Minocycline suppresses lipogenesis via inhibition of p300 histone acetyltransferase activity in human SZ95 sebocytes.

BACKGROUND: Minocycline is a second-generation tetracycline drug, which is widely used to treat diverse infectious and inflammatory diseases such as acne vulgaris. The effects of minocycline on acne vulgaris have been mainly attributed to its anti-inflammatory effect; however, its sebum-regulating effect and the relevance to epigenetic regulation in human sebaceous glands remain uninvestigated. OBJECTIVES: To identify the potential underlying epigenetic mechanism of sebum-inhibitory effects of minocycline in human SZ95 sebocytes. METHODS: The quantity of lipid droplets and the expression of key lipogenic genes were analysed in minocycline-treated SZ95 sebocytes. To examine whether the sebum-inhibitory effects of minocycline are relevant to histone acetylation, we analysed the effects of minocycline on p300 HAT and total HDAC activity. To elucidate the functional implication of p300 HAT inhibition by minocycline in sebocytes, we assessed the effect of p300 knockdown, inhibition and overexpression on lipid accumulation in SZ95 sebocytes. RESULTS: Minocycline suppressed the insulin and liver X receptor agonist-induced lipid accumulation and the expression of the key lipogenic transcription factor sterol regulatory element-binding protein 1 (SREBP1) and its downstream genes, fatty acid synthase (FAS) and acetyl-CoA carboxylase α (ACCα). Minocycline inhibited p300 HAT activity in a concentration-dependent manner, but demonstrated no effect on global HDAC activity, resulting in a significant decrease in histone acetylation. Downregulation of p300 by knockdown or inhibition significantly suppressed SREBP1 expression, histone acetylation and lipid accumulation, whereas p300 overexpression enhanced these effects. Moreover, p300 overexpression rescued minocycline-inhibited SREBP1 expression and lipid synthesis. CONCLUSIONS: Our findings revealed a novel sebum-regulating effect of minocycline. Moreover, as p300 HAT is a key epigenetic regulator of sebaceous lipogenesis, its inhibitors could be used for the treatment of acne vulgaris.

Evaluation of trabecular bone score in patients with a distal radius fracture.

We compared bone mineral density (BMD) and trabecular bone score (TBS) in postmenopausal women with a distal radius fracture older than 50 years with controls. Total hip BMD was significantly different, but TBS was not different between two groups, suggesting TBS does not reflect microarchitectural changes of the distal radius. INTRODUCTION: The purpose of this study was to determine whether trabecular bone score (TBS) has additive value for discriminating distal radius fracture (DRF) independent of BMD. METHODS: We compared BMD and TBS in 258 postmenopausal women with a DRF older than 50 years of age with age- and body mass index (BMI)-matched controls who had no history of osteoporotic fracture. BMD was measured at the lumbar spine and hip using dual energy X-ray absorptiometry scans (GE Lunar Prodigy). TBS was calculated on the same spine image. A multivariate logistic regression analysis was used to analyze the odds ratio (OR) for the occurrence of DRF using age, BMI, lumbar spine BMD, total hip BMD, and TBS. RESULTS: Patients with a DRF had significantly lower BMDs at hip (neck, trochanter and total) than those of controls: 0.752 ± 0.097, 0.622 ± 0.089, and 0.801 ± 0.099 in patients and 0.779 ± 0.092, 0.648 ± 0.089, 0.826 ± 0.101 in controls. However, lumbar spine BMD and TBS were not significantly different between the groups (p = 0.400 and 0.864, respectively). The multivariate analysis indicated that only total hip BMD was significantly associated with the occurrence of DRF (OR, 10.231; 95 % confidence interval, 1.724-60.702; p = 0.010). CONCLUSIONS: TBS was not different between women with a DRF and those without a history of osteoporotic fracture, suggesting that TBS measured at the lumbar spine does not reflect early microarchitectural changes of the distal radius. Only total hip BMD is associated with the risk of DRF in Korean women.

Effect of dietary supplementation of bacteriophage on performance, egg quality and caecal bacterial populations in laying hens.

