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1.
Iran J Child Neurol ; 17(1): 9-28, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36721826

RESUMO

Repetitive transcranial magnetic stimulation (rTMS), often recognized as a safe and tolerable method with promising therapeutic potential for the treatment of a variety of neurological disorders, has been extensively studied by medical engineering scientists in recent decades. Epilepsy has always been one of the vital foci in the therapeutic role of rTMS, especially its low-frequency type. However, various reports, clinical trials, and review articles published in recent years have yielded conflicting results regarding the efficacy and side effects of rTMS in patients. In this review article, reviewing studies published from January 2000 to October 2021, we examined the efficacy and side effects of rTMS with a specific look at its therapeutic applications in epilepsy. Our study indicates promising results in the clinical application of this technique for patients with epilepsy. Among other things, it has the ability to reduce interictal epileptic abnormalities, does not interfere with neuropsychological function in normal people, does not worsen cognitive function and even improves Stroop function, rarely has serious side effects such as seizures and psychotic symptoms, has low risk in children as adults, and has potential for improving suicidal ideation. Despite some limitations in this study, including the small number of studies performed and the heterogeneity among studies, this review article suggests significant rtMS potentials in improving the complications of epilepsy. Our review also showed that the reported side effects of using this technique are not very common. Therefore, we can recommend further use of this technique as a promising tool in clinical research.

2.
J Biomed Phys Eng ; 13(5): 421-432, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37868943

RESUMO

Background: Multiple sclerosis (MS) is the most common non-traumatic disabling disease. Objective: The aim of this study is to investigate the ability of radiomics features for diagnosing active plaques in patients with MS from T2 Fluid Attenuated Inversion Recovery (FLAIR) images. Material and Methods: In this experimental study, images of 82 patients with 122 MS lesions were investigated. Boruta and Relief algorithms were used for feature selection on the train data set (70%). Four different classifier algorithms, including Multi-Layer Perceptron (MLP), Gradient Boosting (GB), Decision Tree (DT), and Extreme Gradient Boosting (XGB) were used as classifiers for modeling. Finally, Performance metrics were obtained on the test data set (30%) with 1000 bootstrap and 95% confidence intervals (95% CIs). Results: A total of 107 radiomics features were extracted for each lesion, of which 7 and 8 features were selected by the Relief method and Boruta method, respectively. DT classifier had the best performance in the two feature selection algorithms. The best performance on the test data set was related to Boruta-DT with an average accuracy of 0.86, sensitivity of 1.00, specificity of 0.84, and Area Under the Curve (AUC) of 0.92 (95% CI: 0.92-0.92). Conclusion: Radiomics features have the potential for diagnosing MS active plaque by T2 FLAIR image features. Additionally, choosing the feature selection and classifier algorithms plays an important role in the diagnosis of active plaque in MS patients. The radiomics-based predictive models predict active lesions accurately and non-invasively.

3.
Heliyon ; 9(5): e15911, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37223709

RESUMO

A biosensor based on glutamate oxidase (GluOx) was developed to measure glutamate concentration. The main function of this type of biosensor is related to the structure and catalytic activity of GluOx. Since radiofrequency, as the widest spectrum of electromagnetic fields, can affect the catalytic activity and structure of GluOx, in this study, the effect of these fields on the analytical parameters of the fabricated biosensor was investigated. To build the biosensor a sol-gel solution of chitosan and native GluOx were prepared and then immobilized on the surface of the platinum electrode. Similarly, to investigate the effect of radiofrequency fields on the analytical parameters of the biosensor, instead of the native GluOx, irradiated GluOx was used to build the biosensor. To evaluate the biosensor responses, cyclic voltammetry experiments were performed and voltammograms were considered as biosensor responses. To determine the analytical parameters including detection limit, linear range, and saturation region of the responses, calibration curves were drawn for each of the biosensors. Also the long-term stability and selectivity of the fabricated biosensor were evaluated. Thereafter, the optimum pH and temperature for each of these two biosensors were examined. The results showed that radiofrequency waves harmed the detection and response of biosensors in the saturation region, while they had little effect on the linear region. Such results could be due to the effect of radiofrequency waves on the structure and function of glutamate oxidase. In general, the results indicate that when a glutamate oxidase-based biosensor is used to measure glutamate in radiofrequency fields, corrective coefficients for this type of biosensor should be considered to accurately measure glutamate concentration.

