[Acute Traumatic Intervertebral Disc Herniation]. / Akutní traumatická hernie intervertebrálního disku.

Acute traumatic intervertebral disc herniation of the thoracic spine is a rather rare injury with only a few reported cases to date. In this manuscript, we present a case of a 58-year-old male patient who sustained a car accident-related high-energy trauma, resulting in a disc herniation of the thoracic spine. Furthermore, we also discuss the possible implications of late diagnosis of such condition. The patient was initially referred from the Emergency Department as a case of head contusion with a left upper limb paresis. Due to only minimal bony trauma visible on the initial spine CT scan, the neurological deficit was attributed to the cranial trauma. The diagnosis of a traumatic disc herniation was therefore established only after the rapid onset of paraparesis, which gradually progressed into paraplegia, and a following spine MRI scan. Despite the subsequent urgent spinal decompression, the neurological functions of the lower limbs were not restored. This manuscript addresses the indications for performing MRI scans in polytrauma patients with a CT-verified spine trauma. Although it may be complicated to perform routine MRI scans in all such patients in daily practice, it can certainly help diagnose such injuries earlier and thus prevent potential permanent neurological damage to the patients. Key word: spine injury, traumatic disc herniation, thoracic spine, spine surgery.

[Use of Solid Intercalary Allografts for Reconstruction Following the Resection of Primary Bone Tumors]. / Vyuzití solidních interkalárních allostepu k rekonstrukci po resekcích primárních kostních nádoru.

PURPOSE OF THE STUDY There are several treatment options for bone tumors at diaphyseal/metadiaphyseal sites of long bones (with joint preservation) including massive intercalary allografts, autografts (vascularized or non-vascularized fibular autograft, devitalised tumor bearing bone), endoprosthetic replacement (intercalary spacer), cementoplasty with ostheosynthesis and distraction osteogenesis. Reconstruction using massive intercalary bone allografts is for us the method of choice in case of curable primary bone tumors at the diaphyseal/metadiaphyseal region. The purpose of this study is to evaluate our results and complications. MATERIAL AND METHODS Our retrospective study reviewed 41 patients after intercalary allograft reconstruction following the resection of primary bone tumors in the years 2000 - 2014. The group consists of 27 men and 14 women with the mean age at the time of diagnosis 27 years and the mean follow-up (from primary surgery) was 7 years. The patients were diagnosed with the Ewing sarcoma (14), chondrosarcoma (9), osteosarcoma (8), adamantinoma (6), OFD-like adamantinoma (2) and aneurysmatic bone cyst (2). The site of tumor were tibia (18), femur (16), humerus (5), radius (1) and ulna (1). We retrospectively evaluated the results of this intercallary allograft reconstructions, the incidence of failures and complications as well as the role of risk factors. RESULTS 14 patients (34.1%) successfully healed without complications. In the same number of patients (14 patients, 34.1%) the allograft reconstruction failed. 7 of these patients underwent amputation (17.1%), 6 of whom for oncological complications (local recurrence) and only 1 for complications of the reconstruction (infection). Other 7 patients with an allograft-related failure were successfully treated with a limb salvage procedure and underwent a new reconstruction. The remaining 13 patients (31.7%) suffered from complications that did not result in a failure of the reconstruction. The major complications of the reconstruction were the non-union (53.7%), fractures and allograft resorption (14.6%) and infection (7.3%). By statistical evaluation of common risk factors a statistically significant relationship was found between uncomplicated healing and stable bridging osteosynthesis (p = 0.014), between allograft fractures/resorptions and non-bridging osteosynthesis (p = 0.018), and the lowest reoperation rate was connected with plate osteosynthesis (0.037). DISCUSSION AND CONCLUSIONS The intercalary allograft reconstruction is an important biological method in orthopaedic tumor surgery. Even though it is connected with a high rate of complications (non-union, fracture and resorption, infection), in the vast majority of cases they can be solved, while achieving limb-salvage and good function of extremity. The essential prerequisite for successful uncomplicated healing of reconstruction is the stable bridging osteosynthesis, preferably with a plate. In high risk patients with a combination of recognized important risk factors described in literature (adult patients, large resection (more than 15 cm), femoral location and aggressive oncological treatment) we nowadays try to reduce the complication rate with a primary combination of an allograft with vascularized fibular autograft. Key words:biological bone reconstruction, massive intercallary allograft, stable bridging osteosynthesis, primary bone tumors.

