The Glucocorticoid-induced leucine zipper (GILZ) Is essential for spermatogonial survival and spermatogenesis

Spermatogenesis relies on the precise regulation of the self-renewal and differentiation of spermatogonia to provide a continuous supply of differentiating germ cells. The understanding of the cellular pathways regulating this equilibrium remains unfortunately incomplete. This investigation aimed to elucidate the testicular and ovarian functions of the glucocorticoid-induced leucine zipper protein (GILZ) encoded by the X-linked Tsc22d3 (Gilz) gene. We found that GILZ is specifically expressed in the cytoplasm of proliferating spermatogonia and preleptotene spermatocytes. While Gilz mutant female mice were fully fertile, constitutive or male germ cell-specific ablation of Gilz led to sterility due to a complete absence of post-meiotic germ cells and mature spermatozoa. Alterations were observed as early as postnatal day 5 during the first spermatogenic wave and included extensive apoptosis at the spermatogonial level and meiotic arrest in the mid-late zygotene stage. Overall, these data emphasize the essential role played by GILZ in mediating spermatogonial survival and spermatogenesis.

Control of Mycobacterium tuberculosis growth by activated natural killer cells

We characterized the underlying mechanisms by which glutathione (GSH)-enhanced natural killer (NK) cells inhibit the growth of Mycobacterium tuberculosis (M. tb) inside human monocytes. We observed that in healthy individuals, treatment of NK cells with N-acetyl cysteine (NAC), a GSH prodrug in conjunction with cytokines such as interleukin (IL)-2 + IL-12, resulted in enhanced expression of NK cytotoxic ligands (FasL and CD40L) with concomitant stasis in the intracellular growth of M. tb. Neutralization of FasL and CD40L in IL-2 + IL-12 + NAC-treated NK cells resulted in abrogation in the growth inhibition of M. tb inside monocytes. Importantly, we observed that the levels of GSH are decreased significantly in NK cells derived from individuals with HIV infection compared to healthy subjects, and this decrease correlated with a several-fold increase in the growth of M. tb inside monocytes. This study describes a novel innate defence mechanism adopted by NK cells to control M. tb infection.

Meclizine metabolism and pharmacokinetics: formulation on its absorption

Meclizine, an antihistamine, has been widely used for prophylactic treatment and management of motion sickness. However, the onset of action of meclizine was about 1 hour for the treatment of motion sickness and vertigo. A new suspension formulation of meclizine (MOS) was developed with the intention to achieve a rapid effect. To investigate the pharmacokinetics of the new MOS formulation versus the marketed meclizine oral tablet (MOT), a phase 1 pharmacokinetic study was performed in 20 healthy volunteers. In addition, an in vitro metabolic study using human hepatic microsome and recombinant CYP enzyme was also performed to determine the metabolic pathway in the human body. The plasma concentration of MOS appeared more rapidly in comparison to the MOT. The geometric mean ratios (90% confidence interval) of AUC(0-24) and AUC(0-∞) indicated no significant difference in bioavailability between the 2 formulations. CYP2D6 was found to be the dominant enzyme for metabolism of meclizine, and its genetic polymorphism could contribute to the large interindividual variability. In view of the similar bioavailability with a much shorter peak time of the plasma meclizine concentration from the MOS formulation, this new formulation is expected to produce a much quicker onset of action when used for the management of motion sickness.

Akt2/PKBbeta-sensitive regulation of renal phosphate transport

AIM

The protein kinase B (PKB)/Akt is known to stimulate the cellular uptake of glucose and amino acids. The kinase is expressed in proximal renal tubules. The present study explored the influence of Akt/PKB on renal tubular phosphate transport.

METHODS

The renal phosphate transporter NaPi-IIa was expressed in Xenopus oocytes with or without PKB/Akt and Na(+) phosphate cotransport determined using dual electrode voltage clamp. Renal phosphate excretion was determined in Akt2/PKBbeta knockout mice (akt2(-/-)) and corresponding wild-type mice (akt2(+/+)). Transporter protein abundance was determined using Western blotting and phosphate transport by (32)P uptake into brush border membrane vesicles.

RESULTS

The phosphate-induced current in NaPi-IIa-expressing Xenopus oocytes was significantly increased by the coexpression of Akt/PKB. Phosphate excretion [micromol per 24 h per g BW] was higher by 91% in akt2(-/-) than in akt2(+/+) mice. The phosphaturia of akt2(-/-) mice occurred despite normal transport activity and expression of the renal phosphate transporters NaPi-IIa, NaPi-IIc and Pit2 in the brush border membrane, a significantly decreased plasma PTH concentration (by 46%) and a significantly enhanced plasma 1,25-dihydroxyvitamin D(3) concentration (by 46%). Moreover, fractional renal Ca(2+) excretion was significantly enhanced (by 53%) and bone density significantly reduced (by 11%) in akt2(-/-) mice.

