Dynamic functional connectivity analysis reveals transient states of dysconnectivity in schizophrenia

Schizophrenia is a psychotic disorder characterized by functional dysconnectivity or abnormal integration between distant brain regions. Recent functional imaging studies have implicated large-scale thalamo-cortical connectivity as being disrupted in patients. However, observed connectivity differences in schizophrenia have been inconsistent between studies, with reports of hyperconnectivity and hypoconnectivity between the same brain regions. Using resting state eyes-closed functional imaging and independent component analysis on a multi-site data that included 151 schizophrenia patients and 163 age- and gender matched healthy controls, we decomposed the functional brain data into 100 components and identified 47 as functionally relevant intrinsic connectivity networks. We subsequently evaluated group differences in functional network connectivity, both in a static sense, computed as the pairwise Pearson correlations between the full network time courses (5.4 minutes in length), and a dynamic sense, computed using sliding windows (44 s in length) and k-means clustering to characterize five discrete functional connectivity states. Static connectivity analysis revealed that compared to healthy controls, patients show significantly stronger connectivity, i.e., hyperconnectivity, between the thalamus and sensory networks (auditory, motor and visual), as well as reduced connectivity (hypoconnectivity) between sensory networks from all modalities. Dynamic analysis suggests that (1), on average, schizophrenia patients spend much less time than healthy controls in states typified by strong, large-scale connectivity, and (2), that abnormal connectivity patterns are more pronounced during these connectivity states. In particular, states exhibiting cortical–subcortical antagonism (anti-correlations) and strong positive connectivity between sensory networks are those that show the group differences of thalamic hyperconnectivity and sensory hypoconnectivity. Group differences are weak or absent during other connectivity states. Dynamic analysis also revealed hypoconnectivity between the putamen and sensory networks during the same states of thalamic hyperconnectivity; notably, this finding cannot be observed in the static connectivity analysis. Finally, in post-hoc analyses we observed that the relationships between sub-cortical low frequency power and connectivity with sensory networks is altered in patients, suggesting different functional interactions between sub-cortical nuclei and sensorimotor cortex during specific connectivity states. While important differences between patients with schizophrenia and healthy controls have been identified, one should interpret the results with caution given the history of medication in patients. Taken together, our results support and expand current knowledge regarding dysconnectivity in schizophrenia, and strongly advocate the use of dynamic analyses to better account for and understand functional connectivity differences.

•

Studied both static and dynamic connectivity changes in schizophrenia during rest

•

Small but significant connectivity differences might be obscured in static analysis.

•

Patients show significant differences in dwell times in multiple states.

•

Disrupted thalamo-cortical connectivity in schizophrenia in a state-specific manner

Subcortical brain volume abnormalities in 2028 individuals with schizophrenia and 2540 healthy controls via the ENIGMA consortium

The profile of brain structural abnormalities in schizophrenia is still not fully understood, despite decades of research using brain scans. To validate a prospective meta-analysis approach to analyzing multicenter neuroimaging data, we analyzed brain MRI scans from 2028 schizophrenia patients and 2540 healthy controls, assessed with standardized methods at 15 centers worldwide. We identified subcortical brain volumes that differentiated patients from controls, and ranked them according to their effect sizes. Compared with healthy controls, patients with schizophrenia had smaller hippocampus (Cohen's d=-0.46), amygdala (d=-0.31), thalamus (d=-0.31), accumbens (d=-0.25) and intracranial volumes (d=-0.12), as well as larger pallidum (d=0.21) and lateral ventricle volumes (d=0.37). Putamen and pallidum volume augmentations were positively associated with duration of illness and hippocampal deficits scaled with the proportion of unmedicated patients. Worldwide cooperative analyses of brain imaging data support a profile of subcortical abnormalities in schizophrenia, which is consistent with that based on traditional meta-analytic approaches. This first ENIGMA Schizophrenia Working Group study validates that collaborative data analyses can readily be used across brain phenotypes and disorders and encourages analysis and data sharing efforts to further our understanding of severe mental illness.

