CNS involvement in acute organophosphate poisoning: specific pattern of toxicity, clinical correlates and antidotal treatment

The present review was designed to integrate both experimental and clinical data and to focus on the problems of management of severe cases of acute organophosphate poisoning, which always show CNS involvement. AChE activity, in discrete regions of the human brain, was studied by quantitative histochemistry of 40 mu thick sections. The regional effects of AChE inhibition by organophosphates was examined in a comparative study of the brains of two victims and two control brains, matched for age and sex. The pattern of AChE inhibition was regionally selective. The most significant decreases were observed in the neocerebellum, thalamic nuclei and the cortex. This specific distribution of AChE inhibition may be correlated with some of the clinical characteristics of acute organophosphate poisoning. The diagnostic value of blood AChE levels was examined in a personal series of 53 patients, who needed artificial ventilation, intensive care monitoring and antidotal treatment. The effects and side-effects of the antidotal treatment were reassessed. Recommended regimen of therapy was outlined, based upon experience in this series and in recent animal studies. The logical therapy would be and almost always in the co-administration of an anticholinergic drug (usually atropine) and an AChE reactivator (oximes) in order to rapidly obtain the most beneficial effect in the critically ill patient. Seizures that do not respond to the specific antidotal therapy, should be treated with I.V. benzodiazepines. Artificial respiration and supportive measures are essential for patient' survival. They enable the patient to gain the necessary time for sufficient recovery of AChE activity.

An objective method for evaluation of the patulous eustachian tube by using the middle ear analyzer

Patulous eustachian tube is more common than is usually presumed. The symptoms of this condition can paradoxically simulate an obstruction of the eustachian tube. The characteristic eardrum movements synchronized with breathing can be overlooked or be absent altogether and, therefore, the diagnosis in many cases is missed. We suggest using the middle ear analyzer for diagnosis and objective evaluation of the patent eustachian tube by adjusting it as for acoustic reflex testing. Our method is more sensitive than the more common method of tympanometry. Information is supplied for the patient's evaluation before and after treatment.

Brain acetylcholinesterase after acute parathion poisoning: a comparative quantitative histochemical analysis post mortem

The postmortem distribution of acetylcholinesterase (AChE) inhibition was studied in the brains of 2 victims of lethal parathion intoxication and 2 control brains matched for age and sex. AChE activity in discrete brain regions was studied by quantitative histochemistry of 40-micron-thick sagittal or coronal cryostat sections from the 4 brains. Inhibition of human brain AChE by parathion is regionally selective. The biggest decreases (60-85%) were observed in the cerebellum, some thalamic nuclei, and the cortex. Only a moderate decrease (10-30%) was observed in the substantia nigra and basal ganglia, and no effect was seen in white matter. Detailed knowledge of the brain regions affected by parathion poisoning may explain some of the clinical manifestations of organophosphate poisoning.

Readaptation of the velopharyngeal valve following the uvulopalatopharyngoplasty operation

We have studied the mechanism of velopharyngeal valving in 27 patients undergoing uvulopalatopharyngoplasty for obstructive sleep apnea before and after surgery. The patients were assessed by peroral examination and nasendoscopy. Our observations and findings of the readaptation process of the velopharyngeal valve following the operation show us that its different closure patterns are due to a variable anatomy. A certain compensatory mechanism is possible mainly in the circular pattern and the circular pattern with Passavant's ridge and sagittal patterns. Passavant's ridge is an anatomic variant rather than a compensatory mechanism. The muscularis uvulae is important mainly in nonphonetic activities of the velopharyngeal valve. This information is important for clinical purposes in order to better correct problems associated with velopharyngeal incompetence.

Immobilization stress and direct glucocorticoid effects on rat septohippocampus

The rat septohippocampal cholinergic system to a large extent regulates the adaptive physiological and behavioral response to stress. The mesoseptal dopaminergic (DA) system, one of the converging inputs to the lateral septum, exerts a tonic inhibitory action on the septohippocampal cholinergic neurons. High concentrations of pituitary-adrenocortical hormones in plasma may activate the septohippocampal cholinergic system. We have sought to determine whether this mode of activation may be directly initiated by hormonal action on the cholinergic terminals, or indirectly induced through an alteration in the DA septal inputs. The results indicate that stress initiates rapid and transient changes in DA uptake by septal DA terminals, changes which probably contribute to the initial transient activation of the hippocampal cholinergic system. While the effects of glucocorticoids, observed in vitro, may mimic the enhanced ACh release in stress, they do not mimic the increased choline uptake. Nevertheless, high glucocorticoid concentrations may act directly on septal dopaminergic terminals to reduce their DA uptake capacity. These results imply that the septohippocampal cholinergic activity represents an integrative pathway for neuronal and hormonal signals of stress.

