Changes in spatial self-consciousness elicit grid cell-like representation in the entorhinal cortex

Grid cells in the entorhinal cortex (EC) encode an individual's location in space, integrating both environmental and multisensory bodily cues. Notably, body-derived signals are also primary signals for the sense of self. While studies have demonstrated that continuous application of visuo-tactile bodily stimuli can induce perceptual shifts in self-location, it remains unexplored whether these illusory changes suffice to trigger grid cell-like representation (GCLR) within the EC, and how this compares to GCLR during conventional virtual navigation. To address this, we systematically induced illusory drifts in self-location toward controlled directions using visuo-tactile bodily stimulation, while maintaining the subjects' visual viewpoint fixed (absent conventional virtual navigation). Subsequently, we evaluated the corresponding GCLR in the EC through functional MRI analysis. Our results reveal that illusory changes in perceived self-location (independent of changes in environmental navigation cues) can indeed evoke entorhinal GCLR, correlating in strength with the magnitude of perceived self-location, and characterized by similar grid orientation as during conventional virtual navigation in the same virtual room. These data demonstrate that the same grid-like representation is recruited when navigating based on environmental, mainly visual cues, or when experiencing illusory forward drifts in self-location, driven by perceptual multisensory bodily cues.

Numerosity estimation of virtual humans as a digital-robotic marker for hallucinations in Parkinson's disease

Hallucinations are frequent non-motor symptoms in Parkinson's disease (PD) associated with dementia and higher mortality. Despite their high clinical relevance, current assessments of hallucinations are based on verbal self-reports and interviews that are limited by important biases. Here, we used virtual reality (VR), robotics, and digital online technology to quantify presence hallucination (vivid sensations that another person is nearby when no one is actually present and can neither be seen nor heard) in laboratory and home-based settings. We establish that elevated numerosity estimation of virtual human agents in VR is a digital marker for experimentally induced presence hallucinations in healthy participants, as confirmed across several control conditions and analyses. We translated the digital marker (numerosity estimation) to an online procedure that 170 PD patients carried out remotely at their homes, revealing that PD patients with disease-related presence hallucinations (but not control PD patients) showed higher numerosity estimation. Numerosity estimation enables quantitative monitoring of hallucinations, is an easy-to-use unobtrusive online method, reaching people far away from medical centers, translating neuroscientific findings using robotics and VR, to patients' homes without specific equipment or trained staff.

Novel germline variants of CDKN1B and CDKN2C identified during screening for familial primary hyperparathyroidism

PURPOSE

CDKN1B mutations were established as a cause of multiple endocrine neoplasia 4 (MEN4) syndrome in patients with MEN1 phenotype without a mutation in the MEN1 gene. In addition, variants in other cyclin-dependent kinase inhibitors (CDKIs) were found in some MEN1-like cases without the MEN1 mutation. We aimed to describe novel germline mutations of these genes in patients with primary hyperparathyroidism (PHPT).

METHODS

During genetic screening for familial hyperparathyroidism, three novel CDKIs germline mutations in three unrelated cases between January 2019 and November 2021 were identified. In this report, we describe clinical features, DNA sequence analysis, and familial segregation studies based on these patients and their relatives. Genome-wide DNA study of loss of heterozygosity (LOH), copy number variation (CNV), and p27/kip immunohistochemistry was performed on tumour samples.

RESULTS

DNA screening was performed for atypical parathyroid adenomas in cases 1 and 2 and for cystic parathyroid adenoma and young age at diagnosis of PHPT in case 3. Genetic analysis identified likely pathogenic variants of CDKN1B in cases 1 and 2 and a variant of the uncertain significance of CDKN2C, with uniparental disomy in the tumour sample, in case 3. Neoplasm screening of probands showed other non-endocrine tumours in case 1 (colon adenoma with dysplasia and atypical lipomas) and case 2 (aberrant T-cell population) and a non-functional pituitary adenoma in case 3.

CONCLUSION

Germline mutations in CDKIs should be included in gene panels for genetic testing of primary hyperparathyroidism. New germline variants here described can be added to the current knowledge.

Changes of CD3+CD56+ γδ T cell number and apoptosis during hospital admission are related to mortality in septic patients

Immunoparalysis and apoptosis of T cells are serious problems for the evolution of septic patients. We aimed to relate changes in the number of αβ and γδ T cells during hospital stay to the poor evolution of sepsis. In this prospective study, we recruited a total of 92 septic patients from the Emergency and Intensive Care Departments of two Hospitals, according to the latest criteria for the definition and management of sepsis. According to the severity of the septic process, there was a progressive decrease in T cells, being much more intense in γδ T cells. This decrease recovered in surviving patients, but CD3+CD56+ γδ T cells continued to decreased during hospital stay in non-surviving patients. Apoptosis increased in sepsis. Cell death of CD3+CD56+ γδ T cells progressively increased according to the severity of sepsis, especially in non-surviving patients.

