Postoperative pulmonary complications following major head and neck cancer surgery

The primary aim of this observational study was to describe the incidence of postoperative pulmonary complications (PPCs) in 60 consecutive, surgically treated head and neck cancer patients requiring free flap reconstruction and tracheostomy, using both a prospective and a retrospective outcome measure. Secondary aims were to identify risk factors for PPC development, explore the effects of PPC on outcomes, and describe the provision of postoperative physiotherapy in this population. Postoperative pulmonary complications occurred in nine (15%) patients based on the Melbourne Group Scale and 27 (45%) patients based on Health Information Service coding data. The occurrence of a PPC was not statistically correlated with age, smoking history, comorbidities, operative time, or type of resection or free flap. Patients who developed a PPC, compared to those who did not, had a higher preoperative body mass index (P=0.022) and were more likely to be sat out of bed earlier post-surgery (P=0.038). Overall, patients required a median of 9.0 (interquartile range 7.0-11.0) physiotherapy sessions. Patients developing a PPC required significantly more physiotherapy sessions (P=0.007) and additional days of supplemental oxygen (P=0.022) as compared to those without a PPC, despite a similar hospital length of stay. In future, targeted physiotherapy interventions may reduce PPCs in this population.

Imperforate Hymen and Vaginal Atresia and their Associated Anomalies

The presenting features and associated abnormalities of imperforate hymen and vaginal atresia were studied in 24 girls under the age of 16 years. Hydrocolpos or hydrometrocolpos occurred in 8 infants, 13 older girls developed haematocolpos, but 3 of the girls had no distension of the genital tract. Seven of the older girls were diagnosed as having appendicitis. Anorectal anomalies were present in 9 of the children. Intravenous pyelography was performed on 16 girls and was normal in only one. Urinary tract investigations are indicated in all girls with vaginal outlet obstruction, and the vaginal orifice should be inspected in all girls with anorectal abnormalities.

Cerebrospinal fluid markers including trefoil factor 3 are associated with neurodegeneration in amyloid-positive individuals

We aimed to identify cerebrospinal fluid (CSF) biomarkers associated with neurodegeneration in individuals with and without CSF evidence of Alzheimer pathology. We investigated 287 Alzheimer's Disease Neuroimaging Initiative (ADNI) subjects (age=74.9±6.9; 22/48/30% with Alzheimer's disease/mild cognitive impairment/controls) with CSF multiplex analyte data and serial volumetric MRI. We calculated brain and hippocampal atrophy rates, ventricular expansion and Mini Mental State Examination decline. We used false discovery rate corrected regression analyses to assess associations between CSF variables and atrophy rates in individuals with and without amyloid pathology, adjusting in stages for tau, baseline volume, p-tau, age, sex, ApoE4 status and diagnosis. Analytes showing statistically significant independent relationships were entered into reverse stepwise analyses. Adjusting for tau, baseline volume, p-tau, age, sex and ApoE4, 4/83 analytes were significantly independently associated with brain atrophy rate, 1/83 with ventricular expansion and 2/83 with hippocampal atrophy. The strongest CSF predictor for the three atrophy measures was low trefoil factor 3 (TFF3). High cystatin C (CysC) was associated with higher whole brain atrophy and hippocampal atrophy rates. Lower levels of vascular endothelial growth factor and chromogranin A (CrA) were associated with higher whole brain atrophy. In exploratory reverse stepwise analyses, lower TFF3 was associated with higher rates of whole brain, hippocampal atrophy and ventricular expansion. Lower levels of CrA were associated with higher whole brain atrophy rate. The relationship between low TFF3 and increased hippocampal atrophy rate remained after adjustment for diagnosis. We identified a series of CSF markers that are independently associated with rate of neurodegeneration in amyloid-positive individuals. TFF3, a substrate for NOTCH processing may be an important biomarker of neurodegeneration across the Alzheimer spectrum.

Anxiety is related to Alzheimer cerebrospinal fluid markers in subjects with mild cognitive impairment

BACKGROUND

Anxiety, apathy and depression are common in subjects with mild cognitive impairment (MCI) and may herald Alzheimer's disease (AD). We investigated whether these symptoms correlated with cerebrospinal fluid (CSF) markers for AD in subjects with MCI. Method Subjects with MCI (n=268) were selected from the 'Development of screening guidelines and criteria for pre-dementia Alzheimer's disease' (DESCRIPA) and Alzheimer's Disease Neuroimaging Initiative (ADNI) studies. We measured amyloid β(1-42) protein (Aβ42) and total tau (t-tau) in CSF. Neuropsychiatric symptoms were measured with the Neuropsychiatric Inventory.

RESULTS

Depressive symptoms were reported by 55 subjects (21%), anxiety by 35 subjects (13%) and apathy by 49 subjects (18%). The presence of anxiety was associated with abnormal CSF Aβ42 [odds ratio (OR) 2.3, 95% confidence interval (CI) 1.6-3.3] and t-tau (OR 2.6, 95% CI 1.9-3.6) concentrations and with the combination of abnormal concentrations of both Aβ42 and t-tau (OR 3.1, 95% CI 2.0-4.7). The presence of agitation and irritability was associated with abnormal concentrations of Aβ42 (agitation: OR 1.6, 95% CI 1.1-2.3; irritability: OR 2.2, 95% CI 1.5-3.3). Symptoms of depression and apathy were not related to any of the CSF markers.

CONCLUSIONS

In subjects with MCI, symptoms of anxiety, agitation and irritability may reflect underlying AD pathology, whereas symptoms of depression and apathy do not.

Plasma biomarkers of depressive symptoms in older adults

The pathophysiology of negative affect states in older adults is complex, and a host of central nervous system and peripheral systemic mechanisms may play primary or contributing roles. We conducted an unbiased analysis of 146 plasma analytes in a multiplex biochemical biomarker study in relation to number of depressive symptoms endorsed by 566 participants in the Alzheimer's Disease Neuroimaging Initiative (ADNI) at their baseline and 1-year assessments. Analytes that were most highly associated with depressive symptoms included hepatocyte growth factor, insulin polypeptides, pregnancy-associated plasma protein-A and vascular endothelial growth factor. Separate regression models assessed contributions of past history of psychiatric illness, antidepressant or other psychotropic medicine, apolipoprotein E genotype, body mass index, serum glucose and cerebrospinal fluid (CSF) τ and amyloid levels, and none of these values significantly attenuated the main effects of the candidate analyte levels for depressive symptoms score. Ensemble machine learning with Random Forests found good accuracy (~80%) in classifying groups with and without depressive symptoms. These data begin to identify biochemical biomarkers of depressive symptoms in older adults that may be useful in investigations of pathophysiological mechanisms of depression in aging and neurodegenerative dementias and as targets of novel treatment approaches.

Pharmacokinetic targeting of i.v. BU with fludarabine as conditioning before hematopoietic cell transplant: the effect of first-dose area under the concentration time curve on transplant-related outcomes

We used pharmacokinetic (PK) targeting of BU in 145 consecutive patients treated with fludarabine and i.v. BU. BU was given once daily at 130 mg/m(2) per day on days 1 and 2; doses for days 3 and 4 were adjusted in 92 patients (63%) to an average daily area under the concentration-time curve (AUC) of 5300 μM/min. In the remaining 53 patients, the first-dose AUC was within the target range and no dosing adjustments were required. First-dose AUC, maximum concentration and clearance were not correlated with age, race, ethnicity, performance status, or hematopoietic cell transplant comorbidity index. Women had higher clearance than men (median 2.9 vs 2.5 mL/min/kg; P=0.001). BU toxicities were not associated with first-dose AUC or any other PK parameter measured. First-dose BU AUC was not associated with non-relapse mortality (NRM) or survival, but higher AUC was predictive of relapse. We did not find an increased risk of toxicity or NRM in patients with high first-dose AUC presumably because of the dose adjustment. We conclude that PK targeting of BU as described here provides a simple, safe and effective method of delivering high BU doses before transplantation in a wide variety of patients.

