Superoxide free radical generation by Amadori compounds: the role of acyclic forms and metal ions

Generation of oxygen free radicals by glycated proteins is widely believed to be one of the causes of oxidative stress in diabetes and aging. Metal ion catalysis is regarded as an essential part of the oxidative mechanism. In this work, we also considered an alternative "metal-free" superoxide radical formation by a number of fructose-amino acids (Amadori compounds) derived from glycine and lysine, which represent the simplest models for early glycated proteins. In the superoxide dismutase-dependent cytochrome c assay, 1 mM Chelex-treated aqueous solutions of monofructose-amino acids 4-6 generated 0.9-3.6 x 10(-10) M s-1 O2*- at pH 7. Surprisingly, the rates of superoxide radical formation in the solutions of difructose-amino acids 7-9 were significantly higher (0.75-5.8 x 10(-9) M s-1 O2*-). The percentage of acyclic sugar anomers (相似文献   

A retrospective investigation into risk factors of sarcoptic mange in dogs

This retrospective study of sarcoptic mange in dogs aimed to identify risk factors for this disease and determine their influence on treatment outcome. Data regarding dog demographics, clinical presentation, diagnostic method, treatment, and outcome were analyzed. No statistical association was found between sex and incidence of sarcoptic mange. However, age of dogs was found to be a risk factor which could increase the chances of dogs contracting sarcoptic mange. The results indicate that the disease predominantly affects young dogs, of all breeds and both sexes, implicating age-related immunity. The most common clinical feature reported was pruritus, with the ear margins preferentially affected. Additionally, contact with other animals played an important role in occurrence of the disease indicating the highly transmissible nature of the disease.     

Change in Neuroplasticity-Related Proteins in Response to Acute Activity-Based Therapy in Persons With Spinal Cord Injury

Background:

Activity-based therapy (ABT) focuses on regaining motor and sensory function below the level of the lesion in persons with a spinal cord injury (SCI). This is accomplished through repetitive training of specific motor tasks. Research has shown that ABT may increase neuroplasticity in the rat and human spinal cord.

Objective:

The primary aim of this study was to examine acute alterations in neuroplasticity-related proteins during ABT in persons with SCI.

Methods:

Volunteers were current participants in an ABT program and consisted of 12 men and 3 women (age, 31.8 ± 10.9 years) with chronic SCI (injury duration, 63.9 ± 54.4 months). A single 2-hour bout of ABT consisted of standing load bearing, body weight-supported treadmill training, whole body vibration, and functional electrical stimulation. Blood samples were obtained at baseline and immediately after completion of each modality to determine serum levels of brain-derived neurotrophic factor (BDNF), prolactin, and cortisol.

Results:

One-way analysis of variance (ANOVA) with repeated measures was used to examine differences in proteins over time. Results revealed baseline levels of BDNF (2.37 ± 1.41 ng/mL) that were lower than previous research has demonstrated in persons with SCI. No change in BDNF or cortisol was found, although prolactin was significantly reduced in response to ABT.

Conclusion:

Despite the length of the bout, acute changes in BDNF were not observed. Whether different intensities or modalities of ABT may promote acute increases in serum BDNF in individuals with SCI remains to be determined and further study is merited.Key words: BDNF, cortisol, exercise, prolactin, rehabilitation, spinal cord injuryRecent research demonstrates that exercise after spinal cord injury (SCI) may increase neuroplasticity in the rat and cycling. Exercise-mediated alterations in BDNF seem to be intensity-dependent, as no change in BDNF was shown during mild exercise versus human spinal cord.^1,2 However, the mechanisms more intense workloads. In addition, prolactin explaining this neuroplasticity are still relatively unexplored. Data from animal studies suggest that neurotrophic factors released during exercise may be a contributing factor. One such protein is brain-derived neurotrophic factor (BDNF), which is found in the brain and periphery. It promotes synaptic plasticity and neuronal growth in noninjured animals and alters motoneuron survival in animals with SCI. Increased levels of BDNF were demonstrated in healthy adults exercising at 55% and 75% maximal workload (Wmax),⁹ as well as in individuals with multiple sclerosis performing 30 minutes of moderate has been identified as a possible mediator of neuroplasticity in the spinal cord as it serves as a marker of serotonergic activation during exercise.¹² In a previous study, prolactin was increased (P < .05) in response to time trial arm ergometry in SCI athletes, yet mild exercise did not induce changes in prolactin. Whether this discrepant response of prolactin to exercise occurs in other individuals with SCI remains to be determined.Exercise also tends to increase cortisol release that may impact neurogenesis via an inhibition of growth in the hippocampus and/or through regulation of BDNF. Nevertheless, it has been suggested that this enhanced stressor response may have little effect upon neuroplasticity; as no correlation has been revealed between BDNF and cortisol, further study is warranted.It is not known whether acute exercise induces significant changes in neurotrophins in men and women with SCI, as only one study has examined this issue. Rojas-Vega et al required previously trained elite male athletes (VO₂max = 34.5 mL/kg/ min) with SCI from T4-T12 to complete a 42-km hand-biking time trial during which blood samples were obtained to measure concentrations of BDNF, cortisol, and prolactin.¹³ Results demonstrated increased (P < .05) BDNF with initiation of exercise, although postexercise values were similar to baseline. Postexercise measures of cortisol and prolactin were also higher (P < .05) than baseline levels. The population that was studied is relatively unique and exercise performed is atypical of common practice in the rehabilitation of persons with SCI, so it remains to be determined whether similar acute increases in neurotrophins would be revealed in less active individuals completing different exercise modalities.Activity-based therapy (ABT) consisting of high-volume training focusing on the core and lower extremities has recently been identified as an effective technique to promote functional recovery in this population.^17–19 The primary aim of this study was to examine acute changes in BDNF, cortisol, and prolactin during a prolonged bout of ABT in men and women with SCI. Individual changes in these proteins were also examined to better understand how different rehabilitation modalities may affect neuroplasticity. These data have the potential to impact the neurorehabilitation of persons with SCI. It was hypothesized that exercise would elicit significant acute changes in BDNF and cortisol as previously demonstrated in this population.¹³     

