Use of garden organic compost in vegetable production under contrasting soil P status

Little research has been carried out on the agronomic value of compost produced from garden organics for vegetable production. A field experiment was established in Camden, near Sydney, Australia, to (i) evaluate the effect of the compost on vegetable production and soil quality relative to conventional practice, (ii) compare vegetable production under high and low soil P status, and (iii) monitor the changes in soil P concentration under two compost treatments relative to conventional farmers’ practice. After three successive crops (broccoli, eggplant and cabbage), results indicate that compost (120 dry t/ha) and half-compost (60 dry t/ha supplemented by inorganic fertilisers) treatments can produce similar yield to the conventional practice of using a mixture of poultry manure and inorganic fertiliser. Furthermore, similar yields were achieved for three different crops grown under high and low P soil conditions, clearly demonstrating that the high extractable soil P concentrations currently found in the vegetable farms of Sydney are not necessary for maintaining productivity. The compost treatments also significantly increased soil organic carbon and soil quality including soil structural stability, exchangeable cations, and soil biological properties. Importantly, the compost treatment was effective in reducing the rate of accumulation of extractable soil P compared with the conventional vegetable farming practice. Our results highlight the potential for using compost produced from source separated garden organics in reversing the trend of soil degradation observed under current vegetable production, without sacrificing yield.

A 15-kD interferon-induced protein and its 17-kD precursor: expression in Escherichia coli, purification, and characterization

Using recombinant DNA technology, a 15-kD interferon (IFN)-induced protein and its 17-kD precursor have been expressed in Escherichia coli to obtain sufficient quantities of each protein for the investigation of their biological roles. Both the 15-kD and 17-kD proteins have been purified to homogeneity and crystallized. The recombinant 15-kD protein has an identical reversed-phase HPLC elution profile to that of the native 15-kD protein purified from human cells. Furthermore, the recombinant 15-kD and 17-kD proteins have identical amino- and carboxy-terminal amino acid sequences to those predicted from the DNA sequence. The native and recombinant 15-kD proteins give identical tryptic peptide maps, and the recombinant 17-kD protein gives only one additional tryptic peptide. We conclude that the recombinant 17-kD and 15-kD proteins are identical to the 17-kD precursor and the 15-kD stable product synthesized in human cells in response to IFN stimulation. In addition, we have demonstrated that the recombinant 17-kD precursor protein can be converted to the 15-kD protein by cytoplasmic extracts of human cells.

Structure and differential mechanisms of regulation of expression of a serine esterase gene in activated human T lymphocytes

A cDNA clone encoding a polypeptide resembling proteolytic serine esterases (from cytotoxic T-cells; SECT) was isolated from human peripheral blood lymphocytes which had been cultured in the presence of the T-cell mitogen phytohemagglutinin for 72 h. The cDNA encodes a polypeptide of 247 amino acids which show homology of 99% with the protein sequence encoded by a cDNA clone (1-3E) isolated from staphylococcal enterotoxin A-stimulated human peripheral blood lymphocytes and 68% with the protein sequence (cytotoxic cell protease type I) derived from a cDNA clone (C11) encoding a serine esterase isolated from a murine cytotoxic T-cell line. The overall nucleotide sequence homology between the SECT cDNA and 1-3E was 99% and 73% between SECT and C11. Comparing the coding regions of SECT and C11 showed 75% homology, whereas the 5'- and 3'-untranslated regions showed 67% homology. Phytohemagglutinin stimulation results in 30-, 60-, and 370-fold increases in cytoplasmic SECT mRNA with respect to unstimulated cells after 6-, 24-, and 72-h cultures, respectively. At 6 h, the increase in SECT mRNA occurs in the absence of increases in SECT gene transcription and cytoplasmic mRNA stabilization. A 5-fold increase in SECT nuclear RNA seen at this time suggests that stabilization of SECT nuclear RNA transcript is responsible for early increases in SECT mRNA levels. At 24 and 72 h, the increased cytoplasmic SECT mRNA levels can be accounted for by increased transcriptional activity of the SECT gene.

A 15-kDa interferon-induced protein is derived by COOH-terminal processing of a 17-kDa precursor

An interferon-induced 15-kDa protein is synthesized from a precursor of higher molecular weight; the precursor contains 165 amino acids (17 kDa), whereas the stable product (15 kDa) contains 156 amino acids. The stable 15-kDa form is derived from the precursor 17-kDa form by the removal of eight amino acids from the COOH terminus and the methionine from the NH2 terminus. The existence of the precursor 17-kDa protein can be demonstrated after brief periods of in vivo labeling with [35S]methionine and by translation of mRNA in vitro.

