Structure, expression, and regulation of the major noncollagenous matrix proteins of bone.

The noncollagenous proteins (NCPs) that predominate the bone matrix have recently been the focus of intense investigation because of their potential influence on cell attachment, Ca2+ and hydroxyapatite binding, and the mineralization of bone tissue. With the advent of molecular biology, all of the major NCPs of bone have been cloned and their amino acid sequences completely determined. While each of the proteins has distinct structural properties, some proteins appear to be part of gene families. Examples include the small proteoglycans, decorin and biglycan, as well as the gamma carboxyglutamic acid proteins, such as matrix gla protein and osteocalcin (bone gla protein). Some of the NCPs that are clearly not members of any known gene family still share several common characteristics. One such example of this "convergent evolution" is bone sialoprotein and osteopontin. Both are highly posttranslationally modified glycoproteins that share the cell attachment amino acid sequence RGD (arginine-glycine-aspartic acid), which facilitates the attachment of bone cells in vitro, yet they are clearly not related genetically. Using cDNAs and antisera as probes, the precise temporal localization of NCP expression has been determined, and it has been shown that NCPs are produced in skeletal, and in most cases, nonskeletal tissue as well. This observation implies that the functions of the NCPs are not necessarily limited to bone tissue. Many of the promoters for these genes have been isolated and functional domains determined by a combination of chloramphenicol acetyltransferase assay, gel shift, and footprint analyses. The most extensively studied promoter in the NCP category is osteocalcin, whose sensitivity to 1,25-dihydroxycholecalciferol has been delineated in detail. Future studies on the individual and cooperative activities of the NCPs in bone are likely to involve site-directed mutagenesis of cloned DNA and a combination of in vitro and in vivo functional analyses.


Use of the Pavlik harness for hip displacements. When to abandon treatment.

Seven hundred twenty congenitally dislocated or subluxated hips in 550 patients less than one year old, treated with the Pavlik harness, were retrospectively reviewed. Overall, 11% of the hips proved irreducible by Pavlik harness treatment, 9% had dysplasia at the end of harness treatment, and 5% developed dysplasia by the age of two years two months (average). Fourteen percent of the hips positive for Ortolani's sign, 6% of the hips positive for Barlow's sign, and 2% of the congenitally subluxated hips required open or closed reduction followed by plaster hip spica immobilization. Avascular necrosis occurred in 0.7% of the hips treated with the Pavlik harness alone. Transient irritability with pain and limited motion of the hip occurred in 1% of the hips. The Pavlik harness is not appropriate for the larger child, most children older than eight months of age, the child in whom the examiner does not get an adequate sense of reduction, the hip that redislocates with the slightest adduction, and the hip that requires excessive flexion to maintain reduction. Pavlik harness treatment should be abandoned in favor of other methods if, after two to four weeks of use, abduction has not improved sufficiently to allow reduction, the hip has not reduced, or the hip remains unstable.


Mediators of bone resorption around implants.

An important cause of prosthetic loosening is bone resorption that results from the interaction of macrophages with implant surfaces and particulate debris. The mediators involved in this bone resorption were investigated in vitro. Medium conditioned by macrophages interacting with foreign materials was assayed for bone resorption stimulation and inhibition, and for prostaglandin E2 (PGE2). In some experiments, the medium was dialyzed, and in others indomethacin was added. Macrophages were found to release stimulators and inhibitors of bone resorption. The relative amount of these was variable. When macrophages interacted with foreign surfaces, their stimulatory effect was ten times their inhibitory effect. Further activation by phagocytosis caused a further 15-fold increase in stimulation, with no change in inhibition. It is probable that before macrophages encounter foreign materials their stimulatory and inhibitory effects are the same so that they do not cause net bone resorption. Important stimulatory and inhibitory mediators were not dialyzable and so were probably cytokines or possibly collagenase. Prostaglandins were neither important stimulators nor inhibitors. There was only enough PGE2 released to account for 2% of the bone resorption that was stimulated.


Evidence for eicosanoids within the reparative front in avascular necrosis of human femoral head.

Eicosanoids, including prostaglandins and leukotrienes, are important mediators of inflammation. To observe inflammation after necrosis, the histology and the changes of eicosanoid levels were compared in the subchondral cortex and spongy bone of femoral head of sixteen patients with Ficat III or IV idiopathic avascular necrosis (AVN). Neither inflammatory cells nor elevation of eicosanoid levels were observed in the necrotic subchondral cortex or osteochondral junction, whereas infiltration of lymphocytes and plasma cells, fibrosis, and fat emboli were present in the reparative front of necrotic spongy bone. Biochemical analysis in this region revealed significant increases of prostaglandin E2 (PGE2), 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), thromboxane B2 (TXB2), leukotriene B4 (LTB4), and LTC4. The increased eicosanoids due to initial necrosis become aggravating factors by increasing vascular permeability, which leads to marrow edema and intraosseous hypertension; it ultimately develops into a cycle of inflammation and AVN.


The conservative management of congenital dislocation of the hip after walking age.

Congenital dislocation of the hip (CDH) is a developmental disorder with a wide spectrum of clinical manifestations. Recent advances in imaging techniques have improved clinicians' understanding and early detection of CDH. Despite recent advances, some children remain undiagnosed until after they reach walking age.


Conservative treatment of congenital dislocation of the hip in the newborn and infant.

Five practical questions, concerning which hips should be treated, method of treatment, duration of treatment, treatment failure, and whether pretreatment traction is advised in congenitally dislocated hips, are discussed and answered. All hips positive for Ortolani's sign, hips positive for Barlow's sign, dislocated and irreducible hips, and hips that appear unstable by sonography should be treated. A large number of studies document the safety and effectiveness of early treatment in the Pavlik harness. Treatment may be stopped at six weeks in the newborn and three or four weeks after stability is achieved in children three or four months old at the time of initial treatment. Sonography is helpful in determining when to stop treatment. Hips that fail Pavlik harness treatment are at risk to fail with other types of treatment as well and require a cautious approach. Traction before treatment of congenital dislocation of the hip (CDH) may not be necessary. Recent studies have shown that safe reductions may be performed without preliminary traction.


The fetal acetabulum. A histomorphometric study of acetabular anteversion and femoral head coverage.

To study the development of the acetabulum in the early fetal period, 39 embryologic specimens were reviewed in detail. Histologic serial sections were made through 47 hips in the transverse plane. Measurements of acetabular anteversion and femoral head coverage revealed that both parameters depend on the exact level of sectioning. However, when measured at the level of the maximum diameter of the femoral head, they did not show significant variation through the embryonic and early fetal stages (six to 20 weeks). This is in contradistinction to the late fetal period. The hip does remain covered during this early fetal period. Congenital dislocation of the hip is not an early developmental condition. This accounts for the absence of any reports of hip dislocations in the first half of gestation.


Cause and prevention of osteochondritis in congenital dislocation of the hip.

All treatment modalities of congenital displacement of the hip (CDH) bear the risk of ischemic necrosis at the proximal femoral epiphysis. The causes of ischemic necrosis were investigated in a review of the literature and personal experience with CDH patients during the past 30 years. Compression of articular cartilage, caused by an increase in intraarticular pressure, has been implicated as the mechanism of osteochondritis. Muscle spasm, pressure on posterior circumflex vessels, and compromised pericephalic microcirculation in the newborn have been demonstrated to increase intraarticular pressure. The most dangerous causative factors include forced reduction under general anesthesia, spica cast immobilization of the hips in the Lorenz or Lange position, insufficient continuous prereduction traction, and splints or braces that are either too rigid or that force the hip into an extreme position. An intertrochanteric varus osteotomy can also lead to ischemic necrosis when performed at the time of reduction. Preventive measures include sufficient continuous traction, casting in a moderate position, and bracing that allows active movement. None of these measures constitute a guarantee against necrosis, but they will lessen the incidence and severity of involvement.


Neonatal screening for hip joint instability. Its clinical and economic relevance.

Effort to determine the efficacy of neonatal hip examination began in 1967. During the subsequent 23 years, there have been three analyses of the study's data: (1) a retrospective review reported in 1981, (2) a prospective examination in 1989, and (3) an economic evaluation in 1990. The retrospective review concluded that a neonatal hip screening program effectively screens for acetabular dysplasia, and early treatment seems to alter the outcome of congenital dislocation of the hip. The prospective examination, involving 62 newborns diagnosed as having dislocated or dislocatable hips, established that such cases can be effectively treated from birth with flexion/abduction splints monitored by routine clinical and follow-up examinations. An economic evaluation of the data demonstrated an economic benefit of more than $15,000 Cdn per 1000 infants screened. This study, through these three analyses, presents a compelling argument in favor of a routine, standardized neonatal hip examination.


Congenital hip dislocation. Long-range problems, residual signs, and symptoms after successful treatment.

In the treatment of congenital dislocation of the hip, reduction must be obtained and maintained to provide the proper stimulus for resumption of normal hip joint growth and development. Subluxation and avascular necrosis must be avoided, as degenerative joint disease is certain to occur. Acetabular dysplasia leads to degenerative joint disease with time, although no roentgenographic parameters are predictive. "Normal" hip joint anatomy may fail to develop, depending on the age of the patient at reduction and the growth potential of the acetabular cartilage. However, as normal anatomy as can be achieved should be restored at the age of maturity. This should provide the best possible mechanical environment to avoid exceeding the pressure tolerance level of the hip joint articular cartilage, thereby avoiding degenerative joint disease.


Etiologic factors in congenital displacement of the hip and myelodysplasia.

The two prime factors in the mechanism of intrauterine displacement of the hip are mesenchymal tissue abnormalities and mechanical stress placed on the fetal hip joint by the leg-folding mechanism. The somatic changes involve general laxity of the articular ligaments, attributable to either the physiologic effects of progesterone or a genetic trait consisting of familial joint laxity. The ligamentous laxity not only interferes with the folding mechanism of the fetal legs but also influences the torsional effect on the hip joints. This facilitates the displacement of the femoral head over the posterior rim of the acetabulum. The mechanical stress caused by the delay in leg folding also appears to play a role in a genetically determined occult form of myelodysplasia. Its prevalence has already been partially revealed by sensory evoked potential tests. Possibly, a more refined motor evoked potential test might help to explain a large percentage of the idiopathic cases. Thus, many of the etiologic factors in congenital hip displacement, previously considered to be caused by pre- and postnatal environmental influences, may well have genetic origins. These origins may be associated with varying degrees of underlying myelodysplasia. The relatively high incidence of firstborn affected, the ratio of female to male patients, the seasonal incidence of birth, and familial and racial prevalence may prove to be genetically predetermined.


