Pathobiology Research
Year:2001 | Volume:4 | Issue:1|Papers Count:13

Dopamine (DA) is one of the predominant cathecolaminneurotransmitter in the mammalian brain playing its' role through the D1-and D2 - Like recptors. The dopamine-induced hyperglycemia has already been reported, but the type of receptors involved in this process is still controversial. In this study we investigated the role of D1 and D2-like receptors on the plasma glucose by specifc dopaminergic agonists and antagonists in the Albino mouse. Subcutaneous administration of apomorphine (0.25, 0.5, and 1mg/kg) induced a dose-dependent hyperglycemia. This response was decreased by the blockade of the D1 and D2 receptors by the SCH and sulpiride respectively. Activation of the D2-like receptors by high doses of the LY171555 produced a significant hyperglycemia which was reduced by the sulpiride. Stimulation of the D1- like receptors by the specific D1 agonist, SKF38393, caused an increase in the plasma glucose which was not affected by the SCH. At low doses, apomorphine and SKF induced hypoglycemia in the second and third hours after the injection.In conclusion, dopaminergic system seems to have a dual stimulatory and inhibitory effect on the plasma glucose. The exact mechanisms of the stimulatory effect, mediated by the D2-like receptors, and the inhibitory effect of the dopaminergic system needs more investigation.

Purpose: At the present time, more than 80% of the first and second deliveries are made using episiotomy, while researchers attribute many side-effects to this method. On the other hand, there are controversies over the advantages of this method, specially it's most important advantage in the prevention of severe genital tract trauma. This research was carried out to compare the frequency of the incidence of genital tract trauma between two groups undergoing episiotomy, namely routine and selective episiotomy groups.Materials and Methods: This research was carried out using the clinical trial method on 730 patients having their deliveries at Imam-Khomeni and Fatema-Zahra (AS) Hospitals of Sari.Individual cases were divided randomly in two groups of routine and selective episiotomy. All the deliveries were carried out by the obstertrics and gynechology residents. Then, a questionnaire designed to collect the patients information was filled for every patient by a midwife who didn't know which group the patient was belonged to. Then, the two groups were compared with regards to the frequency of genital tract trauma. Results: Results showed a 71.1% and 84.5% frequency of episiotomy in the selective and routine groups respectively. Statistical tests showed no significant difference between the frequency of genital tract trauma in the selective and routine groups.Comparison of the cases having episiotomy indicated that all the extensive genital tract trauma (grade 3 and 4) were in the routine group.Conclusion: The hypothesis of this research stating that: "The performance of episiotomy plays a role in the severe genital tract trauma" was proved. Hence, it is proposed that the authorities pay more attention to the performance of episiotomy being solely based on the indications followed by the proper control of perineum to reduce the frequency of episiotomy.

In the present study, 11 medium cultures alone or in combination with some antibiotics were evaluated for growth of Blastocystis hominis. In this regard, stool specimens of 25 positive patients infected with the Blastocystis hominis were cultured in the modified Locke - Egg medium, Nutrient Broth, Nitrate Broth, BHI Broth, Todd Hewitt Infusion Broth, Cholera Broth, Thioglycolate, Selenite-F, Trypticase Soy Broth, Corn Meal Agar and RPMI-1640. The results indicated that the growth rate of the Blastocystis hominis in the modified Egg & Locke medium containing the antibiotics was better than the others. To be more precise, 80% of the specimens have grown well in the modified Locke-Egg medium containing the antibiotics, whereas in the lack of the antibiotics only 20% of the cases maintained a moderate growth rate. The microorganism in the RPMI- 1640 medium, RPMI-1640 medium plus antibiotics, Trypticase Soy Broth and Trypticase Soy Broth and Trypticase Soy Broth plus antibiotics maintained 52%, 44%, 12% and 36% growth rate respectively. Blastocystis hominis in the other media has not grown well.

