Mind In Vitro Platforms: Versatile, Scalable, Robust, and Open Solutions to Interfacing with Living Neurons

Motivated by the unexplored potential of in vitro neural systems for computing and by the corresponding need of versatile, scalable interfaces for multimodal interaction, an accurate, modular, fully customizable, and portable recording/stimulation solution that can be easily fabricated, robustly operated, and broadly disseminated is presented. This approach entails a reconfigurable platform that works across multiple industry standards and that enables a complete signal chain, from neural substrates sampled through micro-electrode arrays (MEAs) to data acquisition, downstream analysis, and cloud storage. Built-in modularity supports the seamless integration of electrical/optical stimulation and fluidic interfaces. Custom MEA fabrication leverages maskless photolithography, favoring the rapid prototyping of a variety of configurations, spatial topologies, and constitutive materials. Through a dedicated analysis and management software suite, the utility and robustness of this system are demonstrated across neural cultures and applications, including embryonic stem cell-derived and primary neurons, organotypic brain slices, 3D engineered tissue mimics, concurrent calcium imaging, and long-term recording. Overall, this technology, termed "mind in vitro" to underscore the computing inspiration, provides an end-to-end solution that can be widely deployed due to its affordable (>10× cost reduction) and open-source nature, catering to the expanding needs of both conventional and unconventional electrophysiology.

The effect of impacted third molars on second molar external root resorption, a cross-sectional cone beam computed tomography study

BACKGROUND

Third molars have the highest prevalence of impaction in teeth and can cause pathological damage on the adjacent second molars. This study aims to evaluate the effects of factors related to impacted third molars on external root resorption (ERR) in adjacent second molars using cone-beam computed tomography (CBCT).

MATERIAL AND METHODS

In CBCTs, the effect of impacted third molars on the root surface of adjacent second molars was investigated. Inclusion criteria for subjects were being older than 16 and younger than 55, presence of at least one impacted third molar and adjacent second molar. Exclusion criteria were pathology, a follicle gap greater than 5 mm, crowned second molar, severe decay, an artifact on a radiologic image, and previous surgery on the second or third molars. The investigations were made based on age range, gender, tooth inclination, Pell-Gregory classification, retention type, contact area, root formation, pericoronal width, and tooth absence on the same quadrant for potential risk factors. The collected data were statistically analyzed with R software. The Chi-Square test was used to find out any significant difference. Logistic regression analyses were done for potential risk factors for ERR.

RESULTS

A total of 437 impacted third molars and adjacent second molars were investigated using CBCT. Of these, 381 met the inclusion criteria. Mesioangular and horizontal inclination, Pell-Gregory Class B-C, contact area, and retention type were found the statistically potential risk factors for ERR.

CONCLUSIONS

The impacted third molar with horizontal or mesioangular position, and osseous retention, with Pell and Gregory Class B and C, are more likely to cause external root resorption in adjacent second molars.

Disorder to order transition in cell-ECM systems mediated by cell-cell collective interactions

Cells in functional tissues execute various collective activities to achieve diverse ordered processes including wound healing, organogenesis, and tumor formation. How a group of individually operating cells initiate such complex collective processes is still not clear. Here, we report that cells in 3D extracellular matrix (ECM) initiate collective behavior by forming cell-ECM network when the cells are within a critical distance from each other. We employed compaction of free-floating (FF) 3D collagen gels with embedded fibroblasts as a model system to study collective behavior and found a sharp transition in the amount of compaction as a function of cell-cell distance, reminiscent of phase transition in materials. Within the critical distance, cells remodel the ECM irreversibly, and form dense collagen bridges between each other resulting in the formation of a network. Beyond the critical distance, cells exhibit Brownian dynamics and only deform the matrix reversibly in a transient manner with no memory of history, thus maintaining the disorder. Network formation seems to be a necessary and sufficient condition to trigger collective behavior and a disorder-to order transition. STATEMENT OF SIGNIFICANCE: Macroscopic compaction of in vitro collagen gels is mediated by collective mechanical interaction of cells. Previous studies on cell-induced ECM compaction suggest the existence of a critical cell density and phase transition associated with this phenomenon. Cell-mediated mechanical remodeling and global compaction of ECM has mostly been studied at steady state. Our study reveals a link between a transition in cell dynamics and material microstructure as cells collectively compact collagen gels. It underscores the significance of temporal evolution of these cell-ECM systems in understanding the mechanism of such collective action and provides insights on the process from a mechanistic viewpoint. These insights can be valuable in understanding dynamic pathological processes such as, cancer progression and wound healing, as well as engineering biomaterials and regenerative tissue mimics.

The effects of laparoscopic Roux-en-Y gastric bypass and one-anastomosis gastric bypass on glycemic control and remission of type 2 diabetes mellitus: study protocol for a multi-center randomized controlled trial (the DIABAR-trial)

Background

Metabolic surgery induces rapid remission of type 2 diabetes mellitus (T2DM). There is a paucity of high level evidence comparing the efficacy of the laparoscopic Roux-en-Y gastric bypass (RYGB) and the laparoscopic one-anastomosis gastric bypass (OAGB) in glycemic control. Also, the mechanisms that drive the conversion of T2DM in severe obese subjects to euglycemia are poorly understood.

Methods

The DIABAR-trial is an open, multi-center, randomized controlled clinical trial with 10 years follow-up which will be performed in 220 severely obese patients, diagnosed with T2DM and treated with glucose-lowering agents. Patients will be randomized in a 1:1 ratio to undergo RYGB or OAGB. The primary outcome is glycemic control at 12 months follow-up. Secondary outcome measures are diverse and include weight loss, surgical complications, psychologic status and quality of life, dietary behavior, gastrointestinal symptoms, repetitive bloodwork to identify changes over time, glucose tolerance and insulin sensitivity as measured by mixed meal tests, remission of T2DM, presence of non-alcoholic fatty liver disease/non-alcoholic steatohepatitis in liver biopsy, oral and fecal microbiome, cardiovascular performance, composition of bile acids, and the tendency to develop gallstones.

Discussion

The DIABAR-trial is one of the few randomized controlled trials primarily aimed to evaluate the glycemic response after the RYGB and OAGB in severe obese patients diagnosed with T2DM. Secondary aims of the trial are to contribute to a deeper understanding of the mechanisms that drive the remission of T2DM in severe obese patients by identification of microbial, immunological, and metabolic markers for metabolic response and to compare complications and side effects of RYGB and OAGB.

Trial registration

ClinicalTrials.gov NCT03330756; date first registered: October 13, 2017.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06762-3.

