Non-weightbearing exercise may increase lumbar spine bone mineral density in healthy postmenopausal women

Seven postmenopausal women exercised regularly at moderate intensities (60-80% of maximum heart rate) for eight months on bicycle ergometers. Evaluation of bone mineral density by dual photon absorptiometry revealed a significant (P < 0.01) + 3.55 +/- 1.43% (mean +/- SE) increase in lumbar spine density in the exercisers compared with the 2.44 +/- 0.81% decrease noted in seven sedentary controls. No significant difference in change in femoral neck density was noted between the two groups (+2.51 +/- 2.10% v -0.74 +/- 0.72% for exercisers and controls, respectively; P > 0.10). Dietary intake of calcium and vitamin D was similar in both groups, as was previous exposure to estrogen replacement therapy. These data provide evidence of a prospective nature that non-weightbearing exercise may be effective in reversing bone loss in healthy postmenopausal women.

Heterotopic ossification. The utility of osteocalcin in diagnosis and management

The status of 12 patients after severe traumatic brain injury was investigated to determine the clinical significance of serum osteocalcin levels during the active phase of neurogenic heterotopic ossification. The diagnosis of heterotopic ossification was confirmed on the basis of radiologic findings. The mean interval between the initial injury and diagnosis of heterotopic ossification was 29 weeks. At the time of diagnosis, serum osteocalcin and total alkaline phosphatase levels were determined along with 24-hour urinary calcium and hydroxyproline excretion. The mean serum osteocalcin level was normal at 4.3 ng/ml (normal range 1.6-6.6 ng/ml) in contrast to the elevated mean values for serum alkaline phosphatase (mean = 173 units/liter; normal range 0-105 units/liter) and urinary hydroxyproline concentration (mean = 39.6 mg/24 h; normal range 7-25 mg/24 hr). Only 17% of the subjects demonstrated an elevated serum osteocalcin level, whereas 58% of the patients had an elevated serum alkaline phosphatase level. Urinary calcium excretion and hydroxyproline excretion were elevated in 33% and 70% of subjects, respectively. These data did not reveal a significant correlation between serum osteocalcin and serum alkaline phosphatase, urinary calcium excretion or urinary hydroxyproline at the time of diagnosis or in serial measurements. Therefore, serum osteocalcin is not a valuable adjunct in confirming the diagnosis of neurogenic heterotopic ossification once the diagnosis has been suggested on the basis of clinical findings and it does not appear to play a role in assessing the maturation of heterotopic ossification.

Aesthetic inlays and onlays: a clinical technique update

Advances in adhesive technology offer the dentist the potential to place tooth-reinforcing restorations with more conservative preparations. At the same time, improvements in tooth-colored restorative materials are yielding high levels of durability and aesthetics. The combination of these events has led to the development of an entirely new class of restorations for posterior teeth, called aesthetic bonded inlays and onlays. The learning objective of this article is to present an updated, simplified, and predictable technique for placing an indirect composite resin inlay or onlay.

A clinical technique for rebonding fractured cusps in posterior teeth

Advances in adhesive dentistry have led to increasingly predictable conservative aesthetic restorative procedures. When trauma results in a clean tooth fracture, perhaps the ultimate in conservation dentistry is achieved by rebonding the fractured piece. The learning objective in this article is the clinical technique for rebonding fractured off tooth segments in posterior teeth.

Weight-training effects on bone mineral density in early postmenopausal women

We tested the hypothesis that weight training would be an effective modality in maintaining or increasing bone mineral density (BMD) at the lumbar spine, femoral neck, and bone mineral content (BMC) at the distal wrist in early postmenopausal women. A total of 17 women completed a 9 month weight-training program, and 9 women served as a control group. Resistance training occurred three times per week using exercises designed to increase muscular strength. Mean change in lumbar BMD in the weight-trained group (1.6 +/- 1.2%, mean +/- SEM) was significantly different from the change in the control group (-3.6 +/- 1.5%, p less than 0.01) over the 9 month period. No significant weight-training effect was detected at the femoral neck or distal wrist site. We conclude that weight training may be a useful exercise modality for maintaining lumbar BMD in early postmenopausal women.

