Comparing the Standard and Electronic Versions of the Alzheimer's Disease Assessment Scale - Cognitive Subscale: A Validation Study.

The Alzheimer's Disease Assessment Scale (ADAS-Cog) has become the de facto gold-standard for assessing the efficacy of putative anti-dementia treatments. There has been an increasing interest in providing greater standardization, automation, and administration consistency to the scale. Recently, electronic versions of the ADAS-Cog (eADAS-Cog) have been utilized in clinical trials and demonstrated significant reductions in frequency of rater error as compared to paper. In order to establish validity of the electronic version (eADAS-Cog), 20 subjects who had received a diagnosis of probable Alzheimer's disease (AD) at a private US Memory Clinic completed a single-center, randomized, counterbalanced, prospective trial comparing a version of the eADAS-Cog to the standard paper scale. Interclass Correlation Coefficient on total scores and Kappa analysis on domain scores yielded high agreement (0.88 - 0.99). Effects of order and mode of administration on ADAS-Cog total scores did not demonstrate a significant main effect. Overall, this study establishes adequate concurrent validity between the ADAS-Cog and eADAS-Cog among an adult population with diagnosed AD.

Endometrial carcinoma recurrence according to race and ethnicity: An NRG Oncology/Gynecologic Oncology Group 210 Study.

Non-Hispanic black (NHB) women are more likely to experience an endometrial carcinoma (EC) recurrence compared to non-Hispanic white (NHW) women. The extent to which tumor characteristics, socioeconomic status (SES) and treatment contribute to this observation is not well defined. In the NRG Oncology/Gynecology Oncology Group (GOG) 210 Study we evaluated associations between race/ethnicity and EC recurrence according to tumor characteristics with adjustment for potential confounders. Our analysis included 3,199 NHW, 532 NHB and 232 Hispanic women with EC. Recurrence was documented during follow-up. We used Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between race/ethnicity and EC recurrence in models stratified by histologic subtype (low-grade endometrioid, high-grade endometrioid, serous, mixed cell, carcinosarcoma, clear cell) or stage (I, II, III) and adjusted for age, SES, body mass index, smoking status and treatment. In histologic subtype-stratified models, higher EC recurrence was noted in NHB women with low-grade endometrioid (HR = 1.94, 95% CI = 1.21-3.10) or carcinosarcomas (HR = 1.66, 95% CI = 0.99-2.79) compared to NHWs. In stage-stratified models, higher EC recurrence was noted among NHB women with stage I (HR = 1.48, 95% CI = 1.06-2.05) and Hispanic women with stage III disease (HR = 1.81, 95% CI = 1.11-2.95). Our observations of higher EC recurrence risk among NHB and Hispanic women, as compared to NHW women, were not explained by tumor characteristics, SES, treatment or other confounders. Other factors, such as racial differences in tumor biology or other patient factors, should be explored as contributors to racial disparities in EC recurrence.

Behavioral deficits induced by third-trimester equivalent alcohol exposure in male C57BL/6J mice are not associated with reduced adult hippocampal neurogenesis but are still rescued with voluntary exercise.

Prenatal alcohol exposure can produce permanent alterations in brain structure and profound behavioral deficits. Mouse models can help discover mechanisms and identify potentially useful interventions. This study examined long-term influences of either a single or repeated alcohol exposure during the third-trimester equivalent on survival of new neurons in the hippocampus, behavioral performance on the Passive avoidance and Rotarod tasks, and the potential role of exercise as a therapeutic intervention. C57BL/6J male mice received either saline or 5g/kg ethanol split into two s.c. injections, two hours apart, on postnatal day (PD)7 (Experiment 1) or on PD5, 7 and 9 (Experiment 2). All mice were weaned on PD21 and received either a running wheel or remained sedentary from PD35-PD80/81. From PD36-45, mice received i.p. injections of 50mg/kg bromodeoxyuridine (BrdU) to label dividing cells. Behavioral testing occurred between PD72-79. Number of surviving BrdU+ cells and immature neurons (doublecortin; DCX+) was measured at PD80-81. Alcohol did not affect number of BrdU+ or DCX+ cells in either experiment. Running significantly increased number of BrdU+ and DCX+ cells in both treatment groups. Alcohol-induced deficits on Rotarod performance and acquisition of the Passive avoidance task (Day 1) were evident only in Experiment 2 and running rescued these deficits. These data suggest neonatal alcohol exposure does not result in long-term impairments in adult hippocampal neurogenesis in the mouse model. Three doses of ethanol were necessary to induce behavioral deficits. Finally, the mechanisms by which exercise ameliorated the neonatal alcohol induced behavioral deficits remain unknown.

