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A historical review is presented of a number of aspects of early animal experiments and clinical trials dealing with the i.v. infusion of whole blood and milk; the nutritional use of i.v. erythrocytes, plasma proteins, protein hydrolysates, amino acids, and glucose; and development and use of i.v. fat emulsions. A brief description of the experience with the nutritional use of i.v. ethyl alcohol is also presented. The important studies beginning in the 1960's by Dudrick, Rhoads, Vars, and Wilmore are described elsewhere by them.

Visual cognitive differences between hearing (N = 16) and deaf (N = 32) high-school and middle-school students were studied. Visual tasks were presented on a microcomputer and response latencies were collected. Significant differences were noted between the deaf and normal groups but not between total communication deaf and oral deaf students. These differences support the hypothesis that deaf students prefer a visual cognitive strategy. Implications for educating the deaf are discussed.

We compared the effects of hypoxia and hypercapnia on pulmonary mechanics in the newborn dog. Animals were anesthetized with a mixture of chloralose/urethane, paralyzed and ventilated with the chest open. Following an inflation to control volume history, mean inspiratory resistance (RLi) and dynamic compliance (CLdyn) were measured on a breath-by-breath basis during ventilation with control (FIO2 = 0.4), hypoxic (FIO2 = 0.1) and hypercapnic (FICO2 = 0.05) gas mixtures. Hypercapnia increased RLi 63% (n = 9) while hypoxia increased RLi in only 1/9 animals. Neither gas mixture changed CLdyn compared to control. The response to hypercapnia and the lone hypoxic response were eliminated by denervation of the airways by atropine administration or vagotomy. Following airway denervation hypoxia caused a small but statistically significant fall in CLdyn compared to the denervated control. These findings demonstrate that the newborn dog is capable of reflexly increasing bronchomotor tone and that vagal efferent innervation to the airways is functional at birth. Our data also suggest that in the newborn, central chemoreceptors are more effective than peripheral chemoreceptors in altering vagal tone to airway smooth muscle. Increased bronchomotor tone with hypercapnia may help to prevent dynamic compression of the airways.

The present study was designed to investigate the effects of hypoxia on lung mechanics in the newborn cat and to determine if vagal efferent innervation to the airways is involved in the response. We studied 11 animals, aged 2-7 days, anesthetized with a mixture of chloralose-urethane administered intraperitoneally. A tracheal cannula was inserted just below the larynx and following paralysis (pancuronium bromide), mechanical ventilation was initiated. A pneumothorax was created by a midline thoracotomy and an end-expiratory load was applied to maintain functional residual capacity. Animals were placed in a flow plethysmograph from which measurements of transpulmonary pressure, flow, and volume, mean inspiratory resistance, and dynamic compliance of the lung were calculated. The experimental protocol consisted of a series of 8-min trials, each preceded by a controlled volume history. The hypoxia challenge was composed of 1 min of ventilation with 40% O2, followed by 5 min exposure to 10% O2 and 2 min of recovery. In the majority of animals (7 out of 11), hypoxia had no effect on lung mechanics compared with control trials. Four animals responded to hypoxia with an increase in resistance and a decrease in compliance. Resistance remained elevated throughout the hypoxia with an average maximal increase of 47.2 +/- 22.2% (SD). Dynamic compliance was significantly decreased at the 2nd, 3rd, and 4th min only of hypoxia. Bilateral vagotomy abolished the response in the four animals and hypoxia had no effect on mechanics postvagotomy. Our data suggest that in most cases changes in lung mechanics do not play a causal role in the biphasic ventilatory response to hypoxia seen in the newborn.

The intestinal protozoan cryptosporidium is known to cause diarrhea in immunocompromised patients, but few cases have been reported in detail in immunocompetent persons. During a 12-month period, we identified cryptosporidium in the stools of 43 immunocompetent patients. The numbers of cases were increased in those under 4 years old and in those from 30 to 39 years old. Of 30 index cases, 23 (77 per cent) were diagnosed in the late summer or the fall. Fifteen of the 43 patients (35 per cent) had other gastrointestinal pathogens, of which only Giardia lamblia was statistically associated with cryptosporidium. In the 28 patients in whom other gastrointestinal pathogens were not identified, the clinical manifestations were predominantly watery, nonbloody diarrhea and, less commonly, abdominal discomfort, anorexia, fever, nausea, and weight loss. The infection was self-limited in all 43 patients. Clustering of cases occurred in a day-care center and in two families. These clinical observations confirm worldwide findings and suggest that cryptosporidium is a relatively common nonviral cause of self-limited diarrhea in immunocompetent persons in the northeastern United States.

A simple quantitative model for speech development is proposed. The model is developed from observations of two systems, one that of normal hearing children and the other that of those who suffer from congenital profound deafness. Comparison of the two systems provides clues to the type of controls needed to produce normal speech. The possible nonlinear controls which may be used during the development of both the suprasegmental and segmental aspects of speech are identified. The linguistic components of speech are ignored. The interdependence of perceptual systems during developmental phases is taken into account and the importance of the associative cortex in speech-motor control is formulated. Deaf persons may employ the tactile system in developing speech; the distinctive unit of code is called a tacheme.

Detached ciliary tufts of columnar epithelial cells from the female genital tract may be mistakenly identified as protozoa when examined in wet mounts of fluid specimens in the laboratory because of their appearance and motility, although they are generally identified correctly in fixed specimens prepared for cytologic examination. A case of such mistaken identity in specimens from a gynecologic patient was documented, and the literature on ciliary tufts was reviewed. Infectious disease and gynecology consultants should be alert to the potential confusion arising from the presence of ciliary tufts in body fluids.

A novel 8-aminoquinolone compound, 8(6-4' 3-hydroxybutyl)piperazin-1'-ylhexylamino)-6-methoxyquinoline di(hydrogen maleate), moxipraquine, 349C59, was shown to be active against experimental infections with Trypanosoma cruzi. It was effective in suppressing parasitaemia but did not eradicate the infection from mice or guinea-pigs. Other clinically tested drugs, including nifurtimox, were likewise incapable of eradicating the parasite from infected mice. Moxipraquine was less potent against mouse infections with strain Peru than it was against other strains of T. cruzi. In limited tests, moxipraquine was effective on experimental infections of Leishmania major, L. mexicana mexicana and L. brasiliensis panamensis but not L.b. brasiliensis. Significant foetal toxicity, observed experimentally in rats and rabbits, resulted in the termination of clinical trials.

Two cases of subcutaneous dirofilariasis acquired in Ontario and Vermont are reported. The parasites in these and eight cases previously reported from the northern United States and Canada are classified as resembling Dirofilaria ursi, a primarily subcutaneous parasite of bears, or D. subdermata of porcupines, in the same region. A distinguishing morphological feature of the D. ursi-like group is the presence of distinct longitudinal cuticular ridges regularly and widely spaced on the outer surface, and usually evident even when the worms are necrotic. In the 10 known cases, all patients were women, and the usual location of nodules containing the worms was the scalp or a covered part of the upper body where blackflies, the intermediate hosts of D. ursi, normally feed.