Fluid Intake Management in Maintenance Hemodialysis Using a Smartphone-Based Application: A Pilot Study

Rationale & Objective

Increased interdialytic weight gain (IDWG) has been associated with increased morbidity and mortality. We evaluated the usefulness and safety of a mobile application (app) that allows patients receiving maintenance hemodialysis to self-monitor their daily fluid intake.

Study Design

Within group comparison before or during intervention.

Setting & Participants

Patients receiving maintenance hemodialysis with mean IDWG of <4%.

Exposure

Participants were trained to use a smartphone-based app, FiApp that allowed them to record fluid intake and compare with individual targeted daily fluid intake determined by the nephrologist.

Outcomes

The primary study outcome was the association between IDWG and fluid intake recorded in the FiApp. Secondary outcomes included FiApp safety and usage. Patient interviews were performed at weeks 1 and 4 to collect information regarding FiApp usability and recommendations for app improvements.

Analytical Approach

Mean, median, and standard deviation.

Results

Eighteen of 25 patients completed the full 4-week study, provided all app data, and completed 2 patient interviews. The mean 4-week IDWG during app use was similar to the baseline mean 4-week IDWG before app use; however, 61% of the participants had a decrease in IDWG when using the app compared with IDWG at baseline. Of the 18 participants who completed the study, only 1 had a mean 4-week IDWG that was 20% higher than that at baseline. The app was used on ≥80% of the days by 13 (72%) of 18 participants, and was used every day in 7 (39%) of 18 participants. The mean relationship between fluid reported in the app and fluid consumed was 40%.

Limitations

This safety study recruited patients who had IDWG of <4%.

Conclusions

A smartphone-based app can be safely used to help patients receiving maintenance hemodialysis track and control fluid intake. Motivated patients were able to decrease IDWG despite baseline IDWG being <4% of the body weight.

Trial Registration

NCT03759847.

Plain-Language Summary

Patients receiving maintenance hemodialysis struggle to limit fluid intake. Excess fluid intake can lead to adverse cardiovascular events. We developed a smartphone app to help patients receiving dialysis self-monitor their fluid intake. In this safety study in patients receiving dialysis with an interdialytic weight gain of <4% of the body weight, more than half of the patients were able to decrease their interdialytic fluid intake while using the app, and only 1 patient had an increase in interdialytic weight gain of >20% while using the app. Information gleaned from structured patient interviews will be used to refine this app.

[A rare familial form of idiopathic pulmonary fibrosis with Poly(A)-specific ribonuclease (PARN) mutation]

New techniques of DNA sequences allow to discover genetics mutations involved in familial pulmonary fibrosis. Among them, the PARN (Poly[A]-specific ribonuclease) mutation. Herein, we report the case of one patient who has pulmonary fibrosis with PARN mutation and the experience of our patient care.

Assessing a Tool for Self-Monitoring Hydration Using Urine Color in Pregnant and Breastfeeding Women: A Cross-Sectional, Online Survey

BACKGROUND

Pregnant and breastfeeding women experience great changes in their total body water content and water dynamics. To support the accretion of total body water during pregnancy and compensate for the water lost through breast milk during breastfeeding, increased adequate intakes (AI) for total water have been established by various health authorities. Despite this widespread advice, several studies suggest that pregnant and breastfeeding women do not meet the AI for total water, suggesting the need to raise women's awareness on the importance of adequate water intake, particularly during pregnancy and breastfeeding, as well as to provide them with a simple means of monitoring their hydration on a day-to-day basis. A urine color (UC) scale recently has been validated for hydration monitoring in pregnant and breastfeeding women.

SUMMARY

We sought to develop a version of a tool based on the UC scale, using only images or illustrations, which could be understood by users of various nationalities and spoken languages. Pregnant and breastfeeding women (n = 1,275) from Brazil, Mexico, and Poland were shown 3 versions of the tool. Understanding, appreciation, simplicity and intent to use were evaluated using a questionnaire consisting of 26 items. Key Messages: Among the 3 versions tested, one tool emerged as the most highly understood (88% spontaneous understanding) and was highly appreciated by users (mean [SD]: 8.40 [2.20] out of 10). There were no differences between countries. Furthermore, 83% reported being very likely to use the tool daily. These results suggest that a simple tool based on the UC scale will help pregnant and breastfeeding women meet the AI for total water.

Diabetic neuropathy increases stimulation threshold during popliteal sciatic nerve block

BACKGROUND

Peripheral nerve stimulation is commonly used for nerve localization in regional anaesthesia, but recommended stimulation currents of 0.3-0.5 mA do not reliably produce motor activity in the absence of intraneural needle placement. As this may be particularly true in patients with diabetic neuropathy, we examined the stimulation threshold in patients with and without diabetes.

METHODS

Preoperative evaluation included a neurological exam and electroneurography. During ultrasound-guided popliteal sciatic nerve block, we measured the current required to produce motor activity for the tibial and common peroneal nerve in diabetic and non-diabetic patients. Proximity to the nerve was evaluated post-hoc using ultrasound imaging.

RESULTS

Average stimulation currents did not differ between diabetic (n=55) and non-diabetic patients (n=52). Although the planned number of patients was not reached, the power goal for the mean stimulation current was met. Subjects with diminished pressure perception showed increased thresholds for the common peroneal nerve (median 1.30 vs. 0.57 mA in subjects with normal perception, P=0.042), as did subjects with decreased pain sensation (1.60 vs. 0.50 mA in subjects with normal sensation, P=0.038). Slowed ulnar nerve conduction velocity predicted elevated mean stimulation current (r=-0.35, P=0.002). Finally, 15 diabetic patients required more than 0.5 mA to evoke a motor response, despite intraneural needle placement (n=4), or required currents ≥2 mA despite needle-nerve contact, vs three such patients (1 intraneural, 2 with ≥2 mA) among non-diabetic patients (P=0.003).

CONCLUSIONS

These findings suggest that stimulation thresholds of 0.3-0.5 mA may not reliably determine close needle-nerve contact during popliteal sciatic nerve block, particularly in patients with diabetic neuropathy.

CLINICAL TRIAL REGISTRATION

NCT01488474.

Alzheimer CSF biomarkers in routine clinical setting

OBJECTIVES

Our work was aimed to evaluate Alzheimer's disease diagnosis improvement using cerebrospinal fluid biomarkers (CSF) in neurological daily practice.

MATERIALS AND METHODS

For this purpose, 150 patients clinically and neurochemically classified as having AD or cognitive impairment with or without other dementia type were included in the study. The following CSF peptides were studied, blindly to the clinical diagnosis: beta-amyloid(1-42) peptide (Aβ(1-42)), Tau (T-tau), threonine-181 hyperphosphorylated tau protein (P-tau(181)), and beta-amyloid(1-40) peptide (Aβ(1-40)). From these measurements, Innotest® Amyloid Tau Index (IATI) was calculated for each patient.

RESULTS

This assessment allowed to separate 83 biochemical profiles of AD and 67 non-Alzheimer's disease (non-AD), both AD and non-AD categories match with clinical data amounting to 73% and 90%, respectively. Among mild cognitive impairment (MCI) patients, CSF biomarkers led to discriminate those who are likely to be AD. We devoted a special section to Aβ(1-40) which is not a routine parameter but can help to confirm a pathological amyloid process as Aβ(1-42)/Aβ(1-40) ratio underlining the real decline of the Aβ(1-42).

