Bacteriology of the lower respiratory tract as determined by fiber-optic bronchoscopy and transtracheal aspiration

For assessment of the validity of cultures of tracheobronchial secretions and exudates (TBSE) obtained by fiber-optic bronchoscopy, the aerobic and anaerobic flora of expectorated saliva and TBSE obtained by fiber-optic bronchoscopy from nine healthy volunteers and eight patients were compared with those obtained by fiber-optic bronchoscopy as well). Normal volunteers yielded both aerobic and anaerobic bacteria in amounts usually less than 104.5 colony-forming units (cfu)/ml in TBSE obtained by fiberoptic bronchoscopy. In patients with chronic bronchitis, 42 isolates of aerobic bacteria (104-105.5 cfu/ml) and only 10 isolates of anaerobes (usually less than 104 cfu/ml) were reovered from 15 samples obtained by trantracheal aspiration. The data lead to the conclusion that low-level contamination (less than or equal to 104 cfu/ml) with oral flora is common in TBSE obtained by fiber-optic bronchoscopy. A single potential pathogen in numbers of greater than or equal to 105 cfu/ml may be of etiologic significance, particularly if recovered from purulent drainage material from a localized portion of the lung. Under circumstances in which quantitative bacteriology cannot be done, TBSE obtained by transtracheal aspiration will most reliably reflect the bacterial flora present in the lung.     

Force plate studies of equine biomechanics

The force plate can measure a wide range of effects in the horse. The same instrument can record forces from more than a ton in the galloping animal to 25 g associated with the action of the heart. In all probability, the force plate will develop into a valuable clinical instrument.     

The postconcussional syndrome reappraised

Despite the apparently benign nature of mild head injury, reflected by the short post-traumatic amnesia duration, relative absence of CNS signs and brief hospital stay, a significant number of patients report persistent symptomatology over the weeks or months afterwards. Largely subjective in nature, such symptom clusters are termed the postconcussion syndrome. The discrepancy between the predominantly subjective complaints and negative examination findings has generated uncertainty and debate about the respective causation roles of organic and psychogenic factors. Over the past 30 years evidence for organic brain changes has accumulated through studies of cerebral circulation, neuropsychological deficits, evoked potential recordings and neuroimaging. This paper reviews data from two UK prospective studies of the evolution and course of postconcussional symptomatology using parallel psychosocial, neuropsychiatric, quantitative EEG and brainstem auditory evoked potential recordings. Changes in theta power occurred early with resolution within 10 days. Prolonged brainstem evoked response I-V intervals were seen in between 27% and 46% of patients. Symptom chronicity noted in a minority of people (13%) was associated with a high prevalence of brainstem dysfunction, while the degree of QEEG recovery appeared to relate to the intensity of early symptom reaction to the trauma. Levels of perceived stress at the time of the injury or afterwards were not related to symptom formation, but chronic social difficulties were a feature of the 21% of patients who initially improved but had a late exacerbation of symptoms between 6 weeks and 6 months after the trauma.     

Association between insulin and blood pressure in relation to the influence of body mass index

The relationship between plasma insulin level and systolic blood pressure (SBP) was investigated by multiple linear regression procedure in 410 Chinese non-diabetics. The significant positive correlation between SBP and 2-hour plasma insulin (INS 2h) after 75g glucose load was found in the BMI (body mass index) 15.9-27.0 group (n = 287) after the adjustment for age, sex, BMI, smoking and plasma cholesterol (P = 0.01). However, this significant correlation was gradually diminished with the expansion of the BMI range, ie. P = 0.04 in the BMI 15.9-29.0 (n = 356) group, P = 0.07 in the BMI 15.9-31 (n = 389) group, and P = 0.12 in the BMI 15.9-33 (n = 402) group after the same adjustment of variables. Interestingly, the significant inverse correlation between insulin-BMI interaction term (product of BMI and insulin) and SBP was found (P = 0.04) in the presence of the significant positive correlation between 2-hour plasma insulin and SBP (P = 0.02) after adjustment of the above mentioned five factors in the whole group (BMI 15.9-42.2, n = 410). These results indicated that SBP is independently correlated with plasma insulin level in the studied population, and that the severer obesity may interfere the net effects of insulin on the elevating of blood pressure.     

Short communication: Survey of hepatic copper concentrations in Midwest dairy cows

Previous research from our laboratory and others indicates that liver copper concentrations in dairy cattle are commonly well above those recognized as adequate for the nutritional needs of the animal. It has also been speculated that hepatic copper concentrations have been increasing in recent years. Unlike other species, the threshold at which elevated liver copper concentrations becomes deleterious to hepatocytes is not known for cattle. Therefore, the objectives of this study were 3-fold: (1) to delineate differences in the range and mean dry matter hepatic copper concentration for dairy cattle in a retrospective analysis (January 1, 2007, to December 31, 2015), (2) to investigate hepatic copper concentrations in Midwest cull dairy cattle, and (3) to evaluate histologic changes in hepatocellular morphology in the context of copper concentration in cull cows. Furthermore, microscopic changes in hepatocellular morphology or architecture were examined and scored for evidence of inflammation, fibrosis, necrosis, and abundance of rhodanine-stained granules using hematoxylin and eosin and rhodanine staining. The retrospective analysis found copper concentrations within a range of 3 to 1,963 µg/g, with a mean of 473 µg/g. Hepatic copper concentrations in our retrospective study did not increase with time. In our abattoir analysis, copper concentrations ranged from 15 to 978 μg/g, with a mean of 390 μg/g. This study found that the range and mean hepatic copper concentrations were comparatively less in the current abattoir study than copper concentrations in our retrospective analysis. There was no evidence for hepatocellular changes associated with increased copper burdens in this study population.