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H E Jones

Publications and source records attributed to H E Jones.

At least 19 recordsLinked to original sources
PubMed1992

The action of the putative neurotransmitters N-acetylaspartylglutamate and L-homocysteate in cat dorsal lateral geniculate nucleus.

1. We have examined the actions and pharmacology of two putative optic nerve transmitters, N-acetylaspartylglutamate (NAAG) and L-homocysteic acid (L-HCA), in the feline dorsal lateral geniculate nucleus (dLGN). We compared the responses obtained to iontophoretic application of these substances with those elicited by visual stimulation and application of specific N-methyl-D-aspartate (NMDA) and non-NMDA receptor agonists. The relative effects of the selective NMDA antagonist 3-[(+/-)-2-carboxypiperazin-4-yl]-propyl-1-phosphonic acid (CPP) and the selective non-NMDA antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) were tested on these responses. 2. There was a pronounced contrast between the influence of iontophoretically applied NAAG and L-HCA on dLGN cells. Iontophoretic application of NAAG [ejection current range 75-200 nA (mean 125 nA)] evoked either no effect (17/37), or very weak and sluggish excitatory (16/37) or inhibitory (4/37) effects. Conversely, L-HCA application [current range 25-136 nA (mean 67 nA)] elicited brisk and powerful excitatory responses (32/32) that were comparable with those produced by visual stimulation and iontophoresis of NMDA, kainate, and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA). 3. Responses to L-HCA were selectively antagonized by application of the NMDA receptor antagonist CPP but were generally much less affected by the non-NMDA receptor antagonist CNQX. The weak and inconsistent responses to NAAG were not compatible with an evaluation of antagonist effects. 4. CPP application at dose levels selective for NMDA with respect to kainate and AMPA did not exert equal effects on L-HCA and NMDA. Whereas the mean responses to L-HCA were reduced to 32% of control for Y cells and 21% for X cells, those to NMDA were 11 and 11%, respectively. However, the level of reduction of the visual response for X and Y cells was very similar to that of L-HCA, visual responses being reduced to 35 and 22% of control for Y and X cells. 5. CNQX application reduced the visual response level of Y cells to 64% of control and that of X cells to 65%. The mean level for the L-HCA response of Y cells was 106% of control; the mean for X cells, 79%, was substantially below control. The responses to kainate and AMPA were reduced to a much greater extent. 6. The data suggest that it is unlikely that NAAG is the optic nerve transmitter.(ABSTRACT TRUNCATED AT 400 WORDS)

6-Cyano-7-nitroquinoxaline-2,3-dione↗
PubMed1979

Isolation and characterization of a rubredoxin and two ferredoxins from Desulfovibrio africanus.

Rubredoxin and two distinct ferredoxins have been purified from Desulfovibrio africanus. The rubredoxin has a molecular weight of 6000 while the ferredoxins appear to be dimers of identical subunits of approximately 6000 to 7000 molecular weight. Rubredoxin contains one iron atom, no acid-labile sulfide and four cysteine residues per molecule. Its absorbance ratio A278/A490 is 2.23 and its amino acid composition is characterized by the absence of leucine and a preponderance of acidic amino acids. The two ferredoxins, designated I and II, are readily separated on DEAE-cellulose. The amino acid compositions of ferredoxins I and II show them to be different protein species; the greater number of acidic amino acid residues in ferredoxin I than in ferredoxin II appears to account for separation based on electronic charge. Both ferredoxins contain four iron atoms, four acid-labile residues per molecule. Spectra of the two ferredoxins differ from those of ferredoxins of other Desulfovibrio species by exhibiting a pronounced absorption peak at 283 nm consistent with an unusual high content of aromatic residues. The A385/A283 absorbance ratio of ferredoxins I and II are 0.56 and 0.62, respectively. The N-terminal sequencing data of the two ferredoxins clearly indicate that ferredoxins I and II are different protein species. However, the two proteins exhibit a high degree of homology.

