Development and Evaluation of Brief Web-Based Education for Primary Care Providers to Address Inequities in Lung Cancer Screening and Smoking Cessation Treatment

Annual lung cancer screening (LCS) is recommended for individuals at high risk for lung cancer. However, primary care provider-initiated discussions about LCS and referrals for screening are low overall, particularly among Black or African Americans and other minoritized racial and ethnic groups. Disparities also exist in receiving provider advice to quit smoking. Effective methods are needed to improve provider knowledge about LCS and tobacco-related disparities, and to provide resources to achieve equity in LCS rates. We report the feasibility and impact of pairing a self-directed Lung Cancer Health Disparities (HD) Web-based course with the National Training Network Lung Cancer Screening (LuCa) course on primary care providers' knowledge about LCS and the health disparities associated with LCS. In a quasi-experimental study, primary care providers (N = 91) recruited from the MedStar Health System were assigned to complete the LuCa course only vs. the LuCa + HD courses. We measured pre-post-LCS-related knowledge and opinions about the courses. The majority (60.4%) of providers were resident physicians. There was no significant difference between groups on post-test knowledge (p > 0.05). However, within groups, there was an improvement in knowledge from pre- to post-test (LuCa only (p = 0.03); LuCa + HD (p < 0.001)). The majority of providers (81%) indicated they planned to improve their screening and preventive practices after having reviewed the educational modules. These findings provide preliminary evidence that this e-learning course can be used to educate providers on LCS, smoking cessation, and related disparities impacting patients.

Improved motivation and readiness to quit shortly after lung cancer screening: Evidence for a teachable moment

BACKGROUND

For patients at high risk for lung cancer, screening using low-dose computed tomography (lung cancer screening [LCS]) is recommended. The purpose of this study was to examine whether screening may serve as a teachable moment for smoking-related outcomes.

METHODS

In a smoking-cessation trial, participants (N = 843) completed 2 phone interviews before randomization: before LCS (T0) and after LCS (T1). By using logistic and linear regression, the authors examined teachable moment variables (perceived risk, lung cancer worry) and outcomes (readiness, motivation, and cigarettes per day [CPD]).

RESULTS

Participants were a mean ± SD age of 63.7 ± 5.9 years, had 47.8 ± 7.1 pack-years of smoking, 35.2% had a high school diploma or General Educational Development (high school equivalency) degree or less, and 42.3% were undergoing their first scan. Between T0 and T1, 25.7% of participants increased readiness to quit, 9.6% decreased readiness, and 64.7% reported no change (P < .001). Motivation to quit increased (P < .05) and CPD decreased between assessments (P < .001), but only 1.3% self-reported quitting. Compared with individuals who reported no lung cancer worry/little worry, extreme worry was associated with readiness to quit in the next 30 days (odds ratio, 1.8; 95% CI, 1.1-3.0) and with higher motivation (b = 0.83; P < .001) at T1. Individuals undergoing a baseline (vs annual) scan were more ready to quit in the next 30 days (odds ratio, 1.8; 95% CI, 1.3-2.5).

CONCLUSIONS

During the brief window between registering for LCS and receiving the results, the authors observed that very few participants quit smoking, but a significant proportion improved on readiness and motivation to quit, particularly among individuals who were undergoing their first scan and those who were extremely worried about lung cancer. These results indicate that providing evidence-based tobacco treatment can build upon this teachable moment.

Abstract PO-067: Developing provider education to address barriers and reduce disparities in lung cancer screening and smoking cessation treatment among underserved patients

Introduction: Lung cancer is a major public health problem in the US and disparities exist in lung cancer burden and lung cancer screening (LCS) utilization. African Americans (AA) have the highest lung cancer incidence and mortality compared to other racial and ethnic groups; however, LCS rates were lower among AAs compared to Whites under the 2013 United States Preventive Services Task Force (USPSTF) guidelines. While the expanded 2021 USPSTF criteria will significantly raise the number of AAs eligible for LCS, methods to increase rates of LCS among AA patients will still be needed. We describe the development of the first provider educational tool that focuses on barriers to reduce disparities in LCS. Methods: We completed qualitative interviews with primary care providers (N=9) and AA patients eligible for LCS (N=8; 4 screened, 4 unscreened) to assess barriers to LCS and tobacco cessation. Interviews were recorded and analyzed for common themes, which led to the development of the provider intervention. Results: Among patients, common barriers to LCS were a lack of information on the LCS procedure and associated costs, fear of the results, and transportation issues. Patient barriers to utilization of evidence-based cessation treatments included tobacco use stigma, cost of cessation aids, and inconsistent provider communication. Providers acknowledged time constraints during patient visits, lack of standardized training on documenting tobacco use, and the required LCS shared-decision making conversation as barriers to providing LCS referrals and cessation treatment. Both providers and patients noted that LCS rates may be increased by providing patient-facing information on the screening process and by facilitating provider referrals, which are essential for LCS. Based on these findings, we developed a self-directed 30-minute e-learning Health Disparities module that addresses: 1) disparities in the burden of lung cancer; 2) disparities in smoking patterns and utilization of evidence-based smoking cessation treatments; 3) patient barriers to LCS; and 4) resources for providers to address common LCS barriers (e.g., patient reminders to support scheduling the scan, offering transportation options). Experts in health disparities (N=6) and LCS (N=9) provided detailed critiques of the module content and presentation. Conclusions: We identified barriers to LCS and tobacco cessation from the perspectives of providers and AA patients. These findings informed the development of a brief web-based provider educational module to raise awareness about lung cancer and tobacco-related disparities and to provide resources to reduce barriers in diverse patient populations. We have begun a RCT to compare the Health Disparities module to an existing provider module on LCS to evaluate the impact on primary care providers' knowledge, attitudes, and LCS referrals of AA and White patients. These findings will provide preliminary evidence on provider education that can be easily disseminated to address health disparities in LCS and smoking cessation treatments.

