Skeletal muscle fibre type-dependent effects of atorvastatin on the PI3K/Akt/mTOR signalling pathway and atrophy-related genes in rats.

BACKGROUND: One of the probable causes of statin myotoxicity is an imbalance between protein synthesis and degradation. These processes are regulated by the PI3K/Akt/mTOR pathway and the ubiquitin‒proteasome system (UPS). The aim of this study was to assess whether the effects of atorvastatin on PI3K/Akt/mTOR pathway downstream proteins, the FoxO3a transcription factor and the UPS genes, i.e., MuRF-1 and MAFbx, depend on muscle fibre type. METHODS AND RESULTS: Atorvastatin (50 mg/kg) was administered to Wistar rats. The levels of selected PI3K/Akt/mTOR pathway proteins were assayed via Western blotting, whereas MuRF-1, MAFbx and FoxO3a mRNA levels were measured using reverse transcription quantitative polymerase chain reaction (RT‒qPCR). Gomöri trichrome staining was performed to assess skeletal muscle pathology. A decrease in the P-Akt/Akt ratio was observed in the gastrocnemius muscle (MG), whereas an increase in the P-Akt/Akt ratio was observed in the soleus muscle (SOL). FoxO3a gene expression increased in the SOL and extensor digitorum longus (EDL) muscles. MuRF-1 gene expression increased in the MG, and MAFbx expression increased in the EDL. No histopathological changes were observed in any of the tested muscles. CONCLUSIONS: In the absence of overt muscle damage, atorvastatin decreased the P-Akt/Akt ratio in the MG, indicating an increase in inactive Akt. Consistent with the decrease in Akt activation, rpS6 phosphorylation decreased. In SOL, atorvastatin increased the P-Akt/Akt ratio, indicating Akt activation. P-FoxO3a and the P-FoxO3a/FoxO3a ratio increased, suggesting that FoxO3a inactivation occurred. Moreover, in the SOL, atorvastatin did not affect the expression of atrophy-related genes. These findings indicate that atorvastatin has no adverse effect on the Akt pathway in the SOL. Our results showed that the effects of atorvastatin on the Akt signalling pathway and atrophy-related gene expression depend on muscle type.

Variabilities in global DNA methylation and ß-sheet richness establish spectroscopic landscapes among subtypes of pancreatic cancer.

PURPOSE: Knowledge about pancreatic cancer (PC) biology has been growing rapidly in recent decades. Nevertheless, the survival of PC patients has not greatly improved. The development of a novel methodology suitable for deep investigation of the nature of PC tumors is of great importance. Molecular imaging techniques, such as Fourier transform infrared (FTIR) spectroscopy and Raman hyperspectral mapping (RHM) combined with advanced multivariate data analysis, were useful in studying the biochemical composition of PC tissue. METHODS: Here, we evaluated the potential of molecular imaging in differentiating three groups of PC tumors, which originate from different precursor lesions. Specifically, we comprehensively investigated adenocarcinomas (ACs): conventional ductal AC, intraductal papillary mucinous carcinoma, and ampulla of Vater AC. FTIR microspectroscopy and RHM maps of 24 PC tissue slides were obtained, and comprehensive advanced statistical analyses, such as hierarchical clustering and nonnegative matrix factorization, were performed on a total of 211,355 Raman spectra. Additionally, we employed deep learning technology for the same task of PC subtyping to enable automation. The so-called convolutional neural network (CNN) was trained to recognize spectra specific to each PC group and then employed to generate CNN-prediction-based tissue maps. To identify the DNA methylation spectral markers, we used differently methylated, isolated DNA and compared the observed spectral differences with the results obtained from cellular nuclei regions of PC tissues. RESULTS: The results showed significant differences among cancer tissues of the studied PC groups. The main findings are the varying content of ß-sheet-rich proteins within the PC cells and alterations in the relative DNA methylation level. Our CNN model efficiently differentiated PC groups with 94% accuracy. The usage of CNN in the classification task did not require Raman spectral data preprocessing and eliminated the need for extensive knowledge of statistical methodologies. CONCLUSIONS: Molecular spectroscopy combined with CNN technology is a powerful tool for PC detection and subtyping. The molecular fingerprint of DNA methylation and ß-sheet cytoplasmic proteins established by our results is different for the main PC groups and allowed the subtyping of pancreatic tumors, which can improve patient management and increase their survival. Our observations are of key importance in understanding the variability of PC and allow translation of the methodology into clinical practice by utilizing liquid biopsy testing.

