Antarctic Cenozoic climate history from sedimentary records: ANDRILL and beyond.

Mounting evidence from models and geological data implies that the Antarctic Ice Sheet may behave in an unstable manner and retreat rapidly in response to a warming climate, which is a key factor motivating efforts to improve estimates of Antarctic ice volume contributions to future sea-level rise. Here, we review Antarctic cooling history since peak temperatures of the Middle Eocene Climatic Optimum (approx. 50 Ma) to provide a framework for future initiatives to recover sediment cores from subglacial lakes and sedimentary basins in Antarctica's continental interior. While the existing inventory of cores has yielded important insights into the biotic and climatic evolution of Antarctica, strata have numerous and often lengthy time breaks, providing a framework of 'snapshots' through time. Further cores, and more work on existing cores, are needed to reconcile Antarctic records with the more continuous 'far-field' records documenting the evolution of global ice volume and deep-sea temperature. To achieve this, we argue for an integrated portfolio of drilling and coring missions that encompasses existing methodologies using ship- and sea-ice-/ice-shelf-based drilling platforms as well as recently developed seafloor-based drilling and subglacial access systems. We conclude by reviewing key technological issues that will need to be overcome.

Triassic amphibian from Antarctica.

A fossil bone fragment-the first record of tetrapod life from Antarctica-was found near Graphite Peak in the upper Beardmore Glacier area (85 degrees 3.3'S; 172 degrees 19'E). The fragment was embedded in a pebbly quartzose sandstone, probably of fluvial origin, in the lower part of the Triassic Fremouw Formation (as yet undefined), which contains Dicroidium in the upper part. The fossil horizon is only 76 meters, stratigraphically, above the Glossopteris-bearing Buckley Formation, a coal-bearing sequence of Permian age. The bone fragment is the back portion of a left mandibular ramus of a labyrinthodont amphibian. This identification is based on the characteristic labyrinthodont external surface sculpturing, with indications of "mucous grooves," as well as on other osteological features.

The cardiovascular capacities of adults with Down syndrome: a comparative study.

The purpose of this study was to compare the cardiovascular capacities of individuals with Down syndrome (DS) to individuals without Down syndrome who are mentally retarded. Sixteen young adults with DS and 16 individuals without DS (12 males and 4 females, respectively), all with mild/moderate mental retardation, participated in this study. Peak VO2 (absolute and relative), VE (1.min-1), heart rate (HR, b.min-1), and RER (VCO2/VO2) were determined by exercise tests utilizing a treadmill (TM) and Schwinn Air-Dyne ergometer (SAE). The best test result was chosen from the TM and SAE tests and used for statistical comparisons. Cardiac output (Q, 1.min-1) was measured while standing quietly and while walking at 3 mph, 0% grade, using the CO2 rebreathing method for 11 (9 males and 2 females) subjects from each group. Arteriovenous oxygen differences (a-v O2), cardiac index (QI), and stroke volume (SV) were calculated from VO2, Q, HR, and body surface area. Peripheral vascular resistance (PVR), left ventricular work index (LVWI), and left ventricular stroke work index (LVSWI) were calculated from mean arterial pressure, Q, QI, and stroke volume index. Results showed that individuals without DS had statistically significant (P less than 0.01) higher mean peak VO2 (35.6 vs 24.6 ml.kg-1.min-1; 2567 vs 1683 ml.min-1), VE (89.3 vs 59.2 1/min-1), and HR (179 vs 159 b.min-1) than individuals with DS, respectively. No differences in RER were seen between the groups. No differences were seen in cardiovascular parameters measured while quietly standing.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of lower body positive pressure on the exercise capacity of individuals with spinal cord injury.

The purpose of this study was to determine the effect lower body positive pressure (LBPP) has on the cardiovascular/exercise capacities of individuals with spinal cord injury (SCI) during both arm crank exercise (ACE) and wheelchair exercise performed on a treadmill (WCTM). Ten male adults (age = 31.1 +/- 10 yr) with SCI and five male nondisabled (ND) adults (31.2 +/- 10 yr) participated in this study. The ND subjects performed ACE only. For subjects with SCI, significantly higher (P < 0.025) peak VO2 (1042 +/- 212 vs 839 +/- 218 ml.min-1), peak VE (46 +/- 17 vs 35 +/- 9 l.min-1), and work rate (50 +/- 15 vs 40 +/- 13 W) were seen during ACE with LBPP. No significant differences for peak VO2, VE, or work rate were seen for the ND subjects with LBPP during ACE. In addition, significantly higher peak VO2 (960 +/- 322 vs 828 +/- 312 ml.min-1) was recorded with LBPP for the subjects with SCI during WCTM. Cardiac output (Q, l.min-1; CO2 rebreathing method) was measured at 50% peak VO2 for both ND subjects and subjects with SCI during ACE. Subjects with SCI demonstrated significantly higher SV (94 +/- 20 vs 84 +/- 20 ml) with LBPP. No differences were observed in SV at 50% peak VO2 during ACE for the ND subjects with LBPP. The results of this study suggest that for individuals with SCI, LBPP augments exercise capacity by preventing the redistribution of blood to the lower extremities.

