N1-(Benzenesulfonyl)tryptamines as novel 5-HT6 antagonists

N-Benzenesulfonyl-5-methoxy-N,N-dimethyltryptamine (BS/5-OMe DMT; 5) was shown to bind at human 5-HT6 serotonin receptors with high affinity (Ki = 2.3 nM) relative to serotonin (Ki = 78 nM). Structural variation failed to result in significantly enhanced affinity. BS/5-OMe DMT acts as an antagonist of 5-HT-stimulated adenylate cyclase (pA2 = 8.88 nM) and may represent the first member of a novel class of 5-HT6 antagonists.

Real-time biomass-concentration monitoring in animal-cell cultures

The accurate, on-line measurement of cell concentration in animal-cell cultures is an on-going problem in bioprocess engineering, and the development of new monitoring techniques is an area of intensive and fruitful research. This article summarizes the recent advances, trends and problems in this field and focuses, in particular, on optical sensors, including the latest laser and infrared probes. Alternative methods, such as multiple-extinction fluorimetry, real-time imaging and particle-size analysis, are also discussed. Although many of these techniques are still at an experimental stage, we believe that some of them have been developed sufficiently that we advocate their routine use in bioprocess monitoring and control.

Stable and monodisperse lipoplex formulations for gene delivery

A stable single vial lipoplex formulation has been developed that can be stored frozen without losing either biological activity or physical stability. This formulation was identified by systematically controlling several formulation variables and without introducing either stabilizers or surfactants. Analytical assays were used to unambiguously characterize the formulations. The critical formulation parameters were: (1) the size of the cationic liposomes; (2) the rate and method of DNA and cationic liposome mixing; and (3) the ionic strength of the suspending vehicle. The mixing conditions were precisely controlled by using a novel, specially designed continuous flow pumping system in which the DNA and liposome solutions were mixed at the junction of a T-connector. Homogenous cationic liposome preparations were prepared by extrusion in two different size ranges of either 400 or 100 nm. Extruded liposomes produced more monodisperse and physically stable lipoplex formulations than unextruded liposomes, but the formulations prepared with 100 nm liposomes were less active in in vitro transfection assays than either the 400 nm or unextruded liposomes. Low ionic strength and 5% sorbitol were required for the lipoplex formulations to survive freezing and thawing. A frozen lipoplex formulation stored for more than a year maintained its biological activity. These results have broad implications for the pharmaceutical development of lipoplex formulations for gene delivery.

Converting an alcohol to an amine in a cationic lipid dramatically alters the co-lipid requirement, cellular transfection activity and the ultrastructure of DNA-cytofectin complexes

Cytofectins are positively charged lipophilic molecules that readily form complexes with DNA and other anionic polynucleotides. Normally, cytofectins are combined with an activity-augmenting phospholipid such as dioleoylphosphatidylethanolamine (DOPE), and a film of dried, mixed lipid is prepared and hydrated to form cationic liposomes. The liposome solution is then mixed with a plasmid DNA solution to afford cytofectin-DNA complexes which, when presented to living cells, are internalized and the transgene is expressed. One of the most potent cytofectins, dimyristoyl Rosenthal inhibitor ether (DMRIE), is presently being used to deliver transcriptionally active DNA into human tumor tissues. Here we report the remarkable consequences of replacing the alcohol moiety of DMRIE with a primary amine. The resulting cytofectin, called beta-aminoethyl-DMRIE (betaAE-DMRIE), promoted high level transfection over a broad range of DNA and cationic lipid concentrations. A comparison of in vitro transfection activity between DMRIE and betaAE-DMRIE in 10 cell types revealed that betaAE-DMRIE was more active than DMRIE, and that betaAE-DMRIE, unlike DMRIE, was maximally effective in the absence of colipid. The consequences of the alcohol-to-amine conversion on the structure of the cytofectin/DNA complex was also examined by Atomic Force Microscopy. Strikingly dissimilar images were found for plasmid DNA alone and for the plasmid complexes of betaAE-DMRIE and DMRIE/DOPE.

