Safety of baclofen versus tizanidine for older adults with musculoskeletal pain

BACKGROUND

Baclofen and tizanidine are both muscle relaxants that carry the risk for neuropsychiatric events in older adults but there is a lack of data directly comparing their safety. This study aimed to investigate the relative risk between these two medications in causing injury and delirium in older adults.

METHODS

This was a retrospective cohort study that was completed in an integrated healthcare system in the United States and included patients aged 65 years or older who started baclofen or tizanidine for the treatment of musculoskeletal pain from January 2016 through December 2018. Outcomes included new incidence of injury (concussion, contusion, dislocation, fall, fracture, or other injuries) and delirium. The cohort was followed from the initiation of therapy until the first occurrence of any of the following events: end of the index drug exposure, end of health plan membership, death, or the study end date of December 31st, 2019. Descriptive statistics were used to compare baseline patient characteristics between baclofen and tizanidine treatment groups. Cox proportional hazards model was used to calculate adjusted hazard ratios (HRs) with 95% confidence intervals.

RESULTS

The final study cohort included 12,101 and 6,027 older adults in the baclofen and tizanidine group respectively (mean age 72.2 ± 6.2 years old, 59% female). Older adults newly started on baclofen had a greater risk of injury (HR = 1.54, 95% CI = 1.21-1.96, P = < 0.001) and delirium (HR = 3.33, 95% CI = 2.11-5.26, p = <0.001) compared to those started on tizanidine.

CONCLUSION

The results of this study suggest that baclofen is associated with higher incidences of injury and delirium compared to tizanidine when used for the treatment of musculoskeletal pain. Future studies should investigate if these risks are dose-related and include a comparison group not exposed to either drug.

Dementia and readmission risk in patients with heart failure participating in a transitional care program

BACKGROUND

Cognitive impairment is prevalent in patients hospitalized for heart failure (HF). We aimed to generate further evidence on the value of dementia screening in hospitalized HF patients by examining whether and when dementia would be an independent risk factor for 30-day readmission while modeling permutations of known risk factors such as patient demographics, disease burden, prior utilization, and index hospitalization characteristics.

METHODS AND RESULTS

A retrospective cohort study was employed, consisting of 26,128 patients (2,075 or 7.9% with dementia) in a transitional care program post HF hospitalization. The overall 30-day all-cause readmission rate was 18.1%. Patients with dementia had higher unadjusted rates of readmission (22.0 vs 17.8%) and death (4.5 vs. 2.2%) within 30 days post hospitalization, compared to those without dementia. Hierarchical multivariable proportional hazards regression results showed that dementia independently predicted readmission when both patient demographics and disease burden variables were controlled for (HR=1.15, p=0.02). However, the association between dementia and readmission was attenuated in the full model when prior utilization and index hospitalization characteristics were added (HR=1.04, p=0.55). For dementia patients, Charlson comorbidity index, prior ED visits, and length of stay were significant risk factors of readmission.

CONCLUSIONS

The presence of dementia and the predictors of 30-day readmission in those with dementia may help identify this subset of high-risk HF patients for potential efforts to improve their prognosis.

Refining the Definition of Polypharmacy and Its Link to Disability in Older Adults: Conceptualizing Necessary Polypharmacy, Unnecessary Polypharmacy, and Polypharmacy of Unclear Benefit

The term polypharmacy in older adults is generally used in a pejorative context in the medical literature. Because of its link to geriatric syndromes and disability, the avoidance of polypharmacy is usually recommended in older adults as a strategy to optimize functional status. However, there are many polypharmacy regimens based on high-quality trials that clearly reduce the risk of disability in older adults. Other guidelines for older adults recommend the use of additional medications that may or may not be evidence based and that may or may not reduce disability. Therefore, we propose that, in the geriatric literature, polypharmacy now be categorized as "necessary polypharmacy," "unnecessary polypharmacy," or "polypharmacy of unclear benefit." In this article, we discuss the 3 categories of polypharmacy and give examples on each polypharmacy regimen and its potential relationship to disability in older adults.

The Risk of Pneumonia in Older Adults Using Nonbenzodiazepine Hypnotics

BACKGROUND

Previous studies have shown an increased risk of pneumonia with benzodiazepines (BZD) and an increased risk of any infection with non-BZD hypnotics, but no analysis has specifically investigated the risk of pneumonia with non-BZD hypnotic use.

OBJECTIVE

To evaluate the risk of pneumonia associated with non-BZD hypnotic use in the elderly.

METHODS

This was a retrospective case-control study of members aged 65 years and older enrolled in an integrated health care system. Cases were identified as patients aged 65 years and older with a diagnosis of pneumonia from January 2011 to December 2012. Controls were matched in a 4:1 ratio to cases based on age, gender, and active enrollment. Non-BZD hypnotic exposure was evaluated for all cases and controls 1 year before the index date. Proximity of exposure to index date and duration of use were analyzed. Conditional logistic regression adjusted for covariates was performed.

RESULTS

We identified 51,029 cases with pneumonia and matched 188,391 controls without pneumonia. Of the cases with pneumonia, 5.5% (2,790) of cases had exposure to a non-BZD hypnotic, compared with 3.4% (6,345) of controls. Non-BZD hypnotic exposure was associated with an increased risk of pneumonia (OR = 1.14; 95% CI = 1.08-1.20). When exposure was stratified by proximity to index date, only current exposure was associated with an increased risk of pneumonia (OR = 1.27; 95% CI = 1.18-1.36). Short-term exposure was associated with a relatively higher risk of pneumonia (OR = 1.57; 95% CI = 1.39-1.77) compared with long-term use (OR = 1.16; 95% CI = 1.06-1.25).

CONCLUSIONS

Current use of non-BZD hypnotics in older adults is associated with an increased risk of pneumonia. The findings of this study provide additional support for reducing the use of non-BZD hypnotics in older adults and for pursuing safer alternatives for treating insomnia.

