Coexistence of reef organisms in the Abrolhos Archipelago, Brazil

The first study on coexistence of reef benthic organisms in Brazilian coral reefs was done in three localities of the Abrolhos Archipelago. Organisms were recorded in concentric circle samples (10 and 20 cm in diameter) randomly laid on transects. Type and frequency of "coexistence events" between pairs of organisms were determined. Most frequent organisms (massive and branched coralline algae, Favia gravida, and Agaricia agaricites) also had many significant positive coexistence events. These results might be related to the abundances of these organisms. The most frequent coral (Siderastrea stellata), however, exhibited only a few significant coexistence events (9% of 32 tests). Since the great majority of events were positive, and since there was high variation in the species/groups involved in significant events in different localities, benthic communities of Abrolhos Archipelago may well be structured primarily by abiotic rather than biotic factors.

Alcohol dependence among Alaska Natives entering alcoholism treatment: a gender comparison

OBJECTIVE

An ongoing study of phenotypes of alcohol dependence among Alaska Natives provides an opportunity to investigate the nature and patterns of alcohol problems among Alaska Native men and women admitted to treatment in three residential programs in Anchorage, Alaska.

METHOD

A comprehensive, standardized clinical assessment (including the SSAGA-I diagnostic interview, family history information, personality traits and cognitive functioning) of consecutive admissions to each of the three programs is being undertaken by trained interviewers. To date, 200 (103 male) subjects have been assessed. The mean (+/- SD) age of the sample is 32+/-8.5 years old. The development of alcohol problems, the psychological and physical consequences of chronic drinking, the flushing response, withdrawal symptoms and comorbid lifetime psychiatric conditions were examined.

RESULTS

The sample was characterized by an early onset of drinking and an acute exacerbation and clustering of drinking problems during late adolescence, followed by the development of severe alcohol dependence. A high lifetime prevalence of DSM-III-R major depressive disorder was found, typically complicated by chronic drinking. The rates of other substance dependencies were relatively low, except for cannabis and cocaine dependence among female subjects.

CONCLUSIONS

This sample of treatment-seeking Alaska Natives was found to have an early onset and severe form of DSM-III-R alcohol dependence, with few gender differences noted. While the prevalence of alcohol abuse and alcohol dependence among Native American populations has been reported to be quite high, the onset and patterning of symptoms among this sample of treated Alaska Natives has revealed more similarities with treated alcoholics from the majority population than important differences specific to Alaska Natives.

Can minimum separation criteria ensure electromagnetic compatibility in hospitals? An experimental study

Electromagnetic interference (EMI) from radiofrequency (RF) sources can cause medical device malfunction. It has been proposed that such EMI be minimized by only operating sources of given RF powers when sufficiently separated from medical devices of given immunities. Such minimum separation criteria are estimated assuming free-space propagation, which is only valid in the ideal case. Yet proposed medical device EMC standards will require that minimum-separation criteria be listed in equipment manuals accompanying all new medical devices. It is essential that the practical utility of such minimum-separation criteria be evaluated. Fields due to an 800-MHz-type cellphone were measured in various rooms and corridors within an urban hospital, having both new (gyprock) and old (clay-block) wings. Data obtained from a calibrated antenna attached to a spectrum analyzer were repeatedly measured and averaged. Results were compared to those predicted by free-space propagation. Free-space predictions tended to overestimate measured fields in gyprock rooms and along corridors of both gyprock and clay-block construction. However, the free-space model tended to underestimate field levels predicted in clay-block rooms and in below-ground corridors. Usage of separation criteria to ensure EMC appeared useful in gyprock rooms and hospital corridors, but less so in rooms with clay-block walls or in below-ground sections of the hospital. This suggested that the latter regions should be considered as being special zones where side-by-side operation of RF sources and medical devices would require more conservative management (e.g., restriction or special approval of particular source or medical device).

