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1.
Neurochirurgie ; 68(2): 228-231, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33771616

RESUMO

BACKGROUND: Cerebral cavernous malformation (CCM) in third ventricular area may become symptomatic relatively rarely, secondary to hemorrhage and growth or rupture into the ventricle, causing obstructive hydrocephalus, during third trimester of pregnancy. CASE DESCRIPTION: A 34+4 weeks pregnant (G4P1A2) lady was admitted to one of our satellite hospitals with one-week history of severe headache, blurred vision, nausea, vomiting, and right-sided facial numbness. At presentation, she had sudden decreased level of consciousness with Glasgow Coma Scale (GCS) equal to 4, and bilateral fixed pupils. A brain computed tomography (CT) showed enlargement of both lateral ventricles with 2.5cm sized round hemorrhagic lesion at the right posterior thalamic region. After medical stabilization and placement of an external ventricular drain (EVD), the patient was referred for neurosurgical intervention. Magnetic resonance imaging (MRI) revealed a cavernous hemangioma adjacent to the right posterior wall of the third ventricle. After cesarean section and anterior interhemispheric trans-callosal approach, the mass was removed totally. However, on third postoperative day, she experienced mild hypoxia and dyspnea with fever. Chest CT-scan of the patient showed bilateral consolidation. Thereafter, COVID-19 was confirmed subsequently with positive nasopharyngeal swab testing for RT-PCR. The patient was treated as COVID-19 infection and symptoms improved on day 10 of the treatment and completely recovered. CONCLUSIONS: COVID-19 may promote ICH from CCM leading to obstructive hydrocephalous in our patient.


Assuntos
COVID-19 , Terceiro Ventrículo , Cesárea , Feminino , Humanos , Gravidez , Gestantes , SARS-CoV-2
2.
Neurochirurgie ; 66(4): 247-251, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32540343

RESUMO

BACKGROUND: Limitation of active cervical range of motion as a sequel of both spinal instrumentation and neurological injury may occur after Cervical Spinal Cord Injury (CSCI) surgery. The majority of tasks performed in daily life require a minimum of Active Cervical Range of Motion (ACROM). The aim of this study was to report ACROM in patients with subaxial CSCI, and in a control group with asymptomatic cervical spine. METHODS: A cross-sectional study was performed in 46 cases of traumatic complete motor CSCI and 41 asymptomatic cases. Patients underwent quantitative measurement of ACROM on six movements, using an analogue inclinometer, and rehabilitation status assessment on the Spinal Cord Independence Measure (SCIM) III. RESULTS: Forty-six CSCI cases and 41 asymptomatic controls were included. Mean flexion, extension, rotation, and lateral inclination were significantly lower in the CSCI group than in controls (P<0.0001). SCIMIII self-care subscores in the CSCI group showed significant correlation with mean cervical rotation (correlation coefficient, +0.508, P=0.0003). Regression analysis on mean ACROM in the CSCI group, yielded significant a negative correlation with age (P=0.037). CONCLUSIONS: CSCI significantly affected ACROM. Also, restriction of cervical rotation had significant negative correlation with SCIM-III self-care subscores.


Assuntos
Medula Cervical/lesões , Vértebras Cervicais/lesões , Traumatismos da Medula Espinal/reabilitação , Atividades Cotidianas , Adulto , Fatores Etários , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rotação , Autocuidado , Resultado do Tratamento
4.
Sci Rep ; 6: 30188, 2016 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-27457273

RESUMO

We propose an entanglement classification for symmetric quantum states based on their diagonal matrix-product-state (MPS) representation. The proposed classification, which preserves the stochastic local operation assisted with classical communication (SLOCC) criterion, relates entanglement families to the interaction length of Hamiltonians. In this manner, we establish a connection between entanglement classification and condensed matter models from a quantum information perspective. Moreover, we introduce a scalable nesting property for the proposed entanglement classification, in which the families for N parties carry over to the N + 1 case. Finally, using techniques from algebraic geometry, we prove that the minimal nontrivial interaction length n for any symmetric state is bounded by .

