Hyperconnecitivity between dorsal attention and frontoparietal networks predicts treatment response in obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) presented with repetitive obsessions and/or compulsions were associated with disrupted resting-state functional connectivity (rs-FC). To investigate the pharmacological treatment effect on rs-FC changes in OCD patients we conducted the seed-to-voxel FC analyses using dorsal attention network (DAN), default mode network (DMN), salience network (SN) and frontoparietal network (FPN) and basal ganglia seeds. Twenty-two healthy subjects and twenty-four unmedicated OCD patients underwent resting-state functional magnetic resonance imaging. Patients were rescanned after 12 weeks of escitalopram treatment. We found increased FC both within the DAN and between the DAN and the FPN which was ameliorated after medication and correlated significantly with the clinical improvement in obsession scores. We also observed an anticorrelation between the left caudate and the supplementary motor area in unmedicated OCD patients which also normalized with treatment. Results further showed treatment related normalization of orbitofrontal cortex hyperconnectivity with DMN and hypoconnectivity with DAN whereas aberrant FC between the SN and visual areas appears to be a medication effect. We suggest that DAN to FPN hyperconnectivity which is positively correlated with clinical improvement in obsession scores at pre-treatment stage in present study has a potential for being a neuroimaging marker to predict the treatment response in OCD.

Perspectives for Using CO2 as a Feedstock for Biomanufacturing of Fuels and Chemicals

Microbial cell factories offer an eco-friendly alternative for transforming raw materials into commercially valuable products because of their reduced carbon impact compared to conventional industrial procedures. These systems often depend on lignocellulosic feedstocks, mainly pentose and hexose sugars. One major hurdle when utilizing these sugars, especially glucose, is balancing carbon allocation to satisfy energy, cofactor, and other essential component needs for cellular proliferation while maintaining a robust yield. Nearly half or more of this carbon is inevitably lost as CO2 during the biosynthesis of regular metabolic necessities. This loss lowers the production yield and compromises the benefit of reducing greenhouse gas emissions-a fundamental advantage of biomanufacturing. This review paper posits the perspectives of using CO2 from the atmosphere, industrial wastes, or the exhausted gases generated in microbial fermentation as a feedstock for biomanufacturing. Achieving the carbon-neutral or -negative goals is addressed under two main strategies. The one-step strategy uses novel metabolic pathway design and engineering approaches to directly fix the CO2 toward the synthesis of the desired products. Due to the limitation of the yield and efficiency in one-step fixation, the two-step strategy aims to integrate firstly the electrochemical conversion of the exhausted CO2 into C1/C2 products such as formate, methanol, acetate, and ethanol, and a second fermentation process to utilize the CO2-derived C1/C2 chemicals or co-utilize C5/C6 sugars and C1/C2 chemicals for product formation. The potential and challenges of using CO2 as a feedstock for future biomanufacturing of fuels and chemicals are also discussed.

Biotechnological production of omega-3 fatty acids: current status and future perspectives

Omega-3 fatty acids, including alpha-linolenic acids (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), have shown major health benefits, but the human body's inability to synthesize them has led to the necessity of dietary intake of the products. The omega-3 fatty acid market has grown significantly, with a global market from an estimated USD 2.10 billion in 2020 to a predicted nearly USD 3.61 billion in 2028. However, obtaining a sufficient supply of high-quality and stable omega-3 fatty acids can be challenging. Currently, fish oil serves as the primary source of omega-3 fatty acids in the market, but it has several drawbacks, including high cost, inconsistent product quality, and major uncertainties in its sustainability and ecological impact. Other significant sources of omega-3 fatty acids include plants and microalgae fermentation, but they face similar challenges in reducing manufacturing costs and improving product quality and sustainability. With the advances in synthetic biology, biotechnological production of omega-3 fatty acids via engineered microbial cell factories still offers the best solution to provide a more stable, sustainable, and affordable source of omega-3 fatty acids by overcoming the major issues associated with conventional sources. This review summarizes the current status, key challenges, and future perspectives for the biotechnological production of major omega-3 fatty acids.

Morphometric analysis of medial temporal lobe subregions in Alzheimer's disease using high-resolution MRI

The spread pattern of progressive degeneration seen in Alzheimer's disease (AD) to small-scale medial temporal lobe subregions is critical for early diagnosis. In this context, it was aimed to examine the morphometric changes of the hippocampal subfields, amygdala nuclei, entorhinal cortex (ERC), and parahippocampal cortex (PHC) using MRI. MRI data of patients diagnosed with 20 Alzheimer's disease dementia (ADD), 30 amnestic mild cognitive impairment (aMCI), and 30 subjective cognitive impairment (SCI) without demographic differences were used. Segmentation and parcellation were performed using FreeSurfer. The segmentation process obtained volume values of 12 hippocampal subfields and 9 amygdala nuclei. Thickness values of ERC and PHC were calculated with the parcellation process. ANCOVA was performed using age, education and gender as covariates to evaluate the intergroup differences. Linear discriminant analysis was used to investigate whether atrophy predicted groups at an early stage. ERC and PHC thickness decreased significantly throughout the disease continuum, while only ERC was affected in the early stage. When the hippocampal and amygdala subfields were compared volumetrically, significant differences were found in the amygdala between the SCI and aMCI groups. In the early period, only volume reduction in the anterior amygdaloid area of the amygdala nuclei exceeded the significance threshold. Research on AD primarily focuses on original hippocampocentric structures and their main function which is episodic memory. Our results emphasized the significance of so far relatively neglected olfactocentric structures and their functions, such as smell and social cognition in the pre-dementia stages of the AD process.

