Safety and pharmacokinetics of nelfinavir during the second and third trimesters of pregnancy and postpartum

PURPOSE

Evaluate the safety, tolerability, and pharmacokinetics (PK) of nelfinavir during pregnancy and postpartum in HIV-infected women.

METHODS

Phase IV, non-randomized, open-label study of nelfinavir 625 mg tablets (1250 mg) in combination with lamivudine/zidovudine twice daily. Primary endpoint was treatment-related or possibly treatment-related gastrointestinal or hepatic adverse events (AEs). Selected maternal and infant outcomes were recorded. Frequent plasma samples were collected for PK studies during the 2nd and 3rd trimesters, and 6 weeks postpartum, to analyze total and free nelfinavir and M8 concentrations.

RESULTS

Sixteen HIV+ pregnant women were enrolled. Six mild treatment-related AEs and 3 serious AEs occurred; 1 serious AE (elevated AST) met the primary endpoint. Compared with 6 weeks postpartum, levels of total nelfinavir were reduced by 44% and 46%, total M8 by 82% and 83%, free nelfinavir by 48% and 39%, and free M8 by 83% and 79% in the 2nd and 3rd trimesters, respectively. At 6 weeks postpartum, 75% and 50% of subjects maintained HIV-1 RNA levels <400 and <50 copies/mL, respectively. All pregnancies resulted in live births without transmission in 15 infants.

CONCLUSIONS

Nelfinavir in combination with lamivudine/zidovudine was generally well tolerated. Total and free nelfinavir and M8 exposure were reduced in late pregnancy.

STM imaging of electronic waves on the surface of Bi2Te3: topologically protected surface states and hexagonal warping effects

Scanning tunneling spectroscopy studies on high-quality Bi2Te3 crystals exhibit perfect correspondence to angle-resolved photoemission spectroscopy data, hence enabling identification of different regimes measured in the local density of states (LDOS). Oscillations of LDOS near a step are analyzed. Within the main part of the surface band oscillations are strongly damped, supporting the hypothesis of topological protection. At higher energies, as the surface band becomes concave, oscillations appear, dispersing with a wave vector that may result from a hexagonal warping term.

Immunoglobulin M red blood cell alloantibodies are frequently adsorbed by rabbit erythrocyte stroma

BACKGROUND

Rabbit erythrocyte stroma (RESt, Immucor) adsorption is often used to remove cold autoantibodies from patient samples to facilitate detection of underlying alloantibodies. However, reports in the literature show that adsorption of clinically significant alloantibodies can occur. A 2006 study by Storry and colleagues suggested that immunoglobulin (Ig)M antibodies are adsorbed by RESt regardless of antigen specificity. In our study, we further investigated the adsorption of IgM red blood cell alloantibodies by RESt.

STUDY DESIGN AND METHODS

A total of 12 sera containing monoclonal IgM antibodies of various specificities (anti- D, -C, -c, -E, -e, -K, -Jk(b), and -S) and titers, which were all shown to exhibit only IgM reactivity after dithiothreitol treatment, and two sera with polyclonal IgG (anti-Fy(a) and -K) were all adsorbed by RESt. Titers of unadsorbed, once-adsorbed, and twice-adsorbed IgM and IgG antibodies were determined in parallel.

RESULTS

Ten of the 12 monoclonal IgM samples showed significant (more than fourfold) reduction in titer after RESt adsorptions. Both of the polyclonal IgG samples tested showed insignificant (fourfold or less) reduction in titer.

CONCLUSIONS

RESt is known to effectively remove IgM cold autoantibodies. Our results show that monoclonal IgM alloantibodies are also frequently adsorbed by RESt with significant reduction in titer. Adsorption is variable and some IgM alloantibodies are not adsorbed. Further studies may elucidate the effect of RESt adsorption on IgG alloantibodies. Caution is needed when RESt is employed to remove interferences by cold autoantibodies in pretransfusion testing, and the risk of missed IgM alloantibodies must be considered.

