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Knee kinematics and kinetics during gait, step and hop in males with a 16 years old ACL injury compared with matched controls.

The objective of this study was to compare subjects who sustained an ACL injury during soccer 16 years ago with a control group with regard to knee kinematics and kinetics of gait, step activity and cross over hop. Secondly, in the injured subjects, the purpose was to study the impact on kinematics and kinetics of characteristics such as operative status, meniscal resection, being symptomatic, having knee extensor weakness and of having radiographic knee OA. Data from a 3-dimensional gait analysis system (VICON) were used to calculate kinetics and kinematics during gait, step activity and cross over hop of 12 male subjects who had an anterior cruciate ligament injury 16 years earlier. Twelve uninjured subjects matched for age, sex, BMI and activity level served as controls. No significant differences in knee kinematics and kinetics between the ACL group and the control group were found. The variability of some parameters of step and all parameters of hop activity was generally larger in the ACL injured subjects compared with the controls. The ACL injured subjects had a significantly worse clinical status compared with the controls. Reduced knee extension strength was associated with joint moment reductions especially during step activity and cross over hop. Despite a significantly worse clinical status, as determined by self-report and isokinetic strength testing, no significant differences were seen in knee joint kinetics and kinematics in an ACL injured group 16 years after injury compared with a matched control group. The variation was larger among the ACL injured subjects indicating the need for larger study groups in gait and movement analysis in long-term follow-up of ACL injury.

Adult↗

Genetic association studies of schizophrenia using the 8p21-22 genes: prepronociceptin (PNOC), neuronal nicotinic cholinergic receptor alpha polypeptide 2 (CHRNA2) and arylamine N-acetyltransferase 1 (NAT1).

Schizophrenia is a common, genetically heterogeneous disorder with a lifetime prevalence of approximately 1% in the general population. Linkage studies of affected families have now strongly implicated a susceptibility locus on chromosome 8p21-22. Tests of allelic association with markers on 8p21-22 should be able to localise any quantitative trait nucleotides (QTN's) or susceptibility mutations to within a few hundred kilobases. Three brain expressed candidate susceptibility genes, prepronociceptin (PNOC), neuronal cholinergic receptor, nicotinic, alpha polypeptide 2 (CHRNA2) and arylamine N-acetyltransferase 1 (NAT1) have been mapped to chromosome 8p21-22. A case-control, allelic association study was performed using a novel highly polymorphic dinucleotide repeat, D8S2611 near the PNOC gene, two previously characterised dinucleotide repeats, D8S131 and D8S131P at the CHRNA2 locus and an RFLP at the 3'UTR of the arylamine N-acetyltransferase 1 (NAT1) gene. No differences were found in allele frequencies between the patient and control groups. DNA variations or mutations at or near the three genes under study are unlikely to increase susceptibility to schizophrenia in our population sample.

3' Untranslated Regions↗

[Analysis of aromatic DNA adducts in inhabitants of Upper Silesia].

Aromatic DNA adducts levels were measured in white blood cells collected from three groups of volunteers: occupationally exposed group (cokery workers), environmentally exposed group (residents from Silesia), control group (inhabitants of Biała Podlaska) using ELISA and 32P-postlabelling methods. The highest level of DNA adducts was observed in occupationally exposed group, slightly lower in the environmentally exposed group and much lower in the control group. Seasonal variations in the adducts levels were found in total white blood cells and in lymphocytes showing that the levels of DNA adducts reflect the present exposure to genotoxic agents in the air. It was also shown using 32P-postlabelling with HPLC that not only adducts with polycyclic aromatic hydrocarbons were found in human DNA.

Adult↗

[The harmful effects of beta2-sympathomimetic drugs as uterine relaxants on caesarean section (author's transl)].

