Balancing of energy-consuming processes of rat hepatocytes

A method for the quantification of energy consuming processes described by Siems et al. for reticulocytes and by Müller et al. for ascites tumour cells was applied to balance the ATP-consumption of isolated rat hepatocytes. On the basis of decreased coupled respiration rates following the specific inhibition of energy-requiring reactions, the energy demands of protein turnover, nucleic acid synthesis, Na+/K(+)-ATPase and Ca2(+)-transport of hepatocytes in different incubation media were assessed. These processes together with urea synthesis account for about 60 per cent of the total energy consumption in a glucose and amino acid-enriched Eagle/Borsook medium. The metabolic flux rates of total ATP-consumption and ATP-consumption of single energy-requiring processes in hepatocytes are compared with those in reticulocytes and different tumour cell types.

A prospective study of haemostatic parameters in relation to the clinical course of myeloproliferative disorders

Platelet function and the clinical course of the disease were prospectively investigated in 29 patients with myeloproliferative disorders. Serial determinations (median: 5 investigations per patient within 17 months) of platelet aggregation, plasma and intraplatelet concentrations of beta-thromboglobulin (beta TG) and platelet factor 4 (PF4), and of fibrinopeptide A (FPA) plasma levels were carried out. In the chronic phase of polycythaemia vera, patients with thrombohaemorrhagic complications during the study period had higher platelet count, more severe platelet aggregation defects, and increased plasma levels of beta TG and FPA compared to patients without complications. However, thrombohaemorrhagic complications were not predicted by changes in these parameters in the individual patient during the chronic disease phase. When patients with chronic myelogenous leukaemia entered blast crisis, bleeding complications were related to thrombocytopenia, impaired platelet function and low intraplatelet concentrations of beta TG and PF4. Cytoreduction by chemotherapy in the chronic phase of CML did not alter beta TG and PF4 plasma levels, whereas treatment of polycythaemia rubra vera by venesection favourably influenced platelet alpha-granule secretion and increased intraplatelet concentrations of beta TG and PF4.

Influence of splenectomy on platelet morphometry and function

Functional and morphometric platelet abnormalities may be influenced by splenectomy and thus contribute to postoperative thrombohaemorrhagic complications, especially in patients with splenomegaly and/or platelet defects. We investigated platelet function, platelet secretion, and platelet morphometry before and one week after splenectomy in seven patients with normal platelet production and normal spleen size (Hodgkin's disease) and five patients with splenomegaly and platelet abnormalities (4 with myeloproliferative disorders and 1 with chronic myelomonocytic leukemia). Severe postoperative thrombohaemorrhagic complications occurred only in patients with myeloproliferative disorders, although platelet count and mean platelet volume increased in almost all patients after splenectomy. Four patients with myeloproliferative disorders had impaired platelet aggregation before splenectomy that improved in only one patient after surgery. Platelet buoyant density in this patient group was decreased before splenectomy and normalised thereafter. Concomitantly, intraplatelet concentrations of alpha-granular proteins increased. Before splenectomy, there was a positive correlation between platelet density and platelet volume in patients with Hodgkin's disease (r = 0.59, p less than 0.001), but not in patients with myeloproliferative disorders. There was no correlation between platelet density and platelet volume after splenectomy in either patient group. In conclusion, morphometric platelet abnormalities were found in all patients after splenectomy. In patients with myeloproliferative/myelodysplastic disorders, decreased platelet buoyant density normalised and intraplatelet concentrations of alpha-granule proteins were elevated after splenectomy. However, platelet function defects in this patient group were not corrected and may have been a major cause of thrombohaemorrhagic complications in the postoperative period.

Refractory and relapsing Hodgkin's disease: role of high-dose chemotherapy with bone marrow transplantation

Thirty percent of adult patients with Hodgkin's disease fail primary treatment or relapse after treatment. Whereas overall mortality for Hodgkin's disease is about 20%, half the patients who relapse will die. Among patients with refractory or relapsing disease, about a third can be rescued by conventional salvage treatment. Unfortunately, except for patients with late relapse, remission after conventional salvage treatment is generally not of long duration. However, durable complete remissions can now be achieved in nearly a third of patients with refractory or relapsing disease by means of very aggressive (myeloablative) chemotherapy with consecutive autologous bone marrow transplantation (aBMT). The rate of durable complete remissions seems to be even higher if previous exposure to chemotherapeutic agents is not in excess of two different treatment protocols (optimal timing of aBMT) and if responsiveness to cytotoxic drugs is preserved (low degree of drug resistance). Bone marrow transplantation should be restricted to patients whose resulting long-term prognosis justifies such radical treatment. Reflecting ongoing clinical therapy-studies, in particular in Germany, the role of bone marrow transplantation in a general concept of salvage treatment should be pointed out. Patients should be considered candidates if they fail alternating primary chemotherapy or develop an early relapse after this treatment, but still show responsiveness to chemotherapeutic agents.

