Intraoperative changes in coronary resistance during aortic valve replacement

Coronary vascular resistance was investigated in 10 patients undergoing aortic valve replacement using continuous constant-pressure coronary perfusion at 32 degrees C. After coronary flow was initiated, resistance was low but increased steadily until it reached a certain resting level. The plateau was attained faster after a short period of anoxia than after a longer period. The initial postischemic resistance was dependent on the duration preceding anoxia, being of the same magnitude after short and moderate periods of anoxia but significantly higher after a long period. This resistance difference between the groups lasted for the whole perfusion. The total coronary resistance and flow reached a plateau in 30 minutes, while resistance increased threefold but flow decreased to half of the initial postanoxia flow. Our results indicate the importance of initiating coronary perfusion soon after aortic cross-clamping to avoid increase in the initial vascular resistance and subsequent inadequate myocardial flow.     

Effect of mecamylamine on the fate of dopamine in striatal and mesolimbic areas of rat brain; interaction with morphine and haloperidol.

1 The effects of the nicotinic cholinoceptor blocking drug, mecamylamine (alone or in combination with morphine or haloperidol) were investigated on the striatal homovanillic acid (HVA) concentration and on the alpha-methyl-p-tyrosine (AMPT)-induced depletion of striatal or mesolimbic dopamine content in the brain of rats. 2 Mecamylamine (2 mg/kg) alone did not alter the striatal HVA concentration, but it reduced the probenecid-induced accumulation of HVA. Mecamylamine pretreatment reduced the morphine- and haloperidol-induced elevation of striatal HVA concentrations. Hexamethonium did not alter the striatal HVA concentration when given alone or in probenecid- or morphine-treated rats, whereas pempidine (8 mg/kg) clearly reduced the probenecid-induced accumulation of HVA in the striatum. 3 Mecamylamine (2 and 8 mg/kg) slowed the rate of AMPT-induced depletion of dopamine from the striatum and mesolimbic area both in the brain of control rats treated with morphine or haloperidol. 4 Mecamylamine slightly prolonged the cataleptic effect of morphine. 5 The results indicate that mecamylamine inhibits the release of dopamine both from the striatal and mesolimbic dopaminergic neurones.     

Prefrontal TMS produces smaller EEG responses than motor-cortex TMS: implications for rTMS treatment in depression

Rationale The stimulus intensity of prefrontal repetitive transcranial magnetic stimulation (rTMS) during depression treatment is usually determined by adjusting it with respect to the motor threshold (MT). There is some evidence that reactivity of the prefrontal cortex to transcranial magnetic stimulation (TMS) is lower than that of the motor cortex at MT stimulation. However, it is unknown whether this is true when other stimulus intensities are used. We investigated whether the magnitude and shape of the overall TMS-evoked electroencephalographic (EEG) responses differ between prefrontal and motor cortices. Methods Magnetic pulses to the left motor and prefrontal cortices (the middle frontal gyrus identified from magnetic resonance images) were delivered at four intensities (60, 80, 100, and 120% of MT of the right abductor digiti minimi muscle) for six subjects. Simultaneously, EEG was recorded with 60 scalp electrodes. Results Global mean-field amplitudes (GMFAs) reflecting overall cortical activity were significantly smaller after prefrontal- than after motor-cortex TMS. A significant positive correlation (r _s=0.84, p<0.01) was found between GMFAs of motor- and prefrontal-cortex TMS across the experiments. However, when correlation between the responses of motor and prefrontal cortices was examined, significant positive correlations were found at 80 and 100% intensities only. Conclusions This study provides further evidence that the prefrontal and motor cortices have different reactivity to TMS, but the MT may be used for determining the stimulus intensity of prefrontal rTMS treatment in depression, at least at motor threshold intensities or near to it.     