The mammalian midbody and midbody remnant are assembly sites for RNA and localized translation

Long ignored as a vestigial remnant of cytokinesis, the mammalian midbody (MB) is released post-abscission inside large extracellular vesicles called MB remnants (MBRs). Recent evidence suggests that MBRs can modulate cell proliferation and cell fate decisions. Here, we demonstrate that the MB matrix is the site of ribonucleoprotein assembly and is enriched in mRNAs that encode proteins involved in cell fate, oncogenesis, and pluripotency, which we are calling the MB granule. Both MBs and post-abscission MBRs are sites of spatiotemporally regulated translation, which is initiated when nascent daughter cells re-enter G1 and continues after extracellular release. MKLP1 and ARC are necessary for the localization and translation of RNA in the MB dark zone, whereas ESCRT-III is necessary to maintain translation levels in the MB. Our work reveals a unique translation event that occurs during abscission and within a large extracellular vesicle.

Functional and structural connectivity in the Papez circuit in different stages of Alzheimer's disease

OBJECTIVE

Alzheimer's disease (AD) is a progressive neurodegenerative continuum with memory impairment. We aimed to examine the detailed functional (FC) and structural connectivity (SC) pattern of the Papez circuit, known as the memory circuit, along the AD.

METHODS

MRI data of 15 patients diagnosed with AD dementia (ADD), 15 patients with the amnestic mild cognitive impairment (MCI), and 15 patients with subjective cognitive impairment were analyzed. The FC analyses were performed between main nodes of the Papez circuit, and the SC was quantified as fractional anisotropy (FA) of the main white matter pathways of the Papez circuit.

RESULTS

The FC between the retrosplenial (RSC) and parahippocampal cortices (PHC) was the earliest affected FC, while a manifest SC change in the ventral cingulum and fornix was observed in the later ADD stage. The RSC-PHC FC and the ventral cingulum FA efficiently predicted the memory performance of the non-demented participants.

CONCLUSIONS

Our findings revealed the importance of the Papez circuit as target regions along the AD.

SIGNIFICANCE

The ventral cingulum connecting the RSC and PHC, a critical overlap area between the Papez circuit and the default mode network, seems to be a target region associated with the earliest objective memory findings in AD.

Medulloblastoma in adults: evaluation of the Dutch society for neuro-oncology treatment protocol

PURPOSE

Medulloblastoma is a rare tumor in adults. The objective of this nationwide, multicenter study was to evaluate the toxicity and efficacy of the Dutch treatment protocol for adult medulloblastoma patients.

METHODS

Adult medulloblastoma patients diagnosed between 2010 and 2018 were identified in the Dutch rare tumors registry or nationwide pathology database. Patients with intention to treat according to the national treatment protocol were included. Risk stratification was performed based on residual disease, histological subtype and extent of disease. All patients received postoperative radiotherapy [craniospinal axis 36 Gy/fossa posterior boost 19.8 Gy (14.4 Gy in case of metastases)]. High-risk patients received additional neoadjuvant (carboplatin-etoposide), concomitant (vincristine) and adjuvant chemotherapy (carboplatin-vincristine-cyclophosphamide) as far as feasible by toxicity. Methylation profiling, and additional next-generation sequencing in case of SHH-activated medulloblastomas, were performed.

RESULTS

Forty-seven medulloblastoma patients were identified, of whom 32 were treated according to the protocol. Clinical information and tumor material was available for 28 and 20 patients, respectively. The histological variants were mainly classic (43%) and desmoplastic medulloblastoma (36%). Sixteen patients (57%) were considered standard-risk and 60% were SHH-activated medulloblastomas. Considerable treatment reductions and delays in treatment occurred due to especially hematological and neurotoxicity. Only one high-risk patient could complete all chemotherapy courses. 5-years progression-free survival (PFS) and overall survival (OS) for standard-risk patients appeared worse than for high-risk patients (PFS 69% vs. 90%, OS 81% vs. 90% respectively), although this wasn't statistically significant.

CONCLUSION

Combined chemo-radiotherapy is a toxic regimen for adult medulloblastoma patients that may result in improved survival.

Liquid crystal microcapillary-based sensors for affordable analytical applications

Stimuli-responsive properties of liquid crystals (LCs), when combined with their optical properties, offer sensitive and rapid sensing applications. Here, we propose and demonstrate a microcapillary-based method to be applied for the online detection of amphiphilic species, which can be further used for tracking biological and chemical species in aqueous media. Specifically, we used compartments (300-1400 μm) of nematic 4-cyano-4'-pentylbiphenyl (5CB) that were positioned into cylindrical glass microcapillaries that promote homeotropic anchoring. The flat surfaces of the cylindrical LC compartments were in contact with an aqueous media. We characterized the equilibrium and nonequilibrium response of LCs upon a change in their anchoring at the aqueous interfaces. Upon anchoring transition, we observed the formation of a positively charged defect at the proximity of the interface that moved to the center of the LC compartment and reached equilibrium, a four-petal configuration. This transition was observed to take an average of 41 ± 19 min., which we related to the motion of the defect due to the imbalance of the elastic forces. During the transition, we observed metastable states which could be removed via thermal treatment. We showed the capillary sensors to be useful considering their ease of additional quantification. We also show that the sensors are reversible that facilitate temporal and cumulative quantification. The findings reported in this study can further be used to develop sensors for specific purposes that require continuous tracking of the chemical and biological species that is critical for the health and safety of the individuals and society.

