Cysticercosis of the fourth ventricle. A classic presentation of an old scourge

The clinical, neuroradiological, and pathological features of cysticercosis of the fourth ventricle, which occurred in a Cambodian immigrant, are reported. Comparisons between this case and Bruns' original description of cysticercosis of the fourth ventricle are made.

Primary position upbeating nystagmus. A variety of central positional nystagmus

We report a collaborative study of 11 patients with upbeat nystagmus in the primary position of gaze. In most cases the nystagmus behaved in accordance with Alexander's Law; in 3 patients convergence enhanced the nystagmus. Lateral gaze was without effect in 7 instances. Static tilt to prone and supine positions altered the characteristics of the nystagmus in 7 patients. The effects were variable and, in one case, there was reversal of the direction of the nystagmus to downbeating. There was pathological or radiological confirmation of lesions in the pontomedullary junction (2 cases) and the pontomesencephalic junction (2 cases). The findings support previous reports that primary position upbeat nystagmus occurs predominately with intra-axial brainstem lesions. There is one report of its occurrence with an intrinsic cerebellar lesion. Modification of the amplitude of upbeat nystagmus by tilt of the head with respect to gravity in the majority of patients implies an otolith-related component in the genesis of the nystagmus.

Histologic reaction to a new microsurgical suture in rabbit reproductive tissue

A newly introduced coated polyglactin suture was compared with a polyglycolic acid suture following microsurgical repair of standard rabbit uterine incisions. The degree of inflammatory response and tissue fibrosis for each suture was scored, and the results were compared. At 30 days, an inflammatory response was noted in both groups, with a greater response noted in the polyglycolic acid group. At 90 days, the inflammatory response and tissue fibrosis at the site of repair was evident in both groups, with no significant difference between the groups. The previously reported difference between these two absorbable suture materials in their earlier formulations could not be demonstrated in rabbit reproductive tissue. If an absorbable suture is used for tubal surgery, the choice can be made on considerations other than tissue reactivity.

Differing effects of pectin, cellulose and lignin on stool pH, transit time and weight

Randomized cross-over studies were undertaken to determine the effects of daily dietary supplements of pectin (12 g/d), cellulose (15 g/d) and lignin (12 g/d) on stool characteristics of healthy volunteers. Detailed dietary records were kept throughout the study. Stool collections over 48 h were used to determine mean stool pH and weight. The single stool transit time was measured using radio-opaque markers. Pectin did not significantly alter the mean stool pH, transit time or 24 h wet weight. Cellulose lowered the mean stool pH from 6.38 to 6.12, decreased mean stool transit time by 27% and increased mean wet stool weight by 57%. Lignin lowered the mean pH from 6.34 to 6.25, decreased the stool transit time by 20% and increased stool weight by 27% but these changes were not statistically significant. These findings have shown that individual fibre components have different colonic metabolic effects and support the view that associations between dietary fibre intakes and diseases such as colorectal cancer should be evaluated with regard to the type of fibre components consumed.

Selective presynaptic cholinergic neurotoxicity following intrahippocampal AF64A injection in rats

Compound AF64A, ethylcholine mustard aziridinium ion (0.4-8 nmol) was stereotaxically administered into rat dorsal hippocampus, and neurochemical changes were determined 5 days later. AF64A treatment, over an almost 10-fold dose range, resulted in a significant (up to 70%) decline in choline acetyltransferase activity. In the same tissue samples, Na+-dependent choline transport activity was also lowered, with most decreases ranging between 10 and 50% of controls; however, there was no significant correlation (r = 0.39) between these two parameters. Acetylcholinesterase activity was not affected by AF64A treatment when assayed by either histochemical or enzymatic methods. AF64A reduced acetylcholine levels by 43%, but did not alter norepinephrine content or serotonin uptake. These results demonstrate that AF64A can induce a specific, long-term reduction of cholinergic presynaptic biochemical markers in rat hippocampus. Thus, AF64A can serve as a useful new tool to study the cholinergic system and as an important agent to help develop animal models representing disorders of central cholinergic hypofunction.