Complete posterior sternoclavicular epiphyseal separation. A case report and review of the literature.

A review of the literature shows that fractures of the medial clavicular physis rarely occur. Fractures of the medial clavicular physis was diagnosed in a 14-year-old boy. Bony closure of this physis may not be complete until as late as 25 years of age. Complete fracture-separations of this physis, with posterior displacement into the mediastinum, should be included in the differential diagnosis of children and any young adult patients with an apparent posterior sternoclavicular dislocation.


Compensatory motion in the upper extremity after elbow arthrodesis.

Ten healthy male subjects were asked to complete a series of tasks that represent normal elbow function. They were then fitted with a custom adjustable brace that simulated elbow arthrodesis at 50 degrees, 70 degrees, 90 degrees, and 110 degrees flexion and asked to repeat the tasks. The 3 Space Isotrak system was used to measure shoulder motion; a triaxial wrist goniometer was used to measure wrist compensation; and all subjects were videotaped to qualitatively observe other compensatory motion. Unlike other joints, elbow arthrodesis at any angle results in a significant impairment, since the adjacent shoulder and wrist joints cannot compensate to allow completion of activities.


Hip flexion contracture in cerebral palsy. The association between clinical and radiologic measurement methods.

Hip flexion contracture was examined in 51 spastic cerebral palsy patients by three clinical methods and two radiologic methods. An extremely low association was found between the clinical and radiologic methods with no particular method, clinical or radiologic, showing a higher association. The method of clinical examination should be chosen by convenience. Radiologic measurements by the methods used did not add useful information.


Effects of explanation of treatment procedures on dental fear.

Dental fear has been described as anticipation anxiety. This study examined the effectiveness of providing pertinent details of treatment procedures to reduce the level of dental fear for dental checkups, prophylaxis, restoration and extraction in 306 fearful patients. Measurements of pre-treatment and post-treatment levels of fear showed a significant reduction in dental fear in all four procedures. Results showed that a better understanding of treatment processes reduced levels of dental fear in fearful patients.


Tobacco-related attitudes and counseling practices of Iowa dentists.

Evidence suggests that dentists' efforts to encourage their patients to stop tobacco use can significantly decrease tobacco-related morbidity and mortality. This study identified attitudes and counseling practices of 1116 Iowa dentists and compared results of a subgroup (N = 55) surveyed in both 1983 and 1989 to note changes in their tobacco-related attitudes and practices. Although only 9% of the dentists from the statewide survey felt counseling their patients on tobacco use was inappropriate, 56% reported they did not routinely ask their new patients about tobacco use. With some frequency 90% of the dentists discussed negative health effects of tobacco, whereas only 64% advised their smokers to quit. In addition, fewer than half made special efforts with pregnant patients or those at high risk for heart disease. The vast majority reported seldom if ever using intervention tools such as pamphlets or referral to cessation programs. Data from the subgroup surveyed in 1983 and 1989 indicated few substantial changes in attitudes and counseling practices. Substantial discrepancies exist between dentists' attitudes and counseling practices. Well-designed programs are needed to help dentists select and implement appropriate interventions.


Condition of toothbrushes in use: correlation with behavioral and socio-economic factors.

Toothbrushes and questionnaires from 94 adult dentate individuals were analyzed. More than 97% of respondents said they brushed their teeth at least once a day, while 48% used more than one toothbrush (such as one at home and another at work). Only 47% said they preferred a soft nylon bristle, while 41% preferred medium and 10% a hard nylon bristle. More than 73% of subjects said they used their brushes for 3 months or longer. Examination of collected brushes by both objective and subjective criteria revealed a wide variation in wear; however, the majority of brushes did not appear to be 'worn-out'. No significant correlation was found between objective wear-index and the educational level of the user, annual household income of the user, or reported time in use of the brush. A significant (p less than 0.01) correlation was found between brush wear-index and the ability of the user to judge toothbrush wear.


Effects of a two-phase oil-water mouthwash on halitosis.

Many oral microorganisms possess hydrophobic outer surfaces. A two-phase, oil-water mouthwash has, therefore, recently been developed to remove such oral microorganisms. The oil phase consists of olive oil and other essential oils. The aqueous phase includes cetylpyridinium chloride, which is a disinfectant that promotes the adhesion of microorganisms to oil droplets. This study determined the effects of this mouthwash on the production of volatile sulfide in vivo and in vitro. Neither rinsing with water nor brushing teeth decreased the concentration of sulfide in mouth air at 3.5 h after treatment. A reduction of only 30% of sulfide was observed when a commercial mouthwash was used. However, this study demonstrated that use of the two-phase mouthwash led to approximately 80% reduction of sulfide. Furthermore, volatile sulfide and 2-ketobutyrate productions from methionine in a saliva putrefaction system were completely inhibited by the two-phase mouthwash; and consumption of methionine was decreased by 65 percent. It is concluded that the two-phase mouthwash strongly inhibits the production of volatile sulfide.


Effectiveness of steam sterilization on the contents of sharps containers.

The purpose of this study was to evaluate the killing effect that treatment in gravity or high-vacuum steam autoclaves had on endospores present on strips or applied to dental needles within 10 types of small sharps containers. Spore strips containing Bacillus stearothermophilus endospores were used, while needles were soiled with an equal number of spores or with spores mixed with blood. Needles were tested capped and uncapped. Strips and needles were autoclaved in empty and 3/4 filled containers placed in several orientations (vents open or closed, upward or on-side). If sterilization was not accomplished within the initial period, additional exposure time was added up to a one hour maximum. Major findings for gravity autoclaves were: 1) strips and needles present in empty containers could, in most cases, be sterilized within 15 minutes when the vents were left open and the containers were placed on-side; 2) spore- and spore plus blood-soiled needles were more difficult to sterilize then were commercial spore strips; 3) capping of needles and the presence of blood did not decrease sterilization efficiency; 4) sterilization in the presence of fill material required additional exposure times and 5) larger containers (greater than 500 ml volume) were more difficult to sterilize than were the smaller (250 ml) ones. All type of open-vented, filled containers could be sterilized within 10 minutes in a high-vacuum autoclave.


Tongue indentations as an indicator of clenching.

This study examines the diagnostic efficacy of lateral tongue indentations as an indicator of clenching. A retrospective study of 113 patients (85 active and 28 recall) using radiographic indicators, excessive tooth mobility and self-report by the patient suggests that tongue indentations when present are indicators of clenching and warrant routine examination.


A survey on oral hygiene practices among Malaysian adults.

A survey on oral hygiene practices was conducted on 537 dentate adult patients aged 15 years and over. The aim of this study was to investigate the variation in dental behavior with regards to socio-demographic factors, namely age, sex, ethnicity, income, education and occupational status. Patients attending nine randomly selected government dental clinics were interviewed on their daily oral hygiene practices. The majority (89.7%) of the subjects reported that they brushed their teeth, 68% used toothpaste containing fluoride, but only 8.4% flossed their teeth. Generally the younger group had better oral hygiene habits. The higher the socioeconomic status of the adults, the better their toothcleaning practices. Awareness concerning dental floss was low regardless of all the socio-demographic variables. It was concluded that there is a need to improve the dental health practices of adults in Malaysia.


Maryland dentists' attitudes regarding tobacco issues.

Due to increased national interest in tobacco intervention roles for oral health professionals, a survey of Maryland dentists' attitudes toward tobacco issues was conducted. A convenience sample of 700 members of the Maryland State Dental Association was drawn from the total membership list (N = 2200). A 30% response rate was obtained. Subjects were mailed a twelve-item questionnaire that elicited primarily attitudinal information. Results revealed that 54.3% of the subjects never smoked, 39% formerly smoked and 6.1% currently smoke. Smoking behavior was associated with numerous attitudinal variables including dentistry's role in promoting tobacco-use cessation. Relatively few of the respondents were aware of federal initiatives regarding the oral health professions' roles in intervention. Less than half viewed tobacco-use cessation interventions as a practice builder, yet 82.1% believe cessation advice is the dentist's responsibility. Respondents' interest in obtaining free training in tobacco-use interventions was positive and was significantly related to several attitudinal variables. Dentists in Maryland appear to appreciate their role in tobacco-use interventions at both the clinical and community levels. However, they exhibit ambivalence regarding the economic value of office interventions and the need for formalized training. Maryland dentists also need to be apprised of federal initiatives concerning tobacco use interventions.


A six-week study comparing the efficacy of a rotary electric toothbrush with a conventional toothbrush.

The rotary electric toothbrush, Rota-dent, is often recommended and used as an alternative to the conventional toothbrush. The purpose of this short-term study was to evaluate the effectiveness of the Rota-dent on plaque removal and gingival health in comparison to a conventional toothbrush. Twenty-four subjects were divided into two groups. For 6 weeks one group used the Rota-dent, while the other group used a conventional (Oral-B 40) toothbrush. Plaque and gingival indexes were evaluated each week. Results indicated that the Löe and Silness Gingival Index scores improved significantly for both groups. There was a significant improvement in plaque removal as measured by Turesky modification of the Quigley-Hein Plaque Index for the Rota-dent group, while there were no significant differences in the Silness and Löe Plaque Index for either group. Thus, both devices had a positive effect on gingival health, and the Rota-dent removed plaque better than a conventional toothbrush as measured by one but not another plaque index.


High fruit consumption and the periodontal status of farm workers.

The results of a study on the periodontal health of orchard and vineyard workers on apple, grape, citrus and mixed-variety fruit farms are presented. Workers on grain farms were used as controls. The only significant differences in the diets of the different groups were the very large amounts of fresh fruits eaten by the fruit-farm workers. The CPITN index was used to record the periodontal status. Healthy periodontal sextants (code 0) were significantly less in the citrus group (P less than 0.05) compared to the other groups. However, this group also showed a significantly (p less than 0.05) lower prevalence of deep periodontal pockets than the other groups.


A prototype instrument combining laser Doppler flowmetry and reflection pulse oximetry.

A prototype instrument has been developed to combine the monitoring techniques of laser Doppler flowmetry and reflection pulse oximetry, both of which depend on laser light backscattered from the skin tissue. Simultaneous and continuous measurements of both microvascular blood flow and blood oxygen saturation were obtained from the same measurement site. Oximetry readings from the combined instrument were calibrated using a model system, and compared with those determined using a Nellcor N-100 transmission pulse oximeter in a limited clinical study: they showed a variability of +4% and read low by 5-10%.


