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S Pollak

Publications and source records attributed to S Pollak.

At least 37 records · Page 2Linked to original sources
PubMed1990

High resolution high performance liquid chromatography fingerprinting of purified human chorionic gonadotropin demonstrates that oxidation is a cause of hormone heterogeneity.

To characterize the structures of the various forms of hCG and its immunologically related fragments measured in blood, urine, and tissue culture media, we developed a highly sensitive HPLC tryptic fingerprinting system that can characterize as little as 15 micrograms of material. Standard preparations of the subunits of hCG purified from pregnancy urine were found to exhibit heterogeneity on reverse phase HPLC chromatography, complicating efforts to characterize such forms of hCG. The same type of chromatographic heterogeneity was observed when the hormone was reduced and S-carboxymethylated (RCM) and its RCM subunits separated on HPLC. One major and one minor peak were observed in the alpha- and beta-subunits from both native and RCM hormone, with a ratio of between 5:1 and 10:1. Development and application of a high resolution, semimicrobore HPLC fingerprint technique used together with an examination of selected peptides by amino acid sequencing and mass spectrometry defined the differences between these forms as oxidation. Using each of the isolated RCM subunit's major and minor HPLC peaks, the oxidation was shown to be reversible and probably due to interconversion of methionine with its sulfoxide form.

Chorionic Gonadotropin↗
PubMed1990

[Injury patterns and roentgen findings in gunshot wounds with rare flint ammunition].

Smoothbore shotgun barrels can fire cartridges with common pellet loads as well as shotgun slugs and rubber bullets. Other than conventional shot, the cylindrical Brenneke-type rifled shotgun slugs sometimes cause perforating wounds. The shotgun ammunition for use in self-defence can have a single projectile or several rubber pellets. Where the propellant is black powder, short range shots will probably leave searing marks and intensive soot deposits. Fired at close range, rubber bullets can penetrate through the skin into the body, fired at greater distance they cause contusions. A case of homicide (repeated firing with a 12-ga. pump gun) is used to present and discuss the injury patterns and X-ray findings after impact of Brenneke-type slugs and rubber bullets as well as of "classical" shot pellets.

Firearms↗
PubMed1989

Crystallization and characterization of human chorionic gonadotropin in chemically deglycosylated and enzymatically desialylated states.

Crystals suitable for X-ray diffraction studies at moderate resolution have been grown from two forms of human chorionic gonadotropin (hCG): HF-treated hCG and neuraminidase-treated hCG. The enzymatically desialylated form of hCG produced crystals that diffract to 2.8 A as compared to the HF-treated hCG crystals that diffract to 3.0 A. Although it was assumed that the high and heterogeneous carbohydrate content of the glycoprotein hormones inhibited their crystallization, this report suggests that it is the negatively charged surface sugars and neither the total carbohydrate content nor its heterogeneity which interferes with crystal formation. Chemical deglycosylation resulted in significantly increased protein degradation during crystal growth. Such peptide bond cleavages were observed to a much lesser extent in the crystals grown from neuraminidase-digested hCG. Sequence analysis of the HF-treated hCG crystals suggested that up to 45% of the molecules within the crystal had an acid-labile peptide bond cleaved. In contrast, the neuraminidase-treated hCG exhibited less than 9% of this type of cleavage. The increase in heterogeneity of the polypeptide chains within both crystals over that existent in the starting proteins was apparently due to changes occurring during crystal growth. The manner in which hCG was treated prior to crystallization was found to be a very important factor in the extent of peptide bond cleavages occurring during crystal growth. HF treatment of glycoproteins may render glycoproteins more susceptible to peptide bond cleavages during crystal growth.

Amino Acid Sequence↗
PubMed1989

[The high autopsy rate in Vienna].

