Randomised, double-blind, placebo controlled pilot study assessing nitroglycerin as a tocolytic

Thirty-three women in preterm labour were randomised in a double-blind fashion to receive either transdermal nitroglycerin (n = 17) or placebo (n = 16). Both groups had significant (P < 0.001) change in the cervix prior to randomisation. The primary outcome measure was delivery within 48 hours of randomisation. Fewer women randomised to nitroglycerin treatment (6/17) were delivered within 48 hours, compared with the placebo treatment (10/16) (RR 0.56, 95% CI 0.27 to 1.19). This pilot study lends support to two case series published that suggest that transdermal nitroglycerin may be promising as a safe, effective means for tocolysis.

Kinetic basis for selective inhibition of cyclo-oxygenases

Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit the formation of prostaglandins by cyclo-oxygenases (COX). The discovery of a second COX isoform (COX-2) associated with inflammation led to agents that selectively inhibit COX-2, e.g. celecoxib. We evaluated the kinetics of inhibition of celecoxib and several NSAIDs. Celecoxib displays classic competitive kinetics on COX-1 (Ki=10-16 microM). An initial competitive interaction with COX-2 can also be discerned with celecoxib (Ki=11-15 microM), followed by a time-dependent interaction leading to potent inhibition, characterized as inactivation (Kinact=0.03-0.5 s-1). Half-maximal inhibition (IC50) using end-point assays reflects the competitive component on COX-1 (IC50=4-19 microM) and the inactivation component on COX-2 (IC50=0.003-0.006 microM). NSAIDs exhibit four distinct modes of COX inhibition based on kinetic behaviour: (1) competitive, e.g. ibuprofen; (2) weak binding, time-dependent, e.g. naproxen, oxicams; (3) tight binding, time-dependent, e.g. indomethacin; (4) covalent, e.g. aspirin. In addition, most NSAIDs display different kinetic behaviour for each isoform. Weakly binding inhibitors show variable behaviour in enzyme assays, with apparent inhibitory activity being markedly influenced by experimental conditions; determination of kinetic constants with this class is unreliable and IC50 values are strongly dependent on assay conditions. Although IC50 determinations are useful for structure/activity analyses, the complex and distinct mechanisms of enzyme inhibition of each COX isoform by the NSAIDs renders comparison of inhibitory activity on COX-1 and COX-2 using IC50 ratios of questionable validity.

Halothane as a neuroprotectant during constant stimulation of the perforant path

PURPOSE

To determine the neuroprotective effects of halothane during constant stimulation of the perforant path.

METHODS

Male Sprague-Dawley rats had electrodes implanted into the perforant path and dentate granule cell layer under halothane anaesthesia (1-2% in oxygen). They were then divided into four groups. In group 1 (n = 9), the perforant path was stimulated at 20 Hz for 2 h under halothane anaesthesia (1-2%). In group 2 (n = 3), the animals were unstimulated but maintained under halothane anaesthesia (1-2%) for 2 h with the electrodes in place. Both groups 1 and 2 had the electrodes removed and were then allowed to recover fully from the anaesthetic. In groups 3 and 4, the electrodes were held in place with dental acrylic. Both of these groups were allowed to recover fully from anaesthesia. In group 3 (n = 3), 24-48 h after recovery from anaesthesia, the perforant path was stimulated at 20 Hz for 2 h. Group 4 (n = 3) received no stimulation. After 14-17 days, the rats were killed, and morphometry and cell counts were performed on the hippocampi from rats in groups 1 and 2.

RESULTS

Cell densities were not significantly different between control (group 2), unstimulated rats, and animals stimulated under halothane anaesthesia (group 1). Stimulation in the unanaesthetised rats resulted in severe neuronal loss in hilus, CA1, and CA3.

CONCLUSIONS

Halothane protects hippocampal neurons against damage induced by constant stimulation of the perforant path.

Changes in homocysteine levels during normal pregnancy

OBJECTIVE

The objective of this study was to determine the changes in total plasma homocysteine concentration that occur during normal pregnancy.

STUDY DESIGN

In this cross-sectional study homocysteine was measured in 155 normal women in the first, second, and third trimesters and in nonpregnant controls. In addition, albumin, serum B12, serum folate, and red blood cell folate concentrations were measured and correlated to homocysteine values.