Chronic use of the calcium channel blocker nifedipine has no significant effect on bone metabolism in men

Calcium channel blockers have been reported to have such diverse effects on reduction in protein synthesis, diminished incorporation of proline into new collagen, and decreased hormone release in vitro. The chronic affect of the calcium channel blocker nifedipine was examined in vivo to determine the possible impact of pharmacologic calcium channel blockade on bone metabolism. Eleven Caucasian males treated with an average of 40 mg/d nifedipine for an average of three years were compared to 11 control males matched for age, height, weight, activity level, cardiovascular status, and calcium intake. No significant differences between groups were noted in bone mineral density at the lumbar spine (L2-4), proximal femur (femoral neck, Ward's triangle and trochanter), and proximal and distal radius. There were also no significant differences in parameters of bone turnover (alkaline phosphatase, osteocalcin, urine calcium/creatinine, and hydroxyproline/creatinine ratio), or hormones that might affect calcium metabolism and bone (testosterone, PTH, 25(OH) vitamin D, and calcitonin). In summary, chronic nifedipine use in males is not associated with either a beneficial or adverse effect on bone metabolism.

Fever of unknown origin following traumatic brain injury

Fever is a common complication of a traumatic brain injury, occurring during both the acute-care phase and the rehabilitation phase of recovery. The aetiology of fever in this population may remain obscure because of the presence of cognitive confusion associated with post-traumatic amnesia interfering with history taking and the difficult physical examination. We present a case where recovery from a traumatic brain injury was complicated by a fever of unknown origin that proved to be secondary to lateral sinus thrombophlebitis. This case emphasises the importance of a thorough knowledge of the differential diagnosis for fever that is unique to the traumatic brain injury population.

Intermittent cyclical etidronate treatment of postmenopausal osteoporosis

BACKGROUND

To determine the effects of etidronate (a bisphosphonate that inhibits osteoclast-mediated bone resorption) in the treatment of postmenopausal osteoporosis, we conducted a prospective, two-year, double-blind, placebo-controlled, multicenter study in 429 women who had one to four vertebral compression fractures plus radiographic evidence of osteopenia.

METHODS

The patients were randomly assigned to treatment with phosphate (1.0 g) or placebo twice daily on days 1 through 3, etidronate (400 mg) or placebo daily on days 4 through 17, and supplemental calcium (500 mg) daily on days 18 through 91 (group 1, placebo and placebo; group 2, phosphate and placebo; group 3, placebo and etidronate; and group 4, phosphate and etidronate). The treatment cycles were repeated eight times. The bone density of the spine was measured by dual-photon absorptiometry, and the rates of new vertebral fractures were determined from sequential radiographs.

RESULTS

After two years, the patients receiving etidronate (groups 3 and 4) had significant increases in their mean (+/- SE) spinal bone density (4.2 +/- 0.8 percent and 5.2 +/- 0.7 percent, respectively; P less than 0.017). The rate of new vertebral fractures was reduced by half in the etidronate-treated patients (groups 3 and 4 combined) as compared with the patients who did not receive etidronate (groups 1 and 2 combined) (29.5 vs. 62.9 fractures per 1000 patient-years; P = 0.043); the effect of treatment was most striking in the subgroup of patients with the lowest spinal bone mineral density at base line, in whom fracture rates were reduced by two thirds (42.3 vs. 132.7 fractures per 1000 patient-years; P = 0.004). The addition of phosphate provided no apparent benefit. There were no significant adverse effects of treatment.

CONCLUSIONS

Intermittent cyclical therapy with etidronate for two years significantly increases spinal bone mass and reduces the incidence of new vertebral fractures in women with postmenopausal osteoporosis.