The oral prophylaxis--survey II.

A survey of Wisconsin dentists was done to better understand what procedures dentists are including in their oral prophylaxis or soft-tissue management program. The goal of the survey was to develop data so that suggestions could be made to improve this service. When we compare this survey with the survey done four years ago, we see a decline in quality care, particularly in the time spent doing the oral prophylaxis. There was little or no improvement in recording of periodontal probing depths, sharpening of instruments, use of disclosing solution and the frequency of recall.


Blood reflux into cartridges for dental anesthesia: detection in residual solution.

The study examines blood reflux into cartridges under infiltration anesthesia. When imitation examination was carried out using Pontamine blue dye solution in 7 kinds of syringes using cartridges, dye reflux was observed in all of them. Dye reflux was observed in all but 1 of 4 kinds of cartridges on the market. The amounts of protein in residual anesthetic solution of cartridges after infiltration anesthesia were quantitatively measured by a dye binding method. Human hemoglobin was also measured by enzyme immunoassay (EIA). The detection rates of protein and human hemoglobin were 26.2% (85/324) and 24.2% (24/99), respectively. Study results show that blood reflux cannot be avoided in the cartridge system so reuse of residual anesthetic solution from cartridges should be prohibited as quickly as possible to avert risk of cross-infection of HB and AIDS virus.


The development of the low profile Liverpool shear transducer.

The development of a shear transducer, small enough to be worn comfortably under a normal foot, is described, along with a microcomputer controlled data logger. Walks up to 8 s can be recorded and the information downloaded to any IBM compatible computer. Software then allows easy analysis of the peak shear stresses. Calibration curves show the transducers to have a linear response up to 35N and preliminary data from the measurement of shear stresses under the normal foot, and their relationship to vertical pressures, is presented. A patent application (number 9109463.1) has been filed for the device in the United Kingdom.


Infrared emissivity of burn wounds.

Emissivities of burn wounds and tissue samples have been measured in the wavelength range 8-14 microns using a non-contact method. Emissivities of wound tissues studied were in the range 0.976-0.992, greater than those of intact skin by 0.01-0.03. This will result in underestimates of the difference in temperature between wounds and normal skin of 0.1-0.2 degrees C.


Measurement and prediction of drug solvent losses by evaporation from a jet nebuliser.

The evaporative losses of solvent (water) from a commercial jet nebuliser (Unineb, Unimed Ltd) were estimated and found to be approximately 14% of total nebuliser output. A simple analysis of the nebulisation process then enabled the amount of the drug colomycin released as potentially respirable aerosol to be predicted from measurements of the total nebulisation time. Good agreement was found between the predicted (P) and measured (M) values such that P = 1.07 M (r2 = 0.98). The analysis also indicates that the proportion of the drug released as aerosol will increase as nebulisation proceeds provided nebuliser output is continuous and that for a given initial mass of drug a larger amount of drug is released as an aerosol if the volume of administration used in the nebuliser is as large as possible.


Clinical evaluation of the effect of two types of dental floss on plaque and gingival health.

The aim of this clinical study was to evaluate two different flosses (an expanded PTFE-type floss and a nylon waxed floss) on the reduction of dental plaque, gingival health (MGI and BI), and patient preference when used in an oral hygiene program. Sixty adult subjects with gingival inflammation were assigned randomly to two groups. The control group were those subjects that used the nylon waxed floss and the test group were those subjects that used the PTFE-type floss. At 0, 2, 5, and 6 weeks, the patients were scored for plaque (PI), gingivitis (MGI), and interproximal bleeding sites (BI). The data were then analyzed statistically within each group and between both groups using Student t tests. It was found that there was no statistical difference between the two types of dental floss regarding PI, MGI, and BI. The only discrepancy was at the end of the second week, where the PTFE-type floss showed a significantly greater reduction in BI as compared to the nylon floss (p less than 0.01). Here the percent reduction of the PTFE-type floss was 56.1%, while the nylon waxed floss showed a percent reduction of only 39.1%. At the fifth week of examination the type of floss used was reversed for one week. This was done to determine patient preference. It was found that 74.5% of the study population preferred the PTFE-type floss while only 24.5% preferred the nylon waxed floss.


Effect of a twice daily 0.12% chlorhexidine rinse on the oral health of a geriatric population.

The inhibitory effect of a chlorhexidine rinse on gingival inflammation and plaque accumulation has been well documented. The purpose of this study was to determine whether a twice daily oral rinse with 0.12% chlorhexidine will resolve denture-associated inflammation in a geriatric population. Thirty-six subjects, average age 83 years, were randomly divided into two groups, active and control, and further stratified into three subgroups, removable partial dentures, complete overdentures and lacking a removable prosthesis. Gingival (Löe and Silness '63) and plaque (Silness and Löe '64) indexes were performed on teeth Nos 3, 9, 12, 19, 25 and 28 at baseline and at 60 days. The subjects, following baseline measurements, were required to rinse twice daily for 30 seconds with either a 15 ml solution of 0.12% chlorhexidine or a placebo and instructed to continue their normal oral hygiene routine. The data were statistically analyzed. When active and control groups were compared, either in total or within their stratified subdivisions, significant differences were observed (P less than 0.001). The active group had a 10.27% and 16.68% reduction in the gingival and plaque indexes, respectively, compared to insignificant changes in the control groups. It was concluded that although chlorhexidine proved effective in reducing inflammation and plaque scores, this reduction was not influenced by the type of prosthesis worn.


Accurate screening for abdominal aortic aneurysm.

In Birmingham a screening programme has been set up to detect abdominal aortic aneurysm in the male population between the ages of 65 and 75 years. The men to be screened are invited to their own general practitioners surgery and offered an abdominal ultrasound. The accuracy with which abnormalities can be detected is of crucial importance to a screening programme. Repeatability has been assessed for the single operator involved and is found to be +/- 1.3 mm. The accuracy of a single scan has been calculated by comparison with the measured diameter from a CT scan of the patient, taken subsequently. This comparison indicates that 95% of the differences between the two measurements can be expected to be less than 3.5 mm.


Single breath measurement of pulmonary blood flow in man: the causes of variability.

Theoretically, pulmonary blood flow can be measured by the uptake of a 'soluble' gas (e.g. freon-22) compared with an 'insoluble' gas (e.g. argon). As with all indirect methods, a number of uncertainties exist. Inhalation of a freon-22 and argon mixture (3.5%, 10%, 35% O2 balance N2) was made, with a subsequent, slow steady exhalation. The complete manoeuvre is termed the single breath technique (SBT). The repeatability of the SBT was assessed over four repeat measurements at rest, the mean difference between paired measurements lying in the range -0.09 to 0.04 l min-1, excluding the first trial measurements. Various features of the SBT were investigated to assess their influence on the reliability of the technique. It is shown: that the initial volume inhaled should be close to vital capacity; that a brief period of apnoea greater than 9 s following inhalation is necessary; that the subsequent exhalation should be about 10 l min-1; and that difficulties associated with recirculation of freon-22 are not encountered, presumably due to its wide distribution in body water. Under these highly controlled circumstances the technique is reliable.


High frequency eye tremor: reliability of measurement.

Recent reports suggest that high frequency eye tremor or ocular microtremor (OMT) may be a useful indicator of brainstem function. The method of record analysis, and in particular the amount of record subjected to such analysis, has varied widely. We have recorded OMT from 10 normal subjects. Using these records we have performed 42 distinct replication reliability studies. We suggest seven parameters of OMT (including overall frequency of tremor) which may be of value in comparing abnormal with normal records. For each parameter we have determined the optimal duration of the record to analyse and the reliability of such analysis. Our results suggest that at least 5 s of OMT should be analysed to yield an acceptable estimate of all seven parameters.


Inhibition of plaque accumulation under periodontal dressing by sustained-release varnish of chlorhexidine.

Slow-release varnish containing chlorhexidine was applied prior to the application of a periodontal dressing. The ability of the slow-release varnish to inhibit accumulation of dental plaque under the dressing was compared to a placebo varnish. Seven volunteers were fitted with periodontal dressing on the lower and upper jaws. One jaw was pre-coated with slow-release varnish containing chlorhexidine, while the other was coated with a placebo. A week later the dressings were removed and the plaque under the dressing was scored. Significantly less plaque was found on teeth pre-coated with the slow-release varnish containing chlorhexidine as compared to the control. An increase in the amount of gingival fluid was observed in both the control and experimental groups after removing the periodontal dressing.


A monitoring device for pressurised-air-driven diaphragm-based artificial heart assist devices.

A non-invasive device has been developed to monitor the diaphragm position and the blood flow in artificial heart assist devices equipped with a pressurised-air-driven diaphragm. Light scattering from the diaphragm is used as a mechanism for measuring. Information about the position of several points of the diaphragm can be obtained. The completely empty or filled situation can be detected and used for control purposes. Flow data can be extracted and bending characteristics of the diaphragm during operation can be studied.


Bacterial growth inhibition and short-term clinical efficacy of a vegetable oil-based mouthrinse: preliminary study.

Bacterial growth of a vegetable oil-based product was determined in vitro. Growth of Streptococcus mutans and Veillonella alcalescens was strongly inhibited for dilutions up to 50x. On the basis of these results, it was decided to evaluate the short-term, clinical efficacy of a 1:10 dilution of the concentrated product in water. Fifteen human volunteers employed this rinse twice-a-day during a six-day period. Planimetric plaque scores, as well as the plaque and gingival indexes according to Löe, were assessed at the beginning and end of this period. The efficacy of such a rinse, though less than of chlorhexidine-based products, turned out comparable to several other commercially available products with a reasonable potential in maintaining a low gingival index.


Assessment of oxygen transfer in membrane oxygenators during clinical cardiopulmonary bypass.

Although functional replacement of the heart and lungs by a pump and oxygenator is a widespread surgical procedure, no widely accepted technique for describing gas exchange in oxygenators exists. In this study, 8 types of commercially available membrane oxygenator (2 flat sheet membrane, 4 gas in hollow fibre membrane and 2 blood in hollow fibre membrane) have been studied during clinical cardiopulmonary bypass. O2 transfer increased with blood flow rate but the O2 transfer at a given blood flow was lower than that obtained by the manufacturers in laboratory studies. Overall O2 transfer coefficients were calculated from the ratio of O2 transfer rate to an O2 difference expressed either as an O2 partial pressure or an O2 concentration. Specific O2 transfer coefficients (overall coefficient divided by membrane area) were similar for oxygenators with a flat sheet or gas in hollow fibre membrane configuration. The two types of oxygenator with blood in hollow fibre membranes had significantly lower (P less than 0.01) specific O2 transfer coefficients. This study shows that oxygenator gas transfer characteristics can be studied in the clinical environment and that O2 transfer coefficients can be related to oxygenator design features.


