Long term quality of life outcomes following surgical resection alone for benign paediatric intracranial tumours

PURPOSE

Survivors of paediatric intracranial tumours are at increased risk of psychosocial, neuro-developmental, and functional impairment. This study aimed to evaluate long-term health-related quality-of-life (HRQOL) outcomes in patients with benign paediatric brain tumours treated curatively with surgical resection alone.

METHODOLOGY

This was a cross-sectional study of patients with benign paediatric intracranial tumours managed with surgery alone between 2000 and 2015. Eligible patients with a minimum of 5-years follow-up after surgery were identified. Validated health-related quality of life (HRQOL) questionnaires were administered: SF-36, QLQ-BN20, QLQ-C30 and PedsQL™.

RESULTS

Twenty-three patients participated (median age at surgery 13 years; range 1-18; 12 male). The most common diagnosis was pilocytic astrocytoma (n = 15). Median time from surgery to participation was 11 years(range 6-19). Fourteen patients achieved A-level qualifications and two obtained an undergraduate degree. Twelve patients were employed, eight were studying and three were unemployed or volunteering. HRQOL outcomes demonstrated significant limitation from social functioning (p = 0.03) and cognitive functioning (p = 0.023) compared to the general population. Patients also experienced higher rates of loss of appetite (p = 0.009) and nausea and vomiting (p = 0.031). Ten patients were under transitional teenager and young-adult (TYA) clinic follow-up. TYA patients achieved higher levels of education (p = 0.014), were more likely to hold a driver's license (p = 0.041) compared to patients not followed-up through these services.

CONCLUSIONS

Childhood brain-tumour survivors have a greater risk of developing psychological, neuro-cognitive and physical impairment. Early comprehensive assessment, specialist healthcare and TYA services are vital to support these patients.

Presentation, management, and outcomes of cauda equina syndrome up to one year after surgery, using clinician and participant reporting: A multi-centre prospective cohort study

Background

Cauda equina syndrome (CES) results from nerve root compression in the lumbosacral spine, usually due to a prolapsed intervertebral disc. Evidence for management of CES is limited by its infrequent occurrence and lack of standardised clinical definitions and outcome measures.

Methods

This is a prospective multi-centre observational cohort study of adults with CES in the UK. We assessed presentation, investigation, management, and all Core Outcome Set domains up to one year post-operatively using clinician and participant reporting. Univariable and multivariable associations with the Oswestry Disability Index (ODI) and urinary outcomes were investigated.

Findings

In 621 participants with CES, catheterisation for urinary retention was required pre-operatively in 31% (191/615). At discharge, only 13% (78/616) required a catheter. Median time to surgery from symptom onset was 3 days (IQR:1–8) with 32% (175/545) undergoing surgery within 48 h. Earlier surgery was associated with catheterisation (OR:2.2, 95%CI:1.5–3.3) but not with admission ODI or radiological compression. In multivariable analyses catheter requirement at discharge was associated with pre-operative catheterisation (OR:10.6, 95%CI:5.8–20.4) and one-year ODI was associated with presentation ODI (r = 0.3, 95%CI:0.2–0.4), but neither outcome was associated with time to surgery or radiological compression. Additional healthcare services were required by 65% (320/490) during one year follow up.

Interpretation

Post-operative functional improvement occurred even in those presenting with urinary retention. There was no association between outcomes and time to surgery in this observational study. Significant healthcare needs remained post-operatively.

Funding

DCN Endowment Fund funded study administration. Castor EDC provided database use. No other study funding was received.

Usability of Mixed Reality in Awake Craniotomy Planning

AIMS

This study aimed to describe our institutional use of a commercially available mixed reality viewer within a multi-disciplinary planning workflow for awake craniotomy surgery and to report an assessment of its usability.

METHOD

Three Tesla MRI scans, including 32-direction diffusion tensor sequences, were reconstructed with BrainLab Elements auto-segmentation software. Magic Leap mixed reality viewer headsets were registered to a shared virtual viewing space to display image reconstructions. System Usability Scale was used to assess the usability of the mixed reality system.

