Biomedical subjects

A Velarde

Publications and source records attributed to A Velarde.

7 recordsLinked to original sources

PubMed2002

Nasal lavage concentrations of free hemoglobin as a marker of microepistaxis during nasal provocation testing.

BACKGROUND: The constituents of nasal mucus may be contaminated by plasma if there is epistaxis. Gross epistaxis is apparent as a red lavage fluid, while microepistaxis may yield a clear fluid. If gross or microepistaxis are present, it will be difficult to decide whether plasma protein concentrations are elevated because of plasma exudation or bleeding. In order to discriminate between these two possibilities, we measured erythrocyte-derived free hemoglobin (fHb) in nasal lavage fluids. METHODS: Single-blinded subjects underwent standard hypertonic saline nasal provocation. Unilateral hypertonic nasal provocation was performed in normal, allergic rhinitis (AR) and nonallergic rhinitis (NAR) subjects (total of 1316 specimens). fHb was measured using the Sigma-Aldrich kit (St. Louis, MO). Grossly bloody specimens were analyzed separately from the remainder. Statistical analysis defined the means and 95th percentiles for fHb and albumin in the nonbloody normal group. RESULTS: fHb concentrations ranged from below the limits of detection (< 1 microg/ml) to > 164 microg/ml fHb was 79.3 microg/ml +/- 4.7 (mean +/- SEM) in four normal, 31 AR and 25 NAR grossly bloody specimens. The 95th percentile of fHb in the nonbloody normal samples (n = 68 subjects, n = 681 specimens) was 16.5 microg/ml. This value was defined as the threshold to detect potential microepistaxis, and corresponded to approximately 245 000 erythrocytes per ml of lavage fluid. Total protein (P < 0.05) and albumin (P < 0.001), but not markers of glandular secretion, were significantly increased in samples with fHb > 16.5 microg/ml compared to those < or = 16.5 microg/ml. Elevations of fHb without changes in albumin were more prevalent in nonallergic rhinitis. CONCLUSIONS: Significant bleeding into nasal lavage samples can contaminate the specimens and increase the concentrations of both fHb and plasma proteins. Increased albumin alone would indicate increased vascular permeability. The mechanism(s) leading to elevated fHb without increased plasma proteins require further investigation.

Adult↗

PubMed2002

A tender sinus does not always mean rhinosinusitis.

BACKGROUND: Sinus tenderness has not been quantitatively assessed. OBJECTIVE: We sought to compare sinus and systemic tenderness in rhinosinusitis, allergic rhinitis, and chronic fatigue syndrome (CFS), and healthy (non-CFS) groups. METHODS: Cutaneous pressures (kg/cm(2)) causing pain at 5 sinus and 18 systemic sites were measured in acute and chronic rhinosinusitis, active allergic rhinitis, healthy non-CFS/no rhinosinusitis, and CFS subjects. RESULTS: Sinus thresholds differed significantly (P </= 10(-11), ANOVA) between non-CFS/no rhinosinusitis (1.59 +/- 0.14 kg/cm(2), mean +/- 95% CI, n = 117), allergic rhinitis (1.19 +/- 0.31, n = 30), exacerbations of chronic rhinosinusitis (1.25 +/- 0.26, n = 25), non-CFS/chronic rhinosinusitis (1.23 +/- 0.27, n = 23), acute rhinosinusitis (1.10 +/- 0.20, n = 22), CFS/no rhinosinusitis (0.98 +/- 0.15, n = 70), and CFS/chronic rhinosinusitis (0.78 +/- 0.12, n = 56). Systemic pressure thresholds were lower for CFS (1.46 +/- 0.15) than for non-CFS (2.67 +/- 0.22, P </= 10(-11)). CONCLUSIONS: The lower sinus thresholds of rhinosinusitis groups validated the sign of sinus tenderness. Sinus and systemic thresholds were both 44% lower in CFS than in non-CFS subjects, suggesting that systemic hyperalgesia contributed to CFS sinus tenderness and "rhinosinusitis" complaints.

Acute Disease↗

PubMed2001

Effects of vehicle movements during transport on the stress responses and meat quality of sheep.

Two groups of 26 lambs were transported for 15 hours either on smooth highways or on rougher secondary roads. Nine of the animals in each group were monitored for heart rate and the plasma levels of cortisol, creatine kinase and lactate dehydrogenase, before the journey began, after four, eight and 12 hours and at slaughter. The pH of the meat was measured 45 minutes and 24 hours postmortem and its colour was assessed 24 hours postmortem. The lambs transported on smooth roads had a lower heart rate and lower plasma cortisol concentrations after eight and 12 hours than the lambs transported on rougher roads. Twenty-four hours after slaughter the pH of the meat of the lambs transported on smooth roads was lower than that of the lambs transported on rougher roads.

