P–105 Clinical validation of mojo AISA, an artificial intelligence robotic CASA system

Study question

Can a CASA system based on Artificial Intelligence perform as well as manual semen assessment, within the WHO error margins?

Summary answer

The AI-based CASA systems that mimic high quality assessments show great potential for reducing clinical workloads while increasing treatment efficacy.

What is known already

The field of male-factor fertility investigation is still lacking an automated semen analysis system that can be widely clinically adopted. By leveraging state-of-the-art robotics and Artificial Intelligence (AI), it was possible to build mojo AISA which is an AI and robotic platform designed according to WHO recommendation for semen analysis. This system is based on AI software with a unique convolutional neural network (CNN) that detects and measures sperm concentration and motility while ruling out unwanted cells and debris in raw samples.

Study design, size, duration

This study presents and validates the mojo AISA device. A total of 60 patient samples at ANOVA Karolinska University Hospital were collected and results from manual assessment were compared to mojo AISA for concentration and motility. Semen samples were assessed manually (WHO 2010) and concurrently with Mojo AISA. Manual measurements ranged from 1–206M/ml. This study lasted from May 2020 to December 2020 following informed consent and ethics committee practices of ANOVA.

Participants/materials, setting, methods

Sample preparation protocol for mojo AISA consisted of placing two 10ul drops and covering with two 22x22mm coverslip. Manual assessment followed ANOVA EQA procedures akin to the WHO. A CNN was trained using videos captured with mojo AISA as input data. Images were annotated to form a validation set by which the AI was trained. To account for sampling error, videos of Hamilton Thorne Accubeads+ were captured using mojo AISA and the mojo counting chambers.

Main results and the role of chance

Comparing the concentration measured by mojo AISA with the known value for each microbead, results are in agreement of 86%, within the confidence interval of the microbeads. The mean relative error was 6.7% and maximum error was 11%. Therefore, Accubeads+ validation proved no observational error regarding the use of mojo AISA microscope. As for comparing mojo AISA to manual assessment for concentration, Pearson (Spearman) correlation was 0.95 (0.97). The mean relative error was 24.8% and maximum relative error was 71.1%, where 90% of samples were below 50% error. By looking at the concentration range between 10 and 20 M/ml, mojo AISA displayed a mean error of 18.5%. For motility, as comparing mojo AISA to manual assessment, a result of 35.4% mean relative error was obtained. To conclude, mojo’s robotic solution shows promise for clinical practice as the AI continues to improve. In 6 months, sperm concentration correlation improved by 3-fold. Next, the AI will be further clinically trained for low concentration.

Limitations, reasons for caution

mojo AISA requires further development, especially for very low concentration ranges, below 5M/ml, due to high sensibility to false positive detections. The same applies to post-vasectomy samples. Additionally, the necessity to compute the motility of each sperm scales poorly with high concentration generating a poor experience for high volume clinics.

Wider implications of the findings: Automation is crucial in several industries. It enables fertility clinics & andrologists to standardize male factor infertility measurements (if paired with widespread standardization of protocols for automation) while enabling them to put more focus on demanding activities of their profession and removes human biases of inter-laboratory performance.

Trial registration number

Not applicable

P–123 How to develop accurate Computer Assisted Sperm Analysis (CASA) AI in the absence of protocol standardization and abundance of human error when performing semen analyses?

Study question

How can an automation & artificial intelligent tools be developed to perform according to WHO recommendations?

Summary answer

Developing CASA performs at < 20% error margin requires AI trained with high quality datasets and a robotic system adheres to WHO guidelines.

What is known already

A survey of 40 andrology laboratories, in 22 countries, revealed that > 90% had nonconformities in correct use of equipment, standardisation of protocols and quality control, leading to a lack of compliance to WHO protocols. Conventional CASA systems can standardize analysis, but controversy has occurred due to differences between manual and automated analyses stemming from: 1) all cells in a semen sample are detected including debris; 2) protocol variation when compared to top-notch manual analysis. The first point can be addressed by AI. The second point can be addressed by robotics designed to adhere to WHO guidelines.

Study design, size, duration

A mojo AISA (AI-powered semen analysis) system was placed in four clinical laboratories mentioned above capturing images of over 300 samples, one million images were generated over a course of 2 years. Mojo AISA’s AI was trained on data collected from the four clinics using robotic system is developed according to WHO guidelines.

