PubMed Health⌕ Search

Biomedical subjects

M C Moss

Publications and source records attributed to M C Moss.

11 recordsLinked to original sources
PubMed2005

Rural Vincentians' (Caribbean) beliefs about the usage of non-prescribable medicines for treating Type 2 diabetes.

AIMS: To explore beliefs among persons in St. Vincent, a rural Caribbean Community, regarding the usage of non-prescribable medicines for treating Type 2 diabetes. METHODS: A phenomenological enquiry explored people's experiences and the manner in which they interpret these. One focus-group interview was conducted of persons attending a rural diabetes clinic in St Vincent to generate insights into the phenomenon. Analysis was undertaken using the four steps utilized in phenomenological studies of bracketing, intuiting, analysis and description. The findings result in deeper understanding and definition of the phenomenon. RESULTS: A variety of non-prescribable, predominantly herbal and folk, medicines were commonly used as a means of self care in diabetes. Usage was underpinned by a system of lay beliefs about diabetes and beliefs in the treatment efficacy of folk medicine. A strong religious influence formed the basis of diabetes treatment and offered some symptom relief and therefore treatment satisfaction through spiritual revelations about remedies. Conventional medicines were taken in conjunction with non-prescribable treatments or else not at all. CONCLUSIONS: Non-prescribable medicines were believed by participants to be efficacious. Conventional medication was perceived as an access to medical care. Study findings may be relevant to other rural populations with strong social and religious mores.

Adult↗
PubMed1999

Cognitive properties of sedation agents: comparison of the effects of nitrous oxide and midazolam on memory and mood.

OBJECTIVES: To compare the effects of nitrous oxide and midazolam on cognition and mood. DESIGN: A three-way, counterbalanced, cross-over study, using patients receiving conscious sedation for routine dental treatment. METHODS: On each of three separate visits, patients performed a computerised test battery to determine baseline cognitive performance. Then, following administration of either midazolam, nitrous oxide, or no drug, patients re-performed the test battery. Finally, patients completed visual analogue scales assessing their subjective mood state. RESULTS: Relative to baseline performance, midazolam administration produced significantly slower reaction times compared with nitrous oxide and no-drug conditions. Furthermore, patients receiving midazolam were impaired in accuracy relative to the other conditions on many of the cognitive tasks, particularly those assessing the recall of information. Patient performance in nitrous oxide and control conditions did not significantly differ. These results could not be explained by differences in mood between the conditions, as subjective mood ratings during midazolam or nitrous oxide administration were very similar. CONCLUSIONS: It is important for clinicians to be aware that peri-operative recall of information is reduced in patients who have undergone midazolam sedation. This is an advantage for patients who are anxious, and do not wish to be aware of the operative treatment being performed. However, as the cognitive impairment is enduring, an adult escort and written post-operative instructions should be mandatory for midazolam sedation patients. In contrast, the use of nitrous oxide sedation does not significantly impair higher cognitive tasks and thus patients receiving nitrous oxide sedation can resume normal activities in the post-operative period.

Adolescent↗
PubMed1999

Cognitive performance, hyperoxia, and heart rate following oxygen administration in healthy young adults.

It was recently established that supplemental oxygen administration significantly enhances memory formation in healthy young adults. In the present study, a double-blind, placebo-controled design was employed to assess the cognitive and physiological effects of subjects' inspiration of oxygen or air (control) prior to undergoing simple memory and reaction-time tasks. Arterial blood oxygen saturation and heart rate were monitored during each of six phases of the experiment, corresponding to baseline, gas inhalation, word presentation, reaction time, distractor and word recall, respectively. The results confirm that oxygen administration significantly enhances cognitive performance above that seen in the air inhalation condition. Subjects who received oxygen recalled more words and had faster reaction times. Moreover, compared to participants who inhaled air, they exhibited significant hyperoxia during gas administration, word presentation, and the reaction-time task, but not at other phases of the experiment. Compared to baseline, heart rate was significantly elevated during the word presentation, reaction-time, and distractor tasks in both the air and oxygen groups. In the oxygen group, significant correlations were found between changes in oxygen saturation and cognitive performance. In the air group, greater changes in heart rate were associated with more improved cognitive performance. These results are discussed in the context of cognitive demand and metabolic supply. It is suggested that under periods of cognitive demand a number of physiological responses are brought into play that serve to increase the delivery of metabolic substrates to active neural tissue. These mechanisms can be supplemented by increased availability of circulating blood oxygen, resulting in an augmentation of cognitive performance. Heart rate reactivity and the capacity for increased blood oxygen appear to be important physiological individual differences mediating these phenomena.

Adult↗
PubMed1998

Oxygen administration selectively enhances cognitive performance in healthy young adults: a placebo-controlled double-blind crossover study.

