Endotoxin-induced suppression of erythropoiesis: the role of erythropoietin and a heme synthesis stimulating factor

The regulation of erythropoiesis is primarily controlled by erythropoietin (Ep). Recently, however, other factors that both stimulate and inhibit erythropoiesis have been reported. Using an in vitro liquid culture of bone marrow cells, a factor in normal mouse serum was demonstrated that markedly stimulated heme synthesis by marrow erythroid cells. In this study, the role of this heme synthesis stimulating factor (HSF) and Ep in the erythropoietic suppression caused by endotoxin administration to mice was examined. Although HSF levels did not alter appreciably after endotoxin injection, marrow erythroid cells from these animals became unresponsive to the factor. This could be reversed if Ep was added to the culture in vitro or if the hormone was injected into the mice 18 hr prior to harvesting the marrow. This marrow erythroid cell response is identical to that seen in animals in whom Ep levels are markedly reduced, such as that found in exhypoxic polycythemia, and suggest a decrease in the hormone following endotoxin administration. Additional studies demonstrated that when Ep was injected into mice 6 hr after endotoxin administration, an increase in femoral erythroid colony-forming units (CFU-E), proerythroblast number, and 59 Fe incorporation into femoral marrow cells could be demonstrated. These findings, together with the marrow erythroid cell response to the hormone, suggest that the mechanism for suppression of erythropoiesis after endotoxin injection is a reduction in the level of circulating Ep.     

Clinical investigation of human alpha interferon in chronic myelogenous leukemia

Fifty-one patients with previously untreated or minimally treated chronic myelogenous leukemia in chronic phase received human alpha interferon 3 to 9 X 10(6) units intramuscularly (IM) daily until complete hematologic remission, then at doses ranging from 3 X 10(6) units every other day to 9 X 10(6) units daily. Forty-one (80%) patients achieved a hematologic response, 36 (71%) of them attaining a complete hematologic remission with normal peripheral WBC and differential counts. Responding patients showed continuous but slow normalization of several other blood and marrow parameters including platelet counts, serum lactic dehydrogenase and B12 levels, and marrow cellularity and maturation index. Suppression of the Philadelphia chromosome on serial cytogenetic studies of marrow metaphases was documented in 20 of the 36 patients who achieved complete hematologic remission (56%; 39% of total group), eight of whom (22%) had a decrease of the Philadelphia chromosome-positive metaphases to less than 35%. These changes were persistent for 6 months or longer in 18 patients, seven of whom had continuous suppression of the Philadelphia chromosome to less than 90% for a median of 30+ months (range 21+ to 39+ months). After a median follow-up period of 37 months, 25 patients remain in continued disease control with interferon therapy. The projected 3-year survival rate is 76%, with a yearly death rate of 6%, 9%, and 9% in the first 3 years. Response, Philadelphia chromosome suppression, and survival were significantly better among patients in the low-risk category compared to intermediate- and high-risk categories, as defined by a multivariate analysis-derived prognostic model. The projected 3- year survival rate was 94% for patients who achieved a complete hematologic remission on interferon therapy and 45% for those who did not. Thirteen patients have developed blastic crisis, six with lymphoid and three with undifferentiated morphology. We conclude that human leukocyte alpha interferon effectively controls chronic myeloid leukemia and allows reappearance of diploid hemopoietic cells in some patients.     

Evaluation of drugs for elimination of leukemic cells from the bone marrow of patients with acute leukemia

Relatively nonmyelotoxic drugs and drug combinations were investigated for their ability to eliminate malignant cells from human bone marrow. In vitro 90% inhibitory concentration (IC90) doses were established on granulocyte macrophage colony-forming units (GM-CFU) in culture of bone marrow by using the GM-CFU assay for the following drugs: 4- hydroperoxycyclophosphamide (4-HC), Adriamycin, L-asparaginase, bleomycin, hydrocortisone, VP-16, spirogermanium, Taxol, and vincristine. The leukemic cell kill efficiency of these drugs at IC90 doses was compared with that of 4-HC on acute lymphoid leukemia (ALL) cell lines by using the limiting-dilution assay. Under these conditions, no single drug was superior to 4-HC. To increase the in vitro effect in leukemic cell kill, combinations of vincristine with hydrocortisone, Adriamycin, VP-16, and 4-HC were investigated. Vincristine at 1 to 5 micrograms/mL increased the marrow cytotoxicity of hydrocortisone, Adriamycin, and VP-16, but it was protective (subadditive) with 4-HC. Vincristine and 4-HC in combination was additive to supraadditive on ALL cell lines, increased the leukemic cell kill by one to two logs above 4-HC alone at IC90 doses (P less than .05), and was not affected by the addition of excess marrow cells. The recommended doses for chemopurging in clinical studies are vincristine, 1 to 5 micrograms/mL, plus 4-HC, 5 micrograms/mL.     