Citation Format: Laney Smith, Daisy Dunlap, Randi Williams, Andrea Shepherd, Allison Windels, Maria Geronimo, Vicky Parikh, Chavalia J. Breece, Namita Puran, Eric Anderson, Lucile Adams-Campbell, Kathryn Taylor. Developing provider education to address barriers and reduce disparities in lung cancer screening and smoking cessation treatment among underserved patients [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-067.

Predictors of attrition in a smoking cessation trial conducted in the lung cancer screening setting

SIGNIFICANCE

Although it is a requirement that tobacco treatment is offered to cigarette smokers undergoing low-dose computed tomographic lung cancer screening (LCS), not all smokers engage in treatment. To understand the barriers to tobacco treatment in this setting, we evaluated predictors of attrition in a smoking cessation trial among individuals undergoing LCS.

METHODS

Prior to LCS, 926 participants, 50-80 years old, completed the baseline (T0) phone assessment, including demographic, clinical, tobacco, and psychological characteristics. Following LCS and receipt of the results, participants completed the pre-randomization (T1) assessment.

RESULTS

At the T1 assessment, 735 (79%) participants were retained and 191 (21%) dropped out. In multivariable analyses, attrition was higher among those who: smoked >1 pack per day (OR = 1.44, CI 1.01, 2.06) or had undergone their first (vs. annual) LCS scan (OR = 1.70, CI 1.20, 2.42). Attrition was lower among those with: more education (associates (OR = 0.67, CI = 0.46, 0.98) or bachelor's degree (OR = 0.56, CI 0.35, 0.91) vs. high school/GED), some (vs. none/a little) worry about lung cancer (OR = 0.60, CI 0.39, 0.92), or a screening result that was benign (OR = 0.57, CI 0.39, 0.82) or probably benign (OR = 0.38, CI 0.16, 0.90) vs. negative.

CONCLUSIONS

This study illuminated several LCS-related factors that contributed to trial attrition. Increasing tobacco treatment in this setting will require targeted strategies for those who report little lung cancer worry, are undergoing their first LCS exam, and/or who have a negative LCS result. Addressing attrition and reducing barriers to tobacco treatment will increase the likelihood of cessation, thereby reducing the risk of developing lung cancer.

“Clots and Failures” A Case of COVID-19 Causing STEMI and Persistent Cardiogenic Shock Ultimately Requiring LVAD

Introduction

We present a case of COVID-19 causing hypercoagulability and inflammatory stress leading to STEMI in a patient who went on to develop persistent cardiogenic shock requiring LVA) implantation.

Case Report

57-year-old lady developed COVID-19 infection in May 2020. In June 2020, she presented with chest pain, was noted to have STEMI on EKG, complicated by cardiac arrest with ROSC in 14 minutes. She was in cardiogenic shock as well and was started on veno-arterial ECMO. She underwent left anterior descending artery stent placement. Further hospitalization was complicated by persistent cardiogenic shock and complete heart block and underwent pacemaker and cardiac-defibrillator implantation. She developed pulmonary edema, acute kidney injury requiring hemodialysis, shock liver, and persistent cardiogenic shock. She was weaned off VA-ECMO after 4 days but continued to have severely reduced cardiac function. RHC revealed severe volume overload, pulmonary venous hypertension, low cardiac output, and right heart dysfunction. Echo showed severe LV dysfunction with an EF of 15%. A femoral intra-aortic balloon pump(IABP) was placed on July 7, 2020. An attempt was made to wean her off of IABP on July 10^th,however, it was unsuccessful and she was transitioned to axillary intra-aortic balloon pump. She remained IABP dependent thereafter and on July 15th, given persistent cardiogenic shock, decision was made to pursue advanced heart failure therapies. After multi-disciplinary discussion, the decision to pursue LVAD implantation was made. She underwent a successful LVAD implantation on July 20^th . She failed an extubation trial and underwent tracheostomy on July 23^rd . Post LVAD, she developed atrial fibrillation and was started on digoxin and amiodarone. Her symptoms improved and she was subsequently discharged to rehabilitation in late August on amiodarone, digoxin, metoprolol, prasugrel, warfarin, spironolactone and lisinopril. The detailed timeline is shown in figure 1.

Summary

Hypercoagulability and severe inflammatory stress leading to life-threatening illness is a significant complication of COVID-19 infection. A low threshold for suspecting and treating hypercoagulability and inflammatory induced myocardial ischemia and injury and cardiogenic shock is a reasonable strategy to decrease acute as well as chronic morbidity and mortality.

ECMO for Critically Ill COVID-19 with ARDS: A Case Series

Introduction

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) as bridge to recovery in critically ill COVID-19 continues to be commonly utilized strategy in cases with persistent respiratory failure refractory to traditional ventilation support

Case Report

We report 5 cases of severe acute respiratory syndrome coronavirus-2 infection (SARS-CoV-2) who were treated with ECMO (Table 1). All 5 cases presented with fever, cough and shortness of breath and a positive nasopharyngeal swab for SARS-CoV-2 on admission. Case 1, 2, 3 and 5 patients were hypoxemic with saturation less than 90% on admission and decompensated rapidly, whereas Case 4 decompensated after day 14. Mechanical ventilation failed to provide adequate oxygenation in all 5 cases; case 2,3 and 5 were started on recruitment measures with proning while it was not possible for case 1 owing to morbid obesity. Proning was not possible in the case 4 as patient became severely hypoxemic while patient was undergoing mechanical thrombectomy. The case 1-4 remained on ECMO for 19, 17, 17 and 2 days respectively. All except case 2 had improvement in APACHEII and SOFA score after ECMO initiation. All 5 patients had elevated inflammatory markers of serum ferritin, D-dimer, Lactate dehydrogenase (LDH), C-reactive protein (CRP) which trended down after a few days of ECMO initiation All 5 patients received high dose steroids during their stay in the ICU. Case 4 and 5 passed away after compassionate extubation. Case 1-3 had prolonged hospital course with complication of hospital acquired pneumonia requiring multiple courses of broad-spectrum antibiotics.