Regulation of ABC transporters at the blood-brain barrier.

ATP binding cassette (ABC) transporters at the blood-brain barrier function as ATP-driven xenobiotic efflux pumps and limit delivery of small molecule drugs to the brain. Here I review recent progress in understanding the regulation of the expression and transport activity of these transporters and comment on how this new information might aid in improving drug delivery to the brain.

Evaluation of a C57BL/6J × 129S1/SvImJ Hybrid Nestin-Thymidine Kinase Transgenic Mouse Model for Studying the Functional Significance of Exercise-Induced Adult Hippocampal Neurogenesis.

New neurons are continuously generated in the adult hippocampus but their function remains a mystery. The nestin thymidine kinase (nestin-TK) transgenic method has been used for selective and conditional reduction of neurogenesis for the purpose of testing the functional significance of new neurons in learning, memory and motor performance. Here we explored the nestin-TK model on a hybrid genetic background (to increase heterozygosity, and "hybrid vigor"). Transgenic C57BL/6J (B6) were crossed with 129S1/SvImJ (129) producing hybrid offspring (F1) with the B6 half of the genome carrying a herpes simplex virus thymidine kinase (TK) transgene regulated by a modified nestin promoter. In the presence of exogenously administered valganciclovir, new neurons expressing TK undergo apoptosis. Female B6 nestin-TK mice (n = 80) were evaluated for neurogenesis reduction as a positive control. Male and female F1 nestin-TK mice (n = 223) were used to determine the impact of neurogenesis reduction on the Morris water maze (MWM) and rotarod. All mice received BrdU injections to label dividing cells and either valganciclovir or control chow, with or without a running wheel for 30 days. Both the F1 and B6 background displayed approximately 50% reduction in neurogenesis, a difference that did not impair learning and memory on the MWM or rotarod performance. Running enhanced neurogenesis and performance on the rotarod but not MWM suggesting the F1 background may not be suitable for studying pro-cognitive effects of exercise on MWM. Greater reduction of neurogenesis may be required to observe behavioral impacts. Alternatively, new neurons may not play a critical role in learning, or compensatory mechanisms in pre-existing neurons could have masked the deficits. Further work using these and other models for selectively reducing neurogenesis are needed to establish the functional significance of adult hippocampal neurogenesis in behavior.

Increased adult hippocampal neurogenesis is not necessary for wheel running to abolish conditioned place preference for cocaine in mice.

Recent evidence suggests that wheel running can abolish conditioned place preference (CPP) for cocaine in mice. Running significantly increases the number of new neurons in the hippocampus, and new neurons have been hypothesised to enhance plasticity and behavioral flexibility. Therefore, we tested the hypothesis that increased neurogenesis was necessary for exercise to abolish cocaine CPP. Male nestin-thymidine kinase transgenic mice were conditioned with cocaine, and then housed with or without running wheels for 32 days. Half of the mice were fed chow containing valganciclovir to induce apoptosis in newly divided neurons, and the other half were fed standard chow. For the first 10 days, mice received daily injections of bromodeoxyuridine (BrdU) to label dividing cells. On the last 4 days, mice were tested for CPP, and then euthanized for measurement of adult hippocampal neurogenesis by counting the number of BrdU-positive neurons in the dentate gyrus. Levels of running were similar in mice fed valganciclovir-containing chow and normal chow. Valganciclovir significantly reduced the numbers of neurons (BrdU-positive/NeuN-positive) in the dentate gyrus of both sedentary mice and runner mice. Valganciclovir-fed runner mice showed similar levels of neurogenesis as sedentary, normal-fed controls. However, valganciclovir-fed runner mice showed the same abolishment of CPP as runner mice with intact neurogenesis. The results demonstrate that elevated adult hippocampal neurogenesis resulting from running is not necessary for running to abolish cocaine CPP in mice.

Chronic D-amphetamine administered from childhood to adulthood dose-dependently increases the survival of new neurons in the hippocampus of male C57BL/6J mice.

