PPAR-gamma agonist protects podocytes from injury

Podocyte injury and loss contribute to progressive glomerulosclerosis. Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is a nuclear hormone receptor, which we have found to be increased in podocytes in a variety of kidney diseases. It is not known if PPAR-gamma contributes to renal injury or if it serves as a countermeasure to limit renal injury during disease progression. We tested these possibilities utilizing the puromycin aminonucleoside (PAN) model of renal injury in immortalized mouse podocytes. The cultured podocytes expressed PPAR-gamma mRNA at baseline but this was decreased by PAN. Pioglitazone, a pharmacologic agonist of PPAR-gamma, increased both PPAR-gamma mRNA and activity in injured podocytes, as assessed by a reporter plasmid assay. Further, pioglitazone significantly decreased PAN-induced podocyte apoptosis and necrosis while restoring podocyte differentiation. The PPAR-gamma agonist significantly restored expression of the cyclin-dependent kinase inhibitor p27 and the antiapoptotic molecule Bcl-xL while significantly decreasing proapoptotic caspase-3 activity. Pioglitazone tended to decrease PAN-induced transforming growth factor-beta (TGF-beta) mRNA expression. Our study shows that PPAR-gamma is normally expressed by podocytes and its activation is protective against PAN-induced apoptosis and necrosis. We postulate that this protective effect may be mediated in part by effects on p27 and TGF-beta expression.

Medication safety program reduces adverse drug events in a community hospital

BACKGROUND

There is widespread interest in improving medication safety, particularly in the hospital setting. Numerous suggestions have been made as to how this should be done, but there is a paucity of data demonstrating the effectiveness of any of the interventions that have been proposed.

OBJECTIVES

To assess the impact of a wide ranging, community hospital based patient safety program on patient harm as measured by the rate of adverse drug events.

DESIGN

An audit of discharged hospital patients was conducted from January 2001 to December 2003. Baseline data were collected for the first 6 months and multiple drug protocols and other interventions were instituted on the nursing units and in the pharmacy department over the subsequent 9 months (transition period). These interventions were largely based on information about medication risks acquired from internal medication event reporting. Each month of the study adverse drug events (ADE) were sought from a random sample of inpatient charts. A trigger tool was used to detect clues to ADEs, the presence of which was confirmed or excluded by detailed manual chart review. The severity of these events was categorized using the classification system of the National Coordinating Council for Medication Error and Reporting and Prevention.

MAIN OUTCOME MEASURES AND RESULTS

Median ADEs per 1000 doses of medication dispensed declined significantly from 2.04 to 0.65 (p<0.001). Median ADEs per 100 patient days declined significantly from 5.07 to 1.30 (p<0.001). The proportion of inpatients with one or more ADE in the baseline period was 31% and declined threefold (p<0.001). The severity of reported medication events also declined. The number of ADEs associated conclusively with patient harm was 1.67 per total doses delivered in the baseline period and declined eightfold (p<0.001).

CONCLUSION

The implementation of a carefully planned series of low cost interventions focused on high risk medications, driven by information largely from internal event reporting, and designed to improve a hospital's medication safety leads to a significant decrease in patient harm.

Complexities of the herbal nomenclature system in traditional Chinese medicine (TCM): lessons learned from the misuse of Aristolochia-related species and the importance of the pharmaceutical name during botanical drug product development

Herbs used in traditional Chinese medicine (TCM) have diverse cultural/historical backgrounds and are described based on complex nomenclature systems. Using the family Aristolochiaceae as an example, at least three categories of nomenclature could be identified: (1) one-to-one (one plant part from one species): the herb guan mutong refers to the root of Aristolochia manshuriensis; (2) multiple-to-one (multiple plant parts from the same species serve as different herbs): three herbs, madouling, qingmuxiang and tianxianteng, derived respectively from the fruit, root and stem of Aristolochia debilis; and (3) one-to-multiple (one herb refers to multiple species): the herb fangji refers to the root of either Aristolochia fangchi, Stephania tetrandra or Cocculus trilobus; in this case, the first belongs to a different family (Aristolochiaceae) than the latter two (Menispermaceae), and only the first contains aristolochic acid (AA), as demonstrated by independent analytical data provided in this article. Further, mutong (Akebia quinata) is allowed in TCM herbal medicine practice to be substituted with either guan mutong (Aristolochia manshuriensis) or chuan mutong (Clematis armandii); and mu fangji (Cocculus trilobus) by guang fanchi (Aristolochia fangchi) or hanzhong fangji (Aristolochia heterophylla), thereby increasing the risk of exposing renotoxic AA-containing Aristolochia species to patients. To avoid these and other confusions, we wish to emphasize the importance of a pharmaceutical name, which defines the species name, the plant part, and sometimes the special process performed on the herb, including cultivating conditions. The pharmaceutical name as referred to in this article is defined, and is limited to those botanicals that are intended to be used as drug. It is hoped that by following the pharmaceutical name, toxic herbs can be effectively identified and substitution or adulteration avoided.

