Development of immune and microbial environments is independently regulated in the mammary gland.

Breastfeeding is important for mammals, providing immunological and microbiological advantages to neonates, together with the nutritional supply from the mother. However, the mechanisms of this functional diversity in the mammary gland remain poorly characterized. Here, we show that, similar to the gastrointestinal tract, the mammary gland develops immune and microbial environments consisting of immunoglobulin A (IgA) and the microflora, respectively, both of which are important for protecting neonates and the mother from infectious diseases. The IgA production and microflora development are coordinated in the gastrointestinal tract but seem to be independently regulated in the mammary gland. In particular, the chemokine (C-C motif) ligand 28 and poly-Ig receptor, crucial molecules for the IgA production in milk, were expressed normally in germ-free lactating mice but were almost undetectable in postweaning mothers, regardless of the microflora presence. Our findings offer insights into potentially improving the quality of breastfeeding, using both immunological and microbiological approaches.

Analysis of the protective effects of a neuronal Cav2.1 calcium channel in brain injury.

We previously reported that rolling Nagoya mice carrying a mutation in the α1 subunit of the Cav2.1 channel protective from ischemia- and kainate-induced neuronal damage. However, the protective effect of this mutation and its relationship to brain injury recovery have not been examined. To examine the relationship between Cav2.1 channel function and brain injury, we induced cryogenic brain damage in homozygous rolling Nagoya (rol/rol), control wild-type (+/+), ω-agatoxin IVA-pretreated +/+ (ω-aga +/+), and ω-agatoxin IVA-post-treated +/+ (ω-aga-post-treated +/+) mice. We measured the lesion area, blood brain-barrier permeability and performed immunohistochemistry and western blot analysis. The lesions of rol/rol and ω-aga +/+ mice were significantly smaller than those observed in +/+ mice at both day 1 and day 7 after injury. Similar results were shown in blood-brain barrier permeability. We observed more reactive astrogliosis in +/+ mice than in rol/rol or ω-aga +/+ mice. rol/rol and ω-aga +/+ mice had fewer degenerating cells due to cryogenic injury than did +/+ mice at both day 1 and day 7. ω-Aga-post-treated +/+ mice 24h after injury were sacrificed on day 7. The lesions were smaller in ω-aga-post-treated +/+ mice than those in vehicle-treated +/+ mice. We also examined phosphorylated p38 (pp38) at the injured site. ω-Aga-post-treated +/+ mouse brain slices showed weak pp38 signal; vehicle-treated +/+ mouse brain slices were pp38-positive. These findings demonstrate that the mutant Cav2.1 channel exerts a protective effect against cryogenic brain injury in rolling Nagoya mice. Our results indicate that inhibitors of the Cav2.1-dependent p38 signaling cascade would be useful as therapeutic agents in the treatment of brain injury.

Proton pump inhibitor after endoscopic resection for esophageal squamous cell cancer: multicenter prospective randomized controlled trial.

BACKGROUND: Whether proton pump inhibitors (PPIs) relieve heartburn or precordial pain after endoscopic resection (ER) for esophageal squamous cell carcinoma (ESCC) remains unclear. The aim of this study was to investigate the efficacy of PPI therapy for these symptoms after ER for ESCC. METHODS: We conducted a multicenter prospective randomized controlled trial among 15 hospitals in Japan. In total, 229 patients with cT1a ESCC were randomly assigned to receive PPI therapy for 5 weeks after ER (the PPI group, n = 115) or follow-up without PPI therapy (the non-PPI group, n = 114). The primary end point was the incidence of gastroesophageal reflux disease (GERD)-like symptoms after ER from a self-reported questionnaire (Frequency Scale for Symptoms of GERD). Secondary end points were ulcer healing rate at 5 weeks, incidence of pain, improvement rate of symptoms in those who started PPI therapy because of GERD-like symptoms in the non-PPI group, and adverse events. RESULTS: No significant difference was observed in the incidence of GERD-like symptoms after ER between the non-PPI and PPI groups (30 % vs 34 %, respectively). No significant differences were observed in the ulcer healing rate at 5 weeks (84 % vs 85 %) and incidence of pain within 1 week (36 % vs 45 %). In nine of ten patients (90 %) who started PPI therapy because of GERD-like symptoms in the non-PPI group, PPI administration relieved GERD-like symptoms. No adverse events related to PPI administration were observed. CONCLUSION: PPI therapy is not efficacious in reducing symptoms and did not promote healing of ulcers in patients undergoing ER for ESCC.

