Balance-energy of resting state network in obsessive-compulsive disorder

Stability of the brain functional network is directly linked to organization of synchronous and anti-synchronous activities. Nevertheless, impact of arrangement of positive and negative links called links topology requires to be well understood. In this study, we investigated how topology of the functional links reduce balance-energy of the brain network in obsessive-compulsive disorder (OCD) and push the network to a more stable state as compared to healthy controls. Therefore, functional associations between the regions were measured using the phase synchrony between the EEG activities. Subsequently, balance-energy of the brain functional network was estimated based on the quality of triadic interactions. Occurrence rates of four different types of triadic interactions including weak and strong balanced, and unbalanced interactions were compared. In addition, impact of the links topology was also investigated by looking at the tendency of positive and negative links to making hubs. Our results showed although the number of positive and negative links were not statistically different between OCD and healthy controls, but positive links in OCDs' brain networks have more tendency to make hub. Moreover, lower number of unbalanced triads and higher number of strongly balanced triad reduced the balance-energy in OCDs' brain networks that conceptually has less requirement to change. We hope these findings could shed a light on better understanding of brain functional network in OCD.

Classification of code-modulated visual evoked potentials using adaptive modified covariance beamformer and EEG signals

OBJECTIVE

In general, brain computer interface (BCI) studies based on code-modulated Visual Evoked Potentials (c-VEP) use m-sequences to decode EEG responses to visual stimuli. BCI systems based on the c-VEP paradigm can simultaneously present a large number of commands, which results in a significantly high information transfer rate (ITR). Spatiotemporal beamforming (STB) is one of the commonly used approaches in c-VEP-based BCI systems.

APPROACH

In the current work, a novel STB-based technique is proposed to detect the gazed targets. The proposed method improves the performance of conventional STB-based techniques by providing a robust estimation of the covariance matrix in short stimulation times. Different user parameter-free methods, including the convex combination (CC), the general linear combination (GLC), and the modified versions of these techniques, are used to estimate a reliable and robust covariance matrix when a small number of repetitions are available.

MAIN RESULTS

The stimulus presentation rate of 120 Hz is used to assess the performance of the proposed structures. Our proposed methods improved the classification accuracy by an average of 20% compared to the conventional STB method at the shortest stimulation time. The proposed method achieves an average ITR of 157.07 bits/min by using only two repetitions of the m-sequences.

SIGNIFICANCE

The results show that our proposed methods perform significantly better than the conventional STB technique in all stimulation times.

Optimization of energy consumption per kg of pure meat by electrical and thermal systems in broiler chicken farms

ABSTRACT The present study was conducted to investigate the effect of electrical and thermal systems optimization on energy consumption in broiler farms. Experiments were conducted in 4 different climates (cold, hot, dry, and temperate) with four treatments (4 broiler farms in each region) and 5 iterations (5 rearing periods per farm) on the Ross 308 strain of broiler chicken in a completely randomized basic design. The results showed that the solutions applied in cold and dry climates had a significant effect on reducing energy consumption (P<0.05). In the hot climate, although the reduction in energy consumption was observed after the application of the solutions, the difference was not statistically significant (P>0.05). Also, the application of solutions in temperate climates created a significant difference in the specific amount of thermal energy consumption per kilo of meat and total energy (P<0.05). Overall, the results of the present experiment showed that optimizing the electrical and thermal systems of broiler houses could reduce energy consumption in all climates.

Automatic detection of epileptic seizures using Riemannian geometry from scalp EEG recordings