DISCLOSURES

No outside funding supported this study. At the time of this study, Jung was a PGY2 resident in drug information at Kaiser Permanente Drug Information Services. All authors are employed by Kaiser Permanente and report no other potential financial conflicts of interest. Study concept and design were contributed by Jung, Spence, Lee, and Gibbs. Jung, Spence, and Hui were responsible for data collection, and data interpretation was performed by Jung and Spence, with assistance from Escasa, Lee, and Hui. The manuscript was primarily written by Jung, along with Spence and Escasa, and revised by Spence, Escasa, and Lee, along with the other authors.

Improving Care in Older Patients with Diabetes: A Focus on Glycemic Control

Diabetes affects more than 25% of Americans older than age 65 years. The medical care of older patients must differ from the care of their younger counterparts. Older patients are at high risk of drug toxicity. A hemoglobin A1c (HbA1c) level less than 7.0% has historically been the goal of all patients with diabetes, regardless of age. Recent research has demonstrated that using medications to achieve such tight glycemic control is not necessary and is often not safe.This article discusses the seminal research findings that strongly suggest that HbA1c goals should be relaxed in older patients. The authors then recommend an age-specific and functionally appropriate HbA1c reference range for patients receiving medications to improve glycemic control. Other interventions are suggested that should make diabetes care safer in older patients receiving hypoglycemic medications.

Mitochondrial DNA damage by bleomycin induces AML cell death

Mitochondria contain multiple copies of their own 16.6 kb circular genome. To explore the impact of mitochondrial DNA (mtDNA) damage on mitochondrial (mt) function and viability of AML cells, we screened a panel of DNA damaging chemotherapeutic agents to identify drugs that could damage mtDNA. We identified bleomycin as an agent that damaged mtDNA in AML cells at concentrations that induced cell death. Bleomycin also induced mtDNA damage in primary AML samples. Consistent with the observed mtDNA damage, bleomycin reduced mt mass and basal oxygen consumption in AML cells. We also demonstrated that the observed mtDNA damage was functionally important for bleomycin-induced cell death. Finally, bleomycin delayed tumor growth in xenograft mouse models of AML and anti-leukemic concentrations of the drug induced mtDNA damage in AML cells preferentially over normal lung tissue. Taken together, mtDNA-targeted therapy may be an effective strategy to target AML cells and bleomycin could be useful in the treatment of this disease.

Targeting Mitochondria with Avocatin B Induces Selective Leukemia Cell Death

Treatment regimens for acute myeloid leukemia (AML) continue to offer weak clinical outcomes. Through a high-throughput cell-based screen, we identified avocatin B, a lipid derived from avocado fruit, as a novel compound with cytotoxic activity in AML. Avocatin B reduced human primary AML cell viability without effect on normal peripheral blood stem cells. Functional stem cell assays demonstrated selectivity toward AML progenitor and stem cells without effects on normal hematopoietic stem cells. Mechanistic investigations indicated that cytotoxicity relied on mitochondrial localization, as cells lacking functional mitochondria or CPT1, the enzyme that facilitates mitochondria lipid transport, were insensitive to avocatin B. Furthermore, avocatin B inhibited fatty acid oxidation and decreased NADPH levels, resulting in ROS-dependent leukemia cell death characterized by the release of mitochondrial proteins, apoptosis-inducing factor, and cytochrome c. This study reveals a novel strategy for selective leukemia cell eradication based on a specific difference in mitochondrial function.

Comparison of Strain in GaN-Based Blue Light-Emitting Diode Grown on Silicon(111) and Sapphire Substrates

We compare the strain states and device performances of GaN-based blue light-emitting diodes (LEDs) grown on Si(111) and sapphire substrates. The strain characteristics are investigated using micro-Raman spectroscopy and high-resolution transmission electron microscopy. These analyses reveal that GaN layer grown on Si has a residual tensile strain in contrast to a compressive strain for GaN on sapphire, and quantum wells (QWs) on GaN/Si experience reduced lattice mismatch than those of GaN/sapphire. When external quantum efficiencies of LED on sapphire and Si substrates are compared, the LED on Si shows better efficiency droop characteristics and this is attributed to a decrease in piezo-electric field strength in InGaN/GaN layers owing to reduced lattice mismatch.

Estimation of pork quality traits using exsanguination blood and postmortem muscle metabolites

The current study was designed to estimate the pork quality traits using metabolites from exsanguination blood and postmortem muscle simultaneously under the Korean standard pre- and post-slaughter conditions. A total of 111 Yorkshire (pure breed and castrated male) pigs were evaluated under the Korean standard conditions. Measurements were taken of the levels of blood glucose and lactate at exsanguination, and muscle glycogen and lactate content at 45 min and 24 h postmortem. Certain pork quality traits were also evaluated. Correlation analysis and multiple regression analysis including stepwise regression were performed. Exsanguination blood glucose and lactate levels were positively correlated with each other, negatively related to postmortem muscle glycogen content and positively associated with postmortem muscle lactate content. A rapid and extended postmortem glycolysis was associated with high levels of blood glucose and lactate, with high muscle lactate content, and with low muscle glycogen content during postmortem. In addition, these were also correlated with paler meat color and reduced water holding capacity. The results of multiple regression analyses also showed that metabolites in exsanguination blood and postmortem muscle explained variations in pork quality traits. Especially, levels of blood glucose and lactate and content of muscle glycogen at early postmortem were significantly associated with an elevated early glycolytic rate. Furthermore, muscle lactate content at 24 h postmortem alone accounted for a considerable portion of the variation in pork quality traits. Based on these results, the current study confirmed that the main factor influencing pork quality traits is the ultimate lactate content in muscle via postmortem glycolysis, and that levels of blood glucose and lactate at exsanguination and contents of muscle glycogen and lactate at postmortem can explain a large portion of the variation in pork quality even under the standard slaughter conditions.

