High Concentrations Of Dextrose Research Articles

High glucose intake exacerbates experimental autoimmune prostatitis through mitochondrial reactive oxygen species-dependent TGF-β activation-mediated Th17 differentiation

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a common inflammatory immune disease of the urogenital system. High glucose intake is considered to be a potential promoter of autoimmune diseases. However, the influence of high glucose intake on CP/CPPS is unknown. This research aimed to explore the influences of high glucose intake on experimental autoimmune prostatitis (EAP), a valid animal model of CP/CPPS, and the underlying mechanism. NOD mice received 20% glucose water or normal water treatment during EAP induction. EAP severity and Th17 cell responses were evaluated. Then, we explored the effects of an IL-17A neutralizing antibody, an inhibitor of TGF-β, the reactive oxygen species (ROS) inhibitor NAC, and the mitochondrial ROS (mtROS) antioxidant MitoQ on glucose-fed EAP mice. The results demonstrated that high glucose intake aggravated EAP severity and promoted Th17 cell generation, which could be ameliorated by the neutralization of IL-17A. In vitro experiments showed that high dextrose concentrations promoted Th17 cell differentiation through mtROS-dependent TGF-β activation. Treatment with TGF-β blockade, NAC, or MitoQ suppressed Th17 cell generation both in vivo and in vitro, resulting in the amelioration of EAP manifestations caused by high glucose intake. This study revealed that high glucose intake exacerbates EAP through mtROS-dependent TGF-β activation-mediated Th17 differentiation. Our results may provide insights into the molecular mechanisms underlying the detrimental effects of an environmental factor, such as high glucose intake, on CP/CPPS.

Maltodextrin Use in Persistent Neonatal Hypoglycemia; Audit Report of a Single Center Experience

Background: Neonatal hypoglycemia is known to cause significant neuronal damage and poor neurodevelopmental outcomes. Consensus guidelines are lacking for the management of persistent neonatal hypoglycemia and hyperinsulinism which often requires high concentrations of dextrose and medications. Although used in the pediatric population with persistent hypoglycemia, only a few case reports are published regarding the use of Maltodextrin supplementation in persistent neonatal hypoglycemia due to transient hyperinsulinism. Objective: To audit the use of Maltodextrins in the management of persistent neonatal hypoglycemia due to transient hyperinsulinism in neonates. Audit design: A retrospective chart review (CERNER electronic data) of all cases with persistent neonatal hypoglycemia who received Maltodextrin supplementation for a period of 3½ years between July 2018 and December 2021. Results: A total of 18 neonates received Maltodextrin supplementation for neonatal hypoglycemia during the audit period. 16/18 (89%) neonates who received Maltodextrin supplementation were weaned off from intravenous dextrose within 1 week without major side effects or severe rebound hypoglycemia. Two out of 18 babies who received Maltodextrin needed Diazoxide supplementation for persistent hypoglycemia. Conclusion: The results of our audit are promising, yet further research and randomized controlled studies are needed to systematically evaluate the findings of this audit regarding Maltodextrin supplementation for the management of neonatal hypoglycemia with transient hyperinsulinism.

Omega-3 Fatty Acids Inhibit Endoplasmic Reticulum (ER) Stress in Human Coronary Artery Endothelial Cells

The biological effects of fatty acids differ by their structure. Saturated fatty acids and trans-fatty acids are recognized as promoters of coronary artery disease (CAD), while monounsaturated and omega-3 fatty acids may have salutary effects. Since cellular stress is recognized as a fundamental driver of CAD, the effect of these fatty acids on endoplasmic reticulum (ER) stress in human coronary artery endothelial cells (HCAECs) was measured using the ER stress-responsive alkaline phosphatase (ES-TRAP) assay. Docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and eicosapentaenoic acid ethyl ester (EPA-EE) suppressed ER stress induced with pharmacologic (tunicamycin) and physiologic (high-dextrose concentration) ER stress inducers. In tunicamycin-treated cells, DHA reduced the expression of unfolded protein response (UPR) markers such as phosphorylation of inositol requiring enzyme 1α (IRE1α) and protein kinase R-like endoplasmic reticulum kinase (PERK) and increased activating transcription factor 6 (ATF6) and glucose regulated protein 78 (GRP78) expression. Similarly, treatment with both oleic acid and arachidonic acid, but not elaidic acid (a trans-fatty acid), suppressed both tunicamycin and high-dextrose-induced ER stress while treatment with saturated fatty acids (C14 : 0, C16 : 0, and C18 : 0) enhanced both tunicamycin and high-dextrose-induced ER stress. The latter fatty acids at higher concentrations caused cytotoxicity. These results indicate that omega-3 fatty acids as well as select unsaturated fatty acids and arachidonic acid suppress ER stress in HCAEC.

