Is there an Ethnic Predisposition to Developing Brain Metastases (BM) in Asian Patients with Colorectal Cancer?

BACKGROUND

Most common sites of metastases in patients with colorectal cancer (CRC) include liver and lung. Brain metastases are very rare but their presence is associated with a poor prognosis and shorter survival. We report our investigation into the impact of race/ethnicity on the incidence of BM in CRC patients.

METHOD

We retrospectively reviewed patients diagnosed with CRC from 2010 - 2018 at a single institution and analyzed any association of development of brain metastases with race and ethnicity. Race and ethnicity were defined in accordance with federal standards set by the US Census.

RESULT

We identified 264 CRC patients and 76(29%) were identified as Asian. Of those 76 patients, 5(7%) developed brain metastases. All 5 patients were male and stage IV at initial diagnosis. Brain metastases was a late stage phenomenon. Median time to development of brain metastases was 29 months (Range: 26 - 33). Median overall survival after BM diagnosis was 5.5 months (Range: 4 - 11). Overall survival was longest for the patient who had both radiation and surgery.

CONCLUSION

Our study showed an incidence of brain metastases of 7% in the Asian sub-population compared to the historical control of 0.6% - 3.2% in the overall population. These results at the least warrant further investigation in a larger patient population of brain metastases in CRC patients with emphasis on molecular markers.

Is There any Survival Benefit of Maintenance Chemotherapy Following Adjuvant Chemotherapy in Patients with Resected Pancreatic Cancer Patients with Post-Surgery Elevated CA 19-9?

BACKGROUND

Pancreatectomy offers only potential for cure but is only possible in a minority of patients. Even in those patients who receive adjuvant chemotherapy, majority of them succumb to death due to metastases. Radiation Therapy Oncology Group 9704 showed that post-surgery CA 19-9 levels are an important predictor of survival. European study group for pancreatic cancer-3 showed that completion of all 6 cycles of adjuvant chemotherapy was an independent prognostic factor. Any survival benefit of an intensified chemotherapy strategy has not been demonstrated in patients with persistently elevated CA 19-9 following surgery. The object of this study was to investigate any benefit of maintenance chemotherapy following adjuvant in these patients.

METHODS

Twenty patients with R0 surgery of pancreatic cancer who received adjuvant chemotherapy with post-surgery elevated CA 19-9 but no radiographic evidence of cancer was identified from 2005-2017. Either biopsy or positron emission tomography scan determined recurrence of cancer. Efficacy endpoints including overall survival and disease-free survival were assessed.

RESULTS

Maintenance and additional chemotherapeutic agents included 5-FU, capecitabine, platinum agents, irinotecan and nab-paclitaxel. CA 19-9 normalized in 3 patients while 22 persisted to be elevated or had further increase in the marker. Two patients underwent metastatectomy. Median disease-free survival was 14.5m (9-18), OS 29m (19-96) and OS rates were 80%, 50% at 1 and 2 years respectively.

CONCLUSIONS

We believe that the longer overall survival of our patients with elevated CA 19-9 post-surgery was due to maintenance and additional chemotherapy following planned 6-months of adjuvant therapy, close monitoring with monthly CA 19-9 and 3-monthly computed tomography scans. Our study also underlines importance of collecting pre-surgery CA 19-9 and complete staging including chest. Prospective study aiming to evaluate role of maintenance or intensified chemotherapy or targeted agents are indicated.

Safety and efficacy of biweekly gemcitabine in combination with capecitabine (GemCap) in elderly and frail patients (pts) with resected pancreatic cancer (PC)

4628

Background: ESPAC-4 study showed that GemCap conferred a survival benefit over gemcitabine monotherapy in resected PC patients. ESPAC-4 included patients with median age of 65 years (37-81) and ECOG performance status (PS) of 0 (43%), 1 (54%) and 2 (2%) who received a median cumulative dose of gemcitabine of 15,000 mg/m2, capecitabine. Here we present our experience with an adopted biweekly regimen of GemCap in patients who were ≥ 75 years and those who were deemed not suitable for ESPAC-4 regimen. Methods: Patients ≥ 75 years with resected PC, ECOG PS of 0-2 and no prior treatments were included. Patients were treated with a modified regimen of gemcitabine (1000-2000 mg/m2) every 2 weeks and capecitabine (800-1000 mg/m2) day 1-7 every 2 weeks. Patients were evaluated for progression-free survival (PFS), overall survival (OS) and sites of recurrence. Toxicities were graded according to NCI CTCAE v5.0. Results: Thirty-five (22M, 13F) patients, ≥ 75 (median age 79) treated with biweekly Gem-Cap adjuvant treatment. 7 (28%) patients had ECOG PS of 1 and 28 (72%) had ECOG PS of 2. There were 5, 7 and 16 patients with stage I, II and III disease. Nine patients (25%) had R1 and 26 (75%) had R0 resection. The median PFS and OS were 8.0 months and 22.0 months. Nine (25%) had local recurrence, 21 (60%) had metastatic disease and 3 (8.6%) had NED. Two patients were lost to follow-up. The most frequent toxicities were grades 1-2 anemia (20%), thrombocytopenia (8%) and hand-foot syndrome (HFS) (10%). Grade ≥3 included diarrhea (4%) and HFS (1%) with no treatment-related discontinuations. Treatment compliance was 100%. Delays were necessary in 7% of cases and dose reduction was required in 4% of cases. There was no treatment related death. Conclusions: This schedule of biweekly GemCap regimen suggests an acceptable option in for elderly, frail patients with PC and warrants further exploration in patients not suitable for FOLFIRINOX, full dose GemCap or a clinical trial. This regimen required fewer dose reduction, omission or delays and allowed to administer pegylated-filgrastim. Previous studies have also shown decreased toxicity and equal efficacy of 7/7 schedule of capecitabine. Moreover, fewer visits to oncology and related expense do favor towards benefit. Additionally, this tolerable regimen is ideal to be combined with immunotherapy in clinical trials for this patient population.

A prospective pilot study of pharmacogenetic-based dosing of 5-fluouracil (5-FU) and irinotecan (IRI) in patients (pts) with gastrointestinal (GI) malignancies

e16138

Background: 5-FU and IRI are core components of chemotherapies for GI malignancies. Previous studies have shown that mutations in DPYP and TYMS predispose the pts to 5-FU toxicities. Mutations in UGT1A1 predispose pts to increased IRI toxicities. Retrospective data suggest that these mutations may have implications in selecting dosage and/or schedule of 5-FU and IRI. We present here a prospective study of upfront pharmacogenetic testing with tailored dose of respective drugs in pts with these mutations. Methods: Pts with GI malignancies were tested for DPYD, TYMS and UGT1A1 mutations before initiating 5-FU and/or IRI. Mutation analyses were performed at Quest Diagnostics Nichols Institute. Pts were dosed at 50% if DPYD was abnormal and 25% dose reduction if indicated by TYMS or UGT1A1 * 28 (homozygous) abnormality. Adverse events (AEs) were graded according to CTCAE v.5.0. We compared AEs to our previously collected data in DPYD, TYMS deficient pts who underwent genetic testing due to toxicity to 5-FU. Results: Of 226 pts screened, 5 pts had DPYP mutations with genotypes (3: c.1905+1G/A; 1: c.2846A/T; 1: c.557A/G). TYMS mutations were identified in 24 pts. For 3'-UTR, distributions were: intermediate expression genotype 4: INS/DEL, low expression genotype 5: DEL/DEL. For 5'TSER, distributions were: low expression genotypes (6:2R/2R; 3:2R/3RC; 4: 3RC/3RC) and high expression genotypes (2: 2R/3RG, 2: 3RG/3RC, 1: 3RG/3RG). UGT1A1*28 mutation was identified in 53 pts – 19 homozygous and 34 heterozygous. No grade ≥3 neutropenia was observed with reduced dose of IRI in UGT1A 1 variant pts compared to 33% reported in pts not tested. For TYMS and DPYD variants, no grade ≥3 AEs were seen. Comparison of AEs in pts with post treatment genetic testing is listed in Table. Conclusions: Pharmacogenetic based dosing of 5-FU and IRI led to less frequent, less severe toxicities and no death related to AEs was observed in our pts. This can improve pts’ quality of life and lessen economic burden of managing severe AEs. Currently, there are no formal guidelines regarding testing for DPYD, TYMS and UGT1A1. Although non-randomized, this study advocates for systemic screening of pharmacogenetic testing in pts with GI malignancies. [Table: see text]