[Overview of primary sternal closure techniques]. / Prehled metod primárního uzáveru strední sternotomie.

The aim of the overview study is to describe the currently used methods of primary median sternotomy closure in adult cardiac surgery. In the review of published literature, we draw on the data and focus on the methodology, indications, advantages, limitations, biomechanical and clinical results of the different methods in relation to the incidence of deep sternal wound complications after median sternotomy in adult cardiac surgery.Key words: sternum sternotomy adult cardiac surgery surgical procedures.

Maternal-Fetal Microchimerism: Impacts on Offspring's Immune Development and Transgenerational Immune Memory Transfer.

Maternal-fetal microchimerism is a fascinating phenomenon in which maternal cells migrate to the tissues of the offspring during both pregnancy and breastfeeding. These cells primarily consist of leukocytes and stem cells. Remarkably, these maternal cells possess functional potential in the offspring and play a significant role in shaping their immune system development. T lymphocytes, a cell population mainly found in various tissues of the offspring, have been identified as the major cell type derived from maternal microchimerism. These T lymphocytes not only exert effector functions but also influence the development of the offspring's T lymphocytes in the thymus and the maturation of B lymphocytes in the lymph nodes. Furthermore, the migration of maternal leukocytes also facilitates the transfer of immune memory across generations. Maternal microchimerism has also been observed to address immunodeficiencies in the offspring. This review article focuses on investigating the impact of maternal cells transported within maternal microchimerism on the immune system development of the offspring, as well as elucidating the effector functions of maternal cells that migrate through the placenta and breast milk to reach the offspring.

Disease-Associated Variants in GRIN1, GRIN2A and GRIN2B genes: Insights into NMDA Receptor Structure, Function, and Pathophysiology.

N-methyl-D-aspartate receptors (NMDARs) are a subtype of ionotropic glutamate receptors critical for synaptic transmission and plasticity, and for the development of neural circuits. Rare or de-novo variants in GRIN genes encoding NMDAR subunits have been associated with neurodevelopmental disorders characterized by intellectual disability, developmental delay, autism, schizophrenia, or epilepsy. In recent years, some disease-associated variants in GRIN genes have been characterized using recombinant receptors expressed in non-neuronal cells, and a few variants have also been studied in neuronal preparations or animal models. Here we review the current literature on the functional evaluation of human disease-associated variants in GRIN1, GRIN2A and GRIN2B genes at all levels of analysis. Focusing on the impact of different patient variants at the level of receptor function, we discuss effects on receptor agonist and co-agonist affinity, channel open probability, and receptor cell surface expression. We consider how such receptor-level functional information may be used to classify variants as gain-of-function or loss-of-function, and discuss the limitations of this classification at the synaptic, cellular, or system level. Together this work by many laboratories worldwide yields valuable insights into NMDAR structure and function, and represents significant progress in the effort to understand and treat GRIN disorders. Keywords: NMDA receptor , GRIN genes, Genetic variants, Electrophysiology, Synapse, Animal models.

[30 years of liver transplants in Brno]. / 30 let transplantace jater v Brne

On 3 February 1983 the first successful liver transplant in Czechoslovakia took place at the 2nd Surgery Clinic in Brno. This operation was preceded by 14 years of experiments, including more than 150 orthotopic liver transplants in pigs. Josef Mynár, a patient who suffered from an extensive liver tumour -  hepatoma -  has been living ever since, i.e. for 30 years after the transplant, leading a very active life in a good health condition.

Non-coaxial deformation of foreland basement involved in a fold-and-thrust belt: a strain partitioning approach to the Eastern Variscan orogen.

