Liposomes - Human phagocytes interplay in whole blood: effect of liposome design.

Nanomedicine holds immense potential for therapeutic manipulation of phagocytic immune cells. However, in vitro studies often fail to accurately translate to the complex in vivo environment. To address this gap, we employed an ex vivo human whole-blood assay to evaluate liposome interactions with immune cells. We systematically varied liposome size, PEG-surface densities and sphingomyelin and ganglioside content. We observed differential uptake patterns of the assessed liposomes by neutrophils and monocytes, emphasizing the importance of liposome design. Interestingly, our results aligned closely with published in vivo observations in mice and patients. Moreover, liposome exposure induced changes in cytokine release and cellular responses, highlighting the potential modulation of immune system. Our study highlights the utility of human whole-blood models in assessing nanoparticle-immune cell interactions and provides insights into liposome design for modulating immune responses.

Positron emission tomography/computed tomography and biomarkers for early treatment response evaluation in metastatic colon cancer.

BACKGROUND: Treatment options for metastatic colon cancer (mCC) are widening. We prospectively evaluated serial 2-deoxy-2-[18F]fluoro-d-glucose positron-emission tomography/computed tomography (PET/CT) and measurements of tissue inhibitor of metalloproteinases-1 (TIMP-1), carcinoembryonic antigen (CEA), and liberated domain I of urokinase plasminogen activator receptor (uPAR(I)) for early assessment of treatment response in mCC patients. METHODS: Thirty-three mCC patients scheduled for first-line chemotherapy with capecitabine and oxaliplatin (CAPOX) and bevacizumab participated; 27 were evaluated by PET/CT before treatment, after one and four treatment series. Morphological and metabolic response was independently assessed according to Response Evaluation Criteria in Solid Tumors and European Organization for Research and Treatment of Cancer PET criteria. Plasma TIMP-1, plasma uPAR(I), and serum CEA were determined. RESULTS: Metabolic response after one treatment course predicted the ability of CAPOX and bevacizumab to induce morphological response after four treatment series with a sensitivity of 80%, specificity of 69%, and odds ratio of 13.9 (95% confidence interval [CI] 1.9; 182). Early metabolically stable or progressive disease was associated with shorter progression-free survival (hazard ratio [HR] = 3.2 [CI 1.3; 7.8]). Biomarker levels at early evaluation were associated with shorter OS (TIMP-1 per unit increase on a log-2-transformed ng/mL scale: HR = 2.6 [CI 1.4; 4.9]; uPAR(I) per 25 fmol/mL increase: HR = 1.5 [CI 1.1; 2.1]). CONCLUSION: This monocentric study demonstrated predictive value of early metabolic PET response and prognostic value of TIMP-1 and uPAR(I) levels in mCC treated with CAPOX and bevacizumab. Results support investigation of PET/CT, TIMP-1, and uPAR(I) guided early treatment adaptation in mCC.

Mechanisms of heat shock response in mammals.

Heat shock (HS) is one of the best-studied exogenous cellular stresses. The cellular response to HS utilizes ancient molecular networks that are based primarily on the action of stress-induced heat shock proteins and HS factors. However, in one way or another, all cellular compartments and metabolic processes are involved in such a response. In this review, we aimed to summarize the experimental data concerning all aspects of the HS response in mammalian cells, such as HS-induced structural and functional alterations of cell membranes, the cytoskeleton and cellular organelles; the associated pathways that result in different modes of cell death and cell cycle arrest; and the effects of HS on transcription, splicing, translation, DNA repair, and replication.

Chronic appendicitis: two case reports.

BACKGROUND: Chronic appendicitis is a condition unfamiliar to many physicians and is often referred to as a controversial diagnosis. This can give rise to diagnostic delay. CASE PRESENTATION: We present two cases of chronic appendicitis: a Caucasian female aged 21 years and a Caucasian male aged 34 years. The patients had different clinical presentations, which led the initial investigations in very different directions-tropical infectious disease and possible malignancy, respectively. In both cases, radiological imaging was the key investigation leading to the final surprising diagnosis. CONCLUSION: With these two case stories, we wish to draw attention to chronic appendicitis as a possible differential diagnosis in younger patients with chronic or recurrent abdominal pain, particularly if the pain is located in the lower abdomen and is accompanied by fever.

Design and evaluation of nanostructured lipid carriers loaded with Salvia officinalis extract for Alzheimer's disease treatment.