RESULTS

The mean homocysteine concentration (in micromoles per liter) was 5.6 (95% confidence interval 3.9-7.3) at 8-16 weeks' gestation, 4.3 (95% confidence interval 3.5-5.3) at 20-28 weeks' gestation, 5.5 (95% confidence interval 3.3-7.5) at 36-42 weeks' gestation, and 7.9 (95% confidence interval 6.2-9.6) in the nonpregnant control group. Homocysteine was significantly lower in all 3 trimesters of pregnancy compared with nonpregnant controls (P <.001). Homocysteine levels were directly correlated with albumin levels, which decreased during pregnancy. Homocysteine concentrations were decreased in subjects taking folic acid supplementation.

CONCLUSION

Serum concentrations of homocysteine decrease during pregnancy. This occurs in association with the physiologic fall in albumin during pregnancy, as well as with folic acid supplementation.

Rapid onset transverse myelitis in adolescence: implications for pathogenesis and prognosis

Five adolescents with transverse myelitis were reviewed. All presented with a rapid onset paralysis of the lower limbs and impairment of bladder control. The maximum disability developed between 10 minutes and six hours. There was no history of trauma, asthma, or prodromal illness. Investigations failed to demonstrate a vascular cause. Extensive spinal cord abnormalities were observed on magnetic resonance imaging. Electrophysiological investigations, performed in four cases, were all consistent with anterior horn cell damage. In all five adolescents there was poor recovery. The underlying pathogenesis of this rapid onset condition remains a subject of debate. Similarities with both transverse myelitis and fibrocartilaginous emboli are evident, widening the spectrum of conditions within the transverse myelitis umbrella. These observations suggest that in rapid onset "transverse myelitis" the combination of extensive hyperintensity on spinal cord neuroimaging with electrophysiological evidence of anterior horn cell involvement might have adverse prognostic significance.

HIV-1MN recombinant glycoprotein 160 vaccine-induced cellular and humoral immunity boosted by HIV-1MN recombinant glycoprotein 120 vaccine. National Institute of Allergy and Infectious Diseases AIDS Vaccine Evaluation Group

We evaluated prime-boost immunization with two recombinant envelope glycoprotein subunit vaccines (HIV-1MN recombinant gp160 vaccine in alum adjuvant [MN rgp160] and HIV-1MN recombinant gp120 vaccine in alum adjuvant [MN rgp120]) for safety and immunogenicity in healthy, HIV-1-uninfected adults. The rationale was to combine the helper T cell memory and binding antibody responses typically induced by rgp160 vaccines with the superior neutralizing antibody responses induced by rgp120 vaccines. In a double-blinded, controlled trial, volunteers were randomly assigned to receive MN rgp160 or adjuvant placebo, and a subset later received MN rgp120. The two vaccines were safe, but reactions to MN rgp160 and its adjuvant placebo exceeded those to MN rgp120. MN rgp160 induced IgG binding antibodies, including all IgG subclasses, to MN rgp160 in all vaccine recipients. HIV-1MN-neutralizing and anti-V3 MN peptide-binding antibodies were observed in a majority of volunteers after the fourth MN rgp160 immunization, but at lower levels compared with immunization with MN rgp120 in historical controls. HIV-1-binding, neutralizing, and fusion inhibition antibodies were boosted to the highest levels among MN rgp160 recipients after MN rgp120 booster injections. MN rgp120 boosting appeared to alter the distribution of MN rgp160 vaccine-induced, anti-MN rgp160 IgG subclass antibodies. MN rgp160 induced helper T cell memory, measured by lymphocyte proliferation, Thl and Th2 cytokine production, and skin testing. Strategies including both subunit vaccines may help maximize antibody and helper T cell memory responses to HIV-1 envelope glycoprotein.

