Oligoclonal gammopathy: An analysis of 253 cases

BACKGROUND

Oligoclonal gammopathy (OG) is a rare disorder of the lymphoid system that is characterized by the presence of at least 2 distinct monoclonal proteins in a patient's serum or urine. The biological and clinical characteristics of this disease are as yet poorly understood.

OBJECTIVES

The study aimed to assess whether there are significant differences between patients with OG regarding the developmental history (i.e., OG diagnosed at the first presentation compared to OG that has developed in patients with an original monoclonal gammopathy) and the number of monoclonal proteins (2 compared to 3). Moreover, we attempted to determine when secondary oligoclonality develops following the original diagnosis of monoclonal gammopathy.

MATERIAL AND METHODS

Patients were analyzed with regard to their age at diagnosis, sex, serum monoclonal proteins, and underlying hematological disorders. Multiple myeloma (MM) patients were additionally evaluated for their Durie-Salmon stage and cytogenetic alterations.

RESULTS

Patients with triclonal gammopathy (TG: n = 29) did not differ significantly from patients with biclonal gammopathy (BG: n = 223) (p = 0.81) in terms of age at diagnosis and the dominant diagnosis (MM was the most common diagnosis (65.0% and 64.7%, respectively)). In both cohorts, myeloma patients were mainly classified to the Durie-Salmon stage III. In the TG cohort, there was a higher proportion of males (69.0%) than among patients with BG (52.5%). Oligoclonality developed at various times after diagnosis (up to 80 months in the investigated cohort). However, the occurrence of new cases was higher during the initial 30-month period following the diagnosis of monoclonal gammopathy.

CONCLUSIONS

There are only small differences between patients with primary compared to secondary OG, between BG and TG, and most patients have a combination of IgGκ+IgGλ. Oligoclonality could develop at any time after the diagnosis of monoclonal gammopathy, but it happens more frequently during the first 30 months, with advanced myeloma being the most prevalent underlying disorder.

The Concept of Creating Digital Twins of Bridges Using Load Tests

The paper sheds light on the process of creating and validating the digital twin of bridges, emphasizing the crucial role of load testing, BIM models, and FEM models. At first, the paper presents a comprehensive definition of the digital twin concept, outlining its core principles and features. Then, the framework for implementing the digital twin concept in bridge facilities is discussed, highlighting its potential applications and benefits. One of the crucial components highlighted is the role of load testing in the validation and updating of the FEM model for further use in the digital twin framework. Load testing is emphasized as a key step in ensuring the accuracy and reliability of the digital twin, as it allows the validation and refinement of its models. To illustrate the practical application and issues during tuning and validating the FEM model, the paper provides an example of a real bridge. It shows how a BIM model is utilized to generate a computational FEM model. The results of the load tests carried out on the bridge are discussed, demonstrating the importance of the data obtained from these tests in calibrating the FEM model, which forms a critical part of the digital twin framework.

One-Pot Synthesis of 1-Aryl-3-trifluoromethylpyrazoles Using Nitrile Imines and Mercaptoacetaldehyde As a Surrogate of Acetylene

A synthetically useful approach for one-pot preparation of 1-aryl-3-trifluoromethylpyrazoles using in situ generated nitrile imines and mercaptoacetaldehyde applied as 1 equiv of acetylene is presented. This protocol comprises (3 + 3)-annulation of the mentioned reagents to form 5,6-dihydro-5-hydroxy-4H-1,3,4-thiadiazine, followed by cascade dehydration/ring contraction reactions with p-TsCl. In addition, representative nonfluorinated analogues functionalized with Ph, Ac, and CO₂Et groups at the C(3)-position of the pyrazole ring were also prepared by the devised method.

Regioselective [3 + 2] cycloaddition of di/trifluoromethylated hydrazonoyl chlorides with fluorinated nitroalkenes: a facile access to 3-di/trifluoroalkyl-5-fluoropyrazoles

Herein we describe the base-mediated [3 + 2] cycloaddition reaction of di/trifluoromethylated hydrazonoyl chlorides with fluorinated nitroalkenes. The reaction protocol provides a direct and facile strategy for the dual incorporation of a fluorine atom and fluoroalkyl group into pyrazole cores, thus allowing rapid access to a wide variety of densely functionalized 3-di/trifluoroalkyl-5-fluoropyrazoles in generally high yields with excellent regioselectivities. Furthermore, several drug-like 3-di/trifluoroalkyl-5-fluoropyrazoles have been synthesized, demonstrating potent inhibitory activities against cyclooxygenase 2 (COX-2).

