Mineralization of sulfonamides from wastewater using ozone-based systems.

Ozone, UV/ozone, ozone/persulfate (PS) and UV/ozone/PS systems were used to mineralize sulfonamides. Sulfadiazine (SDZ), sulfamerazine (SMR) and sulfamethazine (SMZ) were the target compounds. The novel contribution of this study is its determination of the effects of PS addition, sulfonamide structure, pH and salinity on sulfonamide mineralization in ozone-based systems. The mineralization rate of sulfonamides satisfied pseudo-first-order kinetics. The SMZ mineralization rate constant in ozone, UV/ozone, ozone/PS and UV/ozone/PS systems at pH 5 were 0.0058; 0.0101; 0.0069 and 0.0802 min-1, respectively, and those at pH 7 were 0.0075; 0.0116; 0.0083 and 0.0873 min-1, respectively. The increase in the number of methyl substituents in the heterocyclic group of SMZ and the corresponding increase in the steric hindrance of radical addition, reduced mineralization rates below those of SMR and SDZ. The addition of PS promoted sulfonamide mineralization in the ozone-based systems; conversely, salinity inhibited sulfonamide mineralization.

Proliferation modulates intestinal smooth muscle phenotype in vitro and in colitis in vivo.

Intestinal inflammation causes an increased intestinal wall thickness, in part, due to the proliferation of smooth muscle cells, which impairs the contractile phenotype elsewhere. To study this, cells from the circular muscle layer of the rat colon (CSMC) were isolated and studied, both in primary culture and after extended passage, using quantitative PCR, Western blot analysis, and immunocytochemistry. By 4 days in vitro, both mRNA and protein for the smooth muscle marker proteins α-smooth muscle actin, desmin, and SM22-α were reduced by >50%, and mRNA for cyclin D1 was increased threefold, evidence for modulation to a proliferative phenotype. Continued growth caused significant further decrease in expression, evidence that phenotypic loss in CSMC was proportional to the extent of proliferation. In CSMC isolated at day 2 of trinitrobenzene sulfonic acid-induced colitis, flow cytometry and Western blotting showed that these differentiated markers were reduced in mitotic CSMC, while similar to control in nonmitotic CSMC. By day 35 post-trinitrobenzene sulfonic acid, when inflammation has resolved, CSMC were hypertrophic, but, nonetheless, showed markedly decreased expression of smooth muscle protein markers per cell. In vitro, day 35 CSMC displayed an accelerated loss of phenotype and increased thymidine uptake in response to serum or PDGF-BB. Furthermore, carbachol-induced expression of phospho-AKT (a marker of cholinergic response) was lost from day 35 CSMC in vitro, while retained in control cells. Therefore, proliferation reduces the expression of smooth-muscle-specific markers in CSMC, possibly leading to altered contractility. However, inflammation-induced proliferation in vivo also causes lasting changes that include unexpected priming for an exaggerated response to proliferative stimuli. Identification of the molecular mechanisms of intestinal smooth muscle cell phenotypic modulation will be helpful in reducing the detrimental effects of inflammation.

Effectiveness of conventional, low-dose and intermittent oral isotretinoin in the treatment of acne: a randomized, controlled comparative study.

