Nanoscale transport of charge-transfer states in organic donor-acceptor blends.

Charge-transfer (CT) states, bound combinations of an electron and a hole on separate molecules, play a crucial role in organic optoelectronic devices. We report direct nanoscale imaging of the transport of long-lived CT states in molecular organic donor-acceptor blends, which demonstrates that the bound electron-hole pairs that form the CT states move geminately over distances of 5-10 nm, driven by energetic disorder and diffusion to lower energy sites. Magnetic field dependence reveals a fluctuating exchange splitting, indicative of a variation in electron-hole spacing during diffusion. The results suggest that the electron-hole pair of the CT state undergoes a stretching transport mechanism analogous to an 'inchworm' motion, in contrast to conventional transport of Frenkel excitons. Given the short exciton lifetimes characteristic of bulk heterojunction organic solar cells, this work confirms the potential importance of CT state transport, suggesting that CT states are likely to diffuse farther than Frenkel excitons in many donor-acceptor blends.

Differential degradation of motor deficits during gradual dopamine depletion with 6-hydroxydopamine in mice.

Parkinson's disease (PD) is a movement disorder whose cardinal motor symptoms arise due to the progressive loss of dopamine. Although this dopamine loss typically progresses slowly over time, currently there are very few animal models that enable incremental dopamine depletion over time within the same animal. This type of gradual dopamine depletion model would be useful in studies aimed at the prodromal phase of PD, when dopamine levels are pathologically low but motor symptoms have not yet presented. Utilizing the highly characterized neurotoxin 6-hydroxydopamine (6-OHDA), we have developed a paradigm to gradually deplete dopamine levels in the striatum over a user-defined time course - spanning weeks to months - in C57BL/6 mice. Dopamine depletions were achieved by administration of five low-dose injections (0.75µg) of 6-OHDA through an implanted intracranial bilateral cannula targeting the medial forebrain bundle. Levels of dopamine within the striatum declined linearly with successive injections, quantified using tyrosine hydroxylase immunostaining and high-performance liquid chromatography. Behavioral testing was carried out at each time point to study the onset and progression of motor impairments as a function of dopamine loss over time. We found that spontaneous locomotion, measured in an open field, was robust until ∼70% of striatal dopamine was lost. Beyond this point, additional dopamine loss caused a sharp decline in motor performance, reaching a final level comparable to that of acutely depleted mice. Similarly, although rearing behavior was more sensitive to dopamine loss and declined linearly as a function of dopamine levels, it eventually declined to levels similar to those seen in acutely depleted mice. In contrast, motor coordination, measured on a vertical pole task, was only moderately impaired in gradually depleted mice, despite severe impairments observed in acutely depleted mice. These results demonstrate the importance of the temporal profile of dopamine loss on the magnitude and progression of behavioral impairments. Our gradual depletion model thus establishes a new paradigm with which to study how circuits respond and adapt to dopamine loss over time, information which could uncover important cellular events during the prodromal phase of PD that ultimately impact the presentation or treatability of behavioral symptoms.

Emergency interventions for hyperkalaemia

It brings information about the hyperkalaemia, its incidence, consequences and treatment by using emergency interventions.

Radiotherapy plus chemotherapy with or without surgical resection for stage III non-small-cell lung cancer: a phase III randomised controlled trial.