Trifluoromethylated 4,5-Dihydro-1,2,4-triazin-6(1H)-ones via (3+3)-Annulation of Nitrile Imines with α-Amino Esters

The synthesis of two series of monocyclic and bicyclic trifluoromethylated 4,5-dihydro-1,2,4-triazin-6(1H)-one derivatives based on (3+3)-annulation of methyl esters derived from natural α-amino acids with in situ generated trifluoroacetonitrile imines has been described. The devised protocol is characterized by a wide scope, easily accessible substrates, remarkable functional group tolerance, and high chemical yield. In reactions with chiral starting materials, no racemization at the stereogenic centers was observed and the respective enantiomerically pure products were obtained. Selected functional group interconversions carried out under catalytic hydrogenation and mild PTC oxidation conditions were also demonstrated.

Evaluation of the usefulness of determining the level of selected inflammatory biomarkers and resistin concentration in perivascular adipose tissue and plasma for predicting postoperative atrial fibrillation in patients who underwent myocardial revascularisation

BACKGROUND

The development of coronary artery disease (CAD) is related to the impaired quantity and composition of inflammatory proteins found in plasma and tissue, such as interleukin 6 (IL-6), adipokines, and resistin. Therefore, the level of plasma resistin in patients with advanced CAD could be indicative of the condition of epicardial adipose tissue and thus have an impact on the frequency and severity of postoperative complications in the form of paroxysmal atrial fibrillation.

METHODS

The study included 108 patients who qualified for elective coronary artery bypass grafting (CABG) surgery from 2017 to 2020 and were categorized into two groups. The first group consisted of patients who developed atrial fibrillation in the postoperative period - the AF group, and the second group included patients who did not have arrhythmia - the non-AF group. The analysis incorporates the history, course of treatment, anthropometric characteristics of the test subjects, biochemical laboratory tests, and echocardiography. Perivascular adipose tissue (PVAT) sections were surgically harvested from the area of the left coronary trunk.

RESULTS

The resistin levels in the PVAT were significantly higher in the AF group than in the non-AF group (P = 0.000015). Similarly, plasma resistin levels increased significantly in the AF group compared to the non-AF group (P = 0.044). The values of other analyzed variables were not significantly different (analysis performed using the Mann-Whitney U test). Spearman's rank-order correlation technique found a correlation between resistin in PVAT and plasma (r = 0.5933; P < 0.0001) in the whole study group, as well as in the AF group (r = 0.4782; P = 0.021) and the non-AF group (r = 0.4938; P < 0.0001). A correlation arose between the level of resistin in PVAT and the level of hsCRP (r = 0.3463; P = 0.005) in the whole study group and the non-AF group (r = 0.4448; P = 0.0011); however, no such correlation appeared in the AF group (r = 0.3076; P = 0.306).

CONCLUSIONS

Elevated levels of plasma resistin, which reflect PVAT resistin levels in patients qualified for myocardial revascularisation, may be associated with postoperative atrial fibrillation complications.

Next generations of CAR-T cells - new therapeutic opportunities in hematology?

