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Biomedical subjects

J Backon

Publications and source records attributed to J Backon.

At least 19 recordsLinked to original sources
PubMed1997

The anticonvulsant effect of deprenyl on pentylenetetrazol-induced seizures in Lewis rats.

There is recent evidence that deprenyl may have anticonvulsant action in a rat kindling model of epilepsy as well as in a maximal electroshock model. We therefore investigated the effect of deprenyl on the brain sensitivity threshold to pentylenetetrazol (PTZ)-induced maximal seizures in Lewis rats, in a model that provides pharmacodynamic information free of pharmacokinetic interference. The novel finding of this investigation was the anticonvulsant effect of deprenyl following repetitive administration whereas a single deprenyl dose did not affect the PTZ concentrations required to induce maximal seizures. The data suggests that the mechanism of this effect is not associated with the dopaminergic activity of deprenyl since pretreatment with both bromocriptine (a dopamine D2 agonist) and haloperidol (dopamine antagonist) did not affect the seizure threshold, whereas levodopa caused a proconvulsant effect. It was also concluded that the mechanism is not related to changes in acetylcholine levels since prolonged pretreatment with deprenyl did not attenuate the brain sensitivity to pilocarpine-induced seizures. The fact that long term administration of deprenyl was needed to produce its anticonvulsant effect may indicate that the anticonvulsant effect of deprenyl may be due to changes in levels of certain endogenous compounds or down or up-regulation of relevant receptor/effector units.

Animals↗
PubMed1994

Differential effects of various antiinflammatory drugs on theophylline neurotoxicity.

The purpose of the present investigation was to evaluate whether antiinflammatory drugs affect the pharmacodynamics of theophylline-induced seizures. Adult male Lewis rats were treated with either dexamethasone (DEX), hydrocortisone (HYD), ibuprofen (IBU), or mefenamic acid (MFA), for 4 consecutive days. On the fourth day they received a constant infusion of theophylline (2 mg/min IV) until the onset of maximal seizures. Then, blood and cerebrospinal fluid (CSF) were obtained for theophylline concentration determinations by HPLC. It was found that pretreatment with the corticosteroids DEX and HYD elevated the CSF theophylline concentration required to induce maximal seizures in comparison to the untreated rats (242 +/- 6, 232 +/- 6, and 203 +/- 10 mg/l, respectively, n = 10, p < 0.05). MFA also increased the CSF theophylline concentration at that end-point in comparison to the controls (p < 0.01), whereas pretreatment with IBU had no effect (280 +/- 10 MFA, 225 +/- 9 IBU vs. 220 +/- 8 controls, n = 12). The data suggests that concomitant treatment with antiinflammatory drugs, together with theophylline, do not increase the risk for theophylline-induced seizures. Moreover, in certain cases they may elevate the seizure threshold and protect against these hazardous episodes.

Adrenal Cortex Hormones↗
PubMed1991

Dementia in cancer patients undergoing chemotherapy: implication of free radical injury and relevance to Alzheimer disease.

A number of neurological disorders including Alzheimer and Parkinson disease have been suggested to be caused by processes leading to lipid peroxidation. Other theories implicate the accumulation of damaged DNA, resulting from a defect in DNA repair, in the pathogenesis of these disorders. I suggest that these theories might be related, since the hydroxy free radical is known to attack DNA and inactivate enzymes so that oxygen metabolism has the potential to interfere with the maintenance of genomic integrity. Since psychometric intelligence correlates highly with erythrocyte glutathione peroxidase activity, a free radical scavenger, perhaps this might explain the marked intellectual impairment caused by chemotherapeutic agents such as cytosine arabinoside, as well as in Alzheimer disease.

Alzheimer Disease↗
PubMed1991

Mechanism of analgesic effect of clonidine in the treatment of dysmenorrhea.

Clonidine substantially reduces the pain and cramping of dysmenorrhea. The mechanisms for this effect may lie in increased release of analgesic opioids. It is suggested that perhaps a thromboxane synthetase inhibitor such as ginger which activates endorphin receptors may also be an effective treatment.

Analgesics↗
PubMed1991

Implication of thromboxane in the pathogenesis of Kawasaki disease and a suggestion for using novel thromboxane synthetase inhibitors in its treatment.

Kawasaki disease, a mucocutaneous lymph node syndrome predominantly prevalent in children, presents with coronary artery aneurysms and thrombocytosis, and investigators have suggested use of anticoagulants in addition to platelet inhibiting drugs. In Kawasaki disease, hypersensitivity reactions due to antigen/antibody complexes (Arthus type III) may damage the vessel wall and induce arteritis, and antigens may be of microbial or viral origin. Since thromboxane has been implicated in the pathogenesis of Kawasaki disease, I suggest use of ginger and carbon dioxide, novel thromboxane synthetase inhibitors. Thromboxane synthetase inhibitors may act as anticoagulants, platelet inhibitors, anti-inflammatory agents, and agents with both antimicrobial and antiviral activity.

Carbon Dioxide↗
PubMed1991

A straight nasal septum and right unilateral hypertrophied inferior nasal turbinate, a very rare anatomical phenomenon, in skilled language translators: relevance to anomalous dominance, brain hemisphericity and second language acquisition.