Comparison of adverse events associated with use of mefloquine and combination of chloroquine and proguanil as antimalarial prophylaxis: postal and telephone survey of travellers.

OBJECTIVE: To compare the frequency of adverse events, particularly neuropsychiatric effects, from mefloquine and from chloroquine plus proguanil as used for malaria chemoprophylaxis. DESIGN: Retrospective questionnaire to travellers taking either regimen between November 1993 and February 1995; telephone interview with those reporting pronounced side effects. SETTING: Travellers from Britain who consulted an advisory helpline. SUBJECTS: 1214 adults taking mefloquine and 1181 taking chloroquine plus proguanil. MAIN OUTCOME MEASURES: Reported presence of and degree of disability from 12 neuropsychiatric and other symptoms, as assessed by the subjects and by referees and on the basis of behaviour change. RESULTS: There were equal rates of any side effects (40%) and of stopping or changing medication. Overall, neuropsychiatric adverse events were significantly more common in travellers taking mefloquine. In all, 333 neuropsychiatric adverse events were reported by 1214 travellers taking mefloquine, compared with 189 such events in 1181 travellers taking proguanil plus chloroquine (P < 0.001). In all, 0.7% of travellers taking mefloquine had disabling neuropsychiatric adverse effects, compared with 0.09% of those taking proguanil plus chloroquine (P = 0.021). Two travellers taking mefloquine (1 in 607) were admitted to hospital as a result of the adverse event, compared with 1 in 1181 travellers taking proguanil plus chloroquine. CONCLUSION: There is a significant excess of adverse neuropsychiatric events of intermediate degrees of severity associated with the use of mefloquine compared with proguanil plus chloroquine. This finding may also explain the discrepant findings between earlier studies and clinical experience.

Heparin versus saline flushing solutions in a small community hospital.

Since no nursing policy on flushing procedures existed in their small community hospital, the authors thought it would be useful to clarify recent reports of the equivalency of saline to heparin flushes in their patient group before establishment of such a policy. They conducted a 2 month double-blinded, cross-over study of catheter failures when using either saline or heparin 10 units/mL flushing solutions. All medical and surgical floor patients were included in the study. Floor nurses were used as observers and characterized catheter failures as either loss of patency or phlebitis. Heparin was shown to cause more phlebitis than saline (p less than .025), but no difference was found between the two flushing solutions in loss of patency. Data revealed a statistically significant advantage to using saline flushes when both loss of patency and phlebitis were combined (p less than .05). They recommended adoption of a flushing procedure which did not contain heparin.

Transcending Humiliation: An ancient perspective.

Drawing upon Ayurvedic teachings, this paper raises the possibility of transcending the humiliation dynamic through higher states of consciousness.

Gastrointestinal endoscopic polypectomy.

Recent advances in the field of gastroenterological endoscopy have now embraced endoscopic polypectomy. Experiences at the Royal North Shore Hospital over a period of one year include 42 colonic and three gastric polypectomies. Rectal bleeding was the main presenting feature in the patients with colonic polyps. All colonic polyps were situated between the sigmoid and transverse colon. Eighteen polyps were under 1 cm in size, 15 between 1 and 2 cm and nine over 2 cm. There was one carcinoma detected in each of these groups. No significant complications were encountered with any of these patients. The high yield of malignancy, none of which could be suspected on clinical or radiological grounds, more than justifies the introduction of this endoscopic procedure which will offer considerable saving from both the point of view of economic factors and personal discomfort.

Hyaluronidase and peribulbar block.

We have assessed the effect of two concentrations of hyaluronidase on the quality of peribulbar block, using a low volume, single injection technique. We studied 200 patients undergoing elective intraocular surgery, allocated randomly to one of three groups. Group 1 (n = 50) received peribulbar block with 5 ml of a 1:1 mixture of 0.5% plain bupivacaine and 2% plain lignocaine. Group 2 (n = 75) received this solution supplemented with hyaluronidase 50 iu ml-1. Group 3 (n = 75) received the same solution supplemented with hyaluronidase 300 iu ml-1. Lack of ocular motility was considered to be the only objective sign of successful block and movement of each rectus muscle was scored at 1-, 5- and 10-min intervals. If the block was successful at 5 min, the 10-min score was omitted. If the block was unsuccessful at 5 min, a second injection of 2% lignocaine 3 ml was given and additional assessments performed at 5-min intervals. At 1 min, ocular motility scores were significantly lower in group 3 compared with the control group (P < 0.05). The incidence of satisfactory block at 5 min was increased in both groups given hyaluronidase (group 2, P < 0.05; group 3, P < 0.001). There were no significant differences between groups 2 and 3 with respect to quality of block at 5 min. Hyaluronidase in both concentrations improved the quality of peribulbar block at 5 min, and when used in a concentration of 300 iu ml-1, also improved the speed of onset of block.