Beta2-sympathomimetics are the most powerful inhibitors of uterine contraction used in order to prevent threatening fetal asphyxia. These drugs, however, can cause harmful interactions with anaesthetics during caesarean section. Our patient-material consists of parturients, who were given a beta2-sympathomimetic, ritodrine, immediately before caesarean section performed under combined general anaesthesia. These patients showed significantly more marked tachycardia, hypotonia and abundant haemorrhage during operation as a consequence of poor uterine contractility than did the control group. Rapid variations in the circulation of the mother may also be disadvantageous to the wellfare of the fetus. These side-effects can best be minimized by omitting atropine-premedication and by expanding the blood volume of the mother before caesarean section with adequate infusion of Ringer-type.

Adult↗

Determination of 2-phenylethylamine in rat brain after MAO inhibitors, and in human CSF and urine by capillary GC and chemical ionization MS.

A highly specific and sensitive method for the determination of beta-phenylethylamine (PEA) in biological material is presented. It involves prepurification of the extracts on Sep-Pak C18 cartridges, derivatization with heptafluorobutyric acid anhydride, gas chromatography on 50 m capillary columns and quantification by chemical ionization mass spectrometry. Using this method, levels of PEA in the rat brain and the effects of various monoamine oxidase (MAO) inhibitors thereon have been determined. PEA control levels were found to vary considerably: the lowest and highest values found were 0.4 and 12.5 ng/g tissue (n = 25). Within one and the same control group, the variation was somewhat smaller. The preferential or specific inhibitors of MAO A, amiflamine, cimoxatone, CGP 11305 A, moclobemide and toloxatone did not alter rat brain PEA even at high doses. In contrast, the preferential inhibitors of MAO B, deprenil, pargyline and MD 780236, as well as the nonselective agent tranylcypromine, caused strong (up to about 60-fold) increases. The threshold doses corresponded to those which caused about an 80% inhibition of MAO B as measured ex vivo. The method was also used to determine the concentration of PEA in human CSF (mean 17.3 +/- 3.3 ng/ml, range 3-45 ng/ml, n = 15) and urine (males: mean 35 +/- 5 micrograms/g creatinine, range 3.8 - 219 micrograms/g, 78 control days of a total of 12 subjects; females: mean 35 +/- 6 micrograms/g creat., range 2.7 - 266 micrograms/g, 55 control days of a total of 8 subjects).

Adult↗

Platelet activation and platelet-leucocyte interaction in patients with migraine. Subtype differences and influence of triptans.

As migraine is the result of an inflammatory mechanism with serotonergic signalling, leucocyte function, platelet function and intercellular communication between those cells is likely to be connected to the final pathway of the disease. We examined P-selectin expression on platelets (platelet activation) and leucocyte-platelet aggregate formation in 72 migraine patients during their attack-free interval and controls using a flow cytometric assay. Patients suffering from migraine without aura had a significantly increased platelet activation and leucocyte-platelet aggregation compared with the control group, unlike the migraine patients with aura. Patients who had taken a triptan within 3 days prior to the investigation showed platelet activation values similar to the control group. The variations in platelet activation patterns of migraine subgroups could indicate different pathomechanisms. Even outside an attack, migraine patients, particularly those without aura, show an increased level of platelet activation which seems to be down-regulated by triptans. This mechanism may account for the triptan-induced increases in headache frequency. The involvement of proinflammatory platelet-leucocyte cross-talk suggests a possible therapeutic strategy using anti-inflammatory drugs.

Female↗

Maternal Lyme disease and congenital malformations: a cord blood serosurvey in endemic and control areas.