CONCLUSIONS

Akt2/PKBbeta plays a role in the acute regulation of renal phosphate transport and thus contributes to the maintenance of phosphate balance and adequate mineralization of bone.

Gibberellins: a phytohormonal basis for heterosis in maize

Four commercially important maize parental inbreds and their 12 F(1) hybrids were studied to investigate the role of the phytohormone gibberellin (GA) in the regulation of heterosis (hybrid vigor). All hybrids grew faster than any inbred. In contrast, all inbreds showed a greater promotion of shoot growth after the exogenous application of GA(3). Concentrations of endogenous GA(1), the biological effector for shoot growth in maize, and GA(19), a precursor of GA(1), were measured in apical meristematic shoot cylinders for three of the inbreds and their hybrids by gas chromatography-mass spectrometry with selected ion monitoring; deuterated GAs were used as quantitative internal standards. In 34 of 36 comparisons, hybrids contained higher concentrations of endogenous GAs than their parental inbreds. Preferential growth acceleration of the inbreds by exogenous GA(3) indicates that a deficiency of endogenous GA limits the growth of the inbreds and is thus a cause of inbreeding depression. Conversely, the increased endogenous concentration of GA in the hybrids could provide a phytohormonal basis for heterosis for shoot growth.

AZD1152 rapidly and negatively affects the growth and survival of human acute myeloid leukemia cells in vitro and in vivo

Aurora kinases play a critical role in regulating mitosis and cell division, and their overexpression has been implicated in the survival and proliferation of human cancer. In this study, we report the in vitro and in vivo activities of AZD1152, a compound that has selectivity for aurora B kinase, in acute myeloid leukemia (AML) cell lines, primary AML samples, and cord blood cells. AZD1152 exerted antiproliferative or cytotoxic effects in all cell lines studied, inhibited the phosphorylation of histone H3 (pHis H3) on Ser10 in a dose-dependent manner, and resulted in cells with >4N DNA content. THP-1 cells treated with AZD1152 accumulated in a state of polyploidy and showed a senescent response to the drug, in contrast to the apoptotic response seen in other cell lines. Accordingly, AZD1152 profoundly affected the growth of AML cell lines and primary AML in an in vivo xenotransplantation model. However, concentration-dependent effects on cell growth, apoptosis, and cell cycle progression were also observed when human cord blood and primary lineage-negative stem and progenitor cells were analyzed in vitro and in vivo. These data suggest that the inhibition of aurora B kinase may be a useful therapeutic strategy in the treatment of AML and that further exploration of dosing and treatment schedules is warranted in clinical trials.

Effects of a treatment adherence enhancement program on health literacy, patient-provider relationships, and adherence to HAART among low-income HIV-positive Spanish-speaking Latinos

The impact of an adherence enhancement program for low income HIV-infected Spanish-speaking Latinos on health literacy, patient-provider relationships, and adherence to HAART was examined. Evaluations were conducted at baseline, 6 weeks, and 6 months for participants (n = 85) randomly assigned to either the intervention group or a comparison group; 69 (81%) remained in the study for the entire 6-month duration. The intervention group scored significantly better than the comparison group on 3 of 5 measures of HIV health literacy at 6 weeks and on 2 of 5 measures, at 6 months. While there was a weak trend for the intervention group to report an increase in self-efficacy of medication adherence management, baseline to 6 weeks, no other changes were significant. Perceptions of the quality of relationship and communications with their HIV-treating physicians improved both at 6 weeks (p = 0.04) and at 6 months (p < 0.001). The comparison group showed little change baseline to 6 weeks and baseline to 6 months. While there was a trend for the pilot group to report better medication adherence, these differences were not statistically significant. Further evaluation of the impact of this adherence enhancement program is needed.

