The use of basiliximab-infliximab combination for the treatment of severe gastrointestinal acute GvHD

After allogeneic stem cell transplant, severe grade III-IV gastrointestinal (GI) acute GvHD is associated with significant morbidity and mortality, and generally results in poor outcomes. Salvage therapy for patients who fail steroid therapy is not well defined in the literature. In the current retrospective study, we reviewed our experience with the combination of basiliximab and infliximab in 21 patients with severe, grade III-IV GI acute GvHD of whom 16 met the definition for steroid-refractory disease. The overall response rate was 76%, with 43% CR at a median time of 21 days after beginning treatment. The survival at 1 year was 24%, with most deaths due to complications from GvHD and recurrence of primary disease. All five of the long-term survivors have chronic GvHD. On the basis of a review of the literature, this regimen does not seem to be significantly more effective than other strategies for severe GI GvHD and seems to be worse than the results reported for basiliximab alone. Future studies of single-agent basiliximab and newer agents are required.

Formulation and in vitro evaluation of niacin-loaded nanoparticles to reduce prostaglandin mediated vasodilatory flushing

OBJECTIVE

Niacin, activating G-protein coupled receptor (GPR) 109A, stimulates release of vasodilatory prostaglandins (PGs) such as PGE2 which can elicit niacin-associated flushing side effects. Poly-lactic-co-glycolic acid (PLGA) and poly-lactic acid (PLA) are used in nanoparticle (NP) drug delivery to reduce adverse effects and modulate drug release. Our study evaluated the in vitro effects of niacin-loaded PLGA or PLA-NPs on PGE2 expression in whole human blood as a model for niacin-induced flushing.

MATERIALS AND METHODS

NPs were formulated using a solvent evaporation process and characterized by size, polydispersity, zeta potential, drug entrapment, morphology, and drug release. NP in vitro effects on PGE2 release were measured via ELISA analysis.

RESULTS

PLGA-NPs demonstrated the lowest NP size (66.7 ± 0.21 nm) with the highest zeta potential and percent drug entrapment (42.00 ± 1.62 mV and 69.09 ± 0.29%, respectively) when compared to PLA-NPs (130.4 ± 0.66 nm, 27.96 ± 0.18 mV, 69.63 ± 0.03 %, respectively). In vitro release studies showed that PLGA-NPs underwent significant reductions in cumulative drug release when compared to PLA-NPs (p < 0.05). Furthermore, when compared to plain niacin, PLGA-NPs significantly reduced in vitro PGE2 release (p < 0.05).

CONCLUSIONS

These results support the use of PLGA-NPs as a novel method of delivery for reducing niacin-associated flushing.

Effects of formulation design on niacin therapeutics: mechanism of action, metabolism, and drug delivery

Niacin is a highly effective, lipid regulating drug associated with a number of metabolically induced side effects such as prostaglandin (PG) mediated flushing and hepatic toxicity. In an attempt to reduce the development of these adverse effects, scientists have investigated differing methods of niacin delivery designed to control drug release and alter metabolism. However, despite successful formulation of various orally based capsule and tablet delivery systems, patient adherence to niacin therapy is still compromised by adverse events such as PG-induced flushing. While the primary advantage of orally dosed formulations is ease of use, alternative delivery options such as transdermal delivery or polymeric micro/nanoparticle encapsulation for oral administration have shown promise in niacin reformulation. However, the effectiveness of these alternative delivery options in reducing inimical effects of niacin and maintaining drug efficacy is still largely unknown and requires more in-depth investigation. In this paper, we present an overview of niacin applications, its metabolic pathways, and current drug delivery formulations. Focus is placed on oral immediate, sustained, and extended release niacin delivery as well as combined statin and/or prostaglandin antagonist niacin formulation. We also examine and discuss current findings involving transdermal niacin formulations and polymeric micro/nanoparticle encapsulated niacin delivery.

Effect of formulation variables on preparation of celecoxib loaded polylactide-co-glycolide nanoparticles

Polymer based nanoparticle formulations have been shown to increase drug bioavailability and/or reduce drug adverse effects. Nonsteroidal anti-inflammatory drugs (e.g. celecoxib) reduce prostaglandin synthesis and cause side effects such as gastrointestinal and renal complications. The aim of this study was to formulate celecoxib entrapped poly lactide-co-glycolide based nanoparticles through a solvent evaporation process using didodecyldimethylammonium bromide or poly vinyl alcohol as stabilizer. Nanoparticles were characterized for zeta potential, particle size, entrapment efficiency, and morphology. Effects of stabilizer concentration (0.1, 0.25, 0.5, and 1% w/v), drug amount (5, 10, 15, and 20 mg), and emulsifier (lecithin) on nanoparticle characterization were examined for formula optimization. The use of 0.1, 0.25, and 0.5% w/v didodecyldimethylammonium bromide resulted in a more than 5-fold increase in zeta potential and a more than 1.5-fold increase in entrapment efficiency with a reduction in particle size over 35%, when compared to stabilizer free formulation. Nanoparticle formulations were also highly influenced by emulsifier and drug amount. Using 0.25% w/v didodecyldimethylammonium bromide NP formulations, peak zeta potential was achieved using 15 mg celecoxib with emulsifier (17.15±0.36 mV) and 20 mg celecoxib without emulsifier (25.00±0.18 mV). Peak NP size reduction and entrapment efficiency was achieved using 5 mg celecoxib formulations with (70.87±1.24 nm and 95.55±0.66%, respectively) and without (92.97±0.51 nm and 95.93±0.27%, respectively) emulsifier. In conclusion, formulations using 5 mg celecoxib with 0.25% w/v didodecyldimethylammonium bromide concentrations produced nanoparticles exhibiting enhanced size reduction and entrapment efficiency. Furthermore, emulsifier free formulations demonstrated improved zeta potential when compared to formulations containing emulsifier (p<0.01). Therefore, our results suggest the use of emulsifier free 5 mg celecoxib drug formulations containing 0.25% w/v didodecyldimethylammonium bromide for production of polymeric NPs that demonstrate enhanced zeta potential, small particle size, and high entrapment efficiency.

Haemophilia Experiences, Results and Opportunities (HERO) study: treatment-related characteristics of the population

The HERO (Haemophilia Experiences, Results and Opportunities) quantitative surveys collected information on characteristics and perceptions of adult persons with haemophilia (PWH) and parents of children with haemophilia. The aim of this article is to describe the perceptions of PWH and parents on psychosocial aspects related to treatment. Two online surveys (one for PWH, one for parents) were conducted in 10 countries. Among 675 PWH respondents, 77% reported having responsibility for their own care; 72% of 561 parent respondents had the main responsibility for their son. PWH were most commonly treated on demand (45% of 648 adults using factor concentrate), with 32% on regular prophylaxis and 23% treated on demand with short-term prophylaxis (e.g. for sports/physiotherapy). Children were most often treated with prophylaxis (65% of 549 children using factor concentrate), with 26% treated on demand and 8% treated on demand with short-term prophylaxis. Factor was generally used as instructed at home. Some respondents (41% PWH; 30% parents) had difficulties/concerns with factor availability/affordability. PWH reported more bleeds in the last 12 months than parents reporting their son's bleeds (mean 17.8 vs. 8.7). Both PWH and parents generally perceived that overall, their (their son's) haemophilia was well controlled. Results differed by country. The HERO study captured new, patient-based data regarding many facets of life relevant to PWH, including treatment. The information conveyed in this article largely represents new insights regarding perceptions of treatment and provides initial benchmark statistics for further research.