Animated virtual characters to explore audio-visual speech in controlled and naturalistic environments

Natural speech is processed in the brain as a mixture of auditory and visual features. An example of the importance of visual speech is the McGurk effect and related perceptual illusions that result from mismatching auditory and visual syllables. Although the McGurk effect has widely been applied to the exploration of audio-visual speech processing, it relies on isolated syllables, which severely limits the conclusions that can be drawn from the paradigm. In addition, the extreme variability and the quality of the stimuli usually employed prevents comparability across studies. To overcome these limitations, we present an innovative methodology using 3D virtual characters with realistic lip movements synchronized on computer-synthesized speech. We used commercially accessible and affordable tools to facilitate reproducibility and comparability, and the set-up was validated on 24 participants performing a perception task. Within complete and meaningful French sentences, we paired a labiodental fricative viseme (i.e. /v/) with a bilabial occlusive phoneme (i.e. /b/). This audiovisual mismatch is known to induce the illusion of hearing /v/ in a proportion of trials. We tested the rate of the illusion while varying the magnitude of background noise and audiovisual lag. Overall, the effect was observed in 40% of trials. The proportion rose to about 50% with added background noise and up to 66% when controlling for phonetic features. Our results conclusively demonstrate that computer-generated speech stimuli are judicious, and that they can supplement natural speech with higher control over stimulus timing and content.

Uncovering EEG Correlates of Covert Attention in Soccer Goalkeepers: Towards Innovative Sport Training Procedures

Advances in sports sciences and neurosciences offer new opportunities to design efficient and motivating sport training tools. For instance, using NeuroFeedback (NF), athletes can learn to self-regulate specific brain rhythms and consequently improve their performances. Here, we focused on soccer goalkeepers’ Covert Visual Spatial Attention (CVSA) abilities, which are essential for these athletes to reach high performances. We looked for Electroencephalography (EEG) markers of CVSA usable for virtual reality-based NF training procedures, i.e., markers that comply with the following criteria: (1) specific to CVSA, (2) detectable in real-time and (3) related to goalkeepers’ performance/expertise. Our results revealed that the best-known EEG marker of CVSA—increased α-power ipsilateral to the attended hemi-field— was not usable since it did not comply with criteria 2 and 3. Nonetheless, we highlighted a significant positive correlation between athletes’ improvement in CVSA abilities and the increase of their α-power at rest. While the specificity of this marker remains to be demonstrated, it complied with both criteria 2 and 3. This result suggests that it may be possible to design innovative ecological training procedures for goalkeepers, for instance using a combination of NF and cognitive tasks performed in virtual reality.

Low frequency of positive antithyroid antibodies is observed in patients with thyroid dysfunction related to immune check point inhibitors

INTRODUCTION

Immune checkpoint inhibitors (ICI), such as programmed death-1 inhibitors (anti-PD1), have become a cornerstone for the treatment of different advanced cancers. These antibodies act as modulators of immune checkpoint proteins. However, ICI can lead to the breaking of immune self-tolerance, inducing autoimmune side effects (irAEs), including endocrinopathies. One of the most frequent endocrine irAE of anti-PD1 is thyroid dysfunction, but the exact mechanism of this disease still remains unknown.

MATERIALS AND METHODS

We conducted a descriptive retrospective study, analyzing 11 patients who received at least one dose of anti-PD1 (nivolumab or pembrolizumab) and presented thyroid irAEs. Data were collected between September 2015 and May 2018 in our hospital. The aim was to analyze the clinically relevant features of thyroid irAEs and the frequency of antithyroid antibodies (ATA) positivity observed on them.

RESULTS AND DISCUSSION

8 of the 11 patients were treated with nivolumab and the other three patients received pembrolizumab. Six patients presented silent thyroiditis with a thyrotoxicosis phase; three patients developed directly primary/subclinical hypothyroidism and two patients showed primary hyperthyroidism. Thyroid autoantibodies (anti-Thyroglobulin and anti-Thyroid Peroxidase) were assessed in all the 11 patients, and only in two of them (18%) a positive titer was displayed. Anti-TSH receptor antibodies (TRAbs) were examined in five patients, three with painless thyroiditis at the time of thyrotoxicosis and two with primary hyperthyroidism, and they all had undetectable levels.

