A review of the psychological aspects of space flight

Instances of overt, serious functional impairment of space crews caused by adverse psychologic responses have not been scientifically documented. However, transient disorientation, spatial illusions, and visual disturbances as well as anomalous myopias, sleep disturbances, and instances of substandard performance have been described. Moreover, anecdotal information describes significant psychologic aberrations in space flight. Adequate scientific data are lacking for optimal psychological and psychophysiological methods for crew selection, training, and performance evaluation, for identifying key psychosocial factors for crew compatibility, cohesiveness, and productivity, and for determining the effects of space flight on perceptual, intellectual, and motor skills. The ad hoc Working Group, convened to review psychological aspects of space flight, favored establishment of a comprehensive research and development program to address the deficiencies identified in the study.

Occupational exposure to chlorinated organic solvents and its effect on the renal excretion of N-acetyl-beta-D-glucosaminidase

Organic chlorinated hydrocarbon solvents are known to be nephrotoxic. However, very little is known about renal integrity after occupational exposure to these solvents. Increased urinary N-acetyl-beta-D-glucosaminidase (NAG) excretion caused by necrosis of renal tubular cells can be used as a marker for nephropathy. In this study trichloroethylene (TRI), trichloroethane and freon 113 exposed persons from metal industries have been clinically investigated, and urine samples analysed for NAG activity and for trichloroacetic acid concentration. In order to analyse for possible subclinical kidney damage a group of diabetic patients with subclinical nephropathy served as positive controls. A significant higher NAG activity (p less than 0.001) was found in the group of exposed workers as compared to the control group. About 10% of the exposed workers had an enhanced NAG value, corresponding to the level of diabetic patients with subclinical nephropathy. Increased NAG activity was observed in previously TRI-exposed persons, which might indicate induction of an autoimmune renal necrosis.

Effects of oral cimetidine on plasma concentrations of phenylbutazone in horses

Phenylbutazone was administered to six Thoroughbred horses in a cross-over study in which the horses received cimetidine pretreatment or no cimetidine pretreatment. Blood samples were collected at various times for 48 h after phenylbutazone administration and the plasma was analysed for phenylbutazone. Cimetidine pretreatment elevated phenylbutazone plasma concentrations during the first 8 h after phenylbutazone administration. The absorption rate, maximum phenylbutazone plasma concentrations and AUC were significantly greater with cimetidine pretreatment. The half-life of phenylbutazone did not change with cimetidine pretreatment; however, lower plasma concentrations of the metabolite gamma-hydroxyphenylbutazone were observed with cimetidine pretreatments. Plasma concentrations of the metabolite oxyphenbutazone were unchanged with cimetidine pretreatment compared to control values. Twenty-four-hour plasma concentrations of phenylbutazone were not different from control values with cimetidine pretreatment. This study suggests that concurrent treatment with cimetidine and phenylbutazone 24 h before race time does not result in elevations of plasma phenylbutazone concentrations above control values.

Norethindrone disposition following x-ionizing radiation in rats

The pharmacokinetics of norethindrone were investigated in rats exposed to ionizing x-irradiation. Norethindrone was administered by IV bolus injection immediately after, 3 days or 7 days after exposure to 100 rads, 300 rads, 600 rads, and sham x-irradiation. No observable change in norethindrone pharmacokinetics was observed in rats immediately after exposure to all dose levels of x-rays. At three days post irradiation there was an increase in volume of distribution (Vdarea) from 5.55 +/- 0.93 l/kg for sham irradiated to 11.28 +/- 0.74 l/kg for 600 rad rats. Half-life increased after exposure to x-rays from 45.2 +/- 4.5 minutes for sham irradiated to 85.5 +/- 12.1 minutes for 600 rads dose. The Mean Residence Time (MRT) increased from 56.7 +/- 5.6 minutes to 96.4 +/- 13.6 minutes after exposure to 600 rads. This same trend was present 7 days post irradiation but was not nearly as pronounced. No significant differences were observed in total body clearance in irradiated versus sham irradiated animals. As norethindrone is excreted as metabolites via hepatic biotransformation, these findings imply that this process is not affected by irradiation for drugs with high hepatic extraction ratios. Increased distribution of norethindrone to peripheral tissues results in a longer MRT for irradiated animals which could result from radiation induced increase in membrane permeability.