Chronic Use of Long-Acting Somatostatin Analogues (SSAs) and Exocrine Pancreatic Insufficiency (EPI) in Patients with Gastroenteropancreatic Neuroendocrine Tumors (GEP-NETs): An Under-recognized Adverse Effect

BACKGROUND

Somatostatin Analogues (SSAs) are used to treat Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) and acromegaly. Side effects of SAAs usually include biliary disorders, gastrointestinal disorders, injection-site pain and hyperglycemia. Exocrine Pancreatic Insufficiency (EPI) is often misdiagnosed as disease progression or failure to SAAs or diagnosed after a delay in patients receiving SAAs. We present our experience with EPI developing in patients following use of SAAs.

METHODS

We reviewed chart and pharmacy records of 110 GEP-NETs patients who received SSAs. Data was collected including demographics, pathology, stage, dose/duration of long and short-acting SA, use of antidiarrheal, pancreatic enzyme replacement (PER), proton pump inhibitors (PPI) or H2 blockers). Laboratory data include chromogranin-A (CgA), urine 5-HIAA and quantitative fecal fat test (QFFT) or fecal elastase test (FE). EPI was defined by a FE below normal level OR by a reduction of ≥ 21.2% or steatorrhea on QFFT. Patients who were identified to develop EPI were treated with pancreatic exocrine replacement therapy (PERT).

RESULTS

Among, 110 GEP-NETs patients, 104 received LA Octreotide and 6 Somatuline Depot Injection. Of these, 23 received short-acting SSA for worsening diarrhea, 96 had intensification of antidiarrheal and 1 got telotristat ethyl. QFFT confirmed EPI in 19, 11 based on clinical symptoms, and 16 had sample error or refusal to collect specimen. CTCAE 4.0 grades of EPI were: grade 2(69%), grade 3(22%) and grade 4(9%). Median time to development of EPI was 12 months (95%CI 3 - 23). Except 1, all patients received PERT either with concomitant PPI (13) or later if no improvement with PERT (6) and 2 on H2 blockers. 37% of the patients had improvement in EPI within 4-8 weeks. Deficiency of vitamins and trace elements was found in 11 of 19 patients, who received supplementation.

CONCLUSIONS

Our experience constitutes the first and the largest study addressing EPI as a rare but serious complication of chronic use of SAAs. Although SAAs are used to treat diarrhea, paradoxically they can worsen diarrhea secondary to EPI. Early recognition and diagnosis of this under-diagnosed and under-reported side effect of SAAs, such as EPI, can improve not only diarrhea and weight loss in these patients but also can reduce cost of using short-acting SAAs and antidiarrheal.

Investigation of an ethnic predisposition to developing brain metastases (BM) in Asian patients with colorectal cancer (CRC)

e15023

Background: CRC, the third most common cancer in the United States, carries racial/ethnic disparities in both incidence and mortality. With availability of effective systemic therapies, the life of CRC patients can be prolonged which thereby increases the risk of metastases at uncommon sites, such as the brain. We report our investigation into the impact of race/ethnicity on the incidence of BM in CRC patients using retrospective data (2010 – 2018) at a single institution. Methods: We retrospectively reviewed patients diagnosed with CRC and collected data on age, race/ethnicity, stage, treatment modalities, metastatic sites, and survival. Race and ethnicity were defined in accordance with federal standards set by the U.S. Census. Following this, race/ethnicity was self-declared and/or based on the primary language declared and categorized as non-Hispanic White, Hispanic White, non–Hispanic Black, Asian, or Unknown/Other. CRC location was classified as right-sided, left-sided or rectal. Results: We identified 264 CRC patients (median age: 61; range: 38 - 99). Among them 123 identified as non-Hispanic white, 28 non-Hispanic black, 26 Hispanic white, and 9 declared Other. There were 76 (29%) who identified as Asian. Of those 76 patients, 5 (7%) developed BM. All 5 patients were male and stage IV at initial diagnosis. BM was a late stage phenomenon with rectal primary and lung metastases seemly associated with an increased risk in the specific cohort. Molecular markers such as KRAS were available in 3 patients without clear association. Median time to development of BM was 29 months (range: 26 - 33). Median overall survival after BM diagnosis was 5.5 months (range: 4 - 11). Overall survival was longest for the patient who had both radiation and surgery. Conclusions: Our study showed an incidence of BM of 7% in the Asian sub-population compared to the historical control of 0.6 – 3.2% in the overall population. These results at the least warrant further investigation in a larger patient population of BM in CRC patients with emphasis on molecular markers. Recognition of BM in CRC patients is clinically relevant secondary to multiple lines of therapy as mentioned earlier and its grave impact on outcome.

Racial Differences in Accepting Pegfilgrastim Onpro Kit (On-Body Injector) Use Among Cancer Patients

Background

1.1.Neulasta Onpro kit eliminates need for additional clinic visit after chemotherapy. Given the racially diverse population in our institution, we investigated acceptance of Onpro kit among patients on chemotherapy.

Research Design and Methods

1.2.Single-institution, retrospective review conducted in patients with GI tumors who received Onpro kit within 1 hour of completion of systemic chemotherapy from Jan 2014 through Jan 2018. Clinic/nursing notes and pharmacy records were reviewed to identify patients who refused Onpro kit and to discern reasons for refusal, including racial reason.

Results

1.3.Total 238 orders for kit were voided amongst 68 patients (Caucasian 41; African American 7; Spanish 3; Asian 17). Overall, 15/68 patients refused kit (22%) of these 87% were Asian. The reasons for refusal included dislike of bulky attachment to skin, request to place kit on stomach instead of arm, trepidation over unwitnessed administration of drug, fear of reaction, disposal at home, fear of pain, lack of confirmation of proper dose administration, and need for MRI.

Conclusions

1.4.While Onpro kit is an attractive alternative, 22% of patients with voided orders, mainly of Asian race, declined its application. We believe the current study represents the first look at important racial differences in accepting Onpro kit. Consideration of patients' cultural heritage, race, ethnicity and education may facilitate communication between physicians and patients to achieve optimal cancer care.

