.


Assuntos
Degeneração do Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral/cirurgia , Linfócitos , Neutrófilos , Dor Pós-Operatória/sangue , Ácido Úrico/sangue , Adulto , Estudos Transversais , Feminino , Humanos , Degeneração do Disco Intervertebral/sangue , Degeneração do Disco Intervertebral/imunologia , Deslocamento do Disco Intervertebral/sangue , Deslocamento do Disco Intervertebral/imunologia , Vértebras Lombares/cirurgia , Contagem de Linfócitos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/imunologia , Adulto Jovem
6.
SAGE Open Med Case Rep ; 7: 2050313X19838442, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30911393

RESUMO

The Clostridium difficile infection-related disease varies from mild diarrhoea to pseudomembranouscolitis. Although C. difficile infection is commonly considered to be a hospital-acquired infection, a significant number of cases are community acquired. Community-acquired C. difficile infection can exhibit itself as ileus or toxic megacolon. Severe C. difficile infection that is unresponsive to intravenous metronidazole therapy requires more aggressive medical management and even surgical intervention. We present our case results for which vancomycin was administered both orally and intra-colonically. With this method, we treated the community acquired C. difficile infection patient who was presented as ileus.

7.
SAGE Open Med ; 7: 2050312119825784, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30719295

RESUMO

Colorectal cancer is the third most common cancer and the third leading cause of cancer-related death. The pathogensesis of colorectal cancer involves a multi-step and multi-factorial process. Disruption of the gut microbiota has been associated with gastrointestinal diseases such as colorectal cancer. The genus Bifidobacterium is considered an important component of the commensal microbiota and plays important roles in several homeostatic functions: immune, neurohormonal, and metabolic. Bifidobacterium animalis subsp. lactis is a well-documented probiotic within the species Bifidobacterium. Mycosporin-like amino acids are low molecular weight amino acids demonstrated to exert prebiotic effects and to modulate host immunity by regulating the proliferation and differentiation of intestinal epithelial cells, macrophages and lymphocytes, as well as cytokine production.Their modulation of the metabolism of the immune system and transcription factors could exert a beneficial effect on colorectal cancer. B. animalis does not produce mycosporin-like amino acids. If one could create a B. animalis-producing mycosporin-like amino acids via genetic open reading frame engineering it should exert more potent immuno-stimulatory properties and, thereby, become a potent strain-specific microbial based therapy in colorectal cancer prevention.

8.
Childs Nerv Syst ; 35(4): 593-600, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30810856

RESUMO

BACKGROUND AND AIM: Late-onset seizure due to intracerebral needle is a rare entity. Most of them were clinically asymptomatic and rarely presented with seizure. Sewing needles are used in homicidal attempt in infancy or early childhood before the closure of the fontanels. Because of sociologic, politic, and scientific deficiencies subject remained untouched. We tried shedding some light on this ambiguous phenomenon. MATERIAL AND METHODS: We report a 54-year-old man who was admitted to our neurosurgery outpatient department with epilepsy due to a sewing needle located in the left frontal lobe of the brain and made extensive literature review. RESULT: Patient's physical and neurological examinations were completely normal. All biochemical and hematological tests were normal. Cranial tomography demonstrated a linear density at the left frontal lobe compatible with a sewing needle. Patient was followed-up with antiepileptic treatment with no seizure. Sixty cases from up-to-date literature and past cases were reviewed. Patients' ages differ from 4 days to 70 years. Our review showed four cases treated with antibiotics, 19 patients went to surgery, and others just followed-up with antiepileptic and other drugs. CONCLUSION: Literature needs an autopsy series for a more intimate estimation. Due to psychosocial and legitimacy problems, matter should be handled cautiously and law enforcement agencies must be informed. Follow-up with medication is the first line of treatment with asymptomatic patients. Treatment is dictated by clinic onset, physical examination, and patient consent.

