Curricular Reform in Serious Illness Communication and Palliative Care: Using Medical Students' Voices to Guide Change

PURPOSE

To gather and leverage the voices of students to drive creation of required, integrated palliative care curricula within undergraduate medical education in Massachusetts, which is lacking in a majority of U.S. medical schools.

METHOD

The study was conducted by the Massachusetts Medical Schools' Collaborative, a working group committed to ensuring all medical students in Massachusetts receive foundational training in serious illness communication (SIC) and palliative care. Eight focus groups (2 per participating medical school) were conducted during January-May 2021 and included a total of 50 students from Boston University Chobanian & Avedisian School of Medicine, Harvard Medical School, Tufts University School of Medicine, and the UMass Chan Medical School. Data collected from focus groups were discussed and coded. Themes were identified using the immersion/crystallization qualitative data analysis approach.

RESULTS

Six key themes emerged. Students viewed SIC as essential to high-quality medical practice regardless of specialty, and believed training in SIC skills and palliative care should be required in medical school curricula. Students preferred to learn and practice these skills using frameworks, particularly in real-world situations. Students recognized the expertise of palliative care specialists and described them as a scarce, often misunderstood resource in health care. Students reported it was mostly "luck" if they were included in family meetings and observed good role models. Finally, students desired practice in debriefing after difficult and emotional situations.

CONCLUSIONS

This study confirms long-standing themes on students' experiences with SIC and palliative care topics, including feeling inadequately prepared to care for seriously ill patients as future physicians. Our study collected students' perspectives as actionable data to develop recommendations for curricular change. Collaborative faculty also created recommendations based on the focus group data for immediate and ongoing SIC and palliative care curricular change in Massachusetts, which can apply to medical schools nationwide.

A Call to Action: Using Curriculum Mapping at Four Medical Schools in Massachusetts to Advance Serious Illness Communication Training in Undergraduate Medical Education

Background: Practicing physicians require serious illness communication (SIC) skills to ensure high-quality, humanistic care for patients and families as they face life-changing medical decisions. However, a majority of U.S. medical schools do not require formal training in SIC and fail to provide students deliberate practice before graduation. The Massachusetts Medical Schools' Collaborative was created to ensure that students receive foundational SIC training in undergraduate medical education. This Collaborative developed a curriculum-mapping tool to assess SIC at four medical schools. Objective: We aimed to understand existing educational activities across four medical schools and identify opportunities to build longitudinal, developmentally based curricular threads in SIC. Design: From July 2019 to April 2021, faculty, staff, and medical students assessed current educational activities related to five core competencies in SIC, adapted for students from national competencies for palliative medicine fellows, using a curriculum mapping tool. Measurements: The group selected 23 keywords and collected metrics to describe the timing, instruction and assessment for each school's educational activities. Results: On average, there were only 40 hours of required curricula in SIC over four years. Over 80% of relevant SIC hours occurred as elective experiences, mostly during the postclerkship phase, with limited capacity in these elective experiences. Only one school had SIC educational activities during the clerkship phase when students are developing clinical competencies. Assessment methods focused on student participation, and no school-assessed clinical performance in the clerkship or postclerkship phase. Conclusions: Medical schools are failing to consistently train and ensure basic competency in effective, compassionate SIC. Curriculum mapping allows schools to evaluate their current state on a particular topic such as SIC, ensure proper assessment, and evaluate curricular changes over time. Through the deliberate inclusion of SIC competencies in longitudinal curriculum design, we can fill this training gap and create best practices in undergraduate medical education.

Online Forums as a Tool for Broader Inclusion of Voices on Health Care Communication Experiences and Serious Illness Care: Mixed Methods Study

BACKGROUND

Existing health care research, including serious illness research, often underrepresents individuals from historically marginalized communities. Capturing the nuanced perspectives of individuals around their health care communication experiences is difficult. New research strategies are needed that increase engagement of individuals from diverse backgrounds.

OBJECTIVE

The aim of this study was to develop a mixed methods approach with qualitative online forums to better understand health communication experiences of individuals, including people from groups historically marginalized such as Black and Latino individuals; older adults; and people with low income, disability, or serious illness.

METHODS

We used a multiphase mixed methods, community-informed research approach to design study instruments and engage participants. We engaged a diverse group of collaborators with lived experience of navigating the health care system who provided feedback on instruments, added concepts for testing, and offered guidance on creating a safe experience for participants (phase 1). We conducted a national quantitative survey between April and May 2021 across intrapersonal, interpersonal, and systems-level domains, with particular focus on interpersonal communication between patients and clinicians (phase 2). We conducted two asynchronous, qualitative online forums, a technique used in market research, between June and August 2021, which allowed us to contextualize the learnings and test concepts and messages (phase 3). Using online forums allowed us to probe more deeply into results and hypotheses from the survey to better understand the "whys" and "whats" that surfaced and to test public messages to encourage action around health.

RESULTS

We engaged 46 community partners, including patients and clinicians from a Federally Qualified Health Center, to inform study instrument design. In the quantitative survey, 1854 adults responded, including 50.5% women, 25.2% individuals over 65 years old, and 51.9% individuals with low income. Nearly two-thirds identified as non-Hispanic white (65.7%), 10.4% identified as non-Hispanic Black, and 15.5% identified as Hispanic/Latino. An additional 580 individuals participated in online forums, including 60.7% women, 17.4% individuals over 65 years old, and 49.0% individuals with low income. Among the participants, 70.3% identified as non-Hispanic white, 16.0% as non-Hispanic Black, and 9.5% as Hispanic/Latino. We received rich, diverse input from our online forum participants, and they highlighted satisfaction and increased knowledge with engagement in the forums.

CONCLUSIONS

We achieved modest overrepresentation of people who were over 65 years old, identified as non-Hispanic Black, and had low income in our online forums. The size of the online forums (N=580) reflected the voices of 93 Black and 55 Hispanic/Latino participants. Individuals who identify as Hispanic/Latino remained underrepresented, likely because the online forums were offered only in English. Overall, our findings demonstrate the feasibility of using the online forum qualitative approach in a mixed methods study to contextualize, clarify, and expound on quantitative findings when designing public health and clinical communications interventions.

Impairment and Disability Identity and Perceptions of Trust, Respect, and Fairness

Importance

Most studies use impaired functioning alone to specify populations with disabilities. However, some people with functional impairments do not identify as disabled. With functional status-based definitions, studies have shown disparate care quality for people with disabilities.