Combined analytical approach empowers precise spectroscopic interpretation of subcellular components of pancreatic cancer cells.

The lack of specific and sensitive early diagnostic options for pancreatic cancer (PC) results in patients being largely diagnosed with late-stage disease, thus inoperable and burdened with high mortality. Molecular spectroscopic methodologies, such as Raman or infrared spectroscopies, show promise in becoming a leader in screening for early-stage cancer diseases, including PC. However, should such technology be introduced, the identification of differentiating spectral features between various cancer types is required. This would not be possible without the precise extraction of spectra without the contamination by necrosis, inflammation, desmoplasia, or extracellular fluids such as mucous that surround tumor cells. Moreover, an efficient methodology for their interpretation has not been well defined. In this study, we compared different methods of spectral analysis to find the best for investigating the biomolecular composition of PC cells cytoplasm and nuclei separately. Sixteen PC tissue samples of main PC subtypes (ductal adenocarcinoma, intraductal papillary mucinous carcinoma, and ampulla of Vater carcinoma) were collected with Raman hyperspectral mapping, resulting in 191,355 Raman spectra and analyzed with comparative methodologies, specifically, hierarchical cluster analysis, non-negative matrix factorization, T-distributed stochastic neighbor embedding, principal components analysis (PCA), and convolutional neural networks (CNN). As a result, we propose an innovative approach to spectra classification by CNN, combined with PCA for molecular characterization. The CNN-based spectra classification achieved over 98% successful validation rate. Subsequent analyses of spectral features revealed differences among PC subtypes and between the cytoplasm and nuclei of their cells. Our study establishes an optimal methodology for cancer tissue spectral data classification and interpretation that allows precise and cognitive studies of cancer cells and their subcellular components, without mixing the results with cancer-surrounding tissue. As a proof of concept, we describe findings that add to the spectroscopic understanding of PC.

Recommendations of the Polish Association of Neuropathologists on performing post-mortem examination of the brain and spinal cord.

Neuropathological central nervous system (CNS) post-mortem examination is a highly specialistic element of the autopsy procedure with methodological specificity. Herein we propose updated recommendations for CNS autopsy for pathologists and neuropathologists. The protocol includes the compendium of neuroanatomy with current nomenclature, consecutive steps of gross examination, as well as appropriate sampling algorithms in different clinical and pathological settings. The significance of pathoclinical cooperation in differential diagnosis is exposed. We believe it is essential to create and promote the guidelines to improve the quality of CNS post-mortem examination at the national level.

Raman Spectroscopy as a Potential Adjunct of Thyroid Nodule Evaluation: A Systematic Review.

The incidence of thyroid nodules (TNs) is estimated at 36.5% and 23% in females and males, respectively. A single thyroid nodule is usually detected during ultrasound assessment in patients with symptoms of thyroid dysfunction or neck mass. TNs are classified as benign tumours (non-malignant hyperplasia), benign neoplasms (e.g., adenoma, a non-invasive follicular tumour with papillary nuclear features) or malignant carcinomas (follicular cell-derived or C-cell derived). The differential diagnosis is based on fine-needle aspiration biopsies and cytological assessment (which is burdened with the bias of subjectivity). Raman spectroscopy (RS) is a laser-based, semiquantitative technique which shows for oscillations of many chemical groups in one label-free measurement. RS, through the assessment of chemical content, gives insight into tissue state which, in turn, allows for the differentiation of disease on the basis of spectral characteristics. The purpose of this study was to report if RS could be useful in the differential diagnosis of TN. The Web of Science, PubMed, and Scopus were searched from the beginning of the databases up to the end of June 2023. Two investigators independently screened key data using the terms "Raman spectroscopy" and "thyroid". From the 4046 records found initially, we identified 19 studies addressing the differential diagnosis of TNs applying the RS technique. The lasers used included 532, 633, 785, 830, and 1064 nm lines. The thyroid RS investigations were performed at the cellular and/or tissue level, as well as in serum samples. The accuracy of papillary thyroid carcinoma detection is approx. 90%. Furthermore, medullary, and follicular thyroid carcinoma can be detected with up to 100% accuracy. These results might be biased with low numbers of cases in some research and overfitting of models as well as the reference method. The main biochemical changes one can observe in malignancies are as follows: increase of protein, amino acids (like phenylalanine, tyrosine, and tryptophan), and nucleic acid content in comparison with non-malignant TNs. Herein, we present a review of the literature on the application of RS in the differential diagnosis of TNs. This technique seems to have powerful application potential in thyroid tumour diagnosis.