BACKGROUND: Results from phase II studies in patients with stage IIIA non-small-cell lung cancer with ipsilateral mediastinal nodal metastases (N2) have shown the feasibility of resection after concurrent chemotherapy and radiotherapy with promising rates of survival. We therefore did this phase III trial to compare concurrent chemotherapy and radiotherapy followed by resection with standard concurrent chemotherapy and definitive radiotherapy without resection. METHODS: Patients with stage T1-3pN2M0 non-small-cell lung cancer were randomly assigned in a 1:1 ratio to concurrent induction chemotherapy (two cycles of cisplatin [50 mg/m(2) on days 1, 8, 29, and 36] and etoposide [50 mg/m(2) on days 1-5 and 29-33]) plus radiotherapy (45 Gy) in multiple academic and community hospitals. If no progression, patients in group 1 underwent resection and those in group 2 continued radiotherapy uninterrupted up to 61 Gy. Two additional cycles of cisplatin and etoposide were given in both groups. The primary endpoint was overall survival (OS). Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00002550. FINDINGS: 202 patients (median age 59 years, range 31-77) were assigned to group 1 and 194 (61 years, 32-78) to group 2. Median OS was 23.6 months (IQR 9.0-not reached) in group 1 versus 22.2 months (9.4-52.7) in group 2 (hazard ratio [HR] 0.87 [0.70-1.10]; p=0.24). Number of patients alive at 5 years was 37 (point estimate 27%) in group 1 and 24 (point estimate 20%) in group 2 (odds ratio 0.63 [0.36-1.10]; p=0.10). With N0 status at thoracotomy, the median OS was 34.4 months (IQR 15.7-not reached; 19 [point estimate 41%] patients alive at 5 years). Progression-free survival (PFS) was better in group 1 than in group 2, median 12.8 months (5.3-42.2) vs 10.5 months (4.8-20.6), HR 0.77 [0.62-0.96]; p=0.017); the number of patients without disease progression at 5 years was 32 (point estimate 22%) versus 13 (point estimate 11%), respectively. Neutropenia and oesophagitis were the main grade 3 or 4 toxicities associated with chemotherapy plus radiotherapy in group 1 (77 [38%] and 20 [10%], respectively) and group 2 (80 [41%] and 44 [23%], respectively). In group 1, 16 (8%) deaths were treatment related versus four (2%) in group 2. In an exploratory analysis, OS was improved for patients who underwent lobectomy, but not pneumonectomy, versus chemotherapy plus radiotherapy. INTERPRETATION: Chemotherapy plus radiotherapy with or without resection (preferably lobectomy) are options for patients with stage IIIA(N2) non-small-cell lung cancer. FUNDING: National Cancer Institute, Canadian Cancer Society, and National Cancer Institute of Canada.

A comparison of self-report and caregiver assessment of depression, apathy, and irritability in Huntington's disease.

The natural history of psychiatric syndromes associated with Huntington's disease (HD) remains unclear, and longitudinal studies of symptoms such as depression, apathy, and irritability are required to better understand the progression and role of these syndromes and their effect on disability. Self-administered scales such as the Beck Depression Inventory (BDI) may be useful to document changes in symptoms over time, but the validity of self-report may be questionable with the inevitable progression of cognitive deficits. An alternative to the patient's self-report would be assessments by the caregiver. The authors assessed interrater agreement between patient self-assessment and caregiver assessment of patients status for the presence of depressed mood using the BDI and apathy and irritability using an apathy and irritability scale. Agreement between these scales across strata of cognitive status was also examined. Interrater agreement varied from moderate to good for the BDI, depending on patient cognitive status. Agreement for the apathy scores was low for patients with poor cognition and fair in patients with better cognition. Irritability scale agreement was fair at best and was the worst in patients with the most intact cognition. Caregiver assessment of patients' moods and apathy may be an acceptable alternative to patient self-report as patients' cognitive status worsens.

Distribution of human papillomavirus types 16 and 18 variants in squamous cell carcinomas and adenocarcinomas of the cervix.

The distributions of human papillomavirus (HPV) types detected in cervical adenocarcinomas and squamous cell tumors differ. However, whether the distributions of intratypic HPV variants seen in these two histological forms of cervical disease differ is unknown. Our objective was to compare the distribution of HPV intratypic variants observed in squamous cell carcinomas (SCC) and cervical tumors of glandular origin (e.g., adenocarcinomas; AC) for two HPV types commonly observed in cervical tumors, HPV16 and HPV18. Participants in a multicenter case-control study of AC and SCC conducted in the eastern United States were studied. A total of 85 HPV16 and/or HPV18 positive individuals (31 diagnosed with AC, 43 diagnosed with SCC, and 11 population controls) were included. For HPV16-positive individuals, both the noncoding long control region and the E6 open reading frame were sequenced, and classified into phylogenetic-based lineage groups (European, Asian-American, African1, and African2). For HPV18-positive individuals, the long control region region only was sequenced and classified into known intratypic lineages (European, Asian-Amerindian, and African). The distribution of these different intratypic lineages among AC cases, SCC cases, and population controls was compared using standard methods. Non-European HPV16 and/or HPV18 intratypic variants were observed in 42% of ACs compared with 16% of SCCs and 18% of population controls (P = 0.04). Intratypic variants from the Asian-American lineage of HPV16 accounted for the differences seen between histological groups. The differences observed between AC and SCC cases were strongest for HPV16, and persisted in analysis restricted to Caucasian women, suggesting that the effect cannot be explained by differences in the ethnic make-up of AC versus SCC cases. Cervical AC and SCC differ not only with respect to the distribution of HPV types detected but also with respect to intratypic variants observed. Non-European HPV16 and/or HPV18 variants are commonly seen in AC. A possible hormonal mechanism is suggested to explain the observed findings.