Empowering engineered muscle in biohybrid pump by extending connexin 43 duration with reduced graphene oxides

Engineered skeletal muscle act as therapeutics invaluable to treat injured or diseased muscle and a "living" material essential to assemble biological machinery. For normal development, skeletal myoblasts should express connexin 43, one of the gap junction proteins that promote myoblast fusion and myogenesis, during the early differentiation stage. However, myoblasts cultured in vitro often down-regulate connexin 43 before differentiation, limiting myogenesis and muscle contraction. This study demonstrates that tethering myoblasts with reduced graphene oxide (rGO) slows connexin 43 regression during early differentiation and increases myogenic mRNA synthesis. The whole RNA sequencing also confirms that the rGO on cells increases regulator genes for myogenesis, including troponin, while decreasing negative regulator genes. The resulting myotubes generated a three-fold larger contraction force than the rGO-free myotubes. Accordingly, a valveless biohybrid pump assembled with the rGO-tethered muscle increased the fluid velocity and flow rate considerably. The results of this study would provide an important foundation for developing physiologically relevant muscle and powering up biomachines that will be used for various bioscience studies and unexplored applications.

Principles for the design of multicellular engineered living systems

Remarkable progress in bioengineering over the past two decades has enabled the formulation of fundamental design principles for a variety of medical and non-medical applications. These advancements have laid the foundation for building multicellular engineered living systems (M-CELS) from biological parts, forming functional modules integrated into living machines. These cognizant design principles for living systems encompass novel genetic circuit manipulation, self-assembly, cell-cell/matrix communication, and artificial tissues/organs enabled through systems biology, bioinformatics, computational biology, genetic engineering, and microfluidics. Here, we introduce design principles and a blueprint for forward production of robust and standardized M-CELS, which may undergo variable reiterations through the classic design-build-test-debug cycle. This Review provides practical and theoretical frameworks to forward-design, control, and optimize novel M-CELS. Potential applications include biopharmaceuticals, bioreactor factories, biofuels, environmental bioremediation, cellular computing, biohybrid digital technology, and experimental investigations into mechanisms of multicellular organisms normally hidden inside the "black box" of living cells.

Patients with rheumatic diseases are ready to use social media in clinical practice; what about rheumatologists? A cross-sectional survey

Social media can be an innovative communication method between patients and physicians that help to overcome time limitation in outpatient clinics. In this study, we investigated how patients with rheumatic diseases (RD) and physicians use and are willing to use social media platforms to communicate with each other. We used a face-to-face survey that provides information on current social media habits and communication methods of rheumatology patients and physicians. We studied 399 (135 M/262 F) patients with RD with a median age of 45 (IQR: 34) years. We also studied 55 (30 M/25F) rheumatologists with a median age of 37 (IQR:34–44) years. Among patients with RD, 288 (72%) used at least one social media site within the previous month. Facebook was the most preferred social media platform, whereas Twitter and Instagram were favored by males and higher educated patients. While 17% of the patients with RD could communicate with their physicians outside of the hospital, 94% expressed that they would like to. Most patients (74%) defined social media as a reliable source for health-related information, yet 90% declared that they would like to obtain information about their disease using face-to-face communication. Forty-two (83%) rheumatologists were using social media and reported that they already communicate or would like to communicate with their patients outside of the hospital. Internet-based mobile applications and social media platforms are promising communication and educational tools for rheumatology patients.

Development of an objective index, neural activity score (NAS), reveals neural network ontogeny and treatment effects on microelectrode arrays

Microelectrode arrays (MEAs) are valuable tools for electrophysiological analysis, providing assessment of neural network health and development. Analysis can be complex, however, requiring intensive processing of large data sets consisting of many activity parameters, leading to information loss as studies subjectively report relatively few metrics in the interest of simplicity. In screening assays, many groups report simple overall activity (i.e. firing rate) but omit network connectivity changes (e.g. burst characteristics and synchrony) that may not be evident from basic parameters. Our goal was to develop an objective process to capture most of the valuable information gained from MEAs in neural development and toxicity studies. We implemented principal component analysis (PCA) to reduce the high dimensionality of MEA data. Upon analysis, we found the first principal component was strongly correlated to time, representing neural culture development; therefore, factor loadings were used to create a single index score-named neural activity score (NAS)-reflecting neural maturation. For validation, we applied NAS to studies analyzing various treatments. In all cases, NAS accurately recapitulated expected results, suggesting viability of NAS to measure network health and development. This approach may be adopted by other researchers using MEAs to analyze complicated treatment effects and multicellular interactions.

A systems biology approach to understand gut microbiota and host metabolism in morbid obesity: design of the BARIA Longitudinal Cohort Study

INTRODUCTION

Prevalence of obesity and associated diseases, including type 2 diabetes mellitus, dyslipidaemia and non-alcoholic fatty liver disease (NAFLD), are increasing. Underlying mechanisms, especially in humans, are unclear. Bariatric surgery provides the unique opportunity to obtain biopsies and portal vein blood-samples.

METHODS

The BARIA Study aims to assess how microbiota and their metabolites affect transcription in key tissues and clinical outcome in obese subjects and how baseline anthropometric and metabolic characteristics determine weight loss and glucose homeostasis after bariatric surgery. We phenotype patients undergoing bariatric surgery (predominantly laparoscopic Roux-en-Y gastric bypass), before weight loss, with biometrics, dietary and psychological questionnaires, mixed meal test (MMT) and collect fecal-samples and intra-operative biopsies from liver, adipose tissues and jejunum. We aim to include 1500 patients. A subset (approximately 25%) will undergo intra-operative portal vein blood-sampling. Fecal-samples are analyzed with shotgun metagenomics and targeted metabolomics, fasted and postprandial plasma-samples are subjected to metabolomics, and RNA is extracted from the tissues for RNAseq-analyses. Data will be integrated using state-of-the-art neuronal networks and metabolic modeling. Patient follow-up will be ten years.

RESULTS

Preoperative MMT of 170 patients were analysed and clear differences were observed in glucose homeostasis between individuals. Repeated MMT in 10 patients showed satisfactory intra-individual reproducibility, with differences in plasma glucose, insulin and triglycerides within 20% of the mean difference.

CONCLUSION

The BARIA study can add more understanding in how gut-microbiota affect metabolism, especially with regard to obesity, glucose metabolism and NAFLD. Identification of key factors may provide diagnostic and therapeutic leads to control the obesity-associated disease epidemic.

Phase imaging with computational specificity (PICS) for measuring dry mass changes in sub-cellular compartments

Due to its specificity, fluorescence microscopy has become a quintessential imaging tool in cell biology. However, photobleaching, phototoxicity, and related artifacts continue to limit fluorescence microscopy's utility. Recently, it has been shown that artificial intelligence (AI) can transform one form of contrast into another. We present phase imaging with computational specificity (PICS), a combination of quantitative phase imaging and AI, which provides information about unlabeled live cells with high specificity. Our imaging system allows for automatic training, while inference is built into the acquisition software and runs in real-time. Applying the computed fluorescence maps back to the quantitative phase imaging (QPI) data, we measured the growth of both nuclei and cytoplasm independently, over many days, without loss of viability. Using a QPI method that suppresses multiple scattering, we measured the dry mass content of individual cell nuclei within spheroids. In its current implementation, PICS offers a versatile quantitative technique for continuous simultaneous monitoring of individual cellular components in biological applications where long-term label-free imaging is desirable.

