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Pflügers Archiv (2022). doi:10.1007/s00424-022-02781-w, Published by Springer, Berlin ; Heidelberg

Background: Synchronous endometrial and ovarian cancer (SEOC) accounts for 50-70% of all synchronous gynecology cancers in women. Approximately 14% of SEOC cases are caused by Lynch syndrome (LS). The widespread introduction of "universal screening" at LS (all cases with CRC and all EC cases diagnosed before age 60 should be tested for MMR deficiency) has led to an increasing number of suspected LS cases- MMR-deficient tumors without germline mutation in the MMR genes. These cases are attributed to the so-called Lynch-like syndrome (LLS). Case presentation: We present a case of LLS with a detected germline, likely pathogenic variant in the WRN gene. The proband was a woman diagnosed with SEOC at the age of 51 years. Histology of both tumors (endometrium and ovary) was endometroid and showed loss of MLH1 and PMS protein expression. Genetic testing by next generation sequencing (NGS) detected a germline mutation (in the heterozygous state) in the WRN gene - c.4109del, p.(Asn1370ThrfsTer23) in the proband. Conclusions: The presented case contributes to the etiology of LLS and confirms the need for specific genetic testing, together with genetic counseling, in hereditary cancer syndromes. The use of combined information from clinicians, pathologists, genetic counselors, and data from NGS testing for cancer predisposition, clinical surveillance, and follow-up management in women with gynecology cancers, especially SEOC, could be improved.

Changes in the expression of non-coding ribonucleic acids (ncRNAs) takes part in the formation of various tumors. Multiple endocrine neoplasia syndrome type 1 (MEN1) is a rare autosomal dominant disease caused by mutations of the MEN1 gene encoding the Menin protein. Syndrome is characterized by the occurrence of parathyroid tumors, gastroenteropancreatic neuroendocrine tumors, pituitary adenoma, as well as other endocrine and non-endocrine tumors. The mechanisms for the formation of MEN1-related tumors due to mutations in the MEN1 gene are not . In the absence of mutations of the MEN1 gene in patients with phenotypically similar features, this condition is regarded as a phenocopy of this syndrome. The cause of the combination of several MEN-1-related tumors in these patients remains unknown. The possible cause is that changes in the expression of ncRNAs affect the regulation of signaling pathways in which Menin participates and may contribute to the development of MEN-1-related tumors. The identification of even a small number of agents interacting with Menin makes a significant contribution to the improvement of knowledge about its pathophysiological influence and ways of developing tumors within the MEN-1 syndrome and its phenocopies.

