Coproduction of Low-Barrier Hepatitis C Virus and HIV Care for People Who Use Drugs in a Rural Community: Brief Qualitative Report

BACKGROUND

People who inject drugs are experiencing syndemic conditions with increasing risk of infection with hepatitis C (HCV) and HIV. However, rates of accessing HCV and HIV testing and treatment among people who inject drugs are low for various reasons, including the criminalization of drug use, which leads to a focus on treating drug use rather than caring for drug users. For many people who inject drugs, health care becomes a form of structural violence, resulting in traumatic experiences, fear of police violence, unmet needs, and avoidance of medical care. There is a clear need for novel approaches to health care delivery for people who inject drugs.

OBJECTIVE

This study aimed to analyze the process of a multidisciplinary team-encompassing health care professionals, community representatives, researchers, and people with lived experience using drugs-that was formed to develop a deep understanding of the experiences of people who inject drugs and local ecosystem opportunities and constraints to inform the cocreation of low-barrier, innovative HCV or HIV care in a rural community. Given the need for innovative approaches to redesigning health care, we sought to identify challenges and tensions encountered in this process and strategies for overcoming these challenges.

METHODS

Analysis was based on an in-depth review of meeting notes from the project year, followed by member-checking with the project team to revise and expand upon the challenges encountered and strategies identified to navigate these challenges.

RESULTS

Challenges and tensions included: scoping the project, setting the pace and urgency of the work, adapting to web-based work, navigating ethics and practice of payment, defining success, and situating the project for sustainability. Strategies to navigate these challenges included: dedicated effort to building personal and meaningful connections, fostering mutual respect, identifying common ground to make shared decisions, and redefining successes.

CONCLUSIONS

While cocreated care presents challenges, the resulting program is strengthened by challenging assumptions and carefully considering various perspectives to think creatively and productively about solutions.

Choosing wisely in burn care

BACKGROUND

The Choosing Wisely Campaign was launched in 2012 and has been applied to a broad spectrum of disciplines in almost thirty countries, with the objective of reducing unnecessary or potentially harmful investigations and procedures, thus limiting costs and improving outcomes. In Canada, patients with burn injuries are usually initially assessed by primary care and emergency providers, while plastic or general surgeons provide ongoing management. We sought to develop a series of Choosing Wisely statements for burn care to guide these practitioners and inform suitable, cost-effective investigations and treatment choices.

METHODS

The Choosing Wisely Canada list for Burns was developed by members of the Canadian Special Interest Group of the American Burn Association. Eleven recommendations were generated from an initial list of 29 statements using a modified Delphi process and SurveyMonkey™.

RESULTS

Recommendations included statements on avoidance of prophylactic antibiotics, restriction of blood products, use of adjunctive analgesic medications, monitoring and titration of opioid analgesics, and minimizing 'routine' bloodwork, microbiology or radiological investigations.

CONCLUSIONS

The Choosing Wisely recommendations aim to encourage greater discussion between those involved in burn care, other health care professionals, and their patients, with a view to reduce the cost and adverse effects associated with unnecessary therapeutic and diagnostic procedures, while still maintaining high standards of evidence-based burn care.

P2262Intensity and cost of health care at the end of life among patients with heart failure

Background

Health care utilization increase towards the end of life. There is little known about the intensity of care, including use of in-hospital services, critical care units, and invasive procedures at the end of life in heart failure (HF).

Aims

To determine the type and intensity of health care services offered at the end of life to patients with HF, and to establish the determinants of and costs associated with death in the hospital versus at home.

Methods

We conducted a retrospective cohort study of adults (≥18 years) who died between April 1, 2004 and March 31, 2017 in Ontario, Canada. We included decedents with a diagnosis of HF in the 2 years preceding their death and a hospitalization for HF in their last year of life. We obtained demographic, clinical, healthcare utilization, and healthcare cost data from population-based administrative databases, using unique encrypted identifiers to link records. We calculated direct costs from the perspective of the Ministry of Health in our publicly-funded healthcare system. We used descriptive statistics and a 2-level multivariable logistic regression model) with patients (1st level) nested in regions (2nd level) to assess for predictors of death in the hospital versus at home.