Distinct differences in gut microbial composition and functional potential from lean to morbidly obese subjects

INTRODUCTION

The gut microbiome may contribute to the development of obesity. So far, the extent of microbiome variation in people with obesity has not been determined in large cohorts and for a wide range of body mass index (BMI). Here, we aimed to investigate whether the faecal microbial metagenome can explain the variance in several clinical phenotypes associated with morbid obesity.

METHODS

Caucasian subjects were recruited at our hospital. Blood pressure and anthropometric measurements were taken. Dietary intake was determined using questionnaires. Shotgun metagenomic sequencing was performed on faecal samples from 177 subjects.

RESULTS

Subjects without obesity (n = 82, BMI 24.7 ± 2.9 kg m^-2 ) and subjects with obesity (n = 95, BMI 38.6 ± 5.1 kg m^-2 ) could be clearly distinguished based on microbial composition and microbial metabolic pathways. A total number of 52 bacterial species differed significantly in people with and without obesity. Independent of dietary intake, we found that microbial pathways involved in biosynthesis of amino acids were enriched in subjects with obesity, whereas pathways involved in the degradation of amino acids were depleted. Machine learning models showed that more than half of the variance in body fat composition followed by BMI could be explained by the gut microbiome, composition and microbial metabolic pathways, compared with 6% of variation explained in triglycerides and 9% in HDL.

CONCLUSION

Based on the faecal microbiota composition, we were able to separate subjects with and without obesity. In addition, we found strong associations between gut microbial amino acid metabolism and specific microbial species in relation to clinical features of obesity.

Performance of fabrics for home-made masks against the spread of COVID-19 through droplets: A quantitative mechanistic study

Coronavirus Disease 2019 (COVID-19) may spread through respiratory droplets released by infected individuals during coughing, sneezing, or speaking. Given the limited supply of professional respirators and face masks, the U.S. Centers for Disease Control and Prevention (CDC) has recommended home-made cloth face coverings for use by the general public. While there have been several studies on aerosol filtration performance of household fabrics, their effectiveness at blocking larger droplets has not been investigated. Here, we ascertained the performance of 11 common household fabrics at blocking large, high-velocity droplets, using a commercial medical mask as a benchmark. We also assessed the breathability (air permeability), texture, fiber composition, and water absorption properties of the fabrics. We found that most fabrics have substantial blocking efficiency (median values >70%). In particular, two layers of highly permeable fabric, such as T-shirt cloth, blocks droplets with an efficiency (>94%) similar to that of medical masks, while being approximately twice as breathable. The first layer allows about 17% of the droplet volume to transmit, but it significantly reduces their velocity. This allows the second layer to trap the transmitted droplets resulting in high blocking efficacy. Overall, our study suggests that cloth face coverings, especially with multiple layers, may help reduce droplet transmission of respiratory infections. Furthermore, face coverings made from materials such as cotton fabrics allow washing and reusing, and can help reduce the adverse environmental effects of widespread use of commercial disposable and non-biodegradable facemasks.

Performance of fabrics for home-made masks against the spread of COVID-19 through droplets: A quantitative mechanistic study

Coronavirus Disease 2019 (COVID-19) may spread through respiratory droplets released by infected individuals during coughing, sneezing, or speaking. Given the limited supply of professional respirators and face masks, the U.S. Centers for Disease Control and Prevention (CDC) has recommended home-made cloth face coverings for use by the general public. While there have been several studies on aerosol filtration performance of household fabrics, their effectiveness at blocking larger droplets has not been investigated. Here, we ascertained the performance of 11 common household fabrics at blocking large, high-velocity droplets, using a commercial medical mask as a benchmark. We also assessed the breathability (air permeability), texture, fiber composition, and water absorption properties of the fabrics. We found that most fabrics have substantial blocking efficiency (median values >70%). In particular, two layers of highly permeable fabric, such as T-shirt cloth, blocks droplets with an efficiency (>94%) similar to that of medical masks, while being approximately twice as breathable. The first layer allows about 17% of the droplet volume to transmit, but it significantly reduces their velocity. This allows the second layer to trap the transmitted droplets resulting in high blocking efficacy. Overall, our study suggests that cloth face coverings, especially with multiple layers, may help reduce droplet transmission of respiratory infections. Furthermore, face coverings made from materials such as cotton fabrics allow washing and reusing, and can help reduce the adverse environmental effects of widespread use of commercial disposable and non-biodegradable facemasks.

Molecular characterisation and phylogenetic analysis of Marek's disease virus in Turkish layer chickens

1. There is no current data about the genotypes of Marek's disease virus (MDV) in Turkish poultry flocks; hence, this study was performed to analyse CVI988/Rispens, turkey herpesvirus (HVT) vaccine viruses and MDV field viruses as well as to perform phylogenetic analysis of MDV in Turkish layer chickens. 2. In 2017 and 2018, a total of 602 spleen samples from 49 layer flocks were collected from the Marmara, West Black Sea and Aegean regions. DNA was extracted from the spleen samples and the samples were analysed by real-time PCR probe assay to detect CVI988/Rispens and HVT vaccine viruses and MDV field strains. Samples found positive for MDV by real-time PCR were subjected to PCR using the Meq gene primers for phylogenetic analysis. 3. Amongst 49 flocks, virulent MDV was detected in nine flocks. CVI988/Rispens and HVT vaccine strains were detected in 47 flocks and HVT in all 49 flocks. Splenomegaly, hepatomegaly and tumours in the oviduct were observed in chickens of affected flocks. Virulent MDV was detected in 120 out of 602 spleen samples. Sequencing and phylogenetic analyses showed that MDVs detected in this study were closely related to MDV strains from Italy, Poland, Saudi Arabia, Iraq, India and China but showed diversity with MDV strains from Egypt and Hungary. Multiple sequence analysis of the Meq protein revealed several point mutations in deduced amino acid sequences. Interestingly, CVI988/Rispens vaccine virus from China (AF493555) showed mutations at position 66 (G66R) and 71 (S66A) along with two other vaccine strains from China (GU354326.1) and Russia (EU032468.1), in comparison with the other vaccine strain CVI988/Rispens (DQ534538). The molecular analyses of the Meq gene suggested that Turkish field strains of MDV are in the class of virulent or very virulent pathotypes. 4. The results have shown that MDV still affects poultry health, and the phylogenetic and amino acid variation data obtained will help in vaccination and control strategies.