Rolipram, a phosphodiesterase 4 inhibitor, prevented cancellous and cortical bone loss by inhibiting endosteal bone resorption and maintaining the elevated periosteal bone formation in adult ovariectomized rats

Cyclic AMP (cAMP) is a continually produced nucleotide inactivated by hydrolysis to 5'AMP via phosphodiesterase (PDE) enzymes. Rolipram is a selective PDE4 inhibitor reported to have anti-inflammatory effects and used in the treatment of asthma and chronic obstructive pulmonary disease (COPD). The current study was designed to determine whether Rolipram could prevent and restore bone loss in ovariectomized (OVX) rats. Six-month-old Sprague Dawley rats underwent either sham-operated or bilateral ovariectomy, and were left untreated for 60 days to develop osteopenia. Then they were treated with vehicle, 6 mg/kg PGE(2), 3 microg/kg Alendronate or 0.1-1.0 mg/kg Rolipram for 60 days. At sacrifice, the right tibiae were processed for quantitative bone histomorphometric measurements. The right femurs were measured by dual energy A-ray absorptiometry and the 5th lumbar vertebrae were subjected to micro-computed tomography to access bone mass and architecture changes. Our results indicated that OVX induced negative bone balance in all five bone sites we tested, with bone resorption exceeding bone formation. Rolipram at 0.1-0.6 mg/kg dose levels prevented while at 1 mg/kg restored ovariectomy-induced cancellous and cortical bone loss in the tibia, femur and lumbar vertebra. Dynamic bone histomorphometry suggested that these beneficial effects were achieved by partially maintaining the elevated bone formation at the trabecular bone surface and increasing bone formation at the periosteal bone surface of the cortex. Furthermore, it reduced bone turnover at the trabecular and the endocortical bone surfaces. The prevention of further bone loss effects were comparable to those of an anti-resorption agent (Alendronate) but were not as great as those of an anabolic agent (PGE(2)). In addition, Rolipram treatment increased body and muscle weights compared to the vehicle-treated OVX rats. In conclusion, our study in an osteopenic rat model suggested that a selective PDE4 inhibitor may be used for the treatment of established osteoporosis.

Non-viral siRNA delivery to the lung

SiRNAs exert their biological effect by guiding the degradation of their cognate mRNA sequence, thereby shutting down the corresponding protein production (gene silencing by RNA interference or RNAi). Due to this property, siRNAs are emerging as promising therapeutic agents for the treatment of inherited and acquired diseases, as well as research tools for the elucidation of gene function in both health and disease. Because of their lethality and prevalence, lung diseases have attracted particular attention as targets of siRNA-mediated cures. In addition, lung is accessible to therapeutic agents via multiple routes, e.g., through the nose and the mouth, thus obviating the need for targeting and making it an appealing target for RNAi-based therapeutic strategies. The clinical success of siRNA-mediated interventions critically depends upon the safety and efficacy of the delivery methods and agents. Delivery of siRNAs relevant to lung diseases has been attempted through multiple routes and using various carriers in animal models. This review focuses on the recent progress in non-viral delivery of siRNAs for the treatment of lung diseases, particularly infectious diseases. The rapid progress will put siRNA-based therapeutics on fast track to the clinic.

Identification of Novel Superior Polycationic Vectors for Gene Delivery by High-throughput Synthesis and Screening of a Combinatorial Library

PURPOSE

Low efficiency and toxicity are two major drawbacks of current non-viral gene delivery vectors. Since DNA delivery to mammalian cells is a multi-step process, generating and searching combinatorial libraries of vectors employing high-throughput synthesis and screening methods is an attractive strategy for the development of new improved vectors because it increases the chance of identifying the most overall optimized vectors.

MATERIALS AND METHODS

Based on the rationale that increasing the effective molecular weight of small PEIs, which are poor vectors compared to the higher molecular weight homologues but less toxic, raises their transfection efficiency due to better DNA binding, we synthesized a library of 144 biodegradable derivatives from two small PEIs and 24 bi- and oligo-acrylate esters. A 423-Da linear PEI and its 1:1 (w/w) mixture with a 1.8-kDa branched PEI were cross-linked with the acrylates at three molar ratios in DMSO. The resulting polymers were screened for their efficiency in delivering a beta-galactosidase expressing plasmid to COS-7 monkey kidney cells. Selected most potent polymers from the initial screen were tested for toxicity in A549 human lung cancer cells, and in vivo in a systemic gene delivery model in mice employing a firefly luciferase expressing plasmid.