CONCLUSIONS

In our sample of 11 Caucasian patients with thyroid dysfunction related with anti-PD1, we found low frequency of ATA positive titers, comparable to other recent reports in others ethnicities, which could suggest that silent thyroiditis due to pembrolizumab or nivolumab has a different pathogenesis from the classical autoimmune spontaneous thyroiditis. Further investigations are required to completely understand the immune mechanisms involved.

P2749PCSK9 and HS-CRP are predictors of the progression of aortic stenosis in patients with stable coronary artery

Objective

There has been a great interest in knowing the factors associated with progression of aortic stenosis to try to slow down this evolution.

Methods

We studied 283 patients with chronic ischemic heart disease recording a broad number of clinical, therapeutic and analytical variables including inflammation and mineral metabolism biomarkers. We analyzed if any of these factors is a determinant of progression to aortic stenosis, defined as an increase in maximum flow speed across the aortic valve of at least 0.5 m/s.

Results

20 patients (7%) progressed to aortic stenosis in 72.4 months of follow-up. Among the patients who developed aortic stenosis, a greater age, greater percentage of peripheral arterial disease (PAD), lower treatment with beta-blockers, estimated Glomerular Filtration Rate (eGFR), total cholesterol, LDL, High-sensitivity C-reactive protein (HS-CRP), high-sensitivity troponin, N-terminal pro b-type natriuretic peptide and galectin 3 were found.

The results of the multivariate analysis showed that plasma levels of Proprotein convertase subtilisin/kexin type 9 (PCSK9) [OR: 0.668 per every increase in 100.000 μg/ml CI (0.457–0.977); p=0.038], HS-CRP [OR: 1.034 per every increase in 1 mg/dl CI (1.005–1.063); p=0.022], dyslipidemia [OR: 4.622 CI (1.285–16.618); p=0.019], PAD [OR: 9.453 CI (1.703–52.452); p=0.010], and eGFR [OR: 0.962 CI (0.939–0.986); p=0.002], remained a parameter with the ability to independently predict the progression of aortic stenosis

Conclusions

In patients with chronic ischemic heart disease, low PCSK9 and high HS-CRP plasmatic levels, low eFGR, PAD and dyslipidemia were independent predictors of progression of aortic stenosis. More studies are needed to investigate the relationships between the progression of aortic stenosis PCSK9 and inflammation.

Incidence and etiological mechanism of stroke in cardiac surgery

OBJECTIVE

We studied patients who had experienced a stroke in the postoperative period of cardiac surgery, aiming to analyse their progression and determine the factors that may influence prognosis and treatment.

METHODS

We established a protocol for early detection of stroke after cardiac surgery and collected data on stroke onset and a number of clinical, surgical, and prognostic variables in order to perform a descriptive analysis.

RESULTS

Over the 15-month study period we recorded 16 strokes, which represent 2.5% of the patients who underwent cardiac surgery. Mean age in our sample was 69 ± 8 years; 63% of patients were men. The incidence of stroke in patients aged 80 and older was 5.1%. Five patients (31%) underwent emergency surgery. By type of cardiac surgery, 7% of patients underwent mitral valve surgery, 6.5% combined surgery, 3% aortic valve surgery, and 2.24% coronary surgery. Most cases of stroke (44%) were due to embolism, followed by hypoperfusion (25%). Stroke occurred within 2 days of surgery in 69% of cases. The mean NIHSS score in our sample of stroke patients was 9; code stroke was activated in 10 cases (62%); one patient (14%) underwent thrombectomy. Most patients progressed favourably: 13 (80%) scored≤2 on the modified Rankin Scale at 3 months. None of the patients died during the postoperative hospital stay.

CONCLUSION

In our setting, strokes occurring after cardiac surgery are usually small and have a good long-term prognosis. Most of them occur within 2 days, and they are mostly embolic in origin. The incidence of stroke in patients aged 80 and older and undergoing cardiac surgery is twice as high as that of the general population.

Elektronenmikroskopische Sichtbarmachung von ≤ 10 A großen Fremdstoffeinschlüssen in elektrolytisch abgeschiedenen Nickelschichte mittels Phasenkontrast durch Defokussieren

Defokussierte elektronenmikroskopische Aufnahmen von Nickelschichten, die in Gegenwart organischer Fremdstoffadsorbate elektrolytisch abgeschieden wurden, zeigen starke Punktkontraste. Verschiedene elektronenoptische Beobachtungen, ergänzende spektralphotometrische Messungen und lichtoptische Modellversuche lassen den Schluß zu, daß die Punkte durch Phasenkontrast sichtbar gemachte einzelne Moleküle oder einige wenige Moleküle enthaltende Fremdstoffeinschlüsse sind.