Nanoparticles in drug delivery: mechanism of action, formulation and clinical application towards reduction in drug-associated nephrotoxicity

INTRODUCTION

Over the past few decades, nanoparticles (NPs) have gained immeasurable interest in the field of drug delivery. Various NP formulations have been disseminated in drug development in an attempt to increase efficacy, safety and tolerability of incorporated drugs. In this context, NP formulations that increase solubility, control release, and/or affect the in vivo disposition of drugs, were developed to improve the pharmacokinetic and pharmacodynamic properties of encapsulated drugs.

AREAS COVERED

In this article, important properties related to NP function such as particle size, surface charge and shape are disseminated. Also, the current understanding of how NP characteristics affect particle uptake and targeted delivery is elucidated. Selected NP systems currently used in delivery of drugs in biological systems and their production methods are discussed as well. Emphasis is placed on current NP formulations that are shown to reduce drug-induced adverse renal complications.

EXPERT OPINION

Formulation designs utilizing NP-encapsulated drugs offer alternative pharmacotherapy options with improved safety profiles for current and emerging drugs. NPs have been shown to increase the therapeutic index of several entrapped drugs mostly by decreasing drug localization and side effects on organs. Recent studies on NP-encapsulated chemotherapeutic and antibiotic medications show enhanced therapeutic outcomes by altering drug degradation, increasing systemic circulation and/or enhancing cell specific targeting. They may also reduce the distribution of encapsulated drugs into the kidneys and attenuate drug-associated adverse renal complications. The usefulness of NP formulation in reducing the nephrotoxicity of nonsteroidal anti-inflammatory drugs is an under explored territory that deserves more attention.

Haemophilia Experiences, Results and Opportunities (HERO) Study: influence of haemophilia on interpersonal relationships as reported by adults with haemophilia and parents of children with haemophilia

Evidence delineating the effects of haemophilia on interpersonal relationships is sparse and largely outdated, failing to reflect the impact of current treatment strategies. HERO (Haemophilia Experiences, Results and Opportunities) was commenced to garner a more comprehensive understanding of psychosocial issues facing persons with haemophilia (PWH). This article describes the findings of the quantitative HERO survey relating to the influence of haemophilia on interpersonal relationships of adult PWH, and parents/caregivers of children with haemophilia. Separate questionnaires were completed by adult PWH and parents of minor children from 10 countries, including satisfaction with support from partners, family, friends and other social contacts; disclosure of haemophilia and carrier status and family dynamics. A total of 675 PWH and 561 parents completed the survey. Over half of PWH (57%) and parents (84%) were married. Most PWH were satisfied with support from partners (94%), family (90%) and friends (85%), with lower percentages reported among those with inhibitors. Most parents were likewise satisfied with support from partners (88%) and family (83%). Whereas PWH were reticent to disclose their diagnosis beyond family and friends, parents were more likely to share their son's diagnosis, and most were satisfied with the support from their son's peers (74%), teachers (83%) and other adults in supervisory roles (85%). PWH and parents surveyed were satisfied overall with the support they received from partners, family, friends and social contacts. Relationships are affected by haemophilia in various ways, and particularly affected in terms of disease burden, age and social life.

Exacerbation of celecoxib-induced renal injury by concomitant administration of misoprostol in rats

Nonsteroidal anti-inflammatory drugs (NSAIDs) can produce adverse effects by inhibiting prostaglandin (PG) synthesis. A PGE1 analogue, misoprostol, is often utilized to alleviate NSAID-related gastrointestinal side effects. This study examined the effect of misoprostol on celecoxib renal toxicity. Additionally, the effects of these drugs on cardiovascular parameters were evaluated. Four randomized rat groups were orally gavaged for 9 days, two groups receiving vehicle and two groups receiving misoprostol (100 µg/kg) twice daily. Celecoxib (40 mg/kg) was co-administered once daily to one vehicle and one misoprostol group from days 3 to 9. Urine and blood samples were collected and blood pressure parameters were measured during the study period. Hearts and kidneys were harvested on final day. Day 2 urinary electrolyte samples revealed significant reductions in sodium excretion in misoprostol (0.12 ± 0.05 µmol/min/100 g) and misoprostol+celecoxib groups (0.07 ± 0.02 µmol/min/100 g). At day 3, all treatment groups showed significantly reduced sodium excretion. Potassium excretion diminished significantly in vehicle+celecoxib and misoprostol+celecoxib groups from day 3 onward. Urinary kidney injury molecule-1 levels were significantly increased in vehicle+celecoxib (0.65 ± 0.02 vs. 0.35 ± 0.07 ng/mL, p = 0.0002) and misoprostol+celecoxib (0.61 ± 0.06 vs. 0.37 ± 0.06 ng/mL, p = 0.0015) groups when compared to baseline; while plasma levels of cardiac troponin I increased significantly in vehicle+celecoxib (p = 0.0040) and misoprostol+misoprostol (p = 0.0078) groups when compared to vehicle+vehicle. Blood pressure parameters increased significantly in all misoprostol treated groups. Significant elevation in diastolic (p = 0.0071) and mean blood pressure (p = 0.0153) was noted in misoprostol+celecoxib compared to vehicle+celecoxib. All treatments produced significant tubular dilatation/necrosis compared to control. No significant myocardial changes were noticed; however, three animals presented with pericarditis. Kidney, heart, and plasma celecoxib levels revealed no significant change between vehicle+celecoxib and misoprostol+celecoxib. Concomitant misoprostol administration did not prevent celecoxib renal toxicity, and instead exacerbated renal side effects. Misoprostol did not alter plasma or tissue celecoxib concentrations suggesting no pharmacokinetic interaction between celecoxib and misoprostol.

Design and optimization of PLGA-based diclofenac loaded nanoparticles

Drug based nanoparticle (NP) formulations have gained considerable attention over the past decade for their use in various drug formulations. NPs have been shown to increase bioavailability, decrease side effects of highly toxic drugs, and prolong drug release. Nonsteroidal anti-inflammatory drugs such as diclofenac block cyclooxygenase expression and reduce prostaglandin synthesis, which can lead to several side effects such as gastrointestinal bleeding and renal insufficiency. The aim of this study was to formulate and characterize diclofenac entrapped poly(lactide-co-glycolide) (PLGA) based nanoparticles. Nanoparticles were formulated using an emulsion-diffusion-evaporation technique with varying concentrations of poly vinyl alcohol (PVA) (0.1, 0.25, 0.5, or 1%) or didodecyldimethylammonium bromide (DMAB) (0.1, 0.25, 0.5, 0.75, or 1%) stabilizers centrifuged at 8,800 rpm or 12,000 rpm. The resultant nanoparticles were evaluated based on particle size, zeta potential, and entrapment efficacy. DMAB formulated NPs showed the lowest particle size (108±2.1 nm) and highest zeta potential (−27.71±0.6 mV) at 0.1 and 0.25% respectively, after centrifugation at 12,000 rpm. Results of the PVA based NP formulation showed the smallest particle size (92.4±7.6 nm) and highest zeta potential (−11.14±0.5 mV) at 0.25% and 1% w/v, respectively, after centrifugation at 12,000 rpm. Drug entrapment reached 77.3±3.5% and 80.2±1.2% efficiency with DMAB and PVA formulations, respectively. The results of our study indicate the use of DMAB for increased nanoparticle stability during formulation. Our study supports the effective utilization of PLGA based nanoparticle formulation for diclofenac.