4.
Br J Radiol ; 95(1136): 20211253, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35616643

RESUMO

OBJECTIVES: To employ different automated convolutional neural network (CNN)-based transfer learning (TL) methods for both binary and multiclass classification of Alzheimer's disease (AD) using brain MRI. METHODS: Herein, we applied three popular pre-trained CNN models (ResNet101, Xception, and InceptionV3) using a fine-tuned approach of TL on 3D T1-weighted brain MRI from a subset of ADNI dataset (n = 305 subjects). To evaluate power of TL, the aforementioned networks were also trained from scratch for performance comparison. Initially, Unet network segmentedthe MRI scans into characteristic components of gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF). The proposed networks were trained and tested over the pre-processed and augmented segmented and whole images for both binary (NC/AD + progressive mild cognitive impairment (pMCI)+stable MCI (sMCI)) and 4-class (AD/pMCI/sMCI/NC) classification. Also, two independent test sets from the OASIS (n = 30) and AIBL (n = 60) datasets were used to externally assess the performance of the proposed algorithms. RESULTS: The proposed TL-based CNN models achieved better performance compared to the training CNN models from scratch. On the ADNI test set, InceptionV3-TL achieved the highest accuracy of 93.75% and AUC of 92.0% for binary classification, as well as the highest accuracy of 93.75% and AUC of 96.0% for multiclass classification of AD on the whole images. On the OASIS test set, InceptionV3-TL outperformed two other models by achieving 93.33% accuracy with 93.0% AUC in binary classification of AD on the whole images. On the AIBL test set, InceptionV3-TL also outperformed two other models in both binary and multiclass classification tasks on the whole MR images and achieved accuracy/AUC of 93.33%/95.0% and 90.0%/93.0%, respectively. The GM segment as input provided the highest performance in both binary and multiclass classification of AD, as compared to the WM and CSF segments. CONCLUSION: This study demonstrates the potential of applying deep TL approach for automated detection and classification of AD using brain MRI with high accuracy and robustness across internal and external test data, suggesting that these models can possibly be used as a supportive tool to assist clinicians in creating objective opinion and correct diagnosis. ADVANCES IN KNOWLEDGE: We used CNN-based TL approaches and the augmentation techniques to overcome the insufficient data problem. Our study provides evidence that deep TL algorithms can be used for both binary and multiclass classification of AD with high accuracy.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Córtex Cerebral , Disfunção Cognitiva/diagnóstico por imagem , Humanos , Aprendizado de Máquina , Imageamento por Ressonância Magnética/métodos
5.
Basic Clin Neurosci ; 13(1): 1-14, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36589014