Development of 3D neuromuscular bioactuators

Neuronal control of skeletal muscle bioactuators represents a critical milestone toward the realization of future biohybrid machines that may generate complex motor patterns and autonomously navigate through their environment. Animals achieve these feats using neural networks that generate robust firing patterns and coordinate muscle activity through neuromuscular units. Here, we designed a versatile 3D neuron-muscle co-culture platform to serve as a test-bed for neuromuscular bioactuators. We used our platform in conjunction with microelectrode array electrophysiology to study the roles of synergistic interactions in the co-development of neural networks and muscle tissues. Our platform design enables co-culture of a neuronal cluster with up to four target muscle actuators, as well as quantification of muscle contraction forces. Using engineered muscle tissue targets, we first demonstrated the formation of functional neuromuscular bioactuators. We then investigated possible roles of long-range interactions in neuronal outgrowth patterns and observed preferential outgrowth toward muscles compared to the acellular matrix or fibroblasts, indicating muscle-specific chemotactic cues acting on motor neurons. Next, we showed that co-cultured muscle strips exhibited significantly higher spontaneous contractility as well as improved sarcomere assembly compared to muscles cultured alone. Finally, we performed microelectrode array measurements on neuronal cultures, which revealed that muscle-conditioned medium enhances overall neural firing rates and the emergence of synchronous bursting patterns. Overall, our study illustrates the significance of neuron-muscle cross talk for the in vitro development of neuromuscular bioactuators.

Engineering geometrical 3-dimensional untethered in vitro neural tissue mimic

Formation of tissue models in 3 dimensions is more effective in recapitulating structure and function compared to their 2-dimensional (2D) counterparts. Formation of 3D engineered tissue to control shape and size can have important implications in biomedical research and in engineering applications such as biological soft robotics. While neural spheroids routinely are created during differentiation processes, further geometric control of in vitro neural models has not been demonstrated. Here, we present an approach to form functional in vitro neural tissue mimic (NTM) of different shapes using stem cells, a fibrin matrix, and 3D printed molds. We used murine-derived embryonic stem cells for optimizing cell-seeding protocols, characterization of the resulting internal structure of the construct, and remodeling of the extracellular matrix, as well as validation of electrophysiological activity. Then, we used these findings to biofabricate these constructs using neurons derived from human embryonic stem cells. This method can provide a large degree of design flexibility for development of in vitro functional neural tissue models of varying forms for therapeutic biomedical research, drug discovery, and disease modeling, and engineering applications.

Neuromuscular actuation of biohybrid motile bots

The integration of muscle cells with soft robotics in recent years has led to the development of biohybrid machines capable of untethered locomotion. A major frontier that currently remains unexplored is neuronal actuation and control of such muscle-powered biohybrid machines. As a step toward this goal, we present here a biohybrid swimmer driven by on-board neuromuscular units. The body of the swimmer consists of a free-standing soft scaffold, skeletal muscle tissue, and optogenetic stem cell-derived neural cluster containing motor neurons. Myoblasts embedded in extracellular matrix self-organize into a muscle tissue guided by the geometry of the scaffold, and the resulting muscle tissue is cocultured in situ with a neural cluster. Motor neurons then extend neurites selectively toward the muscle and innervate it, developing functional neuromuscular units. Based on this initial construct, we computationally designed, optimized, and implemented light-sensitive flagellar swimmers actuated by these neuromuscular units. Cyclic muscle contractions, induced by neural stimulation, drive time-irreversible flagellar dynamics, thereby providing thrust for untethered forward locomotion of the swimmer. Overall, this work demonstrates an example of a biohybrid robot implementing neuromuscular actuation and illustrates a path toward the forward design and control of neuron-enabled biohybrid machines.

Cell-to-cell influence on growth in large populations

Recent studies have revealed the importance of outlier cells in complex cellular systems. Quantifying heterogeneity in such systems may lead to a better understanding of organ engineering, microtumor growth, and disease models, as well as more precise drug design. We used the ability of quantitative phase imaging to perform long-term imaging of cell growth to estimate the "influence" of cellular clusters on their neighbors. We validated our approach by analyzing epithelial and fibroblast cultures imaged over the course of several days. Interestingly, we found that there is a significant number of cells characterized by a medium correlation between their growth rate and distance (modulus of the Pearson coefficient between 0.25-.5). Furthermore, we found a small percentage of cells exhibiting strong such correlations, which we label as "influencer" cellular clusters. Our approach might find important applications in studying dynamic phenomena, such as organogenesis and metastasis.

Phylogeny and evolution of infectious bursal disease virus circulating in Turkish broiler flocks

The emergence of new infectious bursal disease virus (IBDV) variants can threaten poultry health and production all over the world causing significant economic losses. Therefore, this study was performed to determine IBDV molecular epidemilogy, VP2 gene variation, and corresponding pathological lesions in IBDV infected chickens in Turkey. For this, 1855 bursa of Fabricius samples were collected from 371 vaccinated broiler flocks. Atrophia and haemorrhages were seen in the bursa Fabricius of very virulent IBDV (vvIBDV) infected chickens. Partial VP2 gene was sequenced and phylogenetic, recombination, and evolutionary analyses were performed. 1548 (83.5%) out of 1855 of bursa of Fabricius samples were IBDV positive and 1525 of those could be sequenced. The recombination analysis did not detect occurrence of any recombination event among the Turkish strains. Among 1525 sequenced samples, 1380 of them were found to be classical strains. Among 1380 classical strains, 1317 were similar to IBDV 2512, 11 to Faragher 52/70, 40 to 228 E, and 12 to Lukert strain. Out of 1525 reverse transcriptase ploymerase chain reaction positive samples, 144 of them were found to be similar to vvIBDV-VP2 gene reported to GenBank previously. The phylogenetic tree performed on a broad sequence dataset demonstrated grouping of vvIBDV Turkish strains in three different clusters, including sequences collected also from Iraq and Kuwait (Cluster 1), Indian (Cluster 2), and a distinct Turkish-only cluster (Cluster 3). The evolutionary rate estimation on branches/clades including Turkish strain mirrored the expected one for RNA viruses and no significant differences were found among different considered branches. In conclusion, results of this study indicate that vvIBDV strains similar to those circulating in various countries in the Middle East are present and undergoing evolution in chickens from Turkish broiler flocks. This point needs to be taken into account in planning adequate control strategies.

Ruptured cystic teratoma associated with mucinous cystadenoma in a pregnant woman

Mature cystic teratoma is the most common ovarian neoplasm. However, mucinous cystadenoma with teratoma has been very rarely reported in literature. This case report, which is very rare, describes a clinical entity not previously reported in literature. A 34-year-old pregnant woman presented in the 23rd gestational week with severe right lower quadrant pain. She was diagnosed with acute abdomen and was then treated surgically. During the surgical intervention, a spontaneously ruptured mass was detected in the right ovary. This was reported histopathologically as a mature cystic teratoma in collision with mucinous cystadenoma. To the best of our knowledge, this case report is the first to have identified a ruptured mature cystic teratoma in collision with mucinous cystadenoma in a pregnant woman.

