Load carriage physiology in normoxia and hypoxia

PURPOSE

To determine the effects of load carriage in normoxia and normobaric hypoxia on ventilatory responses, hemodynamics, tissue oxygenation, and metabolism.

METHODS

Healthy males (n = 12) completed 3 randomly ordered baseline graded exercise tests in the following conditions: (1) unloaded normoxic (U: FIO2 = 20.93%), (2) loaded (~ 30 kg) normoxic (LN), and (3) loaded hypoxic simulating ~ 3650 m (LH: FIO2 =  ~ 13%). Thereafter, experimental exercise trials were completed in quasi-randomized order (i.e., U completed first) consisting of 3 × 10 min of walking (separated by 5 min seated rest) with stages matched with the U condition (in ascending order) for relative intensity, absolute oxygen consumption ([VO2]; 1.7 L min-1), and walking speed (1.45 ± 0.15 m s-1).

RESULTS

Load carriage increased perceived exertion and reduced VO2max (LN: - 7%; LH: - 32%; p < 0.05). At matched VO2, stroke volume and tidal volume were reduced and maintained with LN and LH vs. U, respectively (p < 0.05). Increases in cardiac output and minute ventilation at matched VO2 (with LH) and speed (with LN and LH), were primarily accomplished via increases in heart rate and breathing frequency (p < 0.05). Cerebral oxygenated hemoglobin (O2HHb) was increased at all intensities with LN, but deoxygenated hemoglobin and total hemoglobin were increased with LH (p < 0.05). Muscle oxygen kinetics and substrate utilization were similar between LN and U, but LH increased CHO dependence and reduced muscle O2HHb at matched speed (p < 0.05).

CONCLUSION

Load carriage reduces cardiorespiratory efficiency and increases physiological strain, particularly in hypoxic environments. Potential load carriage-induced alterations in cerebral blood flow may increase the risk for altitude illnesses and requires further study.

Rational molecular design enhancing the photonic performance of red-emitting perylene bisimide dyes

We report the synthesis of novel multichromophoric organic architectures, where perylene red is decorated with BODIPY and/or hydroxycoumarin dyes acting as light harvesters and energy donors. The computationally-aided photophysical study of these molecular assemblies reveals a broadband absorption which, regardless of the excitation wavelength, leads solely to a bright red-edge emission from perylene bisimide after efficient intramolecular energy transfer hops. The increase of the absorbance of these molecular antennas at key pumping wavelengths enhances the laser action of the commercial perylene red. The herein applied strategy based on energy transfer dye lasers should boost the use of perylene-based dyes as active media for red-emitting lasers.

Coumarin-BODIPY hybrids by heteroatom linkage: versatile, tunable and photostable dye lasers for UV irradiation

Linking amino and hydroxycoumarins to BODIPYs through the amino or hydroxyl group lets the easy construction of unprecedented photostable coumarin-BODIPY hybrids with broadened and enhanced absorption in the UV spectral region, and outstanding wavelength-tunable laser action within the green-to-red spectral region (∼520-680 nm). These laser dyes allow the generation of a valuable tunable UV (∼260-350 nm) laser source by frequency doubling, which is essential to study accurately the photochemistry of biological molecules under solar irradiation. The tunability is achieved by selecting the substitution pattern of the hybrid. Key factors are the linking heteroatom (nitrogen vs. oxygen), the number of coumarin units joined to the BODIPY framework and the involved linking positions.

Health related quality of life and late side effects of long-term survivors of Ewing's sarcoma of bone

PURPOSE

The data examining the Health Related Quality of Life (HRQOL) after definitive treatment for Ewing's sarcoma (EWS) is sparse. The objective of this study was to assess the HRQOL and late side effects in EWS of bone survivors treated in the past 2 decades.

METHODS

Seventeen long-term (≥ 5 years) EWS survivors (age range, 11-27 years) treated from 1990 to 2004 completed the EORTC-QLQ-C30. We compared the HRQOL of our data set with a reference group of cancer survivors and also with the general population. Musculoskeletal late treatment toxicity was also evaluated. The Mann-Whitney and Wilcoxon tests were used for analyses.

RESULTS

EWS survivors of our series reported significantly better global, physical, role and cognitive HRQOL and less symptoms of fatigue, pain and insomnia than the normative sample of cancer survivors. Moreover, the HRQOL was equivalent to the general population, with the exception of social functioning. Additionally, patients with tumor location in the extremities did not report significant HRQOL differences compared with those with tumor at other locations. Common chronic grade 2 side effects were generalized muscle weakness (23%) and decreased joint range of motion (23%). Only one patient experienced musculoskeletal chronic grade 3 toxicity.