HLA-E gene polymorphism associated with susceptibility to Kawasaki disease and formation of coronary artery aneurysms

OBJECTIVE

Kawasaki disease (KD) is a pediatric systemic vasculitis of unknown cause for which a genetic influence is supposed. The purpose of this study was to identify possible genetic variants in the major histocompatibility complex (MHC) region that are associated with KD and the development of coronary artery aneurysms (CAAs) in a Taiwanese population.

METHODS

The 168 genetic variants covering the MHC locus were analyzed in an association study of a Taiwanese cohort of 93 KD patients and 680 unrelated healthy children matched for sex and age with the study patients.

RESULTS

Eleven single-nucleotide polymorphisms (SNPs) were associated with the occurrence of KD. The SNP located at the 3'-untranslated region of HLA-E (rs2844724) was highly associated (P < 1 x 10(-7)). In addition, the frequency of the C allele was higher in KD patients without CAAs than in controls (P < 0.001) due to a significantly increased frequency of the CC and CT genotypes. Plasma levels of soluble HLA-E were significantly higher in KD patients than in controls regardless of the presence of CAAs. Furthermore, there was a trend toward higher plasma levels of soluble HLA-E in KD patients with the CT and TT genotypes of the HLA-E gene polymorphism.

CONCLUSION

Our results suggest that the HLA-E gene polymorphism may play a role in the pathogenesis of KD.

Analytical methods for the characterization of cationic lipid-nucleic acid complexes

Five analytical assays are described that provide a platform for systematically evaluating the effect of formulation variables on the physical properties of cationic lipid-DNA complexes (lipoplexes). The assays are for (i) lipid recovery, (ii) total DNA, (iii) free DNA, (iv) nuclease sensitivity, and (v) physical stability by filtration. Lipid recovery was determined by measuring lipid primary amino groups labeled with the fluorescamine reagent in the presence of the detergent Zwittergent. Zwittergent was effective at disrupting lipoplexes, making the primary amine accessible to the fluorescamine reagent. Total DNA was determined with the PicoGreen reagent, also in the presence of Zwittergent. The PicoGreen assay in the absence of Zwittergent gave the percentage of the total DNA that was not complexed with cationic lipid. The results of this assay for free DNA agreed well with the amount of DNA that could be separated from complexes by centrifugation as well as with the amount of DNA that was accessible to DNase I digestion. Monitoring the lipid and DNA recoveries after filtration through polycarbonate membranes provided a quantitative method for assessing changes in lipoplex physical characteristics. Together, these assays provide a convenient high-throughput approach to assess physical properties of lipoplexes, allowing systematic evaluation of different formulations.

Control of long-term perfusion Chinese hamster ovary cell culture by glucose auxostat

The strategies for control of the feed rate in high-density perfusion cultures of animal cells are limited to several simple schemes. While in an industrial environment simplicity is seen as a major advantage, the need for more elaborate closed-loop control methods that can improve process stability in long-term continuous cultures is also well understood. What has prevented the application of the advanced control strategies known from theory is the lack of reliable real-time information that can be used to close the feedback loop. Among the variables that are appropriate for direct feedback control of the perfusion rate, high priority should be given to the glucose concentration. Unlike some other environmental variables, such as dissolved oxygen and pH, it provides unambiguous information which facilitates the selection of the right feed rate. The present paper describes the application of a closed loop control scheme, known as a "glucose-stat", to the long-term cultivation of Chinese hamster ovary cells in a high-density (35-40 million cells/mL) perfusion process. The monitoring and control system worked successfully for more than 2.5 months without any signs of performance degradation. In targeting industrial application, issues such as reliability, sterility, and accuracy, are given high priority. The implementation of the glucose monitoring system, which is the main part of the control complex, is addressed in details. The performance of the perfusion culture was evaluated at four different glucose set points, providing essential information about process optimization. It became evident that the perfusion culture was operated in the so-called "high-gain" zone (where the system is highly sensitive to the dilution rate), which justifies the application of a feedback control. The on-line glucose concentration was also used by an embedded expert system which drove the process through the batch and the perfusion phase, achieving total computer control of the feed rate. In summary, the proposed glucose monitoring and control technique proved to be a reliable biotechnology tool which can be applied with confidence at an industrial scale to either microbial or mammalian cell cultures.