In recent years, the introduction of chimeric antigen receptor (CAR) T-cell therapies into clinics has been a breakthrough in treating relapsed or refractory malignancies in hematology and oncology. To date, Food and Drug Administration (FDA) has approved six CAR-T therapies for specific non-Hodgkin lymphomas, B-cell acute lymphoblastic leukemia, and multiple myeloma. All registered treatments and most clinical trials are based on so-called 2nd generation CARs, which consist of an extracellular antigen-binding region, one costimulatory domain, and a CD3z signaling domain. Unfortunately, despite remarkable overall treatment outcomes, a relatively high percentage of patients do not benefit from CAR-T therapy (overall response rate varies between 50 and 100%, with following relapse rates as high as 66% due to limited durability of the response). Moreover, it is associated with adverse effects such as cytokine release syndrome and neurotoxicity. Advances in immunology and molecular engineering have facilitated the construction of the next generation of CAR-T cells equipped with various molecular mechanisms. These include additional costimulatory domains (3rd generation), safety switches, immune-checkpoint modulation, cytokine expression, or knockout of therapy-interfering molecules, to name just a few. Implementation of next-generation CAR T-cells may allow overcoming current limitations of CAR-T therapies, decreasing unwanted side effects, and targeting other hematological malignancies. Accordingly, some clinical trials are currently evaluating the safety and efficacy of novel CAR-T therapies. This review describes the CAR-T cell constructs concerning the clinical application, summarizes completed and ongoing clinical trials of next-generation CAR-T therapies, and presents future perspectives.

The Role of the Crosstalk Between Gut Microbiota and Immune Cells in the Pathogenesis and Treatment of Multiple Myeloma

Around 10% of all hematologic malignancies are classified as multiple myeloma (MM), the second most common malignancy within that group. Although massive progress in developing of new drugs against MM has been made in recent years, MM is still an incurable disease, and every patient eventually has relapse refractory to any known treatment. That is why further and non-conventional research elucidating the role of new factors in MM pathogenesis is needed, facilitating discoveries of the new drugs. One of these factors is the gut microbiota, whose role in health and disease is still being explored. This review presents the continuous changes in the gut microbiota composition during our whole life with a particular focus on its impact on our immune system. Additionally, it mainly focuses on the chronic antigenic stimulation of B-cells as the leading mechanism responsible for MM promotion. The sophisticated interactions between microorganisms colonizing our gut, immune cells (dendritic cells, macrophages, neutrophils, T/B cells, plasma cells), and intestinal epithelial cells will be shown. That article summarizes the current knowledge about the initiation of MM cells, emphasizing the role of microorganisms in that process.

The Role of Fecal Microbiota Transplantation in the Treatment of Acute Graft-versus-Host Disease

The number of allogeneic hematopoietic stem cell transplantations conducted worldwide is constantly rising. Together with that, the absolute number of complications after the procedure is increasing, with graft-versus-host disease (GvHD) being one of the most common. The standard treatment is steroid administration, but only 40–60% of patients will respond to the therapy and some others will be steroid-dependent. There is still no consensus regarding the best second-line option, but fecal microbiota transplantation (FMT) has shown encouraging preliminary and first clinically relevant results in recent years and seems to offer great hope for patients. The reason for treatment of steroid-resistant acute GvHD using this method derives from studies showing the significant immunomodulatory role played by the intestinal microbiota in the pathogenesis of GvHD. Depletion of commensal microbes is accountable for aggravation of the disease and is associated with decreased overall survival. In this review, we present the pathogenesis of GvHD, with special focus on the special role of the gut microbiota and its crosstalk with immune cells. Moreover, we show the results of studies and case reports to date regarding the use of FMT in the treatment of steroid-resistant acute GvHD.

Trifluoromethylated Pyrazoles via Sequential (3 + 2)-Cycloaddition of Fluorinated Nitrile Imines with Chalcones and Solvent-Dependent Deacylative Oxidation Reactions

A general approach for preparation of two types of polyfunctionalized 3-trifluoromethylpyrazoles is reported. The protocol comprises (3 + 2)-cycloaddition of the in situ generated trifluoroacetonitrile imines with enones leading to trans-configured 5-acyl-pyrazolines in a fully regio- and diastereoselective manner. Initially formed cycloadducts were aromatized by treatment with manganese dioxide. Depending on the solvent used, the oxidation step either led to fully substituted pyrazoles (DMSO) or proceeded via a deacylative pathway to afford 1,3,4-trisubstituted derivatives (hexane) with excellent selectivity.