A portable scanning reflectance spectrophotometer using visible wavelengths for the rapid measurement of skin pigments

A portable rapid scan reflectance spectrometer (400-700 nm in 2.8 s) has been developed for the measurement of cutaneous pigments. The instrument incorporates a tungsten halogen lamp light source, light transmission by fibre optics and wavelength selection by a circular variable wavelength interference filter. A microcomputer controls the instrument and processes the data. The performance of the instrument was evaluated by undertaking in vitro measurements of the reflectance spectra of blood. An index of the haemoglobin content of the sample based on the gradients of the log inverse reflectance spectrum between isobestic points at 527.5, 544 and 573 nm was devised and shown to be independent of the oxygenation of the haemoglobin. The haemoglobin index was combined with measurements at 558.5 nm, a wavelength at which absorbance is sensitive to the oxygenation of haemoglobin, to give a measure of oxygen saturation. The parameter was validated by determining the oxygen dissociation curve of red cells in plasma in vitro at pH 7.33, 37 degrees C and under a partial pressure of 40 mmHg of CO2.     

An epidemiologic study of breast cancer

A case-control study has been conducted in four areas of Canada in which 400 cases of breast cancer matched by age and marital status with neighborhood controls were administered medical and dietary questionnaires. The study is suggestive of an increased risk of breast cancer in post-menopausal women with younger age at menarche and an increased risk with delay of age at natural menopause. No protective effect of early age at first pregnancy was demonstrated in either pre- or post-menopausal women. An increased frequency of pregnancies of four months duration or less was found in cases compared to controls and a greater frequency in pre-menopausal cases compared to controls of a history of irregular menstrual periods. In pre-menopausal women no association has been found between increased height and weight as risk factors for breast cancer. For post-menopausal women, however, a weak association with increased height has been found, while a strong association with increased weight both at the time of menopause and the 12 months preceding diagnosis has ben confirmed.     

Utilization of health services in Western Canada: basic Canadian data from the World Health Organization/International Collaborative Study of Medical Care Utilization.

In a household health survey more than 15 000 individuals in four areas of Canada were interviewed as part of the World Health Organization/International Collaborative Study of Medical Care Utilization. Data were collected to describe the health services system in each area and to measure the population's utilization of health professionals, hospitals, medicines and selected preventive services, perceived acute and chronic morbidity, attitudes and beliefs about health and health care, and sociodemographic characteristics. The proportion of persons with perceived morbidity was twice that of persons reporting visits with a physician in the same 2-week period. Prescribed and nonprescribed medications had been used by more than 50% of respondents in each area in the 2 days before the interview, nonprescribed medicines accounting for more than half of this use. Respondents were found to be more sceptical of medical doctors than of medical science.     

Oral-facial-digital syndrome VII is oral-facial-digital syndrome I: a clarification

We report on further clinical findings in the one single family in the literature classified as oral-facial-digital (OFD) type VII in order to demonstrate that the diagnosis in this kindred should, in fact, be OFD type I. The mother and the daughter described in the original report have since developed polycystic kidney disease. In addition, the daughter recently had a daughter of her own with central nervous system, oral and digital anomalies. Linkage studies have shown that all the affected women share the same haplotype across the previously identified region Xp22.2p22.3 to which OFD I maps. Although the pedigree was too small for a significant lod score, the combination of clinical and molecular information clearly shows that the disease in this family is OFD I. We report this family in order to clarify and simplify the classification of the oral-facial-digital syndrome spectrum and to recommend the removal of OFD VII from the classification system of the oral-facial-digital syndromes.     

THE EFFECT OF AUGMENTED SENSORY FEEDBACK ON THE CONTROL OF SALIVATION

This study assessed the effect of enabling a subject to hear himself salivate while trying to increase or decrease his salivary rate. Two groups of ten subjects were instructed to try to increase their salivary rate when a light to the left was lighted and decrease when a light to the right was lighted. Acetic acid was administered periodically to the right lateral margin of the tongue, and saliva was collected by a parotid capsule and measured by a liquid displacement sialometer. Ten subjects in the feedback group (F) received a 0.2 sec, 1000-cps tone for each drop collected during a trial. Subjects in the no feedback group (NF) received no indication of their salivary rate. Three out of 10 F subjects were able to produce a significantly different (p <. 05) number of drops between increase and decrease periods, and the group as a whole achieved a significant difference between increase and decrease periods. No NF subject, nor the NF group as a whole produced a significant difference.     

Bromocriptine and amantadine in cocaine detoxification

The effects of bromocriptine and amantadine in treating cocaine withdrawal were compared. Withdrawal symptoms are thought to be due to central dopamine depletion. Both bromocriptine and amantadine are dopamine agonists previously reported to diminish withdrawal symptoms. Thirty subjects were withdrawn for 30 days with amantadine, bromocriptine, or placebo. Bromocriptine and amantadine were more effective than placebo for 15 days. Amantadine's effectiveness then declined so that it was no more effective than placebo by experiment's end. Bromocriptine was significantly more effective than both throughout the latter phase of the study. Amantadine's decline in effectiveness is hypothesized to be due to stimulation of dopamine release.