Intracavitary liposome-mediated p53 gene transfer into glioblastoma with endogenous wild-type p53 in vivo results in tumor suppression and long-term survival

A cavitary glioblastoma model was created by injection of RT-2 cells, which express endogenous wild type p53, into the peritoneal cavity of nude mice. This model developed multiple layers of tumor cells invading the peritoneal surface and was used to mimic the postoperative surgical cavity remaining after glioblastoma (GBM) excision in patients. Rhodamine labeled DMRIE/DOPE + DNA complexes were found to penetrate at least 20 tumor cell layers. Injection of p53 gene/liposome complexes into the intraperitoneal cavity after the tumor was established resulted in massive tumor necrosis. Prominent staining of human p53 protein using the DO-1 antibody was found in tumor cells near the necrotic lesions. Tumor explants expressed human p53 protein and showed a 54% growth reduction in an in vitro growth assay. Further, DMRIE/DOPE mediated p53 gene transfection significantly increased the mean survival time of tumor bearing mice compared to vector control. These results demonstrate the efficiency of using exogenous wild type p53 to suppress glioblastoma cell with endogenous wild type p53 in vivo through liposome mediated transfection method.

Self-assembly in the carboxysome: a viral capsid-like protein shell in bacterial cells

Many proteins self-assemble to form large supramolecular complexes. Numerous examples of these structures have been characterized, ranging from spherical viruses to tubular protein assemblies. Some new kinds of supramolecular structures are just coming to light, while it is likely there are others that have not yet been discovered. The carboxysome is a subcellular structure that has been known for more than 40 years, but whose structural and functional details are just now emerging. This giant polyhedral body is constructed as a closed shell assembled from several thousand protein subunits. Within this protein shell, the carboxysome encapsulates the CO(2)-fixing enzymes, Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase) and carbonic anhydrase; this arrangement enhances the efficiency of cellular CO(2) fixation. The carboxysome is present in many photosynthetic and chemoautotrophic bacteria, and so plays an important role in the global carbon cycle. It also serves as the prototypical member of what appears to be a large class of primitive protein-based organelles in bacteria. A series of crystal structures is beginning to reveal the secrets of how the carboxysome is assembled and how it enhances the efficiency of CO(2) fixation. Some of the assembly principles revealed in the carboxysome are reminiscent of those seen in icosahedral viral capsids. In addition, the shell appears to be perforated by pores for metabolite transport into and out of the carboxysome, suggesting comparisons to the pores through oligomeric transmembrane proteins, which serve to transport small molecules across the membrane bilayers of cells and eukaryotic organelles.

Genetic studies on murine susceptibility to herpes simplex keratitis

We studied the influence of lgh-linked genes on the development of keratopathy after corneal inoculation with herpes simplex virus (HSV). Using congenic strains of mice, we found that the lgh-1 gene locus, or genes closely linked to it, influence the clinical expression of HSV infection. Mice with the lgh-1e or lgh-1d allotype routinely developed severe keratopathy after HSV corneal inoculation, whereas congenic strains with lgh-1a or lgh-1b allotype were less susceptible. Cell-mediated immune responses to HSV also differed between susceptible and resistant murine strains. We interpret our results to imply a genetic influence on cell-mediated, acquired immune responses to HSV infection.