Making hospitals safer for older adults: updating quality metrics by understanding hospital-acquired delirium and its link to falls

The medical care of hospitalized geriatric patients must differ from the care of younger adults. Because of reduced "reserve capacity," hospitalized older adults are at high risk of development of geriatric syndromes such as delirium and falls. Geriatric syndromes often lead to functional decline and dependence. Patients who experience geriatric syndromes in the hospital are more likely to have a longer length of stay, higher risk of readmissions, and worse medical outcomes. Incident delirium in hospitalized geriatric patients has been shown to be preventable by intervening in established risk factors. Prevention of hospital-related falls has not been consistently demonstrated. Analysis from Kaiser Permanente data demonstrated a correlation with delirium and hospital-related falls. We propose that age-specific quality metrics should be made to reduce the risk of the development of geriatric syndromes in hospitalized older adults. By preventing delirium, we believe that health care practitioners can reduce hospital-related falls in geriatric patients and improve the quality of care delivered to hospitalized older adults. An illustrative fictional case study is presented.

Risk of injury associated with skeletal muscle relaxant use in older adults

BACKGROUND

The use of skeletal muscle relaxants (SMRs) among older adults is associated with sedation and confusion, which may lead to an increased risk of falls and injuries. SMRs continue to be used among older adults, although they are on the Beers list as drugs to avoid in the elderly.

OBJECTIVE

To investigate the relationship between SMR use and subsequent risk of injury.

METHODS

This was a retrospective case-control study of members aged 65 years or older enrolled in an integrated health care system. Cases were defined as patients with a documented injury resulting in either a hospitalization or an emergency department or urgent care visit from January 2009 through December 2010. Cases were matched to controls in a 1:4 ratio by age and sex. Patients had to be enrolled and alive on the date of an injury (index date). SMR exposure for all cases and controls was evaluated within 60 days prior to the index date. Conditional logistic regression adjusted for covariates was performed, with risk estimates presented as odds ratios with 95% confidence intervals.

RESULTS

From a base population of 322,806 older adults, we identified 27,974 cases of injury and 104,303 matched controls. Among the cases, 365 (1.30%) used an SMR; among the controls, 801 (0.77%) used an SMR in the 60 days prior to the index date. After adjustment for demographic and clinical covariates, risk of injury was significantly increased for patients using an SMR compared to no use (OR 1.32, 95% CI 1.16-1.50; p < 0.001). Carisoprodol was associated with an increased risk of injury (OR 1.73, 95% CI 1.04-2.88; p = 0.036), as were methocarbamol (OR 1.42, 95% CI 1.16-1.75; p = 0.001) and cyclobenzaprine (OR 1.22, 95% CI 1.02-1.45; p = 0.029).

CONCLUSIONS

Older adults using SMRs have an increased risk of injury. These findings provide evidence to support current recommendations to avoid the use of SMRs in elderly patients.

Effects of hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 1 polymorphisms on fat androstenone level and gene expression in Duroc pigs

A high level of androstenone in porcine adipose tissue is a major factor contributing to boar taint. Porcine hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 1 (3β-HSD, also known as HSD3B1) plays a key role in the hepatic metabolism that catalyzes androstenone to β-androstenol. Therefore, 3β-HSD is a candidate gene for boar taint. This study aimed to investigate functional 3β-HSD polymorphisms in Duroc pigs. We found eight single nucleotide polymorphisms (SNPs) in the full-length porcine 3β-HSD. Four of the SNPs had restriction enzyme sites, and we genotyped them in 147 uncastrated male Duroc pigs using a polymerase chain reaction-restriction fragment length polymorphism method. Pigs with the GG genotype at the g.165262G>A locus (SNP5) had significantly lower androstenone levels than did those with other genotypes (P = 0.030). SNP5 also was associated with differences in 3β-HSD mRNA levels: pigs with the GG genotype had higher levels than those with other genotypes (P = 0.019). The SNP5 polymorphism could affect the hepatic catabolism of androstenone and consequently impact androstenone accumulation in the adipose tissue. Therefore, SNP5 in the 3β-HSD of Duroc pigs could be a useful selective marker for decreasing boar taint.

Avian polyomavirus identified in a nestling Gouldian finch (Erythrura gouldiae) in New Zealand

Abstract

CASE HISTORY

Four 4-5-month-old nestlings and one adult in a commercial aviary of 53 Gouldian finches (Erythrura gouldiae) died over a 2-week period in July 2000.

PATHOLOGICAL FINDINGS

One nestling was necropsied and showed bronze-tinged skeletal muscles, a swollen liver with haemorrhagic margins and numerous haemorrhages on serosal surfaces. The histological lesions included multifocal hepatic necrosis and haemorrhage associated with the presence of large clear or basophilic intranuclear inclusions in hepatocytes and Kupffer cells suggestive of avian polyomavirus infection. Similar inclusion bodies were present in splenic histiocytes.

MOLECULAR BIOLOGY

DNA was subsequently extracted from archived portions of liver, spleen, gizzard, heart, lung and kidney. A broad spectrum nested PCR was used to detect polyomavirus which sequence analysis confirmed as finch polyomavirus.

DIAGNOSIS

Avian polyomavirus.

CLINICAL RELEVANCE

Avian virus infections such as polyomavirus should be suspected in cases of sudden death in nestlings, particularly in susceptible species such as psittacine and passerine birds. The archiving of tissues from unconfirmed disease outbreaks provides a valuable resource for retrospective investigations.