9.
World Neurosurg ; 122: e989-e994, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30399469

RESUMO

BACKGROUND: Epidural fibrosis is a major problem after spine surgery, with some patients having recurrent symptoms secondary to excessive formation of scar tissue resulting in neurologic compression. We used a rat laminectomy model to determine if topical application of boric acid could be helpful in the prevention of epidural fibrosis. METHODS: Rats were randomly assigned to 2 control and 2 experimental groups (n = 8 for each group). The negative control group received no surgery, and the positive control group underwent laminectomy only. Experimental groups were classified according to the study agents applied onto the dura mater after laminectomy at the L3 level: 2.5% boric acid solution and 5% boric acid solution. The extent of epidural fibrosis was assessed 4 weeks later macroscopically and histopathologically. RESULTS: Boric acid reduced epidural fibrosis in rats after laminectomy. The effect of 5% boric acid solution was more pronounced (P < 0.05) compared with the 2.5% solution. CONCLUSIONS: The antifibrotic effect of boric acid solution for the prevention of epidural fibrosis suggests that boric acid should be further evaluated in future studies for the prevention of epidural fibrosis.


Assuntos
Antifibrinolíticos/uso terapêutico , Ácidos Bóricos/uso terapêutico , Cicatriz/tratamento farmacológico , Espaço Epidural/efeitos dos fármacos , Animais , Antifibrinolíticos/farmacologia , Ácidos Bóricos/farmacologia , Cicatriz/etiologia , Cicatriz/patologia , Relação Dose-Resposta a Droga , Espaço Epidural/patologia , Fibrose , Laminectomia/efeitos adversos , Masculino , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/patologia , Distribuição Aleatória , Ratos , Ratos Wistar , Resultado do Tratamento
10.
Environ Sci Pollut Res Int ; 26(12): 11514-11523, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29423689

RESUMO

Heavy metal pollution in watercourses is a major environmental problem throughout the world due to rapid population growth, industrialization, and economic development. Considering this, the present study aimed to develop a new adsorbent from pumpkin husk (PH) by KOH modification to remove copper (Cu2+) ions and to explore its adsorptive potential. The sorption studies of Cu2+ on KOH-modified PH were carried out as functions of particle size, solution pH, adsorbent dose, temperature, initial metal concentration, and contact time. The sorption capacity of KOH-modified PH was found to be higher than that of raw PH, as 19.4 and 10.2 mg g-1, respectively. Morphology and surface structures of adsorbents were characterized by determination of zero point charge, a Fourier transform infrared spectrometer (FTIR-ATR) spectra, and a scanning electron microscopy (SEM) of PH powders before and after the sorption of Cu2+. The pHzpc of PH was found to be 5.0. FTIR-ATR analyses indicated that amino, amide, hydroxyl, carboxyl, and oxygenated groups of PH play an important role in the sorption process. Sorption isotherm, kinetic, and thermodynamic parameters of Cu2+ on KOH-modified PH were studied. The kinetic process was well represented by the Logistic model. The maximum sorption was found as 73.16 mg g-1 according to the well-fitting of Langmuir isotherm. Results of sorption and thermodynamic studies indicated that the process was exothermic, being feasible, and spontaneous. KOH-modified PH as an eco-friendly adsorbent had great potential to remove Cu2+ ions from aquatic system.


Assuntos
Cobre/química , Poluentes do Solo/química , Poluentes Químicos da Água/química , Adsorção , Cobre/análise , Cucurbita/química , Concentração de Íons de Hidrogênio , Hidróxidos/química , Íons , Cinética , Metais Pesados , Modelos Químicos , Tamanho da Partícula , Compostos de Potássio/química , Poluentes do Solo/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termodinâmica , Poluentes Químicos da Água/análise
11.
Arch Med Sci ; 14(6): 1459-1470, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30393502