Summary

Our observational report of 5 patients reports the use of ECMO in critically ill SARS-CoV-2 with ARDS and difficult to maintain saturation despite mechanical ventilation and proning with recovery for 3 patients. However, given the lack of ECMO centers; this is not a readily available option. Further studies are warranted to investigate the role of ECMO in SARRS-CoV-2 and careful identification of appropriate candidates.

A qualitative study exploring older smokers' attitudes and motivation toward quitting during the COVID-19 pandemic

Older individuals who smoke are at increased risk of having severe outcomes from COVID-19, due to their long-term smoking and underlying health conditions. In this qualitative study, we explored the impact of COVID-19 on attitudes toward smoking and motivation to quit. Participants (N = 30) were enrolled in a larger ongoing randomized controlled smoking cessation trial conducted in the lung cancer screening setting. From March to May 2020, we assessed quantitative and qualitative responses to participants' overall concern about COVID-19, changes in amount smoked, and motivation to reduce/quit smoking. Responses to the quantitative questions indicated that 64.3% of participants were extremely concerned with COVID-19, 20.7% reported reductions in amount smoked, and 37.9% reported increased motivation to quit. The qualitative responses, which were transcribed and coded using Consensual Qualitative Research guidelines, expanded upon these findings by providing the content of participants' concerns, which included perceived risk of contracting COVID-19, the added stressors caused by COVID-19, and a variable impact on the amount smoked and motivation to quit. Although half of participants expressed extreme concern regarding COVID-19, fewer indicated increased motivation or reduced smoking. Qualitative themes suggested that the initial two months of the pandemic prompted some smokers to reduce or quit, but it exacerbated smoking triggers for others. Understanding how the pandemic continues to affect this vulnerable group will aid in adapting methods to support their efforts to stop smoking and remain abstinent.

Disparities in colorectal cancer screening among breast and prostate cancer survivors

Background

Colorectal cancer (CRC) screening is recommended as an integral part of cancer survivorship care. We compared the rates of CRC screening among breast and prostate cancer survivors by primary cancer type, patient, and geographic characteristics in a community‐based health‐care system with a mix of large and small metro urban areas.

Materials and Methods

Data for this retrospective study were abstracted from medical records of a multi‐specialty practice serving about 250,000 individuals in southern Maryland. Breast (N = 1056) and prostate (N = 891) cancer patients diagnosed prior to 2015 were followed up till June 2018. Screening colonoscopy within the last 10 years was considered to be guideline concordant. Multivariate logistic regression was used to determine the prevalence odds ratios of being concordant on CRC screening by age, gender, race, metro area type, obesity, diabetes, and hypertension.

Results

Overall 51% of survivors had undergone a screening colonoscopy. However, there was a difference in CRC screening rate between prostate (54%) and breast (44%) cancer survivors. Older age (≥65 years), being a breast cancer survivor compared to prostate cancer, and living in a large compared to small metropolitan area were associated with a lower probability of receiving CRC screening. Having hypertension was associated with higher likelihood of being current on colonoscopy screening guidelines among survivors; but diabetes and obesity were not associated with CRC screening.

Conclusions

Low levels of CRC screening utilization were found among breast and prostate cancer survivors in a single center in Southern Maryland. Gender, comorbidities, and residential factors were associated with receipt of CRC screening.

Investigation of the composition of arterial plaques based on arterial waveforms and material properties

Stroke is mainly caused by a narrowing of the carotid artery from a build-up of plaque. The risk of plaque rupture and subsequent stroke is dependent on plaque composition. Advances in imaging modalities offer a non-invasive means to assess the health of blood vessels and detect damage. However, the current diagnosis fails to identify patients with soft lipid plaque that are more susceptible to fissure, resulting in stroke. The aim of this study was to use waveform analysis to identify plaque composition and the risk of rupture. We have investigated pressure and flow by combining an artificial blood flow circuit with tubing containing different materials, to simulate plaques in a blood vessel. We used fat and bone to model lipid and calcification respectively to determine if the composition of plaques can be identified by arterial waveforms. We demonstrate that the arterial plaque models with different percentages of calcification and fat, results in significantly different arterial waveforms. These findings imply that arterial waveform analysis has the potential for further development to identify the vulnerable plaques prone to rupture. These findings could have implications for improved patient prognosis by speed of detection and a more appropriate treatment strategy.