Selective inhibition of peripheral cholinergic transmission in the cat produced by AF64A

The neuropharmacologic effects of ethylcholine aziridinium ion, AF64A, were studied in cats, using various physiological techniques, to ascertain its synaptic site of action and to determine whether it may act as a cholinergic specific neurotoxin in vivo. Nictitating membrane contractions elicited by preganglionic nerve stimulation (1-16 Hz) were diminished in a dose-dependent manner after injection of AF64A into the carotid artery. Contractions due to injection of l-norepinephrine, tetramethylammonium or acetylcholine were not changed. Postganglionic action potentials from the superior cervical ganglion evoked by preganglionic stimulation were also abolished by AF64A, whereas the postganglionic firing produced by tetramethylammonium was unchanged. Neither the nictitating membrane nor ganglionic responses on the contralateral side of the animal were affected by AF64A treatment. In the same animals, twitch tension in the tongue produced by stimulation of the ipsilateral hypoglossal nerve (1-16 Hz) was gradually reduced and in most experiments completely blocked by AF64A. Repetitive stimulation of either the autonomic or somatic nerves at high frequencies (greater than 10 Hz) magnified and accelerated the onset of neurotoxic effects of AF64A. The suppression of ganglionic and neuromuscular transmission by AF64A was irreversible during the course of the experiments (12-18 hr). From these results, we can conclude that AF64A produces in the peripheral nervous system a longlasting inhibition of cholinergic transmission, without interfering with adrenergic transmission. Moreover, because AF64A did not block the postganglionic responses elicited by cholinergic nicotinic and muscarinic agonists, the inhibitory effects of AF64A must be mediated by a presynaptic action on cholinergic nerve terminals.

Definitive irradiation of T1-T4N0 larynx cancer

The use of definitive irradiation in T1-T4N0 larynx cancer was reviewed in 236 patients at Rush-Presbyterian-St. Luke's Medical Center in Chicago. Recurrence-free survival for all stages was 86% at five years. Ultimate recurrence-free survival, including successful surgical salvage, was 91% at five years. The data described herein and the literature reviewed support the recommendation for definitive radiation therapy for T1 and T2N0 larynx cancer of any site. T3 lesions may also be reasonably treated with radiation therapy initially, reserving surgery for salvage. However, more data are needed to accurately identify the T3 larynx cancer patients most suited for radiation therapy.

Bioprosthetic endocarditis due to Cryptococcus neoformans

Fungal prosthetic endocarditis continues to be a lethal complication of cardiac valve replacement. We describe a patient with culture-proved Cryptococcal endocarditis and myocarditis whose non-regurgitant xenograft aortic prosthesis was successfully replaced urgently upon the occurrence of new 1st degree A-V block in the third postoperative week. Operative intervention, including vigorous debridement of the aortic root, is effective in postoperative prosthetic fungal infections involving the myocardium. The patient described herein is now infection-free, with a non-regurgitant valve, one and one-half years following operation.

Antenatal education: does it improve the quality of labour and delivery?

Of 196 nulliparous women who delivered in a two month period, 78 percent had attended antenatal education classes. The mothers who did not attend antenatal classes consisted of significantly more Maori and Pacific Island mothers, they were younger, smoked more, had a lower socioeconomic status and fewer were married. The group who went to antenatal education classes had a significantly longer second stage in labour and required more forceps assistance during delivery compared to non-attenders. These results remained for the polynesian mothers, when they were analysed separately and the differences in age and socioeconomic status were no longer present. There was no difference in the type of pain relief required during childbirth by the attenders or non-attenders. We found no evidence that attending antenatal education classes will ensure an easy and less complicated childbirth.