Elemental Composition of Skeletal Muscle Fibres Studied with Synchrotron Radiation X-ray Fluorescence (SR-XRF).

Diseases of the muscle tissue, particularly those disorders which result from the pathology of individual muscle cells, are often called myopathies. The diversity of the content of individual cells is of interest with regard to their role in both biochemical mechanisms and the structure of muscle tissue itself. These studies focus on the preliminary analysis of the differences that may occur between diseased tissues and tissues that have been recognised as a reference group. To do so, 13 samples of biopsied human muscle tissues were studied: 3 diagnosed as dystrophies, 6 as (non-dystrophic) myopathy and 4 regarded as references. From these sets of muscle biopsies, 135 completely measured muscle fibres were separated altogether, which were subjected to investigations using synchrotron radiation X-ray fluorescence (SR-XRF). Muscle fibres were analysed in terms of the composition of elements such as Br, Ca, Cl, Cr, Cu, Fe, K, Mn, P, S and Zn. The performed statistical tests indicate that all three groups (dystrophies-D; myopathies-M; references-R) show statistically significant differences in their elemental compositions, and the greatest impact, according to the multivariate discriminate analysis (MDA), comes from elements such as Ca, Cu, K, Cl and S.

Central nervous system autopsy - a neuropathological procedure based on multidisciplinary pathoclinical cooperation.

INTRODUCTION: Neuropathological brain and spinal cord post mortem examination is a distinct procedure that still plays an important role in modern medicine. In front of increasing amounts of clinical and genetic data, together with important developments in the field of neuroimaging, the Polish Association of Neuropathologists have updated their recommendations regarding central nervous system (CNS) examination. These guidelines are aimed at neuropathologists, pathologists and clinicians. AIM OF THE STUDY: Presentation of the outlined recommendations as their goal is to improve the quality, informativity, and cost effectiveness of CNS post mortem examinations. A comprehensive study of the literature was conducted to provide a clinical background of neuropathological autopsy. There are numerous open questions in neuroscience, and new strategies are required to foster research in CNS diseases. These include the challenge of organizing brain banks tasked with managing and protecting detailed multidisciplinary information about their resources. Complex neuropathological analyses of post mortem series are also important to assess the effectiveness of diagnostics and therapy, identify environmental impact on the development of neurological disorders, and improve public health policy. The recommendations outline the need for collaboration between multiple specialists to establish the proper diagnosis and to broaden knowledge of neurological disorders.

Complex grade III astrocytoma with granular cells and PXA features in a patient with tuberous sclerosis complex (Bourneville-Pringle syndrome) - case report and review of literature.

Tuberous sclerosis complex (Bourneville-Pringle syndrome) is a rare genetic condition included in the group of diseases called phakomatoses. Most of the patients are diagnosed with abnormalities within the central nervous system and tend to develop tumors more frequently, especially gliomas. We present a case of 50-year-old patient suffering from tuberous sclerosis complex, who had been diagnosed with pleomorphic xanthoastrocytoma (PXA). The patient underwent surgery and adjuvant radiotherapy and has remained free from local recurrence for 5 years.

Extensive squamous metaplasia (morulosis) of the endometrium as a clinical and pathological problem: a case report and literature study.

The article presents a case of a 28-year-old woman with so-called morulosis - a form of squamous metaplasia of the endometrium, which may mimic malignancy. The term 'morulosis' indicates extensive squamous mulberry-like metaplasia, which in a large part or nearly entirely affects endometrium, whereas in turn, benign squamous metaplasia or single morules, refers to a limited, usually small regional pathology of endometrium. Because the endometrial glands and stroma gradually undergo the process of squamous metaplasia, in a scanty biopsy material the picture may lead to overdiagnosis. In the epithelioid regions small inactive glands with an immunofenotype different from the remaining endometrium might be observed. So far 21 cases have been reported in English literature. The patients (age 19-45) had presented with abnormal bleeding, infertility or after hormonal therapy. The mechanism of the extensive squamous metaplasia of endometrium is still not clear. The prevailing view holds that morulosis appears to be a result of hormonal imbalance. To shed light on possible pathogenic background of morulosis, we present a case of particularly severe extensive squamous metaplasia of the endometrium (morulosis).