Widespread white matter microstructural differences in schizophrenia across 4322 individuals: results from the ENIGMA Schizophrenia DTI Working Group

The regional distribution of white matter (WM) abnormalities in schizophrenia remains poorly understood, and reported disease effects on the brain vary widely between studies. In an effort to identify commonalities across studies, we perform what we believe is the first ever large-scale coordinated study of WM microstructural differences in schizophrenia. Our analysis consisted of 2359 healthy controls and 1963 schizophrenia patients from 29 independent international studies; we harmonized the processing and statistical analyses of diffusion tensor imaging (DTI) data across sites and meta-analyzed effects across studies. Significant reductions in fractional anisotropy (FA) in schizophrenia patients were widespread, and detected in 20 of 25 regions of interest within a WM skeleton representing all major WM fasciculi. Effect sizes varied by region, peaking at (d=0.42) for the entire WM skeleton, driven more by peripheral areas as opposed to the core WM where regions of interest were defined. The anterior corona radiata (d=0.40) and corpus callosum (d=0.39), specifically its body (d=0.39) and genu (d=0.37), showed greatest effects. Significant decreases, to lesser degrees, were observed in almost all regions analyzed. Larger effect sizes were observed for FA than diffusivity measures; significantly higher mean and radial diffusivity was observed for schizophrenia patients compared with controls. No significant effects of age at onset of schizophrenia or medication dosage were detected. As the largest coordinated analysis of WM differences in a psychiatric disorder to date, the present study provides a robust profile of widespread WM abnormalities in schizophrenia patients worldwide. Interactive three-dimensional visualization of the results is available at www.enigma-viewer.org.

The PRIME North America randomized double-blind clinical trial of olanzapine versus placebo in patients at risk of being prodromally symptomatic for psychosis. II. Baseline characteristics of the "prodromal" sample

The first double-blind placebo-controlled clinical trial of an atypical neuroleptic medication is being conducted in symptomatic treatment-seeking patients meeting new diagnostic criteria for a putative prodromal syndrome. This identifies them as being at high risk for developing psychosis in the near future. The study aims include prevention of psychosis onset and disability, as well as palliation of ongoing symptomatology. The purpose of this report is to describe the study's "prodromally symptomatic" sample at baseline, i.e., at intake immediately prior to randomization and prior to receiving study medication. Sixty treatment-seeking patients meeting prodromal inclusion criteria were recruited across four sites: New Haven, CT (n=39), Toronto, Ontario (n=9), Calgary, Alberta (n=6), and Chapel Hill, NC (n=6). The sample was young (median age 16), largely male (65%), and came from families with high titers of serious mental illness (44%). Most patients (93%) met criteria for the Attenuated Positive Symptom (APS) prodromal syndrome and presented with significant but nonpsychotic suspiciousness, perceptual aberrations, unusual thought content, and conceptual disorganization. They presented with minimal to mild affective symptoms and substance use/abuse, but they were quite functionally compromised (mean Global Assessment of Functioning (GAF) score=42). The prodromal sample was compared with other clinical-trial samples of adolescent depression, adolescent mania, and first episode schizophrenia. Prodromal patients proved not to be depressed or manic. They were less severely ill than untreated first episode schizophrenia but more severely ill than treated first episode schizophrenia. While not psychotically disabled, these patients nevertheless present with a clinical syndrome. Subsequent reports will detail the effects of drug versus placebo on prodromal symptoms, neuropsychological profile, and the rate of conversion to psychosis.

Resting-state thalamic dysconnectivity in schizophrenia and relationships with symptoms

BACKGROUND

Schizophrenia (SZ) is a severe neuropsychiatric disorder associated with disrupted connectivity within the thalamic-cortico-cerebellar network. Resting-state functional connectivity studies have reported thalamic hypoconnectivity with the cerebellum and prefrontal cortex as well as thalamic hyperconnectivity with sensory cortical regions in SZ patients compared with healthy comparison participants (HCs). However, fundamental questions remain regarding the clinical significance of these connectivity abnormalities.