Treatment with Lanreotide Depot Following Octreotide Long-Acting Release Among Patients with Gastroenteropancreatic Neuroendocrine Tumors

Objective: To examine patients with metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NETs) who receive sequential treatment with somatostatin analogs. Materials and Methods: This retrospective chart review examined lanreotide depot/autogel tolerability and efficacy among GEP-NET patients who received lanreotide after octreotide long-acting release (LAR) at Tufts University Medical Center. Information obtained included background patient characteristics, dosing, adverse events (AEs), radiologic response, and biochemical markers. Results: Patients (n = 16; 43-81 years; mean age, 64.25 years; 11 female) with nonfunctional, low-grade GEP-NETs receiving octreotide LAR 30-60 mg were transitioned to lanreotide because of patient decision (n = 6), disease progression (n = 6), AEs (n = 2), poor tolerance (n = 1), and injection discomfort/pain (n = 1). Lanreotide doses started at 120 mg (n = 13), 90 mg (n = 1), or 60 mg (n = 2); 8 patients received concomitant therapies, mostly liver-directed (radiofrequency ablation/radioembolization). AEs associated with lanreotide experienced by ≥2 patients were fatigue, diarrhea, nausea, hypertension, pancreatic enzyme deficiency, and hyperglycemia. Radiologic treatment responses of the combination of lanreotide with other therapeutic modalities included complete response (n = 1), partial response (n = 5), and stable disease (n = 9). One patient had radiologic progression. Serum serotonin and chromogranin levels decreased, but urinary 5-hydroxyindoleacetic acid levels appeared relatively unchanged. Conclusion: Among post-octreotide GEP-NET patients, including those with disease progression or poor octreotide tolerance, lanreotide alone or with concomitant therapies was well tolerated and associated with radiologic responses.

Pancreatic exocrine insufficiency (PI) secondary to chronic use of long-acting (LA) somatostatin analogues (SA) in patients (pts) with gastroenteropancreatic neuroendocrine tumors (GEP-NETs)

454

Background: SA are used in GEP-NETs and acromegaly. Side effects of SAs include biliary disorders, gastrointestinal disorders, injection-site pain and hyperglycemia. PI is often misdiagnosed as disease progression or failure to SA or diagnosed after a delay in pts receiving SA. We present our experience with PI developing in pts following chronic use of SA. Methods: Retrospective chart and pharmacy review of GEP-NETs pts (6/2009 - 6/2017) was completed. Data including demographics, dose/duration of long and short-acting SA, antidiarrheal, pancreatic enzyme replacement (PER), proton pump inhibitors (PPI), chromogranin A (CgA), urine 5-HIAA and quantitative fecal fat test (QFFT) was collected. Results: 110 GEP-NETs pts (Med. age: 56 yr) were identified. 104 pts received LA Octreotide acetate and 6 Somatuline Depot Injection. Of these, 23 received SA octreotide for worsening diarrhea, 96 had intensification of antidiarrheal and 1 got telotristat ethyl. 79 pts were evaluated by nutritionist and/or gastroenterology. QFFT was performed in 47 pts with worsening diarrhea despite stable or improved CgA/urine 5-HIAA. 19 had evidence of steattorrhea and received PER at a dose of 72,000 lipase units per meal. 13 received PPI concomitantly while 6 started when symptoms did not improve with PER. In addition, low fat diet was recommended. 14 of 19 had improvement in diarrhea within 4-8 weeks. 2 pts were non-compliant and 3 were found to have motility disorders. Deficiency of vitamins and trace elements was found in 11 of 19 pts, who received supplementation. Conclusions: Our experience constitutes first study addressing PI as a rare but serious complication of chronic use of SA. Although SA are used to treat diarrhea, paradoxically they can worsen diarrhea secondary to PI. It is believed that SA may inhibit secretion and release of hormones (amylase, trypsin, lipase, secretin, CCK, motilin, bile acid) leading to PI. Early recognition and diagnosis of this under-diagnosed and under-reported side effect of SA can improve not only diarrhea and weight in these pts but also can reduce cost of using short-acting SA and antidiarrheal.

Is there any survival benefit of additional chemotherapy (C) following adjuvant C in pancreatic cancer (PC) patients (pts) with postsurgery elevated CA19-9?

491

Background: Pancreatectomy offers only potential for cure but is only possible in a minority of pts. Even in those pts who receive adjuvant C, majority of them succumb to death due to metastases. RTOG 9704 showed that post-surgery CA 19-9 levels are an important predictor of survival. ESPAC-3 showed that completion of all 6 cycles of adjuvant C was an independent prognostic factor. Any survival benefit of an intensified C strategy has not been demonstrated in pts with persistently ↑ CA19-9. The object of this study was to investigate any benefit of additional C following adjuvant in these pts. Methods: 25 pts with R0 surgery of PC who received adjuvant C with post-surgery ↑ CA 19-9 but no radiographic evidence of cancer were identified between 2005-2017. Either biopsy or PET scan determined recurrence of PC. Efficacy endpoints were overall survival (OS) and disease-free survival (DFS). Results: The Table summarizes results. Additional C included 5-FU, capecitabine, platins, irinotecan and nab-paclitaxel. CA 19-9 normalized in 3 pts while 22 remained ↑ or further ↑. Two pts underwent metastatectomy. Median DFS was 14.5m (9-18), OS 29m (19-96) and OS rates were 80 %, 50 % at 1 and 2 years respectively. Conclusions: We believe that the longer OS of our pts with ↑ CA 19-9 post-surgery was due to additional C following adjuvant C, close monitoring with monthly CA19-9 and 3-monthly CT scans. Our study also underlines importance of collecting pre-surgery CA19-9 and complete staging including chest. Prospective study aiming to evaluate role of maintenance or intensified C are indicated.[Table: see text]

Can patients with eating disorders learn to eat intuitively? A 2-year pilot study

The present article reports on a 2-year pilot study that evaluated the effectiveness of an intuitive eating program for patients in an eating disorder treatment center. Standardized measures of intuitive eating and eating disorder and psychological symptoms were administered. Psychotherapists and dietitians rated patients on the healthiness of their eating attitudes and behaviors. Preliminary findings indicated that patients can develop the skills of intuitive eating, and that the ability to eat intuitively is associated with positive treatment outcomes for each diagnostic category (i.e., anorexia nervosa, bulimia nervosa, and eating disorder not otherwise specified). We conclude by offering recommendations about how to implement intuitive eating training safely and effectively in inpatient and residential treatment programs.

Genetic diversity in natural populations of a soil bacterium across a landscape gradient

Genetic diversity in natural populations of the bacterium Pseudomonas cepacia was surveyed in 10 enzymes from 70 clones isolated along a landscape gradient. Estimates of genetic diversity, ranging from 0.54 to 0.70, were higher than any previously reported values of which we are aware and were positively correlated with habitat variability. Patterns of bacterial genetic diversity were correlated with habitat variability. Findings indicate that the source of strains used in genetic engineering will greatly affect the outcome of planned releases in variable environments. Selection of generalist strains may confer a large advantage to engineered populations, while selection of laboratory strains may result in quick elimination of the engineered strains.