Diabetes mellitus (DM) is a significant predictor of atherosclerosis, cardiovascular disease, and cardiovascular mortality. It is known that atherosclerosis occurs earlier in patients with diabetes, reducing the duration of their life. Leptin as well as other inflammatory markers can contribute to the progression of atherosclerosis in patients with DM, participate in the development of a local inflammatory reaction.Determine the cells immunophenotype of atherosclerotic plaques in patients with diabetes.We analyzed 24 patients (20 men and 4 women), who underwent aortofemoral bypass, femoral-tibial bypass or carotid endarterectomy. During the operation, a fragment of the arterial wall with an atherosclerotic plaque was obtained for further immunohistochemical studies. Five histologic plaque characteristics (CD68+, -SMA, CD34, leptin and leptin receptor) were compared.No difference in the expression of CD68 (p=0.922), -SMA (p=0.192), CD34 (p=0.858), leptin receptor (p=0.741) and leptin (p=0.610) in atherosclerotic plaques were observed between patients with and without DM. The lack of significant differences between the two groups was possibly due to the small number of observations with DM. In particular, when assessing the expression of selected markers in atherosclerotic plaques, patients with DM showed significantly more leptin receptors than patients without DM (2160.716 and 1205.88 respectively); and also significantly less CD68+ (0.39 and 0.98 respectively) and -SMA+ (6.5 and 13.5 respectively).Based on the expression of CD68, -SMA, CD34, leptin receptor and leptin, no significant differences were observed in atherosclerotic plaque between patients with and without DM. At the same time, despite the limitations of the study (a small number of patients, moderate severity of DM, elderly patients in the DM group), we found a tendency in the increased number of leptin receptors and a decreased number of -SMA+, CD68+ in DM atherosclerotic plaques. Further study needed, taking into account the limitations of this work.Обоснование. Сахарный диабет (СД) является важным предиктором развития атеросклероза, сердечно-сосудистых заболеваний и смертности от сердечно-сосудистых заболеваний. Известно, что у больных СД атеросклероз возникает раньше, сокращая продолжительность их трудовой деятельности и жизни. Лептин, как и маркеры воспаления, могут способствовать прогрессированию атеросклероза при СД, участвовать в развитии местной воспалительной реакции и патогенезе развития атеросклеротической бляшки. Цель. Изучить иммунофенотип клеток, входящих в состав атеросклеротических бляшек у пациентов с СД. Материалы и методы. Проведено наблюдательное одномоментное двухцентровое исследование, в которое включены 24 пациента (20 мужчин и 4 женщины), подвергшиеся аорто-феморальному, бедренно-берцовому шунтированию или каротидной эндартерэктомии. В ходе проведения операции получен фрагмент артериальной стенки с атеросклеротической бляшкой для дальнейшего проведения иммуногистохимического исследования: оценки экспрессии CD68+ макрофагов, -SMA (-гладкомышечный актин), CD34, лептина и рецептора лептина. Результаты. При сравнении результатов оценки экспрессии CD68 (p=0,922), -SMA (p=0,192), CD34 (p=0,858), рецептора лептина (p=0,741) и лептина (p=0,610) в атеросклеротических бляшках статистически значимых различий между группами пациентов с СД и без СД не выявлено. Отсутствие достоверных различий между двумя группами, возможно, обусловлено небольшим количеством наблюдений пациентов с СД. В частности, при оценке экспрессии выбранных маркеров в атеросклеротических бляшках у больных СД отмечено значительно больше рецепторов лептина, чем у лиц без СД (2160,716 и 1205,88 соответственно), а также значительно меньше CD68+ (0,39 и 0,98 соответственно) и -SMA+ (6,5 и 13,5 соответственно). Заключение. На основании оценки экспрессии CD68, -SMA, CD34, рецептора лептина и лептина не выявлено достоверных различий в структуре атеросклеротической бляшки у пациентов с СД и без. В то же время, несмотря на ограничения исследования (небольшое число больных, умеренная тяжесть СД, пожилой возраст пациентов в группе с нарушением углеводного обмена), мы обнаружили тенденцию в увеличении количества рецепторов лептина и уменьшении количества -SMA+, CD68+ у больных СД. Требуется дальнейшее изучение этой проблемы с учетом ограничений данной работы.

Raine syndrome is a rare hereditary disease caused by mutations in the FAM20C gene. Only 18 non-lethal cases have been reported, the majority of them being children and young adults aged up to 30. Due to the rarity of the disease, genotype–phenotype correlations are not available and patient life expectancy is unknown, thus making descriptions of each novel case of particular importance. In this article, we describe a case of an Armenian woman, living in Russia, who was followed-up from age 36 to 39, presenting with pain in the extremities, osteosclerosis with periosteal bone formation, multiple calcifications in solid organs, midface hypoplasia, exophthalmos, amelogenesis imperfecta, shortening of distal phalanges, pectus excavatum, and hypophosphatemia due to renal phosphate wasting. Whole exome sequencing was performed on NextSeq 550 (Illumina, USA) and compound heterozygous variants were identified in the FAM20C gene (reference sequence NM_020223): a frameshift insertion c.1107_1108insTACTG (p.Tyr369fs) and a missense substitution c.1375C > G (p.Arg459Gly). This is the first reported case of a middle-aged patient presenting classical symptoms of Raine syndrome caused by novel compound heterozygous mutations in the conserved C-terminal domain of FAM20C gene.

The reaction of homophthalic anhydride with 1H-indol-3-carbaldimines was used for the preparation of trans- and cis-2-alkyl-3-indolyl-1-oxotetrahydroisoquinolin-4-carboxylic acids 3a–d. The stereochemistry of the reaction was investigated by means of 1H NMR spectroscopy. The carboxylic group of trans-3a–d was transformed stereoselectively via 4-hydroxymethyltetrahydroisoquinolin-1-ones into 4-(phthalimidomethyl)-derivatives trans-6a,b and 4-(imidazolylmethyl)-derivatives trans-8b–d. Compounds trans-6a,b and 8b–d were tested for antiaromatase activity, and the preliminary results showed that the phthalimidomethylisoquinolinone trans-6b at 50 μM concentration decreased the aromatase enzyme activity with 40%.