Immune responses to human immunodeficiency virus (HIV) type 1 induced by canarypox expressing HIV-1MN gp120, HIV-1SF2 recombinant gp120, or both vaccines in seronegative adults. NIAID AIDS Vaccine Evaluation Group

A safety and immunogenicity trial was conducted in vaccinia-immune and vaccinia-naive human immunodeficiency virus (HIV)-uninfected adults who were randomized to receive 10(6) or 10(7) TCID50 of canarypox (ALVAC) vector expressing HIV-1MN gp160 or 10(5.5) TCID50 of ALVAC-rabies virus glycoprotein control at 0 and 1 or 2 months and ALVAC-gp160 or 50 microg of HIV-1SF2 recombinant (r) gp120 in microfluidized emulsion at 9 and 12 months; others received rgp120 at 0, 1, 6, and 12 months. All vaccines were well-tolerated. Neither vaccinia-immune status before vaccination nor ALVAC dose affected HIV immune responses. HIV-1MN and HIV-1SF2 neutralizing antibodies were detected more often (100%) in ALVAC-gp160/rgp120 recipients than in recipients of ALVAC-gp160 (<65%) or rgp120 (89%) alone. ALVAC-gp160/rgp120 also elicited more frequent HIV V3-specific and fusion-inhibition antibodies, antibody-dependent cellular cytotoxicity, lymphoproliferation, and cytotoxic CD8+ T cell activity than did either vaccine alone. Trials with ALVAC expressing additional HIV components and rgp120 are underway.

The epidemiology and management of status epilepticus

Status epilepticus refers to a prolonged seizure state, usually taken as lasting 30 min or longer. This review considers recent studies of the epidemiology of status epilepticus; these have confirmed the high incidence and the high associated mortality and morbidity. Advances in the management of status epilepticus are also reviewed but despite these advances there is still a lack of good comparative studies on which to base treatment regimens.

Comparison of single- and repeated-dose pharmacokinetics of diazepam

PURPOSE

To determine whether repeat boluses of diazepam (DZP) lead to significant accumulation in the central nervous system and/or peripheral compartments, as repeat intravenous boluses of diazepam are commonly used in the treatment of status epilepticus (SE).

METHODS

In a rat model that permits simultaneous serum and cerebrospinal fluid (CSF) sampling, we characterized the pharmacokinetics of DZP and its metabolite, desmethyldiazepam, in CSF and blood using HPLC. DZP was administered by intraperitoneal injection as either a single dose (20 or 30 mg/kg) or repeat doses (10 or 20 mg/kg x 3, 1 h apart).

RESULTS

After a single intraperitoneal dose, DZP was rapidly absorbed with a time to maximum concentration of 10 min. The serum concentrations then declined biexponentially. DZP rapidly entered the CSF, the CSF to serum ratio reached equilibrium within 10 min, and was equivalent to the ratio of free to total serum concentration. Repeated DZP dosing resulted in a threefold decrease in volume of distribution and clearance (p < 0.001). This was reflected in the CSF concentration data; however, after the third dose, the ratio of CSF to serum concentration, also increased greatly, representing further persistence of DZP in the CSF compartment.

CONCLUSIONS

Repeat dosing of DZP leads to substantial accumulation, and high, persistent serum and CSF concentrations, which may explain the toxic effects of repeat DZP dosing. Repeat dosing of DZP using a tapering protocol, however, may increase the effectiveness of DZP in treating SE by preventing relapses without substantially increasing toxicity.

Modulation of immunologic responses to HIV-1MN recombinant gp160 vaccine by dose and schedule of administration. National Institute of Allergy and Infectious Diseases AIDS Vaccine Evaluation Group

The safety and immunogenicity of HIV-1MN recombinant gp160 (MN rgp160) vaccine in healthy, uninfected volunteers was tested in a double-blind study with a factorial design. By random assignment, 20 volunteers received three 200 micrograms doses of MN rgp160 and four volunteers received placebo at days 0, 28, and 168 or 0, 56, and 224. Of the 24 volunteers, 16 received 200 micrograms or 800 micrograms of MN rgp160 and two received placebo at day 532 (month 18). The vaccine was safe. It induced T cell memory measured by Th1 cytokine production and lymphocyte proliferation, and serum anti-MN rgp160 IgG (all subclasses) and IgA antibodies. Fifteen of 20 vaccinees developed neutralizing antibody. The regimen including immunizations on days 0, 28, and 168 followed by the 800 micrograms fourth dose was most immunogenic.