Chair dental anaesthesia: a survey of current and intended practice in Mersey Region.

We performed a questionnaire survey to establish the current and intended practice of chair dental anaesthesia amongst recently appointed consultants, and senior registrars within the Mersey Region. Only 26% of the consultants surveyed practised chair dental anaesthesia, however, more consultants would have had their anaesthetic sessions allowed. Consultants performed 4.62 +/- 3.5 sessions per month and anaesthetised 8.0 +/- 2.27 patients per session. Cases were mostly performed in community dental centres. The most common reason for discontinuing the practice of chair dental anaesthesia was the Poswillo report and its implications. Sixty-eight per cent of senior registrars declared an interest in chair dental anaesthesia. This group had received significantly more training (p < 0.005) in dental anaesthesia than those with no interest. Most anaesthetists (52/71) felt that chair dental anaesthesia was acceptable in centres approved to Poswillo standards; 16 anaesthetists felt that it should be confined to a hospital environment and three felt that it should not be performed at all.

Endurance exercise training in Guillain-Barre syndrome.

The purpose of this case study was to determine whether an individual who had residual deficits following an acute incidence of Guillain-Barre Syndrome (GBS) would experience improved physiological adaptations following aerobic endurance training. A 57-year-old man who needed the aid of a crutch for walking three years following an acute bout of GBS participated in this study. Peak work level (watts), oxygen consumption (VO2 mL/min; mL/kg.min), and ventilation (VE, L/min) were determined on a bicycle ergometer (BE), a Schwinn Air-Dyne ergometer (SAE), and an arm crank ergometer (ACE) before and after exercise training. Isokinetic leg strength measured using a dynamometer and total work capacity in watts using BE were also determined before and after training. The subject trained for 16 weeks at an approximate frequency of 3 days/week, an average duration of 30 minutes, and an average intensity of 75% to 80% of pretraining peak HR. A 9% and 11% improvement was seen in peak oxygen consumption for the SAE and BE, respectively. For peak ventilation, a 23% and 11% improvement was seen for the SAE and BE, respectively. For the ACE, a 16% increase in peak ventilation was seen, with no improvement in aerobic capacity. Total work capacity on the BE was improved by 29% following training. Positive improvements were also seen in isokinetic leg strength. This study demonstrated that a man still suffering residual symptoms following an incidence of GBS was able to improve his cardiopulmonary and work capacity and isokinetic strength of his legs following a supervised training program using the SAE. The subject also reported improvements in activities of daily living.

The accuracy of predicting treadmill VO2max for adults with mental retardation, with and without Down's syndrome, using ACSM gender- and activity-specific regression equations.

The purpose of this study was to examine the validity of the American College of Sports Medicine's (ACSM) prediction equations for calculating peak oxygen consumption (VO2max) in young adults with mental retardation. A total of 32 subjects with mental retardation participated in this study: 15 young adults with Down's syndrome (DS) and 17 non-DS young adults (NDS). Subjects were matched for age, gender and intelligence quotient (IQ). Subjects were given a standard treadmill-graded exercise test to determine peak heart rate (HR) and peak oxygen consumption (VO2max). Subjects were connected to a metabolic cart during the test. Peak VO2 was predicted using ACSM's prediction equations where predicted VO2max is: men, 57.8-0.445 (age); and women, 42.3-0.356 (age). Statistical significance between groups was determined using a two-tail t-test, with alpha set a priori at 0.05. The DS group had a significantly (P = 0.0003) lower peak HR (DS 155.90 +/- 12.12 vs NDS 175.38 +/- 9.87) and per cent HR achieved (P = 0.0007) (DS 80.26 +/- 6.76 vs NDS 89.39 +/- 4.46) as compared to the NDS group. Differences were also found between groups with respect to peak oxygen consumption. The DS had a significantly (P = 0.006) lower peak oxygen uptake (ml kg-1 min-1) as compared to the NDS group (23.68 +/- 4.01 vs 31.00 +/- 7.11, respectively). Significant differences (P = 0.007) were accordingly observed with respect to per cent predicted oxygen uptake achieved (DS 55.22 +/- 10.61 vs NDS 73.27 +/- 19.15). A nearly two-fold difference (P = 0.01) was observed with respect to the functional aerobic impairment between the DS (44.79 +/- 10.61) and NDS (28.29 +/- 18.63) groups, further illustrating the impaired peak cardiovascular capacities of both groups. The results of this study indicated that use of the ACSM gender and activity specific prediction equations in young adults with mental retardation (DS and NDS), peak VO2 is significantly over-predicted (83.9 and 39.2%, respectively). Therefore, peak oxygen consumption and derived exercise prescriptions must be based on actual measurements, rather than via ACSM prediction equations. Otherwise, training intensities may be over-predicted and impose possible health risks.