Integrating biomass, sulphate and sea-salt aerosol responses into a microphysical chemical parcel model: implications for climate studies

Aerosols are known to influence significantly the radiative budget of the Earth. Although the direct effect (whereby aerosols scatter and absorb solar and thermal infrared radiation) has a large perturbing influence on the radiation budget, the indirect effect (whereby aerosols modify the microphysical and hence the radiative properties and amounts of clouds) poses a greater challenge to climate modellers. This is because aerosols undergo chemical and physical changes while in the atmosphere, notably within clouds, and are removed largely by precipitation. The way in which aerosols are processed by clouds depends on the type, abundance and the mixing state of the aerosols concerned. A parametrization with sulphate and sea-salt aerosol has been successfully integrated within the Hadley Centre general circulation model (GCM). The results of this combined parametrization indicate a significantly reduced role, compared with previous estimates, for sulphate aerosol in cloud droplet nucleation and, consequently, in indirect radiative forcing. However, in this bicomponent system, the cloud droplet number concentration, N(d) (a crucial parameter that is used in GCMs for radiative transfer calculations), is a smoothly varying function of the sulphate aerosol loading. Apart from sea-salt and sulphate aerosol particles, biomass aerosol particles are also present widely in the troposphere. We find that biomass smoke can significantly perturb the activation and growth of both sulphate and sea-salt particles. For a fixed salt loading, N(d) increases linearly with modest increases in sulphate and smoke masses, but significant nonlinearities are observed at higher non-sea-salt mass loadings. This non-intuitive N(d) variation poses a fresh challenge to climate modellers.

Computed tomography-based tissue-engineered scaffolds in craniomaxillofacial surgery

INTRODUCTION

Tissue engineering provides an alternative modality allowing for decreased morbidity of donor site grafting and decreased rejection of less compatible alloplastic tissues.

METHODS

Using image-based design and computer software, a precisely sized and shaped scaffold for osseous tissue regeneration can be created via selective laser sintering. Polycaprolactone has been used to create a condylar ramus unit (CRU) scaffold for application in temporomandibular joint reconstruction in a Yucatan minipig animal model. Following sacrifice, micro-computed tomography and histology was used to demonstrate the efficacy of this particular scaffold design.

RESULTS

A proof-of-concept surgery has demonstrated cartilaginous tissue regeneration along the articulating surface with exuberant osseous tissue formation. Bone volumes and tissue mineral density at both the 1 and 3 month time points demonstrated significant new bone growth interior and exterior to the scaffold.

CONCLUSION

Computationally designed scaffolds can support masticatory function in a large animal model as well as both osseous and cartilage regeneration. Our group is continuing to evaluate multiple implant designs in both young and mature Yucatan minipig animals.

Rapid population divergence in thermal reaction norms for an invading species: breaking the temperature-size rule

The temperature-size rule is a common pattern of phenotypic plasticity in which higher temperature during development results in a smaller adult body size (i.e. a thermal reaction norm with negative slope). Examples and exceptions to the rule are known in multiple groups of organisms, but rapid population differentiation in the temperature-size rule has not been explored. Here we examine the genetic and parental contributions to population differentiation in thermal reaction norms for size, development time and survival in the Cabbage White Butterfly Pieris rapae, for two geographical populations that have likely diverged within the past 150 years. We used split-sibship experiments with two temperature treatments (warm and cool) for P. rapae from Chapel Hill, NC, and from Seattle, WA. Mixed-effect model analyses demonstrate significant genetic differences between NC and WA populations for adult size and for thermal reaction norms for size. Mean adult mass was 12-24% greater in NC than in WA populations for both temperature treatments; mean size was unaffected or decreased with temperature (the temperature-size rule) for the WA population, but size increased with temperature for the NC population. Our study shows that the temperature-size rule and related thermal reaction norms can evolve rapidly within species in natural field conditions. Rapid evolutionary divergence argues against the existence of a simple, general mechanistic constraint as the underlying cause of the temperature-size rule.

Computed tomography-based tissue-engineered scaffolds in craniomaxillofacial surgery

INTRODUCTION

Tissue engineering provides an alternative modality allowing for decreased morbidity of donor site grafting and decreased rejection of less compatible alloplastic tissues.

METHODS

Using image-based design and computer software, a precisely sized and shaped scaffold for osseous tissue regeneration can be created via selective laser sintering. Polycaprolactone has been used to create a condylar ramus unit (CRU) scaffold for application in temporomandibular joint reconstruction in a Yucatan minipig animal model. Following sacrifice, micro-computed tomography and histology was used to demonstrate the efficacy of this particular scaffold design.

RESULTS

A proof-of-concept surgery has demonstrated cartilaginous tissue regeneration along the articulating surface with exuberant osseous tissue formation. Bone volumes and tissue mineral density at both the 1 and 3 month time points demonstrated significant new bone growth interior and exterior to the scaffold.

CONCLUSION

Computationally designed scaffolds can support masticatory function in a large animal model as well as both osseous and cartilage regeneration. Our group is continuing to evaluate multiple implant designs in both young and mature Yucatan minipig animals.

Examining the relationship between religious orientation and eating disturbances

The relationship between religion and eating concerns is receiving increasing empirical attention. The current investigation sought to examine the relationship between eating attitudes and religious orientation, utilizing the fourfold typology of religious orientation. A curvilinear relationship was found between religious orientation and eating attitudes among a subclinical college population and a clinical population of individuals receiving inpatient treatment for eating disorders, particularly among extrinsically orientated individuals with diagnosis of bulimia nervosa.

Antigen presentation of a modified tumor-derived peptide by tumor infiltrating lymphocytes

CD8+ T-lymphocytes recognize peptides in the context of major histocompatibility complex (MHC) class I antigens. Upon activation, these cells differentiate into effector cytotoxic T lymphocytes (CTL) and no longer require formal antigen presentation by professional antigen presenting cells (APC). Subsequently, any cell expressing MHC class I/cognate peptide can stimulate CTL. Using TIL specific for a melanoma antigen-derived peptide, IMDQVPFSV (g209 2M), we sought to determine whether these CTL could present peptide to each other. Our findings demonstrate that peptide presentation of the g209 2M peptide epitope by TIL is comparable to conventional methods of using T2 cells as APC. We report here that CTL are capable of self-presentation of antigenic peptide to neighboring CTL resulting in IFN-gamma secretion, proliferation, and lysis of peptide-loaded CTL. These results demonstrate that human TIL possess both APC functions as well as cytotoxic functions and that this phenomenon could influence CTL activity elicited by immunotherapy.

Measurement of the complex refractive index of isotropic materials with mueller matrix polarimetry

The complex refractive index of materials at infrared wavelengths is often determined when absorption measurements are made at selected wavelengths, and then the Kramers-Kronig relationship is used to calculate the real part of the index. Because many organic materials are highly absorbing in the infrared, absorption measurements require a short path length. We report on the use of an attenuated total internal reflection (TIR) method in combination with an infrared Mueller matrix spectropolarimeter to measure the Mueller matrix spectrum of samples from 3 to 14 mum. From the elements of the Mueller matrix the complex refractive index is determined for materials whose TIR interfaces are eigenstates of s and p polarization. The calculated index for water compares well with data found in the literature.

