On-line determination and control of the water content in a continuous conversion reactor using NIR spectroscopy.

On-line near infrared spectroscopy was used to determine the water content in a continuous conversion reactor. The NIR predictions were incorporated into the distributed control system (DCS) which then controlled the addition of water to the reactor. The conversion reaction utilizes methanol, water, sodium carbonate and a reactant. Control of the water content is important for a number of reasons. At elevated water levels, a competing hydrolysis reaction increases along with the product solubility in the mother liquor leading to product losses. At reduced water levels, the product becomes anhydrous and the reaction mixture becomes gelatinous, necessitating a shutdown of the reactor for cleaning. The previous procedure for monitoring water was to remove a sample once per hour, transfer the sample to the laboratory, and run a Karl Fisher assay. Upon obtaining results from the lab, an operator would manually adjust the water inlet valve to the reactor. NIR spectroscopy in an on-line mode allows spectra to be collected every 200 s markedly increasing the frequency of results. A partial least squares model was constructed, validated and successfully implemented to predict the water content of the reactor. Further, by feeding the results to the process DCS, water additions to the reactor were fully automated. The increased frequency of sampling by NIR led to an improvement in the control of the water content and decreased the normal amount of equipment downtime. These factors improved process stability and recovery thereby generating an estimated $500,000 in savings over the course of the campaign.

On-line monitoring of powder blend homogeneity by near-infrared spectroscopy.

Near-infrared spectroscopy is evaluated as an on-line technique for monitoring the homogeneity of a pharmaceutical blend during the blending process. Blends containing 10% sodium benzoate (model active), which provided an aromatic functionality typical of many pharmaceutical compounds, 39% microcrystalline cellulose (Avicel PH102), 50% lactose, and 1% magnesium stearate were developed to mimic the properties of an actual pharmaceutical blend. A twin-shell V-blender was modified to allow installation of a diffuse reflectance fiber-optic probe at the axis of rotation, and spectra were collected during three experiments using a commercially available near-infrared spectrophotometer. In each experiment, blender control and spectral data collection were controlled by a compilation of software packages. The experiments detected spectral changes which eventually converged to a point of constant variance. Further analysis of the spectral data showed the blend is homogeneous long before a typical blending period is complete. Near-infrared spectroscopy has proven to be a feasible and effective method for the "real time" noninvasive determination of homogeneity in a pharmaceutical blend.

Cognitive function testing in comprehensive geriatric assessment. A comparison of cognitive test performance in residential and clinic settings.

Tests of cognitive function are frequently used in geriatric assessment, but the effect of test setting has rarely been explored. To determine the effect of testing site on the performance of elderly patients undergoing a comprehensive geriatric assessment, we administered the Mini-Mental State Exam to 116 geriatric patients in the clinic and at their residence. Their cognitive abilities varied from normal to severely impaired. The patients' scores were 1.5 +/- 3.6 (mean +/- SD) higher at their residence. The clinical importance of a difference in score of 1.5 is not clear. For this reason a second analysis was performed in which a difference in scores of five points or greater between settings was considered clinically meaningful. Twenty-five percent (29 of 116) differed by five points or more. Of these 29 patients, 22 (76%) tested better in the residential setting. These differences were statistically significant (P = .001). We conclude that the testing site may affect test performance and that in-home assessment may reveal the optimal cognitive function of geriatric patients.

Prevalence of postburn depression following burn injury.

We examined the prevalence of depression after burn injury in 139 adults treated at a major burn center. Interviews were held from one to eight years following the burn. Our subsample, taken from 882 patients treated over a six-year period, comprised all patients with 30% total body surface area burns and a random sample of those with burns of lesser severity. We considered 17 possible predictors of depression (including the severity and placement of the burn and the patient's age, educational background, medical history, employment status, income level, and emotional and psychiatric history). We found that it is the person, rather than the injury, that best predicts postburn depression. The factor most strongly linked with depression was a past history of emotional disturbance. However, after being burned, a significant number of even previously well-adjusted patients show clinical postburn depression.

Analysis of 585 burn patients hospitalized over a 6-year period. Part I: Demographic comparison with the population of origin.

There has been a large number of studies on the epidemiology, aetiology and demography of burn injury. However, no previous study has been able to compare the burn population with detailed data on the general population from which it derived. Data on the Standard Metropolitan Area (SMSA) of San Diego provided by the US Census Reports of 1970 and 1980 have made this possible. In this paper we have examined age, sex, ethnic origin, level of education, gross family income and occupation in a population of 585 burn patients taken from this SMSA.

Analysis of 585 burn patients hospitalized over a 6-year period. Part II: Aetiological data.

In a population of 585 burn patients from a well-defined urban area, the contribution of a number of factors to the occurrence of the burn injury is examined. These are: place where burned; activity of the patient at the time; contribution of various appliances and materials; the influence of clothing on the extent of the injury. These findings should prove helpful in future efforts at burn prevention.

Analysis of 585 burn patients hospitalized over a 6-year period. Part III: Psychosocial data.