Objective

To examine whether impairment and disability identity have different associations with perceived health care experiences and explore factors associated with disability identification.

Design, Setting, and Participants

This cross-sectional study used a nationally representative survey of US adults conducted from April 20 through May 31, 2021, and analyzed between June 1 and August 31, 2022. Survey participants were 1822 English- or Spanish-speaking adults responding either online or via telephone.

Exposures

Using 8 survey questions, participants were grouped according to presence of impairment and disability identity.

Main Outcomes and Measures

Likert scale measures of trust, respect, and fairness (henceforth, procedural justice measures) were dichotomized. Sociodemographic characteristics and rates of procedural justice responses were compared across groups. Multivariable logistic regressions adjusting for baseline characteristics were performed to (1) estimate associations of impairment and disability identity with perceptions of procedural justice and (2) explore factors associated with disability identification. Analyses applied survey weights.

Results

Of 6126 individuals invited to participate, 1854 (30.3%) completed the survey. Thirty-two were excluded due to unreportable gender, for a final analytic sample of 1822 participants. Participants with impairments (n = 816; mean [SD] age, 48.1 [17.0] years; 51.2% women, 48.8% men) had worse perceptions on 7 of 10 procedural justice measures (crude) compared with those without impairments (n = 1006; mean [SD] age, 49.6 [18.1] years, 55.1% female, 44.9% male). Among respondents with impairments, those who did (n = 340) vs did not (n = 476) identify as disabled gave better ratings for clinician communication efforts (a lot of effort, 38.8% vs 31.0%) and having health goals understood (understood very or fairly well, 77.2% vs 70.1%) but gave worse ratings for respect (almost never felt inferior or talked down to, 66.1% vs 59.1%). Disability identification was associated with more reports of unfair treatment (31.0% vs 22.4%; adjusted odds ratio, 1.65; 95% CI, 1.12-2.42) and of being unafraid to ask questions or disagree (50.5% vs 40.1%; adjusted odds ratio, 1.51; 95% CI, 1.04-20.19). Income and employment were associated with disability identification.

Conclusions and Relevance

In this cross-sectional survey study of US adults, health care perceptions differed between groups defined by impairment status and disability identity. These findings suggest that, alongside functional measures, health systems should capture disability identity to better address disparities for people with impairments.

Understanding primary palliative nursing education in undergraduate nursing programs

BACKGROUND

Nurses are the largest segment of health care professionals and often the first one to interact with individuals about their health and illness. Ensuring nurses have the education to care for individuals with serious illness is essential to quality health care. The new AACN Essentials: Competencies for Professional Nursing Education delineates hospice/palliative/supportive care as one of four spheres of nursing care. Surveying undergraduate schools/colleges of nursing in Massachusetts about content pertaining to care of individuals with serious illness provides the foundation for a state strategy to ensure quality primary palliative education for undergraduate nursing students.

METHODS

A Massachusetts statewide college/school of nursing survey approach to assessing primary palliative nursing education within undergraduate baccalaureate nursing curricula was performed from June 2020 to December 2020. Because the project was a collaboration with the Deans of the college/school of nursing, the survey identified the programs.

RESULTS

Survey results revealed that only a small number of Massachusetts nursing programs are preparing nurses with specific and formal primary palliative nursing education. However, programs are open to support and resources.

CONCLUSION

The survey provided information to inform a successful strategy to support primary palliative nursing education within Massachusetts undergraduate baccalaureate nursing curricula. A survey approach can serve as a model for other states.

Paving the way for universal medical student training in serious illness communication: the Massachusetts Medical Schools' Collaborative

BACKGROUND

Patients with serious illness look to their clinicians for discussion and guidance on high-stakes treatment decisions, which are complex, emotional and value-laden. However, required training in serious illness communication is rare in U.S. medical schools, with efforts at curricular reform stymied by competing institutional demands, lack of resources and accreditation requirements. We describe an approach to building and scaling medical student training in serious illness communication through the creation of a statewide collaborative of medical schools.

METHODS

The Massachusetts Medical Schools' Collaborative is a first-of-its-kind group that promotes longitudinal, developmentally-based curricula in serious illness communication for all students. Convened externally by the Massachusetts Coalition for Serious Illness Care, the collaborative includes faculty, staff, and students from four medical schools.

RESULTS

The collaborative started with listening to member's perspectives and collectively developed core competencies in serious illness communication for implementation at each school. We share early lessons on the opportunities, challenges and sustainability of our statewide collective action to influence curricular reform, which can be replicated in other topic areas.

CONCLUSIONS

Our next steps include curriculum mapping, student focus groups and faculty development to guide successful and enduring implementation of the competencies to impact undergraduate medical education in Massachusetts and beyond.

A Sequential Multiple Assignment Randomized Trial (SMART) study of medication and CBT sequencing in the treatment of pediatric anxiety disorders

BACKGROUND

Treatment of a child who has an anxiety disorder usually begins with the question of which treatment to start first, medication or psychotherapy. Both have strong empirical support, but few studies have compared their effectiveness head-to-head, and none has investigated what to do if the treatment tried first isn't working well-whether to optimize the treatment already begun or to add the other treatment.

METHODS

This is a single-blind Sequential Multiple Assignment Randomized Trial (SMART) of 24 weeks duration with two levels of randomization, one in each of two 12-week stages. In Stage 1, children will be randomized to fluoxetine or Coping Cat Cognitive Behavioral Therapy (CBT). In Stage 2, remitters will continue maintenance-level therapy with the single-modality treatment received in Stage 1. Non-remitters during the first 12 weeks of treatment will be randomized to either [1] optimization of their Stage 1 treatment, or [2] optimization of Stage 1 treatment and addition of the other intervention. After the 24-week trial, we will follow participants during open, naturalistic treatment to assess the durability of study treatment effects. Patients, 8-17 years of age who are diagnosed with an anxiety disorder, will be recruited and treated within 9 large clinical sites throughout greater Los Angeles. They will be predominantly underserved, ethnic minorities. The primary outcome measure will be the self-report score on the 41-item youth SCARED (Screen for Child Anxiety Related Disorders). An intent-to-treat analysis will compare youth randomized to fluoxetine first versus those randomized to CBT first ("Main Effect 1"). Then, among Stage 1 non-remitters, we will compare non-remitters randomized to optimization of their Stage 1 monotherapy versus non-remitters randomized to combination treatment ("Main Effect 2"). The interaction of these main effects will assess whether one of the 4 treatment sequences (CBT➔CBT; CBT➔med; med➔med; med➔CBT) in non-remitters is significantly better or worse than predicted from main effects alone.