Obesity as a potential risk factor for adenocarcinomas and squamous cell carcinomas of the uterine cervix.

BACKGROUND: Hormonal factors may play a more prominent role in cervical adenocarcinoma than squamous cell carcinoma. The authors evaluated whether obesity, which can influence hormone levels, was associated with adenocarcinoma and squamous cell carcinoma. METHODS: This case-control study included 124 patients with adenocarcinoma, 139 matched patients with squamous cell carcinoma, and 307 matched community control participants. All participants completed interviews and provided cervicovaginal samples for human papillomavirus (HPV) testing. Polytomous logistic regression-generated odds ratios (ORs) and 95% confidence intervals (95% CIs) for self-reported height and weight, body mass index (BMI; kg/m(2)), and measured waist-to-hip ratio (WHR) for both histologic types were adjusted and stratified for HPV and other confounders. RESULTS: Height, weight, BMI, and WHR were positively associated with adenocarcinoma. BMI >or= 30 kg/m(2) (vs. BMI < 25 kg/m(2); OR, 2.1 and 95% CI, 1.1-3.8) and WHR in the highest tertile (vs. the lowest tertile; OR, 1.8 and 95% CI, 0.97-3.3) were associated with adenocarcinoma. Neither height nor weight was found to be associated with squamous cell carcinoma, and associations for BMI >or= 30 kg/m(2) (OR, 1.6) and WHR in the highest tertile (OR, 1.6) were weaker and were not statistically significant. Analyses using only HPV positive controls showed similar associations. The data were adjusted for and stratified by screening, but higher BMI and WHR were associated with higher disease stage at diagnosis, even among recently and frequently screened patients with adenocarcinoma. Thus, residual confounding by screening could not be excluded as an explanation for the associations. CONCLUSIONS: Obesity and body fat distribution were associated more strongly with adenocarcinoma than with squamous cell carcinoma. Although questions about screening remain, obesity may have a particular influence on the risk of glandular cervical carcinoma.

Comparison of human papillomavirus genotypes, sexual, and reproductive risk factors of cervical adenocarcinoma and squamous cell carcinoma: Northeastern United States.

OBJECTIVE: Although human papillomavirus causes essentially all cervical carcinoma, cofactors may differ by cancer histologic type. We examined human papillomavirus genotypes and sexual and reproductive risk factors for cervical adenocarcinoma and squamous cell carcinoma. STUDY DESIGN: One hundred twenty-four women with adenocarcinoma, 139 women with squamous cell carcinoma, and 307 control subjects participated in this case-control study. Logistic regression analyses were performed to calculate odds ratios and CIs. RESULTS: Human papillomavirus 18 was associated most strongly with adenocarcinoma (odds ratio, 105; 95% CI, 23-487). Human papillomavirus 16 was associated most strongly with squamous cell carcinoma (odds ratio, 30; 95% CI, 12-77). More than three lifetime sexual partners was a risk factor for adenocarcinoma (odds ratio, 2.1; 95% CI, 1.1-4.0) and squamous cell carcinoma (odds ratio, 3.0; 95% CI, 1.6-5.9). Even being pregnant was associated inversely with adenocarcinoma (odds ratio, 0.4; 95% CI, 0.2-0.8). Five or more pregnancies was associated with squamous cell carcinoma (odds ratio, 2.2; 95% CI, 0.9-5.4). CONCLUSION: The relative importance of human papillomavirus genotypes 16 and 18 and the reproductive co-factor differences suggest distinct causes for cervical adenocarcinoma and squamous cell carcinoma.

Comprehensive analysis of human leukocyte antigen class I alleles and cervical neoplasia in 3 epidemiologic studies.