RESUMO

Introduction: Today, humans live in a world surrounded by electromagnetic fields. Numerous studies have been conducted to discover the biological, physiological, and behavioral effects of electromagnetic fields on humans and animals. Given the biological similarities between monkeys and humans, The present research aimed to examine Visual Memory (VM), hormonal, genomic, and anatomic changes, in the male rhesus macaques exposed to an Extremely Low-Frequency Magnetic Field (ELF-MF). Methods: Four male rhesus macaques (Macaca mulatta) were used. For the behavioral tests, the animals should be fasting for 17 hours. For the tests such as visual memory, the animal's cooperation was necessary. Using the radiation protocol, we exposed two monkeys to a 12-Hz electromagnetic field with a magnitude of 0.7 µT (electromagnetic radiation) four hours a day for a month. Before and after the exposure, a visual memory test was conducted using a coated device (visible reward) on a movable stand. Ten milliliters of blood was obtained from the femoral artery of each monkey, and half of it was used to examine cortisol serum levels using the MyBioSource kit (made in the USA). The other half of the blood was used to extract lymphocytes for assaying expressions of Glucocorticoid Receptor (GR) genes before and after radiation using the PCR method. Anatomic studies of the amygdala were carried out based on pre- and post-radiation Magnetic Resonance Imaging (MRI). Results: Research results indicated that visual memory in male primates increased significantly after exposure to the 12-Hz frequency. Hormonal analysis at the 12-Hz frequency showed a decrease in cortisol serum levels. However, visual memory and serum cortisol levels did not change considerably in male primates in the control group. There was no considerable amygdala volumetric difference after exposure to the 12-Hz frequency. The expression of the GR genes decreased in the 12-Hz group compared to the control group. Conclusion: In short, these results indicated that ELF might benefit memory enhancement because exposure to the 12-HZ ELF can enhance visual memory. This outcome may be due to a decrease in plasma cortisol and or expression of GR genes. Moreover, direct amygdala involvement in this regard cannot be recommended. Highlights: The effects of Extremely Low-Frequency Electromagnetic Fields (ELF-EMF) of 12 Hz on monkeys were studied.The results showed a reduction in the serum cortisol levels and the expression of GR genes.The amygdala anatomical area changes were not significant in the experimental group.In the experimental group, visual memory (delay of 30- and 60-s evaluation) improved after exposure to a frequency of 12 Hz. Plain Language Summary: Extremely low-frequency electromagnetic fields are among the most important factors affecting humans. This study aimed to determine the fields of 12-Hz frequency on the visual memory changes of male monkeys. The importance of research is due to the cognitive similarity of monkeys to humans. The findings of the research can be attributed to humans. Behavioral, hormonal, genetic, and anatomical studies indicated improvement in visual memory (test monkeys versus control monkeys). This study demonstrates the effect of the 12-Hz frequency on the monkey's visual memory. Researchers can study 12-Hz frequency in other cognitive indices.

6.
J Emerg Med ; 40(3): 340-5, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20097501

RESUMO

BACKGROUND: Fireworks are the leading cause of injuries such as burns and amputations during the Persian Wednesday Eve Festival (Chaharshanbeh Soori). OBJECTIVES: This study was designed to explore the age of the high-risk population, the type of fireworks most frequently causing injury, the pattern of injury, and the frequency of permanent disabilities. METHODS: This cohort study was performed by Tehran Emergency Medical Services at different medical centers all around Tehran, Iran, in individuals referred due to firework-related injuries during 1 month surrounding the festival in the year 2007. The following information was extracted from the patients' medical records: demographic data, the type of fireworks causing injury, the pattern and severity of the injury, the pre-hospital and hospital care provided for the patient, and the patient's condition at the time of discharge. In addition, information on the severity of the remaining disability was recorded 8 months after the injury. RESULTS: There were 197 patients enrolled in the study with a mean age of 20.94 ± 11.31 years; the majority of them were male. Fuse-detonated noisemakers and homemade grenades were the most frequent causes of injury. Hand injury was reported in 39.8% of the cases. Amputation and long-term disability were found in 6 and 12 cases, respectively. None of the patients died during the study period. CONCLUSION: The fireworks used during a Chaharshanbe Soori ceremony were responsible for a considerable number of injuries to different parts of the body, and some of them led to permanent disabilities.


Assuntos
Explosões , Férias e Feriados , Ferimentos e Lesões/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Criança , Estudos de Coortes , Feminino , Incêndios , Humanos , Incidência , Escala de Gravidade do Ferimento , Irã (Geográfico)/epidemiologia , Masculino , Medição de Risco , Distribuição por Sexo , Ferimentos e Lesões/diagnóstico , Adulto Jovem
7.
Emerg Med J ; 27(6): 430-2, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20562137

RESUMO

OBJECTIVES: Pre-hospital care plays a vital role in the management of trauma patients. The present study was designed to evaluate the efficacy of the pre-hospital care performed by the Tehran Emergency Medical Service (EMS) in trauma patients. METHODS: The prospective study was performed on trauma patients referred to the emergency department of a teaching hospital by the Tehran EMS from September 2004 until 2005. Considering the lack of scientific observation-based protocols on pre-hospital care, certain protocols were developed based on the available up-to-date protocols in the emergency medicine text books and were used as the gold standard for comparing the provided care by EMSs. RESULTS: The effectiveness of pre-hospital care performed by Tehran emergency technicians, compatible with the patients' condition, was evaluated in 994 patients. Wound bandaging and haemostasis were done correctly in 80% of the indicated cases. Splint was applied correctly in 50% of patients in need for such a device, whereas collar and spinal bed were not performed in 80% of the indicated cases. CONCLUSIONS: Tehran's EMS is not capable of providing trauma patients with effective and accurate pre-hospital care, indicating that major changes are needed to improve this.


