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Biomedical subjects

K H Winterhalter

Publications and source records attributed to K H Winterhalter.

At least 163 records · Page 9Linked to original sources
PubMed1977

Modulation of the Root effect in goldfish by ATP and GTP.

Both ATP and GTP are present in considerable amounts in red cells of the common goldfish Carassius auratus. They both influence the Root effect of the single major fish hemoglobin, but GTP is, depending on pH, 2-6 times more effective than ATP. The two triphosphates account for 3/4 of the effect of trichloroacetic acid supernatant obtained from hemolysate which contains still some compound(s) which can influence the shift of the Root effect toward higher pH.

Adenosine Triphosphate↗
PubMed1975

[Normal erythropoiesis].

The organism has at least three different mechanisms for the modulation of oxygen supply to tissues: 1) respiratory-circulatory, 2) modification of oxygen dissociation of hemoglobin, 3) modification of oxygen transport capacity by increasing the volume of circulating red cells. The erythroid, granulocytic and thrombocytic cell lines originate from a common pluripotent stem cell. In the course of differentiation the erythroid precursor cell acquires the capability of responding to the humoral regulator of total red blood cell volume, erythropoietin. Furthermore, the ability develops to take up tightly bound iron from transferrin, to synthesize large amounts of hemin and to express the few structural genes for hemoglobin polypeptides preferentially. The effects of these phenomena are discussed in the framework of the erythron.

Biological Transport↗
PubMed1975

Electron-spin resonance of nitrosyl haemoglobins: normal alpha and beta chains and mutants Hb M Iwate and Hb Zürich.

At 77 K the electron spin resonance (ESR) spectra of the NO derivatives of the mutant haemoglobins Hb M Iwate and Hb Zurich as well as of the isolated chains of normal haemoglobin were studied. Two types of ESR spectra differing in the g-value and the hyperfine splitting at gzz were observed. The type II spectrum is characterized by a hyperfine structure at gzz = 2.005 with a splitting constant of deltaH = 23 G (14NO) or 32 G (15NO), respectively. In the type I spectrum the splitting constant of the hyperfine structure at gzz = 2.009 amounts to deltaH = 18 G (14NO) or 23 G (15NO), respectively. In some cases this hyperfine structure is coincident with another one at gxx = 2.064 with nearly identical splitting constant. In addition, the type I spectrum is characterized by an increased ESR absorption at gxx = 2.064. At neutral pH the NO derivatives of the isolated chains as well as of the mutant haemoglobins give rise to a type II spectrum. In correspondence with previous results gained with normal NO haemoglobin, the ESR spectra of the NO-alpha chains and NO-Hb Zurich show a transition to type I in the acid region. This transition is favoured by binding of 2,3-bisphosphoglycerate. On the other hand, the ESR spectra of the NO-beta chains and NO-Hb M Iwate are of the type II also at acid pH. The NO-beta chains show a transition of the ESR spectrum from type II to type I only at alkaline pH. These results indicate that in the tetrameric NO haemoglobin only the alpha chains are responsible for the transition of the ESR spectrum from type II to type I in the acid region. The two types of ESR spectra are interpreted in terms of two kinds of haem-NO complexes differing in the iron-NO and iron-imidazole distances. The type II spectrum is attributed to a complex with a relatively short iron-imidazole distance which is responsible for a weakened sigma-bond in trans position. The type I spectrum arises then from a complex with a larger iron-imidazole bond leading to an approach of the NO molecule to the iron. The influence of the protein conformation upon the iron-imidazole bond length is discussed with regard to the ESR spectra of the mutant NO haemoglobins and considering the influence of agents modifying the protein structure.

Electron Spin Resonance Spectroscopy↗
PubMed1975

A Swiss family with hemoglobin P Galveston beta117His leads to Arg, including two patients with hb P/beta thalassemia.

The mutant Hb P Galveston (beta117His leads to Arg) is observed in two heterozygotes for beta thalassemia and by itself does not cause clinical symptoms. Some of the physico-chemical properties of Hb P Galveston are identical to the onemical properties of Hb P Galveston are identical to the ones hemoglobin Zurich (beta 63 His leads to Arg) so that only a detailed analysis led to its proper identification.

Amino Acid Sequence↗
PubMed1975

[Severe light dermatosis following photo therapy in a newborn infant with congenital erythropoietic urophyria].

A newborn infant with hemolytic anemia and hepatosplenomegaly was treated by phototherapy for early jaundice. After 18 h, a dark brown pigmentation of the skin was noticed, leading to the assumption of a bronze baby syndrome. Indeed, the child was suffering from a severe disturbance of liver function. 4 days later, a severe bullous dermatosis with blody imbibition developed, covering all exposed parts of the body surface and reoccurring in many bursts over several weeks despite protection against light. A severe hemolytic anemia was constantly present. The baby died on the 50th day. The diagnosis of erythropoietic porphyria was suggested immediately after the onset of the bullous exanthema and proved by laboratory data as follows: uro- and coproporphyrin in the urine were extremely high, uroporphyrin being mainly of type-I isomer. In red cells, increased amounts of uro-, copro- and protoporphyrins were detected. Massive red fluorescence of erythroblasts (so-called porphyroblasts) in the bone marrow and in the blood could be observed. At autopsy, the liver showed multiple blood-forming areas and severe diffuse hemosiderosis, which is to be explained by a long existing, i.e. fetal hemolysis. Erythropoietic porphyria is such a rare disease that there is no reason to consider it as a general contraindication for phototherapy.

Bone Marrow Diseases↗