Considering the potential of Salvia officinalis in prevention and treatment of Alzheimer's disease (AD), as well as the ability of nanostructured lipid carriers (NLC) to successfully deliver drug molecules across blood-brain barrier (BBB), the objective of this study was design, development, optimization and characterization of freeze-dried salvia officinalis extract (FSE) loaded NLC intended for intranasal administration. NLC were prepared by solvent evaporation method and the optimization was carried out using central composite design (CCD) of experiments. Further, the optimized formulation (NLCo) was coated either with chitosan (NLCc) or poloxamer (NLCp). Surface characterization of the particles demonstrated a spherical shape with smooth exterior. Particle size of optimal formulations after 0.45 µm pore size filtration ranged from 127 ± 0.68 nm to 140 ± 0.74 nm. The zeta potential was -25.6 ± 0.404 mV; 22.4 ± 1.106 mV and - 6.74 ± 0.609 mV for NLCo, NLCc, and NLCp, respectively. Differential scanning calorimetry (DSC) confirmed the formation of NLC whereas Fourier-transform infrared spectroscopy confirmed the FSE encapsulation into particles. All formulations showcased relatively high drug loading (>86.74 mcg FSE/mg solid lipid) and were characterized by prolonged and controlled release that followed Peppas-Sahlin in vitro release kinetic model. Protein adsorption studies revealed the lowest adsorption of the proteins onto NLCp (43.53 ± 0.07%) and highest protein adsorption onto NLCc (55.97 ± 0.75%) surface. The modified ORAC assay demonstrated higher antioxidative activity for NLCo (95.31 ± 1.86%) and NLCc (97.76 ± 4.00%) as compared to FSE (90.30 ± 1.53%). Results obtained from cell cultures tests pointed to the potential of prepared NLCs for FSE brain targeting and controlled release.

Transcriptional regulation and spatial organisation of the human AML1/RUNX1 gene.

The transcription factor RUNX1 is a key regulator of haematopoiesis in vertebrates. In humans, the 260-kb long gene coding for this transcription factor is located on chromosome 21. This gene is transcribed from two alternative promoters that are commonly referred to as the distal and the proximal promoters. In model experiments, these two promoters were found to be active in cells of different lineages, although RUNX1 is preferentially expressed in haematopoietic cells. In the present study, we attempted to identify the regulatory elements that could guide tissue-specific expression of the RUNX1 gene. Two such regulatory elements were found within the RUNX1 gene. One of these elements, located within intron 1, is a haematopoietic-specific enhancer. The second regulatory element, located within intron 5.2, contributes to the formation of an active chromatin hub, which integrates the above-mentioned enhancer and the P1 and P2 promoters.

Influence of 2-(18F) fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography on recurrent ovarian cancer diagnosis and on selection of patients for secondary cytoreductive surgery.

The objective of this prospective study was to compare the sensitivities and the specificities of combined 2-(F) fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (PET/CT), abdominal/transvaginal ultrasound (US), and CT for diagnosing recurrent ovarian cancer (OC) and to evaluate the influence of PET/CT on referral of patients with solitary recurrence to secondary cytoreductive surgery. From April 2005 to November 2007, 60 patients were consecutively included to PET/CT 68 times. The inclusion criteria were remission of 3 months or longer and recurrent OC suspected from physical examination, US, or increasing cancer antigen 125 (CA125) level (>50 U/mL or >15% above baseline level). Recurrent OC was diagnosed 58 times in 52 patients. The sensitivities of US, CT, and PET/CT for diagnosing recurrence were 66% (P = 0.003), 81% (P = 0.0001), and 97% (P < 0.0001), respectively. The specificity of US, CT, and PET/CT for diagnosing recurrence was 90%. Positron emission tomography/CT diagnosed recurrence in 19 (66%) of 29 patients without recurrence according to US and in 10 (50%) of 20 patients without recurrence after CT. Multiple recurrent tumors were found using PET/CT in 27 (69%) of 39 patients with solitary tumors on US and in 8 (42%) of 19 patients with solitary tumors on CT. We conclude that the diagnostic value of PET/CT for detecting recurrent OC was higher than those of US and CT and that PET/CT more accurately identified patients with solitary recurrence. However, prospective clinical trials are needed to specify the characteristics of patients most likely to undergo complete secondary surgery and to further clarify the role of PET/CT in selecting patients for secondary surgery.

The Epithelial-Mesenchymal Transition, E-cadherin and Tumor Progression in Ovarian Serous Tumors.