Application of a topical immune response modifier, resiquimod gel, to modify the recurrence rate of recurrent genital herpes: a pilot study

Resiquimod (R-848), a topically active immune response modifier, induced production of interferon-alpha and interleukin-12 in cultured blood mononuclear cells and decreased genital herpes recurrences in an animal model. In this study, 52 patients with frequently recurrent genital herpes applied topical resiquimod gel 0.01% (twice or thrice weekly) or 0.05% (once or twice weekly) or vehicle gel to herpes lesions for 3 weeks. During the 6-month observation period after treatment, median days to first recurrence in the pooled resiquimod group was 169 days, compared with 57 days for the vehicle group (P=.0058). In all, 32% of resiquimod-treated patients completed the observation period without a recurrence, compared with 6% of vehicle-treated patients (P=.039). Resiquimod 0.05% twice weekly produced dose-limiting inflammation at the lesion sites, but the other regimens were well tolerated. Application of resiquimod to genital herpes lesions appeared to reduce the frequency of recurrences.

Radiocesium in fish from the Savannah River and Steel Creek: potential food chain exposure to the public

This study examined radiocesium (137Cs) levels in fish from the vicinity of the Department of Energy's Savannah River Site (SRS), a former nuclear weapons production facility in South Carolina. Fish from the Savannah River were sampled above (upstream), along, and below (downstream) the SRS, and from Steel Creek, a tributary that runs through the SRS. There was some off-site contamination of 137Cs in the Savannah River watershed due to low-level releases from past nuclear production on the SRS. The null hypotheses tested were that there would be no differences in 137Cs levels as a function of location along the river, and between species collected from the river and from Steel Creek on the SRS. For six of eight species of fish collected from the Savannah River, there were no differences in 137Cs levels in muscle from fish collected above, along, or below the SRS; exceptions were bowfin and shellcracker. Fish collected from Steel Creek had significantly higher levels (by about an order of magnitude) of 137Cs in muscle tissue than fish collected in the Savannah River. However, no fish from either Steel Creek or the Savannah River had 137Cs levels above the European Economic Community limit for fresh meat of 0.6 Bq/g. Lifetime cancer risk was calculated using the cancer slope factor of 3.2 x 10(-11)/pCi, and various fish consumption scenarios reflecting actual data from Savannah River fishermen. Using mean 137Cs concentrations and median fish consumption for 70 years for Black males-the group with the highest consumption-the excess lifetime risk associated with the eight species of fish in the Savannah River ranged from 9.0 x 10(-7) to 1.0 x 10(-5). The same calculation for fish from Steel Creek gave risk estimates from 1.4 to 8.0 x 10(-5). The 95% level for consumption by Blacks, however, was about 70 kg/year. Black fishermen consuming that amount of bass from Steel Creek would sustain a lifetime risk of 3.1 x 10(-4), whereas the same consumption of Savannah River bass would yield a risk estimate of 1.5 x 10(-5).

Nature of the liquid crystalline phase transitions in the cesium pentadecafluorooctanoate (CsPFO)-water system: the nematic-to-isotropic transition

Deuterium NMR spectroscopy of 2H2O has been used to monitor the magnetic-field-induced order on approaching a transition to a nematic phase in isotropic solutions of disklike micelles of cesium pentadecafluorooctanoate. Highly accurate data on the phase boundaries and spinodals have been obtained for solutions with volume fraction concentration straight phi between 0.078 and 0.201. The quantity TIN-T*, where T* is the spinodal limit of the isotropic phase and TIN is the temperature at which the nematic phase first appears on cooling, decreases linearly with decreasing concentration, extrapolating to zero only at zero concentration. Thus, there is no evidence to support the presence of a Landau point along the transition line as has previously been conjectured. The values for (TIN-T*)/TIN are in the range 10(-5)-10(-4), up to two orders of magnitude smaller than corresponding values reported for calamitic thermotropic nematics. The transition gap (phiNI-phiIN)/phiIN approximately 0.33% for phi<0.20 is also very small, although finite as required for a first-order phase transition. These data, when combined with previously measured properties, present an intriguing picture of the isotropic-to-nematic phase transition in a paradigmatic system of self-assembled diskotic particles. However, it is not completely clear, within the context of current theoretical understanding, whether the behavior of this system is explicable by hard-particle models, or if the self-assembly plays a crucial role in weakening the phase transition.

The cel4 gene of Agaricus bisporus encodes a beta-mannanase

Mannases have industrial uses in food and pulp industries, and their regulation may influence development of the mushrooms of commercially important basidiomycetes. We expressed an Agaricus bisporus cel4 cDNA, which encodes a mannanase, in Saccharomyces cerevisiae and Pichia pastoris. CEL4 had no detectable activity on cellulose or xylan. This gene is the first isolated from this economically important fungus to encode a mannanase. P. pastoris secreted about three times more CEL4 than S. cerevisiae. The removal of the cellulose-binding domain of CEL4 lowered the secreted specific activity by P. pastoris by approximately 97%. The genomic sequence of cel4 was isolated by screening a cosmid library of A. bisporus C54-carb8. The open reading frame was interrupted by 12 introns. The level of extracellular CEL4 increases dramatically at the postharvest stage in compost extracts of A. bisporus fruiting cultures. In laboratory liquid cultures of A. bisporus, the activity of CEL4 detected in the culture filtrate reached a maximum after 21 days. The levels of CEL4 broadly mirrored the levels of enzyme activity. In the Solka floc-bound mycelium, CEL4 protein showed a maximum after 2 to 3 weeks of culture and then declined. Changes in CEL4 activity during fruiting-body development suggest that hemicellulose utilization plays an important role in sporophore formation. The availability of the cloned gene will further studies of compost decomposition and the extracellular enzymes that fungi deploy in this process.

Ability, disability, and the oldest old

A measure of range of ability is used to profile the 85-years-old-and-older (oldest old) population, including the highly disabled institutional population. This new measure uses two new questions available in the 1990 Decennial Census concerning a self-care limitation and a mobility limitation as well as the usual question concerning a work limitation. In addition to examining the extent of disability among the oldest old, the article examines the extent of care potentially available in the household as well as the economic characteristics of this age group. It is also profiled in terms of relevant personal characteristics, including age, gender, marital status, race, ethnicity, rural residence, education, and employment. A key question addressed is the need for help or care among the oldest old and how various long-term care proposals would meet such needs. A careful analysis of this unique and growing population is necessary to both allay fears of the cost of care or help as well as to dispel stereotypes of this age group as frail and dependent, and in need of institutional care.

Rural and urban differences in mortality among Americans 55 years and older: analysis of the National Longitudinal Mortality Study

Previous research on rural and urban differences in risk of mortality has been inconclusive. This article used data from the National Longitudinal Mortality Study to establish whether all-cause mortality risk among persons 55 years and older varies by degree of urbanization, controlling for the potential sociodemographic confounders of age, gender, race/ethnicity, education, income, and marital status. Using the Cox Proportional Hazards Regression Procedure, the authors found that persons living in the most rural locales and those living in rural communities in standard metropolitan statistical areas (SMSAs) have the lowest risk of mortality, while those living in SMSA central cities had the highest risk of dying during the study period. The protective effect of rural residence declines in older age cohorts.

Women, marital status, and symptoms of depression in a midlife national sample

Previous studies of the correlates of depression among women have not generally been based on adequate midlife samples or precision in the specification of marital status categories. The present analysis is designed to address these deficiencies and is based on data from the Health and Retirement Survey-Wave 1 (i.e., respondents 51 to 61 years old). Results indicate that married women are less likely to report symptoms of depression than their unmarried counterparts. The mental health benefits of marriage are greater for men than for women. Moreover, other variables, such as marital satisfaction, self-rated health, and employment status are more powerful predictors of emotional well-being in midlife than marital status per se. The quality of marriage affects depressive symptoms more strongly for women than men.