METHOD

Resting state seed-based functional connectivity was used to investigate thalamus to whole brain connectivity using multi-site data including 183 SZ patients and 178 matched HCs. Statistical significance was based on a voxel-level FWE-corrected height threshold of p < 0.001. The relationships between positive and negative symptoms of SZ and regions of the brain demonstrating group differences in thalamic connectivity were examined.

RESULTS

HC and SZ participants both demonstrated widespread positive connectivity between the thalamus and cortical regions. Compared with HCs, SZ patients had reduced thalamic connectivity with bilateral cerebellum and anterior cingulate cortex. In contrast, SZ patients had greater thalamic connectivity with multiple sensory-motor regions, including bilateral pre- and post-central gyrus, middle/inferior occipital gyrus, and middle/superior temporal gyrus. Thalamus to middle temporal gyrus connectivity was positively correlated with hallucinations and delusions, while thalamus to cerebellar connectivity was negatively correlated with delusions and bizarre behavior.

CONCLUSIONS

Thalamic hyperconnectivity with sensory regions and hypoconnectivity with cerebellar regions in combination with their relationship to clinical features of SZ suggest that thalamic dysconnectivity may be a core neurobiological feature of SZ that underpins positive symptoms.

Antidepressant-associated mania and psychosis resulting in psychiatric admissions

BACKGROUND

The safety and tolerability of the selective serotonin reuptake inhibitors and the newer atypical agents have led to a significant increase in antidepressant use. These changes raise concern as to the likelihood of a corresponding increase in adverse behavioral reactions attributable to these drugs.

METHOD

All admissions to a university-based general hospital psychiatric unit during a 14-month period were reviewed.

RESULTS

Forty-three (8.1%) of 533 patients were found to have been admitted owing to antidepressant-associated mania or psychosis.

CONCLUSION

Despite the positive changes in the side effect profile of antidepressant drugs, the rate of admissions due to antidepressant-associated adverse behavioral effects remains significant.

Tumor microvascular characterization using ultrasmall superparamagnetic iron oxide particles (USPIO) in an experimental breast cancer model

The diagnostic potential of ultrasmall superparamagnetic iron oxide particles (USPIO) for quantitative tumor microvessel characterization was assessed by kinetic analysis of dynamic magnetic resonance imaging (MRI) in a rodent breast cancer model. Microvascular characteristics (transendothelial permeability (K(PS)) and fractional plasma volume (fPV)) were estimated in 32 female Sprague Dawley rats, bearing breast tumors of varying malignancy. These values were compared to a prototype macromolecular contrast medium standard, albumin-(GdDTPA)(30). Transendothelial permeability (K(PS)) correlated significantly (P < 0.05) with the tumor grade (Scarff-Bloom-Richardson (SBR) score) for the USPIO (r = 0.36), as well as for the reference macromolecule, albumin-(GdDTPA)(30) (r = 0.54). Estimates for the fPV did not show a statistically significant correlation with the tumor grade for either contrast medium. In conclusion, USPIO-enhanced MRI data were capable to characterize tumor microvessel properties in this breast cancer model: microvascular permeability (determined using USPIO) correlated significantly with tumor grade. Thus, quantitative estimation of microvascular characteristics in tumors could provide a surrogate of new vessel formation (angiogenesis) and thus a further important clinical indication for USPIO, in addition to MR angiography. J. Magn. Reson. Imaging 2001;13:882-888.