DISCUSSION

Findings from this SMART study will identify treatment sequences that optimize outcomes in ethnically diverse pediatric patients from underserved low- and middle-income households who have anxiety disorders.

TRIAL REGISTRATION

This protocol, version 1.0, was registered in ClinicalTrials.gov on February 17, 2021 with Identifier: NCT04760275 .

State of the art conference on weight management in VA: Policy and research recommendations for advancing behavioral interventions

This article summarizes outcomes of the behavioral interventions work group for the Veterans Health Administration (VHA) State of the Art Conference (SOTA) for Weight Management. Sixteen VHA and non-VHA subject matter experts, representing clinical care delivery, research, and policy arenas, participated. The work group reviewed current evidence of efficacy, effectiveness, and implementation of behavioral interventions for weight management, participated in phone- and online-based consensus processes, generated key questions to address gaps, and attended an in-person conference in March 2016. The work group agreed that there is strong evidence for efficacy and effectiveness of core behavioral intervention components and processes, but insufficient evidence to determine the comparative effectiveness of multiple clinician-delivered weight management modalities, as well as technologies that may or may not supplement clinician-delivered treatments. Effective strategies for implementation of weight management services in VHA were identified. The SOTA work group's foremost policy recommendations are to establish a system-wide culture for weight management and to identify a population-level health metric to measure the impact of weight management interventions that can be tracked and clearly communicated throughout VHA. The work group's top research recommendation is to determine how to deploy and scale the most effective behavioral weight management interventions for Veterans.

Implementation of Lung Cancer Screening in the Veterans Health Administration

IMPORTANCE

The US Preventive Services Task Force recommends annual lung cancer screening (LCS) with low-dose computed tomography for current and former heavy smokers aged 55 to 80 years. There is little published experience regarding implementing this recommendation in clinical practice.

OBJECTIVES

To describe organizational- and patient-level experiences with implementing an LCS program in selected Veterans Health Administration (VHA) hospitals and to estimate the number of VHA patients who may be candidates for LCS.

DESIGN, SETTING, AND PARTICIPANTS

This clinical demonstration project was conducted at 8 academic VHA hospitals among 93 033 primary care patients who were assessed on screening criteria; 2106 patients underwent LCS between July 1, 2013, and June 30, 2015.

INTERVENTIONS

Implementation Guide and support, full-time LCS coordinators, electronic tools, tracking database, patient education materials, and radiologic and nodule follow-up guidelines.

MAIN OUTCOMES AND MEASURES

Description of implementation processes; percentages of patients who agreed to undergo LCS, had positive findings on results of low-dose computed tomographic scans (nodules to be tracked or suspicious findings), were found to have lung cancer, or had incidental findings; and estimated number of VHA patients who met the criteria for LCS.

RESULTS

Of the 4246 patients who met the criteria for LCS, 2452 (57.7%) agreed to undergo screening and 2106 (2028 men and 78 women; mean [SD] age, 64.9 [5.1] years) underwent LCS. Wide variation in processes and patient experiences occurred among the 8 sites. Of the 2106 patients screened, 1257 (59.7%) had nodules; 1184 of these patients (56.2%) required tracking, 42 (2.0%) required further evaluation but the findings were not cancer, and 31 (1.5%) had lung cancer. A variety of incidental findings, such as emphysema, other pulmonary abnormalities, and coronary artery calcification, were noted on the scans of 857 patients (40.7%).

CONCLUSIONS AND RELEVANCE

It is estimated that nearly 900 000 of a population of 6.7 million VHA patients met the criteria for LCS. Implementation of LCS in the VHA will likely lead to large numbers of patients eligible for LCS and will require substantial clinical effort for both patients and staff.

Long-Term Air Pollution Exposure and Blood Pressure in the Sister Study

BACKGROUND

Exposure to air pollution has been consistently associated with cardiovascular morbidity and mortality, but mechanisms remain uncertain. Associations with blood pressure (BP) may help to explain the cardiovascular effects of air pollution.

OBJECTIVE

We examined the cross-sectional relationship between long-term (annual average) residential air pollution exposure and BP in the National Institute of Environmental Health Sciences' Sister Study, a large U.S. cohort study investigating risk factors for breast cancer and other outcomes.

METHODS

This analysis included 43,629 women 35-76 years of age, enrolled 2003-2009, who had a sister with breast cancer. Geographic information systems contributed to satellite-based nitrogen dioxide (NO2) and fine particulate matter (≤ 2.5 μm; PM2.5) predictions at participant residences at study entry. Generalized additive models were used to examine the relationship between pollutants and measured BP at study entry, adjusting for cardiovascular disease risk factors and including thin plate splines for potential spatial confounding.

RESULTS

A 10-μg/m(3) increase in PM2.5 was associated with 1.4-mmHg higher systolic BP (95% CI: 0.6, 2.3; p < 0.001), 1.0-mmHg higher pulse pressure (95% CI: 0.4, 1.7; p = 0.001), 0.8-mmHg higher mean arterial pressure (95% CI: 0.2, 1.4; p = 0.01), and no significant association with diastolic BP. A 10-ppb increase in NO2 was associated with a 0.4-mmHg (95% CI: 0.2, 0.6; p < 0.001) higher pulse pressure.

CONCLUSIONS

Long-term PM2.5 and NO2 exposures were associated with higher blood pressure. On a population scale, such air pollution-related increases in blood pressure could, in part, account for the increases in cardiovascular disease morbidity and mortality seen in prior studies.

Experience of the Veterans Health Administration in Massachusetts after state health care reform

Starting in 2006, Massachusetts enacted a series of health insurance reforms that successfully led to 96.6% of its population being covered by 2011. As the rest of the nation undertakes similar reforms, it is unknown how the Veterans Health Administration (VHA), one of many important Federal health care programs, will be affected. Our state-level study approach assessed the effects of health reform on utilization of VHA services in Massachusetts from 2005 to 2011. Models were adjusted for state-level demographic and economic characteristics, including health insurance rates, unemployment rates, median household income, poverty rates, and percent of population 65 years and older. No statistically significant associative change was observed in Massachusetts relative to other states over this time period. The findings raise important questions about the continuing role of VHA in American health care as health insurance coverage is one of many factors that influence decisions on where to seek health care.