A simple high performance liquid chromatography method for determination of rebamipide in rat urine

Rebamipide is a mucoprotective agent commonly used to prevent nonsteriodal anti-inflammatory drug-induced gastrointenstinal side effects [1]. Human plasma and urine analysis of rebamipide utilizing high performance liquid chromatography (HPLC) have been reported [2]. Recently, we reported on the plasma levels of rebamipide in presense or absence of celecoxib or diclofenac in rats [3] using a modified HPLC method of detection developed by Jeoung et al. [4]. To tailor the method towards use in urinary rebamipide extraction and analysis, the following modifications were made:•

To compensate for high concentrations of rebamipide found in urine, a new rebamipide stock solution was prepared with a final concentration of 50,000 ng/mL.

•

Rat urine calibration standards were obtained within the range of 50–1000 ng/mL and 1000–50,000 ng/mL.

•

Plasma samples were replaced with urine samples.

Pharmacokinetic interactions between rebamipide and selected nonsteroidal anti-inflammatory drugs in rats

Nonsteroidal anti-inflammatory drugs (NSAIDs) cause gastrointestinal and renal side effects. Rebamipide is a mucoprotective agent that reduces gastrointenstinal side effects when administered concomitantly with NSAIDs. In this study, we investigated the pharmacokinetic drug interactions of rebamipide with two selected NSAIDs, celecoxib or diclofenac. Rats were randomly divided into five groups. Two groups received placebo and three groups were administered rebamipide (30 mg/kg) orally twice daily for two days. On day 3, the animals treated with placebo received celecoxib (40 mg/kg) or diclofenac (10mg/kg) and rats receiving rebamipide were administerd rebamipide followed by a single dose of placebo, celecoxib, or diclofenac. To investigate drug protein interactions, blank rat plasma was spiked with known concentrations of rebamipide, diclofenac plus rebamipide, or celecoxib plus rebamipide then dialyzed through a Rapid Equilibrium Dialysis device. AUC (139.70±24.97 μg h/mL), Cmax (42.99±2.98 μg/mL), and CLoral (0.08±0.02 L/h/kg) values of diclofenac in diclofenac plus rebamipide group altered when compared to those of diclofenac treated groups. Treatment with rebamipide showed no significant change in pharmacokinetic parameters of celecoxib treated rats. Cmax (7.80±1.22 μg/mL), AUC (56.46±7.30 μg h/mL), Vd/F (7.55±1.37 L/kg), and CLoral (0.58±0.09 L/h/kg) of rebamipide were significantly altered when diclofenac was co-administered with rebamipide. Pharmacokinetic parameters of rebamipide plus celecoxib group were not significantly different from those of rebamipide group. Plasma protein binding was not affected by concomitant administration of another drug. These results indicate alteration of pharmacokinetic parameters of both rebamipide and diclofenac when co-administered and cannot be explained by a variation in plasma protein binding.

A community and school approach to drug prevention and early intervention with high risk elementary school children

This study examines the effectiveness of a primary drug prevention/early intervention counseling program for elementary school children. The program, sponsored by a community drug treatment and prevention agency, assists children in acquiring social skills, reducing behavioral problems, and increasing academic success. The program is currently implemented in targeted public schools in Northeast Florida. It is a model which demonstrates the effectiveness of a community and school alliance in positively impacting social skills and behavioral correlates leading to adolescent drug experimentation. Results of the study indicate that the counseling program significantly impacted behavioral problems such as Acting Out, Immaturity, and Distractibility as measured by the Walker Problem Behavior Checklist. Some improvements were also noted in the children's self-concept, particularly in perceptions of peer acceptance, as measured by the Piers-Harris Self-Concept Scale.

Differential effects of infliximab on absolute circulating blood leucocyte counts of innate immune cells in early and late rheumatoid arthritis patients

Anti-tumour necrosis factor (TNF) biologics have revolutionized therapy of rheumatoid arthritis (RA). We compared the effects of infliximab on numbers of circulating leucocyte subsets in early RA (disease/symptom duration of ≤1 year) and late RA patients (>1 year). A control group consisted of early RA patients treated with a combination of methotrexate (MTX) and methylprednisolone. Blood samples were obtained at baseline (pre-therapy) from all RA patients, divided into three groups: (i) late RA receiving infliximab/MTX, (ii) early RA-infliximab/MTX, (iii) early RA-steroid/MTX, and also from follow-up patients at 2 and 14 weeks. Significant differences in absolute counts of monocytes and granulocytes were observed between healthy controls and RA patients. At baseline CD14(bright) monocytes and CD16(+) granulocytes were increased in both early RA and late RA patients. CD4(+) T cells, CD8(+) T cells and B cells were all increased at baseline in early RA, but not in late RA. At 2 weeks following infliximab treatment decreased granulocytes were observed in both early and late RA and decreased natural killer (NK) cells in late RA. CD16(+) granulocytes and NK cells were also decreased at 14 weeks post-infliximab in early RA. Biotinylated infliximab was used to detect membrane-associated TNF (mTNF)-expressing leucocytes in RA patients. CD16(+) granulocytes, NK cells and CD14(dim) monocytes all expressed higher levels of mTNF in RA patients. In summary infliximab is associated with decreased CD16(+) granulocyte and NK cell counts, possibly through binding of mTNF. Differential effects of infliximab between early and late RA suggest that pathogenic mechanisms change as disease progresses.

Health-related quality of life in haemophilia patients with inhibitors and their caregivers

Data on the health-related quality of life (HRQoL) of congenital haemophilia patients with inhibitors (CHwI) and their caregivers are limited. To understand the association between patient demo-graphics/clinical characteristics with HRQoL among CHwI patients and caregivers, a survey was developed to assess HRQoL with haemophilia-specific QoL questionnaires (HAEMO-QoL/HAEM-A-QoL). In the cross-sectional study, paper-pencil questionnaires were mailed to 261 US CHwI patients/caregivers in July 2010. Descriptive analyses were performed to characterize HRQoL by age and to identify drivers of impairment, from both patient/caregiver perspectives. HRQoL scores were transformed on a scale of 0-100, with higher scores indicating higher impairment in HRQoL. Ninety-seven respondents completed the HRQoL assessment. HRQoL impairment was higher in adult patients. In children ages 8-16 years, mean HAEMO-QoL total score was 33.8 (SD = 15.5), and 35.0 (SD = 16.1) in children ages 4-7 years; for adult patients the mean HAEM-A-QoL total score was 42.2 (SD = 14.8). Adults reported highest impairment in the 'sports/leisure' subscale (Mean = 62.5, SD = 18.7), whereas patients 8-16 years reported highest impairment in the 'physical health' subscale (Mean = 50.8, SD = 30.5).Caregivers of patients ages 4-7 years reported greatest impairment within the 'family' subscale (Mean = 55.6, SD = 19.4). Caregivers were ''considerably/very much'' bothered by their child's inhibitors and reported higher QoL impairment for their child than parents who were not bothered. Within ChwI patients, HRQoL impairments increased with age and existed across a range of physical/psychosocial domains. In addition, caregiver burden also affected the perceived HRQoL of paediatric CHwI patients. Additional research is considered necessary to further understand the support caregivers need while caring for children with CHwI.