RESULTS

Several polycations that exhibited high potency and low toxicity in vitro were identified from the library. The most potent derivative of the linear 423-Da PEI was that cross-linked with tricycle-[5.2.1.0]-decane-dimethanol diacrylate (diacrylate 14), which exhibited an over 3,600-fold enhancement in efficiency over the parent. The most potent mixed PEI was that cross-linked with ethylene glycol diacrylate (diacrylate 4) which was over 850-fold more efficient than the physically mixed parent PEIs. The relative efficiencies of these polymers were even up to over twice as high as that of the linear 22-kDa PEI, considered the "gold standard" for in vitro and systemic gene delivery. The potent cross-linked polycations identified were also less toxic than the 22-kDa PEI. The optimal vector in vivo was the mixed PEI cross-linked with propylene glycol glycerolate diacrylate (diacrylate 7); it mediated the highest gene expression in the lungs, followed by the spleen, with the expression in the former being 53-fold higher compared to the latter. In contrast, the parent PEIs mediated no gene expression at all under similar conditions, and injection of the polyplexes of the 22-kDa PEI at its optimal N/P of 10 prepared under identical conditions killed half of the mice injected.

CONCLUSIONS

High-throughput synthesis and transfection assay of a cross-linked library of biodegradable PEIs was proven effective in identifying highly transfecting vectors. The identified vectors exhibited dramatically superior efficiency compared to their parents both in vitro and in an in vivo systemic gene delivery model. The majority of these vectors mediated preferential gene delivery to the lung, and their in vivo toxicity paralleled that in vitro.

The type 1 equilibrative nucleoside transporter regulates anxiety-like behavior in mice

Activation of adenosine receptors in the brain reduces anxiety-like behavior in animals and humans. Because nucleoside transporters regulate adenosine levels, we used mice lacking the type 1 equilibrative nucleoside transporter (ENT1) to investigate whether ENT1 contributes to anxiety-like behavior. The ENT1 null mice spent more time in the center of an open field compared with wild-type littermates. In the elevated plus maze, ENT1 null mice entered more frequently into and spent more time exploring the open arms. The ENT1 null mice also spent more time exploring the light side of a light-dark box compared with wild-type mice. Microinjection of an ENT1-specific antagonist, nitrobenzylthioinosine (nitrobenzylmercaptopurine riboside), into the amygdala of C57BL/6J mice reduced anxiety-like behavior in the open field and elevated plus maze. These findings show that amygdala ENT1 modulates anxiety-like behavior. The ENT1 may be a drug target for the treatment of anxiety disorders.

Stage-dependent reactivity of thymocytes to self-peptide--MHC complexes

In mice that express a transgene for the 2C T cell antigen-receptor (TCR) and lack a recombinase-activating gene (2C(+)RAG(-/-) mice) most of the peripheral T cells are CD8(+), a few are CD4(+), and a significant fraction are CD4(-)CD8(-) [double negative (DN)]. The DN 2C cells, like DN T cells that are abundant in various other alphabeta TCR-transgenic mice, appear to be derived directly from DN thymocytes that prematurely express the TCR transgene. The DN 2C cells are virtually absent in mice deficient in major histocompatibility complex class II (MHC-II) but more abundant in mice deficient in MHC-I, suggesting that the DN 2C thymocytes are positively selected by self-peptide-MHC-II (pMHC-II) complexes and negatively selected by self-pMHC-I complexes. The pMHC-I complexes, however, positively select CD8(+) 2C T cells in the same mice. The different effects of thymic pMHC-I on DN and CD8(+) thymocytes are consistent with the finding that DN 2C thymocytes are more sensitive than more mature CD4(+)CD8(+) [double positive (DP)] thymocytes to a weak pMHC-I agonist for the 2C TCR. Together with previous evidence that DP thymocytes respond more sensitively than T cells in the periphery to weak pMHC agonists, the findings suggest progressive decreases in responsiveness to self-pMHC-I complexes as thymocytes develop from DN to DP thymocytes and then to mature naïve T cells in the periphery.