ADH and ALDH polymorphisms among Alaska Natives entering treatment for alcoholism

The alcohol dehydrogenase (ADHs) and aldehyde dehydrogenases (ALDHs) involved in alcohol metabolism are polymorphic. Different alleles encode subunits of the enzymes that are related to differences in alcohol metabolism with different ethnic groups. This study examined the allele frequencies at the ADH1, ADH2, ADH3 and ALDH2 loci in Alaska Natives entering treatment for alcoholism to determine if allele frequencies at these loci differ among five distinct Alaska Native groups: Yupik and Inupiat Eskimos, Athabascan, Tlingit and Aleut. It was found that all persons were homozygous for the ADH1*1, ADH2*1 and ALDH2*1 alleles. Variations, however, were found for the allele distribution of the ADH3 genotype. Comparison with a general population sample found no differences in allele distributions for ADHs and ALDH2*1, but differences were found when comparisons were made with four Asian Groups. The study's findings suggest that the Alaska Natives are not protected from the risk of alcoholism in the same way that Asians who possess the ALDH2*2 genotype are considered to have a negative risk factor. Nor, does there appear to be any generalized differences between Alaska Native alcoholics and members of the general population with respect to the ALDH and ADH polymorphisms studied herein.

Drinking and drinking-related problems among Alaska natives

Alcohol use has adversely affected many aspects of the Alaska Native community. To a large extent, overcoming the problem of alcohol abuse may require that Alaska Natives craft individual and community solutions to detrimental health, social, and economic conditions and instill new patterns of living that inhibit alcohol abuse. An example of this approach is the Alaska Federation of Natives' "sobriety movement," a grassroots campaign to promote sobriety that emphasizes traditional values and lifestyles. The use of "healing" or other traditional methods may help Alaska Natives both recover from the trauma of decades of cultural conflict and address alcohol problems in their communities.

Long-term effects of neuromuscular rehabilitation of chronic facial paralysis

Although chronic facial dysfunction can be improved with neuromuscular biofeedback therapy, it is uncertain whether this improvement is maintained after such therapy ends, or whether post-therapy, home exercise programs optimize this improvement. We aimed to clarify these issues. Post-therapy facial function, in 38 previously treated patients, was blindly assessed using the House grading system, 1 to 41 months after ending therapy. Results were compared with pre-therapy function. It was found that post-therapy function was better than pre-therapy function in most patients (40%), it was worse in some (26%), and was unchanged in the rest. This surprising result occurred because, although most patients who recently stopped therapy (1 to 6 mo) had improved significantly, the longer other patients were out of therapy, the more they had tended to deteriorate, particularly those who had been practicing. Results suggested that unsupervised, post-therapy, home exercise programs may be detrimental, and that new post-therapy programs may be required to maintain the benefits of regular therapy.

"Silent" malfunction of a critical-care device caused by electromagnetic interference

Although there have been many previous reports of serious medical device malfunctions caused by electromagnetic interference (EMI), it is not widely recognized that many such malfunctions were "silent," having occurred without triggering a device alarm. The authors describe one such malfunction, and its implications. An 8-year-old radiant heater, which appeared to be operating normally in a neonatal intensive care unit, was observed, by mere chance, to intermittently register an increased, or decreased, neonatal skin temperature of about 1 degree C, depending on personnel movements and on its location in the room. The possibility that EMI had been the cause of this malfunction was investigated. The malfunction stopped in an adjacent windowless room, but again occurred when a 146-MHz walkie-talkie (100 mW) was used within a 1-2-m radius. More complete (0.1-1,000 MHz, 4.5-10 V/m maximum) test-chamber assessment of EMI susceptibility showed that the heater malfunctioned at electric field strengths above 0.3-1 V/m over four roughly 50-MHz bands between about 10 and 600 MHz. A previous electromagnetic environment survey had documented fairly high fields (0.01-0.3 V/m, 30-1,000 MHz) in the original malfunction area. Combined results suggested that the malfunction had been due to EMI from nearby fixed-source FM transmission antennas, which could be seen from the room's windows. The device had probably been malfunctioning for months, even though it had been regularly checked during preventive maintenance. Other identical, but newer, units functioned normally, or malfunctioned negligibly. Although operation of the older device deviated only "slightly" from normal, the consequences of this malfunction could have been serious.(ABSTRACT TRUNCATED AT 250 WORDS)