It was recently demonstrated that oxygen administration can improve performance on a simple word recall task in healthy young adults. This study was aimed at determining the impact of various durations of oxygen administration on a wider range of cognitive measures. This was achieved using the Cognitive Drug Research computerised test battery, and employing a double-blind, placebo-controlled crossover design. Over a period of 7 weeks, 20 participants were trained and subsequently assessed on the test battery under several durations of oxygen inhalation; air administered in an identical fashion served as a control. The results provided support for our earlier work in that increases were found in both immediate and delayed word recall. In addition, oxygen administration significantly improved performance on several measures of attention and vigilance. Simple reaction time, choice reaction time, digit vigilance reaction time and picture recognition reaction time were improved in a manner which depended on the duration of oxygen inspired. With the exception of word recall, no significant improvements were found for any measure of accuracy, nor were word recognition, digit memory scanning, or spatial memory improved. These results are discussed in the context of stages of information processing and are consistent with the hypothesis that cognitive performance is "fuel-limited" and can be differentially augmented by increasing the availability of the brain's metabolic resources.

Adult↗
PubMed1998

Oxygen and cognitive performance: the temporal relationship between hyperoxia and enhanced memory.

Oxygen administration coinciding with word presentation enhances word recall in humans, suggesting that elevated levels of circulating blood oxygen may be available to neural memory consolidation processes. This double-blind experiment examined the relationship between blood oxygen levels and cognitive performance when oxygen was inspired for 2 min at different times relative to a simple word recall task, forward digit span and backward digit span. Transient hyperoxia, measured by haemoglobin-bound oxygen, was evident following oxygen inspiration. Neither forward nor backward digit span was affected by oxygen administration. Word recall (12 min following word presentation) was enhanced when oxygen was administered 5 min prior to, immediately before or immediately following word presentation; but not 10 min prior to, 5 min following nor 10 min following, word presentation. These data suggest that oxygen administration can selectively enhance aspects of cognitive performance and support a hypothesis whereby supplemental blood oxygen is sequestered by neural mechanisms involved in memory consolidation.

Adult↗
PubMed1996

Oxygen administration enhances memory formation in healthy young adults.

Despite numerous studies indicating that transient cerebral oxygen depletion has a detrimental effect on cognition, surprisingly little research has examined the possibility of cognitive enhancement following elevated oxygen levels in healthy adults. Here, we present evidence demonstrating that oxygen administration improves memory formation. Inhalation of oxygen immediately prior to learning a word list resulted in a significant increase in mean number of words recalled 10 min later, compared to subjects who inhaled oxygen immediately prior to recall or to controls who underwent no intervention. In a second experiment, the learning-test interval was increased to 24 h and, again, only pre-learning (but not pre-test) oxygen administration resulted in significant memory facilitation. In experiment 3, inhalation of oxygen prior to learning was compared to inhalation of compressed air, oxygen (but not compressed air) resulted in a significant increase in word recall 24 h later. In no experiment did oxygen have a significant effect on any mood item measured. We interpret these data as indicating that increased availability of cerebral oxygen facilitates cognition, including memory consolidation. The implications for the psychopharmacology of cognitive enhancement are considered in the context of cholinergic systems and neural metabolism.

Adult↗
PubMed1996

Volume changes within the true pelvis during disruption of the pelvic ring--where does the haemorrhage go?

Fractures of the pelvis are not only common but are very varied in their complexity. They represent 3% of all fractures (1), they account for 1 in every 1000 surgical admissions and are the third most commonly encountered injury in motor vehicle accident fatalities (2). However, only a small percentage of all pelvic fractures are associated with major disruption of the pelvic ring (3). Life threatening haemorrhage is a frequent complication of major pelvic fractures (1, 4) and haemorrhage is the leading cause of death in these patients (5, 6). It was believed that fracture and subsequent displacement of the ring greatly increased pelvic volume. However, clinical practice seemed to indicate that this might not be true. This study aimed to assess the change in pelvic volume which occurs in severely displaced pelvic fractures. A model of the bony pelvis was designed to permit extreme displacements of the symphyseal and sacroiliac joints. The volume of a polythene balloon placed within the true pelvis was measured as an indication of true pelvic volume. Our finding was that the increase in the volume of the true pelvis which occurs in a fracture with massive diastasis is much smaller than previously assumed.

Fractures, Bone↗
PubMed1985

A morphometric study of the endocrine and exocrine capillaries of the pancreas.

In passing from islets to the exocrine part of the gland, pancreatic capillaries change their character. Islet capillaries are significantly wider than exocrine (5.27 micrometers, diameter compared with 4.35 micrometers), thinner walled and have many more fenestrations micrometers-1 of endothelium (1.3 compared with 0.13). The point of transition at the edge of the islet is very abrupt, for capillaries that are in contact with both endocrine and exocrine tissue ('edge capillaries') have significantly more fenestrae on the side facing the endocrine cells than the side facing exocrine (1.46 fenestrae micrometers-1 compared with 0.3 micrometers-1). The structure of these edge capillaries suggests that the factors operating to induce the formation of fenestrae do so over extremely short distances. The relationship between fenestrations, the high blood flow and high water flux seen in endocrine glands is discussed.

Animals↗