CONCLUSIONS

The interest of biomarkers and their ability to solve awkward cases were carefully noticed all the more when a discrepancy between clinical and CSF biological data was involved. The final proposed algorithm allowed to identify pathogenic forms of AD according to the prevailing role of hyperphosphorylated tau or amyloid beta peptide.

Chemokine IP-10: an adjunct marker for latent tuberculosis infection in children

SETTING

Recent reports indicate a role of chemokine inducible protein 10 (IP-10) in Mycobacterium tuberculosis infection substantiated by the detection of elevated levels in plasma and at infection foci in individuals infected with M. tuberculosis.

OBJECTIVE

To evaluate IP-10 as a potential marker for the diagnosis of M. tuberculosis infection in children living in a region of low tuberculosis (TB) prevalence.

DESIGN

IP-10 levels were obtained after whole blood stimulation with M. tuberculosis-specific antigens in 127 children. IP-10 results were evaluated upon gradations of exposure risk to M. tuberculosis and correlation with tuberculin skin test and an interferon-gamma release assay (IGRA).

RESULTS

IP-10 reactivity correlated well to risk of exposure to M. tuberculosis in children. There was a strong correlation between IP-10 and IGRA results. IP-10 responses, unlike interferon-gamma (IFN-gamma), were not age-dependent and detected more positive results in children aged <5 years. In the children with active disease, the IGRA was more sensitive than IP-10 at detecting M. tuberculosis infection.

CONCLUSION

Our findings suggest that IP-10 in combination with IFN-gamma may enhance the diagnostic performance of IGRAs in detecting M. tuberculosis infection, especially in young children.

Expression levels of thymidylate synthase, thymidylate phosphorylase and dihydropyrimidine dehydrogenase in head and neck squamous cell carcinoma: preliminary study

INTRODUCTION

Pharyngo-laryngeal tumors classified as T3-4, N0-3, M0, are conventionally treated by mutilating surgery (total (pharyngo)-laryngectomy). Neo-adjuvant chemotherapy with 5-FU/platinum salt can be proposed in an attempt to preserve the larynx. The level of the response to chemotherapy ranges from 36 to 54% of cases. Thus, a large number of patients receive chemotherapy that is ineffective and not free from adverse effects. Three main enzymes are involved in the metabolism of 5-FU: thymidylate synthase (TS), thymidylate phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD). Several studies suggest that a high level of expression of these three genes correlates with a poor clinical response to 5-FU. The main purpose of our study was to look for a correlation between the levels of expression of the genes for sensitivity to 5-FU (TS, TP, DPD) within the tumor and the clinical response observed after three courses of chemotherapy combining 5-FU/platinum salt in patients presenting with advanced cancer of the pharyngo-larynx.

METHODS

This was a prospective genetic study that had required approval from the Ethics Committee. The main assessment criterion was based on the assessment of the clinical response by an ENT panendoscopy and a cervical CT scan, after three courses of chemotherapy. The expression of the genes was determined by quantitative RT-PCR, using total RNA extracted from tumor biopsies taken during the initial panendoscopy.

RESULTS

The means calculated, in our study, for the three genes of interest (TS, TP, DPD) were lower in the responder group than those in the non-responder group.

DISCUSSION

Our preliminary findings reveal trends that confirm the hypothesis that the lower the level of expression of the sensitivity genes, the better the clinical response to chemotherapy. They now form part of a larger study that is currently in progress.

Expression Levels of Thymidylate Synthase, Thymidylate Phosphorylase and Dihydropyrimidine Dehydrogenase in Head and Neck Squamous Cell Carcinoma: Preliminary Study

Introduction

Pharyngo-laryngeal tumors classified as T3-4, N0-3, M0, are conventionally treated by mutilating surgery (total (pharyngo)-laryngectomy). Neo-adjuvant chemotherapy with 5-FU/platinum salt can be proposed in an attempt to preserve the larynx. The level of the response to chemotherapy ranges from 36 to 54% of cases. Thus, a large number of patients receive chemotherapy that is ineffective and not free from adverse effects. Three main enzymes are involved in the metabolism of 5-FU: thymidylate synthase (TS), thymidylate phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD). Several studies suggest that a high level of expression of these three genes correlates with a poor clinical response to 5-FU. The main purpose of our study was to look for a correlation between the levels of expression of the genes for sensitivity to 5-FU (TS, TP, DPD) within the tumor and the clinical response observed after three courses of chemotherapy combining 5-FU/platinum salt in patients presenting with advanced cancer of the pharyngolarynx.

Methods

This was a prospective genetic study that had required approval from the Ethics Committee. The main assessment criterion was based on the assessment of the clinical response by an ENT panendoscopy and a cervical CT scan, after three courses of chemotherapy. The expression of the genes was determined by quantitative RT-PCR, using total RNA extracted from tumor biopsies taken during the initial panendoscopy.

Results

The means calculated, in our study, for the three genes of interest (TS, TP, DPD) were lower in the responder group than those in the non-responder group.

Discussion

Our preliminary findings reveal trends that confirm the hypothesis that the lower the level of expression of the sensitivity genes, the better the clinical response to chemotherapy. They now form part of a larger study that is currently in progress.

Non-invasive imaging correlates with histological and molecular characteristics of an osteosarcoma model: application for early detection and follow-up of MDR phenotype

BACKGROUND

In an orthotopic rat osteosarcoma model, histological and molecular findings were compared with the results of non-invasive imaging methods to assess disease progression at the primary site, the pattern of metastatic dissemination and the chemoresistance phenotype.

MATERIALS AND METHODS

Primary tumor engraftment, vascularization, growth and metastatic spread were evaluated using 18FDG tomoscintigraphy. Bone neoformation in the primary tumor and metastasis was determined using 18FNa confirmed by classical histological studies. Chemoresistance phenotype was assessed by analysis of MDR1 and MRP1 genes expression compared to 99mTc MIBI imaging.

RESULTS

99mTc MIBI imaging correlated with the overexpression of the MDR1 and MRP1 genes. 18FDG, 18FNa and 99mTc tomoscintigraphies revealed that the pattern of vascularization, bone neoformation and hematogeneous metastatic dissemination in our animal model mimics its human counterpart.

CONCLUSION

Multimodality, non-invasive imaging is a valid surrogate marker of histological and molecular characteristics in an orthotopic osteosarcoma model in immunocompetent rats; it allows extensive in vivo follow-up of osteosarcoma, including longitudinal analysis of chemoresistance.

Tumor endothelial cells are targets for selective therapies: in vitro and in vivo models to evaluate antiangiogenic strategies

Angiogenesis is a complicated process, essential for tumor progression and metastasis. Extensive work has been done to understand the mechanisms of tumor angiogenesis and identify angiogenesis inhibitors. It is now recognised that tumor endothelial cells present different functional and phenotypic characteristics than normal resting endothelial cells. These differences and advances in molecular biology have allowed the development of selective agents targeting tumor endothelial cells as therapeutic approaches for cancer. These new targeted strategies need to be evaluated in relevant models before being transferred from the laboratory bench to the clinic. In vivo tumor models remain a good way to evaluate the effect of these agents on tumor growth and metastasis. Nevertheless, in parallel to the development of tumor angiogenesis inhibitors, in vitro models have been designed to mimic angiogenesis steps and enable the evaluation of these new drugs. In this paper, after reviewing the phenotypic characteristics of tumor endothelial cells that make them easy to target for antiangiogenic therapy, some of the most commonly used in vitro and in vivo models, which enable the evaluation of antiangiogenic agents, are presented and discussed.