RESULTS

The awake craniotomy planning workflow utilises the mixed reality viewer to facilitate a stepwise discussion through four progressive anatomical layers; skin, cerebral cortex, subcortical white matter tracts and tumour with surrounding vasculature. At each stage relevant members of the multi-disciplinary team reviewed key operative considerations, including patient positioning, cortical and subcortical speech mapping protocols and surgical approaches to the tumour. The mixed reality system was used in 10 consecutive awake craniotomy procedures over a 5-month period. Ten participants (2 Anaesthetists, 5 Neurosurgical trainees, 2 Speech therapists, 1 Neuropsychologist) completed System Usability Scale assessments, reporting a mean score of 71.5. Feedback highlighted the benefit of being able to rehearse important steps in the procedure, including patient positioning and anaesthetic access and visualising the testing protocol for cortical and subcortical speech mapping.

CONCLUSION

This study supports the use of mixed reality for multi-disciplinary planning for awake craniotomy surgery, with an acceptable degree of interface usability. We highlight the need to consider the requirements of non-technical, non-neurosurgical team members when involving mixed reality activities.

Long Term Quality of Life Outcomes Following Surgical Resection Alone for Benign Paediatric Intracranial Tumours

AIMS

Survivors of paediatric intracranial malignancies are at increased risk of psychosocial, neuro-developmental and functional impairment, important measures of patients’ well-being. This study aimed to evaluate long-term quality of life outcomes (QOL) in patients with benign paediatric brain tumours treated curatively with surgical resection alone.

METHOD

Cross-sectional cohort study of benign paediatric intracranial tumours managed with surgery alone between 2000-2015. Validated QOL questionnaires were administered: SF-36, QLQ-BN20, QLQ-C30 and PedsQLTM.

RESULTS

Twenty-three patients participated (median age at surgery 13 years; range 1-18), twelve were male. The most common diagnosis was pilocytic astrocytoma (n=15). Median time from surgery to participation was 11 years (range 6-19). Fourteen patients achieved A-level qualifications and two obtained an undergraduate degree. Twelve patients were employed, eight were studying and three were unemployed or volunteering. Twelve patients were currently driving. QOL outcomes demonstrated significant limitation from social functioning (p=0.03) and cognitive functioning (p=0.023) compared to the general population norms. Patients also experienced increased loss of appetite (p=0.009) and symptoms of nausea and vomiting (p=0.031). Ten patients were under transitional teenager and young-adult (TYA) clinic follow-up. TYA patients achieved higher levels of education (p=0.014), were more likely to hold a driver’s license (p=0.041) and had improved physical functioning (p=0.005) compared to patients not transitioned through these services.

CONCLUSION

Childhood brain-tumour survivors are particularly vulnerable and at greater risk of developing psychological, neuro-cognitive, socialisation and physical development challenges. Early identification, comprehensive assessment and specialist TYA cancer healthcare input are vital to support these patients and improve their quality of life.

Pulmonary Delivery of Therapeutic and Diagnostic Gases

The 21st Congress for the International Society for Aerosols in Medicine included, for the first time, a session on Pulmonary Delivery of Therapeutic and Diagnostic Gases. The rationale for such a session within ISAM is that the pulmonary delivery of gaseous drugs in many cases targets the same therapeutic areas as aerosol drug delivery, and is in many scientific and technical aspects similar to aerosol drug delivery. This article serves as a report on the recent ISAM congress session providing a synopsis of each of the presentations. The topics covered are the conception, testing, and development of the use of nitric oxide to treat pulmonary hypertension; the use of realistic adult nasal replicas to evaluate the performance of pulsed oxygen delivery devices; an overview of several diagnostic gas modalities; and the use of inhaled oxygen as a proton magnetic resonance imaging (MRI) contrast agent for imaging temporal changes in the distribution of specific ventilation during recovery from bronchoconstriction. Themes common to these diverse applications of inhaled gases in medicine are discussed, along with future perspectives on development of therapeutic and diagnostic gases.

Discovery of a Potent, Selective T-type Calcium Channel Blocker as a Drug Candidate for the Treatment of Generalized Epilepsies

We report here the discovery and pharmacological characterization of N-(1-benzyl-1H-pyrazol-3-yl)-2-phenylacetamide derivatives as potent, selective, brain-penetrating T-type calcium channel blockers. Optimization focused mainly on solubility, brain penetration, and the search for an aminopyrazole metabolite that would be negative in an Ames test. This resulted in the preparation and complete characterization of compound 66b (ACT-709478), which has been selected as a clinical candidate.