Altered Resting State Functional Connectivity and Its Correlation with Cognitive Functions at Ultra High Risk for Psychosis

The aim of this study is to identify robust resting state-functional connectivity (rs-FC) alterations and their correlations with the neuropsychological characteristics of Ultra-High Risk (UHR) for psychosis subjects compared to healthy controls (HCs). Twenty individuals with UHR and sixteen HCs underwent resting-state functional magnetic resonance imaging (rs-fMRI) and a cognitive battery evaluating attention, episodic memory and executive functions. Compared to HCs, UHR individuals showed working memory and set-shifting impairments. In functional connectivity (FC) analyses, the Default Mode Network (DMN) of the UHR subjects displayed increased FC with the visual areas and decreased FC with the Dorsal Attention Network (DAN). Additionally, the salience network (SN) of the UHR subjects displayed increased connectivity with wide posterior cortical areas in the temporal, parietal and occipital lobes, corresponding to posterior nodes of the SN itself, the Somato-Motor Network (SMN) and the DAN. The SN connectivity with the left SMN and DAN was positively correlated with the Trail Making Test - B scores of the UHR subjects. These findings show that the SN and DMN, which mostly show abnormal connectivity patterns in psychosis, are also affected in UHR subjects, while the SN plays a more central role with its hyperconnectivity to the DAN and SMN.

Evaluation of Resting-State Functional Magnetic Resonance Imaging Findings of Patients with Social Anxiety Disorder

OBJECTIVE

The most prominent functional magnetic resonance imaging findings about social anxiety disorder are increased activity in emotional regulation areas (amygdala, insula, hippocampus, dorsal anterior cingulate cortex) and fear circuit, and altered activity in prefrontal cortex. This study aims to investigate network abnormalities during resting state.

METHOD

Resting state functional magnetic resonance images of 21 drug-free patients with social anxiety disorder and 21 healthy controls (matched on age, gender, and years of education) were recorded. Resting state functional connectivity networks were obtained with independent component analysis, and were compared by using the voxel based t-test between the two groups.

RESULTS

Patients with social anxiety disorder displayed decreased intrinsic functional connectivity in the anterior component of the salience network (left orbitofrontal cortex) and increased intrinsic functional connectivity in the posterior component of the salience network (left supramarginal gyrus).

CONCLUSION

Most of the studies about social anxiety disorder mainly focused on fear circuit and emotional regulation areas by using anxiety provoking tasks or by using seed based analysis of functional connectivity. By applying a whole-brain independent component analysis, we found altered functional connectivity in the salience network, but no significant difference was found in the fear circuit areas. Our results suggest that abnormal connectivity in the salience network might play a crucial role in the neurobiology of social anxiety disorder.

Prognostic utility of CURB-65 and E-CURB-65 scoring systems in healthcare associated pneumonia patients: Short- and long-term mortality

Background

The aim of our study is to evaluate whether the CURB-65 or expanded-CURB-65 score can be used in healthcare-associated pneumonia (HCAP) and subgroups of HCAP patients at the same efficiency. Thirty and 90-day mortality rates of the patients and predictive values of CURB-65 and E-CURB-65 scores were compared.

Patients and Methods

This is a retrospective study of patients who presented to the Emergency Department between January 2015 and January 2016. All patient charts above 18 years of age were evaluated according to American Thoracic Society and the Infectious Diseases Society of America (ATS/IDSA) pneumonia diagnostic criteria and pneumonia diagnoses were confirmed.

Results

167 pneumonia patients (27.8%) of all pneumonia cases were grouped as HCAP and 433 (54.4%) were grouped as community-acquired pneumonia (CAP). 43% (n = 72) of HCAP patients were classified as nursing home-associated pneumonia (NHAP) and 57% (n = 95) were classified as HCAP (except NHAP) group. NHAP patients were older than the other groups. HCAP (except NHAP) group had somehow more comorbid diseases when compared with the other groups. However, the NHAP group had more unstable vital signs and confusion rates. Hospital and ICU admissions, 30-90-day mortality rates were all significantly higher in NHAP group E-CURB-65 was found to have better predictive values than CURB-65 for 30-day and 90-day mortalities overall.

Conclusion

According to our results, commonly used scoring systems, CURB 65 and E-CURB 65, are not suitable for HCAP, NHAP, and HCAP (except NHAP) patients. NHAP patients have significant worse prognosis compared with CAP and HCAP (except NHAP) in terms of admission to intensive care and 30 and 90-day mortality rates.

B-Tensor: Brain Connectome Tensor Factorization for Alzheimer's Disease

AD is the highly severe part of the dementia spectrum and impairs cognitive abilities of individuals, bringing economic, societal and psychological burdens beyond the diseased. A promising approach in AD research is the analysis of structural and functional brain connectomes, i.e., sNETs and fNETs, respectively. We propose to use tensor representation (B-tensor) of uni-modal and multi-modal brain connectomes to define a low-dimensional space via tensor factorization. We show on a cohort of 47 subjects, spanning the spectrum of dementia, that diagnosis with an accuracy of 77% to 100% is achievable in a 5D connectome space using different structural and functional connectome constructions in a uni-modal and multi-modal fashion. We further show that multi-modal tensor factorization improves the results suggesting complementary information in structure and function. A neurological assessment of the connectivity patterns identified largely agrees with prior knowledge, yet also suggests new associations that may play a role in the disease progress.

The evaluation of myocardial performance index in patients with COVID-19: An echocardiographic follow-up study

Funding Acknowledgements

Type of funding sources: None.

Introduction

The epidemic of pneumonia caused by a new coronavirus rapidly spread all over the world. World Health Organization called the condition as coronavirus disease 2019 (COVID-19). COVID-19 has become a life-threatening public health emergency internationally. COVID-19 mostly presents by respiratory tract symptoms including fever, dry cough, and dyspnea. The disease progression causes pneumonia and acute respiratory distress syndrome. Pathophisyology of cardiovascular effects of COVID-19 have not been well known yet. Myocardial dysfunction may occur in cytokine-originated immune reactions. Myocardial performance index (MPI) is a feasible parameter that reflects systolic and diastolic cardiac functions.

