Pressure related apoptosis in neuronal cell lines

Pressure is a crucial component of the cellular environment, and can lead to pathology if it varies beyond its normal range. The increased intra-ocular pressures in acute glaucoma are associated with the loss of neurons by apoptosis. Little is known regarding the interaction between pressure and apoptosis at the level of the cell. The model developed in this study examines the effects of elevated ambient hydrostatic pressure directly upon cultured neuronal lines. Conditions were selected to be within physiological limits: 100 mmHg over and above atmospheric pressure for a period of 2 hr, as seen clinically in acute glaucoma. This system can be used to investigate pressure relatively independently of other variables. Neuronal cell line cultures (B35 and PC12) were subjected to pressure conditions in specially designed pressure chambers. Controls were treated identically, except for the application of pressure, and positive controls were treated with a known apoptotic stimulus. Apoptosis was detected by cell morphology changes and by 2 specific apoptotic markers: TUNEL (Terminal transferase dUTP Nick-End Labeling) and Annexin V. These fluorescent markers were detected and quantified by automated Laser Scanning Cytometry. All techniques showed that increased pressure was associated with a greater level of apoptosis compared to equivalent controls. Our results suggest that pressure alone may act as a stimulus for apoptosis in neuronal cell cultures. This raises the possibility of a more direct relationship at the cellular level between pressure and neuronal loss.

Effect of sulfur dioxide inhalation on erythrocyte antioxidant status and lipid peroxidation in experimental diabetes

The effect of sulfur dioxide (SO(2) ) on red cell antioxidant status and lipid peroxidation was examined in this research. Forty healthy male albino rats, aged three months, were divided into four equal groups: Control (C), SO(2) +C (CSO(2) ), diabetic (D) and SO(2) +D (DSO(2) ). Experimental diabetes mellitus was induced by i.v injection of alloxan with a dose of 50 mg/kg body weight. Ten ppm SO(2) was administered to the animals of SO(2) exposed groups in an exposure chamber for one hr/day x 7 days/wk x 6wks while other groups were exposed to filtered air in the same condition. SO(2) exposure, while markedly decreasing Cu, Zn-Superoxide dismutase (Cu, Zn-SOD) activity, significantly increased glutathione peroxidase (GSH-Px), catalase (CAT), glutathione (GSH) and glutathione-s-transferase (GST) activities and TBARS values in CSO(2) and DSO(2) groups compared with their respective control groups. From these results, it could be concluded that adaptative changes occurred in antioxidant systems that may counteract the free radical effect of SO(2) in the experimental groups.

The effects of cadmium and experimental diabetes on VEP spectral data and lipid peroxidation

Fifty-two healthy swiss male albino rats, aged three months were used in this study. They were divided into four groups: Control (C), diabetic (D), Cadmium (Cd) and diabetic + Cadmium (D + Cd) groups. Diabetic condition was induced in D and D + Cd groups by administration of alloxane (5 mg/100 g). After this treatment, Cd and D + Cd groups were injected with CdCl2 i.p. (2 mg/kg/week). At the end of the two months of experimental period, flash visual evoked potentials (FVEPs) of four groups were recorded and amplitude spectral analysis was computed by transient response-frequency characteristics (TRFC) method. Significant amplitude decrement was found in 2-4 Hz frequency band of D + Cd group in comparison with C group. On the other hand, our data showed that Cd treatment and diabetic condition caused a significant increase of lipid peroxidation in kidney, brain, retina and lens.

Effect of chronic cadmium exposure on VEP and EEG spectral components

Pregnant swiss albino rats were divided to three groups as control (C), cadmium (Cd) and non-cadmium (NCd) groups. Control animals were received tap water while the rats of Cd group were received Cd as CdC12 in their drinking water during the experimental period. On the other hand, the NCd group was given Cd during pregnancy, but given tap water after birth. Twenty-two days after birth, fourteen rats (for each group) were taken from their mothers and continued to be treated with Cd (Cd group) or tap water (C and NCd groups) for an additional 38 days. After the experimental period, flash VEPs and EEGs of three groups were recorded and amplitude spectral analysis was computed by Transient Response-Frequency characteristics (TRFC) method. The mean amplitude (dB) of 1-3.5 and 14-20 Hz frequency bands for right response whereas 1-3.5, 4-7, 8-13 and 14-20 Hz frequency bands for left response of VEPs were decreased in Cd group compared with control group. On the other hand, significant differences were observed between Cd and control groups in all the frequency bands of EEGs except 6-8 Hz.