5.
Spinal Cord ; 54(10): 901-907, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26882485

RESUMO

STUDY DESIGN: A cross-sectional study. OBJECTIVES: This study was performed for epidemiological assessment of Iranian Traumatic Spinal Cord Injuries (TSCI), referred to a specialized spine center. SETTING: Patient recruitment and evaluations were conducted at the Brain and Spinal Injury Research Center, Tehran, Iran. METHODS: This study was performed from September 2011 to March 2015 on 1137 consecutive TSCIs. History, clinicoradiological findings as well as chronic complications and social integration were recorded. The capture-recapture method was used to calculate a rough estimation of TSCI prevalence in Tehran Province. RESULTS: Our report includes 1137 cases with a mean age of 29.1 years (s.d.=11.2 year)-79.2% of them being male (M/F=3.8/1). Rough estimation of TSCI prevalence in Tehran province was 2.36 per 10 000 population. Regarding etiology, 61.8% were due to motor vehicle accident (MVA), followed by falling 24.5%, heavy drop 5.2%, violence 3.8%, sport 2.8% and others causes 1.9%. Regarding injury level, 31.5% were cervical, 57.9% thoracic and 10.6% lumbar. Complete lesions were 53.5% of patients and 46.5% were incomplete. Most common neurological type was T1-S5 (American Spinal Injury Association Impairment Scale: A, B, C, 61.7%). Most common complications included urinary tract infection followed by pressure sore (grade III and IV, 37.5%), autonomic dysreflexia (37%) and neuropathic pain (31.2%). Substance abuse was observed in 8.8% of cases. Overall, ~25% in our cases were employed after TSCI. Secondary divorce was also much more frequent than normal matched controls. CONCLUSION: MVA was the most common cause for TSCI. The elderly subjects were less frequent among our patients than more developed countries. The high rate of unemployment and divorce in our cases deserves special consideration.


Assuntos
Traumatismos da Medula Espinal/epidemiologia , Acidentes de Trânsito , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Estudos Transversais , Emprego , Feminino , Humanos , Lactente , Recém-Nascido , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medula Espinal/patologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/etiologia , Adulto Jovem
6.
Spinal Cord ; 54(11): 1053-1057, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26882493

RESUMO

OBJECTIVES: To assess the role of anxiety, depressive mood and religious coping in erectile function among Iranian patients with spinal cord injury (SCI). SETTING: Brain and Spinal Cord Injury Repair Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran. METHODS: A sample of N=93 men with SCI participated in this cross-sectional study. Levels of anxiety and depressive mood were assessed using the Hospital Anxiety and Depression Scale. Religious coping strategies were measured using the 14-items Brief Coping Questionnaire. Erectile function was assessed using the International Index of Erectile Function. The joint effect of anxiety, depressive mood and religious coping strategies on erectile function was assessed by performing stepwise multiple linear regression analyses. RESULTS: The mean age of the SCI patients was 37.8 years with a mean post-injury time of 4.6 years. Multivariate regression analyses indicated that age (B=-0.27, 95% CI=-0.47 to -0.07), education (B for higher education=0.63, 95% CI=0.24 to 1.02), the American Spinal Injury Association impairment scale (B for complete impairment=-3.36, 95% CI=-3.82 to -2.89), anxiety (B=-3.56, 95% CI=-5.76 to -1.42), positive religious coping (B=0.30, 95% CI=0.03 to 0.57), negative religious coping (B=-0.56, 95% CI=-0.82 to -0.29) and the duration of injury (B=-0.25, 95% CI=-0.22 to -0.29) were all independent factors influencing erectile function in SCI patients. CONCLUSION: Overall, the results indicated that SCI patients who use positive religious coping strategies had better erectile function compared with individuals who applied negative religious coping strategies. Furthermore, higher levels of anxiety, greater impairment and longer duration of injury turned out to be risk factors for erectile dysfunction.