Laparoscopic Intervention in Acute Crohn's Disease Involving an Ovary.

Crohn's disease (CD) is a chronic inflammatory disorder that may involve any part of the gastrointestinal tract. Acute manifestations in female internal reproductive organs are rare and have been described in only a few cases. A 27-year-old nulligravida woman diagnosed with CD presented with pelvic pain, fever, and a palpable mass (confirmed by ultrasound) in the right lower quadrant of the abdomen. She underwent diagnostic laparoscopy because of worsening symptoms suggestive of a tubo-ovarian abscess. The right adnexa were excised after adhesiolysis. Pathologic examination revealed an ovarian granuloma consistent with CD. This case shows that a laparoscopic approach is possible for active CD, with all the benefits of a minimally invasive approach. Although the involved ovary was removed, similar to previous reports using laparotomy, conservative therapy should be considered if preoperative diagnosis can be made. Improvements in preoperative diagnosis and development of management guidelines is critical for ovarian preservation and conservative treatment options.

Proteomic Analysis of Mitochondria-Enriched Fraction Isolated from the Frontal Cortex and Hippocampus of Apolipoprotein E Knockout Mice Treated with Alda-1, an Activator of Mitochondrial Aldehyde Dehydrogenase (ALDH2).

The role of different genotypes of apolipoprotein E (apoE) in the etiology of Alzheimer's disease is widely recognized. It has been shown that altered functioning of apoE may promote 4-hydroxynonenal modification of mitochondrial proteins, which may result in mitochondrial dysfunction, aggravation of oxidative stress, and neurodegeneration. Mitochondrial aldehyde dehydrogenase (ALDH2) is an enzyme considered to perform protective function in mitochondria by the detoxification of the end products of lipid peroxidation, such as 4-hydroxynonenal and other reactive aldehydes. The goal of our study was to apply a differential proteomics approach in concert with molecular and morphological techniques to elucidate the changes in the frontal cortex and hippocampus of apolipoprotein E knockout (apoE-/-) mice upon treatment with Alda-1-a small molecular weight activator of ALDH2. Despite the lack of significant morphological changes in the brain of apoE-/- mice as compared to age-matched wild type animals, the proteomic and molecular approach revealed many changes in the expression of genes and proteins, indicating the impairment of energy metabolism, neuroplasticity, and neurogenesis in brains of apoE-/- mice. Importantly, prolonged treatment of apoE-/- mice with Alda-1 led to the beneficial changes in the expression of genes and proteins related to neuroplasticity and mitochondrial function. The pattern of alterations implies mitoprotective action of Alda-1, however, the accurate functional consequences of the revealed changes require further research.

The quantitative evaluation of the immunohistochemical expression of the pituitary adenomas.

BACKGROUND: The aim of this study was to evaluate morphometrically the pituitary adenomas immunoexpression. METHODS: The cases of 72 patients were analyzed, who underwent transsphenoidal surgery for pituitary adenomas. Subsequently, the immunohistochemical pituitary hormone panel was applied including alpha- subunit of the glycoprotein hormones. Immunohistochemical sections were analyzed quantitatively with the help of morphometric grid. The percentage rate of the immunoexpression was calculated separately for every single hormone. RESULTS: As a result, 22 monohormonal adenomas (30.56%), 21 plurihormonal adenomas (29.17%), 21 immunonegative adenomas (29.17%) and 8 unreliable cases (11.11%) were recognized. The immunopositivity for particular hormones was found as follows: PRL and GH (25% each), α-SU (22.22%), ACTH (13.89%), LH and FSH (12.5% each), and TSH (5.56%). An average percentage of immunoexpression in each positive staining groups occurred as follows: for PRL - 59.98%, for GH - 53.97%, for ACTH - 39.21%, for TSH - 25.05%, for LH - 37.3%, for FSH - 54.66%, for α-SU - 45.71. CONCLUSION: The morphometrical method utilizing the immunoexpression index introduced in this study provided a very precise recognition of pituitary adenomas pathology. This method may limit the subjectivity of a single researcher and enable better comparison of the studies. The plurihormonality is a common phenomenon, and immunohistochemical staining for all adenohypophyseal hormones is obligatory in order to classify pituitary adenomas correctly. The awareness of an operating neurosurgeon of the importance of meticulous collecting histopathological material, especially in microadenoma cases, has essential impact on further neuropathological evaluation and possibility of immunohistochemical staining.