Difficulties in extrapolating from clinical trial data to clinical practice: the case of antiepileptic drugs

Effective new antiepileptic drugs (AEDs) are needed for the treatment of those with refractory epilepsy. However, with the growing number of these drugs being licensed and marketed, a rational approach to the treatment of epilepsy is becoming essential. New AED trials can determine appropriate use of AEDs but ultimately fail to determine the best use of AEDs and their exact role in treating patients. New AED trials rarely use clinically applicable measures of efficacy, and it is difficult to extrapolate the data from populations used in AED trials to the wider population of patients with epilepsy. Furthermore, AED trials ignore the factors that are most likely to determine prognosis: the etiology, seizure types, and epilepsy syndrome. To resolve these issues, we need large multicenter studies in well-defined populations with well-characterized seizures, epilepsy syndromes, and etiologies. Being seizure free should be the primary measure of efficacy rather than meta-analyses and guidelines based upon incomplete data.

Changes in activated protein C resistance during normal pregnancy

OBJECTIVE

The objective of this study was to determine the changes in activated protein C resistance that occur during normal pregnancy.

STUDY DESIGN

In this cross-sectional study activated protein C was measured in 128 women with normal pregnancies in the first, second, and third trimesters and in nonpregnant control subjects with 24 to 39 women in each group. In addition, factor V, factor VIII, free protein S, and functional protein C were measured and correlated with activated protein C levels. Polymerase chain reaction for factor V Leiden mutation was performed.

RESULTS

There was a significant fall in the activity of activated protein C in the second and third trimesters of pregnancy (p < 0.05). This was related to increased factor VIII and decreased free protein S levels (p = 0.002, R2 = 0.20). The prevalence of the factor V Leiden mutation was 7.3%.

CONCLUSION

Resistance to activated protein C is increased in the second and third trimesters of pregnancy. This is related to the alterations in other coagulation proteins, a phenomenon normally occurring during pregnancy.

Antibody to human immunodeficiency virus type 1 (HIV-1) gp160 in mucosal specimens of asymptomatic HIV-1-infected volunteers parenterally immunized with an experimental recombinant HIV-1 IIIB gp160 vaccine. The National Institute of Allergy and Infectious Diseases-sponsored AIDS Vaccine Evaluation Group

Twenty-two human immunodeficiency virus type 1 (HIV-1)-infected, asymptomatic volunteers with CD4 cell counts of >600 cells/mm3 who were enrolled in a phase I immunotherapy trial comparing two schedules of immunization of an HIV-1 IIIB-based recombinant gp160 (rgp160) experimental vaccine were evaluated for rgp160-specific antibodies in parotid saliva, genital secretions, and serum. When the study was unblinded, it was determined that five volunteers had received rgp160 on a month 0, 1, 2, 3, 4, and 5 immunization schedule, seven volunteers had received rgp160 on a month 0, 1, 2, and 5 schedule, five had received alum/deoxycholate placebo, and seven had received a licensed hepatitis B virus vaccine. Five volunteers consented to the donation of parotid saliva but not genital secretions. Prior to immunization, parotid saliva specimens were available for 11 of 22 volunteers, seminal plasma (SP) specimens were available for 7 of 22 volunteers, cervicovaginal lavage (CVL) specimens were available for 5 of 22 volunteers, and serum was available for 22 of 22 volunteers. These baseline specimens and specimens collected at 1 and 7 months after the final immunizations were assessed by enzyme-linked immunosorbent assay for immunoglobulin G (IgG) and IgA antibodies specific for HIV-1 LAI rgp160 or HIV-1 MN rgp160. No augmentation in HIV rgp160-specific IgG or IgA antibody production in either parotid saliva or serum specimens of vaccinees compared to that in controls was observed after immunization. There were insufficient numbers of SP or CVL specimens available for statistical comparisons between vaccinees and controls. Overall, anti-LAI rgp160 IgG antibodies were detected in the parotid saliva specimens of 20 of 22 volunteers, the seminal plasma specimens of 11 of 11 volunteers, and the CVL specimens of 6 of 6 volunteers and in 21 of 22 serum specimens. Fewer volunteers expressed anti-LAI rgp160 IgA antibodies in mucosal or serum specimens: 11 of 22 parotid saliva specimens, 3 of 11 SP specimens, 3 of 5 CVL samples, and 12 of 22 sera.