A novel technique for in situ uniaxial tests of self-assembled soft biomaterials

We introduce a novel method to form 3D biomimetic tissues from a droplet of a cell-extracellular matrix (ECM) mixture on a sensor stage and to quantify tissue force and stiffness as a function of time under optical microscopes. This method exploits advances in micro-nano fabrication and capillarity for self-assembly and self-alignment of tissues on the stage. It allows simultaneous investigation of the microstructure of the tissue in situ while its mechanical response is quantified, thus linking tissue biophysics with physiology and revealing structural-functional properties of 3D tissues. We demonstrate the functionality of the stage by studying the mechanical behavior of different cell-collagen mixtures under mechanical, chemical and electrical stimulation. This includes force evolution in cell-free collagen during curing, myotubes differentiated from muscle cell-collagen/Matrigel ECM subjected to electrical stimulation, and fibroblast-collagen tissue subjected to cancer cell conditioned media (CM) and a Rho-kinase inhibitor, Y27632. Muscle contraction decreases with increasing frequency of electrical stimulation, and fibroblasts respond to CM by increasing contractility for a short time and completely relax in the presence of Y27632 but restore force with Y27632 washout.

Biohybrid valveless pump-bot powered by engineered skeletal muscle

Pumps are critical life-sustaining components for all animals. At the earliest stages of life, the tubular embryonic heart works as a valveless pump capable of generating unidirectional blood flow. Inspired by this elementary pump, we developed an example of a biohybrid valveless pump-bot powered by engineered skeletal muscle. Our pump-bot consists of a soft hydrogel tube connected at both ends to a stiffer polydimethylsiloxane (PDMS) scaffold, creating an impedance mismatch. A contractile muscle ring wraps around the hydrogel tube at an off-center location, squeezing the tube with or without buckling it locally. Cyclic muscle contractions, spontaneous or electrically stimulated, further squeeze the tube, resulting in elastic waves that propagate along the soft tube and get reflected back at the soft/stiff tube boundaries. Asymmetric placement of muscle ring results in a time delay between the wave arrivals, thus establishing a net unidirectional fluid flow irrespective of whether the tube is buckled or not. Flow rates of up to 22.5 μL/min are achieved by the present pump-bot, which are at least three orders of magnitude higher than those from cardiomyocyte-powered valve pumps of similar size. Owning to its simple geometry, robustness, ease of fabrication, and high pumping performance, our pump-bot is particularly well-suited for a wide range of biomedical applications in microfluidics, drug delivery, biomedical devices, cardiovascular pumping system, and more.

Development of eosinophilic granulomatosis with poliangiitis (Churg-Strauss syndrome) and brain tumor in a patient after more than 7 years of omalizumab use: A case report

Omalizumab is a monoclonal anti-immunoglobulin E antibody used for the treatment of severe perennial allergic asthma. Previous reports have suggested that omalizumab treatment can be associated with the development of eosinophilic granulomatosis with poliangiitis (EGPA) (formerly known as Churg-Strauss syndrome) and an increased risk of malignancy. Long-term risks of omalizumab treatment are not very well defined. Here, we report the case of a 75-year-old woman with concurrent occurrence of EGPA and brain tumor after more than 7 years of omalizumab treatment. The possibility of EGPA should be borne in mind during long-term treatment with omalizumab. Despite the absence of definitive data, an association may also exist between the development of malignancy and omalizumab use.

Effect of retinyl acetate on transglutaminase 2 activity in carcinogen treated rat liver

Transglutaminase 2 (TG2) has been implicated in wound healing, cellular differentiation, apoptosis and cell survival. TG2 activity increases following acute and chronic liver injury; however, the role of TG2 in tumors, is controversial. TG2 is a retinoid-inducible enzyme. We investigated the effects of retinyl acetate (RA) on the activity and levels of TG2 during the initiation and promotion stages of liver cancer. p-Dimethylaminoazobenzene (p-DAB) was used as initiator and 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) was used as promoter in our model of carcinogenesis. Rats were divided into four groups of 24: control, corn oil control, p-DAB + TCDD, and p-DAB + TCDD + RA. Six rats from each group were sacrificed at days 30, 60, 90 and 120. TG2 activity decreased in the p-DAB + TCDD treated group, but TG2 immunostaining scores did not change by days 90 and 120. Neither TG2 enzyme activity nor the immunostaining score of TG2 protein changed in the tissues of the p-DAB + TCDD + RA group by days 90 and 120. TG2 activity was not be ameliorated by RA during the initiation or promotion stages of carcinogen induced liver cancer.

Time-resolved local strain tracking microscopy for cell mechanics

A uniaxial cell stretching technique to measure time-resolved local substrate strain while simultaneously imaging adherent cells is presented. The experimental setup comprises a uniaxial stretcher platform compatible with inverted microscopy and transparent elastomer samples with embedded fluorescent beads. This integration enables the acquisition of real-time spatiotemporal data, which is then processed using a single-particle tracking algorithm to track the positions of fluorescent beads for the subsequent computation of local strain. The present local strain tracking method is demonstrated using polydimethylsiloxane (PDMS) samples of rectangular and dogbone geometries. The comparison of experimental results and finite element simulations for the two sample geometries illustrates the capability of the present system to accurately quantify local deformation even when the strain distribution is non-uniform over the sample. For a regular dogbone sample, the experimentally obtained value of local strain at the center of the sample is 77%, while the average strain calculated using the applied cross-head displacement is 48%. This observation indicates that considerable errors may arise when cross-head measurement is utilized to estimate strain in the case of non-uniform sample geometry. Finally, the compatibility of the proposed platform with biological samples is tested using a unibody PDMS sample with a well to contain cells and culture media. HeLa S3 cells are plated on collagen-coated samples and cell adhesion and proliferation are observed. Samples with adherent cells are then stretched to demonstrate simultaneous cell imaging and tracking of embedded fluorescent beads.

Effects of Ankaferd Blood Stopper and calcium alginate in experimental model of hepatic parenchymal bleeding

BACKGROUND

This experimental study compared the hemostatic effects of calcium alginate and Anka-ferd Blood Stopper in hepatic parenchymal bleedings.

MATERIAL AND METHOD

The study comprised 39 male Wistar albino rats (weight 230±30 g). Laceration model was created in the left lateral lobe of the liver. Standard cotton gauze that was impregnated 0.9% NaCl solution and Calcium alginate cover was compared to ABS tampon. The amount of preoperative bleeding, preoperative and postoperative Day 1 hematocrit levels, and the difference between them were assessed and statistically analyzed.

RESULTS

Comparing the hematocrit levels between the groups, we found that the amount of bleeding was significantly higher in the control group versus the study groups (p<0.001). Histopathological examination revealed the portal area enlargement and biliary canaliculi proliferation. In the Ca2+ Alginate group, it was observed that the fibres were still present in the incision line with massive fibrotic area around. In the Ankaferd group, examination of the preparations revealed patchy focal necrosis areas but no fibrotic area.

