PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “DEXTERITY”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 955 records · Page 53Linked to original sources

Delta-aminolevulinic acid dehydratase (ALAD) polymorphism and susceptibility of workers exposed to inorganic lead and its effects on neurobehavioral functions.

We carried out a cross-sectional study on a group of male workers to determine the frequency of delta-aminolevulinic acid dehydratase (ALAD) polymorphisms among Chinese, Malays and Indians workers who were exposed to low to medium levels of inorganic lead. Also, the association between ALAD1 and ALAD2 genotypes and neurobehavioral functions among these workers were investigated. A total of 120 male workers were studied. Blood and urine were collected for each worker to determine the ALAD genotypes, blood lead levels, ALAD, and urinary delta-aminolevulinic acid (ALAU). ALAD1-1 was the predominant genotype for all three ethnic groups while ALAD2-2 was the rarest. The distribution of ALAD1-2 was higher among Malays (16.7%) and Indians (14.3%), compared to Chinese (3.6%). Selected tests from the World Health Organization Neurobehavioral Core Test Battery (WHO-NCTB) were used. Although workers in the ALAD1-1 and ALAD1-2/2-2 groups had comparable blood lead levels, the 106 workers with ALAD1-1 genotypes have significantly higher urinary ALA and significantly poorer neurobehavioral scores involving motor dexterity compared with those who have ALAD1-2/2-2 genotypes (13 workers). It is postulated that the ALAD2 allele may exert protective measures against the neurotoxic effects of lead. Further study involving a larger cohort of workers with the ALAD2 allele would be needed to confirm this hypothesis.

Adult↗

Possibilities of newer ALAD polymorphism influencing human susceptibility to effects of inorganic lead on the neurobehavioral functions.

OBJECTIVE: A cross-sectional study was conducted to study the association between some new ALAD polymorphism and susceptibility to effects of inorganic lead on the neurobehavioral functions. METHOD: We recruited 120 healthy male workers with lead exposure in a factory which manufacture lead stabilizer. The ALAD SNPs studied were HpyCH4, HpyIV RFLP in intron 6, Rsa and Msp RFLP in exon 4, Sau3A in intron 12 and Rsa39488 in exon 5. The World Health Organization Neurobehavioral Core Test Battery (WHO-NCTB) and a few other tests were used. General linear model (GLM) was applied to compare outcome scores between subgroups of each ALAD SNP while controlling for possible confounders. RESULTS: The mean age of the workers was 39.7 years (S.D. 10.7), mean exposure duration of 10.2 years (S.D. 7.9) and mean blood lead of 22.1 microg/dl (S.D. 9.4). Among the 6 SNPs studied, Rsa and Rsa39488 appear to be the main candidate SNPs. Workers with Rsa and Rsa39488 ALAD 2-2 genotypes fare significantly better in the Aiming Pursue Test Correct (AC), Groove Peg Board non-preferred hand (GPNP), Groove Peg Board Mean (GPM), San Ana Preferred Hand (SAP), San Ana Both Hands (SAB) and AC, GPNH, GPM, Digit Symbol (DIS) tests; respectively compared to Rsa and Rsa39488 ALAD 1-1/1-2 genotypes adjusted for age, race, exposure duration and blood lead levels. CONCLUSION: The presence of the homozygote Rsa and Rsa39488 ALAD 2-2 seems to offer some protection against the effect of lead on motor dexterity function. While it may appear that newer ALAD polymorphism other than the commonly reported Msp SNP might influence human susceptibility to effects of inorganic lead on the neurobehavioral functions further study involving a larger cohort of workers with Rsa and Rsa39488 ALAD2 allele would be needed to confirm this inference.

Adult↗

Effects of sarin and cyclosarin exposure during the 1991 Gulf War on neurobehavioral functioning in US army veterans.