Brain acetylcholinesterase after parathion poisoning: a comparative quantitative histochemical analysis post-mortem

The regional distribution of AChE inhibition by parathion in the human brain was examined in a comparative study of the brains of 2 victims of lethal parathion intoxication and 2 control brains matched for age and sex. AChE activity in discrete brain regions was studied by quantitative histochemistry of 40 microns-thick sagittal or coronal cryostat sections from the 4 brains. The inhibition of human brain AChE by parathion is regionally selective. The biggest decreases were observed in the cerebellum, some thalamic nuclei and cortex. Only a moderate decrease (10-30%) was observed in the substantia nigra and basal ganglia, while no effect at all was seen in white matter regions. Detailed knowledge of the brain regions affected by parathion poisoning may explain some of the clinical manifestations of organophosphate poisoning.

Scrofula revisited

Mycobacterial cervical lymphadenitis, or scrofula, is a disease dating back thousands of years. In spite of modern treatment and public health measures, scrofula persists but is infrequently seen. Five patients with cervical tuberculous lymphadenitis as a sole presentation have been seen in our department in the last 10 years. The clinical presentation and current methods of diagnosis and treatment are described. A short historical review is given.

Study of Toynbee phenomenon by combined intranasopharyngeal and tympanometric measurements

The Toynbee maneuver, swallowing when the nose is obstructed, leads in most cases to pressure changes in one or both middle ears, resulting in a sensation of fullness. Since first described, many varying and contradictory comments have been reported in the literature concerning the type and amount of pressure changes both in the nasopharynx and in the middle ear. In our study, the pressure changes were determined by catheters placed into the nasopharynx and repeated tympanometric measurements. New information concerning the rapid pressure variations in the nasopharynx and middle ear during deglutition with an obstructed nose was obtained. Typical individual nasopharyngeal pressure change patterns were recorded, ranging from a maximal positive pressure of +450 to a negative pressure as low as -320 mm H2O.

Reduction of salivary flow with Scopoderm TTS

Scopoderm transdermal therapeutic system (TTS) is a form of application permitting programmed release of scopolamine through the skin into the bloodstream. Scopoderm TTS is indicated for prevention of nausea and vomiting associated with motion sickness. The most common side effect associated with its use is dryness of the mouth. We have been using Scopoderm TTS for reducing salivary flow in patients with sialorrhea or with difficulties in swallowing normal amounts of salivary secretions. Good results were achieved with minimal discomfort from adverse effects. We recommend the use of Scopoderm TTS in selected cases of sialorrhea and drooling, preoperatively and postoperatively in patients undergoing surgery of oral, laryngeal, and pharyngeal lesions.

Astereognosis as a presenting symptom in cervical meningioma

Three unusual cases with astereognosis caused by cervical meningioma are presented. Astereognosis of subcortical origin has been reported several times. According to these reports, the causative lesion was confined to the area extending between the lower brain stem and the fourth cervical vertebra, thus suggesting that a sensory centre for stereognosis could be confined within these well defined anatomical limits, and that therefore a lesion in this area could lead to astereognosis. It is assumed in this paper that the lesion involves the sensory system of the Nucleus Cervicalis Lateralis. Fibres from the spinothalamic tract, a specialized sensory pathway, ascend from the palms of the hands to this nucleus. From this nucleus arise fibres which decussate and reach the Ventral Posterolateral Nucleus of the thalamus. It is likely that a lesion of the nucleus itself or its related sensory tracts may cause astereognosis.

Eliminating the Toynbee phenomenon in patients with nasal packs

Nasal packing is a common procedure in otolaryngology, but is not a completely innocuous procedure. Besides aggravating mouth breathing, complete nasal obstruction results in an annoying Toynbee phenomenon. In patients with bilateral anterior nasal packing, we recorded high pressure gradients in the nasopharynx and, in consequence, in the middle ear. Patients in whom rubber tubes were inserted between the gauze layers of the anterior nasal packs suffered no such inconvenience and showed no such gradients. Our work proves the value of using these tubes for pressure equalization when nasal packs are necessary.

Serratia marcescens infected silk suture rejected by combined acupuncture, moxibustion and low-power laser therapy from the abdominal fascia

Upper abdominal pains lasting 12 years after cholecystectomy, were improved in an 82-year-old woman following the rejection of indigestable silk surgical sutures induced by combined therapy of acupuncture, moxibustion and low-power laser beam irradiation directed to an old post-cholecystectomy scar. An inflammatory reaction followed by granulation tissue mass was developed. Embedded in the granulation tissue were the above mentioned silk sutures which finally were expelled through the skin at the operation scar. A surgical procedure suggested to the patient, in case of acupuncture therapy failure, was obviously avoided. Serratia-marcescens infection of the expelled material was bacteriologically defined.

Can uvulopalatopharyngoplasty be harmful to eustachian tube function?

A study of the Eustachian tube, incorporating nasendoscopy, tympanometry and pressure swallow test was undertaken in patients undergoing uvulopalatopharyngoplasty. Marked negative middle ear pressure indicating impairment of tubal function was found during the first 7 postoperative days. In patients receiving antibiotic treatment the Eustachian tube dysfunction was significantly alleviated. This dysfunction is probably due to a postoperative infective inflammatory process in the tonsillar fossa. Antibiotic treatment is recommended for patients undergoing uvulopalatopharyngoplasty, to improve the postoperative course. Patients with middle ear abnormalities and following middle ear surgery could be high-risk candidates for this operation and should be carefully evaluated.

