Implicit racial biases are lower in more populous more diverse and less segregated US cities

Implicit biases - differential attitudes towards members of distinct groups - are pervasive in human societies and create inequities across many aspects of life. Recent research has revealed that implicit biases are generally driven by social contexts, but not whether they are systematically influenced by the ways that humans self-organize in cities. We leverage complex system modeling in the framework of urban scaling theory to predict differences in these biases between cities. Our model links spatial scales from city-wide infrastructure to individual psychology to predict that cities that are more populous, more diverse, and less segregated are less biased. We find empirical support for these predictions in U.S. cities with Implicit Association Test data spanning a decade from 2.7 million individuals and U.S. Census demographic data. Additionally, we find that changes in cities' social environments precede changes in implicit biases at short time-scales, but this relationship is bi-directional at longer time-scales. We conclude that the social organization of cities may influence the strength of these biases.

On the inadequacy of nominal assortativity for assessing homophily in networks

Nominal assortativity (or discrete assortativity) is widely used to characterize group mixing patterns and homophily in networks, enabling researchers to analyze how groups interact with one another. Here we demonstrate that the measure presents severe shortcomings when applied to networks with unequal group sizes and asymmetric mixing. We characterize these shortcomings analytically and use synthetic and empirical networks to show that nominal assortativity fails to account for group imbalance and asymmetric group interactions, thereby producing an inaccurate characterization of mixing patterns. We propose the adjusted nominal assortativity and show that this adjustment recovers the expected assortativity in networks with various level of mixing. Furthermore, we propose an analytical method to assess asymmetric mixing by estimating the tendency of inter- and intra-group connectivities. Finally, we discuss how this approach enables uncovering hidden mixing patterns in real-world networks.

Determinants of Bone Mineral Density in Iranian Women with Polycystic Ovary Syndrome

Background

Whether the endocrine aberrations caused by polycystic ovary syndrome (PCOS) might influence bone density in women of reproductive age is controversial.

Objectives

The present study aimed to compare PCOS women to a control group matched in terms of age and body mass index (BMI) regarding bone indices and to clarify the potential relationship between their hormonal changes and bone density.

Methods

This case-control study consisted of 61 PCOS patients, and 35 women with normal ovulatory function served as controls. Bone parameters, including bone mineral content (BMC) and bone mineral density (BMD) in addition to T- and Z-scores, were measured at the lumbar vertebrae, neck of the left femur, hip, and distal part of the radial bone, using dual-energy X-ray absorptiometry. Blood samples were taken to be tested for biochemical parameters and serum concentrations of insulin, osteocalcin, parathyroid hormone (PTH), vitamin D, follicle-stimulating hormone (FSH), luteinizing hormone (LH), total testosterone, dehydroepiandrosterone sulfate (DHEAS), and estradiol were measured. Insulin resistance was evaluated through the homeostatic model assessment of insulin resistance (HOMA-IR).

Results

The results revealed greater levels of HOMA-IR and total testosterone in PCOS women than in controls. Nevertheless, the two groups were comparable in terms of bone parameters. In the control group, BMI was the only determinant of bone density at most of the skeletal sites. Nonetheless, BMI and HOMA-IR were independently and positively associated with bone indices at the femoral neck (FN) and total hip in the PCOS group. Parathyroid hormone and vitamin D concentrations were not different in the two groups. However, phosphate levels were higher in PCOS patients (P = 0.025). Osteocalcin was inversely correlated to BMI, and both groups had a negative correlation between DHEAS and PTH. Serum phosphate was inversely and independently associated with estrogen in the PCOS group (r = -0.377, P = 0.004).

Conclusions

Body mass index and HOMA-IR were independent and positive determinants of FN and total hip bone density in the PCOS subjects. Nonetheless, in the non-PCOS women, BMI was the only independent determinant of bone density at most of the skeletal sites. Additionally, osteocalcin was inversely correlated with BMI in both groups.

Assessing the thyroid autoimmunity association with recurrent aphthous stomatitis

BACKGROUND

Recent investigations have highlighted autoimmune origins and abnormal immune responses; particularly those related to T cell-mediated immunity and elevated T lymphocyte cells in the oral mucosa. Therefore, we investigated the relationship between recurrent aphthous stomatitis (RAS) and autoimmune thyroid diseases (ATDs) in an Iranian population.

METHODS

A cross-sectional study was performed on 102 patients diagnosed with ATD (cases) and 102 healthy patients (controls) who had been referred for the routine dental treatment. All participants were asked for the history of RAS and their age, gender, other systemic diseases, medications, and frequency of RAS in a year. Matching was performed based on the propensity scores for age and sex. In addition, the number of lesions in each recurrence in both groups was assessed and compared. The type of thyroid disease has been assessed for case participants and has been confirmed by the endocrinologist. The chi-square test, t-test, and Mann-Whitney U test were used to analyze the data using SPSS 18.