International journal of molecular sciences 22(22), 12459 (2021). doi:10.3390/ijms222212459 special issue: "Special issue "Cell apoptosis" / special issue editor: Francisco Estevez, guest editor", Published by Molecular Diversity Preservation International, Basel

International journal of molecular sciences 21(22), 8859 (2020). doi:10.3390/ijms21228859 special issue: "Special Issue "Cell Death in Biology and Diseases" / Special Issue Editors: Dr. Peter Richter, Guest Editor; Dr. Marcus Krüger, Co-Guest Editor", Published by Molecular Diversity Preservation International, Basel

Introduction Thyrotropin-secreting pituitary adenoma (TSH-oma) is a rare cause of thyrotoxicosis and represents 0.5-3% of all pituitary adenomas. Given the rarity of the disease and the lack of extensive clinical experience in world practice, the analysis of each case of TSH-secreting pituitary tumors is extremely relevant. Materials and methods: We enrolled consecutive patients with TSH secreting pituitary adenoma. TSH (0,25-3,5 mIU/L), FT4 (9-20 pmol/l) FT3 (2,5-5,5 pmol/l) were measured by Architect i2000SR (Abbott Laboratories, Abbott Park, Illinois, U.S.A). An octreotide test consisted of injecting short-acting somatostatin analogue (SSA) at a dose of 100 μg 3 times a day subcutaneously during 3 days or long-acting SSA 20 mg in 28 days minimum for two months and measuring thyroid profile blood tests before and at the end of the test. MRI was performed on GE Optima MR450w 1.5T. Results: We present 28 case series with TSH-omas followed in our center from 2010 to 2019, the median age - 46 (from 10 to 71 years) with a predominance of a female (21 cases) over a male (7 cases). Clinical manifestations included cardiac arrhythmias (82.1%), neurological changes (60.7%), visual impairment (39.3%), osteoporosis (28.6%), hypopituitarism (7.1%). At first admission, 17 patients had increased TSH, FT3 and FT4; in 7 patients - FT3 and FT4 only, and in 4 - an increase was in one of the hormones; mean value of TSH was 5,04 mIU/L, FT4 - 24,46 pmol/l, FT3 - 8,9 pmol/l. SSBG, CTx, osteocalcin were elevated in 60.9%, 57.9% and 31.6% of cases, respectively. In 88.5% of cases octreotide test led to thyroid hormones normalization. On MRI macroadenomas was registered in 67.9%. In 12 patients, diagnosis was confirmed by immunohistochemical examination. In 12 patients, the diagnosis verification was based on remission after surgical and medical treatment. In the remaining four cases, the diagnosis was made on clinical and laboratory data, however, confirmation was inconceivable due to inefficacy of medical treatment. Remission was achieved in 23 patients: 17 of 21 after neurosurgery (81%), 3 of 7 after primary administration of SSA, and 3 after administration of SSA after surgery (100% remission in cases of combined treatment and 42.9% of monotherapy); 3 out of 5 patients who did not achieve remission were lost for observation. Two patients died: in one case due to the brain herniation and cachexia in active thyrotoxicosis. In second case, the patient developed a mental disorder (catatonia) after the second transphenoidal adenomectomy, which led to death. Conclusion The diagnosis of TSH-oma should be based on all thyroid hormones assessment, since biochemical thyrotoxicosis can manifest itself in various ways. The most effective treatment is transphenoidal adenomectomy. If a neurosurgery is not effective or contraindicative, preoperative preparations SSA can be used.

The ubiquitin-editing protein A20 (TNFAIP3) is a known key player in the regulation of immune responses in many organs. Genome-wide associated studies (GWASs) have linked A20 with a number of inflammatory and autoimmune disorders, including psoriasis. Here, we identified a previously unrecognized role of A20 as a pro-apoptotic factor in TNF-induced cell death in keratinocytes. This function of A20 is mediated via the NF-&kappa, B-dependent alteration of cIAP1/2 expression. The changes in cIAP1/2 protein levels promote NIK stabilization and subsequent activation of noncanonical NF-&kappa, B signaling. Upregulation of TRAF1 expression triggered by the noncanonical NF-&kappa, B signaling further enhances the NIK stabilization in an autocrine manner. Finally, stabilized NIK promotes the formation of the ripoptosome and the execution of cell death. Thus, our data demonstrate that A20 controls the execution of TNF-induced cell death on multiple levels in keratinocytes. This signaling mechanism might have important implications for the development of new therapeutic strategies for the treatment of A20-associated skin diseases.