Impaired endothelial function is not associated with arterial stiffness in adults with type 1 diabetes

AIM

This study investigated the relationship between endothelial dysfunction (ED) and arterial stiffness (AS) in adults with type 1 diabetes and no clinical cardiovascular (CV) disease.

METHODS

A total of 68 patients with type 1 diabetes and 68 age- and gender-matched healthy (non-diabetic) subjects were evaluated. ED was assessed by reactive hyperaemia peripheral arterial tonometry (RH-PAT) and by serum concentrations of soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1) and E-selectin. AS was assessed by aortic pulse wave velocity (aPWV). All statistical analyses were stratified by gender.

RESULTS

Adults with type 1 diabetes had RH-PAT index scores similar to those of their matching controls [men: 1.55 (1.38-1.98)% versus 1.61 (1.40-2.17)%, P=0.556; women: 2.07 (1.55-2.31)% versus 2.08 (1.79-2.49)%; P=0.215]. However, after adjusting for potential confounders, type 1 diabetes emerged as the main determinant of the RH-PAT index in women. Also, differences between genders in both the controls and type 1 diabetes patients disappeared. Men with diabetes had higher serum concentrations of E-selectin, and women had higher serum concentrations of sICAM-1, sVCAM-1 and E-selectin than their respective controls. However, after adjusting for potential confounders, only the differences in sICAM-1 (women) and E-selectin (both genders) remained significant. No association was found between aPWV and the RH-PAT index and ED markers after adjusting for CV risk factors.

CONCLUSION

ED was increased in adults with type 1 diabetes compared with age-matched non-diabetic subjects. Also, gender differences in ED were lost in type 1 diabetes. However, ED was not associated with AS after adjusting for potential confounders. These findings suggest that ED occurs earlier than AS in type 1 diabetes.

Psoriasis-associated genetic polymorphism in North Indian population in the CCHCR1 gene and in a genomic segment flanking the HLA-C region

Psoriasis is a common, chronic, recurrent, inflammatory, hyper proliferative disorder of the skin, which has a relatively high prevalence in the general population (0.6–4.8%). Linkage and association analyses in various populations have revealed a major locus for psoriasis susceptibility, PSORS1, at 6p21.3. Association of the disease with human leukocyte antigen (HLA) Cw6, corneodesmosin (CDSN) and the coiled-coil alpha-helical rod protein-1 (CCHCR1) has also been reported. Though the PSORS1 locus accounts for 30–50% of familial psoriasis in various global population groups, yet no studies have been published from the North Indian population. Some of the SNPs in HLA-C and CCHCR1 genes have been reported as markers for disease susceptibility. Therefore in the present study, DNA samples from psoriasis patients from North India were genotyped for polymorphisms in CCHCR1 and HLA-C genes. The allele frequencies were calculated for patients and controls, and were compared for odds ratio and confidence interval values. SNPn.7*22222 (rs12208888), SNPn.7*22333 (rs12216025), SNPn.9*24118 (rs10456057), CCHCR1_386 (rs130065), CCHCR1_404 (rs130076) and CCHCR1_1364 (rs130071) were found to be significant in psoriasis patients. Linkage disequilibrium analysis revealed two haplotypes (rs12208888, rs2844608, rs12216025, rs10456057, rs130065, rs130066, rs130068, rs130269, and rs12208888, rs2844608, rs12216025, rs130076, rs130066, rs130068, rs130269, rs130071) as highly susceptible haplotypes for psoriasis in the cohort studied. Preliminary analysis of the data also suggests the possibilities of ethnic group specific disease related polymorphisms, pending validation in future studies.

Exciton formation and annihilation during 1D impact excitation of carbon nanotubes

Near-infrared electroluminescence was recorded from unipolar single-wall carbon nanotube field-effect transistors at high drain-source voltages. High resolution spectra reveal resonant light emission originating from the radiative relaxation of excitons rather than heat dissipation. The electroluminescence is induced by only one carrier type and ascribed to 1D impact excitation. An emission quenching is also observed at high field and attributed to an exciton-exciton annihilation process and free carrier generation. The excitons' binding energy in the order of 270 meV for 1.4 nm SWNTs is inferred from the spectral features.

