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We present a new method for model-based mutation-driven test case generation. Mutants are generated by making small syntactical modifications to the model or source code of the system under test. A test case kills a mutant if the behavior of the mutant deviates from the original system when running the test. In this work, we use hyperproperties-which allow to express relations between multiple executions-to formalize different notions of killing for both deterministic as well as non-deterministic models. The resulting hyperproperties are universal in the sense that they apply to arbitrary reactive models and mutants. Moreover, an off-the-shelf model checking tool for hyperproperties can be used to generate test cases. Furthermore, we propose solutions to overcome the limitations of current model checking tools via a model transformation and a bounded SMT encoding. We evaluate our approach on a number of models expressed in two different modeling languages by generating tests using a state-of-the-art mutation testing tool., (© The Author(s) 2021.)

A boy, 2 years old, developed a HUS after a pneumonitis. He was treated with Heparin, salicylates and recurrent peritoneal dialysis and recovered slowly. The course of the disease was complicated by myocarditis, gastric hemorrhage and severe neurologic disturbances. 7 days after unset of hemolysis a cold agglutinin titer of 1:256 was detected. This fact arises the question whether infection with Mycoplasma pneumoniae and the presence of cold agglutinins in serum could be involved in the development of HUS. The possibility of a viral etiology for this disease is discussed.

Meteorism is a nonspecific symptom and it is difficult to exclude organic causes. In one of our patients, a 6 years old girl, the accumulation of gas had caused changes of the normal abdominal situs. Finally psychogenic aerophagia could be detected by exact analysis of the case history and the daily rhythm of meteorism. The situation within the family could be revealed as trigger mechanism and there an successful therapy was started.

40 children with clinical diagnosis of bronchial asthma aged 8--14 years, 39 with allergic disposition, were investigated. Acute therapeutic and protective effect on frequency of asthmatic attacks, pulmonary auscultation and lung function (FEV1, PF, FVC) by application of Fenoterol and Ipratropium as combination aerosol were registered. Over a period of 4 weeks we could reduce the frequency of attacks nearly to the half. 10 and 20 minutes after aerosol application we showed a good improvement of pulmonary ventilation. Only on children with severe asthma bronchiale an exclusive treatment with Berodual seems to be of modest protective effect.

Long term hemodialysis and kidney transplantation has proved to be a very efficient method in the treatment of renal failure in childhood. Accordingly, the number of children treated by dialysis and transplantation in Europe is still increasing. At this time more than 1250 have been treated. As a result of recent studies, one to two children under the age of 15 years per one million population per one year reach the terminal stage of renal insufficiency. We performed our own informative study in 1975 to estimate the needs for dialysis facilities in Austria. Our results are in line with those of other projects. In view of the special childhood problems (growth, puberty, psychological problems, schooling etc.) there is a need for specialized pediatric centers which should include the facilities for nephrologic out- and in-patient treatment, a dialysis team consisting of a pediatrician, pediatric nurses, teacher, child psychologist, dietician and social worker. These enormous investments in apparature, personnel and organization are justified by the good results of survival and the reasonably normal life these children can lead.

The rare X-ray finding of urinary bladder wall calcifications in a newborn is reported. The newborn suffered from micturition disturbance caused by urethral valves, bilateral hydroureter and bilateral hydronephrosis. No possible definite cause for the calcification of the bladder wall could be found. The calcifications could never be detected by X-ray after the age of 5 months.

Two boys with presumably congenital cystic changes in the lungs are described. In one child multiple cystic deformations led to acute symptoms of severe respiratory distress necessitating urgent resection of the right middle and upper lobes. The other boy had a large thick-walled cyst in the left upper lobe causing no distress whatsoever. This patient was observed for more than 6 years before operation. Multiple vascular anomalies and anastomoses were revealed during surgery. Both cases are presented in detail and the completely different clinical course is outlined. Only when careful supervision of intrapulmonary cystic changes is guaranteed can operation be postponed for longer than 6 months. Pulmonary cysts may lead to emergency procedures. They are always a potential source of serious complications such as rupture or infection. When no tendency for regression can be discovered surgical removal is indicated. Conservative treatment will not influence the course. Differential diagnosis is discussed briefly.