Effect of the temperature and osmotic stress on the growth and cell viability of Candida maltosa

The present research attempted to observe the temperature and osmotic stress effects on yeast species in cheese. The Candida maltosa yeast was isolated from locally made raw cheese samples, and it was identified by its biochemical properties, followed by using the BIOLOGTM microbial identification system to confirm species level identification. The study investigate about Candida maltosa's ability to grow and develop a budding pattern under high temperatures up to 44°C and osmotic stress for 72 h. Osmotic stress tolerance was studied at 32.5°C in different concentrations of dextrose (0.04 g/l, 0.12 g/l, 0.2 g/l, 0.28 g/l, and 0.36 g/l) and sucrose (0.02 g/l, 0.06 g/l, and 0.36 g/l), respectively. Cell growth of the C. maltosa was measured by optical density at 600nm (OD600) and the enumeration of colony forming units (CFUs) on the agar plates up to 300 m. The obtained result indicated the optimal growth pattern at 32.5°C and complete growth retardation at 44°C with the high concentrations of dextrose (0.36 g/l) and sucrose (0.38 g/l). Particularly, C. maltosa budding could only survive 240 m at 37°C to 40°C and was suppressed at 44°C. The experimental findings demonstrated the stress response in yeast cells in the phenotypic level with the existing acquaintance on the osmotic stress response actions in C. maltosa. Bangladesh J. Sci. Ind. Res. 58(2), 71-78, 2023

Articles That May Change Your Practice: Dextrose Administration

Paramedics typically administer high concentrations of dextrose to patients experiencing conditions such as hyperkalemia or hypoglycemia. The treatment typically involves the administration of 25 g highly concentrated (50%) dextrose. This dose may cause harm and lead to difficulties regulating posttreatment blood glucose levels. Peripheral administration of high concentrations of dextrose may be associated with phlebitis and extravasation injuries. Lower concentrations of dextrose, such as 10%, may be a safer alternative in preventing the adverse effects of boluses of 50% dextrose. In situations in which dextrose 50% in water (D50W) is not readily available, as has been the case during the pandemic due to severe acute respiratory syndrome coronavirus 2, there may be a need for safer alternatives. Russell D. MacDonald, MD, MPH, FCFP, FRCPC, is the former medical director at Ornge Transport Medicine; the current medical director at Toronto Paramedic Services; a professor in the Faculty of Medicine at the University of Toronto; and an attending staff member at Sunnybrook Health Sciences Centre in Toronto, Ontario, Canada. He can be reached at [email protected].

Central venous catheter-associated thrombosis in children with congenital hyperinsulinism