Patient/caregiver-reported recombinant factor VIIa (rFVIIa) dosing: home treatment of acute bleeds in the Dosing Observational Study in Hemophilia (DOSE)

Patients with congenital haemophilia with inhibitors experience acute bleeds managed with bypassing agents, such as recombinant FVIIa (rFVIIa). Home-based treatment and dosing patterns in the US remain poorly described. This study aimed to assess the prescribed and actual rFVIIa dosing in frequently bleeding inhibitor patients (≥4 bleeds in 3 months) prescribed first-line therapy with rFVIIa. Patients or caregivers recorded daily diaries, including the details of all bypassing agent infusions for 3-6 months. Median (range) initial rFVIIa dose prescribed for joint, muscle and other bleeds was 167.5 (61.0-289.0) mcg kg(-1). Additional rFVIIa doses prescribed were 90 (61-270) mcg kg(-1) at an interval of 2.5-3 (1-24) h. The actual initial rFVIIa dose reported by patients/caregivers for 158 bleeds was 212 (59-400) mcg kg(-1), with total dose per episode of 695 (74-21257) mcg kg(-1). Patient/caregiver-reported average dose per bleed was 146 (40-400) mcg kg(-1) across 5 (1-106) infusions. The initial rFVIIa dose was higher for haemarthrosis (223 [59-400] mcg kg(-1)) than muscle bleeds (148 [74-300] mcg kg(-1); P = 0.07). Initial and mean dose per day changed as treatment progressed. The DOSE study indicates that frequently bleeding inhibitor patients are prescribed and use higher rFVIIa dosing for all bleed types than recommended in the package insert (90 mcg kg(-1)). The rFVIIa dosing was highly variable within and across bleed types, with higher initial doses used for joint bleeds than muscle and other bleed types, particularly in the first days of treatment. This suggests that patients/caregivers have adopted home treatment strategies based on physician discretion and individual responses and experience.

Prognostic significance of CD44 expression in adenocarcinoma of the lung

Aims-To determine whether expression of CD44 in neoplasia is associated with tumour grade, stage and prognosis.Methods-The immunohistochemical expression of CD44 was evaluated using the mouse antihuman monoclonal antibody 3G12 which recognises regions shared by all CD44 isoforms to determine whether expression in formalin fixed, paraffin wax embedded tissue correlates with tumour grade, stage or survival in adenocarcinoma of the lung. Thirty one adenocarcinomas of the lung, 16 T2N0 and 15 T2N1, and their nodal metastases were studied.Results-Of the 31 tumours, 25 were positive for the CD44 antigen. CD44 expression correlated with tumour grade, in that intense staining was seen only in moderately and/or poorly differentiated tumours. CD44 did not correlate with nodal status, tumour size, pleural invasion, angiolymphatic invasion, or host inflammatory response, but did correlate with survival. A median survival of 46 months was observed in patients with moderate to strong CD44 expression compared with 24 months for those with no or weak expression. Nine patients were alive without evidence of disease at a median follow up of 61 months. Six (66%) of these nine patients had strong CD44 expression. This contrasts with strong expression in only three (17%) of the 17 patients dying with a median survival of 28 months.Conclusion-In primary adenocarcinoma of the lung loss of CD44 expression is associated with less favorable outcome and may indicate a more aggressive neoplasm. CD44 may be a useful prognostic marker in lung carcinoma.

Can syndromic thresholds provide early warning of national influenza outbreaks?

BACKGROUND

Influenza incidence thresholds are used to help predict the likely impact of influenza and inform health professionals and the public of current activity. We evaluate the potential of syndromic data (calls to a UK health helpline NHS Direct) to provide early warning of national influenza outbreaks.

METHODS

Time series of NHS Direct calls concerning 'cold/flu' and fever syndromes for England and Wales were compared against influenza-like-illness clinical incidence data and laboratory reports of influenza. Poisson regression models were used to derive NHS Direct thresholds. The early warning potential of thresholds was evaluated retrospectively for 2002-06 and prospectively for winter 2006-07.

RESULTS

NHS Direct 'cold/flu' and fever calls generally rose and peaked at the same time as clinical and laboratory influenza data. We derived a national 'cold/flu' threshold of 1.2% of total calls and a fever (5-14 years) threshold of 9%. An initial lower fever threshold of 7.7% was discarded as it produced false alarms. Thresholds provided 2 weeks advanced warning of seasonal influenza activity during three of the four winters studied retrospectively, and 6 days advance warning during prospective evaluation.

CONCLUSION

Syndromic thresholds based on NHS Direct data provide advance warning of influenza circulating in the community. We recommend that age-group specific thresholds be developed for other clinical influenza surveillance systems in the UK and elsewhere.

Linking syndromic surveillance with virological self-sampling

Calls to a UK national telephone health helpline (NHS Direct) have been used for syndromic surveillance, aiming to provide early warning of rises in community morbidity. We investigated whether self-sampling by NHS Direct callers could provide viable samples for influenza culture. We recruited 294 NHS Direct callers and sent them self-sampling kits. Callers were asked to take a swab from each nostril and post them to the laboratory. Forty-two per cent of the samples were returned, 16.2% were positive on PCR for influenza (16 influenza A(H3N2), three influenza A (H1N1), four influenza B) and eight for RSV (5.6%). The mean time between the NHS Direct call and laboratory analysis was 7.4 days. These samples provided amongst the earliest influenza reports of the season, detected multiple influenza strains, and augmented a national syndromic surveillance system. Self-sampling is a feasible method of enhancing community-based surveillance programmes for detection of influenza.

A national syndromic surveillance system for England and Wales using calls to a telephone helpline

Routine primary care data provide the means to monitor a variety of syndromes which could give early warning of health protection issues. In the United Kingdom, a national syndromic surveillance system, operated jointly by the UK Health Protection Agency (HPA) and NHS Direct (a national telephone health helpline), examines symptoms reported to NHS Direct. The aim of the system is to identify an increase in syndromes indicative of common infections and diseases, or the early stages of illness caused by the deliberate release of a biological or chemical agent. Data relating to 11 key symptoms/syndromes are received electronically from all 22 NHS Direct call centres covering England and Wales and analysed by the HPA on a daily basis. Statistically significant excesses in calls are automatically highlighted and assessed by a multi-disciplinary team. Although the surveillance system has characterised many sudden rises in syndromes reported to NHS Direct, no evidence of a biological or chemical attack has been detected. Benefits of this work, however, are early warning and tracking of rises in community morbidity (e.g. influenza-like illness, heatstroke); providing reassurance during times of perceived high risk (e.g. after the 7 July 2005 London bombs and December 2005 Buncefield oil depot fire); and timely surveillance data for influenza pandemic planning and epidemic modeling.