Assuntos
Ansiedade/etiologia , Depressão/complicações , Disfunção Erétil/etiologia , Religião , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/psicologia , Adaptação Psicológica , Adulto , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Estatística como Assunto , Inquéritos e Questionários , Adulto Jovem
9.
Spinal Cord ; 53(12): 860-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26238316

RESUMO

STUDY DESIGN: Prospective study. OBJECTIVES: The objective of this study was to determine whether an integrated and an intensive outpatient program would result in functional improvement of spinal cord injury (SCI) patients with American Spinal Injury Association Impairment Scale (AIS) A injuries as measured by the Spinal Cord Independence Measure (SCIM III). SETTING: Patient recruitment and evaluations were conducted at the Brain and Spinal Injury Repair Research Centre (BASIR), Tehran, Iran. METHODS: Observed SCIM III scores and SCI Ability Realization Measurement Index changes were used to measure the change in 134 patients with complete SCI (AIS A), after participation in an outpatient rehabilitation program consisting of a bimonthly multidisciplinary education program, combined with a twice-weekly occupational therapy, physical therapy and home nursing as a rehabilitation package for a 6-month period. RESULTS: A significant increase in median total SCIM III scores following comparison of 'pre-treatment' scores and final 'post-treatment' scores (9.5 score, P<0.001) was found. The increase in final SCIM III scores was highest in lower cervical (8.75 scores) and thoracic cases (13.5 scores). With the exception of high cervical patients, all subgroups had a significant SCIM III score improvement. CONCLUSION: Multidisciplinary, outpatient rehabilitation programs are recommended as a safe and an effective post-injury rehabilitation for AIS A SCI patients. Such programs may complement inpatient rehabilitation and promote functional recovery. Multidisciplinary outpatient programs are effective in achieving long-term independence in SCI patients and reducing the cost of care for developing countries. This study suggests that high cervical injuries benefit more from inpatient programs.


Assuntos
Assistência Domiciliar/métodos , Terapia Ocupacional/métodos , Modalidades de Fisioterapia , Traumatismos da Medula Espinal/reabilitação , Resultado do Tratamento , Adolescente , Adulto , Distribuição de Qui-Quadrado , Doença Crônica , Avaliação da Deficiência , Feminino , Humanos , Irã (Geográfico) , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Estudos Prospectivos , Centros de Reabilitação/estatística & dados numéricos , Tomografia Computadorizada por Raios X , Adulto Jovem
10.
Spinal Cord ; 53(12): 870-4, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26123206

RESUMO

OBJECTIVES: We evaluate the level of anxiety and depression among patients with spinal cord injury (SCI) in relation with their religious coping and spiritual health. SETTING: Brain and Spinal Cord Injury Repair Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran. METHODS: A sample of patients with SCI participated in this cross-sectional study. They completed a sociodemographic questionnaire, the Hospital Anxiety and Depression Scale, the Brief Religious Coping Questionnaire and the Spiritual Well-being Scale. Then, the association between anxiety, depression and independent variables was examined. RESULTS: In all, 213 patients with SCI were studied. Of these, 64 (30%) have had anxiety and 32 (15%) have had depression. Multiple logistic regression analyses revealed that gender (odds ratio (OR) for female=3.34, 95% confidence interval (CI)=1.31-8.51, P=0.011), employment (OR for unemployed=5.71, 95% CI=1.17-27.78, P=0.031), negative religious coping (OR=1.15, 95% CI=1.04-1.28, P=0.006) and existential spiritual well-being (OR=0.93, 95% CI=0.89-0.97, P=0.003) were significant contributing factors to anxiety (Table 3), whereas negative religious coping (OR=1.21, 95% CI=1.06-1.37, P=0.004) and existential spiritual well-being (OR=0.90, 95% CI=0.84-0.96, P=0.001) were significant contributing factors to depression. CONCLUSION: The findings indicated that depression and anxiety are two psychologically important side effects after SCI. The findings also indicated that religion and spiritual well-being have a moderating role on occurrence of depression and anxiety.


