Distinct patterns of brain activity evoked by histamine-induced itch reveal an association with itch intensity and disease severity in atopic dermatitis.

BACKGROUND: Little is known about brain mechanisms supporting the experience of chronic puritus in disease states. OBJECTIVES: To examine the difference in brain processing of histamine-induced itch in patients with active atopic dermatitis (AD) vs. healthy controls with the emerging technique of functional magnetic resonance imaging (fMRI) using arterial spin labelling (ASL). METHODS: Itch was induced with histamine iontophoresis in eight patients with AD and seven healthy subjects. RESULTS: We found significant differences in brain processing of histamine-induced itch between patients with AD and healthy subjects. Patients with AD exhibited bilateral activation of the anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), retrosplenial cingulate cortex and dorsolateral prefrontal cortex (DLPFC) as well as contralateral activation of the caudate nucleus and putamen. In contrast, healthy subjects activated the primary motor cortex, primary somatosensory cortex and superior parietal lobe. The PCC and precuneus exhibited significantly greater activity in patients vs. healthy subjects. A significant correlation between percentage changes of brain activation was noted in the activation of the ACC and contralateral insula and histamine-induced itch intensity as well as disease severity in patients with AD. In addition, an association was noted between DLPFC activity and disease severity. CONCLUSIONS: Our results demonstrate that ASL fMRI is a promising technique to assess brain activity in chronic itch. Brain activity of acute itch in AD seems to differ from that in healthy subjects. Moreover, the activity in cortical areas involved in affect and emotion correlated to measures of disease severity.

Repetitive scratching and noxious heat do not inhibit histamine-induced itch in atopic dermatitis.

BACKGROUND: Repetitive scratching is the most common behavioural response to itch in atopic dermatitis (AD). Patients with chronic itch often report that very hot showers inhibit itch. We recently reported that scratching and noxious heat stimuli inhibit histamine-induced itch in healthy subjects. However, no psychophysical studies have been performed in AD to assess the effects of repetitive heat pain stimuli and scratching on histamine-induced itch. OBJECTIVES: To examine the effects of repetitive noxious heat and scratching on itch intensity in patients with AD using quantitative sensory testing devices. METHODS: Itch was induced with histamine iontophoresis in 16 patients with AD in both lesional and nonlesional skin as well as in 10 healthy subjects. Repetitive noxious heat and scratching were applied 3 cm distal to the area of histamine iontophoresis. Subjects rated their perceived intensity of histamine-induced itch with a computerized visual analogue scale. RESULTS: Our results demonstrate that repetitive noxious heat and scratching do not inhibit itch intensity in lesional and nonlesional AD skin but do so in healthy skin. Of note, both these stimuli increase itch intensity in lesional AD skin. CONCLUSIONS: Our results strongly suggest that scratching and noxious thermal stimuli have a different effect upon histamine-induced itch perception in patients with AD when compared with healthy controls. This difference may be associated with both peripheral and central sensitization of nerve fibres in AD.

A correlation of secondary aerosol (nitrate and sulfate) with respirable particulate matter (RPM) in ambient air at different traffic junctions of Vadodara city.

The correlation study of secondary aerosol (nitrate and sulfate) with RPM in ambient air at different traffic junctions of Vadodara city is reported. RPM was analyzed using Ion Chromatography technique and measured the level of nitrate and sulfate in ambient air. The correlation studies of these particulates with RPM have been established. The average concentration of sulfate and nitrate in ambient air was found 35.74 microg/m3 and 24.22 microg/m3, which ranged of 5.33-84.69 and 1.93-77.86 microg/m3 respectively. The correlation of RPM and SO4 (r = 0.813, P<0.01), RPM-NO3 (r = 0.5549, P<0.01) and SO4-NO3 (r = 0.6133, P<0.01) were found significant. The presence of sulfate and nitrate in RPM is 8.25% and 5.60% . The pH of water extract of RPM averaged 6.81, which ranged 6.17-7.28. Regression analysis result showed that the relationship between RPM-SO4 was significantly (R2=0.66215) correlated. This indicate that probably the secondary aerosols such as nitrate and sulfate in excess may cause irritation and increasing lung disease.

Interpreting epithelial cell abnormalities detected during cervical smear screening--a cytohistologic approach.

PURPOSE: To determine the underlying pathology and clinical significance of epithelial cell abnormalities (ECA) identified during cervical Papanicolaou (Pap) smear screening. MATERIAL AND METHODS: A total of 19,215 Pap smears stained by Papanicolaou stain were screened during a 36-month period. They were classified according to The Bethesda System (TBS) for cervical cytology screening and the results of ECA were compared with histology. The chi square test was applied to determine the significance and validity of high-grade lesions on cytology diagnosis. RESULT: 360 cases of ECA were identified. Mean age at presentation was 50.58 years. Cytohistologic correlation of ECA was possible in n = 249 (69.17%) of cases. Out of these, 18 cases were negative, six were inflammatory, three were benign, and 222 cases showed pathology ranging from mild dysplasia to invasive carcinoma. The chi square test showed a highly significant predictive value (p < 0.001) for high-grade lesions detected on Pap smears. CONCLUSION: Pap smear results of high-grade squamous intraepithelial lesions (HSIL) or invasive malignancy are highly reliable and the patient may be considered directly for therapeutic intervention. Of cytologically detected ASCUS cases 38.89% were diagnosed as CIN (1-3) on histology. Thus the management of these patients needs to be re-evaluated. Atypical glandular cells of undetermined significance (AGUS) detected in postmenopausal women signify an underlying pathology. These patients should be further investigated and followed to biopsy if necessary.

