The Clinical Spectrum of Renal Insufficiency During Acute Glomerulonephritis in the Adult

Twenty-seven adults with acute poststreptococcal glomerulonephritis were divided into two groups according to the severity of reduction in renal function: (1) 14 patients with mild depression of renal function, and (2) 13 patients with more severe renal insufficiency. In the first group the outcome was favourable, with complete clinical recovery in 11 patients. Only two patients in the second group have recovered. Five have died of renal failure and in six the chronic stage has developed. The most notable histopathological lesion observed in this group of patients was severe proliferative glomerulonephritis with a large number of epithelial crescents. According to the mode of development and time of onset of renal failure, these 13 patients could be divided into three sub-groups: (1) early renal failure without oliguria (three patients), (2) early renal failure with severe oliguria or anuria (three patients) and (3) delayed renal failure (seven patients).Although there are exceptions, the development of renal insufficiency in an adult patient suffering from acute glomerulonephritis is usually associated with a guarded prognosis.     

Influence of purified recombinant human macrophage colony stimulating factor in mice

The endotoxin-resistant strain of mouse, C3H/Hej, was assessed for hematological responsiveness to multiple injections of high dosages of purified recombinant human macrophage colony stimulating factor (rhu-M-CSF). Mice were administered the rhu M-CSF i.p. at dosages of 40 micrograms per injection, 2 or 3 times per day for 4 days. This resulted in significant increases in circulating leukocytes compared to control mice given sterile pyrogen-free saline. Assessment of the marrow and spleen of these mice on the 5th day noted a significant reduction in the numbers of marrow hematopoietic progenitor cells, with no change in their cycling rates. In contrast, splenic granulocyte-macrophage and erythroid progenitor cell numbers were markedly increased and the cycling rates of these progenitors plus those of multipotential progenitors were significantly enhanced. Marrow and splenic early myeloid cells (blasts, promyelocytes, and myelocytes) and macrophages were increased, while marrow and splenic PMN were decreased. The results suggest that multiple injections of high dosages of rhu-M-CSF to previously untreated mice for a short period of time has a modest enhancing effect on blood leukocyte levels. This is associated with a shift of hematopoietic cell activity from the marrow to the spleen.     

Redox Properties Of Phenols, Their Relationships To Singlet Oxygen Quenching And To Their Inhibitory Effects On Benzo(A)Pyrene-Induced Neoplasia

The inhibitory effects of synthetic phenolic compounds on benzo(a)pyrene-induced neoplasia of the mouse forestomach have been measured by Wattenberg et al⁶ The efficiency of this inhibition has been estimated for each phenol, using R, the ratio of the number of tumors per mouse in the protected group over the number of tumours per mouse in the control group. We have observed a linear correlation between the chemoprotection efficiency R and the logarithm of the rate of quenching of singlet oxygen. k. by this family of phenols, log k being itself correlated with the one-electron oxidation potential of the phenols. These correlations suggest a charge transfer mechanism for the inhibition of neoplasia induced hy benzo(a)py-rene. The correlations described provide a theoretical basis for scaling the inhibitors of mutagenicity induced by polycyclic aromatic compounds in terms of their oxidation potentials     

Genetic variation of recent Alu insertions in human populations

The Alu family of intersperesed repeats is comprised of ovr 500,000 members which may be divided into discrete subfamilies based upon mutations held in common between members. Distinct subfamilies of Alu sequences have amplified within the human genome in recent evolutionary history. Several individual Alu family members have amplified so recently in human evolution that they are variable as to presence and absence at specific loci within different human populations. Here, we report on the distribution of six polymorphic Alu insetions in a survey of 563 individuals from 14 human population groups across several continents. Our results indicate that these polymorphic Alu insertions probably have an African origin and that there is a much smaller amount of genetic variation between European populations than that found between other populations groups. Present address: Department of Pathology, Stanley S. Scott Cancer Center, Louisiana State University Medical Center, 1901 Perdido St., New Orleans, LA 70112 Correspondence to: M.A. Batzer     

Phytotropin-binding sites and auxin transport in Cucurbita pepo: evidence for two recognition sites

Two properties of phytotropins, their ability to bind to 1-N-naphthylphthalamic acid (NPA) receptors located on microsomal vesicles isolated from Cucurbita pepo L. hypocotyls, and to stimulate auxin (indol-3-yl acetic acid, IAA) accumulation into such vesicles by blocking its efflux from them, were assessed in double labelling experiments using [2,3,4,5-³H]1-N-naphthylphthalamic acid and 3-indolyl-[2-¹⁴C]acetic acid. Two sites of differing affinities and activities on IAA accumulation were found. 1-N-Naphthylphthalamic acid was found to have high affinity (K_D at 10^-8mol·l^-1) for one site and low affinity (K_D at 10^-6 mol·l^-1) for the other, whereas 2-(1-pyrenoyl)benzoic acid displaced NPA with high efficiency (K_D below 10^-8 mol·l^-1) from both sites. Other phytotropins had intermediate affinities for either site. Occupation of the site with low affinity for NPA stimulated auxin accumulation, while occupation of the high-affinity site with a phytotropin did not interfere with auxin accumulation into vesicles.Abbreviations IAA Indol-3-yl acetic acid - NPA 1-N-naphthylphthalamic acid - PBA 2-(1-pyrenoyl)benzoic acid - TIBA 2,3,5-triiodobenzoic acid W.M. was supported in part by an allowance from CSIRO and in part by a fellowship of the Deutsche Forschungsgemeinschaft; he acknowledges the friendly hospitality of the CSIRO Division of Plant Industry. The authors thank R. Hertel (Freiburg) for valuable discussion.     