Results

We identified 396,024 adults with HF who died between April 1, 2004 and March 31, 2017. Mean (standard deviation [SD]) age at death was 81.8 (10.7) years, and 48.5% were men. During the last 6 months of life, patients commonly experienced hospitalizations (78.1%), care from >10 different physicians (62.2%); intensive care unit (ICU) admissions (26.4%); mechanical ventilation (18.1%); hemodialysis (6.2%); and cardiac catheterization (3.7%). In the last 6 months of life, patients spent a mean (SD) of 17.4 (23.0) days in the hospital; 2.5 (8.3) days in an ICU; and 1.6 (7.9) days on a ventilator. While the proportion of deaths at home increased from 32.6% in 2004–2005 to 38% in 2016–2017, a majority of patients (53.4%) died in hospital during the study period. Factors independently associated with in-hospital death included age (OR 0.53 [95% CI 0.51–0.55] for age >85 years vs <60 years), sex (OR 0.88 [95% CI 0.87–0.89] for female vs male), and socioeconomic status (OR 0.87 [95% CI 0.85–0.89] for highest vs lowest income quintile). Palliative care services in the last 6 months of life was associated with higher odds of in-hospital death (OR 1.73 [95% CI 1.70–1.76]). Death in hospital was associated with higher mean [SD] healthcare costs in the terminal 6 months of life than death out of hospital ($52,349 [55,649] vs $35,943 [31,907]).

Conclusion

In this large cohort study in Ontario, Canada, patients with HF commonly received in-hospital, intensive, and invasive care in the last 6 months of life, and a majority of patients died in hospital. Death in hospital was associated with higher costs of care in the terminal 6 months than death outside hospital.

Acknowledgement/Funding

Heart and Stroke Foundation of Ontario, Canadian Institutes of Health Research

P3519Sex-based disparities in end of life care among patients with heart failure

Background

There are sex-based disparities in care and outcomes among patients with heart failure (HF), but the association between sex and health care services received at the end-of-life health is unknown.

Purpose

To assess for sex-based differences in location of death and the type and intensity of health care services received at the end of life among patients with HF.

Methods

We conducted a retrospective cohort study of adults (≥18 years) who died between April 1, 2004 and March 31, 2017 in Ontario, Canada. We included decedents who had a diagnosis of HF and a hospitalization for HF in the year preceding their death. We obtained demographic, clinical, health care utilization, and healthcare system cost data from population-based administrative databases, using unique encrypted identifiers to link records. We used descriptive statistics and a 2-level multivariable logistic regression model with patients (1st level) nested in regions (2nd level) to assess whether sex was independently associated with death in hospital.

Results

We identified 396,024 adults (51.5% women) who died of HF between April 1, 2004 and March 31, 2017. Mean (SD) age at death was 81.8 (10.7) years and a majority of deaths (53.4%) occurred in the hospital. During the last 6 months of life, a significantly lower proportion of women than men experienced emergency department visits (81.7% vs 86.5%; p<0.001); hospitalizations (75.6% vs 80.8%; p<0.001); intensive care unit (ICU) admissions (22.8% vs 30.1%; p<0.001); mechanical ventilation (15.5% vs 20.8%; p<0.001); cardiac catheterization (2.8% vs 4.6%; p<0.001); coronary revascularization (1.5% vs 2.6%; p<0.001); hemodialysis (4.8% vs 7.7%; p<0.001); or care from 10 or more different physicians (57.6% vs 67.1%; p<0.001). In the last 6 months of life, women spent fewer days than men in the hospital (mean 16.4 vs 18.3; mean difference [MD] 1.9 [95% confidence interval 1.7–2.0]; p<0.001), in an ICU (mean 2.1 vs 3.0; MD 0.9 [95% CI 0.8–0.9]; p<0.001), and on a ventilator (mean 1.4 vs 1.9; MD 0.5 [95% CI 0.5–0.5]; p<0.001). These differences persisted and remained significant in the last month of life. There was no difference in the proportion of women vs men receiving palliative care services (45.1% vs 45.0%; p=0.53) in the last 6 months of life. After adjusting for age, socioeconomic status, comorbidities, place of residence, and year of death, women had lower odds of dying in a hospital than men (adjusted odds ratio 0.88 [95% CI 0.87–0.89]).

Conclusion

In this large cohort study in Ontario, Canada, women with HF received disproportionately lower in-hospital and invasive care services than men in their last 6 months of life and were more likely than men to die at home.