Participants/materials, setting, methods

For an AI to detect sperm accurately, sperm samples were captured using mojo AISA smart microscopy and then the extracted sperm images expertly annotated. To evaluate the system-ability for semen analysis, fresh sample were analysed for concentration and motility by a manual operator and compared to a mojo AISA test.

Main results and the role of chance

To train the sperm detection AI, representative sperm images were carefully captured using mojo AISA and processed according to the following criteria: the number of images and videos to train and to test the model: 50,000 spermatozoon head and tails with various variations the variety of images: data used to train the AI has to be representative of the population that will undergo the analysis: 1) wide concentration ranges from 0 to 300 M/ml, 2) high and low density of debris and cells, 3) Presence of slight aggregations careful and precise annotation: expert andrology scientists annotated sperm images and identify objects to exclude, such as debris in seminal plasma, Mojo AISA is an attempt strictly build CASA AI system to WHO-guidelines. The marriage of AI and robotics automation has shown a promising results to mimic humans when measuring a semen sample and attempt to obtain results comparable to the manual analysis.

mojo AISA’s performance improved three-fold (from 0,85 to 0,95 Pearson sperm count correlation and from >100% means relative error to 25% mean relative error).

Limitations, reasons for caution

Lack of standardization for semen analysis laboratory process globally is a bottleneck towards building a robust multi-center study, on-site CASA testing and generating an actionable data pool for studying the causes behind male fertility declineWider implications of the findings: Key learnings for parties advancing developing AI based on images and videos for application in the fertility space.

Trial registration number

Not applicable

Anagrelide influences thrombotic risk, and prolongs progression-free and overall survival in essential thrombocythaemia vs hydroxyurea plus aspirin

OBJECTIVE

We report an extension study of patients with essential thrombocythaemia (ET) in the Hungarian Myeloproliferative Neoplasm (HUMYPRON) Registry, which demonstrated that over 6 years anagrelide significantly decreased the number of patients experiencing minor arterial and minor venous thrombotic events (TEs) vs hydroxyurea+aspirin.

METHODS

Data on patients with ET were collected through completion of a questionnaire developed according to 2008 WHO diagnostic criteria and with regard to Landolfi, Tefferi and IPSET criteria for thrombotic risk. Data were entered into the registry from 14 haematological centres. TEs, secondary malignancies, disease progression and survival were compared between patients with ET treated with anagrelide (n = 116) and with hydroxyurea+aspirin (n = 121).

RESULTS

Patients were followed for (median) 10 years. A between-group difference in the number of patients with TEs was observed (25.9% anagrelide vs 38.0% hydroxyurea+aspirin; P = .052). Minor arterial events were more frequently reported in the hydroxyurea+aspirin group (P < .001); there were marginally more reports of major arterial events in the anagrelide group (P = .049). TE prior to diagnosis was found to significantly influence TE incidence (P > .001). Progression-free survival (P = .004) and survival (P = .001) were significantly increased for the anagrelide group vs hydroxyurea+aspirin.

CONCLUSIONS

Anagrelide reduced TEs, and increased progression-free and overall survival vs hydroxyurea+aspirin over (median) 10 years.

Anagrelide reduces thrombotic risk in essential thrombocythaemia vs. hydroxyurea plus aspirin

OBJECTIVE

To evaluate the reduction in thrombotic events (TE) in patients with essential thrombocythaemia (ET) treated with anagrelide versus hydroxyurea + aspirin (HU + ASA).

METHODS

A questionnaire was developed using 2008 WHO diagnostic criteria, and thrombotic risk factors were stratified according to Landolfi criteria. Through questionnaire completion, clinicians at Hungarian haematological centres entered data into the Hungarian MPN Registry on patients with myeloproliferative neoplasms. Based on ET registry data, TEs in anagrelide-treated patients (n = 139) were compared with HU + ASA-treated patients (n = 141).

RESULTS

Patients were followed up for (median) 6 yr. TEs were reported in significantly fewer anagrelide-treated patients versus HU + ASA (15.1% versus 49.6%; P < 0.001). Numbers of major arterial and major venous events were similar between the groups, although there were over fivefold more minor arterial and minor venous events in the HU + ASA group (P < 0.001). While median age at diagnosis was older and length of follow-up shorter in the HU + ASA group (P < 0.05), this did not influence TE incidence; medication and TE before diagnosis only influenced TE incidence.

CONCLUSIONS

Anagrelide significantly decreased the number of patients experiencing minor arterial and minor venous TEs versus HU + ASA over 6 yr. Risk of TE after diagnosis was significantly increased if the patient had TE before diagnosis.