The general SW-NE course of the Variscan orogen in Europe is abruptly bent to the N-S course at its eastern margin, where an oblique convergence occurred. The main suture in this part of the Variscan orogenic belt is called the Moldanubian Thrust, characterized by a dominant dextral strike-slip kinematics and a minor thrust component. The deep level of erosion and the good exposure of this structure allowed us to study the mechanisms of oblique convergence and the incorporation of the foreland basement into the orogenic belt. The combination of small-scale structures with the anisotropy of magnetic susceptibility studies allowed the recognition of two deformations in the studied rocks: dextral simple shearing and drag folding. Due to oblique convergence, the deformations induced by this mechanism were non-coaxial; therefore, their contributions can be easily distinguished. Finally, an overturned, almost recumbent large-scale synformal fold structure in the footwall and an antiformal structure in the hanging wall of the Moldanubian Thrust were formed. These two folds can be interpreted as structures formed by dragging along the Moldanubian Thrust. The previously described sinistral simple shearing in the upper limb of the synform resulted from the original dextral strike-slip shearing, which was overturned during progressive deformation.

[Analysis of prognostic factors in osteosarcoma adult patients, a single institution experience]. / Prognostické faktory konvencního osteosarkomu dospelých pacientu

BACKGROUND: The objective of this report was to estimate long-term outcome and prognostic factors in adult patients with high-grade osteosarcoma. The intended therapeutic strategy included preoperative and/or postoperative chemotherapy as well as surgery of all operable lesions. PATIENTS AND METHODS: We reviewed the clinical data of 36 newly diagnosed adult patients (aged 19-82, average 37.5, median 28.5 years) with high-grade osteosarcoma of the trunk or limbs evaluated by a multidisciplinary team and treated between 1999 and 2010 in Brno. Forty-five percent of patients were over thirty, more than 36% over forty. Thirty-one percent of patients had metastasis at the time of diagnosis. Demographic parameters, tumor-related and treatment-related variables included possible prognostic factors and their impact on response, overall survival (OS) and event-free survival (EFS) were analyzed. RESULTS: All the patients were followed up after treatment. Seventy-three percent of patients were poor responders to chemotherapy. Sixteen patients are alive, and twenty patients died. The survival time ranged from 2 to 177 months (average 45 months, median survival 23 months). The 5-year OS of all patients was 52.4%. OS of patients without metastasis was 68.12%, while 2-year OS with metastasis was 26% only. 5-year EFS was 38.7%. Univariate analysis revealed that the prognosis of adult osteosarcoma patients was significantly related to distant metastasis (p = 0.006), surgical stage (p = 0.00582), serum alkaline phosphatase (ALP) level (p = 0.00841) and serum lactatdehydrogenase (LD) level (p = 0.047). The other analyzed prognostic factors including age had no statistically significant influence on outcome of osteosarcoma in adult patients. CONCLUSION: The prognosis of osteosarcoma in adult patients was significantly correlated to surgical stage, distant metastasis, serum ALP and LD.

Development of the Lie-to-Sit-to-Stand-to-Walk Transfer (LSSWT) test for early mobilization in older patients in geriatric rehabilitation.

BACKGROUND: Early discharge from a rehabilitation center is only possible, if patients are able to do basic transfers independently (e.g., get up from bed and walk to the toilet). Against this background, the Lie-to-Sit-to-Stand-to-Walk Transfer (LSSWT) test was developed in order to quantify complex transfer abilities in older adults. This study was to evaluate the reliability and validity of this instrument. MATERIAL AND METHODS: A total of 24 older patients (80.25±8.10 years) of a geriatric rehabilitation unit performed the LSSWT test. Expert ratings were used to measure criterion validity. The Timed Up & Go test (TUG) was administered to assess construct validity. Furthermore, the time score of the LSSWT test was correlated with the Trunk Control Test (TCT), balance performance, the Chair Stand Test (CST) and gait speed. Intra- and interrater reliability were measured, conducting the LSSWT test on consecutive days. RESULTS: The coefficients of correlation between the LSSWT test and the expert ratings as well as the TUG test were r=-0.82 and r=0.83, respectively. Furthermore, the association with the TCT, balance, CST, and gait speed were r=-0.51, r=-0.45, r=0.47, and r=-0.72, respectively. The results of intrarater reliability and interrater reliability were ICC=0.96 and ICC=0.77, respectively. CONCLUSION: The study shows that the LSSWT test is a valid measure for quantifying difficulties in transfer abilities of patients during geriatric rehabilitation. The good correlation between LSSWT test and TUG test indicates good construct validity, but also that the LSSWT test provides additional information. Interrater reliability was moderate; therefore, the training of the supervisors should be re-evaluated. Further research is needed to establish cut-off values for discharge decision and to analyze the use of the LSSWT test in different subgroups.