CONCLUSION

With this study, we demonstrated that both calcium alginate and Ankaferd have hemostatic effect in preventing hepatic parenchymal bleeding and that calcium alginate causes fibrosis in the liver, where ABS causes focal necrosis areas(Tab. 2, Fig. 4, Ref. 19).

Air leak syndrome after endoscopic retrograde cholangiopancreatography: A rare and fatal complication

Endoscopic retrograde cholangiopancreatography (ERCP) is a state of the art diagnostic and therapeutic procedure for various pancreatic and biliary problems. In spite of the well-established safety of the procedure, there is still a risk of complications such as pancreatitis, cholangitis, bleeding and perforation. Air leak syndrome has rarely been reported in association with ERCP and the optimal management of this serious condition can be difficult to establish. Our group successfully managed a case of air leak syndrome following ERCP which was caused by a 3cm Stapfer type I perforation in the posterolateral aspect of the second part of the duodenum and was repaired surgically. Hereby, we describe the presentation and subsequent therapeutic approach.

Assesment of perfusion in glial tumors with arterial spin labeling; comparison with dynamic susceptibility contrast method

PURPOSE

Arterial spin labeling perfusion imaging (ASL-PI) is a non-invasive perfusion imaging method that can be used for evaluation and quantification of cerebral blood flow (CBF). Aim of our study was to evaluating the efficiency of ASL in histopathological grade estimation of glial tumors and comparing findings with dynamic susceptibility contrast perfusion imaging (DSC-PI) method.

METHODS

This study involved 33 patients (20 high-grade and 13 low-grade gliomas). Multiphase multislice pulsed ASL MRI sequence and a first-passage gadopentetate dimeglumine T2*-weighted gradient-echo single-shot echo-planar sequence were acquired for all the patients. For each patient, perfusion relative signal intensity (rSI), CBF and relative CBF (rCBF) on ASL-PI and relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) values on DSC-PI were determined. The relative signal intensity of each tumor was determined as the maximal SI within the tumor divided by SI within symetric region in the contralateral hemisphere on ASL-PI. rCBV and rCBF were calculated by deconvolution of an arterial input function. Relative values of the lesions were obtained by dividing the values to the normal appearing symmetric region on the contralateral hemisphere. For statistical analysis, Mann-Whitney ranksum test was carried out. Receiver operating characteristic curve (ROC) analysis was performed to assess the relationship between the rCBF-ASL, rSI-ASL, rCBV and rCBF ratios and grade of gliomas. Their cut-off values permitting best discrimination was calculated. The correlation between rCBV, rCBF, rSI-ASL and rCBF-ASL and glioma grade was assessed using Spearman correlation analysis.

RESULTS

There was a statistically significant difference between low and high-grade tumors for all parameters. Correlation analyses revealed significant positive correlations between rCBV and rCBF-ASL (r=0.81, p<0.001). However correlation between rCBF and rCBF-ASL was weaker (r=0.64, p<0.001).

CONCLUSION

Arterial spin labeling is an employable imaging technique for evaluating tumor perfusion non-invasively and may be useful in differentiating high and low grade gliomas.

Positive correlation of serum parathormone and prostate specific antigen levels in prostate cancer

OBJECTIVES

Clinical and experimental observations reveal the exact role of vitamin D in prostate cancer. Yet, a complete understanding of the issue necessitates the evaluation of the exquisite mechanisms that involve full actors of the calcium homeostasis in relation.

BACKGROUND

Besides the role of vitamin D, parathyroid hormone (PTH) is now understood to be a mitogen for prostate cancer cells, and calcium has already been known for such role. The interplay between renin-angiotensin-aldosterone system effector hormones and calcium homeostasis attracts attention in recent studies.

METHODS

Twenty five patients with prostate cancer (median age 66 (62-67) years) who had presented at the Urology Outpatient Clinic were prospectively included in the study. Also, 30 volunteer controls (median age 63 (60-70) years) were enrolled for comparison. Serum total PSA, intact PTH, calcium, aldosterone and 25-hydroxy vitamin D levels were detected in a selected group of patients with prostate cancer.

RESULTS

The vitamin D levels were lower in PCa patients in line with some of the previous studies, supporting the role of vitamin D in prostate cancer. We also observed a positive correlation between PTH and PSA both in PCa patients and the controls.

CONCLUSION

Our findings indicate that like age and race, PSA is associated with PTH. The role of PTH, as a master of calcium homeostasis, seems to be neglected in prostate carcinogenesis, concerning a very few number of studies pertaining to the subject in the literature (Tab. 2, Fig. 2, Ref. 19).

How do patients with asthma and COPD behave during fasting?

BACKGROUND-OBJECTIVE

Several factors might affect the adherence to treatment in patients with asthma and COPD. Among these factors, the effect of religious beliefs and behaviours has been less studied so far. In this study, the effect of fasting on drug use behaviours of patients with asthma and COPD were comparatively analysed.

METHODS

A total of 150 adult patients with asthma and 150 adult patients with COPD were consecutively enrolled into this cross-sectional study. The patients were asked whether they fast during Ramadan and if the answer was yes, they were kindly asked to respond to further questions related to use of inhaled medications during that particular time.

RESULTS

The majority of the cases from both groups [98 (65.3%) of asthma patients and 139 (92.6%) of COPD] were fasting during Ramadan. The majority of the patients with COPD (n=126; 90.6%) reported that they quitted their regular therapy basis during Ramadan. On the other hand, the majority of asthma patients used their controller inhaled medications during Ramadan and preferred to use them on iftar and sahur times (n=81, 82.6%).

CONCLUSION

Our results showed that in a Muslim population, the patients with asthma and COPD do not feel their diseases to be an inhibitory factor for fasting during Ramadan. However, fasting seems to be an important determining factor in medication compliance by modifying the drug use behaviours in each group in a different way. Therefore, the patients should be informed about the effects of fasting on their disease and the allowed drugs during fasting.