Legal Issues Related to Dismissing Students for Clinical Deficiencies

Clinical faculty have a legal, ethical, and professional obligation to evaluate students' clinical performance to ensure safe practitioners. However, many clinical faculty members fear litigation and hesitate to give an unsatisfactory grade to students who do not meet established standards. If the decision to assign a failing clinical grade was "careful and deliberate" and the student was afforded due process, the principle of judicial deference emerges to protect the clinical instructor and the educational institution.

Ecological half-life of 137Cs in fish from a stream contaminated by nuclear reactor effluents

Radiocesium (137Cs) concentrations were determined during 1974, 1981 and 1998 for seven species of fish inhabiting a stream (Steel Creek) contaminated by effluents from a nuclear reactor to examine the decline of this radionuclide in a natural ecosystem. Median 137Cs concentrations were highest in Micropterus salmoides (largemouth bass) during each year of the investigation (1974 = 6.67 Bq g(-1) dry wt. of whole body; 1981 = 3.72 Bq g(-1); 1998 = 0.35 Bq g(-1)), but no patterns of differences were observed among Aphredoderus sayanus (pirate perch), Esox americanus (redfin pickerel), Lepomis auritus (redbreast sunfish), L. gulosus (warmouth), L. punctatus (spotted sunfish), and Notropis cummingsae (dusky shiner). Results demonstrated a rapid decline in 137Cs within fish from Steel Creek during the 24-year period. For example, 137Cs concentrations in all fish species declined significantly among years, even after accounting for radioactive decay. The observed percent declines in 137Cs concentrations of individual species were 3-4 times greater between 1974 and 1981 compared to that expected by physical decay alone, and 2-3 times greater during 1981-1998. Ecological half-lives (EHLs) of 137Cs in fish ranged from 4.43 years in A. sayanus to 6.53 years in L. gulosus. The EHL for 137Cs in all fish species combined was 5.54 years. Current levels of 137Cs in fish from Steel Creek (1.16 Bq g(-1) dry wt. of whole body to below detection limits) indicate that the consumption of fish from this ecosystem poses little risk to humans and sensitive wildlife species. These results demonstrate the importance of incorporating the concept of ecological half-life into determinations concerning the length and severity of potential risks associated with radiocontaminants.

Readiness to change: newspaper coverage of tobacco farming and diversification

Diversification, like tobacco use prevention and cessation, is an important public health concern. The multilevel patterns of tobacco dependency suggest the need for public health approaches to the "tobacco problem." To understand how newspaper and wire service journalists cover issues involving diversification among tobacco farmers, the authors performed a content analysis of a subset of 100 articles on diversification and tobacco farming. Prochaska and DiClemente's stages of change model was applied to the "problem behavior" of tobacco farming. Among news accounts relating to tobacco farmers or tobacco farming, print media accounts gave relatively little attention to the issue of diversification. Farmers in the sample of news accounts were generally cognizant of pressures to diversify away from reliance on tobacco cultivation but were frustrated due to obstacles to diversification such as limited diversification options and relative absence of infrastructure supports. Community leaders and policy-relevant sources generally supported diversification.

Optical model of the blood in large retinal vessels

Several optical techniques that investigate blood contained within the retinal vessels are available or under development. We present a mechanical model that simulates the optical properties of the eye, the retinal vessels, and the ocular fundus. A micropipette is chosen as the retinal vessel model, and a mechanical housing is constructed to simulate the eyeball. Spectralon is used to simulate the retinal layers. Filling the eye with fluid index matched to the glass pipette eliminates reflection and refraction effects from the pipette. An apparatus is constructed and used to set the oxygen, nitrogen, and carbon dioxide concentrations in whole human blood. These whole blood samples are pumped through the pipette at 34 microL/min. Measurements made in the model eye closely resemble measurements made in the human eye. This apparatus is useful for developing the science and testing the systems that optically investigate blood and blood flow in the large retinal vessels.

Adjuvant activities of immune response modifier R-848: comparison with CpG ODN

R-848 and imiquimod belong to a class of immune response modifiers that are potent inducers of cytokines, including IFN-alpha, TNF-alpha, IL-12, and IFN-gamma. Many of these cytokines can affect the acquired immune response. This study examines the effects of R-848 on aspects of acquired immunity, including immunoglobulin secretion, in vivo cytokine production, and Ag-specific T cell cytokine production. Results are compared with those of Th1 CpG ODN. R-848 and CpG ODN are effective at skewing immunity in the presence of Alum toward a Th1 Ab response (IgG2a) and away from a Th2 Ab response (IgE). R-848 and CpG ODN are also capable of initiating an immune response in the absence of additional adjuvant by specifically enhancing IgG2a levels. Both R-848 and imiquimod showed activity when given subcutaneously or orally, indicating that the compound mechanism was not through generation of a depot effect. Although CpG ODN behaves similarly to R-848, CpG ODN has a distinct cytokine profile, is more effective than R-848 when given with Alum in the priming dose, and is active only when given by the same route as the Ag. The mechanism of R-848's adjuvant activity is linked to cytokine production, where increases in IgG2a levels are associated with IFN-alpha, TNF-alpha, IL-12, and IFN-gamma induction, and decreases in IgE levels are associated with IFN-alpha and TNF-alpha. Imiquimod also enhances IgG2a production when given with Ag. The above results suggest that the imidazoquinolines R-848 and imiquimod may be attractive compounds for use as vaccine adjuvants and in inhibiting pathological responses mediated by Th2 cytokines.

Age and other risk factors for neuropsychologic decline in patients undergoing coronary artery bypass graft surgery

OBJECTIVE

To evaluate if increasing age is a major determinant of long-term neuropsychologic (NP) dysfunction in patients undergoing coronary artery bypass graft (CABG) surgery.

DESIGN

Prospective cohort study.

SETTING

A single university hospital.

PARTICIPANTS

Three hundred eighty-one patients undergoing elective CABG surgery.

INTERVENTIONS

Baseline preoperative and intraoperative characteristics were assessed for all patients. A comprehensive NP test battery was conducted preoperatively and at 1 month postoperatively.

MEASUREMENTS AND MAIN RESULTS

Of the initial 381 patients, 319 (84%) returned for the 1-month visit. The overall incidence of an NP deficit was 21.6%. There was no significant difference seen with increasing age, although a trend was observed with highest NP deficit rate in the older than 65 age group. Other preoperative risk factors, including gender, education level, and preexisting diseases, were nonsignificant. Intraoperative variables were evaluated and revealed no significant differences across the age groups.

CONCLUSIONS

This cohort study did not find an increased incidence of NP deficits in elderly patients after CABG surgery. It has addressed the limitations of other studies, however, with (1) a comprehensive NP test battery, (2) longer-term follow-up, and (3) adequate sample size.