Children's understanding of cognitive cuing: how to manipulate cues to fool a competitor

4-6-year-old children's understanding of cognitive cuing was studied in 2 experiments using a strategic interaction paradigm. Children could fool a competitor by hiding targets in locations that were labeled with semantically weakly associated cues and help a cooperative partner by hiding them in semantically highly associated locations. Very few 4-year-olds, half the 5-year-olds, and almost all 6-years-olds appropriately chose semantically highly vs. weakly associated hiding places to make the targets easy vs. difficult to find. The second experiment showed that 4-year-olds did not strategically manipulate cues as sources of information, although they themselves proficiently used them as such in a search task. These findings are discussed with regard to research on children's developing understanding of origins of knowledge and belief and with regard to recent claims that young preschoolers possess a metacognitive understanding of cognitive cuing.

Developmental regulation of murine mammary progesterone receptor gene expression

Previously we have shown that in normal murine mammary glands progesterone receptor (PgR) levels are modulated as a function of development and differentiation such that lactating mammary glands do not contain detectable levels of PgR as measured by steroid binding. The objective of the present study was to determine whether the lack of steroid binding in lactating mammary glands was due to the absence of receptor protein and if so whether it was accompanied by an alternation in the pattern of PgR gene expression. Accordingly, we have performed an immunological analysis of murine mammary PgR isolated from different developmental states and have also examined these tissues for PgR gene expression. In mammary tissues from all developmental states other than lactation, immunoreactive PgR corresponding to both A and B forms of the protein were detected. Analysis for PgR mRNA revealed multiple species in mammary tissues and the relative order of abundance of the various transcripts and their sizes were approximately 6.9 greater than 8.7 greater than 3.5 greater than 2.7 greater than 4.2. The 6.9 and 8.7 kilobase transcripts accounted for between 70-80% of total mRNA. All five species of mRNA were detected in tissues from nulliparous mice which decreased dramatically during pregnancy, became undetectable during lactation, and were once again detectable in tissues from mice undergoing lactational involution. Experiments designed specifically to examine the effect of estradiol on mammary PgR mRNA revealed that in contrast to tissues from other developmental states, lactating mammary glands were unable to respond to estradiol with an increase in PgR mRNA. Based on these findings and the fact that estrogenic insensitivity of lactating mammary glands coexists with the presence of ER we propose that in this tissue there is an alteration in the estrogen dependent transcriptional regulation of PgR gene expression.

Relationship of thrombin generation to peripheral blast cell count in patients with acute myeloblastic leukemia (AML)

Disseminated intravascular coagulation (DIC) commonly occurs in patients with acute promyelocytic leukemia (APL, FAB-M3) but may also be seen in other subtypes of AML. DIC in patients with AML has been attributed to procoagulants released from granular fractions of leukemic blast cells. The present study was designed (i) to evaluate thrombin activity in patients with AML by measuring plasma levels of fibrinopeptide A (FPA) prior to chemotherapy, and (ii) to examine whether a relationship between FPA levels and the number of peripheral blast cells exists. Plasma levels of FPA were determined using a commercially available RIA kit. To remove fibrinogen and the majority of elastase-induced fibrinopeptides (A alpha 1-21) known to crossreact with the FPA (A alpha 1-16) antiserum used in this assay, plasma samples were treated with bentonite prior to further processing. The study was conducted on 5 patients with APL and on 22 patients with other subtypes of AML. Peripheral blast cell counts at initial diagnosis ranged from 2100 to 56,000/microliters in patients with APL and from 1900 to 151,000/microliters in patients with other AML subtypes. The mean (+/- 1 SEM) pretreatment plasma level of FPA was significantly higher (p = 0.021) in the 5 patients with APL (38.2 +/- 8.3 ng/ml) than in patients with other AML subtypes (8.1 +/- 0.7 ng/ml). No relationship was found between peripheral blast cell counts and the corresponding FPA levels in the total group of 27 patients. However, when considering the 5 patients with APL separately, a significant correlation was observed between peripheral blast cell number and FPA plasma levels (r = 0.88, p = 0.050). This study confirms that thrombin generation is considerably greater in patients with acute promyelocytic leukemia than in other subtypes of AML. We conclude that type and number of circulating blast cells and their related capacity to express procoagulant activities appear to be major determinants of excessive fibrinogen degradation in AML.