Is troponin I gene therapy effective for osteosarcoma treatment? Study on a human-like orthotopic rat model

BACKGROUND

An anti-angiogenesis strategy has been widely recognized as a viable approach to fight cancer and more and more anti-angiogenic factors are continually being identified. Among them, the muscular isoform of Troponin I (TnI) has been described as being a powerful anti-angiogenic agent in vitro as well as in vivo. We investigated the therapeutic efficacy of TnI gene therapy in a human-like orthotopic rat osteosarcoma model.

MATERIALS AND METHODS

In this tumor model, we evaluated whether the administration of the secreted TnI coding sequence complexed to cationic liposomes (named TnITag cDNA/lCLP) could induce a delay in tumor growth and reduce tumor vasculature.

RESULTS

Although TnI specifically inhibited endothelial cell growth in vitro, we were not able to demonstrate any therapeutic efficacy of TnI in the transplantable osteosarcoma model.

CONCLUSION

This lack of efficacy probably resulted from the rapid degradation of recombinant TnI by matrix metalloproteinases, especially MMP2, which are present in large amounts in tumors.

Overexpression of cytosolic glutathione peroxidase (GPX1) delays endothelial cell growth and increases resistance to toxic challenges

Oxidative stress results from the imbalance between reactive oxygen species (ROS) and ROS-scavenging molecules. Among them, cytosolic glutathione peroxidase (GPX1) plays a major role as it reduces a large part of intracellular ROS. Endothelial cells are a barrier for potentially aggressive molecules circulating in the blood stream and, therefore, are often under great oxidative stress. Thus, we investigated the potentially protective effects of GPX1 overexpression in the endothelial cell line, ECV304. We found that chronic GPX1 overexpression delays cell growth without affecting viability or decreasing resistance to hydrogen peroxide-induced oxidative stress. As GPX1 overexpression could drain the cellular reduced glutathione (GSH) pool, we also tested the effects of extracellular GSH supplementation on cell growth. Despite its largely referenced beneficial effects for cells, GSH was toxic for ECV304 cells in a dose-dependent manner but GSH-induced toxicity was reduced in selenium supplemented cultures and completely abolished in ECV304 overexpressing GPX1, compared to control. In summary, GPX1 overexpression delays cell growth and protects them from GSH and H(2)O(2) toxicity.

Activating mutations of the calcium-sensing receptor: management of hypocalcemia

Activating mutations of the calcium-sensing receptor (CaR) can cause isolated hypoparathyroidism. Treatment of hypocalcemia in these patients remains to be optimized, because the use of 1-hydroxylated vitamin D3 derivatives can cause hypercalciuria and nephrocalcinosis. We identified activating CaR mutations in 8 (42%) of 19 unrelated probands with isolated hypoparathyroidism. The severity of hypocalcemic symptoms at diagnosis was independent of age, mutation type, or mode of inheritance but was related to the degree of hypocalcemia; serum Ca was 1.97 +/- 0.08, 1.82 +/- 0.14, and 1.54 +/- 0.22 mmol/liter, respectively, in asymptomatic (n = 7), mildly symptomatic (n = 8), and severely symptomatic patients (n = 6). Hypocalcemia segregated with the CaR mutation, but no phenotype-genotype relationships were identified. Fourteen patients received regular 1-hydroxylated vitamin D3 treatment (mean duration, 7.2 +/- 4.9 yr). Nine had hypercalciuric episodes, which were associated with nephrocalcinosis in eight cases. Serum Ca during treatment predicted hypercalciuria and nephrocalcinosis poorly, because either or both of the latter could develop in hypocalcemic patients. Thus, mutational analysis of the CaR gene should be considered early in the work-up of isolated hypoparathyroidism. Treatment options should be weighed carefully in patients with serum Ca below 1.95 mmol/liter. The risk of nephrocalcinosis during treatment can be minimized by carefully monitoring urinary Ca excretion.

A new vascular sealant (Sealgel) to achieve rapid hemostasis after percutaneous angioplasty in anticoagulated patients: clinical feasibility and preliminary results

The aim of this study was to assess the feasibility of a new vascular sealant (Sealgel) to provide rapid hemostasis in anticoagulated patients after percutaneous transluminal angioplasty (PTA). Sealgel was designed with ancrod (10 mg) and tranexamic acid (80 mg) dissolved in a hyaluronic acid gel (3 ml). Fifty anticoagulated patients (heparin, aspirin, ticlopidin) who underwent PTA of coronary artery were enrolled in the study. Sealgel (3 ml) was delivered under manual compression through a 9-F cannula at the arterial puncture site after the introducer sheath removal at the end of PTA procedure. Hemostasis time as well as complications were recorded. Sealgel was successfully delivered in 98 % of patients. Hemostasis occurred within 15 mn of manual compression in 82 % of patients, within 25 mn in 98 %, and failed in 1 patient (2 %). Hematoma (6-cm diameter) was observed in 1 patient and late bleeding in another one. There were no clinical signs of embolism, inflammatory swelling, local infection, vascular fistula, or pseudoaneurysm. No surgery or blood transfusion was required. Sealgel application after PTA in anticoagulated patient is feasible and secure. Preliminary results suggest that the Sealgel brought about rapid hemostasis; however further studies are needed to determine its clinical efficacy.

Prevalence of the T215Y mutation in human immunodeficiency virus type 1-infected pregnant women in a New York cohort, 1995--1999

From 1997 through 1999, the prevalence of the zidovudine resistance mutation T215Y was 9.7% among pregnant women, and the human immunodeficiency virus type 1 (HIV-1) load in those with resistant virus was higher than that measured in women with wild-type HIV-1. All mutations were noted in women with zidovudine experience, which suggests that monotherapy may not be adequate prophylaxis for vertical transmission of HIV-1 infection in the current era.

The impact of early initiation of highly active antiretroviral therapy on the human immunodeficiency virus type 1-specific CD8 T cell response in children

This cross-sectional study investigated the effect of early highly active antiretroviral therapy (HAART) on human immunodeficiency virus (HIV) type 1-specific CD8 T cell responses in children. HIV-1-specific CD8 T cell responses were quantified using an enzyme-linked immunospot assay to measure interferon-gamma-secreting cells. HIV-1-infected children were classified by time of HAART initiation prior to age 1 year or after age 2 years as early (n=24) or late (n=28) treated. The magnitude and breadth of the HIV-1-specific CD8 T cell response was significantly lower in children receiving early compared with late HAART treatment (P=.0007 and.0001, respectively). However, total CD8 T cell responses in the early HAART treatment group did not differ significantly from those of age-matched non-HAART-treated controls (n=30). Thus, the reduced magnitude and breadth of the HIV-1-specific CD8 T cell response in early HAART-treated children is due to their younger age.