Assuntos
Serviços Médicos de Emergência/métodos , Ferimentos e Lesões/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Serviços Médicos de Emergência/normas , Feminino , Humanos , Lactente , Infusões Intravenosas , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
8.
J Cancer Res Clin Oncol ; 145(9): 2199-2209, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31309302

RESUMO

PURPOSE: Radiofrequency (RF) ablation therapy is of great interest in cancer therapy as it is non-ionizing radiation and can effectively penetrate into the tissue. However, the current RF ablation technique is invasive that requires RF probe insertion into the tissue and generates a non-specific heating. Recently, RF-responsive nanomaterials such as gold nanoparticles (AuNPs) and iron oxide nanoparticles (IONPs) have led to tremendous progress in this area. They have been found to be able to absorb the RF field and induce a localized heating within the target, thereby affording a non-invasive and tumor-specific RF ablation strategy. In the present study, for the first time, we used a hybrid core-shell nanostructure comprising IONPs as the core and AuNPs as the shell (IO@Au) for targeted RF ablation therapy. Due to the magnetic core, the nanohybrid can be directed toward the tumor through a magnet. Moreover, IONPs enable the nanohybrid to be used as a magnetic resonance imaging (MRI) contrast agent. RESULTS: In vitro cytotoxicity experiment showed that the combination of IO@Au and 13.56-MHz RF field significantly reduced the viability of cancer cells. Next, during an in vivo experiment, we demonstrated that magnetically targeting of IO@Au to the tumor and subsequent RF exposure dramatically suppressed the tumor growth. CONCLUSION: Therefore, the integration of targeting, imaging, and therapeutic performances into IO@Au nanohybrid could afford the promise to improve the effectiveness of RF ablation therapy.


Assuntos
Ablação por Cateter/métodos , Compostos Férricos/química , Ouro/química , Hipertermia Induzida/métodos , Nanopartículas de Magnetita/uso terapêutico , Neoplasias/cirurgia , Ablação por Radiofrequência/métodos , Animais , Compostos Férricos/uso terapêutico , Ouro/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita/química , Masculino , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Terapia de Alvo Molecular/métodos , Nanocompostos/química , Nanocompostos/uso terapêutico , Nanoconchas/química , Nanoconchas/uso terapêutico , Neoplasias/patologia , Células Tumorais Cultivadas
9.
Surg Case Rep ; 5(1): 92, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31172312

RESUMO

BACKGROUND: Traumatic diaphragmatic injury is known to present with the spectrum of symptoms, and most patients would have some symptoms due to abdominal organ herniation. Majority of injuries tend to present on the left hemidiaphragm but right-sided injuries also occur mostly with subtle, delayed presentation due to the buffering effect of the liver. CASE PRESENTATION: A 65-year-old male presented to the emergency department with a complaint of nausea and vomiting and reported no bowel movement or passing of flatus for 5 days. Upon further questioning, he recalled that he fell from a tractor while working in his farm 2 months earlier and sustained blunt trauma to his abdomen. Both chest and abdominal X-rays revealed the niveau formation of the small intestine on the right side above the liver and right hemidiaphragm. Further evaluation with CT scan confirmed the presence of a few small intestinal loops behind the liver and also in the chest through a rupture in the right hemidiaphragm. Exploratory laparotomy was performed. Some small intestine loops had gone behind the liver and through 4 cm rupture in the posterior aspect of the diaphragm into the chest. Displaced intestinal loops were relocated and no sign of ischemia or necrosis was observed. The patient was symptom-free within 2 days and he was discharged after 4 days. CONCLUSION: Traumatic injuries of the diaphragm are rare, yet underestimated; therefore, they need a high index of suspicion for timely diagnosis and neglected diagnosis may present with a range of symptoms such as herniation months to years later.