Relationship of new-onset systemic hypertension and normal pressure hydrocephalus

Communicating normal pressure hydrocephalus (NPH) is an important remote complication of traumatic brain injury (TBI). The diagnosis of this hydrocephalus depends largely on clinical signs and symptoms, including cognitive deterioration, gait changes and incontinence. However, many of these signs are also seen during post-traumatic amnesia, making early recognition of this syndrome difficult. A case study of one man post-TBI, who presented with new-onset hypertension as a sign of NPH, prompted a retrospective chart review of all patients admitted over a 2-year period with a diagnosis of NPH. Ninety per cent of patients had one or more of the classic triad of NPH and 25% of patients had symptoms suggestive of raised intracranial pressure (unexplained nausea, headache and visual disturbance). Mean systolic and diastolic blood pressures among the 20 subjects for six consecutive days pre-operatively compared with those for days 8-14 and 15-21 post-operatively showed no significant differences; a subgroup of five patients (25%), however, demonstrated a significant change in blood pressure temporally related to shunting. We suggest that demonstration of new-onset systemic hypertension may also be a clinical sign suggestive of NPH useful in the evaluation of the TBI patient.

Analysis of intentional head gestures to assist computer access by physically disabled people

Any human-computer interface requires both a means of transducing information flowing from the person and a way of classifying this information in a form that can be used by an application program. Since several interface devices exploit the head movements of disabled people to control computers, this paper includes a discussion of existing technologies based on head movements. As an alternative to simple techniques based on pointing to classify this information, this paper studies the possibility of using a combination of pointing and movement gestures to control an application program. By using hidden Markov models to classify movements into 'yes', 'no' and spurious gestures, it was possible to control a simple graphics application program. Subsequent analysis showed that the hidden Markov models achieved a 74% success rate.

The clinical effects of a mouthrinse containing 0.1% octenidine

The purpose of this three-month clinical trial was to evaluate the effects of a 0.1% octenidine mouthrinse on plaque, gingivitis, extrinsic dental stain, and the oral soft tissues. A total of 451 adult volunteer subjects was initiated into the study and given baseline dental examinations. The subjects were stratified into two balanced groups according to gender, plaque, and gingivitis scores. The subjects then received a dental prophylaxis and were provided with dentifrice, toothbrushes, and either a mouthrinse containing 0.1% octenidine dihydrochloride as the active ingredient or a similar placebo mouthrinse. Subjects were instructed to rinse with their assigned product for 30 s twice each day. Examinations were repeated at six weeks (soft-tissue assessment, gingivitis) and three months (soft tissues, plaque, gingivitis, dental stain). The results showed that the group rinsing with 0.1% octenidine had significantly less plaque (39%), gingivitis (50%), and bleeding sites (60%) than the group using the control product, but had significantly higher stain formation and experienced longer prophylaxis times to remove the stain. The oral soft-tissue examinations revealed no differences in the groups in either the numbers or types of lesions noted.

An esthetic, bonded inlay/onlay technique for posterior teeth

In the past, the primary focus of dentistry has been on the alleviation of pain and stopping the progression of disease. The reduction in the prevalence of dental caries, along with advances in adhesive technology, have combined to revolutionize the practice of dentistry today. The modern dentist, using the latest available cosmetic techniques, is now able to satisfy the emotional wants and needs of patients. The public, well informed about the possibilities for anterior esthetics, now desire tooth-colored restorations in the posterior. A new heat- and pressure-curing resin inlay/onlay material and the clinical and laboratory technique for its use are discussed.

Persistence of large molecular weight prolactin secretion during pregnancy in women with macroprolactinemia and its presence in fetal cord blood

Two hyperprolactinemic women with marked increases in circulating 150K PRL were studied from conception throughout pregnancy and delivery. The serum PRL increase during pregnancy in these women was considerably less than that in normal pregnant women (2- and 3.5-fold vs. 10- to 20-fold increases, respectively). The 150K PRL species persisted as the predominant circulating form of PRL throughout each trimester of pregnancy in these women. In contrast, the predominant form of PRL in serum from normal pregnant women was the 22K PRL form. Gel filtration analysis of the umbilical venous cord serum of infants of the macroprolactinemic women demonstrated excessive concentrations of 150K and 50K PRL compared to the molecular species of PRL in the cord serum of normal infants. Repeat analysis of the PRL species in one infant at age 3 yr continued to reveal excessive secretion of 150K PRL (11% vs. less than 6% in normals). These data suggest that genetic influences may be operative in determining PRL heterogeneity.