A large homozygous or heterozygous in-frame deletion within the calcium-sensing receptor's carboxylterminal cytoplasmic tail that causes autosomal dominant hypocalcemia

Autosomal dominant hypocalcemia (ADH) can result from heterozygous missense activating mutations of the calcium-sensing receptor (CaSR) gene, a G-protein-coupled receptor playing key roles in mineral ion metabolism. We now describe an ADH kindred of three generations caused by a novel CaSR mutation, a large in-frame deletion of 181 amino acids within its carboxylterminal-tail from S895 to V1075. Interestingly, the affected grandfather is homozygous for the deletion but no more severely affected than heterozygous affected individuals. Functional properties of mutant and wild-type (WT) CaSRs were studied in transiently transfected, fura-2-loaded human embryonic kidney (HEK293) cells. The mutant receptor exhibited a gain-of-function, but there was no difference between cells transfected with mutant complementary DNA alone or cotransfected with mutant and WT complementary DNAs, consistent with the similar phenotypes of heterozygous and homozygous family members. Therefore, this activating deletion may exert a dominant positive effect on the WT CaSR. The mutant receptor's cell surface expression was greater than that of the WT CaSR, potentially contributing to its gain-of-function. This novel mutation in the CaSR gene provides the first known examples of a large naturally occurring deletion within a G-protein-coupled receptor's carboxylterminal-tail and of a homozygous, affected individual with ADH.

Immunologic and virologic responses to HAART in severely immunocompromised HIV-1-infected children

OBJECTIVE

To determine the long-term immunologic and virologic effects of highly active antiretroviral therapy (HAART) in children with AIDS.

DESIGN

A prospective observational study.

SETTING

Two pediatric HIV clinics.

PARTICIPANTS

Twenty-five protease-inhibitor naive HIV-infected children (aged 2-18 years) with advanced disease (CD4 < or =6%).

INTERVENTION

HAART (one protease inhibitor and one or more nucleoside analogs). Diphtheria and tetanus immunization in six patients after 18 months of therapy.

MAIN OUTCOME MEASURES

Changes in percentage of CD4 cells and plasma HIV-1 RNA levels; post-treatment assays of lymphoproliferative responses to recall antigens; CD4 cell memory phenotype.

RESULTS

Median duration of follow-up was 18.8 months (range, 7.5-28 months). At baseline the CD4 cell percentage was 2% (range, 0-6%), this increased significantly to 16% (range, 3-48%) above baseline at 12 months (P = 0.002). The mean maximum CD4 cell increase was 20.7% (range 4-48%) which corresponds to 657x10(6) cells/l (range, 30-2240x10(6) cells/l) above baseline. By contrast, the median viral load was not significantly lower at 12 months than at baseline (P = 0.34), and only 25% of the patients had sustained undetectable viral load. Of the reconstituted CD4 cells 70% were naive, and none of the subjects had lymphoproliferative responses to tetanus and diphtheria although 40% did develop responses to Candida, an environmental antigen. A single immunization with diphtheria and tetanus toxoid produced lymphoproliferative responses to tetanus in three out of six patients.

CONCLUSIONS

HAART was associated with sustained increases in CD4 cell counts, despite a high incidence of 'virologic failure'. CD4 counts and the proportion of naive cells were higher than have been reported in adults, which may be a reflection of greater thymic activity in children. Memory cell clones for antigens encountered in the past which are not prevalent before therapy could not be expanded without additional antigenic exposure.

Arachidonate 15-lipoxygenase of reticulocyte-type in human rheumatoid arthritis type B synoviocytes and modulation of its activity by proinflammatory cytokines

OBJECTIVE

Lipoxygenases (LOX) are lipid-peroxidating enzymes that are implicated in the pathogenesis of a variety of inflammatory disorders such as arthritis, psoriasis, and asthma. 15-LOX catalyzes the oxygenation of free arachidonic acid to 15-hydroperoxy-5,8,11,13-eicosatetraenoic acid (15-HPETE), which is reduced to 15-hydroxyeicosatetraenoic acid (15-HETE). The biological role of 15-HETE is less clear. We sought to determine if cultured human rheumatoid synovial cells were able to express 15-LOX mRNA, leading to the synthesis of 15-HETE, and to examine the effect of different cytokines on 15-LOX activity.

METHODS

Adherent synovial cells were obtained by enzymatic digestion of rheumatoid synovium, isolated from patients with rheumatoid arthritis (RA) undergoing hip synovectomy. Between passages 4 and 8, reticulocyte-type 15-LOX expression in these cells was determined by reverse transcription-polymerase chain reaction (RT-PCR) in situ and confirmed by classical RT-PCR analysis followed by enzymatic digestion. The PCR fragment was purified, amplified, and sequenced. Cultured synovial cells were incubated with or without different cytokines and exogenous [1-(14)C] arachidonic acid metabolism of synoviocytes was analyzed by reverse phase high performance liquid chromatography (RP-HPLC).

RESULTS

RT-PCR results showed that human RA type B synoviocytes expressed a reticulocyte-type 15-LOX. By sequence analysis, the PCR fragment (474 bp) was determined to be 100% identical to that of reticulocyte-type 15-LOX cDNA. Other results associated specific inflammatory cytokines with the activity of 15-LOX in these cells. RP-HPLC analysis showed that interleukin 4 (IL-4) increased 15-HETE production (2.4-fold); we also observed an increase in 15-HETE production (1.2-fold) after incubation of the cells with IL-1beta.

CONCLUSION

Human RA type B synoviocytes are able to express 15-LOX mRNA leading to the synthesis of 15-HETE, which is modulated by various cytokines that play a major role in the pathophysiology of RA, especially IL-4 and IL-1.

Brain "embolism" detected by magnetic resonance imaging during percutaneous mitral balloon commissurotomy

PURPOSE

The common finding of thrombi between the bifoil balloons when they were extracted after mitral dilation prompted us to look for evidence of minor brain embolisms using the sensitive technique of BMRI (brain magnetic resonance T2-weighted imaging).

METHODS

BMRI was performed within 48 hr before and after a percutaneous mitral balloon commissurotomy (PMBC) in each of the 63 patients in this study.

RESULTS

There was evidence (hyperintensity foci: HI) of a previous asymptomatic brain embolism in 38 of 63 patients before PMBC and a new HI appeared in 18 of 63 patients after the procedure. New HI signals were found exclusively in the white matter in 8 of 18 patients and in only 3 of 18 were HI signs larger than 1 cm. One patient, with an HI signal > 1 cm in the thalamus and another < 1 cm in the brain stem, presented diplopia accompanied by other minor clinical signs. The differences in HI rate among four subgroups (1, older vs younger than 43 years; 2, sinus rhythm vs atrial fibrillation; 3, echo score < 8 vs > 8; 4, patients from western countries vs the others) were not statistically significant, probably because the number of patients in each subgroup was low. Patients in atrial fibrillation had slightly more (not significant) HI before PMBC (15/20, 75%) than patients in sinus rhythm (23/43, 53%), but after PMBC their HI frequencies were similar (atrial fibrillation: 5/20, 25%; sinus rhythm: 13/43, 30%).

CONCLUSION

Brain microembolism is frequent during PMBC, but is often anatomically limited and free from clinical signs in most cases. Brain embolism seems to be related mainly to the procedure itself and not the features of the patient.

