Cognitive function following long-term spinal cord injury.

Although age-related changes in cognition are well documented, little is known about the effect of chronic disability on memory performance. This study investigated age differences between younger and elderly adults with long-term spinal cord injury, using a variety of measures of memory and self-assessments of cognitive abilities. Advanced age was associated with poorer memory performance, but neither level of injury on the spinal cord (cervical versus thoracolumbar lesions) nor duration of the injury predicted memory test scores. The two age groups were similar in their self-ratings of many attentional and memory abilities, as well as activity and affective level, consistent with good adjustment over long periods of disability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dynamic changes in intracapillary hemoglobin oxygenation in human skin following various temperature changes

Modulation of Fas expression and function by CD40 ligation was investigated in the Fas-sensitive human Hodgkin's disease cell line HDLM2. The recombinant human trimeric soluble CD40L (sCD40L) protected this cell line from apoptosis induced by an agonistic Fas antibody at all concentrations tested. sCD40L also protected HDLM2 when added up to 2 h after Fas ligation. Apoptosis induced by a cell-permeable synthetic ceramide could not be prevented by sCD40L. Thus, CD40 ligation is likely to intervene in the early phases of the Fas signal transduction pathway. When CD40 ligation preceded Fas ligation, it rendered the cells refractory to Fas-induced apoptosis. sCD40L-mediated protection could not be attributed to reduction in surface Fas expression, increase in Bcl-2 levels or to increase in the levels of soluble Fas isoforms.     

The pathophysiologic changes following bile aspiration in a porcine lung model

Aspiration of bile is an underpublicized aspiration syndrome. Using a porcine lung model, the physiologic response and the histopathology of lung tissue were evaluated after the intratracheal instillation of sublethal doses of bile. Twenty-one domestic swine (11 to 19 kg) were the studied population. Three groups of five swine were evaluated: a control group received intratracheal physiologic saline (pH 7.45); study group 1 received strained gastric contents (pH 2.24); and study group 2 received strained bile (pH 7.19). All animals received the solutions at 0.5 ml/kg intratracheally. Lungs of six additional animals were studied (two gastric, two bile, and two physiologic saline) after aspiration by scanning electron microscopy (SEM). A seventh untreated animal was used as the SEM control. The physiologic data were analyzed using analysis of variance for repeated measures. The SEM and histopathologic results were graded by an observer blinded to the groups and were analyzed using the analysis of variance (ANOVA) and Scheffe tests. The group with bile aspiration was consistently characterized by significant deterioration of PaO2, the alveolar-arterial (A-a) gradient, shunt fraction, and static compliance (p < 0.01); and the light histopathologic and SEM findings demonstrated pathologic changes in the bile-exposed lung (p < 0.05) greater than the gastric- or saline-exposed lungs. It is concluded that bile aspiration produces a severe chemical pneumonitis leading to noncardiac pulmonary edema.     

Longitudinal changes in lung function associated with aspects of swine-confinement exposure

Several aspects of swine-confinement farming appear to be leading to adverse respiratory effects. This study was set up in a longitudinal design to study the association between certain characteristics of farms or the way they are run and a decline in lung function. A cohort of 171 pig farmers was observed for 3 years. Lung function was measured. Exposure to farm characteristics was determined at the start of the observation period, using data from standardized farm surveys and from diaries kept by the participants. Mean decline in lung function was 73 mL/year for forced expiratory volume in 1 second (FEV1) and 55 mL/year for forced vital capacity (FVC). A longitudinal decline in FEV1 was significantly associated with the use of quaternary ammonium compounds as disinfectants (an additional 43 mL/year) and also with the use of an automated dry feeding system (an additional 28 mL/year). The association with the use of wood shavings as bedding material was not statistically significant. The impact of these characteristics in a longitudinal study provides stronger evidence for causal inference than that shown in previous cross-sectional designs. This may be useful in promoting preventive measures.     

Human acclimation to work in warm and humid environments

The aim of this study was to analyse the acclimation of male Europeans during a forty-one day stay in the hot and humid climate of Thailand. We also tried to examine the phases of acclimation which would eventually be used by trainers in the elaboration of the schedule of athletes' preparation to participate in competitions in a tropical climate. Twelve Polish male subjects ageing 21-38 years participated in these examinations. In Poland and Thailand the cycloergometric exercise test with the load of 53% of VO2max was performed until a 1.2 degrees C (delta Tre) increase in rectal temperature was reached. The exercise test was executed in the same environmental conditions (i.e. 30 +/- 1 degrees C and 70 +/- 3% of relative humidity). The duration of this exercise test (DE) was used as a criterion for the efficiency of thermoregulatory functions. During acclimation, three peaks of greater exercise thermoregulatory efficiency have been found, i.e. on the 4th-5th, 11th-12th and 29th-30th days of stay. These findings are particularly important for professional athletes who wish to prepare themselves for competitions held in hot and humid climates.     