Ethyl lactate-ethanol-water cosolvent for intravenous theophylline

Theophylline was dissolved in an ethyl lactate-ethanol-water cosolvent system and administered intravenously to rabbits. There were no observed differences in theophylline pharmacokinetics in rabbits administered in the cosolvent system when compared to theophylline administered as Aminophylline Injection USP, with the half-life being 4.5 hours and 4.3 hours respectively. Theophylline dissolved in the cosolvent system caused less erythrocyte hemolysis when exposed to blood in vitro than Aminophylline Injection USP. There were no observed toxicities in any rabbits during intravenous administration of theophylline dissolved in the cosolvent system or for Aminophylline Injection USP.

Stability of an analgesic-sedative combination in glass and plastic single-dose syringes

The stability of a combination of chlorpromazine hydrochloride (6.25 mg/mL), hydroxyzine hydrochloride (12.5 mg/mL), and meperidine hydrochloride (25 mg/mL) in glass and plastic syringes was studied. Syringes (glass 1.5 mL, plastic 3.0 mL) containing the combination drug solution were stored at 4, 25, and 44 degrees C. At 0,7,30,60,90,180, and 366 days after preparation, samples were visually inspected and tested for pH. Drug concentrations were determined by gas chromatography. No significant changes in drug concentration were apparent in any of the samples stored at 4 degrees C or 25 degrees C. Samples in both glass and plastic syringes stored at 44 degrees C turned yellow by day 30 and continued to darken throughout the study period. At the concentrations tested, chlorpromazine hydrochloride, hydroxyzine hydrochloride, and meperidine hydrochloride combined in glass or plastic syringes are stable for 366 days when stored at 4 degrees C and 25 degrees C. Degradation occurs at higher temperatures.

Neutron activation of iron tablets to evaluate the effects of glycine on iron absorption

Neutron bombardment (neutron flux, 3 X 10(12) neutrons/cm2/s) of prepared iron tablets containing glycine-iron or iron alone was performed to prepare radioactive tablets to assess the effects of glycine on iron absorption from tableted formulations. No interfering isotopes of sufficient quantity were generated during neutron activation of the iron tablets. Cobalt-60 was the major trace mineral detected and accounted for only 1.3% of the total activity. There may have been trace amounts of zinc-65 or chromium-51 present, but they were not detectable above background radioactivity in the final tablet produced. Iron-59 represented greater than 98% of the radioactivity present in the tablets used in the study. Glycine-containing iron tablets produced dramatically higher amounts of iron in blood and tissues of rabbits (p less than 0.05) than did the same tablet formulations without glycine. The area under the iron blood concentration-time curve over 4 h increased by 67% with glycine added to the formulation over control iron tablets. Iron concentrations in tissues 4 h after iron administration was in the order of blood greater than liver greater than heart greater than kidney greater than muscle.

The prehospital use of external counterpressure: does MAST make a difference?

Military anti-shock trousers (MAST) have achieved widespread civilian usage because of reported effectiveness in treating hypovolemic shock. The literature, however, consists of either case reports or series in which no controls were evaluated. No published reports exist which compare similar groups of patients treated with and without MAST in the pre-hospital setting. We reviewed the paramedic and emergency department records of 226 patients sustaining moderate to severe trauma who were transported to San Francisco General Hospital by paramedics over a 15 month period. MAST usage during this period was approximately random as a result of logistical and training constraints. For analysis, patients were divided into two groups: those in whom MAST was applied and inflated during transport and those in whom it was not used. Paramedic interventions other than MAST were similar in both groups. Trauma Scores (TS), and blood pressure index (greater than 90 = 4, 70-89 = 3, 50-69 = 2, 0-49 = 1, no pulse = 0), were calculated for initial field observations and initial emergency room evaluation after hospital arrival. Patients with isolated head injury were excluded. The average change in TS and BP index (E.R.--field value) was calculated for MAST and non-MAST groups of patients. Mortality and total field times were also evaluated. Average TS and BP index increased slightly in both groups. Use of MAST produced no significant improvement in trauma score, BP index, or mortality over non-MAST patients. There was no demonstrable field benefit of MAST in fully arrested patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of divalent amino acids on iron absorption