Prognostic value of interim and restaging PET/CT in Hodgkin lymphoma. Results of the CHEAP (Chemotherapy Effectiveness Assessment by PET/CT) study - long term observation

Very few studies have determined the prognostic value of interim and restaging PET/CT in patients with Hodgkin lymphoma using current standard of care therapy outside clinical trials. We analyzed the effect of the results of interim and restaging PET/CT on the survival (overall- and relapse-free) in patients who received standard first-line treatment based on the stage of disease and risk factors. We investigated the differences between the relapse and non-relapse groups based on the clinical pathological characteristics of patients who had positive interim PET/CT results.Between January 1, 2007 and December 31, 2011, the staging, interim and restaging PET/CT scans of patients with Hodgkin lymphoma were analyzed. The Deauville criteria were used for the evaluation of interim PET/CT scans. One hundred and thirteen Hodgkin lymphoma patients underwent staging, interim and restaging PET/CT scans. None of the therapy was modified based on the interim PET/CT results. The median follow-up time was 43.5 months. A total of 62 early stage patients and 51 advanced stage patients were identified. The five-year overall survival rates were 93.4% in the interim PET negative group and 58% in the interim PET positive group (p<0.001). The five-year relapse-free survival rates for the negative and positive groups were 92.7% and 40.8%, respectively (p<0.001). The negative predictive value was 100% in the early stage group and 82.35% in the advanced stage group. By comparison, the positive predictive values were 53.8% and 58.8%, respectively, in these two groups. In the interim PET positive group, patients over 40 years of age had a significantly higher probability of relapse (p=0.057).The routine clinical use of interim PET/CT is highly recommended based on our investigation. However, patients with positive interim PET/CT results required frequent additional evaluations.

Prognostic value of FDG-PET in Hodgkin lymphoma for posttreatment evaluation. Long term follow-up results

Determining the viability of residual tumor masses is a great challenge after primary treatment of Hodgkin lymphoma. FDG-PET may play a crucial role in this procedure. In this study, files of 128 Hodgkin lymphoma patients were reviewed, who were treated in three Hungarian hematology centers between January 1995 and February 2005. CT scan showed residual tumor mass by all of them. Their median follow-up was 75.5 months from PET examination. The number of true-positive, true-negative, false-positive, false-negative subjects were 29, 83, 10, 6, respectively. Sensitivity of post-treatment FDG-PET was 83 %, specificity 93 %, positive predictive value 74 %, negative predictive value 93 %, and accuracy 88 %. The difference between the event free survival of PET positive and negative cases is highly significant (p=0.0000), according to the Mantel-Cox test. Our results in the largest cohort of patients, in accordance with literature, clearly indicates that patients with negative FDG-PET results are unlikely to progress or relapse during the longest follow-up.

Epidural malignant lymphomas of the spine: collected experiences with epidural malignant lymphomas of the spinal canal and their treatment

STUDY DESIGN

Retrospective study of 13 patients treated by the authors.

OBJECTIVE

To examine the course of the disease of malignant lymphoma (ML) presenting in the epidural area of the spine.

SETTING

Department of Neurosurgery, Third Department of Internal Medicine, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary.

SUBJECTS AND METHODS

The epidural presentation in eight patients was heralded by motor signs (paraparesis and plegia), in one by a lesion of the posterior columns of the spinal cord (ataxia), and in three by pain. One patient was free of complaints and symptoms. The affected epidural area was diagnosed previously by myelography and computerized tomography (CT), and later by magnetic resonance (MR), over the course of which the location was verified as thoracic in eight patients, cervical in one, and lumbar in four. The authors recommended surgical intervention in 9 out of 13 cases, in seven cases of Hodgkin's and six cases of non-Hodgkin's lymphoma. Seven patients were treated for recognized manifestations of malignant lymphoma while six were diagnosed by intraoperative-histological examination.

RESULTS AND CONCLUSION

The decompression operations for tumors resulted in limited improvement in seven patients (reduction in pain and return of ability to walk). Four patients were not operated on, two of which had significant improvement in their neurological symptoms. Paraparesis remained unchanged in one patient. One patient remained symptom-free. The authors emphasize the importance of interdisciplinary consultation and weighing individual priorities in the indications for operation on epidural ML.

