[Update on collaborative autopsy-based research in German pathology, neuropathology, and forensic medicine]

BACKGROUND

Autopsies are a valuable tool for understanding disease, including COVID-19.

MATERIALS AND METHODS

The German Registry of COVID-19 Autopsies (DeRegCOVID), established in April 2020, serves as the electronic backbone of the National Autopsy Network (NATON), launched in early 2022 following DEFEAT PANDEMIcs.

RESULTS

The NATON consortium's interconnected, collaborative autopsy research is enabled by an unprecedented collaboration of 138 individuals at more than 35 German university and non-university autopsy centers through which pathology, neuropathology, and forensic medicine autopsy data including data on biomaterials are collected in DeRegCOVID and tissue-based research and methods development are conducted. More than 145 publications have now emerged from participating autopsy centers, highlighting various basic science and clinical aspects of COVID-19, such as thromboembolic events, organ tropism, SARS-CoV‑2 detection methods, and infectivity of SARS-CoV-2 at autopsy.

CONCLUSIONS

Participating centers have demonstrated the high value of autopsy and autopsy-derived data and biomaterials to modern medicine. The planned long-term continuation and further development of the registry and network, as well as the open and participatory design, will allow the involvement of all interested partners.

Beta-amyloid pathology in the entorhinal cortex of rats induces memory deficits: implications for Alzheimer's disease

Alzheimer's disease is characterized by the presence of senile plaques in the brain, composed mainly of aggregated amyloid-beta peptide (Abeta), which plays a central role in the pathogenesis of Alzheimer's disease and is a potential target for therapeutic intervention. Amyloid plaques occur in an increasing number of brain structures during the progression of the disease, with a heavy load in regions of the temporal cortex in the early phases. Here, we investigated the cognitive deficits specifically associated with amyloid pathology in the entorhinal cortex. The amyloid peptide Abeta(1-42) was injected bilaterally into the entorhinal cortex of rats and behavioral performance was assessed between 10 and 17 days after injection. We found that parameters of motor behavior in an open-field as well as spatial working memory tested in an alternation task were normal. In contrast, compared with naive rats or control rats injected with saline, rats injected with Abeta(1-42) showed impaired recognition memory in an object recognition task and delayed acquisition in a spatial reference memory task in a water-maze, despite improved performance with training in this task and normal spatial memory in a probe test given 24 h after training. This profile of behavioral deficits after injection of Abeta(1-42) into the entorhinal cortex was similar to that observed in another group of rats injected with the excitotoxic drug, N-methyl-d-aspartate. Immunohistochemical analysis after behavioral testing revealed that Abeta(1-42) injection induced a reactive astroglial response and plaque-like deposits in the entorhinal cortex. These results show that experimentally-induced amyloid pathology in the entorhinal cortex induces selective cognitive deficits, resembling those observed in early phases of Alzheimer's disease. Therefore, injection of protofibrillar-fibrillar Abeta(1-42) into the entorhinal cortex constitutes a promising animal model for investigating selective aspects of Alzheimer's disease and for screening drug candidates designed against Abeta pathology.

Diagnostic significance of HLA-DQ typing in patients with previous coeliac disease diagnosis based on histology alone

BACKGROUND

Coeliac disease is strongly associated with human leukocyte antigen (HLA)-DQ2 or DQ8 genotypes. The diagnosis is based on demonstrating crypt-hyperplastic villous atrophy, endomysial or transglutaminase antibodies and correlation of disease activity with gluten intake.

AIM

To evaluate the clinical utility of HLA-DQ typing, when coeliac disease diagnosis had previously been established solely by histology.

METHODS

HLA-DQ alleles, endomysial and transglutaminase antibodies were investigated and histology slides reviewed in 70 patients diagnosed 2-25 years earlier by small-intestinal biopsy but without measuring endomysial or transglutaminase antibodies. Patients without DQ2 or DQ8 or without unequivocal villous atrophy were followed-up on free diet by using serology and biopsies.

RESULTS

All 40 endomysial/transglutaminase antibodies positive patients carried DQ2 or DQ8, and 39 of them had severe villous atrophy. Only 56% of patients without endomysial or transglutaminase antibodies positivity had DQ2 or DQ8 (P < 0.001). Seropositivity and relapse developed in 4 of 11 DQ2 positive but in none of 15 DQ2 and DQ8 negative patients on long-term gluten exposure.