Relative contribution of T and B cells to hypermutation and selection of the antibody repertoire in germinal centers of aged mice.

The immune system of aged individuals often produces antibodies that have lower affinity and are less protective than antibodies from young individuals. Recent studies in mice suggested that antibodies produced by old individuals may be encoded by distinct immunoglobulin (Ig) genes and that the somatic hypermutation process in these individuals is compromised. The present study employed Ighb scid mice reconstituted with normal lymphocytes from young (2-3-mo-old) and aged (20-25-mo-old) donors and immunized with a protein conjugate of the hapten (4-hydroxy-3-nitrophenyl)acetyl (NP) to determine whether the molecular changes in antibody repertoire reflect senescence in the B cells or whether they are mediated by the aging helper T lymphocytes. The NP-reactive B cells from splenic germinal centers (GC) were recovered by microdissection of frozen tissue sections and their rearranged Ig heavy chain variable region (VH) genes of the V186.2/V3 families were sequenced. It was found that the VH gene repertoire of the GC B cells was strongly influenced by the source of the CD4+ T cells. When T cells were donated by young mice, the anti-NP response in GC was dominated by the canonical V186.2 gene, even if the responder B cells came from aged donors. However, when the mice were reconstituted with T cells from aged donors, the expression of the V186.2 gene by young B cells was diminished and the response was dominated by the C1H4 gene, another member of the V186.2/V3 family. In contrast, the somatic hypermutation process in the GC B cells followed a different pattern. The mutation frequencies in the animals that were reconstituted with both B and T cells from young donors (1/50 to 1/150 bp) were comparable to the frequencies previously reported for NP-immunized intact young/adult mice. However, when either lymphocyte subset was donated by the aged mice, the mutation frequencies declined. Thus, mice reconstituted with T cells from the aged and B cells from the young had severely compromised mutational mechanism. Likewise, the recipients of aged B and young T cells had diminished mutations even though the repertoire of their anti-NP response was dominated by the canonical V186.2 gene. It appears that the change in germine-encoded repertoire and the decrease of somatic hypermutation represent distinct mechanisms of immunosenescence and that the aging of helper T cells plays a pivotal role in both of these processes.

Facultative role of germinal centers and T cells in the somatic diversification of IgVH genes.

The development of memory B cells takes place in germinal centers (GC) of lymphoid follicles where antigen-driven lymphocytes undergo somatic hypermutation and affinity selection, presumably under the influence of helper T cells. However, the mechanisms that drive this complex response are not well understood. We explored the relationship between GC formation and the onset of hypermutation in response to the hapten phosphorylcholine (PC) coupled to antigenic proteins in mice bearing different frequencies of CD4+ T cells. PC-reactive GC were identified by staining frozen splenic sections with peanut agglutinin (PNA) and with monoclonal Abs against AB1-2, a dominant idiotope of T15+ anti-PC antibody. The nucleotide sequences of rearranged T15 VH1 genes were determined from polymerase chain reaction amplifications of genomic DNA from microdissected GC B cells. T15+ GC became fully developed by day 6-7 after primary immunization of euthymic mice with either PC-keyhole limpet hemocyanin (KLH) or PC-chicken gamma globulin (CGG). Yet the VH1 gene segments recovered from the primary GC as late as day 10-14 had low numbers of mutations, in contrast to responses to the haptens nitrophenyl or oxazolone that sustain high levels of hypermutation after GC formation. PC-reactive B cells proliferate in histologically typical GC for considerable periods with no or little somatic hypermutation; the signals for GC formation are independent of those for the activation of hypermutation. We then examined GC 7 d after secondary immunization with PC-KLH in euthymic mice, in nu/nu mice reconstituted with limited numbers of normal CD4+ cells before priming (CD4(+)-nu/nu) and in nu/nu mice. All of these animals develop T15+ GC after antigen priming, however, the patterns of V gene mutations in the secondary GC reflected the levels of CD4+ cells present during the primary response. VDJ sequences from secondary GC of euthymic mice were heavily mutated, but most of these mutations were shared among all related (identical VDJ joints) sequences suggesting the proliferation of mutated, memory B cells, with little de novo somatic hypermutation. In contrast, the patterns of V gene diversity in secondary GC from CD4(+)-nu/nu mice suggested that there was ongoing mutation and clonal diversification during the first week after rechallenge. The secondary GC from T cell-deficient, nu/nu mice showed little evidence for mutational and/or recombinational diversity of T15+ B cells. We conclude that the participation of CD4+ helper cells is required for full activation of the mutator in GC and takes place in a dose-dependent fashion.