Genome-wide association study of CSF biomarkers Abeta1-42, t-tau, and p-tau181p in the ADNI cohort

OBJECTIVES

CSF levels of Aβ1-42, t-tau, and p-tau181p are potential early diagnostic markers for probable Alzheimer disease (AD). The influence of genetic variation on these markers has been investigated for candidate genes but not on a genome-wide basis. We report a genome-wide association study (GWAS) of CSF biomarkers (Aβ1-42, t-tau, p-tau181p, p-tau181p/Aβ1-42, and t-tau/Aβ1-42).

METHODS

A total of 374 non-Hispanic Caucasian participants in the Alzheimer's Disease Neuroimaging Initiative cohort with quality-controlled CSF and genotype data were included in this analysis. The main effect of single nucleotide polymorphisms (SNPs) under an additive genetic model was assessed on each of 5 CSF biomarkers. The p values of all SNPs for each CSF biomarker were adjusted for multiple comparisons by the Bonferroni method. We focused on SNPs with corrected p<0.01 (uncorrected p<3.10×10(-8)) and secondarily examined SNPs with uncorrected p values less than 10(-5) to identify potential candidates.

RESULTS

Four SNPs in the regions of the APOE, LOC100129500, TOMM40, and EPC2 genes reached genome-wide significance for associations with one or more CSF biomarkers. SNPs in CCDC134, ABCG2, SREBF2, and NFATC4, although not reaching genome-wide significance, were identified as potential candidates.

CONCLUSIONS

In addition to known candidate genes, APOE, TOMM40, and one hypothetical gene LOC100129500 partially overlapping APOE; one novel gene, EPC2, and several other interesting genes were associated with CSF biomarkers that are related to AD. These findings, especially the new EPC2 results, require replication in independent cohorts.

Novel CSF biomarkers for frontotemporal lobar degenerations

OBJECTIVE

To identify antemortem CSF diagnostic biomarkers that can potentially distinguish between the 2 main causes of frontotemporal lobar degeneration (FTLD), i.e., FTLD with TDP-43 pathology (FTLD-TDP) and FTLD with tau pathology (FTLD-tau).

METHODS

CSF samples were collected antemortem from 23 patients with FTLD with known pathology to form a autopsy cohort as part of a comparative biomarker study that additionally included 33 living cognitively normal subjects and 66 patients with autopsy-confirmed Alzheimer disease (AD). CSF samples were also collected from 80 living patients clinically diagnosed with frontotemporal dementia (FTD). Levels of 151 novel analytes were measured via a targeted multiplex panel enriched in neuropeptides, cytokines, and growth factors, along with levels of CSF biomarkers for AD.

RESULTS

CSF levels of multiple analytes differed between FTLD-TDP and FTLD-tau, including Fas, neuropeptides (agouti-related peptide and adrenocorticotropic hormone), and chemokines (IL-23, IL-17). Classification by random forest analysis achieved high sensitivity for FTLD-TDP (86%) with modest specificity (78%) in the autopsy cohort. When the classification algorithm was applied to a living FTD cohort, semantic dementia was the phenotype with the highest predicted proportion of FTLD-TDP. When living patients with behavioral variant FTD were examined in detail, those predicted to have FTLD-TDP demonstrated neuropsychological differences vs those predicted to have FTLD-tau in a pattern consistent with previously reported trends in autopsy-confirmed cases.

CONCLUSIONS

Clinical cases with FTLD-TDP and FTLD-tau pathology can be potentially identified antemortem by assaying levels of specific analytes that are well-known and readily measurable in CSF.

CSF amyloid {beta} 1-42 predicts cognitive decline in Parkinson disease

OBJECTIVE

Cognitive decline associated with Parkinson disease (PD) is common and highly disabling. Biomarkers that help identify patients at risk for cognitive decline would be useful additions to the clinical management of the disease.

METHODS

A total of 45 patients with PD were enrolled in this prospective cohort study and had at least 1 yearly longitudinal follow-up evaluation. CSF was collected at baseline and cognition was assessed at baseline and follow-up visits using the Mattis Dementia Rating Scale (DRS-2). CSF was tested for amyloid β 1-42 (Aβ(1-42)), p-tau(181p), and total tau levels using the Luminex xMAP platform. Mixed linear models were used to test for associations between baseline CSF biomarker levels and change in cognition over time.

RESULTS

Lower baseline CSF Aβ(1-42) was associated with more rapid cognitive decline. Subjects with CSF Aβ(1-42) levels ≤192 pg/mL declined an average of 5.85 (95% confidence interval 2.11-9.58, p = 0.002) points per year more rapidly on the DRS-2 than subjects above that cutoff, after adjustment for age, disease duration, and baseline cognitive status. CSF total tau and p-tau(181p) levels were not significantly associated with cognitive decline.

CONCLUSIONS

Reduced CSF Aβ(1-42) was an independent predictor of cognitive decline in patients with PD. This observation is consistent with previous research showing that Alzheimer disease pathology contributes to cognitive impairment in PD. This biomarker may provide clinically useful prognostic information, particularly if combined with other risk factors for cognitive impairment in PD.

Serial MRI and CSF biomarkers in normal aging, MCI, and AD

OBJECTIVE

To compare the annual change in MRI and CSF biomarkers in cognitively normal (CN), amnestic mild cognitive impairment (aMCI), and Alzheimer disease (AD). Comparisons were based on intergroup discrimination, correlation with concurrent cognitive/functional changes, relationships to APOE genotype, and sample sizes for clinical trials.

METHODS

We used data from the Alzheimer's Disease Neuroimaging Initiative study consisting of CN, aMCI, and AD cohorts with both baseline and 12-month follow-up CSF and MRI. The annual change in CSF (total-tau [t-tau], Abeta(1-42)) and MRI (change in ventricular volume) was obtained in 312 subjects (92 CN, 149 aMCI, 71 AD).

RESULTS

There was no significant average annual change in either CSF biomarker in any clinical group except t-tau in CN; moreover, the annual change did not differ by clinical group in pairwise comparisons. In contrast, annual increase in ventricular volume increased in the following order, AD > aMCI > CN, and differences were significant between all clinical groups in pairwise comparisons. Ventricular volume increase correlated with concurrent worsening on cognitive/functional indices in aMCI and AD whereas evidence of a similar correlation with change in CSF measures was unclear. The annual changes in MRI differed by APOE epsilon4 status overall and among aMCI while annual changes in CSF biomarkers did not. Estimated sample sizes for clinical trials are notably less for MRI than the CSF or clinical measures.

CONCLUSIONS

Unlike the CSF biomarkers evaluated, changes in serial structural MRI are correlated with concurrent change on general cognitive and functional indices in impaired subjects, track with clinical disease stage, and are influenced by APOE genotype.

Comparing predictors of conversion and decline in mild cognitive impairment

OBJECTIVE

A variety of measurements have been individually linked to decline in mild cognitive impairment (MCI), but the identification of optimal markers for predicting disease progression remains unresolved. The goal of this study was to evaluate the prognostic ability of genetic, CSF, neuroimaging, and cognitive measurements obtained in the same participants.

METHODS

APOE epsilon4 allele frequency, CSF proteins (Abeta(1-42), total tau, hyperphosphorylated tau [p-tau(181p)]), glucose metabolism (FDG-PET), hippocampal volume, and episodic memory performance were evaluated at baseline in patients with amnestic MCI (n = 85), using data from a large multisite study (Alzheimer's Disease Neuroimaging Initiative). Patients were classified as normal or abnormal on each predictor variable based on externally derived cutoffs, and then variables were evaluated as predictors of subsequent conversion to Alzheimer disease (AD) and cognitive decline (Alzheimer's Disease Assessment Scale-Cognitive Subscale) during a variable follow-up period (1.9 +/- 0.4 years).