CONCLUSION

Our findings suggest that EWS survivors treated in the modern era do not experience lower HRQOL than other cancer survivors. Rather, the HRQOL appears to be equivalent to the general population. Further and larger studies are needed to confirm these results.

Diagnóstico de recurrencia mediante FDG-PET en un caso clínico de schwannoma maligno

The peripheral nerve sarcoma, also called malignant schwannoma, is originally a soft tissue sarcoma. It is mainly located in the peripheral sheath nerve of the limbs and usually infiltrates the nerve fibres. We present the case of a thirty year old woman with a malignant schwannoma in her left leg sciatic nerve who had been treated on several occasions. An 18-FDG positron emission tomography was performed to evaluate the management of the patient. It showed regional recurrence, which required leg amputation. The pathological result has confirmed the PET diagnosis. PET can be a useful technique to detect recurrence for this kind of tumor, mainly in patients who have been previously radiated when the MRI is insufficient to perform a differential diagnosis between postirradiation fibrosis and tumoral recurrence, allowing for suitable therapeutic management of the patient.

Prolactin and interleukin-6 in neuropsychiatric lupus erythematosus

We investigated the levels of prolactin (PRL) and interleukin-6 (IL-6) in the cerebrospinal fluid (CSF) and serum of systemic lupus erythematosus patients with central nervous system involvement (CNS-SLE), and examined whether PRL and IL-6 have a relationship. Serum and CSF PRL and IL-6 were measured in the following groups of patients and controls: group I: seven patients with CNS-SLE; group II: three SLE patients without CNS involvement (non CNS-SLE); group III: 10 patients with neurocysticercosis; and group IV: six healthy women. The patients were clinically assessed. CSF PRL and IL-6 were elevated in group I (CNS-SLE) in comparison with all other groups (p<0.001). In addition, four of seven patients had higher levels of IL-6 and PRL in CSF than in serum. A positive correlation between PRL and IL-6 in CSF of SLE was observed (r=0.88, p<0.001). The mean serum PRL concentrations were not significantly different in all groups, but high levels of IL-6 were found in the serum of group I in comparison with groups II and IV (p<0.001). The serum levels of group III were not different from those of group I. These results demonstrate the presence of intrathecal synthesis and elevations of CSF PRL and IL-6 in active CNS-SLE involvement and indicate that measurements of CSF PRL and IL-6 may be useful in the evaluation of neuropsychiatric lupus erythematosus.

[Biplane transesophageal echocardiography. Experience with 130 outpatients]

PURPOSE

To analyse the utility of transesophageal echocardiography (TEE) as a complementary technique to transthoracic echocardiographic (TTE) comparing results and additional informations.

METHODS

One hundred and thirty consecutive outpatients (66 male) submitted to TEE, with age ranging from 12 to 84 years were studied. Patients were grouped according to the main indication: evaluation of prosthetic valves, 21 patients; cardiac source of emboli, 43; diseases of the aorta, 17; infective endocarditis, 14; congenital heart diseases, 14 and other abnormalities in 21 patients.

RESULTS

TEE provided additional and important information in all groups. Perivalvular leakage was observed in 42.1% of patients with prosthetic valves. Vegetations were detected in 45.5% of the suspected cases of endocarditis (missed by TTE). Dissection of aorta was diagnosed in 35.2% of patients with suspected disease and atrial septal defect was successfully recognized in 80% of the cases. No complications were observed.

CONCLUSION

TEE is a safe and usefull complementary non-invasive diagnostic tool in the assessment of structures such as left atrium, left atrial appendage, thoracic aorta, prosthetic valves and in the investigation of infective endocarditis.

Heterotopic gastric mucosa of the tongue

A cyst of the tongue lined by gastric mucosa is described, and eight previously reported cases are reviewed. All the patients with heterotopic gastric mucosa of the tongue have been males whose ages range from 2 months to 31 years, the sole exception being our case in a newborn infant. Six lesions were cystic and three were solid. Five were located on the anterior one-third of the tongue, three at the base, and one at the tip. Conservative excision is the procedure of choice, and of the patients reviewed, only our patient required a second excision. No additional abnormalities have been reported in these patients, except for one patient who had a double upper lip.