This paper proposes a new framework for epileptic seizure detection using non-invasive scalp electroencephalogram (sEEG) signals. The major innovation of the current study is using the Riemannian geometry for transforming the covariance matrices estimated from the EEG channels into a feature vector. The spatial covariance matrices are considered as features in order to extract the spatial information of the sEEG signals without applying any spatial filtering. Since these matrices are symmetric and positive definite (SPD), they belong to a special manifold called the Riemannian manifold. Furthermore, a kernel based on Riemannian geometry is proposed. This kernel maps the SPD matrices onto the Riemannian tangent space. The SPD matrices, obtained from all channels of the segmented sEEG signals, have high dimensions and extra information. For these reasons, the sequential forward feature selection method is applied to select the best features and reduce the computational burden in the classification step. The selected features are fed into a support vector machine (SVM) with an RBF kernel to classify the feature vectors into seizure and non-seizure classes. The performance of the proposed method is evaluated using two long-term scalp EEG (CHB-MIT benchmark and private) databases. Experimental results on all 23 subjects of the CHB-MIT database reveal an accuracy of 99.87%, a sensitivity of 99.91%, and a specificity of 99.82%. In addition, the introduced algorithm is tested on the private sEEG signals recorded from 20 patients, having 1380 seizures. The proposed approach achieves an accuracy, a sensitivity, and a specificity of 98.14%, 98.16%, and 98.12%, respectively. The experimental results on both sEEG databases demonstrate the effectiveness of the proposed method for automated epileptic seizure detection, especially for the private database which has noisier signals in comparison to the CHB-MIT database. Graphical Abstract Block diagram of the proposed epileptic seizure detection algorithm.

Automatic seizure detection using orthogonal matching pursuit, discrete wavelet transform, and entropy based features of EEG signals

BACKGROUND AND OBJECTIVE

Epilepsy is a prevalent disorder that affects the central nervous system, causing seizures. In the current study, a novel algorithm is developed using electroencephalographic (EEG) signals for automatic seizure detection from the continuous EEG monitoring data.

METHODS

In the proposed methods, the discrete wavelet transform (DWT) and orthogonal matching pursuit (OMP) techniques are used to extract different coefficients from the EEG signals. Then, some non-linear features, such as fuzzy/approximate/sample/alphabet and correct conditional entropy, along with some statistical features are calculated using the DWT and OMP coefficients. Three widely-used EEG datasets were utilized to assess the performance of the proposed techniques.

RESULTS

The proposed OMP-based technique along with the support vector machine classifier yielded an average specificity of 96.58%, an average accuracy of 97%, and an average sensitivity of 97.08% for different types of classification tasks. Moreover, the proposed DWT-based technique provided an average sensitivity of 99.39%, an average accuracy of 99.63%, and an average specificity of 99.72%.

CONCLUSIONS

The experimental findings indicated that the proposed algorithms outperformed other existing techniques. Therefore, these algorithms can be implemented in relevant hardware to help neurologists with seizure detection.

Evaluation of thermal energy consumption in broiler farms and saving strategies

ABSTRACT The aim of this study was to evaluate thermal energy consumption in broiler farms and provide solutions to reduce it. This study was performed with a completely randomized design under 4 climatic conditions, including Ardabil (cold climate representative), Khuzestan (warm climate representative), Isfahan (dry climate representative) and Guilan (temperate climate representative) in 4 replicates (4 broiler farms in each climate) and with 5 repetitions (5 periods of breeding per unit) and a capacity of 492,700, Ross 308 broiler in each breeding period. According to the results, in all climates, the proposed solutions to save thermal energy were able to create a significant difference (P<0.05). The experimental results also showed that the difference in thermal energy consumption in cold and dry climates wasmuch higher than in temperate and warm climates (P<0.05). Overall, the results of the present study show that, by optimizing andmodernizing construction equipment in broiler farms, thermal energy losses can be reduced in all climatic conditions.

Performance evaluation of the spectral autocorrelation function and autoregressive models for automated sleep apnea detection using single-lead ECG signal

BACKGROUND AND OBJECTIVE

This paper addresses the automated recognition of obstructive sleep apnea (OSA) from the analysis of single-lead ECG signals. This is one of the most important problems that is, critical to the realization of monitoring patients with sleep apnea.

METHODS

In the present study, a novel solution based on autoregressive (AR) modeling of the single-lead ECG, and spectral autocorrelation function as an ECG feature extraction method is presented. The more effective features are opted by sequential forward feature selection (SFFS) technique and fed into the random forest for binary classification between the apnea and normal events.

RESULTS

Experimental results on Apnea-ECG database proved that the introduced algorithm resulted in an accuracy of 93.90% (sensitivity of 92.26% and specificity of 94.92%) in per-segment classification, which outperforms the other cutting-edge automatic OSA recognition techniques. Moreover, the proposed algorithm provided an accuracy of 97.14% (sensitivity of 95.65% and specificity of 100%) in discrimination of apnea patients from the normal subjects, which is comparable to the traditional and existing approaches.