UHMS HBO₂ committee chair questions FDA on incorrect info

NOTE: The following clarification letter to the Food and Drug Administration was created at the behest of UHMS President Dr. Enoch Huang, who asked HBO2 Committee Chair Dr. Richard Moon to address erroneous information regarding the risks of hyperbaric oxygen therapy posted on the FDA website.

Milestones to the Discovery of T-type Calcium Channel Blockers for the Treatment of Generalized Epilepsies

We describe the discovery and optimization of new, brain-penetrant T-type calcium channel blockers. We present optimized compounds with excellent efficacy in a rodent model of generalized absence-like epilepsy. Along the fine optimization of a chemical series with a pharmacological target located in the CNS (target potency, brain penetration, and solubility), we successfully identified an Ames negative aminopyrazole as putative metabolite of this compound series. Our efforts culminated in the selection of compound 20, which was elected as a preclinical candidate.

Chemoprevention of respiratory-tract neoplasia in the hamster by oltipraz, alone and in combination

Two doses of oltipraz (300, 600 mg/kg diet) and alpha-difluoromethylornithine DFMO; 1600, 3200 mg/kg diet), alone and in combinations with N-(4-hydroxyphenyl) retinamide (4-HPR; 98, 196 mg/kg diet) and/or beta-carotene (3, 1.5 mg; sc, 2x/week), were investigated for prevention of hamster respiratory carcinogenesis. After 25 weeks, only high dose oltipraz (-100%) inhibited the incidence of DEN-induced (17.8 mg/kg BW, sc, 2x/week, 20 weeks) bronchial carcinomas when given alone. Low dose oltipraz (-34%, n.s.) synergistically decreased carcinoma incidence in combinations with 4-HPR (-80%), beta-carotene (-90%) or both (-100%). Other effective combinations were low dose DFMO + beta-carotene (-64%) and high dose DFMO with 4-HPR (-56%), beta-carotene (-63%) or both (-67%).

Omeprazole Absorption from a Compounded Transdermal Formulation in Healthy Volunteers

OBJECTIVE

To evaluate the plasma concentration versus time profile of omeprazole following the administration of a compounded transdermal gel formulation in healthy volunteers.

DESIGN

Single-dose transdermal pharmacokinetic (PK) study including a comparison with historical data from an oral PK study.

SETTING

Academic clinical research center.

PARTICIPANTS

Eight healthy volunteers between 18 and 50 years of age.

INTERVENTIONS

Omeprazole gel 40 mg (0.8 mL) was applied to the ventral surface of the forearm covering an area of 7 x 15 cm without an occlusive dressing. Blood samples were collected just before application and then at 1, 2, 3, 4, 6, and 8 hours. Plasma concentrations of omeprazole were determined using a validated liquid chromatography tandem mass spectrometry method.

MAIN OUTCOME MEASURES

PK parameters (maximal plasma concentration [C(max)], the time of C(max), [T(max)], the area under the omeprazole concentration versus time curve from 0 to 8 hours, the elimination rate constant, and the half-life of the elimination phase) following transdermal administration, compared with historical controls who had received an oral omeprazole 40 mg dose during a previous study.

RESULTS

Of the eight volunteers, five had undetectable plasma omeprazole concentrations throughout the 8-hour study, precluding a complete PK analysis. For the three volunteers with detectable plasma omeprazole concentrations, the values ranged from 0.204 to 0.552 ng/mL. Including values of 0 for the patients with undetectable levels, the mean (+/- SD) C(max) was 0.153 +/- 0.241 ng/mL, and the T(max) in patients with detectable levels occurred at approximately 6 hours. The plasma concentrations following transdermal administration were approximately 1,000-fold lower than those observed with oral dosing.

CONCLUSION

Transdermal absorption from a single dose of the omeprazole gel formulation used in this study was poor. This transdermal gel formulation is clearly not bioequivalent to the oral capsule.

Expression, crystallization and preliminary X-ray studies of the PDZ domain of Dishevelled protein

Dishevelled (Dsh) protein is an important component of the Wnt signal-transduction pathway. It has three relatively conserved domains: DIX, PDZ and DEP. The PDZ domain of the Xenopus laevis homolog of Dsh, which consists of residues 254-348, was overexpressed as a soluble protein in Escherichia coli, purified and crystallized. The crystals were obtained by the vapor-diffusion method, using 1.4 M sodium formate as a precipitant. The crystals diffracted to 2.3 A resolution. The space group was determined to be P6(1)22 or P6(5)22, with unit-cell dimensions a = b = 95.9, c = 93.9 A.