To comprehensively explore the relationship between human leukocyte antigen (HLA) class I alleles and cervical neoplasia, a subset of participants from 3 large US and Costa Rican cervix studies were typed for HLA class I alleles. Study subjects were women with cervical cancer or high-grade squamous epithelial lesions (HSILs; n=365) or low-grade squamous epithelial lesions (LSILs; n=275) or who were cytologically normal (control subjects; n=681). Allele-disease associations were assessed by logistic regression analysis. Consistent associations across all studies were observed for HLA-CW*0202 with a combined odds ratio of 0.53 (95% confidence interval [CI], 0.29-0.89) for cancer or HSILs and 0.58 (95% CI, 0.37-1.04) for LSILs, compared with control subjects and adjusted for study. This finding supports the hypothesis that a single allele may be sufficient to confer protection against cervical neoplasia. Given the relationship between HLA-C and its receptors on natural killer (NK) cells, a role is proposed for NK function in human papillomavirus infection and cervical neoplasia.

Intraoperative sentinel lymph node mapping in non-small-cell lung cancer improves detection of micrometastases.

PURPOSE: Lymph node metastases are the most significant prognostic factor in localized non-small-cell lung cancer (NSCLC). Nodal micrometastases may not be detected with current standard histologic methods. We performed intraoperative technetium-99m ((99m)Tc) sentinel lymph node (SN) mapping in patients with resectable NSCLC. This study aimed to identify the first station of nodal drainage of operable lung cancers. Serial section histology and immunohistochemistry were used to validate the SN and to identify the presence of micrometastatic disease. PATIENTS AND METHODS: One hundred patients with potentially resectable suspected NSCLC were enrolled. At thoracotomy, the primary tumor was injected with 0.25 to 2 mCi (99m)Tc. Intraoperative scintigraphic readings of both the primary tumor and lymph nodes were obtained with a hand-held gamma counter. Anatomic resection with a mediastinal node dissection was then performed. RESULTS: Nine of the 100 patients did not have NSCLC (seven benign lesions and two metastatic tumors) and were excluded. Seventy-eight (86%) of 91 patients had a SN identified and a complete resection. Sixty-nine (88.5%) out of the 78 SNs were classified as true-positive with no metastases found in other intrathoracic lymph nodes without concurrent SN involvement. In nine patients, the SN was the only positive node. In seven of these nine patients, the SN was found to harbor only micrometastatic disease. CONCLUSION: Intraoperative SN mapping with (99m)Tc is an accurate way to identify the first site of lymphatic tumor drainage in NSCLC. This method may also improve the precision of pathologic staging.

Detection and quantitation of human papillomavirus DNA in the plasma of patients with cervical carcinoma.

Human papillomaviruses (HPVs) play a central role in the development of cervical carcinoma. Plasma DNA from 232 patients taken at diagnosis or after treatment for invasive cervical cancer (n = 175) or carcinoma in situ (n = 57) and 60 normal controls were examined for HPV-16 or HPV-18 E7 DNA by conventional and real-time quantitative PCR assays. We found HPV-16 or HPV-18 E7 DNA in 6.9% (11 of 175) of invasive cervical cancer cases (18.1% of cases positive for HPV-16 or HPV-18 at the genital tract), 1.8% (1 of 57) of carcinoma in situ, and 1.7% (1 of 60) of normal controls by conventional PCR. Quantitative PCR identified the highest concentrations of HPV DNA (copy number of HPV/ml of plasma) in patients with invasive cervical cancer (mean, 11,163; median, 183.5), followed by a level of 8 in the single carcinoma in situ case and 0 copies in the normal control initially positive by conventional PCR. HPV DNA can be detected in the plasma of some patients with HPV-positive cervical tumors. It remains to be demonstrated whether quantitative PCR analysis of HPV DNA in plasma may have utility in patients at high risk of recurrent disease.

The effect of aromatase inhibition on sex steroids, gonadotropins, and markers of bone turnover in older men.