RESULTS

Patients with ATD had higher RAS than healthy controls (P = 0.040). ATD patients had 1.93 times more risk for RAS, and the frequency of RAS in a year was 3.15times higher in these patients (P = 0.011). Moreover, the frequency of RAS was higher in patients with hypothyroidism than in those with hyperthyroidism. However, there were no significant differences in the size and the number of lesions between the groups.

CONCLUSION

The risk and frequency of RAS were significantly higher in patients with ATDs. This would provide valuable insights into the underlying mechanisms and potential treatment strategies for both conditions.

The effect of body position change on noninvasively acquired intracranial pulse waves

Objective. Craniospinal compliance (CC) is an important metric for the characterization of space-occupying neurological pathologies. CC is obtained using invasive procedures that carry risks for the patients. Therefore, noninvasive methods for acquiring surrogates of CC have been proposed, most recently based on changes in the head's dielectric properties during the cardiac cycle. Here, we have tested whether changes in body position, which are known to influence CC, are reflected in a capacitively acquired signal (hereinafter referred to as W) originating from dynamic changes of the head's dielectric properties. &#xD;Approach. Eighteen young healthy volunteers were included in the study. After 10 minutes in supine position, subjects were tilted head-up (HUT), back to 0° (horizontal, control), and then head-down (HDT). Metrics related to cardiovascular action were extracted from W, including AMP, the peak-to-valley amplitude of the cardiac modulation of W. Computational electromagnetic simulations were performed to probe the association between intracranial volume change and W. &#xD;Main results. AMP decreased during HUT (0°: 2869±597 arbitrary units (au); +75°: 2307±490 au, P=0.002) and increased during HDT (-30°: 4403±1428 au, P<0.0001). The same behavior was predicted by the electromagnetic model. &#xD;Significance. Tilting affects the distribution of CC between cranial and spinal compartments. Cardiovascular action induces compliance-dependent oscillatory changes in the intracranial fluid composition, which causes corresponding variations in the head's dielectric properties. These manifest as increasing AMP with decreasing intracranial compliance, which suggests that W may contain information related to CC, and that it might be possible to derive CC surrogates therefrom.

Theory for a non-invasive diagnostic biomarker for craniospinal diseases

Monitoring intracranial pressure (ICP) and craniospinal compliance (CC) is frequently required in the treatment of patients suffering from craniospinal diseases. However, current approaches are invasive and cannot provide continuous monitoring of CC. Dynamic exchange of blood and cerebrospinal fluid (CSF) between cranial and spinal compartments due to cardiac action transiently modulates the geometry and dielectric properties of the brain. The resulting impedance changes can be measured and might be usable as a non-invasive CC surrogate. A numerically robust and computationally efficient approach based on the reciprocity theorem was developed to compute dynamic impedance changes resulting from small geometry and material property changes. The approach was successfully verified against semi-analytical benchmarks, before being combined with experimental brain pulsation data to study the information content of the impedance variation. The results indicate that the measurable signal is dominated by the pulsatile displacement of the cortical brain surface, with minor contributions from the ventricular surfaces and from changes in brain perfusion. Different electrode setups result in complementary information. The information content from the investigated three electrode pairs was employed to successfully infer subject-specific brain pulsation and motion features. This suggests that non-invasive CC surrogates based on impedance monitoring could be established.

Noninvasive Monitoring of Intracranial Pulse Waves

OBJECTIVE

The clinical management of several neurological disorders benefits from the assessment of intracranial pressure and craniospinal compliance. However, the associated procedures are invasive in nature. Here, we aimed to assess whether naturally occurring periodic changes in the dielectric properties of the head could serve as the basis for deriving surrogates of craniospinal compliance noninvasively.

METHODS

We designed a device and electrodes for noninvasive measurement of periodic changes of the dielectric properties of the human head. We characterized the properties of the device-electrode-head system by measurements on healthy volunteers, by computational modeling, and by electromechanical modeling. We then performed hyperventilation testing to assess whether the measured signal is of intracranial origin.

RESULTS

Signals obtained with the device on volunteers showed characteristic cardiac and respiratory modulations. Signal oscillations can be attributed primarily to changes in resistive properties of the head during cardiac and respiratory cycles. Reduction of end-tidal CO₂, through hyperventilation, resulted in a decrease in the signal amplitude associated with cardiovascular action.

CONCLUSION

Given the higher CO₂ reactivity of intracranial vessels compared to extracranial ones, the results of hyperventilation testing suggest that the acquired signal is, in part, of intracranial origin.

SIGNIFICANCE

If confirmed in larger cohorts, our observations suggest that noninvasive capacitive acquisition of changes in the dielectric properties of the head could be used to derive surrogates of craniospinal compliance.