Genetic variation in dosage effects in maize aneuploids

In maize (Zea mays L.), the consequences of aneuploidy have been well documented, however, genetic variation in the responses to aneuploidy has not been examined. Using simple B-A translocation stocks to generate a dosage series involving segments from 14 chromosome arms, we tested for the presence of genetic variation for dosage responses in maize by examining reciprocal and maternal genotype effects on the dosage responses. Reciprocal effects examined whether there were differences between two distinctly different inbred backgrounds, Mo17Ht and B73Ht, in how they responded to loss or gain of a B73Ht segment in the Mo17Ht x B73Ht (TB) F1 cross versus a Mo17Ht segment in the B73Ht x Mo17Ht (TB) F1 cross. Maternal genotype effects questioned whether different inbred backgrounds, Sc41R, T8, and either Mo17Ht or B73Ht (depending on the male), when used as females responded differently to the loss or gain of a chromosome arm segment from the same male (either B73Ht TB or Mo17Ht TB) in an F1 cross. Numerous examples of reciprocal and maternal genetic effects were identified in this study. Most of the genetic effects were due to differences in magnitude of response rather than direction; however, tassel-branch number involving the 5S chromosome segment in the B73Ht male background and the 7L chromosome segment in the Mo17Ht male background showed a trend toward the maternal genotype effects being due to differences in the direction of the response. Key words : quantitative traits, corn, B-A translocations, dosage analysis.

Dosage effects on morphological and quantitative traits in maize aneuploids

Dosage effects generated by either loss or gain of a chromosome segment were used to identify chromosome regions associated with morphological and quantitative characters in maize (Zea mays L.). Using B-A translocation stocks introgressed into a B73Ht background, a chromosome arm dosage series in a Mo17Ht x B73Ht F1 hybrid background was created for 18 of the 20 chromosome arms. The dosage series was then evaluated for 12 quantitatively inherited characters to associate specific phenotypic changes in a trait with a specific chromosome arm. Not only did our results show the familiar aneuploid syndrome phenomenon, but differential dosage effects among particular chromosome arms were demonstrated. All the quantitative traits measured and all the chromosome arms examined in this study were responsive to changes in chromosome arm dosage. The possible bases behind those differences and their utility in identifying quantitative trait loci, as well as the genetic relationships among the group of quantitatively inherited characters studied, are considered. Key words : corn, chromosome arm, B-A translocations, dosage analysis.

Effects of variation in porcine MYOD1 gene on muscle fiber characteristics, lean meat production, and meat quality traits

Three single nucleotide polymorphisms (SNPs) in the porcine MYOD1 gene were used for association analysis and haplotype construction to evaluate the effects of their substitution. Four hundred and three pigs of Yorkshire and Berkshire breeds were used. The mRNA expression levels of MYOD1 were examined. The g.489C>T and g.1264C>A SNPs were significantly associated with several muscle fiber characteristics, the loin eye area, and lightness. Particularly, animals having hetero-genotypes of both sites showed good performance both in lean meat production and meat quality traits. The results of haplotype substitution were similar to the associations of individual SNPs. Moreover, the 2 SNPs had significant effects on mRNA expression. Therefore, the g.489C>T and g.1264C>A SNPs in MYOD1 may be meaningful DNA markers that can be used for improving important porcine economic traits.

Making the hospital safer for older adult patients: a focus on the indwelling urinary catheter

The needs of hospitalized geriatric patients differ from the needs of hospitalized younger adults. In an attempt to improve systems of care for the older adult, the Centers for Medicare and Medicaid Services classified urinary tract infections related to the use of indwelling urinary catheters (IUC) as one of eight "never events." The insertion of an IUC is a commonly performed procedure that can cause an array of iatrogenic complications. In addition, the placement of an IUC without medical indication is a risk factor for prolonged hospitalization and inpatient mortality. Foley catheterization has been documented as a culprit in urosepsis and as being associated with geriatric syndromes such as delirium and functional impairment. This article will discuss the indications for the IUC, the complications that can occur because of the IUC, and comment on the Kaiser Permanente Southern California Region's efforts to minimize the unnecessary use of the IUC. Thoughtful and judicious use of the IUC, such as minimizing the use of urinary catheterization, either by not inserting an IUC or by removing it as soon as it is no longer needed, will most likely reduce inpatient morbidity and improve the health of the hospitalized older adult.

A longitudinal serological survey of parvovirus infection in dogs

Serum samples collected from dogs routinely presented at a clinic between June 1974 and October 1980 were tested for the presence of haemagglutination inhibition (HI) titres to canine parvovirus. The first positive titre (>1:320) was demonstrated in serum collected in October 1979. The first confirmed clinical case of canine parvovirus enteritis was diagnosed by the authors in July 1979. In addition, between 1st December 1980 and 1st March 1981, serum samples were collected from 106 healthy dogs which were presented for canine parvovirus vaccination for the first time. Twenty-four dogs (approx. 23%) showed HI titres >1:320 indicating probable previous canine parvovirus infection. Therefore approx. 80% of dogs in the clinic area were at risk at that time and vaccination should have protected them from infection.

Pharmacokinetics of oral doxycycline and concentrations in body fluids and bronchoalveolar cells of foals

The objective of this study was to determine the disposition of orally administered doxycycline in foals. Six healthy 4- to 8-week-old foals were used. Doxycycline was administered to each foal via the intragastric (IG) route at dosages of 10 and 20 mg/kg, in a cross-over design. After the first 10 mg/kg dose, five additional doses were administered at 12-h intervals. A microbiological assay was used to measure doxycycline activity in serum, urine, peritoneal fluid, synovial fluid, cerebrospinal (CSF), pulmonary epithelial lining fluid (PELF), and bronchoalveolar (BAL) cells. Following administration at 10 mg/kg, mean+/-SD time to peak serum doxycycline activity (tmax) was 3.0+/-1.2 h, maximum serum activity (Cmax) was 2.54+/-0.27 microg/mL, and terminal half-life (t1/2) was 8.5+/-2.8 h. Administration at a dose of 20 mg/kg resulted in a significantly longer tmax (5.5+/-1.8 h) as well as a tendency toward higher Cmax (2.89+/-0.33 microg/mL) and longer t1/2 (11.9+/-2.6 h). After multiple IG doses, doxycycline activity in CSF was significantly lower than concurrent serum activity, whereas peritoneal fluid, synovial fluid, and BAL cell doxycycline activity was similar to concurrent serum activity. Doxycycline activity in urine and PELF was significantly higher than that found at other sites. Oral administration at a dosage of 10 mg/kg every 12 h would maintain serum, PELF, and BAL cell activity above the minimum inhibitory concentrations of Rhodococcus equi, beta-hemolytic streptococci, and other susceptible bacterial pathogens for the entire dosing interval.