BACKGROUND: During the Gulf War (GW), in early March 1991, a munitions dump at Khamisiyah, Iraq, was destroyed. Later, in 1996, the dump was found to have contained the organophosphate chemical warfare agents, sarin and cyclosarin. METHODS: Data collected in a study conducted between 1994 and 1996, before the Khamisiyah incident was publicly disclosed, were used to examine neurobehavioral task performances of GW veterans (n=140) categorized as having received high, moderate, or low-to-no exposure dose levels to sarin and cyclosarin at Khamisiyah, Iraq. Exposure levels were based on modeled estimates of the exposure plume and on troop location information at the time of the Khamisiyah event. Based on recent findings observed in follow-up studies of persons exposed to sarin during the 1995 terrorist attacks in Japan, we hypothesized that exposure to sarin and cyclosarin would be associated with poorer performances on objective neurobehavioral tasks in specific functional domains (particularly in visuospatial abilities and psychomotor functioning) in a dose-dependent manner. RESULTS: Sarin and cyclosarin exposure was significantly associated with less proficient neurobehavioral functioning on tasks involving fine psychomotor dexterity and visuospatial abilities 4-5 years after exposure. CONCLUSIONS: Findings suggest a dose-response association between low-level exposure to sarin and cyclosarin and specific functional central nervous system effects 4-5 years after exposure.

Adult↗

The human parietal cortex is involved in spatial processing of tongue movement-an fMRI study.

The human tongue is so sensitive and dexterous that spatial representations of the inside of the oral cavity for the tongue movement are naturally expected to exist. In the present study, we examined the brain activity associated with spatial processing during tongue movements using a functional magnetic resonance imaging technique. Twenty-four normal subjects participated in the study, which consisted of a periodic series of three blocks; resting of the tongue, tongue movement (pressing the inside of a tooth with the tip of the tongue), and tongue retraction. The cerebral fields of activation during the tongue movement to the left and right side relative to those during rest were found in the primary sensorimotor area and supplementary motor area bilaterally, and in the left inferior parietal lobule (IPL). The activation areas during the tongue retraction relative to those during rest were almost the same, except that activation in the left IPL was not observed. The fields of activation during tongue movement to the left and right side relative to those during tongue retraction were found bilaterally in the dorsal premotor area, superior parietal lobule (SPL), and the IPL. The results indicate that the bilateral SPL and IPL were specifically involved in the processing for human tongue movement. Although no significant laterality was observed, the left parietal area tended to show greater activation in statistical values and area than the right parietal area, thus indicating the possibility that this processing for human tongue movement is related to that for language.

Adult↗

Selective activation and deactivation of the human brain structures between speeded and precisely timed tapping responses to identical visual stimulus: an fMRI study.

We investigated the difference between brain activities in speeded and precisely timed responses to identical visual stimulus using fMRI. Stimulus used was a row of seven light-emitting diodes (LEDs) lightened up one after another with constant speed within a trial but with various speeds between trials. Subjects were asked to execute finger-thumb tapping with the right hand in response to the onset of the first LED light in the reaction time (RT) task and in anticipation of the onset of the last (i.e., seventh) LED light in the timing task. In control condition, they were asked to passively view the stimulus without motor response. Results showed that various movement-related areas including contralateral cingulate motor cortex were commonly activated for both tasks relative to the control condition, suggesting these structures are involved in general perception and response execution rather than specific function for speeded or precisely timed responses. In the RT task, the presupplementary motor area extending to the cingulate sulcus was activated more strongly than in the timing task probably to focus attention to the onset of the first LED light unpredictably presented after random foreperiods. The lateral occipital area extending to the temporo-parieto-occipital junction was activated more strongly in the timing task than in the RT task; the same area was deactivated in the RT task relative to the control condition. Auditory-related areas were also deactivated in the both tasks. This inter- and intramodal task-specific modification including deactivation underscores significance of the context for perception and action and can have an important role in dexterous or skilled performance.

Adult↗

Prospective demonstration of short-term motor plasticity following acquired central pareses.

The effect of newly acquired central pareses on functional MRI (fMRI) signal pattern is not known, since up to now all investigated patients were examined while they already experienced the motor weakness. We describe the first prospective and controlled study demonstrating the impact of new, acquired central pareses on fMRI motor activation pattern. Six patients suffering from a new central paresis after resection of a brain tumor infiltrating the central region were prospectively compared with a control group of five patients without postoperative paresis and a group of six healthy, age-matched controls who were investigated at two time points. fMRI signal was postoperatively analyzed during the performance of hand motor tasks and compared to the preoperative fMRI results. The relative signal change between rest and activation was evaluated for five cortical regions: the primary motor cortex (M1) and the ipsilateral primary motor cortex (M1i), the supplementary motor area (SMA), the premotor area (PMA), and the superior parietal lobule (SPL). In the patients with new postoperative central pareses, significant (P = 0.0313) decreases in fMRI activation were found in M1, whereas significant (P = 0.0313) increases were found in SMA and PMA. For M1i and SPL, there was a signal increase on average as well, but it failed to reach significance (P = 0.1250). In both control groups, no significant changes between both examinations were seen. Even though the number of investigated patients is too small to draw definite conclusions, our results support the concept of short-term motor plasticity being mediated by redundant systems that may take over function after damage of the primary motor cortex. The findings potentially also reflect increased functional demands imposed upon the motor network subsequent to a loss of dexterity.