CONCLUSIONS

Coeliac disease diagnosis based solely on histology is not always reliable. HLA-DQ typing is important in identifying DQ2 and DQ8 negative subjects who need revision of their diagnosis, but it does not have additive diagnostic value if endomysial positivity is already known.

Implantable biodegradable polymers for IUdR radiosensitization of experimental human malignant glioma

PURPOSE

The potential of halogenated pyrimidines for the radiosensitization of human malignant gliomas remains unrealized. To assess the role of local delivery for radiosensitization, we tested a synthetic, implantable biodegradable polymer for the controlled release of 5-iodo-2'-deoxyuridine (IUdR) both in vitro and in vivo and the resultant radiosensitization of human malignant glioma xenografts in vivo.

MATERIALS AND METHODS

In vitro: To measure release, increasing (10%, 30%, 50%) proportions (weight/weight) of IUdR in the polyanhydride [(poly(bis(p-carboxyphenoxy)-propane) (PCPP): sebacic acid (SA) (PCPP : SA ratio 20:80)] polymer discs were incubated (1 ml phosphate-buffered saline, 37 degrees C). The supernatant fractions were serially assayed using high performance liquid chromatography. To measure modulation of release, polymer discs were co-loaded with 20 microCi 5-125-iodo-2'-deoxyuridine (125-IUdR) and increasing (10%, 30%, or 50%) proportions of D-glucose. To test radiosensitization, cells (U251 human malignant glioma) were sequentially exposed to increasing (0 or 10 microM) concentrations of IUdR and increasing (0, 2.5, 5.0, or 10 Gy) doses of acute radiation. In vivo. To measure release, PCPP : SA polymer discs having 200 microCi 125-IUdR were surgically placed in U251 xenografts (0.1-0.2 cc) growing in the flanks of nude mice. The flanks were reproducibly positioned over a collimated scintillation detector and counted. To measure radiosensitization, PCPP : SA polymer discs having 0% (empty) or 50% IUdR were placed in the tumor or contralateral flank. After five days, the tumors were acutely irradiated (500 cGy x 2 daily fractions).

RESULTS

In vitro: Intact IUdR was released from the PCPP : SA polymer discs in proportion to the percentage loading. After 4 days the cumulative percentages of loaded IUdR that were released were 43.7 +/- 0.1, 70.0 +/- 0.2, and 90.2 +/- 0.2 (p < 0.001 ANOVA) for the 10, 30, and 50% loadings. With 0, 10, 30, or 50% D-glucose co-loading, the cumulative release of 125-IUdR from PCPP : SA polymers was 21, 70, 92, or 97% (p < 0.001), respectively, measured 26 days after incubation. IUdR radiosensitized U251 cells in vitro. Cell survival (log10) was -2.02 +/- 0.02 and -3.68 +/- 0.11 (p < 0.001) after the 10 Gy treatment and no (control) or 10 microM IUdR exposures, respectively. In vivo: 125-IUdR Release: The average counts (log10 cpm +/- SEM) (hours after implant) were 5.2 +/- 0.05 (0.5), 4.3 +/- 0.07 (17), 3.9 +/- 0.08 (64), and 2.8 +/- 0.06 (284). Radiosensitization: After intratumoral implantation of empty polymer or intratumoral 50% IUdR polymer, or implantation of 50% IUdR polymers contralateral to tumors the average growth delays of tumors to 4 times the initial volumes were 15.4 +/- 1.8, 20.1 + 0.1, and 20.3 + 3.6 (mean + SEM) days, respectively (p = 0.488 one-way ANOVA). After empty polymer and radiation treatments, no tumors regressed and the growth delay was 31.1 + 2.1 (p = 0.046 vs. empty polymer alone) days. After implantation of 50% IUdR polymers either contralateral to the tumors or inside the tumors, followed by radiation, tumors regressed; growth delays to return to the initial average volumes of 14.0 + 3.6 or 24.2 + 0.2 (p < 0.01) days, respectively.

CONCLUSIONS

Synthetic, implantable biodegradable polymers hold promise for the controlled release and local delivery of IUdR for radiosensitization of gliomas.