Physical and biological predictors of changes in whole-lung function following thoracic irradiation

PURPOSE: To develop methods of predicting the pulmonary consequences of thoracic irradiation (RT) by prospectively studying changes in pulmonary function following RT. METHODS AND MATERIALS: 100 patients receiving incidental partial-lung irradiation during treatment of tumors in or adjacent to the thorax had whole-lung function assessed via symptoms and pulmonary function tests (PFTs: FEV1-forced expiratory volume 1 s; DLCO-diffusion capacity) before and repeatedly 6-48 months following RT. All had computed tomography-based three-dimensional (3D) dose calculations with lung density heterogeneity corrections for dose-volume histogram (DVH) and normal tissue complication probability (NTCP) calculations. Functional DVHs (DVfH) based on SPECT (single photon emission computed tomography) lung perfusion scans, and serial transforming growth factor-beta (TGF-beta1) levels were available in 50 and 48 patients, respectively. The incidence and severity of changes in whole-lung function were correlated with clinical, physical, and biological factors. Exploratory statistical analyses were performed using chi-square, Pearson correlations, logistic regression, and multiple linear regression. RESULTS: RT-induced symptoms developed in 21 patients. In the overall group, the single best predictor for the development of symptoms was the NTCP (p < 0.05). Pre-RT PFTs alone were less predictive (p = 0.1 for FEV1, p = 0.08 for DLCO). A multivariate model based on pre-RT DLCO and CT-based NTCP was strongly predictive for the development of symptoms (p < 0.001). NTCPs based on SPECT-derived DVf Hs and TGF-beta1 levels did not appear to provide additional predictive value. The presence or absence of pulmonary symptoms was correlated with the decline in PFT 6 months following RT (p < 0.05). In the overall group, the degree of decline in PFTs was not well correlated with any of the dose-volume variables considered. In patients with "good" pre-RT PFTs, there was a relationship between the percent reduction in PFT and dose-volume parameters such as the percent of lung volume receiving > 30 Gy (p < 0.05). CONCLUSION: The extent of alteration in whole-lung function (symptoms or PFT changes) appears to be related to both dose-volume and pre-RT PFT parameters. The data suggest that no one variable is likely to be an adequate predictor and that multivariate predictive models will be needed. Additional studies are underway to develop better predictive models that consider physical factors such as the DVH and regional perfusion, as well as biological/clinical factors such as pre-RT PFTs and TGF-beta1.     

Improved lung function and quality of life following increased elastic recoil after lung volume reduction surgery in emphysema

OBJECTIVES: To investigate whether tumor volume, an important prognostic factor in prostate cancer, could be estimated from the amount of cancer in multiple core biopsies. METHODS: In 80 men, transrectal ultrasound-guided biopsies were taken from focal lesions detected by ultrasound and 8 to 10 standardized positions, including sextant biopsies (apex, midmedial, base) and midlateral and transition zone biopsies. The cancer length in the biopsies was measured. After radical prostatectomy, the prostates were totally embedded, whole-mounted, and tumor volume was measured planimetrically. RESULTS: The tumor volume correlated significantly with the total cancer length of all biopsies (r = 0.56) and of the sextant biopsies (r = 0.39). It was found that midlateral and transition zone biopsies provided independent information when included in a multiple regression model with tumor volume as the dependent variable and the sextant biopsies as explanatory variables. All men (n = 6) with less than 3 mm cancer length in only one positive biopsy and a Gleason score less than 7 had a tumor volume less than 1 mL. Nine of 10 men with less than 7 mm of cancer in one positive biopsy and Gleason score less than 7 had tumors smaller than 1 mL. Sextant biopsies did not reliably predict cancer volumes less than 1 mL. CONCLUSIONS: The cancer yield of 8 to 10 biopsies correlated better with the volume of prostate cancer than sextant biopsies. This extended biopsy protocol could be used to predict cancers of less than 1 mL in volume.     