Adult↗

Modular organization of finger movements by the human central nervous system.

The motor system may generate automated movements, such as walking, by combining modular spinal motor synergies. However, it remains unknown whether a modular neuronal architecture is sufficient to generate the unique flexibility of human finger movements, which rely on cortical structures. Here we show that finger movements evoked by transcranial magnetic stimulation (TMS) of the primary motor cortex reproduced distinctive features of the spatial representation of voluntary movements as identified in previous neuroimaging studies, consistent with naturalistic activation of neuronal elements. Principal component analysis revealed that the dimensionality of TMS-evoked movements was low. Principal components extracted from TMS-induced finger movements resembled those derived from end-postures of voluntary movements performed to grasp imagined objects, and a small subset of them was sufficient to reconstruct these movements with remarkable fidelity. The motor system may coordinate even the most dexterous movements by using a modular architecture involving cortical components.

Adult↗

Ophthalmology resident surgical competency: a national survey.

PURPOSE: To describe the prevalence, management, and career outcomes of ophthalmology residents who struggle with surgical competency and to explore related educational issues. DESIGN: Fourteen-question written survey. PARTICIPANTS: Fifty-eight program directors at Accreditation Council on Graduate Medical Education-accredited, United States ophthalmology residency programs, representing a total of 2179 resident graduates, between 1991 and 2000. METHODS: Study participants completed a mailed, anonymous survey whose format combined multiple choice and free comment questions. MAIN OUTCOME MEASURES: Number of surgically challenged residents, types of problems identified, types of remediation, final departmental decision at the end of residency, known career outcomes, and residency program use of microsurgical skills laboratories and applicant screening tests. RESULTS: One hundred ninety-nine residents (9% overall; 10% mean per program) were labeled as having trouble mastering surgical skills. All of the programs except 2 had encountered such residents. The most frequently cited problems were poor hand-eye coordination (24%) and poor intraoperative judgment (22%). Most programs were supportive and used educational rather than punitive measures, the most common being extra practice-laboratory time (32%), scheduling cases with the best teaching surgeon (23%), and counseling (21%). Nearly one third (31%) of residents were believed to have overcome their difficulties before graduation. Other residents were encouraged to pursue medical ophthalmology (22%) or to obtain further surgical training through a fellowship (21%) or a supervised practice setting (12%); these residents were granted a departmental statement of satisfactory completion of residency for Board eligibility. Twelve percent were asked to leave residency. Of reported career outcomes, 92% of residents were practicing ophthalmology, 65% as surgical and 27% as medical ophthalmologists. Ninety-eight percent of residency programs had microsurgical practice facilities, 64% had a formal teaching course, and 36% had mandatory practice time. Most programs (76%) did not perform applicant vision or dexterity screening tests; questions existed about the legality and validity of such tests. CONCLUSIONS: The issue of ophthalmology residents who struggle to develop surgical competency appears common. Although many problems appear to be remediable with time, practice, and dedicated, patient teachers, more specific guidelines for a statement of surgical competency are likely necessary to standardize the Board certification process.

Career Choice↗

Clinical relevance of rehabilitation programs for patients with idiopathic Parkinson syndrome. II: Symptom-specific therapeutic approaches.

Clinical symptoms of the idiopathic Parkinson's syndrome (IPS) are numerous. Clinical experience as well as pharmacological research identified symptoms not responsive to dopaminergic stimulation. These symptoms in particular were the target of rehabilitative therapy approaches. Several of these approaches have been evaluated in prospective studies. In the present paper, these studies and the respective therapeutic interventions were categorized and rated concerning their clinical relevance and their study design supporting a differential therapeutic approach. Symptoms were arranged relating to their clinical relevance and specific therapeutic approaches were described and rated. The rating was based on a novel developed approach to check for clinical relevance. In addition, areas in need of further and more intensive scientific research, as depression, cognitive deficits, and tremor, were identified. On the contrary, conclusive therapeutic approaches were available for the treatment of symptoms like gait and postural disturbances and dysarthria. Some advice for the therapy of muscular weakness, dexterity problems and dysphagia was given, but further studies are warranted in these fields.