[Sinoatrial block caused by gastroesophageal reflux. The role of simultaneous 24 hr. esophageal pH-metry and Holter-ECG in the differential diagnosis of angina pectoris]

The authors report on a 61-year-old female patient, who has suffered from recurrent angina-like chest pain for 30 years. The patient's complaints became intolerable, in spite of therapy with nitroglycerin, H2 receptor blockers and sedative medication. The echocardiography, the ECG exercise testing and Thallium scintigraphy were normal, the upper gastrointestinal endoscopy did not prove oesophagitis either macroscopically or microscopically. The simultaneous 24-hr Holter ECG monitoring and esophageal pH-metry demonstrated pathological acid gastro-oesophageal reflux and frequent sinoatrial blocks (Mobitz I) in painful periods. After monotherapy with proton pump inhibitor (omeprazole) the patient became complaint-free. Repeated combined 24-hr oesophageal pH-metry and Holter ECG monitoring indicated nonpathological acid reflux and insignificant number of sinoatrial blocks. During the course of 19 months the patient was asymptomatic. The acid pump inhibitor was stopped for a 10 day-period, while the chest pain returned. The combined 24-hr Holter ECG and esophageal pH-metry proved pathological acid gastro-oesophageal reflux and frequent sinoatrial blocks during chest pain period. After treatment with acid pump inhibitor the patient became asymptomatic again.

CONCLUSIONS

1. The acid gastro-oesophageal reflux may be a provocative factor of sinoatrial blocks and it can be influenced by proton pump inhibitor successfully. 2. Simultaneous 24-hr oesophageal pH-metry and Holter ECG monitoring can be contribute to the differentiation among causes of atypical chest pain.

[Adverse effects of combined use of acenocoumarol and acetylsalicylic acid after myocardial infarct and unstable angina]

The authors examined the bleeding complications in 75 patients who received acenocoumarol and acetylsalicylic acid combined therapy. The studied population suffered from either acute myocardial infarction or unstable angina. Among the 75 patients in two cases (2.7%) appeared serious bleeding and in another 25 cases (33.3%) mild bleeding complications. There were no fatal cases. Comparing these data with literary data, the authors stated that in the study group the proportion of serious complications didn't increase in comparison with patients who received either acenocoumarol, warfarin or acetylsalicylic acid but mild bleeding appeared more frequently. This finding suggests that in high risk patients the combined acenocoumarol-acetylsalicylic acid therapy can be considered under strict control.

The main elements of the information system of the National Stroke Program (Smart Card - Telecommunication - Knowledge Bases)

The mortality of stroke in Hungary is 208 out of 100,000 inhabitants, which is very high in an international comparison. The age-group most in danger is between 35 and 50. There are 40-50 thousand hospital admissions each year because of stroke, the majority of them are unexpected crisis cases. In 1992, the government announced the National Stroke Program, which includes prevention, emergency, acute treatment and rehabilitation. Simultaneously with the medical-professional program, the National Stroke Program Information System (NSPI) has also been launched. Its aim is the direct backing up of the medical activity, the aiding of epidemiological tasks and preventive follow-up of patients. The system consists of an interactive database network in that it can guarantee accessibility, thus making every endeavour to assist in solving medical-professional problems with the help of modern information technology (smart care, telecommunication-device, etc.).

Lipid solubility of pancuronium and vecuronium determined by n-octanol/water partitioning

We have measured the n-octanol/water distribution coefficients at 37 degrees C of two steroidal myoneural blockers (pancuronium and vecuronium) and of their 3-hydroxy metabolites over a pH range from 1.5 to 11. Pancuronium was found not to be lipid soluble. The mean distribution coefficient of 3-hydroxy vecuronium at pH = 7.4 was 0 and that of vecuronium 0.12 (SD 0.1). Distribution coefficients of the parent drug showed a slightly greater lipid solubility than the metabolite (11.37 (2.91) and 9.53 (3.44), respectively (mean t0.05 x SE)). Because of its lipid solubility, vecuronium may penetrate into lipid structures.

Intramedullary spinal sarcoidosis: clinical and magnetic resonance imaging characteristics

We present a retrospective series of the clinical and MRI findings in 16 patients with intramedullary spinal sarcoidosis (ISS), including 12 patients studied with gadolinium-DTPA. The spectrum of MRI findings includes leptomeningeal enhancement, fusiform spinal cord enlargement, focal or diffuse intramedullary disease, and spinal cord atrophy. We present a classification of ISS correlating the clinical progression and the temporal sequence of MRI abnormalities. Improvement occurred in five of 12 patients (42%) treated with immunosuppressive therapy.