There is evidence that estrogen decreases bone turnover in men as well as women. We therefore hypothesized that older men would show increased bone resorption in response to inhibition of the aromatase enzyme, which converts androgens to estrogen. Fifteen eugonadal men over 65 yr were treated for 9 weeks with 2.0 mg/day of anastrozole, an aromatase inhibitor. After 9 weeks of treatment, there were significant decreases in estradiol, estrone, and sex hormone-binding globulin levels by 29%, 73%, and 16%, respectively, and total testosterone increased significantly by 56%. Despite the limited decrease of estrogen and the increase in testosterone, C-telopeptide of type 1 collagen showed a progressive significant increase of 11%, 24%, and 33% (P for trend = 0.033) above baseline at 3, 6, and 9 weeks, respectively. N-telopeptide of type 1 collagen values were highly correlated with C-telopeptide of type 1 collagen, but the change in N-telopeptide of type 1 collagen was not statistically significant. Bone-specific alkaline phosphatase and N-terminal type I procollagen peptides showed significant decreases of 8% and 11% of baseline at 9 weeks. Osteocalcin decreased significantly by 30% at 18 weeks. We conclude that aromatase inhibition can reduce estrogen levels in older men, but this effect is limited, perhaps because of feedback stimulation of testosterone production, and that endogenous estrogen derived from aromatization of testosterone plays a role in bone metabolism of older men by limiting the rate of bone resorption.

Effect of norethindrone acetate on hormone levels and markers of bone turnover in estrogen-treated postmenopausal women.

There is controversy concerning the effects of progestins on bone. Norethindrone acetate (NETA) is synthetic progesterone that also has estrogenic and androgenic effects. We tested its effects on hormone levels, lipids and biochemical markers of bone turnover in postmenopausal women who were on estrogen replacement therapy. Women were treated with NETA, 5 mg/d for 9 weeks. Estrogenic effects included a marked lowering of follicle stimulating hormone and luteinizing hormone. Androgenic effects included a decrease in sex hormone binding globulin and HDL cholesterol. Bone turnover showed inconsistent responses. Among markers of bone formation, bone specific alkaline phosphatase decreased significantly by 23% while procollagen peptides and osteocalcin showed a non-significant increase. The marker of bone resorption, N-telopeptide crosslinks of collagen, decreased by 19% at 6 weeks. These results indicate that NETA does not have a potent short-term anabolic effect on bone but does have effects that are likely to be mediated through the estrogen and androgen receptors.

The effect of short-term treatment with micronized estradiol on bone turnover and gonadotrophins in older men.

Evidence for the role of estrogen in male bone metabolism has been confirmed by studies on a man with a genetic defect in the estrogen receptor as well as men with aromatase defects. All exhibited tall stature, delayed epiphysial closure, decreased bone density and increased bone turnover. Estrogen is likely to affect bone turnover in men throughout life; therefore, we hypothesized that older men would show decreased bone resorption in response to estrogen therapy. To test our hypothesis, fourteen community-dwelling men with osteopenia of the femoral neck were treated for 9 weeks with micronized estradiol, 1 mg/d, a dose which is effective in postmenopausal women. Each subject served as his own control. Markers of bone resorption, N-terminal collagen crosslinks (NTX) and C-terminal collagen crosslinks (CTX) and markers of bone formation, osteocalcin (OC) and bone specific alkaline phosphatase (BSAP) were measured every 3 weeks during a 9-week treatment period and 9 weeks post-treatment. Sex hormones, gonadotrophins and calciotropic hormones were measured at baseline, 9 weeks on treatment and 9 weeks post- treatment. After 9 weeks of treatment, estradiol and estrone levels increased significantly by greater than 6-fold and 15-fold, respectively. SHBG levels increased significantly by 17%. Testosterone and free testosterone levels decreased significantly by 27% and 34%, respectively. Markers of bone resorption showed wide variation at baseline and while on treatment. There was no correlation between changes in bone markers and changes in estrogen levels. During treatment, 11 patients showed a decrease of NTX or CTX, but three showed an increase. These three and one other subject had high initial levels of FSH and LH, suggesting some degree of primary gonadal failure, which decreased during estrogen therapy. Thus, the change in NTX (and CTX) after 9 weeks of E2 treatment was correlated with initial FSH (r= -.66, p= .01) and LH (r= -.73, p= .003) values. In addition, the largest decrease in free testosterone at 9 weeks was correlated with the higher values for NTX, CTX and BAP (r=-0.66, -0.68, -0.70 respectively; p< or =.01 for each of the markers). Treatment was generally well tolerated. Side effects of treatment were minimal, and included breast tenderness and decreased libido which reversed after treatment. We conclude that it is feasible to give low dose estrogen to healthy older men, but that the effects on bone turnover are not consistent. Changes in central feedback and in endogenous sex hormone production may alter the response of bone turnover to exogenous estrogen in this population.