Correlation between pretreatment levels of interferon response genes and clinical responses to an immune response modifier (Imiquimod) in genital warts

Imiquimod (IQ) has been successfully used in treatment of genital warts. In clinical settings, patients responded well but wart reduction rates varied. Our aim was to find a correlation between clinical responses and pretreatment (constitutive) levels of genes that might be involved in the molecular action of IQ. Since IQ is a cytokine inducer, we analyzed levels of expression of genes of the JAK/STAT signaling pathway and their inhibitors as well as interferon response factors (IRFs) in pretreatment biopsy specimens from complete responders (99 to 100% wart reduction rate) versus incomplete responders (75 to 92% wart reduction rate) by reverse transcription-PCR. We found that mRNA levels of signal transducer and activator of transcription 1 (STAT1) and IRF1 were higher in complete responders than in incomplete responders. Incomplete responders expressed larger amounts of STAT3, IRF2, and protein inhibitor of activated STAT1 (PIAS1) mRNAs compared to complete responders before IQ treatment. We hypothesize that high-level expression of STAT1 and IRF1 is advantageous for a better IQ response. The observed differences in constitutive mRNA levels of these genes may be the consequence of alterations in cellular differentiation and/or variable expression of endogenous interferons. Previous in vitro studies showed that keratinocyte differentiation coordinates the balance between positive and negative signals along the JAK/STAT pathway by regulating the IRF1:IRF2 and STAT1:PIAS1 ratios and thus affecting induction of IQ-inducible genes. Specifically, differentiation supports constitutive expression of STAT1 and IRF1 mRNAs but not expression of IRF2 and PIAS1. Our data are in good agreement with studies that showed the importance of STAT1 in cytokine induction and activation of interferon-responsive genes by IQ.

Structural changes accompanying pH-induced dissociation of the beta-lactoglobulin dimer

We have used NMR spectroscopy to determine the three-dimensional (3D) structure, and to characterize the backbone dynamics, of a recombinant version of bovine beta-lactoglobulin (variant A) at pH 2. 6, where the protein is a monomer. The structure of this low-pH form of beta-lactoglobulin is very similar to that of a subunit within the dimer at pH 6.2. The root-mean-square deviation from the pH 6.2 (crystal) structure, calculated for backbone atoms of residues 6-160, is approximately 1.3 A. Differences arise from the orientation, with respect to the calyx, of the A-B and C-D loops, and of the flanking three-turn alpha-helix. The hydrophobic cavity within the calyx is retained at low pH. The E-F loop (residues 85-90), which moves to occlude the opening of the cavity over the pH range 7.2-6.2, is in the "closed" position at pH 2.6, and the side chain of Glu89 is buried. We also carried out measurements of (15)N T(1)s and T(2)s and (1)H-(15)N heteronuclear NOEs at pH 2.6 and 37 degrees C. Although the residues of the E-F loop (residues 86-89) have the highest crystallographic B-factors, the conformation of this loop is reasonably well defined by the NMR data, and its backbone is not especially mobile on the pico- to nanosecond time scale. Several residues (Ser21, Lys60, Ala67, Leu87, and Glu112) exhibit large ratios of T(1) to T(2), consistent with conformational exchange on a micro- to millisecond time scale. The positions of these residues in the 3D structure of beta-lactoglobulin are consistent with a role in modulating access to the hydrophobic cavity.

Effect of multiple light paths on retinal vessel oximetry

Techniques for noninvasively measuring the oxygen saturation of blood in retinal arteries and veins are reported in the literature, but none have been sufficiently accurate and reliable for clinical use. Addressing the need for increased accuracy, we present a series of oximetric equations that explicitly consider the effects of backscattering by red blood cells and lateral diffusion of light in the ocular fundus. The equations are derived for the specific geometry of a scanning-beam retinal vessel oximeter; however, the results should also be applicable to photographic oximeters. We present in vitro and in vivo data that suggest the validity of these equations.

Complement resistance-related traits among Escherichia coli isolates from apparently healthy birds and birds with colibacillosis

In this study, 294 Escherichia coli isolates from birds with colibacillosis were collected from disease outbreaks throughout the United States and were compared with 75 fecal E. coli isolates of apparently healthy chickens by their possession of several purported virulence genes, resistance to rough-lipopolysaccharide-specific bacteriophages (rLPSr), and elaboration of capsule. Traits were selected for study on the basis of their association with complement resistance. The genes targeted in this study included those encoding colicin V (cvaC) and the outer membrane proteins TraT (traT), OmpA (ompA), and Iss (iss). No significant differences were found between the two groups of isolates in the occurrence of cvaC-, traT-, or ompA-homologous sequences or in rLPSr. Only a few isolates were encapsulated, and the isolates of healthy birds were significantly more likely to be encapsulated than were the isolates of sick birds. However, iss, whether detected through hybridization or amplification, was found in more of the disease-associated isolates than in those of healthy birds. This difference was highly significant. Further, iss sequences were widely distributed among isolates of different serotypes from various avian host species and sites within these hosts. Such results suggest that possession of the iss sequence by an avian E. coli isolate may be a good indicator of that isolate's potential to cause disease. This association warrants further study because iss and the protein it encodes may be useful targets of future colibacillosis control efforts.

Retinal imaging techniques in diabetes

Diabetic retinopathy is progressive, and detection early is essential for the prevention of blindness. Doppler flowmetry, retinal photography, scanning laser ophthalmoscopy, and retinal oximetry measurements may identify proliferative disease early. Drawbacks of these methods include lack of compliance, failure to refer, and failure to identify disease early. As a result, diabetic retinopathy is a leading cause of blindness. Our retinal oximeter measures the blood oxygen saturation in the large vessels of the retina near the optic disc. Retinal vessel oxygen saturations measured with our instrument are sensitive indicators of blood loss and hypoxia in swine. We are generating scientific data that suggests that retinal vessel oxygen saturations may be used to identify retinal hypoxia prior to changes in retinal vessel architecture. We expect to study humans within the next two years, and a clinically useful eye oximeter should be available in the near future.

A randomized, controlled, safety study using imiquimod for the topical treatment of anogenital warts in HIV-infected patients. Imiquimod Study Group

OBJECTIVE

To assess the safety of imiquimod, an immune response modifier, in the topical treatment of external anogenital warts in HIV-infected patients.

SETTING

Clinical sites in the United Kingdom (eight) and the United States (five).

DESIGN

A prospective, randomized, double-blind, vehicle-controlled study of imiquimod 5% cream or vehicle applied for 8+/-2 h three times per week for a maximum of 16 weeks in HIV-seropositive males (n = 97) and females (n = 3) aged 18 years or more with clinically diagnosed external anogenital warts, CD4 T lymphocyte count of > or = 100 x 10(6) cells/l and Karnofsky score > or = 70.

MAIN OUTCOME MEASURES

Safety was assessed through the incidence and severity of local skin reactions and other adverse events, and through clinical laboratory tests. Wart clearance was documented by two-dimensional measurements of warts and by photography.

RESULTS

Among the patients treated with imiquimod (n = 65) and vehicle (n = 35), the most common local skin reaction was erythema, (41.9 and 26.7%, respectively) and the incidence of patients reporting at least one adverse event was 69.2 and 65.7%, respectively. No clinically meaningful differences or changes in laboratory values were observed between treatment groups, nor were drug-related adverse effects observed in regard to HIV disease. While there was no significant difference between treatment groups in the number of patients who totally cleared their baseline warts (imiquimod 11% versus vehicle 6%, P = 0.488), more imiquimod-treated patients experienced a > or = 50% reduction in baseline wart area (38% versus 14%, P = 0.013).

CONCLUSION

Most local skin reactions were mild and no adverse effects on HIV disease were observed. Topically applied imiquimod 5% cream reduced wart area and may have clinical utility in treating external anogenital warts in some HIV-infected patients.