Can syndromic surveillance data detect local outbreaks of communicable disease? A model using a historical cryptosporidiosis outbreak

A national UK surveillance system currently uses data from a health helpline (NHS Direct) in an attempt to provide early warning of a bio-terrorist attack, or an outbreak caused by a more common infection. To test this syndromic surveillance system we superimposed data from a historical outbreak of cryptosporidiosis onto a statistical model of NHS Direct call data. We modelled whether calls about diarrhoea (a proxy for cryptosporidiosis) exceeded a statistical threshold, thus alerting the surveillance team to the outbreak. On the date that the public health team were first notified of the outbreak our model predicted a 4% chance of detection when we assumed that one-twentieth of cryptosporidiosis cases telephoned the helpline. This rose to a 72% chance when we assumed nine-tenths of cases telephoned. The NHS Direct surveillance system is currently unlikely to detect an event similar to the cryptosporidiosis outbreak used here and may be most suited to detecting more widespread rises in syndromes in the community, as previously demonstrated. However, the expected rise in NHS Direct call rates, should improve early warning of outbreaks using call data.

A national syndromic surveillance system for England and Wales using calls to a telephone helpline

Routine primary care data provide the means to monitor a variety of syndromes which could give early warning of health protection issues. In the United Kingdom, a national syndromic surveillance system, operated jointly by the UK Health Protection Agency (HPA) and NHS Direct (a national telephone health helpline), examines symptoms reported to NHS Direct. The aim of the system is to identify an increase in syndromes indicative of common infections and diseases, or the early stages of illness caused by the deliberate release of a biological or chemical agent. Data relating to 11 key symptoms/syndromes are received electronically from all 22 NHS Direct call centres covering England and Wales and analysed by the HPA on a daily basis. Statistically significant excesses in calls are automatically highlighted and assessed by a multi-disciplinary team. Although the surveillance system has characterised many sudden rises in syndromes reported to NHS Direct, no evidence of a biological or chemical attack has been detected. Benefits of this work, however, are early warning and tracking of rises in community morbidity (e.g. influenza-like illness, heatstroke); providing reassurance during times of perceived high risk (e.g. after the 7 July 2005 London bombs and December 2005 Buncefield oil depot fire); and timely surveillance data for influenza pandemic planning and epidemic modeling.

Target isotope effects for vibrationally-resolved electron capture in low-energy collisions of O3+ with molecular hydrogen

Using a quantum-mechanical molecular-orbital coupled-channel (QMOCC) approach, we investigate single electron capture in collisions of O3+ with various molecular hydrogen isotopomers (H2, HD, T2) for collision energies of 1 and 100 eV u(-1). Potential energy surfaces and nonadiabatic couplings obtained with the spin-coupled valence-bond method are incorporated into QMOCC calculations of vibrationally-resolved cross sections of the product molecular ion. The infinite order sudden approximation is adopted and comparisons of the vibrational distributions are made with the centroid approximation, which incorporates ionization Franck-Condon factors. Intercomparison of the results is used to assess the reliability of the approximations and to give insight into the target isotope effects.

Cisplatin, fluorouracil, and leucovorin induction chemotherapy followed by concurrent cisplatin chemoradiotherapy for organ preservation and cure in patients with advanced head and neck cancer: long-term follow-up

PURPOSE

The poor functional outcome in patients with advanced head and neck squamous cell carcinoma (HNSCC) with surgery and radiation has led to alternative approaches to advanced disease. We conducted a phase II study of induction chemotherapy followed by concurrent chemoradiotherapy for organ preservation in patients with advanced resectable and unresectable (nasopharyngeal) tumors.

PATIENTS AND METHODS

Forty-two patients with stage III to IV resectable HNSCC and nasopharyngeal tumors received induction chemotherapy with two courses of cisplatin (20 mg/m2/d continuous infusion [CI]), fluorouracil (800 mg/m2/d CI), and leucovorin (500 mg/m2/d CI; PFL) for 4 days followed by concurrent therapy with cisplatin (100 mg/m2/d on days 1 and 22) and approximately 70 Gy of external-beam radiotherapy.

RESULTS

Response to induction chemotherapy included partial response rate of 52% and complete response rate of 24%. The most common grade 3 or 4 toxicity was neutropenia (59%). After cisplatin chemoradiotherapy the complete response rate was 67%. Toxicities of cisplatin chemoradiotherapy consisted of grade 3 or 4 mucositis (79%) and neutropenia (51%). At a median follow-up of 71.5 months, 43% of the patients are still alive and disease-free. The 5-year progression-free survival (PFS) rate was 60%, and the 2- and 5-year overall survival (OS) rates were 67% and 52%, respectively. Three patients died of second primaries. Late complications of treatment included xerostomia and hoarseness. One patient had persistent dysphagia and required laser epiglotectomy 108 months after treatment.

CONCLUSION

Induction chemotherapy with PFL followed by concurrent cisplatin chemoradiotherapy is well tolerated and results in a good likelihood of organ preservation and excellent PFS and OS.

A simplified approach to stem cell mobilization in multiple myeloma patients not previously treated with alkylating agents

High-dose chemotherapy and autologous stem cell rescue is considered a standard part of initial therapy for patients with multiple myeloma. Therefore, potential transplant candidates are generally treated with dexamethasone-based programs rather than alkylating agents to avoid stem cell toxicity. The optimal mobilizing regimen for patients with multiple myeloma has not been defined. However, aggressive chemotherapy may result in excessive morbidity and cost in this older, immunocompromised population. We retrospectively examined our experience with a well-tolerated regimen of 1.5 g/m(2) cyclophosphamide on day -10 followed by 10 microg/kg G-CSF beginning on day -7 in 50 consecutive patients with multiple myeloma and no prior alkylating agent therapy. Median stem cell collection was 4.88 x 10(6) CD34+ cells/kg per apheresis and 44 patients collected >5 x 10(6) CD34+ cells/kg within 2 days. In 36 patients, more than 10 x 10(6) CD34+ cells/kg were collected including 33 patients who required 1-2 days of collection. One patient required hospitalization for fever/neutropenia and two required weekend apheresis. We conclude that 1.5 g/m(2) cyclophosphamide plus 10 microg/kg G-CSF is a safe, effective, highly predictable mobilizing program that uniformly provided enough stem cells for one transplant and enough stem cells for two transplants.

Allogeneic peripheral blood stem cell transplantation for high-risk non-Hodgkin's lymphoma

A high incidence of nonrelapse mortality (NRM) has limited the use of allogeneic transplantation for poor prognosis non-Hodgkin's lymphoma (NHL). We sought to improve the outcome of allografting by utilizing Filgrastim-mobilized peripheral blood stem cells (PBSC) in combination with either standard ablative or reduced-intensity conditioning. A total of 21 patients with intermediate/high-grade lymphoma and seven patients with low-grade histology were enrolled on protocols using PBSC. All patients were considered high risk for recurrence and/or NRM because of age >50 (n=16), refractory disease (n=17), failed autologous transplant (n=11) and abnormal organ function (n=2). In all, 17 patients received ablative regimens and 11 received modified conditioning including fludarabine, intravenous busulfan and ATG. Tacrolimus and mini-dose methotrexate were used for graft-versus-host-disease (GVHD) prophylaxis. Median follow-up was 38 months. Disease-free and overall survival were 57 and 58%. Seven of the 11 patients who relapsed after a previous transplant remain disease free. Four of the 10 patients with recurrent/persistent disease post transplant responded to additional therapy including withdrawal of immunosuppression+/-DLI. These results support a potent graft-versus-lymphoma effect and suggest that patients who relapse after an autologous transplant can be salvaged with an allogeneic transplant.