Purpose

We aimed to evaluate the MPI in patients with COVID-19.

Methods

The study consisted of 40 patients diagnosed with COVID-19 who had mild pneumonia and had not needed intensive care treatment. Transthoracic echocardiographic examination was performed in all patients at the acute stage of infection and after clinical recovery. The average time interval between the baseline and recovery echocardiography exam was about 28 ± 3,4 days. Blood samples were studied on day 0 and on days 7, 14, 21, and 28.  Immunofluorescence assay was used for COVID-19 antibody titers.  Respiratory secretions were sent for RT-PCR tests.

Results

The mean age was 54 ± 11 years ( male 26 (65% ) ). Statistically significant higher MPI (0.56 ± 0.09 versus 0.44 ± 0.07, p < 0.001), longer isovolumic relaxation time (112.3 ± 13.4 versus 91.8 ± 12.1ms, p < 0.001), longer deceleration time (182.1 ± 30.6 versus 161.5 ± 43.5ms, p = 0.003), shorter ejection time (279.6 ± 20.3 versus 298.8 ± 36.8ms, p < 0.001) and higher E/A ratio (1.53 ± 0.7 versus  1.22 ± 0.4, p < 0.001), were observed during acute period of  infection compared to ones after clinical recovery. Compared with basal values, no significant change in left ventricular systolic ejection fraction was observed after clinical recovery (60.3± 3.2% versus 61.7 ± 2.4%, p > 0.05). Isovolumic contraction time was similar at acute infection and after clinical recovery ( 44.3 ± 7.8 versus 40.6 ± 9.7ms, p > 0.05)

Conclusion

In conclusion, our study suggests global reversible LV dysfunction in COVID-19 patients with preserved LV systolic function based on tissue Doppler derived MPI. This could be due to isolated subclinical diastolic dysfunction. To our knowledge, this study is the first echocardiographic follow-up study that evaluated the systolic and diastolic function of the left ventricle in COVID -19 patients. The underlying mechanism and its clinical significance can be established by further studies.

Functional connectivity disturbances of ascending reticular activating system and posterior thalamus in juvenile myoclonic epilepsy in relation with photosensitivity: A resting-state fMRI study

OBJECTIVE

Juvenile myoclonic epilepsy (JME) is typified by the occurrence of myoclonic seizures after awakening, though another common trait is myoclonic seizures triggered by photic stimulation. We aimed to investigate the functional connectivity (FC) of nuclei in the ascending reticular activating system (ARAS), thalamus and visual cortex in JME with and without photosensitivity.

METHODS

We examined 29 patients with JME (16 photosensitive (PS), 13 non- photosensitive-(NPS)) and 28 healthy controls (HCs) using resting-state functional magnetic resonance imaging (rs-fMRI). Seed-to-voxel FC analyses were performed using 25 seeds, including the thalamus, visual cortex, and ARAS nuclei.

RESULTS

Mesencephalic reticular formation seed revealed significant hyperconnectivity between the bilateral paracingulate gyrus and anterior cingulate cortex in JME group, and in both JME-PS and JME-NPS subgroups compared to HCs (p_FWE-corr < 0.001; p_FWE-_corr < 0.001; p_FWE-_corr = 0.002, respectively). Locus coeruleus seed displayed significant hyperconnectivity with the bilateral lingual gyri, intracalcarine cortices, occipital poles and left occipital fusiform gyrus in JME-PS group compared to HCs (p_FWE-corr <0.001). Additionally, locus coeruleus seed showed significant hyperconnectivity in JME-PS group compared to JME-NPS group with a cluster corresponding to the bilateral lingual gyri and right intracalcarine cortex (p_FWE-corr < 0.001). Lastly, the right posterior nuclei of thalamus revealed significant hyperconnectivity with the right superior lateral occipital cortex in JME-PS group compared to HCs (p_FWE-corr < 0.002).

CONCLUSIONS

In JME, altered functional connectivity of the arousal networks might contribute to the understanding of myoclonia after awakening, whereas increased connectivity of posterior thalamus might explain photosensitivity.

Functional Connectivity Analysis in Heterozygous Glucocerebrosidase Mutation Carriers

BACKGROUND

There is evidence that alterations in functional connectivity (FC) of the striatocortical circuits may appear before the onset of clinical symptoms of Parkinson's disease (PD).

OBJECTIVE

The aim of this study was to investigate FC of the striatocortical circuitry in asymptomatic carriers of heterozygous glucocerebrosidase (GBA) mutations, which pose a significant risk for developing PD.

METHODS

Twenty-one parents of confirmed Gaucher disease patients who were carrying heterozygous GBA mutations and 18 healthy individuals matched for age and gender were included. GBA mutation analysis was performed in all participants. Clinical evaluation included neurological examination, Mini Mental State Examination, and UPDRS Part III. Structural and functional MRI data of 18 asymptomatic GBA mutation carriers (asGBAmc) and 17 healthy controls (HC) were available. FC was analyzed with seed-based approach.

RESULTS

Eleven asymptomatic mutation carriers had heterozygous p.L483P mutation, 6 subjects heterozygous p.N409S mutation and 1 subject heterozygous p.R392G mutation in GBA gene. Mini-Mental State Examination mean score was 28.77 (±1.16) and 29.64 (±0.70) in asGBAmc and HC groups, respectively (p = 0.012). Significant increased connectivityConclusion:Our results suggest that alterations in striatocortical FC can be detected in asymptomatic heterozygous GBA mutation carriers who are at risk of developing PD. These findings may provide insight into network changes during the asymptomatic phase of PD.