Research on second language acquisition has recently focused on the concept of brain hemisphericity. Since the nasal cycle indexes brain hemisphericity and a deviated nasal septum itself affected by structural brain dominance may prevent nasal cycling, we investigated the presence of septal deviation and inferior turbinate hypertrophy in 11 expert translators. We found that 10 of the 11 subjects demonstrated both a straight nasal septum and right unilateral inferior turbinate hypertrophy, an extremely rare anatomical phenomenon. The one-tailed binomial test was extremely significant (p < .0000001). This anatomical phenomenon, which can be noninvasively checked in less than 30 seconds may predict excellence in second language acquisition.

Adult↗
PubMed1990

Prevalence of depression among Israeli alcoholics.

The Zung Depression Scale was given to 45 Israeli male alcoholics as diagnosed by DSM-III criteria. Eighteen subjects came from an outpatient alcohol clinic, and 27 came from an inpatient detoxification center. In this cohort, 60% of subjects were classified as having clinical depression, and major depressive disorder was found in 26% of inpatients and 17% of outpatients. Pattern analysis of the Zung showed a disproportionately high percentage of all subjects responding to clinical symptoms featured in bipolar disorder, while the inpatient group reported significantly more difficulty than the outpatient group on parameters of pervasive affective disorder, early and frequent waking, constipation, irritability, and emptiness.

Adult↗
PubMed1990

Interactions between non-symmetric mechanical vector forces in the body and the autonomic nervous system: basic requirements for any mechanical technique to engender long-term improvements in autonomic function as well as in the functional efficiency of the respiratory, cardiovascular, and brain systems.

There are known anatomical asymmetries in the respiratory, cardiovascular, and nervous system. The coupling mechanisms between each of these systems--lungs-heart, heart-brain, and lungs-brain--are also asymmetrical. There is a growing body of literature indicating that mechanical pressure asymmetrically applied to certain areas of the human body produces changes in the balance of autonomic parameters. These findings implicitly indicate that not only magnitude but also the direction and point of application of the force play a role in its influence upon the autonomic nervous system. Therefore, we suggest that asymmetrical vector forces resulting from the mechanical activity of the lungs, heart and blood moving throughout the circulatory system, will also produce a lateralization effect in autonomic balance.

Autonomic Nervous System↗
PubMed1990

Interactions between non-symmetric mechanical vector forces in the body and the autonomic nervous system: basic requirements for any mechanical technique to engender long-term improvements in autonomic function as well as in the functional efficiency of the respiratory, cardiovascular, and brain systems.

There are known anatomical asymmetries in the respiratory, cardiovascular, and nervous system. The coupling mechanisms between each of these systems--lungs-heart, heart-brain, and lungs-brain--are also asymmetrical. There is a growing body of literature indicating that mechanical pressure asymmetrically applied to certain areas of the human body produces changes in the balance of autonomic parameters. These findings implicitly indicate that not only magnitude but also the direction and point of application of the force play a role in its influence upon the autonomic nervous system. Therefore, we suggest that asymmetrical vector forces resulting from the mechanical activity of the lungs, heart and blood moving throughout the circulatory system, will also produce a lateralization effect in autonomic balance. We postulate the existence of negative feedback loops between brain autonomic control and mechanical functions in the body as a fundamental part of the body's homeostatic mechanisms. It follows that any mechanical assist to the respiratory or cardiovascular system will be significantly reduced or even eliminated if these homeostatic mechanisms are not taken into account. Our hypothesis predicts that a long-term improvement in autonomic balance as well as in respiratory, cardiovascular, and brain function can be achieved if mechanical forces are applied to the body with the aim of reducing existing imbalances of mechanical force vectors. This technique implies continually controlling for precise timings resulting from physiological periodical forces as well as factors derived from anatomical and coupling asymmetries in the respiratory, cardiovascular, and nervous systems.

Autonomic Nervous System↗
PubMed1990

A functional vagotomy induced by unilateral forced right nostril breathing decreases intraocular pressure in open and closed angle glaucoma.

There is evidence of the central regulation of intraocular pressure, and it has been suggested that vagal tone might be increased in glaucoma simplex. The nasal cycle, the simultaneous congestion-decongestion response in the nasal cavities, reflects the dynamic lateralisation of the autonomic nervous system. Since this lateralisation presents with sympathetic activity induced by left brain hemisphere stimulation and parasympathetic activity induced by right hemisphere stimulation, it was subsequently demonstrated that forced unilateral nostril breathing induces selective contralateral hemispheric stimulation as measured by relative increases in the electroencephalographic amplitude in the contralateral hemisphere as well as alternating lateralisation of plasma catecholamines. Using this functional vagotomy, we report that left hemispheric stimulation by 20 minutes of forced unilateral right nostril breathing led to a significant bilateral decrease of 4.6 mmHg (25%) in intraocular pressure in 46 patients with open and closed angle glaucoma. However, it significantly increased the IOP in three patients with neovascular, one with juvenile onset, and one with closed angle glaucoma.

Adolescent↗