Acknowledgement/Funding

Canadian Institutes of Health Research

Genetic Characterization of Resistance to Pyrenophora teres f. teres in the International Barley Differential Canadian Lake Shore

Genetic resistance to net form of net blotch in the international barley differential Canadian Lake Shore (CLS) was characterized and mapped. A doubled haploid (DH) population generated from a cross between CLS and susceptible cultivar Harrington was evaluated at the seedling stage using eight diverse Pyrenophora teres f. teres (Ptt) isolates and at the adult stage in the field using natural inoculum. To effectively map the CLS resistance, comparative marker frequency analysis (MFA) was performed using 8,762 polymorphic DArT-seq markers, where 'resistant' and 'susceptible' groups each comprised 40 DH lines displaying the most extreme phenotypes. Five DArTseq markers were consistently detected in eight disease assays, which was designated qPttCLS and deemed to harbor the locus underpinning CLS resistance. Four of these markers were present onto the barley DArTseq physical map and spans a region between 398203862 and 435526243 bp which were found to consist several genes involved in important plant functions such as disease response and signaling pathways. While MFA only detected the 3H region, genetic analyses based on segregation patterns were inconsistent, suggesting complex inheritance or variation in phenotypic expression of qPttCLS, particularly in the field. This study represents progress toward connecting Ptt pathotype surveys with the corresponding resistance genes in barley differentials. The markers associated with qPttCLS are useful for marker-assisted selection in breeding programs.

Abstract P4-09-06: Analyzing the changes in the HR+/HER2- metastatic breast cancer (mBC) landscape since the arrival of CDK4/6 inhibitors with machine learning and visual analytics

BACKGROUND: The real-world impact of CDK4/6 inhibitor use on HR+/HER2- mBC treatment sequencing, treatment response, and therapeutic utilization is limited. This study sought to describe treatment sequencing and response pre- and post-FDA approval of CDK4/6 inhibitors by conducting a traditional observational study approach and supplementing with a machine-learning methodology.

METHODS: Female patients ≥18yrs were identified in the MarketScan Commercial and Medicare Supplement databases with continuous enrollment for at least 12 months pre-index, ≥2 medical claims for a BC diagnosis and ≥2 medical claims for metastatic disease (earliest=index date), and who had no treatment at any time with HER2 targeted therapy. Patients were excluded if they had received CDK4/6 or everolimus treatment prior to index. Treatment was stratified by line of therapy pre- and post- first CDK4/6 approval (February 3, 2015). We identified treatment patterns with standard distributions and visual analytics. Response to therapy and utilization was analyzed with prediction models and IBM Watson® machine learning population comparison models.

RESULTS: A total of 19,558 patients were eligible for the study with a mean age at diagnosis of mBC of 62 (SD 13). Prior to first CDK4/6 inhibitor approval, anastrazole and letrozole monotherapies were most likely to be identified as both first and second line treatment. Following approval of the first CDK4/6 inhibitor in 2015, CDK4/6 inhibitors were observed as a first line treatment in 25% of patients, and as second line treatment in 24% of patients. Of patients diagnosed following the first CDK4/6 inhibitor approval, 44% of patients were exposed to endocrine therapy and 10% were exposed to chemotherapy in the pre-index period. Patients receiving CDK4/6 inhibitors in combination with endocrine therapy as first line treatment were observed to have a longer progression free survival time than patients receiving endocrine monotherapy. Visual analytics demonstrate a large variation in treatment sequencing, especially after first line therapy. Machine learning and prediction models identified a strong secular bias in the use of CDK4/6 and a signal for improved treatment response in patients with no exposure to endocrine therapies in the pre-index period.

CONCLUSIONS: The mBC treatment landscape has changed significantly with the introduction of CDK4/6 inhibitors, which may be expected to impact long-term outcomes. Visual analytics and machine learning approaches can improve clinical insight. These approaches can help with identifying patient and clinical characteristics that predict response and utilization as well as appropriate treatment selections across lines of therapy.

Citation Format: Meade D, Hensley Alford S, Mahatma S, Malangone-Monaco E, Boulanger L, Tkacz J, Turner SJ, Chen S, Manson S, Mejia S, Buleje I, Madan P, Kim G, Fowler R, Basar A. Analyzing the changes in the HR+/HER2- metastatic breast cancer (mBC) landscape since the arrival of CDK4/6 inhibitors with machine learning and visual analytics [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-09-06.