Airway inflammation in smokers and nonsmokers with varying responsiveness to ozone

Exposure to ozone causes symptoms, changes in lung function, and airway inflammation. We studied whether individuals who differ in lung-function responsiveness to ozone, or in smoking status, also differ in susceptibility to airway inflammation. Healthy subjects were selected on the basis of responsiveness to a classifying exposure to 0.22 ppm ozone for 4 h with exercise (responders, with a decrease in FEV1 > 15%; and non-responders, with a decrease in FEV1 < 5%). Three groups were studied: nonsmoker-nonresponders (n = 12), nonsmoker-responders (n = 13), and smokers (n = 13, 11 nonresponders and two responders). Each subject underwent two exposures to ozone and one to air, separated by at least 3 wk; bronchoalveolar and nasal lavages were performed on three occasions: immediately (early) and 18 h (late) after ozone exposure, and either early or late after air exposure. Recovery of polymorphonuclear leukocytes (PMN) increased progressively in all groups, and by up to 6-fold late after ozone exposure. Interleukin-6 (IL-6) and IL-8 increased early (by up to 10-fold and up to 2-fold, respectively), and correlated with the late increase in PMN. Lymphocytes, mast cells, and eosinophils also increased late after exposure. We conclude that ozone-induced airway inflammation is independent of smoking status or airway responsiveness to ozone.

Ibuprofen overdose complicated by renal failure, adult respiratory distress syndrome, and metabolic acidosis

Acute ingestion of ibuprofen commonly results in no symptoms, or minor gastrointestinal or central nervous system manifestations. While most cases of ibuprofen overdose do well, serious toxicity may occur, and is difficult to predict. A case of ibuprofen overdose is presented in which the course was complicated by metabolic acidosis, adult respiratory distress syndrome, and renal failure necessitating prolonged dialysis.

Disease association of the interleukin-18 promoter polymorphisms in Taiwan Chinese systemic lupus erythematosus patients

Interleukin (IL)-18, an important mediator of innate and adaptive immunity, plays multiple roles in chronic inflammation, in autoimmune diseases, in a variety of cancers and in number of infectious diseases. IL-18 promoter polymorphisms have been also noted associated with various inflammatory diseases. We investigated the association of IL-18 promoter polymorphisms (-656T/G, -607A/C and -137C/G) with systemic lupus erythematosus (SLE) in Taiwan Chinese patients and controls. Six haplotypes (hts) were identified from the three promoter polymorphisms. The genotype distribution of the ht1 (GCC), ht2 (TAC), ht4 (GAC) and ht5 (TCC) were different in patients and controls (P<0.002). Moreover, the haplotype and genotype frequencies of ht1 were significantly increased in patients with discoid rash (P=0.045, odds ratio (OR): 2.01, 95% confidence interval (CI): 1.01-4.00; P=0.027, OR: 5.13, 95% CI: 1.41-18.68). In addition, the homozygous genotype ht1/ht1 was significant increased in patients with serositis (P=0.015, OR: 9.78, 95% CI: 1.55-61.73). These observations suggest that the three promoter polymorphisms contribute to the genetic background of SLE pathogenesis.

The application of intramolecular radical cyclizations of acylsilanes in the regiospecific formation of cyclic silyl enol ethers

Acylsilanes with terminal alpha-stannyl bromide or xanthate functionalities are prepared. Alpha-stannyl radicals generated from these acylsilanes undergo intramolecular cyclizations to give cyclic silyl enol ethers regiospecifically. The radical processes involve radical cyclization, Brook rearrangement, and beta-fragmentation in sequence. A tributylstannyl group serves as the radical leaving group. The newly formed sigma-bond and pi-bond are located between the same two carbon atoms. This approach is limited to the formation of five-membered rings. In another route, omega-bromo-alpha-phenylsulfonylacylsilanes are synthesized. The radical cyclizations of these alpha-sulfonylacylsilanes also give cyclic silyl enol ethers. The phenylsulfonyl moiety is the radical leaving group in this system. Furthermore, the newly formed sigma-bond and pi-bond are located at adjacent positions sharing a single carbon atom. The latter approach is effective for both five- and six-membered ring formation.