10.
Clin Rheumatol ; 27(3): 369-71, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18172574

RESUMO

The clinical spectrum of Buerger's disease (TAO; thromboangiitis obliterans) seems to be changing. Considering the lack of any formal studies on the epidemiology of this disease in Iran, we evaluated the data of 198 confirmed cases of TAO during the period 1996-2006. Diagnosis was based on Papa's scoring system. All patients were male and aged at the time of diagnosis 40.5 +/- 10.1 years. All patients were smokers for a duration of 22.2 +/- 11.6 years. There was a strong seasonal variation for admission with winter admissions being significantly the most common (P < 0.001). Patients, 181 (91.4%), had only lower limb involvement, 4 (2.0%) had solely upper limb disease, and 13 (6.6%) suffered from both. Sympathectomy, amputation, and bypass graft surgery were performed in 97 (49.0%; lumbar: 92, thoracic: 5), 71 (35.9%), and 28 (14.1%) patients, respectively. The present report is the second one to show seasonal variation in TAO.


Assuntos
Fumar , Tromboangiite Obliterante/epidemiologia , Adolescente , Adulto , Idoso , Estudos de Coortes , Feminino , Hospitalização/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Estações do Ano , Fatores Sexuais , Tromboangiite Obliterante/complicações
11.
Perit Dial Int ; 28(6): 622-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18981392

RESUMO

BACKGROUND: Laparoscopic techniques for placement of peritoneal dialysis catheters are becoming increasingly popular. In this paper, we report the results of one-port laparoscopic placement of Tenckhoff catheters in 79 patients in our center. METHOD: Videoscopic monitoring was performed via a port inserted in the left upper quadrant and the catheter was placed via a pull-apart sheath through an incision near the umbilicus. The tip and the deep cuff of the catheter were placed into the true pelvis (on the urinary bladder) and into the rectus sheath respectively. A subcutaneous tunnel was created and a point midway on the umbilico-crestal line was selected as the exit site of the catheter. Catheters were capped for 2 weeks before initiation of peritoneal dialysis. Mean duration of the operation was 25 minutes. RESULTS: Four patients died during the follow-up period, all due to other medical problems, and 4 patients underwent renal transplantation. During a 48-month follow-up, catheter-related complications were catheter migration (1.3%; month 1), dialysate leakage (1.3%; month 1), portsite hernia (3.8%; after 6 months), exit-site infection (2.5%; months 1 and 9), and bacterial peritonitis (2.5%; after 6 months). Catheter survival was 97.2% in our series. CONCLUSION: We obtained a low complication rate and a high catheter survival rate with this one-port laparoscopic technique.


Assuntos
Cateterismo/métodos , Laparoscopia/métodos , Diálise Peritoneal/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Desenho de Equipamento , Feminino , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
J Minim Access Surg ; 4(1): 9-14, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19547671

RESUMO

This study was conducted to evaluate the safety of laparoscopic cholecystectomy (LC) during pregnancy. Patients who underwent LC were selected from several hospital databases, only six were performed during pregnancy. In this series, one of the two patients who had LC in the first trimester underwent elective termination of pregnancy while the other one gave birth to a term child normally. Half of the four who had the second trimester LC had normal deliveries at term whereas for the other two cesarean section was performed. None of our patients underwent LC in the third trimester. The findings of the present study suggest LC to be a safe procedure performed during the first and second trimester of pregnancy.

13.
Int J Health Care Qual Assur ; 20(7): 616-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18030962

RESUMO

PURPOSE: The purpose of this paper is to present a remarkable medical equipment-induced adverse event and to suggest ways to prevent similar problems. DESIGN/METHODOLOGY/APPROACH: This paper uses a case study to discuss when it is necessary to renew medical equipment. FINDINGS: The paper finds that repairing medical equipment using inappropriate parts causes severe iatrogenic problems. RESEARCH LIMITATIONS/IMPLICATIONS: Events like this may be underestimated because well-organized reporting strategies in health care units are inappropriate. PRACTICAL IMPLICATIONS: Defining expiry dates for medical equipment may prevent unsatisfactory repair, especially when original parts are unavailable. ORIGINALITY/VALUE: The paper highlights the fact that simple errors cause severe patient injuries.