Effects of nicotine chewing gum on complete dentures and their soft-tissue-bearing areas

One hundred six edentulous subjects were given nicotine-containing chewing gum to evaluate the ability to chew the gum, to observe the adherence of the gum to denture-base materials, and to evaluate the effect of gum chewing on denture-bearing tissues. Prior to the 13-week study, the denture-bearing ridges and the tissue and polished surfaces of the denture were evaluated clinically and photographed. Questionnaires were used to elicit personal habits of the subjects. Of the 59 subjects completing the study, most could manipulate and chew the gum effectively, three-fourths reported that gum adherence was not a problem, and no adverse reaction to oral tissues was observed.

Abnormal cortisol dynamics after traumatic brain injury. Lack of utility in predicting agitation or therapeutic response to tricyclic antidepressants

A period of significant agitation affects up to 30% of patients after traumatic brain injury. The severity and persistence of this agitation may be such as to require pharmacologic methods as part of the treatment plan. To define which subgroup of patients develop severe agitation warranting intervention and to utilize the information to predict therapeutic responsiveness to tricyclic antidepressants (TCA), we examined cortisol dynamics in 35 traumatically brain-injured (TBI) patients 2-10 months post-TBI. Fasting hypercortisolemia (cortisol greater than 20 micrograms/dl) and/or an absent diurnal variation (1600:0800 cortisol greater than 0.5) was noted in more than 70% of TBI subjects. These abnormalities in cortisol dynamics were not predictive of severe agitation (chi 2 = 0, df = 1, P = 0.99 for hypercortisolemia; chi 2 = 0.163, df = 1, P = 0.7 for absent diurnal variation) and did not differ significantly between TCA responders and nonresponders. The cortisol response to dexamethasone suppression was abnormal (postdexamethasone cortisol value at 0800 and 1600 greater than 5 micrograms/dl) in 34 of 35 subjects and was also not predictive of the presence of agitation. The 0800 cortisol was lower in TCA nonresponders in comparison with TCA responders (8.3 +/- 5 v 17.2 +/- 9). In summary, severe TBI warranting inpatient rehabilitation results in hypothalamic-pituitary-adrenal dysfunction. The extent of these abnormalities renders the assessment of cortisol secretion of limited value in making clinical judgments concerning the development of post-traumatic agitation or the management of that agitation by tricyclic therapy.

Clinical effect of a sanguinaria dentifrice on plaque and gingivitis in adults

A clinical trial was conducted to evaluate the effects of a sanguinaria-zinc chloride dentifrice on the prevention of plaque formation and gingivitis. A total of 59 young adults, 18 to 30 years of age, either performed supervised brushing with a 0.075% sanguinaria-0.05% zinc chloride dentifrice, a 0.24% sodium fluoride dentifrice, or rinsed daily with a 0.05% NaF solution. Clinical evaluations for plaque and gingivitis were performed after 7, 14, and 21 days of the test regimen. After 21 days, all subjects resumed twice daily supervised brushing and flossing and post-test evaluations were conducted after two weeks. The results showed that after 7, 14, and 21 days both groups using dentifrices had significantly less plaque and gingivitis than the group using the rinse, and there were no significant differences between the two groups using either the sanguinaria-ZnCl2 or the NaF dentifrices.

An intelligent end-effector for a rehabilitation robot

A UMI RTX robot, modified with limited end-effector sensors and a restricted but effective vision system, is currently used in a developmental education setting for severely physically disabled children. The low physical and cognitive abilities of the children involved in the project require a semi-autonomous robot with environmental sensing capability to operate in a task oriented mode. A variety of low-cost sensors including proximity, distance, force and slip sensors, have been investigated for integration in end-effectors for the RTX robot. The sensors employed on a modified end-effector are detailed and experimental results are presented. A design for an end-effector with integrated sensors is discussed. The integration of the sensor information into a high-level, task-oriented programming language is detailed and examples of high-level control sequences using sensor inputs are presented. Finally, the development of intelligent gripping strategies based on sensor information is discussed.