Synthesis and Cytotoxic Activity of Lepidilines A-D: Comparison with Some 4,5-Diphenyl Analogues and Related Imidazole-2-thiones

A straightforward access to 2-unsubstituted imidazole N-oxides with subsequent deoxygenation by treatment with Raney-nickel followed by N-benzylation opens up a convenient route to lepidilines A and C. Both imidazolium salts were used to generate in situ the corresponding imidazol-2-ylidenes, which smoothly reacted with elemental sulfur, yielding imidazole-2-thiones. These reactions were performed either under classical conditions in pyridine solutions or mechanochemically using solid Cs2CO3 as a base. The structure of lepidiline C was unambiguously confirmed by X-ray analysis of its hexafluorophosphate. An analogous protocol toward lepidilines B and D and their 4,5-diphenyl analogues is less efficient due to observed instability of the key precursors, i.e., the respective 2-methylimidazole N-oxides. Comparison of cytotoxic activity against HL-60 and MCF-7 cell lines of all lepidilines, as well as their selected structural analogues (e.g., 4,5-diphenyl derivatives and PF6 salts), revealed slightly more potent activity of the 2-methylated series, irrespectively of the type of counterion present in the imidazolium salt. Remarkably, the well-known 1,3-diadamantylimidazolium bromide (the "Arduengo salt"), known as the precursor of the first, shelf-stable NHC representative, and its adamantyloxy analogue displayed the most significant cytotoxic activity in the studied series.

The Role of the Gut Microbiome in Pathogenesis, Biology, and Treatment of Plasma Cell Dyscrasias

In response to emerging discoveries, questions are mounting as to what factors are responsible for the progression of plasma cell dyscrasias and what determines responsiveness to treatment in individual patients. Recent findings have shown close interaction between the gut microbiota and multiple myeloma cells. For instance, that malignant cells shape the composition of the gut microbiota. We discuss the role of the gut microbiota in (i) the development and progression of plasma cell dyscrasias, and (ii) the response to treatment of multiple myeloma and highlight faecal microbiota transplantation as a procedure that could modify the risk of progression or sensitize refractory malignancy to immunotherapy.

Resistin levels in perivascular adipose tissue and mid-term mortality in patients undergoing coronary artery bypass grafting

Higher serum resistin levels were reported to be associated with increased mortality risk. We aimed to assess the predictive value of resistin levels in perivascular adipose tissue (PVAT) around the left main coronary artery (LMCA) for mid-term survival of patients with advanced coronary artery disease (CAD).This was a prospective study including patients referred for elective coronary artery grafting in 2016 and 2017, performed using a standard approach. A sample of PVAT was harvested and resistin levels were measured using an enzyme-linked immunosorbent assay. Patients were followed from the day of the procedure until March 2021. In each patient, the SYNTAX score and EuroSCORE II were calculated. The study included 108 patients aged 68.1 ±7.9 years, including 83 men (76.9%). The duration of follow-up was 731 (range, 275-1020) for nonsurvivors and 1418 median (range, 1174-1559) for survivors (p <0.001). Patients who died had a higher SYNTAX score, higher EuroSCORE II, and lower resistin levels in PVAT than survivors (p <0.001, p = 0.004, and p = 0.041, respectively). A stepwise regression analysis revealed that survival was related to resistin concentrations above the median value (hazard ratio [HR], 4.67; 95% CI, 1.02-21.4; p = 0.048) and EuroSCORE II (used as continuous variable; HR, 1.55; 95% CI, 1.16-2.07; p = 0.003). The mid-term mortality in patients with advanced CAD is associated with low resistin concentrations in PVAT surrounding the LMCA.

A straightforward conversion of 1,4-quinones into polycyclic pyrazoles via [3 + 2]-cycloaddition with fluorinated nitrile imines

In-situ-generated N-aryl nitrile imines derived from trifluoroacetonitrile efficiently react with polycyclic 1,4-quinones, yielding fused pyrazole derivatives as the exclusive products. The reactions proceed via the initially formed [3 + 2]-cycloadducts, which undergo spontaneous aerial oxidation to give aromatized heterocyclic products. Only for 2,3,5,6-tetramethyl-1,4-benzoquinone, the expected [3 + 2]-cycloadduct exhibited fair stability and could be isolated in moderate yield (53%). The presented method offers a straightforward access to hitherto little known trifluoromethylated polycyclic pyrazoles. All products were isolated as pale colored solids with medium-intensity absorption maxima in the range of 310-340 nm for naphthoquinone-derived products and low-intensity bands in the visible region (≈400 nm) for the anthraquinone series.