SummaryCongenital hyperinsulinism (CHI) is an important cause of severe hypoglycaemia in infancy. To correct hypoglycaemia, high concentrations of dextrose are often required through a central venous catheter (CVC) with consequent risk of thrombosis. We describe a series of six cases of CHI due to varying aetiologies from our centre requiring CVC for the management of hypoglycaemia, who developed thrombosis in association with CVC. We subsequently analysed the incidence and risk factors for CVC-associated thrombosis, as well as the outcomes of enoxaparin prophylaxis. The six cases occurred over a 3-year period; we identified an additional 27 patients with CHI who required CVC insertion during this period (n = 33 total), and a separate cohort of patients with CHI and CVC who received enoxaparin prophylaxis (n = 7). The incidence of CVC-associated thrombosis was 18% (6/33) over the 3 years, a rate of 4.2 thromboses/1000 CVC days. There was no difference in the frequency of genetic mutations or focal CHI in those that developed thromboses. However, compound heterozygous/homozygous potassium ATP channel mutations correlated with thrombosis (R2 = 0.40, P = 0.001). No difference was observed in CVC duration, high concentration dextrose or glucagon infused through the CVC. In patients receiving enoxaparin prophylaxis, none developed thrombosis or bleeding complications. The characteristics of these patients did not differ significantly from those with thrombosis not on prophylaxis. We therefore conclude that CVC-associated thrombosis can occur in a significant proportion (18%) of patients with CHI, particularly in severe CHI, for which anticoagulant prophylaxis may be indicated.Learning points:CVC insertion is one of the most significant risk factors for thrombosis in the paediatric population.Risk factors for CVC-associated thrombosis include increased duration of CVC placement, malpositioning and infusion of blood products.To our knowledge, this is the first study to evaluate CVC-associated thrombosis in patients with congenital hyperinsulinism (CHI).The incidence of CVC-associated thrombosis development is significant (18%) in CHI patients and higher compared to other neonates with CVC. CHI severity may be a risk factor for thrombosis development.Although effective prophylaxis for CVC-associated thrombosis in infancy is yet to be established, our preliminary experience suggests the safety and efficacy of enoxoaparin prophylaxis in this population and requires on-going evaluation.

MON-082 Symptomatic Icodextrin Right Pleural Effusion From Suspected Pleuro-peritoneal Communication: The Utility of Simultaneous Biochemical Fingerprint Analysis of Drained Pleural Fluid and Peritoneal Dialysis Fluid

Symptomatic pleural effusion secondary to pleuro-peritoneal communication in patients on peritoneal dialysis occurs in about 2% of patients on CAPD. The classic presentation is that of a low protein high-glucose pleural aspirate consistent with the high dextrose concentrations present in standard PD fluids, hence, the name, “sweet hydrothorax”. Nevertheless, the increasing use of Icodextrin calls for an innovative bedside diagnostic approach since Icodextrin does not contain high concentrations of dextrose after all.

Inhibition of Pro-Inflammatory Cytokine Secretion by Select Antioxidants in Human Coronary Artery Endothelial Cells.

Inflammatory and oxidative stress in endothelial cells are implicated in the pathogenesis of premature atherosclerosis in diabetes. To determine whether high-dextrose concentrations induce the expression of pro-inflammatory cytokines, human coronary artery endothelial cells (HCAEC) were exposed to either 5.5 or 27.5 mM dextrose for 24-hours and interleukin-1β (IL-1β), interleukin-2 (IL-2), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor α (TNF α) levels were measured by enzyme immunoassays. To determine the effect of antioxidants on inflammatory cytokine secretion, cells were also treated with α-tocopherol, ascorbic acid, and the glutathione peroxidase mimetic ebselen. Only the concentration of IL-1β in culture media from cells exposed to 27.5 mM dextrose increased relative to cells maintained in 5.5 mM dextrose. Treatment with α-tocopherol (10, 100, and 1,000 μM) and ascorbic acid (15, 150, and 1,500 μM) at the same time that the dextrose was added reduced IL-1β, IL-6, and IL-8 levels in culture media from cells maintained at 5.5 mM dextrose but had no effect on IL-1β, IL-6, and IL-8 levels in cells exposed to 27.5 mM dextrose. However, ebselen treatment reduced IL-1β, IL-6, and IL-8 levels in cells maintained in either 5.5 or 27.5 mM dextrose. IL-2 and TNF α concentrations in culture media were below the limit of detection under all experimental conditions studied suggesting that these cells may not synthesize detectable quantities of these cytokines. These results suggest that dextrose at certain concentrations may increase IL-1β levels and that antioxidants have differential effects on suppressing the secretion of pro-inflammatory cytokines in HCAEC.

Asymmetrical cross-talk between the endoplasmic reticulum stress and oxidative stress caused by dextrose.