Orientation Group Monitoring System: an indicator for reversible impairments in cognition during posttraumatic amnesia

During posttraumatic amnesia (PTA), confusion, attention deficits, impaired memory, disorientation, and inability to process external stimuli often preclude accurate assessment of subtle neurologic changes. The Orientation Group Monitoring System (OGMS) has proven to be a simple, useful strategy for assessing cognitive status. Retrospective analysis of weekly aggregate OGMS scores indicated that a decline in performance of 0.23 or greater is clinically significant. Over a one-year period, 27 patients demonstrated significant decrements in OGMS performance, and in 93% of these instances, the decrease was attributable to a medical problem. Adverse effects of medication was the most common etiology of decreased performance (n = 13). Overwhelmingly, the decline in the OGMS score was the first indication of impaired cognition. This monitoring device is therefore useful as an indicator during PTA of declining cognitive function, warranting further medical evaluation.

Amitriptyline for post-traumatic agitation

Agitated behavior is exhibited in up to 30% of patients recovering from a traumatic brain injury. Past treatment protocols have included proactive behavioral management and major tranquilizers. We now report the use of amitriptyline for control of agitation. For a period of over 2 years, 43 male and 15 female patients with a "recent" severe brain injury were admitted for inpatient rehabilitation and subjected to traditional structured programming for treatment of post-traumatic amnesia (PTA). In 20 patients, 18 men and 2 women, where agitation persisted sufficiently to impede rehabilitation despite initiation of structure, amitriptyline was instituted. These patients were of a comparable age (29.4 years for the agitated group versus 25.6 years for the nonagitated group), but the agitated patients had a lower median Rancho Los Amigos Hospital Level of Cognitive Functioning in a comparison to nonagitated patients (V versus VI). All patients were monitored for cognitive performance by the Orientation Group Monitoring System, and a daily account of frequency, severity and type of agitation was recorded. Within 7 days of initiation of therapy, 12 of 17 patients within PTA had dramatic decrease in agitation (5/5 patients at Rancho IV; 4/8 at Rancho V; 3/4 at Rancho VI). Two of the three patients at Rancho VII had agitation that was unresponsive to amitriptyline. The amitriptyline-responsive patients were maintained on the drug through PTA, and the Orientation Group Monitoring System scale demonstrated no impedance in cognitive recovery. Thus, amitriptyline appears most useful as an adjunct for treatment of nondirected agitation; it also has a role in reducing the severity of the directed agitation that is seen during but not after PTA.

Sequential prolactin evaluation of a "cured" patient with recurrence of prolactinoma

Several investigators have suggested that prolactin secretion in some subjects with hyperprolactinemia associated with pituitary macroadenomas may have a resistance to the prolactin inhibitory hormone, dopamine. This report describes a male subject with a prolactinoma whose preoperative evaluation demonstrated a resistance of prolactin release to inhibition by dopamine. Evaluation of prolactin secretion from monolayer culture of his tumor also revealed a resistance to inhibition by dopamine. Four months postoperatively, normal serum prolactin levels and a normal maximal inhibition of prolactin to a dopamine infusion of 0.04 microgram/kg/minute suggested surgical cure. However, a 24-hour prolactin sampling revealed blunted nocturnal augmentation of prolactin release, an early escape of inhibition of prolactin release at 150 minutes from a 0.04 microgram/kg/minute dopamine infusion, and abnormal prolactin response to a low-dose (0.004 microgram/kg/minute) dopamine infusion. Hence, persistent abnormalities in prolactin secretory dynamics were noted with more extensive testing in this patient when he was thought to have been cured. One year postoperatively, the hyperprolactinemia recurred, prolactin release was markedly resistant to dopamine, and an abnormal 24-hour prolactin profile of release was present. Thus, resistance of prolactin secretion to inhibition by dopamine was present in this patient with a prolactinoma. Additionally, an abnormal prolactin response to dopamine was noted to precede the development of hyperprolactinemia with tumor recurrence.

Reality orientation for brain injured patients: group treatment and monitoring of recovery

A reality orientation group for brain injured patients was developed to improve attention deficits, confusion and anterograde amnesia during post-traumatic amnesia (PTA). Seven behavioral objectives are used to define adequate orientation, attention, immediate retention, episodic recall and use of memory aids. Daily performance in each of these areas is aggregated to establish a weekly summary score. Inter-rater reliability was found to be 0.875. The weekly aggregate score assesses recovery during PTA with increases corresponding to qualitative changes in patient progress. This weekly score has proven valuable as a management tool in rehabilitation by indicating when advanced training is warranted, whether a plateau in progress has been reached and when deterioration may be occurring.