Interferon-induced transcription of a gene encoding a 15-kDa protein depends on an upstream enhancer element

A human gene encoding an interferon-induced 15-kDa protein has been isolated from a genomic library. The gene appears to be single-copy and is composed of two exons, the first of which contains the ATG translation initiation codon. In vitro nuclear run-on assays showed that the transcription rate of the gene is stimulated after interferon treatment. To analyze transcriptional regulatory sequences, we constructed recombinant plasmids for use in transient transfection assays of HeLa cells. Constructs containing 115 nucleotides 5' to the transcription initiation site were found to be fully inducible by interferon. Assays of deletion mutants identified a critical element for interferon induction located between -115 and -96, just upstream of the "CCAAT box." Moreover, a DNA fragment including this region can confer interferon inducibility on a heterologous promoter (thymidine kinase) when cloned in either orientation upstream of the gene or downstream of the gene. These are properties characteristic of an enhancer element that is active only after treatment with interferon. This regulatory sequence may be shared by a group of interferon-induced genes, since a very similar sequence is present within the functional region near the RNA start site of another interferon-induced gene.

A growth inhibitory protein secreted by human diploid fibroblasts. Partial purification and characterization

We have identified and partially purified a growth inhibitor protein secreted by human diploid fibroblast cells. This protein is not secreted constitutively but only after induction with the double stranded hetero duplex polyriboinosinic:polyribocytidylic acid. The growth inhibitory activity has been purified 3,800-fold and has an estimated molecular mass of 12,000 daltons. The protein will inhibit the growth in culture of human diploid fibroblast cells, human cells derived from tumors, and mouse L cells. Although interferon-beta is secreted with the growth inhibitory protein, the partially purified growth inhibitory protein has no antiviral activity, and its activity is not neutralized by antibodies to interferon-alpha, interferon-beta, and interferon-gamma. We believe this growth inhibitory activity to reside in a newly defined protein and have named it fibroblast-derived growth inhibitor.

Molecular characterization of the interferon-induced 15-kDa protein. Molecular cloning and nucleotide and amino acid sequence

We have isolated a cDNA clone for an interferon-induced 15-kDa protein. The cDNA clone was prepared from mRNA isolated from interferon-beta-treated human Daudi cells. The clone of 635 base pairs contains an open reading frame coding for a protein of 145 amino acids, and suggests for the mRNA a 75-base pair 5' untranslated and a 125-base pair 3' untranslated region. Approximately 85% of the amino acid sequence of the 15-kDa protein has been independently obtained from 2 nmol of material using microsequencing technology on the N terminus of the intact protein and on tryptic and chymotryptic peptides. The amino acid sequence of the isolated protein is identical to the amino acid sequence deduced from the cDNA. Northern blot analysis confirmed that the mRNA for the 15-kDa protein is undetectable in untreated cells, but is greatly induced following interferon treatment.

Interferon regulates c-myc gene expression in Daudi cells at the post-transcriptional level

c-myc gene mRNA is reduced by greater than 75% in the human lymphoblastoid cell line Daudi when growth is inhibited by treatment with human interferon beta (IFN-beta). In the present communication, we describe the effect of IFN-beta treatment on transcription of the c-myc gene and on the steady-state level of c-myc mRNA in the cytoplasm of Daudi cells. The results show that, although the rate of c-myc transcription is not significantly different in nuclei isolated either from untreated cells or from those treated with IFN-beta for 3 or 24 hr, the level of c-myc mRNA in the cytoplasm is reduced by 60% within 3 hr of IFN-beta treatment. These results suggest that IFN-beta regulates the c-myc mRNA at a post-transcriptional level. These results are in contrast to the regulation of two IFN-beta-induced genes that under identical conditions are regulated in these cells at the transcriptional level. We have also detected induction of the (2'-5')oligoadenylate synthetase (2-5A synthetase) gene in IFN-beta-treated Daudi cells. Since certain c-myc transcripts have the capacity to form double-stranded RNA regions, we propose that one mechanism by which c-myc could be regulated post-transcriptionally in IFN-beta-treated cells is by activating, through its own double-strandedness, the 2-5A synthetase/RNase L endonuclease system, which would cause selective degradation of the c-myc RNA.

Interferon-beta enhances the synthesis of a 20,000-dalton membrane protein: a correlation with the cessation of cell growth

Interferons (IFNs)-alpha and -beta but not -gamma enhance the synthesis of a protein in the membranes of Daudi cells. This protein has an estimated molecular weight of 20,000 (20 kD). Furthermore, the 20-kD protein is enhanced only in the membranes of cells whose growth can be inhibited by IFN-beta (Daudi, WISH, HL-60, diploid fibroblasts) but not in the membranes of cells whose growth is not inhibited by IFN-beta (Namalva, Raji). These data suggest a correlation between the IFN-beta-enhanced 20-kD membrane protein and the inhibition of cell growth by IFN-beta.