Neutralization of a clade B primary isolate by sera from human immunodeficiency virus-uninfected recipients of candidate AIDS vaccines

The inability of antibodies induced by experimental human immunodeficiency virus type 1 (HIV-1) vaccines to neutralize HIV-1 primary isolates may be due to a failure to elicit such antibodies, antigenic differences between the vaccine and the strains tested, insensitivity of the assays used, or to a combination of factors. New neutralization assays were used to determine the ability of candidate AIDS vaccines to generate neutralizing antibodies for clade B primary isolate BZ167, which is closely related in portions of its envelope to the immunizing strains. Sera from HIV-uninfected volunteers in vaccine trials were tested, and neutralizing activity was found in recipients of recombinant (r) gp120MN or of rgp160MN-containing canarypox boosted with rgp120SF-2. Detection of antibodies that neutralize primary isolate BZ167 correlated with neutralizing activity for homologous vaccine strains. These data demonstrate that certain candidate AIDS vaccines can elicit antibodies that neutralize a primary isolate of HIV-1.

New aromatic inhibitors of EPSP synthase incorporating hydroxymalonates as novel 3-phosphate replacements

A new, aromatic analogue of the EPSP synthase enzyme reaction intermediate 1 has been identified, which contains a 3-hydroxymalonate moiety in place of the usual 3-phosphate group. This simplified inhibitor was readily prepared in five steps from ethyl 3,4-dihydroxybenzoate. The resulting tetrahedral intermediate mimic 9 is an effective, competitive inhibitor versus S3P with an apparent Ki of 0.57 +/- 0.06 microM. This result demonstrates that 3-hydroxymalonates exhibit potencies comparable to aromatic inhibitors containing the previously identified 3-malonate ether replacements and can thus function as suitable 3-phosphate mimics in this system. These new compounds provide another example in which a simple benzene ring can be used effectively in place of the more complex shikimate ring in the design of EPSP synthase inhibitors. Furthermore, the greater potency of 9 versus the glycolate derivative 10 and the 5-deoxy-analog 11, again confirms the requirement for multiple anionic charges at the dihydroxybenzoate 5-position in order to attain effective inhibition of this enzyme.

Diagnosis and treatment of status epilepticus on a neurological intensive care unit

Status epilepticus refractory to first-line therapy is associated with a high morbidity and mortality. Correct diagnosis and adequate treatment of this condition require electrographic monitoring and anaesthetic facilities available in specialist intensive care units (ICUs). We carried out an audit of 26 patients admitted to a neurological ICU with a diagnosis of status epilepticus, to identify deficiencies in diagnosis and management prior to transfer to the ICU, and examine the effectiveness of ICU management. Or transfer, only 14 (54%) were in status epilepticus; six were in drug-induced coma or were encephalopathic, and six had pseudostatus epilepticus, of whom four had been intubated. The commonest treatments prior to transfer were benzodiazepines, chlormethiazole and phenytoin; the loading dose of phenytoin was adequate in at least 7/16 cases. All those in status epilepticus on transfer had their seizures successfully controlled, but ten required general anaesthesia with thiopentone, propofol, ketamine or midazolam. Two died--one had a severe encephalitis and the other had had a cardiac arrest prior to treatment. This study highlights deficiencies in the initial diagnosis and management of status epilepticus, the role of specialist neurological intensive care, and the importance of early referral.

New antiepileptic drug trials in developing countries: are they necessary?

In recent times, antiepileptic drug (AED) development has expanded with at least seven new AEDs being marketed in a variety of countries. However, in this same period there have been very few trials of new AEDs in the developing world where the majority of people with epilepsy reside. There are many problems with the extrapolation of results from AED trials in developed countries, thus underlining the need for new AED trials in developing countries. This, however, presents a number of ethical and logistical problems, as the majority of people with epilepsy in developing countries are inadequately treated with established drugs. Additionally, there are further problems involving the cost of treatment and the allocation of sparse resources. If trials of new AEDs are to take place in developing countries, strict ethical guidelines must be adhered to, the trials must not be purely marketing exercises, and there must be the continued availability of the new AED to those in the trials who have benefited.