Solutions of each of 10 amino acids or ascorbic acid were mixed with iron and orally administered to rats. Iron was absorbed to a statistically significantly greater extent (p less than 0.05) when mixed with asparagine, glycine, serine, or ascorbic acid as compared with a control solution of iron. The largest effects were for asparagine and glycine, which also increased iron absorption to a significantly greater extent (p less than 0.001) than did serine or ascorbic acid. No statistically significant increase in iron absorption occurred when any of the other amino acids was mixed with iron. The extent of iron absorption from each test solution, as measured by area under the concentration of iron-59 in the blood-time curve (r2 = 0.0002), and the initial rate of iron absorption for each test solution (r2 = 0.01) showed no correlation with the stability constant of the amino acid-iron complex.

Influence of cimetidine on the disposition of ibuprofen in the rat

Ibuprofen is a non-steroidal anti-inflammatory agent which is extensively metabolized in both man and the rat. Cimetidine is a well known H2 antagonist which is known to inhibit microsomal enzyme drug metabolism. The influence of cimetidine on the disposition of ibuprofen was studied in Sprague-Dawley rats. Pretreatment with cimetidine was found to increase both the rate and extent of absorption of ibuprofen. Cimetidine treatment also inhibited acidification of gastric fluid. Pretreatment with SKF525A increased ibuprofen half-life but not absorption. Additional studies are necessary to determine the effect of cimetidine on the half-life and absorption of ibuprofen in man.

In vivo release of norethindrone coupled to a biodegradable poly(alpha-amino acid) drug delivery system

The in vivo release of norethindrone from a biodegradable steroid-polymer conjugate was studied in rats. The drug-polymer conjugate, consisting of [3H]norethindrone coupled via a 17-carbonate bond to poly-N5-(3-hydroxypropyl)-L-glutamine was administered to female rats by subcutaneous injection. The in vivo release of steroid, determined by measuring the daily radioactivity output in urine and feces, was fairly constant though it showed a gradual decrease during the 9-month study period. The data indicate that this biodegradable norethindrone-polymer conjugate is a potential candidate for the controlled delivery of norethindrone to effect long-term contraception.

Pulmonary extravascular fluid accumulation following intracranial injury

Previous investigations have reported an 11 to 71% incidence of pulmonary edema following CNS injury, based on post-mortem examinations. No premortem assessment to date has been made of the frequency and severity of in vivo pulmonary fluid accumulation following acute head injury. The thermal green dye technique was used to objectively determine extravascular lung water (EVLW) in 18 comatose patients with severe acute intracranial injuries resulting from trauma or spontaneous subarachnoid hemorrhage. Patients with aspiration, lung contusion, or pneumonia were excluded from the study. Control values for EVLW were obtained on admission from a group of 13 traumatized patients without head injury or evidence of pulmonary disease or injury. Intracranial injury patients who had EVLW values greater than two standard deviations above the control group mean were considered to have pulmonary edema. The incidence of pulmonary edema in this series was 50% (9/18). Extravascular lung water was determined post mortem in five patients using the gravimetric method of Pearce. The results suggest that pulmonary edema is a distinct clinical event occurring frequently after acute intracranial injury. Edema appears to be mediated by increased pulmonary microvascular permeability, and is not primarily dependent on postinjury changes in intracranial pressure or pulmonary vascular pressures.