Selective killing of osteosarcoma cells in culture after retroviral mediated gene transfer of a herpes simplex thymidine kinase suicide gene

As conventional therapy of osteosarcoma is aggressive and its success relatively poor, notably in cases relapse, we investigated the therapeutic effect of retroviral herpes simplex thymidine kinase (HSV1-TK) gene transfer into a human osteosarcoma cell line. Transfected target cells are sensitive to ganciclovir (GCV) (IC50 0.1 microM), and a potent bystander effect, by which cell death can be induced in HSV1-TK negative dividing cells located in the vicinity of HSV1-TK positive ones, is demonstrated. This is significant for clinical applications as no available gene transfer method can achieve 100% transduction to target cells.

Treatment of experimental osteosarcoma tumors in rat by herpes simplex thymidine kinase gene transfer and ganciclovir

Previous results have demonstrated the efficiency of Herpes simplex type 1 thymidine kinase (HSV1-TK) retroviral gene transfer and ganciclovir (GCV) treatment of a human osteosarcoma cell line resulting in the death of the cell population and a proximal bystander effect; therefore, we investigated gene therapy on an in vivo osteosarcoma rat model. For in vivo experiments, small fragments of tumor were grafted onto rats in a paratibial position. Seven days after the graft, packaging cells (psi CRIP-TK and psi CRIP-LLZ) were inoculated into tumor mass, followed by GCV administration. In vivo results showed the efficiency of this system that allowed the reduction of the tumor mass and prevented lung metastasis appearance, which represents the normal evolution. This type of treatment seems promising for rapidly proliferating tumors such as osteosarcoma; the lower IC50 makes this system particularly attractive as clinically doses may be of low magnitude to prevent secondary effects in patients.

Brain "embolism" detected by magnetic resonance imaging during percutaneous mitral balloon commissurotomy

PURPOSE

The common finding of thrombi between the bifoil balloons when they were extracted after mitral dilation prompted us to look for evidence of minor brain embolisms using the sensitive technique of BMRI (brain magnetic resonance T2-weighted imaging).

METHODS

BMRI was performed within 48 hr before and after a percutaneous mitral balloon commissurotomy (PMBC) in each of the 63 patients in this study.

RESULTS

There was evidence (hyperintensity foci: HI) of a previous asymptomatic brain embolism in 38 of 63 patients before PMBC and a new HI appeared in 18 of 63 patients after the procedure. New HI signals were found exclusively in the white matter in 8 of 18 patients and in only 3 of 18 were HI signs larger than 1 cm. One patient, with an HI signal >1 cm in the thalamus and another <1 cm in the brain stem, presented diplopia accompanied by other minor clinical signs. The differences in HI rate among four subgroups (1, older vs younger than 43 years; 2, sinus rhythm vs atrial fibrillation; 3, echo score <8 vs >8; 4, patients from western countries vs the others) were not statistically significant, probably because the number of patients in each subgroup was low. Patients in atrial fibrillation had slightly more (not significant) HI before PMBC (15/20, 75%) than patients in sinus rhythm (23/43, 53%), but after PMBC their HI frequencies were similar (atrial fibrillation: 5/20, 25%; sinus rhythm: 13/43, 30%).

CONCLUSION

Brain microembolism is frequent during PMBC, but is often anatomically limited and free from clinical signs in most cases. Brain embolism seems to be related mainly to the procedure itself and not the features of the patient.

Cyclooxygenase-2 up-regulation after FLAP transfection in human adenocarcinoma cell line HT29 cl.19A

Five-lipoxygenase-activating protein (FLAP) is usually described as an essential protein to activate the leukotriene (LTs) synthesis via the 5-lipoxygenase pathway. In the enterocyte model HT29 cl.19A cell line, 5-lipoxygenase metabolism was found despite the lack of FLAP expression. Therefore HT29 cl.19A represents an original mammalian model to study FLAP-dependent leukotriene synthesis. In FLAP cDNA transfected HT29 cl.19A cells, FLAP expression led to an increase in cyclooxygenase pathway products (mainly PGE2) without an increase in 5-lipoxygenase metabolism. This increase in PGE2 synthesis was associated with a cyclooxygenase-2 upregulation in comparison to untransfected HT29 cl.19A cells. These results suggest a possible interaction between the two major pathways of arachidonic acid metabolism.

Resistance to apoptosis and cyclooxygenase-2 expression in a human adenocarcinoma cell line HT29 CL.19A

BACKGROUND

COX-2 expression increases the tumorigenic potential of enterocytes. Tumorigenic effect is partially linked to an inhibition of programmed cell death which is one of the most important components in maintaining intestinal epithelium integrity.

MATERIALS AND METHODS

We analyzed apoptosis in HT29 cl.19A cells cultured over 3 weeks, in the presence (10%) or in the absence of fetal bovine serum (FBS), by analysis of genomic DNA fragmentation after agarose gel electrophoresis, morphological measurement of apoptosis using DAPI chromatin staining, and transmission electron microscopy (TEM) to identify apoptotic cellular morphological changes.

RESULTS

Regardless of the methods used, no apoptotic signs were observed for each culture condition, even if cells were cultured 3 weeks in the absence of FBS.

CONCLUSION

Using HT29 cl.19A cells (untransfected cells), we found that intrinsic or constitutive COX-2 expression in adenocarcinoma cell line was associated with spontaneous resistance to apoptosis.

Cyclooxygenase-2 expression in human adenocarcinoma cell line HT29 cl.19A

BACKGROUND

Overexpression of cyclooxygenase-2 (COX-2) has been implicated in carcinogenesis of human colorectal cancer which is one of the leading types of cancer in Western countries.

MATERIALS AND METHODS

We analyzed the COX-2 expression and activity using RT-PCR, Western blot, immunocytochemistry, RP-HPLC and EIA analysis in 0% and 10% fetal bovine serum (FBS) cultured cells.

RESULTS

HT 29 cl.19A cells exhibited a COX-2 expression called "constitutive" in the absence of FBS in culture media. This particular expression was not the result of a mutation of the HT29 cl.19A COX-2 gene promotor.

CONCLUSION

In our study, the human colon adenocarcinoma cell line, HT29 cl.19A, expressed COX-2 abnormally. This expression appeared to be at the same time inducible by the action of classical exogenous inducers such as FBS or interleukin-1 beta and "constitutive" if none of these compounds were present.

Brefeldin A-induced apoptosis is expressed in rat neurons with dephosphorylated tau protein

Brefeldin A (BFA) is a fungus metabolite (penicillum brefeldanum) that is known to produce the disintegration of the Golgi apparatus in exposed cells, and apoptosis in various cancer cells. This study reports that in rat primary cortical cell cultures BFA also produces apoptosis assessed by the TUNEL method and DAPI (4',6-diemidino-2-phenylindole) staining. The percentages of apoptotic neurons range from 26.9% +/- 8.3 to 43.2 +/- 2.5% in cultures exposed from 4 to 8 h to BFA (10 microg/ml). A double fluorescent staining, using AT8 antibody (phosphorylated tau) or tau1 antibody (dephosphorylated tau) associated with DAPI labeling reveals that tau1 positive neurons are more sensitive to BFA-induced apoptosis compared to AT8 positive neurons. This result and previous results using other apoptosis inducers suggest that tau phosphorylation in the vicinity of the AT8-tau1 epitopes is a marker of resistance or sensitivity to neuronal apoptosis in rat cortical cell cultures.