Mood and alcohol consumption: an experience sampling test of the self-medication hypothesis.

In this investigation the authors applied the experience sampling method to prospectively test the self-medication hypothesis. In vivo reports gathered in the context of daily life demonstrated that nervousness was the only negative mood state to predict increases in alcohol consumption later in the course of the day. Further examination of this within-person relationship demonstrated that men were more likely to consume alcohol when nervous than were women, but this association was unrelated to family history of alcoholism, problem drinking patterns, or trait anxiety and depression. Consistent with the self-medication hypothesis, cross-sectional analyses also confirmed that alcohol consumption was generally associated with lower levels of nervousness; this effect varied by several demographic and clinical variables. These findings are discussed in terms of the diversity of reasons for alcohol consumption and their potential for explaining problem drinking.

Mood states associated with transitory changes in asthma symptoms and peak expiratory flow.

OBJECTIVE: This study examined the within-person relations between transitory changes in mood, asthma symptoms, and peak expiratory flow rate (PEFR). METHODS: Thrice-daily for 21 consecutive days, 48 adults with moderate to severe asthma entered information in palm-top computers about their mood and asthma symptoms. A multidimensional model of mood, ie, the mood circumplex, informed the assessment of mood arousal and mood pleasantness. At each observation, participants also recorded their PEFR with peak flow meters that stored blinded data. Albuterol doses were also monitored electronically. Before and after the 21-day study, spirometric measures of airways obstruction were taken under controlled conditions. RESULTS: Random effects regression models revealed a significant, but weak, within-person relation between symptoms and PEFR. Changes in mood vectors with an arousal component were significantly related to PEFR changes, whereas changes in mood vectors with a pleasantness component tracked changes in asthma symptom reports, even after adjustment for contemporaneous PEFR and after controlling for time of day and albuterol dosing. Comparison of spirometric assessments with unsupervised PEFR suggested that part of the relation between mood arousal and PEFR may be attributable to the "effort-dependence" of peak flow self-monitoring. CONCLUSIONS: Different dimensions of mood were associated with transitory changes in asthma symptoms and PEFR. This may be one reason why individuals with asthma misperceive the severity of their symptoms in relation to underlying airways obstruction.

Upregulation of calcium homeostatic mechanisms in chronically depolarized rat myenteric neurons.

Perturbations of intracellular Ca2+ ion concentration ([Ca2+]i) have important effects on numerous neuronal processes and influence development and survival. Neuronal [Ca2+]i is, in large part, dependent on activity, and changes in activity levels can alter how neurons handle calcium (Ca). To investigate the ability of neuronal Ca homeostatic mechanisms to adapt to the persistent elevation of [Ca2+]i, we used optical and electrophysiological recording techniques to measure [Ca2+]i transients in neurons from the rat myenteric plexus that had been chronically depolarized by growth in culture medium containing elevated (25 mM) KCl. When studied in normal saline, neurons that had previously been chronically depolarized for 3-5 days had briefer action potentials than control neurons, their action potentials produced smaller, more rapidly decaying increases in [Ca2+]i, and voltage-clamp pulses with action potential waveforms evoked smaller Ca currents than in control neurons. Simultaneous voltage-clamp measurements and calcium imaging revealed that increases in the Ca handling capacities of the chronically depolarized neurons permitted them to limit the amplitudes of action potential-evoked [Ca2+]i transients and to restore [Ca2+]i to basal levels more rapidly than control neurons. Release of Ca from endoplasmic reticulum-based Ca stores made smaller contributions to action potential-evoked [Ca2+]i transients in chronically depolarized neurons even though those neurons had larger caffeine-releasable Ca stores. Endoplasmic reticulum-based Ca sequestration mechanisms appeared to contribute to the faster decay of [Ca2+]i transients in chronically depolarized neurons. These results demonstrate that when neurons experience prolonged perturbations of [Ca2+]i, they can adjust multiple components of their Ca homeostatic machinery. Appropriate utilization of this adaptive capability should help neurons resist potentially lethal metabolic and environmental insults.