High expression of N-acetylglucosaminyltransferase IVa promotes invasion of choriocarcinoma.

BACKGROUND: Gestational trophoblastic diseases (GTDs) are related to trophoblasts, and human chorionic gonadotropin (hCG) is secreted by GTDs as well as normal placentas. However, the asparagine-linked sugar chains on hCG contain abnormal biantennary structures in invasive mole and choriocarcinoma, but not normal pregnancy or hydatidiform mole. N-acetylglucosaminyltransferase-IV (GnT-IV) catalyses ß1,4-N-acetylglucosamine branching on asparagine-linked oligosaccharides, which are consistent with the abnormal sugar chain structures on hCG. METHODS: We investigated GnT-IVa expression in GTDs and placentas by immunohistochemistry, western blot, and RT-PCR. We assessed the effects of GnT-IVa knockdown in choriocarcinoma cells in vitro and in vivo. RESULTS: The GnT-IVa was highly expressed in trophoblasts of invasive mole and choriocarcinoma, and moderately in extravillous trophoblasts during the first trimester, but not in hydatidiform mole or other normal trophoblasts. The GnT-IVa knockdown in choriocarcinoma cells significantly reduced migration and invasive capacities, and suppressed cellular adhesion to extracellular matrix proteins. The extent of ß1,4-N-acetylglucosamine branching on ß1 integrin was greatly reduced by GnT-IVa knockdown, although the expression of ß1 integrin was not changed. In vivo studies further demonstrated that GnT-IVa knockdown suppressed tumour engraftment and growth. CONCLUSION: These findings suggest that GnT-IVa is involved in regulating invasion of choriocarcinoma through modifications of the oligosaccharide chains of ß1 integrin.

Improvement of a three-dimensional measurement system for the evaluation of foot edema.

BACKGROUND/AIMS: This study investigated the accuracy and usefulness of a newly improved three-dimensional measurement system for measuring the volume and circumference at the foot as well as at the calf and ankle. METHODS: Regarding the newly improved device, halogen light was projected from four directions instead of the conventional two directions. The circumference and volume were measured in the morning and evening with and without elastic stockings in 23 healthy subjects. RESULTS: The average circumference at the foot calculated using the 'average method', in which the circumference of the foot was measured in 10 places every 1 mm and the values were averaged, significantly increased in the evening compared with in the morning. When stockings were applied, the significant differences in the circumference or volume between the morning and evening disappeared at all sites of the leg. CONCLUSION: The newly improved three-dimensional measurement system incorporating the halogen light from four directions, in which the foot circumference was calculated using an 'average method', was reliable and useful for evaluating edema at the foot as well as at the calf and ankle. The beneficial effect of elastic stockings on edema prevention was observed at all sites of the leg.

Development of a device to determine the stiffness of elastic garments and bandages.

OBJECTIVE: To evaluate the reliability of a newly developed stiffness-determining device, composed of a leg mannequin and air-pack type analyser, for measuring the interface pressure. METHOD: The correlation of stiffness values obtained employing the Hohenstein method and this new method was investigated using 17 different brands of medical elastic compression stocking. RESULTS: A significant correlation in stiffness values using the two methods was obtained (P < 0.01). When this new method was applied to the bandages, the stiffness was significantly correlated with the initial pressure when assessing both short-stretch and long-stretch bandages. On the comparison of stiffness values between elastic stockings and bandages with the same initial pressure, the short-stretch bandages showed a predominantly higher value than long-stretch bandages and stockings (P < 0.01). CONCLUSION: The reliability of this new method, which can be easily applied to not only elastic stockings but also elastic bandages, was verified. In clinical practice, the compression pressure should be selected in consideration of the prospective stiffness.

Long-term outcomes of endoscopic submucosal dissection for colorectal epithelial neoplasms.