The use of hypnosis for pain relief for patients with polyradiculoneuritis

At the Royal Perth Hospital, pain during physiotherapy range of movement and muscle stretching exercises has been a significant problem for some patients who have had polyradiculoneuritis, otherwise known as the Guillain-Barré Syndrome (GBS). Anxiety often accompanies GBS and can exacerbate the experience of pain. Regular analgesics have failed to adequately control the patients' pain such that full range of movement has been impossible and soft tissue shortening has occurred. Recently, alternative pain control in the form of hypnotherapy has been used during physiotherapy sessions. Two case studies are presented as examples of the use of hypnotherapy at the Royal Perth Hospital. These describe the benefit of hypnotherapy for pain control in some patients who have GBS.

Epidemiology of influenza-associated hospitalization in adults, Toronto, 2007/8

The purpose of this investigation was to identify when diagnostic testing and empirical antiviral therapy should be considered for adult patients requiring hospitalization during influenza seasons. During the 2007/8 influenza season, six acute care hospitals in the Greater Toronto Area participated in active surveillance for laboratory-confirmed influenza requiring hospitalization. Nasopharyngeal (NP) swabs were obtained from patients presenting with acute respiratory or cardiac illness, or with febrile illness without clear non-respiratory etiology. Predictors of influenza were analyzed by multivariable logistic regression analysis and likelihoods of influenza infection in various patient groups were calculated. Two hundred and eighty of 3,917 patients were found to have influenza. Thirty-five percent of patients with influenza presented with a triage temperature >or=38.0 degrees C, 80% had respiratory symptoms in the emergency department, and 76% were >or=65 years old. Multivariable analysis revealed a triage temperature >or=38.0 degrees C (odds ratio [OR] 3.1; 95% confidence interval [CI] 2.3-4.1), the presence of respiratory symptoms (OR 1.7; 95% CI 1.2-2.4), admission diagnosis of respiratory infection (OR 1.8; 95% CI 1.3-2.4), admission diagnosis of exacerbation of chronic obstructive pulmonary disease (COPD)/asthma or respiratory failure (OR 2.3; 95% CI 1.6-3.4), and admission in peak influenza weeks (OR 4.2; 95% CI 3.1-5.7) as independent predictors of influenza. The likelihood of influenza exceeded 15% in patients with respiratory infection or exacerbation of COPD/asthma if the triage temperature was >or=38.0 degrees C or if they were admitted in the peak weeks during the influenza season. During influenza season, diagnostic testing and empiric antiviral therapy should be considered in patients requiring hospitalization if respiratory infection or exacerbation of COPD/asthma are suspected and if either the triage temperature is >or=38.0 degrees C or admission is during the weeks of peak influenza activity.

Outreach and Early Warning Systems (EWS) for the prevention of intensive care admission and death of critically ill adult patients on general hospital wards

BACKGROUND

Despite the fact that outreach and early warning systems (EWS) are an integral part of a hospital wide systems approach to improve the early identification and management of deteriorating patients on general hospital wards, the widespread implementation of these interventions in practice is not based on robust research evidence.

OBJECTIVES

The primary objective was to determine the impact of critical care outreach services on hospital mortality rates. Secondary objectives included determining the effect of outreach services on intensive care unit (ICU) admission patterns, length of hospital stay and adverse events.

SEARCH STRATEGY

The review authors searched the following electronic databases: EPOC Specialised Register, The Cochrane Central Register of Controlled Trials (CENTRAL) and other Cochrane databases (all on The Cochrane Library 2006, Issue 3), MEDLINE (1996-June week 3 2006), EMBASE (1974-week 26 2006), CINAHL (1982-July week 5 2006), First Search (1992-2005) and CAB Health (1990-July 2006); also reference lists of relevant articles, conference abstracts, and made contact with experts and critical care organisations for further information.

SELECTION CRITERIA

Randomised controlled trials (RCTs), controlled clinical trials (CCTs), controlled before and after studies (CBAs) and interrupted time series designs (ITS) which measured hospital mortality, unanticipated ICU admissions, ICU readmissions, length of hospital stay and adverse events following implementation of outreach and EWS in a general hospital ward to identify deteriorating adult patients versus general hospital ward setting without outreach and EWS were included in the review.

DATA COLLECTION AND ANALYSIS

Three review authors independently extracted data and two review authors assessed the methodological quality of the included studies. Meta-analysis was not possible due to heterogeneity. Summary statistics and descriptive summaries of primary and secondary outcomes are presented for each study.