RESULTS

Patients with MCI converted to AD at an annual rate of 17.2%. Subjects with MCI who had abnormal results on both FDG-PET and episodic memory were 11.7 times more likely to convert to AD than subjects who had normal results on both measures (p <or= 0.02). In addition, the CSF ratio p-tau(181p)/Abeta(1-42) (beta = 1.10 +/- 0.53; p = 0.04) and, marginally, FDG-PET predicted cognitive decline.

CONCLUSIONS

Baseline FDG-PET and episodic memory predict conversion to AD, whereas p-tau(181p)/Abeta(1-42) and, marginally, FDG-PET predict longitudinal cognitive decline. Complementary information provided by these biomarkers may aid in future selection of patients for clinical trials or identification of patients likely to benefit from a therapeutic intervention.

Subtypes based on cerebrospinal fluid and magnetic resonance imaging markers in normal elderly predict cognitive decline

Cerebrospinal fluid (CSF) and structural magnetic resonance imaging (MRI) show patterns of change in Alzheimer's disease (AD) that precede dementia. The Alzheimer's Disease Neuroimaging Initiative (ADNI) studied normal controls (NC), subjects with mild cognitive impairment (MCI), and subjects with AD to identify patterns of biomarkers to aid in early diagnosis and effective treatment of AD. Two hundred twenty-two NC underwent baseline MRI and clinical examination at baseline and at least one follow-up. One hundred twelve also provided CSF at baseline. Unsupervised clustering based on initial CSF and MRI measures was used to identify clusters of participants with similar profiles. Repeated measures regression modeling assessed the relationship of individual measures, and of cluster membership, to cognitive change over 3 years. Most individuals showed little cognitive change. Individual biomarkers had limited predictive value for cognitive decline, but membership in the cluster with the most extreme profile was associated with more rapid decline in ADAS-cog. Subtypes among NC based on multiple biomarkers may represent the earliest stages of subclinical cognitive decline and AD.

Alzheimer's Disease Neuroimaging Initiative (ADNI): clinical characterization

BACKGROUND

Neuroimaging measures and chemical biomarkers may be important indices of clinical progression in normal aging and mild cognitive impairment (MCI) and need to be evaluated longitudinally.

OBJECTIVE

To characterize cross-sectionally and longitudinally clinical measures in normal controls, subjects with MCI, and subjects with mild Alzheimer disease (AD) to enable the assessment of the utility of neuroimaging and chemical biomarker measures.

METHODS

A total of 819 subjects (229 cognitively normal, 398 with MCI, and 192 with AD) were enrolled at baseline and followed for 12 months using standard cognitive and functional measures typical of clinical trials.

RESULTS

The subjects with MCI were more memory impaired than the cognitively normal subjects but not as impaired as the subjects with AD. Nonmemory cognitive measures were only minimally impaired in the subjects with MCI. The subjects with MCI progressed to dementia in 12 months at a rate of 16.5% per year. Approximately 50% of the subjects with MCI were on antidementia therapies. There was minimal movement on the Alzheimer's Disease Assessment Scale-Cognitive Subscale for the normal control subjects, slight movement for the subjects with MCI of 1.1, and a modest change for the subjects with AD of 4.3. Baseline CSF measures of Abeta-42 separated the 3 groups as expected and successfully predicted the 12-month change in cognitive measures.

CONCLUSION

The Alzheimer's Disease Neuroimaging Initiative has successfully recruited cohorts of cognitively normal subjects, subjects with mild cognitive impairment (MCI), and subjects with Alzheimer disease with anticipated baseline characteristics. The 12-month progression rate of MCI was as predicted, and the CSF measures heralded progression of clinical measures over 12 months.

Relationships between biomarkers in aging and dementia

BACKGROUND

PET imaging using [(18)F]fluorodeoxyglucose (FDG) and [(11)C]Pittsburgh compound B (PIB) have been proposed as biomarkers of Alzheimer disease (AD), as have CSF measures of the 42 amino acid beta-amyloid protein (Abeta(1-42)) and total and phosphorylated tau (t-tau and p-tau). Relationships between biomarkers and with disease severity are incompletely understood.

METHODS

Ten subjects with AD, 11 control subjects, and 34 subjects with mild cognitive impairment from the Alzheimer's Disease Neuroimaging Initiative underwent clinical evaluation; CSF measurement of Abeta(1-42), t-tau, and p-tau; and PIB-PET and FDG-PET scanning. Data were analyzed using continuous regression and dichotomous outcomes with subjects classified as "positive" or "negative" for AD based on cutoffs established in patients with AD and controls from other cohorts.

RESULTS

Dichotomous categorization showed substantial agreement between PIB-PET and CSF Abeta(1-42) measures (91% agreement, kappa = 0.74), modest agreement between PIB-PET and p-tau (76% agreement, kappa = 0.50), and minimal agreement for other comparisons (kappa <0.3). Mini-Mental State Examination score was significantly correlated with FDG-PET but not with PIB-PET or CSF Abeta(1-42). Regression models adjusted for diagnosis showed that PIB-PET was significantly correlated with Abeta(1-42), t-tau, and p-tau(181p), whereas FDG-PET was correlated only with Abeta(1-42).

CONCLUSIONS

PET and CSF biomarkers of Abeta agree with one another but are not related to cognitive impairment. [(18)F]fluorodeoxyglucose-PET is modestly related to other biomarkers but is better related to cognition. Different biomarkers for Alzheimer disease provide different information from one another that is likely to be complementary.

MRI and CSF biomarkers in normal, MCI, and AD subjects: diagnostic discrimination and cognitive correlations

OBJECTIVE

To assess the correlations of both MRI and CSF biomarkers with clinical diagnosis and with cognitive performance in cognitively normal (CN) subjects and patients with amnestic mild cognitive impairment (aMCI) and Alzheimer disease (AD).

METHODS

This is a cross-sectional study with data from the Alzheimer's Disease Neuroimaging Initiative, which consists of CN subjects, subjects with aMCI, and subjects with AD with both CSF and MRI. Baseline CSF (t-tau, Abeta(1-42), and p-tau(181P)) and MRI scans were obtained in 399 subjects (109 CN, 192 aMCI, 98 AD). Structural Abnormality Index (STAND) scores, which reflect the degree of AD-like anatomic features on MRI, were computed for each subject.

RESULTS

We found no significant correlation between CSF biomarkers and cognitive scores in any of the 3 clinical groups individually. Conversely, STAND scores correlated with both Clinical Dementia Rating-sum of boxes and Mini-Mental State Examination in aMCI and AD (p < or = 0.01). While STAND and all CSF biomarkers were predictors of clinical group membership (CN, aMCI, or AD) univariately (p < 0.001), STAND was more predictive than CSF both univariately and in combined models.

CONCLUSIONS

CSF and MRI biomarkers independently contribute to intergroup diagnostic discrimination and the combination of CSF and MRI provides better prediction than either source of data alone. However, MRI provides greater power to effect cross-sectional groupwise discrimination and better correlation with general cognition and functional status cross-sectionally. We therefore conclude that although MRI and CSF provide complementary information, MRI reflects clinically defined disease stage better than the CSF biomarkers tested.

MRI and CSF biomarkers in normal, MCI, and AD subjects: predicting future clinical change

OBJECTIVE

To investigate the relationship between baseline MRI and CSF biomarkers and subsequent change in continuous measures of cognitive and functional abilities in cognitively normal (CN) subjects and patients with amnestic mild cognitive impairment (aMCI) and Alzheimer disease (AD) and to examine the ability of these biomarkers to predict time to conversion from aMCI to AD.

METHODS

Data from the Alzheimer's Disease Neuroimaging Initiative, which consists of CN, aMCI, and AD cohorts with both CSF and MRI, were used. Baseline CSF (t-tau, Abeta(1-42), and p-tau(181P)) and MRI scans were obtained in 399 subjects (109 CN, 192 aMCI, 98 AD). Structural Abnormality Index (STAND) scores, which reflect the degree of AD-like features in MRI, were computed for each subject.

