Functioning survival rate of fixtures and superstructures of osseointegrated implants: ten years of progress in Tokyo Dental College Hospital (second report)

Endoglucanase production was measured in culture filtrates of four species of Saccobolus growing in media containing glucose or crystalline cellulose as the only carbon sources. Enzyme activity was four to seven times higher in the presence of cellulose than glucose. S. saccoboloides showed maximal growth and enzyme production. The extracellular proteins secreted during growth on cellulose were separated by polyacrylamide gel electrophoresis and stained for proteins. A zymogram technique was used to visualize bands with endoglucanase activity. The four species showed different protein and isoenzyme patterns.     

Neonatal exposure to bFGF exerts NGF-like effects on mouse behavioral development

Metabolic products secreted by the fungal mycelia of Hirsutella thompsonii var. thompsonii (CBS 556.77D) in a defined culture broth in shake culture were tested for toxicity to Galleria mellonella larvae and Drosophila melanogaster adults via injection and per os application, respectively. In addition, the toxic effect of broth filtrate was observed in vitro in a cell line of Bombyx mori. Czapek-Dox broth fortified with 1% yeast extract stimulated more rapid mycelial growth and correspondingly more toxin production in time. At 25-30 degrees C, metabolic toxin(s) was detected in broth via bioassay at about 4-5 days postinoculation when mycelial biomass reached 5 mg/ml (dry wt). At these temperatures, biological activity of the filtrate peaked at about 8-10 days when mycelial growth reached a maximum (10 mg/ml, dry wt). This suggests a positive relationship between toxic metabolite and mycelial production. After 10 days, the toxicity of the filtrate appeared to decline gradually. Pathogenicity symptoms of the metabolites developed slowly in both G. mellonella and D. melanogaster. Early signs of lethargy appeared at 4 days postinjection and cumulative mortality of G. mellonella larvae was low after 1 week; however, the percentage of mortality reached 98-100% after 14 days. At death, G. mellonella larvae displayed small dark spots on a brownish cuticle. Histopathological effects were observed in the larval midgut, malpighian tubules, hypodermis, fat body, hemocytes, muscle, and silk glands. Cellular change consisted of pycnosis of the nucleus and a reduction in cytoplasm density. Highest mortality (78.8%) to adult D. melanogaster occurred after 10 days post-treatment.(ABSTRACT TRUNCATED AT 250 WORDS)     

Rapid atrazine mineralisation in soil slurry and moist soil by inoculation of an atrazine-degrading Pseudomonas sp. strain

The evaluation of pesticide-mineralising microorganisms to clean-up contaminated soils was studied with the widely applied and easily detectable compound atrazine, which is rapidly mineralised by several microorganisms including the Pseudomonas sp. strain Yaya 6. The rate of atrazine removal was proportional to the water content of the soil and the amount of bacteria added to the soil. In soil slurry, 6 mg atrazine kg soil-1 was eliminated within 1 day after application of 0.3 g dry weight inoculant biomass kg soil-1 and within 5 days when 0.003 g kg soil-1 was used. In partially saturated soil (60% of the maximal water-holding capacity) 15 mg atrazine kg soil-1 was used. In unsaturated soil, about 60% [U-ring-14C] atrazine was converted to 14CO2 within 14 days. Atrazine was very efficiently removed by the inoculant biomass, not only in soil that was freshly contaminated but also in soil aged with atrazine for up to 260 days. The bacteria exposed to atrazine in unsaturated sterile soil were still active after starvation period of 240 days: 15 mg newly added atrazine kg soil-1 was eliminated within 5 days.     

Skeletal muscle ventricles: frontiers in 1995

In different time after application of 12.5 microM colchicine-inhibitor of exoplasmic current to the ischiadicus the quantity of amino acid residues of methionine and cysteine in the sarcoplasmic reticulum decreases, its protein content changes. The Ca(2+)-ATPase activity increases on the 3d day after colchicine application and decreases on the 14th day. Analogical changes are observed in the capacity of the sarcoplasmic reticulum to transport calcium ions, the Michaelis constant in this case being stable. Passive outflow of Ca2+ from the sarcoplasmic reticulum vesicules changes in such a way: the Michaelis constant decreases with a simultaneous increase in the maximal velocity after 14 and 28 days of colchicine application.     

