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One of the most economically-viable processes for the bioconversion of many types of lignocellulosic wastes is represented by edible mushroom cultivation. Lentinula edodes, Volvariella volvacea and Pleurotus sajor-caju are three important commercially cultivated mushrooms which exhibit varying abilities to utilise different lignocellulosics as growth substrate. Examination of the lignocellulolytic enzyme profiles of the three species show this diversity to be reflected in qualitative variations in the major enzymic determinants (i.e. cellulases, ligninases) required for substrate bioconversion. For example, L. edodes, which is cultivated on highly lignified substrates such as wood or sawdust, produces two extracellular enzymes which have been associated with lignin depolymerisation in other fungi, (manganese peroxidase and laccase). Conversely, V. volvacea, which prefers high cellulose-, low lignin-containing substrates produces a family of cellulolytic enzymes including at least five endoglucanases, five cellobiohydrolases and two β-glucosidases, but none of the recognised lignin-degrading enzymes.

Vanadate (10 microM ), a potent inhibitor of tyrosine phosphatase, added simultaneously potentiated the sodium butyrate (BuONa)-induced growth inhibition. Furthermore, at 1 mM BuONa alone, after 96 h of incubation, about 20 +/- 5% of cells exhibited the morphological characteristic of apoptosis, as established by nuclear changes (condensed and fragmented nuclei) and decrease in cell size. After treatment of cells with 1 mM BuONa in the presence of 10 microM vanadate, apoptotic cells became more abundant; 90 +/- 3% of cells presented morphological characteristics of apoptosis after 96 h of incubation. Flow cytometric measurement of DNA content demonstrated the accumulation of cells in G1 phase after 72 h of incubation with 1 mM BuONa alone. In the presence of vanadate (10 microM ), accumulation of cells in G1 phase appeared after shorter times of incubation (48 h) with BuONa. A substantial increase in the proportion of cells with degraded DNA characteristic of apoptosis was observed after 48- to 72-h incubation with BuONa in the presence of vanadate. BuONa-induced apoptosis was accompanied by the increase of tyrosine phosphorylation of cellular proteins pp37 and pp97. Our results raised the possibility that regulation of tyrosine phosphorylation of pp37 and pp97 is an important event that heralds the BuONa-induced apoptosis.

TML-1 and TML-2 were two lectins isolated from the mushroom Tricholoma mongolicum. They did not differ appreciably in their pH stability and cationic requirement for hemagglutinating activity. They both stimulated the production of nitrite ions and activated the macrophages in mice. The two lectins were able to inhibit the growth of implanted sarcoma 180 cells by 68.84% and 92.39% respectively. The growth of tumor cells in the mouse peritoneal cavity was also inhibited by the two lectins with TML-2 expressing a greater potency.

Two lectins, TML-1 and TML-2, were isolated from Tricholoma mongolicum by ion-exchange chromatography and gel filtration. They are dimers with molecular weight near 37000. The hemagglutinating activities of TML-1 and TML-2 are sensitive to lactose inhibition and are stable between 10 and 80 degrees C. They exhibit antiproliferative activities against mouse monocyte-macrophage PU5-1.8 cells and mouse mastocytoma P815 cells in vitro. The two lectins differ in the content of proline and tyrosine residues. Both are non-glycoproteins and have hydroxyproline residues.

The anti-tumour component (Fraction A) found in the culture filtrates of a local mushroom, Tricholoma sp. (strain STC20-T1), was purified using DEAE-cellulose ion exchange chromatography and Sepharose CL-4B gel filtration. Of its two purified sub-fractions, A-1 and A-2, only the latter showed anti-tumor activity. When Fraction A-2 was treated with cetyltrimethylammonium hydroxide and chloroform/butanol (24:1, v/v), it behaved as a proteinbound polysaccharide, with a molecular mass estimated to be 154 kDa by gel filtration. It contained 40% polysaccharide, which consisted of fucose, galactose, glucose, arabinose and mannose, and 30.5% protein, the amino-acid composition of which was determined. Fraction A-2 could inhibit the growth of Sarcoma-180 implanted in mice intraperitoneally and subcutaneously, with no sign of toxicity, at a dose of 20 mg/kg.day for 10 days.

Two irreversible inhibitors, iodoacetamide and diethylpyrocarbonate, were used to select intraspecific fusion products of two mushroom species, Coprinus cinereus and Schizophyllum commune. Iodoacetamide was the more suitable inhibitor because it gave a low breakage frequency and low survival rate of the cells in the inactivation experiments. Fusion-induced by polyethylene glycol and electro-fusion were compared and, under optimal conditions, gave fusion frequencies of 16.7% to 50.0% and 6.9% to 8.4%, respectively. All fusion progeny were heterokaryons (dikaryons) and had clamp connections. There were no differences in the morphology and fruiting ability of the fusion progeny and those of the heterokaryons generated from mating.