Modeling the impact of treatment options in genital warts: patient-applied versus physician-administered therapies

With the availability of new patient-applied treatments for genital and perianal warts, medical providers, physician groups, and health systems are reassessing the role of physician-administered therapies. Two key questions are: how cost-effective are physician- versus patient-administered therapies and, given patient preferences for the convenience and privacy associated with the latter therapies, which of the 2 presently available treatments-imiquimod and podofilox-is most appropriate? The purpose of this article is to examine, from the perspective of the health care purchaser, these questions and to undertake a pharmacoeconomic analysis of the direct cost-effectiveness of therapy options, given targets being set for the outcomes of genital warts therapy. The analysis employs a synthetic, decision-modeling framework in which data on sustained clearance and the direct costs of treatment are drawn from both clinical studies and previous studies on the resources used to support treatment. Once targets are set-and it is proposed here that physicians should aim for at least a 50% sustained clearance rate for genital warts--it becomes clear that in cost per sustained clearance terms, imiquimod, as first-line therapy, is the most cost-effective intervention. If we compare imiquimod with podofilox as first-line therapy (with cryotherapy as the second-line option), the cost per sustained clearance for the imiquimod treatment sequence is $1367 compared with the podofilox-initiated sequence of $1508.

Enhancement of the innate and cellular immune response in patients with genital warts treated with topical imiquimod cream 5%

The mechanism of action of imiquimod 5% cream applied topically to patients with genital warts was evaluated in a double-blind, placebo-controlled study. Imiquimod (16 patients) or placebo (three patients) was applied three times per week for up to 16 weeks. All imiquimod-treated patients had a > or =75% reduction in total wart area while only one of three placebo-treated patients had a similar reduction. Wart biopsies were taken at prestudy, week 6, and end of treatment. Polymerase chain reaction (PCR) for human papillomavirus (HPV) DNA and reverse transcriptase (RT)-PCR for messenger (m)RNAs were used to identify cytokines, cellular markers, viral gene products, and cell cycle markers in these biopsies. Treatment with imiquimod, an immune response modifier, stimulated significant increases in mRNA for interferon (IFN)-alpha, IFN-gamma and 2',5' oligoadenylate synthetase (2',5'-AS) as well as a tendency towards increases in tumor necrosis factor (TNF)-alpha and interleukin-12 p40. Significant increases in mRNA for CD4 and a trend toward increases in CD8 were also observed in imiquimod-treated patients, suggesting activation of a cell mediated immune response. Imiquimod administration was also associated with a significant decrease in viral load as measured by HPV DNA and L1 mRNA. The effects on HPV markers were accompanied by an apparent decrease in mRNA expression for markers of cell proliferation and an increase in mRNA for markers of keratinocyte differentiation and tumor suppressors.

Newspaper and wire service coverage of tobacco farmers

This study examined print media coverage of tobacco farmers from the perspective of agenda setting, or the extent to which information is available to the public and perceived as important. A content analysis of 743 articles published between January 1, 1995 and June 30, 1997 was completed. The number of articles increased from 1995 to 1997. Of the topics analyzed, articles on tobacco settlement (7.1% of total) and diversification (15.6% of total) were the least prevalent. Because the settlement discussions did not occur until 1997 (when it comprised 26.4% of the total in the first 6 months), diversification was consistently the least covered topic. The two most frequent topics covered were tobacco companies (36.2%) and the tobacco price support program (32.3%). Except for one 6 month interval, there were substantially more articles in local/regional publications than in national publications. Public health professionals have called for tobacco farmers to diversify to non-tobacco enterprises. Yet, there is little discussion of diversification in print media. Without more attention to diversification, the public and policy makers will be ill-informed about opportunities and obstacles in this regard.

The cost effectiveness of patient-applied versus provider-administered intervention strategies for the treatment of external genital warts

OBJECTIVE

External genital warts are one of the fastest growing sexually transmitted diseases in the United States today. Two forms of therapy are available: provider-administered and patient-applied. In the most widely used provider-administered ablative therapies, sustained clearance rates range from 18.5% to 40.1%. With nonablative, patient-applied therapies, which are typically more acceptable to patients, sustained clearance rates range from 19.6% with podofilox gel to 44.0% with imiquimod cream. The purpose of this study, given the range of therapies available, their cost differences, and clinical trial-reported differences in rates of sustained clearance, is to determine which therapy modalities, from the providers' perspective, are the most cost effective and which are likely to be the most acceptable to the patient population.

STUDY DESIGN

We consider the cost effectiveness of the two patient-applied therapies as first-line therapy followed by provider-administered ablative treatment as second-line therapy. A decision-analytic model framework is developed, with data drawn both from clinical trials and from previously published studies.

RESULTS

When considering a two-stage therapy model, with an average sustained clearance rate of 30% assumed for provider-administered ablative therapies, estimated costs per sustained cleared patient are $1265 for patients initially treated with imiquimod and $1304 for patients initially treated with podofilox gel.

CONCLUSIONS

Initial treatment with imiquimod is the preferred intervention option as it yields a 39% greater sustained clearance rate than podofilox gel while being 3% less costly per successful outcome.

Optimum wavelength combinations for retinal vessel oximetry

Several investigators have demonstrated techniques for noninvasive measurement of the oxygen saturation of blood in retinal arteries and veins. These techniques have been based on measuring the optical density of a retinal vessel at multiple wavelengths and on calculating the oxygen saturation on the basis of the known absorption coefficients of hemoglobin and oxyhemoglobin. A technique is presented for determining the optimum wavelengths for retinal oximetry measurements. What is believed to be a novel wavelength combination of 488, 635, and 905 nm is found to provide excellent oxygen sensitivity across a broad range of typical vessel diameters and saturations. The use of this wavelength combination should allow for the most accurate retinal saturation measurements made to date.

Baculoviral expressed HLA class I heavy chains used to screen a synthetic peptide library for allele-specific peptide binding motifs

Recombinant baculoviruses encoding truncated HLA-A*0101 and HLA-A*0201 class I heavy chains have been isolated and used to infect lepidopteran cells. Proteins overexpressed in this system were glycosylated, and consisted of 282 amino acid residues after signal sequence cleavage. These class I heavy chains could fold into their native conformation in the presence of recombinant human beta2-microglobulin expressed in Escherichia coli and a synthetic peptide library of nonamers bound to resin-support beads. Reconstitution into native ternary complexes was detected using a conformation specific monoclonal antibody followed by isolation and sequencing of the bound peptides. The motifs obtained for HLA-A1.1 and HLA-A2.1 peptides are similar although more extensive than those derived from sequencing endogenous peptides. This approach selects peptides which form very stable complexes regardless of whether these peptides are generated under physiological conditions, thereby providing unique supplementary data for predicting and designing CTL epitopes. This method is based solely on peptide binding to the class I molecule and is therefore independent of any constraints imposed by endogenous intracellular processing or transport systems. A comparison of the two motifs provides an opportunity to distinguish between the requirements of binding from those arising as a function of intracellular processing or transport. Our findings are not consistent with a recent report suggesting that constraints on the COOH termini of these peptides can be attributed to the effects of either intracellular processing or transport. We find that the carboxy termini in the class I peptides analyzed to date mimic the endogenous data, suggesting that residues in this position contribute to binding affinity.