IgG reactivities against recombinant Rhoptry-Associated Protein-1 (rRAP-1) are associated with mixed Plasmodium infections and protection against disease in Tanzanian children

A cross-sectional sero-epidemiological study was performed in Magoda, Tanzania, an area where malaria is holoendemic. Blood samples were collected from children (1-4 years) and tested for IgG antibody reactivity against 2 recombinant protein fragments of Plasmodium falciparum Rhoptry-Associated Protein-1 (rRAP-1). The data were related to the prevalence of malarial disease and single P. falciparum or mixed Plasmodium infections. Fever (> or = 37.5 degrees C) in combination with parasite densities > 5000/microliter were used to distinguish between children with asymptomatic malaria infections and those with acute clinical disease. Furthermore, C-reactive protein (CRP) was applied as a surrogate marker of malaria morbidity. The prevalence of Plasmodium infections was 96.0%. Eleven children were defined as clinical malaria cases, all with single P. falciparum infections. The density of P. falciparum was significantly lower in children with mixed Plasmodium infections compared to those with single P. falciparum infections. Children with asymptomatic P. falciparum infections had higher IgG reactivities to rRAP-1, compared to IgG reactivities of children with malarial disease. Children with mixed Plasmodium infections generally showed elevated IgG reactivity to rRAP-1, when compared to children with single P. falciparum infections. The possible relationship between mixed species infections, clinical outcome of the disease and antibody responses to RAP-1 is discussed.

Stress response decreases the interleukin-1beta-induced production of complement component C3 in human intestinal epithelial cells

Interleukin-1beta (IL-1beta) increases the production of complement component C3 in enterocytes. Heat shock regulates the response to cytokines and other inflammatory mediators in various cell types. We tested the hypothesis that the heat-shock response regulates IL-1beta-induced C3 production in the enterocyte. Cultured Caco-2 cells, a human intestinal epithelial cell line, were treated with sodium arsenite (10-500 microM) for 1 h or subjected to hyperthermia (43 degrees C) for 1-4 h, and allowed to recover for 1 h. The cells were then treated with IL-1beta (0.5 ng/ml) for up to 24 h, whereafter C3 levels were measured by ELISA and C3 mRNA by Northern blot analysis. Heat-shock protein of 72 kDa (hsp72) was determined by Western blot analysis. Treatment of the cells with sodium arsenite or subjecting them to hyperthermia induced the expression of hsp72. The IL-1beta-induced expression of C3 mRNA and C3 production were down-regulated by hyperthermia and sodium arsenite in a dose-dependent fashion. The results suggest that the stress response induced by hyperthermia or sodium arsenite decreases IL-1beta-induced C3 production in human enterocytes.

Nuclear factor-kappaB is activated in intestinal mucosa during endotoxemia

BACKGROUND

The transcription factor nuclear factor-kappaB (NF-kappaB) regulates a large number of genes involved in the inflammatory response to critical illness. The intestinal mucosa plays an active role in the inflammatory and metabolic response to sepsis and endotoxemia, but it is not known if NF-kappaB is activated in the mucosa during these conditions.

OBJECTIVE

To test the hypothesis that endotoxemia in mice activates NF-kappaB in intestinal mucosa.

METHODS

Mice were injected subcutaneously with lipopolysaccharide, 12.5 mg/kg, or a corresponding volume of saline. At various intervals following injection, jejunal mucosa was harvested and nuclear and cytoplasmic fractions were prepared. The nuclear fractions were analyzed by electrophoretic mobility shift assay for NF-kappaB activation and by Western blot analysis for the NF-kappaB subunits p50 and p65. Cytoplasmic fractions were analyzed by Western blotting for the NF-kappaB inhibitory proteins IkappaB-alpha and IkappaB-beta.

RESULTS

Electrophoretic mobility shift assay showed that NF-kappaB was activated in jejunal mucosa 1 hour after injection of lipopolysaccharide and persisted for at least 4 hours. The NF-kappaB subunits p50 and p65 were present in nuclear fractions of mucosa from endotoxemic mice at the corresponding time points. Cytoplasmic levels of the inhibitory proteins IkappaB-alpha and IkappaB-beta decreased during endotoxemia, and the proteins were nearly absent 60 minutes after injection of lipopolysaccharide.