Functional neural substrates of football fanaticism: Different pattern of brain responses and connectivity in fanatics

AIM

Sports activities provide social interaction for humans. Commitment to a given team is a salient feature of being a sports fan and becomes a prominent part of self-identification for fanatics. Emotion, subjective hedonic experience, and non-romantic love are related to fan behaviors. Few studies have evaluated the neural basis of sports fanaticism.

METHODS

Thirty men, including 16 football fanatics and 14 non-fanatics, with a mean age of 27.4 ± 6.4 years (range, 20-48 years) were enrolled. Subjects underwent functional MRI while watching a set of goals scored by favorite, rival, and neutral teams.

RESULTS

The analysis of variance in a general linear model revealed a significant Group × Condition interaction effect in the bilateral dorsal anterior cingulate cortex (dACC) that was more prominent in the left hemisphere. In the post-hoc comparisons, fanatics showed increased activation in bilateral dACC, supplementary motor area, superior frontal cortex, right dorsolateral prefrontal cortex, and right insula for Favorite > Neutral contrast and an increased activation in bilateral dACC and supplementary motor area for Rival > Neutral contrast. Seed-based connectivity analyses using the areas with significant activation differences revealed increased connectivity between dACC and several regions, including the left posterior lateral temporal area, insula, bilateral medial temporal area, and medial superior frontal area as well as the basal ganglia in fanatics compared to non-fanatics.

CONCLUSION

Our results suggest that football fanatics exhibit a different brain activation and connectivity pattern from non-fanatics, both under favorable and unfavorable conditions. This brain activity and connectivity pattern under emotionally laden conditions may represent higher responses to rewards, higher emotional valence attribution, and stronger motivational state of football fanatics, which might underlie their unusual behavioral responses.

White-matter changes in early and late stages of mild cognitive impairment

Mild Cognitive Impairment (MCI) is characterized by cognitive deficits that exceed age-related decline, but not interfering with daily living activities. Amnestic type of the disorder (aMCI) is known to have a high risk to progress to Alzheimer's Disease (AD), the most common type of dementia. Identification of very early structural changes in the brain related to the cognitive decline in MCI patients would further contribute to the understanding of the dementias. In the current study, we target to investigate whether the white-matter changes are related to structural changes, as well as the cognitive performance of MCI patients. Forty-nine MCI patients were classified as Early MCI (E-MCI, n = 24) and Late MCI (L-MCI, n = 25) due to their performance on The Free and Cued Selective Reminding Test (FCSRT). Age-Related White-Matter Changes (ARWMC) scale was used to evaluate the white-matter changes in the brain. Volumes of specific brain regions were calculated with the FreeSurfer program. Both group and correlation analyses were conducted to show if there was any association between white-matter hyperintensities (WMHs) and structural changes and cognitive performance. Our results indicate that, L-MCI patients had significantly more WMHs not in all but only in the frontal regions compared to E-MCI patients. Besides, ARWMC scores were not correlated with total hippocampal and white-matter volumes. It can be concluded that WMHs play an important role in MCI and cognitive functions are affected by white-matter changes of MCI patients, especially in the frontal regions.

Measurement of cognitive dynamics during video watching through event-related potentials (ERPs) and oscillations (EROs)

Event-related potentials (ERPs) and oscillations (EROs) are reliable measures of cognition, but they require time-locked electroencephalographic (EEG) data to repetitive triggers that are not available in continuous sensory input streams. However, such real-life-like stimulation by videos or virtual-reality environments may serve as powerful means of creating specific cognitive or affective states and help to investigate dysfunctions in psychiatric and neurological disorders more efficiently. This study aims to develop a method to generate ERPs and EROs during watching videos. Repeated luminance changes were introduced on short video segments, while EEGs of 10 subjects were recorded. The ERP/EROs time-locked to these distortions were analyzed in time and time-frequency domains and tested for their cognitive significance through a long term memory test that included frames from the watched videos. For each subject, ERPs and EROs corresponding to video segments of recalled images with 25% shortest and 25% longest reaction times were compared. ERPs produced by transient luminance changes displayed statistically significant fluctuations both in time and time-frequency domains. Statistical analyses showed that a positivity around 450 ms, a negativity around 500 ms and delta and theta EROs correlated with memory performance. Few studies mixed video streams with simultaneous ERP/ERO experiments with discrete task-relevant or passively presented auditory or somatosensory stimuli, while the present study, by obtaining ERPs and EROs to task-irrelevant events in the same sensory modality as that of the continuous sensory input, produces minimal interference with the main focus of attention on the video stream.

Identification of the pedunculopontine nucleus and surrounding white matter tracts on 7T diffusion tensor imaging, combined with histological validation

BACKGROUND

The pedunculopontine nucleus (PPN) has been studied as a possible target for deep brain stimulation (DBS) for Parkinson's disease (PD). However, identifying the PPN can be challenging as the PPN is poorly visualized on conventional or even high-resolution MR scans. From histological studies it is known that the PPN is surrounded by major white matter tracts, which could function as possible anatomical landmarks.

METHODS

This study aimed to localize the PPN using 7T magnetic resonance (MR) imaging and diffusion tensor imaging (DTI) of its white matter borders in one post-mortem brain. Histological validation of the same specimen was performed. The PPN was segmented in both spaces, after which the two masks were compared using the Dice Similarity Index (DSI). The DSI compared the similarity of two samples on an inter-individual level and validated the MR findings. The error in distance between the center of the two 3D segmentations was measured by use of the Euclidean distance.