Oxidative and endoplasmic reticulum (ER) stresses are implicated in premature cardiovascular disease in people with diabetes. The aim of the present study was to characterize the nature of the interplay between the oxidative and ER stresses to facilitate the development of therapeutic agents that can ameliorate these stresses. Human coronary artery endothelial cells were treated with varying concentrations of dextrose in the presence or absence of three antioxidants (alpha tocopherol, ascorbate and ebselen) and two ER stress modifiers (ERSMs) (4-phenylbutyrate and taurodeoxycholic acid). ER stress was measured using the placental alkaline phosphatase assay and superoxide (SO) generation was measured using the superoxide-reactive probe 2-methyl-6-(4-methoxyphenyl)-3,7-dihydroimidazo[1,2-A]pyrazin-3-one hydrochloride chemiluminescence. The SO generation was increased with increasing concentrations of dextrose. The ER stress was increased with both low (0 and 2.75 mM) and high (13.75 and 27.5 mM) concentrations of dextrose. The antioxidants inhibited the dextrose induced SO production while in high concentrations they aggravated ER stress. The ERSM reduced ER stress and potentiated the efficacy of the three antioxidants. Tunicamycin-induced ER stress was not associated with increased SO generation. Time course experiments with a high concentration of dextrose or by overexpressing glucose transporter one in endothelial cells revealed that dextrose induced SO generation undergoes adaptive down regulation within 2 h while the ER stress is sustained throughout 72 h of observation. The nature of the cross talk between oxidative stress and ER stress induced by dextrose may explain the failure of antioxidant therapy in reducing diabetes complications.

Influence of heat shock and osmotic stresses on the growth and viability of Saccharomyces cerevisiae SUBSC01.

BackgroundWith a preceding scrutiny of bacterial cellular responses against heat shock and oxidative stresses, current research further investigated such impact on yeast cell. Present study attempted to observe the influence of high temperature (44–46 °C) on the growth and budding pattern of Saccharomyces cerevisiae SUBSC01. Effect of elevated sugar concentrations as another stress stimulant was also observed. Cell growth was measured through the estimation of the optical density at 600 nm (OD600) and by the enumeration of colony forming units on the agar plates up to 450 min.ResultsSubsequent transformation in the yeast morphology and the cellular arrangement were noticed. A delayed and lengthy lag phase was observed when yeast strain was grown at 30, 37, and 40 °C, while at 32.5 °C, optimal growth pattern was noticed. Cells were found to lose culturability completely at 46 °C whereby cells without the cytoplasmic contents were also observed under the light microscope. Thus the critical growth temperature was recorded as 45 °C which was the highest temperature at which S. cerevisiae SUBSC01 could grow. However, a complete growth retardation was observed at 45 °C with the high concentrations of dextrose (0.36 g/l) and sucrose (0.18 g/l). Notably, yeast budding was found at 44 and 45 °C up to 270 min of incubation, which was further noticed to be suppressed at 46 °C.ConclusionsPresent study revealed that the optimal and the critical growth temperatures of S. cerevisiae SUBSC01 were 32.5 and 45 °C, respectively; and also projected on the inhibitory concentrations of sugars on yeast growth at that temperature.

Tandem mass spectrometric identification of dextrose markers in dried-blood spots from infants receiving total parenteral nutrition