An examination of O-2-isocephems as orally absorbable antibiotics

The synthesis and structure-activity relationships of a series of orally absorbed O-2-isocephems are described. These compounds possessed a D-[(p-hydroxyphenyl)glycyl]amino substituent at the 7-position while the substituent at the 3-position was varied. Relative to the analogous cephems, the O-2-isocephems exhibited comparable to better activity against Gram-positive organisms. Against Gram-negative organisms, their activity was variable but did indicate a lower beta-lactamase stability. Following oral administration, the O-2-isocephems generally exhibited longer half-lives but lower Cmax's and urinary recoveries.

The burden of influenza-like illness in the US workforce

BACKGROUND

The disease burden of influenza-like illnesses (ILIs) on the working population has been documented in the literature, but statistical evidence of ILI-related work absenteeism in the USA is limited due to data availability.

AIMS

To assess work absenteeism due to ILIs among privately insured employees in the USA in 2007-8 and 2008-9.

METHODS

We used the 2007-9 MarketScan® research databases. Full-time employees aged 18-64 years, with the ability to incur work absence and continuously enrolled in the same insurance plan during each season were included. We identified ILI episodes using ICD-9 codes for influenza and pneumonia (480-487). For each season, we calculated the mean work-loss hours per ILI episode and the proportion of employees who had at least one ILI episode. Work-loss hours and ILI rates were examined by subgroups.

RESULTS

The mean number of work hours lost per ILI episode was 23.6 in 2007-8 and 23.9 in 2008-9. The proportion of employees with at least one ILI was 1.7% in 2007-8 and 1.2% in 2008-9. In both seasons, the proportion with ILI was higher among older (2.1 and 1.5%) and hourly workers (2.0 and 1.3%), workers in the southern region (1.9 and 1.3%) and those in oil, gas or mining industries (1.9 and 1.4%).

CONCLUSIONS

Our results indicate that the disease burden associated with ILIs in the working population is not trivial and deserves attention from policymakers and health care professionals to design effective strategies to reduce this burden.

Ozone exposure and the production of reactive oxygen species by bronchoalveolar cells in humans

Exposure to ozone injures respiratory epithelium, and the mechanisms may involve the generation of reactive oxygen species (ROS). This study tested the hypothesis that ozone exposure increases the airway burden of ROS to a greater degree in smokers than nonsmokers, and that this effect is independent of ozone-induced changes in spirometry. Healthy subjects were selected as either responders (decrement in FEV1 > 15%) or nonresponders (decrement in FEV1 < 5%) to ozone; each underwent 2 exposures to ozone and 1 to air, with bronchoalveolar lavage (BAL) performed 30 min (early) and 18 h (late) after exposure. Release of superoxide anion (O2(-)) was used as a measure of ROS release by all BAL cells, and flow cytometry was used to detect ROS production in alveolar macrophages (AM) only. Recovery of AM was approximately threefold greater in smokers than nonsmokers. Unstimulated, but not stimulated, cells obtained by BAL from smokers released approximately twofold greater amounts of O2(-) than cells from nonsmokers, both early and late after ozone exposure (p =.012 and p =.046, respectively). Stimulated, but not unstimulated, ROS generation by AM from smokers increased following ozone exposure, but the ozone effect was not significant. ROS production by AM decreased in nonsmokers (air vs. ozone late, p =.014). Total protein, albumin, and immunoglobulin M (IgM) increased in BAL fluid, consistent with an increase in epithelial permeability. In addition, the concentration of alpha2-macroglobulin increased approximately threefold 18 h after exposure in nonsmokers (p <.001). No relationship was found between measures of ROS production and lung function responsiveness to ozone. These studies suggest the airways of smokers experience a greater burden of ROS than those of nonsmokers following ozone exposure.