Linoleic acid peroxidation by Solanum tuberosum lipoxygenase was activated in the presence of human 5-lipoxygenase-activating protein

The present investigation describes the ability of human 5-lipoxygenase-activating protein (FLAP) to activate a plant 5-lipoxygenase. The presence of an active recombinant human FLAP in the 100000xg membrane fraction of infected Sf9 cells led to a specific increase in 9-hydroperoxyoctadecadienoic acid (9-HPOD) synthesis (+68%) or in 5-hydroperoxyeicosatetraenoic acid (5-HPETE) synthesis (+68%), after action of Solanum tuberosum tuber 5-lipoxygenase (S.t.LOX) on linoleic acid (natural plant lipoxygenase substrate) or on arachidonic acid. On the contrary, the presence of non-transfected membranes obtained from non-infected Sf9 cells led to an inhibition of lipoxygenase activity. MK-886, a potent inhibitor of leukotriene biosynthesis, blocked the FLAP dependent S.t.LOX activation after preincubation with FLAP transfected membranes. In conclusion, this study demonstrates that a recombinant human FLAP can stimulate a lipoxygenase other than mammalian 5-lipoxygenase (S.t.LOX) by using different polyunsaturated fatty acids as substrates.

Variable expression of Mn SOD in three different human melanoma cell lines

In recent studies, decreased expression of Mn SOD, an intramitochondrial enzyme responsible for the dismutation of anion superoxide, has been reported in multiple, malignant cell types, whereas its gene has been proposed as a tumour suppressor gene in melanoma. We studied the expression of Mn SOD both at genetic (DNA, mRNA) and protein levels in three human melanoma cell lines (M3 Da, M4 Be, M1 Do). All cell lines were tumorigenic in a nude mouse model. In these cell lines, Mn SOD was studied at the molecular level using PCR of genomic DNA, and by RT-PCR of total mRNA extracts to detect Mn SOD transcripts. Mn SOD protein expression was studied by indirect immunofluorescence using a monoclonal antibody anti-human Mn SOD (Bender) on suspended cells fixed on slides after cytospin. All three human melanoma cell lines studied contained detectable amounts of DNA and mRNA specific for the Mn SOD gene. In contrast, there was variable expression of Mn SOD at the protein level. As detected by immunofluorescence, Mn SOD protein was expressed in only two cell lines (strongly in M3 Da, weakly in M4 Be) but not in M1 Do. These preliminary, qualitative results demonstrate that the deficit of Mn SOD protein expression is variable depending on the particular melanoma cell line. Further investigations are required in order to evaluate quantitative Mn SOD protein expression and activity as well as the level of functional Mn SOD mRNA and DNA in these or other cell lines.

Methotrexate and cyclooxygenase metabolism in cultured human rheumatoid synoviocytes

OBJECTIVE

Our objective was to characterize the effect of methotrexate (MTX) on prostaglandin E2 (PGE2) synthesis in cultured human rheumatoid synovial cells. Prostaglandins (PG) are important mediators of inflammation and joint destruction in rheumatoid arthritis (RA). Two isoforms of cyclooxygenase (COX), the key enzyme in PG synthesis, have been characterized: a constitutively expressed form, COX-1, and an inducible form, COX-2. The mechanisms of action of low dose MTX in RA treatment are still poorly understood. As the clinical effects are often first noticed within a month of starting MTX therapy, an antiinflammatory action has been proposed.

METHODS

Adherent synovial cells were obtained by collagenase digestion of rheumatoid synovium, isolated from patients with RA undergoing synovectomy. Between passages 3 and 6, cultured synovial cells were incubated with or without MTX for 54 h, at various concentrations. Interleukin (IL)-1beta (1 ng/ml) was added or not for the last 6 h of incubation. Supernatants were harvested and assayed for PGE2 by enzyme immunoassay (EIA). Exogenous [1-14C]arachidonic acid metabolism of synoviocytes was analyzed by reverse phase high performance liquid chromatography (RP-HPLC). COX-1 and COX-2 mRNA expression was determined by total RNA extraction and reverse transcription polymerase chain reaction.

RESULTS

Cellular viability was not affected by MTX. EIA showed that MTX decreased IL-1beta induced PGE2 production by synoviocytes in a dose dependent manner. RP-HPLC analysis confirmed the inhibition of PGE2 and (12S)-12-hydroxy-5,8,10-heptadecatrienoic acid production. COX-1 and IL-1beta induced COX-2 mRNA expression were not inhibited by MTX.

CONCLUSION

MTX has an inhibitory effect on IL-1beta stimulated production of PGE2 by cultured human rheumatoid synoviocytes, without affecting either COX mRNA expression. Among various biochemical and immunologic events, MTX could have an antiinflammatory action by decreasing PGE2 release.

Expression of arachidonate platelet-type 12-lipoxygenase in human rheumatoid arthritis type B synoviocytes

In the present study, we have demonstrated platelet-type 12-lipoxygenase (12-LOX) expression in human rheumatoid arthritis (RA) type B synoviocytes by reverse-transcription polymerase chain reaction (RT-PCR). The presence of 12-LOX mRNA in these cells was revealed by classical RT-PCR analysis using platelet-type 12-LOX cDNA primers and the PCR fragment (246 bp) was purified, amplified and sequenced. By sequence analysis, this fragment was determined to be 100% identical to that from platelet-type 12-LOX cDNA. Immunofluorescence data demonstrate that interleukin-1beta (IL-1beta) increases cellular 12-LOX protein. Other results associate specific inflammatory cytokines with the activity of 12-LOX in human RA type B synoviocytes. IL-1beta increased 12S-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE) production (4-fold) and we also observed an increase in 12-HETE production (2.5-fold) after incubation of human RA type B synoviocytes with TNF alpha. In contrast to the action of IL-1beta on 12-HETE synthesis, IL-4 and IL-6 did not enhance 12-HETE production. This is the first demonstration of platelet-type 12-LOX cDNA derived from the mRNA of cultured human RA type B synoviocytes.

Left main coronary artery compression during primary pulmonary hypertension

Primary pulmonary hypertension (PPH) is often associated with angina-like chest pain, the mechanism of which is controversial. A 37-year-old woman with severe PPH and angina had transient ischemic ECG changes and reversible anterior perfusion defect on 201thallium scintigraphy. Coronary angiography revealed severe stenosis of the left main coronary artery (LMCA) and otherwise normal vessels. After heart-lung transplantation, examination of the explanted heart showed normal coronary arteries. Compression of the LMCA by the dilated pulmonary artery trunk was responsible for myocardial ischemia. This mechanism should be considered in patients with PPH and angina and might contribute to the high sudden death rate.

Molecular characterization of L2 lipoxygenase from maize embryos

We investigated the expression and accumulation pattern of lipoxygenase isoforms throughout the maize plant life. Two forms of lipoxygenase L1 and L2 have been identified as acidic proteins of 100 kDa (pI 6.4) and 90 kDa (pI 5.5-5.7) which accumulate in dry embryos and in various organs of maize seedlings. In young embryos, only the L2 form was detected and accumulation of L2 mRNA decreased during embryo development. Identification of lipoxygenases from in vivo and in vitro synthesized proteins indicates that similar levels of both L1 and L2 forms accumulated during treatment with abscisic acid, (ABA) gibberellic acid (GA3) and jasmonic acid (JA). However, differences in the activity of both enzymes were detected. By using an antiserum directed against purified L2 we isolated and characterized a partial cDNA clone of maize embryos encoding a lipoxygenase. The deduced amino acid sequence of L2 cDNA shares 78% identity with the rice L2 protein, and 51-56% identity with lipoxygenases from the dicotyledonous plants soybean and Arabidopsis. DNA blot analysis indicated that maize contains a family of lipoxygenase genes which are presently being characterized.