Dietary intakes and stool characteristics of patients with the irritable bowel syndrome

Detailed dietary records were obtained from 30 women with the irritable bowel syndrome and 25 healthy, asymptomatic women. Stool transit times and wet stool weights were measured. Analysis of the dietary data revealed no significant difference between energy, protein, fat, carbohydrate, or total fiber intakes. Total dietary fiber intake was 17 g/day in the irritable bowel group and 18 g/day in the control group, but vegetable fiber intake was significantly lower in the patients (6.6 g/day) than the controls (8.2 g/day). Cereal and fruit fiber were comparable for both groups as were the stool transit times and wet stool weights. These results do not support the hypothesis that symptoms of the irritable bowel syndrome are directly related to total or cereal fiber depletion.

Long-term central cholinergic hypofunction induced in mice by ethylcholine aziridinium ion (AF64A) in vivo

Ethylcholine mustard aziridinium ion (AF64A), a neurotoxic choline analog, was evaluated for its interactions with the cholinergic system in mice. Parenterally administered AF64A was lethal (LD50 = 32.6 mumol/kg i.v.) and the lethality could be antagonized even at 8 LD50 doses by pretreatment with choline (714 mumol/kg i.p.) 2 min earlier. Mice that were protected by choline slowly developed neurological motor disturbances such as ataxia and hypokinesia, and lost weight. Intracerebroventricular administration of 65 nmol of AF64A was not acutely lethal, but produced similar delayed behavioral effects similar to those found after parenteral administration of AF64A. Seven days after a single injection of 65 nmol of AF64A i.c.v., there was a significant decrease in acetylcholine content in the cortex, striatum and hippocampus, but no change in choline levels. Acetylcholine content was still significantly reduced in the hippocampus at 3 weeks after this treatment. The reduction in activity of choline acetyltransferase and high-affinity choline transport paralleled the reduction in acetylcholine measured at 7 days post AF64A treatment, whereas muscarinic receptors in all three brain areas were unchanged. These combined data indicate that AF64A is a presynaptic chemical neurotoxin, capable of inducing a persistent deficiency in central cholinergic transmission.

Diabetes in Kentucky

A state diabetes commission and university diabetes program in Kentucky jointly studied the social and economic impact of diabetes mellitus and its complications on the Commonwealth. This investigation revealed that diabetes was a more serious public health problem than previously supposed. Active, diagnosed diabetes afflicts 4.4% Kentucky's population. Less severe clinical and "borderline" forms of diabetes affect an additional 2.4%. Diabetes is especially prevalent in Appalachian regions and in rural, Western Kentucky. In contrast, its prevalence in Lexington, the second-largest city, is 2.7%, similar to the current, estimated national prevalence. Diabetes is the leading cause of hospitalization by disease, and costs approximately $98,800,000 to $135,000,000. Previous estimates of these social and economic losses were lower, partly because they failed to account for the impact of diabetic complications. An average of 5.23% of all hospitalized Kentuckians have diabetes. Specific services for diabetes care, including organized patient education programs, social or psychological counseling, and preventive foot care, were offered by less than 8% of accredited Kentucky hospitals. This study demonstrates the disparity between need and available services, particularly preventive services, for diabetes care in the health care system.

The AF64a-treated mouse: possible model for central cholinergic hypofunction

A loss in the number of functional, sodium ion-dependent, high-affinity choline transport sites was observed in the cortex and hippocampus of mice given an intracerebroventricular injection of 65 nanomoles of AF64A (ethylcholine mustard aziridinium ion) 3 days earlier. Such an effect was not observed in the striatum. This effect of AF64A represents a long-term neurochemical deficit at cholinergic nerve terminals in some brain regions which can lead to a persistent deficiency in central cholinergic transmission. The AF64A-treated animal may thus be a model for certain psychiatric or neurological disorders that appear to involve central cholinergic hypofunction.

Repair of the injured spleen

Splenic laceration is the most frequent visceral injury requiring laparotomy after blunt abdominal trauma in children. Splenectomy increases the risk of overwhelming bacterial infection which could prove fatal. This paper reports four patients with splenic injury who were treated by splenic repair.