Effects of sustained proNGF blockade on attentional capacities in aged rats with compromised cholinergic system

Disruption in nerve growth factor (NGF) signaling via tropomyosin-related kinase A (trkA) receptors compromises the integrity of the basal forebrain (BF) cholinergic system, yielding cognitive, specifically attentional, impairments in Alzheimer's disease (AD). Although normal aging is considered a risk factor for AD, the mechanisms underlying the selective vulnerability of the aging cholinergic system to trkA disruption is not clear. The levels of proNGF, a proneurotrophin that possesses higher affinity for p75 receptors, increase in aging. The present study was designed to test the hypothesis that cholinergic and attentional dysfunction in aged rats with reduced BF trkA receptors occurs due to the overactivation of endogenous proNGF signaling. We employed a viral vector that produced trkA shRNA to suppress trkA receptors in the corticopetal cholinergic neurons of aged rats. BF trkA suppression impaired animals' performance on signal trials in both the sustained attention task (SAT) and the cognitively taxing distractor version of SAT (dSAT) and these deficits were normalized by chronic intracerebroventricular administration of proNGF antibody. Moreover, depolarization-evoked acetylcholine (ACh) release and the density of cortical cholinergic fibers were partially restored in these animals. However, SAT/dSAT scores reflecting overall performance did not improve following proNGF blockade in trkA knockdown rats due to impaired performance in non-signal trials. Sustained proNGF blockade alone did not alter baseline attentional performance but produced moderate impairments during challenging conditions. Collectively, our findings indicate that barring proNGF-p75 signaling may exert some beneficial effects on attentional capacities specifically when BF trkA signaling is abrogated. However, endogenous proNGF may also possess neurotrophic effects and blockade of this proneurotrophin may not completely ameliorate attentional impairments in AD and potentially hinder performance during periods of high cognitive load in normal aging.

Preparation and characterization of monolithic HgCdTe/CdTe tandem cells

A prototype monolithic HgCdTe/CdTe superstrate tandem cell has been fabricated by RF sputtering, comprising a CdTe/CdS top cell, a ZnTe:N/ZnO:Al interconnect junction and a HgCdTe/CdS bottom cell. The Hg1−xCdxTe film as the bottom absorption layer was deposited by RF sputtering with 70% or 85% Cd content in the Hg1−xCdxTe magnetron target. Hg1−xCdxTe films with band gap from 0.98 eV to 1.45 eV were obtained by controlling the deposition temperature. CdCl2 thermal treatments were used to improve the Hg1−xCdxTe film electrical properties. A nitrogen-doped ZnTe film combined with an aluminium (Al) doped ZnO film formed a good interconnect junction. Results of Voc = 0.99 V and Jsc = 2.1 mA/cm2 were obtained in the best such tandem cell at one sun (AM1.5).

Reduced expression and capacity of the striatal high-affinity choline transporter in hyperdopaminergic mice

Behavioral and neuronal abnormalities observed in mice exhibiting a reduced expression of the dopamine transporter model important aspects of schizophrenia, addiction, and attentional disorders. As the consequences of a chronic hyperdopaminergic tone for striatal output regulation have remained poorly understood, the present experiments were designed to determine the status of striatal interneuronal cholinergic neurotransmission in dopamine transporter knockdown animals. The high-affinity choline transporter represents the rate-limiting step of acetylcholine synthesis and release. Compared with wild type mice, striatal high-affinity choline transporter expression in dopamine transporter knockdown mice was significantly decreased. As in vivo basal striatal acetylcholine release did not differ between the strains, reduced high-affinity choline transporter expression in dopamine transporter knockdown mice was not due to reduced basal cholinergic activity. Furthermore, the proportion of high-affinity choline transporters expressed in plasma membrane-enriched versus vesicular membrane-enriched fractions did not differ from wild type animals, suggesting that changes in intracellular high-affinity choline transporter trafficking were not associated with lower overall levels of striatal high-affinity choline transporters. Synaptosomal choline uptake assays indicated a reduced capacity of striatal high-affinity choline transporters in dopamine transporter knockdown mice, and thus the functional significance of the reduced level of high-affinity choline transporter expression. Likewise, in vivo measures of the capacity of striatal high-affinity choline transporters to clear increases in extracellular choline concentrations, using choline-sensitive microelectrodes, revealed a 37-41% reduction in hemicholinium-sensitive clearance of exogenous choline in dopamine transporter knockdown mice. Furthermore, clearance of potassium-evoked choline signals was reduced in dopamine transporter knockdown mice (1.63+/-0.15 microM/s) compared with wild type animals (2.29+/-0.21 microM/s). Dysregulated striatal cholinergic neurotransmission is hypothesized to disrupt the integration of thalamic and cortical information at spiny projection neurons and thus to contribute to abnormal striatal information processing in dopamine transporter knockdown mice.

Cortical choline transporter function measured in vivo using choline-sensitive microelectrodes: clearance of endogenous and exogenous choline and effects of removal of cholinergic terminals

The capacity of the high-affinity choline transporter (CHT) to import choline into presynaptic terminals is essential for acetylcholine synthesis. Ceramic-based microelectrodes, coated at recording sites with choline oxidase to detect extracellular choline concentration changes, were attached to multibarrel glass micropipettes and implanted into the rat frontoparietal cortex. Pressure ejections of hemicholinium-3 (HC-3), a selective CHT blocker, dose-dependently reduced the uptake rate of exogenous choline as well as that of choline generated in response to terminal depolarization. Following the removal of CHTs, choline signal recordings confirmed that the demonstration of potassium-induced choline signals and HC-3-induced decreases in choline clearance require the presence of cholinergic terminals. The results obtained from lesioned animals also confirmed the selectivity of the effects of HC-3 on choline clearance in intact animals. Residual cortical choline clearance correlated significantly with CHT-immunoreactivity in lesioned and intact animals. Finally, synaptosomal choline uptake assays were conducted under conditions reflecting in vivo basal extracellular choline concentrations. Results from these assays confirmed the capacity of CHTs measured in vivo and indicated that diffusion of substrate away from the electrode did not confound the in vivo findings. Collectively, these results indicate that increases in extracellular choline concentrations, irrespective of source, are rapidly cleared by CHTs.