Characterization of a large molecular weight prolactin in women with idiopathic hyperprolactinemia and normal menses

This study reports the presence of a large molecular sized PRL as the major form of circulating immunoactive PRL in five women with idiopathic hyperprolactinemia and normal menses. Gel filtration patterns of serum from these patients revealed 98-100% predominance of a 150,000- to 160,000-dalton PRL in contrast to the predominance of the 22,000-dalton species in other hyperprolactinemic patients. This 150,000- to 160,000-dalton PRL was immunologically similar to the 22,000-dalton PRL, and its size on gel filtration was not altered using denaturing conditions. With reduction of disulfide bonds, there was a shift of the peak I PRL to smaller mol wt peptides. In addition, studies of one woman with idiopathic hyperprolactinemia and normal menses revealed preservation of 98% peak I predominance during physiological and pharmacological perturbations of PRL secretion. Finally, assay of the bioactivity of the large molecular sized PRL in the Nb2 rat lymphoma line revealed diminished activity compared to the 22,000-dalton species. This latter finding may help explain the maintenance of normal menses and relative lack of clinical signs in patients with this form of hyperprolactinemia.

Long-term passive enhancement of allogeneic skin grafts with monoclonal antibodies

Monoclonal antibodies (mAb) to graft-specific class I or class II major histocompatibility antigens were tested for their ability to enhance the survival of allogeneic skin transplants. Mutant mouse strains were grafted with wild type tissue to restrict the antigenic differences being recognized. For allogeneic recognition of the class I antigen Ld, mutant BALB/c-H-2dm2 (dm2) mice were grafted with wild type BALB/cKh skin, and two dm2 anti-BALB/cKh mAb, 23-10-1 and 30-5-7, were tested for their ability to enhance. The anti-Ld antibody 23-10-1 (IgM) was found not to enhance the survival of BALB/c skin on dm2 mice. 30-5-7, however, an IgG2a antibody of indistinguishable specificity from 23-10-1, prolonged graft survival for approximately 5 days. For recognition of selected Iab determinants, mutant B6.C-H-2bm12 (bm12) mice were grafted with wild type B6/Kh skin, and mAb specific for the serological change(s) in bm12 were tested for their ability to enhance. The anti-Iab antibody 25-9-17 (IgG2a) was found not to enhance B6 grafts on bm12 mice. However, the enhancement seen with 25-9-17 using (C3H X bm12)F1 recipients was extraordinary, such that treated mice had a mean survival time three times that of the controls. Since 25-9-17 is of C3H origin, these results suggest that allotype (or possibly idiotype) compatibility is important in antibody enhancement. Another anti-Iab antibody 28-16-8 (IgM), also of C3H origin, failed to enhance a B6 graft on (C3H X bm 12)F1 mice.(ABSTRACT TRUNCATED AT 250 WORDS)

Amitriptyline for agitation in head injury

Agitated behavior is frequently associated with traumatic closed head injury. Proactive behavioral intervention is often not successful, and psychopharmacologic agents may result in increasing the targeted behavior through sedation. We describe a 32-year-old woman who developed severe agitation after frontal lobe closed head injury. After failing conservative behavioral management, a therapeutic trial of amitriptyline was initiated. Within two weeks, aggressive outbursts nearly ceased and attention span improved. Serial neuropsychologic assessment before and during amitriptyline therapy documented preservation of cognitive indices along with improvement in Trailmaking tasks. This case suggests that a trial of amitriptyline or other tricyclic antidepressant may be helpful in diminishing agitation associated with frontal lobe damage without impeding cognitive recovery.

Macroprolactinemia presenting like a pituitary tumor

A serum prolactin level greater than 200 ng/ml is almost pathognomonic of a pituitary tumor in a nonpregnant woman. A patient with a three-year history of documented serum prolactin levels of 350 to 400 ng/ml and no evidence of a pituitary adenoma on computed axial tomographic scanning was recently studied. Detailed evaluation included a 24-hour prolactin profile that revealed blunting of the nocturnal augmentation of prolactin release, low-dose dopamine infusion resulting in normal inhibition of prolactin secretion, and a thyrotropin-releasing hormone bolus that showed a blunted stimulation of prolactin release. Analysis of circulating prolactin by column chromatography of her serum revealed that greater than 85 percent of her circulating immunoreactive prolactin had a molecular weight greater than 100,000 daltons (macroprolactin). This contrasts with other hyperprolactinemic states in which 85 percent of the serum prolactin elutes in a 22,000-dalton peak. Hence, macroprolactinemia is apparently a nonprogressive condition and a novel cause of massive hyperprolactinemia.