Evaluation of the effects of palatal augmentation on partial glossectomy speech

Patients who have had surgical removal of part of the tongue are left with varying degrees of speech deficiencies. Augmentation of the palate has been suggested as a means of compensation for this deficiency. This pilot study suggests a technique for evaluating prosthodontic efforts to improve speech for partial glossectomy patients. Although firm conclusions cannot be based on the observations of one patient, it appears that both the shape of the palatal surface and the contour of the cavity size anterior to the tongue are important factors to be considered in prosthodontic efforts to optimize fricative sound production for partial glossectomy patients. Further studies with patients who have a wider variety of tongue resections are indicated. The technique described is an effective one for further studies.

Effect of inhalation injury on lung water accumulation

Fourteen thermally injured patients with severe inhalation injury were sequentially studied with the thermal-green dye double indicator dilution technique of extravascular lung water (EVLW) measurement. Eight females and six males (average age, 49 years, and average thermal burn, 37% body surface) were studied for 2-31 days postinjury. All were burned in a closed space, had facial burns, soot in their sputum, and a mean carboxyhemoglobin level of 30%. Nine patients died, six of sepsis, one each of acute renal failure, hepatorenal syndrome, and anoxic brain damage. Mean EVLW on admission was 7.0 +/- 2.9 ml/kg and remained normal in the five survivors and in the patients dying of acute renal failure and anoxic brain damage. Six patients had increases in EVLW, caused by altered pulmonary capillary permeability in five and by elevation of hydrostatic pressures in one patient (hepatorenal death). Of the five patients with permeability edema, one appeared to result from a direct early effect of inhalation injury resulting in an EVLW of 13.3 ml/kg on admission. The other four patients had EVLW increases after the onset of sepsis, resulting in a mean EVLW of 23.2 +/0- 7.2 ml/kg at death (p less than 0.01). Seventy-one per cent of all patients developed pneumonia, which appears to have caused an EVLW increase in one patient; the other EVLW increases were caused by systemic sepsis. In our present study of 14 patients with definite severe inhalation injury only one had an early increase in EVLW directly related to the inhalation injury, an early effect on capillary permeability presumably caused by direct chemical toxicity of inhaled gases. The remaining four cases of permeability edema occurred 4-24 days postinjury and resulted from burn wound or pulmonary sepsis. We thus conclude that increases in EVLW after thermal and inhalational injury are primarily caused by systemic or pulmonary sepsis, and have a delayed onset. Early increases in EVLW may be a result of the chemical toxicity of inhaled gases but are very uncommon, moderate in degree, and are seen only with the severest cases of inhalation injury.

Progabide: a controlled trial in partial epilepsy

Progabide (SL 76002) was studied in a randomized double-blind crossover trial using 20 outpatients suffering from partial complex seizures. Progabide was added to the concomitant antiepileptic treatment in a fixed dosage schedule. The design included an open therapy control unit. No significant difference was established between the number of partial seizures during treatment with progabide and placebo. A trend was observed for lower seizure frequency of secondary generalized seizures during treatment with progabide. Only mild and transient side effects were observed. There was no difference between the side effects of progabide and placebo.

Stability of three oral liquid drug products repackaged in unit dose containers

Stability of oral liquid forms of cimetidine hydrochloride, furosemide, and theophylline repackaged in polypropylene oral syringes and glass vials was assessed. Commercial preparations of each product were used; 2-ml quantities were placed in both types of container and stored at 4, 25, 44, 60, and 76 degrees C. Six samples from each container type at each temperature were tested at various times. Stability was defined as no greater than 10% loss of labeled potency. Assay was by high-performance liquid chromatography. All three drugs retained more than 90% of label claim in both types of containers after 180 days at 4 degrees C and 25 degrees C. For cimetidine hydrochloride and furosemide at these temperatures, there was no significant difference in concentration by container type; at the higher storage temperatures, the degradation rate in polypropylene syringes was significantly faster. For theophylline, loss of volume of 10% or greater occurred after 60 days at temperatures greater than 25 degrees C for both container types. Drug loss at higher temperatures was attributed to precipitation of theophylline out of the elixir rather than chemical degradation. Oral liquid cimetidine hydrochloride, furosemide, and theophylline repackaged in either polypropylene oral syringes or glass vials can be stored at 4 degrees C and 25 degrees C for 180 days with less than 10% loss of potency.