Amino Acid Sequence↗
PubMed1979

Suppression of histamine-induced pruritus by hydroxyzine and various neuroleptics.

This study evaluates the ability of hydroxyzine and various neuroleptics to suppress histamine-induced pruritus in ten volunteer subjects with the use of a double-blind crossover protocol. The itch threshold was determined in each volunteer by intradermal injection of gradually increasing concentrations of histamine. Volunteers were then given the study drugs and placebo at the same interval of time, under near identical conditions, and the itch threshold was determined. Thiothixene, hydroxyzine hydrochloride, chlorpromazine, thioridazine, and a lactose placebo were evaluated. Compared to other drugs, hydroxyzine alone was more effective in the suppression of histamine-induced itch. Consequently, hydrozyzine may be more effective in histamine-induced pruritus. The neuroleptic drugs used in this study do not significantly suppress histamine-induced pruritus, but they may be beneficial in nonhistamine-induced pruritus or psychogenic pruritus.

Adult↗
PubMed1979

Filamentous fungal growth assay: correlation between [U-14C] glucose uptake and dry weight determinations.

The filamentous fungus Trichophyton mentagrophytes was grown in [U-14C] glucose supplemented nutrient broth. Growth was monitored in 200 microliter microcultures and 5 ml macrocultures by measuring the incorporation of 14C into trichloroacetic acid-insoluble macromolecules and in macrocultures by dry weight determination. Adjustment of the specific activity of the [U-14C] glucose medium supplement from 1080 muCi/mmole to 108 muCi/mmole decreased the rate of isotope uptake and prolonged availability so that growth beyond 36 h could be monitored radiometrically. The dry mycelial weight of the fungus was directly proportional (r = 0.995) to the amount of isotope incorporated. Isotope uptake in microcultures and macrocultures was kinetically identical. These data clearly indicate that the uptake of 14C by T. mentagrophytes can be used to monitor fungal growth accurately in both macrocultures and microcultures.

Carbon Radioisotopes↗
PubMed1979

Irritant and allergic reactions to topically applied Micatin cream.

Miconazole nitrate (Micatin cream) is a potent antifungal agent. Few side effects have been reported with topical application. We report on 10 patients who exhibited an intolerance to topical use of this drug. Most of the reactions were irritant in nature but in two instances, an allergic contact dermatitis was observed. Patch tests were positive to the cream base.

Dermatitis, Atopic↗
PubMed1979

North American blastomycosis: a review.

North American blastomycosis, first reported in 1894, and once thought to be a geographically localized disease, has now been reported worldwide. The greatest number of cases occur in the Mississippi, Missouri, and Ohio River basins. The organism enters the body via the lungs with subsequent dissemination to other organs, including the skin, eyes, bones, and genitourinary system. Patients most often present with cutaneous or pulmonary complaints. Demonstration of characteristic fungal morphology in microscopic smears or in histologic specimens is highly suggestive of Blastomyces dermatitidis. However, proof of the diagnosis is obtained only by mycologic culture. Some progress has been made using other laboratory methods to produce a rapid diagnosis. This paper reviews in detail the varied clinical presentations of blastomycosis, the laboratory diagnosis, and current treatment.

Amphotericin B↗
PubMed1979

Intravenous miconazole therapy of mycotic infections.

The efficacy and safety of intravenously administered miconazole nitrate was examined in eight patients with the following infections: cutaneous North American blastomycosis (one), extensive dermatophytosis(one), and chronic mucocutaneous candidiasis (six). Mycologic assessment included direct examination for fungal elements, fungal culture, and histopathology. Laboratory evaluations were performed before and at regular intervals during the study. The total miconazole nitrate dosage, which was administered over a seven- to 32-day period, ranged from 4.0 to 46.8 g. Follow-up examinations extended from two to 15 months. Excellent results were obtained in five patients and fair results in three. No renal, cardiac, hepatic, or hematopoietic toxicity was observed. Other side effects, however, necessitated premature cessation of therapy in four patients. Overall, intravenously administered miconazole is an effective antifungal agent for these cutaneous infections.