CONCLUSIONS

This study suggests that automatic OSA recognition from single-lead ECG signals is possible, which can be used as an inexpensive and low complexity burden alternative to more conventional methods such as Polysomnography.

Effect of respiratory exposure to benzene, toluene, xylene and ethyl benzene on the spirometric indices in two consecutive years among the petroleum products loading workers

Introduction: Benzene, toluene, xylene and ethylbenzene (BTEX) are the most important aromatic compounds in petroleum products. Due to high vapor pressure, BTEX compounds easily change to gas form and mixed with ambient air. Petroleum products loading workers are exposed to these compounds by the inhalation of BTEX compounds. The aim of this study was to evaluate the effects of respiratory BTEX exposure on lung function indicators . Materials and Methods: A cross sectional study was conducted on petroleum products loading workers in 2015 until 2016. there were process of inclusion and exclusion in working tasks. 32 people participated in this study consciously. Eighteen samples of air was gotten in the breathing zone of workers. Sampling was performed by  indivial sampling pump 222-4 model by use of activated charcoal were taken to determine the workers' exposure to benzene, toluene, xylene and ethyl benzene. Method of sampling was 1501 NIOSH.To determine and evaluate the lung function, spirometry tests were performed according to OSHA protocols. Results: The results of analysis of samples showed that the average exposure to benzene was above the occupational exposure limit and the average exposure to ethyl benzene, toluene and xylene were below the occupational exposure limit. Lung functions indices, including FVC, FEV1, FEV1 / FVC  were reduced. Conclusion: The results showed that exposure to BTEX compounds could affect lung function indices, and reduced Lung functions indices.

Modulation of Cortical Activity by Selective Steady-State Somatosensory Stimulation

Phantom limb pain (PLP) represents a major debilitating condition for amputees. No effective therapy has been reported. Non-painful surface electrical stimulation may induce temporary significant alleviation of PLP. Preliminary results of a study attempting to design a methodology for delivery and evaluation of possible quantifiable effects at the cortical level of steady-state surface stimulation are presented for two healthy subjects. Somatosensory evoked potentials (SEP) were evaluated before and after delivery of a steady-state stimulus applied at wrist along the median nerve. Characterization of evoked sensation induced in hand by the steady-state stimuli was performed. The sensory input artificially generated by the steady-state stimuli influenced cortical activation reflected in changes in N1 and P2 components of SEP. N1 suppression and changes in P2 amplitude after steady state stimulation between 1 to 7 minutes were observed. Analysis of changes in SEP components in a larger population may contribute to defining markers of temporary cortical plastic changes driven by steady-state stimuli possibly assessing the efficacy of these stimuli when attempting to reverse cortical plastic changes following amputation and relief of PLP upon specific delivery through surface electrical stimulation in the periphery.

Overcoming Challenges of Implementing Chronic Care Model in Diabetes Management: An Action Research Approach

Background:

Reforming the health care system to improve suitable health care model for diabetic patients is essential. This study aimed to implement, identify, and overcome the challenges of implementing the Chronic Care Model in diabetes management in a clinic.

Methods:

This study is a qualitative technical action research with the Kemmis and McTaggart model including planning, action, reflection, observation, and revision plan which was conducted in the specialized polyclinic from 2015 to 2017 in Isfahan city – Iran. Data were gathered through qualitative and quantitative methods. Diabetes team and 17 patients with type 2 diabetes participated in semi-structured interviews that were purposively chosen. Qualitative data were analyzed using content analysis and then quantitative data collected.

Results:

The qualitative findings of this research are in five main categories: System design upgrade, self-management upgrade, decision support, health care organization, and clinical information system upgrade. Results of quantitative data showed that most metabolic indicators like HbA1c have statistical meaningful changes (P value < 0.05).

Conclusions:

Implementing the Chronic Care Model became feasible despite serious challenges and two groups of ready and active team and active patients were developed. The study showed that one important lost link of diabetes management is underestimating the nurses’ capabilities in the management of this disease. Inevitably, serious investment on maximum use of nurses’ knowledge and skills in improving diabetes management will help diabetes care upgrade significantly.