Atmospheric effects on radiation reflected from soil and vegetation as measured by orbital sensors using various scanning directions

Ground-measured spectral reflectance data for Avondale loam and drought-stressed and unstressed wheat were converted into digital counts for spectral bands 5 and 7 of the Landsat Multispectral Scanner System (MSS). For dry loam, the differences between ratios of MSS bands 7-5 as determined from space and from ground level measurements were 2.3% for clear and 5.6% for turbid atmospheric conditions. By contrast, for wet loam the differences were 10.4 and 29.5%. We found that atmospheric conditions may cause a delay of from 3 to 7 days in the discrimination between drought-stressed and unstressed wheat. For oblique angle observations the atmospheric modification of ground-measured reflectances increased with angle at a greater rate in the 0/180 degrees azimuth than in the 90/270 degrees azimuth. Implications of this result are discussed for oblique angle Système Probatoire d'Observation de la Terre (SPOT), Mapsat, future multispectral linear array system imagery, and wide-angle imagery collected from scanners in high-altitude aircraft.

Plant stress detection by remote measurement of fluorescence

Chlorophyll fluorescence of mature lemon trees was measured with a Fraunhofer line discriminator (FLD). An increase in fluorescence was correlated with plant water stress as measured by stomatal resistance and twig water potential.

Complexities of nadir-looking radiometric temperature measurements of plant canopies

Effective radiant temperatures (ERTs) of five wheat canopies in different stages of development were measured during morning and noon periods. The observed variability in nadir sensor response was quantitatively described as a function of canopy structure and the vertical temperature profile of canopy components. In many cases, the nadir sensor ERT was a poor measure of vegetation temperature due to effects of soil emissions. Strong vertical temperature profiles of vegetation components were also observed. The theory and measurements presented document that remote measurements of vegetation canopy temperatures cannot be made indiscriminately over large spatial regions without consideration of the underlying physical principles.

Plant canopy information extraction from composite scene reflectance of row crops

As an aid in the interpretation of remotely sensed data from row crops with incomplete canopies, a model was developed that allowed the calculation of the fractions of sunlit soil, shaded soil, sunlit vegetation, and shaded vegetation for each resolution element in a scan of a remote sensor for a given set of conditions (plant cover, plant height/width ratio, row spacing, row orientation, time of day, day of year, latitude, and size of resolution element). Using measured representative reflectances of the four surfaces, composite reflectances were calculated as a function of view angle. Also, representative temperatures for each surface were used to simulate composite temperatures viewed by an IR scanner. With composite reflectances and temperatures known as a function of view angle, ways were explored to extract plant cover and plant temperature data from the composite data.

Posterior iliopsoas muscle transfer in myelodysplasia

A Sharrard posterior iliopsoas muscle-transfer procedure was done in forty-two hips of twenty-four children with myelodysplasia. Folow-up ranged from twenty-nine months to approximately ten years. An over-all success rate of 50 per cent was achieved which included all hips operated on for potential and existing instability. The success rate for surgery in hips with an existing instability was 29.6 per cent. Factors predisposing to a poor result were: age more than five years old, dysplastic acetabulum (index more than 30 degrees), prior hip surgery, and inequality of limb length. This operation is recommended primarily for hips not previously operated on in children less than five years old who have a normal acetabular index. If the child is more than five years old or if acetabular dysplasia exists, reconstruction of the acetabulum should precede or accompany the tendon transfer for best results. Iliopsoas muscle transfer is unlikely to be successful if used as a salvage procedure.