Adolescent↗
PubMed1978

Familial male pseudohermaphroditism with normal Leydig cell function at puberty.

Four male pseudohermaphrodites from two families have been described. Although reared as females, at puberty, the timing, pattern, and degree of masculinization was similar to that of a normal male. No feminization occurred. They had normal testicular testosterone synthesis as judged by plasma testosterone, LH and FSH concentrations, as well as incubations of testicular minces with labeled precursors. Studies on cultured skin fibroblasts indicated adequate peripheral 5 alpha-reductase and normal receptor affinity and capacity for dihydrotestosterone. The histology of the testis was suggestive of a primary testicular defect. A mosaic pattern was seen: some areas contained tubules with active spermiogenesis; other areas, only Sertoli cells. These male pseudohermaphrodites appear to have a defect in fetal testicular maturation in which inadequate fetal testosterone synthesis and defective differentiation of germinal elements occurred.

Adolescent↗
PubMed1978

Atopic dermatitis, impaired cellular immunity, and molluscum contagiosum.

A substantial elevation in the level of serum IgE (7,000 to 19,000 ng/ml) was noted in a man with atopic dermatitis and chronic molluscum contagiosum. Cell-mediated immunity (CMI) was depressed in vivo (cutaneous anergy), whereas in vitro tests showed normal numbers of "T" rosette-forming lymphocytes, a normal phytohemagglutinin-P-elicited lymphocyte transformation response, and lymphocyte transformation reactivity to the antigens streptokinase-streptodornase and purified protein derivative. Accumulated evidence suggests that patients with atopic dermatitis may have, associated with an elevated serum IgE level, a functional defect(s) in CMI that is greater in vivo than in vitro. This functional defect may impair host defense and account for the chronic molluscum contagiosum infection present in this patient.

Adult↗
PubMed1978

Skin changes and diseases associated with pregnancy.

During the gestational period, the skin is among the many organs undergoing changes. Various endocrine changes occurring in pregnancy are thought to give rise to certain skin changes such as pigmentary alterations, abnormalities in hair growth, vascular anomalies, and striae. Also, there are several skin diseases unique to the pregnant woman. Whereas the physiologic skin changes are mainly of cosmetic importance, the various pregnancy-unique skin diseases have associated symptoms, and an increase in both fetal and/or maternal morbidity and mortality is associated with several of these skin diseases.

Dermatitis↗
PubMed1977

Urticaria. An updated review.

Urticaria can result from many different stimuli, and numerous factors, both immunologic and nonimmunologic, are involved in its pathogenesis. Most commonly considered of immunologic mechanisms is the type I hypersensitivity state mediated by IgE. Another immunologic mechanism involves the activation of the complement cascade, which produces anaphylatoxins that can release histamine. Immunologic, nonimmunologic, genetic, and modulating factors converge on mast cells and basophils to release mediators capable of producing urticarial lesions. In addition to the clinical and laboratory diagnosis and treatment regimens, we review such mediators as histamine, kinins, serotonin, slow-reacting substance of anaphylaxis, prostaglandins, acetylcholine, fibrin degradation products, and anaphylatoxins that increase vascular permeability and can thereby produce wheals. Special consideration is given to histamine and the factors that regulate is secretory release from mast cells and basophils, including the modulating role of intracellular levels of cyclic adenosine monophosphate.

Bites and Stings↗
PubMed1977

The taxonomy of some new isolates of dissimilatory sulfate-reducing bacteria.