Comparison of Galantamine and Donepezil for Effects on Nerve Growth Factor, Cholinergic Markers, and Memory Performance in Aged Rats

This study was designed to determine 1) whether repeated exposures to the acetylcholinesterase inhibitors (AChEIs) galantamine (GAL) or donepezil (DON) resulted in positive effects on nerve growth factor (NGF) and its receptors, cholinergic proteins, and cognitive function in the aged rat, and 2) whether GAL had any advantages over DON given its allosteric potentiating ligand (APL) activity at nicotinic acetylcholine receptors. Behavioral tests (i.e., water maze and light/dark box) were conducted in aged Fisher 344 rats during 15 days of repeated (subcutaneous) exposure to either GAL (3.0 or 6.0 mg/kg/day) or DON (0.375 or 0.75 mg/kg/day). Forty-eight hours after the last drug injection, cholinergic receptors were measured by [(125)I]-(+/-)-exo-2-(2-iodo-5-pyridyl)-7-azabicyclo[2.2.1]heptane ([(125)I]IPH; epibatidine analog), (125)I-alpha-bungarotoxin ((125)I-BTX), [(3)H]pirenzepine ([(3)H]PRZ), and [(3)H]-5,11-dihydro-11-[((2-(2-((dipropylamino)methyl)-1-piperidinyl)ethyl)amino)carbonyl]-6H-pyrido(2,3-b)(1,4)-benzodiazepin-6-one methanesulfonate ([(3)H]AFDX-384, or [(3)H]AFX) autoradiography. Immunochemical methods were used to measure NGF, high (TrkA and phospho-TrkA)- and low (p75 neurotrophin receptor)-affinity NGF receptors, choline acetyltransferase (ChAT), and the vesicular acetylcholine transporter (VAChT) in memory-related brain regions. Depending on dose, both GAL and DON enhanced spatial learning (without affecting anxiety levels) and increased [(125)I]IPH, [(3)H]PRZ, and [(3)H]AFX (but decreased (125)I-BTX) binding in some cortical and hippocampal brain regions. Neither AChEI was associated with marked changes in NGF, NGF receptors, or VAChT, although DON did moderately increase ChAT in the basal forebrain and hippocampus. The results suggest that repeated exposures to either GAL or DON results in positive (and sustained) behavioral and cholinergic effects in the aged mammalian brain but that the APL activity of GAL may not afford any advantage over acetylcholinesterase inhibition alone.

Differential effects of chronic haloperidol and olanzapine exposure on brain cholinergic markers and spatial learning in rats

RATIONALE

In psychiatric patients, haloperidol (HAL) induces a number of adverse extrapyramidal and cognitive symptoms, which appear to be less problematic with olanzapine (OLZ). In animals, HAL may initiate a number of harmful effects on central nervous system neurons, including damage to cholinergic pathways - an effect that could be especially deleterious to those experiencing memory dysfunction. The identification of the neurobiological substrates of such effects in animal models may help to improve the algorithms used for proper drug selection especially for long-term neuroleptic use.

OBJECTIVES

The aim of this study was to compare the effects of chronic (45-day and 90-day), continuous oral exposure to HAL with OLZ for effects on cognitive performance and cholinergic markers in rats.

METHODS

After chronic neuroleptic exposure (and a 4-day washout) spatial memory performance was measured in a water maze task, and choline acetyltransferase (ChAT) immunoreactivity was assessed with immunofluorescence staining.

RESULTS

In water maze experiments, HAL and OLZ (relative to vehicle) administered for 90 days (but not 45 days) significantly impaired learning performance (i.e., higher mean latencies across several trials to reach a hidden platform). HAL administered for 90 days was associated with impairment across a greater number of trials than OLZ and it also impaired probe trial performance, as indicated by a reduced number of crossings over the previous platform area (when compared with OLZ or vehicle). Both 45 days and 90 days of HAL treatment reduced ChAT staining in the cortex and hippocampus when compared with OLZ or vehicle.

CONCLUSIONS

The results in the rat suggest that OLZ (relative to HAL) may be more desirable as an antipsychotic for patients suffering from memory dysfunction especially for those in which cholinergic deficits may already be present.

Persistent mullerian duct syndrome with teratoma in an ectopic testis: imaging features

The persistent mullerian duct syndrome represents a rare form of male pseudohermaphroditism, secondary to mullerian inhibiting factor (MIF) deficiency. We describe imaging findings in a 30-year-old male (46 XY karyotype) with bilateral cryptorchidism and mullerian duct anomalies (presence of uterus and fallopian tubes). Grade-III teratoma with yolk sac tumour was detected in one of the undescended testis, lying in the pelvic cavity. The other testis was in the inguinal canal. The rest of the wolffian duct structures (e.g. prostate, seminal vesicles) were nearly normal. Very few reports of imaging findings of this entity have been published thus far, probably because of the rarity of entity, incidental detection of most of the cases at surgery and relatively asymptomatic clinical presentation.