Automatic Detection of Obstructive Sleep Apnea Using Wavelet Transform and Entropy-Based Features From Single-Lead ECG Signal

Obstructive sleep apnea (OSA) is a prevalent sleep disorder and highly affects the quality of human life. Currently, gold standard for OSA detection is polysomnogram. Since this method is time consuming and cost inefficient, practical systems focus on the usage of electrocardiogram (ECG) signals for OSA detection. In this paper, a novel automatic OSA detection method using a single-lead ECG signal has been proposed. A nonlinear feature extraction using wavelet transform (WT) coefficients obtained by an ECG signal decomposition is employed. In addition, different classification methods are investigated. ECG signals are decomposed into eight levels using a Symlet function as a mother Wavelet function with third order. Then, the entropy-based features including fuzzy/approximate/sample/correct conditional entropy as well as other nonlinear features including interquartile range, mean absolute deviation, variance, Poincare plot, and recurrence plot are extracted from WT coefficients. The best features are chosen using the automatic sequential forward feature selection algorithm. In order to assess the introduced method, 95 single-lead ECG recordings are used. The support vector machine classifier having a radial basis function kernel leads to an accuracy of 94.63% (sensitivity: 94.43% and specificity: 94.77%) and 95.71% (sensitivity: 95.83% and specificity: 95.66%) for minute-by-minute and subject-by-subject classifications, respectively. The results show that applying entropy-based features for extracting hidden information of the ECG signals outperforms other available automatic OSA detection methods. The results indicate that a highly accurate OSA detection is attained by just exploiting the single-lead ECG signals. Furthermore, due to the low computational load in the proposed method, it can easily be applied to the home monitoring systems.

Ileal MUC2 gene expression and microbial population, but not growth performance and immune response, are influenced by in ovo injection of probiotics in broiler chickens

1. The objective of present study was to evaluate the effects of intra-amniotic injection of different probiotic strains (Bacillus subtilis, Enterococcus faecium and Pediococcus acidilactici) on the intestinal MUC2 gene expression, microbial population, growth performance and immune response in broiler chicken. 2. In a completely randomised design, different probiotic strains were injected into the amniotic fluid of the 480 live embryos (d 18 of incubation), with 4 treatments and 5 replicates. Ileal MUC2 gene expression, microbial profile, growth performance and immune response were determined. 3. Injection of probiotic strains, especially B. subtilis, had significant effect on expression of the MUC2 on d 21 of incubation and d 3 post-hatch, but not on d 19 of incubation. 4. Injection of the probiotic strains decreased significantly the Escherichia coli population and increased the lactic acid bacteria population during the first week post-hatch. 5. Inoculation of probiotics had no significant effect on antibody titres against Newcastle disease virus, antibody titres against sheep red blood cell and cell-mediated immune response of chickens compared to control. 6. In ovo injection of the probiotic strains had no significant effect on growth performance of broiler chickens. 7. It was concluded that injection of probiotic bacteria especially B. subtilis into the amniotic fluid has a beneficial effect on ileal MUC2 gene expression and bacteria population during the first week post-hatch, but has no effect on growth performance and immune response in broiler chickens.

Effects of piroxicam administration on pregnancy outcome in intrauterine insemination (IUI) cycles: a randomized clinical trial

BACKGROUND

Uterus contractibility is considered a powerful prognostic factor in predicting the embryo transfer outcome. Moreover, uterine contractions are known to be stimulated by prostaglandins which are produced by cyclooxygenase from arachidonic acid. As such, suppressing the inflammatory response and contractions using anti-inflammatory and relaxant agents is expected to result in increased success rate of embryo transfer and artificial insemination.

OBJECTIVE

To investigate the effect of piroxicam administration on the success rate in intrauterine insemination (IU) cycles in patients presenting with unexplained infertility.

MATERIALS AND METHODS

This randomized, placebo-controlled clinical trial included 260 women with unexplained infertility undergoing IUI cycles. Patients were randomly assigned to receive either piroxicam ten mg/day on days 4-6 after IUI or placebo (control group). The main outcome measures were number of IUI cycles, pregnancy, abortion, and multiple pregnancy rates.