The measurement of extravascular lung water by thermal-green dye indicator dilution

The theory and practice of the thermal-dye indicator-dilution method for measurement of EVLW has been discussed, and all available animal data from our laboratory correlating EVTV and gravimetric EVLW have been presented. The method appears to function well over the entire range of edema seen , and to be minimally dependent on cardiac output. Thermal-indicator loss does not seem to be a significant problem and does not impair the accuracy of this method. Out results are consistent with earlier works in the field in identifying significant differences between the isotopic EVLW methods and the thermal-dye method, and it seems likely that these differences are due to the much greater diffusion rate of the thermal indicator.

Stability of valproate sodium syrup in various unit dose containers

The stability of valproate sodium syrup repackaged in three types of unit dose containers was studied. Two-millimeter samples of commercial valproate sodium syrup 250 mg/5 ml (of valproic acid) were packaged in polypropylene oral syringes, glass oral syringes, and glass vials (126 of each type). These were stored at 4, 25, or 60 degrees C and assayed for valproic acid concentration using gas chromatography at 0, 5, 10, 20, 30, 90, and 180 days. Polypropylene syringes that were stored for 180 days at 4 and 25 degrees C were rinsed and put in chloroform 50 ml; valproic acid concentration was determined daily for 12 days. Valproate sodium syrup repackaged in glass oral syringes and glass vials retained 95% of valproic acid label claim after storage at 4 and 25 degrees C for 180 days, while valproate sodium syrup repackaged in polypropylene oral syringes did not retain 90% of label claim after storage for 20 days at 4 or 25 degrees C. All samples stored at 60 degrees C had greater loss than those stored at lower temperatures. An average of 86% of the drug lost from the polypropylene syringes was recovered in 12 days during the desorption experiment (range 80-92%). Repackaging valproate sodium syrup in unit dose glass vials or glass syringes resulted in retention of 95% of valproic acid label claim after storage for 180 days at 4 and 25 degrees C. Repackaging of this drug product in polypropylene oral syringes is not recommended.

Determination of acetaldehyde in human blood by a gas chromatographic method with negligible artefactual acetaldehyde formation

A method is described for determination of acetaldehyde in blood by head space gas chromatography. The method utilizes sodium nitrite-sulfosalicylic acid as an inhibitor of the ethanol oxidizing systems by means of which the interference of ethanol is reduced considerably. The detection limit was 0.4 mumol/l, the recovery 101.5 +/- 5.2% and the coefficient of variation was 7.8% (1.5 mumol/1 acetaldehyde). There was no disappearance of acetaldehyde if the head space vials were kept at -20 degree C for 24 h. In the comparison study with the semicarbazide method our results were 0.7-4.1 mumol/l lower. The values for acetaldehyde in blood after ethanol ingestion (0.5 g/kg) by volunteers were 0.5-1.3 mumol/l.

Influence of disulfiram on the serum concentration of carbamazepine in patients with epilepsy

Treatment of alcoholics with phenytoin and disulfiram (DI) simultaneously is complicated and inexpedient because of the marked drug interaction. The aim of this study was to investigate whether an interaction exists between DI and carbamazepine (CBZ). The serum levels of CBZ and the metabolite CBZ-10, 11-epoxide were measured by high-pressure liquid chromatography in seven out-patients with epilepsy, on monotherapy with CBZ, before and during two weeks administration of DI. Five patients completed the investigation. None were alcoholics. The changes in the serum levels were insignificant, i.e. without clinical important. Moreover, uncontrolled clinical experience has not indicated any interaction between DI and CBZ. Thus the influence of DI on the metabolism of CBZ is probably negligible. CBZ is suggested, therefore, when anticonvulsive therapy is needed by alcoholics in treatment with DI.

Fricative duration in esophageal speech

Comparative observations were made of fricative (/s/ and /z/) durations of normal and esophageal speakers. Differences between the average durational characteristics of fricatives spoken by normal and esophageal speakers varied systematically as a function of their voicing features. Findings were interpreted to lend additional support to the following views: (1) laryngeal amputation occasions widespread changes in speech production, (2) esophageal speakers exhibit articulatory behaviors, and (3) esophageal speakers retain fricative durational voicing contrast features.

