Progressive effect of endurance training on VO2 kinetics at the onset of submaximal exercise

The rates of increase in O2 uptake (VO2) after step changes in work rate from 25 W to 60% of pretraining peak VO2 (VO2 peak) were measured at various times during an endurance training program (2 h/day at 60% pretraining VO2 peak). Seven untrained males [23 +/- 1 (SE) yr] performed a series of repeated step changes in work rate before training (PRE) and after 4 days (4D), 9 days (9D), and 30 days (30D) of training. VO2 kinetic responses were determined from breath-by-breath data averaged across four repetitions and analyzed using a two-component exponential model. Mean response time (time taken to reach 63% of steady-state VO2) was faster (P < 0.01) than PRE (38.1 +/- 2.6 s) at both 4D (34.9 +/- 2.4 s) and 9D (32.5 +/- 1.8 s) and was faster (P < 0.01) at 30D than at all other times (28.3 +/- 1.0 s). Blood lactate concentrations (after 6 min of cycling) were also lower at 4D and 9D than PRE (P < 0.01) and were lower at 30D than at all other times (P < 0.01). VO2 peak was unchanged from PRE (3.52 +/- 0.20 l/min) at 8D (3.55 +/- 0.20 l/min) but was increased (P < 0.01) at 30D (3.89 +/- 0.18 l/min). Muscle oxidative capacity (maximal citrate synthase activity) was not significantly increased until 30D (P < 0.01). It is concluded that at least part of the acceleration of whole body VO2 kinetics with endurance training is a rapid phenomenon, occurring before changes in VO2 peak and/or muscle oxidative potential.     

Interleukin-1 beta facilitates afferent sensory transmission in the primary somatosensory cortex of anesthetized rats

The effect of topical application of human recombinant interleukin-1 beta (IL-1) on afferent sensory transmission to the neurones in the primary somatosensory (SI) cortex was determined in anesthetized rats. Quantitative determination of the effect of IL-1 was made by generating post-stimulus time histograms of unit responses to the stimulation of receptive field. IL-1 (0.01, 0.1, 1.0 U) significantly facilitated afferent sensory transmission in SI cortical neurones (n = 22). IL-1-induced facilitation fully recovered by 60 min after drug. In control experiments (n = 10), saline solution containing 0.2 bovine serum albumin, used as a vehicle, did not affect afferent sensory transmission. Our results suggest that IL-1 may be involved in the processing of afferent sensory information in the SI cortex of rats.     

Energy balance in endurance-trained female cyclists and untrained controls

Reports of low energy intakes in trained female athletes imply they have an increased energetic efficiency. To address this question, we determined how energy balance was achieved in endurance-trained females cyclists and lean controls (n = 5 in each group). Daily energy expenditure was measured by using standardized physical activity protocols in a whole room calorimeter on two separate occasions: a cycling day and a noncycling day. Energy intake for weight maintenance was determined by a period of controlled feeding 5 days before and the day of each energy expenditure measurement. Energy balance was achieved in the cyclists on the cycling day while they consumed 2,900-3,000 kcal (their usual condition) and in controls on the noncycling day while they consumed 2,100-2,200 kcal (their usual condition). Total daily energy expenditure was not significantly different between the cyclists and controls on the noncycling day with both groups performing similar levels of activity. On the cycling day, daily energy expenditure was significantly greater in the cyclists vs. controls (P < 0.03) as a result of their greater amount of cycling activity. Components of daily energy expenditure, i.e., resting metabolic rate and thermic effect of food and activity (noncycling), were not significantly different between groups. Overall, we found no significant increase in the energetic efficiency of endurance-trained female cyclists compared with controls.     

Purification and characterization of a phagocytosis inducing factor: role in cell-substratum adherence

There is a wealth of evidence that nonsteroidal anti-inflammatory drugs (NSAIDs) can prevent colorectal cancer. In this article the role of cyclooxygenase 1 and 2, the principle target of NSAIDs, in the development of colorectal cancer is reviewed. Cyclooxygenase is constitutively expressed in normal colonic epithelium and surrounding stroma and could catalyse the generation of malondialdehyde which is a known mutagen and could initiate colorectal carcinogenesis. Mutation of APC which is an early genetic event leads to the expression of cyclooxygenase 2 which may prevents the appropriate apoptosis of mutant adenoma cells. Other proneoplastic effects of cyclooxygenase include changing the action of Transforming Growth Factor beta from anti-proliferative to pro-proliferative, reducing adherence to extracellular matrix, promotes metastasis and angiogenesis. These properties of cyclooxygenases suggest that inhibition of both isoforms may have important protective effects against colorectal cancer.     