Introduction: Multiple endocrine neoplasia type 1 syndrome (MEN 1) is caused by mutations in MEN1 gene, encoding menin protein. A combination of pituitary adenomas (PA) and primary hyperparathyroidism (PHPT) in patients without MEN1 mutations is defined as MEN 1 phenocopy. The aim of the study is to find if there are any differences in menin expression in PA of patients with genetically confirmed MEN 1, MEN 1 phenocopies and sporadic acromegaly. Materials and Methods: Formalin-fixed paraffin-embedded PA tissues were obtained from 9 genetically confirmed MEN 1 patients (group 1), 12 patients with MEN 1 phenocopies (a combination of PA and PHPT) (group 2) and 14 patients with sporadic acromegaly (group 3). The integrity of the tissues was tested by immunohistochemistry (IHC) using antibodies against the nuclear protein Pit-1. MEN1 mutations were confirmed or excluded by Sanger sequencing or by NGS (NextSeq550, Illumina, USA). Expression of menin was assessed using IHC (Anti-Menin antibody — ChIP Grade, Abcam, UK). Results: The distribution of PA by the type of secretion in group 1 was: 3 — ACTH-secreting, 2 — PRL-secreting, 2 — GH+PRL, 1 — TSH+PRL, 1 — ACTH+PRL, 1 — silent gonadotroph adenoma. All 12 PA from group 2 were GH-secreting. All 14 PA in group 3 were GH-secreting without mixed secretion. The median age at the moment of transsphenoidal surgery in group 1 was 35 years [27; 47], in group 2 — 59 years [56; 65], in group 3 — 56 years [53; 62]. There were 2 men and 7 women in group 1; 2 men and 10 women in group 2; 4 men and 10 women in group 3. In group 1 patients did not receive somatostation analogues (SSA), 7 patients received cabergoline. In group 2 seven patients received SSA, in group 3 — 4 patients received SSA, 2 patients received cabergoline. The results of menin staining were (negative staining/positive cytoplasmic staining/positive nuclear staining): group 1 — 4/4/0; group 2 — 0/11/1; group 3 — 1/7/6. Phenocopy group showed significantly more cytoplasmic expression of menin than in MEN 1 group (p Conclusion: Menin expression is generally preserved in PA in MEN 1 phenocopies and sporadic acromegaly, though with different pattern of nuclear and cytoplasmic expression, while its expression varies in PA in MEN 1. These findings suggest that pathogenesis of PA in MEN 1 phenocopies and sporadic acromegaly may have similarities. The mechanisms of co-occurrence of PA and PHPT in MEN 1 phenocopies are poorly understood and epigenetic modifications downstream menin interacting pathways could play a role.

The MHC class I presentation is responsible for the presentation of viral proteins to CD8+ T lymphocytes and mainly depends on the classical antigen processing pathway. Recently, a second pathway involving autophagy has been implicated in this process. Here, we show an increase in the capacity of murine dendritic cells (DCs) to present viral antigens on MHC class I after infection with a mutant herpes simplex virus 1 (HSV-1-Δ34.5), lacking infected cell protein 34.5 (ICP34.5), when compared to its parental HSV-1 strain. The ICP34.5 protein counteracts host cell translational arrest and suppresses macroautophagy, and the lack of this protein resulted in a low viral protein abundance, which was processed and presented in an efficient way. Our study demonstrates an important role of autophagy in processing endogenous viral proteins in HSV-1-infected DCs.

In the last decade, significant progress has been made in understanding skin cancer cell death resistance mechanisms, and a number of new treatment strategies have been developed. Systematic approach genomic studies of various cancer types have opened new possibilities for the development of anticancer therapies. However, there are still fundamental gaps in the challenging biomedical puzzle, which will form a complete picture for curing cancer. Thus, herein, we describe some of the current cancer treatment strategies and discuss additional cell signalling pathways that could be potential targets for skin cancer treatment.