1. Bacteriophages (BP) have gained increasing attention as a treatment of bacterial infection for animals. However, the data pertaining to dietary application of BP for laying hens have been limited. 2. This study aimed to investigate the effect of dietary BP on laying performance, egg quality and caecal bacterial populations in laying hens. 3. The dietary BP used in this experiment was a mixture of individual BP targeting Salmonella gallinarum, Salmonella pullorum, Salmonella typhimurium, Salmonella enteritidis, Salmonella derby and Staphylococcus aureus. 4. A total of 360 Hy-Line Brown laying hens of 32 weeks of age were allotted to one of three dietary treatments with 6 replicates in a completely randomised design. The basal diet was prepared, and 0.4 or 0.8 g/kg BP mixture was supplemented to the basal diet. Diets were fed to hens for 8 weeks. 5. Laying performance and egg quality were not affected by dietary treatments. As inclusion levels of BP mixture in diets were increased, the DNA copy numbers for Salmonella spp. in the caecal contents decreased linearly, whereas the DNA copy numbers for Escherichia coli in the caecal contents increased linearly. 6. Results indicate that dietary supplementation of BP mixture decreases the target Salmonella spp. populations but increases Escherichia coli populations in the gastrointestinal tract of laying hens with little impact on laying performance and egg quality.

Is elective nodal irradiation beneficial in patients with pathologically negative lymph nodes after neoadjuvant chemotherapy and breast-conserving surgery for clinical stage II-III breast cancer? A multicentre retrospective study (KROG 12-05).

BACKGROUND: To evaluate the effects of elective nodal irradiation (ENI) in clinical stage II-III breast cancer patients with pathologically negative lymph nodes (LNs) (ypN0) after neoadjuvant chemotherapy (NAC) followed by breast-conserving surgery (BCS) and radiotherapy (RT). METHODS: We retrospectively analysed 260 patients with ypN0 who received NAC followed by BCS and RT. Elective nodal irradiation was delivered to 136 (52.3%) patients. The effects of ENI on survival outcomes were evaluated. RESULTS: After a median follow-up period of 66.2 months (range, 15.6-127.4 months), 26 patients (10.0%) developed disease recurrence. The 5-year locoregional recurrence-free survival and disease-free survival (DFS) for all patients were 95.5% and 90.5%, respectively. Pathologic T classification (0-is vs 1 vs 2-4) and the number of LNs sampled (<13 vs ≥13) were associated with DFS (P=0.0086 and 0.0012, respectively). There was no significant difference in survival outcomes according to ENI. Elective nodal irradiation also did not affect survival outcomes in any of the subgroups according to pathologic T classification or the number of LNs sampled. CONCLUSIONS: ENI may be omitted in patients with ypN0 breast cancer after NAC and BCS. But until the results of the randomised trials are available, patients should be put on these trials.

Stage IE/IIE extranodal NK/T-cell lymphoma arising in the nasal cavity: analysis of CT findings and their prognostic value.

AIM: To investigate the computed tomography (CT) findings in patients with stage IE/IIE extranodal natural killer/T-cell lymphoma (ENKTL) arising in the nasal cavity and to evaluate whether imaging findings revealed by CT have prognostic value. MATERIALS AND METHODS: The CT findings of 62 patients diagnosed with IE/IIE ENKTL arising in the nasal cavity were retrospectively reviewed. Imaging findings were investigated, and evaluated imaging findings were analysed for the prognostic value of overall survival (OS) and disease-free survival (DFS). RESULTS: Of the 62 patients, 21 (34%) presented with a superficial infiltrative, 38 (61%) with a mass forming, and three (5%) with a combined pattern. Of all imaging findings, local invasiveness (n = 26, 42%), including bony destruction, erosion, or soft-tissue involvement, was the only independent prognostic factor for OS [p = 0.008; hazard ratio (HR): 3.85; 95% confidence intervals (CI): 1.42-10.44] and DFS (p = 0.001; HR: 4.25; 95% CI: 1.72-10.47). In a subgroup analysis of 36 cases with no local invasiveness, a superficial infiltrative pattern in one nasal cavity was a positive prognostic factor for OS (p = 0.028) and DFS (p = 0.008). CONCLUSION: Imaging findings at CT provided clinically useful predictions for treatment outcomes. Local invasiveness revealed by CT findings was a strong prognostic factor for poor OS and DFS. In addition, in patients with no local invasiveness, a superficial infiltrative pattern in one nasal cavity predicted favourable OS and DFS.