Topiramate: a new antiepileptic drug for refractory epilepsy

Topiramate is a recently licensed and marketed antiepileptic drug in the UK for use as add-on therapy for refractory partial epilepsy. It has multiple modes of action involving voltage-dependent sodium channels, GABA receptors and glutamate receptors. Topiramate has very favourable pharmacokinetics as it is primarily excreted unchanged. Its metabolism is, however, increased by enzyme inducers, and it can inhibit the metabolism of phenytoin in some patients. Its efficacy as adjunctive treatment in refractory partial epilepsy in adults appears good, over 40% of patients have a 50% or greater reduction in seizure frequency when topiramate is added to their regime with up to 7% becoming seizure free. The main adverse events are ataxia, impaired concentration, confusion, dizziness, fatigue, parasthesia, somnolence and "thinking abnormal'. Most of these occurred during rapid titration. During long-term treatment, weight loss also occurred and nephrolithiasis occurred in 1.5% of patients receiving topiramate. Topiramate is a useful and well-tolerated addition to our treatment of refractory epilepsy, but it should be titrated slowly in order to avoid adverse events.

Microdialysis study of the neuropharmacokinetics of phenytoin in rat hippocampus and frontal cortex

Acute administration of phenytoin (PHT) is used in the treatment of status epilepticus, yet little is known about the neuropharmacokinetics of PHT in brain extracellular fluid (ECF), the pharmacodynamically relevant compartment. To characterize the neuropharmacokinetics of brain ECF PHT we implanted microdialysis probes in rat hippocampus and frontal cortex and placed a catheter in the internal jugular vein. PHT (50 or 100 mg/kg intraperitoneally, i.p.) was then administered, and microdialysate and serum samples were collected. PHT was rapidly absorbed, with a time to maximum concentration (Tmax) of approximately 20 min for serum concentrations. PHT rapidly entered the brain ECF compartment, with Tmax values similar to those of serum. In brain ECF, PHT concentrations then plateaued for 40-60 min despite decreasing serum concentrations. The area under the brain ECF concentration-time curve (AUC) was higher in hippocampus than frontal cortex. The possible mechanisms for these observations include entry of PHT into specific brain areas both across capillaries and through the cerebrospinal fluid (CSF), extensive binding of PHT in brain white matter, and differing blood flow in different brain regions.

An EPSP synthase inhibitor joining shikimate 3-phosphate with glyphosate: synthesis and ligand binding studies

A novel EPSP synthase inhibitor 4 has been designed and synthesized to probe the configurational details of glyphosate recognition in its herbicidal ternary complex with enzyme and shikimate 3-phosphate (S3P). A kinetic evaluation of the new 3-dephospho analog 12, as well as calorimetric and (31)P NMR spectroscopic studies of enzyme-bound 4, now provides a more precise quantitative definition for the molecular interactions of 4 with this enzyme. The very poor binding, relative to 4, displayed by the 3-dephospho analog 12 is indicative that 4 has a specific interaction with the S3P site. A comparison of Ki(calc) for 12 versus the Ki(app) for 4 indicates that the 3-phosphate group in 4 contributes about 4.8 kcal/mol to binding. This compares well with the 5.2 kcal/mol which the 3-phosphate group in S3P contributes to binding. Isothermal titration calorimetry demonstrates that 4 binds to free enzyme with an observed Kd of 0.53 +/- 0.04 microM. As such, 4 binds only 3-fold weaker than glyphosate and about 150-fold better than N-methylglyphosate. Consequently, 4 represents the most potent N-alkylglyphosate derivative identified to date. However, the resulting thermodynamic binding parameters clearly demonstrate that the formation of EPSPS x 4 is entropy driven like S3P. The binding characteristics of 4 are fully consistent with a primary interaction localized at the S3P subsite. Furthermore, (31)P NMR studies of enzyme-bound 4 confirm the expected interaction at the shikimate 3-phosphate site. However, the chemical shift observed for the phosphonate signal of EPSPS x 4 is in the opposite direction than that observed previously when glyphosate binds with enzyme and S3P. Therefore, when 4 occupies the S3P binding site, there is incomplete overlap at the glyphosate phosphonate subsite. As a glyphosate analog inhibitor, the potency of 4 most likely arises from predominant interactions which occur outside the normal glyphosate binding site. Consequently, 4 is best described as an S3P-based substrate-analog inhibitor. These combined results corroborate the previous kinetic model [Gruys, K. J., Marzabadi, M. R., Pansegrau, P. D., & Sikorski, J. A. (1993) Arch. Biochem. Biophys. 304, 345-351], which suggested that 4 interacts well with the S3P subsite but has little, if any, interaction at the expected glyphosate phosphonate or phosphoenolpyruvate-Pi subsites.