BACKGROUND: The epithelial-mesenchymal transition (EMT), which is a change in the cell phenotype from epithelial to mesenchymal morphology, is an important step in the invasion process and metastasis of ovarian carcinomas. It is known that the suppression of cell adhesion molecules such as E-cadherin and the expression of mesenchymal markers such as Vimentin are key processes in EMT. There is controversy in the literature about the EMT status of ovarian carcinomas. AIM: To investigate EMT status using immunohistochemical expression of E-cadherin in benign, primary malignant serous ovarian tumors and metastases from them in order to assess their significance in tumor progression. MATERIALS AND METHODS: The study included a retrospective investigation of 217 ovarian epithelial tumors. Ninety-two cases of serous ovarian tumors and metastases were examined for expression of E-cadherin. RESULTS: In our study, the predominant histological subtype in benign ovarian tumors and carcinomas was serous (73% and 61%, respectively). 65% of benign tumors demonstrated EMT negative status. The majority of carcinomas demonstrated EMT positive status (82%), whereas negative EMT status was only observed in 18% of cases. 89% of the metastases showed EMT positive status, whereas only 11% of them showed negative EMT status. In 6 selected cases with positive EMT status we found Vimentin expression in tumor cells. CONCLUSION: Positive EMT status (reduced E-cadherin expression) is a characteristic of ovarian carcinomas and metastases, but not of benign serous ovarian tumors.

18F-FDG PET/CT Findings in Cytomegalovirus Colitis.

We present a case demonstrating the diagnostic work-up of a patient undergoing azathioprine treatment for inflammatory bowel disease (IBD), diagnosed with an acute cytomegalovirus (CMV) infection and CMV colitis. An 18F-FDG positron emission tomography/computed tomography (PET/CT) performed 2 weeks after debut of symptoms revealed pathological 18F-FDG uptake in the left side of the colon mucosa, mimicked activity of IBD. However, a diagnosis of CMV colitis was based on the presence of CMV IgM antibodies, a seroconversion of CMV IgG antibodies, presence of CMV DNA in plasma and the finding af CMV DNA in biopsies from the intestinal mucosa. The patient responded to treatment with ganciclovir. This case highlights that a positive 18F-FDG PET/CT scan of the colon can be due to CMV colitis.

Nikolai V. Konovalov (1900-1966): his role in the development of neurology and the creation of the Institute of Neurology of the Russian Academy of Medical Sciences.

Nikolai V. Konovalov (1900-1966) has left a significant imprint in the history of Russian neuroscience. He was among the coryphaei of international and national neurology. Along with the large number of fundamental scientific papers that have determined several aspects of the development of neuroscience, his contribution has been equally important to the establishment and development of one of the distinguished Russian scientific centers - the Institute of Neurology of the Russian Academy of Medical Sciences, which he headed from 1948 until 1966.

18F-FDG PET/CT Findings in a Patient with Chikungunya Virus Infection.

We present a case demonstrating the diagnostic work-up and follow-up of a patient with Chikungunya infection. An 18F-FDG PET/CT performed four weeks after debut of symptoms revealed pathological 18F-FDG uptake in enlarged lymph nodes on both side of the diaphragm, and inflammation of both shoulder and hip joints. Lymphoma and infection were the main differential diagnoses. Follow-up 18F-FDG PET/CT scan in the patient performed 14 weeks after the abnormal scan, revealed almost complete resolution of the metabolically active disease. This case is to our knowledge the first to demonstrate sequential 18F-FDG PET/CT scan results in a patient with Chikungunya virus infection.

Whole-Body 18F-FDG PET/CT Is Superior to CT as First-Line Diagnostic Imaging in Patients Referred with Serious Nonspecific Symptoms or Signs of Cancer: A Randomized Prospective Study of 200 Patients.

A fast-track pathway has been established in Denmark to investigate patients with serious nonspecific symptoms and signs of cancer (NSSC), who are not eligible to enter an organ-specific cancer program. The prevalence of cancer in this cohort is approximately 20%. The optimal screening strategy in patients with NSSC remains unknown. The aim of the study was to investigate whether 18F-FDG PET/CT was superior to CT as an initial imaging modality in patients with NSSC. In a randomized prospective trial, the imaging modalities were compared with regard to diagnostic performance. Methods: Two hundred patients were randomized 1:1 to whole-body 18F-FDG PET/CT or CT of the thorax and abdomen as the imaging modality. A tentative diagnosis was established after first-line imaging. The final referral diagnosis was adjudicated by the physician, when sufficient data were available. Results: One hundred ninety-seven patients were available for analysis because 3 patients withdrew consent before scanning. Thirty-nine (20%) patients were diagnosed with cancer, 10 (5%) with an infection, 15 (8%) with an autoimmune disease, and 76 (39%) with other diseases. In the remaining 57 patients (28%), no specific disease was found. 18F-FDG PET/CT had a higher specificity (96% vs. 85%; P = 0.028) and a higher accuracy (94% vs. 82%; P = 0.017) than CT. However, there were no statistically significant differences in sensitivity (83% vs. 70%) or negative predictive values (96% vs. 92%). No difference in days to final referral diagnosis according to randomization group could be shown (7.2 vs. 7.6 d). However, for the subgroups in which the imaging modality showed a suggestion of malignancy, there was a significant delay to final diagnosis in the CT group compared with the 18F-FDG PET/CT group (11.6 vs. 5.7 d; P = 0.02). Conclusion: Compared with CT, we found a higher diagnostic specificity and accuracy of 18F-FDG PET/CT for detecting cancer in patients with NSSC. 18F-FDG PET/CT should therefore be considered as first-line imaging in this group of patients.