Steroid receptor coactivator-1 splice variants differentially affect corticosteroid receptor signaling

The mechanisms of receptor- and cell-specific effects of the adrenal corticosteroid hormones via mineralo- (MRs) and glucocorticoid receptors (GRs) are still poorly understood. Because the expression levels of two splice variants of the steroid receptor coactivator-1 (SRC-1) 1a and 1e, can differ significantly in certain cell populations, we tested the hypothesis that their relative abundance could determine cell- and receptor-specific effects of corticosteroid receptor-mediated transcription. In transient transfections, we demonstrate three novel types of SRC-1a- and SRC-1e-specific effects for corticosteroid receptors. One is promoter dependence: SRC-1e much more potently coactivated transcription from several multiple response element-containing promoters. Mammalian 1-hydrid studies indicated that this likely does not involve promoter-specific coactivator recruitment. Endogenous phenylethanolamine-N-methyltransferase mRNA induction via GRs was also differentially affected by the splice variants. Another type is receptor specificity: responses mediated by the N-terminal part of the MR, but not the GR, were augmented by SRC-1e at synergizing response elements. SRC fragment SRC(988-1240) by the MR but not the GR N-terminal fragment in a 1-hybrid assay. The last type, for GRs, is ligand dependence. Due to effects on partial agonism of RU486-activated GRs, different ratios of SRC-1a and 1e can lead to large differences in the extent of antagonism of RU486 on GR-mediated transcription. Furthermore, we show that SRC-1e but not SRC-1a mRNA expression was regulated in the pituitary by corticosterone. We conclude that the cellular differences in SRC-1a to SRC-1e ratio demonstrated in vivo might be involved in cell-specific responses to corticosteroids in a promoter- and ligand-dependent way.

Efficacy and safety of emtricitabine vs stavudine in combination therapy in antiretroviral-naive patients: a randomized trial

CONTEXT

Emtricitabine is a new, once-daily nucleoside reverse transcriptase inhibitor (NRTI) with potent activity against human immunodeficiency virus (HIV).

OBJECTIVE

To assess the efficacy and safety of emtricitabine as compared with stavudine when used with a background regimen of didanosine and efavirenz.

DESIGN, SETTING, AND PATIENTS

Randomized, double-blind, double-dummy study conducted at 101 research clinics in North America, Latin America, and Europe. The first patient was enrolled on August 21, 2000; no investigator or patient was unblinded until the last patient randomized completed the week 48 visit on October 24, 2002. Analyses were based on data collected in a double-blind setting with a median follow-up of 60 weeks. Patients were 571 antiretroviral-naive, HIV-1-infected adults aged 18 years or older with viral load levels greater than or equal to 5000 copies/mL.

INTERVENTIONS

Receipt of either 200 mg of emtricitabine once daily (plus stavudine placebo twice daily) (n = 286) or stavudine at standard doses twice daily (plus emtricitabine placebo once daily) (n = 285) plus open-label didanosine and efavirenz, once daily.

MAIN OUTCOME MEASURE

Persistent virological response, defined as achieving and maintaining viral load at or below the limit of assay quantification (< or =400 or 50 copies/mL).

RESULTS

At the interim analysis on June 14, 2002, when the last patient randomized completed 24 weeks of double-blind treatment (median follow-up time of 42 weeks), patients in the emtricitabine group had a higher probability of a persistent virological response < or =50 copies/mL vs the stavudine group (85% vs 76%, P =.005). This was associated with a higher mean CD4 cell count change from baseline for the emtricitabine group (156 cells/ microL vs 119 cells/microL, P =.01 [of note, there was no statistical difference at 48 weeks [P =.15], although a sensitivity analysis, using an intent-to-treat population with the last CD4 cell count observation carried forward to week 48 showed a difference [P =.02]]). The independent data and safety monitoring board recommended offering open-label emtricitabine based on the interim analysis. The probability of persistent virological response < or =50 copies/mL through week 60 was 76% for the emtricitabine group vs 54% for the stavudine group (P<.001). The probability of virological failure through week 60 was 4% in the emtricitabine group and 12% in the stavudine group (P<.001). Patients in the stavudine group had a greater probability of an adverse event that led to study drug discontinuation through week 60 than did those in the emtricitabine group (15% vs 7%, P =.005).

CONCLUSION

Once-daily emtricitabine appeared to demonstrate greater virological efficacy, durability of response, and tolerability compared with twice-daily stavudine when used with once-daily didanosine and efavirenz.