Adderall is widely prescribed for attention deficit hyperactivity disorder (ADHD) though long term neurological effects of the main ingredient d-amphetamine are not well understood. The purpose of this study was to examine effects of clinically prescribed doses of d-amphetamine and one abuse dose administered from childhood to adulthood on adult hippocampal neurogenesis and activation of the granule layer of the dentate gyrus. Beginning in early adolescence (age 28 days) to adulthood (age 71), male C57BL/6J mice were administered twice daily i.p. injections of vehicle, 0.25, 0.5 or 2mg/kg d-amphetamine. Locomotor activity was measured in home cages by video tracking. At age 53-56, mice received bromodeoxyuridine (BrdU) injections to label dividing cells. Immunohistochemical detection of BrdU, neuronal nuclear protein (NeuN), doublecortin (DCX) and Ki67 was used to measure neurogenesis and cell proliferation at age 71. ΔFosB was measured as an indicator of repeated neuronal activation. An additional cohort of mice was treated similarly except euthanized at age 58 to measure activation of granule neurons from d-amphetamine (by detection of c-Fos) and cell proliferation (Ki67) at a time when the fate of BrdU cells would have been determined in the first cohort. d-Amphetamine dose-dependently increased survival and differentiation of BrdU cells into neurons and increased number of DCX cells without affecting the number of Ki67 cells. Low doses of d-amphetamine decreased c-Fos and ΔFosB in the granule layer. Only the high dose induced substantial locomotor stimulation and sensitization. Results suggest both therapeutic and abuse doses of d-amphetamine increase the number of new neurons in the hippocampus when administered from adolescence to adulthood by increasing survival and differentiation of cells into neurons not by increasing progenitor cell proliferation. Mechanisms for amphetamine-induced neurogenesis are unknown but appear activity independent. Results suggest part of the beneficial effects of therapeutic doses of d-amphetamine for ADHD could be via increased hippocampal neurogenesis.

Induction of c-Fos, Zif268, and Arc from acute bouts of voluntary wheel running in new and pre-existing adult mouse hippocampal granule neurons.

The functional significance of newly formed granule neurons in the adult mammalian hippocampus remains a mystery. Recently, it was demonstrated that wheel running increases new neuron survival and c-Fos expression in new and pre-existing granule cells in an activity-dependent manner. It is currently unknown whether other immediate early genes (IEGs) become expressed in granule neurons from running. Further, it is unknown whether locomotor activity in home cages without wheels can influence neurogenesis and IEG expression similar to running. The purpose of this study was three-fold: (1) to determine if Arc and Zif268 expression are also induced from wheel running in both pre-existing and newly formed neurons (2) to determine if neurogenesis and IEG induction is related to horizontal distance traveled in home cages without wheels, and (3) to determine whether IEG induction is related to acute bouts of running or chronic effects. Adult C57BL/6J female mice were placed in cages with or without running wheels for 31 days. The first 10 days, mice received daily injections of 5-Bromo-2'-deoxyuridine (BrdU) to label dividing cells. On day 1, running and non-running animals were euthanized either 2 h after peak activity, or during a period of relative inactivity. Immunohistochemistry was performed on hippocampal sections with antibodies against BrdU, mature neuron marker NeuN, c-Fos, Arc, and Zif268. Results demonstrate that Arc, Zif268, and c-Fos are induced from wheel running but not movement in cages without wheels. All IEGs were expressed in new neurons from running. Further, IEGs were induced acutely by running, as increased expression did not continue into the light cycle, a period of relative inactivity. The results suggest that robust movements, like running, are necessary to stimulate IEG expression and neurogenesis. Moreover, results suggest new neurons from running may be processing information about running behavior itself.

Genetic influences on exercise-induced adult hippocampal neurogenesis across 12 divergent mouse strains.