Rising incidence of fall-induced injuries among elderly adults

Aim and methods Fall-induced injuries in older people are a major public health concern in modern societies with aging populations. Despite this, very little is known about the population trends in these injuries and long-term follow-ups are lacking. Our aim was to determine the current trends in the number and incidence (per 100,000 persons) of fall-induced injuries in older adults in Finland, an EU country with a well-defined white population of 5.2 million, taking into account all persons 80 years of age or older who were admitted to our hospitals for primary treatment of a first fall injury over the period 1970–2002.Results The number of fall-induced injuries in elderly Finns increased considerably between the years 1970 and 2002: from 1,139 to 11,835 overall (a 10.4-fold rise), and from 927 to 9346 in women (a 10.1-fold rise) and from 212 to 2489 in men (an 11.7-fold rise). In both genders, the age-adjusted incidence of fall-induced injuries also increased during the study period, the incidence being 2711 (women) and 1441 (men) in 1970, and 6681 (women) and 4726 (men) in 2002. Assuming that the observed relatively linear development in the incidence rates of fall-induced injuries in elderly Finnish people continues and that the size of this population increases as predicted, the annual number of Finns aged 80 years or older experiencing a fall-induced injury can be estimated to increase further steeply during the coming three decades, from the above-noted 11,835 to about 42,500 in the year 2030 (a 3.6-fold rise).Conclusion The number of fall-induced injuries among elderly Finns shows an alarming rise with a rate that cannot be explained merely by demographic changes. Wide-scale preventive measures should be urgently adopted to control the rising burden of these injuries.     

Soluble glycoprotein V as a quality marker of platelet concentrates stressed by transportation

BACKGROUND: Despite ongoing improvements in storage conditions for platelet concentrates (PCs) for clinical use, leukoreduced platelets (PLTs) undergo subtle changes that are partly due to PLT activation. As PLTs are activated, the expression of P-selectin (CD62P) increases, and soluble glycoprotein V (sGPV) is released. GPV, part of the GPIbIXV complex, has been suggested as a marker of PLT activation. STUDY DESIGN AND METHODS: An array of assays, used for quality control of PCs, was performed and the results were compared. The tests included PLT count, swirling, mean PLT volume, extent of shape change (ESC), hypotonic shock response (HSR), CD62P, lysosomal membrane protein (CD63), sGPV, and the metabolic tests (pH, pO(2), pCO(2), lactate, glucose). The performance of the assays was evaluated during the storage period by comparing buffy coat-derived PCs (24 PCs of 4 units) stored on flatbed agitator or stressed twice by overnight transportation. RESULTS: The repeatability of all tests was good. ESC and HSR correlated with each other (r = 0.559). Importantly, there were also associations between sGPV and ESC (r = -0.564) and HSR (r = -0.389). The correlations of sGPV with lactate and glucose concentrations and with expression of CD62P and CD63 were also good. No significant changes were induced by two overnight transportations. CONCLUSION: sGPV might be applicable for statistical process control of the quality of PCs, in addition to metabolic tests. It may also be helpful in analyzing potential improvements in blood component processing. Repeat transportation of PCs may cause minimal changes on PLT in vitro properties, if any.     

Recurrent tinnitus and associated ear symptoms in adults

This study aimed to reveal in general population the prevalence, associations, and statistical model of recurrent tinnitus by means of a mailed questionnaire. The study sample consisted of 1720 randomly selected adults who were classified into three subgroups: recurrent (once a month or more often), occasional (less often than once a month), and no tinnitus. According to age and gender standardized prevalence, recurrent tinnitus was reported in 15% of the sample. It was statistically highly significantly associated with earache, fullness of ears shoulder pain, the 25-years age group, and visits to a physician. The strongest predictor of recurrent tinnitus was fullness of ears followed by earache, shoulder ache, and temporomandibular disorder pain. We conclude that recurrent tinnitus seems to be quite common in adults and associated with earache and fullness of ears In patients with tinnitus without clinical findings, the examination of the stomatognathic system and cervical spine is recommended.     