Formaldehyde and some fully n-methylated substances in boar seminal fluids. Short communication

On the basis of recent observations it is supposed that seminal fluids may contain--mainly in hydroxymethyl groups--formaldehyde (HCHO) and quaternary ammonium compounds as potential HCHO generators, therefore, preliminary investigations were carried out for the identification of these compounds in pig seminal fluids using OPLC, HPLC and MALDI MS techniques. The fresh pig seminal fluid was frozen in liquid nitrogen, powdered and aliquots (0.25 g) were treated with 0.7 ml ethanolic dimedone solution. The suspension was centrifuged and the clear supernatant was used for analysis by OPLC or after dilution with HPLC or MALDI MS technique. After OPLC separation of formaldemethone the fully N-methylated compounds which are stayed on the start point were separated by OPLC using an other eluent system. It has been established that the HCHO is really a normal component of the pig seminal fluid, as well. It can be isolated and identified in dimedone adduct form. The measurable amount of HCHO depended on the concentration applied of dimedone. According to OPLC and MALDI MS investigations L-carnitine is the main quaternary ammonium compound in pig seminal fluid which can generate a protection of the sperm cells against environmental and other influences. Considerable differences have been found among individuals concerning concentrations of quaternary ammonium compounds in the seminal fluid of pigs.

Characterization of germination with physical parameters: correlation of relative mass and density as an indicator function of the germination of European Turkey oak acorn

During germination of European Turkey oak acorn (Quercus cerris L.), a linear relationship was established between mass and density. Water take-up induced by osmotic pressure of imbibition was established to be independent of the volume of the acorn. Development of the germinating acorn can be characterized by its physical parameters of relative mass (the mass of the germinating acorn divided by its mass at the beginning of germination) and density. Linear correlation between the increment of relative mass and the decrease in density reveals an important property of the germinating acorn, namely that the slopes of the straight lines fitted to the data pairs of relative mass and density can statistically be considered as a constant. On the basis of this finding, the germinating acorns having the same values of relative mass and density can be grouped into the same developmental stage.

Pharmacogenomic analysis of rhIL-11 treatment in the HLA-B27 rat model of inflammatory bowel disease

Recombinant human interleukin-11 (rhIL-11) reduces the clinical signs and histological lesions of inflammatory bowel disease (IBD) in transgenic rats expressing the human major histocompatability complex (MHC) class I allele, HLA-B27. To elucidate the pharmacogenomic effects of rhIL-11 in this model, we examined the global gene expression pattern in inflamed colonic tissue before and following rhIL-11 treatment using oligonucleotide microarrays. In total, 175 disease-related genes were identified. Increased expression of genes involved in antigen presentation, cell death and inflammation, and decreased expression of metabolic genes was associated with disease. A total of 27 disease-related genes returned to normal expression levels following rhIL-11 treatment including the MHC class II gene RT1-DMbeta. rhIL-11 induced the expression of four intestinal epithelial growth factors. These gene expression patterns indicate that treatment of inflammatory bowel disease with rhIL-11 affects class II antigen processing and colonic epithelial cell proliferation and metabolism.

Subcutaneous or oral administration of rhIL-11 modulated the contact hypersensitivity response

Recombinant human interleukin 11 (rhIL-11) is a multifunctional cytokine with immunomodulatory activity on both T cells and macrophages. The effects of rhIL-11 in a murine model of contact hypersensitivity (CHS) response have been studied. The CHS response is a T cell-mediated response directed against chemically modified self-proteins following epidermal exposure to haptens. CHS is generated in two phases. The sensitization phase involves dermal dendritic cell recognition of haptenized proteins and antigen presentation. The effector phase involves T cell recognition and activation. In mice sensitized with oxazolone, CHS was induced by secondary challenge to the right ear and measured by ear swelling 24 h later. rhIL-11 significantly suppressed CHS as measured by ear swelling and tissue myeloperoxidase activity when injected subcutaneously for 5 days from the day of sensitization or when administered only on the day before and the day of challenge, but was not effective when administered prior to or on the day of sensitization. These results indicate that subcutaneously administered rhIL-11 may modulate the effector phase of CHS. Administration of rhIL-11 as an oral gavage prior to sensitization also reduced CHS. However oral administration of rhIL-11 after sensitization had no effect. These results suggest that orally and subcutaneously administered rhIL-11 may act through different mechanisms to affect CHS.

Serial renal biopsy in systemic lupus erythematosus

OBJECTIVE

To examine the role of sequential renal biopsies in patients with systemic lupus erythematosus (SLE), with regard to indications, morphologic change over time, and the clinical utility of repeat biopsies.

METHODS

Patients with repeat renal biopsies were identified from the University of Toronto Lupus Clinic Database and their biopsies were reviewed blindly by a committee, using the WHO classification as well as activity and chronicity indices. Reasons for obtaining biopsy were documented, and therapeutic decisions following repeat biopsy were tabulated.