New neurons are continuously born in the hippocampus of several mammalian species throughout adulthood. Adult neurogenesis represents a natural model for understanding how to grow and incorporate new nerve cells into preexisting circuits in the brain. Finding molecules or biological pathways that increase neurogenesis has broad potential for regenerative medicine. One strategy is to identify mouse strains that display large vs. small increases in neurogenesis in response to wheel running so that the strains can be contrasted to find common genes or biological pathways associated with enhanced neuron formation. Therefore, mice from 12 different isogenic strains were housed with or without running wheels for 43 days to measure the genetic regulation of exercise-induced neurogenesis. During the first 10 days mice received daily injections of 5-bromo-2'-deoxyuridine (BrdU) to label dividing cells. Neurogenesis was measured as the total number of BrdU cells co-expressing NeuN mature neuronal marker in the hippocampal granule cell layer by immunohistochemistry. Exercise increased neurogenesis in all strains, but the magnitude significantly depended on genotype. Strain means for distance run on wheels, but not distance traveled in cages without wheels, were significantly correlated with strain mean level of neurogenesis. Furthermore, certain strains displayed greater neurogenesis than others for a fixed level of running. Strain means for neurogenesis under sedentary conditions were not correlated with neurogenesis under runner conditions suggesting that different genes influence baseline vs. exercise-induced neurogenesis. Genetic contributions to exercise-induced hippocampal neurogenesis suggest that it may be possible to identify genes and pathways associated with enhanced neuroplastic responses to exercise.

Estrogen receptor beta signaling through phosphatase and tensin homolog/phosphoinositide 3-kinase/Akt/glycogen synthase kinase 3 down-regulates blood-brain barrier breast cancer resistance protein.

Breast cancer resistance protein (BCRP) is an ATP-driven efflux pump at the blood-brain barrier that limits central nervous system pharmacotherapy. Our previous studies showed rapid loss of BCRP transport activity in rat brain capillaries exposed to low concentrations of 17-beta-estradiol (E2); this occurred without acute change in BCRP protein expression. Here, we describe a pathway through which sustained, extended exposure to E2 signals down-regulation of BCRP at the blood-brain barrier. Six-hour exposure of isolated rat and mouse brain capillaries to E2 reduced BCRP transport activity and BCRP monomer and dimer expression. Experiments with brain capillaries from estrogen receptor (ER)alpha and ERbeta knockout mice and with ER agonists and antagonists showed that E2 signaled through ERbeta to down-regulate BCRP expression. In rat brain capillaries, E2 increased unphosphorylated, active phosphatase and tensin homolog (PTEN); decreased phosphorylated, active Akt; and increased phosphorylated, active glycogen synthase kinase (GSK)3. Consistent with this, inhibition of phosphoinositide 3-kinase (PI3K) or Akt decreased BCRP activity and protein expression, and inhibition of PTEN or GSK3 reversed the E2 effect on BCRP. Lactacystin, a proteasome inhibitor, abolished E2-mediated BCRP down-regulation, suggesting internalization followed by transporter degradation. Dosing mice with E2 reduced BCRP activity in brain capillaries within 1 h; this reduction persisted for 24 h. BCRP protein expression in brain capillaries was unchanged 1 h after E2 dosing but was substantially reduced 6 and 24 h after dosing. Thus, E2 signals through ERbeta, PTEN/PI3K/Akt/GSK3 to stimulate proteasomal degradation of BCRP. These in vitro and in vivo findings imply that E2-mediated down-regulation of blood-brain barrier BCRP has the potential to increase brain uptake of chemotherapeutics that are BCRP substrates.

Antiviral therapy with entecavir combined with post-exposure "prime-boost" vaccination eliminates duck hepatitis B virus-infected hepatocytes and prevents the development of persistent infection.

Short-term antiviral therapy with the nucleoside analogue entecavir (ETV), given at an early stage of duck hepatitis B virus (DHBV) infection, restricts virus spread and leads to clearance of DHBV-infected hepatocytes in approximately 50% of ETV-treated ducks, whereas widespread and persistent DHBV infection develops in 100% of untreated ducks. To increase the treatment response rate, ETV treatment was combined in the current study with a post-exposure "prime-boost" vaccination protocol. Four groups of 14-day-old ducks were inoculated intravenously with a dose of DHBV previously shown to induce persistent DHBV infection. One hour post-infection (p.i.), ducks were primed with DNA vaccines that expressed DHBV core (DHBc) and surface (pre-S/S and S) antigens (Groups A, B) or the DNA vector alone (Groups C, D). ETV (Groups A, C) or water (Groups B, D) was simultaneously administered by gavage and continued for 14 days. Ducks were boosted 7 days p.i. with recombinant fowlpoxvirus (rFPV) strains also expressing DHBc and pre-S/S antigens (Groups A, B) or the FPV-M3 vector (Groups C, D). DHBV-infected hepatocytes were observed in the liver of all ducks at day 4 p.i. with reduced numbers in the ETV-treated ducks. Ducks treated with ETV plus the control vectors showed restricted spread of DHBV infection during ETV treatment, but in 60% of cases, infection became widespread after ETV was stopped. In contrast, at 14 and 67 days p.i., 100% of ducks treated with ETV and "prime-boost" vaccination had no detectable DHBV-infected hepatocytes and had cleared the DHBV infection. These findings suggest that ETV treatment combined with post-exposure "prime-boost" vaccination induced immune responses that eliminated DHBV-infected hepatocytes and prevented the development of persistent DHBV infection.