Phosphate homeotasis in healthy subjects during prolonged periodic and continuous hypokinesia

OBJECTIVE: This study aimed to show that during hypokinesia (HK), phosphate (P(i)) imbalance increases more with higher than lower physical activity and that P(i) absorption reduces more with higher than lower P(i) imbalance in subjects with higher than lower muscular activity. METHODS: Studies were conducted on 30 healthy male subjects during 364 days of HK. They were equally divided in three groups: unrestricted active control subjects (UACS), continuously hypokinetic subjects (CHKS) and periodically hypokinetic subjects (PHKS). CHKS were kept under average walking distances of 0.5+/-0.2 km day(-1) PHKS were kept under average walking distances of 0.5+/-0.1 and running average distances of 8.7+/-1.2 km day(-l) for 5 days and 2 days per week, respectively. UACS were placed under average running distances of 8.7+/-1.2 km day(-l). RESULTS: P(i) imbalance, serum, urine and fecal P(i) levels, and urine and serum calcium (Ca(2+)) levels increased significantly (p<0.05) and P(i) absorption, and serum intact parathyroid hormone (iPTH) and 1,25-dehydroxyvitamin D (1,25 (OH)(2) D(3)) levels decreased significantly (p<0.05) in CHKS and PHKS compared with their pre-HK values and their respective active control (UACS). However, the P(i) imbalance, serum, urine and fecal P(i) levels, and serum and urine Ca(2+) levels increased more significantly (p<0.05), and P(i) absorption and serum iPTH and 1,25 (OH)(2) D(3) levels decreased more significantly in PHKS than in CHKS. CONCLUSIONS: Higher P(i) imbalance with higher than lower physical activity shows that the risk of higher P(i) imbalance is inversely related to the intensity of physical activity. Lower P(i) absorption with higher than lower P(i) imbalance shows that the risk of lower P(i) absorption is inversely related to magnitude of P(i) imbalance. In conclusion P(i) imbalance increases more with higher than lower physical activity and that P(i) absorption decreases more with higher than lower P(i) imbalance indicating that during HK the use of P(i) decreases more with higher than lower physical activity.     

Migraine and the hypothalamus

Migraine is a complex brain disorder where several neuronal pathways and neurotransmitters are involved in the pathophysiology. To search for a specific anatomical or physiological defect in migraine may be futile, but the hypothalamus, with its widespread connections with other parts of the central nervous system and its paramount control of the hypophysis and the autonomic nervous system, is a suspected locus in quo. Several lines of evidence support involvement of this small brain structure in migraine. However, whether it plays a major or minor role is unclear. The most convincing support for a pivotal role so far is the activation of the hypothalamus shown by positron emission tomography (PET) scanning during spontaneous migraine attacks. A well-known theory is that the joint effect of several triggers may cause temporary hypothalamic dysfunction, resulting in a migraine attack. If PET scanning had consistently confirmed hypothalamic activation prior to migraine headache, this hypothesis would have been supported. However, such evidence has not been provided, and the role of the hypothalamus in migraine remains puzzling. This review summarizes and discusses some of the clues.     

von Willebrand factor-collagen binding activity is increased in newborns and infants

ABSTRACT. von Willebrand factor (vWF) antigen (vWF:Ag) and vWF-collagen binding activity (vWF:CBA) were measured in plasma by parallel quantitative ELISAs in normal newborns and infants ( n =71). The medians for vWF:Ag (IUjml) and vWF:CBA (Ujml), respectively, were 1.46 and 1.91 for 2-7 day-old (n = 43), 1.22 and 1.40 for 2-4 week-old (n = 14), 1.22 and 1.15 for 2-6-month-old (n = 14) infants and 0.98 and 1.08 (n = 36) in normal adults. Elevated levels of vWF:Ag, but particularly vWF:CBA were seen for up to 4 weeks of life reaching adult levels between 2 and 6 months of life. The elevated levels of the vWF parameters indicate that caution should be exercised when interpreting laboratory data and diagnosing von Willebrand disease in newborns and young infants and warrant the use of age-specific reference ranges. The efficient haemostasis observed during early neonatal life may in part be due to the increased ability of vWF to interact with collagen.     

Selenium status of New Zealand infants fed either a selenium supplemented or a standard formula

Objective: New Zealand soils are deficient in the essential micronutrient, selenium. New Zealand infants have low selenium levels at birth and experience a further decline if fed cows milk based formula. This study examined the selenium status of infants fed with a new commercially available selenium supplemented formula.
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age.     

Dysgerminoma of the ovary: A retrospective study

A retrospective analysis of 22 patients with ovarian dysgerminoma who were treated between 1980 and 1987 was carried out. The median age at presentation was 24.5 years. A total of 15 patients were in stage I, one patient was in stage II and six patients were in stage III. Bilateral ovarian involvement was present in four patients. Conservative surgery was carried out in nine patients and 11 patients underwent radical surgery. Two patients had biopsy only. Fourteen patients received adjuvant radiotherapy and three patients received salvage radiation for recurrent disease. The 10-year actuarial survival rate was 81.8%. All 15 patients in stage I were alive and disease-free at a median follow-up of 125 months. Four patients (one in stage II and three in stage III) died of progressive or recurrent abdominopelvic disease. Pelvic recurrence occurred after conservative surgery in two patients in stage IA who had a tumour size greater than 10 cm, but they were salvaged with radical surgery, chemotherapy and radiotherapy. There were seven patients aged 20 years or less. All were alive and disease-free at a median follow-up of 127 months.