Identification of chicken (Gallus domesticus) adipocyte plasma membrane and differentiation specific proteins using SDS-PAGE and western blotting.

1. Affinity-purified adipocyte membrane proteins were used to raise antisera in two sheep. 2. Using one of the antisera 15 proteins were identified as being adipocyte specific by comparison on Western blots of plasma membrane proteins from various tissues. 3. Of these 15 proteins eight appeared to be present only in mature adipocytes and not in the adipocyte precursor. 4. In the presence of guinea pig complement the two antisera raised were cytotoxic to adipocytes and their precursors. 5. Characterization and further study of these adipocyte differentiation specific proteins will provide valuable information about the process of adipocyte differentiation.


Antibacterial activity inducible in the haemolymph of the silkworm, Bombyx mori, by injection of formalin-treated Escherichia coli K-12 during the fifth larval instar and pharate adult development.

1. Antibacterial activity inducible in the haemolymph of the silkworm, Bombyx mori, by immunization, i.e. by injection of formalin-treated Escherichia coli (E. coli) K-12 during the fifth larval instar and pharate adult development that was reared aseptically on an artificial diet was determined by inhibition zone assay using the same bacterium as a test organism. 2. A peak of antibacterial activity was observed in each development stage; approximately 8 mm in diameter of a clear zone at days 3 or 4 in the fifth larval instar and approximately 5 mm at day 1 in the pharate adults. 3. Acid polyacrylamide gel electrophoresis of immunized haemolymph followed by overlay assay showed that an activity band was associated with two peptide bands that were similar to the cecropin-like peptides A and B that were reported in the silkworm (Morishima et al., 1988, Agri. Biol. Chem. 52, 929-934). Any other activity bands were not observed. No activity band was detectable from the haemolymph of non-immunized insects. 4. Fractionation of antibacterial peptides in immunized haemolymph on a CM-cellulose column resulted in separation of two groups of activity, both in the fifth instar larvae and in the pharate adults with a slight difference in elution conditions. 5. Duration of high antibacterial activity induced by a single immunization was approximately 12 hr in the fifth instar day 3 larvae and 48 hr in the day 2 pharate adults.


Regulation of intracellular protein degradation in the isolated perfused liver of the chicken (Gallus domesticus).

1. The effects of insulin, glucagon and a supply of exogenous amino acids on protein degradation have been studied in isolated perfused livers from growing chickens by measuring the rate of net valine release in the presence of cycloheximide. 2. Insulin inhibited protein degradation as did a supply of exogenous amino acids. 3. Addition of glucagon increased uric acid release from the livers but had no significant effect on protein degradation. 4. When the effects of the hormones and amino acid mixture are compared with published data for the rat it is evident that the action of glucagon differs in the two species.


Induction of antibacterial activity in the haemolymph of the silkworm, Bombyx mori, by injection of formalin-treated Escherichia coli K-12 in the anterior and posterior body part of the ligated larvae.

1. Induction of antibacterial activity was investigated in the ligated fifth instar larvae of the silkworm, Bombyx mori, by injection of formalin-treated Escherichia coli K-12 into the haemocoel in the anterior and in the posterior body part, followed by activity determination by inhibition zone assay of the haemolymph at 12 and 24 hr after immunization. 2. At 12 hr after immunization, high antibacterial activity, approximately 6.8-7.5 mm in the anterior body part and 4.5-6.4 mm in the posterior body part in diameter of a clear zone (2.0 mm for no activity) was detectable in day 3 larvae. This result was in good contrast to expression of lectin gene in the ligated flesh fly, Sarcophaga peregrena (Shiraishi and Natori, 1988, FEBS Lett. 232, 163-166), in which only the anterior part of insect responded to stimulus of injury. 3. Antibacterial activity at 24 hr after immunization in days 3 or 4 ligated larvae was lower than that at 12 hr; 4.0-4.5 mm of activity was observed in the anterior body part, and no activity was observed in day 3 ligated larvae in the posterior body part. 4. Acid polyacrylamide gel electrophoresis of the haemolymph of immunized insects followed by overlay assay showed that the size of antibacterial activity bands were similar between the haemolymph from 12 hr and from 24 hr, and between the anterior and the posterior body part. This result was contradictory to the observation of activity by inhibition zone assay. The activity bands were associated with peptides that were similar to cecropin-like peptides A and B in the silkworm.(ABSTRACT TRUNCATED AT 250 WORDS)


Purification and partial characterization of hyaluronidase from stonefish (Synanceja horrida) venom.

1. A marine hyaluronidase was purified 261-fold from the stonefish (Synanceja horrida) crude venom using Sephacryl S-200 HR and heparin affinity-gel chromatography. 2. Stonefish hyaluronidase has a pI of 9.2, a mol. wt of 62,000 and it was purified to a very high spec. act. of 1.6 x 10(6) NFU/mg protein. 3. It was heat sensitive and was inhibited by Cu2+, Hg2+ and heparin. 4. Stonefish hyaluronidase did not contain any haemorrhagic or lethal activity. 5. The N-terminal sequence of stonefish hyaluronidase has been determined to be A-P-S-X-D-E-G-N-K-K-A-D-N-L-L-V-K-K-I-N.


Structure of extracellular hemoglobin from the brine shrimp Artemia salina.

1. Hemoglobin from the brine shrimp Artemia salina, purified by ultracentrifugation and preparative gel electrophoresis in non-denaturing medium, gave in sodium dodecyl sulfate-polyacrylamide gel electrophoresis a single band corresponding to a polypeptide chain with Mr 150,000. 2. Crosslinking by glutardialdehyde resulted in the appearance of a band corresponding to a molecular mass twice that of a polypeptide chain. 3. Limited trypsinolysis gave eight proteolytic bands corresponding to submultiples 8/9-1/9 of a polypeptide chain. 4. We conclude that a molecule of Artemia hemoglobin is composed of two single polypeptide chain subunits and that each subunit consists of nine structural units roughly equal in size.


Oral immunization with Escherichia coli K-12 of the fifth instar larvae of the silkworm, Bombyx mori, reared on an artificial diet under completely aseptic conditions.

1. Effect of oral administration of live or formalin-treated Escherichia coli (E. coli) K-12 to the fifth instar, days 1 and 3 larvae of the silkworm, Bombyx mori, on induction of antibacterial activity in the haemolymph was investigated using the silkworms reared on an artificial diet under completely aseptic conditions. 2. When live E. coli was administered to the male day 1 larvae, low but significant antibacterial activity of 3.8 mm was detectable in the haemolymph of one individual at 48 hr after immunization. The proportion of the larvae to express antibacterial activity increased thereafter and at 120 hr after immunization, all three individuals showed antibacterial activity. In day 3 male larvae, activity was detectable at 48 and 72 hr after immunization. 3. When formalin-treated E. coli was orally administered to days 1 and 3 male larvae, no activity was detectable at any time post-immunization. 4. In the second experiment, when day 1 larvae, females and males were orally immunized with live E. coli, only females showed antibacterial activity in the haemolymph, beginning from 24 hr after immunization and up to 96 hr. 5. Removal of an antibiotic, chloramphenicol, from ingredients of an artificial diet was required for induction of antibacterial activity with oral administration of live E. coli. 6. When live E. coli that grows at pH 9.0 was selected and used for oral immunization, antibacterial activity was induced both in females and males at 72 hr after immunization and the activity was observed at 96 hr. 7. These results suggest that establishment of oral immunization with live E. coli in the silkworm larvae requires multiplication of E. coli in the midgut lumen and possibly its colonization on the luminal surface.


Urinary proteins in four rodent species.

1. Mean urinary protein concentration levels are significantly higher in male Peromyscus leucopus than females (98.4 and 72.4 mg/dl). 2. Only females showed a significant correlation between weight and urinary protein concentration (r = 0.75 vs r = 0.03). 3. In intraspecific sexual electrophoretic comparisons of P. leucopus and P. maniculatus non-denatured urinary protein, four and two common bands were identified, respectively. Males of both species showed an extra protein band. 4. Four common electrophoretically separable denatured urinary protein bands were observed between 14,200 and 116,000 mol. wt in male and female P. leucopus and female P. gossypinus. Three of the four major protein bands were also found in P. maniculatus. Male Reithrodontomys megalotis pattern showed none of the major bands.


Determination and developmental changes in carbonic anhydrase III in swine liver.

1. CA-III was measured by enzyme-immunoassay in the livers of male and female swine aged from the fetus to 5 years old. 2. No sexual dimorphism in porcine liver could be detected at 6 months, but stag showed twice as much as swine of the same age. 3. The concentration of CA-III in the liver increased during development up to 6 months of age, followed by decline due to senescence.


Purification and characterization of two forms of soluble NADH cytochrome b5 reductases from human erythrocytes.

1. Two forms of soluble NADH cytochrome b5 reductase were purified from human erythrocytes. Two distinct fractions both having the NADH cytochrome b5 reductase activity eluted from the second DEAE-cellulose column were further purified by ultrafiltration and 5'-ADP-agarose affinity chromatography. 2. The final preparations were purified 9070- and 4808-fold, respectively, over hemolysate. Both reductases exhibited identical electrophoretic patterns when subjected to SDS-PAGE and apparent monomer Mr of each reductase was determined to be 32,000 +/- 1300. 3. Vmax values of reductase II for the various electron acceptors, namely, 2,6-dichlorophenolindophenol, ferricyanide and cytochrome c through cytochrome b5 were found to be 1.9, 1.8 and 2 times higher than those of reductase I. 4. Some differences were noted for reductase I and reductase II fractions. Their elution profiles from a second DEAE-cellulose column were quite different and that suggested that reductase II is more acidic than reductase I. Reductase II was found to be more sensitive to heat treatment than reductase I.


Regulation of heme pathway in regenerating mouse liver.

1. delta-Aminolevulinic acid synthetase (ALA-S), rhodanese and microsomal heme oxygenase (MHO), were quantitated in Cl4C induced regenerating mouse liver. 2. Maximal hepatomegalia was observed at 48 hr after i.p. injection of a single dose of the toxin. 3. ALA-S activity decreased on day 2, and then significantly increased (50%) between days 3 and 7, returning afterwards to control values. 4. Cytoplasmic rhodanese, as well as MHO activities, exhibited a clear correlation as compared with the ALA-S activity profile. 5. Porphyrin biosynthesis from precursor delta-aminolevulinic acid (ALA) was significantly increased even after 15 days of intoxication. 6. Present results would indicate that Cl4C is acting in a dual fashion.