Background The false positive rate for the newborn screening of disorders of amino acid metabolism for premature infants is higher than full term infants. This may be due to very low birth weight infants receiving high concentrations of amino acids from total parenteral nutrition (TPN) administration and/or immature metabolism. An investigation of the possible influence of TPN on screening of premature infants resulted in the detection of three unusual peaks in the tandem mass spectrometry (MS/MS) acylcarnitine profile. These markers were closely correlated with the detection of very high multiple amino acid increases in the profiles of newborns administered with TPN and who were ultimately found to be normal and free of inherited metabolic disorders. Methods TPN solutions contain a concentrated mixture of amino acids and dextrose and other nutrients in saline. Due to its high concentration and suggestion of a carbohydrate, it was hypothesized that dextrose ( d-glucose) was the contaminant and source of the markers detected. Dextrose, stable isotope-labeled 13C 6-dextrose and various TPN solutions were analyzed directly or after enrichment in whole blood by multiple MS/MS acquisition modes including MS-only, product and precursor ion and neutral loss scans. Results Analysis of dried-blood spots (DBS) prepared from whole blood spiked with TPN solutions containing 12.5% dextrose and amino acid formulations designed to deliver 2.5 gm/kg/day of an amino acid mixture had moderate increases of all 3 dextrose markers detected at m/z 325, 399 and 473 as compared to controls. MS-only scans, product and precursor ion scans of dextrose and 13C 6-dextrose in positive ion mode confirmed that these 3 peaks are derived from dextrose. Mass spectral analysis of labeled and unlabeled dextrose suggested that these peaks were dimers derived from dextrose. Conclusion The identification of dextrose markers in DBS indicates that high concentrations of dextrose were present in blood and the likely source was contamination by TPN solutions most likely occurring during a sample collection process.

Statins Prevent Dextrose-Induced Endothelial Barrier Dysfunction, Possibly Through Inhibition of Superoxide Formation

Statins may have favorable effects on endothelial barrier function, possibly through reduction of oxidative stress and modulation of expression of vasoactive proteins. The permeability of human umbilical endothelial cells in culture to a group of fluorescein isothiocyanate dextrans of different molecular weights were studied under various experimental conditions. Superoxide anion production was measured with an ethidium bromide fluorescence method. Cellular endothelin 1 mRNA and endothelin 1 in culture media were measured with Northern blots and enzyme immunoassays, respectively. Rosuvastatin (10 nmol/l) normalized the 500 mg/dl dextrose-induced permeability changes. Superoxide anion production induced by 500 mg/dl dextrose was inhibited by therapeutic concentrations of rosuvastatin or simvastatin (10 nmol/l), whereas the increased levels of cellular endothelin 1 mRNA and endothelin 1 in culture media was inhibited by supratherapeutic concentrations of statins (> or =0.1 micromol/l). In conclusion, 1) endothelial cell barrier dysfunction occurs in cells treated with high concentrations of dextrose, 2) statin treatment of endothelial cells normalizes barrier permeability, and 3) the favorable effects of statins may be attributed to the inhibition of the dextrose-induced increase in superoxide anions, whereas inhibition of endothelin expression was observed only at supratherapeutic concentrations.

Neonatal Peritoneal Dialysis

After completing this article, readers should be able to: 1. List the indications for peritoneal dialysis (PD) in neonates. 2. Delineate neonates who are poor candidates for PD. 3. Review the parameters of the PD prescription. 4. Review special nutrition considerations for neonates who are undergoing PD. 5. Review potential complications of PD in neonates. Peritoneal dialysis (PD) is generally considered the optimal dialysis modality for neonates. PD allows for the slow removal of fluid and solutes while avoiding hemodynamic instability. It is technically simple and, when necessary, can be performed continuously in the neonate hospitalized in the neonatal intensive care unit. In this review, we discuss the salient features of neonatal PD, including the rationale and indications for PD, its advantages and disadvantages, the PD prescription, nutritional considerations for the neonate undergoing PD, and the management of peritonitis. ### Rationale and Indications for Dialysis in Neonates Acute renal failure is common, occurring in as many as 23% of neonates hospitalized in neonatal intensive care units. There are excellent reviews in the literature that discuss the causes, pathophysiology, and medical management of acute renal failure in the neonate (see Acute Renal Failure Management in the Neonate in this issue of NeoReviews ). A partial list of the causes of acute renal failure in neonates is provided in Table 1. | Prerenal | || | | | Intrinsic | | | | Postrenal | | | Table 1. Causes of Acute Renal Failure The decision to initiate dialysis typically is necessitated by recalcitrant electrolyte abnormalities, worsening uremia, fluid overload, persistent acid-base abnormalities, …

Rapid adaptive down regulation of oxidative burst induced by high dextrose in human umbilical vein endothelial cells