Antioxidant activity in bronchoalveolar lavage fluid from patients with lung cancer

Glutathione (GSH) is one of the key components of the lung antioxidant defenses. Chronic smokers have higher GSH concentrations in their epithelial lining fluid than do nonsmokers. The aim of this study was to compare antioxidant concentrations in epithelial lining fluid (ELF) from nonsmokers, smokers with, and smokers without non-small-cell lung cancer. The study found that GSH in ELF from patients with lung cancer was significantly greater than in ELF from smokers and nonsmokers, at 1,485.5 +/- 208, 544 +/- 97.6 microM, and 339.3 +/- 112 microM, respectively (p < 0.05). In contrast, superoxide dismutase (SOD) was lower in ELF from patients with lung cancer than in that from smokers and nonsmokers, at 3.52 +/- 0.99, 30.82 +/- 8.2, and 43.91 +/- 10.1 U/ml, respectively (p < 0.05). Spontaneous superoxide anion release by adherent alveolar macrophages (AM) showed no difference between smokers with and without lung cancer. These data indicate that patients with lung cancer have marked modifications in their ELF antioxidant defenses by comparison with those of smokers. It is difficult to distinguish whether changed antioxidant status is a primary disturbance involved in the cancer process or whether it is a consequence of the neoplastic changes in malignancy.

Development of in vitro biocompatibility assays for surgical material

This work reports the development of a test to evaluate the biologic effects of implant material used in orthopaedics and traumatology based on the examination of inflammation and allergic reactions at the cellular level. The variation in arachidonic acid metabolite production by murine peritoneal macrophage cultures was studied using different powders of implant material. Macrophage activation by zymosan served as a control. Mouse peritoneal macrophages were labeled with 14C-arachidonic acid, and the synthesis of cyclooxygenase products (6-keto-prostaglandin F1 alpha; prostaglandins F2 alpha, E2, D2; and thromboxane B2) and lipoxygenase products (hydroxyeicosatetraenoic acids) was analyzed and quantified by chromatography. Results obtained through these assays support the reported clinical data that chrome and nickel increase the production of hydroxyeicosatetraenoic acids by mouse peritoneal macrophages. HXPATRI, titan oxide, and monoclinic zircon also increase the production of hydroxyeicosatetraenoic acids in contrast to other powders tested (alumina, HXPBL, chrome cobalt alloy, stainless steel 316L, titan, quadratic zircon), which have little effect on the production of arachidonic acid metabolites by the lipoxygenase pathway. It is concluded that determination of arachidonic acid metabolite production by murine peritoneal macrophage cultures is appropriate for evaluating implant material.

Nitric oxide induces cultured cortical neuron apoptosis

A series of experiments were designed to examine the potential induction of apoptosis by nitric oxide (NO) donors on cortical neuronal cell culture. A 24 h exposure of three different NO donors, 3-morpholinosydnonimine, S-nitroso-N-acetyl-penicillamine, and S-nitrosoglutathione, induced apoptosis as indicated by following histological (cellular and nuclear morphology) and biochemical markers (DNA oligonucleosomal fragmentation and protection by protein synthesis inhibitor).

Shortened survival in infants vertically infected with human immunodeficiency virus with elevated p24 antigenemia

OBJECTIVE

To determine whether the amount of p24 antigenemia in the first 6 months of life is a predictor of survival in children infected vertically with human immunodeficiency virus type 1.

METHODS

A retrospective study of vertically infected infants and children who were followed prospectively from early infancy and who had quantitation of plasma p24 antigen concentration in the first 6 months of life. Infants were first stratified by duration of survival as infants who died before 2 years of age (short-term survivors) and infants who survived to 2 years of age (intermediate-term survivors). The median p24 antigen concentration and the proportion of infants in each group with high concentrations of antigen were compared. Analyses with and excluding all p24 determinations made after the use of antiretroviral agents were compared Kaplan-Meier product limit analysis was used to compare survival in infants with low and high antigenemia during the first 6 months of life.

RESULTS

The median p24 antigen concentration in 15 short-term survivors was 228 pg/ml, compared with 14 pg/ml in 26 intermediate-term survivors (p < 0.05). The proportion of children with > 100 pg/ml of p24 was higher in short-term than in intermediate-term survivors (p = 0.01). Survival to 2 years of age in infants in whom all p24 antigen values during the first 6 months of life were 100 pg/ml or less was 91%, in comparison with 39% in infants with values greater than 100 pg/ml (p = 0.0017).

CONCLUSIONS

Elevated p24 antigenemia in the first 6 months of life is associated with shorter survival and may be a useful predictor of outcome.

Lipoxygenase products and expression of 5-lipoxygenase and 5-lipoxygenase-activating protein in human cultured synovial cells

5-Lipoxygenase products are pro-inflammatory mediators. Their roles and cellular origin in chronic inflammatory rheumatisms such as rheumatoid arthritis (RA) are poorly understood. The expression of arachidonate 5-lipoxygenase (5-LOX, arachidonate: oxygen 5-oxydoreductase; EC 1.13.11.34) and the 5-lipoxygenase activating protein (FLAP) genes in osteoarthritis and RA synoviocytes was studied at the transcriptional level by reverse transcription-polymerase chain reaction (RT-PCR) methodology. Arachidonic acid metabolism was analyzed by reverse-phase high pressure liquid chromatography. 5-LOX and FLAP mRNA were detectable using RT-PCR in all sources of synoviocytes tested. The expression of 5-LOX and FLAP mRNA led to the synthesis of 5-LOX metabolites. 12- and 15-LOX activities were also present. These LOX products can participate in inflammatory processes leading to joint destruction in RA.

Localization of 12-lipoxygenase mRNA in cultured oligodendrocytes and astrocytes by in situ reverse transcriptase and polymerase chain reaction

We studied the distribution of 12-lipoxygenase mRNA in glial cells. First, mRNA was detected from cellular extracts by soluble-phase reverse transcriptase-polymerase chain reaction (RT-PCR). Taking into account that cell culture populations could not be 100% homogeneous, we then developed, for the first time, an in situ RT-PCR combined with immunocytochemistry with cell specific markers. Using this procedure we showed that 12-lipoxygenase mRNA was expressed both in mature oligodendrocytes and astrocytes.