Loss of expression of Kruppel-like factor 6 in primary hepatocellular carcinoma and hepatoma cell lines

KLF6 (Zf9, COPEB), an ubiquitous transcription factor, maps to chromosome 10p. Recently, KLF6 was found to have a more generalized role in tumorigenesis as a candidate tumor suppressor gene for some tumors. However, results from other published studies seem not to be in agreement with data from previous studies. Gene-expression analysis is increasingly important in biological research. Loss of expression is one of the mechanisms to functionally inactivate a tumor suppressor gene. To investigate the expression change of KLF6 gene associated with HCC as a step toward a better understanding of the molecular pathophysiology, and to provide the basis for analysis of KLF6 gene in HCC carcinogenesis. We analyzed the expression of KLF6 mRNA in 26 samples of HCC tissues and hepatoma cell lines(Hep3B and HepG2) detected by Real-Time quantitative RT-PCR (qRT-PCR) and conventional RT-PCR assay. To confirm and extend the data obtained at RNA level, we performed detailed immunoblotting analysis on HCC tissues and hepatoma cell lines using a rabbit polyclonal antibody specific for KLF6. NKLF6 detected by qRT-PCR from HCC and corresponding noncancerous tissues was 0.04+/-0.038 and 0.116+/-0.101, respectively. These data demonstrated that KLF6 mRNA level was significantly decreased in HCC, compared with corresponding noncancerous tissues (t =3.683 , P<0.001). The frequency of Hepatoma Cell Lines with KLF6 down-regulation detected by conventional PT-PCR, seems to be consistent with a previous study using real-time PCR assays in tumor samples. KLF6 expression levels were determined by Western blot. Compared to the matched surrounding tissues, a clear decrease of KLF6 protein levels in tumor tissues was observable (t=13.59, P<0.001). Hepatoma cell lines also showed low-level of KLF6 protein (P<0.01) expression. Immunohistochemistry and immunocytochemistry showed a faint diffused staining in the HCC tissues and hepatoma cell lines, and endogenous KLF6 protein was detected mostly in the cytoplasm. KLF6 gene appeared markedly reduced in HCC tissues and hepatoma cell lines. Frequent down-regulation of KLF6 strongly suggested that it is a candidate of tumor suppressor gene for HCC.

Mechanical shear wave induced by piezoelectric ceramics for magnetic resonance elastography

Magnetic resonance elastography (MRE) is a noninvasive technique to measure elasticity of tissues in vivo. For MRE, an additional actuator is needed to be mounted on an observed object, and to excite the object. In this paper, an experiment is set to obtain MR mechanical shear wave images. A novel actuator is proposed to generate mechanical wave propagating inside a gel phantom. The actuator is made of piezoelectric ceramics, and is fixed on a plexiglass bracket. Both of the gel phantom and the actuator are put into a head coil in the scanner's bore. The actuator works synchronously with an imaging sequence running on the scanner. The sequence is modified from a FLASH sequence, into a motion-sensitizing phase-contrast sequence, for shear wave imaging. Wave images are presented to show the effect of those factors, such as the stiffness of the phantoms, the frequency of the actuator, the parameters of the motion-sensitizing gradient, and the oscillation of the patient bed.

Observation of Upsilon(3S)-->tau+tau- and tests of lepton universality in Upsilon decays

Using data collected with the CLEO III detector at the CESR e+e- collider, we report on a first observation of the decay Upsilon(3S)-->tau+tau-, and precisely measure the ratio of branching fractions of Upsilon(nS), n=1, 2, 3, to tau+tau- and mu+mu- final states, finding agreement with expectations from lepton universality. We derive absolute branching fractions for these decays, and also set a limit on the influence of a low mass CP-odd Higgs boson in the decay of the Upsilon(1S).

Determination of suitable pretreatment method for old-intermediate landfill leachate

For old-intermediate landfill leachate, the high concentrations of ammonium and low BOD/COD (B/C) ratios are the main obstacles to biological treatment. Magnesium ammonium phosphate (MAP) precipitation (struvite precipitation) and Fenton oxidation were employed as pretreatment options on this type of leachate. Results revealed that at optimum operating conditions of pH 9 and MAP ratio of 1:1:1, ammonium and COD were reduced by 97.8% from 2132 mg l(-1) to 46 mg l(-1) and by 50.0% from 4113 mg l(-1) to 2057 mg l(-1), respectively using struvite precipitation. COD was lowered by 76% and ammonium by 6.3% using Fenton oxidation at optimized conditions of H2O2 dosage of 3500 mg l(-1), Fe2+ dosage of 437.5 mg l(-1), pH 4, a mass ratio of 8 for H2O2: Fe2+ dosage and reaction time of 30 minutes. At their respective operating conditions, the B/C ratios for both pre-treatment methods were increased from 0.35 in the raw leachate to 0.66 and 0.71, for MAP precipitation and Fenton oxidation respectively, values that are suitable for biological treatment. This study shows that struvite precipitation is a suitable pretreatment option resulting in the simultaneous removal of ammonium and organic matter in old-intermediate landfill leachate.