Population-specific recombination sites within the human MHC region

Genetic rearrangement by recombination is one of the major driving forces for genome evolution, and recombination is known to occur in non-random, discreet recombination sites within the genome. Mapping of recombination sites has proved to be difficult, particularly, in the human MHC region that is complicated by both population variation and highly polymorphic HLA genes. To overcome these problems, HLA-typed individuals from three representative populations: Asian, European and African were used to generate phased HLA haplotypes. Extended haplotype homozygosity (EHH) plots constructed from the phased haplotype data revealed discreet EHH drops corresponding to recombination events and these signatures were observed to be different for each population. Surprisingly, the majority of recombination sites detected are unique to each population, rather than being common. Unique recombination sites account for 56.8% (21/37 of total sites) in the Asian cohort, 50.0% (15/30 sites) in Europeans and 63.2% (24/38 sites) in Africans. Validation carried out at a known sperm typing recombination site of 45 kb (HLA-F-telomeric) showed that EHH was an efficient method to narrow the recombination region to 826 bp, and this was further refined to 660 bp by resequencing. This approach significantly enhanced mapping of the genomic architecture within the human MHC, and will be useful in studies to identify disease risk genes.

Identification of a novel HLA-C allele, HLA-C*03:85, in a Singaporean Chinese

HLA-C*03:85 differs from C*03:03:01 by a single nucleotide substitution at position 276, in exon 2.

Identification of a novel mutation in the NTF4 gene that causes primary open-angle glaucoma in a Chinese population

PURPOSE

Neurotrophin-4 protein (NT-4) plays a role in the protection of retinal ganglion cells by activating tyrosine kinase B (TrkB) receptors. A recent study identified mutations within the neurotrophin-4 (NTF4) gene to account for 1.7% of primary open-angle glaucoma (POAG) in Europeans. The aim of this study was to investigate the frequency of NTF4 mutations in Chinese POAG patients.

METHODS

One hundred-seventy-four Chinese subjects with POAG and 91 normal Chinese subjects were recruited. POAG was defined by the presence of glaucomatous optic neuropathy, open angles on gonioscopy, and absence of secondary causes of glaucoma. The single coding exon of NTF4 was PCR amplified and subjected to bidirectional sequencing in all subjects.

RESULTS

The mean age of POAG patients was 66.0+/-13.0 years (range 25-96 years) and that of controls was 67.1+/-4.6 years (range 60-85 years). We identified a novel NTF4 missense mutation substituting leucine by serine at codon 113 (Leu113Ser) caused by a c.338T>C mutation in a single patient with unilateral POAG, who presented with a baseline intraocular pressure of 25 mmHg, a vertical cup-to-disc ratio of 0.9 and an inferior hemifield defect in the affected eye. Structural analysis indicated that the Leu113Ser mutation is likely to alter the NT-4 protein structure near the TrkB binding site and disrupts the formation of the NT-4-TrkB complex required for the activation of TrkB.

CONCLUSIONS

Identification of a single mutation in our study suggests that NTF4 mutations are a rare cause of POAG (0.6%, 95%CI 0.02%-3.16%) in Chinese people.

Permanent impairment of birth and survival of cortical and hippocampal proliferating cells following excessive drinking during alcohol dependence

Experimenter-delivered alcohol decreases adult hippocampal neurogenesis and hippocampal-dependent learning and memory. The present study used clinically relevant rodent models of nondependent limited access alcohol self-administration and excessive drinking during alcohol dependence (alcohol self-administration followed by intermittent exposure to alcohol vapors over several weeks) to compare alcohol-induced effects on cortical gliogenesis and hippocampal neurogenesis. Alcohol dependence, but not nondependent drinking, reduced proliferation and survival in the medial prefrontal cortex (mPFC). Apoptosis was reduced in both alcohol groups within the mPFC, which may reflect an initiation of a reparative environment following alcohol exposure as decreased proliferation was abolished after prolonged dependence. Reduced proliferation, differentiation, and neurogenesis were observed in the hippocampus of both alcohol groups, and prolonged dependence worsened the effects. Increased hippocampal apoptosis and neuronal degeneration following alcohol exposure suggest a loss in neuronal turnover and indicate that the hippocampal neurogenic niche is highly vulnerable to alcohol.

Relative predispositional effects of HLA class II DRB1-DQB1 haplotypes and genotypes on type 1 diabetes: a meta-analysis

The direct involvement of the human leukocyte antigen class II DR-DQ genes in type 1 diabetes (T1D) is well established, and these genes display a complex hierarchy of risk effects at the genotype and haplotype levels. We investigated, using data from 38 studies, whether the DR-DQ haplotypes and genotypes show the same relative predispositional effects across populations and ethnic groups. Significant differences in risk within a population were considered, as well as comparisons across populations using the patient/control (P/C) ratio. Within a population, the ratio of the P/C ratios for two different genotypes or haplotypes is a function only of the absolute penetrance values, allowing ranking of risk effects. Categories of consistent predisposing, intermediate ('neutral'), and protective haplotypes were identified and found to correlate with disease prevalence and the marked ethnic differences in DRB1-DQB1 frequencies. Specific effects were identified, for example for predisposing haplotypes, there was a statistically significant and consistent hierarchy for DR4 DQB1*0302s: DRB1*0405 =*0401 =*0402 > *0404 > *0403, with DRB1*0301 DQB1*0200 (DR3) being significantly less predisposing than DRB1*0402 and more than DRB1*0404. The predisposing DRB1*0401 DQB1*0302 haplotype was relatively increased compared with the protective haplotype DRB1*0401 DQB1*0301 in heterozygotes with DR3 compared with heterozygotes with DRB1*0101 DQB1*0501 (DR1). Our results show that meta-analyses and use of the P/C ratio and rankings thereof can be valuable in determining T1D risk factors at the haplotype and amino acid residue levels.

MicroAlbuminuria Prevalence Study (MAPS) in hypertensive type 2 diabetic patients in Hong Kong

OBJECTIVES

To assess the prevalence of macroalbuminuria and microalbuminuria, and the level of blood pressure control in patients with type 2 diabetes and hypertension in Hong Kong.

DESIGN

Cross-sectional clinic-based epidemiological study.

SETTING

Six medical centres (including two public hospital diabetes centres) in Hong Kong.

PATIENTS

Recruited from the medical centres from April to November 2002, after excluding those with bacteriuria and haematuria.

MAIN OUTCOME MEASURES

Body mass index; blood pressure; levels of blood glucose, macroalbuminuria, and microalbuminuria; treatments for hypertension and diabetes.