Liver involvement in patients with brucellosis: results of the Marmara study

Brucellosis is a zoonotic disease that primarily affects the reticuloendothelial system. But, the extent of liver damage in due course of the disease is unclear. This study included 325 brucellosis patients with significant hepatobiliary involvement identified with microbiological analyses from 30 centers between 2000 and 2013. The patients with ≥5 times of the upper limit of normal for aminotransferases, total bilirubin level ≥2 mg/dl or local liver lesions were enrolled. Clinical hepatitis was detected in 284 patients (87.3 %) and cholestasis was detected in 215 (66.1 %) patients. Fatigue (91 %), fever (86 %), sweating (83 %), arthralgia (79 %), and lack of appetite (79 %) were the major symptoms. Laboratory tests showed anemia in 169 (52 %), thrombocytopenia in 117 (36 %), leukopenia in 81 (25 %), pancytopenia in 42 (13 %), and leukocytosis in 20 (6 %) patients. The most commonly used antibiotic combinations were doxycycline plus an aminoglycoside (n = 73), doxycycline plus rifampicin (n = 71), doxycycline plus rifampicin and an aminoglycoside (n = 27). The duration of ALT normalization differed significantly in three treatment groups (p < 0.001). The use of doxycycline and an aminoglycoside in clinical hepatitis showed better results compared to doxycycline and rifampicin or rifampicin, aminoglycoside, doxycycline regimens (p < 0.05). However, the length of hospital stay did not differ significantly between these three combinations (p > 0.05). During the follow-up, treatment failure occurred in four patients (1 %) and relapse was seen in three patients (0.9 %). Mortality was not observed. Hepatobiliary involvement in brucellosis has a benign course with suitable antibiotics and the use of doxycycline and an aminoglycoside regimen seems a better strategy in select patients.

Diagnostic value of thiols, paraoxonase 1, arylesterase and oxidative balance in colorectal cancer in human

Oxidative stress has been shown to play an important role in carcinogenesis. We hypothesize that serum oxidative and anti-oxidative factors work together to influence colon and rectal cancer through an oxidative balance mechanism. Total thiol (Ttl) is considered a plasma antioxidant and high density lipoprotein (HDL)- dependent paraoxonase l (PON1) is known as a free radical scavenger. This study was undertaken to determine the activity of PON1, arylesterase (ARE) and Ttl levels and oxidative balance in colorectal cancer (CRC) patients and healthy subjects.Paraoxonase and arylesterase activities of the HDL-dependent PON1 enzyme and the level of Ttl, total oxidant status (TOS) ,total antioxidant status (TAS) in forty patients with CRC (19 female, 21 male; mean age, 56.5 ± 2.1) and thirty-nine age and sex matched healthy persons (22 female, 17 male; mean age 56 ± 1.7) were studied.PON1 and ARE activities were significantly lower in patients with CRC compared to controls (p<0.001 for each), whereas oxidant parameters (TOS and OSI) were significantly higher in CRC patients (p<0.001 for each). However, TAS and Ttl significantly decreased in patients with CRC (p=0.03 and p<0.0001, respectively). According to the ROC curve analysis, Ttl was superior to other parameters in terms of diagnostic sensitivity and specificity which were 97.5% and 92.3%, respectively, and the AUC 0.97 in CRC patients. Decreased Ttl and HDL-dependent PON 1 enzyme activities and high TOS levels imply an imbalance of the free radical system which enhances the support the hypothesis that CRC is associated with excess reactive oxygen species.These findings show that of serum oxidative imbalance was associated with an increased risk of CRC. To our knowledge, this is the first report demonstrating lower serum PON1, ARE activities in CRC patients. The mechanism behind this association needs further elucidation.

Prevalence of aspirin-exacerbated respiratory disease in patients with asthma in Turkey: a cross-sectional survey

BACKGROUND

There are no country-based data focused on aspirin (ASA)-exacerbated respiratory disease (AERD) in Turkey.

OBJECTIVE

To assess the prevalence of AERD in adult patients with asthma.

METHODS

A structured questionnaire was administered via face-to-face interview by a specialist in pulmonology/allergy at seven centres across Turkey.

RESULTS

A total of 1344 asthma patients (F/M: 1081/263: 80.5%/19.5%, mean age: 45.7 ± 14.2 years) were enrolled. Atopy rate was 47%. Prevalence of allergic rhinitis, chronic rhinosinusitis/rhinitis, and nasal polyposis (NP) were 49%, 69% and 20%, respectively. Of 270 patients with NP, 171 (63.3%) reported previous nasal polypectomy and 40 (25%) had a history of more than three nasal polypectomies. Aspirin hypersensitivity was diagnosed in 180 (13.6%) asthmatic patients, with a reliable history in 145 (80.5%), and oral ASA provocation test in 35 (19.5%) patients. Clinical presentations of ASA hypersensitivity were respiratory in 76% (n=137), respiratory/cutaneous in 15% (n=27), and systemic in 9% (n=16) of the patients. Multivariate analysis indicated that a family history of ASA hypersensitivity (p: 0.001, OR: 3.746, 95% CI: 1.769-7.929), history of chronic rhinosinusitis/rhinitis (p: 0.025, OR: 1.713, 95% CI: 1.069-2.746) and presence of NP (p<0.001, OR: 7.036, 95% CI: 4.831-10.247) were independent predictors for AERD.

CONCLUSION

This cross-sectional survey showed that AERD is highly prevalent among adult asthmatics and its prevalence seems to be affected by family history of ASA hypersensitivity, history of rhinosinusitis and presence of NP.

A comparison of the effectiveness of talc, polidocanol and ethanol as pleural sclerosing agents in rabbits

BACKGROUND

Aim of the study was to compare the pleurodesis results from the intrapleural injection of talc, polidocanol and ethanol into the rabbit pleura.

METHODS

Twenty-nine New Zealand white rabbits were randomized into three groups for the intrapleural administration of 200 mg/kg (n = 10) of talc, 15 mg/kg (n = 10) of 3 % polidocanol or 1 mL (n = 9) of 4.2 % ethanol in 2 mL saline solution, respectively. The pleural spaces were assessed grossly for evidence of pleurodesis and microscopically for evidence of inflammation, thickness, cellularity, neovascularity and mesothelial cell proliferation in both pleura.

RESULTS

The mean degrees of gross pleurodesis were 2.0 +/- 0.66 (on a scale from 0 to 4) for talc, 2.2 +/- 0.91 for polidocanol and 0.7 +/- 0.86 for ethanol. The parietal pleura thickness was 191 +/- 213.6 microm, 236 +/- 224.6 microm and 45 +/- 44.2 microm, while the visceral pleura thickness was 109 +/- 103.7 microm, 164 +/- 161.4 microm and 48 +/- 42.2 microm in the talc, polidocanol and ethanol groups, respectively. The results of microscopic examination were similar in the talc and polidocanol groups.

CONCLUSION

The intrapleural injection of polidocanol produces better pleurodesis than does the intrapleural injection of talc or ethanol in rabbits. Because of the efficacy of polidocanol as a sclerosing agent, its use in humans should be considered after further animal studies.

Ovarian enlargement associated with massive oedema

Massive ovarian oedema is a rare entity described as accumulation of oedema fluid within the ovarian stroma, separating normal follicular structures. Our case was a 27-year-old woman who presented with a large solid pelvic mass after recurrent episodes of self-limited abdominal pain. On physical examination, she had left abdominal tenderness with minimal rebound and guarding. With a diagnosis of malignant ovarian tumor, an exploratory laparotomy was done and a twisted ovarian mass was found which was excised completely. Histopathological evaluation of the mass revealed massive oedema of the ovary. Massive ovarian oedema should be suspected in women at the fertile age range with solid enlargement of the ovary.