Proteomic analysis of steroid-triggered autophagic programmed cell death during Drosophila development

Two morphological forms of programmed cell death, apoptosis and autophagic cell death, remove unneeded or damaged cells during animal development. Although the mechanisms that regulate apoptosis are well studied, little is known about autophagic cell death. A shotgun proteome analysis of purified dying larval salivary glands in Drosophila was used to identify proteins that are expressed during autophagic programmed cell death. A total of 5661 proteins were identified from stages before and after the onset of cell death. Analyses of these data enabled us to identify proteins from a number of interesting categories including regulators of transcription, the apoptosis, autophagy, lysosomal, and ubiquitin proteasome degradation pathways, and proteins involved in growth control. Several of the identified proteins, including the serine/threonine kinase warts (Wts), were not detected using whole-genome DNA microarrays, providing support for the importance of such high-throughput proteomic technology. Wts regulates cell-cycle arrest and apoptosis, and significantly, mutations in wts prevent destruction of salivary glands.

Prediction of linear B-cell epitopes using amino acid pair antigenicity scale

Identification of antigenic sites on proteins is of vital importance for developing synthetic peptide vaccines, immunodiagnostic tests and antibody production. Currently, most of the prediction algorithms rely on amino acid propensity scales using a sliding window approach. These methods are oversimplified and yield poor predicted results in practice. In this paper, a novel scale, called the amino acid pair (AAP) antigenicity scale, is proposed that is based on the finding that B-cell epitopes favor particular AAPs. It is demonstrated that, using SVM (support vector machine) classifier, the AAP antigenicity scale approach has much better performance than the existing scales based on the single amino acid propensity. The AAP antigenicity scale can reflect some special sequence-coupled feature in the B-cell epitopes, which is the essence why the new approach is superior to the existing ones. It is anticipated that with the continuous increase of the known epitope data, the power of the AAP antigenicity scale approach will be further enhanced.

NOTCH1-induced T-cell leukemia in transgenic zebrafish

Activating mutations in the NOTCH1 gene have been found in about 60% of patients with T-cell acute lymphoblastic leukemia (T-ALL). In order to study the molecular mechanisms by which altered Notch signaling induces leukemia, a zebrafish model of human NOTCH1-induced T-cell leukemia was generated. Seven of sixteen mosaic fish developed a T-cell lymphoproliferative disease at about 5 months. These neoplastic cells extensively invaded tissues throughout the fish and caused an aggressive and lethal leukemia when transplanted into irradiated recipient fish. However, stable transgenic fish exhibited a longer latency for leukemia onset. When the stable transgenic line was crossed with another line overexpressing the zebrafish bcl2 gene, the leukemia onset was dramatically accelerated, indicating synergy between the Notch pathway and the bcl2-mediated antiapoptotic pathway. Reverse transcription-polymerase chain reaction analysis showed that Notch target genes such as her6 and her9 were highly expressed in NOTCH1-induced leukemias. The ability of this model to detect a strong interaction between NOTCH1 and bcl2 suggests that genetic modifier screens have a high likelihood of revealing other genes that can cooperate with NOTCH1 to induce T-ALL.

Bcl-2 family proteins are essential for platelet survival

Platelets are relatively short-lived, anucleated cells that are essential for proper hemostasis. The regulation of platelet survival in the circulation remains poorly understood. The process of platelet activation and senescence in vivo is associated with processes similar to those observed during apoptosis in nucleated cells, including loss of mitochondrial membrane potential, caspase activation, phosphatidylserine (PS) externalization, and cell shrinkage. ABT-737, a potent antagonist of Bcl-2, Bcl-X(L), and Bcl-w, induces apoptosis in nucleated cells dependent on these proteins for survival. In vivo, ABT-737 induces a reduction of circulating platelets that is maintained during drug therapy, followed by recovery to normal levels within several days after treatment cessation. Whole body scintography utilizing ([111])Indium-labeled platelets in dogs shows that ABT-737-induced platelet clearance is primarily mediated by the liver. In vitro, ABT-737 treatment leads to activation of key apoptotic processes including cytochrome c release, caspase-3 activation, and PS externalization in isolated platelets. Despite these changes, ABT-737 is ineffective in promoting platelet activation as measured by granule release markers and platelet aggregation. Taken together, these data suggest that ABT-737 induces an apoptosis-like response in platelets that is distinct from platelet activation and results in enhanced clearance in vivo by the reticuloendothelial system.