The interrelationships between 92 isolates of sporing and non-sporing sulfate-reducing bacteria were determined. Of the 116 biochemical and physiological characteristics examined, only 25 were useful for discrimination of groups. Responses to most of the test were negative. A similarity coefficient and a principal component factor analysis of these data were made. The deoxyribonucleic acids buoyant densities (DNA) from all strains and the electrophoretic properties of adenylylsulfotransferase (ATP-sulfurylase), adenylphosphosulfate (APS)-reductase, and sulfite reductase of selected isolated were determined. On the basis of these various data eight groups were recognized. Isolated of seven of these groups appeared to be similar to one or more named strains. Isolates of group E(DNA buoyant density, 1.708) were different from previously named strains. Sporins strains were not isolated from the Papua New Guinea location. Halophilic and non-halotolerant strains were isolated from highly saline locations in Australia. Results pertinent to the taxonomy and ecology of the sulfate-reducing bacteria are discussed.

Bacillaceae↗
PubMed1977

Dithionite reduction in the presence of a tetrapyrrole-containing fraction from the desulfoviridin of Desulfovibrio gigas.

Low-molecular-weight fractions obtained from the desulfoviridin of D. gigas and from the growth medium of Desulfovibrio sp. 10455 promoted the reduction of sodium dithionite to sulphide in the presence of reduced methylviologen. These fractions contained a tetrapyrrole of the isobacteriochlorin type which was not complexed with iron, nor was it complexed with protein. The observations are discussed in relation to the function of sulphite reductases in the sulphate-reducing bacteria.

Culture Media↗
PubMed1976

Metal accumulation by bacteria with particular reference to dissimilatory sulphate-reducing bacteria.

Dissimilatory sulphate-reducing bacteria, genera Desulfovibrio and Desulfotomaculum, exhibit a superior ability, over assimilatory organisms, to extract three amounts of metals from culture media. This property does not appear to be solely a function of the presence of H2S. In media containing elevated amounts of Fe, electron dense particles, provisionally identified as FeS, are deposited within the cells of dissimilatory bacteria.

Bacillaceae↗
PubMed1976

Variations in the spectrum of desulfoviridin from Desulfovibrio gigas.

Desulfoviridin preparations from D. gigas showed variations in the position of the absorption maximum the beta-peak) in the 580-nm region of the specturm. On treatment with Na2S2O4 a preparation with a beta-peak at 585 nm was affected rapidly, the 585-nm peak shifting to the 596-nm region; this was partially reversed by K3Fe(CN)6. Treatment of the original preparation with K3Fe(CN)6 resulted in a shift of the beta-peak to 582-583 nm. Desulfoviridins with beta-peaks from 580 to 583 nm were not rapidly affected by Na2S2O4. The spectrum of the chromophore of desulfoviridin way also affected by Na2S2O4 with the peak at 587 nm shifting to 597 nm; this effect was completely reversed by oxygen. There was no evidence to show that spectral variations in desulfoviridin preparations were due to the loss or acquisition of metal ions during growth or to the selection of mutants containing spectrally different desulfoviridins. It is suggested that during biosynethesis oal detachment of the chromophore, thus causing a change towards the spectral properites of the detached chromophore.

Desulfovibrio↗
PubMed1976

An automated radiometric microassay of fungal growth: quantitation of growth of T. mentagrophytes.

An automated radiometric microassay of the growth of Trichophyton mentagrophytes and other filamentous fungi is described. The assay is based upon the incorporation of 14C(U) glucose into the organism. Fractionation studies indicate that 73% of the label is found in trichloroacetic acid-insoluble macromolecular components of the mycelium. Incorporation of label directly correlated with growth as estimated by visual scoring of turbidity and as recorded in photomicrographs. Incorporation of 14C(U) glucose delineated a lag, exponential and stationary or plateau phase of growth. These phases could be completely inhibited by the antifungal agent tolnaftate. It was concluded that the growth of filamentous fungi can be successfully monitored by the radiometric method described. Moreover, this method is sensitive, accurate, reproducible, rapid and free of the variability inherent in many traditional estimates growth.

Radiometry↗