Effects of infraorbital nerve section on survival, growth, and suckling behaviors of developing rats

Previous studies on sensory control of nursing in the rat have emphasized local olfactory cues. This study examined the role of tactile sensory processes by surgical section of the infraorbital nerve in rats at 17, 12, 7, and less than 1 day of postnatal age. All sectioned rats showed anesthesia of snout, upper lip, and vibrissal pads, and severe impairment of nipple attachment for at least the first day after denervation. Seven-day-old pups failed to recover, and all died after 3-6 days of relentless weight loss. Seventeen-day-old pups showed no weight loss after denervation if already weaned to solid food, but they lost weight for 3 days, and 25% failed to recover. Behavioral observations showed that denervated pups were activated by the mother's ventrum and probed for the nipple in the appropriate area but failed to focus head sweeping or licking and mouthing on the nipple itself and did not attach even when the nipple was inserted into the intact sensory areas of the mouth. Recovery after nerve section did not appear to be due to nerve regeneration. The data show that tactile cues are not necessary for normal nursing in the rat and suggest that important tactile sensorimotor adaptations may occur during the early and late phases of nursing.

Amyloid neuropathy and tremor in Waldenström's macroglobulinemia

We report a case of Waldenström's macroglobulinemia with amyloid neuropathy and a parkinsonian syndrome. We describe the light and electron microscopic findings in a sural nerve biopsy specimen and discuss the possible pathogenic mechanisms in the production of the neuropathy. In contrast to a number of previous cases of neuropathy associated with Waldenström's macroglobulinemia, evidence of immunoglobulin deposition on nerve fibers was not found using immunofluorescent techniques.

Delayed nonfatal pulmonary edema following subarachnoid hemorrhage. Case report

✓ A case of neurogenic pulmonary edema (NPE) is reported which is unusual in that it was delayed 4 days after the initial subarachnoid hemorrhage, and occurred at a time when the patient was improving clinically. After a favorable response to therapy, it recurred 48 hours later, again without neurological deterioration. The possible mechanisms in the production of NPE are discussed.

Offset rate of action of muscarinic antagonists depends on their structural flexibility

Time course measurements of the action of muscarinic antagonists were performed in the spontaneously beating carp atrium. Several high affinity drugs, which embody the quinuclidine structure were examined. The structural flexibility of these molecules was reflected in the dissociation of the drugs from the muscarinic receptor. The dissociation of rigid drugs was very much prolonged as compared to flexible drugs of the same affinity.

Guidelines for health education in maternal and child health

Guidelines are presented for specifying objectives, identifying resources, selecting methods and evaluating the health education component for maternal and child health programmes. Examples of the application of the principles are integrated with the Guidelines. Diagnostic, planning, organizational, administrative and evaluative procedures are presented around a model of health education which emphasizes: a) the careful delineation of the health problem; b) the specification of behaviours influencing the health problem; c) setting priorities among target behaviours on the basis of their relative epidemiological importance and their changeability; and d) the identification of factors that predispose, enable and reinforce the behaviour.

Fast valve for gas injection into vacuum

A simple, fast, reliable magnetically driven gas valve for use in plasma experiments is described. The pressure rise time has been measured to be approximately 1 Torr/mus at the valve opening.

Novel electrode adaptation for N2 lasers

A novel electrode design is described and its performance is indicated.

Changes in plasma catecholamines and dopamine beta-hydroxylase after corrective surgery for coarctation of the aorta

In six patients within 12 hours of surgical correction of aortic coarctation there was a 750% increase in plasma noradrenaline concentrations accompanied by an increase in systolic and diastolic blood pressures. The magnitude of the postoperative increase in noradrenaline concentrations was related to the preoperative level of the pressure gradient across the coarctation. Six months after operation plasma noradrenaline concentrations were still significantly elevated. In nine patients who underwent other types of major surgery there was a small increase in plasma noradrenaline concentrations and a return to levels within the normal range within 24 hours. Various explanations for the rise in plasma noradrenaline concentrations are considered. In particular the possibility is raised that after surgical correction of aortic coarctation the increased levels indicate a marked increase in sympathetic nervous system activity; this may be mediated by baroreceptor mechanisms and may persist for up to six months after surgery.