This report describes a cohort study of over 5000 infants and their mothers who participated in a cord blood serosurvey designed to examine the relationship between maternal exposure to Lyme disease and adverse pregnancy outcome. Based on serology and reported clinical history, mothers of infants in an endemic hospital cohort are 5 to 20 times more likely to have been exposed to B. burgdorferi as compared with mothers of infants in a control hospital cohort. The incidence of total congenital malformations was not significantly different in the endemic cohort compared with the control cohort, but the rate of cardiac malformations was significantly higher in the endemic cohort [odds ratio (OR) 2.40; 95% confidence interval (CI) 1.25, 4.59] and the frequencies of certain minor malformations (haemangiomas, polydactyly, and hydrocele), were significantly increased in the control group. Demographic variations could only account for differences in the frequency of polydactyly. Within the endemic cohort, there were no differences in the rate of major or minor malformations or mean birthweight by category of possible maternal exposure to Lyme disease or cord blood serology. The disparity between observations at the population and individual levels requires further investigation. The absence of association at the individual level in the endemic area could be because of the small number of women who were actually exposed either in terms of serology or clinical history. The reason for the findings at the population level is not known but could be because of artifact or population differences.

Adult↗

Detection of syphilitic hearing loss.

Syphilis can cause sensorineural hearing loss that is potentially treatable. To determine the incidence of positive serological findings in patients with sensorineural hearing loss, the rapid plasma reagin card test (RPRCT) and the FTA-ABS test were performed in a study group composed of patients with sensorineural hearing loss of obscure origin. Of the 306 patients with sensorineural hearing loss, 20 (6.5%) demonstrated a positive FTA-ABS as compared with two of 100 (2%) of the control group. Considerable variation was found in the rate of the false-negative and the biological false-positive RPRCT as performed by our hospital and state laboratories when compared with the results of the FTA-ABS test. Syphilis should be considered in any patient with sensorineural hearing loss of obscure origin, despite a negative history for syphilis. The FTA-ABS is the preferred test to exclude hearing loss of syphilitic origin.

Adolescent↗

Prostate-specific antigen: establishment of the reference range for the clinically normal prostate gland and the effect of digital rectal examination, ejaculation, and time on serum concentrations.

This study investigated the serum prostate-specific antigen concentration in 100 healthy men (mean age, 26.3 years; range, 20-29 years) with a clinically normal prostate gland. The effect of digital rectal examination and ejaculation on the serum concentration, and the variability of the serum concentration over 1-week and 1-month periods were examined. In the 100 subjects, the serum prostate-specific antigen concentration ranged from less than 0.1-2.6 ng/ml. The mean, median, and mode were 0.68 ng/ml, 0.6 ng/ml, and 0.4 ng/ml, respectively. The 97.5th percentile value was 2.1 ng/ml. The mean and median changes in the serum concentration after digital rectal examination were -0.013 +/- 0.11 ng/ml and 0.0 ng/ml, respectively (P = 0.59 compared with control group). The mean change after ejaculation was 0.05 +/- 0.12 ng/ml, and the median change was 0.0 ng/ml (P = 0.14 compared with control group). Diurnal variation showed minimal change in 16 patients over a 1-week period. The mean change (p.m. value-a.m. value) was 0.003 ng/ml (range, -0.2-0.06 ng/ml). In addition, the serum concentration showed minimal intrapatient variability in 20 patients throughout a 1-month period; the average coefficient of variation (standard deviation/mean) in these subjects was 16.5% (range, 6.4-45.2%). These results indicate that the range in the serum concentration of prostate-specific antigen for healthy men with a clinically normal prostate gland is significantly lower (0.0-2.6 ng/ml) than the currently employed range (0.0-4.0 ng/ml; Tandem-R PSA assay); in addition, digital rectal examination and ejaculation have no significant effect on the serum concentration. Finally, the time of day has little effect, and the variability in the serum concentration of prostate-specific antigen over a 1-week and 1-month interval is minimal.

Adult↗

Gonadotropin production and release in female goldfish (Carassius auratus) after administration of pimozide and an LHRH analogue as studied by electron microscopy and radioimmunoassay.