[A case of serum cholinesterase anenzymia]

A report is given on a 66-year-old man suffering from serum cholinesterase anenzymia. The following tests were performed to characterize the genetic pseudo-cholinesterase variants: plasma cholinesterase activity using benzoyldicholine as substrate (according to Kalow) and dibucaine and sodium fluoride as inhibiting substances. In addition, polyacrylamide density gradient gel electrophoresis followed by esterase staining technique (Mascall) was used for the electrophoretic separation of cholinesterase isoenzymes. Similarly, the only daughter's and the granddaughter's sera were analyzed. Determination of activity and inhibitor numbers indicated that the propositus had the homozygote "silent gene" genotype (A = 2, DN = 0, FN = 0). The granddaughter showed an isoenzyme constellation within normal ranges (A = 128, DN = 80, FN = 58); for the daughter apparently normal values were also found for activity and inhibitor numbers (A = 73, DN = 82, FN = 58). Figure 1 shows the results of electrophoretic separation from the sera tested and Fig. 2 results obtained by densitometric assessment. Electrophoretic separation and the zymogram obtained from the propositus' serum show only sample peak and albumin fractions. In contrast, the granddaughter's serum turned out to be absolutely normal. In the daughter's sample, however, three cholinesterase components normally found in serum were missing, as also shown by densitometry. Despite apparently normal activity and rather insignificant inhibitor numbers, gradient gel electrophoresis clearly revealed her to be a heterozygote carrier of the silent gene Es variant. As our data are in accordance with results obtained by other investigators, this observation cannot be regarded as exceptional.(ABSTRACT TRUNCATED AT 250 WORDS)

[Gallbladder torsion in infants]

The infrequent case of gallbladder torsion and accompanying Meckel's diverticulum in a 3-year-old girl, is described. Detorquation, cholecystectomy and resection of the diverticulum were performed. Condition of the development of the disease as well as its clinical aspects and therapy are discussed. It is suggested to explore the abdominal cavity for other developmental anomalies in the course of the operation. The patient recovered without complications and left the hospital 14 days after the operation.

Identification of mononuclear cells in CSF of patients with HIV infection

Using immunocytochemical methods, CSF lymphocyte subpopulations were examined in different neurologic disorders associated with human immunodeficiency virus (HIV) infection. CSF pleocytosis was observed in asymptomatic neurologically normal subjects, in patients with aseptic meningitis, and those with inflammatory demyelinating neuropathies, but infrequently in subjects with AIDS dementia complex. The distribution of CSF lymphocyte subpopulations in HIV-infected patients differed from control subjects showing decreases in percentages of T helper (CD4) cells and increases in T suppressor (CD8) cells. Peripheral blood and CSF CD4:CD8 ratios were inverted in all of the neurologic disorders studied. In all disorders, the changes in CSF composition of mononuclear cells paralleled alterations in peripheral blood and in patients with AIDS dementia complex, there was a relationship between the severity of dementia and blood and CSF CD4 lymphocyte proportions.

[Two new oncometers--results of a comparative study]

In the course of a series of measurements of colloid oncotic pressure two newly introduced instruments were compared with an approved standard COD-measuring device as to accuracy and operational comfort. While the comparative tests produced practically identical results one instrument (number 2; Osmomat 050) did stand out for high precision but concerning speed of adjustment and simplicity in handling it was somewhat inferior to number 1 (BMT 921). The importance of repeated (or quasi on line) clinical control of colloid osmotic pressure by the aid of newly developed instruments now rather easy to operate is briefly outlined.

Cell proliferation in response to vitreous hemoglobin

Rabbits were examined at intervals to 90 days after receiving two or three intravitreal injections, on consecutive days, of homologous hemoglobin or saline. Cell proliferation in the vitreous was assessed by scintillation counting and radioautography after intravitreal administration of 3H-thymidine 4 hr prior to sacrifice. Two populations of vitreous cells phagocytize the vitreous hemoglobin and are stimulated to DNA synthesis. Cells that migrate into the vitreous in response to hemoglobin also contribute to total 3H-thymidine uptake. Tritiated thymidine incorporation peaks between 5 to 10 days and again between 22 to 30 days after the first administration of hemoglobin. By 45 to 60 days after two injections and 90 days after three injections the vitreous cell proliferative activity has returned to normal. It is concluded that a bleeding event which leads to the release of hemoglobin in the vitreous stimulates a minor, transient vitreous cell proliferation and a more significant, but also transient, migration of cells into the vitreous. Aside from contributing by phagocytosis to vitreal clearing, no other functions have been ascribed to these cells.