"False" thymine-1H-Enol guanine base pair. low misinsertion rate by DNA polymerase explained by computational chemistry consideration

Formation of correct TA and GC and "false" thymine-1H-enol guanine (TGenol) base pairs is here considered to control nucleotide insertion into DNA via low substrate concentration Michaelis-Menten controlled kinetics. Contributions of base pairing to formation of Gibbs free energies in water solution, DeltaDeltaG, are calculated for the correct and false base pairs with the semi-empiric MNDO/PM3 method for base pairing energies in vacuum and the BEM method for hydration effects. The results for DeltaDeltaG indicate equal insertion rates for correct base pairing and a 10(-3)-10(-4) error probability for false insertion controlled by the TGenol false pair.

Investigation of monoclonal gammopathy of undetermined significance: a single-centre study

Summary The main characteristic of monoclonal gammopathies (MG) is the presence of an increased amount of both electrophoretically and immunologically homogeneous immunoglobulins (M component). According to the WHO classification, monoclonal gammopathies are classified among the non-Hodgkin's lymphomas as 'plasma cell dyscrasias'. The unknown behaviour state, so-called MGUS (monoclonal gammopathy of undetermined significance), is distinguished from the malignant diseases. We investigated the frequency and features of MG and MGUS by reviewing the serum immunochemistry protein analyses between 1998 and 2004. Among 18,642 analyses, MG was found in 1,983 cases (10.39%) derived from one or more samples of 416 patients. Case histories of 340 patients were analysed. A malignant lymphoproliferative disease was proved in 171 cases, while in 169 cases the behaviour of the gammopathy was unknown. In 65 cases, the disease was possibly not related to MG. Mean follow-up time of the 65 patients with MGUS was 42 (9-81) months. During the follow-up period seven patients progressed into a malignant lymphoproliferative disorder-- mean probability of the malignant transformation was 3.07%/year and it occurred more frequently in the presence of immunoglobulin A isotype. There was no correlation between the progression of the disease and other laboratory findings. Besides the analyses of MG-related diseases, we focus on the malignant transformation of MGUS and on the importance of regular clinical and laboratory control examinations.

Quantitative and qualitative approach of glycan-glycan interactions in marine sponges

Cell recognition and adhesion involving many kinds of cell surface molecules operate via homotypic and/or heterotypic protein-protein and protein-carbohydrate binding. Our investigations in marine sponges have provided direct evidence for a novel molecular mechanism of multivalent glycan-glycan binding related to cellular interactions. Biochemical characterization of purified proteoglycans revealed the presence of specific acidic glycans, different from classical glycosaminoglycans. Such acidic glycans of high molecular weight, containing fucose, glucuronic or galacturonic acids, and pyruvate and sulfate groups may represent a new class of primordial proteoglycans, named by us glyconectins. The thermodynamic and kinetic approaches of biological macromolecule interactions do not provide a direct measurement of the intermolecular binding forces that are fundamental for the function of the ligand-receptor association. Using the atomic force microscopy (AFM), we provided the first quantitative evaluation of the binding strength between cell adhesion proteoglycans. Measurement of binding forces intrinsic to cell adhesion glyconectin proteoglycans (AGPs) is necessary to assess their contribution to the maintenance of the anatomical integrity of multicellular organisms. (i) As a model, we selected the cell AGP isolated from the marine sponge Microciona prolifera; it mediates in vivo cell recognition and aggregation via homotypic, species-specific, multivalent, and calcium ion-dependent glycan-glycan interactions. (ii) Under physiological conditions, a large cohesive force theoretically able to hold the weight of approximately 1600 cells was measured. (iii) The C-2 autocomplementarity model for AGP-AGP interactions; and (iv) the requirement of the calcium ionic bridges suggest also that the self-recognition and multivalency of glycan-glycan interactions are essential for cell adhesion. (v) The evolution of glyconectin-like proteoglycan molecules may have been a fundamental prerequisite for the emergence of the first multicellular organisms. Glycan-glycan interactions may thus provide a new paradigm for molecular self-recognition.