One-carbon metabolism in lectin-activated human lymphocytes

Serine is an essential amino acid for the lectin-mediated transformation of human peripheral blood lymphocytes due to the inability of this cell to synthesize sufficient quantities via either the phosphorylated pathway or by reversal of the serine hydroxymethyltransferase reaction to meet the metabolic demands. The level of intracellular serine is tightly regulated, and the culture medium concentration for optimum cellular transformation falls within a relatively narrow range. The three-carbon atom of serine is the major source of one-carbon units required for purine and pyrimidine nucleotide biosynthesis, but the key effect of both serine deprivation and of high medium serine levels would appear to be on protein synthesis. Although an alternative source of one-carbon units, as provided by high levels of formate in the culture medium, can partially reverse the effects of serine deprivation, the only other demonstrable source of one-carbon units, tryptophan, requires serine for its incorporation and subsequent metabolism. Methionine is also essential for lymphocyte transformation and is involved in the synthesis of a small amount of phosphatidylcholine, although most of this phospholipid is provided by choline and lysophosphatidylcholine from the serum-supplemented culture medium.

Changes in levels of actin and tubulin mRNAs upon the lectin activation of lymphocytes

The expression of beta-actin, gamma-actin, alpha-tubulin, and beta-tubulin mRNA during the lectin activation of human peripheral blood lymphocytes was examined with specific cDNA clones. The resting lymphocyte has a low level of both alpha- and beta-tubulin mRNAs, and these increase 10-fold after 72 h of lectin stimulation in which maximum cell transformation is achieved. Although there is a slight increase in tubulin mRNA during the first 6 h, most of the increase occurs between 6 and 24 h as the cells start to increase their RNA content and progress from G0 into G1. Both beta- and gamma-actin mRNAs are more abundant than the tubulin mRNAs in resting cells, with beta-actin mRNA being the major species. Upon activation, beta-actin mRNA increases threefold, whereas gamma-actin mRNA increases almost sixfold. Both beta- and gamma-actin mRNA are elevated 2.5-fold as early as 6 h, the gamma-actin mRNA level then increasing more than beta-actin between 6 and 24 h, resulting in the reduced beta-actin/gamma-actin mRNA ratio. The lectin-stimulated lymphocyte has a similar beta-actin/gamma-actin mRNA ratio as that of the human leukemic T-lymphoblast cell line CCRF-CEM. These increases are over and above the general increase in polyadenylated RNA content upon lectin activation. On returning to a noncycling state, the levels of these cytoskeletal mRNAs decrease. There were two beta-tubulin mRNAs present in lymphocyte cytoplasm, one of 1.8 kilobases and one of 2.8 kilobases in length. The nongrowing lymphocytes had relatively lower levels of the larger sized mRNA. Upon stimulation, the relative level of the larger mRNA was increased, and at 72 h the cells had approximately equal levels of both mRNAs as did the leukemic lymphoblasts.

Terminal incorporation of 2'-deoxyadenosine into polyadenylate segments of polyadenylated RNA in G1-phase-arrested human T-lymphoblasts

In the presence of the adenosine deaminase inhibitor erythro-9-[3(2-hydroxynonyl)]adenine microM concentrations of 2'-deoxyadenosine (dAdo) are toxic to nondividing human lymphoid cells and induce G1-phase arrest in T-leukemic lymphoblasts, effects which appear to be independent of ribonucleotide reductase inhibition by accumulated 2'-deoxyadenosine 5'-triphosphate. We sought to determine if 2'-deoxyadenosine 5'-triphosphate had effects similar to those of other cytotoxic adenosine analogues which are incorporated into polyadenylated RNA [poly(A)+ RNA]. In the presence of erythro-9-[3-(2-hydroxynonyl)]adenine, 8-14C]dAdo, at minimal cytostatic concentrations, was incorporated into the polyadenylate segments of cytoplasmic poly(A)+ RNA in the human T-leukemic lymphoblast line CCRF-CEM, and 70% of incorporated dAdo was in the 3'-terminal position. No DAdo was found in enzyme hydrolysates of nonpolyadenylated regions of poly(A)+ RNA or of poly(A)-RNA. Enzymic hydrolysis of polyadenylated segments from labeled poly(A)+ RNA yielded adenosine:dAdo ratios of approximately 55:1.