The effect of pimozide and an LHRH-analogue (LHRH-A) on gonadotropic cells of the goldfish pituitary gland were described qualitatively and quantitatively. A scale of four categories was devised to reflect various ultrastructural appearances of the cells. Experimental animals were divided into a control group, a group injected with LHRH-A alone, pimozide alone, and groups receiving these two substances in combination. Fish injected with the single substance were killed 12 h after injection while the groups receiving the combined treatments were killed at 4, 12 and 48 h. Serum levels of gonadotropin measured by radioimmunoassay were used to indicate whether an increase in hormone release had occurred. An immunocytochemical technique, the protein A-gold procedure, assured that the cells studied were gonadotropes. The control group showed variation in the profiles of gonadotropic cells. The single treatment groups showed some increase in secretory inclusions. At 4 h after injection the combined treatment caused a significant increase in hormone granules; at 12 and 48 h there was a gradual decrease in content of secretory products, and an increase in vacuolization. The results indicate that the combined pimozide and LHRH-A treatment stimulated gonadotropin production as well as release.

Animals↗

Computerized tomography studies on schizophrenic diseases.

Earlier clinical pneumoencephalographic studies showed a subgroup of schizophrenics that have small and dysplastic cerebral ventricles as well as a subgroup with a "pure defect", i.e., a slight internal brain atrophy. In echoencephalograms of pure and mixed residual schizophrenic syndrome patients, a significantly higher average transverse diameter of the third ventricle was demonstrated compared to that in patients with complete remissions. Correlations cannot be expected between certain groups of disease, e.g., epilepsy, multiple sclerosis, or schizophrenia on the whole, and pneumoencephalographic (PEG) and CT findings. Only schizophrenics with distinct signs of pure defect that had persisted for at least 3 years revealed deviations from normal by CT and PEG, but those with irreversible fixed deformations of personality structure ("Strukturverformungen" [9,10]) did not. In patients who were 50 years of age or less with psychic reactive and psychopathic personality disorders, CT showed an average third ventricle diameter of 4.2 mm (range 2-6 mm). Of 117 schizophrenics (average age 35.5 years), only 28% revealed pathological CT changes. However, of 36 schizophrenics with pure residual syndromes 69% showed pathological CT findings that always concerned the third ventricle, rarely the lateral ventricles, and in no case the cortex. The average transverse diameter of the third ventricle in this subgroup with pure defect was 7.6 mm, as compared to 4.6 mm in the subgroup of schizophrenics with complete remission. There was no increase in size with increasing years until the 50th year in schizophrenics, as well as in the control group of variations of psychic being (neuroses and psychopathic personality disorders).

Adolescent↗

Autoimmune thyroid disease in the puerperium. Predictive value of thyroid enlargement and related hormonal changes occurring during pregnancy.

The incidence of goiter detected during pregnancy and its significance as an indicator of autoimmune thyroid disease after delivery was investigated in a sample of 707 pregnant women (81% in their 2nd trimester of gestation). Goiter was detected in 106 subjects (15%). Blood T4, T3, TSH, free T4 index (FT4I), antimicrosomal antibodies (AMA) and urinary iodine excretion were measured in these women and in a control group of gravidas without goiter. These measurements were repeated at 1 and 3 months after delivery. Compared with controls during pregnancy, subjects with goiter had lower FT4I values (11.0 +/- 2.8 vs 9.0 +/- 1.8; p less than 0.01) and higher TSH values (2.9 +/- 0.6 microU/ml vs 4.2 +/- 2.1 microU/ml; p less than 0.01). In contrast, T4, T3, AMA and urinary iodine excretion values were similar in both groups. In subjects with goiter FT4I values increased over pregnancy levels at 1 month (11.2 +/- 2.0; p less than 0.05) and 3 months (14.0 +/- 3.0; p less than 0.05) after delivery; in 29% a biochemical hyperthyroidism (FT4I greater than 13.5) was detected. During the same period TSH values decreased significantly (1 month: 1.9 +/- 0.7 microU/ml; p less than 0.05; 3 months: 2.7 +/- 3.0 microU/ml; p less than 0.05). Frequency of positive AMA increased from 8.6% during pregnancy up to 32.1% in the post-delivery period (p less than 0.01). In the control group no variation in the FT4I, TSH or AMA were observed after delivery. These results indicate that goiter during pregnancy is common in Chilean gravidas and that it has predictive value for the appearance of autoimmune thyroid disease after delivery.