Perspectives for the Use of CAR-T Cells for the Treatment of Multiple Myeloma

During recent years considerable progress has been made in the treatment of multiple myeloma. However, despite the current improvements in the prognosis of this malignancy, it always ends with relapse, and therefore new therapy approaches for destroying resistant cancer cells are needed. Presently, there is great hope being placed in the use of immunotherapy against refractory/relapsed multiple myeloma which is unresponsive to any other currently known drugs. The most promising one is CAR-T cell therapy which has already shown tremendous success in treating other malignancies such as acute lymphoblastic leukaemia (ALL) and could potentially be administered to multiple myeloma patients. CAR-T cells equipped with receptors against BCMA (B-cell maturation antigen), which is a surface antigen that is highly expressed on malignant cells, are now of great interest in this field with significant results in clinical trials. Furthermore, CAR-T cells with other receptors and combinations of different strategies are being intensively studied. However, even with CAR-T cell therapy, the majority of patients eventually relapse, which is the greatest limitation of this therapy. Serious adverse events such as cytokine release syndrome or neurotoxicity should also be considered as possible side effects of CAR-T cell therapy. Here, we discuss the results of CAR-T cell therapy in the treatment of multiple myeloma, where we describe its main advantages and disadvantages. Additionally, we also describe the current results that have been obtained on using combinations of CAR-T cell therapies with other drugs for the treatment of multiple myeloma.

Revealing biophysical properties of KfrA-type proteins as a novel class of cytoskeletal, coiled-coil plasmid-encoded proteins

Background

DNA binding KfrA-type proteins of broad-host-range bacterial plasmids belonging to IncP-1 and IncU incompatibility groups are characterized by globular N-terminal head domains and long alpha-helical coiled-coil tails. They have been shown to act as transcriptional auto-regulators.

Results

This study was focused on two members of the growing family of KfrA-type proteins encoded by the broad-host-range plasmids, R751 of IncP-1β and RA3 of IncU groups. Comparative in vitro and in silico studies on KfrA_R751 and KfrA_RA3 confirmed their similar biophysical properties despite low conservation of the amino acid sequences. They form a wide range of oligomeric forms in vitro and, in the presence of their cognate DNA binding sites, they polymerize into the higher order filaments visualized as “threads” by negative staining electron microscopy. The studies revealed also temperature-dependent changes in the coiled-coil segment of KfrA proteins that is involved in the stabilization of dimers required for DNA interactions.

Conclusion

KfrA_R751 and KfrA_RA3 are structural homologues. We postulate that KfrA type proteins have moonlighting activity. They not only act as transcriptional auto-regulators but form cytoskeletal structures, which might facilitate plasmid DNA delivery and positioning in the cells before cell division, involving thermal energy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-020-02079-w.

Tissue clearing-based method for unobstructed three-dimensional imaging of mouse penis with subcellular resolution

Although mice are widely used to elucidate factors contributing to penile disorders and develop treatment options, quantification of tissue changes upon intervention is either limited to minuscule tissue volume (histology) or acquired with limited spatial resolution (MRI/CT). Thus, imaging method suitable for expeditious acquisition of the entire mouse penis with subcellular resolution is described that relies on both aqueous- (clear, unobstructed brain imaging cocktails and computational analysis) and solvent-based (fluorescence-preserving capability imaging of solvent-cleared organs) tissue optical clearing (TOC). The combined TOC approach allows to image mouse penis innervation and vasculature with unprecedented detail and, for the first time, reveals the three-dimensional structure of murine penis fibrocartilage.