Cooperative interaction of reduced pyridine nucleotides with estrogen synthetase of human placental microsomes

The estrogen synthetase present in human placental microsomes appears to be dependent on the cooperative interaction of the reduced cofactors NADPH and NADH for optimal activity. Using steady-state concentrations of either cofactor, it was found that while the estrogen synthetase activity followed hyperbolic saturation kinetics with NADPH (K_mapp = 14 μM), the enzyme followed sigmoidal saturation kinetics when the cofactor was NADH, with the half-maximum velocity attained at a cofactor concentration of 1.1 mm. The maximum velocity obtained with NADPH as the cofactor was greater than with corresponding concentrations of NADH. Estrogen synthetase activity in the presence of NADH was not due to NADPH contamination. NADH, in the presence of small concentrations of NADPH (0.5 to 5 μm), stimulated significantly the rate of estrogen formation from androstenedione by placental microsomes and, in addition, the enzyme saturation kinetics changed from sigmoidal to hyperbolic, thus mimicking the effect of NADPH. Estrogen synthetase activity, measured in the presence of 1 mm NADH, was stimulated in a dose-dependent manner by NADPH (K_mapp = 0.4 μM NADPH) and, when the enzyme was measured in the presence of 5 μm NADPH, the activity was stimulated in a dose-dependent manner by NADH (K_mapp = 45 μM NADH). Estrogen synthetase activity measured in the presence of NADH, without and with NADPH (1 μm) remained linear both with time of incubation for approximately 15 min and with microsomal protein concentration up to 3 mg/ml. The apparent K_m of estrogen synthetase for androstenedione, when measured in the presence of NADH, was 1 μm. The synergistic interaction between NADH and NADPH in stimulating placental estrogen synthetase activity observed in vitro may, conceivably, take place in vivo in the intact placenta.     

Immunochemical reactivity of simian sarcoma virus polypeptides isolated by preparative sodium dodecyl sulfate polyacrylamide gel electrophoresis

The polypeptides associated with a zonal centrifugation purified simian sarcoma virus propagated in lymphoblastoid NC-37 cells were isolated by preparative polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS) using a procedure designed to minimize the loss of immunochemical reactivity. The proteins p10, p15, p28, p36, p44, p75, and p86 were obtained in large yield and high degree of homogeneity. The electrophoretically purified p28 was analyzed by competition radioimmunoassay using antiserum to a pore exclusion and ion exchange purified simian sarcoma virus p28. Complete competition was observed with extracts of simian sarcoma virus infected cells. No competition was observed with uninfected or unrelated, infected cell extracts. The antigen-antibody affinity as measured by the slope of the competition curve using antiserum to p28 and 125I-labeled and electrophoretically purified p28 was the same as that for the p28 released from sonication-disrupted simian sarcoma virus. The data indicates that preparative purifications by polyacrylamide gel electrophoresis in the presence of SDS may be generally applicable for the isolation of proteins with essentially the same immunospecificities and affinity for a specific antiserum as proteins isolated by procedures that avoid the use of SDS and electrophoresis.     

Analysis of Pleiotropism at the Dominant White-Spotting (W) Locus of the House Mouse: A Description of Ten New W Alleles

Characterization of the pleiotropic effects of ten new putative W locus mutations, nine co-isogenic and one highly congenic with the C57BL/6J strain, reveals a wide variety of influences upon pigmentation, blood formation and gametogenesis. None of the putative alleles, each of which is closely linked to Ph, a gene 0.1 cM from W, gave evidence of complementation with W³⁹, a new allele previously shown to be allelic to W^v. All W*/W³⁹ genotypes resulted in black-eyed-white anemics with reduced gametogenic activity.¹ Homozygotes for seven of these mutations are lethal during perinatal life; anemic embryos have been identified in litters produced by intercross matings involving each of these alleles.—Phenotypes of mice of several mutant genotypes provide exceptions to the frequent observation that a double dose of dominant W alleles (e.g., W/W^v or W/W) results in defects of corresponding severity in each of the three affected tissues. One viable homozygote has little or no defect in blood formation, and another appears to have normal fertility. The phenotypes of these homozygotes support the conclusion that the three tissue defects are not dependent on each other for their appearance and probably do not result from a single physiological disturbance during the development of the embryo.—Although homozygosity for members of this series results in a wide range of phenotypes, the absence of complementation of any allele with W³⁹, the close proximity of each mutant to Ph, and the fact that all alleles produce detectable (though sometimes marginal) defects in the same tissues affected by W and W^v, support the hypothesis that each new mutant gene is a W allele.     

Turnover kinetics of Photosystem I measured by the electrochromic effect in Chlorella

The rise kinetics of the absorption changes induced at 515 nm and 480 nm by a flash were studied using two types of xenon flashes of different durations. The ‘slow’ rise of the absorption change ($\text{t}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 15–20 μ}\text{s}$) observed by Cox and Delosme (1978 C.R. Acad. Sci. (Paris) Sér. D 282, 775–778) and Joliot P., Delosme, R. and Joliot, A. ((1977) Biochim. Biophys. Acta 459, 47–57) was found to be due to double hits occurring in the reaction centers of System I during the flash.The turnover kinetics of the reaction centers of System I after a short flash were studied by a double flash method. They are in agreement with a second order reaction between P⁺-700 and its electron donor.