RESUMO

Introduction: Tetracosactide is an engineered peptide that applies the same biological impacts as the endogenous adrenocorticotropic hormone. Previous studies indicated that tetracosactide has anti-inflammatory, antioxidant and neurotrophic activity. In this study, we hypothesized that tetracosactide may have protective effects in spinal cord ischemia-reperfusion injury. Material and methods: Rabbits were randomized into the accompanying four groups of eight animals each: group 1 (control), group 2 (ischemia), group 3 (methylprednisolone) and group 4 (tetracosactide). In the control group, just a laparotomy was performed. In the various groups, the spinal cord ischemia model was made by the impediment of the aorta only caudal to the renal vein. Neurological assessment was conducted with the Tarlov scoring system. Levels of myeloperoxidase, malondialdehyde and catalase were analyzed, similar to the activities of xanthine oxidase and caspase-3. Histopathological and ultrastructural assessments were additionally performed. Results: After ischemia-reperfusion injury, increments were found in the tissue myeloperoxidase levels (p < 0.001), malondialdehyde levels (p < 0.001), xanthine oxidase action (p < 0.001) and caspase-3 movement (p < 0.001). Conversely, both serum and tissue catalase levels were diminished (p < 0.001 for both). After the administration of tetracosactide, declines were seen in the tissue myeloperoxidase levels (p < 0.001), malondialdehyde levels (p = 0.003), xanthine oxidase action (p < 0.001) and caspase-3 movement (p < 0.001). Conversely, both the serum and tissue catalase levels were expanded (p < 0.001). Besides, tetracosactide treatment indicated enhanced results related to the histopathological scores (p < 0.001), the ultra-structural score (p = 0.008) and the Tarlov scores (p < 0.001). Conclusions: The findings showed for the first time that tetracosactide shows significant neuroprotective activity against ischemia-reperfusion injury of the spinal cord.

12.
World Neurosurg ; 117: e403-e410, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29913295

RESUMO

BACKGROUND: Postoperative epidural adhesion is a frequent cause of failed back surgery syndrome, manifesting with back and leg pain or neurologic deficits. Development of preventive measures for epidural adhesion after laminectomy is critical to improve outcomes of lumbar surgery. We hypothesized that positive effects of topical application of Contractubex (CTX) gel and benzothiazole (BT) individually and in combination could aid in preventing epidural fibrosis in a rat laminectomy model. METHODS: Rats were randomly assigned to 2 control and 5 experimental groups (n = 8 for each group). The control(-) group received no surgery, whereas the control(+) group underwent laminectomy without any drug administration. In experimental groups, study agents applied to dura mater after laminectomy were 100mgCTX, 2.5%BT, 5%BT; 100mgCTXplus2.5%BT, and 100mgCTXplus5%BT. Laminectomy was performed at the L3 level for all rats. The extent of epidural fibrosis was assessed 4 weeks later macroscopically and histopathologically. Hepatic and renal toxicity of study drugs was assessed histopathologically. RESULTS: Topical CTX and BT individually and in combination reduced epidural fibrosis after laminectomy in rats. Although a meaningful decrease of epidural fibrosis with individual application of CTX and BT (2.5% or 5%) was obtained (P < 0.05), the effect of their combination was more pronounced without meaningful hepatic and renal toxicity (P < 0.05). CONCLUSIONS: Combined use of topical CTX and BT could be a potential therapy for epidural fibrosis. Further research with this agents for the prevention of epidural fibrosis is warranted.


Assuntos
Alantoína/farmacologia , Benzotiazóis/farmacologia , Espaço Epidural/patologia , Heparina/farmacologia , Extratos Vegetais/farmacologia , Administração Tópica , Alantoína/administração & dosagem , Alantoína/toxicidade , Animais , Benzotiazóis/administração & dosagem , Benzotiazóis/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Modelos Animais de Doenças , Combinação de Medicamentos , Fibrose/tratamento farmacológico , Heparina/administração & dosagem , Heparina/toxicidade , Nefropatias/induzido quimicamente , Laminectomia/métodos , Masculino , Microscopia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/toxicidade , Distribuição Aleatória , Ratos Wistar
13.
Int J Neurosci ; 128(9): 828-834, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29384433