Inequality and inequity in network-based ranking and recommendation algorithms

Though algorithms promise many benefits including efficiency, objectivity and accuracy, they may also introduce or amplify biases. Here we study two well-known algorithms, namely PageRank and Who-to-Follow (WTF), and show to what extent their ranks produce inequality and inequity when applied to directed social networks. To this end, we propose a directed network model with preferential attachment and homophily (DPAH) and demonstrate the influence of network structure on the rank distributions of these algorithms. Our main findings suggest that (i) inequality is positively correlated with inequity, (ii) inequality is driven by the interplay between preferential attachment, homophily, node activity and edge density, and (iii) inequity is driven by the interplay between homophily and minority size. In particular, these two algorithms reduce, replicate and amplify the representation of minorities in top ranks when majorities are homophilic, neutral and heterophilic, respectively. Moreover, when this representation is reduced, minorities may improve their visibility in the rank by connecting strategically in the network. For instance, by increasing their out-degree or homophily when majorities are also homophilic. These findings shed light on the social and algorithmic mechanisms that hinder equality and equity in network-based ranking and recommendation algorithms.

[Cultural diversity in mental health care]

Background&nbsp; Of the total Dutch population, 25.7% has a migration background. The countries of origin, migration motives and time in the Netherlands are very diverse. Aim&nbsp; To provide an overview of the cultural diversity within the psychiatry of different groups of people with a migration background, and to address the challenges and mental health care to these groups and the position of transcultural psychiatry in the Netherlands. Method&nbsp; Based on integration of a narrative literature review (without a systematic search), own experiences and a fictitious case, we discuss the most important groups. This concerns the so-called guest workers as a specific group of first-generation migrants, second-generation migrants with their specific problems, and finally refugees and undocumented migrants with an accumulation of risk-increasing factors. Results&nbsp; In addition to predisposition and migration factors, insufficient understanding of cultural context contributes to the psychiatric problems of first- and second-generation migrants. Refugees and undocumented migrants also have limited access to care. There is a reimbursement system in the Netherlands for undocumented migrants, through which they can also rely on care. By understanding cultural backgrounds, professionals can further improve their skills and communication in the field of intercultural psychiatry. Conclusion&nbsp; Cultural diversity of patient groups demands additional attention to diagnosis and therapy.

Computational analysis of non-invasive deep brain stimulation based on interfering electric fields

Neuromodulation modalities are used as effective treatments for some brain disorders. Non-invasive deep brain stimulation (NDBS) via temporally interfering electric fields has emerged recently as a non-invasive strategy for electrically stimulating deep regions in the brain. The objective of this study is to provide insight into the fundamental mechanisms of this strategy and assess the potential uses of this method through computational analysis. Analytical and numerical methods are used to compute the electric potential and field distributions generated during NDBS in homogeneous and inhomogeneous models of the brain. The computational results are used for specifying the activated area in the brain (macroscopic approach), and quantifying its relationships to the stimulation parameters. Two automatic algorithms, using artificial neural network (ANN), are developed for the homogeneous model with two and four electrode pairs to estimate stimulation parameters. Additionally, the extracellular potentials are coupled to the compartmental axon cable model to determine the responses of the neurons to the modulated electric field in two developed models and to evaluate the precise activated area location (microscopic approach). Our results show that although the shape of the activated area was different in macroscopic and microscopic approaches, it located only at depth. Our optimization algorithms showed significant accuracy in estimating stimulation parameters. Moreover, it demonstrated that the more the electrode pairs, the more controllable the activated area. Finally, compartmental axon cable modeling results verified that neurons can demodulate and follow the electric field modulation envelope amplitude (MEA) in our models. The results of this study help develop the NDBS method and eliminate some limitations associated with the nonautomated optimization algorithm.

Association between serum uric acid and bone health in adolescents

Previous studies are suggestive of the protective role of uric acid on bone in the middle-aged and elderly. Whether this association exists in younger individuals has not been examined. This investigation showed a significant positive association between serum uric acid and bone parameters among Iranian adolescents.

INTRODUCTION

Uric acid (UA) might be linked to bone health, but it is unclear whether its effects on bone are limited to certain population subgroups. This study is aimed at investigating the correlation between serum uric acid levels and bone mineral density (BMD) in Iranian adolescents.

METHODS

This cross-sectional study was conducted on 413 (221 girls and 192 boys) Iranian adolescents aged 9-19 years. An analysis of anthropometric, biochemical parameters and bone density was performed on the participants. Measurements included serum uric acid, calcium, phosphorus, alkaline phosphatase, albumin, and vitamin D. They were divided according to their serum UA into the low UA group who had UA ≤ 6 mg/dL and the high UA group with UA > 6 mg/dL. BMD and bone mineral content (BMC) were measured in the total body, lumbar spine, and left femoral neck, using dual energy X-ray absorptiometry (DXA), and bone mineral apparent density (BMAD) was calculated.

RESULTS

A Pearson correlation analysis revealed a significant correlation between UA and bone parameters. In multiple regression analyses adjusted for potential confounders, serum UA was proven to be associated with BMD and BMC at all sites. There was no association between UA, serum calcium, and vitamin D concentrations.