The influence of disclosure of HIV diagnosis on time to disease progression in a cohort of Romanian children and teens

The Joint United Nations Programme on HIV/AIDS (UNAIDS) estimates that in 2004, there were 39.4 million people living with HIV/AIDS worldwide (UNAIDS/WHO Report on the global HIV/AIDS epidemic, 2004). Children less than 15 years of age comprise 2.2 million of these individuals. As more children globally gain access to highly active antiretroviral therapy (HAART), more children are growing to the age when disclosure of their HIV status is inevitable. This information may affect a child's disease trajectory, and in the context of HAART, may have wide-ranging impact in the management of paediatric HIV infection. This study is an investigation of the effect of disclosure of a child's own HIV infection status on death and CD4 decline in a cohort of 325 HIV-infected Romanian children receiving highly active antiretroviral therapy (HAART). A retrospective database analysis was conducted. Data from a nearly three-year period were examined. Children who were aware of their HIV diagnosis were compared with those who were not aware. We found significant associations between not knowing the HIV diagnosis and death, and not knowing the HIV diagnosis and disease progression defined as either death or CD4 decline. Our results imply that in the context of HAART, knowledge of one's own HIV infection status is associated with delayed HIV disease progression.

Assessment of a rapid clearance blood pool MR contrast medium (P792) for assays of microvascular characteristics in experimental breast tumors with correlations to histopathology

The diagnostic potential of a new rapid clearance blood pool contrast medium (P792; MW = 6.47 kDa) for the MR assessment of microvessel characteristics was assessed in 42 chemically-induced breast tumors, with comparisons to albumin-(Gd-DTPA). Microvessel characteristics, including the transendothelial permeability (K(PS)) and the fractional blood volume (fPV), were estimated by using dynamic MR data fit to a bidirectional two-compartment model. The MR-derived estimates for K(PS) and fPV using each contrast agent were compared, and assays using each contrast agent were correlated to the histologic tumor grade (SBR score) and the microvascular density (MVD) counts. Using P792-enhanced data, neither K(PS) nor fPV showed a statistically significant correlation with the tumor grade or the MVD (P >.05). Conversely, using albumin-(GdDTPA)(30), K(PS) values correlated significantly with the histologic tumor grade (r =.55; P <.0005) and the MVD (r =.34, P <.05), whereas no correlation was established for fPV. In conclusion, based on P792 data no correlation between tumor microvascular characteristics and histologic markers (SBR score or MVD) was found in this breast tumor model. Our analysis suggests that contrast media of relatively large (on the order of 90 kDa) molecular size, such as albumin-(GdDTPA)(30), are more accurate for the characterization of tumor microvessels.

Decreased hemispheric connectivity and decreased intra- and inter- hemisphere asymmetry of resting state functional network connectivity in schizophrenia

Many studies have shown that schizophrenia patients have aberrant functional network connectivity (FNC) among brain regions, suggesting schizophrenia manifests with significantly diminished (in majority of the cases) connectivity. Schizophrenia is also associated with a lack of hemispheric lateralization. Hoptman et al. (2012) reported lower inter-hemispheric connectivity in schizophrenia patients compared to controls using voxel-mirrored homotopic connectivity. In this study, we merge these two points of views together using a group independent component analysis (gICA)-based approach to generate hemisphere-specific timecourses and calculate intra-hemisphere and inter-hemisphere FNC on a resting state fMRI dataset consisting of age- and gender-balanced 151 schizophrenia patients and 163 healthy controls. We analyzed the group differences between patients and healthy controls in each type of FNC measures along with age and gender effects. The results reveal that FNC in schizophrenia patients shows less hemispheric asymmetry compared to that of the healthy controls. We also found a decrease in connectivity in all FNC types such as intra-left (L_FNC), intra-right (R_FNC) and inter-hemisphere (Inter_FNC) in the schizophrenia patients relative to healthy controls, but general patterns of connectivity were preserved in patients. Analyses of age and gender effects yielded results similar to those reported in whole brain FNC studies.

