Three further naphthoquinones produced by Fusarium solani

Three naphthoquinone pigments are described which were produced by Fusarium solani. They are 2,3-dihydro-5,8-dihydroxy-6-methoxy-2-hydroxymethyl-3-(2-hydroxypropyl)-1,4-naphthalenedione, 2,3-dihydro-5-hydroxy-4-hydroxymethyl-8-methoxy-naphtho[1,2-b]furan-6,9-dione and 5,8-dihydroxy-2-methoxy-6-hydroxymethyl-7-(2-hydroxypropyl)-1,4-naphthalenedione. One of these pigments was shown to be the precursor of the other two.     

Cyclic adenosine 3'5' monophosphate stimulates prostaglandin E production by human adherent synovial cells

Production of prostaglandin E (PGE) by rheumatoid synovium appears important to regulation of the pathologic process in rheumatoid arthritis. Cells derived from human synovium by proteolytic digestion produce large amounts of PGE which in turn can elevate synovial cell cAMP levels and inhibit cell proliferation. Data presented here indicate that cAMP can further increase production of PGE from adherent synovial cells (ASC). PGE production occurs over 12-72 hr and is not due to the ability of cAMP to inhibit cell proliferation. Exposure of cells to cAMP results in increased release of 3H arachidonic acid from precursors but not in activation of the cyclooxygenase enzyme. This phenomenon suggests the presence in adherent synovial cells of a mechanism for amplifying PGE production.     

Inspiratory rhythm in airway smooth muscle tone

In anesthetized paralyzed open-chested cats ventilated with low tidal volumes at high frequency, we recorded phrenic nerve activity, transpulmonary pressure (TPP), and either the tension in an upper tracheal segment or the impulse activity in a pulmonary branch of the vagus nerve. The TPP and upper tracheal segment tension fluctuated with respiration, with peak pressure and tension paralleling phrenic nerve activity. Increased end-tidal CO2 or stimulation of the carotid chemoreceptors with sodium cyanide increased both TPP and tracheal segment tension during the increased activity of the phrenic nerve. Lowering end-tidal CO2 or hyperinflating the lungs to achieve neural apnea (lack of phrenic activity) caused a decrease in TPP and tracheal segment tension and abolished the inspiratory fluctuations. During neural apnea produced by lowering end-tidal CO2, lung inflation caused no further decrease in tracheal segment tension and TPP. Likewise, stimulation of the cervical sympathetics, which caused a reduction in TPP and tracheal segment tension during normal breathing, caused no further reduction in these parameters when the stimulation occurred during neural apnea. During neural apnea the tracheal segment tension and TPP were the same as those following the transection of the vagi or the administration of atropine (0.5 mg/kg). Numerous fibers in the pulmonary branch of the vagus nerve fired in synchrony with the phrenic nerve. Only these fibers had activity which paralleled changes in TPP and tracheal tension. We propose that the major excitatory input to airway smooth muscle arises from cholinergic nerves that fire during inspiration, which have preganglionic cell bodies in the ventral respiratory group in the region of the nucleus ambiguus and are driven by the same pattern generators that drive the phrenic and inspiratory intercostal motoneurons.     

Isolation and sequence analysis of a cDNA encoding the ATP/ADP translocator of Zea mays L.

A cDNA complementary to the mRNA for the ATP/ADP translocator of maize (Zea mays L.) has been identified by virtue of hybridisation with the homologous gene from yeast. The cloned cDNA has been shown by DNA sequence analysis to contain an open reading frame of 954bp., which encodes a polypeptide of molecular weight 40,519. This polypeptide exhibits a high degree of homology to the translocator polypeptides of beef heart and Neurospora crassa mitochondria.     