RESULTS

Change on continuous measures of cognitive and functional performance was modeled as average Clinical Dementia Rating-sum of boxes and Mini-Mental State Examination scores over a 2-year period. STAND was a better predictor of subsequent cognitive/functional change than CSF biomarkers. Single-predictor Cox proportional hazard models for time to conversion from aMCI to AD showed that STAND and log (t-tau/Abeta(1-42)) were both predictive of future conversion. The age-adjusted hazard ratio for an interquartile change (95% confidence interval) of STAND was 2.6 (1.7, 4.2) and log (t-tau/Abeta(1-42)) was 2.0 (1.1, 3.4). Both MRI and CSF provided information about future cognitive change even after adjusting for baseline cognitive performance.

CONCLUSIONS

MRI and CSF provide complimentary predictive information about time to conversion from amnestic mild cognitive impairment to Alzheimer disease and combination of the 2 provides better prediction than either source alone. However, we found that MRI was a slightly better predictor of future clinical/functional decline than the CSF biomarkers tested.

Fixed- or controlled-dose mycophenolate mofetil with standard- or reduced-dose calcineurin inhibitors: the Opticept trial

Mycophenolate mofetil (MMF) was developed with cyclosporine as a fixed-dose immunosuppressant. More recent data indicate a relationship between mycophenolic acid (MPA) exposure in individuals and clinical endpoints of rejection and toxicity. This 2-year, open-label, randomized, multicenter trial compared the efficacy and safety of concentration-controlled MMF (MMF(CC)) dosing with a fixed-dose regimen in 720 kidney recipients. Patients received either (A) MMF(CC) and reduced-level calcineurin inhibitor (MMF(CC)/CNI(RL)); (B) MMF(CC) and standard-level CNI (MMF(CC)/CNI(SL)); or (C) fixed-dose MMF and CNI(SL) (MMF(FD)/CNI(SL)). Antibody induction and steroid use were according to center practice. The primary endpoint was noninferiority (alpha= 0.05) of group A versus group C for treatment failure (including biopsy-proven acute rejection [BPAR], graft loss and death) at 1 year. Although mean CNI trough levels in group A did not reach the prespecified targets, they were statistically lower than those in groups B and C (p < or = 0.01 for each comparison). BPAR rates (8.5%) were low across groups. Group A had 19% fewer treatment failures (23% vs. 28%, p = 0.18). MMF doses were highest (p < 0.05), with withdrawals for adverse events the fewest (p = 0.02), in group A. Of the 80% of subjects taking tacrolimus (Tac), those with higher MPA exposure had significantly less rejection (p < 0.001) and diarrhea correlated with Tac, but not with MPA levels. Thus, MMF(CC) with low-dose CNI resulted in outcomes not inferior to those with standard CNI exposure and MMF(FD), indicating potential utility of MMF(CC) in CNI-sparing regimens.

Fixed- or controlled-dose mycophenolate mofetil with standard- or reduced-dose calcineurin inhibitors: the Opticept trial

Mycophenolate mofetil (MMF) was developed with cyclosporine as a fixed-dose immunosuppressant. More recent data indicate a relationship between mycophenolic acid (MPA) exposure in individuals and clinical endpoints of rejection and toxicity. This 2-year, open-label, randomized, multicenter trial compared the efficacy and safety of concentration-controlled MMF (MMF(CC)) dosing with a fixed-dose regimen in 720 kidney recipients. Patients received either (A) MMF(CC) and reduced-level calcineurin inhibitor (MMF(CC)/CNI(RL)); (B) MMF(CC) and standard-level CNI (MMF(CC)/CNI(SL)); or (C) fixed-dose MMF and CNI(SL) (MMF(FD)/CNI(SL)). Antibody induction and steroid use were according to center practice. The primary endpoint was noninferiority (alpha= 0.05) of group A versus group C for treatment failure (including biopsy-proven acute rejection [BPAR], graft loss and death) at 1 year. Although mean CNI trough levels in group A did not reach the prespecified targets, they were statistically lower than those in groups B and C (p < or = 0.01 for each comparison). BPAR rates (8.5%) were low across groups. Group A had 19% fewer treatment failures (23% vs. 28%, p = 0.18). MMF doses were highest (p < 0.05), with withdrawals for adverse events the fewest (p = 0.02), in group A. Of the 80% of subjects taking tacrolimus (Tac), those with higher MPA exposure had significantly less rejection (p < 0.001) and diarrhea correlated with Tac, but not with MPA levels. Thus, MMF(CC) with low-dose CNI resulted in outcomes not inferior to those with standard CNI exposure and MMF(FD), indicating potential utility of MMF(CC) in CNI-sparing regimens.

MRI of hippocampal volume loss in early Alzheimer's disease in relation to ApoE genotype and biomarkers

Hippocampal volume change over time, measured with MRI, has huge potential as a marker for Alzheimer's disease. The objectives of this study were: (i) to test if constant and accelerated hippocampal loss can be detected in Alzheimer's disease, mild cognitive impairment and normal ageing over short periods, e.g. 6-12 months, with MRI in the large multicentre setting of the Alzheimer's Disease Neuroimaging Initiative (ADNI); (ii) to determine the extent to which the polymorphism of the apolipoprotein E (ApoE) gene modulates hippocampal change; and (iii) to determine if rates of hippocampal loss correlate with cerebrospinal fluid (CSF) biomarkers of Alzheimer's disease, such as the beta-amyloid (Abeta(1-42)) and tau proteins (tau). The MRI multicentre study included 112 cognitive normal elderly individuals, 226 mild cognitive impairment and 96 Alzheimer's disease patients who all had at least three successive MRI scans, involving 47 different imaging centres. The mild cognitive impairment and Alzheimer's disease groups showed hippocampal volume loss over 6 months and accelerated loss over 1 year. Moreover, increased rates of hippocampal loss were associated with presence of the ApoE allele epsilon4 gene in Alzheimer's disease and lower CSF Abeta(1-42) in mild cognitive impairment, irrespective of ApoE genotype, whereas relations with tau were only trends. The power to measure hippocampal change was improved by exploiting correlations statistically between successive MRI observations. The demonstration of considerable hippocampal loss in mild cognitive impairment and Alzheimer's disease patients over only 6 months and accelerated loss over 12 months illustrates the power of MRI to track morphological brain changes over time in a large multisite setting. Furthermore, the relations between faster hippocampal loss in the presence of ApoE allele epsilon4 and decreased CSF Abeta(1-42) supports the concept that increased hippocampal loss is an indicator of Alzheimer's disease pathology and a potential marker for the efficacy of therapeutic interventions in Alzheimer's disease.

Direct determination of verapamil in rat plasma by coupled column microbore-HPLC method

This report describes an automated coupled column microbore-high-performance liquid chromatography (HPLC) with fluorescence detection for direct determination of verapamil in small volume of rat plasma. We used HPLC system consisting of three columns such as precolumn, intermediate and analytical column and six-port switching valve and injected small volume of rat plasma to the system without sample preparation. An aliquot of sample was directly injected into Capcell Pak MF Ph precolumn for clean-up and enrichment, 35 mm Capcell Pak C18, intermediate column for concentration of compounds and 250 mm Capcell Pak C18 analytical column for separation of compounds and two mobile phases are used as mobile phase A (50mM ammonium phosphate, pH 4.5) and B (50mM ammonium phosphate:acetonitrile=70:30 v/v). Analysis of verapamil and internal standard, propranolol was performed with direct injection of 10 microl of rat plasma to the system and were eluted at 22 and 12 min, respectively, at a mobile phase flow rate of 0.5 (mobile phase A) and 0.15 ml/min (mobile phase B). The peaks of verapamil and internal standard were good shapes and well separated from any interfering endogenous peaks during a total run time of 25 min. The calibration curve for verapamil showed good linearity (r(2)=0.9997) over the concentration range of 0.01-2.50 microg/ml. The mean RSD (%) values of intra-day (n=5) and inter-day (n=5) variability of verapamil ranged from 1.96 to 9.06 and 0.62 to 3.08%, respectively. The LOD and LOQ were 0.01 and 0.025 microg/ml, respectively, for verapamil using 10 microl of rat plasma. An automated coupled column microbore-HPLC method was successfully applied to a pharmacokinetic study after intravenous injection of 3mg/kg of verapamil to the normal and dimethylnitrosamine (DMN)-induced hepatofibrotic rats.