The effect of ascorbic acid on infection chick-embryo ciliated tracheal organ cultures by coronavirus

Chick embryo tracheal organ cultures showed increased resistance to infection by a coronavirus after exposure to ascorbate, while chick respiratory epithelium and allantois-on-shell preparations showed no increase in resistance to infection by an influenza virus or a paramyxovirus.

A control-free ventilator alarm

An alarm for use with positive-pressure lung ventilators is described. The device gives audible warning if the pressure in the patient circuit fails either to exceed or to fall below 15 cmH2O within a period of 20 seconds or if the batteries are running low. No external controls are provided and the alarm is activated when a probe connected to the breathing circuit is inserted into the alarm. The probe whistles if incorrectly connected during intermittent positive pressure ventilation. Battery life in clinical practice is longer than 6 months.

Adult coarctation of the aorta: Anaesthesia and postoperative management

The complications following surgery for the correction of aortic coarctation are reviewed. The immediate postoperative increase in blood pressure is associated with a very high (750%) increase in plasma noradrenaline concentrations. The pre-operative management and preparation of the patient, the use of induced hypotension during surgery with careful haemodynamic control to prevent the hypoperfusion of the lower segment of the aorta, and the postoperative management with special reference to adequate control of blood pressure are discussed.

Oxygen availability during hypothermic cardiopulmonary bypass

Oxygen availability during cardiopulmonary bypass was assessed in 22 patients under hypothermic and relatively normothermic conditions. The patients were divided into two groups, 17 of whom received ACD blood and 5, CPD blood. The mean P50 for all patients fell from a preoperative value of 25.9 +/- 2.4 (SD) to 15.6 +/- 2.1 during hypothermia confirming a leftward shift of the oxyhemoglobin dissociation curve. Oxygen uptake, calculated from a-v oxygen content differences (avDO2) and flow, was significantly lower during hypothermic bypass (65 +/- 27 ml/min) than during rewarming (121 +/- 41 ml/min). The increase in oxygen affinity during hypothermia was influenced also by changes in acid base and 2,3-DPG concentrations, the changes being similar in both the ACD and CPD groups of patients. During rewarming, however, oxygen availability was increased in the CPD group presumably from significantly increased 2,3-DPG concentrations. A "functional" value of hemoglobin, based upon the effects of the shift of the oxyhemoglobin dissociation curve and, therefore, reflecting the true capacity of hemoglobin to unload oxygen at the tissue level, was calculated. During the hypothermic phase of bypass, this functional hemoglobin was only 4.2 g/100 ml blood, suggesting that, in spite of reduced metabolic demands, oxygenation reserves are minimal.

Prevention by drugs of tachyphylaxis at nicotinic receptors in the cat superior cervical ganglion in situ

A new compound, AF3 (4-ethyl-6-oxa-1-azatricyclo)4.2.2.02,7)dodecan-5-one), and its 4-phenyl analogue, AF6, embodying the structural elements of acetylcholine in a highly rigid framework, were shown to evoke nicotine-like responses in the nictitating membrane (NM) and blood pressure when applied to the superior cervical ganglion in anaesthetized cats. In this respect, their equiactive molar ratio was (nicotine : 1),20-30. However, at doses that were too low to evoke any response, AF3 appeared to potentiate the responses to nicotine or tetra-methylammonium (TMA) by preventing or abolishing tachyphylaxis to the two latter drugs, the effect being dose-dependent with AF3. DMPP which produces much less tachyphylaxis, or preganglionic nerve stimulation, was little or not potentiated in presence of AF3. It is proposed that potentiation to nicotine or TMA occurs following occupancy by AF3 of a regulatory subsite, thereby preventing further access to it by nicotine or TMA. In this respect, AF3 plays the role of a "neutral" molecule.