RESULTS

Fifty-seven patients (49 F/9 M) had at least 2 renal biopsies between 1970 and 1994. The mean interval between biopsies was 4.2 years. The major reason for obtaining the first biopsy was disease diagnosis (32/57), while the majority of repeat biopsies were performed to discern the cause of increasing proteinuria (45/57). A comparison of the WHO classification of initial and repeat biopsies showed evolution to another class in 23 instances, but more commonly a change within a class was seen. A decrease in proliferative lesions (classes III and IV and subsets of V) was noted on repeat biopsies. The chronicity index increased significantly (p = 0.0001) and the activity index decreased (p = 0.064) between biopsies. Seventy-seven percent of patients had a change in treatment based on biopsy results.

CONCLUSION

The major reason for repeat renal biopsy in patients with SLE was proteinuria. Renal morphology in patients with SLE can change with time, particularly in terms of chronicity and activity features. Repeat biopsies in patients with SLE appear to have clinical utility.

HPLC-OPLC-MS investigation of change of formaldehyde and its generators in human teeth of different physiological stage

Taking into consideration the unquestionable intracellular occurrence of formaldehyde (HCHO) and its generators in cells of plant, animal and human organisms as well as in body fluids it was resolved to determine their levels in hard tissues of physiologically and pathologically changed teeth. The aim of the work was to determine the relationship between the level of HCHO and the levels of its generators in pathologically changed teeth, mainly carietic teeth as tooth caries is still a serious and commonly occurring problem. The occurrence of HCHO (captured as its dimedone adduct) and some of its potential generators was demonstrated in the hard tissues of healthy and pathological human teeth by means of OPLC, HPLC and MS analyses. It was established that the measurable level of HCHO was increased in the carietic teeth in comparison with healthy ones. In the case of paradontic tooth sample, a dramatic increase of HCHO was observed and at the same time the level of betaines was decreased considerably. The obtained results give a new insight into the pathology of hard tissues of teeth in strong correlation with the phases of stress syndrome.

Identification and measurement of resveratrol and formaldehyde in parts of white and blue grape berries

The phytoalexin resveratrol (3,5,4'-trihydroxy-trans-stilbene) and formaldehyde (as its dimedone adduct, formaldemethone) have been identified and measured in the extracts of parts of white and blue grapes as well as in white and red wines by overpressured layer chromatography (OPLC), high performance liquid chromatography (HPLC) and from matrix assisted laser desorption/ionization mass spectrometric data. It has been established that the level of resveratrol was very high in skin and in some cases in the stem. Blue grape varieties and red wines always contained a considerably higher amount of resveratrol than white grapes and wines. The measurable level of formaldehyde as well as the resveratrol content was always parallelly high in the same parts of the berries, however, the formaldehyde level was higher in white grapes than in blue ones. The simultaneous occurrence of resveratrol and formaldehyde gives a possibility for interaction between these two special molecules, consequently, hydroxymethyl derivatives of resveratrol can be formed. These resveratrol derivatives may be responsible for special biological activities of resveratrol in grapes and dietetically (cardioprotective effect and chemopreventive effect against cancer) in the human organism.

Alteration of endogenous formaldehyde level following mercury accumulation in different pig tissues

The effect of mercury accumulation on the formaldehyde cycle of different pig tissues resulted by a single dose of mercury (0.4 mg mercury in Hg(II)-chloride form, 500 kBq Hg-203/animal) has been studied. Daily mercury excretion was tracked, and having reached the steady-state mercury level of the body (10th day), samples were taken from the liver, kidney and muscle (musculus longissimus dorsi). After reaction with dimedone the endogenous formaldehyde levels in the samples were measured by high performance liquid chromatography. Our results show that the endogenous formaldehyde level decreased by more than 50% in the liver and the kidney, where the average mercury accumulation was the highest (1017 Bq/100 g and 625 Bq/100 g, respectively). In contrast, the muscle tissues, with a low mercury level (139 Bq/100 g), responded to the stress effect by about a 30% increase in their endogenous formaldehyde level.

The effect of heat shock on the formaldehyde cycle in germinating acorns of European Turkey oak

The effect of heat shock (40 degrees C) on the formaldehyde cycle has been studied in European Turkey oak (Quercus cerris L.) acorns germinated to a 10% increase in mass. Hydroxy-methyl groups bonded to sulfur, oxygen and nitrogen atoms were made to react with dimedone and the derivative obtained (formaldemethone), which represented the endogenous formaldehyde level, was determined by high performance liquid chromatography. Qualitative alterations of methyl donors and acceptors in the response of acorns to the heat shock have been mapped by MALDI (matrix assisted laser desorption ionization) mass analysis. In the first experiment the acorns were prevented from withering by wrapping them in aluminium foil and in the second they were not. The relatively high temperature of the acorns wrapped in aluminium foil was the dominant stress effect and the role of withering was subsidiary. Alteration of the endogenous formaldehyde level in the seed-leaves reflected the phases of the stress syndrome. If the withering were not hindered, two local minima in the alteration of endogenous formaldehyde level were found. First, the increase in temperature decreased the endogenous formaldehyde level and after a local maximum a repeated local minimum was observed as a delayed response. It is presumed that the second minimum was induced by the decreasing water amount becoming more and more significant in the seed-leaves.