Inhibition of rat heart allograft rejection by a PUVA treatment of the graft recipient. Role of cisurocanic acid

Treatment of rat heart grafts with PUVA, the combination of the photosensitizer 8-methoxypsoralen and longwave ultraviolet light, leads to a prolonged transplant survival in allogeneic recipients. A PUVA treatment of the recipient rats, performed for 7 consecutive days after transplantation, prolonged graft survival even more effectively. This may be due to the systemic immunomodulatory effects of PUVA in the recipient. One of the mediators is urocanic acid, which is transformed by ultraviolet light in the skin from its trans- to the cis-isomer, which, in turn, acts as a mediator on the immune system. An injection of cisurocanic acid into graft recipients for 7 consecutive days after transplantation resulted in prolonged graft survival; in 40% of the rats, permanent graft acceptance was observed. The significance of these results for clinical organ transplantation is discussed.

Haemodynamic and metabolic effects of xamoterol in exercising dogs

The effects of xamoterol on the haemodynamic adaptation to graded treadmill exercise were evaluated during five subsequent cycles in chronically instrumented dogs. At rest xamoterol, 0.2 mg/kg i.v., preferentially showed a positive inotropic effect, whereas 1 mg/kg i.v. also exhibited a marked chronotropic effect. The cardiac output and left ventricular power increased dose dependently. The mean left atrial pressure and total peripheral resistance decreased concomitantly. Xamoterol did not produce a noteworthy decrease in heart rate or positive dp/dtmax during exercise, even at a dosage of 1 mg/kg. A beta-adrenoceptor blocking effect could only be seen from the diminution of the exercise-induced changes in heart rate, dp/dtmax, cardiac output, left ventricular power and total peripheral resistance. Determination of the blood glucose, lactate and pyruvate levels before the start of each exercise cycle revealed that the drug induced a decrease in blood glucose and an increase in blood pyruvate. Thus, xamoterol exerted a dose-dependent sympathomimetic effect in dogs at rest. However, there was little evidence for a beta-adrenoceptor blocking action even at higher work loads, although preliminary experiments in conscious dogs showed that xamoterol shifted the isoprenaline dose-response curve to the right by a factor of 1.31 (0.2 mg/kg) and 3.05 (1 mg/kg).

Concentrations of isosorbide dinitrate, isosorbide-2-mononitrate and isosorbide-5-mononitrate in human vascular and muscle tissue under steady-state conditions

The concentrations of isosorbide dinitrate (ISDN), isosorbide-5-mononitrate (IS-5-MN) and isosorbide-2-mononitrate (IS-2-MN) were determined in plasma (PL), saphenous vein wall (SV) and pectoral muscle (PM) from 8 patients undergoing coronary bypass surgery. The patients were pretreated for 2 days with ISDN 240 mg per day (standard release formulation) in 4 doses of 40 mg and one dose of 80 mg. The plasma and tissue samples were obtained during the operation, 10-12 h after the last dose. Isosorbide-2-mononitrate and isosorbide-5-mononitrate were present in plasma and tissues in the same concentration ranges with molar concentration ratios of 0.88 (IS-2-MN: PM/PL), 0.85 (IS-5-MN: PM/PL), 0.99 (IS-2-MN: SV/PL) and 1.06 (IS-5-MN: SV/PL). Mean ISDN concentrations in tissue were considerably higher than in plasma; the molar concentration ratios were 4.9 (SM/PL) and 7.21 (SV/PL). The accumulation of ISDN in vessel walls may contribute to its greater vascular action compared to the mononitrates, but it may also facilitate the development of tolerance during long-term treatment.

Clinical evaluation of hypothermic ventricular fibrillation, multi-dose blood cardioplegia, and single-dose Bretschneider cardioplegia in coronary surgery