Efficacy of primary chemoprophylaxis against Pneumocystis carinii pneumonia during the first year of life in infants infected with human immunodeficiency virus type 1

To evaluate the efficacy of primary chemoprophylaxis in preventing Pneumocystis carinii pneumonia (PCP) in infants with perinatal human immunodeficiency virus-1 infection during the first year of life, we conducted a retrospective chart review of infants with human immunodeficiency virus-1 infection born at New York University Medical Center-Bellevue Hospital Center, in New York. Between March 1989 and March 1993, 24 infants received primary chemoprophylaxis with trimethoprim-sulfamethoxazole in the first year of life and 24 infants did not receive primary prophylaxis. The CD4+ T-lymphocyte counts in the two groups did not differ during the first year of life. The median age at the time of initiation of prophylaxis was 3 months, and the average duration of prophylaxis was 5.5 months. Among the infants who had not received prophylaxis, five cases of PCP were diagnosed at a median age of 5 months; in contrast, no cases of PCP were observed in the infants receiving prophylaxis (log-rank test, p = 0.017). The probability of surviving after 1 year of age was 92% for the children who received prophylaxis and 74% for those who did not (log-rank test, p = 0.035). These data indicate that chemoprophylaxis is highly effective in preventing primary PCP and improving survival time in infants with human immunodeficiency virus-1 infection.

12-lipoxygenase mRNA expression by cultured neurons

12-hydroxy 5,8,14-cis 10-trans eicosatetraenoic acid (12-HETE) and its derivatives are the principal lipoxygenase (Lox) products of the mammalian brain. These metabolites have been proposed to play a key role as second messengers in synaptic transmission and might function as retrograde messengers in learning and memory processes: the long-term potentiation. The exact source(s) of 12-HETE and neuronal implication have not been definitively established. The present work was therefore designed to study 12-Lox mRNA expression in neural cell cultures. Detection of this mRNA from cellular extract was obtained by reverse transcriptase-polymerase chain reaction (RT-PCR) and localization in neurons by in situ RT-PCR. These results argue for 12-Lox neuronal production.

Streptococcus pneumoniae in human immunodeficiency virus type 1-infected children

The purpose of this study was to characterize systemic Streptococcus pneumoniae disease in human immunodeficiency virus type 1 (HIV-1)-infected children. All cases of bacteremia and meningitis caused by S. pneumoniae among children less than 18 years old were collected by review of the Microbiology Laboratory records at the Bellevue Hospital Center during the period August 1, 1978, through July 31, 1993. There were 31 bouts of systemic S. pneumoniae disease in 19 of 235 HIV-1-infected children cared for by the Pediatric Infectious Disease staff and 116 bouts in 113 children not known to be HIV-1-infected. Four of the 19 HIV-1-infected children had multiple episodes of S. pneumoniae bacteremia as compared with 3 of 113 in the general population (P = 0.008). The frequency of serotypes and distribution of infections by season of the year did not differ between the 2 groups. The median ages at the time of the S. pneumoniae infection were 1.8 and 1.1 years for the HIV-1-infected children and the general population of children, respectively, when those children with multiple episodes were included for their initial episode only (P = 0.06). In the HIV-1-infected patients, 10 episodes were associated with pneumonia, 5 with pneumonia and otitis media, 5 with otitis media only, 1 with pneumonia and meningitis, 1 with meningitis only and 1 with periorbital cellulitis; 5 had no apparent focus of infection. One episode of pneumonia was complicated by lung abscess and there were 2 deaths. Most HIV-1-infected patients recovered without significant sequelae, and the clinical course of their systemic infections did not appear to be markedly different than that of healthy children.

Sodium naproxen: concentration and effect on inflammatory response mediators in human rheumatoid synovial fluid

Twelve patients suffering from rheumatoid arthritis and having swollen knees were treated with 1.1 g/day of sodium naproxen administered in one dose, daily for 5 days. The 72-h wash-out period was verified by the absence of any nonsteroidal anti-inflammatory drug using a HPLC screening. Blood and synovial fluid samples were drawn just before treatment and 24 h after the last dose. Eicosanoids (PGE2, 6-keto-PGF1 alpha, TXB2, LTB4, LTC4) in synovial fluid were determined by immunoenzymatic assays. In plasma and synovial fluid, hyaluronic acid was assayed by radiometric assay and sodium naproxen by HPLC. Free drug was determined by equilibrium dialysis. Statistical analysis used nonparametric tests. Pain relief (evaluated on a visual scale), morning stiffness, and scores on the Lee and Ritchie indices all decreased significantly, as did PGE2 and LTB4 concentrations. The decrease in 6-keto-PGF1 alpha and TXB2 was not significant. No significant change was found for LTC4 and hyaluronic acid. Total concentrations of sodium naproxen were equivalent in plasma (16.1 micrograms.ml-1) and synovial fluid (18.9 micrograms.ml-1). Free fractions were significantly higher in synovial fluid (0.14%) than in plasma (0.11%), as shown by binding of the drug to human serum albumin, at various protein concentrations. Interestingly, the clinical efficacy, as shown by decreases in morning stiffness and in the Lee index score, correlated with the free concentration of naproxen in synovial fluid.

Effects of eicosanoid metabolism inhibitors on growth of a human gastric tumour cell line (HGT)

HGT cells are a human gastric cell line derived from a tumour of the stomach. We have investigated the effects of lipoxygenase and cyclooxygenase metabolism inhibitors on HGT cell proliferation, on fatty acid composition of HGT cells and on the incorporation and distribution of arachidonic acid (AA) in HGT lipids. The cyclooxygenase inhibitor aspirin and both cyclooxygenase and the lipoxygenase inhibitor BW 755C suppressed cell proliferation in a concentration-dependent manner. The inhibition of HGT proliferation did not result from a modulation of the fatty acid composition of membrane lipid, which was not affected by treatment with the various inhibitors. Inhibitors of AA metabolism did not alter acylation of exogenous AA into HGT cells nor its subsequent distribution in the lipid and phospholipid species. The role of cyclooxygenase eicosanoids in HGT proliferation is discussed.

Synthesis of monohydroxylated fatty acids from linoleic acid by rat aortic smooth muscle cells and tissues: influence on prostacyclin production

We have investigated whether cellular metabolism of linoleic acid (18:2) can influence prostacyclin (PGI2) production by cultured rat aortic smooth muscle cells (SMC) and tissues. Incubation of rat SMC homogenates with [1-14C]18:2 results in the enzymatic synthesis of [14C]13-HODE (hydroxyoctadecadienoic acid) and to a lesser extent [14C]9-HODE as defined by gas-liquid chromatography-mass spectrometry (GLC-MS). The observed changes, in percent enzymatically synthesized 13-HODE in the presence of indomethacin, aspirin, metyrapone, 15-HPETE (hydroperoxyeicosatetraenoic acid), and NDGA, suggest that it is formed from the PGH (prostaglandin endoperoxide) synthase pathway. Incubation of intact adherent SMC with [14C]linoleic acid demonstrates that the monohydroxylated compounds are predominantly esterified within the membrane phospholipids and not released into the incubation medium. The simultaneous incubation or a short-term preincubation of 18:2 and arachidonic acid (20:4) do not modify the enzymatic profile of 20:4 transformation. By contrast, long-term preincubation of cells with 18:2 or 13-HODE stimulates the transformation of exogenously added [14C]20:4 to [14C]6-keto PGF1 alpha. However, exogenous 13-HODE does not enhance [14C]6-keto PGF1 alpha recovery from [14C]20:4 prelabeled SMCs. Our results demonstrate that 18:2 is a substrate for PGH-synthase in rat aortic SMC and tissues. The 13-HODE formed is essentially esterified in cell phospholipids and remains without any significant effects on the release of [14C]6-keto PGF1 alpha from [14C]20:4 prelabeled SMC.