In vitro presynaptic modulation of cholinergic hippocampal activity by pituitary-adrenocortical hormones

In vivo studies have shown that high blood concentrations of pituitary-adrenocortical hormones can activate the hippocampal cholinergic terminals. Incubation of hippocampal synaptosomal preparations with methylprednisolone, or with ACTH at concentrations comparable to stress-induced high concentrations in plasma, did not have any significant effects on the cholinergic parameters measured under unactivated conditions. In the presence of either high K+ or of ACh, choline uptake was decreased. This decrease was not affected by methylprednisolone. However, methylprednisolone did enhance ACh release both after a previous increase (induced by K+) or a decrease (induced by ACh) of ACh release. In contrast, ACTH had no direct effects on either unactivated or K+-stimulated synaptosomes. Thus, a differential effect was exerted by methylprednisolone on the two presynaptic regulatory mechanisms: choline uptake (no change) and ACh release (increase). We suggest that the activation, observed in vivo, resulted mainly from indirect action of the hormones on the hippocampal cholinergic terminals, in view of the fact that the direct effect in vitro was partial.

Use of human amniotic membrane in otolaryngologic practice

Human amnion is a readily available allograft with low antigenicity, high antimicrobial potential, and the ability to foster epithelialization. We have used human amniotic membrane in our department for replacing nasal mucosa in Rendu-Osler-Weber disease, as tympanic membrane grafts, and for covering head and neck sites after flap necrosis. Our experience shows moderate success for management of severe epistaxis and excellent results in covering surfaces after flap necrosis. Use of amnion in eardrum perforations was unsuccessful and was discontinued. Properties of human amniotic membrane are listed and its application in the otolaryngologic practice is reviewed.

Tension headache treated by anti-inflammatory drug injected into GB 20 acupuncture point

The anti-inflammatory drug Voltaren (0-(36-dichlorophenyl)-amino acetate) is a relatively new substance in the systemic treatment of various pain inducing diseases related to the musculoskeletal elements. In order to achieve effective results, relatively high dosage, applied P.O.P.R. or I.M. should be used for prolonged periods. The acupuncture methods presented the eastern minded western physician with a detailed list of trigger points which may have abrogated certain painful symptoms when appropriately used by acupuncture maneuvers alone. In the present study the possibility of using the appropriate acupuncture point GB 20 for the injection of Voltaren, in an attempt to relieve stable and prolonged tension headaches, has been considered. Thus, acceptable and combined eastern-western treatment method, if found successful, may be evolved. GB 20 point has been selected because of its effective influence among others, on tension headaches, a highly common and most distressing syndrome poorly treated by conventional approaches in most clinics.

Stress-induced activation of the hippocampal cholinergic system and the pituitary-adrenocortical axis

The septo-hippocampal cholinergic system in rats undergoes rapid activation after acute stress. This is expressed by rapid increases both in high affinity choline uptake and newly synthesized acetylcholine release. Administration of ACTH or corticosterone at a high dose led 10 min later to changes comparable to those observed after acute stress. Choline uptake and acetylcholine release were also elevated 2 days after adrenalectomy. The effects of adrenalectomy could be attenuated by corticosterone, but not by ACTH treatment. The results demonstrate that (a) after short term stress the septo-hippocampal cholinergic system is activated secondary to activation of the pituitary-adrenocortical axis and (b) major changes in circulating corticosterone can modulate the activity of the hippocampal cholinergic synapse.

Dynamics of cholinergic synaptic mechanisms in rat hippocampus after stress

Changes in high affinity [3H]choline uptake, newly synthesized [3H]acetylcholine release and [3H]quinuclidinylbenzilate (QNB) binding were characterized in crude synaptosomal preparations from rat hippocampus immediately after different intervals of immobilization stress and at different times following chronic intermittent stress (2h once daily for 5 days). Choline uptake was increased to 125% of unhandled controls after 10 min of stress, after 2 h it returned to control levels and after chronic stress uptake was reduced to 75% of control. Acetylcholine release was enhanced after all stress intervals. Maximal muscarinic (QNB) binding capacity (Bmax) was increased to 135% of control only after chronic stress, with no change in Kd values. Following chronic stress the changes observed in cholinergic synaptic mechanisms all persist for up to 2 days. Recovery occurred only by the 7th post-stress day. We conclude: presynaptic hippocampal cholinergic terminals are rapidly activated by stressful stimuli and this is expressed by an increase in choline uptake and newly synthesized acetylcholine release; after prolonged periods of stress adaptive changes in the cholinergic terminals are expressed by a reduction in choline uptake and an elevation in the number of muscarinic binding sites; and the chronic stress-induced changes are slow to recover. The results demonstrate that the septo-hippocampal cholinergic system is an integral part of the adaptive response to stress.