To determine whether hyperglycemia-induced increase in oxidative burst undergoes adaptive changes, the time course of superoxide (SO) production in human umbilical vein endothelial cells treated with 13.75 mM (D250) or 27.5 mM dextrose (D500) was measured using the hydroethidine (HE) fluorescence method. The rate of SO production (mean±S.D., in arbitrary units) in cells treated with D500 during the first hour (0.758±0.367) or with D250 (0.618±0.126) was significantly higher than the rate observed in control cells treated with 100 mg/dl dextrose, (D100; 0.474±0.125) ( P<0.001). However, the rate of SO production during the second, third, fourth, and fifth hour was not significantly different from that measured in control cells. The fluorescence at baseline for control cells was 3.4±2.3 and for cells treated with D500 for 1, 2, 3, 4, and 5 h was 3.4±1.9, 15.2±2.5, 21.6±2.3, 27.4±3.4, and 31.8±4.3, respectively ( P<0.001). The increased baseline fluorescence suggests that the antioxidant pool may be depleted within the first hour of exposure to high concentrations of dextrose. The latter possibility is supported by the observation that treatment of cells with varying concentrations of ascorbate (15, 150, and 1500 μM) or α-tocopherol (10,100 and 1000 μM) prevents D500 induced increase in SO production. It is concluded that increased oxidative load in sustained chronic hyperglycemia is probably the result of depletion of antioxidant pool rather than secondary to sustained increase in SO production.

Antioxidant Power, Lipid Oxidation, Color, and Viability of Listeria monocytogenes in Beef Bologna Treated with Gamma Radiation and Containing Various Levels of Glucose

Ionizing radiation can be used to pasteurize ready-to-eat (RTE) meat products. Thermal processing of RTE meats that contain dextrose results in the production of antioxidants that may interfere with ionizing radiation pasteurization of RTE meat products. Beef bologna was manufactured with dextrose concentrations of 0, 2, 4, 6, and 8%. Antioxidant activity, as measured by the Ferric Reducing Antioxidant Power assay, increased with dextrose concentration but was unaffected by ionizing radiation. Lipid oxidation increased significantly in irradiated bologna (4 kGy) that contained dextrose. Hunter color analysis indicated that the addition of dextrose reduced the ionizing radiation-induced loss of redness (a-value) but promoted the loss of brightness (L-value). The radiation resistance, D10-value, of Listeria monocytogenes that was surface-inoculated onto bologna slices was not affected by dextrose concentration. L. monocytogenes strains isolated from RTE meats after listeriosis outbreaks were utilized. Increased antioxidant activity generated by thermal processing of dextrose in fine emulsion sausages does not present a barrier to radiation pasteurization of RTE meats. However, a high dextrose concentration in combination with gamma irradiation increases lipid oxidation significantly.

Does nutritional intervention in protein-energy malnutrition improve morbidity or mortality?

Although there is an association between malnutrition and a poor clinical outcome, it does not necessarily follow that providing nutrients to such patients will improve the outcome. In fact, a number of prospective randomized controlled trials have not been able to demonstrate that nutritional support does, in general, improve morbidity or mortality. Very few such trials have been performed in patients with renal disease. Three studies in patients with acute renal failure have suggested that patients receiving parenteral nutrition using essential amino acids as the nitrogen source have better outcomes than do patients receiving equicaloric amounts of glucose, but these studies cannot exclude the possibility that the intravenous infusion of high concentrations of dextrose is detrimental. Small studies have suggested that the provision of perdialytic nutrient infusions or enteral nutrient supplements can improve measurements of nutritional status, but none of these trials described the effect of the nutritional intervention on morbidity or mortality. Two small trials have raised the possibility that supplemental ketoacids may retard the progression of chronic renal failure. There is a need for large randomized controlled trials to establish or refute the efficacy of nutritional support in renal disease. Such trials should include a control group that is not receiving any nutritional support.