CONCLUSION

Our study, as the first research on adolescents, demonstrated a higher bone density in those who had higher UA levels.

Pure Androgen-Secreting Adrenocortical Carcinoma Presenting with Hypoglycemia

Adrenocortical carcinoma (ACC) is a rare and aggressive malignancy. Most patients present with steroid hormone excess or abdominal mass effect. Pure androgen-secreting ACCs are rare, while hypoglycemia is an unusual presentation of this malignancy. We present a 26-year-old woman with hypoglycemia and history of adrenalectomy due to a large adrenal mass which was diagnosed as nonfunctional adrenal adenoma. She was admitted in our hospital 10 days after her fetal loss with repeated episodes of severe hypoglycemia. She had a high serum dehydroepiandrosterone sulfate (DHEA-S) and her hypoglycemia was associated with low insulin and C-peptide levels. Imaging revealed liver metastasis and immunohistochemical studies of the biopsied lesions confirmed the diagnosis of ACC.

The influence of interferon-γ on cardiac and renal histopathological changes induced by carbamazepine

BACKGROUND

Carbamazepine (CBZ) is used for the treatment of epileptic seizures. This study was designed to evaluate the effect of Interferon-gamma on the fetal heart and kidney histopathological changes of CBZ-treated pregnant mice.

METHODS

Twenty pregnant mice were divided into four groups. The control group received distilled water. The second group received 240 mg/kg of CBZ by gastric gavage. The third group received intraperitoneal injection (IP) of IFN-γ. The fourth group received IP injection of IFN-γ with 240 mg/kg CBZ by gavage. The fetuses were delivered by hysterectomy on the 18th day of gestation.

RESULTS

The mean weight, crown-rump length, the total volume of the heart and kidney of the fetuses in the CBZ-treated group were significantly reduced when compared with the control, INF-γ and CBZ + INF-γ groups (p < 0.05). INF-γ prevented histopathological changes when used with CBZ (p < 0.05).

CONCLUSION

CBZ induced structural changes in the fetal tissues of the pregnant mice. However, IFN-γ could reduce these changes (Tab. 1, Fig. 4, Ref. 26).

Effects of selenium and vitamin C on the serum level of antithyroid peroxidase antibody in patients with autoimmune thyroiditis

PURPOSE

Selenium (Se), an essential trace element, has been implicated in pathogenesis of autoimmune thyroiditis (AIT). Most studies attributed the immune modulating effects of Se to its antioxidant properties. However, there is insufficient evidence to support the use of selenium supplementation or other antioxidants in patients with AIT. This clinical trial was designed to investigate the impact of Se and vitamin C supplementation on antithyroid peroxidase antibody (TPO-Ab) level in patients with AIT.

METHODS

One hundred and two subjects aged 15-78 years were randomized into three groups. Group one (GI) (n = 38) was treated with 200 μg/day sodium selenite, group two (GII) (n = 36) received 500 mg vitamin C/day, and group three (GIII) (n = 28) received placebo over a 3-month period. Thyroid stimulating hormone (TSH), TPO-Ab, antithyroglobulin antibody (Tg-Ab) and Se concentrations were once measured before treatment and at the end of the study.

RESULTS

After 3 months, TPO-Ab concentrations decreased within Se and vitamin C-treated groups, but did not change in the placebo subjects. In this regard, there was no significant difference between the groups. We also did not find any statistically significant difference in TSH and Tg-Ab levels within and between the groups. At the end of the study, Se level was significantly higher in GI compared with GII and GIII.

CONCLUSION

Our findings supported the hypothesis of antioxidant beneficial effects of Se in AIT. However, it was not superior to vitamin C, regarding its effects on thyroid-specific antibodies.

Primary Adrenal Lymphoma Presenting with Adrenal Failure: A Case Report and Review of the Literature

INTRODUCTION

Primary adrenal lymphoma is rare, with a few cases reported in the literature. Most often it manifests as bilateral adrenal lesions and adrenal insufficiency is a common complication.

CASE PRESENTATION

A 53-year-old male was referred with abdominal discomfort and darkening of the skin since 1 month prior to admission. His workups detected large bilateral adrenal masses. The patient was admitted due to hypotension, and was diagnosed with adrenal insufficiency. Laboratory studies showed high erythrocyte sedimentation rate (ESR), lactate dehydrogenase (LDH), and adrenocorticotropin levels. There was no other organ involvement and computed tomography (CT)-guided percutaneous biopsy of the adrenal gland revealed B-cell type of non-Hodgkin lymphoma. Replacement therapy with glucocorticoid and mineralocorticoid was initiated with remission of symptoms. After 3 months of chemotherapy his condition improved, but the patient worsened thereafter and died 2 months later.

CONCLUSIONS

However, this case reminded the importance of considering primary adrenal lymphoma in the differential diagnosis of bilateral adrenal masses, especially if the patient presents with adrenal insufficiency.