Pulmonary disposition of erythromycin, azithromycin, and clarithromycin in foals

The objectives of the present study were to determine and compare the pulmonary disposition of azithromycin, clarithromycin, and erythromycin in foals. A single dose (10 mg/kg) of azithromycin, clarithromycin, or erythromycin was administered intragastrically to six healthy 1- to 3-month-old foals using an orthogonal design. Activity of the drugs was measured in serum, pulmonary epithelial lining fluid (PELF), and bronchoalveolar lavage (BAL) cells by use of a microbiologic assay. Peak drug activity in PELF was significantly higher in foals treated with clarithromycin (48.96+/-13.26 microg/mL) than in foals treated with azithromycin (10.00+/-7.46 microg/mL). Quantifiable erythromycin activity in PELF was only found in two of six foals. Peak drug activity in BAL cells was not significantly different between azithromycin (49.92+/-26.94 microg/mL) and clarithromycin (74.20+/-45.80 microg/mL) but activity for both drugs was significantly higher than that of erythromycin (1.02+/-1.11 microg/mL). Terminal half-life of azithromycin in serum (25.7+/-15.4 h), PELF (34.8+/-30.9 h), and BAL cells (54.4+/-17.5 h) was significantly longer than that of both clarithromycin and erythromycin. Peak azithromycin and clarithromycin activity was significantly higher in BAL cells, followed by PELF, and serum. In contrast, peak erythromycin activity in BAL cells was not significantly different from that of serum.

The Impact of HER-2 Status on Local Recurrence in Women with Stage I?II Breast Cancer Treated with Breast-Conserving Therapy

This study was undertaken to determine whether overexpression of the oncogene HER-2 is associated with an increase in local recurrence in women with early stage breast cancer treated with breast-conserving therapy (BCT). A retrospective review of the medical records of all women treated with stage I-II invasive breast cancer from 1991 through 2001 was performed. Of 596 eligible patients treated in that time period, immunohistochemical testing for HER-2 expression was performed in 352 patients (59%): 266 patients (76%) were HER-2 negative and 86 patients (24%) were HER-2 positive. Median follow-up was 5.4 years. The patient characteristics for the two groups were compared for age, pathologic T and N stage, number of positive nodes, estrogen receptor (ER) and progesterone receptor (PR) status, radiation treatment, and use of hormonal therapy or chemotherapy. There were no significant differences in any of these parameters between the two groups (all p > or = 0.10). Local recurrence at 5 years was 2% in the HER-2-negative group and 0% in the HER-2-positive group (p = 0.15). There was no difference in local recurrence after BCT between HER-2-positive and negative breast cancers at 5 years. Therefore HER-2 overexpression does not appear to be a contraindication to BCT.

Induction of MMP-13 expression by soluble human glucocorticoid-induced tumor necrosis factor receptor in fibroblast-like synovial cells

OBJECTIVE

We tested the hypothesis that human glucocorticoid-induced tumor necrosis factor receptor (hGITR/TR11) expressed on the surface of activated CD4(+) T cells is responsible for up-regulating the production of matrix metalloproteinase (MMP)-13 by fibroblast-like synoviocytes (FLSs).

METHODS

The level of MMP-13 was measured by Western blot and reverse transcriptase polymerase chain reaction (RT-PCR). Expressions of hGITR ligand (hGITRL) on the surface of FLSs and hGITR on the surface of human CD4(+) T cells were analyzed by flow cytometry and RT-PCR. Neutralizing antibodies (Abs) were used to block hGITRL and hGITR on the surface of FLSs and human CD4(+) T cells, respectively. Human CD4(+) T cells were cocultured with FLSs to facilitate interaction between hGITR on CD4(+) T cells and hGITRL on FLSs.

RESULTS

Soluble hGITR (shGITR) stimulated FLSs to produce MMP-13, and blockade of hGITRL reduced this effect. Direct contact between activated CD4(+) T and FLSs also induced the production of MMP-13, and neutralization of hGITR on activated CD4(+) T cells during coculture decreased the amount of MMP-13 produced by FLSs.

CONCLUSION

shGITR stimulated FLSs to produce MMP-13 via a signal through hGITRL. Direct contact between activated CD4(+) T cells and FLSs facilitated hGITR-hGITRL interaction, and resulted in inducing MMP-13. This effect may increase tissue destruction in chronic inflammation such as rheumatoid arthritis (RA).

Wheat curl mite (Acari: Eriophyidae) dispersal and its relationship with kernel red streaking in maize

Wheat curl mites, Aceria tosichella Keifer, dispersing from wheat (Triticum spp.) to nearby corn (Zea mays L.) fields play a role in the development of kernel red streaking in corn. These studies were undertaken to verify the relationship of wheat curl mite to kernel red streaking, to determine whether wheat is the main source of curl mites dispersing into corn and to determine whether planting corn in temporal or spatial isolation of wheat is a valid management strategy. These studies were conducted on farm fields using sticky traps to monitor mites, followed by sampling mature grain for kernel streaking in southwestern Ontario from 1999 to 2002. The dominant source mites were winter wheat. Mite dispersal occurred during the first 3 wk of winter wheat maturation after the wheat had reached Zadoks stage 87. Mite dispersal corresponded to prevailing winds in the area with the lowest number of mites and the lowest severity of kernel red streaking occurring 60 m from wheat fields planted to the north, south, and east of cornfields and 90 m from wheat fields planted to the west of cornfields. The severity of kernel red streaking was positively correlated with the density of wheat curl mites in corn; however, the correlation was weak and kernel red streaking was still high in many cornfields when few or no mites were present. These findings suggest that wheat curl mite migration into corn is not entirely predictive of the incidence and severity of kernel red streaking.