Pharmacology and Ethnomedicinal Potential of Selected Plants Species from Apiaceae (Umbelliferae).

BACKGROUND: The Apiaceae or Umbelliferae is one of the largest families in terms of species representation in the plant kingdom. It is also a prominent family in the field of phytochemicals and pharmacology. The family is also quite prominent in the production of spices and condiments and food supplements in nutrition, aside from the potential of species in the family to induce apoptotic, antimicrobial, antitumor, and hepatoprotective activities. OBJECTIVE: This work presents a detailed structural elucidation and functional aspects of phytochemicals from the Apiaceae or Umbelliferae family. METHODS: Furthermore, the application of members of this family in traditional and modern pharmacology is emphasized. This review also highlights the linkage of phytochemicals used in the conventional system of medication for the development of novel therapeutics through a chain of pre-clinical and clinical trials. CONCLUSION: This study may represent a valuable step ahead in the clinical development of natural drugs for curing several ailments, including respiratory and virus-related diseases.

Effects of silver nanoparticles on biological nitrogen removal processes.

The effects of silver (Ag) nanoparticles (NPs) on activated sludge in a biological nitrogen removal (BNR) process were investigated under aerobic and anoxic conditions. We show that nitrification was more vulnerable to Ag NPs exposure than denitrification at the same Ag NPs concentration. In continuous operation of the BNR process, a higher inhibitory effect on nitrification was attributed to a smaller size of Ag NPs. About 70-90% of the Ag NPs supplied were embedded in the sludge matrix but 10-30% of the Ag NPs remained in the supernatant. This indicates that significant amounts of Ag NPs could be discharged from wastewater treatment plants and potentially impact on aquatic ecosystems.

Minimal alterations in T-type calcium channel gating markedly modify physiological firing dynamics.

T-type calcium channel isoforms expressed in heterologous systems demonstrate marked differences in the biophysical properties of the resulting calcium currents. Such heterogeneity in gating behaviour not only reflects structural differences but is also observed following the regulation of channel activity by a number of ligands. However, the physiological impact of these differences in gating parameters of the T channels has never been evaluated in situ where the unique interplay between T-type calcium and other intrinsic currents is conserved, and T channel activation can be triggered by synaptic stimulation. Here, using the dynamic clamp technique, artificial T conductances were re-incorporated in thalamic neurons devoid of endogenous T currents to dissect the physiological role of the T current gating diversity on neuronal excitability. We demonstrate that the specific kinetics of the T currents in thalamocortical and nucleus reticularis thalami neurons determine the characteristic firing patterns of these neurons. We show that subtle modifications in T channel gating that are at the limit of the resolution achieved in classical biophysical studies in heterologous expression systems have profound consequences for synaptically evoked firing dynamics in native neurons. Moreover, we demonstrate that the biophysical properties of the T current in the voltage region corresponding to the foot of the activation and inactivation curves drastically condition physiologically evoked burst firing with a high degree of synaptic input specificity.

Xylitol production from a mutant strain of Candida tropicalis.

AIMS: To characterize the kinetics of growth, sugar uptake and xylitol production in batch and fed-batch cultures for a xylitol assimilation-deficient strain of Candida tropicalis isolated via chemical mutagenesis. METHODS AND RESULTS: Chemical mutagenesis using nitrosoguanidine led to the isolation of the xylitol-assimilation deficient strain C. tropicalis SS2. Shake-flask fermentations with this mutant showed a sixfold higher xylitol yield than the parent strain in medium containing 25 g l⁻¹ glucose and 25 g l⁻¹ xylose. With 20 g l⁻¹ glycerol, replacing glucose for cell growth, and various concentrations of xylose, the studies indicated that the mutant strain resulted in xylitol yields from xylose close to theoretical. Under fully aerobic conditions, fed-batch fermentation with repeated addition of glycerol and xylose resulted in 3.3 g l⁻¹ h⁻¹ xylitol volumetric productivity with the final concentration of 220 g l⁻¹ and overall yield of 0.93 g g⁻¹ xylitol. CONCLUSIONS: The xylitol assimilation-deficient mutant isolated in this study showed the potential for high xylitol yield and volumetric productivity under aerobic conditions. In the evaluation of glycerol as an alternative low-cost nonfermentable carbon source, high biomass and xylitol yields under aerobic conditions were achieved; however, the increase in initial xylose concentrations resulted in a reduction in biomass yield based on glycerol consumption. This may be a consequence of the role of an active transport system in the yeast requiring increasing energy for xylose uptake and possible xylitol secretion, with little or no energy available from xylose metabolism. SIGNIFICANCE AND IMPACT OF THE STUDY: The study confirms the advantage of using a xylitol assimilation-deficient yeast under aerobic conditions for xylitol production with glycerol as a primary carbon source. It illustrates the potential of using the xylose stream in a biomass-based bio-refinery for the production of xylitol with further cost reductions resulting from using glycerol for yeast growth and energy production.