Multiparametric analysis of immature cell populations in umbilical cord blood and bone marrow

Adult stem cells are finding increased therapeutic potential not least in tissue regeneration protocols. The cell sources being proposed for such protocols include embryonic, umbilical cord blood (CB) and adult bone marrow (BM). Although embryonic sources are controversial, CB and marrow are available immediately. The appropriate cells of use in these sources are considered to be extremely rare and a characterisation of the starting cell source is important for the development of adult stem cell protocols and ex vivo expansion. Umbilical CB and BM mononuclear cells were labelled for the antigens CD34, CD133, CD117, CD164, Thy-1 or CD38, and additional intracellular CD34 antigen. Three dimensional flow-cytometric analyses were carried out together with dual laser confocal microscope analysis for antigen profile expression. Variable levels of immaturity were detected on CB and BM populations using internal and external CD34 antigen. For CB and BM cells, internal CD34 (intCD34+) could be detected on co-expressing CD133+ cells before expression of external CD34 antigen (extCD34+). CD38 co-expression analysis also showed that a small but distinct group of cells expressing low CD38 and no external CD34 antigen could be detected. Additional phenotyping of these cells using CD117, Thy-1, CD164 and CD133 demonstrated variable primitive status detectable within the external CD34- population. Newly harvested primary CB and BM populations were shown to contain not only cellular populations of known standard sequential maturity but also populations of more extreme rarity. The presence of cells which lacked extracellular CD34 antigen, in both CB and BM, but which possessed CD133, has important implications for purification of human stem cells in clinical applications.

Three-dimensional analysis of CD34 sialomucin distribution on cord blood and bone marrow

Determining the cellular distribution of key adhesion molecules may aid in understanding haematopoietic progenitor/stem cell (HPSC) homing to bone marrow (BM). CD34, a well-characterized marker for blast-like HPSC, is widely used for the isolation and enumeration of HPSC. Functional studies have yet to identify a ligand for CD34. However, growing evidence suggests that CD34 may aid the regulation of HPSC differentiation and modulate the expression of other HPSC adhesion molecules necessary for homing. This study aimed to determine CD34 distribution on umbilical cord blood (CB) and BM. CD34-selected cells were adhered to positively charged gold slides at room temperature, before indirect fluorescent antibody labelling with fluorescein isothiocyanate. Fluorescent distribution was determined by 1-microm interval, confocal laser scanning microscope Z-sections. Initial analysis showed CD34 distributed within peripheral halos and dense pocket regions. The development of three-dimensional imaging software enabled spatial visualization of CD34 distribution on CB and BM in association with differential interference contrast cell image. This showed that CD34 was distributed within peripheral halos, with magnupodia-associated 'meridian-shaped crescents', extending from points of cell-slide adhesion towards the top of the cell. True CD34 distribution, not previously discernible by confocal laser scanning microscopy alone, suggests a possible role in cell adhesion/homing revealed by three-dimensional imaging.

The serine/threonine kinases SGK2 and SGK3 are potent stimulators of the epithelial Na+ channel alpha,beta,gamma-ENaC

The serum- and glucocorticoid-inducible kinase 1 (SGK1) has been identified as a signalling molecule up-regulated by aldosterone, which stimulates the renal epithelial Na(+) channel ENaC. It is therefore thought to participate in the antinatriuretic action of this hormone. More recently, two isoforms, SGK2 and SGK3, have been cloned. The present study was performed to establish whether SGK2 and SGK3 influence ENaC activity similarly to SGK1. Dual-electrode voltage-clamp experiments in Xenopus laevis oocytes expressing alpha,ss,gamma-ENaC with or without SGK1, SGK2 or SGK3 revealed a stimulatory effect of all three kinases on the amiloride-sensitive current (I(Na)). To establish whether the SGK isoforms exert their effects through direct phosphorylation, we replaced the serine at the SGK consensus site of alphaENaC (alpha(S622A)ENaC) by site-directed mutagenesis. alpha(S622A),beta,gamma-ENaC was up-regulated similar to wild-type ENaC, suggesting that SGK isoforms do not act via direct phosphorylation of the transport proteins. In conclusion, SGK2 and SGK3 mimic the function of SGK1 and are likely to participate in the regulation of ENaC activity.

Efficacy and Safety of Twice-Daily versus Three-Times Daily Saquinavir Soft Gelatin Capsules as Part of Triple Combination Therapy for HIV-1 Infection

Objective

The objective of this study was to determine whether a triple therapy regimen incorporating twice-daily saquinavir is as effective as a three-times daily regimen.