Nucleoside phosphonate interactions with multiple organic anion transporters in renal proximal tubule.

The interactions of two antiviral, acyclic nucleoside phosphonates, adefovir and cidofovir, with xenobiotic transporters was studied in intact killifish (Fundulus heteroclitus) renal proximal tubules by using fluorescent substrates, confocal microscopy, and quantitative image analysis. Both drugs reduced in a concentration-dependent manner the transport of fluorescein on the classical organic anion system and transport of fluorescein-methotrexate on multidrug resistance-associated protein 2 (Mrp2). Neither drug inhibited transport of a fluorescent cyclosporin A derivative on P-glycoprotein. Inhibition of Mrp2-mediated transport was abolished by 50 microM p-aminohippurate, indicating that adefovir and cidofovir entered the cells at the basolateral membrane on the classical organic anion transport system (OAT1). Comparison of the inhibitory potencies of the nucleoside phosphonates with other substrates and inhibitors showed them to be moderate inhibitors of OAT1- and Mrp2-mediated transport.

Germline BRCA1-2 mutations in non-Ashkenazi families with double primary breast and ovarian cancer.

OBJECTIVE: Ashkenazi women with double primary breast and ovarian cancer have a high prevalence (57%) of germline Jewish founder mutations in the BRCA1 (185delAG, 5382insC) and BRCA2 (6174delT) genes. The purpose of this study was to determine the frequency and type of BRCA1-2 mutations in non-Ashkenazi families with at least one member having double primary breast and ovarian cancer. METHODS: Women at increased risk for cancer based upon their family history were enrolled at the University of Texas Southwestern Familial Cancer Registry between 1992 and 2000. Blood samples from patients desiring genetic testing were sent for complete DNA sequencing of the BRCA1 and BRCA2 genes. Families with a member having both breast and ovarian cancer were identified and clinical data were obtained. RESULTS: Sixty-two (7%) of 900 enrolled families were non-Ashkenazi and had at least one member with double primary breast and ovarian cancer. Twenty-one families had members who underwent genetic testing; 41 did not. Thirteen (62%) families had a germline BRCA1 (n = 11) or BRCA2 (n = 2) mutation; only one Jewish founder mutation (185delAG) was detected. Eight (38%) families tested negative. Six (86%) of seven women undergoing genetic testing who themselves had double primary breast and ovarian cancer were BRCA1-2 mutation carriers. CONCLUSIONS: Germline BRCA1-2 mutations are common in non-Ashkenazi families with a member having double primary breast and ovarian cancer. These mutations occurred throughout both genes, emphasizing the need for comprehensive sequencing. One family had the BRCA2 6985delCT mutation, which lies beyond the "ovarian cancer cluster" region.

Ventricular choline transport: a role for organic cation transporter 2 expressed in choroid plexus.

To determine whether organic cation transporter (OCT) family members might mediate choline transport in choroid plexus (CP), the handling of choline by cloned transporters and by intact CP isolated from the adult rat was investigated. Expression of OCT1 and OCT2 in Xenopus oocytes increased hemicholinium-3-sensitive choline uptake. In contrast, OCT3 did not mediate choline transport. Estimated K(m) values for choline in rOCT1-, rOCT2-, and hOCT2-expressing oocytes were 346 +/- 50, 441 +/- 67, and 102 +/- 80 microm, respectively. Membrane potential was the major driving force for choline uptake in rat and human OCT2-expressing oocytes and in intact CP in vitro. Lowering of medium pH (6 versus 7.4) was equally effective at inhibiting choline uptake in CP, suggesting that there might be a non-OCT component of choline uptake that is responsive to an H(+) gradient. However, choline efflux from CP was not stimulated by a trans-applied H(+) gradient. Choline uptake by CP was Na(+)-independent with an estimated K(m) of 183 microm. Reverse transcriptase-polymerase chain reaction detected OCT2 and OCT3, but not OCT1, mRNA expression in CP. Transfection of intact CP with a rOCT2/green fluorescent protein fusion construct resulted in strong apical membrane fluorescence with no detectable signal in the basal and lateral plasma membranes. These data indicate that OCT2 mediates choline transport across the ventricular membrane of CP.