Time-dependent changes of serum carboxy-terminal peptide of type I procollagen and carboxy-terminal telopeptide of type I collagen concentrations in patients with acute myocardial infarction after successful reperfusion: correlation with left ventricular volume indices

To test the hypothesis that in patients with acute myocardial infarction (AMI), changes in the concentrations of the serum carboxy-terminal peptide of type I procollagen (PICP) and the carboxy-terminal telopeptide of type I collagen (ICTP) reflect extracellular matrix reformation and degradation, respectively, in the infarct healing processes, we measured these serum concentrations by RIA and compared their values with left ventricular (LV) indices obtained by left ventriculography. We studied 13 consecutive patients with their first AMI who underwent successful reperfusion. Blood samples were taken the day of admission and on days 2, 3, 4, 5, 7, and 14. LV volume indices were determined at 1 month after AMI, when LV remodeling was almost completed. The serum concentrations of both PICP and ICTP changed in a time-dependent manner. The average serum PICP concentration was lower than 1 SD below the mean control values on days 2 and 3 and increased thereafter, returning to the lower end of the control range at day 14. The area under the curve (AUC) for PICP was significantly correlated with the LV end systolic (ES) and end diastolic (ED) volume indices and LV ejection fraction for the first 14 days after AMI. The serum PICP on days 5-14 was inversely correlated or tended to be correlated with the LVES and LVED volume indices. The average serum ICTP concentrations on admission were within the control range, began to increase on day 2, and reached maximal concentrations on day 5, remaining at a plateau concentration until day 14. Although the AUC of ICTP for 14 days, the ICTP concentrations on days 1 and 14, and the minimal and maximal concentrations were significantly correlated with creatine kinase (CK) release and the period from AMI onset to the peak CK time, the concentrations were not significantly correlated with any LV indices except for the concentration on day 4, which was weakly correlated with the LVES volume index. The serum concentrations of PICP showed a significant time-dependent change that correlated with LV indices, indicating that PICP may provide additional information for evaluating the healing process because it affects LV remodeling after AMI. Although the serum concentration of ICTP changed in association with CK release, the ICTP concentration was found to be a poor indicator for LV indices.     

Cellulolytic activity of aerobic soil actinomycetes

The cellulolytic activity of several aerobic soil actinomycetes against insoluble cellulose and soluble cellulose derivatives (CMC-carboxymethylcellulose) was studied. From the soil, 8 actinomycete strains were isolated after enrichment growth and purification on the same synthetic medium. The actinomycete strains were able to degrade insoluble cellulose, with the production of cellobiose and various oligosaccharide intermediates as degradation products, indicating the random attack of the cellulose chain. The actinomycete strains showed also a great activity against soluble cellulose (CMC). The viscosity of CMC solutions decreased rapidly and was followed by an increase in reducing compounds. The degree of substitution of CMC solutions had an effect on the degradation by the actinomycetes. The degree of polymerization did not affect the rate of hydrolysis, however.     

The cell wall-anchored Streptomyces reticuli avicel-binding protein (AbpS) and its gene

Streptomyces reticuli produces a 35-kDa cellulose-binding protein (AbpS) which interacts strongly with crystalline forms of cellulose (Avicel, bacterial microcrystalline cellulose, and tunicin cellulose); other polysaccharides are recognized on weakly (chitin and Valonia cellulose) or not at all (xylan, starch, and agar). The protein could be purified to homogeneity due to its affinity to Avicel. After we sequenced internal peptides, the corresponding gene was identified by reverse genetics. In vivo labelling experiments with fluorescein isothiocyanate (FITC), FITC-labelled secondary antibodies, or proteinase K treatment revealed that the anchored AbpS protrudes from the surfaces of the hyphae. When we investigated the hydrophobicity of the deduced AbpS, one putative transmembrane segment was predicted at the C terminus. By analysis of the secondary structure, a large centrally located alpha-helix which has weak homology to the tropomyosin protein family was found. Physiological studies showed that AbpS is synthesized during the late logarithmic phase, independently of the carbon source.     