Symmetry and synkinesis during rehabilitation of unilateral facial paralysis

We evaluated biofeedback rehabilitation in patients with severe chronic unilateral facial paralysis, who had intact facial-motor innervation (House grades 3 to 5). Recovery of facial function was characterized (1) by grading facial movement symmetry, and (2) by counting the number of muscles exhibiting synkinesis during maximal execution of selected facial movements (e.g., smiling). Facial function in 21 patients typically improved by one House grade. Facial symmetry recovered rapidly during the first 5 months of treatment, and then improved more slowly. However, during this latter period, examination of the relationship between symmetry and synkinesis (visualized by a graph plotting symmetry grades on the x-axis, against the number of synkinetic muscles on the y-axis) indicated that overall facial control was improving even when House grading suggested that it was not. Such information should aid facial retraining and may clarify understanding of underlying rehabilitation mechanisms.

Minimizing synkinesis during rehabilitation of the paralyzed face: preliminary assessment of a new small-movement therapy

Neuromuscular rehabilitation can reduce the severity of chronic facial paralysis, but complete recovery is frequently impeded by synkinesis. We evaluated whether or not such synkinesis could be minimized by preventing its possible reinforcement during rehabilitation. We compared "standard" therapy, which uses the appearance of synkinesis to guide rehabilitation, with a new "small-movement" therapy, which uses smaller movements that should minimize possible subthreshold reinforcement of synkinesis. Ten subjects who had had facial paralysis for 0.5 to 27 years were randomly assigned to either therapy group. Blinded assessments were performed before and after ten 1-hour treatments given over a 1-month interval. Facial movements in both groups were significantly more symmetric after treatment. Although synkinesis tended to be reduced in the small-movement group, this reduction was not significant. The new therapy was at least as good as the standard one, and it may be better. Further studies are required to demonstrate this.

Alcohol consumption and flushing response in natives of Chukotka, Siberia

OBJECTIVE

Drinking patterns and flushing response were investigated among indigenous natives of Chukotka, Siberia (162 women, 139 men). The quantification of drinking behavior could be used for comparison with other northern peoples and as a baseline for future intervention.

METHOD

Interviews, physical examinations and blood tests were performed in the Chukotka region of Siberia.

RESULTS

28% of the men and 4.5% of the women drank at least once per week. High doses per typical drinking occasion, which averaged 177.6 g of pure alcohol in men and 74.3 g in women, were reported; 10.3% of the men and 25.5% of the women reported that they experienced facial flushing after drinking. In most cases more than 20 g of alcohol was necessary to induce flushing, and two-thirds of the flushers were able to continue drinking after flushing began. No significant relationship between flushing and frequency and quantity of drinking and the prevalence of alcohol-related symptoms was found. There was a significant association between flushing by women and reports by them of their parent's flushing.

CONCLUSIONS

Flushing by Chukotka natives and its relationship to drinking behavior is different from Oriental ALDH2-deficient flushing.

The politicization of alcohol in the USSR and its impact on the study and treatment of alcoholism

Conducting research, particularly social science or health-related research, in the former Soviet Union was difficult because of the intrusion of communist ideology on public policy, theory, research, and practice. This report provides a description of drinking and alcohol-related problems in Siberia that was not previously available for publication. It reviews how the Soviet State's policies effected the study and treatment of alcoholism in Russia, and presents a critical review of these policies that would not have been permitted under the previous regime.

Urban-rural comparisons of drug-taking behavior among Alaskan youth

This study explores drug-taking behavior among Alaskan youth in urban, rural, and semiurban communities. It finds significant differences among these locations, which are largely attributable to variations in age of first trying marijuana and alcohol. Racial group effects specific to initiation into marijuana, and gender differences related to initiation to alcohol, are also found. The implications of these findings for education and prevention of drug-taking behavior are discussed, with special emphasis on racial and cultural factors.