RESULTS

The pregnancy rate was found to be 25 (19.2%) and 16 (12.3%) in piroxicam and control groups, respectively (p = 0.039). Five patients (3.8%) in piroxicam group experienced twin pregnancy whereas only three patients (2.3%) in control group had twin pregnancy (p = 0.361). The pregnancy rate per cycle was also significantly higher in those who received piroxicam as compared to controls (11.16 vs. 6.66; p = 0.021).

CONCLUSION

Administration of piroxicam after IUI is associated with decreased number of cycles, as well as increased pregnancy rate and pregnancy rate per cycle in IUI cycles. However, piroxicam did not have any effect on abortion, multiple pregnancy, and ongoing pregnancy rates.

Effects of estradiol injection on outcome of in-vitro fertilization: a randomized, double-blind, placebo controlled trial

PURPOSE

To evaluate the effects of estradiol (E2) supplementation on pregnancy outcome in patients with unexplained infertility undergoing in vitro fertilization (IVF).

MATERIALS AND METHODS

A total of 100 women with unexplained infertility and candidates for IVF, were included in this study and were randomly assigned to receive E2 supplementation or placebo during the luteal phase. The E2 serum levels in the hCG administration day and third and seventh day after ovum retrieval were measured in control group. The rate of pregnancy was also quantified and compared between the two study groups.

RESULTS

There was no significant difference between two study groups regarding baseline characteristics. E2 level decreased significantly in third (1765.34 ± 680.09; p < 0.001) and seventh (1459.66 ± 593.80; p < 0.001) days after ovum retrieval (2411.16 ± 713.52). The authors found that the serum level of E2 was significantly lower in those who received E2 supplementation at day 3 (p < 0.001) and 7 (p<0.001). However the pregnancy rate was not significantly different between two study groups (p = 0.849). In the same way, there was no significant difference between two study groups regarding the number of retrieved oocytes (p = 0.563) and number of MII oocytes (p = 0.103).

CONCLUSIONS

E2 supplementation during the luteal phase in patients with unexplained infertility undergoing IVF, is associated with decreased serum levels of E2 after hCG injection. However the fertility outcome was not affected by E2 supplementation.

Dietary but not in ovo feeding of Silybum marianum extract resulted in an improvement in performance, immunity and carcass characteristics and decreased the adverse effects of high temperatures in broilers

A total of 360 fertile eggs from a broiler breeder strain (Ross 308) were used for in ovo feeding (IOF) of 0, 100 and 200 mg/kg Silybum marianum water extract at 17.5 d of incubation. After hatching, 240 chicks were transferred to the experimental cages. The diets consisted of two types; one of them without extract and the other one containing 100 mg/kg of Silybum marianum extract. Then chicks were exposed to elevated temperatures 4°C above optimum from 7 to 28 d of age for 4 h per d and after 28 d they were kept at optimum temperature. The chicks were divided into 6 treatments with 4 replicates as a completely randomised 2 × 3 factorial design. There was no effect of IOF of Silybum marianum extract on hatchability, body weight (BW) of hatched chicks or hatched chick BW/initial egg weight ratio. Chickens fed on the diet containing the extract had the highest feed intake, daily weight gains (DWGs), final BW and lowest feed conversion ratio. At 28 d, the weights of heart, spleen and bursa of birds in the treatment groups given extract were higher, but abdominal fat weights were lower. At 42 d in those fed extract in the diet, the weights of spleen and bursa were higher and abdominal fat weights were lower than the other groups. No differences were observed between groups in body temperature before application of the higher temperature but at 21 d and 28 d the body temperature of chicks given the Silybum marianum extract was lower than the other treatments during the elevated temperatures. In birds fed on the extract in the diet, HDL and cholesterol concentrations were lowest at 28 d, whereas blood glucose levels were higher in the other treatments. At 42 d the cholesterol concentration was significantly lower in birds given extract in their diet. These results indicated that dietary feeding of Silybum marianum extract resulted in an improvement in performance, immunity and carcass characteristics and decreased the adverse effects of the higher temperatures, specifically in reducing blood fat reduction, but IOF of the extract did not have an effect.