Relationship between lung inflammation, changes in lung function and severity of exposure in victims of the Bhopal tragedy

The world's worst chemical industrial disaster, which occurred at Bhopal on 2-3 December, 1984, resulted in considerable respiratory morbidity in the exposed population. Therefore, a study was planned to evaluate the relationship between lower respiratory tract inflammation, lung function and severity of exposure. Sixty patients exposed to methyl isocyanate and presenting with respiratory symptoms were studied using bronchoalveolar lavage (BAL) 1-7 yrs after the accident. Pulmonary function tests included forced vital capacity (FVC) and forced expiratory volume in one second (FEV1). An index of severity of exposure was derived retrospectively on the basis of the acute symptoms in the victims themselves or the occurrence of death among their family members. Total lung inflammatory cells (p < 0.01) and absolute numbers of macrophages (p = 0.01) and lymphocytes (p < 0.05) increased as severity of exposure increased. FEV1/FVC % (p = 0.05) was also significantly lower as severity of exposure increased. Moderately exposed subjects had significantly lower FEV1/FVC % (p < 0.05) compared to those mildly exposed. In nonsmokers, BAL neutrophils, both percentage and absolute numbers, showed significant negative correlations with FEV1 % predicted (rs = -0.350, p < 0.05; and rs = -0.374, p < 0.01, respectively). Neutrophil percentage was negatively correlated with FEV1/FVC % (rs = -0.378; p < 0.01). Absolute lymphocytes had significant negative correlations with FVC % pred (rs = -0.318; p < 0.05). Macrophages had significant positive correlations with FVC % pred (rs = 0.322; p < 0.05) and FEV1 % pred (rs = 0.433; p < 0.01). Radiographic abnormalities (International Labour Organization (ILO) classification) were associated with decline in FEV1 % pred (p < 0.05). This study suggests that pulmonary function abnormalities occur in gas-exposed subjects as a consequence of an abnormal accumulation of lung inflammatory cells (lymphocytes and neutrophils), and that the intensity of lung inflammation and reduction in pulmonary function are greater in severely exposed subjects. As it has been observed that decline in pulmonary function is associated with radiographic abnormalities, there is a suggestion that injury following toxic gas exposure can lead to irreversible lung damage.     

Kidney morphological changes in relation to long-term renal function and metabolic control in adolescents with IDDM

OBJECTIVE: To investigate the impact of HIV infection on the prevalence, incidence and short-term prognosis of squamous intraepithelial lesions (SIL), in a prospective study with 1-year follow-up. METHODS: Between 1993 and 1995, 271 HIV-positive and 171 HIV-negative women at high risk of HIV infection were recruited, 365 (82.6%) of whom completed the 1-year follow-up. The women underwent a Papanicolaou smear test at inclusion and at 6 and 12 months. Human papillomavirus (HPV) was detected at inclusion by Southern blot and PCR. RESULTS: The SIL prevalence ranged from 7.5% for HIV-negative to 31.3% for HIV-positive women with CD4 cell counts < 500 x 10(6)/l (P < 0.001). Other factors associated independently and significantly with SIL prevalence were HPV-16, 18, 33 and related types, HPV-31, -35, -39 and related types, lifetime number of partners, younger age, past history of SIL and lack of past cervical screening. The SIL incidence ranged from 4.9% in HIV-negative women to 27% in HIV-positive women with CD4 cells < 500 x 10(6)/l (P < 0.001). Progression from low- to high-grade SIL during follow-up was detected in 38.1% of HIV-positive women with CD4 cells < or = 500 x 10(6)/l but in no HIV-negative nor HIV-positive women with CD4 cells > 500 x 10(6)/l. HPV-16, 18, 33 and related types were also associated with higher incidence of SIL and progression from low- to high-grade SIL. CONCLUSION: HIV-induced immunodeficiency is associated with high prevalence, incidence and persistence/progression of SIL. A pejorative influence of HIV infection without marked immunodeficiency is less clear. HIV-positive women with SIL may thus benefit from early treatment when a useful immune response is still present.     

Relationship between external resistances, lung function changes and maximal exercise capacity