Possible role of nitric oxide and mast cells in endotoxin-induced cardioprotection

The present study is designed to investigate the role of nitric oxide (NO) and cardiac mast cells in the cardioprotective effect of endotoxin in isolated rat heart subjected to 30 min of global ischaemia and 30 min of reperfusion. Endotoxin (2.5 mg kg(-1); i.p.) was administered 8 h before subjecting the heart to global ischaemia. Endotoxin pretreatment markedly reduced the release of lactate dehydrogenase (LDH) and creatine kinase (CK), markers of cardiac injury, in coronary effluent and the percentage incidence of ventricular premature beats (VPBs) and ventricular tachycardia/fibrillation (VT/VF) during the reperfusion phase. Endotoxin pretreatment significantly increased the release of nitrite prior to and after global ischaemia. On the other hand, endotoxin pretreatment decreased the release of mast cell peroxidase (MPO) during the reperfusion phase. The cardioprotective and antiarrhythmic effect of endotoxin pretreatment was abolished by dexamethasone (3 mg kg(-1); i.p.) or l -canavanine (20 mg kg(-1); i.p.) given 1 h before the administration of endotoxin. It is proposed that the cardioprotective and antiarrhythmic effect of the endotoxin may be ascribed to the induction of nitric oxide synthase (NOS) and subsequent increase in the release of NO. NO may stabilize cardiac mast cells and consequently decrease the release of cytotoxic mediators from these cells. Prevention of degranulation of cardiac mast cells may be responsible for the cardioprotective and antiarrhythmic effects of the endotoxin.

Possible role of cardiac mast cell degranulation and preservation of nitric oxide release in isolated rat heart subjected to ischaemic preconditioning

Our study is designed to correlate nitrite concentration, an index of nitric oxide (NO) release with mast cell peroxidase (MPO), a marker of cardiac mast cell degranulation and cardioprotective effect of ischaemic preconditioning in isolated perfused rat heart subjected to 30 min of global ischaemia and 30 min of reperfusion. Ischaemic preconditioning, comprised of four episodes of 5 min global ischaemia and 5 min of reperfusion, markedly reduced the release of lactate dehydrogenase (LDH) and creatine kinase (CK) in coronary effluent and incidence of ventricular premature beats (VPBs) and ventricular tachycardia and fibrillation (VT/VF) during reperfusion phase. Ischaemia-reperfusion induced release of MPO was markedly reduced in ischaemic preconditioned hearts. Increased release of nitrite was noted during reperfusion phase after sustained ischaemia in preconditioned hearts as compared to control hearts. No alterations in the release of nitrite was observed immediately after ischaemic preconditioning. However, ischaemic preconditioning markedly increased the release of MPO prior to global ischaemia. It is proposed that cardioprotective and antiarrhythmic effect of ischaemic preconditioning may be ascribed to degranulation of cardiac mast cells. Depletion of cytotoxic mediators during ischaemic preconditioning and consequent decreased release of these mediators during sustained ischaemia-reperfusion may be associated with preservation of structures in isolated rat heart responsible for NO release.

Possible role of adrenergic component and cardiac mast cell degranulation in preconditioning-induced cardioprotection

The present study was designed to investigate the role of adrenergic component and cardiac mast cell degranulation in the cardioprotective effect of ischaemic preconditioning. Isolated rat hearts were subjected to 30 min of global ischaemia followed by 30 min of reperfusion. Ischaemic/norepinephrine (100 microm) preconditioning markedly reduced ischaemia-reperfusion-induced release of lactate dehydrogenase (LDH) and creatine kinase (CK) in coronary effluent and the incidence of ventricular premature beats (VPBs) and ventricular tachycardia/fibrillation (VT/VF) during the reperfusion phase. Moreover, ischaemic/norepinephrine preconditioning significantly reduced ischaemia-reperfusion-induced release of mast cell peroxidase (MPO), a marker of mast cell degranulation. Prazosin (0.1 microm), a alpha(1)adrenoceptor blocker, administered during ischaemic/norepinephrine preconditioning attenuated the cardioprotective and antiarrhythmic effect of ischaemic/norepinephrine preconditioning. MPO release increased immediately after ischaemic/norepinephrine preconditioning and the release was found to be inhibited in hearts subjected to ischaemic/norepinephrine preconditioning in the presence of prazosin. However, prazosin (0.1 microm) treatment per se produced cardioprotective and antiarrhythmic effects and reduced ischaemia-reperfusion-induced MPO release. These findings tentatively suggest that ischaemic preconditioning produced cardioprotective and antiarrhythmic effect by activating alpha(1)adrenoceptors and consequent degranulation of cardiac mast cells. Prazosin administered during ischaemic preconditioning abolished its ameliorative effect.

Possible role of cardiac mast cells in norepinephrine-induced myocardial preconditioning

The present study was designed to investigate the role of cardiac mast cells in the cardioprotective effect of norepinephrine-induced preconditioning. Isolated rat heart was subjected to 30 min of global ischemia followed by 30 min of reperfusion. Both ischemic and norepinephrine (100 microM) preconditioning markedly reduced ischemia-reperfusion-induced release of lactate dehydrogenose (LDH) in the coronary effluent and the incidence of ventricular premature beats (VPBs) and ventricular tachycardia/fibrillation (VT/VF) during the reperfusion phase. Ischemic and norepinephrine preconditioning also significantly reduced ischemia-reperfusion-induced release of mast cell peroxidase (MPO), a marker of mast cell degranulation. However, MPO release increased immediately after ischemic or norepinephrine preconditioning. Histological study with ruthenium red (0.005%) staining confirmed cardiac mast cell degranulation in ischemic and norepinephrine preconditioned isolated rat hearts. These findings tentatively suggest that pharmacological preconditioning with norepinephrine produces a cardioprotective and antiarrhythmic effect similar to ischemic preconditioning through degranulation of resident cardiac mast cells.

Acute acalculous cholecystitis in young patients without predisposing factors

We report the atypical presentation of acute acalculous cholecystitis in four young, otherwise healthy patients. These cases emphasize the fact that the traditional concept of this disease as being associated with trauma, major surgery, or other pathology may no longer be true, and an important number of cases may appear de novo in patients without any predisposing factors.