Changing the dehydrogenation pathway of LiBH4–MgH2via nanosized lithiated TiO2

Nanosized lithiated titanium oxide (Li_xTiO₂) noticeably improves the kinetic behaviour of 2LiBH₄ + MgH₂.

Ca(BH4)2-Mg2NiH4: on the pathway to a Ca(BH4)2 system with a reversible hydrogen cycle

The Ca(BH4)2-Mg2NiH4 system presented here is, to the best of our knowledge, the first described Ca(BH4)2-based hydride composite that reversibly transfers boron from the Ca-based compound(s) to the reaction partner. The ternary boride MgNi2.5B2 is formed upon dehydrogenation and the formation of Ca(BH4)2 upon rehydrogenation is confirmed.

The Relationship between Organizational Trust and Organizational Silence with Job Satisfaction and Organizational Commitment of the Employees of University

<p class="apa">This study aimed to investigate the structural model between organizational trust and organizational silence with job satisfaction and organizational commitment of the employees of Islamic Azad University of Isfahan, Khorasgan branch. The study method is descriptive-correlation. The study population is the employees of Islamic Azad University of Khorasgan branch (Isfahan) as 340. 180 employees are selected by simple random method and sampling Table (Krejcie &amp; Morgan, 1970). The questionnaires of organizational trust (Ellonen et al., 2008) and organizational silence questionnaires, job satisfaction and organizational commitment (Bouradas &amp; Vakola, 2005). For analysis of study findings, Pearson correlation coefficient and structural equations modeling are applied. The results of study showed that organizational trust had inverse and significant relation with organizational silence and had positive and significant relationship with job satisfaction and organizational commitment. Also, there was an inverse and significant relationship between organizational silence and job satisfaction and organizational commitment. The results of structural equations modeling showed that organizational trust had direct impact on organizational silence (-64) organizational commitment (0.45) and job satisfaction (0.39) and has indirect impact via organizational silence on organizational commitment (0.29) and job satisfaction (0.29). Also, organizational silence had direct impact on organizational commitment and job satisfaction (-45). The model has good conditions in terms of fitness indices and fitness data.</p>

Symmetry structure in discrete models of biochemical systems: natural subsystems and the weak control hierarchy in a new model of computation driven by interactions

Interaction computing is inspired by the observation that cell metabolic/regulatory systems construct order dynamically, through constrained interactions between their components and based on a wide range of possible inputs and environmental conditions. The goals of this work are to (i) identify and understand mathematically the natural subsystems and hierarchical relations in natural systems enabling this and (ii) use the resulting insights to define a new model of computation based on interactions that is useful for both biology and computation. The dynamical characteristics of the cellular pathways studied in systems biology relate, mathematically, to the computational characteristics of automata derived from them, and their internal symmetry structures to computational power. Finite discrete automata models of biological systems such as the lac operon, the Krebs cycle and p53-mdm2 genetic regulation constructed from systems biology models have canonically associated algebraic structures (their transformation semigroups). These contain permutation groups (local substructures exhibiting symmetry) that correspond to 'pools of reversibility'. These natural subsystems are related to one another in a hierarchical manner by the notion of 'weak control'. We present natural subsystems arising from several biological examples and their weak control hierarchies in detail. Finite simple non-Abelian groups are found in biological examples and can be harnessed to realize finitary universal computation. This allows ensembles of cells to achieve any desired finitary computational transformation, depending on external inputs, via suitably constrained interactions. Based on this, interaction machines that grow and change their structure recursively are introduced and applied, providing a natural model of computation driven by interactions.

Simulating irrational human behavior to prevent resource depletion

In a situation with a limited common resource, cooperation between individuals sharing the resource is essential. However, people often act upon self-interest in irrational ways that threaten the long-term survival of the whole group. A lack of sustainable or environmentally responsible behavior is often observed. In this study, we examine how the maximization of benefits principle works in a wider social interactive context of personality preferences in order to gain a more realistic insight into the evolution of cooperation. We used time perspective (TP), a concept reflecting individual differences in orientation towards past, present, or future, and relevant for making sustainable choices. We developed a personality-driven agent-based model that explores the role of personality in the outcomes of social dilemmas and includes multiple facets of diversity: (1) The agents have different behavior strategies: individual differences derived by applying cluster analysis to survey data from 22 countries (N = 10,940) and resulting in 7 cross-cultural profiles of TP; (2) The non-uniform distribution of the types of agents across countries; (3) The diverse interactions between the agents; and (4) diverse responses to those interactions in a well-mixed population. As one of the results, we introduced an index of overall cooperation for each of the 22 countries, which was validated against cultural, economic, and sustainability indicators (HDI, dimensions of national culture, and Environment Performance Index). It was associated with higher human development, higher individualism, lower power distance, and better environmental performance. The findings illustrate how individual differences in TP can be simulated to predict the ways people in different countries solve the personal vs. common gain dilemma in the global limited-resource situation. This interdisciplinary approach to social simulation can be adopted to explain the possible causes of global environmental issues and to predict their possible outcomes.