CONCLUSIONS

The results suggest that IkappaB is degraded and NF-kappaB is activated in intestinal mucosa during endotoxemia. The findings support the concept that the intestinal mucosa is an important component of the inflammatory response to sepsis and endotoxemia.

Complement C3 production in human intestinal epithelial cells is regulated by interleukin 1beta and tumor necrosis factor alpha

BACKGROUND

Sepsis and endotoxemia are associated with increased mucosal production of complement component C3; the enterocyte may be a source of C3 in these conditions.

OBJECTIVE

To test the hypothesis that interleukin 1beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha) regulate the production of C3 in the enterocyte at the transcriptional level and that this regulation is potentiated by interferon gamma (IFN-gamma).

METHODS

Cultured Caco-2 cells, a human intestinal epithelial cell line, were treated with various concentrations of human recombinant IL-1beta (0.005-1.25 ng/mL) or TNF-alpha (1-1000 U/mL) with or without the addition of IFN-gamma (250 U/mL). C3 levels in the culture medium were measured by enzyme-linked immunosorbent assay and cellular messenger RNA levels by Northern blot analysis.

RESULTS

Treatment of the Caco-2 cells with IL-1beta or TNF-alpha resulted in a time- and dose-dependent increase in C3 production. The use of IFN-gamma alone did not affect C3 production but potentiated the effect of IL-1beta and TNF-alpha in a synergistic manner. C3 messenger RNA levels were increased following stimulation with either cytokine.

CONCLUSIONS

C3 production in the enterocyte is regulated by IL-1beta and TNF-alpha at the transcriptional level, and this response is potentiated by IFN-gamma. The results suggest that C3 production in the intestinal mucosa may be regulated locally by cytokines in a paracrine or autocrine manner.

Influence of owner personality type on expression and treatment outcome of dominance aggression in dogs

OBJECTIVE

To determine the success rate of positive training methods and behavioral modification techniques in dogs with dominance aggression and to compare personality profiles between owners of dominant-aggressive and nondominant dogs.

DESIGN

Prospective clinical study.

ANIMALS

10 dominant-aggressive dogs and 10 non-dominant, nonaggressive control dogs.

PROCEDURE

Dominance aggression was quantified, using an aggression score, in the 10 dominant dogs before and after a nonconfrontational behavior modification program. The personality profile of the owners of dominant and control dogs, assessed by means of a Keirsey temperament sorter, was compared, as was the influence of owner personality on the outcome of behavioral modification in the dominant dogs.

RESULTS

9 of 10 dominant dogs responded to the nonconfrontational treatment program by a decrease in aggressive response to similar eliciting stimuli. Significant differences were not found between the personality of the owners of dominant versus control dogs, and owner personality did not significantly affect the outcome of behavior modification treatment.

CLINICAL IMPLICATIONS

Nonconfrontational behavior modification programs are effective in reducing owner-directed dominance aggression in dogs. Owner personality does not necessarily predispose certain individuals to assaults by dominant dogs or profoundly affect their ability to engage in a successful behavioral modification program.

Organic Electroluminescent Devices

Electroluminescence from organic materials has the potential to enable low-cost, full-color flat-panel displays, as well as other emissive products. Some materials have now demonstrated adequate efficiencies (1 to 15 lumens/watt) and lifetimes (>5000 hours) for practical use; however, the factors that govern lifetime remain poorly understood. This article provides a brief review of device principles and applications requirements and focuses on the understanding of reliability issues.

Combined third-generation implantable cardioverter defibrillator with permanent unipolar pacemakers: preliminary observations

As implantable cardioverter defibrillators (ICDs) are strictly contraindicated in the presence of unipolar pacemakers, currently available options in patients having such chronic pacing systems include: abandoning the implanted pacemaker and selecting an ICD with ventricular demand (VVI) pacing; or replacing the chronic (dual chamber) unipolar pacing system with a dedicated bipolar version prior to ICD implantation. In three patients with previously implanted unipolar pacemakers, we challenged the premise that all ICD systems are incompatible by combining with a third-generation transvenous ICD system (Medtronic 7217B PCD) incorporating true bipolar sensing, a self-limiting auto-adjusting sensitivity, and a tolerant VF detection algorithm. The potential for pacemaker-ICD interaction was minimized by separating the tip of the ICDs transvenous right ventricular pace/sense-defibrillation coil lead from that of the chronic pacemaker lead by > or = 2-3 cm, and by performing "worst case" intraoperative testing. Although ICD double-counting of the dual chamber pacemaker's atrial and ventricular pacing spikes could be provoked at extreme high output settings, it did not occur at clinically appropriate settings. More importantly, continuous high output asynchronous pacing during ventricular fibrillation (VF) did not interfere with ICD detection. During a mean follow-up period of 18 months, one patient has had VF appropriately terminated by the ICD. In the remaining two patients, proper VF detection and ICD function was reassessed at 3 months and/or at 1 year during noninvasive testing.