Nucleoside reverse transcriptase inhibitors (NRTI), such as zidovudine (AZT), are constituents of HIV-1 therapy and are used for the prevention of mother-to-child transmission. Prolonged thymidine analogue exposure has been associated with mitochondrial toxicities to heart, liver, and skeletal muscle. We hypothesized that the thymidine analogue AZT might interfere with autophagy in myocytes, a lysosomal degradation pathway implicated in the regulation of mitochondrial recycling, cell survival, and the pathogenesis of myodegenerative diseases. The impact of AZT and lamivudine (3TC) on C2C12 myocyte autophagy was studied using various methods based on LC3-green fluorescent protein overexpression or LC3 staining in combination with Western blotting, flow cytometry, and confocal and electron microscopy. Lysosomal and mitochondrial functions were studied using appropriate staining for lysosomal mass, acidity, cathepsin activity, as well as mitochondrial mass and membrane potential in combination with flow cytometry and confocal microscopy. AZT, but not 3TC, exerted a significant dose- and time-dependent inhibitory effect on late stages of autophagosome maturation, which was reversible upon mTOR inhibition. Inhibition of late autophagy at therapeutic drug concentrations led to dysfunctional mitochondrial accumulation with membrane hyperpolarization and increased reactive oxygen species (ROS) generation and, ultimately, compromised cell viability. These AZT effects could be readily replicated by pharmacological and genetic inhibition of myocyte autophagy and, most importantly, could be rescued by pharmacological stimulation of autophagolysosomal biogenesis. Our data suggest that the thymidine analogue AZT inhibits autophagy in myocytes, which in turn leads to the accumulation of dysfunctional mitochondria with increased ROS generation and compromised cell viability. This novel mechanism could contribute to our understanding of the long-term side effects of antiviral agents.

Melanoma cells are highly resistant to conventional genotoxic agents, and BRAFV600/MEK-targeted therapies as well as immunotherapies frequently remain inefficient. Alternative means to treat melanoma, in particular through the induction of programmed cell death modalities such as apoptosis or necroptosis, therefore still need to be explored. Here, we report that melanoma cell lines expressing notable amounts of RIPK1, RIPK3 and MLKL, the key players of necroptosis signal transduction, fail to execute necroptotic cell death. Interestingly, the activity of transforming growth factor β-activated kinase 1 (TAK1) appears to prevent RIPK1 from contributing to cell death induction, since TAK1 inhibition by (5Z)-7-Oxozeaenol, deletion of MAP3K7 or the expression of inactive TAK1 were sufficient to sensitize melanoma cells to RIPK1-dependent cell death in response to TNFα or TRAIL based combination treatments. However, cell death was executed exclusively by apoptosis, even when RIPK3 expression was high. In addition, TAK1 inhibitor (5Z)-7-Oxozeaenol suppressed intrinsic or treatment-induced pro-survival signaling as well as the secretion of cytokines and soluble factors associated with melanoma disease progression. Correspondingly, elevated expression of TAK1 correlates with reduced disease free survival in patients diagnosed with primary melanoma. Overall, our results therefore demonstrate that TAK1 suppresses the susceptibility to RIPK1-dependent cell death and that high expression of TAK1 indicates an increased risk for disease progression in melanoma.

Autoimmune polyendocrine syndromes (APS) are a heterogeneous group of diseases characterized by the presence of autoimmune dysfunction of 2 or more endocrine glands and other non-endocrine organs. The components of the syndrome can manifest throughout life: in childhood—APS type 1 (the juvenile type) and in adulthood—APS type 2, 3, and 4 (the adult types). Adult types of APS are more common in clinical practice. It is a polygenic disease associated with abnormalities in genes encoding key regulatory proteins of the major histocompatibility complex (MHC). The search of for candidate genes responsible for mutations in adult APS is continuing. Genetic predisposition is insufficient for the manifestation of the APS of adults, since the penetrance of the disease, even among monozygotic twins, does not approach 100% (30–70%). The article presents the case of isolated Addison’s disease and APS type 2 in monozygotic twins with a revealed compound heterozygosity in the candidate gene VTCN1.