Thyroid disorders and the prevalence of antithyroid antibodies in Shiraz population

BACKGROUND AND OBJECTIVES

Thyroid dysfunction is a common health problem affecting millions of patients worldwide. Autoimmune thyroid disorders are among the most common autoimmune disorders. In this population-based study, we assessed the prevalence of abnormal thyroid function, antithyroid antibodies and the probable relationship between them in Shiraz, southern Iran.

METHODS

Serum thyrotropin (TSH) was determined in 981 subjects (66.8% female and 33.2% male; mean age: 39.1 ± 14.3 years), who were selected with stratified random sampling. Because of the preponderance of females over males, we performed the statistical analyses using sex-weighted data (50% for each sex). Also, antithyroid peroxidase antibodies (TPOAb), and antithyroglobulin antibodies (TgAb) were measured in two random subgroups of 376 and 537 patients respectively). Thyromegaly detected on physical examination.

RESULTS

In this cross-sectional study, 8.1% of participants had elevated serum TSH level and 3.4% had low serum TSH level. A statistically significant relationship was found between gender and thyromegaly and TSH values. Positive TPOAb and positive TgAb were detected in 17% and 5.1% of participants respectively. In addition, a significant relationship was observed between elevated TSH levels and positive results for both antibodies. Detectable levels of thyroid antibodies correlated with female sex, while no correlation was observed between detectable levels of thyroid antibodies and thyromegaly.

CONCLUSION

Thyroid disorders, especially elevated TSH level, are common. It seems that autoimmune mechanisms are strongly involved in the etiology of hypothyroidism in this area.

Evaluation of verapamil efficacy in Peyronie's disease comparing with pentoxifylline

INTRODUCTION

Peyronie's disease described as penile curvature, fibromathosis and pain that occur most often in men aged 40 to 60 years. The main complaint that caused the patient to visit the clinic is nodules on the upper surface of the penis, causing curvature and distortion particularly during erection, but they don't have any urinary problem. In this study, we evaluated the effect of verapamil compared to pentoxifylline in Peyronie's disease.

METHODS

In this study, 90 patients with signs and symptoms of Peyronie's disease which were diagnosed and were in the age range 40 to 70 years enrolled. The patients were randomly divided into 3 groups. First group received pentoxifylline orally at a dose of 400 mg three times a day, in the second group verapamil (10 mg every other week for up to 12 sessions) was injected into the lesion and the third group received both treatments in combination.

RESULTS

In patients, who received pentoxifylline, curvature reduction was 26.7%, plaque size reduction was 30%, the recovery rate of erectile dysfunction was 46.7% and pain reduced was 73.3%. Each of these cases in patients, who used beta-blockers, was 36.7%, 33.3%, 66.7% and 76.6%. In combination therapy, curvature reduction was 36.7%, plaque size reduction was 33.3%, the recovery rate of erectile dysfunction was 86.7% and pain reduced was 80%.

CONCLUSION

In our study there was no significant difference between two groups using verapamil or pentoxifylline, but there was a significant improvement in combination therapy group. Due to our results we propose that combination therapy can improve results and should be considered as a choice in treatment of Peyronie's disease. 

Mathematical Modelling of Some Null-Context and Uniform Splicing Systems

The mathematical modelling of splicing system which involves recombination of DNA molecules was first introduced by Head in 1987. Splicing of DNA involves cutting of DNA molecules using the restriction enzymes and re-associating different fragments of DNA molecules using the ligase under some specific chemical conditions. A splicing language, L is generated if there exists a splicing system S for which L = L(S). There are different types of splicing systems which have been discussed by various researchers. Among them are the persistent splicing system, null-context and uniform splicing system. In this paper, some molecular examples on null-context splicing system and uniform splicing systems with different initial strings and combination of restriction enzymes will be discussed. Applications of automata theory on some molecular examples of null-context and uniform splicing languages will also be presented in this paper.

Some relations on different types of splicing systems

Splicing system is a formal characterization of the generative capacity of specified enzymatic activities acting on initial DNA molecules that was first initiated by Head in 1987. This splicing system is formally illustrated under the framework of Formal Language Theory which is a branch of Theoretical Computer Science and Applied Discrete Mathematics. There are many types of splicing systems including null-context, simple, semi-simple and seminull. In this paper, some relations for those types of splicing systems are presented.