Assuntos
Queimaduras por Corrente Elétrica/etiologia , Segurança de Equipamentos , Iluminação/efeitos adversos , Serviço Hospitalar de Engenharia e Manutenção/normas , Salas Cirúrgicas , Eletricidade , Análise de Falha de Equipamento , Traumatismos da Mão/etiologia , Traumatismos da Mão/cirurgia , Humanos , Doença Iatrogênica , Irã (Geográfico) , Iluminação/instrumentação , Masculino , Pessoa de Meia-Idade , Estudos de Casos Organizacionais
14.
Iran J Basic Med Sci ; 20(8): 951-957, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29085588

RESUMO

OBJECTIVES: In the present study the effect of stress on monkeys that had learned to retrieve food from a five-chamber receptacle, as well as the relationship between their behavior and the serum cortisol and epinephrine levels and relative size of the amygdala was evaluated. MATERIALS AND METHODS: Six male rhesus monkeys were individually given access to the food reward orderly. They could easily retrieve the rewards from all chambers except for the chamber 4, which a brief, mild electric shock (3 V) was delivered to them upon touching the chamber's interior. The coping behaviors were video-recorded and analyzed offline. Baseline serum cortisol and epinephrine levels were measured before the experiments using monkey enzyme-linked immunosorbent assay kit. One week after the behavioral experiment, the monkeys' brains were scanned using magnetic resonance imaging under general anesthesia. The cross-sectional area of the left amygdala in sagittal plane relative to the area of the whole brain in the same slice was evaluated by the planimetric method using ImageJ software. RESULTS: Exposure to the distressing condition caused different behavioral responses. Monkeys with higher baseline levels of serum cortisol and epinephrine and larger amygdala behaved more violently in the face of stress, indicating adopting emotion-focused stress-coping strategies. Conversely, those with low plasma epinephrine, moderate cortisol, and smaller amygdala showed perseverative behavior, indicating a problem-focused coping style. CONCLUSION: In dealing with the same stress, different responses might be observed from nonhuman primates according to their cortisol and epinephrine levels as well as their amygdala dimensions.

15.
Int J Antimicrob Agents ; 28(2): 122-7, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16815689

RESUMO

Since the bactericidal effects of beta-lactam antibiotics are time dependent, the optimum strategy for their administration could be continuous infusion. In this prospective, randomised controlled trial to evaluate the clinical efficacy of continuous infusion therapy, we evaluated the outcomes for 40 septic critically ill patients who received piperacillin either continuously (2 g intravenously (i.v.) over 0.5 h as a loading dose followed by 8 g i.v. daily over 24 h (n=20)) or as an intermittent infusion (3 g i.v. every 6h over 0.5 h (n=20)). Results from our study demonstrated that the clinical efficacy of piperacillin as a continuous infusion is superior to intermittent administration in critically ill patients. Change in APACHE II scores from baseline at the end of the second, third and fourth days, respectively, were 4.1, 5.1 and 5.2 for continuous infusion and 2.0, 2.6 and 2.8 for intermittent infusion (P< or =0.04). Considering minimum inhibitory concentrations (MICs) of 16 microg/mL and 32 microg/mL, the percentage of time for which piperacillin plasma concentrations were higher than the MIC (%T>MIC) was calculated for each patient in the two groups. For MICs of 16 microg/mL and 32 microg/mL, %T>MIC in the continuous infusion group was 100% and 65% of the dosing interval, respectively; in the intermittent infusion group, %T>MIC was only 62% and 39% of the dosing interval. There was a significant relationship between clinical results and laboratory data. It was shown that the superiority of the clinical efficacy of continuous infusion could be related to piperacillin pharmacodynamics. Continuous infusion significantly reduced the severity of illness as demonstrated by APACHE II scores during therapy.