RESUMO

OBJECTIVES: A number of chemical and biological factors, including mesenchymal stem cells (MSCs), have been developed to enhance nerve regeneration by introduction through a variety of nerve conduits. This study was designed to assess the efficacy of using chitosan-coated poly-3-hydroxybutyrate (PHB) nerve conduits seeded with human bone marrow-derived MSCs (hMSC-bm) to augment repair in an experimental rat model of sciatic nerve injury. METHODS: A total of 30 rats were randomly assigned to one of three groups (n = 10). In each rat, a 10 mm segment of the sciatic nerve was removed and was replaced by a chitosan-coated PHB conduit seeded with hMSC-bm (PHB/chitosan-hMSC-bm group), a chitosan-coated PHB conduit (PHB/chitosan group), or an autograft (autograft group) as the control. The results were evaluated 8 weeks postoperatively by observation, electromyography and histologic examination with light microscopy and immunostaining. RESULTS: Histologic examination showed that both PHB/chitosan-hMSC-bm conduits and PHB/chitosan conduits led the damaged axons through the injured area. When the effects were compared, the results with the PHB/chitosan-hMSC-bm conduits were superior to those with the PHB/chitosan conduits (p < 0.05) but not as successful as with the autologous nerve grafts (p < 0.05). CONCLUSION: PHB/chitosan-hMSC-bm nerve conduits may be a useful artificial guide for nerve regeneration.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Quitosana/uso terapêutico , Hidroxibutiratos/uso terapêutico , Células-Tronco Mesenquimais/fisiologia , Regeneração Nervosa/efeitos dos fármacos , Poliésteres/uso terapêutico , Neuropatia Ciática/cirurgia , Análise de Variância , Animais , Modelos Animais de Doenças , Eletromiografia , Potencial Evocado Motor/efeitos dos fármacos , Potencial Evocado Motor/fisiologia , Masculino , Ratos , Ratos Wistar , Caminhada/fisiologia
14.
Turk Neurosurg ; 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-29131234

RESUMO

AIM: We assessed the role of triangular vertebral canal shape (VCS) in pain severity, pain-related findings, and postoperative satisfaction in patients with lumbar spinal stenosis (LSS) who had undergone decompressive surgery. MATERIAL AND METHODS: This cross-sectional study conducted at a single center included 61 consecutive patients who had undergone surgical treatment for LSS. By comparing pre- and postoperative data, the role of triangular VCS in pain severity [assessed using a visual analog scale (VAS)], pain-related findings, and postoperative satisfaction of patients was examined. VCS was determined to be triangular, oval, or circular based on magnetic resonance imaging (MRI) and magnetic resonance myelography (MRM) findings. RESULTS: Preoperative VAS scores of patients with triangular VCS were significantly higher than those of patients with oval and circular VCSs (P 0.05). No significant difference was found in postoperative VAS scores among patients with triangular, oval, and circular VCSs. In all subgroups, postoperative VAS scores were significantly lower than preoperative scores (P 0.05). This postoperative decrease in VAS scores was significantly higher among patients with triangular VCS than in those with oval or circular VCS (P 0.05). CONCLUSION: Combined use of MRI and MRM can be recommended for symptomatic patients when planning surgery. Although pain severity decreased postoperatively in all patients, this decrease was more pronounced in patients with triangular VCS than in those with oval or circular VCS. During preoperative counseling of patients with LSS, the presence of triangular VCS should be considered. This may improve surgical outcome and patient satisfaction.

15.
Food Chem ; 230: 295-305, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28407914

RESUMO

Sour cherries were dried by convectional (CD) at 50, 60, and 70°C and by hybrid (HD; microwave-convectional) drying at 120, 150, and 180W coupled with hot air at 50, 60, and 70°C. In HD, microwave power and hot air were performed simultaneously during drying process. Total phenolic content (TPC), antioxidant capacity (AOC), vitamin C content, color and rehydration capacity were followed. The HD technique reduced drying time and increased drying rate compared to CD. Drying data were well correlated with Verma and modified Logistic models which gave the best fitting for CD and HD, respectively. The modified Logistic model has never been used in food drying areas up to now. The higher TPC, AOC, vitamin C content and rehydration ability were obtained from HD. Color parameters had similar values for both drying methods. The HD technique can be accepted as an alternative drying technique for sour cherry.