The [4+2]-Cycloaddition of α-Nitrosoalkenes with Thiochalcones as a Prototype of Periselective Hetero-Diels-Alder Reactions-Experimental and Computational Studies

The [4+2]-cycloadditions of α-nitrosoalkenes with thiochalcones occur with high selectivity at the thioketone moiety of the dienophile providing styryl-substituted 4H-1,5,2-oxathiazines in moderate to good yields. Of the eight conceivable hetero-Diels-Alder adducts only this isomer was observed, thus a prototype of a highly periselective and regioselective cycloaddition has been identified. Analysis of crude product mixtures revealed that the α-nitrosoalkene also adds competitively to the thioketone moiety of the thiochalcone dimer affording bis-heterocyclic [4+2]-cycloadducts. The experiments are supported by high-level DFT calculations that were also extended to related hetero-Diels-Alder reactions of other nitroso compounds and thioketones. These calculations reveal that the title cycloadditions are kinetically controlled processes confirming the role of thioketones as superdienophiles. The computational study was also applied to the experimentally studied thiochalcone dimerization, and showed that the 1,2-dithiin and 2H-thiopyran isomers are in equilibrium with the monomer. Again, the DFT calculations indicate kinetic control of this process.

2-Unsubstituted Imidazole N-Oxides as Novel Precursors of Chiral 3-Alkoxyimidazol-2-ylidenes Derived from trans-1,2-Diaminocyclohexane and Other Chiral Amino Compounds

‘Desymmetrization’ of trans-1,2-diaminocyclohexane by treatment with α,ω-dihalogenated alkylation reagents leads to mono-NH₂ derivatives (‘primary-tertiary diamines’). Upon reaction with formaldehyde, these products formed monomeric formaldimines. Subsequently, reactions of the formaldimines with α-hydroxyiminoketones led to the corresponding 2-unsubstituted imidazole N-oxide derivatives, which were used here as new substrates for the in situ generation of chiral imidazol-2-ylidenes. Upon O-selective benzylation, new chiral imidazolium salts were obtained, which were deprotonated by treatment with triethylamine in the presence of elemental sulfur. Under these conditions, the intermediate imidazol-2-ylidenes were trapped by elemental sulfur, yielding the corresponding chiral non-enolizable imidazole-2-thiones in good yields. Analogous reaction sequences, starting with imidazole N-oxides derived from enantiopure primary amines, amino alcohols, and amino acids, leading to the corresponding 3-alkoxyimidazole-2-thiones were also studied.

Synthesis and selected transformations of 2-unsubstituted 1-(adamantyloxy)imidazole 3-oxides: straightforward access to non-symmetric 1,3-dialkoxyimidazolium salts

Adamantyloxyamine reacts with formaldehyde to give N-(adamantyloxy)formaldimine as a room-temperature-stable compound that exists in solution in monomeric form. This product was used for reactions with α-hydroxyiminoketones leading to a new class of 2-unsubstituted imidazole 3-oxides bearing the adamantyloxy substituent at N(1). Their reactions with 2,2,4,4-tetramethylcyclobutane-1,3-dithione or with acetic acid anhydride occurred analogously to those of 1-alkylimidazole 3-oxides to give imidazol-2-thiones and imidazol-2-ones, respectively. Treatment of 1-(adamantyloxy)imidazole 3-oxides with Raney-Ni afforded the corresponding imidazole derivatives without cleavage of the N(1)–O bond. Finally, the O-alkylation reactions of the new imidazole N-oxides with 1-bromopentane or 1-bromododecane open access to diversely substituted, non-symmetric 1,3-dialkoxyimidazolium salts. Adamantyloxyamine reacts with glyoxal and formaldehyde in the presence of hydrobromic acid yielding symmetric 1,3-di(adamantyloxy)-1H-imidazolium bromide in good yield. Deprotonation of the latter with triethylamine in the presence of elemental sulfur allows the in situ generation of the corresponding imidazol-2-ylidene, which traps elemental sulfur yielding a 1,3-dihydro-2H-imidazole-2-thione as the final product.

Polysubstituted 3-trifluoromethylpyrazoles: regioselective (3 + 2)-cycloaddition of trifluoroacetonitrile imines with enol ethers and functional group transformations

Non-catalysed addition of trifluoroacetonitrile imines to enol ethers provided fully regioselectively (3 + 2)-cycloadducts, which either spontaneously or via Brønsted acid-induced elimination of ROH molecules led to the formation of 3-trifluoromethylated pyrazoles. In the case of 2,3-dihydrofuran, the respective bicyclic intermediate was isolated and its structure was confirmed by X-ray analysis. Using the developed protocol the synthesis of a known antitumor compound SC-560 was performed in 45% yield. Subsequent functionalisations of selected 4-(ω-hydroxyalkyl)pyrazoles at C(5) through lithiation/addition, cross-coupling reactions or via intramolecular Pd-catalysed C-H arylations opened up an access to polysubstituted pyrazoles including unusual tricyclic systems comprising 7-membered rings (oxepane, thiepane and azepane) as the central unit.