Determination of potential migrants present in Nylon 'microwave and roasting bags' and migration into olive oil

Two groups of potential migrants were found in Nylon "microwave and roasting bags' (MRBs): volatile compounds were released at cooking temperatures and non-volatile compounds were extracted with methanol and/or water. A dynamic headspace system at 200 degrees C followed by gas chromatography (GC) coupled to mass spectrometry (MS) was used for determination of volatile compounds. Cyclopentanone (31.7 mg/bag), 2-cyclopentyl cyclopentanone (17.4 mg/bag), hexadecane (2.6 micrograms/bag), heptadecane (3.2 micrograms/bag), octadecane (3.0 micrograms/bag) and epsilon-caprolactam (5.0-35.5 mg/ bag) were the main volatile compounds present in the MRBs. High performance liquid chromatography (HPLC) and mass spectrometry were combined for identification and quantification of non-volatile compounds extracted with methanol (46.0 mg/bag). Nylon 6,6 cyclic monomer and cyclic oligomers up to the tetramer and Nylon 6 monomer and cyclic oligomers up to the octamer were identified and quantified, confirming that the plastic was made of Nylon 6,6 and Nylon 6 polymers. The same non-volatile compounds (except Nylon 6 heptamer and octamer) were found to migrate into olive oil at 175 degrees C for 1 h. A total of 0.916 mg/dm2 (19.2 mg/bag) of non-volatile compounds migrated into olive oil (41.8% of those quantified in the plastic material).     

Fibrinolytic therapy of acute cerebral infarct

On the basis of our upon own results of local intra-arterial fibrinolysis (LIF), this article gives a short overview of recently established thrombolytic therapy in acute ischemic stroke. Fifty patients with acute occlusions of vertebrobasilar arteries and 118 patients showing occlusions of branches of the internal carotid artery were treated with LIF. The Occlusion type, occlusion site and successful recanalization were associated with a favorable outcome: 92% of embolic occlusions in the vertebrobasilar territory were recanalized and resulted in 50% in a favorable outcome. In the carotid territory, optimal outcome was achieved in main stem and branch occlusions of the middle cerebral artery, due to recanalization rates of 49%-64%. In contrast, occlusions of the intracranial bifurcation of the carotid artery (carotid-"T") resulted in death in 59%. Despite the lack of randomized trials, LIF is an established form of therapy in the vertebrobasilar territory. In the carotid territory randomized clinical studies could demonstrate the efficacy of intravenous fibrinolytic therapy in some stroke patients. It can be presumed from pilot studies that LIF is superior to the intravenous version in the carotid territory.     

Is the common 677C-->T mutation in the methylenetetrahydrofolate reductase gene a risk factor for neural tube defects? A meta-analysis

In both jurisdiction and medical science, given conditions require appropriate intervention, which may in turn result in norms being created. Norms, however, counteract individuality. An essential prerequisite for free decision--making is an absolute awareness of all possibilities available. Therefore the physician/surgeon too, is obliged to impart all relevant information to the patient prior to an operation to enable the patient to reach a decision, either to agree to or refuse the operation. This process of information transfer may sometimes fail on one or both sides. Treatment errors are usually classified according to scientific medical practice. In the case of "breach to duty in information patient" the final decision is the judges. As judicial decisions are not foreseeable, the communication between patient and surgeon thus becomes standardized and doctors tend to become defensive, resulting in the information becoming even more extensive covering all possible situations. There is no guarantee of success in surgery. Selective perception on the part of the patient is unavoidable and confidence in the relationship between patient and surgeon is beneficial to the patient's rehabilitation. Therefore, we should strive to decriminalize the preoperative talk held between surgeon and patient.     

Streptococcal preseptal cellulitis complicated by the toxic Streptococcus syndrome

BACKGROUND: After decades of decline in the incidence of severe infections secondary to group A streptococci, a dramatic increase in the frequency and severity of infections with these organisms has been reported since 1984, including a "toxic Streptococcus syndrome," resembling staphylococcal toxic shock syndrome. To the authors' knowledge, this entity has never been described after ocular infection. METHODS: In a previously healthy 3-year-old boy, preseptal cellulitis developed secondary to minor trauma to the eyelid, progressing rapidly to hypotension, respiratory distress, and an erythrodermic desquamating rash. Ocular and blood cultures grew group A beta-hemolytic streptococci. Appropriate antibiotic coverage and management of systemic manifestations led to rapid improvement, although necrosis developed in the right upper anterior eyelid, requiring skin grafts. RESULTS: More than 3 years since the incident, the patient is free of infection and has a good cosmetic result after skin grafting and revisions for scarring and adhesions. CONCLUSIONS: Streptococcal preseptal cellulitis is not unusual, particularly after trauma. Ophthalmologists must be aware of the re-emergence of more virulent organisms with increased potential for morbidity and mortality.