Thymic requirement for cyclical idiotypic and reciprocal anti-idiotypic immune responses to a T-independent antigen.

The role of the thymus in the cyclical appearance of the dominant idiotype of the myeloma protein secreted by the TEPC-15 plasmacytoma (T-15)-bearing plaque-forming cells (PFC) and anti-idiotypic cells (i.e., cells with receptors for T-15) in the spleen during a primary response to the phosphorylcholine determinant of Streptococcus pneumoniae, strain R36a (Pn) was studied using normal mice, thymus-deficient nude mice, and thymus gland-grafted nude mice (TG-nude). The nude mice and their phenotypically normal littermates (LM) were backcrossed on the BALB/c genetic background. The kinetics of the anti-Pn PFC response of BALB/c inbred mice, littermates of nude mice, and TG-nude mice were essentially the same. There was an initial peak on day 5-6 followed by a decline to near background, and then a second peak on day 12. In nude mice, the first peak of anti-Pn PFC (day 5) was comparable in magnitude to that of mice with an intact thymus; however, there was no second peak. In contrast to the cellular response measured at the level of PFC, the serum antibody response to Pn (assayed by passive hemagglutination of sheep erythrocytes coated with Pn polysaccharide) was comparable in all groups of mice and did not show a measurable oscillation. The anti-idiotypic cellular activity was determined by the ability of spleen cells to bind radiolabeled (125I) TEPC-15 myeloma protein (IgA, kappa) which carries an idiotypic determinant indistinguishable from that of most anti-phosphorylcholine antibodies in BALB/c mice. Binding of radiolabeled McPC-603 (IgA, kappa) and MOPC-315 (IgA, lambda 2) myeloma proteins (which lack the T-15 idiotypic determinant) served as controls. The changes in T-15 binding by splenic lymphocytes following the Pn immunization differed between normal and athymic mice. BALB/c, LM, and TG-nude mice showed a biphasic pattern with peaks at days 3--4 and 10--11 that was nearly reciprocal to the PFC curve. On the other hand, T-15 binding in nude mice either declined and remained depressed or was not affected by the ongoing anti-Pn response. These observations demonstrate that mature T cells are required for cyclical idiotypic and anti-idiotypic responses to immunization with a T-independent antigen and suggest that the cyclical immune response may result from an interaction between idiotypic and anti-idiotypic cell clones.

Induction of idiotype-specific suppressor T cells with antigen/antibody complexes.

The effects of immune complexes on the antibody response of BALB/c mice to Streptococcus pneumoniae R36a (Pn) were investigated. The cell wall polysaccharide (PnC) extracted from Pn was used to form complexes with TEPC-15, a myeloma protein that binds to phosphorylcholine determinants on the PnC. Complexes formed at equivalence were cultured with splenic T cells from BALB/c mice for 2 d, and then the cells were added to fresh BALB/c spleen cell cultures to test their effect on the antibody response to Pn, a response dominated by the T15 idiotype family. The results indicate that TEPC-15/PnC complexes induced potent suppressor T cells (Ts) whereas cells cultured with free antigen or free antibody alone had no effect on the plaque-forming cell response to Pn. The suppression was specific since the response to control antigens such as sheep erythrocytes was unaffected. The suppression appears to be idiotype-specific since the Ts had a relatively weak (and in some cases no) effect on the anti-Pn response of BALB/c mice that had been suppressed for T15 idiotopes by neonatal injection of a monoclonal anti-T15 antibody, MaId 5-4. Furthermore, cells cultured with TEPC-15/PnC complexes were shown to express specific receptors for TEPC-15 idiotopes. The results indicate that antigen/antibody complexes may have important immunoregulatory effects because they are potent inducers of idiotype-specific Ts.

Immunoglobulin idiotopes expressed by T cells. I. Expression of distinct idiotopes detected by monoclonal antibodies on antigen-specific suppressor T cells.