RESULTS

The PPN can be found in between the superior cerebellar peduncle and the medial lemniscus on both the FA-maps of the DTI images and the histological sections. The histological transverse sections showed to be superior to recognize the PPN (DSI: 1.0). The DTI images have a DSI of 0.82. The overlap-masks of both spaces showed a DSI of 0.32, whereas the concatenation-masks of both spaces showed a remarkable overlap, a DSI of 0.94. Euclidean distance of the overlap- and concatenation-mask in the two spaces showed to be 1.29 mm and 1.59 mm, respectively.

CONCLUSION

This study supports previous findings that the PPN can be identified using FA-maps of DTI images. For possible clinical application in DBS localization, in vivo validation of the findings of our study is needed.

The Efficacy of 2.5% Phenylephrine and Flurbiprofen Combined in Inducing and Maintaining Pupillary Dilatation during Cataract Surgery

Purpose

To evaluate the effectiveness of phenylephrine 2.5% and flurbiprofen 0.03% combined in inducing and maintaining mydriasis during extracapsular cataract extraction (ECCE).

Methods

One hundred patients undergoing ECCE + intraocular lens (IOL) implantation were randomly divided into four groups. The first group was given phenylphrine 10%, the second group phenylephrine 10% + flurbiprofen, the third group phenylephrine 2.5% and fourth group phenylephrine 2.5% + flurbiprofen. Cyclopentolate 1% was used in all patients. Phenylephrine and cyclopentolate were instilled preoperatively four times during 1 hour and flurbiprofen was given four times the day before surgery and twice with an hour's interval before operation. Pre-operative and post-cortex aspiration horizontal pupil diameters were measured with callipers viewed through the operating microscope.

Results

Pupil diameters in pre-operative and post-cortex aspiration were no different in the 2.5% and 10% phenylephrine groups (p>0.05). Both diameters were larger and pupillary constriction was smaller in the flurbiprofen groups (p<0.05).

Conclusions

2.5% phenylephrine was as effective as 10% phenylephrine, with and without flurbiprofen, in inducing and maintaining pupil dilatation during ECCE surgery.

General practitioners' approach to malingering in basic military training centres

OBJECTIVES

Malingering can be defined as the abuse of the right to benefit from the health services. In this study, the frequency of the malingering cases in Basic Military Training Centres (BMTCs) and the behaviours and the attitudes of the military physicians towards the recruits who are suspected malingerers were described.

METHOD

A total of 17 general practitioners in nine different BMTCs in different regions of Turkey constitute the universe of this descriptive study. In the questionnaire, there were a total of 30 questions about the descriptive characteristics of the participants and their attitudes and behaviours towards malingering. Informed consent form and a questionnaire were applied through the intranet via participants' emails. In the study, 15 physicians were reached with a response rate of 88.2%.

RESULTS

All of the physicians suspected malingering in some of the soldiers who were examined. A total of 80% of the physicians (n=12) suspected malingering in at least 10% of the patients they examined. Only 13.3% of the physicians (n=2) had officially diagnosed a case of malingering in the last training period. All of the participants stated that they did not report the official decision for every soldier suspected of malingering. Instead of reporting official decision for malingering, the military physicians apply alternative procedures for suspected malingerers.

CONCLUSIONS

In countries where the military service is compulsory, prevalence of malingering is estimated to be higher (approximately 5-25%). The problem of malingering is often underestimated due to the fact it is usually overlooked. Malingering remains a problem for the entire military healthcare system, due to the difficulties in exact diagnosis. Therefore, it can be useful to take some practical administrative measures for the soldiers who are prone to malingering, in order to discourage the behaviour.

FT-IR spectroscopy and multivariate analysis as an auxiliary tool for diagnosis of mental disorders: Bipolar and schizophrenia cases

In this study, a methodology based on Fourier-transform infrared spectroscopy and principal component analysis and partial least square methods is proposed for the analysis of blood plasma samples in order to identify spectral changes correlated with some biomarkers associated with schizophrenia and bipolarity. Our main goal was to use the spectral information for the calibration of statistical models to discriminate and classify blood plasma samples belonging to bipolar and schizophrenic patients. IR spectra of 30 samples of blood plasma obtained from each, bipolar and schizophrenic patients and healthy control group were collected. The results obtained from principal component analysis (PCA) show a clear discrimination between the bipolar (BP), schizophrenic (SZ) and control group' (CG) blood samples that also give possibility to identify three main regions that show the major differences correlated with both mental disorders (biomarkers). Furthermore, a model for the classification of the blood samples was calibrated using partial least square discriminant analysis (PLS-DA), allowing the correct classification of BP, SZ and CG samples. The results obtained applying this methodology suggest that it can be used as a complimentary diagnostic tool for the detection and discrimination of these mental diseases.

A novel missense mutation (N78D) in a family with von Hippel-Lindau disease with central nervous system haemangioblastomas, pancreatic and renal cysts

von Hippel-Lindau (VHL) disease is a hereditary tumor syndrome caused by mutations in the VHL tumor suppressor gene. In a family with VHL, we identified a novel missense mutation (N78D), which affects a fully conserved residue in the VHL protein. Interestingly, several other missense mutations reported at same codon in the VHL protein that might be associated with a low risk of renal cell carcinoma (RCC) but not pheochromocytoma appear to be associated with a VHL type 1 phenotype. At the moment, RCC is present in none of the affected mutation carriers in the family described here. In contrast to other missense changes at codon 78, the change in our VHL family is predicted to have a mild effect on VHL function, which apparently is insufficient to cause predisposition to RCC. Our findings suggest that the risk of RCC in VHL is attributable to the severity of the amino acid substitution at this particular codon in the VHL protein.