New dosing regimens for amifostine: a pilot study to compare the relative bioavailability of oral and subcutaneous administration with intravenous infusion

A phase I clinical trial was conducted to assess thefeasibility of a more convenient and safe dosing regime for the cytoprotective drug amifostine. Two alternative routes of administration, oral and subcutaneous (s.q.), each with a dose of 500 mg, were compared to a 7.5-minute intravenous (i.v.) infusion, with a dose of 200 mg/m2, in normal, healthy volunteers (N = 12). Bioavailability of amifostine (parent drug) and its pharmacologically active metabolite, WR-1065, was evaluated by comparing the area under the concentration-time curve (AUC) derived from HPLC analysis of amifostine and both protein-free and protein-bound WR-1065 in all three routes of administration. Results showed that SQ (but not oral) administration of amifostine could provide a more effective dosing regimen, in terms of both a reasonable AUC for the bound form of WR-1065 and decreased toxicity, compared to i.v. delivery. These data suggest that the protein-bound form of WR-1065 plays an important role in contributing to the bioavailability of this clinically useful cytoprotective drug.

cag+ Helicobacter pylori induce transactivation of the epidermal growth factor receptor in AGS gastric epithelial cells

The gastric pathogen Helicobacter pylori is known to activate epithelial cell signaling pathways that regulate numerous inflammatory response genes. The aim of this study was to elucidate the pathway leading to extracellular signal-regulated kinase (ERK) 1/2 phosphorylation in H. pylori-infected AGS gastric epithelial cells. We find that H. pylori, via activation of the epidermal growth factor (EGF) receptor activates the small GTP-binding protein Ras, which in turn, mediates ERK1/2 phosphorylation. cag+ strains of H. pylori are able to induce greater EGF receptor activation than cag- strains, and studies with isogenic mutants indicate that an intact type IV bacterial secretion system is required for this effect. Blockade of EGF receptor activation using tyrphostin AG1478 prevents H. pylori-mediated Ras activation, inhibits ERK1/2 phosphorylation, and substantially decreases interleukin-8 gene expression and protein production. Investigations into the mechanism of EGF receptor activation, using heparin, a metalloproteinase inhibitor and neutralizing antibodies reveal that H. pylori transactivates the EGF receptor via activation of the endogenous ligand heparin-binding EGF-like growth factor. Transactivation of gastric epithelial cell EGF receptors may be instrumental in regulating both proliferative and inflammatory responses induced by cag+ H. pylori infection.

The alpha 6 beta 4 integrin and epithelial cell migration

Although the involvement of alpha 6 beta 4, an integrin laminin receptor, in hemidesmosome organization has dominated the study of this integrin, recent studies are revealing novel functions for alpha 6 beta 4 in the migration of epithelial and carcinoma cells. The engagement of laminin by alpha 6 beta 4 can stabilize actin-rich protrusions and mediate traction forces necessary for cell movement. This integrin also has a significant impact on signaling molecules that stimulate migration and invasion, especially PI3-K and Rho GTPases. Activation of PI3-K by alpha 6 beta 4 enhances the formation of actin protrusions, and it may stimulate the function of other integrins, such as alpha 3 beta 1, that are also important for epithelial migration. Signaling through alpha 6 beta 4 may not always depend on the adhesive functions of this integrin, a possibility that has profound implications for migration and invasion because it implies that the ability of alpha 6 beta 4 to stimulate these processes is not limited to specific matrix environments.

Factors associated with changes in serum total cholesterol levels over 7 years in middle-aged New Zealand men and women: a prospective study

BACKGROUND AND AIM

The aim of this study was to determine the factors associated with changes in serum total cholesterol levels over a period of seven years.

METHODS AND RESULTS

The baseline Workforce Diabetes Survey was carried out between 1988 and 1990 and involved workers predominantly aged > or = 40 years; a follow-up survey of 4,053 participants was carried out between 1995 and 1997. Both surveys measured serum lipid levels by means of enzymatic methods. The overall age- and gender-adjusted mean serum cholesterol levels decreased by 4.6% between the two surveys. The two-thirds of participants who experienced a decrease in total serum cholesterol formed a higher risk group at baseline insofar as they were older, more inactive and more likely to be male, and had higher blood pressure (BP), higher serum cholesterol and triglyceride levels, and a higher body mass index (BMI) and waist/hip ratio than the one-third whose serum cholesterol levels increased (all p < 0.05). The decrease in serum cholesterol was associated with improvements or less deterioration in risk factors (fasting glucose, BP, BMI and the waist/hip ratio, the low-density/high-density lipoprotein (LDL/HDL) ratio, triglyceride concentrations and level of physical activity) and an increase in the use of lipid lowering drugs.

CONCLUSION

Serum cholesterol levels decreased over the seven years between the surveys, principally among the individuals at highest risk. The use of lipid lowering drugs contributed to this decline but lifestyle factors, such as increased exercise levels, may also have played a role because other risk factors also improved.

Vascular endothelial growth factor is an autocrine survival factor for neuropilin-expressing breast carcinoma cells

We identify a novel function for the vascular endothelial growth factor (VEGF) in its ability to stimulate an autocrine signaling pathway in metastatic breast carcinoma cells that is essential for their survival. Suppression of VEGF expression in metastatic cells in vitro induced their apoptosis, in addition to inhibiting the constitutively elevated phosphatidylinositol 3'-kinase activity that is characteristic of these cells and important for their survival. Hypoxia enhanced the survival of metastatic cells by increasing VEGF expression. The importance of the VEGF receptor neuropilin was indicated by the ability of a neuropilin-binding VEGF isoform to enhance breast carcinoma survival. Moreover, the expression of neuropilin in neuropilin-deficient breast carcinoma cells protected them from apoptosis. The identification of this VEGF autocrine signaling pathway has important implications for tumor metastasis and therapeutic intervention.

Identification of insulin receptor substrate 1 (IRS-1) and IRS-2 as signaling intermediates in the alpha6beta4 integrin-dependent activation of phosphoinositide 3-OH kinase and promotion of invasion

Expression of the alpha6beta4 integrin increases the invasive potential of carcinoma cells by a mechanism that involves activation of phosphoinositide 3-OH kinase (PI3K). In the present study, we investigated the signaling pathway by which the alpha6beta4 integrin activates PI3K. Neither the alpha6 nor the beta4 cytoplasmic domain contains the consensus binding motif for PI3K, pYMXM, indicating that additional proteins are likely to be involved in the activation of this lipid kinase by the alpha6beta4 integrin. We identified insulin receptor substrate 1 (IRS-1) and IRS-2 as signaling intermediates in the activation of PI3K by the alpha6beta4 integrin. IRS-1 and IRS-2 are cytoplasmic adapter proteins that do not contain intrinsic kinase activity but rather function by recruiting proteins to surface receptors, where they organize signaling complexes. Ligation of the alpha6beta4 receptor promotes tyrosine phosphorylation of IRS-1 and IRS-2 and increases their association with PI3K, as determined by coimmunoprecipitation. Moreover, we identified a tyrosine residue in the cytoplasmic domain of the beta4 subunit, Y1494, that is required for alpha6beta4-dependent phosphorylation of IRS-2 and activation of PI3K in response to receptor ligation. Most importantly, Y1494 is essential for the ability of the alpha6beta4 integrin to promote carcinoma invasion. Taken together, these results imply a key role for the IRS proteins in the alpha6beta4-dependent promotion of carcinoma invasion.