Erosion of nails following thallium poisoning: a case report.

This case report describes a patient with thallium poisoning caused by repeated exposure to low doses of thallium. Alopecia and nail changes were the most prominent features of this case. There was dystrophy of nails in the form of whitish lunular stripes. This is the first report of complete erosion of proximal parts of nails following thallium poisoning. This case is the first report of thallium poisoning from India occurring from repeated low dose exposure.

Reduced dendritic spine density on cerebral cortical pyramidal neurons in schizophrenia.

OBJECTIVE: A pilot study of the density of dendritic spines on pyramidal neurons in layer III of human temporal and frontal cerebral neocortex in schizophrenia. METHODS: Postmortem material from a group of eight prospectively diagnosed schizophrenic patients, five archive schizophrenic patients, 11 non-schizophrenic controls, and one patient with schizophrenia-like psychosis, thought to be due to substance misuse, was impregnated with a rapid Golgi method. Spines were counted on the dendrites of pyramidal neurons in temporal and frontal association areas, of which the soma was in layer III (which take part in corticocortical connectivity) and which met strict criteria for impregnation quality. Altogether 25 blocks were studied in the schizophrenic group and 21 in the controls. If more than one block was examined from a single area, the counts for that area were averaged. All measurements were made blind: diagnoses were only disclosed by a third party after measurements were completed. Possible confounding affects of coexisting Alzheimer's disease were taken into account, as were the effects of age at death and postmortem interval. RESULTS: There was a significant (p<0.001) reduction in the numerical density of spines in schizophrenia (276/mm in control temporal cortex and 112/mm in schizophrenic patients, and 299 and 101 respectively in the frontal cortex). An analysis of variance, taking out effects of age at death and postmortem interval, which might have explained the low spine density for some of the schizophrenic patients, did not affect the significance of the results. CONCLUSION: The results support the concept of there being a defect in the fine structure of dendrites of pyramidal neurons, involving loss of spines, in schizophrenia and may help to explain the loss of cortical volume without loss of neurons in this condition, although the effect of neuroleptic drugs cannot be ruled out.

Pulmonary function status of shopkeepers of Ahmedabad exposed to autoexhaust pollutants.

The study deals with evaluation of pulmonary function status (VC, FEV1% and FEF25-75%) in Ahmedabad shopkeepers stationed near different traffic junctions and relating them with the levels of oxides of nitrogen (NOx) near these junctions categorised as Heavy, Medium and Low polluted area junctions. The pulmonary function test (PFT) values of heavy polluted and medium polluted area shopkeepers is compared with low polluted area shopkeepers. The influence of smoking habits and duration of exposure over PFT values was seen. The prevalence of airway obstruction in shopkeepers was compared with USA population. The results indicated significant impairment in FEV1% and FEF25-75% value in high polluted area shopkeepers where NOx level is much higher than TLV value. In medium polluted area, where NOx level is slightly higher than TLV value, shopkeepers demonstrated significant impairment in FEF25-75%. Smoking is found to have an additive effect. A linear increase in the prevalence of pulmonary impairment with increasing duration of exposure was evidenced. Shopkeepers exhibited higher prevalence of impairment in both smokers and non-smokers than USA population attributing it to the effect of autoexhaust pollutants. This study also denoted that FEF25-75% is an early indicator of obstruction in smaller airways which is the primary site of deposition of inhaled pollutants.

Non-occupational pneumoconiosis at high altitude villages in central Ladakh.

An epidemiological survey was carried out to investigate the occurrence of non-occupational pneumoconiosis in Ladakh, where there are no mines or industries. The clinicoradiological investigations of 449 randomly selected subjects from three villages showed typical cases of pneumoconiosis associated with progressive massive fibrosis and egg shell calcification of hilar glands. The prevalence of pneumoconiosis in these three villages was 2.0%, 20.1% and 45.3% and it corresponded with the severity of dust storms and the use of chimneys in the kitchens. The dust concentrations in the kitchens with no provision for a chimney were very high. The free silica content of the storms was between 60 and 70%. Exposure to free silica from dust storms and soot from domestic fuels are suggested as causes of these cases of pneumoconiosis.

Copper and zinc level in biological samples from healthy subjects of vegetarian food habit in reference to community environment.

Many epidemiologists have found a correlation between copper and zinc in the community environment and diseases, such as myocardial and vascular pathologies, and diabetes. The purpose of this study was to investigate the total daily intake of these two metals in cooked food, drinking water and air and their respective levels in blood and urine. A chronobiological methodology has been adopted to establish the reference values of these two metals in biological samples. It has been observed that the daily intake of copper is within the recommended value, whereas its urinary excretion is high. The daily intake of zinc is below the recommended value and its urinary excretion is also high. Both the metals showed a temporal oscillation pattern in blood and urine. A possible chronic zinc deficiency has been anticipated in this particular ethnic group of vegetarian food habit.

Accumulation and interrelationship of cadmium and zinc in human kidney cortex.

Cadmium and zinc have been analyzed in 102 normal human kidney cortex tissues collected from Indian hospitals. Cadmium and zinc were found to accumulate as age increased to 60 years, and had a log-normal distribution. Concentrations of cadmium and zinc in kidney cortex and cadmium/zinc ratios were comparable to those in other studies. The relationship between cadmium and zinc in kidney cortex gave a slope constant of 0.96 (YZn = 0.96XCd + 21.4).