Prothymosin-alpha and Ki-67 expression in pituitary adenomas.

INTRODUCTION: Prothymosin alpha (PTMA), a nuclear oncoprotein involved in cell cycle regulation, is used as a prognostic marker in many cancers. The histopathology of pituitary carcinomas and locally invasive adenomas is indistinguishable from that of benign tumors. A new marker is needed to differentiate these lesions. We evaluated PTMA in pituitary adenomas to determine its usefulness as a prognostic factor of tumor proliferation. MATERIAL/METHODS: We conducted a retrospective analysis of a group of 27 patients, including 15 females (56%) and 12 males (44%) with a mean age of 58.6±12 years, who underwent pituitary tumor surgery between 2003 and 2012. The Ki-67 and PTMA-nuclear (PTMA-n) and PTMA-cytoplasmic (PTMA-c) indices were determined by immunohistochemical staining. We studied histopathological features, clinical symptoms, and magnetic resonance imaging or computed tomography performed before surgery and one year following surgery to evaluate tumor size and progression. RESULTS: The expression of Ki-67 was revealed in 77.8% of adenomas, PTMA-n in 81.5% and PTMA-c in 92.6%. The mean value of the Ki-67 index was 1.8%, PTMA-n was 1.84%, and PTMA-c was 35.6%. There was a significant positive correlation between Ki-67 and PTMA-n (p=0.009). We did not find any correlation between Ki-67, PTMA-c, and tumor progression. PTMA-n was found to be correlated with tumor size (p=0.045) and was higher in the case of gonadotropinomas (p=0.026). CONCLUSIONS: The positive nuclear expression of Ki-67 and PTMA was observed in the majority of pituitary adenomas. Neither the expression of Ki-67 nor that of PTMA-c was related to tumor recurrence or local invasion.

PTTG and Ki-67 expression in pituitary adenomas.

INTRODUCTION: The unpredictable biology of pituitary adenomas makes it a therapeutic challenge. Moreover ,histopathology of pituitary carcinomas and locally invasive adenomas are indistinguishable from benign tumors and a new marker which would enable to differentiate those lesions is vital. The aim of the study was to evaluate Ki-67 and PTTG (pituitary tumour--transforming gene) expression in pituitary adenomas and their applicationas markers of tumour aggressiveness. MATERIAL AND METHODS: A retrospective analysis of 55 patients: 32 females(58%) and 23 males (42%), mean age 50 ± 16 years who underwent pituitary tumor surgery between 2003-2012. Ki-67 and PTTG indices were determined by immunohistochemical staining. Magnetic resonance imaging or computed tomography was performed beforehand and one year after surgery to figure a potential tumour progression, tumour size and correlation to adjacent tissues. RESULTS: The expression of Ki-67and PTTG was revealed in cell nucleiin 88% and 85% of adenomas, respectively. The median Ki-67 and PTTG indices were 1.4 and 1.0, respectively(p = 0.006). In the group with macroadenoma as compared with the group with microadenoma, median Ki-67 index was higher (1.4% vs. 1.03%; p = 0.02). We did not find correlation between both Ki-67 and PTTG indices and tumour progression. Tumours with positive immunostaining towards FSH revealed lower Ki-67 and PTTG indices than the rest with a negative one (0.6% vs.1.84%, p = 0.0004 and 0.67% vs 1.23%,p = 0.047; respectively). However, PTTG index was higher in the group with acromegaly as compared to the group with clinically non-functioning pituitary adenoma (NFPA) (1.28% vs.0.35%; p = 0.02). CONCLUSIONS: Positive nuclear expression of Ki-67 and PTTG was observed in the majority of pituitary adenomas. Only higher Ki-67 expression was related to the tumour invasiveness found on MRI/CT. Tumour progressionwas not related to both Ki-67 and PTTG expression.