What can analysis of calls to NHS direct tell us about the epidemiology of gastrointestinal infections in the community?

OBJECTIVES

Most gastrointestinal (GI) illness within the UK goes undetected by routine surveillance. A national telephone helpline for health advice (NHS Direct) offers a new source of data on GI infection. We aim to describe NHS Direct calls suggestive of GI infection and the outcome of these calls.

METHODS

Details of over 150000 telephone calls were collected from NHS Direct over a 6-month period. Calls about 'diarrhoea', 'vomiting' or 'food poisoning' were defined as GI calls and described according to the age of the patient and call outcome.

RESULTS

Gastrointestinal calls accounted for 10.3% of total calls ('diarrhoea'=4.9%, 'vomiting'=5.1%). GI calls as a proportion of total calls were significantly high in children under 1 year (23.5%) and aged 1-4 years (21.5%). Call outcomes which resulted in further NHS care being recommended accounted for 72.3% of total calls and 54.5% of GI calls.

CONCLUSIONS

A high proportion of NHS Direct calls were about GI symptoms especially for children under 5 years. When compared with all NHS Direct calls, GI calls were less likely to result in further NHS care being recommended. Analysis of NHS Direct calls provides further insight into GI infection in the community.

Use of NHS Direct calls for surveillance of influenza--a second year's experience

A second year's call data to NHS Direct are presented to evaluate their usefulness for influenza surveillance. During the winter of 2000-01, age-group-specific data relating to the 'cold/flu' algorithm were collected from six NHS Direct sites (population coverage: 16 million). The total number of calls was collected from all 23 NHS Direct sites on a daily basis. Despite the winter of 2000-01 having been a season of low activity for influenza in the United Kingdom, NHS Direct data demonstrated a peak in the 'cold/flu' calls as a proportion of the total calls (3.1% [672 'cold/flu' calls] during week 06/01). This coincided with the peak recorded by routine influenza surveillance systems. There was also an earlier peak in the proportion of 'cold/flu' calls (3.3% during weeks 52/00 [789 'cold/flu' calls] and 01/01 [749 'cold/flu' calls]) which may have been due to other respiratory infections, the lack of specificity of the definition of NHS Direct 'cold/flu' calls and an increase in 'out-of-hours' calls to NHS Direct at the time. Despite limitations, the timeliness of NHS Direct data, the total population coverage of the service and the ability to provide local information on 'cold/flu' calls make the call data suitable for further surveillance during the winter of 2001-02. It is hoped that as NHS Direct reaches a 'steady state' in terms of population coverage and uniformity of clinical support systems, it will be possible to begin to construct 'baselines' for the respiratory disease related call data.

Phase II trial of 9-aminocamptothecin as a 72-h infusion in cutaneous T-cell lymphoma

PURPOSE

To evaluate the role of 9-aminocamptothecin (9-AC), a synthetic camptothecin analog, in advanced cutaneous T-cell lymphoma (CTCL).

METHODS

Eligible patients had stage IIB-IV CTCL. 9-AC was infused over 72 h at a dose of 1,100 microg/m2 per day (approximately 46 microg/m2/h) every 2 weeks, with granulocyte-colony stimulating factor (G-CSF) support.

RESULTS

Twelve patients received a total of 30 cycles of 9-AC. Nine patients had stage IV disease, 5 patients had circulating Sezary cells, and 2 patients had evidence of tranformation to a large cell lymphoma. Most of the patients were heavily pretreated: 10 had received prior chemotherapy (83%), 5 of whom had received 2 or more prior regimens, including a patient who had received high-dose chemotherapy, and 7 had previously received total-skin electron beam therapy. The study was prematurely terminated due to substantial toxicity. Six patients (50%) developed an indwelling central venous catheter-related infection, 5 during a period of neutropenia. Three patients died due to sepsis 4-8 weeks after their last 9-AC treatment. Two of these patients had a previous history of bacterial sepsis. Four patients (33%) developed grade IV thrombocytopenia. Two partial responses were observed (response rate 17%), but the duration of response was brief, 4-8 weeks.

CONCLUSION

9-AC at this schedule and route of administration had activity but resulted in an unacceptable rate of complicated neutropenia and septic deaths in heavily pretreated patients with advanced CTCL who are susceptible to catheter-related infections.

Modern valence-bond description of chemical reaction mechanisms: the 1,3-dipolar addition of diazomethane to ethene

The electronic mechanism for the gas-phase concerted 1,3-dipolar cycloaddition of diazomethane (CH2N2) to ethene (C2H4) is described through spin-coupled (SC) calculations at a sequence of geometries along the intrinsic reaction coordinate obtained at the MP2/6-31G(d) level of theory. It is shown that the bonding rearrangements occurring during the course of this reaction follow a heterolytic pattern, characterized by the movement of three well-identifiable orbital pairs, which are initially responsible for the pi bond in ethene and the C-N pi bond and one of the N-N pi bonds in diazomethane and are retained throughout the entire reaction path from reactants to product. Taken together with our previous SC study of the electronic mechanism of the 1,3-dipolar cycloaddition of fulminic acid (HCNO) to ethyne (C2H2) (Theor. Chim. Acc. 1998, 100, 222), the results of the present work suggest strongly that most gas-phase concerted 1,3-dipolar cycloaddition reactions can be expected to follow a heterolytic mechanism of this type, which does not involve an aromatic transition state. The more conventional aspects of the gas-phase concerted 1,3-dipolar cycloaddition of diazomethane to ethene, including optimized transition structure geometry, electronic activation energy, activation barrier corrected for zero-point energies, standard enthalpy, entropy and Gibbs free energy of activation, have been calculated at the HF/6-31G(d), B3LYP/6-31G(d), MP2/6-31G(d), MP2/6-31G(d,p), QCISD/6-31G(d) and CCD/6-31G(d) levels of theory. We also report the CCD/6-311++G(2d, 2p)//CCD/6-31G(d), MP4(SDTQ)/6-311++G(2d,2p)//CCD/6-31G(d) and CCSD(T)/6-311++G(2d, 2p)//CCD/6-31G(d) electronic activation energies.

P-glycoprotein expression and multidrug resistance in cutaneous T-cell lymphoma

Advanced-stage cutaneous T-cell lymphoma (CTCL) is generally resistant to standard chemotherapy. Because P-glycoprotein (P-gp) has been detected in other types of resistant solid tumors, leukemias, and lymphomas, we analyzed P-gp expression in CTCL. Twenty-seven patients with CTCL and circulating Sezary cells in the peripheral blood as observed on a peripheral smear treated at the Yale Photopheresis Center between 1987 and 1993 were identified. Twenty-five of these patients had skin biopsies evaluated for expression of P-gp using JSB-1 (Accurate Chemical), MRK-16 (gift of T. Tsuruo), and UIC-2 (gift of E. Metchner). P-gp expression was considered present if immunoreactivity was noted with two of the three antibodies. Eighteen of 25 patients (72%) evaluated exhibited expression. The patients were treated with various combinations of drugs consisting of topical and systemic steroids electron beam therapy, psoralens in combination with UV light A (PUVA), systemic chemotherapy, and photopheresis before testing the tissue for P-gp expression. Treatment with systemic chemotherapy in P-gp-positive patients produced responses in 3 and no responses in 11 patients (4 were lost to follow-up). Seven patients did not express P-gp: One patient responded to treatment, five did not respond, and one patient was lost to follow-up. These results demonstrate that P-gp is frequently expressed in CTCL. P-gp expression in our study was not a useful predictor of drug resistance.