Pharmacokinetics of azithromycin in serum, bronchial washings, alveolar macrophages and lung tissue following a single oral dose of extended or immediate release formulations of azithromycin

OBJECTIVES

Antibacterial efficacy of azithromycin could be improved by achieving higher concentrations at the sites of infection. Azithromycin extended release (azithromycin-ER) formulation was developed to enable a higher dosage of 2 g to be administered as a single oral dose without decreasing the safety profile. The aim of this study was to compare the pharmacokinetics of azithromycin in serum, epithelial lining fluid (ELF), alveolar macrophages (AMs) and lung tissue following a single oral dose of azithromycin-ER or azithromycin immediate release (azithromycin-IR) formulation.

PATIENTS AND METHODS

A total of 64 patients, diagnosed with lung cancer, requiring open-chest surgery for lung resection, completed the study. Subjects were randomized to receive oral administration of either a single 2 g dose of azithromycin-ER (32 subjects) or a single 500 mg dose of azithromycin-IR (32 subjects). Simultaneously, subjects within each treatment group were randomized to one of eight specific nominal post-dose time points for bronchoalveolar lavage and lung tissue sampling. Results For azithromycin-IR formulation, the AUC(0-24) in serum, ELF, AMs and lung tissue was 3.1, 2.3, 1674 mg.h/L and 130 mg.h/kg, respectively. For azithromycin-ER formulation, the AUC(0-24) in serum, ELF, AMs and lung tissue were 10.0, 17.6, 7028 mg.h/L and 505 mg.h/kg, respectively. The AUC(0-24) ratio following administration of azithromycin-ER relative to azithromycin-IR was 3.2, 7.7, 4.2 and 3.9 in serum, ELF, AMs and lung tissue, respectively.

CONCLUSIONS

Within the first 24 h, a single 2 g azithromycin-ER dose produced dose-related increase in systemic exposure compared with a single 500 mg azithromycin-IR dose, which resulted in higher levels of azithromycin in ELF, AMs and lung tissue. Both formulations had similar safety profiles. By achieving high azithromycin exposure early in the course of treatment, without compromising tolerability, azithromycin-ER shows the potential for improved antibacterial efficacy compared with azithromycin-IR.

Tetanus toxin production in soy-based medium: nutritional studies and scale-up into small fermentors

AIMS

To further improve the soy-based medium, devoid of animal and dairy products, for a production of tetanus toxin by nutritional studies and to scale-up the Clostridium tetani process into small fermentors.

METHODS AND RESULTS

Optimum production of tetanus toxin did not require addition of pantothenic acid, thiamine, riboflavin, pyridoxine, biotin and uracil, growth factors used by previous investigators. Furthermore, l-tyrosine and l-cysteine could be eliminated from our soy-based medium without effect. Seven carbon sources were compared with glucose in the soy-based medium, but none was found to be superior to glucose. The process was successfully scaled-up into 250-ml bottles, 1-l bottles and 1-l fermentors.

CONCLUSIONS

Quite remarkably, when comparing the tetanus production process in our soy-based medium with the traditional animal/dairy-containing media, our medium does not require addition of expensive vitamins, uracil or carbon sources other than glucose. Furthermore, the l-tyrosine and l-cysteine components could be eliminated, making the medium (Hy-Soy, glucose, powdered iron and inorganic salts) much more simple and economical. The successful scale-up from test tubes into 1-l fermentors allows us to predict that further scale-up into large fermentors will be successful.

SIGNIFICANCE AND IMPACT OF THE STUDY

Toxoid preparations made from toxin produced with animal and dairy products can contain undesirable contaminants such as the prion causing bovine spongiform encephalopathy (BSE; mad cow's disease) or antigenic peptides that stimulate anaphylactic reactions and other undesirable immune reactions in immunized hosts. Our vegetable-based process avoids such unfortunate possibilities. The medium, having been made simpler and less expensive, and shown to be scaleable from test tubes into small fermentors, should be excellent for large scale production of tetanus toxin.