Receptor-interacting protein kinase 1 (RIPK1) represents an essential signaling node in cell death and inflammation. Ablation of Ripk1 in liver parenchymal cells (LPC) did not cause a spontaneous phenotype, but led to tumor necrosis factor (TNF)-dependent hepatocyte apoptosis and liver injury without affecting inducible nuclear factor κB (NF-κB) activation. Loss of Ripk1 induced the TNF-dependent proteasomal degradation of the E3-ligase, TNF receptor-associated factor 2 (TRAF2), in a kinase-independent manner, thereby activating caspase-8. Moreover, loss of both Ripk1 and Traf2 in LPC not only resulted in caspase-8 hyperactivation but also impaired NF-κB activation, promoting the spontaneous development of hepatocellular carcinoma. In line, low RIPK1 and TRAF2 expression in human HCCs was associated with an unfavorable prognosis, suggesting that RIPK1 collaborates with TRAF2 to inhibit murine and human hepatocarcinogenesis.

The MHC class I presentation is responsible for the presentation of viral proteins to CD8

Histone deacetylase (HDAC) inhibitors (HDACis) are well-characterized anti-cancer agents with promising results in clinical trials. However, mechanistically little is known regarding their selectivity in killing malignant cells while sparing normal cells. Gene expression-based chemical genomics identified HDACis as being particularly potent against Down syndrome-associated myeloid leukemia (DS-AMKL) blasts. Investigating the antileukemic function of HDACis revealed their transcriptional and post-translational regulation of key autophagic proteins, including ATG7. This leads to suppression of autophagy, a lysosomal degradation process that can protect cells against damaged or unnecessary organelles and protein aggregates. DS-AMKL cells exhibit low baseline autophagy due to mammalian target of rapamycin (mTOR) activation. Consequently, HDAC inhibition repressed autophagy below a critical threshold, which resulted in accumulation of mitochondria, production of reactive oxygen species, DNA damage and apoptosis. Those HDACi-mediated effects could be reverted upon autophagy activation or aggravated upon further pharmacological or genetic inhibition. Our findings were further extended to other major acute myeloid leukemia subgroups with low basal level autophagy. The constitutive suppression of autophagy due to mTOR activation represents an inherent difference between cancer and normal cells. Thus, via autophagy suppression, HDACis deprive cells of an essential pro-survival mechanism, which translates into an attractive strategy to specifically target cancer cells.

Lipoatrophy in HIV patients can result from prolonged exposure to thymidine analogues. Mitochondrial toxicity leading to dysregulated adipogenesis and increased cell death has been proposed as a leading factor in the etiology of peripheral fat loss. We hypothesized that thymidine analogues interfere with autophagy, a lysosomal degradation pathway, which is important for mitochondrial quality control, cellular survival, and adipogenesis. We assessed the effects of zidovudine (AZT), stavudine (d4T), and lamivudine (3TC) on autophagy in eukaryotic cells and adipocytes (3T3-F442A) by fluorescence microscopy and flow cytometry. The effects were compared to interventions with established genetic and pharmacological inhibitors of autophagy and correlated to assessments of cell viability, proliferation, and differentiation. AZT and d4T, but not 3TC, inhibited both constitutive and induced autophagic activity in adipocytes. This inhibition was associated with accumulation of dysfunctional mitochondria, increased reactive oxygen species (ROS) production, increased apoptosis, decreased proliferation, and impaired adipogenic conversion. Autophagy inhibition was dose and time dependent and detectable at therapeutic drug concentrations. Similar phenotypic changes were obtained when genetic or pharmacological inhibition of autophagy was employed. Our data suggest that thymidine analogues disturb adipocyte function through inhibition of autophagy. This novel mechanism potentially contributes to peripheral fat loss in HIV-infected patients.

Prosody, particularly accent, aids comprehension by drawing attention to important elements such as the information that answers a question. A study using ERP registration investigated how the brain deals with the interpretation of prosodic prominence. Sentences were embedded in short dialogues and contained accented elements that were congruous or incongruous with respect to a preceding question. In contrast to previous studies, no explicit prosodic judgment task was added. Robust effects of accentuation were evident in the form of an “accent positivity” (200–500 msec) for accented elements irrespective of their congruity. Our results show that incongruously accented elements, that is, superfluous accents, activate a specific set of neural systems that is inactive in case of incongruously unaccented elements, that is, missing accents. Superfluous accents triggered an early positivity around 100 msec poststimulus, followed by a right-lateralized negative effect (N400). This response suggests that redundant information is identified immediately and leads to the activation of a neural system that is associated with semantic processing (N400). No such effects were found when contextually expected accents were missing. In a later time window, both missing and superfluous accents triggered a late positivity on midline electrodes, presumably related to making sense of both kinds of mismatching stimuli. These results challenge previous findings of greater processing for missing accents and suggest that the natural processing of prosody involves a set of distinct, temporally organized neural systems.

