Dietary effects of phytoecdysones in the leek-moth,Acrolepiopsis assectella Zell. (Lepidoptera: Acrolepiidae)

Incorporation of certain phytoecdysones (ecdysterone, polypodine B, and ponasterone A) into a semisynthetic artificial diet induces pathophysiological effects in larvae of the leek-moth (Acrolepiopsis assectella Zell., Acrolepiidae). The effects include lethality of the newly hatched, first-instar larvae; special ecdysial failures associated with the appearance of larvae with two head capsules; and developmental anomalies during metamorphosis. The effective range of dietary ecdysteroid, as evaluated by larval mortality, varies from 25 to 250 ppm. The EC₅₀ value is 100 ppm for polypodine B and 130 ppm for ecdysterone. The dietary effects of the phytoecdysones are similar to the previously observed effects caused by the dried flowers, but not leaves, of the leek plant. However, the active compound of the leek flowers is a saponin.     

<Emphasis Type="Italic">N</Emphasis>-Acyl Taurines are Anti-Proliferative in Prostate Cancer Cells

Endocannabinoids have been implicated in cancer development and cause heterogenous effects in tumor cells, by inducing apoptosis, reducing migration, causing anti-angiogenic activity and alterations in the cell cycle resulting in growth arrest. Recently, several novel amides of fatty acids that are structurally related to endocannabinoids have been isolated from mammalian sources, although the functions of these fatty amides are not well studied. One group of these novel fatty acid amides are the N-acyl taurines (fatty acids conjugated to the amino acid taurine). This study examined if N-acyl taurines, specifically N-arachidonoyl taurine and N-oleoyl taurine could function in a similar way to endocannabinoids and result in cell cycle alterations or growth arrest in the human prostate adenocarcinoma cell line PC-3. PC-3 cells were treated with various concentrations of N-arachidonoyl taurine and N-oleoyl taurine and cell proliferation and viability was measured using resazurin and colony formation assays. Effects of N-acyl taurines on the cell cycle was measured using FACS analysis. Treatment with N-arachidonoyl taurine and N-oleoyl taurine resulted in a significant reduction in proliferation of PC-3 cells, even at concentrations as low as 1 μM. Treatment with N-oleoyl taurine resulted in an increased number of cells in the subG1 population, suggesting apoptosis, and a lower number of cells in S-phase of the cell cycle. In summary, our results show that novel biologically active lipids, the N-acyl taurines, result in reduced proliferation in PC-3 cells.     

Some factors influencing biogenic amines and polyamines content in Dutch-type semi-hard cheese

Biogenic amines (BA; histamine, tyramine, tryptamine, phenylethylamine, cadaverine) and polyamines (PA; putrescine, spermidine, spermine) content was determined in Dutch-type semi-hard cheese (ripening 176 days) using an experimental design two producers × two starter cultures × two fat contents. Content of quantitatively most important BA (tyramine and histamine) and PA (putrescine) in the cheese samples at the end of ripening varied in the range 5–392 and 22–59, and 1–132 mg kg⁻¹, respectively. Time of ripening accounted for (P < 0.01) 67, 67 and 76% of the explained variability of histamine, tyramine, and putrescine content, respectively. Histamine, tyramine, and putrescine content in cheese (Y, mg kg⁻¹) increased (P < 0.01) linearly with increasing time of ripening (X, days): Y = 0.24X−1.3 (R ² = 0.28), Y = 0.69X−18.9 (R ² = 0.24) and Y = 0.16X−1.3 (R ² = 0.04), respectively. Biogenic amines (sum of BA) were produced more than three times more rapidly with increasing time of ripening in the edge part of the cheese than in the core part. Both histamine and tyramine content in cheese was negatively correlated (P < 0.01) with counts of lactic acid bacteria (LAB) and counts of total anaerobes, respectively. Accordingly, only 3% of both LAB and enterococci (established tyramine producers) isolates were positive on tyrosine decarboxylase gene sequences using the PCR method.     

Quantitation of cell-associated doxorubicin by high-performance liquid chromatography after enzymatic desequestration

In a double blind study of 58 episodes of fever and profound neutropenia, children with cancer received either recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) or placebo, combined with identical antimicrobial therapy, i.e. imipenem, on admission. The criteria for discontinuation of therapy were identical. A difference was demonstrated both in the number of hospital days, totaling 252 days in the rhGM-CSF group and 354 in the placebo group, days receiving antibiotics (220 vs. 322), and in the resolution of neutropenia (4.5 days vs. 6.0 days; P < 0.05). The number of episodes requiring antimicrobial therapy for longer than 10 days was 5 of 28 (12%) in the rhGM-CSF group as opposed to 15 of 30 (50%) in the placebo group (P = 0.01). rhGM-CSF was well-tolerated. We conclude that rhGM-CSF was efficacious in accelerating myeloid recovery and reducing the length of hospitalization in febrile neutropenia.     

The diuretic effect of borocaptate sodium in rats and in patients with brain tumors

Kidney function changes after single-dose administration of borocaptate sodium were studied in rats and in patients with brain tumors. Changes of glomerular filtration rate (GFR) measured as 14C-inulin clearance and urine flow rate (UFR) after a slow intravenous injection of BSH (25 and 50 mg/kg b.w., respectively) were investigated in rats under pentobarbital anesthesia. The effect of BSH has been compared with that of its disulfide (BSSB) which is spontaneously generated by oxidation of BSH during storage. It was found that BSH decreases GFR in relation to dose and, in the same way, causes a temporary increase of UFR. On the other hand, BSSB (50 mg/kg) induced a large reversible decrease of GFR as well as a decrease of urine excretion. Measurements of GFR (inulin clearance), renal plasma flow (PAH clearance) and urine excretion were taken in a group of patients with brain tumors in which boron disposition after an infusion of BSH (25 mg/kg b.w. over 1 h) had been studied. An increase in urine production was the dominant effect (up to 200% of the initial value), with the alterations of GFR and RPF being of minor significance except in one patient with a GFR reduction up to almost 50% the original value. Kidney function changes after BSH or BSSB administration are supposedly related to the high retention of BSH in kidney.     

Synthesis of 1′-Aryl-1,3′-bi-β-carbolines and Their Saturated Counterparts

1-Aryl-β-carboline-3-carbaldehyde building blocks have been used as the starting materials for the synthesis of novel bis-β-carboline derivatives. In the two-step synthesis the Pictet–Spengler reaction was used before the dehydrogenation of the polycyclic compound to the aromatic derivatives.     

Deposition of hydroxyapatite and tricalcium phosphate coatings by suspension plasma spraying: Effects of torch speed

This research focuses on the deposition of hydroxyapatite (HA) and tricalcium phosphate (TCP) coatings produced by suspension plasma spraying (SPS) using in-house liquid feedstock suspensions. The work studied the effects of torch speed on the thickness, microstructure, and crystalline composition of the coatings. SPS allowed the deposition of HA and TCP coatings with thickness between 28 and 90?μm. The coatings presented lamellar microstructure with complex porosity between the splats. Micropores ranging from 0.2 to 6?μm and close mesopores, from 8 to 45?μm, had a spherical morphology and were homogenously distributed within the coatings. Water evaporation during SPS allowed the retention of pure and crystalline HA coatings. In contrast, the presence of water molecules led to the formation of HA as a secondary phase in the TCP coatings, which formed α-TCP as the major component due to the high temperature reached by the powder during deposition.