Integrin laminin receptors and breast carcinoma progression

This review explores the mechanistic basis of breast carcinoma progression by focusing on the contribution of integrins. Integrins are essential for progression not only for their ability to mediate physical interactions with extracellular matrices but also for their ability to regulate signaling pathways that control actin dynamics and cell movement, as well as for growth and survival. Our comments center on the alpha6 integrins (alpha6beta1 and alpha6beta4), which are receptors for the laminin family of basement membrane components. Numerous studies have implicated these integrins in breast cancer progression and have provided a rationale for studying the mechanistic basis of their contribution to aggressive disease. Recent work by our group and others on mechanisms of breast carcinoma invasion and survival that are influenced by the alpha6 integrins are discussed.

Clinical utility of monitoring tacrolimus blood concentrations in liver transplant patients

The relationship between the dose of tacrolimus, trough tacrolimus blood concentration, and selected clinical endpoints (acute rejection, nephrotoxicity, and other toxicities) were examined in a prospective, multicenter clinical trial to validate the use of an enzyme-linked immunosorbent assay (ELISA) for monitoring whole-blood concentrations of tacrolimus in liver transplant patients. A total of 111 subjects from six transplant centers were evaluated over 12 weeks posttransplantation. In addition to trough tacrolimus blood concentrations, hematocrit, ALT, AST, GGTP, alkaline phosphatase, total bilirubin, serum creatinine, BUN, serum potassium, serum magnesium, blood glucose, and serum albumin were also measured. The relationship between trough tacrolimus blood concentrations and clinical endpoints was analyzed using both a logistic regression model and a Cox proportional hazard model. By logistic regression analysis, a statistically significant (p = 0.0465) relationship between increasing trough tacrolimus blood concentrations and decreasing risk of acute rejection was demonstrated over a 7-day time window. Nephrotoxicity and other toxicities also demonstrated statistically significant relationships with trough tacrolimus blood concentrations. The results of the Cox analysis were consistent with the logistic regression analysis. Using receiver operator characteristic curves, trough tacrolimus concentrations as measured by the ELISA method were able to differentiate the occurrence of nephrotoxicity and toxicity from nonevents. To minimize nephrotoxicity of tacrolimus, it is necessary to maintain trough blood concentrations below 15 ng/ml. This study demonstrates that the ELISA method used to measure tacrolimus blood concentrations in this study provides information of predictive value for managing the risk of nephrotoxicity, other toxicity, and rejection in liver transplant patients.

The metastatic odyssey: the integrin connection

This article explores the mechanistic basis of carcinoma progression by focusing on the contribution of integrins. Integrins are essential for progression because of their ability to mediate physical interactions with extracellular matrices and their ability to regulate signaling pathways that control actin dynamics and cell movement, and for growth and survival. This article centers on a6 integrins (a6B1 and a6B4), which are receptors for the laminin family of basement membrane components. Numerous studies have implicated these integrins in cancer progression and have provided a rationale for studying the mechanistic basis of their contribution to aggressive disease.

Pharmacokinetic, pharmacodynamic, and outcome investigations as the basis for mycophenolic acid therapeutic drug monitoring in renal and heart transplant patients

Mycophenolate mofetil is widely used in combination with either cyclosporine or tacrolimus for rejection prophylaxis in renal and heart transplant patients. Although not monitored routinely nearly to the degree that other agents such as cyclosporine or tacrolimus, there is an expanding body of experimental evidence for the utility of monitoring mycophenolic acid, the primary active metabolite of mycophenolate mofetil, plasma concentration as an index of risk for the development of acute rejection. The following are important experimentally-based reasons for recommending the incorporation of target therapeutic concentration monitoring of mycophenolic acid: (1) the MPA dose-interval area-under-the-concentration-time curve, and less precisely, MPA predose concentrations predict the risk for development of acute rejection; (2) the strong correlation between mycophenolic acid plasma concentrations and expression of important cell surface activation antigens, whole blood pharmacodynamic assays of lymphocyte proliferation and median graft rejection scores in a heart transplant animal model; (3) the greater than 10-fold interindividual variation of MPA area under the concentration time curve values in heart and renal transplant patients receiving a fixed dose of the parent drug; (4) drug-drug interactions involving other immunosuppressives are such that when switching from one to another (eg, from cyclosporine to tacrolimus or vice-versa) substantial changes in MPA concentrations can occur in patients receiving a fixed dose of the parent drug; (5) significant effects of liver and kidney diseases on the steady-state total and free mycophenolic acid area under the concentration time curve values; (6) the need to closely monitor mycophenolic acid when a major change in immunosuppression is planned such as steroid withdrawal. Current investigations are focused on determination of the most optimal sampling time and for mycophenolic acid target therapeutic concentration monitoring. Further investigations are needed to evaluate the pharmacologic activity of the newly described acyl glucuronide metabolite of mycophenolic acid which has been shown to inhibit, in vitro, inosine monophosphate dehydrogenase.

Mycophenolic acid concentrations are associated with cardiac allograft rejection

BACKGROUND

Mycophenolate mofetil (MMF) therapy decreases the incidence of allograft rejection following solid-organ transplantation. Current dosing strategies of MMF are not routinely adjusted based on mycophenolic acid (MPA) area under the concentration-time curve (AUC), MPA trough, or free MPA (fMPA) AUC values.

METHODS

To determine the clinical significance of MPA concentrations following orthotopic heart transplantation (OHT), we measured pre-dose MPA trough, MPA free fraction, an estimated MPA AUC using an abbreviated sampling schedule, and fMPA AUC in 38 consecutive patients. We measured MPA concentrations using a validated high-performance liquid chromatography method and graded endomyocardial biopsies based on the International Society for Heart and Lung Transplantation (ISHLT) grading system.

RESULTS

The MPA values for the study group were as follows: MPA trough of 1.2 +/- 0.6 microg/ml; MPA free fraction of 1.9 +/- 0.4%; MPA AUC of 44.5 +/- 16. 1 microg/hour/ml; and fMPA AUC of 0.83 +/- 0.30 microg/hour/ml. We compared patients with Grade 0 (n = 22), Grade 1 (n = 13), or Grade 2/3 (n = 3). The MPA AUC values were lower in patients with Grade 2/3 than in patients with Grade 0 (26.1 +/- 6.6 vs 42.8 +/- 14.0 microg/hour/ml, p < 0.08) or Grade 1 rejection (26.1 +/- 6.6 vs 51.7 +/- 17.5 microg/hour/ml, p < 0.05). The fMPA AUC values were lower in patients with Grade 2/3 than with patients with Grade 0 (0.49 +/- 0.11 vs 0.81 +/- 0.25 microg/hour/ml, p < 0.05) or Grade 1 (0.49 +/- 0.25 vs 0.95 +/- 0.34 microg/hour/ml, p < 0.05) rejection. We noted a trend in MPA trough concentrations between patients with Grade 2/3 vs 0 (0.65 +/- 0.15 vs 1.20 +/- 0.58 microg/ml, p = 0.15) and Grade 1 (0.65 +/- 0.15 vs 1.24 +/- 0.72 microg/ml, p = 0.14) rejection.

CONCLUSION

These preliminary results suggest that lower MPA AUC and fMPA AUC values are associated with cardiac allograft rejection in heart transplant recipients. Individualizing MMF dosing based on MPA determinations may minimize the risk of rejection following OHT.