A polysaccharide-peptide complex (PSPC) with immunomodulatory and antitumor activities was obtained from a submerged mycelial culture of Tricholoma sp., a local edible mushroom. The polysaccharide-peptide complex exhibited a molecular weight of 17 K in gel filtration and a single band after SDS-polyacrylamide gel electrophoresis. It was characterized by non-adsorption on both DEAE-Sepharose CL-6B and CM-cellulose. It could activate the macrophages, stimulate the proliferation of T-cells, and inhibit the growth of sarcoma 180 in mice. It possessed more potent immunomodulatory and antitumor activities than Coriolus versicolor polysaccharopeptide (PSP) and deserves to be studied as a potential agent for immunomodulation and cancer therapy.

After regeneration of protoplasts of seven heterothallic of edible mushrooms, two types of monokaryons were recovered, being identified by the absence of clamp connections. In regenerated colonies, monokaryons grew more slowly than dikaryons and so could be distinguished from them. In all species, the yield of monokaryons in the regenerated colonies was over 45%. The mating types and auxotrophic markers were the same in the protoplasted monokaryons and parental monokaryons. In comparison with other monokaryotization methods, protoplasting is rapid, simple and effective; its applications in breeding of edible mushrooms are discussed.

Pleurotus sajor-caju was generally more tolerant to lignin-related phenolic monomers and tannin derivatives than Lentinus edodes and the straw mushroom, Volvariella volvacea. Several phenols, at up to 5 mM, enhanced mycelial growth of P. sajor-caju. No clear pattern was evident when the effects of phenols and tannins on the growth of V. volvacea and L. edodes were compared, but the lower concentrations of 4-hydroxybenzaldehyde and vanillin which were tested were markedly more toxic to the straw mushroom. The distribution of phenolic monomers and tannin derivatives in the agricultural wastes used for mushroom cultivation may be an important growth determinant. However, the differences in the growth inhibition profiles of L. edodes, P. sajor-caju and V. volvacea suggest that, alone, the effect of these compounds on fungal growth is unlikely to account for the varying abilities of the three mushroom species to grow and fruit on a particular lignocellulosic substrate.

The Regional Network for Microbiology in Southeast Asia is one of the programmes for regional cooperation in the basis sciences established by UNESCO in collaboration with the government of Japan through a funds-in-trust agreement, in 1974. Up to 1991, the network has organized 50 scientific activities and 945 young microbiologists have received training in microbiology. The nature of the programme's activities has become more specific recently and concerns microbial resources and use of biotechnology to conserve the environment.

Volvariella volvacea, the straw mushroom, has long been considered as a primary homothallic species. However, great variations in monosporous isolates have ralsed a considerable debate on the sexuality pattern of this edible Basidiomycete fungus. Because clamp connection is absent in V. volvacea, the production of genetically marked strains offers a possible means of resolving this problem. In this study, ultraviolet irradiation of basidiospores and mycellal fragments was used to induce crystal-violet- and malachite-green-resistant mutants. Cross-resistance to crystal violet and malachite green occurred between both classes of mutant. The difficulties of inducing mutants in this multinucleate fungus and the significance of mutant markers are discussed.

The McCarthy Screening Test, used to identify children with learning difficulties, yields a pass-fail decision for each subtest. The reliability of these decisions is studied using several criterion-referenced testing methods (N = 1,323). The several results are evaluated. It is suggested that dependability indices be adopted for clinical instruments such as the MST.

A comparative study of cefoperazone and amikacin in severe surgical infections was conducted with 60 patients equally allocated to two groups. The daily dosage of cefoperazone ranged from 2 to 4 gm in two equally divided doses, and the daily dosage of amikacin ranged from 900 to 1,000 mg in two equally divided doses. All patients were given antibiotics for five to ten days. With cefoperazone, there were satisfactory clinical responses in 83% (29/35) of the infections; with amikacin, 74% (23/31). Cefoperazone was more effective than amikacin in biliary tract infections. On bacteriological examination, 7.5% of the organisms isolated were resistant to cefoperazone and 10% to amikacin. In mixed infections, cefoperazone and amikacin had failure rates of 29% and 36%, respectively. Further trials are needed to define the role of cefoperazone in anaerobic and in mixed infections.