Steric and electrostatic effects in dye-cellulose interactions by the MTD and CoMFA approaches

This paper presents the application of the MTD (minimal steric difference) analysis and CoMFA (comparative molecular field analysis) to series of anthraquinone vat, mono and disazo and disperses dyes with known affinities for cellulose fiber. A comparison of the results demonstrates that these methods usually agree with the prediction of structural features favorable for dyeing. A series of n = 49 anthraquinone vat dyes was studied by MTD with r2 between 0.903 and 0.941 and r2CV values in the range of 0.827-0.878. For CoMFA, r2 = 0.992, r2CV = 0.841 were obtained; the CoMFA field is in rather good agreement with vertex attributions, by MTD for attractive and repulsive vertices. Anionic disazo dyes were studied by the CoMFA method (n = 21, r2 = 0.999, r2CV = 0.703). Monoazo dyes (several series) were studied by CoMFA and MTD. The effect of lipophilicity on dye fiber affinity was, also, studied for these dyes. Disperse dye adsorption was analyzed by MTD and CoMFA (n = 27, r2 = 0.925, r2CV = 0.776). Conclusions refer to the effect of structural features of dye molecules upon adsorption on cellulose fibers.

Significance of MTD and other descriptors in lipophilicity models for chlorinated aromatic compounds

The lipophilicity of chlorinated benzenes and 20 biphenyls has been modeled using the minimum topological difference method and MTD indices. The MTD descriptor has been optimized on its own or together with nCl (number of chlorine atoms per molecule), 2D- and 3D-descriptors such as van der Waals surface area and volume, solvent accessible surface area and solvent-accessible surface-bounded molecular volume, and the inter-planar angle of the substituted biphenyls. In lipophilicity models of chlorinated aromatic compounds the majority of descriptors, including MTD, contain essentially the information of nCl. MTD is a good lipophilicity descriptor of chlorinated aromatic compounds either alone or in association with other descriptors. For chlorobenzenes it gives r = 0.998, s = 0.069, F = 2281, and for the set of chlorinated biphenyls r = 0.974, s = 0.255, F = 338, a better result than gives the nCl descriptor (r = 0.967). The significance of MTD descriptor in different models is discussed. Beside nCl, the MTD index encodes ortho and para effects.

MTD-PLS: a PLS-based variant of the MTD method. A 3D-QSAR analysis of receptor affinities for a series of halogenated dibenzoxin and biphenyl derivatives

MTD-PLS, the Partial Least Squares (PLS) variant of the Minimum Topological Difference (MTD) method is described. In MTD-PLS, molecules are characterised not only by the occupancy or nonoccupancy of the hypermolecular vertices (as in classical MTD), but also by additional descriptors for each vertex: fragmental van der Waals volumes, fragmental hydrophobicities, partial atomic charges, etc. This method was applied to a series of 73 polyhalogenated derivatives of dibenzo-p-dioxine, dibenzofuran and biphenyl (induction of aryl hydrocarbon hydrolase and affinities to rat cytosolic receptor), previously studied by MTD. The separation of steric, hydrophobic, and electrostatic effects was achieved retranslating from the latent variable space into a linear combination of the initial structural variables. The MTD-PLS method yields more detailed results compared to classical MTD, indicating the importance of electrostatic effects at some substituent positions.

Eosinophilic cystitis in view of two cases

Authors present their experiences with eosinophilic cystitis. In both of their cases the preoperative evaluation presumed bladder cancer, the histologic examination, however, showed eosinophilic cystitis. In this report a discussion is given on the diagnostic and treatment possibilities of the entity.

MOBISIM--package for simulation in molecular biology

A computer program for simulation of protein synthesis regulatory processes is described. A short theoretical background reveals the requirements of a simulation program. Our program, MOBISIM, offers several facilities and a user-friendly interface for molecular biologists. An example illustrates the graphical representation both as time evolution of the system or as phase diagram.

Immunologic tolerance: self-nonself discrimination versus costimulatory factors and second signals

An attempt is made to assess the total number of the theoretically possible antigenic epitopes, the number of lymphocyte clones and the number of epitopes on cell surface antibody of a clone may be able to recognize. We suggest that the structures of recognizing antibody sites of a human are far from random and derived from a limited number of structures adapted to the recognition of pathogenic agents. The probability of recognition for a random epitope-like structure is likely to be very small. Discriminative power of BCR and TCR binding sites, together with T-helper control, should be sufficient for prevention of peripheral autoimmune response, but second-signal-type controls should not be neglected as supplementary mechanisms to prevent such response.