Objectives: Prolonged nucleoside reverse transcriptase inhibitors (NRTI) exposure can lead to microvesicular steatosis. We hypothesized that thymidine analogues might interfere with autophagy in hepatocytes, a lysosomal degradation pathway implicated in cell survival and regulation of hepatocyte lipid metabolism. Design: Using HepG2 and HUH7 cell lines and primary human hepatocytes, we performed a comprehensive analysis of NRTI-mediated effects on autophagy. Methods: The impact of zidovudine (ZDV), stavudine (d4T) and lamivudine (3TC) on constitutive and induced autophagy was analyzed by fluorescent and electron microscopy, western blotting and flow cytometry. Effects on hepatocyte autophagy were correlated to cellular viability, mitochondrial dysfunction and intracellular lipid accumulation. Results: ZDV and d4T, but not 3TC, significantly inhibited both constitutive as well as stimulated autophagic activity in a dose-dependent and time-dependent manner. Inhibition of autophagy at therapeutic drug concentrations led to accumulation of dysfunctional mitochondria, increased ROS production, increased apoptosis, decreased proliferation and increased intracellular lipid accumulation. These NRTI effects could be readily resembled by pharmacological and genetic inhibition of hepatocyte autophagy. Conclusion: Our data suggest that thymidine analogues inhibit autophagy in hepatocytes, which in turn leads to increased ROS production, lipid accumulation and hepatic dysfunction. This novel mechanism could contribute to nonalcoholic fatty liver disease in HIV-infected patients.

At an unbelievable pace, recent evidence has emerged that demonstrates the importance of a programmed form of necrosis (necroptosis) in physiology, pathophysiology and embryonic development. It is clear that the understanding of the intracellular control of necroptosis as compared to caspase-dependent apoptosis is of paramount importance. Tumorigenesis, immune surveillance of cancer and pathogen-induced disease, to name only a few, appear to be affected by the mode of cell death in vivo. Here, we discuss the Ripoptosome, a newly defined 2 MDa intracellular signalling complex that can be formed upon genotoxic stress or loss of inhibitor-of apoptosis proteins (IAPs). The Ripoptosome is a signaling platform that can switch modes between apoptotic and necroptotic cell death. In this report, we extend our recent studies and further the notion that the stoichiometric balance between RIP1 and cIAPs is critical for Ripoptosome formation. Furthermore, we demonstrate the critical relevance of the balance of expression levels of short (cFLIPS) or viral (vFLIP) forms of FLIP and RIP3 kinase for the spontaneous execution of necroptosis whenever cIAPs are absent in the cells. Our study thus supports and extends the intriguing role of the Ripoptosome for the regulation of apoptosis and necroptosis.

Summary The intracellular regulation of cell death pathways by cIAPs has been enigmatic. Here we show that loss of cIAPs promotes the spontaneous formation of an intracellular platform that activates either apoptosis or necroptosis. This 2 MDa intracellular complex that we designate "Ripoptosome" is necessary but not sufficient for cell death. It contains RIP1, FADD, caspase-8, caspase-10, and caspase inhibitor cFLIP isoforms. cFLIP L prevents Ripoptosome formation, whereas, intriguingly, cFLIP S promotes Ripoptosome assembly. When cIAPs are absent, caspase activity is the "rheostat" that is controlled by cFLIP isoforms in the Ripoptosome and decides if cell death occurs by RIP3-dependent necroptosis or caspase-dependent apoptosis. RIP1 is the core component of the complex. As exemplified by our studies for TLR3 activation, our data argue that the Ripoptosome critically influences the outcome of membrane-bound receptor triggering. The differential quality of cell death mediated by the Ripoptosome may cause important pathophysiological consequences during inflammatory responses.