Formaldehyde cycle and the natural formaldehyde generators and capturers

S-adenosyl-L-methionine serves as a methyl donor in virtually all of the vast number of enzymatic transmethylation reactions including DNA methylation. On the basis of our former experiences we questioned the formation of a methyl cation or methyl radical in the enzymatic transmethylation reactions. The formation of formaldehyde from the methyl moiety of S-adenosyl-L-methionine has been demonstrated. It became increasingly evident that there is a formaldehyde cycle in biological systems in which the formation of the methyl group of L-methionine takes place through formaldehyde and the formation of formaldehyde from S-adenosyl-L-methionine is linked to different enzymatic transmethylation reactions. It is also known that during demethylation processes both formaldehyde and demethylated compound can be formed. The abnormalities of the originally controlled formaldehyde cycle and the uncontrolled enzymatic production of formaldehyde from endogenous and/or exogenous substrates may be potential risk factors in pathogenesis of different disorders. The formaldehyde generator and capturer molecules may potentially normalise these abnormal processes. Trans-resveratrol (trans-3,5,4'-trihydroxystilbene), which is as phytoalexin, occurs naturally in grapes and a variety of medicinal plants. According to our present observations it is a natural concentration-dependent formaldehyde capture molecule. It would seem that elimination of the uncontrolled formaldehyde with resveratrol may exert a double effect in biological systems. The elimination of formaldehyde with resveratrol (first step) may cause a cardioprotective effect and the reaction products between resveratrol and formaldehyde (second step) may act as a chemopreventive factor against cancer.

Plant tissue culture as a model for study of diversity in formaldehyde binding

The effect of endogenous formaldehyde (HCHO) deprivation with dimedone - as abiotic stress - was investigated on the methylation-demethylation reactions in Datura innoxia Mill. callus cultures. The matrix assisted laser desorption/ionization mass spectrometric (MALDI MS) investigation of the culture extracts revealed characteristic differences between the tissues cultivated in light and dark. MALDI MS data show the presence of a precursor molecule and its mono- and tri-hydroxymethyl derivative, only in the cultures maintained in light. The relative amount of the different derivatives changed considerably, as a consequence of dimedone application in the culture medium and during the extraction.

Changes in formaldehyde contents of germinating acorns of Quercus cerris L. under low temperature stress conditions

Acorns of Quercus cerris L., after saturation with water and storage at -20 degrees C, were studied for changes in their contents of endogenous formaldehyde and its potential precursor and generator compounds. For the measurement of formaldehyde, after conversion to formaldemethone and some methyl acceptor and donor substances, high performance liquid chromatography (HPLC) were used. First, the amount of formaldehyde was drastically decreased. Having reached a minimum value within three to five days of the beginning of low temperature storage, a higher steady-state than the control acorns was recorded. Trigonelline and gamma-amino-butyric acid in seedleaf extracts were identified by matrix assisted laser desorption-ionization mass spectrometry (MALDI-MS).

Study of enzyme-catalysed polymerization of lactic acid by HPLC and MALDI-MS

The enzyme-catalysed polymerization of lactic acid was tested by HPLC and MALDI-MS methods. A chiral HPLC technique was applied to the investigation of the enantio-selectivity of the reaction. The polymer compounds formed were identified by MALDI-MS.

Molecular effects of recombinant human interleukin-11 in the HLA-B27 rat model of inflammatory bowel disease