In vitro collection and posttransfusion engraftment characteristics of MNCs obtained by using a new separator for autologous PBPC transplantation

BACKGROUND

A clinical study was performed to evaluate the peripheral blood progenitor cell (PBPC) collection, transfusion, and engraftment characteristics associated with use of a blood cell separator (Amicus, Baxter Healthcare).

STUDY DESIGN AND METHODS

Oncology patients (n = 31) scheduled for an autologous PBPC transplant following myeloablative therapy were studied. PBPCs were mobilized by a variety of chemotherapeutic regimens and the use of G-CSF. As no prior studies evaluated whether PBPCs collected on the Amicus separator would be viable after transfusion, to ensure patient safety, PBPCs were first collected on another cell separator (CS-3000 Plus, Baxter) and stored as backup. The day after the CS-3000 Plus collections were completed, PBPC collections intended for transfusion were performed using the Amicus instrument. For each transplant, >2.5 x 10(6) CD34+ PBPCs per kg of body weight were transfused.

RESULTS

Clinical data collected on the donors immediately before and after PBPC collection with the Amicus device were comparable to donor data similarly obtained for the CS-3000 Plus collections. While the number of CD34+ cells and the RBC volume in the collected products were equivalent for the two devices, the platelet content of the Amicus collections was significantly lower than that of the CS-3000 Plus collections (4.35 x 10(10) platelets/bag vs. 6.61 x 10(10) platelets/bag, p<0.05). Collection efficiencies for CD34+ cells were 64 +/- 23 percent for the Amicus device and 43 +/- 14 percent for the CS-3000 Plus device (p<0.05). The mean time to engraftment for cells collected via the Amicus device was 8.7 +/- 0.7 days for >500 PMNs per microL and 9.7 +/- 1.5 days to attain a platelet count of >20,000 per microL-equivalent to data in the literature. No CS-3000 Plus backup cells were transfused and no serious adverse events attributable to the Amicus device were encountered.

CONCLUSIONS

The mean Amicus CD34+ cell collection efficiency was better (p<0.05) than that of the CS-3000 Plus collection. Short-term engraftment was durable. The PBPCs collected with the Amicus separator are safe and effective for use for autologous transplant patients requiring PBPC rescue from high-dose myeloablative chemotherapy.

High-dose BEAM chemotherapy with autologous peripheral blood progenitor-cell transplantation for unselected patients with primary refractory or relapsed Hodgkin's disease

BACKGROUND

The use of autologous peripheral blood progenitor cells (PBPC) expedites hematologic recovery and reduces the costs of transplantation in comparison with autologous bone marrow; however, its efficacy in patients with Hodgkin's disease has been questioned. We evaluated the results of autologous PBPC transplantation in a population of unselected and uniformly treated patients with primary refractory or relapsed Hodgkin's disease.

PATIENTS AND METHODS

Forty consecutive adult patients with primary refractory (n = 7) or relapsed (n = 33) Hodgkin's disease received high-dose BEAM (BCNU, etoposide, ara-C, and melphalan) followed by autologous PBPC infusion. Twenty-four patients (60%) received high-dose BEAM as outpatients. Consolidative radiation therapy was administered to 14 patients (35%).

RESULTS

Thirty-seven patients (92%) achieved a post transplant complete response. The 3-year progression-free survival (PFS) was 69%, and the 3-year overall survival (OS) was 77%, with a median follow-up of surviving patients of 28 months. Severe non-hematologic toxicities included gastrointestinal side effects (diarrhea 17%, mucositis 25%), and interstitial pneumonitis (15%). One patient died of acute transplant-related complications (mortality rate 2.5%). Strong predictors of poor PFS were chemoresistant versus chemosensitive/untested disease (actuarial PFS 89% versus 22%, P = 0.0000) and stage IIB-IV versus I-IIA at relapse/progression (86%, versus 46%, P = 0.005). All five patients with elevated lactate dehydrogenase at the time of transplantation died of their disease. There was a trend toward worse PFS for patients receiving a higher number of CD34+ cells (> or = 11 x 10(6) per kg).

CONCLUSIONS

High-dose BEAM chemotherapy with autologous PBPC transplantation is associated with low mortality and results in satisfactory PFS for patients with primary refractory or relapsed Hodgkin's disease. The subset of patients with progressive disease at the time of transplantation performs poorly and may benefit from alternative strategies.

Use of rituximab and irradiated donor-derived lymphocytes to control Epstein-Barr virus-associated lymphoproliferation in patients undergoing related haplo-identical stem cell transplantation

Epstein-Barr virus-associated lymphoproliferative disorder (EBV-LPD) is an uncommon but potentially fatal complication of allogeneic stem cell transplantation. We report here two patients who underwent T cell-depleted mismatched-related stem cell transplantation for hematologic malignancies and required aggressive post-transplant immunosuppression for graft-versus host disease (GVHD). Both patients subsequently developed markedly elevated EBV-DNA titers in association with monoclonal, light chain-restricted B cell populations in the blood. Although immunosuppressive medications were rapidly tapered, neither patient could receive potentially curative therapy with unmanipulated donor-derived lymphocyte infusions (DLI) because of the substantial risk of severe GVHD. Therefore, both patients received repeated courses of rituximab, an anti-CD20 monoclonal antibody, in combination with irradiated DLI. This therapeutic strategy resulted in normalization of the elevated EBV-DNA titers and disappearance of the monoclonal B cell populations. Our results suggest that rituximab and possibly irradiated DLI played an important role in controlling early EBV-LPD in these two patients and may be an effective alternative therapeutic strategy for patients who develop EBV-LPD post transplant and are unable to receive unmanipulated DLI.

Differential expressions of CD44 variants in tumors affecting the central nervous system

BACKGROUND

The polymorphic cell adhesion molecule CD44 exists as a family of proteins generated by extensive alternative splicing of the CD44 pre-messenger RNA and marked posttranslational modification. The differential expression of CD44 isoforms in a variety of human cancers has been proposed to influence tumorigenesis and metastasis. In this study, CD44 gene expression was analyzed in primary and metastatic tumors and in cell lines derived from tumors that affect the central nervous system (CNS), including tumors metastatic to the spine.

MATERIALS AND METHODS

Fifty-four samples were subjected to semiquantitative reverse-transcriptase polymerase chain reaction with CD44-specific primers and hybridized individually with probes specific for the CD44 variant (CD44v) exons v3 to v10.

RESULTS

Compared with CD44v-positive breast cancer cell lines and CD44v-negative normal brain tissue, CD44v expression was weak in primary brain tumors and cell lines derived from normal brain and tumor tissue. However, high levels of isoforms encoding multiple-variant exons were shown in all metastatic brain tumors. In contrast, tumors metastatic to the spine were virtually negative for CD44v expression. Several rare CD44 isoforms composed of single-variant exons v3, v4, v6, or v9 were identified in primary brain tumors and may reflect their invasive potential or culturability in vitro.

CONCLUSION

These data suggest differential expression of CD44v may substantially influence the end-organ site of metastasis for tumor cells destined for the CNS.