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) provides a high en bloc resection rate with less invasiveness than surgical resection for large or scarring gastrointestinal neoplasms. However, detailed outcomes in colorectal ESD are still lacking. The aim of our study was to elucidate short- and long-term outcomes of colorectal ESD. PATIENTS AND METHODS: 310 consecutive colorectal epithelial neoplasms (146 adenomas, 164 carcinomas), in 290 patients, which fulfilled our indication criteria and were treated with ESD between July 2000 and December 2008 were studied. ESD was done by three skilled endoscopists. As short-term outcomes, rates of en bloc resection, en bloc plus R0 resection, and major complications were analyzed. As long-term outcomes, disease-free and overall survival were assessed in 224 patients. RESULTS: Rates of en bloc resection and en bloc plus R0 resection were 90.3 % and 74.5 %, respectively. Eight patients underwent additional colectomy due to histopathologically proven possible node-positive cancer. Intraoperative perforations occurred with 14 lesions (4.5 %), which were treated successfully only by endoscopic clipping. Emergent surgery was needed for one case of postoperative perforation. Blood transfusion due to intraoperative massive bleeding was required in 1 case (0.3 %). Postoperative bleeding occurred with four lesions (1.3 %), and was endoscopically managed without blood transfusion. Local recurrence was detected in 4 lesions (4/202 patients, 2.0 %); resection had been piecemeal in all 4. During a median follow-up of 38.7 months (range 12.8 - 104.2), the 3- and 5-year overall/disease-specific survivals were 97.1/100 % and 95.3/100 %, respectively. CONCLUSIONS: Colorectal ESD showed favorable long-term outcomes. It may largely replace colectomy for node-negative colorectal epithelial neoplasia.

Comparison of stiffness and interface pressure during rest and exercise among various arm sleeves.

OBJECTIVES: To compare the interface pressure during rest and exercise among various kinds of arm sleeves. METHODS: The interface pressure underneath nine different arm sleeves was measured during 10 maximal opening and closing movements of fingers using a pressure transducer (Air Pack Type Analyser) in 16 healthy volunteers. Furthermore, in order to evaluate the characteristics of each arm sleeve, the extensibility, stiffness and thickness were determined in vitro by several apparatuses. RESULTS: There was a significant correlation between stiffness and extensibility. The stiffness was significantly correlated with the pressure difference between muscle contraction and relaxation during exercise. The higher the value of stiffness, the greater the pressure amplitude during exercise. CONCLUSION: Short-stretch arm sleeves characterized with a high level stiffness, including thick round- and flat-knitted arm sleeves, are more beneficial for the augmentation of muscle pumping than long-stretch arm sleeves, in the same way as short-stretch bandages or stockings applied to the leg.

Clinically significant micafungin resistance in Candida albicans involves modification of a glucan synthase catalytic subunit GSC1 (FKS1) allele followed by loss of heterozygosity.

OBJECTIVES: To determine the mechanism of intermediate- and high-level echinocandin resistance, resulting from heterozygous and homozygous mutations in GSC1 (FKS1), in both laboratory-generated and clinical isolates of Candida albicans. METHODS: The DNA sequences of the entire open reading frames of GSC1, GSL1 (FKS3) and RHO1, which may contribute to the beta-1,3-glucan synthase of a micafungin-susceptible strain and a resistant clinical isolate, were compared. A spontaneous heterozygous mutant isolated by selection for micafungin resistance, and a panel of laboratory-generated homozygous and heterozygous mutants that possessed combinations of the echinocandin-susceptible and -resistant alleles, or mutants with individual GSC1 alleles deleted, were used to compare levels of echinocandin resistance and inhibition of glucan synthase activity. RESULTS: DNA sequence analysis identified a mutation, S645P, in both alleles of GSC1 from the clinical isolate. GSL1 had two homozygous amino acid changes and five non-synonymous nucleotide polymorphisms due to allelic variation. The predicted amino acid sequence of Rho1p was conserved between strains. Reconstruction of the heterozygous (S645/S645F) and homozygous (S645F/S645F) mutation showed that the homozygous mutation conferred a higher level of micafungin resistance (4 mg/L) than the heterozygous mutation (1 mg/L). Exposure of the heterozygous mutant to micafungin resulted in a loss of heterozygosity. Kinetic analysis of beta-1,3-glucan synthase activity showed that the homozygous and heterozygous mutations gave echinocandin susceptibility profiles that correlated with their MIC values. CONCLUSIONS: A homozygous hot-spot mutation in GSC1, caused by mutation in one allele and then loss of heterozygosity, is required for high-level echinocandin resistance in C. albicans. Both alleles of GSC1 contribute equally and independently to beta-1,3-glucan synthase activity.