Assuntos
Adaptação Psicológica/fisiologia , Ansiedade/etiologia , Depressão/etiologia , Religião , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/psicologia , Adulto , Estudos Transversais , Feminino , Humanos , Irã (Geográfico) , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
11.
Spinal Cord ; 53(8): 621-4, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25753493

RESUMO

STUDY DESIGN: A randomized, double-blind, placebo-controlled clinical trial. OBJECTIVE: To assess the effect of alpha-lipoic acid (ALA) supplementation on IL-6, hs-CRP, FBS, anthropometric indices, food intake and blood pressure in male patients with chronic spinal cord injury (SCI). SETTING: Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran. METHODS: Fifty-eight men with chronic SCI participated in the study. Participants were divided in two groups: one group received 600 mg of supplemental ALA (n=28) and the other group received placebo (n=30) for 12 weeks. At the beginning and end of the study, biochemical parameters, anthropometric indices, blood pressure and dietary intakes were measured. Dietary intake was measured using N4 software, and statistical analyses were carried out using SPSS16. RESULTS: No significant reduction was found in IL-6 (P=0.97) and hs-CRP levels (P=0.23). There was significant reduction in fasting blood sugar (P=0.001), body weight (P=0.001), BMI (P=0.001), waist circumference (P=0.001) and blood pressure (P=0.001). Dietary intake was significantly reduced, including fat (P=0.001), carbohydrate (P=0.001), protein (P=0.002) and energy intakes (P=0.001). CONCLUSION: Lipoic acid supplementation had no significant effect on the measured inflammatory markers but it reduces fasting blood sugar, anthropometric parameters, food intake and blood pressure in men with chronic SCI.


Assuntos
Doenças Cardiovasculares/dietoterapia , Doenças Cardiovasculares/etiologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/dietoterapia , Ácido Tióctico/administração & dosagem , Complexo Vitamínico B/administração & dosagem , Adulto , Antropometria , Análise Química do Sangue , Glicemia , Pressão Sanguínea/fisiologia , Índice de Massa Corporal , Método Duplo-Cego , Ingestão de Alimentos/fisiologia , Jejum/sangue , Humanos , Irã (Geográfico) , Masculino , Fatores de Risco
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2015: 3639-42, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26737081

RESUMO

Spinal fusion permanently connects two or more vertebrae in spine to improve stability, correct a deformity or reduce pain by immobilizing the vertebrae through pedicle screw fixation. Pedicle screws should be inserted very carefully to prevent possible irrecoverable damages to the spinal cord. Surgeons use CT/fluoroscopic images to find how to insert the screws safely. However, there is still human error, as determining precise trajectory in 3D space is difficult because of asymmetric structure of pedicle. In this study we attempt to propose a shape based method to help the surgeons to find the more accurate and safe path for screw insertion that minimizes the risk or invasiveness of the surgery using pre-operative CT images. We extracted two features for insertion paths from CT images, named "safety margin" and "pedicular screw fixation strength". By using weighted k-means different paths were clustered and compared with each other. Results of comparison between those paths obtained from surgeon's pre-operative planning, intra operative and the proposed method proves a great improvement on the rate of success in reaching a suitable insertion trajectory by using our method. It is observed that the risk of damage in intra operative stage can be potentially high and it can be reduced considerably by using the proposed planning approach.


Assuntos
Vértebras Lombares , Parafusos Pediculares , Fusão Vertebral , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Fusão Vertebral/instrumentação , Fusão Vertebral/métodos
13.
Spinal Cord ; 52(8): 646-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24937696