Lung water changes after thermal injury. The effects of crystalloid resuscitation and sepsis

Respiratory failure after thermal injury is common, but the etiologic roles of high volume crystalloid resuscitation, hypoproteinemia, inhalation injury, or sepsis have not been specifically defined in human studies. We used the thermal-green dye double indicator dilution measurement of extravascular lung water (EVLW) to follow daily lung water changes in seven severly burned adult patients, resuscitated with only crystalloid solutions. An average weight gain of 21.3 kg, a 30% increase (p < 0.001), was present two to three days after admission. Admission EVLW for all patients was 7.9 +/- 1.2 ml/kg, (means +/- SD), and EVLW at the time of maximal weight gain was 5.9 +/- 1.4 ml/kg, a 25% decrease (p < 0.05). Admission pulmonary artery wedge pressure (PAWP) was 8 +/- 3 mmHG, which was not significantly different from PAWP of 13 +/- 4 mmHg at the time of maximal weight gain. In the three patients who died of sepsis, their terminal weight averaged 17.8 kg (27%) above their admitting weight (p < 0.01) and EVLW was 26.4 +/- 4.4 ml/kg, a 200% increase (p < 0.02) from admission. Their terminal PAWP averaged 22 +/- 2 mmHg, a 170% increase (p < 0.005). None of these patients had an increase in EVLW until clinical signs of sepsis occurred and the rise in EVLW preceded the rise in PAWP. Calculated mean plasma colloid osmotic pressure (PCOP) on admission was 20.7 +/- 4.9 mmHg; at the time of maximal weight gain, it was 8.6 +/- 1.7 mmHg (p < 0.001). The PCOP-PAWP gradient fell to -4 +/- 4 mmHg (p < 0.001) at the time of maximal weight gain and remained less than +4 mmHg throughout the study period in all patients. We conclude that massive crystalloid resuscitation while maintaining PAWP below 15 mmHg does not cause an increase in EVLW during the first four days after thermal injury. EVLW actually decreases slightly in all patients despite marked weight gain, hypoproteinemia and a negative PCOP-PAWP gradient. EVLW does not correlate with the PCOP-PAWP gradient in either septic or nonseptic periods. Three patients had severe inhalational injury and normal EVLW for the first four postburn days. It therefore appears that significant interstitial edema does not result from inhalational injury. There is also no evidence that thermal injury causes an early increase in pulmonary capillary permeability. The occurrence of sepsis, however, results in rapid accumulation of lung water, without any change in hydrostatic or osmotic forces. This study supports the primary role of sepsis in altering pulmonary capillary permeability with resulting pulmonary edema.

Gas chromatographic method for the simultaneous determination of hydralazine and its acetylated metabolite in serum using a nitrogen-selective detector

A relatively simple gas chromatographic method has been developed for the quantitative determination of hydralazine simultaneously with its acetylated metabolite, 3-methyl-s-triazolo[3,4-alpha]phthalazine (MTP). The proteins were removed by means of sulfosalicylic acid and Sure-Sep. On treatment with formic acid, hydralazine and its internal standard were converted into their formylated derivatives. These derivatives, MTP and its internal standard were extracted with toluene and determined by gas chromatography with a nitrogen-selective detector. The lower limits of detection for hydralazine and MTP were 0.13 and 0.27 mumol/l, respectively.

Influence of dextropropoxyphene on steady state serum levels and protein binding of three anti-epileptic drugs in man

Interactions between analgesics and anti-epileptic drugs may sometimes present a serious clinical problem. The aim of the study was to investigate the influence of usually applied doses of dextropropoxyphene (DPX) on the steady state levels of carbamazepine (CBZ), phenytoin (DPH) and phenobarbital (PB). Sixteen patients in monotherapy completed the trial, while four patients dropped out. In patients on CBZ serum levels increased (mean appr. 66%) after 6 days on DPX. In three of the patients a further increase was seen after an additional week on DPX. One patient discontinued the DPX intake because of clinical signs of toxicity, but the remainder were clinically unaffected. CBZ-epoxide levels declined simultaneously. For DPH only a doubtful increase was observed after 1-2 weeks on DPX. For PB an average increase of 20% in serum level was noted after 1 week. The protein binding of CBZ and DPH was not affected. It is concluded that patients on CBZ should be treated only with DPX if monitored properly. Patients on DPH or PB should be followed carefully until further evidence has been produced.