Application of PTFE membrane for ammonia removal in a membrane contactor.

The feasibility of a membrane contactor system for ammonia removal was studied. The mass transfer coefficient was used to quantitatively compare the effect of various operation conditions on ammonia removal efficiency. Effective removal of ammonia was possible with a Polytetrafluoroethylene (PTFE) membrane contactor system at all tested conditions. Among the various operation parameters, contact time and solution pH showed significant effect on the ammonia removal mechanism. The overall ammonia removal rate was not affected by influent suspended solution concentration unlike other pressure driven membrane filtration processes. Also the osmotic distillation phenomena which deteriorate the mass transfer efficiency can be minimized by preheating of influent wastewater. A membrane contactor system can be a possible alternative to treat high strength nitrogen wastewater by optimizing operation conditions such as stripping solution flow rate, influent wastewater temperature, and influent pH.

Lactobacillus intestinalis YT2 restores the gut microbiota and improves menopausal symptoms in ovariectomized rats.

There are many studies focusing on the alleviation of menopausal symptoms; however, little is known about the role of gut microorganisms in menopausal symptoms. Ovariectomized (OVX) rats were administered a novel strain (YT2) of Lactobacillus intestinalis (a species with significantly reduced abundance in OVX rats) and the potential probiotic effect on the improvement of menopausal symptoms was evaluated. Of note, the gut microbial composition completely shifted after ovariectomy in rats. Treatment with L. intestinalis YT2 significantly alleviated menopausal symptoms, such as increased fat mass, decreased bone mineral density, increased pain sensitivity, depression-like behaviour, and cognitive impairment. Additionally, the administration of L. intestinalis YT2 restored the intestinal microbial composition, including an increased Firmicutes/Bacteroides ratio. L. intestinalis YT2 also promoted gut barrier integrity by increasing the mRNA levels of tight junction-related markers. In conclusion, L. intestinalis YT2 treatment alleviated menopausal symptoms via the modulation of the gut microbiota. Importantly, these results suggest that L. intestinalis YT2 should be considered as a therapeutic probiotic agent for menopausal women.

Platelet-mediated cytotoxicity. Role of antibody and C3, and localization of the cytotoxic system in membranes.

Platelets are one of several cell types capable of mediating antibody-dependent cellular cytotoxicity. We have developed a plasma-free system in which washed mouse platelets lyse washed antibody and complement-sensitized SRBC targets in the presence of EDTA. The dose-response curve is concave to the abscissa, indicating that lysis is a one-hit reaction. Determination of the actual number of platelets required to lyse a target shows that each platelet could lyse a single target. A limited degree of lysis is observed when platelets are incubated with SRBC sensitized with monoclonal IgG2a alone, but no lysis occurs with SRBC bearing comparable amounts of other isotypes. In the presence of C1 through C3, but not C1 through C2, efficient lysis is triggered by complement-fixing monoclonal IgG2a, IgG2b, and IgG3. In contrast, IgM and non-complement-fixing IgG1 and IgE are inactive. To achieve efficient lysis, it appears that platelets require both target cell-bound antibody and C3 fragments in close proximity. It is unlikely that proteases, pore-forming proteins, or toxic oxygen metabolites are involved in platelet-mediated lysis. Freezing and thawing of platelets, sonication, or sonication followed by hypotonic shock causes severe depletion of cytoplasmic and granular contents, as shown by electron microscopy and marker assays. However, the membrane fraction of these preparations retains cytolytic activity. When platelets are treated with trypsin or heated, lytic activity is eliminated, indicating that at least one component of this system is protein. These findings, as well as the fact that platelets do not lyse unsensitized innocent bystander SRBC, suggest that the complete cytotoxic system of platelets capable of specific recognition and lysis resides in their membranes.