One particular form of an anorectal malformation--the anterior perineal anus--is frequently overlooked in the neonate period because defecation is easy at this age. However, with the change of diet, this malformation as a rule leads to chronic constipation. The lateral view at the beginning of an irrigoscopy usually shows a characteristic picture of a horizontal caudal limitation of the rectum, a dorsal pouch, a beakshaped fistula and an elevation of the anorectal transition. These findings contribute essentially to the clinical diagnosis and permit early operation.

Alport's syndrome is a hereditary nephropathy with grave prognostic consequences. The occurrence of this disease is probably more frequent than was assumed until now - many cases are not immediately recognized as such. It is possible to make a clinical diagnosis from detailed family histories and through careful examinations of family members including audiometric tests. In the early stages of the disease children merely have recurrent macro- or microhematuria. Renal functional tests are normal and there is general well-being of the patient. Whereas the biopsy specimens examined by light microscopy show non-specific alterations, those examined under the electronmicroscope already show specific defects of the basement membrane. Our studies lead us to believe that these morphologic findings correspond with changes of the basement membrane, detectable by immunochemical investigations. 6 of 12 patients have been biopsied in recent time and the above cited typical changes of the basement membrane could be demonstrated. Therefore these investigations are recommended in Alport's syndrome.

During the past 2 years 7 children received kidneys from cadaveric donors. 2 transplants had to be removed because of irreversible chronic rejection and 1 recipient died on the 4th day after surgery. The remaining 4 recipients are doing well. In the evaluation of the results special emphasis is placed on the normalization of growth and puberty. The difficulties of psychosocial rehabilitation are stressed.

Potter-syndrome with agenesia of the kidneys and typical face is only one variation of the big group of renofacial dysplasia. Among our patients which are under treatment because of malformations of the urinary tract very often we see children with dysplastic faces or malformed ears. Therefore vice versa patients with alterations of ears and face should be exactly investigated to exclude urinary tract malformations.

Alpha-1-antitrypsin was determined in children with glomerular diseases by means of a quantitative radial immunodiffusion method. The concentration of this inhibiting protein has been found to be very low during relapses. An attempt has been made to correlate this finding with the clinical picture and the presumed underlying pathological mechanism. The loss of this inhibitor due to proteinuria is one of the explanations, in concurrence with the findings of other authors. The second explanation lies in the consumption of the inhibitor protein as a consequence of the reaction with liberated proteolytic enzymes.

The serum and urine levels of alpha-2-macroglobulin (alpha2-MG) was determined in 33 children with glomerular diseases and in 26 healthy control children. Healthy children showed a minimum level of 275 mg% and maximum level of 337 mg%, with a mean concentration of 301 mg% and a standard deviation of 13 mg%. No alpha2-MG was detected in the urine. Steroid-treated patients with idiopathic nephrotic syndrome displayed elevated inhibitor levels of up to 490 mg%. This might be a direct result of steroid therapy or a consequence of reactively-increased protein synthesis in response to the renal protein loss. In all these patients the urine was found to be alpha2-MG-negative, irrespective of the presence or absence of proteinuria. In the miscellaneous group of glomerulopathies without the nephrotic syndrome, serum levels of alpha2-MG were shown to be normal. The urinary concentrations of alpha2-MG were related to the activity of the disease. alpha2-MG determination in serum and urine seems to be a tool for differential diagnosis and prognosis in some cases of glomerular disease.

The prolonged use of a salt restricted infant formula (1.9 mEq Na/kg/day and 1,4 mEq C1/kg/day) in a child with undiagnosed cystic fibrosis led to a life threatening metabolic disturbance. The main features were hypochloraemic alkalosis due to massive loss of electrolytes in the sweat. Urinary electrolyte excretion, however, had been lowered to a minimum due to aldosteron induced reabsorption. Plasma aldosterone levels were initially high, but returned to normal after addition of salt to the feeds. Prior to admission a sweat test had been negative. The patient clearly demonstrates the unique metabolic feature of cystic fibrosis of the ability to retain electrolytes in the tubulus and at the same time the inability of the sweat glands to reabsorb sodium and chloride. Contrary to present experience severe prolonged salt restriction is believed to be able to diminish sweat electrolytes to subpathological values.