Diversity and zoogeography of marine Tubificidae (Annelida,Oligochaeta) with notes on variation in widespread species

The specific and generic diversities of the marine Tubificidae (Annelida, Oligochaeta) of the NE Pacific are compared to those of the NE and NW Atlantic as well as to those of Heron Island, Australia. Diversity in the NE Pacific is relatively high when compared to that of the NE Atlantic. The Tubificidae of the NW Atlantic (limited to the eastern coast of the USA) show two distinct zoogeographic regions: Florida to Cape Hatteras; Cape Hatteras to Massachusetts. Diversity, both in terms of the number of species and number of genera, is approximately the same in these two regions, and is similar to that of both the NE Pacific and Heron Island. Evidence suggests that the widespread marine species, in particular Tubificoides pseudogaster, have a range of morphotypes across their distributions. The apparent wide distributions of these species may be due to a taxonomy unable to resolve the differences between the morphotypes. The tubificid oligochaete fauna of the NE Atlantic appears impoverished compared to the other regions examined. The NE Pacific, NW Atlantic, and Heron Island regions are not dominated by one group of species while the NE Atlantic fauna is dominated by Tubificoides benedeni and Clitellio arenarius.     

Lectin-induced modulation of the antibody response to type III pneumococcal polysaccharide

Several lectins were tested for their capacity to alter the antibody response to type III pneumococcal polysaccharide (SSS-III). The antibody response was enhanced by concanavalin A (Con A), phytohemagglutinin (PHA), as well as lectins from Phytolacca americana (Pa-2), Pisum sativum (PSA), and Lens culinaris (LCH), when these lectins were given 2 days after immunization with SSS-III; however, suppression was obtained when Con A and Pa-2 were given at the time of immunization. By contrast the lectins from Vicia villosa (VVL) and Bauhinia purpurea (BPA) did not alter the antibody response. Since the lectins PSA and LCH bind to the same monosaccharide as Con A, whereas the other lectins bind to different monosaccharides, these findings indicate that there is no relationship between nominal monosaccharide specificity and the capacity to modulate the antibody response. Substantial increases in the magnitude of the IgG₁ antibody response was noted after the administration of Con A whereas profound enhancement of IgG_2a antibody response was noted after PHA was given.     

Appearance of a State 1 – State 2 transition during chloroplast development in the wheat leaf: Energetic and structural considerations

The ability of developing chloroplasts to dynamically regulate the distribution of excitation energy between photosystem 1 and photosystem 2, and thus perform a State 1 – State 2 transition, was examined from analyses of chlorophyll fluorescence kinetics in 4- and 8-day-old Triticum aestivum L. cv. Maris Dove leaves grown under a diurnal light regime. Chloroplasts at all stages of development in the two leaf systems could undergo a State 1 – State 2 transition, except those found in the basal 0.5 cm of the 4-day-old leaf. The ability to physiologically modify the excitation energy distribution between the chlorophyll matrices of the two photosystems developed after the development of mature, fully photochemically competent photosystem 2 units and the appearance of excitation energy transfer between photosystem 2 and photosystem 1. Also, changes in the degree of energetic interaction between the two photosystems, in vivo rates of electron transport and the chlorophyll a/b ratio could not be correlated with the appearance of a State 1 – State 2 transition. Ultrastructural studies demonstrated a 32% increase in the degree of thylakoid appression in chloroplasts at the base of the 8-day-old leaf compared to the situation in the basal 0.5 cm of the 4-day-old leaf. This difference in thylakoid stacking can account for the differing abilities of these two tissues to perform a State 1 – State 2 transition when considered in the context of the distribution of the two photosystems within appressed and non-appressed regions of thylakoid membranes.     