Adolescent↗

Moderate coffee consumption increases plasma glutathione but not homocysteine in healthy subjects.

BACKGROUND: The consumption of unfiltered coffee, containing bioactive diterpenes, causes an increase in plasma homocysteine concentration. A slight increase in plasma homocysteine is also caused by large quantities of filtered coffee. Coffee terpenes also raise plasma glutathione in mice. AIM: To verify the effect of Italian-style coffee consumption on the plasma concentration of glutathione and homocysteine in healthy subjects. METHODS: Twenty-two volunteers consumed five cups of coffee per day for 1 week and maintained their usual diet. Five subjects were enrolled as controls. The intervention trial was preceded and followed by seven coffee-free days. RESULTS: Plasma glutathione increased by 16% (P < 0.05) on coffee consumption, and returned to the original concentration after the washout period. The increase in plasma homocysteine concentration (13% after 1 week of coffee intake) was not significant. No differences in glutathione or homocysteine concentration were observed in the control group. No variation of plasma hydroperoxide concentration was detectable. CONCLUSIONS: A coffee intake regimen, representing the average consumption of coffee drinkers in Italy, increased the plasma concentration of glutathione, but no significant increase in the plasma homocysteine concentration was detected.

Adult↗

Activity of cardiopulmonary baroreceptors, peripheral resistance and cutaneous microcirculation in patients with peripheral obstructive arterial disease.

OBJECTIVES: To assess the effects of cardiopulmonary baroreceptors on the haemodynamics of the humeral and common carotid arteries in patients suffering from peripheral artery disease (PAD) and to discover whether the stimulation of these receptors modifies the cutaneous microcirculation in the forearm. DESIGN: We studied a group of patients suffering from peripheral artery disease and two groups as controls. SETTING: Patients were examined at the ambulatory for Vascular Research, Division of Vascular Medicine and Rehabilitation, University of Verona. PATIENTS: We studied 15 patients with peripheral artery disease of the lower limbs at Fontaine stage II (group C), 10 free of arterial pathologies (group B) and 10 young people (group A). MAIN OUTCOME MEASURES: We subjected the patients to passive elevation of the legs and the trunk in a horizontal position with pressure monitoring and measurement of the calibre and flow in the brachial and common carotid arteries using a colourDoppler ultrasound. We also studied the cutaneous microcirculation with laserDoppler flowmetry. RESULTS: During the test, arterial pressure and cardiac frequency remained constant in group A, systolic pressure values showed a slight, but statistically significant increase in group B, whilst the increase in systolic pressure values at this stage was marked in group C. Diastolic pressure values and cardiac frequency remained unchanged in all groups. The calibre of the humeral artery increased in the control groups. Carotid resistance was unchanged in the three groups. Humeral resistance during the test decreased in the two control groups whilst it increased in group C. The number of perfusion units felt in the control groups; no variations in group C. CONCLUSIONS: Our study demonstrates, in patients with peripheral artery disease, a reduction in the activity of the cardiopulmonary baroreceptors with an increase in the humeral resistance during the test and impairment of the mechanisms of cutaneous microcirculatory vasoregulation in the forearm.

Aged↗

Educating for empathy. A review.

OBJECTIVE: Empathy in the medical setting is appreciation of the patient's emotions and expression of that awareness to the patient. Named as an essential learning objective by the American Association of Medical Colleges, empathy is believed to significantly influence patient satisfaction, adherence to medical recommendations, clinical outcomes, and professional satisfaction. The objective of this study was to identify effective strategies to enhance empathy in undergraduate medical students. DATA SOURCES: We searched PubMed for studies that address the effectiveness of strategies for teaching empathy to medical students. We identified 13 peer-reviewed, English language, qualitative and quantitative studies reporting primary data on interventions that aim to foster empathy in undergraduate medical students, using Medical Subject Heading terms education, medical, undergraduate or student, medical crossed with empathy. RESULTS: These studies indicate that empathy may be amenable to positive change with a range of interventional strategies. Communication skill workshops addressing the behavioral dimension of empathy show greatest quantitative impact on participants. However, current studies are challenged by varying definitions of empathy, small sample sizes, lack of adequate control groups, and variation among existing empathy measurement instruments. CONCLUSION: Given the methodological limitations of the available studies, and uncertainty about which dimensions of empathy should be addressed, larger studies using validated measurement tools are recommended.