Effect of probiotics and breastfeeding on the bifidobacterium and lactobacillus/enterococcus microbiota and humoral immune responses

OBJECTIVE: To assess impact of probiotics and breastfeeding on gut microecology. STUDY DESIGN: Mothers were randomized to receive placebo or Lactobacillus rhamnosus GG before delivery, with treatment of the infants after delivery. We assessed gut microbiota, humoral immune responses, and measured soluble cluster of differentiation 14 (sCD14) in colostrum in 96 infants. RESULTS: Fecal Bifidobacterium and Lactobacillus/Enterococcus counts were higher in breastfed than formula-fed infants at 6 months; P <.0001 and P=.01, respectively. At 3 months, total number of immunoglobulin (Ig)G-secreting cells in breastfed infants supplemented with probiotics exceeded those in breastfed infants receiving placebo; P=.05, and their number correlated with concentration of sCD14 in colostrum. Total numbers of IgM-, IgA-, and IgG-secreting cells at 12 months were higher in infants breastfed exclusively for at least for 3 months and supplemented with probiotics as compared with breastfed infants receiving placebo; P=.005, P=.03 and P=.04, respectively. Again, sCD14 in colostrum correlated with numbers of IgM and IgA cells; P=.05 in both. CONCLUSIONS: We found an interaction between probiotics and breastfeeding on number of Ig-secreting cells, suggesting that probiotics during breastfeeding may positively influence gut immunity.     

Carotid plaque mast cells associate with atherogenic serum lipids, high grade carotid stenosis and symptomatic carotid artery disease. Results from the helsinki carotid endarterectomy study

OBJECTIVE: Increased numbers of mast cells (MCs) are present in ruptured coronary plaques, suggesting to play a role in acute coronary syndromes. We evaluated the distribution densities of MCs, macrophages and T cells in carotid plaques and correlated these findings to stroke risk factors as well as history of stroke or TIA. METHODS AND RESULTS: Seventy-eight carotid samples from 75 patients (16 plaques from asymptomatic patients and 62 from patients with recent ischemic symptoms) undergoing carotid endarterectomy with an internal carotid stenosis >70% that were immunostained and quantified for MCs, macrophages and T cells. The MC distribution density showed positive correlation with the degree of carotid stenosis (p = 0.012), serum levels of total cholesterol (p = 0.021), LDL cholesterol (p = 0.013) and triglycerides (p = 0.005), and an inverse correlation with serum HDL cholesterol levels (p = 0.001). The average MC density (p = 0.023), but not the macrophage (p = 0.58) or T cell (p = 0.74) density, was higher in the symptomatic than in the asymptomatic patients. In a comparison of plaques ipsilateral and contralateral to the thromboembolic event, the densities of the three types of inflammatory cells were similar. CONCLUSIONS: Increased MC distribution density is associated with an atherogenic serum lipid profile, high-grade carotid artery stenosis and symptomatic carotid artery disease. These findings suggest a potential involvement of MCs in the pathophysiology of carotid artery stenosis.     

Do individuals with former amphetamine dependence have cognitive deficits?

The association between former amphetamine dependence and cognitive performance was studied in a sample of 12 individuals with former amphetamine dependence who had been abstinent for at least 1 year and in 12 age-, gender- and verbal IQ-matched controls. The groups were compared by cognitive tests on attention, memory, executive function and fluid intelligence. Individuals with former amphetamine dependence performed significantly poorer than controls in memory domain. Follow-up analysis of variance showed minor deficits in tests of delayed verbal memory. The results remained essentially the same when participants with current DSM-IV axis I diagnosis were excluded from the analysis. It is concluded that individuals with former amphetamine dependence have normal cognitive function with the possible exception of verbal memory. Thus, if widespread cognitive deficits are found in individuals with former amphetamine dependence, etiologies other than amphetamine abuse as such should be carefully investigated.