Cilia-associated respiratory bacillus infection in rats in New Zealand

AIMS

To demonstrate cilia-associated respiratory (CAR) bacillus associated with chronic pneumonia in wild and pet rats in New Zealand.

METHODS

A range of tissues from 4 rats were examined grossly and by light microscopy and affected lungs were examined by transmission electron microscopy.

RESULTS

All 4 rats had moderate to severe cranioventral bronchopneumonia with bronchiectasis and large numbers of argentophilic bacteria resembling CAR bacillus, intimately associated with the bronchial epithelium.

CONCLUSIONS

CAR bacillus infection should be considered as a differential diagnosis for pneumonia in rats in New Zealand.

Blockade of 4-1BB (CD137)/4-1BB ligand interactions increases allograft survival

We investigated the role of 4-1BB, a T cell co-stimulatory molecule, in alloimmune responses. In vivo mixed lymphocyte reactions showed that 4-1BB was preferentially expressed on actively dividing CD4(+) and CD8(+) T cells. Furthermore, following alloantigen challenge, the draining lymph nodes contained subpopulations of 4-1BB-expressing CD4(+) and CD8(+) T cells. 4-1BB-deficient C57BL/6 mice showed a delayed rejection of cardiac transplants mismatched for the major histocompatibility complex. Longer transplant survival was induced by blockade of 4-1BB/4-1BB ligand (4-1BBL) interactions using an anti-4-1BBL monoclonal antibody. Histological analysis showed that prolonged transplant survival in the 4-1BB-deficient and anti-4-1BBL-treated mice correlated with reduced lymphocytic infiltration and vasculitis in the donor heart tissue. Taken together, our data suggest that blockade of 4-1BB/4-1BBL interactions inhibited the expansion of alloreactive T cells and reduced CTL activity against host alloantigen, which in turn resulted in the prolongation of allograft survival. Blockade of the 4-1BB co-stimulatory pathway may be useful for preventing allograft rejection.

Inactivation of the mitotic checkpoint as a determinant of the efficacy of microtubule-targeted drugs in killing human cancer cells

Drugs that disrupt microtubule dynamics include some of the most important of cancer chemotherapies. While these drugs, which include paclitaxel (Taxol), are known to invoke the mitotic checkpoint, the factors that determine cancer cell killing remain incompletely characterized. Cells that are relatively resistant to killing by these drugs block robustly in mitosis, whereas cells sensitive to killing block only transiently in mitosis before undergoing nuclear fragmentation and death. Passage through mitosis was an absolute requirement of drug-induced death, because death was markedly reduced in cells blocked at both G1-S and G2. Cell killing was at least in part linked to the absence or inactivation of BubR1, a kinetochore-associated phosphoprotein that mediates the mitotic checkpoint. Sensitivity to paclitaxel correlated with decreased BubR1 protein expression in human cancer cell lines, including those derived from breast and ovarian cancers. Silencing of BubR1 via RNA interference inactivated the mitotic checkpoint in drug-resistant cells, and reversed resistance to paclitaxel and nocodazole. Together, these results suggest that the mitotic checkpoint is an important determinant of the efficacy of microtubule-targeting drugs in killing cancer cells, potentially providing novel targets for increasing treatment efficacy.

Inactivation of the mitotic checkpoint as a determinant of the efficacy of microtubule-targeted drugs in killing human cancer cells

Drugs that disrupt microtubule dynamics include some of the most important of cancer chemotherapies. While these drugs, which include paclitaxel (Taxol), are known to invoke the mitotic checkpoint, the factors that determine cancer cell killing remain incompletely characterized. Cells that are relatively resistant to killing by these drugs block robustly in mitosis, whereas cells sensitive to killing block only transiently in mitosis before undergoing nuclear fragmentation and death. Passage through mitosis was an absolute requirement of drug-induced death, because death was markedly reduced in cells blocked at both G(1)-S and G(2). Cell killing was at least in part linked to the absence or inactivation of BubR1, a kinetochore-associated phosphoprotein that mediates the mitotic checkpoint. Sensitivity to paclitaxel correlated with decreased BubR1 protein expression in human cancer cell lines, including those derived from breast and ovarian cancers. Silencing of BubR1 via RNA interference inactivated the mitotic checkpoint in drug-resistant cells, and reversed resistance to paclitaxel and nocodazole. Together, these results suggest that the mitotic checkpoint is an important determinant of the efficacy of microtubule-targeting drugs in killing cancer cells, potentially providing novel targets for increasing treatment efficacy.

Linker-assisted immunoassay and liquid chromatography/mass spectrometry for the analysis of glyphosate

A novel, sensitive, linker-assisted enzyme-linked immunosorbent assay (L'ELISA) was compared to on-line solid-phase extraction (SPE) with high-performance liquid chromatography/mass spectrometry (HPLC/MS) for the analysis of glyphosate in surface water and groundwater samples. The L'ELISA used succinic anhydride to derivatize glyphosate, which mimics the epitotic attachment of glyphosate to horseradish peroxidase hapten. Thus, L'ELISA recognized the derivatized glyphosate more effectively (detection limit of 0.1 microg/L) and with increased sensitivity (10-100 times) over conventional ELISA and showed the potential for other applications. The precision and accuracy of L'ELISA then was compared with on-line SPE/HPLC/MS, which detected glyphosate and its degradate derivatized with 9-fluorenylmethyl chloroformate using negative-ion electrospray (detection limit 0.1 microg/ L, relative standard deviation +/- 15%). Derivatization efficiency and matrix effects were minimized by adding an isotope-labeled glyphosate (2-13C15N). The accuracy of L'EUSA gave a false positive rate of 18% between 0.1 and 1.0 microg/L and a false positive rate of only 1% above 1.0 microg/L The relative standard deviation was +/- 20%. The correlation of L'ELISA and HPLC/MS for 66 surface water and groundwater samples was 0.97 with a slope of 1.28, with many detections of glyphosate and its degradate in surface water but not in groundwater.