Purification and characterization of two chymotrypsin-like proteases from the pyloric caeca of rainbow trout (Oncorhynchus mykiss).

1. Two chymotrypsins, called chymotrypsin I and II, were purified from the pyloric caeca of rainbow trout, by (NH4)2SO4 fractionation, hydrophobic interaction chromatography (phenyl-Sepharose) and ion-exchange chromatography (DEAE-Sepharose). 2. The approximate molecular weights of chymotrypsin I and II were 28,200 (+/- 1200) and 28,800 (+/- 900), respectively, as determined by SDS-PAGE and their isoelectric points were about 5. 3. The pH optima of the enzymes were centered around nine, when assayed for succinyl-L-Ala-L-Ala-L-Pro-L-Phe-p-nitroanilide (Suc-AAPF-NA) as substrate and both enzymes were unstable at pH values below 5. 4. The amidase activity of both enzymes increased with temperature up to about 55 degrees C. Chymotrypsin I was found to be more heat stable than chymotrypsin II, an effect most likely explained by stronger calcium binding of the former. 5. The trout chymotrypsins were significantly more active than bovine alpha-chymotrypsin when assayed against Suc-AAPF-NA at 25 degrees C and casein at low temperatures (10-20 degrees C), indicating an adaptation of the activities of the trout chymotrypsins to the habitation temperatures of the fish.


Biosynthetic studies of marine lipids 36. The origin of common sterol side chains in eleven sponges using [3-3H]-squalene.

1. [3-3H]-Squalene was fed to 11 marine sponges containing a mixture of "common" sterol side chains. All of these sponges possess significant quantities of cholesterol, but their ability to biosynthesize it differs widely. 2. All the sponges possess significant quantities of delta 22 sterols, yet none of them was able to introduce the delta 22 double bond. 22-Dehydro-24-norcholesterol and 24-methyl-22-dehydro-27-norcholesterol side chains also originate from the diet. 3. These sponges biosynthesized between 40 and 80% of their sterols, a typical value being 70%. The remainder is derived from the diet or by modification of dietary sterols.


Measurement of O6-methylguanine-type adducts in DNA and O6-alkylguanine-DNA-alkyltransferase repair activity in normal and neoplastic human tissues.

1. Novel assays based on the use of the suicide repair enzyme O6-alkylguanine-DNA-alkyltransferase (AGT) to repair O6-alkylguanine-type adducts in DNA have been used for the analysis of extracts of human biopsy specimens of gastric mucosa, urinary bladder mucosa, colon and circulating lymphocytes. 2. Examination of these extracts revealed no detectable amounts of the precarcinogenic adduct O6-meG. 3. AGT measurements were the same among the normal and the autologous samples of all patients examined, which limits its prognostic value as a tumour marker. 4. AGT measurements from the cancer samples were much higher compared with the measurements of the other two groups which proves that AGT is just a marker of tumour burden. 5. Finally, AGT measurements from lymphocytes show that AGT from normal individuals have about the same value as that from patients suffering from cancer in urinary bladder mucosa and colon, but is much lower than that of patients with cancer in gastric mucosa.


Porcine thyroid cytosolic, latent alkaline ribonuclease: resistance to protein denaturants.

1. A ribonuclease isolated from porcine thyroid cytosol using phenol: sodium dodecylsulfate treatment was associated with RNA and identical to latent alkaline ribonuclease. 2. Distribution of activity between aqueous and phenolic phases depended on pH, RNA, and ribonuclease inhibitor. 3. The ribonuclease was totally resistant to urea, guanidinium: HCl, chloroform:isoamyl alcohol, ethanol, heating at 100 degrees C for 10 min or at 80 degrees C plus 100 mM NaCl. It was highly resistant to hydrolysis by proteinase K except in the presence of detergent. 4. The extreme stability and other properties of latent alkaline ribonuclease could be the result of its association with RNA.


Effects of several alcohols on glycosidase activities in rat liver and brain.

1. beta-D-Galactosidase, beta-D-glucuronidase and beta-NAc-D-glucosaminidase spec. acts from liver displayed statistically significant differences after treatments with certain alcohols. 2. No statistically significant difference was found for the kinetic parameters (Km and Vmax) of the indicated glycosidase activities. 3. beta-D-Glucuronidase and beta-NAc-D-glucosaminidase spec. acts from brain tissue showed statistically significant differences after treatments with certain alcohols. 4. beta-D-Glucuronidase and beta-NAc-D-glucosaminidase activities from liver showed a statistically significant decrease in the presence of in vitro ethanol. Tolerance effects were not observed.


Structure and possible function of heat-shock proteins in Falciparum malaria.

Like many prokaryotes and eukaryotes, the malaria parasite also synthesizes several stress proteins. Most widely studied stress proteins of this parasite are the heat-shock proteins (hsps). Their discovery in malaria is a gift of recombinant DNA technology. Five hsp genes from Plasmodium falciparum have been identified which are located on different chromosomes. Thus the inheritance and expression of hsp genes are independent of each other. They share a large amount of sequence homology at N-terminus with the hsps of other organisms. Their gene regulatory sequences and other elements, important for gene expression, are yet to be determined. The biological role of these proteins in malaria is not fully understood but it is possible that they provide protection to the parasite from various stresses encountered in the host. In this process hsps probably bind to the toxic molecules as well as damaged proteins to flush them out of the parasite. Their involvement in the stage-specific parasite transformation to increase the infectivity and virulence, as observed in other parasites, remains to be determined. Malarial hsps are antigenic in humans. This antigenicity could be attributed to the non-homologous sequences in the C-terminus region. The potential of one of them (pfhsp 70I) for a future malaria vaccine and immunodiagnostics requires re-evaluation of the data.


Developmental changes of lipogenic enzyme activities and lipogenesis in brown adipose tissue and liver of the rat.

1. Brown adipose tissue (BAT) and liver lipogenesis in vivo estimated by using 3H2O as tracer was very low and did not change significantly between 10 and 20 days after birth. Lipogenesis increased dramatically in both tissues by weaning at 20 days, peaking between 25 and 30 days of age. Since that time the rate of fatty acid synthesis in BAT decreased gradually to reach adult level after 2 months, whereas in the liver there was a sharp decrease of lipogenesis. 2. The activities of fatty acid synthase, citrate cleavage enzyme, malic enzyme and glucose 6-phosphate dehydrogenase essentially followed a similar course of developmental changes as lipogenesis. 3. In contrast to the enzymes listed above NADP-linked isocitrate dehydrogenase remained unaltered over the period studied, whereas lactate and malate dehydrogenases exhibited very high activity at 10 days after birth and from then decreased to reach adult level at the age of about 20 days. 4. The data obtained indicate that no substantial differences could be detected in the developmental pattern of lipogenesis and lipogenic enzyme activities between BAT and liver up to 30 days of age but after this time these processes were not co-ordinated in both tissues. Beyond this time the BAT was characterized by a much higher rate of lipogenesis than the liver. 5. The results are discussed in terms of the nutrient changes and the relationship between thermogenesis and lipogenesis in BAT.


A sulfated proteoglycan from the red alga Gracilaria verrucosa is a hemagglutinin.

1. A novel hemagglutinin was isolated from the red alga Gracilaria verrucosa and characterized as a sulfated proteoglycan with 92% carbohydrate content. 2. It is a dimer (MW 27,000 and MW 23,000); its molecular weight (MW) and isoelectric point are 49,000 and 3.8, respectively. 3. It agglutinates rabbit greater than horse greater than guinea pig greater than goose erythrocytes. 4. This activity is sensitive to heat, but insensitive to protease or periodate. It is not inhibited by simple sugars but by fetuin. 5. Since the periodate treatment of the rabbit erythrocyte lowers agglutination, this hemagglutinin is probably a lectin or a lectin-like molecule with complex saccharide specificity.


A comparison of highly unsaturated fatty acid levels in wild and farmed eels (Anguilla anguilla).

1. Absolute and relative amounts of eicosapentaneoic acid (EPA) and docohexaenoic acid (DHA) in muscle of eels from four different fish farms were compared with samples from wild eels from two different areas of northern Italy. 2. Farmed eels were richer in DHA and EPA than wild animals. 3. The addition of cod liver oil to the diet of farmed eels led to a significant accumulation of EPA and DHA, but no change in total lipid content. 4. The calculation of two indices related to highly unsaturated fatty acid (HUFA) content (FLQ = fish lipid quality; AI = aterogenic index), indicated the higher nutritional value of farmed vs wild fish. 5. We conclude that farmed eels are an adequate source of fish products for human nutrition and propose use of the above-mentioned indices as an effective means for assessing fish nutritional quality for populations at high risk of chronic degenerative disease.


Isoenzyme studies in one Brazilian and two Venezuelan strains of Schistosoma mansoni.

1. Enzyme polymorphism, analyzed by starch gel electrophoresis, was found to be zero for acid phosphatase, phosphoglucomutase, phosphoglucose isomerase, glucose 6-phosphate dehydrogenase, lactate dehydrogenase, malate dehydrogenase and malic enzyme, in one Brazilian and two Venezuelan strains of Schistosoma mansoni. 2. All loci studied were monomorphic within strains, but the isoenzymic patterns were, however, different among the strains. 3. Results suggest a drastic loss of the genetic variability usually found in natural populations.


Influence of hypoxanthine and other purines on the lecithin:cholesterol acyltransferase reaction in the plasma of rat and other species.