Cadmium induced alterations in somatosensory evoked potentials

Pregnant Swiss albino rats were divided into three groups: control (C), cadmium (Cd) and non-cadmium (NCd) groups. Control animals received tap water; the Cd rats received Cd as CdCl2 in their drinking water during the experimental period, while the NCd group was given Cd during pregnancy, and given tap water after birth. Twenty-two days after birth, 15 rats (for each group) were taken from their mothers and continued to be treated with Cd (Cd group) or tap water (C and NCd groups) for an additional 38 days. After the treatment period, somatosensory evoked potentials (SEPs) of the three groups were recorded from central (Cz) referenced to frontal (Fz) following left posterior tibial nerve (PTN) stimulation. Amplitude spectra of SEPs were computed by fast Fourier transform (FFT) algorithm. There was a significant amplitude decrease in 1-3.5 Hz in the NCd group and 1-3.5 and 14-20 Hz frequency bands of the Cd group compared with the control group.

Event-related potentials in hypertriglyceridemia

Event-related potentials (ERPs) of twenty-three hypertriglyceridemic (HTG) patients and twenty-three age-matched healthy controls were recorded in two different experimental conditions that the target stimulus was counted (Test 1) or uncounted (Test 2). Latencies of each wave were inside normal limits in all patients. No differences were found in the P3b amplitudes of Test 1 case among HTG and control subjects. Amplitude spectra of ERPs were computed by transient response-frequency characteristics (TRFC) method. Their maxima were found to occupy the frequency bands of 1-2, 3-4, 5-7, 8-12, 13-20, 20.5-32 Hz. When comparing Test 1 with Test 2, significant amplitude differences were found in 1-2 and 3-4 frequency bands of controls and 1-2 and 13-20 frequency bands of patient group.

The effect of aging on spectral parameters of event-related potentials

Forty-two healthy subjects ranging in age from 20 to 73 were divided into three groups according to age; a young group (20-33 years), a middle-aged group (34-49 years) and older group (50-73 years). Event-related potentials (ERPs) of three groups were recorded in two different experimental conditions that the infrequent stimulus was counted (Test 1) or uncounted (Test 2). ERPs were elicited using infrequent and frequent stimuli as red and green lights respectively. Spectral analysis of ERPs showed that decibel (dB) values of 1-2 and 3-4 Hz in young and middle-aged groups while dB value of 1-2 Hz in older group were significantly decreased in Test 2 compared with Test 1. When the number of subjects displaying amplitude maximum in each frequency band was considered, significant differences were found in 1-2 and 5-7 Hz frequency bands of young and middle-aged groups, but no significant differences were found for older group.

ERP spectral analysis of cholesterol rich patients

Visual event-related potentials (ERPs) were studied in twenty hypercholesterolemic (HC) patients and twenty age-matched healthy controls. ERPs were recorded in two different experimental conditions that the target stimulus (red light) was counted (Test 1) or uncounted (Test 2). Amplitude spectra of ERPs were computed by transient response-frequency characteristics (TRFC) method. Their maxima were found to occupy the frequency bands of 1-2, 3-4, 5-7, 8-12, 13-20, 20.5-32 Hz. The amplitude mean (decibel) of 1-2 and 3-4 frequency bands were decreased in Test 2 compared to Test 1 in the control group, but no significant amplitude differences were found between Test 1 and Test 2 in the HC group.

The immunology of scabies

Individuals with scabies react to bites by generating a cell-mediated immune response at the bite site. This elicits a very itchy papule that is often excoriated. Sometimes ulcerated papules, vasculitis, and nodules develop as a result of other immunologic reactions in skin. Immunologic reactions mediated by antibodies of the immunoglobulin G (IgG), IgM, and especially, IgE classes may also be involved. None of these reactions have been shown to eliminate all mites from the skin surface, but locally these reactions may prevent the epidemic multiplication of scabies' organisms on the skin surface, as observed in some patients with crusted scabies.

Spectral analysis of event related potentials

Event-related brain potentials (ERPs) of twenty normal subjects with no sign of neurologic diseases were measured by applying nontarget and target stimuli as green and red lights respectively. ERPs were recorded in two experimental conditions that the target stimulus was counted (Test 1) or uncounted (Test 2). The spectral analysis of ERPs recorded for Test 1 and Test 2 were computed by using the Transient Responses Frequency Characteristics (TRFC) method. Amplitude maxima were observed in the frequency bands as indicated: 1-2, 3-4, 5-6, 7-8, 8-12, 13-20, 20.5-36, 36 Hz and higher. When we compared Test 2 with the results of Test 1, we observed a significant decrease in the amplitude mean (decibel) of 1-2 Hz frequency band (p < .05). Repeated measures ANOVAs also showed that dB values of 1-2 Hz between counted and uncounted stimuli were significantly different (p < .04). When the number of subjects displaying amplitude maximum in each frequency band was considered, we have found important differences in 1-2, 3-4 Hz and 5-6 Hz bands.