In 1983 34% of all persons who died in the Republic of Austria were autopsied. We examined the frequency of postmortem examinations in the capital city, Vienna, between 1983 and 1987 in view of this high overall autopsy rate. The annual autopsy rate in all 9 pathology institutes and the department of legal medicine of the University of Vienna was on average 51 to 53%. There was a slight statistically verifiable decline in 1987. The reason for this high necropsy rate is that Austrian law permits the autopsies without the consent of next of kin if it appears indicated for medical, scientific or educational reasons; further more the fact, that the chairman of the department is at the same time the coroner for the hospital. A high autopsy rate is necessary to maintain a high standard of diagnostic accuracy even in modern medicine. The diagnoses were inaccurate or incomplete in 15% of all cases. The high autopsy rate is the basis for extremely accurate mortality and morbidity statistics and provides the basis for long range public health planning. Medical students develop an insight in disease patterns, which cannot be gained in any other way. The pathology departments of Vienna introduce a new city-wide computer-supported diagnostic file system, which will provide a baseline for comparative scientific studies.

Austria↗
PubMed1989

Typhoid fever diagnosed by isolation of S. typhi from gastric aspirate.

The diagnosis of typhoid fever (TF) is usually established by culturing S. typhi from the blood or by serology. In this report we describe three patients in whom the diagnosis of TF was made by the isolation of S. typhi from gastric contents, despite negative blood urine and stool cultures. Culture of gastric contents has not previously been recognized as a diagnostic tool in this disease.

Child↗
PubMed1989

Defective leukocyte fungicidal activity in end-organ resistance to 1,25-dihydroxyvitamin D.

Recent studies have shown 1,25(OH)2D3 receptor-mediated modulation of leukocyte proliferation, differentiation, and function. We examined the phagocytosis and killing of microorganisms by neutrophils and monocytes from five patients of three families with hereditary resistance to 1,25(OH)2D3. Phagocytosis of microorganisms by patients' neutrophils and monocytes was normal. However, defective neutrophil killing activity toward Candida albicans (30-40% of controls) was found in all patients. The killing of Staphylococcus aureus was normal. The neutrophil chemiluminescence, nitroblue tetrazolium (NBT) dye reduction, and the generation of superoxide ions and hydrogen peroxide by neutrophils and monocytes after induction by either soluble stimuli or zymozan particles, did not differ from those in controls. The neutrophil myeloperoxidase activity was also normal. Monocytes obtained from two patients of different families before long-term calcium infusion therapy and after they became normocalcemic, demonstrated a similar impaired fungicidal activity toward Saccharomyces cerevisiae, indicating that hypocalcemia itself was not the cause of the killing defect. However, the addition of the Ca+2 ionophore A23187 (1 microM) to the test medium restored the monocyte fungicidal activity to normal. As patients' neutrophil cytosolic free calcium concentration was similar to that in controls, it is suggested that 1,25-(OH)2D3 exerts its effect on leukocyte function by a putative receptor-mediated regulation of subcellular calcium localization which may be important for fungicidal activity.

Calcitriol↗
PubMed1989

[Simulation of strangulation findings by postmortem rescue and transport measures].

Improper rescue or transportation of a corpse by gripping the neck or using a sling can cause traumatization that might erroneously suggest strangulation in subsequent autopsy. On the basis of 3 observations, postmortal damages which, at first sight, had seemed suspicious are presented and discussed. In the first case a drowned person's neck showed a dried skin line simulating a strangulation by ligature. The 2nd case dealt with a male person who had died ventricumbent in consequence of an apoplectic cerebral haemorrhage, and who had been lifted by embracing the neck shortly after death; at the post-mortem examination, massive blood extravasations were found in the cervical musculature. In the 3rd case, a strap was slung around the neck of a male epileptic--subsequently found to have served for carrying a saxophone. Both great hornes of the thyroid cartilage were fractured. Inquiry revealed that the undertakers had used the sling to hoist the corpse in which changes due to decomposition had already developed.

Adult↗
PubMed1989

[Fatal dog bite injuries].

In the absence of her parents, a girl of 4 months was killed by a 2-year old male Rottweiler dog belonging to the same family. The dog's front teeth left marks of individual, circular or scratch-like abrasions as well as slit-like severances of the skin, arranged in curved lines. The pattern of the skin-lesions largely correspond to the anatomy of the dog's set of teeth. No tissue defects (effects of devour) could be detected. Multiple traumatization of the trunk had led to serial rib fractures and ruptures of several organs.