CNS-PNETs with C19MC amplification and/or LIN28 expression comprise a distinct histogenetic diagnostic and therapeutic entity.

Amplification of the C19MC oncogenic miRNA cluster and high LIN28 expression has been linked to a distinctly aggressive group of cerebral CNS-PNETs (group 1 CNS-PNETs) arising in young children. In this study, we sought to evaluate the diagnostic specificity of C19MC and LIN28, and the clinical and biological spectra of C19MC amplified and/or LIN28+ CNS-PNETs. We interrogated 450 pediatric brain tumors using FISH and IHC analyses and demonstrate that C19MC alteration is restricted to a sub-group of CNS-PNETs with high LIN28 expression; however, LIN28 immunopositivity was not exclusive to CNS-PNETs but was also detected in a proportion of other malignant pediatric brain tumors including rhabdoid brain tumors and malignant gliomas. C19MC amplified/LIN28+ group 1 CNS-PNETs arose predominantly in children <4 years old; a majority arose in the cerebrum but 24 % (13/54) of tumors had extra-cerebral origins. Notably, group 1 CNS-PNETs encompassed several histologic classes including embryonal tumor with abundant neuropil and true rosettes (ETANTR), medulloepithelioma, ependymoblastoma and CNS-PNETs with variable differentiation. Strikingly, gene expression and methylation profiling analyses revealed a common molecular signature enriched for primitive neural features, high LIN28/LIN28B and DNMT3B expression for all group 1 CNS-PNETs regardless of location or tumor histology. Our collective findings suggest that current known histologic categories of CNS-PNETs which include ETANTRs, medulloepitheliomas, ependymoblastomas in various CNS locations, comprise a common molecular and diagnostic entity and identify inhibitors of the LIN28/let7/PI3K/mTOR axis and DNMT3B as promising therapeutics for this distinct histogenetic entity.

Fetus in fetu: a medical curiosity--considerations based upon an intracranially located case.

INTRODUCTION: "Fetus in fetu" (FIF) is defined as the abnormal monozygotic twin inside the body of its "host twin." Intracranial FIFs are extremely rare. CASE PRESENTATION: A male premature newborn was admitted to the hospital due to a large intracranial tumor diagnosed in the 31st week of gestation. The child died before surgical treatment because of failure of the respiratory system due to fetal respiratory distress syndrome. During general autopsy, a large intracranial tumor with four relatively well-developed limbs was found. Microscopically, apart from relatively well-formed musculoskeletal structures of limbs that were covered with skin, there were haphazardly distributed different tissues or fragments of organs. However, various neuroectodermal derivatives were dominant. CONCLUSION: We believe that intracranial FIFs, theoretically with poor prognosis, can be successfully curable in cases revealed prenatally, provided that optimal treatment is introduced and the achievement of proper pulmonary maturity of the host is accomplished prior to the operation of the tumor.

Torticollis as a first sign of posterior fossa and cervical spinal cord tumors in children.

BACKGROUND: Torticollis, despite being well-known neurological manifestation, is often underestimated as a first symptom of the abnormalities of posterior cranial cavity and cervical spinal cord. OBJECTIVES: The purpose of this study is to analyze the occurrence of acquired torticollis in children as a herald sign of the tumors of the cervical spinal cord or of the posterior fossa. METHODS: Clinical records of 54 cases treated for the tumor of the cervical spinal cord or posterior fossa (including congenital ones) were retrospectively reviewed. The following data were calculated: the occurrence of the torticollis as a first sign of tumors, the duration time from the onset of the symptoms to diagnosis, the concurrence of other pathological symptoms, and the diminishing of symptoms of the torticollis following treatment. RESULTS: In 12/54 (22.2 %) torticollis was first sign of central nervous system tumor and in all of them preceded other neurological symptoms. The time from the onset of torticollis to establishing diagnosis ranged from 2 to 52 weeks (9.6 weeks on average). Eleven of twelve patients were treated surgically--in 10 of them, torticollis disappeared in the postoperative course. CONCLUSIONS: Torticollis may be a herald sign of the tumor of the cervical spinal cord or the posterior fossa. Those pathologies should be considered in the differential diagnosis of the torticollis, particularly if accompanied by other symptoms of the focal pathology of central nervous system. Awareness of this fact may shorten the time to establish the proper diagnosis. Torticollis necessitates exclusion of the posterior fossa and spinal cord tumor.