Assuntos
Antioxidantes/química , Ácido Ascórbico/química , Hidratação/métodos , Micro-Ondas/uso terapêutico , Prunus avium/química , Convecção , Fenóis/análise
16.
Ecotoxicol Environ Saf ; 142: 171-180, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28411512

RESUMO

The present study prompted the second attempts to evaluate biochemical responses of filamentous algae under different physico-chemical variables in various water bodies in Turkey. These variables were investigated by use of multivariate approach in the years of 2013 (May and November) and 2014 (May and October). Studied ecoregions had the different geographic position, climate, land-use, and anthropogenic activities, could strongly affect physico-chemical variables of water bodies, which caused to change or regulate in algal biomass composition due to the different response of filamentous species. Besides, biochemical responses of species changed at different sampling times and stations. Multivariate analyses indicated that temperature, heavy metals, and nutrient contents of aquatic systems were found to be major variables driving the spatial and temporal occurrence and biochemical contents of filamentous species. Total protein and pigment production by filamentous algae were high in water bodies having high nutrients, whereas they were low in high heavy metal contents. Amount of malondialdehyde (MDA), H2O2, total thiol group, total phenolic compounds, proline, total carbohydrate, and bioaccumulation of metals by filamentous algae were closely related with heavy metal contents of water bodies, indicated by the multivariate approach. Significant increase in aforementioned biochemical compounds with a distinct range of habitats and sensitive-tolerance to environmental conditions could make them highly valuable indicators.


Assuntos
Clorófitas/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Água Doce/análise , Metais Pesados/análise , Spirogyra/crescimento & desenvolvimento , Poluentes Químicos da Água/análise , Biomassa , Ecossistema , Água Doce/química , Metais Pesados/metabolismo , Estações do Ano , Turquia , Poluentes Químicos da Água/metabolismo
17.
Ecotoxicol Environ Saf ; 133: 403-12, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27508982

RESUMO

To the best of our knowledge, any study about biochemical response of filamentous algae in the complex freshwater ecosystems has not been found in the literature. This study was designed to explore biochemical response of filamentous algae in different water bodies from May 2013 to October 2014, using multivariate approach in the South East of Turkey. Environmental variables were measured in situ: water temperature, oxygen concentration, saturation, conductivity, salinity, pH, redox potential, and total dissolved solid. Chemical variables of aqueous samples and biochemical compounds of filamentous algae were also measured. It was found that geographic position and anthropogenic activities had strong effect on physico-chemical variables of water bodies. Variation in environmental conditions caused change in algal biomass composition due to the different response of filamentous species, also indicated by FTIR analysis. Biochemical responses not only changed from species to species, but also varied for the same species at different sampling time and sampling stations. Multivariate analyses showed that heavy metals, nutrients, and water hardness were found as the important variables governing the temporal and spatial succession and biochemical compounds. Nutrients, especially nitrate, could stimulate pigment and total protein production, whereas high metal content had adverse effects. Amount of malondialdehyde (MDA), H2O2, total thiol groups, total phenolic compounds, proline, total carbohydrate, and metal bioaccumulation by filamentous algae could be closely related with heavy metals in the ecosystems. Significant increase in MDA, H2O2, total thiol group, total phenolic compounds, and proline productions by filamentous algae and chlorosis phenomenon seemed to be an important strategy for alleviating environmental factors-induced oxidative stress as biomarkers.