Moving beyond the 'CAP' of the Iceberg: Intrinsic connectivity networks in fMRI are continuously engaging and overlapping

Resting-state functional magnetic resonance imaging is currently the mainstay of functional neuroimaging and has allowed researchers to identify intrinsic connectivity networks (aka functional networks) at different spatial scales. However, little is known about the temporal profiles of these networks and whether it is best to model them as continuous phenomena in both space and time or, rather, as a set of temporally discrete events. Both categories have been supported by series of studies with promising findings. However, a critical question is whether focusing only on time points presumed to contain isolated neural events and disregarding the rest of the data is missing important information, potentially leading to misleading conclusions. In this work, we argue that brain networks identified within the spontaneous blood oxygenation level-dependent (BOLD) signal are not limited to temporally sparse burst moments and that these event present time points (EPTs) contain valuable but incomplete information about the underlying functional patterns. We focus on the default mode and show evidence that is consistent with its continuous presence in the BOLD signal, including during the event absent time points (EATs), i.e., time points that exhibit minimum activity and are the least likely to contain an event. Moreover, our findings suggest that EPTs may not contain all the available information about their corresponding networks. We observe distinct default mode connectivity patterns obtained from all time points (AllTPs), EPTs, and EATs. We show evidence of robust relationships with schizophrenia symptoms that are both common and unique to each of the sets of time points (AllTPs, EPTs, EATs), likely related to transient patterns of connectivity. Together, these findings indicate the importance of leveraging the full temporal data in functional studies, including those using event-detection approaches.

Dynamic contrast-enhanced MRI using macromolecular contrast media for monitoring the response to isolated limb perfusion in experimental soft-tissue sarcomas

The objective of this study was to evaluate the potential of dynamic contrast-enhanced MRI for quantitative characterization of tumor microvessels and to assess the microvascular changes in response to isolated limb perfusion with TNF-alpha and melphalan. Dynamic contrast-enhanced MRI was performed in an experimental cancer model, using a macromolecular contrast medium, albumin-(Gd-DTPA)45. Small fragments of BN 175, a soft-tissue sarcoma, were implanted in 11 brown Norway (BN) rats. Animals were assigned randomly to a control (Haemaccel) or drug-treated group (TNF-alpha/melphalan). MRI was performed at baseline and 24 h after ILP. The transendothelial permeability (K(PS)) and the fractional plasma volume (fPV) were estimated from the kinetic analysis of MR data using a two-compartment bi-directional model. K(PS) and fPV decreased significantly in the drug-treated group compared to baseline (p<0.05). In addition, K(PS) post therapy was significantly lower (p<0.05) in the drug-treated group than in the control group. There was no significant difference in fPV between the drug-treated and the control group after therapy. Tumor microvascular changes in response to isolated limb perfusion can be determined after 24 h by dynamic contrast-enhanced MRI. The data obtained in this experimental model suggest possible applications in the clinical setting, using the appropriate MR contrast agents.

Comparative urologic complications of ureteroneocystostomy in kidney transplantation: transvesical Leadbetter-Politano versus extravesical Lich-Gregoir technique

BACKGROUND

The incidence of urologic complications after kidney transplantation remains high despite improvements in diagnosis and operative techniques. Urinary tract reconstruction is usually done by ureteroneocystostomy (UCNS), and several techniques are available. In this study, we evaluated the outcomes of 2 different UCNS techniques performed in our department, the transvesical Leadbetter-Politano (L-P) and the extravesical Lich-Gregoire (L-G) technique.

MATERIAL AND METHODS

We evaluated the outcomes of 2 different UCNS techniques, L-P versus L-G, performed in our department between July 1, 2006, and December 31, 2011. During this period, we performed 524 consecutive renal transplantations-264 cases using the L-P technique (50.3%) and 260 cases with L-G technique (49.7%). Renal grafts were obtained from cadaveric donors in 146 cases (27.86%) and from living-related donors in 378 cases (72.14%). Recipient mean age was 35.64 years and the male to female ratio was 1.63:1.