Clinical Trials as Topic↗

Focal peripheral neuropathies in instrumental musicians.

Instrumental musicians often seek medical consultation for symptoms suggestive of nerve entrapment. About 20% of those seen in the author's performing artists' clinic were diagnosed with a focal neuropathy. In general, neuropathies that are most common in the overall population tend also to be most common among musicians, although some expectations exist, including, for example, localized peri-oral sensory syndromes associated with playing a brass instrument, and, possibly, ulnar neuropathies related to the playing position of bowed string players. The diagnosis is made, as always, by careful clinical assessment, including observation of the instrumentalist playing, with ancillary procedures such as nerve conduction studies and needle electromyography adding to the accuracy of the diagnosis. Treatment is similar to that used in nonmusicians, but certain factors, including the musician's requirement for extraordinary neuromuscular dexterity, may influence the therapeutic decisions. Very limited long-term outcome results are available, and additional studies in musicians would be helpful in determining the most appropriate therapeutic approaches. Virtually no longitudinal studies have been performed to look at methods for preventing these disorders.

Adolescent↗

Prosthetic rehabilitation for a patient with microstomia: a clinical report.

This clinical report describes the fabrication of a collapsible maxillary removable complete overdenture using a sectional impression tray technique and a custom-made palatal hinge mechanism for a partially edentulous woman with microstomia resulting from scleroderma. As microstomia is frequently associated with poor manual dexterity, an instrument was fabricated to assist the patient in removing the prosthesis.

Adult↗

The cutaneous contribution to adaptive precision grip.

Only after injury, or perhaps prolonged exposure to cold that is sufficient to numb the fingers, do we suddenly appreciate the complex neural mechanisms that underlie our effortless dexterity in manipulating objects. The nervous system is capable of adapting grip forces to a wide range of object shapes, weights and frictional properties, to provide optimal and secure handling in a variety of potentially perturbing environments. The dynamic interplay between sensory information and motor commands provides the basis for this flexibility, and recent studies supply somewhat unexpected evidence of the essential role played by cutaneous feedback in maintaining and acquiring predictive grip force control. These examples also offer new insights into the adaptive control of other voluntary movements.

Adaptation, Physiological↗

Robotic pyeloplasty: technique and results.

The da Vinci robotic system can be used to perform dismembered and nondismembered pyeloplasty techniques effectively. Robotics not only seems to improve dexterity and surgical precision but also provides an ergonomic surgical environment for a surgeon performing complex reconstructive procedures such as pyeloplasty. Although performance-enhancing features of the da Vinci robot seem to decrease the difficulty of intracorporeal suturing, a learning curve also exists for telerobotic procedures. This learning curve may decrease as experience with telerobotics increases and as advances in technology are introduced. Presently, the interaction between the primary and assistant surgeon seems crucial to the success of the procedure. Although the early clinical experience with robotic pyeloplasty is favorable, continuing clinical evaluation and careful follow-up are required to determine if the procedure is as efficacious in the long run as open pyeloplasty and laparoscopic pyeloplasty.

Follow-Up Studies↗

Prominent venous valves in hypoplastic right hearts.

To investigate the hypothesis that embryologic abnormalities in the venous valves may be associated with abnormal cardiac development, we examined the right atrial morphologic characteristics in 20 hearts with underdevelopment of the right heart and 17 normal hearts. In the study group, 16 (80%) of the patients had significantly enlarged eustachian valves, one (5%) was slightly enlarged, and three (15%) were smaller than expected. Five (25%) had cor triatriatum dexter. In comparison, eustachian valves in the control specimens were prominent in only one (6%), normal in five (29%), and almost absent in eight (47%). The thebesian valve was also more prominent in the study cohort when compared with controls (p < 0.05). No other morphologic features of the right atrium analyzed in this study differed from those found in normal specimens. We speculate that failure of the venous valves to regress appropriately may create abnormalities in fetal circulation that predispose the fetus to maldevelopment of the right heart structures.

Adult↗

Homocysteine levels and decline in physical function: MacArthur Studies of Successful Aging.