Unique T cell effector functions elicited by Plasmodium falciparum epitopes in malaria-exposed Africans tested by three T cell assays

Natural immunity to malaria is characterized by low level CD4 T cell reactivity detected by either lymphoproliferation or IFN-gamma secretion. Here we show a doubling in the detection rate of responders to the carboxyl terminus of circumsporozoite protein (CS) of Plasmodium falciparum by employing three T cell assays simultaneously: rapid IFN-gamma secretion (ex vivo ELISPOT), IFN-gamma secretion after reactivation of memory T cells and expansion in vitro (cultured ELISPOT), and lymphoproliferation. Remarkably, for no individual peptide did a positive response for one T cell effector function correlate with any other. Thus these CS epitopes elicited unique T cell response patterns in malaria-exposed donors. Novel or important epitope responses may therefore be missed if only one T cell assay is employed. A borderline correlation was found between anti-CS Ab levels and proliferative responses, but no correlation was found with ex vivo or cultured IFN-gamma responses. This suggested that the proliferating population, but not the IFN-gamma-secreting cells, contained cells that provide help for Ab production. The data suggest that natural immunity to malaria is a complex function of T cell subgroups with different effector functions and has important implications for future studies of natural T cell immunity.

Management of complex implant aesthetics: ensuring restorative design continuity with a comprehensive outcome-based strategy

Since implant therapy must be dictated by prosthetic requirements, a protocol for the comprehensive and continuous integration of the restorative blueprint through the entire treatment planning and clinical execution phases is mandatory. This article demonstrates a systematic approach where the establishment of a final restorative treatment objective is incorporated into the diagnosis and subsequently integrated through every phase of clinical execution. Design continuity is ensured, and multidisciplinary cohesiveness is enhanced by providing clearly defined treatment objectives to every member of the clinical team.

The biological basis of epistasis between quantitative trait loci for flavone and 3-deoxyanthocyanin synthesis in maize (Zea mays L.)

A major weakness in our understanding of the genetic basis of complex traits has been that of defining the extent and biological basis of epistasis. Our research group has been studying the genetic control of the accumulation of maysin, a C-glycosyl flavone, in maize, Zea mays (L.), silks. Previously, we demonstrated the importance of the p1 locus as a QTL for maysin synthesis. The p1 locus often exhibits significant epistatic interactions with other loci. We developed a mapping population, (W23al x GT119)F2, specifically designed to test whether genes in an intersecting pathway might be detected as QTLs for maysin synthesis and result in epistatic interaction effects. The a1 gene is not required for the synthesis of flavones but is required for the synthesis of 3-deoxyanthocyanins, an intersecting pathway, in maize silks. The p1 locus (P < 0.0001) was a QTL for both flavones and 3-deoxyanthocyanins. The a1 locus was also highly significant (P < 0.0001) for both traits, as was the p1 x a1 epistatic interaction (P < 0.0001). Our results demonstrate that altering the flux of biochemical intermediates between pathways may be the biological basis of major QTL effects and epistatic interactions.

Young children and the say/mean distinction: verbatim and paraphrase recognition in narrative and nursery rhyme contexts

Children's ability to distinguish between the text, what was said, and the intentional structure, what was meant, was interrogated by means of verbatim and paraphrase questions in two types of discourse, narratives and nursery rhymes. Three- to seven-year-olds participated (n = 119, mean age 5.1). There was an interaction between the type of discourse and the younger children's ability to separate wording from intentional structure. In the narrative form they had difficulty rejecting true paraphrases when asked to focus on wording, while in the nursery rhyme form the difficulty was accepting a true paraphrase when asked to focus on intention.

Structural and functional alterations of the peritoneum after prolonged exposure to dialysis solutions: role of aminoguanidine

OBJECTIVE

The effect of long-term use of high glucose dialysate on peritoneal structure and function, and its relation with accumulation of advanced glycosylation end-product (AGE) in the peritoneum was investigated in this study.

METHODS

Dialysates with 4.25% glucose were injected into the peritoneal cavity of normal rats for 12 weeks without (PD, n = 7) and with (1 g/L, PD+AG, n = 7) aminoguanidine in their drinking water. Rats not having intraperitoneal (IP) injection served as control (n = 9). After 12 weeks of IP injection, a 2-hour peritoneal equilibration test (PET) was performed using 30 mL 4.25% glucose dialysate. Intraperitoneal volume (IPV), dialysate-to-plasma urea ratio at 2 hours (D/P2), the ratio of dialysate glucose at 2 hours to initial dialysate glucose (D2/D0), and the peritoneal fluid absorption rate (Qa) were evaluated. After the PET, samples of the parietal peritoneum were taken for hematoxylin and eosin (H&E) staining and immunohistochemical staining for AGE.

RESULTS

The IPV and D2/D0 glucose were significantly lower and Qa and D2/P2 urea significantly higher in the PD group than in the control group. Aminoguanidine reversed in part the changes in IPV and D2/P2 urea in the PD group; it had no effect on Qa and D2/D0 glucose. The H&E staining showed a linear mesothelial lining with negligible cells and capillaries in the narrow submesothelial space in the control group. Mesothelial denudation and submesothelial infiltration of monocytes and capillary formation were observed in the PD group. Mesothelial denudation was relatively intact in the PD+AG group compared with the PD group. Submesothelial monocyte infiltration and capillary formation in the PD+AG group were not as prominent as in the PD group. Positive AGE staining was found in the submesothelial space, vascular walls, and endomysium in the PD group, while it was markedly attenuated in PD+AG group and negligible in the control group.