RESULTS

The as per-protocol recruited population of 437 hypertensive type 2 diabetic patients had a mean age of 61.7 (standard error, 0.5) years. Overall, the prevalence of diabetic nephropathy in this population was high; 18.3% had macroalbuminuria (95% confidence interval, 16.5-20.2%) and 24.9% had microalbuminuria (95% confidence interval, 22.9-27.0%). Predictive factors were advanced age, male sex, poor blood pressure control, and existing cardiovascular complications. Whilst almost all patients (96.1%) were receiving treatment for hypertension, only 25.6% had systolic/diastolic blood pressures below the 130/85 mm Hg target.

CONCLUSIONS

In Hong Kong, the prevalence of microalbuminuria and macroalbuminuria is high in type 2 diabetic patients with hypertension, particularly in males and those with poorly controlled systolic blood pressure. Tight glycaemic control, antihypertensive therapy, and use of renin-angiotensin system inhibitors/blockers are necessary to retard the progression of nephropathy to advanced renal disease.

Immunogenicity and reactogenicity of a reduced-antigen-content diphtheria-tetanus-acellular pertussis vaccine as a single-dose booster in Singaporean adults

INTRODUCTION

Older children and adults, susceptible to pertussis because of waning immunity, may serve as a reservoir of infection, leading to severe disease among young unvaccinated infants. Booster diphtheria-tetanus-acellular pertussis (dTpa) vaccination in older age groups is rare in Singapore, one reason being the increase in reactogenicity with each successive dose. The aim of this study was to assess the immunogenicity, safety and reactogenicity of a reduced antigen, combined dTpa vaccine as a single booster dose in healthy adults aged 18 years or older.

METHODS

A total of 150 healthy adults, 18 to 60 years of age, received a single dose of GlaxoSmithKline Biologicals' dTpa vaccine with reduced content for diphtheria and pertussis, with measurement of pre- and post-vaccination antibody titres.

RESULTS

Prior to vaccination, 71.6 percent and 92.6 percent of the subjects had anti-diphtheria and anti-tetanus antibody levels greater than or equal to 0.1 IU/mL, respectively. 46.7 percent, 98.5 percent and 44.4 percent of subjects were seropositive for pertussis toxin (PT), filamentous haemagglutinin (FHA) and pertactin (PRN) antibodies, respectively. One month after vaccination, there was an increase in geometric mean titres from pre-vaccination to post-vaccination blood samples for anti-diphtheria (greater than seven-fold), anti-tetanus (greater than five-fold), anti-PT (greater than 11-fold), anti- FHA (greater than 25-fold) and anti-PRN (greater than 31-fold) antibodies. Solicited grade three local symptoms (pain, redness and swelling) were reported in 14.1 percent, 8.1 percent and 10.4 percent of subjects, respectively. No serious adverse events were reported.

CONCLUSION

In summary, the dTpa vaccine is immunogenic, safe and well-tolerated in Singaporean adults.

A11 Tetramer-assisted characterization of Rta-specific CD8+ T-cell responses in healthy virus carriers

HLA Class I-restricted CD8(+) T-cell responses are believed to play an important role in controlling Epstein-Barr virus (EBV) infection, which has been consistently associated with nasopharyngeal carcinoma (NPC). Immediate early transactivator Rta of EBV has been shown to be associated with the reactivation of EBV from latency and drive the lytic cascade of EBV and comprise an important target for EBV-specific cellular cytotoxicity. Furthermore, BRLF1 is specifically expressed in NPC tumor cells. The protein product of BRLF1, Rta, could then be considered as a NPC tumor antigen. Therefore, cellular immunity against Rta represents a very important part of the immunity against NPC, as they should prevent the replication of EBV. In the present study, Rta-specific CD8(+) T-cell responses in healthy virus carriers were characterized by using A1101 tetramer containing the known Rta epitope ATIGTAMYK (134-142). We clearly showed A1101/ATIGTAMYK tetramer-reactive CD8(+) T cells in the circulation of healthy virus carriers, ranging from 2.13 to 9.03%. We then studied the expression of perforin and interferon-gamma (IFN-gamma) secretion in these Rta-specific T cells. Our study demonstrated that Rta-specific T cells are capable of IFN-gamma production and nearly 90% of the Rta-specific CD8(+) T cells expressed perforin. Presumably, these are the cells that play an important role in determining the initiation of the lytic cycle or the clearance of EBV.

Delaying Acute Graft-Versus-Host Disease in Mouse Bone Marrow Transplantation by Treating Donor Cells with Antibodies Directed at l-Selectin and alpha4-Integrin Prior to Infusion

Acute graft-versus-host disease (GVHD) is still a major hurdle for successful bone marrow transplantation (BMT). Although many immunosuppressive drugs are available, none of them alone or in combination are able to completely abolish acute GVHD. The lifelong immunosuppression profoundly reduces the quality of life of BMT recipients. Therefore, new therapeutic approaches are needed. We previously reported that, in an acute GVHD model using SCID mice as recipient, incubating donor spleen cells with antibodies directed at CD49d and CD62L could significantly delay the occurrence of acute GVHD. To test the potential usefulness of this treatment in BMT, we examined this therapeutic protocol in a mouse BMT model. The present mouse BMT study confirmed our previous results that incubation of donor cells with antibodies directed at CD49d and CD62L prior to infusion into the recipient can effectively delay acute GVHD, allowing the recipients to recover from the side effects of total body irradiation. This one-time treatment is easy and simple and may be modified for clinical usage.

Associations of HLA microsatellites with rheumatoid arthritis in Singaporean Chinese

Rheumatoid arthritis in Singaporean Chinese has previously been shown to be associated with the DRB1*0405, DRB1*1001 haplotypes and to the DRB1*0901 haplotype when the former two were removed. The present paper focused on eight HLA associated microsatellite markers (TNFa, TNFd, D6S273, TAP1CA, DQCAR, DQCARII, D6S2222, D6S2223) and their allelic associations with Chinese RA. 60 RA patients and 75 healthy controls were studied. It appeared that DQCARII*194/DRB1*0405/TNFa*117 was part of the extended haplotype predisposed to RA, whereas DRB1*0901/D6S273*128 contributed to susceptibility to RA to a lesser degree in Singaporean Chinese. Additionally, a negative association with DQCAR*186/DRB1*0301/D6S273*122/TNFd*124 was observed. No association with disease development was observed in this study.