BACKGROUND: The efficacy of conventional isotretinoin treatment (0·5-1·0 mg kg⁻¹ daily for 16-32 weeks, reaching a cumulative dose of 120 mg kg⁻¹) for acne has been well established. To date, there are many reports regarding the efficacy of low-dose and intermittent isotretinoin treatment in patients with acne. Data comparing these three therapeutic regimens simultaneously, however, are unavailable. OBJECTIVES: To evaluate the clinical efficacy and tolerability of low-dose and intermittent isotretinoin regimens and to compare them directly with conventional isotretinoin treatment. METHODS: In this study, 60 patients with moderate acne were enrolled and randomized to receive either isotretinoin at 0·5-0·7 mg kg⁻¹ daily (group A), isotretinoin at 0·25-0·4 mg kg⁻¹ daily (group B) or isotretinoin at 0·5-0·7 mg kg⁻¹ daily for 1 week out of every 4 weeks (group C). The total period of drug administration was 6 weeks in group C, and 24 weeks in groups A and B. Evaluations included global acne grading system (GAGS) scores, lesion counts (inflammatory and noninflammatory), patient satisfaction and side-effects. A 1-year follow-up evaluation after the end of treatment was also performed. RESULTS: Differences in GAGS scores were statistically significant between groups A and C (P < 0·001) and groups B and C (P = 0·044). There was no significant difference between groups A and B. For the number of inflammatory lesions, there were statistically significant differences between groups B and C (P = 0·048) and groups C and A (P = 0·005). There was no significant difference between groups A and B. For the number of noninflammatory lesions, there were statistically significant differences between groups B and C (P = 0·046) and groups C and A (P=0·006). There was no significant difference between groups A and B. These results suggest that the conventional and low-dose regimens have similar efficacy. Intermittent treatment had less effect than either conventional or low-dose treatments. Patient satisfaction was highest in group B (3·76), followed by group C (3·31), then A (3·06), with statistically significant differences between groups A and B (P = 0·003) and groups B and C (P = 0·019) but no significant difference between groups A and C. This result suggests that the low-dose regimen is superior to other regimens (conventional or intermittent) in terms of patient satisfaction. Side-effects were more frequent with conventional treatment compared with low-dose and intermittent treatments. One year after the end of treatment, two of 16 patients relapsed in group A, three of 17 patients relapsed in group B, and nine of 16 patients relapsed in group C. CONCLUSIONS: Our study suggests that, when considering tolerability, efficacy and patient satisfaction, low-dose treatment is most suitable for patients with moderate acne.

[Efficacy of minimally invasive pulmonary surfactant administration in preterm infants with neonatal respiratory distress syndrome: a multicenter clinical trial].

Objective: To explore the feasibility and safety of minimally invasive surfactant administration (MISA) in preterm neonates with respiratory distress syndrome (NRDS). Methods: In this multicenter prospective randomized controlled trial, 92 preterm infants with gestation age ≤30 weeks and diagnosed with NRDS were enrolled in 8 level Ⅲ neonatal intensive care units (NICU) in Beijing-Tianjin-Hebei Region from 1(st) July 2017 to 31(st) December 2018. They were randomly assigned to minimally invasive surfactant administration (MISA) group or endotracheal intubation surfactant administration (EISA) group according to random number generated by computer. Infants in both groups received calf pulmonary surfactant preparation at a dose of 70-100 mg/kg. The data of demography, perinatal situation, medication administration, complications, clinical outcomes in the two groups were compared with Chi-square test, Student's t-test, Mann-Whitney U test or Fisher's exact test. Results: Among the 92 preterm infants, 53 were males, 39 were females; 47 were in the MISA group (25 males), and 45 were in the EISA group (28 males). The gestational age and birth weight were (29.5±1.2) weeks and (1 271±242) g in all patients, (29.5±1.4) weeks and (1 285±256) g in the MISA group, and (29.6±0.9) weeks and (1 255±227) g in the EISA group. The duration of surfactant infusion and the length of whole procedure in the MISA group were significantly longer than that in the EISA group (60 (18, 270) s vs. 50 (30, 60) s, Z=3.009, P=0.003; 90 (60, 300) s vs. 60 (44, 270) s, Z=3.365, P=0.001). For the outcomes, the incidence of hemodynamically significant patent ductus arteriosus (hsPDA) and bronchopulmonary dysplasia (BPD) were lower in the MISA group than in the EISA group (36% (17/47) vs. 67% (30/45), χ(2)=8.556, P=0.003; 26% (12/47) vs. 47% (21/45), χ(2)=4.464, P=0.035). Conclusions: Minimally invasive surfactant administration is applicable in preterm infants ≤30 weeks gestational age with NRDS. Although the length of whole procedure is longer than route endotracheal administration, the benefit of decreasing the incidences of hsPDA and BPD outweighs this demerit.

SDZ PSC 833, the cyclosporine A analogue and multidrug resistance modulator, activates ceramide synthesis and increases vinblastine sensitivity in drug-sensitive and drug-resistant cancer cells.