Cardiac mast cell stabilization and cardioprotective effect of ischemic preconditioning in isolated rat heart

This study was designed to investigate the effect of disodium cromoglycate (DSCG), a mast cell stabilizer, on cardioprotective effect of ischemic preconditioning. Isolated rat heart was subjected to 30 min of global ischemia followed by 30 min of reperfusion. Ischemic preconditioning was provided by four episodes of 5-min global ischemia followed by 5 min of reperfusion before sustained ischemia. Ischemic preconditioning and DSCG (10 and 100 microM) treatment markedly decreased the release of lactate dehydrogenase (LDH) and creatine kinase (CK) in coronary effluent and percentage incidence of ventricular premature beats (VPBs) and ventricular tachycardia/fibrillation (VT/VF) during reperfusion. Ischemic preconditioning and DSCG treatment also significantly reduced ischemia/reperfusion-induced mast cell peroxidase (MPO) release, a marker of mast cell degranulation. A significant increase in MPO release was observed immediately after ischemic preconditioning, and the release was found to be inhibited in hearts perfused with DSCG (10 and 100 microM) during ischemic preconditioning. DSCG administered during ischemic preconditioning (DSCG in ischemic preconditioning) attenuated the cardioprotective and antiarrhythmic effects of ischemic preconditioning. DSCG in ischemic preconditioning produced no marked effect on ischemia/reperfusion-induced MPO release. These findings tentatively suggest that DSCG administration during ischemic preconditioning abolishes its cardioprotective effect, perhaps by stabilizing resident cardiac mast cells.

Differential effects of light and heat on the Drosophila circadian clock proteins PER and TIM

Circadian (approximately 24-h) rhythms are governed by endogenous biochemical oscillators (clocks) that in a wide variety of organisms can be phase shifted (i.e., delayed or advanced) by brief exposure to light and changes in temperature. However, how changes in temperature reset circadian timekeeping mechanisms is not known. To begin to address this issue, we measured the effects of short-duration heat pulses on the protein and mRNA products from the Drosophila circadian clock genes period (per) and timeless (tim). Heat pulses at all times in a daily cycle elicited dramatic and rapid decreases in the levels of PER and TIM proteins. PER is sensitive to heat but not light, indicating that individual clock components can markedly differ in sensitivity to environmental stimuli. A similar resetting mechanism involving delays in the per-tim transcriptional-translational feedback loop likely underlies the observation that when heat and light signals are administered in the early night, they both evoke phase delays in behavioral rhythms. However, whereas previous studies showed that the light-induced degradation of TIM in the late night is accompanied by stable phase advances in the temporal regulation of the PER and TIM biochemical rhythms, the heat-induced degradation of PER and TIM at these times in a daily cycle results in little, if any, long-term perturbation in the cycles of these clock proteins. Rather, the initial heat-induced degradation of PER and TIM in the late night is followed by a transient and rapid increase in the speed of the PER-TIM temporal program. The net effect of these heat-induced changes results in an oscillatory mechanism with a steady-state phase similar to that of the unperturbed control situation. These findings can account for the lack of apparent steady-state shifts in Drosophila behavioral rhythms by heat pulses applied in the late night and strongly suggest that stimulus-induced changes in the speed of circadian clocks can contribute to phase-shifting responses.

Pharmacological basis of drug therapy of Alzheimer's disease

Alzheimer's disease is a progressive neurodegenerative disorder primarily manifesting as a loss of memory. Senile plaques and neurofibrillary tangles are the major histopathological alteration in the brain of Alzheimer's disease patients. A considerable deficiency of cholinergic neurons is a consistent finding in Alzheimer's disease. Therefore, many therapeutic strategies to augment cerebral concentration of acetylcholine such as cholinergic precursors, cholinergic receptor agonists, cholinesterase inhibitors and acetylcholine release modulators have been evaluated in Alzheimer's disease. Although cholinesterase inhibitors such as tacrine and galanthamine offer modest clinical benefits, other cholinergic agents have proved to be of limited therapeutic value. Efforts to enhance monoaminergic neurotransmission have also been largely disappointing. Therefore, emphasis is not being put on the use of combination of two class of drugs. Moreover, use of therapeutic agents based on the putative pathogenic etiology of the disease such as excitotoxicity, amyloidosis, aluminium accumulation, inflammatory mechanisms and free radical production is being evaluated. Desferrioxamine, non-steroidal anti-inflammatory drugs, prednisone, dapsone, vitamin E and idebenone are some such agents that are currently under investigation for the preventive or palliative effect in Alzheimer's disease. Neurotrophic factors such as nerve growth factor, brain derived neurotrophic factor and epidermal growth factor have shown promising results in animal studies. However, novel methods for delivering these molecules into the brain required to be developed before launching their clinical trials in man.

Effect of amiloride A Na+/H+ exchange inhibitor on cardioprotective effect of ischaemic preconditioning: possible involvement of resident cardiac mast cells

The present study was designed to investigate the effect of amiloride, a Na+/H+ exchange inhibitor on cardioprotective effect of ischaemic preconditioning in isolated rat heart. Four episodes of ischaemic preconditioning and amiloride (174 microM) treatment markedly decreased the release of lactate dehydrogenase (LDH) and creatine kinase (CK) in coronary effluent and infarct size in hearts subjected to 30 min of global ischaemia followed by 120 min of reperfusion. Amiloride (174 microM) administered during ischaemic preconditioning (Amiloride in Ischaemic Preconditioning), produced no marked effect on LDH and CK release and infarct size. Ischaemic preconditioning and amiloride treatment significantly reduced ischaemia/reperfusion induced release of mast cell peroxidase (MPO). Four episodes of pH (20 mm of ammonium chloride) preconditioning also produced cardioprotection and decreased ischaemia/reperfusion induced release of MPO. It is interesting to note that a significant increase in release of MPO was observed immediately after ischaemic preconditioning and the release was inhibited by amiloride. Moreover, similar increase in MPO release was noted immediately after pH preconditioning. These findings tentatively suggest that ischaemic preconditioning and pH preconditioning produced cardioprotective effect by activating Na+/H+ exchange and consequent degranulation of resident cardiac mast cells. Amiloride administered during ischaemic preconditioning attenuated the cardioprotective effect of ischaemic preconditioning.