Using three different methods of bioassays, the pathogenicity of eight isolates of the fungus Beauveria bassiana to the larvae of the Graeter wax moth Galleria mellonella was examined. The pathogenicity of the isolates was compared in terms of LT50, LC50 and LD50 values. The isolates exhibited various patterns of pathogenicity in different bioassasys which may reflect their different abilities to breach the larval cuticle. The parallelism of the slopes of the probit regression lines and the equality of log tolerance variances at high spore concentrations supported the idea that the isolated implement similar biochemical strategies in invading the host insect. Therefore, comparisons of the relative potency values were possible. The stability and disturbance of the log tolerance variances at high and sub-lethal spore concentrations respectively imply that the more concentrated inoculum, the narrower is the array of determinant factors involved in the process of infection and vice versa. The results tram injection bioassays indicate 29 times greater potency for strongest isolole No 210 (LD50= 42 spore/larva) compared to that for the weakest isolate No. 206 (LD50= 1211 spore/ larva). The LT50 values showed great fluctuation over the experiments so that the smallest LT50 values at the highest concentration (108 spore/ml) was 3.0 days for isolate No. 251 and the largest one at lowest concentration (108 spore/ml) was 12 days for isolates No. 274. The LC50 values for the mortality responses of the larvae to the fungal isolates ranged From 2.4 x 105 to 4.5 x 107 spore/ml. The results of this study, not only indicate the involvement of a number of characteristics in the pathogenicity of the fungus towards G. Mellon Ella larvae, but also the applicability of toxicological parameters in the study of a microbial agent.

Purpose: The purpose of this study was to determine the effect of aerobic exercise on apolipoprotein A-1 (apoA- 1) as cardiovascular anti-risk factor and apolipoprotein B (apoB) as cardiovascular risk factor.Method: Twenty-three previously sedentary males were matched for age, weight, height, dietary intake, and health status. Then, they were randomly allocated to either the experimental (sample) or the control group. The training program was consisted of 8 weeks running with three sessions per week, each session having at least 30 minutes duration, with an intensity producing 70% of maximal reserved heart rate.Results: Pre- and post-training mean apoA-1 measured by immunoturbidometric method showed a small decrease in the exercise group (pre-test: 165.46±38.53 mg/dl, post-test: 157.50±31.73mg/dl, P£0.35). In addition, the control group showed a considerable but not significant reduction in the mean value of apoA-1 (pre-test: 172.1±59.49 mg/dl, post-test 145.61±23.08 mg/dl, P£0.094). On the other hand, the apo B concentration was not reduced significantly in the hoth groups (exercise: pre-test: 91.72±29.74 mg/dl, post-test: 84.7±21.6 mg/dl; cotrol: pre-test:104.21±17.84 mg/dl, post-test: 102.7±13.71mg/dl).Conclusion: According to these results an 8 week aerobic training, as described above, could not affect apo A-1 & B concentration. It seems that other factors are involved in this regard and further studies are required.

Ultrasound is a commonly used therapeutic modality for which little research has been carried out on the effect of its' different modes on the tissue extensibility. The purpose of this study was to investigate the effect of two different modes of ulrasound (continuous VS pulse), in reducing the shortening of hamstrings. Thirty healthy male adults aged 20 to 30 years (mean 23.84) were selected from a young healthy population. According to the usual standards the diagnosis was bilateral short hamstrings. Subjects received either continuous (2 W/cm2, 1MHz, 5min) or pulsed (200 microsecond burst of I MHz sine waves repeated at 1 KHz, 0.5 W/cm2, 5min) ultrasound applied over their short hamstrings. A significant difference between the mean values was observed by the Student's t-test. Comparison of the data obtained after the ultrasound treatment showed a significant increase in the extensibility of the hamstrings in the two groups, but there was also a significant difference (P<0.0001) between the continuous and pulsed ultrasound. It is concluded that the heating effect of continuous ultrasound may be more effective than nonthermal properties of ultrasound for increasing the extensibility of short connective tissue.

Alzheimer's dementia (AD) is a progressive neurodegenerative disease which in recognized as the most common form of dementia in the age of 65 years old and above. Diagnosis of this disease is based upon evaluation of cognitive skills, elimination of other dementia associated diseases and cranial CT examination. However, the definitive diagnosis is proved only by neurohistological findings. Although the etiology of the disease is unknown and its' effective treatment is not available, research in the path mechanism of the disease shows a connection between increased frequency of apolipoprotein E4 allele and later onset of AD. The objective of this study was to characterize apoipoprotein E polymorphism's in late onset of AD patients. In this regard, 100 AD patients and 100 individuals (as normal controls) were examined using the PCR method. The result showed that the E4 allele was significantly more frequent in both early and late onset groups (42%) compared to the controls (11%). This data indicates that the Apo E4 could be regarded as a risk factor for AD.