RESULTS

Urologic complications after kidney transplantation occurred in 22 cases in the L-P UCNS group (8.33%). The most common complications were ureteral stenosis (3.41%) and leakage (2.65%). Other complications recorded were lymphoceles (1.89%) and hematoma with secondary ureteral obstruction (0.38%). Compared with the L-P UCNS technique, the L-G technique was associated with fewer overall complications (6.15% vs 8.33%; P = .06), a lesser rate of ureteral stenosis (2.31% vs 3.41%; P = .08), and a similar rate of leakage. However, statistical analysis revealed no differences between the 2 techniques (P = .06). In addition, we did not note any differences in graft and patient survival between the 2 groups.

CONCLUSIONS

In our study, the extravesical L-G technique has a lower complication rate compared with transvesical L-P procedure, but without statistical differences. Furthermore, the L-G technique is easier and faster to perform, it avoids a separate cystotomy, and requires a shorter ureteral length. In conclusion, we recommend L-G technique as technique of choice in kidney transplantation.

Magnetic resonance imaging of liver lesions: exceptions and atypical lesions

On state-of-the-art magnetic resonance imaging, most lesions can be detected and characterized with confidence according to well-known criteria. However, atypical characteristics in some common lesions and the incidental encounter with rare lesions may pose diagnostic difficulties. In this article, six challenging hepatic lesions will be discussed and evaluated on the most important magnetic resonance imaging sequences, with histological correlation when available. In addition, the background information concerning these lesions will be described based on the most recent available literature. By reading this article, the reader will be able to (1) categorize the lesion in solid and fluid-containing lesions, based on the T2 signal intensity; and (2) define the benign or malignant nature of the lesion, in relation to the signal intensity and dynamic enhancement pattern, despite the presence of atypical characteristics of some lesions.

Azacytidine plus olaparib for relapsed acute myeloid leukaemia, ineligible for intensive chemotherapy, diagnosed with a synchronous malignancy

Patients with relapsed/refractory acute myeloid leukaemia (AML), ineligible for intensive chemotherapy and allogeneic stem cell transplantation, have a dismal prognosis. For such cases, hypomethylating agents are a viable alternative, but with limited success. Combination chemotherapy using a hypomethylating agent plus another drug would potentially bring forward new alternatives. In the present manuscript, we present the cell and molecular background for a clinical scenario of a 44-year-old patient, diagnosed with high-grade serous ovarian carcinoma, diagnosed, and treated with a synchronous AML. Once the ovarian carcinoma relapsed, maintenance treatment with olaparib was initiated. Concomitantly, the bone marrow aspirate showed 30% myeloid blasts, consistent with a relapse of the underlying haematological disease. Azacytidine 75 mg/m2 treatment was started for seven days. The patient was administered two regimens of azacytidine monotherapy, additional to the olaparib-based maintenance therapy. After the second treatment, the patient presented with leucocytosis and 94% myeloid blasts on the bone marrow smear. Later, the patient unfortunately died. Following this clinical scenario, we reproduced in vitro the combination chemotherapy of azacytidine plus olaparib, to accurately assess the basic mechanisms of leukaemia progression, and resistance to treatment. Combination chemotherapy with drugs that theoretically target both malignancies might potentially be of use. Still, further research, both pre-clinical and clinical, is needed to accurately assess such cases.

Paraneoplastic hypereosinophilia in a patient with peripheral T cell lymphoma, not otherwise specified

Under normal physiological conditions, the bone marrow (BM) will have between 1% and 6% eosinophils, translating into a peripheral count of 0.05 – 0.5 ×10⁹/L eosinophils in the blood smear. This process is coordinated by transcription factors with specific roles in differentiation and activation. Secondary eosinophilia may be a paraneoplastic syndrome, related to the presence of a subsequent malignancy, as presented in this case report. Such paraneoplastic manifestations should be addressed properly in order for the patient to receive the best treatment of choice. Even if eosinophilia was associated with B-cell malignancies before, this is a report associating this symptom to a peripheral T-cell lymphoma, not other specified, thus emphasizing the importance of a complex approach for the management of the oncological patient.