Long-term sequential determination of behavioral ontogeny of 5-HT1A and 5-HT2 receptor functions in the rat

Activation of 5-hydroxytryptamine1A (5-HT1A) receptors in rats produces hypothermia and a number of behaviors [hindleg abduction (HLA), lateral head-weaving (LHW), forepaw treading (FPT), flat body posture (FBP), rollover (RO), tremor (T), and straub tail (ST)] known collectively as the serotonin syndrome (SS). Stimulation of 5-HT2A receptors produces wet-dog shakes (WDS), whereas 5-HT2C sites induce back muscle contraction (BMC). We investigated the functional ontogeny of the cited receptors in rat pups on postnatal days (PD) 7, 14, 18, 22, 28, 35, 60, and 120 by using (1) the 5-HT1A agonist 8-hydroxy-2-dipropylaminotetralin (0, 1.25, and 5 mg/kg) to induce the SS and hypothermia and (2) the 5-HT2A/C agonist (+/-)-1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane (0, 0.5, and 4 mg/kg) to produce both WDS and BMC. The age of onset for most symptoms of SS [FBP, HLA, RO, and T] was the first week of life. They attained maximal intensities at ages 7 to 14 days, after which their maxima either reduced or dissipated to zero. Per contra, the onset of LHW and FPT required 14 to 18 days, and their maxima developed later. The onset of (+/-)-1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane-induced WDS occurred after PD 14, and by PD 18, it reached its maximal intensity, which persisted up to PD 60, after which it declined. The onset of BMC was evident on PD 28 and attained its maximal frequency at ages 90 to 120 days. The results show that different components of SS appear within 14 days of birth, but they mature differentially, whereas the hypothermic effect of 5-HT1A receptors remains relatively constant during aging. The times of onset and maturation of WDS were intermediate (between the second and third weeks of life), whereas BMC required 1 to 2 months for its appearance and maturation.     

Bioavailability and pharmacokinetics of beta-methyldigoxin after multiple oral and intravenous doses

To obtain true half lives, glycoside elimination from six healthy subjects was studied for 14 days after multiple intravenous doses or oral administration of a daily maintenance dose of beta-methyldigoxin 0.3 mg. After oral or intravenous administration of beta-methyldigoxin ceased, the plasma concentrations declined from the 14th to the 16th days with a half life of 1.7 days. From the 16th to the 20th day a change from a shorter to a longer half life of 2.8 and 2.9 days was observed. Similar half lives were found in urine: after the last dose the initial slope from the 14th to the 16th day had a half life of 1.8 days, and the terminal slope had one of 3.2 days. The results indicate release of the glycoside from slowly equilibrating tissues.     

An observation on subsurface defects of ultra high molecular weight polyethylene due to rolling contact

A double-blind, randomized, parallel study in 167 hospitalized patients with major depression and melancholia was conducted to determine if rapidly escalated doses of venlafaxine produced an earlier response, compared with rapidly escalated doses of imipramine. The daily dose of venlafaxine was rapidly increased to 375 mg/day over a five-day period, was maintained at this level for 10 days, and then was reduced to 150 mg/day for the remainder of the study. The imipramine dose was rapidly increased to 200 mg/day over five days and was maintained at this level to the end of the study. The primary efficacy variables were time to response and time to sustained response on the HAM-D and MADRS. No differences in the response rates on the HAM-D or MADRS were observed between treatments. However, among patients who demonstrated a response on the HAM-D, there was a significantly faster onset of response (p = 0.036) and sustained response (p = 0.018) in the venlafaxine group. The median time to response on the HAM-D among responders was 14 days with venlafaxine and 21 days with imipramine. However, no differences between treatments were observed among responders on the MADRS (median time to response: 15 days for venlafaxine, 18 days for imipramine). Study events were reported in 69% of venlafaxine-treated patients and 76% of imipramine-treated patients. In severely depressed patients with melancholia, a faster onset of response was observed with venlafaxine on the HAM-D, but not the MADRS, and maximal tolerated doses of venlafaxine and imipramine were comparable for overall efficacy. These results confirm and extend previous observations and suggest that venlafaxine may have an early onset of action and may produce a rapid response in hospitalized patients with severe depression complicated by melancholia.     