Micro-bending based optical band-pass filter and its application in S-band Thulium-doped fiber amplifier

A new approach for filtering an optical band-pass in optical amplifier is proposed using a macro bending. The proposed filter leverages the bending loss of higher order modes at shorter wavelengths. At longer wavelengths, the filter increases fiber's bending loss as the fundamental mode 'tail' is leak out from the cladding. The combination of wavelength dependent loss at longer and shorter wavelength gives rise to the optical band-pass filter characteristic inside the fiber. The simulated spectral response of the filter is found to be in good agreement with the experimental results. Subsequently, the proposed optical band-pass filter is applied in Thulium-doped fiber amplifiers (TDFA) system for gain and noise figure enhancements. The filter functions to suppress both the amplified spontaneous emission (ASE) at 800 nm and 1800 nm wavelength regions and thus improves both gain and noise figure performances in S-band region. By bending of the gain medium, gain and noise figure of the TDFA are improved by about 2 dB and 0.5 dB respectively, within a wavelength region from 1440 and 1500 nm when the 1050 nm pump power is fixed at 250 mW.

Service quality of private hospitals: the Iranian patients' perspective

BACKGROUND

Highly competitive market in the private hospital industry has caused increasing pressure on them to provide services with higher quality. The aim of this study was to determine the different dimensions of the service quality in the private hospitals of Iran and evaluating the service quality from the patients' perspective.

METHODS

A cross-sectional study was conducted between October and November 2010 in Tehran, Iran. The study sample was composed of 983 patients randomly selected from 8 private general hospitals. The study questionnaire was the SERVQUAL questionnaire, consisting of 21 items in service quality dimensions.

RESULTS

The result of factor analysis revealed 3 factors, explaining 69% of the total variance. The total mean score of patients' expectation and perception was 4.91(SD = 0.2) and 4.02(SD = 0.6), respectively. The highest expectation and perception related to the tangibles dimension and the lowest expectation and perception related to the empathy dimension. The differences between perception and expectation were significant (p < 0.001). There was a significant difference between the expectations scores based on gender, education level, and previous hospitalization in that same hospital. Also, there was a significant difference between the perception scores based on insurance coverage, average length of stay, and patients' health conditions on discharge.

CONCLUSION

The results showed that SERVQUAL is a valid, reliable, and flexible instrument to monitor and measure the quality of the services in private hospitals of Iran. Our findings clarified the importance of creating a strong relationship between patients and the hospital practitioners/personnel and the need for hospital staff to be responsive, credible, and empathetic when dealing with patients.

Faunistic study and biodiversity of scorpions in qeshm island (persian gulf)

BACKGROUND

Scorpions are known as the most widespread poisonous creatures that cause casualties and death to human. They are distributed in tropical and subtropical areas. Among the sixteen Iranian Island in the Persian Gulf, Qeshm Island is the biggest and is located in the focus of the important internal and international commercial marinelines. Furthermore, thousands of tourists also visit the Island every year for its natural beauties and the siteseeings. The present research study was carried out during 1998-99 throughout Qeshm Island in order to know the species of scorpions, their abundance, the distribution and control strategy in order to reduce the scorpion stings and to safeguard the visitors as well as the local population.

METHODS

Collections were made randomly during the night. Samples were searched by black light and then collected by forceps. A total of 102 scorpions were captured.

RESULTS

The scorpions were identified as Buthotus jayakari numbered 42 specimens (41.17%) and B. leptochelys numbering only 7 specimens (6.86%) belonging to the family Buthidae. Androctonus crassicauda was collected in the most parts of the Island and considered as the dominant species. The sex ratio was 1:1.53 in favor of females. B. leptochelys was rare species and by far restricted in its distribution.

CONCLUSION

Considering the high population of A. crassicauda and its wide distribution, it is regarded to be responsible for the majority of scorpion stings in Qeshm Island.

Increased tracheal responsiveness to beta-adrenergic agonist and antagonist in ovalbumin-sensitized guinea pigs