STM studies of TbTe3: evidence for a fully incommensurate charge density wave

We observe unidirectional charge density wave (CDW) ordering on the quasi-2D material TbTe3 with a scanning tunneling microscope at approximately 6 K. Our analysis indicates that the CDW is fully incommensurate, with wave vector qCDW approximately 0.71x2pi/c. By imaging at various tip-sample voltages, we highlight effects of the subsurface layer and its effect on the CDW. We also observe an additional (possibly surface) dimerization and approximately 0.68x2pi/a ordering perpendicular to the CDW.

Metabolites from the fungusCephalosporium sp. AL031

A new pyrone derivative, 7, 9-dihydroxy-10-methyl-2H, 4aH, 6H, 10bH-pyrano[5,6-c][2]ben-zopyran-2,6-dione (1), was isolated from a culture broth of a strain of the fungus Cephalosporium sp. AL031, together with three known compounds, 3-acetyl-7-hydroxy-5-methoxyl-3H-isobenzofuran-1-one (2), vermopyrone (3), and 5-methylmellein (4). Their structures were elucidated by spectroscopic analysis including MS and 2D-NMR. Compounds 2, 3, and 4 are reported for the first time from fermentation broth of this fungus through the present study.

Compounds with DNA cleaving activity from Kadsura ananosma

Two DNA cleavage agents, meso-dihydroguaiaretic acid (1) and isobavachalcone (2) together with the known alpha-ylangene, beta-sitosterol, daucosterol, pentacosane, hexacosanic acid and cerotic acid 1-monoglyceride were isolated from the stem barks of Kadsura ananosma Kerr for the first time. Compounds 1 and 2 showed relaxation of supercoiled DNA to nicked DNA. 1 represented a new structural type of DNA cleavage agent, while 2 was reported to show DNA strand-scission activity for the first time. 1 also showed significant cytotoxic effect on Hela and Leukemia cells in vitro.

Menstrum for culture preservation and medium for seed preparation in a tetanus toxin production process containing no animal or dairy products

AIMS

To completely eliminate animal and dairy products from the lyophilization menstrum and the seed medium used to produce tetanus toxin with Clostridium tetani.

METHODS AND RESULTS

Tetanus toxin production in a recently developed fermentation medium lacking animal and dairy products was studied with different seed media. It was found that soy peptone could completely replace the beef heart infusion plus animal peptone previously used as seed medium. In addition, we found that cells lyophilized in soy milk could replace the usual type of cells lyophilized in cow's milk.

CONCLUSIONS

We have now developed a complete tetanus toxin production process containing no animal and dairy products.

SIGNIFICANCE AND IMPACT OF THE STUDY

Toxoid preparations made from toxin produced with animal and dairy products can contain undesirable contaminants such as the prion causing bovine spongiform encephalopathy (Mad Cow's Disease) or antigenic peptides that stimulate anaphylactic reactions and other undesirable immune reactions in immunized hosts. The new vegetable-based process described here avoids such unfortunate possibilities.