MTD-ADJ: a multiconformational minimal topologic difference for determining bioactive conformers using adjusted biological activities

The active conformation is part of a conformational mixture with experimental activity Yexp, and is used in QSAR studies to extract more information regarding the ligand-receptor interaction. To reflect the relative amount (alpha) of the active conformation, we adjust Yexp: Yadj = Yexp - log alpha. We establish a quantitative structure-activity relationship (QSAR) between Yadj and 3D conformational characteristics for the acetylcholinesterase (AChE) hydrolysis rates of 25 acetic esters. The 3D-QSAR model was obtained using the adjusted multiconformational minimal steric/topologic difference (MTD-ADJ) method, optimizing the receptor map based on Yadj for each conformer. Yadj was updated during each step of the optimization process. alpha and Yadj are based on the Boltzmann distribution calculated using AMI (MOPAC 6.0) relative energies of the COSMIC 90 derived conformers. The MTD-ADJ results are: (i) the 3D-QSAR models obtained by this procedure have significant statistical parameters and are similar to the unadjusted (MTD-MC, using Yexp) models; (ii) the selected bioactive conformations are extended, occupy cavity vertices and, for the same structures, have the same MTD value; and (iii) the optimized conformational map of the neutral ligands obtained from the MTD-ADJ model fits well in the active site of the crystallographic structure of AChE (from Torpedo californica). We propose a neutral ligands binding site model for AChE. Our results show that MTD-ADJ, which can be implemented in any 3D-QSAR method, is capable of providing additional information regarding the active conformations, and can be used to gain further insight into the ligand-receptor models for which no structural data are available.

Quantitative structure-activity relations by the MTD-method for binding of nonapeptides to the HLA-A2.1 molecule

Binding of large series of nonapeptides to the HLA-A2.1 molecule was studied by a group of Sette in order to predict strongly binding peptides with possible therapeutic interest. Here we establish QSAR-s for these series. The MTD-method was used for steric requirements concerning amino acidic side chains as well as side chain hydrophobicities. Binding of these peptides to the HLA-A2.1 molecule is favored by a lipophylic character of side chains for the anchor position 2 and 9 and for positions 1,3 and 6 and by steric features that allow predictions for some modified amino acidic residues in these positions that should increase the peptide-HLA-molecule affinity.

Molecular aspects concerning antigen oligopeptide selection by MHC class I molecules

T cells can recognize the antigen only if it is associated with self MHC molecules on the surface of antigen presenting cells (APC). There are several characteristic parameters defining interaction of MHC molecule with antigenic peptides giving circumstances for specific antigen presentation and an individualized immune response. Here are assessed some size and conformational parameters of the peptides presented by MHC class I molecules-lengths, widths, van der Waals volumes and surfaces-using COSMIC 2.0 software. The peptides derived from HIV gp 160 are obtained from literature and are known to be active and inactive in a cytotoxicity assay. An increased tendency for beta- or beta-like structures and volumes close to those of the MHC binding site are encountered in the case of active peptides.

Continuous therapy with intravenous prostacyclin for primary pulmonary hypertension: a bridge to heart-lung transplantation

Primary pulmonary hypertension (PPH) continues to be a major problem. Vasodilator therapy has been of variable success in selected patients. Recently, with the introduction of prostacyclin (Prostaglandin I2, epoprostenon) as a potent vasodilator, several reports have shown a positive effect in primary pulmonary hypertension. We report here two patients with PPH who responded favorably to continuous intravenous therapy with prostacyclin. Both patients responded with a reduction in pulmonary vascular resistance, increase in cardiac output and dramatic improvement of right heart failure. Although therapy with prostacyclin is extremely expensive it may be used as a bridge to heart-lung transplantation in patients with end-stage PPH who do not respond adequately to alternative therapy.

Acute gastric dilatation causing respiratory failure and "tension pneumothorax" in an elderly women with a diaphragmatic hernia

The occurrence of respiratory failure as a result of a large diaphragmatic hernia is a well-described entity in infants with congenital hernias. On reviewing the literature, the authors did not find a similar clinical presentation in the adult population. They report the case of an elderly patient with a large hiatus hernia who developed recurrent episodes of life-threatening respiratory failure and hemodynamic compromise due to recurrent gastric dilatation. Decompression with nasogastric suction resulted in dramatic and immediate relief of the respiratory distress. One should keep in mind the possibility of intrathoracic gastric dilatation as a cause of acute respiratory insufficiency in patients with hiatal hernia.

Influence of drugs and ionic gradients on gastric secretory epithelium in vitro

The first part of the paper is devoted to the description of the data acquisition system for studies on epithelial membranes using a process-control computer ECAROM connected to the usual two half-chambers device for epithelial transport studies in vitro. The second part presented the results obtained in several types of experiments concerning the effect of drugs (histamine, acetazolamide) and ionic gradients (K+, Cl-, H+) on the potential difference and/or acid secretion rate.