MAIN RESULTS

Two cluster-randomised control trials were included: one randomised at hospital level (23 hospitals in Australia) and one at ward level (16 wards in the UK). The primary outcome in the Australian trial (a composite score comprising incidence of unexpected cardiac arrests, unexpected deaths and unplanned ICU admissions) showed no statistical significant difference between control and medical emergency team (MET) hospitals (adjusted P value 0.640; adjusted odds ratio (OR) 0.98; 95% confidence interval (CI) 0.83 to 1.16). The UK-based trial found that outreach reduced in-hospital mortality (adjusted OR 0.52; 95% CI 0.32 to 0.85) compared with the control group.

AUTHORS' CONCLUSIONS

The evidence from this review highlights the diversity and poor methodological quality of most studies investigating outreach. The results of the two included studies showed either no evidence of the effectiveness of outreach or a reduction in overall mortality in patients receiving outreach. The lack of evidence on outreach requires further multi-site RCT's to determine potential effectiveness.

Perioperative immunomodulation with Flt3 kinase ligand or a whole tumor cell vaccine is associated with a reduction in lung metastasis formation after laparotomy in mice

INTRODUCTION

Laparotomy has been associated with temporary postoperative immunosuppression and accelerated tumor growth in experimental models. In a previous murine study, a whole cell vaccine plus the adjuvant monophosphoryl-lipid A was shown to be effective in decreasing the number of lung metastases that develop after laparotomy. This study was conducted to assess the impact of the adjuvant fetal liver tyrosine kinase 3 (Flt3) ligand on perioperative tumor growth when used alone or with a tumor cell vaccine.

METHODS

An intravenous tumor cell injection lung metastases model was used. Sixty female A/J mice were divided into six equal groups designated (1) anesthesia control (AC), (2) AC with Flt3 ligand (ACFlt3), (3) sham laparotomy (OP), (4) OP with Flt3 ligand (OPFlt3), (5) OP with vaccine (OPVac), and (6) OP with Flt3 ligand and vaccine (OPFlt3Vac). Groups 2, 4, and 6 received daily intraperitoneal injections of Flt3 ligand (10 microg/dose with carrier) for 5 days before and 5 days after surgery. Groups 1 and 3 received similar injections of saline on the same schedule. Groups 5 and 6 were vaccinated with irradiated whole Ta3Ha tumor cells intraperitoneally three times before and twice after surgery. Immediately after surgery, all mice were injected with 10(5) Ta3Ha tumor cells via a tail vein. After 14 days, the mice were sacrificed and their lungs and tracheas were excised en bloc. Specimens were stained and counterstained with India ink and Fekete solution, and surface metastases were counted by a blinded observer. Differences between study groups were determined by analysis of variance. The peritumoral inflammatory cell infiltrate of some Flt3 and control specimens was also assessed.

RESULTS

Regarding laparotomy, Flt3 ligand (mean, 1.22 metastases), whole cell vaccine (1.12 metastases), and the combination of these two agents (0.1 metastases) were each effective in significantly decreasing the number of surface lung metastases compared with surgery alone (9.88 metastases, P < .05 for all comparisons). There were no differences between the various treatment groups in regards to number of metastases. Only the combination of Flt3 and the vaccine significantly lowered the incidence of tumors (number of mice with > or =1 tumors). Histologic analysis revealed that the Flt3-treated mice demonstrated increased numbers of antigen-presenting cells surrounding the tumors compared with controls.

CONCLUSIONS

Perioperative treatment with either Flt3 ligand or a whole cell tumor vaccine significantly reduced the number of lung metastases after laparotomy. The combination of the Flt3 ligand and the vaccine also decreased the incidence of metastases and was the most effective treatment. Further studies regarding perioperative immune modulation in the setting of cancer appear warranted.

Naturally occurring antibodies to epithelial cell adhesion molecule (EpCAM)

Epithelial cell adhesion molecule (Ep-CAM) is an epithelial tumor-associated antigen that is expressed by a number of normal tissues and has been used as a target in many immunotherapy studies. The purpose of this study was to determine the incidence of serum anti-EpCAM IgG (immunoglobulin G) antibodies in colon cancer and tumor-free patients and to assess the tumor protective value of anti-EpCAM antibodies. One third of both the cancer (16/48) and the control (9/27) patients had detectable antibodies. Although the mean antibody concentration was higher in cancer patients (0.048 +/- 0.120 U) than in controls (0.038 +/- 0.064 U) the difference was not statistically significant. Western blot analysis revealed reactivity to multiple HT29 cell proteins including a 40-kDa protein (presumed to be Ep-CAM). Monoclonal anti-EpCAM 323/A3 antibody did not have a tumor-protective effect in murine Ep-CAM expressing colocarcinoma. We conclude that Ep-CAM is immunogenic not only for cancer patients, but also for tumor-free individuals.