Impact of maintenance ECT on concentration and memory.

INTRODUCTION: With the increased administration of outpatient electroconvulsive therapy (ECT), it is important to develop methods for monitoring patients for adverse effects of treatment. This pilot study was designed to evaluate the utility of using telephone assessments to determine whether patents receiving maintenance ECT (MECT) experience cognitive deficits related to individual treatments. METHOD: Patients were recruited from an existing population of outpatients receiving MECT. The consenting patients were called on three occasions and given a battery of telephone cognitive assessments including Orientation-Memory-Concentration, Buschke Selective Reminding, Verbal Fluency, "World" Backwards, Serial Sevens, and Wechsler Logical Memory. The occasions for the telephone interviews were the day before ECT, the day after a treatment, and a week later. RESULTS: Sixteen patients completed the study. The correlation between baseline and time 3 ranged from 1.00 for spelling "world" backward to 0.509 for Verbal Fluency Category, indicating considerable variability in test-retest reliability. One test, Verbal Fluency Category, showed group level effects, with decrements in performance the day after a treatment. One of the 16 patients showed global cognitive deficits the day after a treatment. DISCUSSION: The pilot results suggest that telephone assessment may be a useful approach for monitoring patients receiving outpatient ECT. Monitoring may serve to guide clinicians in advising individuals and their caregivers about the return to activities after an individual treatment. Overall these findings support the tolerability of MECT.

Overexpression of glutathione S-transferase II and multidrug resistance transport proteins is associated with acquired tolerance to inorganic arsenic.

Recent work shows that long-term exposure to low levels of arsenite induces malignant transformation in a rat liver epithelial cell line. Importantly, these chronic arsenic-exposed (CAsE) cells also develop self-tolerance to acute arsenic exposure. Tolerance is accompanied by reduced cellular arsenic accumulation, suggesting a mechanistic basis for reduced arsenic sensitivity. The present study examined the role of xenobiotic export pumps in acquired arsenic tolerance. Microarray analysis of CAsE cells showed increased expression of the genes encoding for glutathione S-transferase Pi (GST-Pi), multidrug resistance-associated protein genes (MRP1/MRP2, which encode for the efflux transporter Mrp1/Mrp2) and the multidrug resistance gene (MDR1, which encodes for the efflux transporter P-glycoprotein). These findings were confirmed at the transcription level by reverse transcription-polymerase chain reaction and at the translation level by Western-blot analysis. Acquired arsenic tolerance was abolished when cells were exposed to ethacrynic acid (an inhibitor of GST-Pi), buthionine sulfoximine (a glutathione synthesis inhibitor), MK571 (a specific inhibitor for Mrps), and PSC833 (a specific inhibitor for P-glycoprotein) in dose-dependent fashions. MK571, PSC833, and buthionine sulfoximine markedly increased cellular arsenic accumulation. Consistent with a role for multidrug resistance efflux pumps in arsenic resistance, CAsE cells were found to be cross-resistant to cytotoxicity of several anticancer drugs, such as vinblastine, doxorubicin, actinomycin-D, and cisplatin, that are also substrates for Mrps and P-glycoprotein. Thus, acquired tolerance to arsenic is associated with increased expression GST-Pi, Mrp1/Mrp2 and P-glycoprotein, which function together to reduce cellular arsenic accumulation.

Nephrotoxicants induce endothelin release and signaling in renal proximal tubules: effect on drug efflux.