RESUMO

OBJECTIVES: We assess the prevalence of sexual dysfunction in patients with spinal cord injury (SCI), compare sexual function and sexual distress between female patients with SCI and gender-matched healthy controls, and address risk factors associated with sexual dysfunction among Iranian female patients with SCI. SETTING: Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran. METHODS: Eligible Iranian female patients with SCI were included in this cross-sectional study. They were asked to provide sociodemographic information, and complete the Female Sexual Function Index, Hospital Anxiety and Depression Scale and Female Sexual Distress Scale-Revised questionnaire. RESULTS: Of the 105 patients participated in this study, the average age was 41.0 (s.d.=10.1) years. Women with SCI reported significantly higher levels of sexual dysfunction compared with normal controls. Approximately, 88% of SCI patients reported at least one type of sexual dysfunction, whereas only 37% of healthy controls reported sexual dysfunction. Lack of vaginal lubrication was reported more frequent in SCI patients compared with controls. Women with SCI reported a significantly higher level of sexual distress compared with healthy women. Sexual dysfunction was observed to be significantly higher in older patients, those with less education, patients with complete lesions, those with sexual distress and patients who were anxious and depressed. CONCLUSION: Sexual dysfunction is highly prevalent among Iranian women with SCI. Sexual dysfunction is associated with age, education, symptoms of depression and anxiety and level of injury. Sexual counseling during the rehabilitation period may help to prevent sexual dysfunction following SCI.


Assuntos
Doenças dos Genitais Femininos , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/epidemiologia , Adulto , Feminino , Doenças dos Genitais Femininos/epidemiologia , Doenças dos Genitais Femininos/etiologia , Doenças dos Genitais Femininos/psicologia , Humanos , Irã (Geográfico)/epidemiologia , Modelos Logísticos , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença , Fatores Socioeconômicos , Estresse Psicológico/epidemiologia , Estresse Psicológico/etiologia , Inquéritos e Questionários , Adulto Jovem
14.
Int J Occup Environ Med ; 4(4): 185-94, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24141867

RESUMO

BACKGROUND: Post-traumatic stress disorder (PTSD) is an anxiety disorder that may develop following a trauma. Iranian commercial motor vehicle drivers experience many road traffic accidents during their working life; this may increase the probability for developing PTSD, which in turn may lead to increased human errors as well as decreased work efficiency. OBJECTIVE: To examine the prevalence of PTSD and its associated factors among a group of Iranian commercial motor vehicle drivers. METHODS: In a cross-sectional study, 424 drivers who referred to participate in an annually training program were selected using a simple random sampling technique. They were requested to complete the Persian version of PCL-C and a data collection sheet about their occupational and demographic features. RESULTS: 385 (90.8%) of 424 studied drivers completed the study. 265 (68.8%) of the drivers had first-grade driving license. The mean±SD on-the-job daily driving was 10.2±2.8 h. 74 of 385 (19.2%; 95% CI: 15.3%-23.2%) met the PTSD criteria. Higher age and job experience as a professional driver, and having past history or past familial history of psychiatric disorders, were independent predictors of developing PTSD. The disease was more prevalent among drivers with first-grade driving license. CONCLUSION: The prevalence of PTSD among Iranian commercial motor vehicle drivers is higher than the figures reported elsewhere. Measures to diagnose of such drivers and to ensure optimum follow-up of victims before return to professional driving should be considered.


Assuntos
Acidentes de Trabalho , Acidentes de Trânsito , Condução de Veículo , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Acidentes de Trabalho/psicologia , Acidentes de Trabalho/estatística & dados numéricos , Acidentes de Trânsito/psicologia , Acidentes de Trânsito/estatística & dados numéricos , Adulto , Condução de Veículo/psicologia , Condução de Veículo/estatística & dados numéricos , Estudos Transversais , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Saúde Ocupacional , Prevalência
15.
East Mediterr Health J ; 16(6): 642-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20799592

RESUMO

To investigate the effects of silymarin on follicular development, we enrolled 40 healthy women undergoingin vitro fertilization (IVF) due to male factor infertility in this trial. They underwent ovulation induction and on a random and blind basis, patients were assigned to receive silymarin (70 mg x 3/day) or placebo from the beginning of the induction cycle. The number and quality of oocytes retrieved were evaluated and apoptosis of > or = granolusa cells was studied. There was no significant difference between the groups for mean number of follicles 18 mm (P = 0.131), mean number of oocytes retrieved (P = 0.209) or endometrial thickness (P = 0.673). However, the proportion of total apoptosis in the study group was significantly lower than in the placebo group (P = 0.032). These data suggest that administration of silymarin in IVF patients concomitantly with gonadotropin results in reduction of granolusa cell apoptosis but does not have any effect in promotion of follicular development, oocyte retrieval or endometrial thickness.