Theoretical investigations on the role of steroid-skeleton C4 = C5 unsaturation in competitive aromatase inhibition

A quantitative structure-activity relationship (QSAR) approach by use of the minimal topological difference (MTD) method including 46 derivatives of 4-androstene-3,17-dione and 5 alpha-androstane-3,17-dione is applied to give indications about the role of the C4 = C5 double bond in competitive inhibition of human placental aromatase and about sterical requirements in steroid-aromatase interactions. The inhibitory activity is found to correlate with the sterical MTD variable, hydrophobicity, and pi-system conjugation in the A,B-ring region. A comparison of the MTD results reveals a good agreement with interpretations based on free-energy data derived from inhibition constants. By means of MM2 molecular mechanics and PCILO quantum-chemical calculations, the 4-ene structure is shown to significantly influence conformational features of C19 substituents which are important in enzymatic transformations. While 19-hydroxy-5 alpha-androstane-3,17-dione favour a conformation having the hydroxyl group in the enzyme-directed out-of-ring position, the C4 = C5 double bond energetically enables the steroid to adopt a conformation which can be hydroxylated without internal rotations. According to present theoretical findings, the 4-ene unsaturation thus exerts an indirect conformational influence by hydroxyl positioning appropriate to aromatase interactions and a direct electronic influence by pi conjugation.

MTD calculations on quantitative structure-activity relationships of steroids binding to the progesterone receptor

The minimal topological difference (MTD) method is used to describe quantitative structure-activity relationships (QSAR) for the progesterone-receptor binding affinity including 59 progestational steroids. Multiple correlation coefficients of r = 0.962 and r = 0.955 are obtained by use of the MTD variable and a measure of hydrophobicity for the series of progesterone and ethisterone derivatives, respectively. Hydrophobic effects are found to strongly influence receptor binding. In accordance with the hydrogen bonding concept, the optimized MTD receptor maps indicate cavity vertices in the regions of oxygen functions at C3 and in the 17 beta position. Receptor wall vertices are attributed in the areas of 4, 10 beta, and 13 beta substituents of 4-en-3-one steroids while 17 alpha side chains additionally contain receptor cavity vertices. A comparison of corresponding receptor maps suggests in accord with X-ray crystal structure data that progesterone and ethisterone derivatives are bound in somewhat different orientations relative to the receptor surface.

HLA antigens, jejunal morphology and associated diseases in children with dermatitis herpetiformis

Forty-five Hungarian and Finnish children from 1.5 to 15 years with dermatitis herpetiformis were studied for HLA antigens, jejunal morphology on gluten-containing diet and associated diseases in the patients and their relatives. A strong association with HLA-B8 was found in patients of both nationalities, the relative risks were 12.8 and 9.6, respectively. The Hungarian patients were also typed for HLA-DR locus, and an association with DR3 but not with DR7 was observed. Patients with subtotal villous atrophy had slightly more often HLA-B8 and DR3 than those with milder intestinal lesions. Atopic eczema occurred in 20% of the patients and family history of atopy seemed to have an inverse correlation with HLA-B8 and DR3.

Electrical stimulation of the bladder and gravidity

Following experimental investigations, the authors have performed bladder stimulator implantation for paralyzed bladder patients since 1969. Up to 1983 altogether 32 operations were carried out for bladder paralysis following 21 peripheral and 11 central neural lesions. The patients urinated without residue after the operation. The observations showed that regular use of the stimulator led to the elimination of reflux in patients who had vesicoureteral reflux before the operation. It was found that, if the stimulator had to be removed for any reason after a period of 1 or 2 years, the urinating ability was maintained. Of the 7 female patients operated, 2 became pregnant. During pregnancy and delivery, the patients did not experience any problem with the implanted stimulator, and the children were born healthy and at term.

MTD approach to quantitative structure-activity relationships for cardiotonic steroids

A minimal topological difference (MTD) approach is made to describe quantitative structure-activity relationships (QSAR) for the Na+, K+-ATPase inhibitory activity of cardiotonic steroids. The calculations take into account 20 derivatives of digitoxigenin, digoxigenin, and gitoxigenin with small substituents at different sites of the steroid backbone. A multiple correlation coefficient of r = 0.916 is obtained using the MTD and an indicator variable for the presence of a 15 beta substituent. The corresponding receptor map reveals receptor wall vertices in the C11, C12, C15, and C22 regions. Both 3 beta and 16 beta substituents are found to contain receptor cavity vertices. The MTD results are discussed with respect to lactone-ring conformational investigations presented and they are compared with findings of previous structure-activity studies.