Laparoscopic-assisted cecectomy is associated with decreased formation of postoperative pulmonary metastases compared with open cecectomy in a murine model

BACKGROUND

It was shown in a murine model that sham laparotomy is associated with a higher incidence of postoperative lung metastases when compared with results seen after carbon dioxide pneumoperitoneum. Using the same tumor model, the present study was undertaken to determine if the addition of bowel resection to the operative procedure would impact the results.

METHODS

Sixty mice underwent anesthesia alone (anesthesia control [AC]), laparoscopic-assisted cecectomy (LC), or open cecectomy (OC). After surgery, all animals received tail vein injections of 105 TA3-Ha tumor cells. On postoperative day 14, the lungs and trachea were excised en bloc and processed, and surface lung metastases were counted and recorded by a blinded observer.

RESULTS

The mean number of surface lung metastases in the AC, LC, and OC groups was 30.9, 76.3, and 134.5, respectively. Significantly more metastases were documented after OC (P<.001) and LC (P<.05) than after anesthesia alone. Mice in the LC group had significantly fewer lung metastases (43% less) than mice in the OC group (P<.01).

CONCLUSIONS

OC was associated with significantly more lung metastases than either LC or AC. Surgery-related immune suppression or trophic tumor cell stimulation occurring after surgery may contribute to this phenomenon.

Postoperative cell mediated immune response is better preserved after laparoscopic vs open colorectal resection in humans

BACKGROUND

Animal studies have documented significantly better preserved postoperative cell-mediated immune function, as measured by serial delayed-type hypersensitivity (DTH) challenges, after laparoscopic-assisted than after open bowel resection. Similarly, in humans, the DTH responses after open cholecystectomy have been shown to be significantly smaller than preoperative responses; whereas after laparoscopic cholecystectomy, no significant change in DTH response has been noted. The purpose of this study was to assess cell-mediated immune function via serial DTH skin testing in patients undergoing laparoscopic or open colectomy.

METHODS

A total of 35 subjects underwent either laparoscopic (n = 18) or open colectomy (n = 17) in this prospective but not randomized study. Only patients who were judged to be immunoresponsive by virtue of having responded successfully to a preoperative DTH challenge were eligible for entry in the study. DTH challenges were carried out at three time points in all patients: preoperatively, immediately following surgery, and on the third postoperative day (POD 3). Responses were measured 48 h after each challenge and the area of induration calculated. There were no significant differences between the laparoscopic (LC) and open (OC) colorectal resection groups in regard to demographics, indications for surgery, or type of resection carried out. The percentage of patients transfused was similar in both groups (17%, LC; 12% OC; p = NS). In the LC group, all cases were completed without conversion using minimally invasive methods. There were no perioperative deaths, and the rate of postoperative complications was similar in both groups. The preoperative and postoperative DTH results were analyzed and compared within each surgical group using several methods.

RESULTS

In regards to the OC group results, the median sum-total DTH responses for the day of surgery challenges (0.44 +/- 69 cm2) and the POD 3 challenges (0.72 +/- 3.37 cm2) were significantly smaller than the preoperative results (3.61 +/- 3.83 cm2, p <0.0005 vs op day and p <0.0003 vs POD 3 results). When the LC group results were similarly analyzed, no significant difference in DTH response was noted between the pre- and the postoperative challenge results. Additionally, when the median percent change from baseline was calculated and considered for the OC group's DTH results, both postoperative challenge time points demonstrated significantly decreased responses when compared to their preoperative results (vs day of surgery, p <0.007; vs POD 3, p <0.006). Similar analysis of the LC group's results yielded nonsignificant differences between the pre- and postoperative responses. Lastly, when the LC and the OC groups median percent change from baseline results were directly compared for each of the postoperative challenges, a significant difference was noted for the POD 0 challenge (LC, -21%; OC 88%; p <0.004) but not for the POD 3 challenge.