Metastasis from breast carcinoma to endometrial polyp

Metastasis of a breast carcinoma to an endometrial polyp is extremely rare, with only ten cases having been reported in the literature up to now. We present the case of a 60-year-old woman with invasive ductal carcinoma who complained of vaginal bleeding. She underwent hysteroscopy with biopsy. Microscopic examination revealed an endometrial polyp which contained foci of adenocarcinoma. The morphologic features of the tumor were identical to the original breast carcinoma.

A first insight into the genetic diversity and population structure of Mycobacterium tuberculosis in Zonguldak, Turkey

This study evaluated the molecular epidemiology and biodiversity of Mycobacterium tuberculosis isolates in Zonguldak, Turkey, and investigated the presence and significance of the LAM7-TUR clone by spoligotyping and mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) analysis. In total, 128 isolates were tested by spoligotyping; 25 selected isolates representative of the LAM7-TUR clone and similar types were also tested by MIRU-VNTR analysis. In total, 47 distinct patterns were revealed by spoligotyping, represented by 13 clusters containing between two and 28 isolates (94 isolates in total), and 34 unique patterns (a clustering rate of 73%). Using MIRU-VNTR analysis, the clustering relationships revealed by spoligotyping were confirmed. The most common spoligotyping profile was SIT53, followed by SIT41 (LAM7-TUR) and SIT50. The SIT284 clone was another phylogeographically specific clonal complex whose presence in Turkey may be endemic. The LAM7-TUR genotype was highly prevalent in Zonguldak.

A rare anatomical variation of the spinal accessory nerve

Considerable inter- and intra-individual anatomical differences can be observed during neck dissections. In this case report, we describe an unusual relationship of the accessory nerve to the internal jugular vein.

Brain MR spectroscopy findings in neonates with hypothyroidism born to mothers living in iodine-deficient areas

BACKGROUND AND PURPOSE

Iodine deficiency and hypothyroxinemia have a negative effect on the development of the central nervous system during fetal and early postnatal life. MR spectroscopy is a sensitive technique for detecting the changes of brain metabolites in various neurodevelopmental disorders. By using MR spectroscopy, we aimed to show the decrease in N-acetylaspartate (NAA) levels in neonates with hypothyroidism who were born in iodine-deficient areas and its normalization with early thyroxine therapy.

METHODS

Eight congenital hypothyroid and 8 healthy full-term neonates were chosen as study and control groups, respectively. Serum thyroid hormones and median urinary iodine concentration of the neonates and their mothers were measured. Measurements of NAA, choline (Cho), and creatine (Cr) were made in frontal white matter, parietal white matter (PWM), and the thalamus with MR spectroscopy, first at 5-7 days of life and after 8 weeks of thyroxine therapy in the study group and at the same time in the control group.

RESULTS

The patient group had significantly lower NAA/Cr ratios in PWM and the thalamus (P < .05, for each), whereas the difference between Cho/Cr ratios of the 2 groups before therapy was not significant. After 8 weeks of thyroxine therapy, measurements did not show significant difference between study and control groups.

CONCLUSION

MR spectroscopy performed in neonates with hypothyroidism reveals that intrauterine hypothyroxinemia due to iodine deficiency results in significant decrease in NAA levels in PWM and the thalamus and that the normalization of NAA levels is achieved with early thyroxine therapy.

Immunophenotypical profiles of salivary gland tumours: a new evidence for their histogenetic origin

The histogenetic origin of salivary gland tumours is not clear. In normal tissues smooth muscle actin (SMA) is expressed in myoepithelial cells, CK14 immunoreactivity is seen in myoepithelial and basal cells and CK10 in keratinized squamous epithelium. In this study, we examine the immunophenotypic properties of salivary gland tumours in order to obtain further insight into their histogenesis. 30 cases of salivary gland tumours (18 pleomorphic adenomas, 8 Warthin's tumours, 2 basal cell adenomas, 2 acinic cell carcinomas) were included in our study. Cytokeratin (CK) 10, CKI4, CKI7, CK18, CK 19, and smooth muscle actin (SMA) immunostains were applied to the sections. Immunoreactivities were detected and the statistical significance was evaluated by chi square test. SMA was not detected in Warthin's tumour (p < 0.0001). CK14 was found in all tumours except acinic cell carcinomas (p < 0.0001). CK10 immunoreactivity was observed in 5 Warthin's tumour. In conclusion, pleomorphic adenomas and basal cells adenomas originate from stem cells. Immunophenotypic profile of Warthin's tumour is suggestive of an embryological remnant origin.

Carcinoid tmour of the common bile duct: report of a case and a review of the literature

Carcinoid tumours of the common bile duct are extremely rare lesions. In this article we report a case with an extrahepatic bile duct carcinoid tumour. A 40-year-old woman suffered from biliary colic and jaundice. Pre-operative computed tomography demonstrated a tumour in the biliary tract. At laparotomy there was a tumour invading the common bile duct. Common bile duct resection was performed. Carcinoid tumour of the common bile duct was diagnosed histopathologically. For extrahepatic bile duct carcinoid tumours surgical resection is the only treatment modality that offers a chance to provide a cure and prolonged disease-free survival. The favourable histopathological and biological features of these tumours encouraged the surgeons to use more aggressive approaches for advanced disease.

Evaluation of alloderm and autologous skin in quadriceps muscles of rats for injection laryngoplasty

There are three surgical methods utilized in treating glottic insufficiency: laryngeal framework surgery, reinnervation procedures and injection medialization. The trend towards the use of less invasive procedures led us to focus on injection medialization in this study. The advantages of vocal fold injection are that the procedure requires no external incisions, is easily applicable and can be applied in an office setting. Furthermore, injection medialization is applicable in cases of atrophic vocal fold and vocal fold scarring. In developing injection medialization, laryngologists are in search of an "ideal material" that should be biocompatible and resistant to resorption. In the initial applications of this method, synthetic materials were used. In the past 2 decades, however, researchers have become more and more interested in the advantages of biological materials. In our animal study, we investigated the behavior of AlloDerm and autologous skin injected in the quadriceps muscles of rats. The materials were easily injected. Histopathological and volumetric analyses were done; the rats were sacrificed the 1st day post-injection and subsequently in the 1st, 3rd and 6th months. AlloDerm's absorption levels were generally high, and its inflammation and fibrosis levels were low and medium. In the 6th month, histiocytic foreign body reaction was observed. The mean graft yield was 4.5%. Autologous skin results for inflammation and fibrosis levels were similar to those of AlloDerm. However, no foreign body reaction was observed in AS injected muscle. The graft yield was 74.6%. The growth of keratin cysts had an effect on the results of the graft yield.