Interactions of the complement system with endotoxic lipopolysaccharide: consumption of each of the six terminal complement components.

Large amounts of each C'3, C'5, C'6, C'7, C'8, and C'9 were consumed when guinea pig serum was incubated with endotoxic lipopolysaccharide, zymosan, or preformed immune complexes. Since these C' components subserve several of the biological activities which follow the injection of endotoxins into experimental animals, these experiments support the hypothesis that certain biological effects induced by endotoxins may be mediated via the C' system, and may account for some of the known similarity in the reactivities evoked by endotoxins and immune complexes in vivo.

A requirement for membrane-associated phospholipase A2 in platelet cytotoxicity activated by receptors for immunoglobulin G and complement.

Platelets are potent antibody- and complement-dependent cytotoxic effector cells. We showed previously that a single platelet can lyse a target cell sensitized with immunoglobulin G (IgG) and complement components up to C3 (C integral of 3b denotes the target cell-bound fragment of complement up to C3; the precise nature of the bound C3 fragment has not been established), and that the complete cytotoxic system capable of specific recognition and lysis resides in platelet membranes. To define the components of platelet membranes required for cytotoxicity, a set of inhibitors of phospholipase A2 (PLA2) that act by different chemical mechanisms was tested. The lytic reaction is blocked at appropriate concentrations of bromophenacylbromide, mepacrine, and manoalide. When platelets are treated with bromophenacylbromide, inhibition of cytolytic activity and that of PLA2 enzymatic activity occur in parallel. Platelets release arachidonate when incubated with target cells bearing IgG and C integral of 3b, confirming that Fc gamma R and complement receptor trigger both PLA2 action and efficient lysis. Inhibition by thimerosal of a reverse reaction, i.e., reacylation catalyzed by acyltransferase, causes increased target cell lysis, presumably by increasing the products of PLA2 action. Platelet cytotoxicity is increased when platelets are pretreated with some products of PLA2: exogenous lysophospholipids and not free arachidonic acid increase cytotoxicity. Electron microscopy suggests that platelets and target cells may fuse, possibly as a result of the formation of lysophospholipids which are well-known membrane fusogens. Fixation with paraformaldehyde does not affect platelet cytotoxicity, suggesting that the complete cytotoxic system resides as a preformed complex in platelet membranes. The results indicate that platelet membrane-associated PLA2, together with receptors for Fc and complement, are required for platelet cytotoxicity.

Heat labile opsonins to pneumococcus. II. Involvement of C3 and C5.

When encapsulated type 25 pneumococci (Pn25) were opsonized with normal guinea pig serum, they consumed much more C3 than other complement (C) components. Fixation of C3 to the organisms was demonstrated by radio-labeling techniques, and its capsular localization was established by the use of monospecific anti-C3 antibody. Treatment of the serum with an appropriate dose of a purified cobra venom factor (VF) destroyed C3 and all of the opsonic activity, without appreciably affecting the other C components. Addition of purified C3 completely restored the opsonic activity of the VF-treated serum, indicating a requirement for C3. Since purified C3 alone had no opsonic activity, it was concluded that the C3 molecules had to be cleaved (to C3b) to function as opsonins. Experiments with C5-deficient mice revealed that C5 also plays a definite, but quantitatively less impressive, role in antipneumococcal defense.

Evidence for the involvement of the Ss protein of the mouse in the hemolytic complement system.

A significant within-strain correlation has been demonstrated between the levels of Ss and hemolytic complement (C) activity in two Ss-high strains. Mouse serum specifically depleted of Ss by absorption with F(ab')2 fragments of anti-Ss had negligible C activity. In control experiments, Ss-specific antigen-antibody complexes formed with F(ab')2 fragments did not fix rabbit C, and bovine serum albumin-specific antigen-antibody complexes formed with F(ab')2 fragments did not fix mouse C. Therefore the removal of C activity by anti-Ss [F(ab')2] was apparently not due to C fixation. These results suggest that the Ss protein is a necessary component of the C system.