Assuntos
Antibacterianos/administração & dosagem , Estado Terminal , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Piperacilina/administração & dosagem , Sepse/tratamento farmacológico , APACHE , Adulto , Idoso , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Esquema de Medicação , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/complicações , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Infusões Intravenosas , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Piperacilina/farmacocinética , Piperacilina/farmacologia , Piperacilina/uso terapêutico , Sepse/etiologia , Índice de Gravidade de Doença , Resultado do Tratamento
16.
Bioelectrochemistry ; 104: 79-84, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25880374

RESUMO

H2O2 generated during water radiolysis was measured electrochemically as an alternative dosimetry method. A biosensor was fabricated by immobilising modified horseradish peroxidase (HRP) on a glassy carbon electrode (GCE) followed by evaluation of its analytical parameters. Anthraquinone 2-carboxylic acid was used to modify HRP. To assess sensor performance, phosphate buffer solutions were irradiated with 0.510 Gy of gamma ray emitted from (60)Co. The results showed that this sensor can detect low quantities of hydrogen peroxide in water radiolysis. Sensitivity, detection limit and linear range of the biosensor were 260 nA/Gy, 0.392 Gy and 0.5-5 Gy, respectively. Long term stability studies showed that sensor responses were stable for at least a month. The cathodic peak current, as biosensor response, subsequently decreased to 20% of its initial value.


Assuntos
Técnicas Biossensoriais/métodos , Peroxidase do Rábano Silvestre/química , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/química , Radiometria/métodos , Água/química , Antraquinonas/química , Técnicas Biossensoriais/instrumentação , Carbono/química , Ácidos Carboxílicos/química , Eletroquímica , Eletrodos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Vidro/química , Peroxidase do Rábano Silvestre/metabolismo , Limite de Detecção , Radiometria/instrumentação
18.
J Radiat Res ; 44(3): 237-41, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14646227

RESUMO

The radioprotective effects of citrus extract were investigated by using the micronucleus test for anticlastogenic and cell proliferation activity. A single intraperitoneal (i.p.) injection of citrus extract (Citrus aurantium var. amara) at 250, 500, 1000 mg/kg body weight 1 h prior to gamma-ray irradiation (1.5 Gy) reduced the frequencies of micronucleated polychromatic erythrocytes (MnPCE(S)) and normochromatic erythrocytes (MnNCE (S)). All three doses of citrus extract significantly reduced the frequencies of MnPCEs and MnNCEs in mice bone marrow compared to non-drug-treated irradiated control (p < 0.005-0.05). The optimum dose for protection in mouse was 250 mg/kg to protect mice bone marrow 2.2-fold against the side effects of gamma-irradiation with respect to the non-drug-treated irradiated control. The flavonoids were contained in citrus extract, probably to show protective activity, and reduced the clastogenic effect of radiation on mice bone marrow. Therefore fruits and vegetables contain flavonoids to be useful as protective effects under such stress conditions as irradiation.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/efeitos da radiação , Citrus/química , Raios gama , Extratos Vegetais/farmacologia , Protetores contra Radiação/farmacologia , Animais , Células da Medula Óssea/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Divisão Celular/efeitos da radiação , Cromossomos/efeitos dos fármacos , Cromossomos/efeitos da radiação , Relação Dose-Resposta a Droga , Frutas/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes para Micronúcleos , Tolerância a Radiação/efeitos dos fármacos , Irradiação Corporal Total
20.
Biomol Ther (Seoul) ; 22(6): 570-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25489427

RESUMO

Studies have demonstrated that electromagnetic waves, as the one of the most important physical factors, may alter cognitive and non-cognitive behaviors, depending on the frequency and energy. Moreover, non-ionizing radiation of low energy waves e.g. very low frequency waves could alter this phenomenon via alterations in neurotransmitters and neurohormones. In this study, short, medium, and long-term exposure to the extremely low frequency electromagnetic field (ELF-EMF) (1 and 5 Hz radiation) on behavioral, hormonal, and metabolic changes in male Wistar rats (250 g) were studied. In addition, changes in plasma concentrations for two main stress hormones, noradrenaline and adrenocorticotropic hormone (ACTH) were evaluated. ELF-EMF exposure did not alter body weight, and food and water intake. Plasma glucose level was increased and decreased in the groups which exposed to the 5 and 1Hz wave, respectively. Plasma ACTH concentration increased in both using frequencies, whereas nor-adrenaline concentration showed overall reduction. At last, numbers of rearing, sniffing, locomotor activity was increased in group receiving 5 Hz wave over the time. In conclusions, these data showed that the effects of 1 and 5 Hz on the hormonal, metabolic and stress-like behaviors may be different. Moreover, the influence of waves on stress system is depending on time of exposure.

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