The role of apoptosis in the resolution of T cell-mediated cutaneous inflammation

We have investigated cutaneous purified protein derivative-induced delayed-type hypersensitivity (DTH) responses in healthy volunteers to determine features associated with both the generation and resolution of the reaction. The clinical peak of the response occurred at day 3; however, T cell numbers were maximal on day 7. There was a preferential increase of CD4+ CD45RO+ T cells on day 7, which was largely due to proliferation, since a mean of 19% was in cycle. The proliferation of this subset was associated with the presence of IL-15, which was expressed as early as 12 h, and IL-2, which showed peak expression at 7 days. By day 14, there was a significant decrease in both the mean T cell number/unit area and IL-2 and IL-15 expression in perivascular infiltrates. Maximal CD95 (Fas/Apo-1) ligand and TNF-alpha expression were observed at 7 days and were associated with the presence of 1.83% (range 0.81-2.48%) apoptotic T cells. At 14 days, CD95 ligand and TNF-alpha expression were reduced significantly, and the presence of 2.5% (range 1.5-3.75%) of apoptotic T cells at this time was probably due to cytokine deprivation, associated with decreased Bcl-2 relative to Bax expression. The induction and resolution of the Mantoux reaction may depend on the expression of cytokines, such as IL-2 and IL-15, which regulate both proliferation and apoptosis in T cells. Failure to control either of these phases of the Mantoux reaction may contribute to the chronicity of inflammatory responses in certain cutaneous diseases.     

Effects of hyaluronic acid/carboxymethylcellulose gel on bowel anastomoses in the New Zealand white rabbit

Intra-abdominal adhesions form in more than 90% of patients undergoing major abdominal surgery and can lead to significant complications. Application of a bioresorbable gel consisting of chemically modified hyaluronic acid (HA) and carboxymethylcellulose (CMC) has shown promise as a means of preventing intra-abdominal adhesions, but there have been concerns that the presence of the gel might interfere with the integrity and healing of bowel anastomoses. We tested the effects of HA/CMC gel on adhesion formation and anastomotic healing in 60 New Zealand white rabbits after transection and complete (100%) or incomplete (90%) anastomosis of the ileum. Half of the animals underwent application of HA/CMC gel and half served as control subjects. Animals were killed at 4, 7, or 14 days after surgery. Anastomotic adhesions were scored in a blinded fashion. Integrity of the anastomosis was tested by measuring bursting pressure at the anastomotic site and in an adjacent section of intact bowel. With complete anastomosis, HA/CMC gel significantly reduced adhesion formation at 7 and 14 days after surgery (P<0.05), but gel application did not inhibit adhesion formation when the anastomosis was incomplete. Anastomosed segments of bowel burst at a lower pressure than intact bowel 4 days after surgery, but bursting pressures were normal at 7 and 14 days. Burst pressures of anastomoses receiving an application of HA/CMC gel were nearly identical to control anastomoses at all three time points. HA/CMC gel did not interfere with the normal healing process of bowel anastomoses. Furthermore, HA/CMC gel decreased adhesion formation after complete anastomoses, yet it did not affect adhesion formation in the presence of anastomotic disruption.     