The idiotopic repertoire expressed by antigen-specific suppressor T cells (Ts) generated by Streptococcus pneumoniae strain R36a (Pn) in BALB/c strain mice was investigated using a panel of five monoclonal anti-idiotopic antibodies against TEPC-15/HOPC-8 myeloma proteins. Previous studies suggested that the anti-idiotopic antibodies recognize distinct idiotopic determinants within the T15 idiotype, and that Pn-reactive B cells express all of those idiotopes as shown by a specific inhibitory effect of the anti-idiotopic antibodies on induction of anti-Pn response in vitro as well as on the mature antibody plaque-forming cells. In this study we asked the question of whether anti-idiotopic (Id) can block the inductive and/or effector phases of generation of Ts which act on the Pn-reactive B cells. The presence of anti-Id during the activation of T cells with Pn did not prevent the generation of Ts. However, suppression mediated by Ts on responder lymphocytes (cultures of spleen cells or B cels) was inhibited (reversed) by four out of five anti-Id. Some of the antibodies recognize hapten (phosphorylcholine)-inhibitable Id in the paratope of Ig whereas others are directed against nonparatopic Id. These data indicate that the antigen receptor on Ts includes VH sequences both within and without the immunoglobulin in paratope, and that the Id repertoir of Ts overlaps with that of B cells.

Phosphoprotein associated with glycosphingolipid-enriched microdomains (PAG), a novel ubiquitously expressed transmembrane adaptor protein, binds the protein tyrosine kinase csk and is involved in regulation of T cell activation.

According to a recently proposed hypothesis, initiation of signal transduction via immunoreceptors depends on interactions of the engaged immunoreceptor with glycosphingolipid-enriched membrane microdomains (GEMs). In this study, we describe a novel GEM-associated transmembrane adaptor protein, termed phosphoprotein associated with GEMs (PAG). PAG comprises a short extracellular domain of 16 amino acids and a 397-amino acid cytoplasmic tail containing ten tyrosine residues that are likely phosphorylated by Src family kinases. In lymphoid cell lines and in resting peripheral blood alpha/beta T cells, PAG is expressed as a constitutively tyrosine-phosphorylated protein and binds the major negative regulator of Src kinases, the tyrosine kinase Csk. After activation of peripheral blood alpha/beta T cells, PAG becomes rapidly dephosphorylated and dissociates from Csk. Expression of PAG in COS cells results in recruitment of endogenous Csk, altered Src kinase activity, and impaired phosphorylation of Src-specific substrates. Moreover, overexpression of PAG in Jurkat cells downregulates T cell receptor-mediated activation of the transcription factor nuclear factor of activated T cells. These findings collectively suggest that in the absence of external stimuli, the PAG-Csk complex transmits negative regulatory signals and thus may help to keep resting T cells in a quiescent state.

[Persisting symptoms, diastolic dysfunction and decreased coronary flow reserve after succesful correction of aortic recoarctation]. / Pretrvávajúce symptómy, diastolická dysfunkcia a nízka koronárna rezerva u pacientky po úspesnej korekcii rekoarktácie aorty.

We present a case of a 53-year-old woman undergoing successful surgical treatment ofcoarcation restenosis after patch grafting in childhood. Despite the optimal result of the operation, normal left ventricle systolic function and coronary angiogram, majority of symptoms, such as angina and dyspnea, persist 16 months after the intervention. In further investigation, pathological values of left ventricular end-diastolic pressure (LVEDP = 30 mm Hg) and coronary flow reserve (CFR = 1.3) were confirmed, implicating recoarctation to be the unusual cause of cardiac syndrome X.

[Surgical management of the abdominal aortic aneurysm in a patient with left-sided inferior vena cava and a functional solitary left kidney]. / Chirurgické resní aneuryzmatu abdominální aorty u pacientky s levostrannou dolní dutou zilou a funkcne solitárni levou ledvinou.

In a polymorbid female patient, an aneurysm of the abdominal aorta was discovered incidentally, necessitating admission to an angiosurgical department. On surgery, an additional problem was found, the left-sided inferior vena cava (a congenital anomaly of the venous system) as well as the juxtarenal aneurysm of the abdominal aorta. As the patient had a solitary functioning kidney, the resection of the aortic aneurysm was considered to be associated with unacceptable risk if performed at a standard department. Therefore, the patient was transferred to the Centre of Cardiovascular Surgery and Transplantations Brno where a resection of the aneurysm was performed. On resection, the perfusion of the solitary functioning kidney was maintained with organ preservation solution used in organ transplantations. The operation was uneventful, the postoperative course was complicated only by insignificant wound healing problems.