CONCLUSION

These preliminary findings demonstrate that this transvenous ICD system's VF sensing and detection features combined with careful implant technique, rigorous "worst case" testing for possible pacemaker-ICD interaction with regular follow-up, may permit implantation of this ICD system in patients with chronic unipolar pacing systems. Further studies are needed to validate the long-term clinical safety of this promising revised approach to a currently contraindicated device combination.

Settings as an important dimension in health education/promotion policy, programs, and research

Settings--community, worksite, schools, and healthcare sites--constitute an important dimension of health education/health promotion policy and programs and for research about program needs, feasibility, efficacy, and effectiveness. These settings vary in the extent of coverage of and relationships with their respective constituencies, valued outcomes, and quantity and quality of evidence about the effectiveness of setting-specific and cross-setting programs. Main sources of evidence for program efficacy and effectiveness are summarized, leading to the conclusion that strides have been made toward building a strong evidentiary base for health education/health promotion in these settings. Gaps in research exist, especially for diffusion of effective programs, new technologies, the influence of policy, relations between settings, and approaches to marginal and special subgroups. Recommendations are offered for cross-setting and within-setting research related to intervention.

Distribution of epidermal growth-factor receptors in normal and neoplastic mammary tissues

Epidermal growth factor (EGF) is considered to be mitogenic for proliferation of mammary glands in animals. The action of EGF is mediated by specific EGF receptors (EFG-R). In the present study, we investigated distribution of EGF receptors during various physiological stages of mammary glands, N-methyl-N-nitrosourea (MNU)-induced mammary tumors in rats and human breast cancer samples. EGF receptor concentrations were determined by Scatchard analyses in the membrane fraction of the tissues. Results showed increased EGF receptor levels in the structurally differentiated mammary tissues from pregnant rats; whereas lower concentrations were observed in the functionally differentiated glands from lactating rats. EGF receptors were absent in the majority of the tumors induced by MNU. The loss of EGF receptor was not observed during the first 20 days post carcinogen treatment, but appeared to be correlated with the onset of the tumor. Consistent with the literature, the majority of the steroid receptor positive human breast cancer samples were EGF receptor negative, whereas steroid receptor negative samples contained EGF receptors. These results suggest that the loss of EGF receptors in ovarian hormone dependent mammary tumors does not occur gradually during carcinogenesis but appears to be a characteristic of hormone dependent mammary tumor cells.

Flavonoids as DNA topoisomerase antagonists and poisons: structure-activity relationships

Selected flavonoids were tested for their ability to inhibit the catalytic activity of DNA topoisomerase (topo) I and II. Myricetin, quercetin, fisetin, and morin were found to inhibit both enzymes, while phloretin, kaempferol, and 4',6,7-trihydroxyisoflavone inhibited topo II without inhibiting topo I. Flavonoids demonstrating potent topo I and II inhibition required hydroxyl group substitution at the C-3, C-7, C-3', and C-4' positions and also required a keto group at C-4. Additional B-ring hydroxylation enhanced flavonoid topo I inhibitory action. A C-2, C-3 double bond was also required, but when the A ring is opened, the requirement for the double bond was eliminated. Genistein has been previously reported to stabilize the covalent topo II-DNA cleavage complex and thus function as a topo II poison. All flavonoids were tested for their ability to stabilize the cleavage complex between topo I or topo II and DNA. None of the agents stabilized the topo I-DNA cleavage complex, but prunetin, quercetin, kaempferol, and apigenin stabilized the topo II DNA-complex. Competition experiments have shown that genistein-induced topo II-mediated DNA cleavage can be inhibited by myricetin, suggesting that both types of inhibitors (antagonists and poisons) interact with the same functional domain of their target enzyme. These results are of use for the selection of flavonoids that can inhibit specific topoisomerases at specific stages of the topoisomerization reaction.

