The relation of the accumulation of cadmium in human placenta to the intake of high-fibre grains and maternal iron status.

Exposure to cadmium via the diet is known to depend to a large extent on the intake of cereal grains, particularly the high-fibre fractions of wheat. Subjects with low iron status absorb more cadmium than those with better iron status. The purpose of the present study was to determine to what extent cadmium accumulation in human placenta is affected by the intake of grain fibre and maternal iron status during pregnancy. Thirty-nine pregnant women participated in the study. In each trimester the women were requested to complete a dietary history and to allow blood samples to be taken for haemoglobin, serum ferritin and serum thiocyanate determinations, the latter as a marker for smoking. At delivery the whole placenta was taken for the determination of the cadmium concentration. The 32 women who had serum thiocyanate levels less than 70 mumol/l, who had completed at least one dietary history and from whom a blood sample was obtained in the third trimester, were included in the final statistical analyses. In the group of women who consumed less than the median intake of grain fibre and had more than 15 micrograms ferritin/l serum in the third trimester, the placenta cadmium concentration was nearly half that in the placentae of women who had consumed more grain fibre or had lower iron status in late pregnancy.     

A multivariate study of protective effects of Zn and Cu against nephrotoxicity induced by cadmium metallothionein in rats.

Factorial experimental design was used to study the protective effects of Zn and Cu on cadmium-metallothionein(CdMT)-induced nephrotoxicity in male Wistar rats. In the factorial design two levels of Zn (0 and 25 mg/kg body weight), two levels of Cu (0 and 12.5 mg/kg), and two levels of CdMT (0.1 and 0.4 mg of Cd/kg) were used as varied factors. The factorial design was complemented with a center point with all three variables at an intermediate setting, i.e., Zn at 12.5 mg/kg, Cu at 6.25 mg/kg, and CdMT at 0.25 mg Cd/kg. Each of the nine combinations of settings was administered to one of nine groups with six rats in each. Zn and Cu were injected sc 24 hr prior to the injection of CdMT. The concentrations of protein and Ca in urine and Ca in renal cortex were used as effects. The relationship between the experimental design settings and the effects were modeled with multiple regression. The multiple regression analysis revealed that for the high dose of CdMT (i) the enhanced values of protein in urine caused by CdMT injection could be more efficiently reduced by Zn than by Cu, and (ii) excessive Ca in urine and renal cortex could be more efficiently reduced by Cu than by Zn. No significant synergism or antagonism between Cu and Zn was found. These models can be used to estimate the dose levels of Zn and Cu which will reduce the toxic effects of CdMT. The treatment of 20.4 mg/kg Zn, for example, will reduce the effects of 0.4 mg Cd/kg as CdMT on protein in urine, and 2.8 mg/kg Cu will reduce the Ca in urine to the levels of those caused by 0.25 mg Cd/kg (no Zn and Cu). Similarly, the effect of 0.4 mg Cd/kg on Ca level in renal cortex can be reduced to that of 0.28 mg Cd/kg as CdMT by 7.98 mg Cu/kg, which is three times as efficient as Zn. The obtained results might be of importance in understanding the mechanism of cadmium toxicity and the potential risk to the health of the population exposed to cadmium occupationally or environmentally.     

Early pathological changes in progressive multifocal leukoencephalopathy: a report of two asymptomatic cases occurring prior to the AIDS epidemic