In upper airway obstruction (UAO) the relationship between the degree of obstruction, exercise limitation and lung function indices is not well established. Therefore, we investigated in nine healthy subjects (age 36+/-9 yrs) the effects of two added resistances at the mouth (R1 = added resistance with 7.8 mm diameter; R2 = 5.7 mm) on forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), airway resistance (Raw) and maximal breathing capacity (measured during 15 s = measured maximum breathing capacity (MBCm); calculated as FEV1x37.5 = calculated maximum breathing capacity (MBCc)) on the one hand, and maximum exercise capacity (W'max), minute ventilation (V'E) and CO2 elimination (V'CO2) on the other. We found that R1 had almost no influence on FEV1 but decreased PEF by approximately 35% and increased Raw by almost 300%; it decreased W'max by merely approximately 10% while maximal exercise ventilation (V'Emax) was only 65% of control and only reached approximately 40% MBCc and approximately 70% MBCm; yet V'E and V'CO2 were significantly reduced at high exercise levels indicating hypoventilation. With R2, FEV1 was reduced by 25% and PEF by 55%, and Raw was increased by 600%; W'max was approximately 60% of control, V'Emax was only 35% of control and reached approximately 30% MBCc and approximately 60% MBCm, V'E was already reduced at moderate exercise levels. We conclude that: 1) an upper airway obstruction of 6 mm diameter (but not of 8 mm) had a marked influence on maximum exercise capacity due to hypoventilation; 2) calculated maximum breathing capacity markedly overestimated measured maximum breathing capacity because the forced expiratory volume in one second is an insensitive index of upper airway obstruction and because it does not take inspiratory flow limitation into account; and 3) a 10% decrease in maximum exercise capacity was linearly related with a 7% decrease in the forced expiratory volume in one second and a 150% increase in airway resistance. A 10% decrease in maximal exercise ventilation was related to a 8.5% decrease in peak expiratory flow and 9% decrease in measured maximum breathing capacity.     

Effects of immersion in water and changes in intrathoracic blood volume on lung function in man

1. In healthy, normal subjects simultaneous peripheral venous occlusion of all four limbs caused a small but significant increase in vital capacity (VC) and single-breath carbon monoxide transfer factor (DLCO) without significantly changing total lung capacity (TLC), residual volume (RV), pulmonary gas flow or pulmonary compliance. 2. Immersion in water to the neck resulted in a small but significant fall in VC, FEV 1.0/FVC and TLC, and a rise in DLCO, but flow/volume curves and 'closing volume' were unchanged. Peripheral venous occlusion during immersion only significantly increased VC and DLCO; pulmonary compliance and flow/volume curves did not alter significantly. 3. It is concluded that peripheral venous occlusion produces these effects by altering intrathoracic blood volume. Water immersion reduces TLC, mainly from the hydrostatic pressure, and VC is reduced from both the hydrostatic pressure and the increase in intrathoracic blood volume consequent on immersion. The increase in DLCO is due, almost entirely, to the increase in intrathoracic blood volume.     

Cannabis and motor function: fMRI changes following 28 days of discontinuation.

The authors hypothesized that supplementary motor cortex (SMA) and anterior cingulate cortex (ACC) activation in chronic cannabis users, studied 4 to 36 hours after their last episode of use, would disappear by Day 28 of abstinence during finger-tapping tests. Eleven cannabis users and 16 comparison subjects were scanned during right (RFT) and left (LFT) finger-tapping tasks on a GE 1.5 Tesla scanner retrofitted with a whole body echo planar coil. Image analyses were conducted in SPM99 using an ROI approach to define each Brodmann area (BA). Differences in cerebral activation were examined in the left and right primary motor cortex (BA4), SMA (BA6), and ACC (BA24 and BA32 separately). The authors found diminished activation for contralateral BA6 from Day 0 to Day 28. For LFT, the authors also found: ipsilaterally diminished BA6 activation on Day 7, but not Day 0 or Day 28; ipsilaterally diminished BA32 activation on Day 0, but not Day 7 or Day 28; contralaterally diminished BA 4 activation on Day 28, but not Day 0 or Day 7; and contralaterally diminished BA32 activation on Day 0 and Day 28, but not Day 7. For RFT, the authors found ipsilaterally diminished BA32 activation on Days 0 and 7 but not on Day 28; contralaterally diminished BA32 activation on Days 0, 7, and 28; and ipsilaterally diminished BA6 activation on Days 0, 7, and 28. These results suggest that residual diminished brain activation is still observed after discontinuing cannabis use in motor cortical circuits. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dynamic changes in the reactivity of the hormonal system regulation with the impact by LBNP sessions in long-term space mission

Experiment INTERSTITIUM was performed on days 3, 170, 287, and 430 of the long-term MIR mission of the Russian cosmonaut-physician in order to evaluate reactivity of the system of hormonal regulation of homeostasis during LBNP sessions. Data of the experiment displayed different types of reaction of the volume controls to LBNP at the onset (F-3), in the course of and soon after recovery (R-4) from the extended mission which are signs of specific phases of adaptive shifts in the organism of cosmonaut. Exaggerated reactivity of the hormonal systems during LBNP in flight suggests more significant consequences of the test for the cardiovascular system of human in microgravity. The most expressed hormonal reaction to LBNP was documented at the very beginning of the postflight period. Plasma cGMP was materially reduced in the process of the mission and remained quite low on R-4; return of nucleotides to the norm was observed no earlier than on R-90. Complete recovery from the space mission took three months when the hormonal reaction to LBNP was same as prior to launch.     