Hormonal polypeptides and amine metabolites in small cell carcinoma of the lung, with special reference to stage and subtypes

To elucidate the ectopic hormonal pattern in patients with small cell carcinoma of the lung, plasma ACTH, serum calcitonin, serum gastrin, plasma glucagon, serum insulin, plasma secretin, plasma VIP, serum growth hormone, serum hCG/LH, the total of serum hCG and hCG-beta-subunit,serum alpha-subunit, serum human placental lactogen, urine ADH, urine 5-HIAA, urine VMA, urine HVA, and urine hCG-LH were measured prior to therapy in 75 patients. Twenty-two patients (29%) had elevated plasma ACTH, and 18 of these had concomitant increased values of corticosteroid in a 24-hour urine sample. Forty-eight patients (64%) were found to have elevated serum calcitonin, and one-third of the patients were diagnosed as having the ectopic ADH syndrome. Serum gastrin concentrations were increased in 20% of the patients, but the elevations were marginal in almost all cases. None of the remaining substances was found to be significantly elevated. Concentrations of plasma ACTH, serum calcitonin, and urine ADH were not found to be correlated with the stage of the disease, and no correlation of these substances with the histological subtypes of small cell carcinoma was disclosed.

Nasalance patterns in esophageal speech

Velopharyngeal activity during esophageal speech was investigated indirectly by use of TONAR II instrumentation, which measures the oral--nasal acoustic ratio. Eight very good esophageal speakers who used an injection type of insufflation served as subjects. Each subject read three standardized passages containing varying amounts of nasal consonants. The results indicated that these speakers have a slower, but functional, velopharyngeal mechanism.

A rapid direct determination of cadmium in blood by anodic stripping voltammetry

This paper describes a rapid, sensitive anodic stripping voltammetry (ASV) method for measuring quantities of cadmium in blood. An advantage of this method is the minimal sample preparation required, using a metal-exchange reagent. A sensitivity of 4 nmol/l can be obtained. The results correlate with those obtained by atomic absorption spectroscopy. Within-run, the coefficient of variation (CV) was 8.9% at a cadmium concentration of 32 nmol/l. Between run CV was 5.4% at 37 nmol/l. The reference interval for blood cadmium concentration was 5-60 nmol/l for non-smokers and 5-85 nmol/l for cigarette-smokers. This method of cadmium analysis shows that ASV is a rapid, sensitive method for determination of blood cadmium in the normal range.

Productive voice onset time characteristics of esophageal speech

The voice onset times (VOT) of a large number of stop-consonant initiated syllables produced by esophageal and normal speakers were measured. Esophageal speakers systematically varied VOT during the production of speech-sound categories with the same manner of production. Average voice onset times associated with the production of prevocalic voiceless stops of esophageal speakers were significantly shorter than those of normal speakers, while takler-group comparisons associated with the production of voiced prevocalic stops were nonsignificant. Voice onset times of both esophageal and normal speakers were differentially sensitive to place of articulation. Findings are discussed in terms of furthering current understanding of how effectively esophageal speakers achieve important phonological contrasts.