(18)F-FDG PET/CT Findings in Acute Epstein-Barr Virus Infection Mimicking Malignant Lymphoma.

We present a case demonstrating the diagnostic work-up and follow-up of a patient with acute Epstein-Barr virus (EBV) infection in which the clinical picture and imaging on (18)F-FDG PET/CT mimicked malignant lymphoma. Follow-up (18)F-FDG PET/CT scan in the patient performed 7 weeks after the abnormal scan revealed complete resolution of the metabolically active disease in the neck, axillas, lung hili, and spleen. This case highlights inflammation as one of the most well established false positives when interpreting (18)F-FDG PET/CT scans.

Transcription of the AML1/ETO chimera is guided by the P2 promoter of the AML1 gene in the Kasumi-1 cell line.

Chromosomal translocation t (8;21)(q22;22) is one of the most frequent cytogenetic abnormalities found in acute myeloid leukaemia (AML). It generates the AML1/ETO fusion gene, which itself supports human haematopoietic stem cell self-renewal. However, the mechanism guiding transcription of this chimeric gene remains unclear. In our work, we attempted to shed light on this essential issue. We investigated the promoter from which transcription of the AML1/ETO gene is initiated and defined the three-dimensional structure of the whole rearranged locus.

Distinct distribution of ectopically expressed histone variants H2A.Bbd and MacroH2A in open and closed chromatin domains.

BACKGROUND: It becomes increasingly evident that nuclesomes are far from being identical to each other. This nucleosome diversity is due partially to the existence of histone variants encoded by separate genes. Among the known histone variants the less characterized are H2A.Bbd and different forms of macroH2A. This is especially true in the case of H2A.Bbd as there are still no commercially available antibodies specific to H2A.Bbd that can be used for chromatin immunoprecipitation (ChIP). METHODS: We have generated HeLa S3 cell lines stably expressing epitope-tagged versions of macroH2A1.1, H2A.Bbd or canonical H2A and analyzed genomic distribution of the tagged histones using ChIP-on-chip technique. RESULTS: The presence of histone H2A variants macroH2A1.1 and H2A.Bbd has been analyzed in the chromatin of several segments of human chromosomes 11, 16 and X that have been chosen for their different gene densities and chromatin status. Chromatin immunoprecipitation (ChIP) followed by hybridization with custom NimbleGene genomic microarrays demonstrated that in open chromatin domains containing tissue-specific along with housekeeping genes, the H2A.Bbd variant was preferentially associated with the body of a subset of transcribed genes. The macroH2A1.1 variant was virtually absent from some genes and underrepresented in others. In contrast, in closed chromatin domains which contain only tissue-specific genes inactive in HeLa S3 cells, both macroH2A1.1 and H2A.Bbd histone variants were present and often colocalized. CONCLUSIONS: Genomic distribution of macro H2A and H2A.Bbd does not follow any simple rule and is drastically different in open and closed genomic domains.

Mutation analysis of the parkin gene in Russian families with autosomal recessive juvenile parkinsonism.

Autosomal recessive juvenile parkinsonism (AR-JP) is a form of hereditary parkinsonism characterized by variable clinical presentations and caused by mutations in a novel gene, parkin, on chromosome 6q25.2-27. Until now, no Russian cases of parkin-associated AR-JP have been reported on. We recruited 16 patients from 11 Russian families with dopa-responsive movement disorders according to the following criteria: 1) family history compatible with autosomal recessive inheritance; 2) onset of symptoms at A). The majority of our parkin-associated cases were characterized by early-onset dopa-responsive parkinsonism with benign course and slow progression (5 patients from two families have been followed for as long as 18-36 years), and 1 patient had a phenotype of dopa-responsive dystonia. This first description of Russian patients with AR-JP and molecularly proven parkin mutations confirms the widespread occurrence of this polymorphic hereditary extrapyramidal disorder.