Isokinetic arm and leg strength of adults with Down syndrome: a comparative study.

This study compared isokinetic arm (elbow flexion and extension) and leg (knee flexion and extension) strength of individuals with Down syndrome (DS), with mental retardation without DS (NDS), and sedentary young adults with no mental retardation (NMR). Eighteen individuals with DS, NDS, and NMR (11 men and seven women in each group) performed strength tests on a Cybex 340 isokinetic dynamometer. Parameters measured were peak torque (ft/lb), peak torque percent body weight (%BW), average power (watts), and average power %BW. Subjects with mental retardation (ie, DS and NDS groups) performed the test on two separate days with best test results chosen for statistical comparisons. The NMR group performed the test once. In all isokinetic strength parameters measured for arm strength, the NMR group demonstrated significantly higher scores than subjects with DS and NDS. Subjects with DS and NDS displayed similar test results. Similarly, for all the isokinetic strength parameters measured for leg strength, NMR demonstrated significantly higher scores than subjects with DS and NDS. Subjects with NDS, however, averaged significantly higher test results than subjects with DS for leg strength. The results of this study indicate that both subject populations who were mentally retarded exhibited lower arm and leg strength than the NMR subjects. Additionally, subjects with DS demonstrated inferior leg strength when compared to their peers with NDS.

Comparison of the effects of topical lignocaine spray applied before or after induction of anaesthesia on the pressor response to direct laryngoscopy and intubation.

In an attempt to attenuate the cardiovascular pressor response to laryngoscopy and intubation, 30 patients presenting for routine ophthalmic surgery were studied and were randomly allocated into two groups: group A (n = 15) received direct laryngeal/tracheal lignocaine spray immediately before intubation; and group B (n = 15) received orolaryngeal lignocaine spray before the induction of anaesthesia. In both groups, general anaesthesia was induced with thiopentone 3-5 mg kg-1, followed by atracurium 0.6 mg kg-1 to facilitate tracheal intubation. Laryngoscopy and endotracheal intubation caused a significant increase in heart rate, by 28% in group A and 23% in group B (P < 0.05 in both), and in diastolic blood pressure, by 28% in group A and 24% in group B (P < 0.05 in both). In group A, the systolic blood pressure also increased significantly (by 18%) after intubation, but there was no significant change in group B. In addition, the plasma lignocaine concentrations remained well below the toxic range in both groups. It was concluded that topical lignocaine administration as an orolaryngeal spray before the induction of anaesthesia is effective in reducing but not abolishing the pressor response to laryngoscopy and endotracheal intubation.

Gastric candidiasis.

A male, aged 60 with rheumatoid arthritis which was treated with prednisone, developed a severe symptomatic stomal gastritis at the site of a previous Polya partial gastrectomy. The endoscopic appearance of the lesion was similar to that of Candida infection, which is more frequently seen in the oesophagus. Candida albicans was cultured from biopsy specimens, and prompt resolution of the lesion and the patient's symptoms occurred with orally administered antifungal therapy. Primary gastric candidiasis should be considered in compromised patients with symptoms of infection of the upper part of gastrointestinal tract.

Chronic erosive (verrucous) gastritis. A study of 108 patients.

Chronic erosive gastritis (C.E.G.) is a gastric mucosal lesionwith characteristic radiological and endoscopic appearances. Pyloric gland hyperplasia is seen on histological examination of biopsy specimens. C.E.G. is uncommonly reported in the English literature. In reviewing 3,800 upper gastro-intestinal endoscopies from 1971--1976, 108 patients were diagnosed as having typical features of chronic erosive gastritis, an incidence of 2.8%. There was a significant association with duodenal ulceration and an overall male predominance. The lesion can also co-exist with gastric ulceration and has been observed as an incidental finding in patients examined urgently for upper gastro-intestinal bleeding. In this context C.E.G. should be distinguished from acute mucosal erosions. Symptoms may relate to the accompanying peptic ulceration, although dyspepsia epigastric pain, fullness and nausea may possibly occur with C.E.G. alone.