37 patients undergoing coronary revascularization were randomly assigned to three protocols for intraoperative myocardial protection: hypothermic ventricular fibrillation (HF) (n = 13), multi-dose blood cardioplegia (BCP) (n = 12) and single-dose Bretschneider's crystalloid cardioplegia (CCP) (n = 12). As intraoperative markers of ischemic damage myocardial ultrastructure, ATP, and CP contents were determined in left ventricular biopsy specimens taken before and after cardiac arrest. Release of serum enzymes (CK, CK-MB, LDH, SGOT) was determined pre- and postoperatively. Hemodynamic data were assessed before, during, and after operation. The incidence of low cardiac output, positive inotropic support, intraaortic balloon counterpulsation, peri-operative myocardial infarction, rhythm disturbances, and the rate of spontaneous defibrillation was compared between groups. The results show a better preservation of high energy phosphates in the BCP group as compared to the HF and CCP groups. Myocardial ultrastructure showed moderate ischemic damage in the hypothermic fibrillation group; in contrast, only slightly deteriorated cells were seen after cardiac arrest, when cardioplegia was used. The incidence of rhythm disturbances was 25% for HF and 42% for CCP. In contrast, only 17% of new rhythm disturbances were seen in the BCP group. Functional recovery (i.e. CI and SWI) of hearts protected with BCP was generally greater as compared to HF and CCP. Release of MB-creatine-kinase isoenzyme was higher in the HF group as compared to cardioplegia. Clinical outcome in terms of incidence of peri-operative infarction, positive inotropic support and low cardiac output was superior in the BCP group but not significantly different between groups.(ABSTRACT TRUNCATED AT 250 WORDS)

[Immunohistologic differentiation of interstitial infiltration cells in biopsies of transplanted kidneys]

Despite known morphological criteria of kidney allograft rejection a definite diagnosis of interstitial rejection in not possible in each case. Therefore, by an enzyme histological differentiation of infiltrating cells in the transplant biopsy specimen this problem should be solved. It was used the PAP method against pan T lymphocytes, T4 and T8 lymphocytes, monocytes and granulocytes. An acute interstitial rejection can be verified if 1. the number of lymphocytes and their subpopulations did increase over the maximum values, 2. without vascular rejection is the T4/T8 ration less than 1 and 3. in the presence of vascular rejection is the T4/T8 ratio greater than 1. Additional information about cyclosporin injury or viral infections may be possible. It is possible increase markedly the rate of safer diagnosis by immunohistological differentiation of infiltrating cells.

Septicemia due to Streptococcus mitis in neutropenic patients with acute leukemia

Eight neutropenic patients with acute lymphocytic or nonlymphocytic leukemia had septicemia due to different strains of Streptococcus mitis (St. mitis), a microorganism not commonly recognized as a special pathogen in leukemic patients. Four of the patients had been treated with high-dose cytosine arabinoside as part of the cytostatic regimen, six had a central venous line and four patients had oral lesions prior to the infection. Selective gut decontamination consisted of co-trimoxazole/colistin in five patients and quinolones in three patients. The first three patients died, either due to interstitial pneumonia with the adult respiratory distress syndrome (ARDS), or due to infection-triggered disseminated intravascular coagulation despite prompt empiric antibiotic therapy including vancomycin. The other patients improved after empiric supplementation of penicillin G (30 Mega/day) to the antibiotic regimen. Beginning ARDS in two of these patients dramatically responded to high-dose steroids. We conclude that St. mitis is a major pathogen in neutropenic leukemic patients. Infection appears to occur independently of acute leukemic cell type, regimen of selective gut decontamination, venous access, visible oral lesions or treatment with high-dose cytosine arabinoside. The clinical course of our patients raises questions about the value of commonly recommended empiric antibiotic regimens, which were clearly ineffective to control infections with St. mitis in this patient group. Our data indicate that immediate antibiotic therapy with penicillin G is indicated and may be life-saving for suspected St. mitis infections in neutropenic leukemic patients.

Two types of acquired idiopathic sideroblastic anaemia (AISA)

On cytological bone marrow examination we distinguished between pure sideroblastic anaemia (PSA), which is confined to dyserythropoiesis, and refractory anaemia with ring sideroblasts (RARS), which is characterized by additional dysplastic features of granulopoiesis and/or megakaryopoiesis. In a follow-up study of 94 patients with AISA diagnosed according to FAB criteria for myelodysplastic syndromes we found a striking difference in the risk of leukaemic transformation between PSA and RARS (5 year cumulative rate 1.9% v. 48%). Overall survival was much better in PSA than in RARS (5 year cumulative chance 69% v. 19%). Infections and haemorrhages were frequent causes of death in RARS but not in PSA. Bone marrow culture studies (CFU-GM) were performed on 10 consecutive patients with PSA and RARS, respectively. RARS patients showed grossly impaired colony growth, typical of the myelodysplastic syndromes. Patients with PSA had persisting colony formation, even if moderately decreased in frequency, with numbers of CFU-GM being inversely correlated with the degree of erythroid hyperplasia in the bone marrow. We conclude that on cytomorphological grounds AISA can be divided into pure (dyserythropoietic) sideroblastic anaemia (PSA) and a true myelodysplastic form (RARS), with both types differing considerably in terms of survival, risk of leukaemic transformation and findings on bone marrow culture (CFU-GM).