The dietary anticancer agent ellagic acid is a potent inhibitor of DNA topoisomerases in vitro

Ellagic acid and 12 related agents have been tested for their ability to inhibit the activities of human DNA topoisomerase (topo) I and II. Using specific in vitro assays, we found ellagic acid and flavellagic acid to be potent inhibitors of the catalytic activities of the two topoisomerases. The minimum concentration required to inhibit > or = 50% of catalytic activity (IC50) of ellagic acid was determined at 0.6 and 0.7 micrograms/ml for topo I and topo II, respectively. Flavellagic acid's IC50 was determined at 3.0 and 3.6 micrograms/ml for topo I and topo II, respectively. Unlike topoisomerase poisons, these two plant phenols did not trap the enzyme-DNA reaction intermediate, known as the cleavable complex. In contrast, ellagic acid prevented other topo I and topo II poisons from stabilizing the cleavable complex, suggesting that the mode of its action is that of an antagonist. Structure-activity studies identified the 3,3'-hydroxyl groups and the lactone groups as the most essential elements for the topoisomerase inhibitory actions of plant phenols. On the basis of these findings and other properties of ellagic acid, a mechanistic model for the documented anticarcinogenic effects of the agent is proposed.

Tumour necrosis factor and interleukin-6 production induced by components associated with merozoite proteins of Plasmodium falciparum

P. falciparum merozoite antigens, merozoite surface protein-1 (MSP-1) and rhoptry associated protein-1 (RAP-1), were shown to be liberated into the supernatant of in vitro parasite cultures and to be included in the endotoxin-like exoantigen complex, previously designated Ag7. Material affinity purified from culture supernatants, using immobilized monoclonal antibodies specific for RAP-1 or MSP-1, stimulated normal human mononuclear cells to produce TNF and IL-6 in vitro. However, stimulation of TNF was absent, and that of IL-6 was reduced, when the antigens were purified from detergent extracts of infected erythrocytes. These results indicate that the RAP-1 and MSP-1 proteins themselves do not stimulate the production of TNF. Instead, other components associating with these exoantigens may be responsible for the TNF production. Mouse antisera blocking TNF production stimulated by P. yoelii exoantigens also blocked TNF production stimulated by material affinity purified from P. falciparum culture supernatants using RAP-1 specific monoclonal antibody, indicating the conserved structure of the TNF inducing component.

Adjunctive hyperbaric oxygen for treatment of rhinocerebral mucormycosis

The therapy of rhinocerebral mucormycosis includes aggressive surgical debridement, administration of high-dose amphotericin B, and control of underlying predisposing conditions, especially diabetes and immunosuppression or immunodeficiency. Hyperbaric oxygen suppresses fungal growth in vitro and has theoretical value in treating mucormycosis because it reduces the tissue hypoxia and acidosis that accompany vascular invasion by the fungus. In a retrospective review of patients at Duke University Medical Center with rhinocerebral mucormycosis, six patients were treated with hyperbaric oxygen and seven cases (involving six patients) were treated without hyperbaric oxygen. All patients received surgical debridement and amphotericin B. Two of six patients receiving hyperbaric oxygen therapy died, and four of seven patients not receiving hyperbaric oxygen therapy died. Adverse effects from hyperbaric oxygen were minimal. Because mucormycosis occurs infrequently, this retrospective review involved a small number of patients. Despite this limitation, adjunctive hyperbaric oxygen appears to be a promising clinical modality for the treatment of rhinocerebral mucormycosis and warrants further investigation.

Enalapril maleate and atenolol combined with hydrochlorothiazide in moderate to severe essential hypertension

This open randomised parallel trial compared the antihypertensive efficacy of enalapril and atenolol given alone once a day or with hydrochlorothiazide in 20 patients with moderate to severe hypertension. Active treatment was over a 26 week period, consisting of an initial titration phase followed by a fixed dose phase. Both treatment regimes effectively lowered systolic and diastolic blood pressures. All patients on enalapril reached normotension (supine diastolic blood pressure less than or equal to 90 mmHg) compared with 78% on atenolol. Pulse rate was not appreciably changed by enalapril, but was significantly reduced by atenolol. No serious adverse reactions or significant changes in laboratory values were noted in either group. The commonest adverse reaction with enalapril was dizziness which occurred in two cases and resolved on dosage reduction. Enalapril with hydrochlorothiazide given once daily may provide a useful combination in the treatment of moderate to severe hypertension.