Effect of the age of the culture and the composition of the medium on alkaloid biosynthesis by Penicillium gorlenkoanum

The production of the alkaloids costaclavine and epicostaclavine by Penicillium gorlenkoanum was studied as a function of the culture age and the composition of the growth medium. The alkaloids were found in the mycelium and, in great quantities, in the cultural broth. The production of the extracellular alkaloids started from the first days of growth and run in parallel to the biomass accumulation; the synthesis of costaclavine and epicostaclavine was maximal at the end of the logarithmic-stationary growth phases. The medium supplied with mannitol, succinic acid and 1% KH2PO4 was optimal for epicostaclavine synthesis. A carbohydrate or organic acid substitution as well as a variation in the concentration of phosphate changed the proportion between epicostaclavine and costaclavine contents. The biosynthesis of epicostaclavine was inhibited almost entirely by the glucose deficiency (2%) in the medium. This glucose concentration, phosphate excess (10 g/l), and the presence of citric or tartaric acids created favourable conditions for costaclavine biosynthesis.     

Phase I study of interleukin-6 in children with solid tumours in relapse

The aim of this study was to evaluate the feasibility, toxicity and efficacy of escalating doses of subcutaneous recombinant interleukin-6 (IL-6) in children with solid tumours in relapse. Recombinant IL-6 was administered subcutaneously once daily for 14 consecutive days, with a 14 day follow-up period. The starting dose for IL-6 was 1 microgram/kg/day and was escalated in subsequent patients groups until 10 micrograms/kg. Doses were escalated every 3 patients, provided that grade III or IV organ toxicity did not occur at the preceding dose level. Twelve patients were treated, three at each dose level. No grade 3-4 major organ toxicity was observed. Flu-like symptoms and fatigue were the most common side effects. All these symptoms resolved after the end of IL-6 administration. Significant increases in acute-phase proteins (CRP [C reactive protein], fibrinogen) and ESR (Erthrocyte sedimentation rate) were observed in all patients. Stimulatory effects on thrombocytopoiesis were observed at every dose level, and were maximal at 5 micrograms/kg and 10 microgram/kg. There was no tumour response observed during IL-6 administration. Pharmacokinetic profiles performed in 3 patients are consistent with previous reports in adults. IL-6 is a promising new cytokine for paediatric oncology, in particular to increase thrombocyte counts. We recommend that further studies in children proceed at a dose of 5-10 micrograms/kg/day in a once or, better, twice daily administration.     

Effect of dexamethasone on erosette formation by lymphoid cells (author''s transl)

The corpora lutea (CL) of the hamster secrete progesterone on days 1 and 2 of the oestrous cycle before marked regression at pro-oestrus (day 4) virtually eliminates them from the ovary. Luteal protein and RNA reached their maximum values on day 2 and declined up to day 4. DNA was constant throughout the cycle substantiating the importance of cellular hypertrophy rather than hyperplasia in the growth of the CL. Concentrations of cholesterol and its esters were unchanged between days 1 and 3 but almost doubled in concentration on day 4. Glucose-6-phosphate dehydrogenase activity was maximal on days 2 and 4, apparently associated on these days with steroidogenesis and lipid metabolism, respectively. A significant increase in acid phosphatase activity occurred on day 3 reaching maximal values on day 4, probably accounting for the rapid regression of the CL. The maximal concentration of 3beta-hydroxysteroid dehydrogenase in CL was on day 1, with a gradual decline over the next 3 days.     

Effect of temperature on growth and activity of a methanogenic culture utilising acetate

Studies with a methanogenic culture enriched for use of acetic acid showed that this culture had an optimum growth temperature of 35 degrees C, with only small differences for other temperatures between 30 and 40 degrees C. The optimum temperature was the same when determined on the basis of biomass production rate during the exponential (log) phase of growth (0.08-0.09 day-1, at 35 degrees C), amount of biomass present at the end of the log phase (100 mg/l), activity of the biomass (rate of conversion in millimoles per day per milligram (dry wt.) biomass present, 0.08 at end of log phase), or biomass yield (mg (dry wt.) biomass produced per millimole acetic acid converted, 1.0-1.1). Temperatures outside the range 30 to 40 degrees C caused marked reductions in the above parameters. The maximum temperature for growth was 42-44 degrees C; the minimum, below 15 degrees C, the lowest temperature studied. Acetic acid conversion to methane was 0.8-1.0 mol/mol, and was independent of temperature.     