Serum and salivary responses to oral tetravalent reassortant rotavirus vaccine in newborns

Serum and salivary responses of 95 infants to either a standard (4 x 10(4) plaque-forming units (PFU), 47 neonates) or a high dose (4 x 10(5) PFU, 48 neonates) of tetravalent reassortant rhesus rotavirus vaccine (administered at 2 days and at 6 weeks of age) were evaluated in a double-blind clinical trial. Serum and salivary IgA antibodies to the rotavirus group A common antigen were determined by ELISA and radioimmunoassay (RIA). Serum neutralizing antibodies to rhesus rotavirus were determined by fluorescent focus reduction assay. No significant differences in responses to the high versus standard dose were noted in serum or saliva. Response was influenced by cord blood antibodies. All infants who were cord blood-negative for rhesus rotavirus neutralizing antibodies (nine who received the standard dose and 20 who received the higher dose) had serum responses, compared with 42-70% of those who were cord blood-positive. The serum response rate recorded for babies with cord blood neutralizing titres > 1000 was 44%. Infants being bottle fed had a higher serum response rate than did babies being breast fed exclusively. If serum and salivary responses were combined, the response rate reached 80% for bottle fed infants. Thus, determination of serum responses alone underestimates vaccine 'take' in infants, and more so in highly endemic areas than in areas subject only to sporadic outbreaks. However, determination of salivary responses in newborn breastfed infants may be inaccurate, due to possible persistence of antibodies derived from colostrum or breast milk.

Ethanol elimination among different racial groups

This study examined the relationship between ethanol elimination and race, specifically exploring differences among Alaskan Natives, American Indians, and whites. Native Americans, believed to be of recent Asian origin, were expected to eliminate alcohol faster than whites. The data suggested that both Native American men and women eliminated alcohol faster than whites. A relationship was also found between age, gender, and rate of alcohol elimination. The implications of these findings were reviewed and specific needs for future research were noted.

Conductivity response of porous electrodes supported on perfluorosulfonic acid membranes to acidic gas mixtures

Gold or platinum films deposited on a Nafion membrane were used to measure surface conductance of the membrane. Acidic gases such as HCI or SO2, introduced as mixtures with an inert gas, were found to affect the conductance of the membrane surface facing this mixture while the other side of the membrane was constantly supplied with a moist inert gas. The relative conductance (G/Go) is most affected within the 0-0.5 and 3-4.5 vol % ranges both for HCI and SO2. The effect is higher for the Pt-deposited than it is for the gold-deposited membrane: for an HCI concentration of 1.5 vol %, G/Go is 5 for Pt deposited on Nafion while it is only 1.3 for gold deposited on Nafion. This is attributed to different geometries and porosity of the Pt and Au electrodes. No conductance response was observed for CO2 which yields with water a much weaker acid than those formed by HCI and SO2.

Haptoglobin levels among alcoholics in Alaska

The levels of haptoglobin, plasma proteins and amino acids were studied in a non-fasting population of alcoholics. In 25 subjects, only small differences were seen between the means when Native subjects were compared to non-Native. There did not appear to be any acute phase response differences between these two groups. This study did not substantiate other reports on the correlation of the severity of alcoholism with glycoprotein synthesis.

Adaptive modification of vestibularly perceived rotation

Results from Bloomberg et al. (1991) led to the hypothesis that saccades which accompany the dark-tested vestibulo-ocular reflex (VOR) tend to move the eyes towards a vestibularly derived percept of an intended oculomotor goal: also that this is so even when that percept has been adaptively modified by suitably prolonged visual-vestibular conflict. The present experiments investigate these implications by comparing the combined VOR + saccade performance with a presumed "motor readout" of the normal and adaptively modified vestibular percept. The methods employed were similar to those of an earlier study Bloomberg et al. (1988) in which it was found that after cessation of a brief passive whole body rotation in the dark, a previously seen earth-fixed target can be accurately located by saccadic eye movements based on a vestibular memory of the preceding head rotation; the so-called "Vestibular Memory-Contingent Saccade" (VMCS) paradigm. The results showed that the vestibular perceptual response, as measured after rotation by means of the VMCS paradigm, was on average indistinguishable from the combined VOR + saccade response measured during rotation. Furthermore, this was so in both the normal and adapted states. We conclude that these findings substantiate the above hypothesis. The results incidentally reaffirm the adaptive modifiability of vestibular perception, emphasing the need for active maintenance of its proper calibration according to behavioural context.