1. The antihypertensive and renal effects of cilazapril, a new angiotensin converting enzyme inhibitor, were evaluated in both two-kidney, one-clip Goldblatt hypertensive rats (n = 11) and normotensive rats (n = 6). 2. Intravenous infusion of cilazapril (1 mg/kg followed by 25 micrograms min-1 kg-1) caused significant reductions of blood pressure from 163 +/- 3 to 122 +/- 4 mmHg and from 157 +/- 2 to 113 +/- 3 mmHg in two separate groups of hypertensive rats and from 124 +/- 1 to 105 +/- 2 mmHg in normotensive rats. The hypotensive effect in terms of absolute value of percentage change was greater in hypertensive rats than in normotensive rats (41 +/- 6 vs 20 +/- 3 mmHg or 25 +/- 4% vs 16 +/- 2%, respectively). 3. Cilazapril increased glomerular filtration rate, urine flow, and absolute and fractional excretion rates of sodium and potassium in the non-clipped kidney of hypertensive rats. In contrast, the clipped kidney exhibited a depressed renal function during cilazapril infusion. 4. In normotensive rats, the hypotensive and enhanced renal function responses to cilazapril were much less than those of the non-clipped kidney of hypertensive rats. 5. Superimposed administration of either angiotensin II or angiotensin III during cilazapril infusion completely reversed the blood pressure and bilateral renal responses of cilazapril in both hypertensive and normotensive rats. 6. These results indicate that cilazapril reduces arterial pressure and enhances renal excretion mainly via inhibition of angiotensin II and angiotensin III formation.

An aqueous extract of Pleurotus sajor-caju was found to have a hypotensive effect in rats. Intravenous infusion of the extract into rats caused a decrease of the mean systemic blood pressure in a dose dependent manner. A typical dose of 25 mg of the extract decreased the mean systemic blood pressure from 110 mm Hg to 70 mm Hg. The systolic and diastolic pressure changed proportionally with minimal alteration in heart rate. The hypotensive effect of the extract was not due to its major electrolyte content because a solution reconstituted with the same electrolyte composition had a transient pressor effect rather than lowering the blood pressure. The same extract was also found to affect renal hemodynamics such that it caused a decrease in the glomerular filtration rate by more than 50% after 120 minutes. The effect did not seem to be mediated through changes in systemic blood pressure.

Clear cell sarcoma of the kidney (CCSK) is a highly malignant childhood tumor, distinguished from classic Wilms' tumor by its propensity to metastasize to the skeletal system. Authors described a case of CCSK from a 3-year-old boy in the right kidney, showing various histologic features, such as classic, epithelioid, trabecular, neurilemmoma-like, cystic and entrapped collecting tubular pattern. Ultrastructurally epithelial differentiation was absent. Immunohistochemically, none of the intrinsic tumor cells showed positive staining with the antibodies against the keratin, S-100 protein, carcinoembryonic antigen, vimentin, desmin and myoglobin, suggesting primitive mesenchymal cell in origin.

This study was conducted to evaluate the efficacy and safety of intravenous sulbactam/ampicillin followed by oral sultamicillin. Parenteral sulbactam/ampicillin was administered for 7 to 14 days to 152 in-patients with moderate to severe infections. All patients were treated with sulbactam/ampicillin, but only 140 patients received oral sultamicillin therapy. Eighty-nine men and 63 women participated in this study. Infections included intraabdominal (42 cases), respiratory tract (52 cases), skin and soft tissue (29 cases), urinary tract (16 cases), and miscellaneous infections (14 cases) that included typhoid fever, gastroenteritis, septicemia, and surgical wound infection. Six (4%) patients reported six study drug-related adverse experiences. Gastrointestinal side effects were most common and included epigastric burning and indigestion. Diarrhea was not reported and no patient discontinued drug therapy because of an adverse event. Laboratory abnormalities were infrequent and clinically insignificant. Overall, 98% of the 114 evaluable patients achieved clinical cure or improvement following treatment with sulbactam/ampicillin and sultamicillin. Cured or improved patients in each diagnostic group were 97% for intraabdominal infections, 100% for respiratory tract infections, 100% for skin and soft tissue infections, 100% for urinary tract infection, and 91% for other types of infections. Only 2 (2%) patients were judged to be treatment failures. Microbiologic efficacy, or eradication, was 86% overall, ranging from 75 to 100%. Persistence of pathogens occurred in 5%, and eradication with development of a superinfection occurred in 4%. Fifty-seven percent (30/50) of the isolates tested were resistant to ampicillin alone whereas only 21% (9/42) were resistant to sulbactam/ampicillin (p = 0.002).(ABSTRACT TRUNCATED AT 250 WORDS)