Inactivation of heparin by cationically modified chitosan.

This study was performed to evaluate the ability of N-(2-hydroxypropyl)-3-tri methylammonium chitosan chloride (HTCC), the cationically modified chitosan, to form biologically inactive complexes with unfractionated heparin and thereby blocking its anticoagulant activity. Experiments were carried out in rats in vivo and in vitro using the activated partial thromboplastin time (APTT) and prothrombin time (PT) tests for evaluation of heparin anticoagulant activity. For the first time we have found that HTCC effectively neutralizes anticoagulant action of heparin in rat blood in vitro as well as in rats in vivo. The effect of HTCC on suppression of heparin activity is dose-dependent and its efficacy can be comparable to that of protamine-the only agent used in clinic for heparin neutralization. HTCC administered i.v. alone had no direct effect on any of the coagulation tests used. The potential adverse effects of HTCC were further explored using rat experimental model of acute toxicity. When administered i.p. at high doses (250 and 500 mg/kg body weight), HTCC induced some significant dose-dependent structural abnormalities in the liver. However, when HTCC was administered at low doses, comparable to those used for neutralization of anticoagulant effect of heparin, no histopathological abnormalities in liver were observed.

Degeneration and calcification of the cervical endplate is connected with decreased expression of ANK, ENPP-1, OPN and TGF-ß1 in the intervertebral disc.

The aim of this study was to clarify the relationship between the expression of ALP, ANK, ENPP-1, OPN and TGF-ß1 in the intervertebral disc (IVD), and cervical vertebral endplate calcification and degeneration. Sixty cervical IVDs were excised from 30 human cadavers. Each cadaver was assessed macroscopically for degeneration (Thompson's classification), and then underwent histological processing, regular staining (hematoxylin and eosin, Masson-Goldner trichrome and alcian blue-PAS), immunohistochemistry (ALP, ANK, ENPP-1, OPN and TGF-ß1), microscopic degeneration grading (Boos classification), and assessment of endplate calcification. The mean age ± SD of the cadavers was 51.4 ±19.5. The percentage of endplate calcification significantly correlated with the degree of endplate and IVD degeneration graded using Boos's score (both r = 0.91; p < 0.0001). The intensity and number of stained cells per FOV markedly decreased, for ANK, ENPP-1, and TGF-ß1, with the grade of IVD degeneration, regardless of the analyzed IVD region. This was not true only for ALP, which demonstrated an increasing trend corresponding to the degree of IVD degeneration. The expression of OPN was low throughout all analyzed regions, regardless of the degree of degeneration. Modulating the expression of the abovementioned proteins, especially ANK and TGF-ß1, may be a new way to prevent degeneration and calcification of the IVD.

Is development of high-grade gliomas sulfur-dependent?

We characterized γ-cystathionase, rhodanese and 3-mercaptopyruvate sulfurtransferase activities in various regions of human brain (the cortex, thalamus, hypothalamus, hippocampus, cerebellum and subcortical nuclei) and human gliomas with II to IV grade of malignancy (according to the WHO classification). The human brain regions, as compared to human liver, showed low γ-cystathionase activity. The activity of rhodanese was also much lower and it did not vary significantly between the investigated brain regions. The activity of 3-mercaptopyruvate sulfurtransferase was the highest in the thalamus, hypothalamus and subcortical nuclei and essentially the same level of sulfane sulfur was found in all the investigated brain regions. The investigations demonstrated that the level of sulfane sulfur in gliomas with the highest grades was high in comparison to various human brain regions, and was correlated with a decreased activity of γ-cystathionase, 3-mercaptopyruvate sulfurtransferase and rhodanese. This can suggest sulfane sulfur accumulation and points to its importance for malignant cell proliferation and tumor growth. In gliomas with the highest grades of malignancy, despite decreased levels of total free cysteine and total free glutathione, a high ratio of GSH/GSSG was maintained, which is important for the process of malignant cells proliferation. A high level of sulfane sulfur and high GSH/GSSG ratio could result in the elevated hydrogen sulfide levels. Because of the disappearance of γ-cystathionase activity in high-grade gliomas, it seems to be possible that 3-mercaptopyruvate sulfurtransferase could participate in hydrogen sulfide production. The results confirm sulfur dependence of malignant brain tumors.