Proliferation markers and cell cycle associated expression of prosomes in breast cancers of Parsis and non-Parsis

The present study has focused attention essentially on the Parsis, an ethnic group with high breast cancer incidence. We have investigated the potential use of prosomes, compared to Ki-67 and PCNA, as an additional cell proliferation marker. We also addressed the question whether or not breast tumors of Parsis differed in their DNA index and in the proportion of the S-phase fraction, compared to that of non-Parsi and European patients. We observed that the benign tumors of Parsis and non-Parsis were hyperdiploids, whereas in case of malignant tumors the Parsis showed essentially diploid characteristics while hyperdiploidy prevailed in the non-Parsis. Tetraploidy was seen as a common feature in the non-Parsis, whereas aneuploidy seemed to be the more common type in the Parsis. The cell cycle analysis also revealed some interesting differences between the cell proliferation compartments of these two populations. A high number of cells in G2+M and S-phases was seen for non-Parsi malignant tumors while only the S-phase had a large cell count in the Parsis malignant tumors. The malignant tumors of Parsis and non-Parsis showed, as would be expected, a high expression of Ki-67 in the proliferation compartment. Surprisingly high Ki-67 expression was also a feature seen in the benign tumors of Parsis only and not any other group. We observed that expression of Ki-67, a proliferation marker directly related to the degree of malignancy, paralleled that of prosomal protein expression. In addition the prosomal monoclonal antibodies appeared to be more sensitive than Ki-67 in detecting a larger quantum of cells in the proliferation compartment.

Resident cardiac mast cells and the cardioprotective effect of ischemic preconditioning in isolated rat heart

Our study was designed to investigate the role of resident cardiac mast cells in the cardioprotective effect of ischemic preconditioning. Ischemic/compound 48/80 preconditioning and treatment with compound 48/80, a mast cell degranulator (1 microg/ml), produced cardioprotective and antiarrhythmic effects in isolated perfused rat heart subjected to 30-min global ischemia followed by 30-min reperfusion. Four episodes of ischemic/compound 48/80 preconditioning and compound 48/80 treatment markedly reduced the release of lactate dehydrogenase (LDH) and creatine kinase (CK) in coronary perfusate and the incidence of ventricular premature beats (VPBs) and ventricular tachycardia or fibrillation (VT/VF) during the reperfusion phase. The release of mast cell peroxidase (MPO), a marker of mast cell degranulation in coronary perfusate, increased immediately after ischemic and compound 48/80 preconditioning. The cardioprotective and antiarrhythmic effect of ischemic/compound 48/80 preconditioning was lost within 60 min. It is proposed that the cardioprotective effect of ischemic preconditioning, which lasts for 60 min in isolated rat heart, may be ascribed to degranulation of resident cardiac mast cells.

Resetting the Drosophila clock by photic regulation of PER and a PER-TIM complex

Circadian clocks can be reset by light stimulation. To investigate the mechanism of this phase shifting, the effects of light pulses on the protein and messenger RNA products of the Drosophila clock gene period (per) were measured. Photic stimuli perturbed the timing of the PER protein and messenger RNA cycles in a manner consistent with the direction and magnitude of the phase shift. In addition, the recently identified clock protein TIM (for timeless) interacted with PER in vivo, and this association was rapidly decreased by light. This disruption of the PER-TIM complex in the cytoplasm was accompanied by a delay in PER phosphorylation and nuclear entry and disruption in the nucleus by an advance in PER phosphorylation and disappearance. These results suggest a mechanism for how a unidirectional environmental signal elicits a bidirectional clock response.

Perforated solitary jejunal diverticulum

We report a case of perforated solitary jejunal diverticulum in an 80-year-old woman. Jejunal diverticulosis occurs in 0.07% to 2.0% of the population. Jejunal diverticulitis with perforation is rare and is associated with high mortality. Treatment is surgical resection of the involved segment. Several theories to explain the pathogenesis of jejunal diverticula may relate to manometric or histologic abnormalities of the small bowel.

Delayed splenic rupture in a drug addict

We present the case of a drug addict who was admitted with abdominal pain but gave no history of trauma. He subsequently left the hospital against medical advice, only to be readmitted a few days later with persistent abdominal pain. He was found to have splenic rupture. This case emphasizes the importance of ruling out intra-abdominal trauma in any drug addict presenting with acute abdomen.

Safety of copper T as contraceptive after caesarean section

Copper T was inserted in 45 cases following caesarean section. Motivation was easier, acceptance was higher and follow-up was good in this group of patients. With proper selection and careful follow-up complications could be reduced to the minimum.

An association between schistosomes and contrapsin, a mouse serine protease inhibitor (serpin)

An antigen in homogenates of adult Schistosoma mansoni worms grown in mice, and immunoprecipitated by polyspecific rabbit antiserum, has been identified as contrapsin, a mouse serine protease inhibitor (serpin). In the serum of some mice infected with S. mansoni contrapsin was found with altered immunoelectrophoretic characteristics when compared with contrapsin from uninfected mice.