1. Esterification of radiolabelled cholesterol in the plasma of rat, mouse, pig, ox and, to a lesser extent, guinea pig was partially inhibited by hypoxanthine, xanthine and guanine; esterification in human plasma and in plasma from 12 other vertebrate species was unaffected by purines. 2. Esterification of endogenous cholesterol and the formation of lysolecithin in rat plasma were decreased in the presence of purines indicating that it was the lecithin:cholesterol acyltransferase (LCAT) reaction that was inhibited rather than the isotopic equilibration of labelled cholesterol with the endogenous substrate lipoproteins. 3. Maximum inhibition of the LCAT reaction in rat plasma occurred at 1.4 mM hypoxanthine or xanthine; inhibition was not dependent upon the concentration of LCAT or plasma lipoproteins but increased with the amount of lipoprotein depleted rat plasma (LDRP) present in the incubation mixture. 4. Partial inhibition of the LCAT reaction in rat or mouse plasma by purines had no significant effect on the fatty acyl composition of the cholesteryl esters (CE) formed by LCAT. 5. In the presence of heated rat plasma, LDRP or, to a lesser extent, rat high density lipoproteins (HDL) prepared from heated plasma, the LCAT reaction in human plasma was inhibited by hypoxanthine. 6. Rat HDL and LDRP prepared from plasma pre-incubated at 37 degrees C for 4 hr before heating increased and decreased, respectively, the inhibitory effect of hypoxanthine on human plasma LCAT compared with HDL and LDRP prepared from unincubated rat plasma.(ABSTRACT TRUNCATED AT 250 WORDS)


A soluble calcium-binding protein (SCBP) present in Drosophila melanogaster and Calliphora erythrocephala muscle cells.

1. Soluble calcium binding proteins (SCBP) were isolated from homogenates of whole flies, from the thorax and from muscles of Drosophila melanogaster and Calliphora erythrocephala. 2. Crude preparations were obtained by extraction at low ionic strength, acid and heat treatment. The Drosophila protein was purified by gel filtration, hydrophobic interaction and ion exchange chromatography. In contrast to calmodulin the Drosophila SCBP did not bind to phenyl-Sepharose in a Ca(2+)-dependent way. 3. Both the Drosophila and the Calliphora protein revealed identical properties. 4. The apparent molecular mass of the SCBP is 24 kDa. Separation in urea-PAGE demonstrated the existence of two isoforms. 5. The calcium-binding property was assured by a calcium dependent electrophoretic mobility shift and autoradiography of 45Ca(2+)-incubated Western blots. 6. The proteins are abundant in the thorax and were even detectable in crude extracts of various muscles (leg muscles and the extracoxal depressor). In contrast, in power muscles and in the thoracic ganglion the proteins could not be observed.


Distributions of polymorphisms among pathways of carbohydrate metabolism in the earthworm Eisenia fetida (Oligochaeta).

1. Activities and genetic banding patterns of 36 isozymes in carbohydrate metabolism were detected by spectrophotometry and starch-gel electrophoresis, respectively, in the earthworm Eisenia fetida. 2. Polymorphisms were not distributed randomly among metabolic pathways, activity levels, or gene copy numbers. 3. In glycolysis and the Krebs cycle, 16% of the loci were polymorphic and polymorphisms occurred only when multiple copies of the loci existed. 4. In other pathways, 45% of the loci were polymorphic and the distribution of polymorphisms was independent of gene copy number. 5. Polymorphisms may affect metabolic phenotypes and natural selection may have led to conserved biochemical activity in glycolysis and the Krebs cycle.


Purification and characterization of cathepsin H from hepatopancreas of carp Cyprinus carpio.

1. Cathepsin H was purified about 5400-fold from hepatopancreas of carp (Cyprinus carpio) by the method involving ammonium sulfate fractionation, and chromatography on S-Sepharose, DEAE-Sephacel, Ultrogel AcA54, Concanavalin A-Sepharose 4B and GPC on Protein-Pak 125. 2. The purified cathepsin H gave a single protein band on analytical-PAGE, but migrated as two bands of 27,000 and 23,000 mol. wt on SDS-PAGE. 3. Cathepsin H had a pH and temperature optimum of 6.5 and 45 degrees C using Arg-MCA as a substrate, respectively, and was activated by sulfhydryl compounds and inhibited by cysteine protease inhibitors and metal compounds having high reactivities at cysteine residue. 4. The carp hepatopancreas cathepsin H immunoreacted with the monospecific antibody against rat liver cathepsin H, and did not react with the antibodies against carp hepatopancreas cathepsins B and L by the method of immunoelectrophoretic blotting.


River buffalo (Bubalus bubalis L.) AA phenotype haemoglobins: characterization by immobiline polyacrylamide gel electrophoresis and high performance liquid chromatography and determination of the primary structure of the constitutive chains by mass spectrometry.

1. Polyacrylamide gel electrophoresis in ultra-narrow immobilized pH gradient shifted the "Hb fast" band of AA buffalo phenotype haemoglobin into two components which were named Hb1 and Hb3. 2. Urea/Triton electrophoresis and reversed-phase HPLC demonstrated that Hb1 and Hb3 differ in the presence of two structurally distinct alpha chains (alpha 1 and alpha 3), also suggesting that the alpha chains must differ for neutral amino acid substitution. 3. Extensive mass spectrometric analysis on several digests (FAB overlapping) meant to determine the complete sequence of the constituent chains. 4. Two amino acid replacements (Lys 18----His and Asn 116----His) were present in the beta chain with respect to the bovine (A phenotype) chain, whereas the alpha 1 and alpha 3 globins were found to contain four amino acid replacements compared to the bovine alpha, three of which were identical (Glu 23----Asp, Glu 71----Gly and Phe 117----Cys) and, notably, an insertion of Ala at position 123-124. 5. Furthermore, alpha 1 contains Phe at position 130 whereas alpha 3 contains Ser at position 132 (following the modified numbering as a consequence of the Ala insertion).


Characterization of the snake venoms from seven Brazilian species of Bothrops by FPLC anion-exchange chromatography.

1. The elution profiles and the caseinolytic, myotoxic, coagulant and hemorrhagic activities of the venoms of seven Bothrops species fractionated on a Mono-Q FPLC column were analyzed. 2. Each venom separated into 16-20 peaks, with good reproducibility and the activities were concentrated in virtually discrete regions of the chromatogram. 3. There is a considerable overlap of active proteins in the different species venoms and our results indicate that a venom pool with the species B. jararaca, B. jararacussu, B. moojeni, B. neuwiedi and B. atrox venoms would contain the major active proteins determined in the seven species.


Androgen metabolism in somatic and germinal tissues of the sea star Asterias vulgaris.

1. Cell-free homogenates of male and female pyloric caeca, body wall, testis and ovary were incubated with radiolabeled 3H-androstenedione. 2. Pyloric caeca had highest rates of androstenedione conversion. The predominant metabolites in the pyloric caeca were testosterone, 5 alpha-androstane-3 beta, 17 beta-diol and 5 beta-androstane-3 beta, 17 beta-diol. 3. In body wall, testicular and ovarian homogenates, androstenedione was converted primarily to testosterone and also to 5 alpha-androstanedione and epiandrosterone. 4. Qualitative and quantitative differences in androgen metabolism in somatic and germinal tissues may be related to tissue-specific regulation of cellular metabolism.


Isolation of an acute-phase phosphorylcholine-reactive pentraxin from channel catfish (Ictalurus punctatus).

1. Channel catfish (Ictalurus punctatus) serum contains a protein that precipitates pneumococcal C-polysaccharide (CPS) in a calcium-dependent fashion. 2. The serum titer of this protein follows an acute-phase pattern in catfish injected with turpentine. 3. A non-glycosylated, phosphorylcholine (PC)-reactive protein (PRP) with molecular mass ca 100 kDa, was isolated from channel catfish acute-phase sera by affinity chromatography on PC-Sepharose 4B. 4. Contaminating proteins with molecular masses ca 700 kDa and ca 20 kDa that co-eluted with PRP from PC-Sepharose appear to be aggregated and native low-molecular weight factors (LMFs), respectively. 5. Purified PRP has gamma mobility but in serum samples PRP has gamma-beta mobility. 6. Electron microscopy confirmed that PRP has planar, pentagonal symmetry. 7. The amino terminus of PRP is blocked, but based on comparison of amino-acid compositions channel catfish PRP is clearly similar to human CRP and is most like CRPs from the dogfish (Mustelus canis) and rainbow trout (Oncorhynchus mykiss).


Erythrocyte metabolism in two species of bats: common bent-wing bat (Miniopterus schreibersii) and red fruit bat (Pteropus scapulatus).

1. Metabolic intermediates, substrate utilization and enzyme activities were determined in the red blood cells of the common bent-wing bat and the red fruit bat. Standard haematological parameters and oxy-haemoglobin dissociation curves were also determined in both species. 2. The glycolytic rate as measured by lactate production was much higher for all substrates in the bent-wing bats. The activities of the glycolytic enzymes were also much higher in this species. 3. The standard haematological parameters were similar for the two species. The levels of 2,3-diphosphoglycerate (DPG) in the red cells of the fruit bat were nearly twice as high as those in the bent-wing bats. 4. The oxy-haemoglobin dissociation curve for the red fruit bat was located to the right of that for the bent-wing bat and both these curves were located to the right of that normally seen for human blood. 5. Both species of bat show blood characteristics well adapted to carrying the increased oxygen demands of flight.


Chelation affects the conformation, lability and aggregation of channel catfish (Ictalurus punctatus) phosphorylcholine-reactive protein (PRP).

1. Phosphorylcholine-reactive protein (PRP) affinity-purified from channel catfish (Ictalurus punctatus) serum on phosphorylcholine-Sepharose, eluted from Bio-Gel A-5M as a 94.6 +/- 2.4 kDa protein when the gel filtration column buffer (Tris-saline) contained 25mM ethylenediaminetetraacetic acid (EDTA). 2. PRP chelated with EDTA immediately after affinity purification and gel-filtered in Tris-saline-EDTA, eluted as a 75.5 +/- 2.67 kDa protein referred to as fast-PRP (F-PRP). 3. PRP and F-PRP were identical on SDS-PAGE. Both resolved as a broad band of protein (ca 86-100 kDa) on non-reducing gels or as a ca 100 kDa protein after reduction with 2-mercaptoethanol (2-ME). 4. After gel-filtration in Tris-saline-EDTA, nearly complete reduction of 100 kDa PRP was achieved on SDS-PAGE. However, the protein regained its resistance to reduction upon storage at -60 degrees C. 5. SDS-PAGE and native PAGE also revealed that during storage, PRP and F-PRP combined to form 3 different aggregates referred to as aggregated-PRP (aggPRP). These aggregates are readily dissociated in the presence of 2-ME, suggesting a covalent interaction between adjacent pentamers comprising decameric aggPRPs. 6. PRP, F-PRP, and aggPRP have similar amino acid compositions.


Subcellular fractionation evidence for a putative peroxisome-mitochondrion attachment in the liver of normal and genetically obese (ob/ob and db/db) mice.