A study of muscarinic receptor heterogeneity with weak antagonists

A study of heterogeneity among muscarinic receptors was carried out with new rigid molecules, comprising structures in the fused quinuclidine-valerolactone, quinuclidine-cyclohexenone, quinuclidine-cyclohexanone and quinuclidine-cyclohexane derivatives. These are structurally related to the potent muscarinic agent, 3-acetoxyquinuclidine but substantially different from in it conformation. All proved to antagonize acetylcholine-like activity, but to a different extent in different systems. The equipotent molar ratio with respect to atropine (as 1) was: isolated guinea pig ileum, 10,000-1,000; salivary gland (mouse), 1,000-100; superior cervical ganglion (cat), 100-10; CNS (mouse), approximately 10. It is suggested that the rigid structure induces a three-point constrained fit in the receptor (onium group, hydrophobic moiety and carbonyl group), but that not all muscarinic receptors are capable of responding equally. In this case, receptor specificity of the drug is a direct consequence of its graded departure from the preferred conformation of acetycholine and, therefore, is necessarily associated with partial loss of potency.

Resident evaluation - is our method effective?

In an earlier paper, "Resident Evaluation--Is Your Method Effective?", it was emphasized that the objectives for the residency program in Radiology should be clearly delineated and used to judge the performance of the resident in all stages of the training program. After having had approximately three years' experience in the use of the procedures outlined in the original paper, we are recommending some changes and modifications. The purpose of the evaluation is to provide clear and detailed evidence of the performance of the resident over the period of his training program. As outlined in the previous paper, the basic principles -- learning is a very individual matter, learning depends on the motivation of the individual, and learning depends on the satisfaction in the learning task--remain unaltered. Changes have been made in the design, execution and details of evaluation. The final sucess of any training program will necessarily be measured by the degree to which the residents attain the outlined objectives of the program and the degree to which the graduates of the program are accepted into the specialty by the accrediting bodies.

A new probe for heterogeneity in muscarinic receptors: 2-methyl-spiro-(1, 3-dioxolane-4, 3')-quinuclidine

The title compound (MSDQ) is a new muscarinic agonist related to 3-acetoxyquinuclidine (3-AcQ) but also of a highly rigid structure. In view of this, it may constitute a probe for the detection of heterogeneity among muscarinic receptors. Indeed, equipotent molar ratios (EPMR) for ACh, 3-AcQ and MSDQ were as follows: guinea pig ileum, 1 : 14 : 240; vasodepressor effect in the cat, 1 : 6 : 188. But EPMR for 3-AcQ and MSDQ as stimulants of the superior cervical ganglion in the cat were 1 : 1 and for the induction of tremors in mice, 9 : 5. No such subtle differences in receptor specificity were detected when the probe used was the 2, 2-diphenyl analogue (DiPSDQ) of MSDQ which was a powerful competitive antagonist in all systems, more potent than atropine, but with a CNS/PNS activity of 1.1 compared to 26 for atropine. In view of this, the use of potent antagonists as probes for muscarinic receptor heterogeneity is questionable.

Lorazepam as a premedicant for day-case surgery: an assessment

The sedative effect of 2 mg of lorazepam was assessed in eleven patients undergoing minor "day case" surgery and the results compared with a control group of eleven patients receiving a placebo. Sedation was assessed by a scoring method and quantified in terms of change in plasma cortisol levels. The results indicate that 2 mg of oral lorazepam produces good sedation (superior to nitrazepam in terms of plasma cortisol reduction) and has a postoperative anti-emetic effect but its prolonged duration of action makes it unsuitable for patients returning home within 8 hours of premedication.