Density gradient characterization of the high density lipoproteins in cholesterol-fed hyper- and hyporesponding patas monkeys (Erythrocebus patas)

Diet-induced changes in high density lipoprotein (HDL) density and size were studied in patas monkeys. When the animals were switched from a moderate fat-low cholesterol diet to a high fat-high cholesterol (HFHC) diet, the plasma apoA-I levels increased initially in all of the animals. The apoA-I levels remained elevated in monkeys able to maintain their plasma cholesterol concentrations near basal levels (hyporesponders), but began to decrease in monkeys who became severely hypercholesterolemic (hyperresponders), reaching levels as low as 65-70% of their basal value by 24 weeks. The larger, lipid-rich HDL (HDL2) was shown by density gradient ultracentrifugation and gradient-PAGE (polyacrylamide gel electrophoresis) to be the HDL fraction responsible for these changes in apoA-I, completely accounting for the increase in apoA-I in hyporesponders and the decrease in apoA-I in hyperresponders. The HDL3 levels remained unchanged in hyporesponders but increased markedly in hyperresponders, partially compensating for the decrease of HDL2 in those animals. Gradient-PAGE showed the HDL3 to be heterogeneous, containing at least two populations of particles of the same density but differing significantly in size. The smaller of these HDL3 were most prominent in the HFHC-fed hyperresponders. These data show that nonhuman primate HDL is both physically and metabolically heterogeneous, and indicate that a high fat-high cholesterol diet-induced hypercholesterolemia severely depresses the HDL2 levels.     

Biotransformations Of Fluoroaromatic Compounds: Accumulation Of Hydroxylated Products From 3-Fluorophthalic Acid Using Mutant Strains Of Pseudomonas Testosteroni

Biotransformations of 3-fluorophthalic acid have been investigated using blocked mutants of Pseudomonas testosteroni that are defective in the metabolism of phthalic acid (benzene-1,2-dicar-boxyfic acid). Mutant strains were grown with L-glutamic acid in the presence of 3-fluorophthalic acid as inducer of phthalic acid catabolic enzymes. Products that accumulated in the medium were isolated, purified and identified as the fluoroanalogues of those produced from phthalic acid by the same strains. The previously undescribed fluorochemicals cis-3-fluoro-4,5-dihydro-4,5-dihydroxyphthalic acid (VI) and 3-fluoro-4,5-dihydroxyphthalic acid (VII) have been obtained by biotransformation of 3-fluorophthalic acid, and 3-fluoro-5-hydroxyphthalic acid (X) from (VI) by freeze drying. In addition, samples of 2-fluoro-3,4-dihydroxybenzoic acid (2-fluoroprotocatechuic acid, VIII) and 3-fluoro-4,Sdi-hydroxybenzoic acid (5-fluoroprotocatechuic acid, IX) were obtained with a mutant deficient in the ring-fission enzyme, showing that the fluorine substituent in their precursor substrate (VII) is not recognized by the decarboxylase of the pathway, which shows no preference for which carboxyl group is removed. These studies of 3-fluorophthalic acid catabolism demonstrate the opportunities available for the production of novel fluorochemicals in reasonable yields by microbial transformations.     

Temporal changes in effectiveness of an inspiratory inhibitory electrical pontine stimulus

We determined the temporal changes in effectiveness of inspiratory-shortening expiratory-prolonging stimulus trains delivered in the region of the nucleus parabrachialis medialis and compared the responses to those observed during trains delivered to the vagus in the same animals (pentobarbital, sodium-anesthetized paralyzed cats). The inspiratory inhibitory effect of the pontine stimulus was assessed from the effect the stimulus has on threshold for terminating inspiration. Stimulus effect increased gradually, reached a peak at 0.2-0.4 s, and declined thereafter. The time of occurrence of peak effect was different from that observed in the course of vagal stimulus trains. With long stimulus trains (19-40 s), the initial effect on inspiratory duration (TI) (i.e., shortening) rapidly subsided and, in six of eight animals, was replaced by TI prolongation. The initial effect on expiratory duration (TE) (i.e., prolongation) also gradually declined with time but TE remained above control throughout. The time constant of adaptation was very similar with vagal and pontine stimulus trains (12.2 and 11.0 s, respectively), but the gain of the adapting response was much more pronounced with pontine stimuli, resulting in a paradoxical effect while stimulation continued. We conclude that the response to pontine stimuli, as with vagal stimuli, displays both integrative and adaptive characteristics. The similarity of the time constants for vagal and pontine adaptation responses suggests that these two inputs share common processing pathways.