COVID-19 and the immune system.

A close interaction between the virus SARS-CoV-2 and the immune system of an individual results in a diverse clinical manifestation of the COVID-19 disease. While adaptive immune responses are essential for SARS-CoV-2 virus clearance, the innate immune cells, such as macrophages, may contribute, in some cases, to the disease progression. Macrophages have shown a significant production of IL-6, suggesting they may contribute to the excessive inflammation in COVID-19 disease. Macrophage Activation Syndrome may further explain the high serum levels of CRP, which are normally lacking in viral infections. In adaptive immune responses, it has been revealed that cytotoxic CD8+ T cells exhibit functional exhaustion patterns, such as the expression of NKG2A, PD-1, and TIM-3. Since SARS-CoV-2 restrains antigen presentation by downregulating MHC class I and II molecules and, therefore, inhibits the T cell-mediated immune responses, humoral immune responses also play a substantial role. Specific IgA response appears to be stronger and more persistent than the IgM response. Moreover, IgM and IgG antibodies show similar dynamics in COVID-19 disease.

Expression and distribution of CD151 as a partner of alpha6 integrin in male germ cells.

The physiological importance of CD151 tetraspanin is known from somatic cells and its outside-in signalling through integrins was described. In male germ cells, two tetraspanins, CD9 and CD81, are involved in sperm-egg membrane fusion, and similarly to integrins, they occupy characteristic regions. We report here on a newly discovered presence of CD151 in sperm, and present its expression and distribution during spermatogenesis and sperm transition during the acrosome reaction. We traced CD151 gene and protein expression in testicular cell subpopulations, with strong enrichment in spermatogonia and spermatids. The testicular and epididymal localization pattern is designated to the sperm head primary fusion site called the equatorial segment and when compared to the acrosome vesicle status, CD151 was located into the inner acrosomal membrane overlying the nucleus. Moreover, we show CD151 interaction with α6 integrin subunit, which forms a dimer with ß4 as a part of cis-protein interactions within sperm prior to gamete fusion. We used mammalian species with distinct sperm morphology and sperm maturation such as mouse and bull and compared the results with human. In conclusion, the delivered findings characterise CD151 as a novel sperm tetraspanin network member and provide knowledge on its physiology in male germ cells.

Pre-Transplant Marital Status and Hematopoietic Cell Transplantation Outcomes

Background: Evidence about the impact of marital status before hematopoietic cell transplantation (hct) on outcomes after hct is conflicting. Methods: We identified patients 40 years of age and older within the Center for International Blood and Marrow Transplant Research registry who underwent hct between January 2008 and December 2015. Marital status before hct was declared as one of: married or living with a partner, single (never married), separated or divorced, and widowed. We performed a multivariable analysis to determine the association of marital status with outcomes after hct. Results: We identified 10,226 allogeneic and 5714 autologous hct cases with, respectively, a median follow-up of 37 months (range: 1-102 months) and 40 months (range: 1-106 months). No association between marital status and overall survival was observed in either the allogeneic (p = 0.58) or autologous (p = 0.17) setting. However, marital status was associated with grades 2-4 acute graft-versus-host disease (gvhd), p < 0.001, and chronic gvhd, p = 0.04. The risk of grades 2-4 acute gvhd was increased in separated compared with married patients [hazard ratio (hr): 1.13; 95% confidence interval (ci): 1.03 to 1.24], and single patients had a reduced risk of grades 2-4 acute gvhd (hr: 0.87; 95% ci: 0.77 to 0.98). The risk of chronic gvhd was lower in widowed compared with married patients (hr: 0.82; 95% ci: 0.67 to 0.99). Conclusions: Overall survival after hct is not influenced by marital status, but associations were evident between marital status and grades 2-4 acute and chronic gvhd. To better appreciate the effects of marital status and social support, future research should consider using validated scales to measure social support and patient and caregiver reports of caregiver commitment, and to assess health-related quality of life together with health care utilization.