Applications of a new instrument, the potentiophotometer

The Potentiophotometer is a new instrument for measuring the absorption characteristics of solutions. A brief description of its construction and theory of operation is presented, with illustrations of its use in the colorimetric quantitative analysis for inorganic phosphorus and total protein in serum. The potentiophotometric results correlate well (r = 0.97 to 0.98) with measurements made of the same solutions with either of two conventional spectrophotometers, the Gilford 300N and the Coleman Jr. II.

Applications of a new instrument, the potentiophotometer

The Potentiophotometer is a new instrument for measuring the absorption characteristics of solutions. A brief description of its construction and theory of operation is presented, with illustrations of its use in the colorimetric quantitative analysis for inorganic phosphorus and total protein in serum. The potentiophotometric results correlate well (r = 0.97 to 0.98) with measurements made of the same solutions with either of two conventional spectrophotometers, the Gilford 300N and the Coleman Jr. II.

Potentiophotometry

The present derivation relates, in terms of analytical chemical photometry, the theory of operation of an extremely simple instrument which embodies both the electrical analog solution to Beer's Law of Spectrophotometry and the multiplication of this solution by a constant, such that the voltage reading of the instrument is identical to the concentration of the light absorbing substance being measured. Because the raw output of the instrument is both linear and proportionable, calibration of the instrument is accomplished by appropriately setting and positioning the potential difference between two known standard solutions. The determination of the concentration of an unknown solution is then the direct reading of the voltage it generates in the system. This approach to measurement is called Potentiophotometry, because it is based on potentials generated from light.

Long-range observations with external aortic grafts

The late results of aortic aneurysms treated by external grafting are presented. This procedure consists of completely dissecting the involved aortic segment and suturing it in a well-fitted tubular Dacron prosthesis. The operation was carried out under the following circumstances: (a) Small fusiform aneurysm of the abdominal aorta. (b) Small and medium-sized aneurysms of the thoracic aorta. (c) Aneurysms unfavorably located in the very old and very debilitated. (d) Aneurysms involving the origin of the renal arteries. (e) Aneurysmatic dilatation of the aortic arch. Sixty-two patients were operated upon with this method with the follow-up period ranging from three months to seven years. There were no deaths during this period which could be directly related to either the aneurysm or the procedure itself.

Beneficial metabolic effects of methylprednisolone sodium succinate in acute myocardial ischemia

The metabolic and hemodynamic effects of methylprednisolone sodium succinate (40 mg/kg body weight) after acute myocardial ischemia were determined in 24 heparinized mongrel dogs. Myocardial ischemia was produced by ligation of the left anterior descending coronary artery. Catheters in the coronary sinus and the vein draining the left anterior descending coronary arterial area were used to collect blood samples from nonischemic and ischemic myocardium. Lactate, pyruvate, glucose, free fatty acids and oxygen were measured in arterial and venous blood from ischemic and nonischemic areas before and 3, 30 and 60 minutes after myocardial ischemia in animals with (Group II) and without (Group I) steroid treatment. In both Groups I and II glucose, lactate, free fatty acids, oxygen and coronary blood flow in nonischemic areas were not significantly changed, whereas glucose uptake in ischemic areas was significantly increased with myocardial ischemia and remained elevated. In Group I lactate uptake in ischemic areas became negative after coronary arterial ligation and remained so; in Group II, it increased after 30 (70%) and 60 (111%) minutes. Free fatty acid uptake in ischemic areas was reduced after myocardial ischemia in Group I, but in Group II it increased after 30 (224%) and 60 minutes (173%), and there was a concomitant increase in oxygen uptake. Pyruvate uptake in nonischemic areas decreased after 60 minutes in Group I, whereas it was reduced after 30 (68%) and 60 minutes (513%) in Group II. The changes were similar in ischemic myocardium. There were no significant changes in hemodynamic indexes. Coronary blood flow in ischemic areas decreased in Group I after myocardial ischemia and further after 30 and 60 minutes, but in Group II it increased after 30 (82%) and 60 minutes (53%). The data indicate that administration of methylprednisolone results in improved collateral blood flow into the infarcted area and a significantly improved metabolic response of ischemic myocardium. The glucocorticoid may also have a direct benefical effect on carbohydrate metabolism and cause the increased pyruvate neccesary to maintain the generation of energy-producing substrates. The results also suggest that methylprednisolone increases cell survival time and results in greater salvage of ischemic myocardium.