We have examined the physical and psychosocial aberrations found in a series of 585 hospitalized burn patients. The implications of this data have been discussed as they apply to identifying persons at high risk for burn injury, and as they apply to estimation of the prognosis in severe burn injury. This is a step towards identifying a psychosocial profile for the evaluation of burned patients.

Effects of caffeine on tactile startle in rats.

The effects of graded doses of caffeine (1.5 to 100 mg/kg) on tactile startle responding were examined in rats given 121 air-puff stimuli at 15 second intervals. Doses of caffeine up to 50 mg/kg were found to significantly increase tactile startle consistently throughout the 30 minute test session. The highest dose of caffeine tested initially increased and subsequently decreased startle amplitude. An examination of the time-course of the augmentation in startle produced by 12 mg/kg caffeine revealed that the effect was maximal 15 minutes after the subcutaneous injection. The results are discussed in relation to the differences between the effects reported here for caffeine and the known effects of other psychostimulants.

Simplified scaling for life change events.

A relative simple interval scaling method for adjustment to life change events was compared to the original, more difficult, proportinate scaling method. Ranking of life events by both methods was extremely similar. Evidence also was found that today Americans scale several minor life change events as requiring greater adjustment than that estimated for these events a decade earlier.

Alcohol intake, ratio of plasma alpha-amino-n-butyric acid to leucine, and gamma-glutamyl transpeptidase in nonalcoholics.

In a sample of healthy men, there appeared to be no relationship between reported drinking and the ratio of plasma alpha-amino-n-butyric acid to leucine or between this ratio and an index of liver dysfunction (gamma-glutamyl transpeptidase).

Brief group therapy in myocardial infarction rehabilitation: three- to four-year follow-up of a controlled trial.

A trial of brief group therapy as part of a rehabilitation program for postmyocardial infarction (MI) patients was carried out. Forty-four patients surviving their first MI were randomly allocated to either group therapy or control group status and were followed over 4 years. An additional group of 17 patients were referred for post-MI group therapy sessions after the termination of the controlled experiment and were followed for 3 years. Patients who received group therapy had significantly less follow-up coronary morbidity and mortality, and returned to work at significant higher percentages than control patients. Although neither group therapy nor control group patients meaningfully altered conventional coronary risk factors, group therapy patients (in the controlled trial) successfully altered selected coronary-prone behaviors. Educational information regarding the physiological and psychological aspects of coronary heart disease, presented in the group therapy sessions, was forgotten over follow-up. It is concluded that the supportive aspects of the group therapy experience played the most important role in determining the rehabilitation advantages seen for treatment patients.

Therapeutic consequences of antitumour drug interactions: methotrexate and 5-fluorouracil in the chemotherapy of C3H mice with transplanted mammary adenocarcinoma.

Methotrexate and 5-fluorouracil at fixed dosages of 1.5 mg/kg and 50 mg/kg, respectively, were employed in combination chemotherapy for transplanted mammary adenocarcinoma in C3H mice. Tumour regression analyses demonstrated the importance of drug sequence and scheduling. Significantly, a drug synergism and antagonism was exhibited under certain conditions. Results indicated a superior therapeutic efficacy when methotrexate was administered 6-12 h before 5-fluorouracil; the reverse proved antagonistic. However, at longer intervals a commutative additivity was apparent. Judicious scheduling of methotrexate and 5-fluorouracil would seem appropriate, as both drugs are widely employed in the current management of neoplasms, such as breast carcinoma.

Psychiatric consultation in a Vietnamese refugee camp.

The authors provided psychiatric consultation to medical personnel in charge of a Vietnamese refugee camp in California. Although the emergency measures that supplied clothing, food, shelter, and medical care to nearly 60,000 refugees were immensely successful, consultation was requested to assist with selected mental health problems. The recommendations of the consulting team were related to the stage of camp development: early recommendations concerned easing adaptation to the camp setting; later efforts included creating a psychiatric crisis clinic and carrying out a mental health survey on a random sample of refugees. The results of this survey helped camp directors to understand how refugees responded to the camp experience.

Central nervous system tumors of childhood treated with CCNU, vincristine, and radiation.

CCNU was used in the treatment of 18 patients with childhood tumors of the CNS. Severe bone-marrow toxicity was noted. The initial dose was 130 mg/m2 given every 6 weeks, but it was often necessary to reduce the dose and prolong the interval between doses. The toxicity appeared to be much the same whether previous radiotherapy had been given to the whole CNS or to the brain only. In assessable patients with pur medulloblastoma, three out of three showed marked responses to CCNU. In those with a mixture of medulloblastoma and other tumor components, two out of two showed responses to CCNU. In children with astrocytomata of various types, only two out of six showed responses to CCNU, and in these the degree of response was slight. The results suggest that CCNU is a useful treatment for medulloblastoma but its value in the treatment of childhood astrocytoma is uncertain. In 6 patients who received both radiotherapy and CCNU, the contribution of the CCNU was not assessable.