Assuntos
Antioxidantes/uso terapêutico , Apoptose/efeitos dos fármacos , Fertilização in vitro/métodos , Células da Granulosa/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Silimarina/uso terapêutico , Adulto , Antioxidantes/farmacologia , Gonadotropina Coriônica/uso terapêutico , Quimioterapia Combinada , Endométrio/diagnóstico por imagem , Endométrio/efeitos dos fármacos , Feminino , Humanos , Infertilidade Masculina/terapia , Irã (Geográfico)/epidemiologia , Masculino , Folículo Ovariano/diagnóstico por imagem , Folículo Ovariano/crescimento & desenvolvimento , Gravidez , Substâncias para o Controle da Reprodução/uso terapêutico , Silimarina/farmacologia , Método Simples-Cego , Resultado do Tratamento , Ultrassonografia
16.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-117932

RESUMO

To investigate the effects of silymarin on follicular development, we enrolled 40 healthy women undergoing in vitro fertilization [IVF] due to male factor infertility in this trial. They underwent ovulation induction and on a random and blind basis, patients were assigned to receive silymarin [70 mg X 3/day] or placebo from the beginning of the induction cycle. The number and quality of oocytes retrieved were evaluated and apoptosis of granolusa cells was studied. There was no significant difference between the groups for mean number of follicles >/= 18 mm [P = 0.131], mean number of oocytes retrieved [P = 0.209] or endometrial thickness [P = 0.673]. However, the proportion of total apoptosis in the study group was significantly lower than in the placebo group [P = 0.032]. These data suggest that administration of silymarin in IVF patients concomitantly with gonadotropin results in reduction of granolusa cell apoptosis but does not have any effect in promotion of follicular development, oocyte retrieval or endometrial thickness


Assuntos
Silimarina , Indução da Ovulação , Apoptose , Oócitos , Fertilização in vitro , Células da Granulosa
17.
Ann Bot ; 103(2): 221-35, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18708642

RESUMO

BACKGROUND AND AIMS: The lack of knowledge about key traits in field environments is a major constraint to germplasm improvement and crop management because waterlogging-prone environments are highly diverse and complex, and the mechanisms of tolerance to waterlogging include a large range of traits. A model is proposed that waterlogging tolerance is a product of tolerance to anaerobiosis and high microelement concentrations. This is further evaluated with the aim of prioritizing traits required for waterlogging tolerance of wheat in the field. METHODS: Waterlogging tolerance mechanisms of wheat are evaluated in a range of diverse environments through a review of past research in Australia and India; this includes selected soils and plant data, including plant growth under waterlogged and drained conditions in different environments. Measurements focus on changes in redox potential and concentrations of diverse elements in soils and plants during waterlogging. KEY RESULTS: (a) Waterlogging tolerance of wheat in one location often does not relate to another, and (b) element toxicities are often a major constraint in waterlogged environments. Important element toxicities in different soils during waterlogging include Mn, Fe, Na, Al and B. This is the first time that Al and B toxicities have been indicated for wheat in waterlogged soils in India. These results support and extend the well-known interactions of salinity/Na and waterlogging/hypoxia tolerance. CONCLUSIONS: Diverse element toxicities (or deficiencies) that are exacerbated during waterlogging are proposed as a major reason why waterlogging tolerance at one site is often not replicated at another. Recommendations for germplasm improvement for waterlogging tolerance include use of inductively coupled plasma analyses of soils and plants.