Analysis of major histocompatibility complex haplotypes of t-chromosomes reveals that the majority of diversity is generated by recombination.

t-chromosomes are natural polymorphisms in feral populations of mice that are thought to be descended from a single ancestral chromosome. They carry an inversion of at least 10 cM surrounding the major histocompatibility complex (MHC) that effectively prevents recombination between a t-bearing chromosome and wild type chromosomes. However, on the rare occasion when two different t-chromosomes meet in a wild female, recombination occurs at an apparently normal rate. Since they contain the highly polymorphic MHC, their limited origin and restricted chances for recombination make t-chromosomes a valuable tool for studying the relative contributions of mutation and recombination to the generation of diversity. Using 13 different serological reagents to class I antigens, and studying restriction enzyme polymorphisms detected with three molecular probes for class II genes examined with three endonucleases, we present data indicating that the major factor responsible for the diversity of class I antigens is recombination, but that for class II genes, mutation must play an important role in addition to recombination.

Antibody-mediated suppression of grafted lymphoma cells. II. Participation of macrophages.

Specific alloantibody admixed with a grafted murine lymphoma is suppressive of the graft in mice of the inbred strain native to the tumor. Suppressive capacity of the host is obviated in mice given 500 R whole body irradiation before tumor inoculation but is restored when normal peritoneal macrophages are admixed with the tumor-antibody inoculum. Other normal cell types admixed with the tumor-antibody inoculum are not effective in restoring suppressive capacity.

Hyaluronan fragments activate an NF-kappa B/I-kappa B alpha autoregulatory loop in murine macrophages.

Macrophages play an important role in the acute tissue inflammatory response through the release of cytokines and growth factors in response to stimuli such as lipopolysaccharide (LPS). Macrophage inflammatory effector functions are also influenced by interactions with the extracellular matrix (ECM). Such macrophage-ECM interactions may be important in regulating chronic inflammatory responses. Recent evidence has suggested that hyaluronan (HA), a glycosaminoglycan (GAG) component of ECM can induce inflammatory gene expression in murine macrophages. HA exists in its native form as a large polymer, but is found as smaller fragments under inflammatory conditions. The NF-kappa B/I-kappa B transcriptional regulatory system has been shown to be a critical component of the host inflammatory response. We examined the effects of high molecular weight HA and lower molecular weight HA fragments on NF-kappa B activation in mouse macrophages. Only the smaller HA fragments were found to activate NF-kappa B DNA binding activity. After HA stimulation, I-kappa B alpha mRNA was induced and I-kappa B alpha protein levels, which initially decreased, were restored. The induction of I-kappa Balpha expression was not observed for other GAGs. The time course of I-kappa B alpha protein regeneration in response to HA fragments was consistent with an autoregulatory mechanism. In support of this mechanism, in vitro translated murine I-kappa B alpha inhibited HA fragment-induced NF-kappa B DNA binding activity. The NF-kappa B DNA binding complex in HA-stimulated extracts was found to contain p50 and p65 subunits. Activation of the NF-kappa B/I-kappa B system in macrophages by ECM fragments may be an important mechanism for propagating the tissue inflammatory response.

Resistance of neoplasms to immunological destruction: role of a macrophage chemotaxis inhibitor.

Several tissue culture lines of 6C3HED, a murine lymphoma, were more susceptible to immunologic destruction in vivo than the highly virulent 6C3HED line maintained by serial intramuscular transplantation. The attenuated tissue culture cells were rejected by normal syngeneic recipients, but thymectomized mice were unable to reject attenuated cells. In such mice, the growth rate of attenuated cells was equivalent to the growth rate of virulent cells in normal syngeneic mice. The increased susceptibility of attenuated cells to destruction by syngeneic hosts was shown to correlate with decreased production by the tumor cells of a macrophage chemotaxis inhibitor, and not with altered antigen density. In addition, when inhibitor isolated from virulent cells was administered to mice challenged with attenuated cells, the latter cells became virulent in vivo. When attenuated and virulent cells were administered simultaneously in the same host, the attenuated cells were able to develop into progressively growing tumors. The data suggest that the successful growth of neoplastic cells in normal may require tumor cells to produce factors which subvert the ability of the host to mobilize macrophages rapidly at the tumor site.