Resistance to chemotherapy is the major cause of cancer treatment failure. Insight into the mechanism of action of agents that modulate multidrug resistance (MDR) is instrumental for the design of more effective treatment modalities. Here we show, using KB-V-1 MDR human epidermoid carcinoma cells and [3H]palmitic acid as metabolic tracer, that the MDR modulator SDZ PSC 833 (PSC 833) activates ceramide synthesis. In a short time course experiment, ceramide was generated as early as 15 min (40% increase) after the addition of PSC 833 (5.0 microM), and by 3 h, [3H]ceramide was >3-fold that of control cells. A 24-h dose-response experiment showed that at 1.0 and 10 microM PSC 833, ceramide levels were 2.5- and 13.6-fold higher, respectively, than in untreated cells. Concomitant with the increase in cellular ceramide was a progressive decrease in cell survival, suggesting that ceramide elicited a cytotoxic response. Analysis of DNA in cells treated with PSC 833 showed oligonucleosomal DNA fragmentation, characteristic of apoptosis. The inclusion of fumonisin B1, a ceramide synthase inhibitor, blocked PSC 833-induced ceramide generation. Assessment of ceramide mass by TLC lipid charring confirmed that PSC 833 markedly enhanced ceramide synthesis, not only in KB-V-1 cells but also in wild-type KB-3-1 cells. The capacity of PSC 833 to reverse drug resistance was demonstrated with vinblastine. Whereas each agent at a concentration of 1.0 microM reduced cell survival by approximately 20%, when PSC 833 and vinblastine were coadministered, cell viability fell to zero. In parallel experiments measuring ceramide metabolism, it was shown that the PSC 833/vinblastine combination synergistically increased cellular ceramide levels. Vinblastine toxicity, also intensified by PSC 833 in wild-type KB-3-1 cells, was as well accompanied by enhanced ceramide formation. These data demonstrate that PSC 833 has mechanisms of action in addition to P-glycoprotein chemotherapy efflux pumping.

Intestinal smooth muscle phenotype determines enteric neuronal survival via GDNF expression.

Intestinal inflammation causes initial axonal degeneration and neuronal death, as well as the proliferation of intestinal smooth muscle cells (ISMC), but subsequent axonal outgrowth leads to re-innervation. We recently showed that expression of glial cell-derived neurotrophic factor (GDNF), the critical neurotrophin for the post-natal enteric nervous system (ENS) is upregulated in ISMC by inflammatory cytokines, leading us to explore the relationship between ISMC growth and GDNF expression. In co-cultures of myenteric neurons and ISMC, GDNF or fetal calf serum (FCS) was equally effective in supporting neuronal survival, with neurons forming extensive axonal networks among the ISMC. However, only GDNF was effective in low-density cultures where neurons lacked contact with ISMC. In early-passage cultures of colonic circular smooth muscle cells (CSMC), polymerase chain reaction (PCR) and western blotting showed that proliferation was associated with expression of GDNF, and the successful survival of neonatal neurons co-cultured on CSMC was blocked by vandetanib or siGDNF. In tri-nitrobenzene sulfonic acid (TNBS)-induced colitis, immunocytochemistry showed the selective expression of GDNF in proliferating CSMC, suggesting that smooth muscle proliferation supports the ENS in vivo as well as in vitro. However, high-passage CSMC expressed significantly less GDNF and failed to support neuronal survival, while expressing reduced amounts of smooth muscle marker proteins. We conclude that in the inflamed intestine, smooth muscle proliferation supports the ENS, and thus its own re-innervation, by expression of GDNF. In chronic inflammation, a compromised smooth muscle phenotype may lead to progressive neural damage. Intestinal stricture formation in human disease, such as inflammatory bowel disease (IBD), may be an endpoint of failure of this homeostatic mechanism.

Tamoxifen retards glycosphingolipid metabolism in human cancer cells.

In this study we provide evidence that tamoxifen, the widely used breast cancer drug, is a potent antagonist of glycolipid metabolism. When added to the medium of cultured multidrug resistant (MDR) KB-V-1 carcinoma cells, tamoxifen, at 5.0 microM, drastically lowered the levels of glucosylceramide (glc-cer), as evidenced by a reduction in glc-cer mass. In a similar fashion, in cultured human melanoma cells grown with [3H]galactose, tamoxifen inhibited formation of glc-cer by 44%, and retarded lactosylceramide and ganglioside formation by 50 and 35%, respectively. When glc-cer synthase of melanoma was assayed in cell-free incubations, the inclusion of tamoxifen, at a 1:10 molar ratio with ceramide, inhibited glc-cer synthesis by 50%. These results clearly reveal a new action of tamoxifen and thereby pose intriguing questions regarding mechanisms of action in the realm of estrogen receptor-independent modalities, including effects on MDR.