Secondary metabolism in simulated microgravity

We have studied microbial secondary metabolism in a simulated microgravity (SMG) environment provided by NASA rotating-wall bioreactors (RWBs). These reactors were designed to simulate some aspects of actual microgravity that occur in space. Growth and product formation were observed in SMG in all cases studied, i.e., Bacillus brevis produced gramicidin S (GS), Streptomyces clavuligerus made beta-lactam antibiotics, Streptomyces hygroscopicus produced rapamycin, and Escherichia coli produced microcin B17 (MccB17). Of these processes, only GS production was unaffected by SMG; production of the other three products was inhibited. This was determined by comparison with performance in an RWB positioned in a different mode to provide a normal gravity (NG) environment. Carbon source repression by glycerol of the GS process, as observed in shaken flasks, was not observed in the RWBs, whether operated in the SMG or NG mode. The same phenomenon occurred in the case of MccB17 production, with respect to glucose repression. Thus, the negative effects of carbon source on GS and beta-lactam formation are presumably dependent on shear, turbulence, and/or vessel geometry, but not on gravity. Stimulatory effects of phosphate and the precursor L-lysine on beta-lactam antibiotic production, as observed in flasks, also occurred in SMG. An almost complete shift in the localization of produced MccB17 from cells to extracellular medium was observed when E. coli was grown in the RWB under SMG or NG. If a plastic bead was placed in the RWB, accumulation became cellular, as it is in shaken flasks, indicating that sheer stress favors a cellular location. In the case of rapamycin, the same type of shift was observed, but it was less dramatic, i.e., growth in the RWB under SMG shifted the distribution of produced rapamycin from 2/3 cellular:1/3 extracellular to 1/3 cellular:2/3 extracellular. Stress has been shown to induce or promote secondary metabolism in a number of other microbial systems. RWBs provide a low stress SMG environment, which, however, supports only poor production of MccB17, as compared to production in shaken flasks. We wondered whether the poor production in RWBs under SMG is due to the low level of stress, and whether increasing stress in the RWBs would raise the amount of MccB17 formed. We found that increasing shear stress by adding a single Teflon bead to the RWB improved MccB17 production. Although shear stress seems to have a marked positive effect on MccB17 production in SMG, addition of various concentrations of ethanol to RWBs (or to shaken flasks) failed to increase MccB17 production. Ethanol stress merely decreased production and, at higher concentrations, inhibited growth. Interestingly, cells growing in the RWB were much more resistant to the growth- and production-inhibitory effects of ethanol than cells growing in shaken flasks. With respect to S. hygroscopicus, addition of Teflon beads to the RWB reversed the inhibition of growth, but rapamycin production was still markedly inhibited, and the distribution did not revert back to a preferential cellular site.

Flexible carbon nanotube membrane sensory system: a generic platform

Multi-walled carbon nanotube membrane as obtained from soft lithography-mediated selective chemical-vapor deposition template approach has been successfully integrated with flexible elastomeric polydimethylsiloxane framework to fabricate microsensing devices. Two proof-of-concept experiments, namely high-sensitivity chemical gas sensing and electrochemical detection have been performed to demonstrate its potential as a useful generic platform for general purposes sensory system.

[Microtrebeculectomy in glaucoma]

OBJECT

To study the clinical effectiveness of microtrabeculectomy.

METHODS

Of 80 patients (80 eyes) with various types of glaucoma, 40 (40 eyes) underwent microtrabeculectomy. The scleral flap measures 2 mm x 2 mm. The rectangular resection of trabeculum measures 1 mm x 1 mm. And 40(40 eyes) underwent standard trabeculectomy with the scleral flap measuring 3 mm x 4 mm and the resection of trebeculum measuring 1.0 mm x 3.0 mm. Vision acuity, intraocular pressure (IOP) measurements, slit lamp examinations and opthalmicroscope examinations were performed before surgery and after surgery at one, two, eight and 15 days, and one, two, three, six, nine, 12, and 18 months.

RESULTS

The mean preoperative IOP was 44.11 +/- 14.86 mmHg(1 mmHg = 0.133 kPa) for microtrabeculectomy and 46.45 +/- 11.27 mmHg for standard trabeculectomy. The mean postoperative IOP and operative complications were similar between the two groups. The mean postoperative IOP was 12.94 +/- 4.13 mmHg for the group with microtrabeculectomy and 13.51 +/- 3.56 mmHg for the group with standard trabeculectomy at the end of follow-up (12-18 months). The incidence of shallow anterior chamber was 16% (6/40) in micro group, while it was 2.6% (1/40) in the other group. There was no significant difference between the two groups(X2 = 1.59 < 3.84, P > 0.05).

CONCLUSION

Microtrabeculectomy appears to provide reasonable control of IOP.