Animals↗

PubMed2001

IgE levels are the same in chronic fatigue syndrome (CFS) and control subjects when stratified by allergy skin test results and rhinitis types.

BACKGROUND: Chronic fatigue syndrome (CFS) has an uncertain pathogenesis. Allergies have been suggested as one cause. OBJECTIVE: The aim of this study was to compare serum immunoglobulin (Ig)E in CFS and control subjects to determine whether IgE levels were elevated in CFS. This would be suggestive of increased atopy in CFS. METHODS: IgE was measured by quantitative ELISA (sandwich) immunoassay in 95 CFS and 109 non-CFS control subjects. Subjects were classified by positive or negative allergy skin tests (AST) and rhinitis questionnaires (rhinitis score, RhSc) into four rhinitis types: nonallergic rhinitis (NAR with positive RhSc and negative AST); allergic rhinitis (AR with positive AST and RhSc); atopic/no rhinitis (AST positive/RhSc negative); and nonatopic/no rhinitis (both AST and RhSc negative) subjects. RESULTS: IgE was not significantly different between control (128 +/- 18 IU/mL, mean +/- SEM) and CFS (133 +/- 43 IU/mL) groups, or between control and CFS groups classified into the four rhinitis types. IgE was significantly higher in subjects with positive AST whether or not they had positive RhSc or CFS symptoms. CONCLUSIONS: Elevated IgE and positive AST indicate allergen sensitization, but are not necessarily indicators of symptomatic allergic diseases. There was no association between IgE levels and CFS, indicating that atopy was probably not more prevalent in CFS. Therefore, TH2-lymphocyte and IgE-mast cell mechanisms are unlikely causes of CFS.

Fatigue Syndrome, Chronic↗

PubMed2000

Factors affecting the effectiveness of head-only electrical stunning in sheep.

The effects of factors such as the position of the tongs, the presence of wool, and the wetness of the skin on the efficiency of the head-only stunning procedure, and the duration of the periods of unconsciousness and analgesia were studied in lambs. The degree of insensibility was determined from the evaluation of physiological responses and electroencephalograms. The proportion of successfully stunned animals was significantly higher (P<0.05) in the animals stunned with the tongs in a frontal position than in those stunned with them in a caudal position, in the animals stunned with wet electrodes than in those stunned with dry electrodes and also in the animals without wool than in those with wool. The interval between stunning and sensibility to pain was affected significantly (P<0.01) only by the position of the tongs, being longer in animals with them in a frontal position than in those with them in a caudal position.

Abattoirs↗

PubMed2000

Survey of the effectiveness of stunning procedures used in Spanish pig abattoirs.

Two pig abattoirs (A and B) equipped with an automated head-only and head-to-chest electrical stunning system, and two (C and D) equipped with a manual carbon dioxide stunning system, were evaluated to compare the effectiveness of stunning in a total of 10,454 pigs slaughtered under commercial conditions. In the abattoirs with the electrical stunning system, the percentage of animals that responded to a nose prick was significantly lower (P<0.05) in abattoir B, where a higher current intensity was used (P<0.05), than in abattoir A. No righting reflex was observed in the electrically stunned pigs. In the abattoirs with the carbon dioxide stunning system, the percentage of animals that responded to a nose prick and showed a righting reflex was significantly lower (P<0.05) in abattoir C, where the duration of the carbon dioxide cycle was longer and the interval between discharge from the system to sticking was shorter (P<0.05), than in D. Comparing the electrical and carbon dioxide stunning systems, the pigs stunned with carbon dioxide were significantly more responsive to a nose prick (P<0.05) and 25 per cent of them showed a righting reflex. Under the conditions of the study the fully automated head-only stunning with additional chest electrodes appeared to be more effective and less susceptible to incorrect handling than the manual carbon dioxide stunning system.

Abattoirs↗

PubMed2000

Assessing the degree of association in groups of animals using the concept of entropy.

Nearest-neighbour analysis is commonly used to calculate indices of aggregation in groups of animals. It has several problems, however, including lack of data independence and, when studying groups of animals penned at high densities, the difficulty of determining a given individual's nearest neighbour. We describe an entropy-based method to assess the degree of association (or segregation) of groups of animals. We show that this method gives more information and is more sensitive than the nearest-neighbour technique. An example with a particular experimental situation (mixing groups of lambs) is presented. Copyright 2000 The Association for the Study of Animal Behaviour.

Journal Article↗