Animals↗
PubMed1989

[Morphologic aspects of angle grinder injury].

Experiments were conducted on soft-tissue and bone preparations to determine the morphological characteristics of angle grinder injuries. The grinding effect of the rotating cutting-off wheel causes severances with local loss of tissue, resulting in tool-specific wound features. Superficial skin notches and (incomplete) severances of bony structures are of particular significance. Mutual trace transfer is a valuable means for determining the tool used and for interpreting the scene.

Accidents↗
PubMed1989

[A gas water heater as a means of suicide].

Report on two suicidal deaths by carbon monoxide, deriving from the exhaust fumes of gas water heaters. In the first case the exhaust system intentionally had been disconnected. In the second case a gas water heater with known defect (largely obstructed burner) acted as source of carbon monoxide; it had caused an accidental death some weeks before. Both suicides were aware that incomplete combustion of natural gas produces carbon monoxide. In one of the cases the CO poisoning remained undetected until autopsy.

Adult↗
PubMed1988

[Teeth as an intermediate target--a cause for rapid disintegration of the full metal-jacketed bullets used by the military].

Sharp-pointed full metal-jacketed bullets fired from assault rifles are expected to have a low tendency of deformation or destruction within biological tissues. In principle this also should apply to small calibre projectiles .223. If a bullet penetrates the oral region, contact with teeth can cause early break up and even total disintegration of the projectile. Under such circumstances the fragments are possibly retained within the body. A case of accidental gunshot injury to the head inflicted with an assault rifle AUG Steyr. 223 of the Austrian army serves to demonstrate and discuss the wound ballistic effects in relation to the altered behaviour of the projectile. Analogous findings were reproduced in experimental models.

Adult↗
PubMed1988

Pediculosis capitis: why prefer a solution to shampoo or spray?

Two hundred and sixty-eight children with pediculosis capitis took part in a comparative study to test the efficacy of five different pediculocides commonly used in Israel. The preparations used were pyrethrin shampoo, pyrethroid spray, malathion solution, carbaryl shampoo and carbaryl lotion. Carbaryl lotion and malathion solution were much more efficient when compared to the shampoo and spray preparations.

Carbaryl↗
PubMed1988

Value of looking at leukocytes in every case of ichthyosis.

A three-year old patient had ichthyosis and neutral lipid storage disease (Chanarin-Dorfman syndrome), characterized by congenital ichthyosiform erythroderma and leukocyte vacuoles. He did not show any of the internal system involvement that was found in previously described cases. Patients with this syndrome demonstrate a great variability of clinical involvement. The affliction may be very mild as in our case or it may lead to rapid death, as with the patient's brother born a Harlequin baby, who only survived 5 days. Because of this wide spectrum of clinical variability mild cases might escape diagnosis. It is, therefore, suggested that every case of ichthyosis should have a peripheral blood smear evaluation with special attention to the morphology of the leukocytes. Our case clearly demonstrates the value of such a screening examination. Although the patient had been under treatment for almost 3 years, only screening examination of blood smears of all the patients with ichthyosis finally led to the correct diagnosis.

Child, Preschool↗
PubMed1987

[Morphologic peculiarities in gunshot injuries of the aorta].

The characteristic appearance of gunshot injuries to the aorta is presented on the basis of 5 autopsy cases. (1) In sections showing no atherosclerotic changes, projectiles from hand weapons and from .22 calibre rimfire rifles leave remarkably small holes (comparable to the orifices of the intercostal arteries); in areas with sclerotic plaques the bullet holes are considerably larger. (2) Tears of several millimetres in length radiate from the entrance and exit perforations, so that the lesions may appear as stellate lacerations. The configuration of ante-mortem injuries was reproducible in test shots on aortas removed post mortem. The morphological findings can be explained by the ballistic wound response of elastic tissues.

Adult↗