CONCLUSIONS

The postoperative DTH responses of the open surgery patients were significantly smaller than their preoperative responses. This was not the case for the laparoscopic group (a combination of fully laparoscopic and laparoscopic-assisted resections). When the open and laparoscopic groups results are directly compared, regarding the results of the day of surgery DTH challenges, the LC groups median percent change from baseline was significantly less than that observed in the OC group. These results imply that open colorectal resection is associated with a significant suppression of cell-mediated immune response postoperatively, whereas in this study laparoscopic colorectal resection was not. Further human studies are needed to verify these findings and to determine the clinical significance, if any, of this temporary difference in immune function following colon resection.

Combined whole tumor cell and monophosphoryl lipid A vaccine improved by encapsulation in murine colorectal cancer

BACKGROUND

Whole autologous colon cancer vaccines in combination with various adjuvants have been used in both animals and humans. At this writing, vaccine regimens have been initiated in humans 3 to 6 weeks postoperatively. This delay between tumor resection and vaccination gives surviving tumor cells an opportunity to establish themselves. Vaccine administered either preoperatively or immediately after surgery, in theory, should be more effective. However, surgery-related immunosuppression may diminish the effectiveness of pre-operative or early postoperative vaccines. This problem may be overcome by limiting postoperative immunosuppression via the use of minimally invasive methods. Alternatively, the impact of the vaccine may be improved by encapsulating the vaccine, plus adjuvant, which in theory, should extend exposure time. Encapsulation of cancer vaccines in polysaccharide particles has not yet been studied. The goal of this study was to determine whether vaccine encapsulation, preoperative vaccination, and early postoperative vaccination affected the tumor burden. In addition, laparotomy and carbon dioxide insufflation were compared.

METHODS

Vaccine was prepared from ultraviolet-irradiated C26 colon cancer cells in combination with monophosphoryl lipid A, either in suspension or entrapped in alginate beads. The C26 cell line and syngeneic BALB/c mice were used for all the studies. Tumor volumes were determined after excision of the tumors 2 weeks after inoculation in these studies.

RESULTS

Encapsulated vaccine was more effective than the standard liquid vaccine. Significantly smaller tumors were noted in mice receiving encapsulated vaccine than in either the control group (p <0.01) or the liquid vaccine group (p <0.05). The use of a preoperative encapsulated vaccine was associated with significantly smaller tumors after laparotomy, pneumoperitoneum, or anesthesia alone when the tumors were established immediately after surgery. With an already established tumor, encapsulated vaccine, when given in the early postoperative period to mice that had undergone laparotomy or anesthesia alone was associated with significantly smaller tumors that those found in control animals.

CONCLUSIONS

The incorporation of a whole-cell vaccine and monophosphoryl lipid A into alginate beads increases the efficacy of pre-operative and early postoperative tumor vaccines in the setting of both laparotomy and Carbon dioxide pneumoperitoneum. The use of perioperative vaccines may prove to be an effective way to immunize patients with cancer undergoing surgery.

Plasmodium falciparum homologue of the genes for Plasmodium vivax and Plasmodium yoelii adhesive proteins, which is transcribed but not translated

The 235-kDa family of rhoptry proteins in Plasmodium yoelii and the two reticulocyte binding proteins of P. vivax comprise a family of proteins involved in host cell selection and erythrocyte invasion. Here we described a member of the gene family found in P. falciparum (PfRH3) that is transcribed in its entirety, under stage-specific control, with correct splicing of the intron, but appears not to be translated, probably due to two reading frameshifts at the 5' end of the gene.

Thalidomide-associated hepatitis: a case report

We report a case of hepatitis in a 58-year-old woman being treated with thalidomide for end-stage plasma cell leukemia. The patient had a medical history including chronic stable hepatitis C infection. At diagnosis there was a severe anemia, thrombocytopenia, hypercalcemia, IgG paraproteinemia, peripheral blood myeloma cells, and a marrow plasmacytosis with lytic bony lesion. The disease was refractory to standard chemotherapy, and she was treated with oral thalidomide. Within 1 week she became jaundiced and developed a marked transaminitis. This promptly resolved upon cessation of thalidomide alone. Thalidomide has recently enjoyed renewed interest as a treatment in many disorders, including plasma cell leukemia. To our knowledge, this is the first reported case of thalidomide-associated hepatotoxicity. Although the mechanism of its actions on the liver are uncertain, it is possible that thalidomide acts as a direct hepatotoxin or as an immuno-modulator, altering the activity of chronic viral hepatitis. We present this case to increase awareness of a new potential side effect of thalidomide as its clinical indications expand.