QSAR application in chemical carcinogenesis. II. QSAR analysis of a class of carcinogenesis inhibitor: retinoids

Quantitative structure-activity relationships for the reversion of keratinization of hamster tracheal cell organ culture by structurally related retinoids were formulated. Their biological activities (ED50 . M) were correlated with the following parameters: the minimal topological difference (describing the fit of the considered molecules with a possible receptor site) and the lipophilicity constants. For computation purposes the retinoids were divided in three series (A, B and C) according to structural modifications in the cyclic moiety of the molecule, in the polienic chain and in the terminal functional group, respectively. The computed regression equations suggested the importance of the stereochemical features of cyclic moiety (for series A, eq. 1, n = 19, r = 0.926, F = 48.19) and of the uninterrupted conjugation for the polienic chain (for series B, eq. 6, n = 11, r = 0.954, F = 39.39) for the biological activity. In order to check the prediction potential of the regression equation computed for the overall set of compounds (eq. 10, n = 53, r = 0.853, F = 32.11), it was used to calculate the ED50 for a test series of 15 retinoids. The correlation obtained between ED50 exp and ED50 calc for this series was r = 0.916, F = 60.25. The nature of the receptor site possibly involved in the interaction with retinoids was discussed.

[Recurrence prevention of papillomas of the bladder using lycurim instillation]

Following surgical removal of papillary tumours of the bladder from 60 patients the authors performed short instillations of the bladder with LYCURIM. The histological picture revealed tumours in the stage O-A-B1 and grade I-II-III. In a control group (n = 129) 89 recidive cases were observed in 2 years. Out of the 60 patients of the LYCURIM group 19 (31.7%) were free of tumours for 2 years and 43 (71.7%) for 11/2 years. A transient cystitis which occurred with short application of the medicament was easily cured. Toxic effects on the blood picture were not observed.

[Importance of a persisting left vena cava superior in pacemaker therapy (author's transl)]

Basing on the description of a specific case and a review of literature, the article discusses the relationship between persisting left ven cava superior and pacemaker therapy. The article covers the technical problems caused by the vascular anomaly, the complications which can be expected, the possibilities in respect of recognising the vascular anomaly, as well as the methods for coping with the special situation prevailing in a particular case.

[Analysis of histochemical changes caused by acute Wofatox poisoning in a model experiment]

Effect of Wofatox on the central nervous system, striated muscles and on the myocardium of rats has been studied by the aid of light- and electron microscopic histochemistry. A single intraperitoneal injection of LD50 of Wofatox resulted in a total inhibition of the activity of histochemically demonstrable acetyl-cholinesterase in the central nervous system. Each striated muscle fiber has shown different sensitivity to the inhibitor, but enzyme activity of end motor plates could not be totally inhibited. In lethal acute intoxication ultrastructural changes of the myocardiuim have shown characteristic features of cardiomyopathy.

Quantitative structure-activity relationships in erythromycin group with MTD technique

Quantitative structure-activity correlation studies were performed for a group of 17 erythromycin derivatives modified in the C-8--C-12 portion of the molecule. The minimal steric difference, MTD, was used as the structural parameter and logarithm of the biological potency measured by a standard assay, as the biological parameter. The influence of the sp2 hybridization at C-9 and of the presence of 11, 12-carbonate grouping on the antibacterial activity was shown. The reported results give a further support to our hypothesis on greater complementarity of the cyclic 11, 12-carbonates in the reaction on the bacterial ribosomes in comparison with their parent antibiotics.

[Radiographic changes following transurethral cryocaustic surgery of the prostate gland (author's transl)]

Presentation of the cryocaustic procedure and its radiographic features on the postoperative urethrogram. For correct interpretation, a preoperative study is important.

Minimal steric difference study of structural requirements for the luteinizing hormone-releasing hormone (LH-RH) receptor

Quantitative structure-activity relation for amino acid substitution analogues of the LH-RH decapeptide were established by means of the receptor site mapping procedure based upon minimal steric differences. For a series of 17 analogues of LH-RH, obtained by substitutions of the C-terminal Gly-NH2 residue, a corelation coefficient r = 0.93 was obtained, for a series of 7 analogues, obtained by substitutions of the Leu7 residue, r = 0.95 was obtained. The shape of the LH-RH receptor regions interacting with the C-terminal of the decapetide and with the Leu7-side chain is inferred from this study.