Pharmacokinetics of dextropropoxyphene in acute poisoning

Dextropropoxyphene (DP) is a commonly used medicament for suicide attempts in Denmark. Death may occur from respiratory depression or cardiac arrest. Mechanical hyperventilation which induces hypocapnia seems to reduce the occurrence of cardiac complications. In an attempt to relate the clinical events to the plasma concentrations of DP and the major metabolite norpropoxyphene (NP) we studied patients with acute poisoning treated either for 48 h with induced hypocapnia by hyperventilation or under a conservative regime. Hypocapnia was found to lead to a significant increase in the plasma half-life of DP. Under conservative treatment the plasma half-life was 17.9 +/- 6.7 (S.D.) h (n = 6), while under induced hypocapnia the mean of values from 5 patients was 30.5 +/- 6.9 (S.D.) h. Maximum serum levels of DP and NP were, however, significantly higher in the intensively treated patients (n = 7) than in those treated conservatively (n = 9), though less marked for NP compared to DP (DP: 4.9 +/- 2.1/2.4 +/- 1.0 mumol/l, NP: 6.3 +/- 2.4/4.1 +/- 1.7 mumol/l). A concentration dependent renal clearance of NP was not demonstrable. Possible explanations are the following: 1) A change in disposition pattern blood/tissue of DP during hypocapnia. 2) A reduced metabolism DP to NP during hypocapnia. 3) A reduction in other routes of elimination.

Vowel duration characteristics of esophageal speech

The duration of a large number of representative vowels produced by 10 esophageal and nine normal speakers were measured. Overall vowel durations of esophageal speakers were consistently longer than those of normal speakers, indicating that esophageal speakers do not compensate for their striking diminution in air supply for speech by decreasing vowel duration. The differences in the vowel duration characteristics between normal and esophageal speakers were observed to vary systematically as a function of the voicing features of their consonant environments. Specifically, the durations of vowels of esophageal speakers spoken within voiceless consonant environments were consistently longer than those spoken in similar contexts by normal speakers. There were no significant differences between the average durations of vowels spoken by normal and exophageal speakers within voiced consonant speakers differed significantly as a function of the voicing features of their consonant context was interpreted to support the belief that inherent, rule-governed durational features of English are retained following laryngeal amputation.

Characterization of a cobalamin-binding plasma protein from a patient with hepatoma

A cobalamin-binding protein has been purified by affinity chromatography from plasma of a patient with hepatoma and a 10,000-fold increase in the concentration of the plasma cobalamin-binding capacity. The protein behaved as normal transcobalamin I in gel filtration, agar gel electrophoresis, immunoelectrophoresis, precipitation by ammonium sulphate, and cobalamin-binding studies. The protein contained 38 per cent carbohydrate, and the relative molecular mass based on amino acid and carbohydrate analyses was 69,000. The molar absorption coefficient of cyanocobalamin bound to the protein was determined to be 36,000 at 362 nm. On amino acid sequencing, one amino terminal was found, and the first 13 residues were determined as Glu-Ile-Ser/Cys-Glu-Val-Ser/Cys-Glu-Glu-Asx-Tyr-Ile-Arg-Leu/Ile.

What does operator do in complex systems

An effort was made to locate representative data on human activities in complex operational systems. Very little operational data were found which were suitable for our purposes. Therefore, this requirement was compromised and activity data from tests and paper and pencil analyses were used. These data were then classified by two raters according to an adopted taxonomy. It was generally concluded that where activity data have been gathered under operational conditions, they have been useful to design engineers, human factors specialists and systems analysts. It is further noted, however, that additional effort must be devoted to the development of better methods for obtaining data and corresponding criteria of human performance under operational conditions. A discussion of the taxonomy and other techniques indicated that collection of activity data should be feasible under operational conditions. In addition it is suggested that increased standardization and use of operational definition in the development of these techniques might result in improvement of their general applicability.

Individuals and us

Since behavior is a function of both heredity and environment, it is axiomatic that those who directly or indirectly structure the environment determine to some extent the behavior of the residents of that environment. Systems and design engineers are responsible for a very significant proportion of the artifactual elements of a modern society and probably have a much greater influence on human behavior than has been generally recognized. The members of the Human Factors Society have a special responsibility and a unique opportunity to see that equipment and systems are designed so as to take advantage of such qualities of man as creativity, flexibility, etc. Further, insofar as possible the human factors specialist should assure that the jobs and man-machine interactions created by specific designs not only take advantage of man's presence but also contribute positively to his personal development and fulfillment.