Death receptors (DRs) induce apoptosis but also stimulate proinflammatory "non-apoptotic" signaling (e.g. NF-κB and mitogen-activated protein kinase (MAPK) activation) and inhibit distinct steps of DR-activated maturation of procaspase-8. To examine whether isoforms of cellular FLIP (cFLIP) or its cleavage products differentially regulate DR signaling, we established HaCaT cells expressing cFLIP(S), cFLIP(L), or mutants of cFLIP(L) (cFLIP(D376N) and cFLIP(p43)). cFLIP variants blocked TRAIL- and CD95L-induced apoptosis, but the cleavage pattern of caspase-8 in the death inducing signaling complex was different: cFLIP(L) induced processing of caspase-8 to the p43/41 fragments irrespective of cFLIP cleavage. cFLIP(S) or cFLIP(p43) blocked procaspase-8 cleavage. Analyzing non-apoptotic signaling pathways, we found that TRAIL and CD95L activate JNK and p38 within 15 min. cFLIP variants and different caspase inhibitors blocked late death ligand-induced JNK or p38 MAPK activation suggesting that these responses are secondary to cell death. cFLIP isoforms/mutants also blocked death ligand-mediated gene induction of CXCL-8 (IL-8). Knockdown of caspase-8 fully suppressed apoptotic and non-apoptotic signaling. Knockdown of cFLIP isoforms in primary human keratinocytes enhanced CD95L- and TRAIL-induced NF-κB activation, and JNK and p38 activation, underscoring the regulatory role of cFLIP for these DR-mediated signals. Whereas the presence of caspase-8 is critical for apoptotic and non-apoptotic signaling, cFLIP isoforms are potent inhibitors of TRAIL- and CD95L-induced apoptosis, NF-κB activation, and the late JNK and p38 MAPK activation. cFLIP-mediated inhibition of CD95 and TRAIL DR could be of crucial importance during keratinocyte skin carcinogenesis and for the activation of innate and/or adaptive immune responses triggered by DR activation in the skin.

Single muscle fibers with multiple axonal endplates (multiply innervated fibers) are normally present in adult extraocular muscles (EOMs), while most other mammalian skeletal muscles contain fibers with a single myoneural junction. Recent findings by others led us to investigate for the presence of polyneuronal innervation (innervation of a single muscle fiber by >1 motoneuron) in the inferior oblique (IO) muscle of pentobarbital anesthetized cats. The IO muscle nerve branches, as they coursed through the orbit, were further divided for independent or simultaneous electrical stimulation with bipolar electrodes. Four of five established tests for polyneuronal innervation gave positive results. The sum of the twitch (1) and tetanic (2) tensions in response to individual nerve branch stimulation was greater than that for simultaneous (whole) nerve stimulation. The summed electromyographic (EMG) responses (3) gave a similar positive result. The result for crossed tetanic potentiation (4) was negative for polyneuronal innervation while the crossed fatigue (5) test was positive. These results are consistent with recent studies. That the EOMs exhibit polyneuronal innervation further explains the eye-movement system's functional integrity during some neuromuscular disorders as well as its ability to operate with precision after the loss of numerous motoneurons.

Toxic epidermal necrolysis (TEN) is a rare but potentially fatal drug hypersensitivity reaction. Although a number of pathophysiological hints have been identified over the past decade, details of the effector mechanisms within the skin remain obscure. A novel study by Kim et al. now sheds light on its pathophysiology. The investigators demonstrate convincingly that receptor-interacting kinase 3 (RIPK3) levels are upregulated substantially in the lesional skin of patients with TEN and that this is followed by the generation of reactive oxygen species, activation of mixed lineage kinase-like protein, and subsequent necroptotic cell death of keratinocytes. These data suggest that therapies that interfere with RIPK3 activation and necroptosis induction could benefit patients with TEN.

Current research on spoken language does not provide a consistent picture as to whether prosody, the melody and rhythm of speech, conveys a specific meaning. Perception studies show that English listeners assign meaning to prosodic patterns, and, for instance, associate some accents with contrast, whereas Dutch listeners behave more controversially. In two ERP studies we tested how Dutch listeners process words carrying two types of accents, which either provided new information (new information accents) or corrected information (corrective accents), both in single sentences (experiment 1) and after corrective and new information questions (experiment 2). In both experiments corrective accents elicited a sustained positivity as compared to new information accents, which started earlier in context than in single sentences. The positivity was not modulated by the nature of the preceding question, suggesting that the underlying neural mechanism likely reflects the construction of an interpretation to the accented word, either by identifying an alternative in context or by inferring it when no context is present. Our experimental results provide strong evidence for inferential processes related to prosodic contours in Dutch.