The teleradiology system and changes in work practices

Five minutes of global ischemia in gerbil results in delayed hippocampal CA1 neuronal degeneration, which is accompanied by working memory impairments and hyperactivity in novel environments. In this study, postischemic activity was characterized in familiar and in novel environments to determine whether hyperactivity was due to impaired spatial habituation or another form of motor hyperactivity. This study also determined whether 6-h delayed hypothermia, which reduces CA1 neuronal injury, would attenuate functional impairments. Gerbils were subjected to 5 min of normothermic ischemia or sham operation 2 days following implantation of brain temperature probes. One of two ischemic groups was cooled (>48 h) starting at 6-h postischemia. Locomotor activity in a familiar cage was measured for 6 days while activity in three novel environments was intermittently measured on days 4, 5 and 6. Open field behavior and working memory in a T-maze were also assessed. Untreated ischemia caused marked hyperactivity in the familiar cage on day 1, which reverted to near-normal by day 2. Nonetheless, these gerbils showed hyperactivity during novel environment sessions on days 4-6. This maze behavior, which predicted hippocampal CA1 injury, was not due to different habituation rates nor baseline hyperactivity. Conversely, open field sessions on day 8 revealed ischemic habituation rate deficits. Ischemia also impaired working memory in the T-maze. Delayed hypothermia, which reduced neuronal loss in the CA1 sector to 12% from 81%, reduced all functional impairments. Ischemic gerbils quickly developed spontaneous locomotion hyperactivity that returned to near-normal after 1 day. This motor hyperactivity did not explain the elevated activity found with delayed testing in novel environments. Regardless, only the open field test on day 8 revealed a habituation-like deficit.     

Pathophysiology of changes in absolute lung volumes

Changes in absolute lung volumes are common in lung disease and result in significant impacts on gas exchange, respiratory muscle function, the sensation of dyspnoea, and limitations to maximal exercise. Though our knowledge regarding the magnitude and determinants of changes in lung volumes in health and disease has increased in the past 20 years, a number of important questions remain unanswered. Consideration of the limitations of specific methods for measuring lung volumes is essential when analysing published studies regarding absolute lung volumes in infants, children and adults. Though functional residual capacity is most commonly measured in children and adults with the subject awake and at rest, increasingly attention is being directed to making these measurements under clinically more relevant conditions (e.g. during exercise, sleep, anesthesia, or mechanical ventilation). The relationships between dynamic changes in functional residual capacity, flow limitation during tidal breaths, sensation of dyspnoea and exercise limitation are important to understand, and are the focus of current and future research. Improved understanding of these relationships may lead to improvements in therapy of patients with acute and chronic lung disease and are likely to be particularly important for evaluating the efficacy of and optimal patient selection for new modes of therapy, such as lung volume reduction surgery.     

Urinary changes in patients following restorative proctocolectomy

Following restorative proctocolectomy, the physiological function of the large intestine to absorb water and electrolytes is lost. Therefore, the kidney plays an important role in adjusting the water and electrolyte balance along with the ileal pouch. The reservoir function of the ileal pouch, however, may affect the functional adaptation of urinary changes. To observe the functional adaptation of urinary changes in ileal pouch patients, their changes in urinary output and electrolytes were investigated. Urinary output, pH, and electrolytes were all measured at 1 month, 6 months, and 1 year after surgery in patients with a J-pouch (n = 30) and compared with those in patients who had undergone ileostomy (n = 11) and healthy controls (n = 22). In the patients with a J-pouch, the urinary output, pH, and sodium concentration were significantly lower than those of the controls at 1 month after the operation. However, they gradually increased to near the control values at 1 year. In patients with an ileostomy, the urinary output, pH, and sodium concentration were lower than the control values up to 1 year postoperatively, but the urinary uric acid concentration was higher than that in the controls in both groups up to 1 year. The patients who had persistent aciduria were given a citrate mixture (3g/day), which effectively normalized the aciduria and also possibly prevented urinary uric acid stone formation.     

Effects of early environments on monkey cortex neuroanatomical changes following somatomotor experience: Effects on layer III pyramidal cells in monkey cortex.

Sixteen infant stumptail monkeys were reared to 6 months under four conditions. Behaviors and cortical neuroanatomy were compared. Earlier studies showed effects on stellate cell dendrites. Here are reported the results in six cortical areas on basilar dendrites of layer III pyramidal cells. Basilar dendrites show significantly larger numbers (p?