Methods

This was an open-label, Phase III, multicentre, 48-week study involving 837 HIV-1-infected patients randomised to one of the following: saquinavir soft gel capsule (SGC) 1200 mg three-times daily, plus two nucleoside reverse transcriptase inhibitors (NRTIs) (arm A); saquinavir SGC 1600 mg twice-daily, plus two NRTIs (arm B); saquinavir SGC 1200 mg twice-daily and nelfinavir 1250 mg twice-daily, plus a single NRTI (arm C). The primary outcome measure was the virological response in arm A versus B and in arm A versus C with respect to the percentage of patients whose plasma HIV-1 RNA levels fell below the level of quantification for the Amplicor assay (<400 copies/ml) at weeks 24 and 48.

Results

At 48 weeks, the percentage of patients with plasma HIV-1 RNA levels <400 copies/ml was 47.1% (arm A), 45.3% (arm B) and 42.7% (arm C) in the intention-to-treat analysis. The treatment difference between arm B–arm A was -1.8% (95% confidence intervals -10.1, 6.5) and for arm C–arm A was -4.5% (95% confidence intervals -12.7, 3.7) in the intention-to-treat analysis. These differences fell within the maximum allowable difference (±12%) for arm B compared with arm A. At week 24, the percentage of patients with HIV-1 RNA levels <400 copies/ml was 59.6% (arm A), 57.6% (arm B) and 51.3% (arm C).

Conclusions

A twice-daily triple therapy regimen incorporating saquinavir SGC plus two NRTIs was of equivalent efficacy to the three-times daily regimen studied. All regimens were generally well tolerated.

The sizes and characteristics of the minority ethnic populations of Great Britain--latest estimates

This article presents estimates of the minority ethnic populations of Great Britain in 2000 and describes the regional distributions of the different groups. It also discusses changes in the sizes of the different minority ethnic populations during the 1990s. The paper provides information on some key demographic features of these populations at the end of the 1990s--age and sex structures, proportions born in the United Kingdom and whether children lived with their natural parents.

The demographic situation in the European Union

This article draws selected material from the annual Yearbook on Demography (2000 edition) published by Eurostat, the Statistical Office of the European Communities. Some key comparisons with other regions of the world are included, together with a broad picture of the demographic situation in the European Union. Topic coverage is selective.

The role of SGK1 in hormone-regulated sodium transport

Ion transport in epithelia is regulated by a variety of hormonal and nonhormonal factors, including mineralocorticoids, insulin, shear stress and osmotic pressure. In mammals, the mineralocorticoid aldosterone is the principal regulator of sodium homeostasis and hence is central to the control of extracellular fluid volume and blood pressure. Aldosterone acts through a member of the nuclear receptor superfamily, the mineralocorticoid receptor (MR), to control the transcriptional activity of specific target genes. Recently, a serine/threonine kinase, SGK1 (serum and glucocorticoid-regulated kinase isoform 1) was identified as a candidate mediator of aldosterone action in the colon and distal nephron. The aldosterone-activated MR increases SGK1 gene transcription and SGK1, in turn, strongly stimulates the activity of the epithelial sodium channel (ENaC). Interestingly, other factors appear to regulate SGK1 gene expression and kinase activity. Insulin, for example, stimulates SGK1 activity (but not gene transcription) through its effects on phosphatidylinositol-3-kinase and osmotic shock appears to stimulate both SGK1 activity and gene transcription. Hence, SGK1 might integrate the effects of multiple hormonal and nonhormonal regulators of Na(+) transport in tight epithelia and thereby play a key role in volume homeostasis. It is interesting to speculate that SGK1 might be implicated in medical conditions, such as the insulin resistance syndrome, hypertension and congestive heart failure.

Aldosterone induces rapid apical translocation of ENaC in early portion of renal collecting system: possible role of SGK

Aldosterone controls sodium reabsorption and potassium secretion in the aldosterone-sensitive distal nephron (ASDN). Although clearance measurements have shown that aldosterone induces these transports within 30--60 min, no early effects have been demonstrated in vivo at the level of the apical epithelial sodium channel (ENaC), the main effector of this regulation. Here we show by real-time RT-PCR and immunofluorescence that an aldosterone injection in adrenalectomized rats induces alpha-ENaC subunit expression along the entire ASDN within 2 h, whereas beta- and gamma-ENaC are constitutively expressed. In the proximal ASDN portions only, ENaC is shifted toward the apical cellular pole and the apical plasma membrane within 2 and 4 h, respectively. To address the question of whether the early aldosterone-induced serum and glucocorticoid-regulated kinase (SGK) might mediate this apical shift of ENaC, we analyzed SGK induction in vivo. Two hours after aldosterone, SGK was highly induced in all segment-specific cells of the ASDN, and its level decreased thereafter. In Xenopus laevis oocytes, SGK induced ENaC activation and surface expression by a kinase activity-dependent mechanism. In conclusion, the rapid in vivo accumulation of SGK and alpha-ENaC after aldosterone injection takes place along the entire ASDN, whereas the translocation of alpha,beta,gamma-ENaC to the apical plasma membrane is restricted to its proximal portions. Results from oocyte experiments suggest the hypothesis that a localized activation of SGK may play a role in the mediation of ENaC translocation.