Predictors of postoperative stricture after esophageal endoscopic submucosal dissection for superficial squamous cell neoplasms.

BACKGROUND AND STUDY AIMS: Although endoscopic submucosal dissection (ESD) is becoming accepted as an established treatment for superficial esophageal squamous cell neoplasms, the risks for developing postoperative stricture have not been elucidated. PATIENTS AND METHODS: This was a retrospective study at a single institution. From January 2002 to October 2008, 65 patients with high-grade intraepithelial neoplasms (HGINs) or m2 carcinomas treated by ESD were enrolled. Predictors of postoperative stricture were investigated by comparing results from 11 patients who developed strictures with those from 54 patients who did not. RESULTS: Significant differences between the two groups were observed in longitudinal diameter (45.0 +/- 15.9 mm vs. 31.5 +/- 13.6 mm) and circumferential diameter (37.2 +/- 8.6 mm vs. 26.8 +/- 9.7 mm) of the resected specimens, and the proportion of extension to the whole circumference of the lumen (< 1 / 2/ > 1 / 2/ > 3 / 4 : 2 / 4 / 5 vs. 40 / 13 / 1), histologic depth (HGIN/m2 : 2 / 9 vs. 41 / 13), and procedure time (85.6 +/- 42.8 minutes vs. 53.3 +/- 30.1 minutes). Multivariate analysis revealed that circumferential extension of > 3 / 4 (odds ration [OR]: 44.2; 95 % confidence interval [CI]: 4.4 - 443.6) and histologic depth to m2 (OR: 14.2; 95 %CI: 2.7 - 74.2) are reliable risk factors. Subanalysis for each category by combinations of these risk factors revealed that patients with lesions in > 3 / 4 of the circumferential area were associated with a high rate of postoperative stricture. By contrast, patients with HGIN lesions in < 3 / 4 extension have no probability of postoperative strictures. Additionally, subanalysis of patients with m2 lesions in < 3 / 4 circumferential extension revealed that circumferential diameter can be a reliable predictor for postoperative stricture. CONCLUSIONS: Circumferential extension and histologic depth are the reliable risk factors for postoperative strictures. In combination with circumferential diameter, we can perform effective and appropriate preventive balloon dilatations after esophageal ESD.

A comparison of interface pressure and stiffness between elastic stockings and bandages.

OBJECTIVES: To compare the interface pressure during posture changes and exercise between elastic stockings and bandages. METHODS: Using a pressure transducer (air pack-type analyzer), the interface pressures associated with three different elastic stockings and three different elastic bandages were measured during supine resting, standing and exercise in 15 healthy volunteers. RESULTS: Short-stretch bandages showed a significantly higher static stiffness index value, which is defined as the pressure difference between lying and standing, than long-stretch bandages and short-stretch stockings (P < 0.001). Furthermore, short-stretch bandages showed a significantly greater pressure difference between muscle contraction and relaxation in both tip-toe and knee-bending exercises than long-stretch bandages and short-stretch stockings (P < 0.001). CONCLUSION: Short-stretch bandages can be expected to have more pronounced benefits for augmenting muscle pump than long-stretch bandages and short-stretch stockings.

Hypoalgesic behaviors of P/Q-type voltage-gated Ca2+ channel mutant mouse, rolling mouse Nagoya.