Synthesis and application of FePt/CNTs nanocomposite as a sensor and novel amide ligand as a mediator for simultaneous determination of glutathione, nicotinamide adenine dinucleotide and tryptophan

In this study, we report the synthesis and application of a FePt/CNTs nanocomposite as a highly sensitive sensor and novel amide ligand (9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximido)-4-ethylbenzene-1,2-diol as a mediator for the determination of glutathione (GSH), nicotinamide adenine dinucleotide (NADH) and tryptophan (Trp). The synthesized materials were characterized with different methods such as NMR, IR spectroscopy, TEM, XRD, FESEM, cyclic voltammetry, electrochemical impedance spectroscopy and square wave voltammetry (SWV). The modified electrode exhibited a potent and persistent electron mediating behavior followed by well-separated oxidation peaks of GSH, NADH and Trp. The peak currents were linearly dependent on GSH, NADH and Trp concentrations in the range of 0.08-220, 1.0-400 and 5.0-500 μmol L(-1), with detection limits of 0.05, 0.8 and 1.0 μmol L(-1), respectively. The modified electrode was used for the determination of these compounds in real samples.

Genetic variation in macrophage migration inhibitory factor associated with gestational diabetes mellitus and metabolic syndrome

The aim of this study was to investigate the association of macrophage migration inhibitory factor (MIF) polymorphism rs1007888 with gestational diabetes mellitus (GDM), and its association with postpartum metabolic syndrome. In a case-control study, 147 GDM and 169 healthy pregnant patients were recruited. Blood sample was taken 2 times from all the participants; one at 24-28 weeks of gestation, second at 6-12 weeks of postpartum. Biochemical measurement and DNA extraction were performed. The PCR_SSP was performed for genotyping. The frequencies of AA, AG, and GG genotypes were 11.24% (19), 76.92% (130), and 11.83% (20) in healthy pregnancies and were 7.48% (11), 70.74% (104), and 21.76% (32) in GDM individuals. The distributions of MIF genotypes were significantly different in GDM and healthy subjects (p=0.04). Moreover, GG genotype had a significant association with pre-pregnancy obesity and family history of diabetes. In postpartum follow-up GG genotype was two-fold more frequent in women with metabolic syndrome (p=0.01, odds ratio=2.30, CI 95%; 1.23-4.30) and relative risk was equal 1.77 (CI 95%; 1.19-2.64). Our findings demonstrate an association between MIF polymorphism rs1007888 and susceptibility to GDM in pregnancy and metabolic syndrome development.

Fracture Resistance of Cuspal Coverage of Endodontically Treated Maxillary Premolars with Combined Composite-Amalgam Compared to Other Techniques

Combined composite-amalgam for cuspal coverage of endodontically treated premolars was similar to direct composite coverage in strengthening restored teeth; however, composite onlay had the highest fracture resistance.

MIF Expression in Induced Peripheral Blood Mononuclear Cells by Vitamin D3 and its Potential Correlation with Resting Metabolic Rate in Obesity

Macrophage migration inhibitory factor (MIF) plays a pivotal role in systemic and local inflammatory and immune responses. The aim of this study is to assess MIF gene expression in PBMCs harvested from obese individuals and to compare it with that of lean subjects to analyze any potential relationship between resting metabolic rate as well as several different parameters and MIF expression in PBMC. We also aim to assess anti-inflammatory characteristics of vitamin D3 on MIF expression in vitro. Participants were 30 obese and 18 non-obese subjects who were assessed following an overnight fasting for RMR by means of indirect calorimetry. Body composition was measured using a Bodystat device. The PBMCs were separated from whole blood by the Ficoll-hypaque technique. The mRNA was extracted and the cDNA was synthesized. This process was followed by real-time PCR using primer pairs specific for MIF mRNA and beta actin as internal control. Our findings clearly demonstrate that there were significant differences in terms of BMI, BMR predict, fat proportion, fat mass, free fat mass, TBW, visceral fat, fasting serum glucose, TG, HDL, Hs-CRP and RMR between the two groups. Moreover, the level of MIF expression in the obese group was approximately 2.5 times higher compared to the lean group. An increased level of MIF expression in the obese group and a decreased expression of that non-obese was observed after inducing PBMCs with vitamin D3. One of the intriguing results of this study was the observed reverse correlation between MIF expression and fat mass as well as fat proportion after PBMCs were cultured in the presence of vitamin D3. Therefore, it could be concluded that MIF expression, which is in turn influenced by vitamin D3, has a role in the hyperactive immune profile and the pro-inflammatory state observed in obese individuals which is suggested to have a causal relationship with obesity.

Tandem Repeats of the Catt Element of Macrophage Migration Inhibitory Factor Gene May Predict Gestational Diabetes Mellitus Severity

Previous investigations have demonstrated the association of the CATT repeated allele in the Macrophage migration inhibitory factor (MIF) with obesity and diabetes. Since there are common risk factors and molecular pathways in Type 2 Diabetes and Gestational Diabetes Mellitus (GDM), we focused on the associations of MIF variation with GDM. In a case-control study we enrolled 157 GDM and 217 healthy pregnant women, referred to the outpatient clinic of Shariati Hospital. The different repeats of CATT in MIF promoter were determined. MIF relative gene expression was evaluated in Peripheral blood mononuclear cells of all the participants. The GDM group had higher mean age and pre-gravid BMI. Also fasting serum glucose, insulin and MIF gene expression were significantly higher in the GDM patients. The statistically significant difference was observed between GDM and a healthy group in carrying 7-CATT allele and MIF gene expression. Regarding GDM risk factors, MIF 7-CATT allele showed significant relation with pre-pregnancy obesity, as well as the need for insulin therapy. Our results indicate that an association between MIF genotypes and its expression with GDM, obesity and the need of insulin for management of GDM patients exists.