Assuntos
Ecossistema , Água Doce/química , Metais Pesados/farmacologia , Nitratos/farmacologia , Alga Marinha/efeitos dos fármacos , Poluentes Químicos da Água/farmacologia , Qualidade da Água , Animais , Biomassa , Exposição Ambiental , Estresse Oxidativo , Alga Marinha/metabolismo , Turquia , Água/química
18.
J Environ Sci (China) ; 45: 49-59, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27372118

RESUMO

The biosorption of phosphorus in the form of orthophosphate (Po) from wastewater using biomass as the sorbent is of potential importance because the Po-loaded biomass could be applied in the agricultural sector as fertilizer and soil conditioner. However, biomass generally displays a very low affinity for Po sorption and therefore biomass surface modification is required. In the present study, the biomass (as model grinded leaves of Phragmites sp. were used) was pretreated with Ca(OH)2 to enhance Po biosorption capacity (qe). The results indicate that the alkaline pretreatment resulted in a modification of surface functional groups. It was concluded that the main sorption mechanisms were ligand exchange and electrostatic attraction. A series of experiments were conducted to investigate the performance of the pretreated biomass for Po uptake under various conditions. Isotherm and thermodynamic studies were also applied and analyzed. The biosorption process was best described by the pseudo-second order kinetic model and Langmuir isotherm, which gave a qmax of 12.27mgP/g at 25°C and pH7. The Ca(OH)2 treated Phragmites biomass applied in this study for Po recovery may present some potential advantages in terms of costs and environmental impact.


Assuntos
Hidróxido de Cálcio/química , Fosfatos/metabolismo , Poaceae/metabolismo , Poluentes Químicos da Água/metabolismo , Adsorção , Biodegradação Ambiental , Biomassa , Termodinâmica
19.
Appl Biochem Biotechnol ; 180(4): 728-739, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27193256

RESUMO

The study was performed to investigate the effects of using cow effluent for the cultivation of Spirulina platensis on its biomass production and cell physiology. S. platensis was cultivated in three different cow effluents (CE) used as cultivation medium during 15 days. CE was prepared using dry cow manures, and it was further modified with supplement of NaNO3 (CEN) and NaNO3 + NaCl (CENS). High nitrate value stimulated chlorophyll-a and total protein content of the cyanobacterium and also biomass production in standards medium (SM) and CEN media. Total carbohydrate content of S. platensis grown in CE media was found to be higher (p < 0.05) than that of SM. Productions of biomass and biochemical compounds by the cyanobacterium grown on the CE and SM media were evaluated by using multivariate approach. Conductivity, oxidation reduction potential (ORP), salinity, pH, and TDS played important role (p < 0.01) in the biochemical composition. As an effective explanatory factor, ORP had a significant positive correlation with H2O2, whereas negatively correlated with chlorophyll-α, biomass production, filament length, and proline. Canonical correspondence analysis proposed that biochemical compounds of S. platensis were not only affected by salinity and nutrition of media but also by pH and ORP. The present study indicated that CEN as a low cost model medium had high potential for the production of biomass by S. platensis with high protein content.


Assuntos
Biomassa , Spirulina/crescimento & desenvolvimento , Spirulina/metabolismo , Estresse Fisiológico , Águas Residuárias , Animais , Bovinos , Método de Monte Carlo , Análise Multivariada , Espectroscopia de Infravermelho com Transformada de Fourier
20.
J Neurol Sci ; 363: 253-7, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27000260

RESUMO

BACKGROUND AND AIM: Cerebral hemiatrophy (CHA) is a congenital or acquired loss of volume in one hemisphere of the brain. The MR findings of the affected hemisphere have been a subject of many studies, however, the contralateral hemisphere has not been investigated. There is, in fact, an integrity between two hemispheres of the brain through transverse connection fibers. The aim of this study is to investigate the changes in the contralateral hemisphere in CHA. MATERIALS AND METHODS: Apparent diffusion coefficient (ADC) values were measured in deep gray and white matter areas in the normal-appearing contralateral hemisphere in 23 patients with CHA, in order to get in vivo information about a possible Wallerian degeneration or microstructural changes. Results were compared with the control group. RESULTS: Normal ADC values were encountered in the contralateral hemisphere in all (100%) CHA patients. The difference between the ADC values of gray and white matter in CHA patients and the control group was not statistically significant. CONCLUSION: Normal ADC values in the contralateral hemisphere in CHA patients suggests a compensatory mechanism restricting Wallerian degeneration or diffusion alteration.


Assuntos
Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Degeneração Walleriana/diagnóstico por imagem , Adolescente , Adulto , Atrofia/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
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