Assuntos
Adaptação Fisiológica , Elementos Químicos , Inundações , Solo , Triticum/crescimento & desenvolvimento , Triticum/fisiologia , Adaptação Fisiológica/efeitos dos fármacos , Aerobiose/efeitos dos fármacos , Alumínio/toxicidade , Anaerobiose/efeitos dos fármacos , Análise de Variância , Austrália , Biomassa , Meio Ambiente , Variação Genética , Índia , Modelos Biológicos , Oxirredução/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Triticum/efeitos dos fármacos , Triticum/genética
18.
Physiol Meas ; 28(5): 547-54, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17470987

RESUMO

The brain response to temporal frequency (TF) variation has already been reported, but with no study for different TF with respect to various spatial frequencies (SF). Functional magnetic resonance imaging (fMRI) was performed with a 1.5 Tesla General Electric system in 14 volunteers during square-wave reversal checkerboard visual stimulation with different temporal frequencies of 4, 6, 8 and 10 Hz in two states of low SF of 0.4 and high SF of 8 cpd (cycles/degree). The activation map was created using the data obtained from the block-designed fMRI study. Voxels whose Z value was above a threshold of 3.0, at a significance level P = 0.05, were considered activated. The results demonstrated that the percentage BOLD signal change in response to different TFs was the maximum value at 6 Hz for a high SF of 8 cpd, whereas it was the maximum at TF of 8 Hz for a low SF of 0.4 cpd. The results of this study agree with the results of animal invasive neurophysiological studies showing spatial and temporal frequency selectivity of neurons in visual cortical areas. These results can be useful for vision therapy (such as the treatment of amblyopia) and selecting a visual task in fMRI studies.


Assuntos
Córtex Visual/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
19.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 1032-5, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17946438

RESUMO

The brain response to temporal frequencies (TF) has been already reported, but with no study for different TFs with respect to various spatial frequencies (SF). Functional Magnetic Resonance Imaging (fMRI) experiments were performed by 1.5 Tesla General Electric-system in 14 volunteers (9 males and 5 females, range 19-26 years) during square-wave reversal checkerboard visual stimulation with different temporal frequencies of 4, 6, 8 and 10 Hz in two states of low SF of 0.5 and high SF of 8 cpd (cycles/degree). The activation map was created using the data obtained from the block designed fMRI study. Pixels whose correlation coefficient value was above a threshold of 0.33, in significant level P<0.01 were considered activated. The average percentage BOLD (blood oxygenation level dependent) signal change for all activated pixels within the occipital lobe, multiplied by the total number of activated pixels within the occipital lobe, was used as the criterion for the strength of the fMRI signal at each state of TF&SF. The results demonstrated that the strength of the fMRI signal in response to different TFs was maximum in 6Hz for high SF of 8 cpd, while it was maximum at TF of 8Hz for low SF of 0.5 cpd. The results of this study agree with the results of animal invasive neurophysiological studies showing spatial and temporal frequency selectivity of neurons in visual cortical areas. These results can be useful for vision therapy (such as the treatment of Amblyopia) and selecting visual task in fMRI studies.


Assuntos
Mapeamento Encefálico/métodos , Potenciais Evocados Visuais/fisiologia , Imageamento por Ressonância Magnética/métodos , Estimulação Luminosa/métodos , Percepção Espacial/fisiologia , Córtex Visual/fisiologia , Adaptação Fisiológica/fisiologia , Adulto , Feminino , Humanos , Masculino
20.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 5802-3, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281577

RESUMO

The brain response to temporal frequencies (TF) has been already reported, but with no study for different TF in respect to various spatial frequencies (SF). fMRI was performed by 1.5T GE-system in 14 volunteers during checkerboard visual stimulation, with TFs of 4, 6, 8 and 10Hz in low and high SFs of 0.5 and 8cpd. The averaged percentage BOLD signal changes demonstrated the amplitude of the fMRI response to different TFs which was maximally at 6Hz for high SF of 8cpd, and at 8Hz for low SF of 0.5cpd. The results are useful for vision therapy (such as the treatment of Amblyopia) and for fMRI applications incorporating visual tasks.

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