Rolling mouse Nagoya (tg(rol)) is a spontaneously occurring P/Q-type voltage-gated Ca2+ channel (VGCC) mutant mouse. A P/Q-type VGCC with the tg(rol) mutation has lower voltage sensitivity of activation, and mice with a homozygous genotype (tg(rol)/tg(rol)) but not with a heterozygous genotype (tg(rol)/+) show impaired motor coordination of the hind limbs. To investigate the roles of P/Q-type VGCC in pain sensing mechanisms, behavioral responses of adult tg(rol) mice to thermal, mechanical and chemical nociceptive stimuli were examined by the plantar, tail-flick, von Frey and formalin tests. The latency of the withdrawal response to thermal stimuli in the plantar or tail-flick tests was significantly longer in tg(rol)/tg(rol) mice than in tg(rol)/+ and wild-type (+/+) mice, and in tg(rol)/+ mice than in +/+ mice. The withdrawal response to mechanical stimuli in the von Frey test was lower in tg(rol)/tg(rol) mice than in +/+ mice. Although the licking time during the first 5 min after the formalin injection was similar among all of the three genotypes, that during 5-60 min was significantly shorter in tg(rol)/tg(rol) mice than in tg(rol)/+ and +/+ mice, and in tg(rol)/+ mice than in +/+ mice. Artificial inflammation induced by injection of complete Freund's adjuvant (CFA) into a hind paw significantly enhanced the withdrawal response recorded in the plantar and von Frey tests regardless of the mouse genotype. The CFA-enhanced response in the tg(rol)/tg(rol) mice was similar to the response in +/+ mice without the CFA injection. These results suggest that tg(rol) mutant mice show hypoalgesic responses caused by a lower sensitivity to nociceptive thermal, mechanical and chemical stimuli. It is concluded that the P/Q-type VGCC has a pro-nociceptive role and that the tg(rol) mutant mouse may be a useful tool to investigate the role of the P/Q-type VGCC in pain sensing mechanisms.

Technical feasibility of endoscopic submucosal dissection for early gastric cancer in patients taking anti-coagulants or anti-platelet agents.

BACKGROUND: Endoscopic submucosal dissection is a novel technique that is expected to be a curative treatment for early gastric cancers. Anti-coagulants and anti-platelet agents are widely used, especially in elderly patients, to prevent thromboembolic disease. However, the feasibility of endoscopic submucosal dissection for such patients has not been investigated. AIMS: To determine the feasibility of endoscopic submucosal dissection for patients using anti-coagulant and anti-platelet agents via retrospective investigation of clinical outcomes. METHODS: Of 408 patients with 444 early gastric cancers consecutively treated by endoscopic submucosal dissection from January 2000 to December 2007 in our hospital, 47 patients with 56 early gastric cancers were receiving anti-coagulants or anti-platelet agents. All patients were classified into groups for high and low risk of thromboembolism. In 44 low-risk patients, these agents were stopped for 1 week before and after treatment. Only three high-risk patients underwent intravenous heparin replacement during the cessation period. RESULTS: Comparison with other patients showed no significant differences in complete en-bloc resection (96.4%) or perforation (1.8%). Postoperative bleeding requiring endoscopic treatment occurred for six early gastric cancers (10.7%) in the anti-coagulant and anti-platelet group; this frequency was slightly higher than that observed for other patients (5.2%). The healing of endoscopic submucosal dissection ulcers was not delayed by anti-coagulant and anti-platelet treatment (91% in the scarring stage) when checked at the 8th week after endoscopic submucosal dissection. CONCLUSION: The clinical outcomes of endoscopic submucosal dissection for early gastric cancers in patients receiving anti-coagulants or anti-platelet agents indicated that endoscopic submucosal dissection for low-risk patients could be a reliable technique with equivalent efficacy and risk in comparison with that for other early gastric cancer patients.

Contributions of social context to inequality in dental caries: a multilevel analysis of Japanese 3-year-old children.

BACKGROUND: Community context as well as individual health behavior affects oral health status. However, the contribution of social context to dental caries among people in various regions remains unclear when individual health behavior is taken into account. OBJECTIVES: To determine the influence of community context on dmft among 3-year-old children. METHODS: After all Japanese municipalities (n = 2522) had been stratified into nine regions with three caries levels, 44 municipalities were randomly selected. Community health service workers were asked to collect information on sociodemographic characteristics, oral health-related behavior, and dental condition for 3-year-old children during community dental health check-ups. Community-related variables, including socioeconomic status, social support, and social cohesion, were obtained from census data. Multilevel analysis was used to determine the effects of social context and individual behavior on dental caries. RESULTS: A total of 3301 parents (79.9%) of 3-year-old children from 39 municipalities participated in our survey, and complete information was obtained from 3086 of them. Results of the analysis showed that 90.8% (P < 0.001) of variance in dmft occurred at the individual level and that 9.2% (P < 0.001) of the variance occurred at the community level. Individual-level variables explained only 6.6% of the individual level variance in dmft. Community-level variables explained 47.2% of the community level variance. CONCLUSIONS: There are statistically significant effects of social context on dmft in municipalities in Japan.