The multidrug resistance modulator SDZ PSC 833 is a potent activator of cellular ceramide formation.

In this study we demonstrate that the multidrug resistance (MDR) modulator PSC 833 is a potent agonist of ceramide metabolism. When added with [3H]serine or [3H]palmitic acid to the culture medium of MCF-7 cells, PSC 833, in a dose-responsive fashion (1-10 microM), increased the levels of [3H]ceramide as much as 16-fold over control. The actual increase in ceramide mass was verified by thin-layer chromatographic chars. Cellular sphingomyelin radioactivity did not decrease during treatment, indicating that PSC 833 does not elicit ceramide formation through a sphingomyelinase pathway. Inclusion of fumonisin B1, an inhibitor of ceramide synthase, blocked formation of ceramide by PSC 833. The results of cell proliferation assays demonstrated a clear correlation between PSC 833 elicitation of ceramide formation and increased cytotoxicity. The MDR modulator and chemical cousin of PSC 833, cyclosporin A, had little impact on cellular ceramide formation. At a concentration of 2.5 microM, cyclosporin A and PSC 833 treatment increased ceramide formation by 20% and 7.5-fold, respectively. These results reveal a new action of PSC 833 which may contribute to its potency as a drug resistance modulator.

Modification of ceramide metabolism increases cancer cell sensitivity to cytotoxics.

In the preceding report we demonstrated that MCF-7-AdrR cells (adriamycin resistant) were insensitive to ceramide, whereas MCF-7 wild-type cells were sensitive. It was also shown that the drug resistant cells had an increased capacity to convert ceramide to glucosylceramide. Here we demonstrate that blocking the conversion of ceramide to glucosylceramide increases MCF-7-AdrR cell sensitivity to ceramide as well as to antitumor agents. Treatment of MCF-7 cells with adriamycin elicited a 5-fold increase in ceramide, and caused oligonucleosomal fragmentation, characteristic to apoptosis. Under similar treatment conditions, ceramide was not generated in MCF-7-AdrR cells. In MCF-7-AdrR cells neither C6-ceramide nor tamoxifen was cytotoxic; however, the addition of tamoxifen to the C6-ceramide treatment regimen reduced cell viability to 42% and elicited apoptosis. Treatment of MCF-7-AdrR cells with Adriamycin promoted an increase in ceramide only if tamoxifen was present, in which case ceramide increased 7-fold, and cell viability decreased to 50%. The employment of another agent, RU486 (Mifepristone), which blocks ceramide glycosylation, increased MCF-7-AdrR cell sensitivity to adriamycin in a dose-dependent manner. Our data show that agents that block ceramide glycosylation potentiate cellular sensitivity to ceramide and to chemotherapeutic drugs, and suggest that the ceramide metabolic pathway is an important target for anticancer drug development.

Ceramide toxicity and metabolism differ in wild-type and multidrug-resistant cancer cells.

Previously we demonstrated that multidrug-resistant (MDR) cancer cells have elevated levels of a glycosylated form of ceramide, glucosylceramide. Here we compared ceramide metabolism and ceramide toxicity in MCF-7 and in adriamycin-resistant (MCF-7-AdrR) human breast cancer cells. MCF-7-AdrR cells were resistant to C6-ceramide (1-10 microM); however, in MCF-7 cells treated with C6-ceramide, viability dropped sharply. Ceramide, when supplemented, was not metabolized by MCF-7 cells. In contrast, ceramide was efficiently converted to glucosylceramide by MCF-7-AdrR cells. Analysis of extracellular [3H]ceramide in radiolabeled cells showed that MCF-7-AdrR cells do not have an enhanced capacity to efflux ceramide compared with MCF-7 cells. Triphenylethylene anti-estrogens, known modulators of drug resistance, were effective inhibitors of ceramide conversion to glucosylceramide, suggesting that blocking ceramide metabolism plays a role in chemosensitization. The anti-progestine, RU486, also blocked glucosylceramide synthesis in cells; however, LY117018, a raloxifene analog, was without influence. We propose that an enhanced capacity to glycosylate ceramide as evidenced in MCF-7-AdrR cells, is a molecular determinant of drug resistance, particularly as regards resistance to ceramide-enhancing agents such as anthracyclines, ionizing radiation, and tumor necrosis factor-alpha.