Dapagliflozin Ameliorates Neural Damage in the Heart and Kidney of Diabetic Mice

(1) Background: Measures for the control of diabetes mellitus (DM) and, especially, for the control of its complications represent a main objective of the research carried out on this disease, since both mortality and morbidity relating to DM represent real problems for the health system worldwide. The aim of our study was to evaluate nervous tissue from the heart and kidneys of mice with diabetes induced by streptozotocin (STZ) in the presence or absence of dapagliflozin (DAPA) treatment. (2) Methods: For this purpose, we used 24 C 57Bl/6 male mice, aged between 8 and 10 weeks. The mice were divided into three groups: sham (DM-), control (DM+), and treated (DM+). Diabetes mellitus was induced by injecting a single intraperitoneal dose of STZ. The duration of diabetes in the mice included in our study was 12 weeks after STZ administration; then, the heart and kidneys were sampled, and nervous tissue (using the primary antibody PGP 9.5) from the whole heart, from the atrioventricular node, and from the kidneys was analyzed. (3) Results: The density of nerve tissue registered a significant decrease in animals from the control group (DM+), to a value of 0.0122 ± 0.005 mm2 nerve tissue/mm2 cardiac tissue, compared with the sham group (DM-), wherein the value was 0.022 ± 0.006 mm2 nervous tissue/mm2 cardiac tissue (p = 0.004). Treatment with dapagliflozin reduced the nerve tissue damage in the treated (DM+DAPA) group of animals, resulting in a nerve tissue density of 0.019 ± 0.004 mm2 nerve tissue/mm2 cardiac tissue; a statistically significant difference was noted between the control (DM+) and treated (DM+DAPA) groups (p = 0.046). The same trends of improvement in nerve fiber damage in DM after treatment with DAPA were observed both in the atrioventricular node and in the kidneys. (4) Conclusions. These data suggest that dapagliflozin, when used in streptozotocin-induced diabetes in mice, reduces the alteration of the nervous system in the kidneys and in the heart, thus highlighting better preservation of cardiac and renal homeostasis, independent of any reduction in the effects of hyperglycemia produced in this disease.

5-Azacytidine treatment inhibits the development of lung cancer models via epigenetic reprogramming and activation of cellular pathways with anti-tumor activity

Background and aims

Non-small cell lung cancer (NSCLC) treatment is challenged by late detection and limited therapeutic options. Aberrant DNA methylation, a common epigenetic alteration in NSCLC, offers new therapeutic avenues. This study aims to evaluate the combined effects of 5-Azacytidine (5-Aza), an epigenetic modifier, and ionizing radiation (IR) on NSCLC, exploring the underlying molecular mechanisms and therapeutic potential.

Methods

In this study, we examined the effects of 5-Aza combined with IR in both in vitro and in vivo models of NSCLC. Five human NSCLC cell lines were treated with 5-Aza and IR. Cell viability, colony formation, wound healing, and transwell migration assays were performed to assess treatment effects. Microarray and qPCR analyses were conducted to identify gene expression changes. Additionally, subcutaneous and orthotopic xenograft models were used to evaluate the treatment's efficacy in vivo.

Results

Treatment with 5-Aza and IR resulted in significant reductions in cell viability, colony formation, and migration in NSCLC cell lines. Microarray analysis revealed significant changes in gene expression, including the upregulation of apoptosis-related genes and the downregulation of cell proliferation-related genes. In vivo studies demonstrated a notable reduction in tumor growth and metastasis in both subcutaneous and orthotopic NSCLC models following 5-Aza and IR treatment. Histological and bioluminescent imaging confirmed the therapeutic effects of the combined treatment.