PURPOSE: To test whether elevated homocysteine levels are associated with an increased risk of decline in physical function in older persons. METHODS: We performed a prospective cohort study of 499 highly functioning men and women aged 70 to 79 years who were enrolled in the MacArthur Studies of Successful Aging. We measured total homocysteine levels and performance-based physical function at baseline; physical function measures were repeated an average of 28 months later. A summary measure of physical performance from tests of balance, gait, lower body strength and coordination, and manual dexterity was developed, and a change score was calculated as the difference in scores from 1988 to 1991. RESULTS: The mean (+/-SD) homocysteine level was 11.6 +/- 4.3 micromol/L. With each SD increase in homocysteine, there was an increased risk of being in the worst quartile of decline in physical function (odds ratio = 1.5; 95% confidence interval: 1.2 to 1.9) in analyses that adjusted for age, sex, baseline physical performance, smoking status, vitamin B(12) levels, and incident stroke. Similar results were seen when change in physical performance was treated as a continuous variable. CONCLUSION: Older persons with elevated plasma homocysteine levels are at an increased risk of decline in physical function.

Aged↗

Surgeon-specific factors in the acquisition of laparoscopic surgical skills.

BACKGROUND: Training and experience vary widely among surgeons performing laparoscopic surgery (LS). Visual perceptual demands are greater for LS than for traditional surgery, necessitating greater understanding of surgeon variables in skill acquisition and performance. METHODS: During an LS skills course incorporating didactic and simulator-based instruction, 94 surgeons completed an experience/demographic questionnaire, a test of course-specific knowledge acquisition, 10 trials of three dexterity drills, 15 suturing trials using course-specific methods, and 3 standardized tests of visual perception. RESULTS: Age, years posttraining, and visual perception correlated significantly with time required to complete drills and suturing trials (Pearson correlations ranged from r = 0.21, P <0.05, to r = 0.51, P <0.001) even after statistically controlling for variations in knowledge acquisition, which correlated (r = 0.30, P <0.01) with suturing speed. CONCLUSIONS: Surgeon variables play a significant role in speed of acquisition and performance of LS skills. Further studies need to elucidate their role in quality of LS performance.

Adult↗

What do master surgeons think of surgical competence and revalidation?

BACKGROUND: There has been on-going debate and public interest in surgical competence in recent years. METHODS: A Delphi reiterative opinion survey was conducted among master surgeons on selection of surgical trainees, methods of assessment of progress of surgical trainees, and revalidation of established consultant surgeons. RESULTS: Selection-the current methods of trainee selection were considered inadequate and in need of revision. The important attributes recognized by group are cognitive factors, innate dexterity, and personality. Important aspects of personality include decision-making ability, insight, team spirit, and emotional stability. Assessment during training-the majority view was that this should be based on clinical judgement/skills, operative skills, and cognitive ability. Assessment of technical ability should be based on standardized checklists. Research within training programs was encouraged but academic achievement does not reflect surgical competence. There was a majority verdict for an exit clinical examination. Revalidation-the group agreed on the need for competence checks during the professional career of surgeons. These should cover knowledge, clinical, operative, and humanistic skills; but expressed concern on the feasibility of a revalidation system that can reliably assess the range of skills needed for surgical competence. There was a majority vote against an internal appraisal system. External assessment by nationally appointed 'assessors' was considered preferable. CONCLUSIONS: Both selection and assessment of surgical trainees require changes and standardization. Although revalidation is necessary, concern was expressed on the reliability and validity of existing and proposed systems.

Clinical Competence↗

Double gloving and practice attitudes among surgeons.

BACKGROUND: Exposure to blood and body fluids while operating places surgeons at risk. Double gloving is a safety measure, which decreases this risk. However, many surgeons do not incorporate this precaution into their personal practice. This study evaluates surgeons' gloving practices and hepatitis status. METHODS: A questionnaire was sent to all consultant surgeons and residents in the surgical specialties in the Capital Health region, University of Alberta. A double mail-out design was used. A second questionnaire, containing information on safety issues, was sent to the general surgeons (consultants and residents) who did not double glove to ascertain whether this information would change their practice. RESULTS: In all, 268 surgeons and residents were sent the original questionnaire; 170 replied (63.4% response rate.) Fifty-seven percent of the respondents do not double glove (none of the urologists double glove versus 87% of orthopedic surgeons). The most common reason sited was a decrease in manual dexterity (46%). Ninety-seven percent of respondents are immunized for hepatitis B with 53% having had their titres recently checked. Thirty-seven general surgeons received the evidence on safety issues but only 9 (23%) of them would change their practice as a result of this information. CONCLUSIONS: The majority of surgeons and residents do not double glove. Even when provided with good evidence of efficacy, few surgeons contemplate adopting safety techniques.

Attitude of Health Personnel↗