Prognostic significance of estrogen receptor, progesterone receptor, HER2/neu, Ki-67, and nm23 expression in patients with invasive breast cancer

PURPOSE

To determine the prognostic significance of estrogen receptor (ER), progesterone receptor (PR), HER2/neu, Ki-67, and nm23 immunohistochemical expression with respect to progression free survival (PFS) and overall survival (OS) in Turkish patients with invasive breast cancer (IBC).

METHODS

Patients with IBC (n = 81; mean age = 51.9 ± 11.1 years) were prospectively enrolled at the Department of Oncology, Uludag University Medical Center, Bursa, Turkey. Immunohistochemistry was performed on formalin- fixed, paraffin-embedded tissue sections.

RESULTS

We did not find any significant association between immunohistochemical expression of ER, PR, HER2/ neu, Ki-67, and nm23 and the baseline characteristics of IBC patients. The median patient PFS was 30 months (range 22-45), and the median OS was 32 months (range 23-46). Stratification of the patient population according to nm23 immunohistochemical expression revealed a statistically significant difference in terms of both OS (p < 0.05) and DFS (p < 0.05). Multivariate Cox regression analysis indicated that tumor grade, axillary lymph node status, and nm23 immunohistochemical expression were the 3 main independent prognostic factors for PFS and OS in IBC patients.

CONCLUSION

Reduced nm23 immunohistochemical expression is an independent negative prognostic factor for OS and PFS. Patients with negative nm23 expression may require a more intensive follow-up.

A multi-institutional evaluation of carboplatin plus docetaxel regimen in elderly patients with advanced gastric cancer

PURPOSE

Albeit the majority of gastric cancers occur at advanced age, little is known regarding the optimal systemic treatment of elderly patients with advanced gastric cancer (AGC).

METHODS

Patients with AGC who were ≥ 65 years old and were treated with carboplatin (area under the curve/AUC 5,on day 1, every 3 weeks) plus docetaxel (75 mg/m(2), on day 1, every 3 weeks) at 3 institutions were included in this retrospective analysis. The efficacy and the safety data of the regimen were analyzed.

RESULTS

A total of 30 patients were enrolled. They received 128 cycles of chemotherapy, with a median of 4 cycles (range 2-8). Complete response (CR) and partial response (PR) were observed in 2 (6.7%) and 10 patients (33.3%), respectively, amounting to an overall objective response rate (ORR) of 40%. Seven patients (23.3%) had disease stabilization (SD), and 11 (36.7%) showed disease progression (PD). The most common grade 3-4 toxicity was neutropenia occurring in 19 patients (63.3%). The mean progression-free survival (PFS) was 6.0 ± 0.5 months (95% CI: 5.0-7.4), and the mean overall survival (OS) 12.0 ± 1.0 months (95% CI: 9.2-12.1).

CONCLUSION

Carboplatin plus docetaxel seems to be an active and well-tolerated regimen, representing a valuable alternative to cisplatin- and/or fluoropyrimidine-containing regimens for the treatment of elderly patients with AGC.

The association of month of birth with atopy in adult patients with asthma and rhinitis in Anatolia, Turkey

BACKGROUND

Exposure to allergens in early life may predispose subjects to develop allergies and diseases related to allergic sensitisation.

OBJECTIVE

To determine the association between month of birth and atopic sensitisation in adult Turkish patients with rhinitis and/or asthma using the diagnostic method of skin prick tests.

METHODS

This prospective cross-sectional study included all adult patients who underwent skin prick testing with rhinitis and asthma from November 2009 to June 2010. Sensitisation was categorised as any sensitisation, pollen sensitisation, and house dust mite sensitisation. Multivariate logistic regression model was employed with the primary predictor being month of birth. Diagnosis (asthma, rhinitis and both), age, gender and family history of atopy were considered as potential confounders in the model. The associations were presented with both unadjusted and adjusted odds ratios (OR) and their 95% confidence interval (CI).

RESULTS

A total of 616 subjects were evaluated. Three-hundred and forty-one subjects had sensitisation to allergens according to skin prick tests. Analyses showed that subjects born in September were less likely to have documented skin test positively with pollen sensitisation [0.27 (0.09-0.84), p=0.023].

CONCLUSION

The results support the hypothesis that being born at the end of the pollen season may protect subjects from pollen sensitisation.

Identification of prognostic factors in patients with metastatic gastrointestinal stromal tumors

PURPOSE

Gastrointestinal stromal tumors (GISTs) have a complex biology which is reflected by a marked clinical heterogeneity. Thus, there has been great interest in identifying prognostic factors influencing tumor recurrence and survival. The aim of this study was to identify potential clinical and immunohistochemical prognostic factors that may affect survival and treatment outcomes in patients with metastatic GISTs.

METHODS

Between 2000 and September 2011, a total of 41 patients with metastatic GISTs (29 males and 12 females; mean age: 57.4±11.8 years; range 29-74) were referred to the Department of Oncology, Uludag University Medical School. Survival analysis for a number of potential prognostic factors was made with the main outcome results of progression-free survival (PFS) and overall survival (OS7rpar;.

RESULTS

The most common sites of isolated metastases comprised the liver (n=18), followed by lymph nodes (n=5), the omentum (n=1), and the mesothelium (n=1). The remaining patients had metastases at multiple sites. Cox regression analysis identified ileal location as the only significant predictor of poor PFS both after first-line (p=0.023) and second-line therapy (p=0.016). Tumor location in the ileum (p=0.025) and S100 immunoreactivity (p=0.041) were both independent predictors of OS.