Communication↗

Ovarian hormones, anticonvulsant drugs, and seizures during the menstrual cycle in women with epilepsy.

The excretion of three oestrogen fractions and progesterone metabolites in 64 female epileptic patients was determined during the menstrual cycle, and in 50 women of this sample serum phenytoin and phenobarbitone levels were measured. A significant decrease of both hormones in epileptic patients was found as compared to a control group. The variations in serum phenytoin levels were greater in females with so-called catamenial epilepsy with a marked fall of drug levels between days 27 and 28 corresponding with an increase of seizure frequency. The effect of progesterone deficit on seizure susceptibility before menstrual bleeding is discussed, and the need of serum anticonvulsant level determination during the premenstrual phase in epileptic women is suggested.

Adolescent↗

Elevated cholecystokinin-like activity in the duodenal mucosa in patients with cholecystolithiasis.

Cholecystokinin (CCK)-like activities in the duodenal mucosa of the patients with cholecystolithiasis were determined with the bioassay method we established. The results obtained are as follows: The gall bladder of the patients with cholecystolithiasis following oral administration of egg yolk has contraction rates comparable to those of the normal subjects in the control group, whereas the contraction rate of the gall bladder of the patients with cholecystolithiasis following administration of caerulein was markedly lower than that of the normal subjects in the control group. The variations in the contraction of the gall bladder in time lapse following administration of caerulein to the patients with cholecystolithiasis strongly denied the possibility of either insufficient release of CCK or accelerated dissimilation of CCK in those patients. Based on the above findings, it was concluded that the sensitivity of the gall bladder to CCK decreases in the patients with cholecystolithiasis and that, in order to replenish it, the feed-back mechanism reacts to sufficiently promote the production of CCK in the duodenal mucosa. The similar mechanism was noted in the variations of the findings of normal subjects as age advanced.

Adult↗

Large amount of vitamin A has no major effects on thyroidal hormone synthesis in two-stage rat thyroid carcinogenesis model using N-bis(2-hydroxypropyl)nitrosamine and thiourea.

In our previous investigation, which focused on two-stage carcinogenicity in the thyroid, rats were administered N-bis(2-hydroxypropyl)nitrosamine (DHPN), followed by thiourea (TU) over an experimental period of 19 weeks. Simultaneous treatment with a high level of vitamin A (VA) enhanced the induction of proliferative lesions that originated from the thyroidal follicular epithelium. To examine whether hormone synthesis in the thyroid could be inhibited by simultaneous treatment with a large amount of VA and TU, all of the rats were initially given a single subcutaneous injection of 2,800 mg DHPN/kg followed by a supply of 0% TU + 0% VA (DHPN only, control group), 0.2% TU in their drinking water (DHPN/TU group), 0.1% VA in their diet (DHPN/VA group), or 0.2% TU + 0.1% VA (DHPN/TU + VA group) during an experimental period of 4 weeks. Results obtained indicate that the iodine uptake and organification, namely iodination of tyrosine residue in thyroglobulin, of the thyroid, were significantly decreased in the DHPN/TU group compared to the DHPN control group. The variation in these values was attributable to the inhibitory effect of TU upon thyroid hormone synthesis. Results obtained from the DHPN/TU + VA and DHPN/TU groups were comparable. Therefore, the possibility that modification of hormone synthesis contributes to the enhancing effect of simultaneous treatment with a large amount of VA on thyroidal tumor induction by TU is considered to be very minimal.

Adenoma↗