Taxol-induced ceramide generation and apoptosis in human breast cancer cells.

PURPOSE: Taxol has emerged as a valuable antimitotic chemotherapeutic agent, particularly in advanced breast and ovarian cancers. Although much is known about cytotoxic mechanisms, the effectiveness of Taxol cannot be solely explained by microtubular interaction. This study was undertaken to determine whether ceramide generation plays a role in Taxol-induced apoptosis. METHODS: Hormone-independent MDA-MB-468 and hormone-dependent MCF-7 breast cancer cell lines were employed, and ceramide metabolism was characterized using [3H]palmitic acid as lipid precursor. RESULTS: Exposure of cells to Taxol resulted in enhanced formation of [3H]ceramide. Ceramide increased nearly 2-fold in MDA-MB-468 cells exposed to 50 nM Taxol, and more than 2.5-fold in MCF-7 cells exposed to 1.0 microM Taxol. These concentrations mirrored the EC50 (amount of drug eliciting 50% cell kill) for Taxol in the two cell lines. Use of cell-permeable C6-ceramide as a medium supplement revealed that MDA-MB-468 cells were 20-fold more sensitive to ceramide than MCF-7 cells (P < 0.001). Ceramide was generated as early as 6 h after exposure to Taxol in MDA-MB-468 cells, whereas the earliest signs of apoptosis were detected 12 h after treatment, and by 24 h the apoptotic index was six times that of untreated cells. Both fumonisin B1, a ceramide synthase inhibitor, and L-cycloserine, a serine palmitoyltransferase inhibitor, blocked Taxol-induced ceramide generation, whilst sphingomyelin levels remained unchanged, indicating a de novo pathway of ceramide formation. L-Cycloserine reduced Taxol-induced apoptosis by 30% in MDA-MB-468 cells and totally blocked Taxol-induced apoptosis in MCF-7 cells. CONCLUSIONS: These results suggest that Taxol-induced apoptosis is, in part, attributable to ceramide and sphingoid bases. This is of relevance to drug mechanism studies, as ceramide is a known messenger of apoptosis. Clinical use of Taxol with ceramide-enhancing agents may maximize cytotoxic potential.

Glucosylceramide: a marker for multiple-drug resistant cancers.

BACKGROUND: Multiple-drug resistance (MDR) is a major reason for chemotherapy failure. Herein we describe glucosylceramide, a new marker for MDR. METHODS: Cellular lipids were analyzed in three human MDR cancer cell lines and their drug-sensitive counterparts. Analysis of glucosylceramide was also performed in six melanoma specimens and one breast tumor specimen obtained from patients who had undergone chemotherapy. Glucosylceramide, analyzed by mass and by cellular utilization of radiolabeled precursor ([3Hpalmitic acid), was isolated by lipid extraction techniques and resolved from other components by thin-layer chromatography. RESULTS: Glucosylceramide was present consistently in all MDR cell lines and was absent, or present only at very low levels, in the corresponding drug-sensitive cells. Examination of human tumor specimens documented presence of the marker in all patients who had failed chemotherapy, and absence of the marker in each of the patients with known clinical response to chemotherapy. The response to chemotherapy was followed for a median of 8 months in melanoma patients and for 22 months in the breast cancer patient. CONCLUSION: These findings suggest that glucosylceramide may hold clinical significance for the early identification of drug-resistant tumors.

Effect of a new infrared light device (1100-1800 nm) on facial lifting.