Effect of nutrient sources on growth and acetate production by Clostridium thermoaceticum

The economic viability of producing acetate from dextrose by Clostridium thermoaceticum is dependent on using low cost nutrients in the medium. Under conditions of nutrient depletion or high dextrose concentration, the cells decreased in numbers, reduced their rate of acetate production, and also produced a by-product (fructose). The best alternate nutrients were defatted soy flour with limited protein hydrolysis, corn steep liquor, and ethanol stillage. They gave comparable results to Bacto yeast extract from Difco but at a substantially lower cost.

Biosurfactant production by a soil pseudomonas strain growing on polycyclic aromatic hydrocarbons

The capacity of polycyclic aromatic hydrocarbon (PAH)-utilizing bacteria to produce biosurfactants was investigated. Twenty-three bacteria isolated from a soil contaminated with petroleum wastes were able to form clearing zones on mineral salt agar plates sprayed with solutions of PAHs. Naphthalene and phenanthrene were utilized as sole substrates. Biosurfactant production was detected by surface tension lowering and emulsifying activities from 10 of these strains grown in an iron-limited salt medium supplemented with high concentrations of dextrose or mannitol, as well as with naphthalene or phenanthrene. Glycolipid determinations showed that in cultures of Pseudomonas aeruginosa 19SJ on naphthalene, the maximal productivity of biosurfactants was delayed compared with that in cultures grown on mannitol. However, when small amounts of biosurfactants and naphthalene degradation intermediates were present at the onset of the cultivation, the delay was markedly shortened. Production of biosurfactants was accompanied by an increase in the aqueous concentration of naphthalene, indicating that the microorganism was promoting the solubility of its substrate. Detectable amounts of glycolipids were also produced on phenanthrene. This is the first report of biosurfactant production resulting from PAH metabolism.

Phaeotheca dimorphospora sp.nov.: description et caractéristiques culturales

An unknown fungus isolated from an elm branch and inhibitory against Ophiostoma ulmi in vitro is described as Phaeotheca dimorphospora sp.nov. This dematiaceous deuteromycete propagates by endoconidia released after exfoliation of chlamydospore outer wall, as in mother cells of the type species Phaeotheca fissurella. However, P. dimorphospora differs from the type species by producing hyaline secondary ameroconidia between the endoconidial masses. Other ameroconidia, similar to the secondary ameroconidia, are produced through the chlamydospore outer wall. The optimal growth temperature of P. dimorphospora is 23 °C, whereas it is 15.5 °C for the type species. On media containing a high dextrose concentration (30 g ∙ L−1), colonies of P. dimorphospora are gray and crustose and grow slowly, at least initially. Conversely, on media with a low dextrose concentration (5 or 10 g ∙ L−1) colonies have a faster growth rate and appear whitish or ivory and fluffy. Key words: Phaeotheca dimorphospora, diagnosis, inhibition, Ophiostoma ulmi, Dutch elm disease.

Relation between gastric emptying of albumin-dextrose meals and cholecystokinin release in man

The effect of intragastric dextrose on albumin-stimulated cholecystokinin (CCK) release was studied in five healthy subjects and was related to gastric emptying and pancreatobiliary secretions. When combined with low concentrations of dextrose (4 g/100 ml), a 500-ml solution of albumin (7 g/100 ml) was rapidly emptied from the stomach into the duodenum (T1/2: 35 min). This rapid gastric emptying resulted in an only transient stimulation of pancreatobiliary secretion and an integrated CCK release of 278 +/- 45 pM x 180 min. When the concentration of dextrose in the albumin solution was increased from 4 g/100 ml to 21 g/100 ml, gastric emptying rate was distinctly slower (T1/2: 78 min; P < 0.01) and pancreatobiliary secretions became sustained (P < 0.01). CCK release was markedly higher (900 +/- 421 pM x 180 min; P < 0.05) after ingestion of the solution containing a high dextrose concentration. Intraduodenal infusion of 21 g/100 ml dextrose (3.1 ml/min) failed to significantly stimulate plasma CCK levels (119 +/- 38 pM x 120 min). We suggest that the higher CCK release in response to intragastrically administered albumin solution containing high concentrations of dextrose may have been induced by augmented peptic digestion of albumin due to delayed gastric emptying and by increased enteral digestion of albumin due to increased pancreatobiliary outputs.