Proteomic detection of PhoPQ- and acid-mediated repression of Salmonella motility

Salmonella adaptation to low pH is a critical survival response and essential for virulence. Here, we show that another key virulence-associated process, flagella-mediated cell motility, is co-regulated by low pH via the PhoPQ signal transduction system. Using a proteomic approach, we found that phase 1 and phase 2 flagellin were specifically down-regulated when acid-adapted (pH 5.0) Salmonella SL1344 cells were exposed to pH 3.0. Decreased flagellin expression and cell motility was dependent on activation of the PhoPQ pathway, which directly or indirectly negatively regulated transcription of the flagellin gene fliC. In contrast, the general stress sigma factor RpoS (sigma s) positively regulated flagellar gene expression. Low external pH had no effect on the level of H-NS protein, a further regulator of flagellar gene expression. We suggest that flagellar repression at low pH conserves ATP for survival processes and helps to limit the influx of protons into the cytosol. These results highlight the power of proteomics to reveal unanticipated links between relatively well-characterised regulatory systems in bacteria.

Motile systems in malaria merozoites: how is the red blood cell invaded?

The ability of the malaria parasite to invade erythrocytes is central to the disease process, but is not thoroughly understood. In particular, little attention has been paid to the motor systems driving invasion. Here, Jennifer Pinder, Ruth Fowler and colleagues review motility in the merozoite. The components of an actomyosin motor are present, including a novel unconventional class XIV myosin, now called Pfmyo-A, which, because of its time of synthesis and location, is likely to generate the force required for invasion. In addition, there is a subpellicular microtubule assemblage in falciparum merozoites, the f-MAST, the integrity of which is necessary for invasion.

Use of the stationary phase inducible promoters, spv and dps, to drive heterologous antigen expression in Salmonella vaccine strains

We have investigated the ability of the growth phase regulated promoters dps and spv, to drive expression of heterologous antigens in Salmonella vaccine strains. Reporter plasmids were constructed which directed beta-galactosidase expression from dps (pDpslacZ) or spv (pSpvlacZ) and these were introduced independently into the Salmonella typhimurium vaccine strain SL3261 (aroA(-)). beta-galactosidase expression was induced 20-fold and 100-fold when broth cultures of SL3261 (pDpslacZ) or SL3261 (pSpvlacZ) respectively, entered the stationary phase of growth. Within macrophages, beta-galactosidase expression was induced 3.5-fold with SL3261 (pDpslacZ) and 7-fold with SL3261 (pSpvlacZ). The spv and dps promoters were used to drive independent expression of the C fragment domain of tetanus toxin (TetC) from plasmids harboured in S. typhimurium SL3261. Levels of anti-TetC antibodies were significantly higher in the sera of BALB/c mice perorally inoculated with SL3261 (pSpvtetC) or SL3261 (pDpstetC) compared to unvaccinated controls. This suggests that these promoter systems may be used to drive foreign antigen expression in live oral Salmonella vaccines.

Igh-6(-/-) (B-cell-deficient) mice fail to mount solid acquired resistance to oral challenge with virulent Salmonella enterica serovar typhimurium and show impaired Th1 T-cell responses to Salmonella antigens

In the present study we evaluated the role of B cells in acquired immunity to Salmonella infection by using gene-targeted B-cell-deficient innately susceptible mice on a C57BL/6 background (Igh-6(-/-)). Igh-6(-/-) mice immunized with a live, attenuated aroA Salmonella enterica serovar Typhimurium vaccine strain showed impaired long-term acquired resistance against the virulent serovar Typhimurium strain C5. Igh-6(-/-) mice were able to control a primary infection and to clear the inoculum from the reticuloendothelial system. However, Igh-6(-/-) mice, unlike Igh-6(+/+) C57BL/6 controls, did not survive an oral challenge with strain C5 at 4 months after vaccination. Transfer of immune serum did not restore resistance in Igh-6(-/-) mice. Total splenocytes and purified CD4(+) T cells obtained from Igh-6(-/-) mice 4 months after vaccination showed reduced ability to release Th1-type cytokines (interleukin 2 and gamma interferon) upon in vitro restimulation with serovar Typhimurium soluble cell extracts compared to cells obtained from Igh-6(+/+) C57BL/6 control mice. Therefore, the impaired resistance to oral challenge with virulent serovar Typhimurium observed in B-cell-deficient mice, which cannot be restored by passive transfer of Salmonella-immune serum, may be in part due to a reduced serovar Typhimurium-specific T-cell response following primary immunization.