Two-dimensional characterization of prostatic acid phosphatase, prostatic specific antigen and prostate binding protein in expressed prostatic fluid

Specimens of pooled prostatic fluid, collected by rectal massage from men under 50 years of age with no apparent prostatic disorders, were subjected to two-dimensional gel electrophoresis to study the composition of its proteins. In a preliminary study, a total of 57 major protein groups were detected. In the present study, we attempted to identify, in the two-dimensional gels, those that are related to prostate-associated proteins, i.e., prostatic acid phosphatase (PAP), prostatic specific antigen (PSA), and prostate binding protein (PBP). Individual proteins were recognized by the procedure of Western Blot using specific antisera with peroxidase-antiperoxidase as the staining reagent. Each protein spot in the two-dimensional gel was expressed, along the abscissa, by its isoelectric point (pI) and, along the ordinate, by the molecular weight (MW). PAP consisted of a train of more than ten protein spots that occupied an area in the gel from pI 7.0, MW 45,000 to pI 6.0, MW 50,000. Four protein spots with a MW of 34,000 and a pI range of 8.2-8.8 were identified as PSA. PBP was observed as having three protein spots that were located at pI 5.6-6.6 with a single MW of 15,000. For PAP and PSA, additional protein spots with lower MWs also stained positively with the specific antisera, suggestive of the presence of degradative products of these proteins. Following the removal of the serum-related proteins by an extensive absorption with anti-human serum antibody by affinity chromatography, the prostatic fluid contained 27 major groups of non-serum proteins. These non-serum proteins in the prostatic fluid included PAP, PSA, PBP, and their related smaller molecular species. These results indicate that the prostatic fluid contains PAP, PSA, PBP and that their presence and the patterns of their distribution in the two-dimensional gels should be considered as the characteristic property of the prostatic secretions.

Penetration of cefprozil into middle ear fluid of patients with otitis media

Penetration of cefprozil into the middle ear fluid was investigated in patients with chronic otitis media. A total of 89 patients ranging from 7 months to 11 years old participated in the study. The middle ear fluid was removed by ventilation tubes inserted through the tympanic membrane at times ranging from 0.38 to 5.97 h after oral administration of a single dose of 15 or 20 mg/kg of body weight. A blood sample was also collected as soon as the middle ear fluid was removed. Plasma samples were analyzed for the concentration of cefprozil by a high-performance liquid chromatographic assay. Middle ear fluid samples were analyzed for the concentration of cefprozil by a microbiological assay. The concentrations of cefprozil in plasma ranged from 0.38 to 15.97 micrograms/ml at the 15-mg/kg dose level and from 1.28 to 21.47 micrograms/ml at the 20-mg/kg dose level. The corresponding middle ear fluid concentrations of cefprozil ranged from 0.06 to 4.44 micrograms/ml and from 0.17 to 8.67 micrograms/ml, respectively. Cefprozil penetrates well into middle ear fluid in patients with chronic otitis media.

Effects of olfactory bulbectomy on NMDA receptor density in the rat brain:

Olfactory bulbectomy (OBX) transects the glutamatergic efferents from the olfactory bulbs, and the changes of glutamatergic N-methyl-D-aspartate (NMDA) receptor-mediated function are though to be involved in the behavioral deficits seen in OBX rats. In the present study, irritability scores in OBX male Wistar rats were correlated with discrete regional effects on NMDA receptor function measured using a [3H] MK-801 binding assay. Irritability scores, measured before and for 2 weeks after OBX, showed a gradual increase in irritability after OBX. A reduction of the NMDA receptor density was observed in the cerebral cortex and amygdala 16 days after OBX, but not in the striatum, olfactory tubercle, entorhinal cortex, and hippocampus. These results demonstrate that OBX causes changes in the NMDA receptor system in certain brain regions and suggest that these changes may be responsible for the behavioral deficits of OBX rats.