CONCLUSION

Tumor site and S100 positivity were the main significant independent predictors of clinical outcomes in patients with metastatic GISTs treated by standard of care.

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.

The Efficacy of Ultrasound-Guided Transversus Abdominis Plane Block in Patients Undergoing Hysterectomy

The study objective of this prospective, double-blind randomised controlled study was to evaluate the efficacy of ultrasound guided transversus abdominis plane (TAP) block and bupivacaine infiltration of the skin and subcutaneous tissue of the wound in patients undergoing hysterectomy. Patients were randomly allocated to three groups: a control group (n=18) and TAP block group (n=18) received bilateral TAP blocks with saline and bupivacaine respectively, and an infiltration group (n=19) received skin and subcutaneous wound tissue infiltration with bupivacaine at the end of surgery. After surgery patients received patient-controlled intravenous tramadol and were assessed for pain and tramadol consumption at 1, 2, 4, 6 and 24 hours.

Both the TAP and infiltration groups had lower movement and rest pain scores than the control group, with lower scores in the TAP group than the infiltration group at 6 and 24 hours. Total tramadol consumption was significantly lower in the TAP group than in the other groups at all time points. We concluded that ultrasound-guided TAP block reduced rest and movement pain after total abdominal hysterectomy and was more effective than superficial wound infiltration for postoperative pain management.

A novel biosensor based on glucose oxidase for activity determination of α - amylase

A glucose oxidase-based biosensor was developed for the determination of α-amylase activity. The determination method is based on monitoring the decrease in dissolved oxygen concentration related to the starch concentration, for which starch gives a reaction with α-amylase. Optimization parameters, including glucose oxidase amount, gelatin amount, and glutaraldehyde percentage for cross-linking, were investigated. The effects of pH, buffer system, and temperature on the biosensor system were also investigated. The biosensor had a linear relation to α-amylase activity and good measurement correlation between 0.66 and 9.83 U/ml. In sample analysis studies, α-amylase activity in baker's yeast was determined by the biosensor.

Periodontal health and treatment needs among hospitalized chronic psychiatric patients in Istanbul, Turkey

OBJECTIVE

The aim of the study was to evaluate the periodontal health and treatment needs of chronically hospitalized psychiatric patients in Istanbul, Turkey.

METHOD

The subjects' periodontal health was recorded by the CPI (Community Periodontal Index) method.

RESULTS

Of the 330 patients examined, 179 (52.5%) were males and 151 (47.5%) females. The mean age of the patients was 49.2 +/- 11.7 years. The majority (61.8%) was diagnosed with schizophrenia and 30.6% diagnosed with mental retardation. The mean length of hospitalization was 16.0 +/- 10.9 years. Healthy periodontal tissues (CPI 0) were found in 8.8% of the subjects. Bleeding on probing (CPI 1) was recorded in 6.3%, and dental calculus (CPI 2) in 51.8% of the subjects. These were determined as the worst findings. Altogether, 33% of the subjects had deep periodontal pockets, 14.2% with at least one 4- to 5-mm pocket (CPI 3), and 18.8% with at least one 6-mm pocket (CPI 4). The stepwise logistic regression analysis, between the final CPI score and seven variables including age, gender, psychiatric diagnosis, length of hospitalization, degree of helplessness, tooth brushing habits and smoking, showed that irregular tooth brushing habits and male gender were significant contributors to having a final CPI score of 2 or more. The regression analysis also showed that tooth brushing habits remained as an explanatory variable in CPI 0 coded subjects; helplessness and psychiatric diagnosis (mental retardation) in CPI 2; tooth brushing habits and psychiatric diagnosis (schizophrenia) in CPI 3; and only helplessness in CPI 4.

CONCLUSION

The present study underlines a considerable need for prevention and treatment of periodontal disease among chronic psychiatric patients in Istanbul. Efforts need to be focused above all on raising this population's awareness of the importance of oral hygiene and on early diagnosis of periodontal problems.

Oral health and treatment needs of institutionalized chronic psychiatric patients in Istanbul, Turkey

OBJECTIVE

To assess the oral health status and treatment needs in a group of hospitalized chronic psychiatric patients.

METHOD

The dental status was assessed using the DMFT index. Demographic and medical data were retrieved from the institutional clinical files.

RESULTS

491 patients were examined in the study. 258 (52.5%) of the patients were males. The mean age was 52.3 +/- 12.3 years and the average length of hospitalization was 17.5 years. The majority of the patients (69%) were diagnosed with schizophrenia. The mean DMFT was 19.25 +/- 7.85. Missing teeth (81.4%) comprised the largest proportion of the DMFT while filled teeth (0.5%) the smallest. 18.1% of the DMFT consisted of decayed teeth. Stepwise logistic regression analysis showed that the DMFT significantly increased with age (p < 0.001) and was significantly higher in schizophrenia patients than those with mental retardation (p < 0.01). Males had significantly higher decayed teeth (p < 0.01) and fewer missing teeth (p < 0.01) than females. 58 dentate subjects (14.4%) were caries free. Two hundred and thirty five patients (58.5%) required restorative care, the mean number of treatments required per patient was 1.42 +/- 1.82. Eighty-nine subjects (18.1%) were found to be completely edentulous with only 17 wearing complete dentures. 70.6% of dentate patients needed tooth extraction for caries and 36.1% for periodontal disease.

CONCLUSION

The findings of this study demonstrate poor oral health status with extensive unmet dental and prosthetic needs. These underline the urgent need for specific preventive oral health programme to improve the dental care of these chronic psychiatric inpatients.