Meningioma--the Sarawak General Hospital experience

The aim of this study was to determine the factors for the large size of intracranial meningiomas at the time of presentation to the Sarawak General Hospital. The data was collected prospectively from 1/3/2000 to 28/2/2001. During this period a total of 57 cases of intracranial tumours were operated upon. Twenty of these cases (35%) were meningioma, making meningioma the most common intracranial tumour operated in the Neurosurgery service here with one to two cases operated per month. Headache was the most common symptom. The average duration of symptoms before the diagnosis was made was twenty-five months, the longest being fifteen years. The patients needed an average of seven visits prior to the diagnosis.

Involvement of noradrenergic innervation from locus coeruleus to hippocampal formation in negative feedback regulation of penile erection in the rat

We demonstrated previously that a novel negative feed back mechanism for the regulation of penile erection, which is triggered by ascending sensory inputs initiated by tumescence of the penis, exists in the hippocampal formation (HF). This study further elucidated the role of the locus coeruleus (LC), which is the largest aggregate of norepinephrine-containing neurons in the brain and provides the major noradrenergic innervation to the HF, in this process. Adult male Sprague-Dawley rats that were anesthetized and maintained with chloral hydrate were used. The intracavernous pressure (ICP) recorded from the corpus cavernosum of the penis was used as the experimental index for penile erection. Electrical activation of the LC elicited a significant reduction in baseline ICP. Similar observations were obtained on microinjection bilaterally into the hippocampal CA1 or CA3 subfield or dentate gyrus of equimolar doses (5 nmol) of norepinephrine (alpha1-, alpha2-agonist), phenylephrine (alpha1-agonist), or BHT 933 (alpha2-agonist). Bilateral electrolytic lesions of the LC discernibly enhanced the magnitude and/or duration of the elevation in ICP induced by intracavernous administration of papaverine (400 microgram). A potentiation of the papaverine-evoked ICP increase was also observed following pretreatment with bilateral hippocampal application of equimolar doses (250 pmol) of either prazosin (alpha1-, alpha2B-, alpha2C-antagonist), naftopidil (alpha1A/D-antagonist), yohimbine (alpha2-antagonst), or rauwolscine (alpha2B-, alpha2C-antagonist). None of these antagonists, however, affected baseline ICP. These results suggest that noradrenergic innervation of the HF that originates from the LC may play an active role in negative feedback regulation of penile erection, engaging at least alpha1A/D-, alpha2B-, and alpha2C-adrenoceptors in the HF.

T cell infiltration and chemokine expression: relevance to the disease localization in murine graft-versus-host disease

Acute graft-versus-host disease (GVHD) involves mainly skin, liver and intestines. Other organs such as heart, muscle and central nervous system are seldom affected, although their parenchymal cells also express alloantigens, such as MHC class I antigens. The mechanism of this selective involvement of distinct organs in acute GVHD is not well understood. We postulated that it might be related to the selective migration of activated alloreactive T cells. Indeed, T cell infiltration, revealed by examination of serial samples using flow cytometry and immunohistology, occurred early and continuously in the target organs such as the liver, but not in a non-target organ, the heart, in a murine acute GVHD model. Since T cell migration is largely controlled by the expression of chemokine and chemokine receptors, we investigated the chemokine spectrum in target/non-target organs of mice with acute GVHD. We found that in the spleen and liver MIP-1alpha, MIP-2 and Mig were the predominant chemokines expressed. In another target organ, the skin, MIP-1alpha, MIP-2, MCP-1 and MCP-3 were all highly expressed. In a non-target organ of acute GVHD, the heart, the predominant chemokines expressed were MCP-1 and MCP-3. This distinct pattern of chemokine expression in these organs may contribute to the preferential recruitment of inflammatory cells into the liver and skin, but not into the heart, in acute GVHD.

Does intensive rehabilitation improve the functional outcome of patients with traumatic brain injury? Interim result of a randomized controlled trial

To evaluate the effects of intensive rehabilitation on the functional outcome in patients with traumatic brain injury (TBI), we carried out a randomized controlled assessor-blind trial, comparing two groups of patients receiving different intensities of rehabilitation treatment (2 versus 4 h per day). Patients with moderate and severe TBI, aged from 12 to 65 years, were included. Glasgow Outcome Scale (GOS) and Functional Independent Measurement (FIM) were assessed monthly. The interim results of 36 cases showed that there was a trend of more patients in the study group achieving full FIM scores, and good GOS at 2 and 3 months, but the control group appeared to be catching up towards 6 months. Intensive rehabilitation may improve the early functional outcome of TBI patients. The interim results indicate that the study should be continued.

Engagement of inducible nitric oxide synthase at the rostral ventrolateral medulla during mevinphos intoxication in the rat

We evaluated the relationship between the toxicity induced by the organophosphate mevinphos (Mev) and inducible nitric oxide synthase (iNOS) in the rostral ventrolateral medulla (RVLM), the medullary origin of sympathetic neurogenic vasomotor tone. Adult Sprague-Dawley rats that were anesthetized and maintained with propofol were used. Laser scanning confocal microscopic analysis revealed colocalization of the M2 subtype of muscarinic receptors (M(2)R) and iNOS immunoreactivity in RVLM neurons. Comicroinjection bilaterally of Mev (10 nmol) and artificial cerebrospinal fluid (aCSF) into the RVLM elicited a progressive decline in systemic arterial pressure (SAP) and heart rate. This was accompanied during phase 1 Mev intoxication by an increase in the power density of the very high-frequency (VHF; 5-9 Hz), high-frequency (HF; 0.8-2.4 Hz), low-frequency (LF; 0.25- 0.8 Hz) and very low-frequency (VLF; 0-0.25 Hz) components of SAP signals. Phase 2 exhibited a reversal of the VHF and VLF power to control levels and a further reduction in the power density of both HF and LF components to below baseline. Hypotension and bradycardia promoted by Mev were significantly blunted on coadministration into the RVLM of the selective iNOS inhibitors S-methylisothiourea (250 pmol) or aminoguanidine (250 pmol). Not only was the augmented power density of HF and LF components during phase 1 Mev intoxication further enhanced, the reduced power of these two spectral components during phase 2 was appreciably antagonized. On the other hand, the temporal changes in VHF and VLF power were essentially the same as with coadministration of Mev and aCSF. We conclude that, as a cholinesterase inhibitor, Mev may induce toxicity via nitric oxide produced by iNOS on activation of the M(2)R by the accumulated acetylcholine in the RVLM.