Shear stress enhances microcin B17 production in a rotating wall bioreactor, but ethanol stress does not

Stress, including that caused by ethanol, has been shown to induce or promote secondary metabolism in a number of microbial systems. Rotating-wall bioreactors provide a low stress and simulated microgravity environment which, however, supports only poor production of microcin B17 by Escherichia coli ZK650, as compared to production in agitated flasks. We wondered whether the poor production is due to the low level of stress and whether increasing stress in the bioreactors would raise the amount of microcin B17 formed. We found that applying shear stress by addition of a single Teflon bead to a rotating wall bioreactor improved microcin B17 production. By contrast, addition of various concentrations of ethanol to such bioreactors (or to shaken flasks) failed to increase microcin B17 production. Ethanol stress merely decreased production and, at higher concentrations, inhibited growth. Interestingly, cells growing in the bioreactor were much more resistant to the growth-inhibitory and production-inhibitory effects of ethanol than cells growing in shaken flasks.

Induction of microcin B17 formation in Escherichia coli ZK650 by limitation of oxygen and glucose is independent of glucose consumption rate

We examined the consumption of glucose from the media in which Escherichia coli ZK650 was grown. This organism, which produces the polypeptide antibiotic microcin B17 best under conditions of limiting supplies of glucose and air, was grown with a low level of glucose (0.5 mg/ml) as well as a high level (5.0 mg/ml) under both high and low aeration. Glucose consumption rates were virtually identical under both high and low aeration. Thus, glucose consumption rate is not a regulating factor in microcin B17 formation.

The natural functions of secondary metabolites

Secondary metabolites, including antibiotics, are produced in nature and serve survival functions for the organisms producing them. The antibiotics are a heterogeneous group, the functions of some being related to and others being unrelated to their antimicrobial activities. Secondary metabolites serve: (i) as competitive weapons used against other bacteria, fungi, amoebae, plants, insects, and large animals; (ii) as metal transporting agents; (iii) as agents of symbiosis between microbes and plants, nematodes, insects, and higher animals; (iv) as sexual hormones; and (v) as differentiation effectors. Although antibiotics are not obligatory for sporulation, some secondary metabolites (including antibiotics) stimulate spore formation and inhibit or stimulate germination. Formation of secondary metabolites and spores are regulated by similar factors. This similarity could insure secondary metabolite production during sporulation. Thus the secondary metabolite can: (i) slow down germination of spores until a less competitive environment and more favorable conditions for growth exist; (ii) protect the dormant or initiated spore from consumption by amoebae; or (iii) cleanse the immediate environment of competing microorganisms during germination.

Methionine interference in rapamycin production involves repression of demethylrapamycin methyltransferase and S-adenosylmethionine synthetase

In a chemically defined medium, L-methionine decreased production of rapamycin and increased that of demethylrapamycin. Growth with L-methionine yielded cells with a lower ability to convert demethylrapamycin to rapamycin and decreased the level of S-adenosylmethionine synthetase and S-adenosylmethionine. Thus, methionine represses at least one methyltransferase of rapamycin biosynthesis and S-adenosylmethionine synthetase.

Growth of Steptomyces hygroscopicus in rotating-wall bioreactor under simulated microgravity inhibits rapamycin production

Growth of Streptomyces hygroscopicus under conditions of simulated microgravity in a rotating-wall bioreactor resulted in a pellet form of growth, lowered dry cell weight, and inhibition of rapamycin production. With the addition of Teflon beads to the bioreactor, growth became much less pelleted, dry cell weight increased but rapamycin production was still markedly inhibited. Growth under simulated microgravity favored extracellular production of rapamycin, in contrast to a greater percentage of cell-bound rapamycin observed under normal gravity conditions.

Relief from glucose interference in microcin B17 biosynthesis by growth in a rotating-wall bioreactor

Glucose interference in production of microcin B17 by Escherichia coli ZK650 was decreased sevenfold by growth in a ground-based rotating-wall bioreactor operated in the simulated microgravity mode as compared with growth in flasks. When cells were grown in the bioreactor in the normal gravity mode, relief from glucose interference was even more dramatic, amounting to a decrease in glucose interference of over 100-fold.