Despite the controversy of bronchial responsiveness to beta2-agonist drugs in asthma, in a previous study we have shown increased responsiveness of asthmatic tracheobronchial tree to isoprenaline. Therefore, in the present study, tracheal responsiveness to isoprenaline and also beta-adrenergic receptor blockade were studied in sensitized guinea pigs. An experimental model of asthma was induced in guinea pigs by sensitization of animals with injection and inhalation of ovalbumin (OA). The responses of tracheal chains of sensitized and control animals to cumulative concentrations of isoprenaline (I) in the absence and presence of 10 nmol/l propranolol were measured, and the effective concentration of I causing 50% of maximum response (EC50 I) was obtained. The propranolol blockade (CR - 1) was calculated by: (post-propranolol EC50 I/EC50 I) - 1. Tracheal responses of sensitized and control animals to cumulative concentrations of methacholine (M) were also measured and EC50 M were obtained. The tracheal responses of sensitized guinea pig to isoprenaline was significantly higher than that of the control animals (EC50 I for sensitized and control animals were 0.24 +/- 0.04 and 0.58 +/- 0.07 micromol/l, respectively; p < 0.001). The beta-adrenergic receptor blockade by propranolol (CR - 1) was also significantly higher in sensitized guinea pigs than that of the control animals (p < 0.001). The results of this study indicate an increased tracheal response to beta-adrenergic-stimulating drug and enhancement of beta-adrenergic blockade by propranolol in the sensitized guinea pig.

Effect of clomiphene citrate on endometrium thickness and echogenic patterns

OBJECTIVE

To study the effect of clomiphene citrate (CC) on the thickness and echogenic pattern of the endometrium using vaginal sonography.

METHOD

In this experimental prospective study, CC was given to 31 women with unexplained infertility. Thickness and echo patterns of the endometrium, as well as estradiol (E2) and progesterone (P) levels, were compared in women taking CC and in control patients during both the late proliferative and midsecretory phases of the menstrual cycle.

RESULTS

Endometrial thickness was significantly thinner in women taking CC (P<0.03) than in controls during the late proliferative phase but there was no significant difference during the midsecretory phase. The endometrial echogenic patterns of women taking CC who had conceived revealed endometrial thicknesses of grade III and grade IV on midsecretory days, but these findings were not significantly different from those of women who had not conceived (P=0.3). Serum E2 level was higher in women taking CC than in the controls on both late proliferative and midsecretory days (P<0.05).

CONCLUSION

CC affects endometrium thickness on late proliferative days but not on midsecretory days, and does not alter the echogenic pattern of the endometrium.

Insulin resistance in clomiphene responders and non-responders with polycystic ovarian disease and therapeutic effects of metformin

OBJECTIVES

To evaluate the clinical features, endocrine and metabolic profiles in clomiphene (CC) responders and non-responders with polycystic ovarian disease (PCOD), and to examine the effects of metformin (MTF) on the above parameters of CC resistance.

METHODS

A prospective clinical trial was undertaken at the infertility division of a university teaching hospital. Forty-one CC responders were selected and their hormonal and clinical features were determined. Forty-one CC-resistant PCOD women were also selected and clinical features; metabolic and hormonal profiles before and after treatment with MTF 1500 mg/day for 6-8 weeks were evaluated. Women who failed to conceive were treated by CC while continuing to take MTF.

RESULTS

CC responders had higher insulin levels while non-responders were hyperinsulinemic. Menstrual irregularities improved in 30%. Mean+/-S.D. area under curve of insulin decreased from 297.58+/-191.33 to 206+/-0.1 mIU/ml per min (P=0.005). Only 39.39% ovulated and 24.24% conceived.

CONCLUSION

PCOD is associated with insulin resistance (IR) particularly in CC-resistant women. Insulin resistance and androgen levels are significantly higher in obese patients. MTF therapy improved hyperandrogenemia, IR, and pregnancy rate.

Incompatibilities of chemicals

Chemical incompatibilities are potentially significant problems where hazardous chemicals are found. A number of chemical segregation systems have been developed which provide recommendations for the separation of incompatible chemicals. Three segregation systems were identified in this study: the UN Dangerous Goods system (which uses physical hazard as the main reason for segregation and has 14 categories), the US CHRIS system (which uses chemical reactivity and has 24 categories) and a third system which uses environmental risks (and has 25 categories). These systems were combined. Merging of each system was initially problematic, but became considerably easier once certain characteristics had been defined (such as flammability or water incompatibility). This gave a final merged incompatibility table containing 100 different segregation groups. This research study showed that it was possible to combine different segregation systems based on different criteria and that more comprehensive segregation systems can be developed. These can be of use in the decision-making process about where groups of chemicals may be used, and during the use of chemicals, where chemicals should not be combined. The use of more comprehensive segregation systems will also assist in developing proper measures for their control.