Mycophenolic acid area under the curve values in African American and Caucasian renal transplant patients are comparable

The possibility of an effect of ethnicity on the pharmacokinetics of mycophenolic acid, the immunosuppressive metabolite of the prodrug mycophenolate mofetil, was studied over 90 days following renal transplantation in African American (n = 13) and Caucasian patients (n = 20). Since renal dysfunction and time after transplant surgery are two factors known to alter mycophenolic acid pharmacokinetics, two-way analysis of variance of the data at each time point with ethnicity and renal function status as covariates was used to evaluate the possibility of an ethnicity effect on the pharmacokinetic parameters. No statistically significant difference based on ethnicity was detected for the primary pharmacokinetic parameters, abbreviated mycophenolic acid area under the concentration-time curve (MPA AUC), or the predose trough concentration on study days 4, 7, 14, 28, or 90. A statistically significant decrease in MPA AUC and increase in oral apparent clearance were observed in renally impaired patients regardless of ethnicity on days 4, and 4 and 7, respectively. The suggested mechanism for these differences is uremia-induced increased MPA free fraction, leading to a temporary increased clearance for this restrictively cleared drug.

Substance use measures among women in early pregnancy

OBJECTIVE

Our purpose was to compare self-reported and biochemical measures for tobacco, marijuana, and cocaine exposures among women early in pregnancy.

STUDY DESIGN

Women who were in the early stages of pregnancy and were examined in an inner-city emergency department were enrolled. Tobacco, marijuana, and cocaine use was measured by self-report and urinalysis. Cocaine use was also assessed by hair analysis.

RESULTS

Data were available for 789 women. Among those reporting past use of tobacco, marijuana, and cocaine, 25.2%, 23.9%, and 22.7%, respectively, had positive results of urinary assays; among those reporting current use, 77.2%, 86.6%, and 75.9% had positive findings, whereas among those reporting never use 5.6%, 5. 7%, and 3.6% of results were positive. Hair analysis, in comparison with urine testing, for cocaine identified 4 times as many exposures among women who reported never using cocaine.

CONCLUSIONS

Urinary assays were equally likely to be positive among women reporting never use and those reporting past use of tobacco, marijuana, or cocaine. Thus women with a positive biologic assay result were as likely to deny use of tobacco as they were to deny marijuana, or cocaine.

Mycophenolic acid area under the curve values in African American and Caucasian renal transplant patients are comparable

The possibility of an effect of ethnicity on the pharmacokinetics of mycophenolic acid, the immunosuppressive metabolite of the prodrug mycophenolate mofetil, was studied over 90 days following renal transplantation in African American (n = 13) and Caucasian patients (n = 20). Since renal dysfunction and time after transplant surgery are two factors known to alter mycophenolic acid pharmacokinetics, two-way analysis of variance of the data at each time point with ethnicity and renal function status as covariates was used to evaluate the possibility of an ethnicity effect on the pharmacokinetic parameters. No statistically significant difference based on ethnicity was detected for the primary pharmacokinetic parameters, abbreviated mycophenolic acid area under the concentration-time curve (MPA AUC), or the predose trough concentration on study days 4, 7, 14, 28, or 90. A statistically significant decrease in MPA AUC and increase in oral apparent clearance were observed in renally impaired patients regardless of ethnicity on days 4, and 4 and 7, respectively. The suggested mechanism for these differences is uremia-induced increased MPA free fraction, leading to a temporary increased clearance for this restrictively cleared drug.

The immunosuppressive macrolide RAD inhibits growth of human Epstein-Barr virus-transformed B lymphocytes in vitro and in vivo: A potential approach to prevention and treatment of posttransplant lymphoproliferative disorders

Whereas the standard immunosuppressive agents foster development of posttransplant lymphoproliferative disorders (PTLDs), the impact of RAD, a macrolide with potent immunosuppressive properties, and other immunosuppressive macrolides on these disorders remains undetermined. We found that RAD had a profound inhibitory effect on in vitro growth of six different PTLD-like Epstein-Barr virus+ lymphoblastoid B cell lines. Similar to normal T cells, RAD blocked cell-cycle progression in PTLD-like B cells in the early (G(0)/G(1)) phase. Furthermore, RAD increased the apoptotic rate in such cells. The drug also had a profound inhibitory effect on the growth of PTLD-like Epstein-Barr virus+ B cells xenotransplanted s.c. into SCID mice. The degree of the RAD effect varied among the three B cell lines tested and was proportional to its effects on the cell lines in vitro. In this in vivo xenotransplant model, RAD markedly delayed growth or induced regression of the established tumors. In one line, it was able to eradicate the tumor in four of eight mice. When RAD treatment was initiated before tumor cell injection, a marked inhibition of tumor growth was seen in all three lines. In two of them, the drug prevented tumor establishment in approximately 50% of mice (5/11 and 5/8). In summary, RAD is a potent inhibitor of PTLD-like cells in vitro and in vivo. These findings indicate that, in contrast to the standard immunosuppressive agents, macrolides such as RAD may be effective in prevention and treatment of PTLDs.

Measurement of both protein-bound and total S-2-(3-aminopropylamino)ethanethiol (WR-1065) in blood by high-performance liquid chromatography

A high-performance liquid chromatographic method for automated analysis of both protein-bound and total S-2-(3-aminopropylamino)ethanethiol (WR-1065) in blood has been developed in our laboratory. WR-1065 is the active thiol metabolite of the radio- and chemo-protector drug amifostine (WR-2721). Using WR-1065 quality control levels over the experimental range: 7.0, 45.0 and 85.0 micromol/l spiked into plasma, method validation for total WR-1065 included between-run assessment of imprecision (SD/C.V.%: 1.11/16.7%, 6.58/15.5% and 9.24/11.3%, respectively) and % accuracy (94.7, 106.0 and 97.2%).

Drg-1 as a differentiation-related, putative metastatic suppressor gene in human colon cancer

A gene related to cell differentiation was identified by differential display as a candidate suppressor of metastases in colon cancer. This gene, with a full-length cDNA of 3 kb, is expressed in normal colon and primary colon cancer tissues and cell lines but not in their metastatic counterparts. A GenBank search found that it is identical to a recently cloned gene, differentiation-related gene-1 (Drg-1), isolated from differentiated HT-29 colon cancer cells. Stable transfection of the SW620 metastatic colon cancer cell line with Drg-1 cDNA induced morphological changes consistent with differentiation and up-regulated the expression of several colonic epithelial cell differentiation markers (alkaline phosphatase, carcinoembryonic antigen, and E-cadherin). Moreover, the expression of Drg-1 is controlled by several known cell differentiation reagents, such as ligands of peroxisome proliferator-activated receptor gamma (troglitazone and BRL46593) and of retinoid X receptor (LG268), and histone deacetylase inhibitors (trichostatin A, suberoylanilide hydroxamic acid, and tributyrin). A synergistic induction of Drg-1 expression was seen with the combination of tributyrin and a low dose of 5'-aza-2'-dexoycytidine (100 nM), an inhibitor of DNA methylation. Functional studies revealed that overexpression of Drg-1 in metastatic colon cancer cells reduced in vitro invasion through Matrigel and suppressed in vivo liver metastases in nude mice. We propose that Drg-1 suppresses colon cancer metastasis by inducing colon cancer cell differentiation and partially reversing the metastatic phenotype.

Pharmacokinetics and concentration-control investigations of mycophenolic acid in adults after transplantation

Data have emerged that provide the scientific basis for therapeutic drug monitoring of mycophenolic acid (MPA) in transplant patients receiving mycophenolate mofetil (MMF), the parent drug, in combination with other immunosuppressive agents. There is a significant relationship between the dose-interval MPA AUC and risk for acute rejection based on retrospective investigations in renal and heart transplant patients and on prospective investigations in renal transplant patients. The MPA dose-interval AUC varies naturally by more than 10-fold in renal and heart transplant patients. Other significant sources of pharmacokinetic variability for MPA include the effects of concomitant medications, and the effects of disease states such as renal dysfunction and liver disease on the steady state MPA AUC. Individualized MMF dose evaluation, guided by MPA plasma concentrations, is becoming the standard of practice at a growing number of transplant centers worldwide because of these factors and because of the need to closely evaluate the immunosuppression afforded by MPA when a change in the immunosuppression regimen in stable transplant patients is planned. Investigations of therapeutic drug monitoring strategies with an emphasis on identifying an optimal abbreviated sampling strategy for MPA AUC estimation are ongoing. Based on the concentration-outcome studies and experience at the authors' institutions and other centers, the authors propose a set of therapeutic drug monitoring guidelines for MPA in stable renal and heart transplant patients for the immediate (first 3 months posttransplant) and maintenance (>3 months) periods. When MPA binding to human serum albumin is altered, as occurs in patients with significant renal dysfunction, liver disease, or a substantial reduction in human serum albumin concentration, the possibility of increased MPA free fraction and free concentration will need to be taken into account in the interpretation of MPA total concentrations.