A quasi-experimental study was carried out in 1999-2000 to evaluate the effects of a play program on the anxiety of hospitalized school-age children. For this purpose 60 hospitalized school-age children at medical units of Tehran Medical Center of Children were selected using the non-accidental and accessible sampling method. Then, they were divided into the case and control groups which were matched regarding demographic factors (e.g. sex, age, ...). The data was gathered using different questionnaires covering demographic data, anxiety state inventory for children, child medical fear scale, and physiologic indicators of anxiety.After the pretest a designed play program was carried out in the case group at 3 sessions each session being 30 minutes. The results were as follows: Data analysis using the chi-square (X2) showed that the demographic factors were similar in the two groups (P > 0.05).The paired t-test indicated a significant reduction in the anxiety state after the play in the case group (P < 0.001).The paired t-test showed n0 significant variation in the anxiety state of the control group at the beginning and the end of the study.The t-test showed no significant differs between the anxiety state of the case and control groups before the play program (P > 0.05).The t-test showed a significant difference between the anxiety state of the case and control groups after the play program.There was no significant difference between the physiological indexes of anxiety between the case and control groups before the play (P > 0.05). But after the play program, the t-test showed a significant difference between the two groups regarding these indexes (P < 0.05).The paired t-test showed a significant difference between the physiological indexes of anxiety easured before and after the play program in the case group (P < 0.05).Therefore, the hypothesis of the research stating "anxiety of hospitalized school age children in case group will decrease compared with the control group was proved. Therefore, it is recommended that play, as an effective technique, can be used to reduce the anxiety of hospitalized children.

There has been an increasing number of reports of actinomyces infecting the female genital tract, particularly in women using an intrauterine contraceptive device (I.U.D) Most of findings are based on the detection of actinomyces spp. in papanicolaou smears and immunofluoresence with actynomyces antisera. Other organisms normally present in the vagina may resemble actinomyces in papanicolaou smears and if antisera are not tested against a wide range of anaerobs, cross-reactions with other bacterial species may occur.In this study microbiological techniques were' used enabling us to isolate actinomyces spp. from cervicovaginal specimens. The population was consisted of 514 women attending obstetrics and gynecology clinics. The cervico-vaginal swab specimens were obtained from two groups of women. The first group was consisted of274 users of the I.U.D and the second group was consisted of 240 women without the I.U.D. The patients had symptoms such as vaginal discharge, cervicitis, vulval irritation, pelvic pain, hemorrhage and irregular bleeding. The cervico-vaginal smears were stained with the gram stain and were screened for evidence of actinomyces like organisms. Examination of cervico-vaginal smears revealed the presence of the actinomyces-like organisms in 16.78% of the women having the I.U.D and 13.75% of the woman without the I.U.D. Actiomyces were isolated by culturing the cervico-vaginal specimen from the two groups, consisting of 50 cases (18.24%) of the women with the I.U.D, and 35 cases (14.58%) of the women without an I.U.D. The difference between the two groups of women was not statistically meaningful. Our finding indicated that the type of I.U.D is not related to the colonized actinomyces, and the organisms isolated from the both lypes of I.U.D supper devices (Cupper-T), and plastic devices (Lipps-Loop), had no significant differences.In this study we found no relationship between the duration of the use of the I.U.D and the actinomyces colonisation increase. The isolated species from the two groups were: A. Israelii (50%), A.naeslundii (35%), and A.viscosus (14%).These findings suggest that actinomyces are naturally present in genital tract of some women and the use of I.U.D has not caused a significant increase in the rate of positive actinomyces cases.

Influenza is one of the most contagious diseases in human and other animals. Previous infection with the influenza virus can be shown by showing specific antibodies to the virus. Using single radial diffusion test (SRD), haemagglutination inhibition test (HII), and viral neutralization test (VNT), we tried to detect and measure influenza virus type-S antibodies.In order to run the above tests viral antigens were first prepared in chick embyonated eggs and cell culture separately. Specific antibodies were prepared in healthy rabbits injected with the above antigens. The SRD, HII, and VNT were done using the above materials. Serum samples were tested for influenza type- S virus antibodies.The VNT was taken as the standard test and the results obtained from the other tests were compared with those of the VNT, The sensitivity and specificity of HIT and SRD were 93% and 84% , 85% and 89% respectively.