Alternatively spliced CD44 isoforms containing exon v10 promote cellular adhesion through the recognition of chondroitin sulfate-modified CD44

Correlations have been noted between the expression of certain alternatively spliced CD44 isoforms and the metastatic propensity of various histologically distinct tumor cell types. The precise mechanism by which particular CD44 isoforms contribute to the metastatic process is, however, unclear. In the present study we demonstrate that CD44R2, a CD44 isoform highly expressed on activated and transformed hemopoietic cells, can recognize and bind a common determinant present on CD44H and CD44R1. Importantly, CD44H lacked this activity. Pretreatment of TIL1 cells expressing CD44H or CD44R1 with chondroitinase ABC inhibited adhesion to CD44R2, suggesting that the unique inserted region present within the CD44R2 molecule, encoded by exon v10, mediates cell adhesion by potentiating the recognition of chondroitin sulfate moieties presented in association with other CD44 molecules. These data help explain the differential involvement of v10-containing CD44 isoforms in tumor metastasis.

Assessment of cardiac and pulmonary function in adult patients with Hodgkin's disease treated with ABVD or MOPP/ABVD plus adjuvant low-dose mediastinal irradiation

We evaluated the long-term effects of combined modality therapy (CMT) with adriamycin, bleomycin, vinblastine, dacarbazine (ABVD) or mechlorethamine, vincristine, prednisone, procarbazine (MOPP)/ABVD plus adjuvant low-dose (< 30 Gy) involved-field radiation therapy (LDRT) on cardiac and pulmonary functions in adult patients with Hodgkin's disease (HD). Adjuvant LDRT (mean dose, 2340 cGy) to the mediastinum was administered to 24 patients after chemotherapy with MOPP/ABVD (n = 10) and ABVD (n = 14). The mean doses of doxorubicin and bleomycin were 233 mg/m2 and 92 IU/m2, respectively. Cardiac and pulmonary function tests were performed in all patients and, when available, were compared with pretreatment studies. After a median follow-up of 6.3 years, none of the patients had cardiac or pulmonary symptoms. A 4.7% overall decrease in left ventricular ejection fraction (LVEF) was observed (p = 0.03), but only one patient had a mildly decreased LVEF (47%). Diastolic function, LVEF, and left ventricular volume remained within the normal range in the other 23 patients. Mild pulmonary function study abnormalities occurred in 8 of 24 patients, 6 of whom were cigarette smokers. There were no significant changes in total lung capacity and forced vital capacity (FVC) values, but there was a 3% overall decrease in FEV1/FVC ratio (p = 0.05). In adult patients with HD, adjuvant LDRT after chemotherapy with ABVD or MOPP/ABVD did not result in a significant incidence of permanent pulmonary or cardiac toxicity after more than 6.3 years of median follow-up. Further studies are warranted to fully evaluate the impact of such therapy on cardiopulmonary function.

Neutropenic infections in 100 patients with non-Hodgkin's lymphoma or Hodgkin's disease treated with high-dose BEAM chemotherapy and peripheral blood progenitor cell transplant: out-patient treatment is a viable option

A retrospective analysis was performed on 100 patients with non-Hodgkin's lymphoma (NHL, n = 75) or Hodgkin's disease (HD, n = 25) who underwent peripheral blood progenitor cell transplant (PBPCT) following high-dose chemotherapy (HDCT) with BCNU, etoposide, cytarabine and melphalan (BEAM) between March 1994 and June 1997. Following PBPCT and until engraftment all patients received oral ciprofloxacin and fluconazole, patients with positive Herpes simplex virus serology received acyclovir and 91 patients received filgrastim. The median days of neutropenia and days to an absolute neutrophil count (ANC) >500/mm3 were 6 and 9, respectively. Febrile neutropenia occurred in 68 patients. Gram-positive bacteremia occurred in 14 patients. No gram-negative infections, invasive fungal infections, intensive care visits or deaths occurred during the period of neutropenia or in the first 30 days following transplant. In multivariate logistic regression the risk of development of any infection was associated only with the duration of neutropenia (P = 0.02) and the risk of bacteremia was associated only with the number of CD34+ cells infused (P = 0.046). Among 49 patients treated in the outpatient setting, 14 (28%) were never admitted. High-dose chemotherapy with BEAM supported by PBPCT, prophylactic antibiotics and filgrastim resulted in a low incidence of infections and no acute mortality. WBC engraftment occurred rapidly allowing for a predictable course during which lengthy hospital stays and amphotericin therapy could be avoided.

A phase I study of paclitaxel for mobilization of peripheral blood progenitor cells

We conducted a phase I trial to determine the dose and schedule of paclitaxel, when given together with filgrastim, which would optimally promote mobilization of stem cells with tolerable toxicity. Dose escalation began at 275 mg/m2 3 h infusion. Dose-limiting neuropathy was observed at the 300 mg/m2 dose level. A second dose escalation was conducted utilizing 24 h infusion schedules, beginning at 225 mg/m2. Dose escalation was continued by 25 mg/m2 increments to 300 mg/m2, at which dose neuropathy was again dose-limiting. The recommended dose and schedule of paclitaxel for the purpose of mobilization of stem cells, when given together with filgrastim, are 275 mg/m2 as a 24 h infusion. The median stem cell yield after this dose of paclitaxel was 6.6 x 10(6) CD34+ cells/kg/apheresis (range 3.6 x 10(6)-7.7 x 10(6)).

CD44V6 expression in human colorectal carcinoma

CD44 is an adhesion molecule involved in cell-to-cell and cell-to-matrix interactions. This transmembrane glycoprotein exists in either standard or variant forms, originated by alternative splicing. One of the isoforms (CD44V6) has been shown, in some systems, to modify the metastatic potential of tumor cells. To investigate the role of this biomarker as possible prognostic antigen in colorectal cancer, we immunohistochemically analyzed the distribution of CD44V6 expression on formalin-fixed, paraffin-embedded tissues from resected colorectal cancers of 34 patients. The monoclonal antibody VFF7 against the amino acid sequence encoded by exon CD44V6 was applied using the avidin-biotin-peroxidase method. For each resected specimen, normal (N), adenomatous (AD), and carcinomatous (CA) colonic mucosa were tested. In 68% of the resected cases, these areas were present in the same slide, and in 76% of cases, nodal or liver metastases (MT) were available for evaluation. Adenomatous polyp biopsy specimens of 10 carcinoma-free patients were also tested. In selected cases, CD44V6 expression was also determined using the Western blot immunoprecipitation technique. CD44V6 immunoreactivity was detected in 100% of the ADs, and in 91% of CAs, but was mostly weak in only 38% of MTs (n=26). In 49% (n=35) of ADs, 11% (n=34) of CAs, and 4% of MTs (n=26), the stain was moderate to strong. CD44V6 immunoreactivity was predominantly membranous in ADs and cytoplasmic in MTs. In the CAs, both staining patterns were noted. Interestingly, the normal mucosa had a weak subnuclear localization of the stain. In the cases evaluated by Western blotting immunoprecipitation analysis, the level of CD44V6 protein expression was similar to that obtained by immunohistochemistry. No correlation was found with tumor type, stage, or patient survival. The predominant CD44V6 expression in ADs and CAs, but not in MTs, suggests that, in many cases, the expression of this adhesion molecule may be lost during the acquisition of migratory function by the tumor cells.