Overexpression of Candida albicans CDR1, CDR2, or MDR1 does not produce significant changes in echinocandin susceptibility.

The micafungin and caspofungin susceptibilities of Candida albicans laboratory and clinical isolates and of Saccharomyces cerevisiae strains stably hyperexpressing fungal ATP-binding cassette (ABC) or major facilitator superfamily (MFS) transporters involved in azole resistance were determined using three separate methods. Yeast strains hyperexpressing individual alleles of ABC transporters or an MFS transporter from C. albicans gave the expected resistance profiles for the azoles fluconazole, itraconazole, and voriconazole. The strains hyperexpressing CDR2 showed slightly decreased susceptibility to caspofungin in agar plate drug resistance assays, as previously reported, but increased susceptibility to micafungin compared with either the strains hyperexpressing CDR1 or the null parent deleted of seven ABC transporters. The strains hyperexpressing CDR1 showed slightly decreased susceptibility to micafungin in these assays. A C. albicans clinical isolate overexpressing both Cdr1p and Cdr2p relative to its azole-sensitive isogenic progenitor acquired resistance to azole drugs and showed reduced susceptibility to caspofungin and slightly increased susceptibility to micafungin in agar plate drug resistance assays. None of the strains showed significant resistance to micafungin or caspofungin in liquid microdilution susceptibility assays. The antifungal activities of micafungin and caspofungin were similar in agarose diffusion assays, although the shape and size of the caspofungin inhibitory zones were affected by medium composition. The assessment of micafungin and caspofungin potency is therefore assay dependent; the differences seen with agar plate drug resistance assays occur over narrow ranges of echinocandin concentrations and are not of clinical significance.

Bond strength and SEM observation of CO2 laser irradiated dentin, bonded with simplified-step adhesives.

This study investigated, mechanically and morphologically, whether the dentin surface irradiated by CO2 laser could be a possible adherent when bonded with simplified-step adhesives. Buccal enamel and cementum of extracted human premolars were removed to expose a flat dentin surface. The dentin surfaces were irradiated continuously with CO2 laser at 1.0 W. Before bonding with either a single-bottle adhesive (Single Bond) or a self-etching priming system (Mega Bond), the irradiated dentin surface was treated as follows: no treatment, NaHCO3 powder abrasion and wet-grinding with 600-grit SiC paper. The treated dentin surfaces were bonded to resin composite with either of the two adhesives. Non-irradiated dentin surfaces were also used as control. Resin bonded specimens were stored in water at 37 degrees C for 24 hours and subjected to microtensile bond test. Additionally, to observe the resin/irradiated dentin interface, resin-bonded specimens were similarly prepared, sectioned into slabs, embedded in epoxy resin, polished with diamond pastes, sputter coated Au-Pd and examined with scanning electron microscopy (SEM). After SEM observation, the specimens were further polished with diamond paste to remove the Au-Pd sputter-coat, immersed in HCL and NaOCl and finally observed by SEM again. In the presence of carbonized dentin, microtensile bond strength drastically decreased but recovered to the control value by removing the carbonized dentin layer visually with SiC paper for both adhesive systems. However, the laser-affected dentin that remained on the bonded interface was easily dissolved with NaOCl and HCl.

Chemosensitization of fluconazole resistance in Saccharomyces cerevisiae and pathogenic fungi by a D-octapeptide derivative.