The role of ruthenium and rhenium diimine complexes in conjugated polymers that exhibit interesting opto-electronic properties

This paper reports the synthesis and opto-electronic properties of different conjugated polymers that contain the diimine complexes of ruthenium or rhenium. Conjugated poly(phenylene vinylene)s that contain aromatic 1,3,4-oxadiazole and 2,2'-bipyridine units on the main chain were synthesized by the palladium catalyzed olefinic coupling reaction. Other types of polymers based on 1,10-phenanthroline bis(2,2-bipyridyl) ruthenium(II) or chlorotricarbonyl rhenium(I) complexes were also synthesized by the same reaction. In general, these polymers exhibit two absorption bands due to the pi - pi transition of the conjugated main chain and the d-pi* metal-to-ligand charge-transfer transition of the metal complex. As a result, the photosensitivity of the polymers beyond 500 nm was enhanced. Charge-carrier mobility measurements showed that the presence of metal complexes could facilitate the charge-transport process, and the enhancement in carrier mobility was dependent on the metal content in the polymer. In addition, we have also demonstrated that the ruthenium complex could act as both photosensitizer and light emitter. Photovoltaic cells were constructed, and they were subjected to irradiation with a xenon arc lamp. Under illumination, the short circuit current and the open circuit voltage were measured to be 0.05 mAcm(-2) and 0.35 V, respectively. The polymers were fabricated into single-layer emitting devices, and light emission was observed when the device was subjected to forward bias. The maximum luminance was determined to be 300 cdm(-2), and the external quantum efficiency was approximately 0.05 to 0.2%. Although the efficiency was relatively low when compared with other devices based on organic materials, we have demonstrated the first examples of using transition metal complexes for both photovoltaic and light-emitting applications.

Reduced functional expression and molecular synthesis of inducible nitric oxide synthase in rostral ventrolateral medulla of spontaneously hypertensive rats

BACKGROUND

We demonstrated recently that the prevalence of neuronal (nNOS) over inducible (iNOS) nitric oxide synthase activity at the rostral ventrolateral medulla (RVLM), the medullary origin of sympathetic neurogenic vasomotor tone, and the associated dominance of sympathoexcitation over sympathoinhibition underlie the maintenance of sympathetic vasomotor outflow by the endogenous NO. Here, we evaluated the hypothesis that a significant downregulation of iNOS at the RVLM may play a crucial role in the genesis of augmented sympathetic vasomotor tone during hypertension.

METHODS AND RESULTS

Spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats anesthetized with propofol were used. Compared with SHR, the hypotension, bradycardia, or depression in sympathetic vasomotor tone induced by bilateral microinjection of lipopolysaccharide (5 or 10 ng) into the RVLM of WKY rats exhibited significantly shorter-onset latency, appreciably steeper slope, and a greater incidence of mortality. All these effects of lipopolysaccharide (10 ng) were significantly blunted by coadministration of the selective iNOS inhibitor S-methylisothiourea (250 pmol). Reverse transcription-polymerase chain reaction and Western blot analyses further revealed significantly lower iNOS mRNA and protein levels at the ventrolateral medulla in SHR under basal conditions or on activation by lipopolysaccharide (10 ng). Conversely, nNOS mRNA and protein levels remained constant in the RVLM and were comparable in both strains of rats.

CONCLUSIONS

We conclude that a significant downregulation in both functional expression and molecular synthesis of iNOS at the RVLM may underlie the augmented sympathetic vasomotor tone during hypertension.

Antibody response to Epstein-Barr virus Rta protein in patients with nasopharyngeal carcinoma: a new serologic parameter for diagnosis

BACKGROUND

Nasopharyngeal carcinoma (NPC) is associated closely with Epstein-Barr virus (EBV). The authors previously reported that an EBV immediate-early gene, BRLF1, was expressed frequently in NPC tumors, and a significant elevation in immunoglobulin G (IgG) antibodies directed against BRLF1 gene product Rta was detected in NPC sera by a radioactive immunoprecipitation assay. To simplify and to make the detection more quantitative, an enzyme-linked immnunosorbent assay (ELISA) was developed in this study.

METHODS

Antigen domains of Rta were identified further using an immunoprecipitation assay. Two glutathione-S-transferase (GST) recombinant Rta fragments (R150-GST and R185-GST) were prepared subsequently and were used as antigens in the ELISA. Serum samples derived from 51 patients with NPC patients, 115 non-NPC ENT patients, and 47 healthy volunteers were examined for the presence of antibodies directed against Rta.

RESULTS

Among the patients with NPC, 74.5% showed a positive IgG response to R150-GST, and 62.7% showed a positive IgG response to R185-GST, with 80.4% positive for either fragment. In contrast, the reactions were positive in only 8.5% of healthy volunteers and 13.0% of control patients. When using a mixture of the two recombinant Rta proteins as coating antigens, the IgG positive responses were 82.3%, 10.6%, and 14.8%, respectively, in patients with NPC, healthy volunteers, and control patients. It is noteworthy that 51.0% of the NPC sera showed a positive immunoglobulin A (IgA) response, with none of the control patients showing obvious reactivity. Both the IgG response and the IgA response to Rta protein in patients with NPC were correlated with the IgA response to EBV early antigens and virus capsid antigens, the classic serologic markers used to diagnose NPC.

CONCLUSIONS

The ELISA method described for the detection of IgG antibodies directed against recombinant Rta proteins is simple and reliable and may be useful as a serologic parameter for the screening and diagnosis of patients with NPC.

Inhibition of baroreflex by angiotensin II via Fos expression in nucleus tractus solitarii of the rat

We evaluated the modulatory action of angiotensin II at the nucleus tractus solitarii on spontaneous baroreceptor reflex response, the angiotensin subtype receptors involved, and the role of Fos protein in this process, using Sprague-Dawley rats anesthetized with pentobarbital sodium. Microinjection bilaterally of angiotensin (Ang ) II (5, 10, 20, or 40 pmol) into the nucleus tractus solitarii significantly suppressed the spontaneous baroreceptor reflex, as represented by the magnitude of transfer function between systemic arterial pressure and heart rate signals. There also was a concomitant increase in Fos-like immunoreactivity in the nucleus tractus solitarii. Both the suppression of spontaneous baroreceptor reflex and Fos expression in nucleus tractus solitarii neurons elicited by Ang II were discernibly attenuated by pretreatment with or comicroinjection into the bilateral nucleus tractus solitarii of a 15-mer antisense c-fos oligonucleotide that targets against the initiation codon of c-fos mRNA. In addition, those 2 actions of Ang II were reversed by the coadministration of the nonpeptide Ang II type 1 (AT(1)) receptor antagonist losartan (1.6 nmol) but not by the nonpeptide AT(2) receptor antagonist PD 123,319 (1.6 nmol). Control treatments with artificial cerebrospinal fluid, sense cDNA, or antisense oligonucleotide with a scrambled sequence were ineffective. We conclude that under minimal cardiovascular perturbation, Fos expression mediated via activation of AT(1) subtype receptors may underlie the inhibitory modulation of beat-to-beat baroreflex control of blood pressure by Ang II at the nucleus tractus solitarii.