CONCLUSION

Long-term use of high glucose solutions induced peritoneal AGE accumulation and mesothelial denudation, and increased peritoneal permeability and peritoneal fluid absorption rate. Inhibition of peritoneal AGE accumulation prevented those functional and structural damages to the peritoneum.

Identification of frequently recognized dimorphic T-cell epitopes in plasmodium falciparum merozoite surface protein-1 in West and East Africans: lack of correlation of immune recognition and allelic prevalence

The merozoite surface protein-1 (MSP1) is the most studied malaria blood-stage vaccine candidate. Lymphokines such as interferon gamma (IFN-gamma) and interleukin 4 (IL-4) may mediate blood-stage specific protection. Here we identify Plasmodiumfalciparum MSP1 T-cell epitopes capable of rapid induction of IFN-gamma and/or IL-4 from peripheral blood mononuclear cells of East and West African donors. Both allelic forms of these novel MSP1 T-cell epitopes were stimulatory. An unusually high numbers of Gambian responders (> 80%) to these epitopes were observed, suggesting that MSPI reactivity may have been underestimated previously in this population. Surprisingly, IFN-gamma responses to allelic T-cell epitopes failed to correlate with differential antigenic exposure in The Gambia compared to Kenya. These results suggest an unexpected level of immunoregulation of IFN-gamma response with variable allelic T-cell reactivity independent of the level of antigenic exposure. Further analysis of the mechanisms determining this response pattern may be required if vaccines are to overcome this allelic reactivity bias in malaria-exposed populations.

Bearing illness and injury

This qualitative study examined how individuals with catastrophic illness and injury managed their personal and social world. The 28 males and females had endured their chronic conditions from 3 to 25 years prior to the study. Participants were individually interviewed. Responses were analyzed using grounded theory methods. Individuals with catastrophic illness and injury experienced three phases in bearing their situation: finding out, facing reality, and managing reality. Individuals did not progress through stages as has been argued by stage theorists. Rather, the phases flowed together and were reexperienced continuously. Individuals employed three strategies--protecting, modifying, and boosting--in all of the phases to help them endure their circumstances.

Stabilization of molecular atoms

We demonstrate the possibility of stabilizing the motion of ion-pair states through the use of external electric and magnetic fields. In conjunction with the Coulomb force, these fields can be engineered so as to lead to the creation of outer equilibrium points which can support non-spreading coherent wavepackets and long-lived states. Specific application is made to the H(+)-H- ion pair, recently investigated using threshold ion-pair production spectroscopy (TIPPS).

Achieving aesthetic excellence through an outcome-based restorative treatment rationale

The conceptual basis of restorative-driven implant dentistry is well established among clinicians. Its implementation includes the development of a prosthetic blue-print that will serve as a guide throughout therapy. While these concepts may be applied to prosthetic dentistry in general, their benefits are most compelling in the treatment of the aesthetic zone. This article demonstrates a systematic multidimensional approach for the establishment and incorporation of definitive aesthetic objectives throughout the diagnostic, adjunctive, and restorative treatment phases.

Transitional custom abutments: optimizing aesthetic treatment in implant-supported restorations

As the discipline of implant prosthodontics continues to evolve, additional emphasis has been focused on the role of adequate emergence profiles and peri-implant soft tissue contours. Despite the development of anatomically shaped healing abutments, currently advocated techniques exhibit clinical limitations. This article introduces the transitional custom abutment technique as a method of manipulating the supra-implant soft tissue contours so that optimal emergence profiles and increased restorative flexibility can be achieved in the treatment of patients with compromised fixture angulation.

Purification of chitinolytic protein from Rehmannia glutinosa showing N-terminal amino acid sequence similarity to thaumatin-like proteins

We have purified a 21-kDa protein, designated as P1, from Rehmannia glutinosa to homogeneity by ammonium sulfate precipitation, anion exchange chromatography, hydrophobic interaction chromatography, and preparative native PAGE. The purified P1 had chitin degradation activity. The N-terminal amino acid sequence of P1 indicated that it is very similar to those of thaumatin and other reported thaumatin-like proteins.

Interleukin 10-mediated immunosuppression by a variant CD4 T cell epitope of Plasmodium falciparum

The immunodominant CD4 T cell epitope region, Th2R, of the circumsporozoite protein of Plasmodium falciparum is highly polymorphic. Such variation might be utilized by the parasite to escape from or interfere with CD4 T cell effector functions. Here, we show that costimulation with naturally occurring altered peptide ligands (APL) can induce a rapid change from IFNgamma production to the immunosuppressive mediator interleukin 10 (IL-10). This mechanism may contribute to the low levels of T cell responses observed to this pathogen in malaria-endemic areas.

Broadly distributed T cell reactivity, with no immunodominant loci, to the pre-erythrocytic antigen thrombospondin-related adhesive protein of Plasmodium falciparum in West Africans

Protective immunity to malaria has been achieved in human volunteers utilizing the pre-erythrocytic Plasmodium falciparum antigen, the circumsporozoite protein (CS). However, T cell reactivity to CS is focused on several highly polymorphic T cell epitope regions, potentially limiting the efficacy of any vaccine to specific malaria strains. Another important pre-erythrocytic malaria antigen, the thrombospondin-related adhesive protein (TRAP), can induce protection in animal models of malaria, but knowledge of human T cell responses is limited to the identification of CD8 T cell epitopes, with no CD4 epitopes identified to date. This comprehensive study assessed reactivity to overlapping peptides spanning almost the whole of P. falciparum TRAP (PfTRAP), as well as peptides selected on the basis of HLA class II-binding motifs. A total of 50 naturally exposed Gambian adults were assessed to define 26 T cell epitopes in PfTRAP capable of inducing rapid IFN-gamma or IL-4 production, as assessed by enzyme-linked immunospot assays. In contrast to the CS protein, this reactivity was broadly distributed along the length of TRAP. Moreover, of the 26 epitopes identified, 10 were found to be conserved in West Africa.