Pharmacokinetics of mycophenolic acid in renal insufficiency

Mycophenolate mofetil (MMF) is now widely used in solid organ transplantation. MMF is rapidly converted to its active form, mycophenolic acid (MPA), upon reaching the systemic circulation. MPA is metabolized to its glucuronide metabolite, mycophenolic acid glucuronide (MPAG), by glucoronyl transferases in the liver and possibly elsewhere. MPAG is then excreted by the kidney. MPA is extensively and avidly bound to serum albumin. Previous studies have demonstrated that it is only the free (non-protein-bound) fraction of MPA that is available to exert its action. In vivo and in vitro studies demonstrate that renal insufficiency decreases the protein binding of MPA and increases free MPA concentrations. This decrease in protein binding seems to be caused both by the uremic state itself and by competition with the retained metabolite MPAG. The disposition of MPA in patients with severe renal impairment may be significantly affected by this change in protein binding.

Violent injuries among women in an urban area

The national statistics are familiar by now: each year, more than 2 million women are raped and/or physically assaulted; more than one-third of them are injured during their most recent assault. Annually, more than 500,000 women seek medical services as a result of violence-related injuries, often from hospital emergency departments. But national statistics cannot fully capture the extent of violence experienced by women in inner-city areas, nor do they point to modifiable risk factors at a community level. This Issue Brief highlights a new study that investigates the circumstances and correlates of violent injuries among women in one urban, low-income community.

Violent injuries among women in an urban area

BACKGROUND

Although the rate of death from injuries due to violent acts is much higher among black women than among white women in the United States, little is known about the nature and correlates of violent injuries among black women living in urban areas.

METHODS

In this case-control study conducted at three emergency departments in one inner-city community (in west Philadelphia), we studied 405 adolescent girls and women who had been intentionally injured and 520 adolescent girls and women (control subjects) who had health problems not related to violent injury. Data were collected by conducting standardized interviews with use of questionnaires and by screening urine for illicit drugs. Individual logistic-regression models were constructed to identify factors associated with violent injuries inflicted by partners and those inflicted by persons other than the partners of the victims.

RESULTS

The male partners of the injured women were much more likely than the male partners of control subjects to use cocaine (odds ratio, 4.4; 95 percent confidence interval, 2.3 to 8.4) and to have been arrested in the past (odds ratio, 3.1; 95 percent confidence interval, 1.8 to 5.2). Fifty-three percent of violent injuries to the women had been perpetrated by persons other than their partners. Women's use of illicit drugs and alcohol abuse were factors associated with both violence on the part of partners and violence on the part of other persons. Neighborhood characteristics, including low median income, a high rate of change of residence, and poor education, were independently associated with the risk of violent injuries among women.

CONCLUSIONS

Women in this urban, low-income community face violence from both partners and other persons. Substance abuse, particularly cocaine use, is a significant correlate of violent injuries. Standard Census data may help identify neighborhoods where women are at high risk for such violence and that would benefit from community-level interventions.

Analysis of whole blood tacrolimus concentrations in liver transplant patients exhibiting impaired liver function

In transplant patients with impaired liver function, HPLC methodologies have been suggested for monitoring whole blood tacrolimus concentrations because of the reported inaccuracy of immunoassay for whole blood tacrolimus concentrations. One hundred fifty whole blood samples from 50 subjects enrolled in a multicenter liver transplant trial were chosen for HPLC/MS/MS analysis without consideration of the clinical status of the patient at the time of sampling. These samples were chosen to represent the sampling intervals during the 12-week posttransplantation period. Retrospectively, the authors identified a subset of 39 samples from 27 subjects exhibiting impaired liver function as demonstrated by bilirubin concentrations > 3.0 mg/dL (mean +/-SD = 7.5 +/- 5.6 mg/dL). The authors compared the agreement of concentrations obtained from the PRO-Trac II ELISA and HPLC/MS/MS by least squares linear regression analysis and Bland/Altman analysis, in this subset against the agreement of concentrations for 76 samples with normal bilirubin. In the samples obtained from patients with impaired liver function the resulting regression equation was: ELISA = 1.19(HPLC) + 0.7; r = 0.9. The mean difference (HPLC/MS/MS - ELISA) was -2.5 ng/mL +/- 2.9 ng/mL (mean +/- SD). While 71% of samples agreed within 3 ng/mL, 3% (n = 1) exhibited a difference >10 ng/ml. The corresponding evaluation of the samples with normal bilirubin concentrations resulted in the regression equation ELISA = 0.96(HPLC) + 0.9; r = 0.9, and a mean difference of -0.6 ng/mL +/- 2.3 ng/mL. The authors conclude that while a small subset of patients with cholestasis may require closer evaluation with a more specific methodology, the majority of the patients may be satisfactorily monitored with the PRO-Trac II ELISA.

Current opinions on therapeutic drug monitoring of immunosuppressive drugs

The pharmacokinetics of the immunosuppressive drugs cyclosporine, tacrolimus, mycophenolate mofetil (MMF), and sirolimus are complex and unpredictable. A narrow therapeutic index unique to each patient, as well as variable absorption, distribution, and elimination, are characteristics of these drugs. Therapeutic drug monitoring plays a key role in helping clinicians maintain blood and plasma levels of immunosuppressive drugs within their respective therapeutic ranges. Variation in concentrations outside the narrow therapeutic ranges can result in adverse clinical outcomes. Therapeutic drug monitoring ensures that concentrations are not too high or too low, thereby reducing the risks of toxicity or rejection, respectively. Therapeutic monitoring of immunosuppressive drugs has been based on several choices of assay and biologic fluid (i.e., whole blood, plasma) appropriate for a particular drug. High-performance liquid chromatography (HPLC) remains the gold standard among assay methods used to monitor immunosuppressive drugs. Although HPLC is the assay of choice for cyclosporine, newer monoclonal assays are suitable as well for routine monitoring. HPLC is also widely used for therapeutic drug monitoring of mycophenolic acid, the active metabolite of MMF, and an immunoassay (used in European centers) has been developed. Therapeutic drug monitoring of tacrolimus has been improved with the recent development of assays with greater sensitivity and specificity for tacrolimus than those previously available. No commercial assays are currently available for the therapeutic monitoring of sirolimus. It is also important to identify a specific pharmacokinetic parameter for each individual drug, whether it is trough or area under the concentration-time curve, that may be most useful as a tool for optimal therapeutic drug monitoring in clinical practice. With an increased understanding of the pharmacokinetics of immunosuppressive drugs, therapeutic drug monitoring guidelines will be more clearly defined to ensure the safe and effective management of transplant recipients.

Integrin function in breast carcinoma progression

The differentiation and function of mammary epithelial cells is dependent upon the combined action of growth factor/hormone receptors and integrin receptors, which act in concert to control the signals required for normal cell function. It is now becoming clear that integrin receptors also contribute to carcinoma cell behavior and that alterations in expression and function during transformation have a large impact on breast carcinoma progression. The focus of this review is to discuss integrin-dependent functions that can be manipulated as targets for the therapeutic intervention of breast cancer. A combination of correlative and mechanistic studies have contributed to the identification of specific integrin receptors, namely alpha2beta1, alpha6beta1, and alpha6beta4, implicated in breast carcinoma progression. Although this field is still emerging and much remains to be learned, potential integrin-dependent signaling targets have been identified.