Adaptive plasticity in the gaze stabilizing synergy of slow and saccadic eye movements

When a normal human subject is briefly turned in total darkness while trying to "look" at a spatially fixed target, the vestibulo-ocular reflex (VOR) produces slow-phase compensatory eye movements tending to hold the eyes on target. However, slow-phase compensation per se is generally inadequate in these circumstances. Nevertheless it has recently been found, that even in the dark, this inadequacy tends to be corrected by supplementary saccades usually acting in the compensatory direction. The present study further investigates this phenomenon by measuring the respective contributions of saccadic, slow-phase and overall net compensation in 9 subjects tested before and after 30% adaptive attenuation of VOR slow-phase gain. In each test series, subjects attempted to stabilize their gaze on a previously seen target during each of 40 brief (approximately 0.5 s) whole body rotations (40 degrees/s, 20 degrees amp) conducted in complete darkness. The adaptive experience comprised 2 h of full-field visual suppression of the VOR during sinusoidal rotation of subject and surround at 1/6 Hz and 40 degrees/s velocity amplitude. Before adaptation, the cumulative slow-phase and cumulative saccadic components produced on average 78% and 14% respectively of the ideal (100%) compensation, thus yielding an overall net compensation which was 92% of the desired value. After adaptation, the corresponding values in the same population were 53%, 18% and 71% respectively. Thus after adaptation, the combined saccadic-slow-phase response brought the final gaze position to a point in space that was systematically shifted in the direction of head rotation (i.e. undercompensation). Subjects re-exposed to 30 min of normal visual-vestibular interaction displayed a variety of recovery patterns using different combinations of slow and saccadic eye movements. However, there was a consistent "synergistic" tendency for saccadic eye movements to improve slow-phase performance, regardless of the subject's adaptive state. In one subject, compensatory saccadic eye movements corrected a consistent directional asymmetry in the slow-phase response. It is suggested that a conscious vestibular percept of self-rotation might underlie the combined saccadic-slow-phase response, and that the net under performance after adaptation might reflect attenuation of this percept relative to the actual rotational stimulus.

Adolescent initiation into drug-taking behavior: comparisons over a 5-year interval

Acquisition curves for six substances were compared for adolescents in two samples separated by a 5-year interval. Individual variations in initiation ages were found for different substances, but the general pattern of exposures to drugs was essentially stable over the time interval. The findings suggest that there appears to be a range of first experience with drugs that extends from 13 to 16 years. Special emphasis was given to the implications which the findings have for education and intervention programs, and for further research.

AIDS cardiomyopathy: first rule out other myocardial risk factors

Consecutive autopsies of 59 male AIDS patients revealed that 21 had other myocardial risk factors: 17 were alcohol abusers and 6 had hypertension or coronary artery disease. AIDS patients with these myocardial risk factors were older (mean age 45 versus 35 years, P less than 0.01), and were more likely to have cardiomegaly (mean heart weight 397 grams versus 350 grams, P = 0.06) than patients with AIDS alone. When evaluating patients for AIDS cardiomyopathy, other myocardial risk factors must be considered.

[An unusual case: cutaneous leishmaniasis with subcutaneous nodule--successfully treated with oral ketoconazole]

We present an unusual case of cutaneous leishmaniasis with subcutaneous nodules. Treatment with ketoconazole over 5 weeks resulted in major improvement of the lesions.

Effects of methylphenidate on adolescents with aggressive conduct disorder and ADDH: a preliminary report

The effect of methylphenidate on aggression in adolescents diagnosed with both aggressive conduct disorder and attention deficit disorder with hyperactivity was assessed in nine male adolescents. After three open trials, a placebo controlled double-blind design was used. During methylphenidate treatment of the six double-blind subjects, there was a significant reduction of aggressivity (p's less than 0.05), as measured by the Adolescent Antisocial Behavior Checklist. Conners Teacher Rating Scale Hyperactivity and Aggression scores were in the predicted directions, but the differences were not statistically significant.