Conclusions

The combination of 5-Aza and IR shows promise as an effective treatment for NSCLC, enhancing apoptosis and reducing tumor growth through epigenetic modulation.

A method for estimating and characterizing explicitly nonlinear dynamic functional network connectivity in resting-state fMRI data

The past 10 years have seen an explosion of approaches that focus on the study of time-resolved change in functional connectivity (FC). FC characterization among networks at a whole-brain level is frequently termed functional network connectivity (FNC). Time-resolved or dynamic functional network connectivity (dFNC) focuses on the estimation of transient, recurring, whole-brain patterns of FNC. While most approaches in this area have attempted to capture dynamic linear correlation, we are particularly interested in whether explicitly nonlinear relationships, above and beyond linear, are present and contain unique information. This study thus proposes an approach to assess explicitly nonlinear dynamic functional network connectivity (EN dFNC) derived from the relationship among independent component analysis time courses. Linear relationships were removed at each time point to evaluate, typically ignored, explicitly nonlinear dFNC using normalized mutual information (NMI). Simulations showed the proposed method estimated explicitly nonlinearity over time, even within relatively short windows of data. We then, applied our approach on 151 schizophrenia patients, and 163 healthy controls fMRI data and found three unique, highly structured, mostly long-range, functional states that also showed significant group differences. In particular, explicitly nonlinear relationships tend to be more widespread than linear ones. Results also highlighted a state with long range connections to the visual domain, which were significantly reduced in schizophrenia. Overall, this work suggests that quantifying EN dFNC may provide a complementary and potentially valuable tool for studying brain function by exposing relevant variation that is typically ignored.

Outcomes of patients with cancer infected with SARS-CoV-2: results from the Ion Chiricuță Oncology Institute series

Background

The evolution of COVID-19 is a controversial topic in cancer patients. They have been designated by international organizations as a vulnerable population at greater risk for contracting SARS-CoV-2 and having a more severe clinical outcome.

Patients and methods

Active screening at our institution became routine early in the pandemic. We have examined the clinical data of 341 cancer patients, with a positive RT-PCR SARS-CoV-2 test between April 2020 and February 2021, in the prevaccination era.

Results

During the infection, 40.5% remained asymptomatic, 27.6% developed a mild form, 20.5% had a moderate form, and 11.4% a severe/critical form of COVID-19 that led to death in 7.6% of cases. Treatment was adapted to disease severity according to national guidelines. In our series, the incidence of COVID-19 infection was lower in cancer patients compared with the general population (P < 0.001), however, the mortality rate was higher in cancer patients in comparison with the general population (7.6% versus 2.9%, P < 0.001). The prognostic factors were assessed by three distinct univariate and multivariate analyses: (i) evolution to a moderate or severe/critical clinical manifestation, (ii) clinical worsening (severe/critical form or death), and (iii) overall survival. In the multivariate analysis, the prognostic factors associated with the evolution to a moderate or severe/critical clinical manifestation were: performance status (PS) (P < 0.0001) and no active treatment in the previous 3 months (P = 0.031). Factors associated with clinical worsening were: PS (P < 0.0001), peripheral arterial disease (P = 0.03), and chronic liver disease (P = 0.04). Factors associated with impaired overall survival were PS (P < 0.0001), ischemic cardiac disease (P = 0.0126), chronic liver disease (P = 0.001), and radiotherapy (P = 0.0027).

Conclusion

Our series confirms a more severe evolution for COVID-19 infection in cancer patients, with PS as the most prominent prognostic factor in all three multivariate analyses. By active screening, efforts should be in place to keep cancer units as coronavirus-free sanctuaries.

•

This is the first comprehensive study addressing the impact of COVID-19 in a large cohort of cancer patients in Romania.

•

Oncological patients had a higher death rate after COVID-19 infection in comparison with the general population.

•

Decreased PS was the prominent prognostic factor correlated with worse outcomes and death in multiple multivariate analysis.