We previously used killifish proximal tubules, fluorescent substrates, and confocal microscopy to demonstrate that transport mediated by the multidrug resistance protein (Mrp2) and by P-glycoprotein was reduced by nanomolar concentrations of endothelin-1 (ET), acting through a basolateral B-type ET receptor and protein kinase C (PKC). Here we show that representatives of two classes of nephrotoxicants decrease transport by activating the endothelin-PKC signaling pathway. Exposing tubules to radiocontrast agents (iohexol, diatrizoate) or aminoglycoside antibiotics (gentamicin, amikacin) reduced Mrp2-mediated fluorescein methotrexate (FL-MTX) transport from cell to tubular lumen. Pretreating the tubules with an ET(B)-receptor antagonist or with PKC-selective inhibitors abolished these effects. The nephrotoxicants activated signaling by inducing release of ET from the tubules, because adding of an antibody against ET to the medium abolished the effects. Elevating medium Ca(2+) also reduced FL-MTX transport; this reduction was abolished when tubules were pretreated with an ET antibody, an ET(B)-receptor antagonist, PKC-selective inhibitors, or the Ca(2+) channel blocker, nifedipine. None of these drugs by themselves affected FL-MTX transport. Importantly, nifedipine also blocked the ET(B)-receptor/PKC-dependent reduction in FL-MTX transport caused by gentamicin and diatrizoate. These results for two classes of structurally unrelated nephrotoxicants suggest that Ca(2+)-dependent ET release and subsequent action through an autocrine mechanism may be an early response to tubular injury.

Optimum screening interventions for gynecologic malignancies.

The availability of screening modalities and improvements in prevention have reduced the risk of developing some cancers over the last few decades. Methods for optimal screening of gynecologic cancers are still being investigated. Cervical cancer is the only gynecologic malignancy for which a screening modality is widely accepted and recommended to all women. Annual screening of cervical cells has been shown to reduce the incidence of cervical cancer by 78%. Unfortunately, more than 50% of cervical cancers occur in women who have not been screened optimally. In the year 2000, an estimated 12,800 women developed cervical cancer. Of these women, 89% were seen by a physician but not screened. Vaginal cancer is associated with a similar etiology, pathobiology, and symptomatology as is cervical cancer. Vaginal dysplasia and cancer can also be detected by the Pap test, but the prevalence of the disease is low. Endometrial carcinoma is the most common gynecologic cancer. The widespread availability of outpatient biopsy devices has been the most significant advance in the early diagnosis of corpus cancers. Ovarian cancer is the gynecologic malignancy associated with the highest death rate. No modality has been shown as an effective screening method for this cancer. Women with a family history of ovarian cancer may benefit from combined modality screening; prophylactic oophorectomy should be offered to those with hereditary ovarian cancer syndromes. A complete physical examination by the physician offers the best method for early detection of vulvar cancer. Awareness and implementation of recommended screening guidelines for gynecologic cancers by primary care and specialty physicians can decrease the incidence and mortality of cervical cancer. Including the genital tract in the complete examination of the female patient could decrease markedly the mortality from the other gynecologic cancers.

Prostate carcinoma knowledge, attitudes, and screening behavior among African-American men in Central Harlem, New York City.

BACKGROUND: Although the benefits of prostate carcinoma screening in reducing mortality rates have not been proven or shown to be cost-effective, screening, particularly using prostate specific antigen (PSA) tests, is widespread. A better understanding of screening behavior, knowledge of prostate carcinoma risk, and attitudes toward screening among men at high risk, such as African-American men, would be valuable. METHODS: A prevalence survey was conducted using 2 samples of African-American men, aged 50-74 years: a clinic sample drawn from all clinics in Central Harlem (n = 404) and a random-digit dial sample from the same geographic region (n = 319). The prevalence of self-reported PSA screening was estimated using a cognitive survey methodology based on the internal consistency of answers to four different questions. Prevalence estimates were adjusted to take into account the high proportion of nontelephone residences. RESULTS: The clinic sample, representing a poorer, more ill population (as determined by MOS Physical Function Scores, was less likely to report PSA screening than the community sample (11.1% in clinic sample vs. 25.5% in community). The prevalence of PSA testing in Central Harlem overall in this age group by using two different techniques was estimated to be 24%. In multiple logistic models, self-reported PSA screening was associated with age, education, favorable attitudes toward screening, and knowing someone who had prostate carcinoma. However, the association between these factors and the likelihood of self-reported PSA screening differed between clinic and community samples. CONCLUSIONS: The prevalence of self-reported PSA screening in Central Harlem was lower than that reported for other populations. These findings may be useful in the design of health education campaigns and for counseling innercity, low-income African-American patients appropriately about the disease.