Recombinant human interleukin-11 (rhIL-11) is a pleiotropic cytokine with effects on multiple cell types. In addition to thrombopoietic activity, rhIL-11 has demonstrated anti-inflammatory activity in vitro and in vivo. rhIL-11 treatment reduces clinical signs and histologic lesions of colitis in transgenic rats expressing the human major histocompatibility complex (MHC) Class I allele, HLA-B27. We have investigated the effects of rhIL-11 at the molecular and cellular level in this model of inflammatory bowel disease. RT-PCR analysis of colonic RNA revealed that treatment with rhIL-11 down-regulated expression of proinflammatory cytokines including TNF-alpha, IL-1beta, and IFN-gamma. rhIL-11 also reduced the level of myeloperoxidase activity in the cecum indicating reduced inflammation. After stimulation in vitro with anti-CD3 antibody, spleen cell cultures derived from rhIL-11-treated rats produced less IFN-gamma, TNF-alpha, and IL-2 than cultures derived from vehicle-treated rats. These molecular and cellular effects correlated with amelioration of disease as measured by stool character and histologic lesion scores. These findings suggest that rhIL-11 acts to reduce inflammation through modulation of multiple proinflammatory mediators including products of activated T cells. This study has identified pharmacodynamic markers of rhIL-11 anti-inflammatory activity in vivo and supports rhIL-11 therapy to treat inflammatory bowel disease.

Cryocrystalglobulinemia mimicking rheumatoid arthritis and vasculitis

We describe a patient with longstanding arthropathy resembling rheumatoid arthritis (RA) and cold induced purpura for many years, concomitant with IgG kappa paraproteinemia. At autopsy, the patient was found to have evidence of widespread vascular occlusions due to precipitated crystals as well as tissue deposition of crystals. Neither vasculitis nor synovitis was observed despite the clinical picture of both. Blood and synovial fluid obtained antemortem were found to spontaneously form crystals when stored at 4 degrees C, and the washed crystals were composed of the same monoclonal IgG kappa previously found in serum. Cryocrystal formation occurred at 33 degrees C and neutral pH. This patient thus had cryocrystalglobulinemia mimicking clinical manifestations of RA and vasculitis.

Regulation of human immunodeficiency virus env expression by the rev gene product

A single simian virus 40 late replacement vector which expresses both the rev and envelope (env) genes of human immunodeficiency virus was used to examine the mechanism underlying the dependence of env gene expression on the rev protein. When rev was deleted from the vector, no envelope protein expression could be detected in transfected cells, and the levels of cytoplasmic env mRNA were dramatically reduced. In contrast to this, the levels of env RNA in total cellular RNA preparations were similar with or without rev coexpression, and analysis of nuclear RNA showed that the levels of nuclear env RNA were increased in the absence of rev. These results suggest that rev functions to regulate nuclear export of env mRNA. It was possible to restore env expression from the vector lacking rev by supplying rev in trans, provided that a cis-acting sequence was also present. This sequence was mapped to a 854-base-pair region within the env open reading frame, and it was shown that the sequence could be moved but that it worked only in its original orientation.

[Behavior of serum zinc and selected plasma proteins following urologic operations]

In order further to contribute to the clarification of the serum-zinc level after larger abdominal urological interventions in 30 patients, in whom a supravesical derivation of the urine became necessary, serum-zinc determinations were performed twice preoperatively as well as on the 1st, 7th, 14th and 21st postoperative day. At the same time the proteins transferrin, coeruloplasmin and haptoglobin were determined in the serum. In other 45 patients who for a longer period lived with a supravesical derivation of the urine (uretero-intestinal anastomosis/ileum conduit) repeatedly serum-zinc determinations were performed, in order to establish a possible influence of the long-term urine derivation into the intact or excluded intestine on the serum-zinc content. On the 1st postoperative day a clear decrease of the serum zinc level by on an average 23% of the initial value were found. Coeruloplasmin and haptoglobin reacted with an increase of concentration. After a long-term derivation of the urine into the intact or excluded intestine normal serum-zinc concentrations were found.

[Experiences with transparenchymal coral calculi removal under local hypothermia]

Under certain conditions genuine coral calculi are an absolute offication for nephrotomy. In order to achieve complete hygienization of the cavity ischaemia times of more than 25-30 min are often necessary. Controlled surface cooling proved to be very good for improving ischaemia tolerance and reducing post-ischaemic loss of function in 21 necessary nephrotomies out of a total of 651 operations for concrements in the calyx system of the renal pelvis (= 3.2%; = 32.8% of all nephrotomies). A kidney thermometer with a temperature feeler developed by us allows fine control of the hypothermia induced by means of plastic bags filled with ice crystals. The technique of operation together with its advantages and disadvantages are described.

[Behavior of the mucosa of the large intestine following definite urinary diversion]

Multiple biopsies of the mucous and submucous membranes were taken from 50 patients with definitive diversion of urine using the large intestine and evaluated. The varying behaviour of the membranes in connection with uretero- sigmoidostomies , cysto- sigmoidostomies and rectal bladders is discussed. The reactions of the mucous membrane in connection with uretero-intestinal anastomosis are time-dependent. The most serious changes in the mucous membrane occurred in connection with rectal bladders.