A Straightforward Access to Trifluoromethylated Spirobipyrazolines through a Double (3+2)-Cycloaddition of Fluorinated Nitrile Imines with Alkoxyallenes

Formal double (3+2)-cycloaddition of in situ generated tri­fluoroacetonitrile imines with alkoxyallenes proceeds in a highly regio- and diastereoselective manner to afford anti-configured spirobipyrazolines as the exclusive 2:1 adducts. Initial stepwise addition of the title electron-deficient 1,3-dipoles onto cumulenic reaction partner is pos­tulated to explain the observed reaction pathway.

The first organocatalytic, ortho-regioselective inverse-electron-demand hetero-Diels–Alder reaction

The development of the unprecedented ortho-regioselective inverse-electron-demand hetero-Diels–Alder (IEDHDA) reaction is described.

Medical students’ perceptions of people with disabilities

Introduction: Little is known about associations of attitudes of medical students towards people with disabilities and their life satisfaction and empathy. Purpose: To assess the social perception of people with disabilities by medical students. Materials and methods: The present study interviewed 451 medical students of the Medical University of Białystok regarding their perceptions of people with disabilities, especially in light of their own satisfaction with life and empathy. We used the following questionnaires: the original questionnaire about attitudes towards people with disabilities, The Satisfaction with Life Scale (SWLS), and Empathy Understanding Questionnaire (KRE). Results: Attitudes towards people with disabilities people were generally positive. Almost 40% of respondents expressed a willingness to help for people with disabilities. In general, disabled people do not have full access to all fields of social (63.4%) and professional (63.2%) life. At the same time, disabled people tend to marry (84.9%), have children (82.1%), work (88.2%), and drive cars (76.1%). Respondents were convinced that contact with a disabled person teaches ways to help others (42.1%), and in fact 58.6% of respondents reported having decided to participate with helping the disabled. The average life satisfaction of the students was 22.7 ± 5.3 which indicates that the respondents are satisfied with their lives. The empathy level of respondents was 66.97 points ± 2.98, which indicates average level of empathy. Conclusions: This study shows that students’ perception of people with disabilities depends upon how the students viewed disabled people’s, life satisfaction and empathy.

Induction of smectic polymorphism in bent-core derivatives of the 6-oxoverdazyl by partial fluorination of alkyl chains

A series of bent-core mesogens 2[m,n] derived from the 6-oxoverdazyl radical and containing partially fluorinated alkyl tails was prepared and investigated by thermal, optical, XRD and EPR methods.

Synthesis of Sulfur-Rich Crown Ethers via Azide–Alkyne Macrocyclization of α,ω-Diazido- and α,ω-Dipropargyl Sulfide Derivatives

A series of diazides and dithiols were prepared in a one-pot protocol from commercially available alcohols by a modified Appel reaction. Selected dithiols were converted into α,ω-dipropargyl sulfides and combined with thioglycol-derived diazides under Huisgen–Sharpless–Meldal reaction conditions to give a new class of 1,2,3-triazole-linked sulfur-rich crown ethers.

3-Substituted 6-oxoverdazyl bent-core nematic radicals: synthesis and characterization

Bent-core mesogens containing the 6-oxoverdazyl as the central angular unit exhibit rare nematic behavior.

[Keto acidosis and coma in 44-years old man with diabetes t1 in Internal Diseases Department in Dabrowa Tarnowska]

Diabetic ketoacidosis (DKA) is an acute complication metabolic occur- ring in patients with diabetes type-1 and much less likely to type 2 diabetes. This article shows clinical manifesta- tion, biochemical criteria and algorithm for the immediate assessment and management of diabetic acidosis in a 44 years old men. This specification describes a rare case of keto acidosis and coma therapy and the challenges that these disorders carry.