Laser skin resurfacing procedures can be classed into two categories - invasive and non-invasive. The last several decades have witnessed a host of advancements in ablative laser therapy and other ablative modalities for the rejuvenation of skin, including the CO(2) laser, the erbium : yttrium aluminum garnet laser, chemical peels, and dermabrasion. Despite the excellent results that can result from the practice of these techniques by experienced surgeons, the invasive nature of these devices is associated with inherent risks and patient discomfort. Therefore, much of the focus has been on non-ablative lasers and intense-pulsed light devices. We evaluated the efficacy and safety of treatment with the new infrared light device (1100-1800 nm), Titan, and assessed the degree of improvement associated with two-time laser treatments, as compared to one-time laser treatment.

Solvent screening for a hard-to-dissolve molecular crystal.

Materials with a high-degree of inter- and intra-molecular hydrogen bonding generally have limited solubility in conventional organic solvents. This presents a problem for the dissolution, manipulation and purification of these materials. Using a state-of-the-art density-functional-theory based quantum chemical solvation model we systematically evaluated solvents for a known hydrogen-bonded molecular crystal. This, coupled with direct solubility measurements, uncovered a class of ionic liquids involving fluoride anions that possess more than two orders of magnitude higher solvation power as compared with the best conventional solvents. The crystal structure of one such ionic liquid, determined by X-ray diffraction spectroscopy, indicates that F- ions are stabilized through H-bonded chains with water. The presence of coordinating water in such ionic liquids seems to facilitate the dissolution process by keeping the chemical activity of the F- ions in check.

[Cold dysmenorrhea with blood stagnation treated with zhuyu wengong decoction].

Sixty-six women with stagnant blood and cold dysmenorrhea were treated with Zhuyu Wengong Decoction (ZWD). The results showed that 47 of them were cured, 13 improved, the total effective rate was 90.9%. Before treatment, the value of amplitude and the volume of blood flow in the left pelvic cavity with blood flow graph was very lower in the dysmenorrhea patients than those in the normal women (P less than 0.01), while the number of amplitude difference between the left and the right pelvic cavity being over 30% and of abnormal wave was higher in the patients than that in the normal women (P less than 0.01). After treatment, the value of amplitude and the volume of blood flow in the left pelvic cavity had a marked increase (P less than 0.01). These data suggested that blood circulation in the pelvic cavity took a turn for the better after the treatment. The results in animal experiment also showed that ZWD had strongly suppressive effect on the automatic action of uterine muscle of rats in vitro and of rabbits in vivo. The suppressive rates were 30.75% and 20% respectively, and the contractive range was at a lower level. The decoction also had strong suppressive effect on the contract induced by MPGF2 alpha, suppressive rate decreased to 24.4% and 34.75% respectively in contrast to the group which patients had not taken this decoction. The results in this study also proved that ZWD could improve the reduction of blood flow volume induced by MPGF2 alpha and had analgesic effect on dysmenorrhea model of rats induced by oxytocin.

Ceramide glycosylation potentiates cellular multidrug resistance.

Ceramide glycosylation, through glucosylceramide synthase (GCS), allows cellular escape from ceramide-induced programmed cell death. This glycosylation event confers cancer cell resistance to cytotoxic anticancer agents [Liu, Y. Y., Han, T. Y., Giuliano, A. E., and M. C. Cabot. (1999) J. Biol. Chem. 274, 1140-1146]. We previously found that glucosylceramide, the glycosylated form of ceramide, accumulates in adriamycin-resistant breast carcinoma cells, in vinblastine-resistant epithelioid carcinoma cells, and in tumor specimens from patients showing poor response to chemotherapy. Here we show that multidrug resistance can be increased over baseline and then totally reversed in human breast cancer cells by GCS gene targeting. In adriamycin-resistant MCF-7-AdrR cells, transfection of GCS upgraded multidrug resistance, whereas transfection of GCS antisense markedly restored cellular sensitivity to anthracyclines, Vinca alkaloids, taxanes, and other anticancer drugs. Sensitivity to the various drugs by GCS antisense transfection increased 7- to 240-fold and was consistent with the resumption of ceramide-caspase-apoptotic signaling. GCS targeting had little influence on cellular sensitivity to either 5-FU or cisplatin, nor did it modify P-glycoprotein expression or rhodamine-123 efflux. GCS antisense transfection did enhance rhodamine-123 uptake compared with parent MCF-7-AdrR cells. This study reveals that GCS is a novel mechanism of multidrug resistance and positions GCS antisense as an innovative force to overcome multidrug resistance in cancer chemotherapy.