De novo purine synthesis in human lymphocytes. Partial co-purification of the enzymes and some properties of the pathway

A partially purified enzyme extract from lectin-transformed human peripheral blood lymphocytes synthesized purine nucleotides de novo. Although the relatively lower specific activity of the pathway compared with that in the avian liver preparation previously described (Rowe, P. B., McCairns, E., Madsen, G., Sauer, D., and Elliott, H. (1978) J. Biol. Chem. 253, 7711-7721) limited the extent of purification, a number of properties were established: (i) Ammonia could be utilized as readily as glutamine for the synthesis of phosphoribosylamine but only glutamine provided N-3 of the purine ring; (ii) in the presence of either GTP or NAD, AMP or GMP were synthesized; (iii) purine synthesis was inhibited at the level of phosphoribosylamine synthesis by both AMP and GMP, irrespective of whether ammonia or glutamine was the N donor; (iv) while the synthesis of AMP and GMP from IMP was self-regulated, GTP also appeared to be an inhibitor of the synthesis of GMP from IMP; (v) amidophosphoribosyltransferase was isolated from both transformed and nontransformed cells in a low molecular weight form which was converted to a high molecular weight form in the presence of GMP; and (vi) no evidence was obtained for the existence of a classical multienzyme complex for purine synthesis.

The effects of lectin transformation on cytoplasmic polyadenylated RNA from human lymphocytes

The translational activity of cytoplasmic poly(A)+ RNA from resting human lymphocytes was approximately 20% of that from phytohemagglutinin-transformed lymphocytes in a rabbit reticulocyte lysate assay. Translation assays in the presence of cap analogues suggested that the mRNA from resting cells was relatively deficient in functional 5'-terminal cap structures. Neither mRNA fraction inhibited the translation of globin mRNA in the cell-free assay, and both preparations were essentially pure as shown by hybridisation with [3H]poly(U). The size distribution and poly(A) tail length of poly(A)+ RNA was similar in the resting and transformed cell and both preparations directed the synthesis of peptides of molecular weight 15 000 to 90 000. Two dimensional gels of total proteins from resting and transformed lymphocytes showed predominantly quantitative changes. However cross-hydridising cDNA and mRNA from resting and transformed cells after the common sequences have been removed by hydroxylapatite chromatography showed that about 4% of the cytoplasmic poly(A)+ RNA from transformed lymphocytes was not present in resting cells. This difference may result from transformation-specific gene expression.

Human interferon-beta: effects of deglycosylation

Human fibroblast-derived interferon-beta (IFN-beta) labeled in vivo with 35S-methionine and purified to greater than 90% radiochemical purity has been used to study the effect of glycosidases on its biological activity and its molecular weight. Incubation of the radioactive interferon with the glycosidases causes a reduction in the estimated molecular weight from 23,000 to 18,000 as determined by electrophoresis on SDS-gels. There are intermediate transient sizes that are generated prior to 18,000, but not proteins are observed that are smaller than 18,000 even after prolonged incubation. The deglycosylated IFN-beta (18,000) induces the antiviral state in cells in culture and inhibits the growth of cells in culture. We conclude that the carbohydrate of IFN-beta is not essential for its biological activity on cells in culture.

Human fibroblast interferon. An improved purification

Human fibroblast interferon has been purified 2,900-fold to homogeneity. The purification is achieved in two steps by chromatography on blue Sepharose. The specific activity of the homogeneous interferon is 5 X 10(8) units/mg and the yield of biological activity has ranged from 20-40%. The interferon can exist as a monomer (Mr = 20,000) and as a dimer (Mr - 40,000). The dimer can be converted to the monomer by heating in sodium dodecyl sulfate and thioglycolic acid.

Otogenic pneumocephalus secondary to chronic otitis media

Spontaneous pneumocephalus is currently a rare manifestation of chronic otitis media. Although a rarity, the diagnosis must be considered when a patient has neurologic complaints and chronic otitis media. Despite the importance of early recognition and treatment in preventing potentially fatal complications, it has been noticeably neglected in recent otolaryngologic literature. We report a case, review the literature, and discuss the related pathophysiology. This case demonstrates the need for at least skull roentgenograms in patients with positive neurologic history and chronic otitis media and the danger of neglecting the proper treatment of cholesteatoma.

Lingual thyroid. Case report and review of the literature

We review the world literature on lingual thyroid. One of our cases of lingual thyroid is added to this body of information specifically because of the patient's unusual lack of any response to hormonal suppression treatment. This behavior was suggestive of a malignant neoplasm and was, in our opinion, indication for excisional biopsy, even without any of the usual symptoms associated with lingual thyroid. To our knowledge, this behavior has not been previously reported.