1. Liver post-nuclear supernatants (PNS) from several mouse strains were fractionated by zonal centrifugation and fractions analysed by marker-enzyme estimations+electron microscopy. 2. Rate-dependent banding of PNS yielded peroxisome-enriched (PER) and mitochondrion-enriched (MER) regions. 3. Density-dependent banding of PER yielded peroxisomes (approximately 1.22 g/ml) well separated from mitochondria (approximately 1.8 g/ml). 4. Density-dependent banding of MER yielded peroxisomes that co-distributed with mitochondria and electron microscopy revealed close proximity of the two organelles. 5. Experiments demonstrated that co-distribution was not due to weak binding of proteins or to agglutination of organelles. 6. The results indicate in vivo attachment of some mitochondria and peroxisomes.


Association of monoamine oxidase and malate dehydrogenase with liver peroxisomes of genetically obese (ob/ob and db/db) mice.

1. Liver post-nuclear supernatants (PNS) from genetically obese (ob/ob and db/db), lean (+/?), and albino mice were fractionated by dual centrifugation in B-XIV zonal rotors and subcellular fractions were analysed by marker-enzyme estimations and by electron microscopy. 2. Rate-dependent banding of PNS yielded a peroxisome-enriched region (PER) well-separated from mitochondria. 3. Density-dependent banding of PER in ob/ob and db/db mice only, yielded purified peroxisomes which were associated with malate dehydrogenase (cytosolic) and monoamine oxidase. 4. Markers for the mitochondrial matrix, intermembrane space and inner membrane compartments were absent from the peroxisomes. 5. The experimental results are interpreted as indicating that peroxisomes of genetically obese mice are either altered so that protein import is imprecise or so that their attachment to mitochondria is more extensive.


Plasma lipoprotein cholesterol concentrations in the golden-mantled ground squirrel (Spermophilus lateralis): a comparison between pre-hibernators and hibernators.

1. The concentrations of total cholesterol (free cholesterol plus cholesteryl ester) in the plasma and in two lipoprotein fractions of golden-mantled ground squirrels (Spermophilus lateralis) were measured during pre-hibernation and compared to those values measured during hibernation. 2. Hibernating ground squirrels had significantly higher (P less than 0.005) very low density lipoprotein plus low density lipoprotein cholesterol (VLDL + LDL-C) concentrations than did pre-hibernating ground squirrels. 3. Hibernating squirrels additionally exhibited significantly higher (P less than 0.005) total plasma cholesterol concentration per high density lipoprotein cholesterol concentration (TPC/HDL-C) ratios than did pre-hibernating squirrels. 4. The significant differences in the lipoprotein cholesterol concentrations observed in this study suggest that lipoprotein metabolism in pre-hibernators was significantly different from that in hibernators and was a reflection of the marked biochemical and physiological adjustments these animals must undergo during their transition from pre-hibernation to hibernation.


Proline transport by tsetse fly Glossina morsitans flight muscle mitochondria.

1. Proline accumulation by tsetse fly Glossina morsitans flight muscle mitochondria was studied in vitro by the swelling technique and direct measurement of (U-14C) proline. 2. Proline transport was inhibited by the uncharged liposoluble -SH reagent, N-ethylmaleimide but not by ionic reagent, mersalyl, suggesting that the -SH groups involved in the transport of proline are located in a hydrophobic part of the membrane or on the matrix side of the membrane. 3. The kinetic study of proline accumulation revealed saturation kinetics and a high temperature dependence. It gave a Km of 85 microM and a Vmax of 962 pmol/min/mg protein and an activation energy (Ea) of 11 kcal/mol. 4. Certain other amino acids (L-valine, L-alanine, L-methionine, L-phenylalanine, L-tryptophan and L-hydroxyproline) significantly stimulated proline uptake. 5. These observations indicate that tsetse fly Glossina morsitans flight muscle mitochondria contain a proline transport mechanism.


On the origin of vertebrate-type steroids present in Locusta migratoria: do they originate from the food?

1. This study investigates the origin of vertebrate-type steroids which were reported to be present in Locusta migratoria: are the steroids synthesized by the locust or are they derived from the diet, i.e. grass and rolled oats? 2. It is unlikely that the steroids are synthesized by locust tissues. In vitro incubations of eleven different tissues with labeled pregnenolone or androstenedione did not result in androgen or estrogen synthesis respectively. 3. Steroid synthesis was also not detected when tissues were incubated in the presence of the early precursors cholesterol and isopentenyl pyrophosphate. 4. It is unlikely that the steroids are derived from the diet. Feeding experiments indicate that only low amounts of steroids are capable of crossing the gut-body barrier. 5. Injection of testosterone in the hemolymph also resulted in rapid excretion, instead of storage in tissues. 6. Moreover, radioimmunological measurements indicate that vertebrate-type steroids are absent in the food of locusts. 7. Specificity studies indicate that substances other than vertebrate-type steroids are detected by radioimmunoassay in locust tissue extracts. 8. Because vertebrate-type steroids are absent in locust tissues, it can be concluded that vertebrate-type steroids do not have a physiological function in Locusta.


Effect of castration and testosterone therapy on harderian gland protein patterns of the golden hamster (Mesocricetus auratus).

1. Sodium dodecyl sulphate 7-12% gradient polyacrylamide gel electrophoresis of male and female hamster Harderian gland whole homogenate shows a clear-cut sexual dimorphism, which consists of the presence of two male-specific glycoproteins (168 and 116 kDa) and two specific female proteins (210 and 190 kDa). 2. In the male, castration causes a significant decrease in the concentration of the two glycoprotein fractions. 3. Replacement therapy with testosterone propionate (T) restores the intact male pattern.


Comparative analysis of lipid composition in axenic strains of Blastocystis hominis.

1. Six axenic strains of Blastocystis hominis varied in content of lipids from 12 to 43 pg total lipid/cell. With all strains, phospholipid content was about 39% of total lipids. 2. Neutral lipid fractions of B. hominis were resolved into nine constituents, of which seven were identified tentatively. Sterol esters, principally esters of cholesterol, were the major neutral lipid constituent, accounting for 49-63% of the neutral lipids, and at least 30% of the total lipids. 3. Polar lipids were resolved into eleven constituents, of which nine were identified tentatively. Phosphatidylcholine was the major polar lipid constituent of all strains, accounting for 53-63% of the polar lipids, and about 22% of the total lipids.


Different proteins in the hemolymph sera from sarcomatous and healthy soft shell clams, Mya arenaria L.

1. Serum proteins showed quantitative and qualitative differences between sarcomatous and healthy soft shell clams, Mya arenaria L. 2. Total protein concentration was significantly higher in the serum of sarcomatous clams than of healthy clams. 3. According to SDS-PAGE, more serum proteins with more variability distinguished sarcomatous clams from healthy ones. 4. Sarcomatous clams had unique serum proteins of M(r)23,000, 45,000 and 54,000. Healthy clams had unique serum proteins of M(r) 24,000, 103,000 and 105,000. 5. During disease progression, sarcoma-specific proteins appeared while normal proteins disappeared. 6. We propose that some sarcoma-associated proteins may have tumor promoting and/or cytotoxic functions and that some normal proteins which disappear during disease progression may be involved in the humoral defense system.


Proteinases of the medicinal leech, Hirudo medicinalis: purification and partial characterization of three enzymes from the digestive tract.

1. Three different proteinases were isolated from intestinal extracts of Hirudo. 2. The action on synthetic substrates and the effect of various inhibitors indicate that one is a trypsin-like enzyme whereas the other two are chymotryptic. 3. This was confirmed by analysing the degradation of the insulin B-chain. 4. The relative molecular masses of all enzymes are approximately 35,000 and the isoelectric points 9.03, 9.12 and 9.41, respectively. 5. The specific activities assayed with SAPPNA are very high in comparison with proteinases of other animals.


Regulation of oxidative activity and delta psi of liver mitochondria of active and hibernating gophers. The role of phospholipase A2.

1. In the present work the initially lowered oxidase activity of liver mitochondria of hibernating gophers is shown to increase upon Ca(2+)-loading, after freezing-thawing repeated three times and after swelling in a medium containing potassium acetate as well as in a hypotonic sucrose medium. 2. In all cases the inhibition of phospholipase A2 hindered the increase of the oxidase activity of mitochondria. 3. Mitochondria of hibernating gophers have a lowered delta psi in comparison with active animals, which is restored in the hypotonic medium.


The heptadecanoic fatty aldehyde--one of the main aldehydes of the far-eastern Bryozoa.

1. The relative content of 16:0, 17:0 and 18:0 fatty aldehydes in the lipids of eight species of the far-eastern Bryozoa was studied. 2. Heptadecanoic aldehyde is one of the main aldehydes in the seven species investigated comprising about 30% of the sum of these main bryozoan aldehydes. 3. We suggest the unusually high relative heptadecanoic aldehyde content in the lipids of Bryozoa may be helpful in settling some problems concerning their system.


Spatial representations of words and nonwords.

The first two experiments investigated whether the representations of words, besides being unitary, are also spatial in nature. Subjects were required to search for target letters in either five-letter words or five-letter nonwords. They were instructed to press the right-side key for one target and the left-side key for the other target. The center item of the letter string was always at fixation. Targets appeared one at a time, located at the second (left side) or the fourth (right side) position within the letter string. The results showed that: a) responses to targets within words were faster than responses to targets within nonwords (the word-superiority effect); b) responses to compatible stimulus-response pairings were faster than responses to incompatible stimulus-response pairings (the spatial compatibility, or, more precisely, the Simon effect); and c) in Experiment 2, left-side targets were responded to faster than right-side targets within nonwords (the left-right scanning effect). It was concluded that representations of both words and nonwords are spatial in nature. Experiment 3 was aimed at testing whether the spatial layout of the representations of words is always along the left-right horizontal dimension, regardless of the topographic transformation of the stimulus. The same words and nonwords used in the previous experiments were shown vertically and the subjects were required to make left-right discriminative responses to upper and lower target letters. The results showed the word-superiority effect but no spatial compatibility effects. It was concluded that the representation of a vertically presented word is vertically arranged.


"Fatal familial insomnia": neuropsychological study of a disease with thalamic degeneration.

Fatal Familial Insomnia (FFI) is an inherited disease characterized clinically by sleep, autonomic and motor disturbances and pathologically by marked atrophy of the anterior and dorsomedial nuclei of the thalamus. The neuropsychological study of three cases of FFI showed: (1) a progressive disturbance of attention and vigilance, (2) a memory deficit with lability of mnesic traces and difficulty in manipulation and ordering of events, suggesting an alteration of working memory and (3) a deficit of frontal abilities with impairment in planning and prevision of events but preservation of general intelligence.