Serial sections of formalin-fixed, paraffinembedded blocks from two asymptomatic, non-AIDS cases of progressive multifocal leukoencephalopathy (PML) were stained with a double-label immunocytochemical method for detection of glial fibrillary acidic protein and JC virus (JCV) capsid proteins and with luxol fast blue/hematoxylin-eosin. In case 1 small, rounded lesions of about 1-mm diameter were seen within a restricted area in the posterior part of the superior frontal gyrus of both cerebral hemispheres, suggesting an early manifestation of the disease. Fully developed demyelinated lesions of the classical type with JCV-infected oligodendrocytes appeared in the white matter and along its border with the cortex. Lesswell-developed lesions, believed to be precursors to the fully developed ones, were seen in the gray and white matter. Of special interest were areas which contained small collections of enlarged, glial fibrillary acidic protein (GFAP)-positive astrocytes without capsid antigen and which seemed to lack destruction of myelin as judged from the appearance of matching serial sections stained for myelin. Large lesions in the brain of case 2 showed the well-known features of advanced PML. The close relation between some astrocytes and oligodendrocytes with viral antigen raises the possibility of early intercellular passage of virus. Vacuolation, seen within or near lesions in both cases, has previously been noted in the CNS infected by HIV, but not in PML. It is suggested that PML, a disease of both oligodendrocytes and astrocytes, may actually begin in astroglial cells which, under the influence of a restricted JCV infection, become reactive, express GFAP and pass on virus to the more highly susceptible oligodendrocytes with which they are in contact.Supported in part by a grant N.S.07596 from the National Institute of Neurological Disorders and Stroke. The work was carried out in the Laboratory of Experimental Neurophathology, NINDS, and in the Department of Pathology II, Karolinska Institute, Stockholm     

Anterior stabilization of pathologic dens fractures

By an anterior approach, six pathologic dens fractures were stabilized with screws and methyl methacrylate cement. All the patients had immediate pain relief and could be mobilized without external support. Using the anterior approach, the tumor can be removed and the instability neutralized at the site of the lesion.     

Androgen treatment of abdominally obese men

Middle-aged men with abdominal obesity were treated in a double-blind study with moderate doses of transdermal preparations of testosterone (T), dihydrotestosterone (DHT), or placebo. This resulted in moderately elevated T concentrations and marked decreases in follicle stimulating and luteinizing hormones in the group treated with T, while the DHT group showed elevated DHT, markedly lower T values, and less diminution of gonadotropin concentrations. In the group treated with T visceral fat mass decreased (measured by computerized tomography) without significant changes in other depot fat regions. Lean body mass did not change. In the group treated with T, glucose disposal rate, measured with the euglycemic hyperinsulinemic clamp method, was markedly augmented. Plasma triglycerides, cholesterol, and fasting blood glucose concentrations as well as diastolic blood pressure decreased. There were no such changes in the DHT or placebo treatment groups. The men treated with T reported increased well-being and energy. In none of the groups did prostate volume, specific prostate antigen concentration, genito-urinary history, or urinary flow measurement change. It is suggested that supplementation of abdominal obese men with moderate doses of T might have several beneficial effects.     

Accommodative facility training with a long term follow up in a sample of school aged children showing accommodative dysfunction

The primary aim of this project was to study the effect of flip lens-training on the accommodative function in a group of children with accommodative dysfunction and subjective symptoms such as asthenopia, headache, blurred vision, and avoidance of near activity. We also wanted to measure the accommodative facility among the children in comparison with a control group. Another aim of the study was whether flip lens-training increased accommodative facility, and to find out if it also had a positive effect on their asthenopia and related problems also in long term. Following the training period the accommodative facility and accommodative function significantly increased and two years after finishing the training period no child had regained any subjective symptoms and the objective findings were almost the same as at the end of facility training period. These results suggest that accommodative facility training is an efficient method built on loss of symptoms among children with accommodative infacility. This revised version was published online in July 2006 with corrections to the Cover Date.     

Validity of a questionnaire survey: response patterns in different subgroups and the effect of social desirability

Questionnaire surveys are often used in epidemiology and survey research. However, investigations have shown that the method suffers from biases. If the intention is to examine differences between subgroups in a sample, studies have shown that people tend to give answers to questionnaires more according to a social norm than to the actual situation. This has been called social desirability. The aim of this study was to investigate response bias in subgroups of a sample in a large questionnaire survey (n = 9,200) and to study whether social desirability has an impact on survey results in dental research. The answers were divided into subgroups according to gender, age, and residence and were compared with corresponding data from dental insurance claims. The levels of agreement were found to vary considerably and the differences were highly statistically significant. The variation in agreement showed that bias on the group level increased when the distance from an anticipated social norm was larger. This implies that the divergence from a socially desirable mode of action influences the magnitude of the bias.