The serum- and glucocorticoid-induced kinase is a physiological mediator of aldosterone action

Aldosterone plays a major role in regulating sodium and potassium flux in epithelial tissues such as kidney and colon. Recent evidence suggests that serum- and glucocorticoid-regulated kinase (SGK) is induced by aldosterone and acts as a key mediator of aldosterone action in epithelial tissues. Induction of SGK messenger RNA (mRNA) has previously been shown within 30 min of addition of supraphysiological doses of aldosterone to Xenopus A6 cells and within 4 h in rat kidney in vivo. In this study we determined the time course of SGK induction, at doses of aldosterone in the physiological range, in rat kidney and colon, using Northern and Western blot analyses and in situ hybridization and determined concurrent changes in urinary sodium and potassium excretion by Kagawa bioassay. On Northern blot analysis, SGK mRNA levels were significantly elevated in both kidney and colon 60 min after the injection of aldosterone. SGK protein in late distal colon was significantly elevated 2 and 4 h after aldosterone treatment. In situ hybridization showed SGK mRNA to be induced in renal collecting ducts and distal tubular elements in both cortex and medulla by doses of aldosterone of 0.1 microg/100 g BW or more within 30 min of steroid treatment. Significant changes in urinary composition were similarly seen with an aldosterone dose of 0.1 microg/100 g BW from 90 min after aldosterone injection. The early onset of SGK induction in kidney and colon and the correlation with urinary changes in terms of both time course and dose response suggest that SGK plays an important role in mediating the effects of aldosterone on sodium homeostasis in vivo.

SGK integrates insulin and mineralocorticoid regulation of epithelial sodium transport

The epithelial Na+ channel (ENaC) constitutes the rate-limiting step for Na+ transport across tight epithelia and is the principal target of hormonal regulation, particularly by insulin and mineralocorticoids. Recently, the serine-threonine kinase (SGK) was identified as a rapidly mineralocorticoid-responsive gene, the product of which stimulates ENaC-mediated Na+ transport. Like its close relative, protein kinase B (also called Akt), SGK's kinase activity is dependent on phosphatidylinositol 3-kinase (PI3K), a key mediator of insulin signaling. In our study we show that PI3K is required for SGK-dependent stimulation of ENaC-mediated Na+ transport as well as for the production of the phosphorylated form of SGK. In A6 kidney cells, mineralocorticoid induction of the phosphorylated form of SGK preceded the increase in Na+ transport, and specific inhibition of PI3K inhibited both phosphorylation of SGK and mineralocorticoid-induced Na+ transport. Insulin both augmented SGK phosphorylation and synergized with mineralocorticoids in stimulating Na+ transport. In a Xenopus laevis oocyte coexpression assay, SGK-stimulated ENaC activity was also markedly reduced by PI3K inhibition. Finally, in vitro-translated SGK specifically interacted with the ENaC subunits expressed in Escherichia coli as glutathione S-transferase fusion proteins. These data suggest that SGK is a PI3K-dependent integrator of insulin and mineralocorticoid actions that interacts with ENaC subunits to control Na+ entry into kidney collecting duct cells.

Safety of oral versus intravenous hydration during induction therapy with intravenous foscarnet in AIDS patients with cytomegalovirus infections

We undertook a study to compare the safety of intravenous (i.v.) versus oral hydration to prevent nephrotoxicity associated with the use of foscarnet for induction therapy of cytomegalovirus (CMV) infection in HIV-infected persons. Patients, given foscarnet at a dose of 90 mg/kg every 12 h, were randomized to receive either i.v. or oral hydration. Thirty-seven patients were given i.v. hydration and 44 were given oral hydration. Median duration of therapy for both groups was 17 days. There was no difference between the 2 groups in either serious adverse events or rise of creatinine to > or = 2.0 mg/dl. However, serum creatinine, while generally remained within normal limits, increased more in patients who received oral hydration after 10 days of therapy (significant only by slope analysis, P < 0.05). Although i.v. hydration provided better protection against nephrotoxicity, oral hydration was relatively safe and convenient provided that creatinine clearance (CrCl) is monitored closely.