Everyday memory after unilateral temporal lobectomy or amygdalo-hippocampectomy.

Patients who had undergone unilateral temporal lobe surgery (right or left temporal lobectomy or amygdalo-hippocampectomy) for intractable temporal lobe epilepsy, and normal control subjects, completed two questionnaires about everyday memory, the Subjective Memory Questionnaire (SMQ) and the Everyday Memory Questionnaire (EMQ). Relatives/close friends completed suitably adapted versions of these questionnaires about the patient. Patients who had undergone right and left temporal lobectomy rated themselves, and were rated by relatives/friends as having worse memories than controls on both the SMQ and EMQ. Individual items on both questionnaires differentiated between the memory abilities of the five groups. Age at surgery was correlated with one measure of everyday memory for the right temporal lobectomy group, and seizure frequency was correlated with memory performance for the amygdalo-hippocampectomy groups. Issues concerning validity and accuracy of rating memory lapses are discussed.


Partial remission of hemiplegia and somatoparaphrenia through vestibular stimulation in a case of unilateral neglect.

In a case of long lasting severe neglect resulting from a large right parieto-temporo-occipital infarct, vestibular stimulation produced a temporary reduction of the motor deficit and disappearance of the somatoparaphrenic delusion, in addition to the already reported improvement of extrapersonal and personal neglect and anosognosia. These data open new perspectives in the understanding of the neglect syndrome and of functional involvement of the parietal lobe in space representation.


Linguistic perseveration in dominant-side intracarotid amobarbital tests.

148 patients with medically intractable complex-partial seizures received bilateral intracarotid amobarbital tests. In 21 patients (14.2%), there were inappropriate responses (intrusions: N = 10; perseverations: N = 11) to a series repetition task (counting backwards) given immediately before amobarbital injection. Five cases from the perseveration subgroup are discussed in detail. In these patients, linguistic perseveration occurred with left-sided amobarbital injection, although they were all found to have left hemispheric speech dominance according to language testing during the amobarbital procedure. It is argued that these perseverations are best explained as a right hemispheric continuation of a speech motor program previously initiated by the left hemisphere.


Proper name anomia.

Following a left thalamic infarct, a patient showed a marked impairment in retrieving person proper names in response to faces and to verbal description, despite being able to provide precise information about the persons he could not name and to point to their photograph when the name was provided by the examiner. The patient was also impaired in generating proper names, but could easily retrieve common names as well as geographical names and names of monuments. It is hypothesized that the arbitrary nature of the link between proper names and their referents makes access of phonological forms from the semantic store particularly labile. In agreement with this interpretation is the patient's inability to recall telephone numbers and to learn semantically arbitrary paired associates.


Verbal fluency and positron emission tomographic mapping of regional cerebral glucose metabolism.

Impairment in verbal fluency (VF) has been a consistently reported clinical feature of focal cerebral deficits in frontal and temporal regions. More recent behavioral activation studies with healthy control subjects using positron emission tomography (PET), however, have noted a negative correlation between performance on verbal fluency tasks and regional cortical activity. To see if this negative relationship extends to steady-state non-activation PET measures, thirty-three healthy adults were given a VF task within a day of their 18F-2-fluoro-2-deoxy-D-glucose PET scan. VF was found to correlate positively with left temporal cortical region metabolic activity but to correlate negatively with right and left frontal activity. VF was not correlated significantly with right temporal cortical metabolic activity. Some previous studies with normals using behavioral activation paradigms and PET have reported negative correlations between metabolic activity and cognitive performance similar to that reported here. An explanation for the disparate relationships that were observed between frontal and temporal brain areas and VF might be found in the mediation of different task demands by these separate locations, i.e., task planning and/or initiation by frontal regions and verbal memory by the left temporal area.


Failure of metacontrol: breakdown in behavioural unity after lesion of the corpus callosum and inferomedial frontal lobes.

A right-handed man suffered aneurysmal haemorrhage with lesions of the genu and body of the corpus callosum and the inferomedial frontal lobes bilaterally (right more than left). He exhibited remarkable breakdown in behavioural unity characterized by conflict between the two sides of the body, actions inconsistent with verbalizations, and internal conflict over control of the left hand. A major feature of the deficit was its temporal variability. This is interpreted as reflecting intermittent failure of metacontrol processes, which are neural mechanisms for maintaining behavioural unity. Medial frontal structures and their interconnections through the corpus callosum appear particularly important in the maintenance of metacontrol.


Impaired visual perceptual categorization in right brain-damaged patients: failure to replicate.

The association of both Perceptual Categorization (PC) and Semantic Categorization (SC) with sensory performance was investigated. 28 RBD, 27 LBD and 21 non-brain-damaged subjects were tested with the PC and SC tasks described by Warrington and Taylor (1978) and with 6 sensory tasks. PC was related to sensory performance in RBD but not in LBD patients. SC was only marginally associated with sensory ability in both lesion groups. RBD and LBD patients differed significantly at neither PC nor at SC. Thus the dissociation between PC and SC, described by Warrington and Taylor (1978) was not replicated. Moreover, PC and SC were significantly correlated in both RBD and LBD patients. This suggests that the serial organization of PC and SC is questionable. It is concluded that the associations we obtained between SC, PC and sensory performance are likely to be functional. The contribution of a cognitive factor ("abstraction") to PC and SC is discussed.


Variations in lateralized processing among right-handers: effects on patterns of cognitive performance.

Two experiments investigated whether individual differences among right-handers in patterns of lateralized processing were related to level of performance on a variety of cognitive tasks presented under non-tachistoscopic conditions. Subjects were divided into two groups of individuals, those who characteristically have greater than average right-hemisphere involvement in functioning and those who characteristically have greater than average left-hemisphere involvement. In the first experiment we examined whether characteristic individual differences in hemispheric involvement could predict performance on a facial memory task. The group with relatively greater right-hemisphere involvement had better recognition memory than the group with relatively greater left-hemisphere involvement. In the second experiment, we examined whether individual differences in hemispheric involvement could predict performance on a larger set of cognitive tasks. The groups were administered two tasks selected to evaluate left-hemisphere function and two selected to evaluate right-hemisphere function. The results indicated that the groups differed in their profile of cognitive performance. Individuals with greater than average right-hemisphere involvement in processing tended to perform better on tasks indexing right-hemisphere function than on tasks indexing left-hemisphere function, whereas the opposite was true of individuals with greater than average left-hemisphere involvement. Collectively, the results of these two experiments indicate that individual differences in lateralized performance have important implications for individual differences in patterns of cognitive ability.


Flash and pattern reversal visual evoked responses in normal and demented elderly.

P1 and P2 components of visual evoked responses (VERs) to flash stimuli were compared between patients diagnosed as suffering from Senile Dementia of the Alzheimer Type (AD) and elderly controls. Additionally the P100 component of the VER to pattern reversal stimuli at high and low contrast and using large and small check patterns was compared. Significant differences between moderate AD patients and the normal elderly were found for the P2 component of the flash stimulus and for the P100 component of the high spatial frequency pattern reversal stimuli at low contrast. These findings suggest a deficit in primary visual processing and a selective deficit in secondary visual processing in moderate cases of dementia. This indicates that visual processing capacities of AD patients decline as the disease progresses in line with the continual degeneration of neuronal populations involved with vision.


Pure word deafness due to left hemisphere damage.

We report the case of a 55 year-old right-handed man who presented with a long lasting pure word deafness following left thalamic bleeding. There was no sign of aphasia. The auditory deficit was specific for language, while recognition of music and environmental sounds was normal. CT, MRI and PET examinations showed that the lesion was anatomically and functionally confined to the left cerebral hemisphere, mainly the white matter of the temporal and parietal lobes. Wernicke's area was largely preserved. It is proposed that pure word deafness was consequent to the isolation of Wernicke's area from incoming auditory information due to the interruption both of the association fibers from the right auditory area traveling across the corpus callosum and of the left auditory radiations.


Improvement of renal preservation by adding lidoflazine to University of Wisconsin solution. An experimental study in the rat.

The purpose of this study was to investigate the possibility of improving the organ preservation properties of the University of Wisconsin (UW) solution by adding the calcium entry blocker lidoflazine. We also investigated the possibility of decreasing the cold ischemia and reperfusion damage by pretreatment with lidoflazine of the donor and/or recipient. The protective effects of lidoflazine treatment were estimated by measuring the amount of trapped erythrocytes in the rat renal medulla after 48 h of cold storage, subsequent transplantation, and 20 min of reperfusion. Lidoflazine (20 mg/liter) added to the UW solution decreased the amount of erythrocyte trapping from 14.8 +/- 3.1% in controls to 8.6 +/- 1.7% (P less than 0.01). The flow rate of the flush-out solution during the harvesting procedure was also significantly (P less than 0.01) increased when lidoflazine was included in the UW solution (1.10 +/- 0.21 ml/min vs 0.75 +/- 0.22 ml/min). Administration of lidoflazine (0.28 mg/kg body wt) to the donor and/or the recipient did not further reduce the postischemia/reperfusion damage as estimated by the degree of erythrocyte trapping. In conclusion, the results indicate that the preservation properties of the UW solution can be significantly improved by adding lidoflazine to the solution.


Microvascular changes of the liver preserved in UW solution. Pathological and immunohistochemical examination.

Rat livers preserved in University of Wisconsin (UW) solution for 24 h were compared with those preserved in Euro-Collins (EC) solution before and after liver transplantation using an immunohistochemical method. Tissue ATP and total tissue adenine nucleotide (TAN) were measured using HPLC. The levels of TAN in the UW group or the EC group were significantly low compared with the control group (no preservation) after 24-h storage. In the EC group, the levels of tissue adenine nucleotides (TAN) decreased 1 h after reperfusion and never reached control levels. In the UW group, the levels of TAN increased a little 1 h after reperfusion and increased more 3 h after reperfusion. After 24-h preservation, the expression of factor VIII-related antigen (FRA) in endothelial cells of central veins was weak in the EC group; in the UW group, FRA was clearly detected in these cells. After reperfusion, although severe endothelial cell damage to the central veins and numerous FRA-positive substances were observed in EC group, endothelial cells of central veins retained their normal structure and FRA-positive substances were rarely noted in the UW group. In both groups, no endothelial changes were detected in portal veins. From these results, it is concluded that UW solution prevents endothelial cell damage and microcirculatory injury in zone III during the preservation period resulting in prevention of initial graft nonfunction. Also, measurement of the TAN level after reperfusion is useful to predict the function of the graft.