Combination of bleach and flourescent microscopy: a milestone in the diagnosis of smear negative tuberculosis

BACKGROUND

The reliability of direct smear microscopy for diagnosis of tuberculosis has frequently been questioned due to low sensitivity. Treatment of sputum with sodium hypochlorite (NaOCI) has been used to increase sensitivity in many settings. However, no study has established the effect of NaOCI on fluorescent microscopy.

OBJECTIVE

To establish whether NaOCI concentration method enhances positivity of fluorescent microscopy smear negative sputum for diagnosis of tuberculosis.

DESIGN

A prospective study.

SETTING

Mbagathi District Hospital and Centre for Respiratory Diseases Research, Kenya Medical Research Institute.

RESULTS

Forty five (22%) specimens were culture positive. Fluorescent microscopy sensitivity was 28.9% and 22.2% after centrifugation and sedimentation with 3.5% NaOCI, respectively (P > 0.05). Sensitivity was 24.4% and 17.8% after centrifugation and sedimentation with 5% NaOCI, respectively (P > 0.05). Although there was no statistical significance difference between the two NaOCI concentration methods, 3.5% NaOCI with centrifugation indicated a higher yield.

CONCLUSION

Use of NaOCI significantly enhances positivity of smear negative sputum for diagnosis of tuberculosis when used with fluorescent microscopy. This approach could be recommended for screening all tuberculosis suspects especially in settings with potential smear negative tuberculosis.

Clinical presentation among HIV-infected and non-infected adults with community acquired pneumonia in Nairobi

SETTING

Risk factors for mortality in hospitalized patients with community-acquired pneumonia (CAP) are well known. There are limited data on prognostic indicators among out-patients.

OBJECTIVE

To compare the clinical presentation, outcome and prognostic factors for clinical improvement in human immunodeficiency virus (HIV) infected and non-HIV-infected out-patients with CAP.

METHODOLOGY

Adults in Nairobi with CAP were treated with erythromycin as first-line therapy. Clinical symptoms were evaluated using a validated CAP-related symptom score (CSS). Clinical improvement was defined as reduction of baseline CSS by > or = 50%.

RESULTS

Of 531 adults enrolled with CAP, 422 (79.5%) completed follow-up. Participants had a mean age (+/- SD) of 33.7 +/- 11.4 years, 274 (51.6%) were male and 193 (37%) were HIV-seropositive with a higher baseline CSS (27 vs. 25, P < 0.006). Overall, 196 of 422 (46%) had clinical improvement by 28 days. Factors independently associated with a longer time to clinical improvement included not being married (adjusted hazard ratio [aHR] 0.66, 95% CI 0.48-0.92) and higher baseline CSS (aHR 1.05, 95% CI 1.03-1.06).

CONCLUSIONS

HIV-infected and non-infected patients with CAP responded similarly to out-patient treatment, but HIV-infected patients were more likely to present with severe symptoms. Baseline CSS and marital status were predictive of time to clinical improvement.

Planning for PPM-DOTS implementation in urban slums in Kenya: knowledge, attitude and practices of private health care providers in Kibera slum, Nairobi

SETTING

Kibera, the largest slum in Nairobi, Kenya.

OBJECTIVE

To determine the tuberculosis (TB) knowledge, attitude and practices (KAP) of private health care providers (PHCPs) to identify their training needs and willingness to participate in a National Leprosy and Tuberculosis Control Programme (NLTP) guided TB control effort in the slum.

DESIGN AND METHODOLOGY

A cross-sectional survey. The KAP of PHCPs was assessed using an interviewer administered questionnaire.

RESULTS

Of 75 PHCPs interviewed, the majority (96.0%) were paramedics; 51 (77.1%) did not consider sputum smear microscopy crucial in patients presenting with prolonged cough or when a chest X-ray was suggestive of TB; of 29 (38.7%) who indicated familiarity with the drugs used in TB treatment, 20 (58.5%) would have chosen the NLTP-recommended regimens for the treatment of the various types of TB; 16 (21.3%) PHCPs indicated that they treated TB, six (37.5%) of whom were not familiar with anti-tuberculosis drug regimens. All the PHCPs referred TB suspects to the public sector for diagnosis.

CONCLUSION

This study reveals a significant gap in TB knowledge among the PHCPs in Kibera slum. However, given appropriate training and supervision, there is potential for public-private mix for DOTS implementation in this setting.