Body composition and glucose metabolism in hypertensive middle-aged males

The growth curves of 2 different strains of P. brasiliensis were determined. Cultures were made in a dialyzed trypticase soy broth and the growth assesed at selected intervals by means of viable cell counts. In the yeast form, both strains exhibited un uniform pattern of growth; the mycelial forms were also similar although one of the strains survived for a longer period of time. When the 2 yeast curves were compared with the mycelial ones, large differences were noticed. Thus, the mean survival time for the yeasts was 13.5 days while it was 50.25 days for the mycelia. During the exponential phase, the mean rate of growth was accelerated for the yeasts (0.110) in comparison with the one exhibited by the mycelia (0.0265). Irrespective of the form of growth and for both strains, death occurred abruptly, a few hours after a period when colony counts were high, indicating that the fugus was viable at the preceeding interval.     

Glutamine metabolism is changed in lymphocytes from aged rats

Changes in the protein content, maximal activity, and Km of phosphate-dependent glutaminase were measured in the lymphoid organs (thymus, spleen, and mesenteric lymph nodes) from just-weaned, mature (3 months), and aged rats (15 months). Also, [U-14C] glutamine transport and decarboxylation and the production of glutamate and aspartate from 2 and 20 mM glutamine were measured in incubated mesenteric lymph node lymphocytes. The ageing process induced a reduction in the protein content of the thymus and spleen, as well as the phosphate-dependent glutaminase activity in the thymus and isolated lymphocytes. The Km of phosphate-dependent glutaminase, however, was not affected by the process. Ageing reduced [U-14C] glutamine decarboxylation and increased glutamate and aspartate production in incubated lymphocytes. The results indicate that the ageing process does modify several aspects of glutamine metabolism in lymphocytes: reduces maximal glutaminase activity and [U-14C] glutamine decarboxylation and increases the Km for [U-14C] glutamine uptake and the production of glutamate and aspartate.     

Neurochemical and behavioural effects of neurotensin vs [D-Tyr11]neurotensin on mesolimbic dopaminergic function

Changes in bronchoalveolar lavage fluid (BALF) and blood were examined to assess the toxic effects of diborane (B2H6, CAS: 19287-45-7) on the lung. Male Wistar rats were exposed to diborane at 20 ppm (intended concentration) for 4 h (phase I study) to evaluate time-course changes up to 14 days, and at 10 or 1 ppm (intended concentrations) to assess the dose-effect relationship after 3 days (phase II study). BALF parameters [leukocyte counts, alpha 1-antitrypsin (alpha 1-AT), superoxide dismutase (SOD), total protein, phospholipids etc.] were examined and biochemical and histopathological studies were also carried out. In the phase I study, neutrophils (%) in BALF increased on the day of exposure and then decreased gradually for 3 days. Rapid and marked increases in alpha 1-AT and SOD activity in BALF were detected on the day of exposure, and phospholipids had sharply increased on day 3. After 14 days, these parameters in the exposed rats had returned to their background level and alpha 1-AT decreased significantly. In the phase II study, total protein, alpha 1-AT activity and phospholipids in BALF showed dose-dependent increases, and serum alpha 1-AT activity increased significantly. Alveolar capillary and alveolar cell damage were confirmed in rats exposed to 20 ppm, 10 ppm or 1 ppm diborane for 4 h by evaluating the parameters examined. The protection system appeared to start operating immediately after exposure, and the recovery mechanism seemed to start operating 1 day after exposure and cease by day 14. The no-observed-effect level could not be observed.