Hyperexpression of the Saccharomyces cerevisiae multidrug ATP-binding cassette (ABC) transporter Pdr5p was driven by the pdr1-3 mutation in the Pdr1p transcriptional regulator in a strain (AD/PDR5(+)) with deletions of five other ABC-type multidrug efflux pumps. The strain had high-level fluconazole (FLC) resistance (MIC, 600 microg ml(-1)), and plasma membrane fractions showed oligomycin-sensitive ATPase activity up to fivefold higher than that shown by fractions from an isogenic PDR5-null mutant (FLC MIC, 0.94 microg ml(-1)). In vitro inhibition of the Pdr5p ATPase activity and chemosensitization of cells to FLC allowed the systematic screening of a 1.8-million-member designer D-octapeptide combinatorial library for surface-active Pdr5p antagonists with modest toxicity against yeast cells. Library deconvolution identified the 4-methoxy-2,3,6-trimethylbenzensulfonyl-substituted D-octapeptide KN20 as a potent Pdr5p ATPase inhibitor (concentration of drug causing 50% inhibition of enzyme activity [IC(50)], 4 microM) which chemosensitized AD/PDR5(+) to FLC, itraconazole, and ketoconazole. It also inhibited the ATPase activity of other ABC transporters, such as Candida albicans Cdr1p (IC(50), 30 microM) and Cdr2p (IC(50), 2 microM), and chemosensitized clinical isolates of pathogenic Candida species and S. cerevisiae strains that heterologously hyperexpressed either ABC-type multidrug efflux pumps, the C. albicans major facilitator superfamily-type drug transporter Ben(R)p, or the FLC drug target lanosterol 14 alpha-demethylase (Erg11p). Although KN20 also inhibited the S. cerevisiae plasma membrane proton pump Pma1p (IC(50), 1 microM), the peptide concentrations required for chemosensitization made yeast cells permeable to rhodamine 6G. KN20 therefore appears to indirectly chemosensitize cells to FLC by a nonlethal permeabilization of the fungal plasma membrane.

Parallel replacement of the oxygenator that is not transferring oxygen: the PRONTO procedure.

We present here a technique to replace a failed oxygenator by inserting a second oxygenator in parallel (PRONTO) within the cardiopulmonary bypass (CPB) circuit. Oxygenator failure is a potential hazard that may result in patient injury or death. Although failures are rare, safety surveys conducted over the last 25 years suggest that the incidence of oxygenator failures is on the rise. This emergency procedure may be easily applied to any standard CPB circuit with a few minor alterations. The technique is simple; it can be carried out rapidly. An important advantage of this technique is that it may be executed without interrupting blood flow to the patient, which may reduce the incidence of patient injury or death.

Functional expression of Candida albicans drug efflux pump Cdr1p in a Saccharomyces cerevisiae strain deficient in membrane transporters.

Analysis of the transport functions of individual Candida albicans plasma membrane drug efflux pumps is hampered by the multitude of endogenous transporters. We have stably expressed C. albicans Cdr1p, the major pump implicated in multiple-drug-resistance phenotypes, from the genomic PDR5 locus in a Saccharomyces cerevisiae mutant (AD1-8u(-)) from which seven major transporters of the ATP-binding cassette (ABC) family have been deleted. High-level expression of Cdr1p, under the control of the S. cerevisiae PDR5 promoter and driven by S. cerevisiae Pdr1p transcriptional regulator mutation pdr1-3, was demonstrated by increased levels of mRNA transcription, increased levels of nucleoside triphosphatase activity, and immunodetection in plasma membrane fractions. S. cerevisiae AD1-8u(-) was hypersensitive to azole antifungals (the MICs at which 80% of cells were inhibited [MIC(80)s] were 0.625 microg/ml for fluconazole, <0.016 microg/ml for ketoconazole, and <0.016 microg/ml for itraconazole), whereas the strain (AD1002) that overexpressed C. albicans Cdr1p was resistant to azoles (MIC(80)s of fluconazole, ketoconazole, and itraconazole, 30, 0.5, and 4 microg/ml, respectively). Drug resistance correlated with energy-dependent drug efflux. AD1002 demonstrated resistance to a variety of structurally unrelated chemicals which are potential drug pump substrates. The controlled overexpression of C. albicans Cdr1p in an S. cerevisiae background deficient in other pumps allows the functional analysis of pumping specificity and mechanisms of a major ABC transporter involved in drug efflux from an important human pathogen.