Expression profiles of ErbB family receptors and prognosis in primary transitional cell carcinoma of the urinary bladder

In vitro experiments have demonstrated that epidermal growth factor (EGF)-related peptides activate distinct subsets of ErbB receptors and differ in their biological activities. The implications of cross-talk among ErbB family receptors in human cancer, however, remain to be clarified. This cohort study was performed to examine the expression patterns of ErbB receptors by immunohistochemistry in primary human bladder cancer (n = 245) and compared with conventional biological indicators for their prognostic significance. Expression of individual EGF receptor (EGFR) and ErbB2, ErbB3, or ErbB4 receptors was detected in 72.2, 44.5, 56.3, and 29.8% of bladder cancer cases, respectively. Expression of two of the receptors varied from 14.7 to 42.4%, of three of the receptors between 11.0 and 22.0%, and of all four of the ErbB receptors by 8.6%. Important indicators in association with patient survival were tumor staging (P = 0.017), ErbB2 (P = 0.018), EGFR-ErbB2 (P = 0.023), and ErbB2-ErbB3 (P = 0.042). In the subset of grade-2 tumors, EGFR-ErbB2-ErbB3 and EGFR-ErbB2 predicted the development of second recurrence (P = 0.026 and 0.039, respectively), and ErbB2-ErbB3 tended to correlate with patient survival (P = 0.09). The results indicate that a combination of EGFR, ErbB2, and ErbB3 expression profile may be a better prognostic indicator than any family member alone. Given that ErbB2 is the preferred coexpression partner of ErbB family members, expression of other ErbB receptors may significantly affect the prognostic implication of ErbB2 for bladder cancer patients.

Fos protein is required for the re-expression of angiotensin II type 1 receptors in the nucleus tractus solitarii after baroreceptor activation in the rat

We evaluated in Sprague--Dawley rats the hypothesis that Fos protein induced by baroreceptor activation in the nucleus tractus solitarii participates in transcriptional regulation of the expression of angiotensin receptor genes. Reverse transcription-polymerase chain reaction revealed that baroreceptor activation elicited by sustained hypertension resulted in a transient decrease in angiotensin II subtype 1, but not subtype 2, receptor messenger RNA, in the dorsomedial medulla, including the nucleus tractus solitarii. There was subsequently a transitory reduction in the pressor response elicited by microinjection bilaterally of angiotensin II (40 pmol) into the nucleus tractus solitarii, followed by an increase in c-fos messenger RNA and Fos immunoreactivity at the same nucleus. Both the re-expression of angiotensin II subtype 1 receptor messenger RNA and restoration of pressor response to angiotensin II after baroreceptor activation were significantly blunted by bilateral application into the nucleus tractus solitarii of an antisense oligonucleotide (50 pmol) that targets against the initiation codon of c-fos messenger RNA. Control pretreatment with the corresponding sense oligonucleotide (50 pmol), or an antisense c-fos oligonucleotide that targets against a different portion of the coding sequence of the c-fos messenger RNA (50 pmol), was ineffective. At the receptor level, the angiotensin II-induced pressor response was antagonized by the subtype 1 receptor antagonist losartan (1.6 nmol), but not by the subtype 2 receptor antagonist PD-123319 (1.6 nmol). These findings suggest that sustained hypertension down-regulates angiotensin II subtype 1 receptors at both messenger RNA and functional expression levels in the nucleus tractus solitarii. Furthermore, Fos protein induced in the nucleus tractus solitarii by baroreceptor activation may play a permissive role in the transcriptional regulation of the re-expression of this subtype of angiotensin receptors.

Potentiation of baroreceptor reflex response by heat shock protein 70 in nucleus tractus solitarii confers cardiovascular protection during heatstroke

BACKGROUND

Whereas hypotension and bradycardia seen during the onset of heatstroke may be protected by prior induction of heat shock protein 70 (HSP70) in the brain, the underlying mechanism is not fully understood. We evaluated the hypothesis that HSP70 may confer cardiovascular protection during heatstroke by potentiating the baroreceptor reflex (BRR) control of peripheral hemodynamic performance.

METHODS AND RESULTS

Adult male Sprague-Dawley rats subjected to a brief hyperthermic heat shock (HS; 42 degrees C for 15 minutes) induced discernible expression of HSP70 in the bilateral nucleus tractus solitarii (NTS), the terminal site in the brain stem for primary baroreceptor afferents. This HSP70 expression was detected at 8 hours, peaked at 24 hours, and returned to baseline by 48 hours after HS. Brief hyperthermia also significantly potentiated the BRR response in a temporal profile that correlated positively with changes in HSP70 expression at the NTS. Prior HS also appreciably alleviated hyperthermia, severe hypotension, and bradycardia manifested during the onset of heatstroke (45 degrees C for 60 minutes) elicited 24 hours later. Microinjection bilaterally of anti-HSP70 antiserum (1:20) into the NTS or denervation of the sinoaortic baroreceptor afferents significantly reversed the enhancement of BRR response and cardiovascular protection during heatstroke induced by prior HS.

CONCLUSIONS

These results suggest that HS-induced expression of HSP70 in the NTS may alleviate severe hypotension and bradycardia exhibited during the onset of heatstroke by potentiating both the sensitivity and capacity of BRR response.

Tonic suppression of spontaneous baroreceptor reflex by endogenous angiotensins via AT(2) subtype receptors at nucleus reticularis ventrolateralis in the rat

We evaluated the role of endogenous angiotensins at the rostral nucleus reticularis ventrolateralis (NRVL) in the modulation of spontaneous baroreceptor reflex (BRR) response and the subtype of angiotensin receptors involved using rats anesthetized and maintained with pentobarbital sodium. Bilateral microinjection of angiotensin II (ANG II) or its active metabolite angiotensin III (ANG III) (5, 10, or 20 pmol) into the NRVL significantly suppressed the spontaneous BRR response, as represented by the magnitude of transfer function between systemic arterial pressure and heart rate signals. The inhibitory effect of ANG III (20 pmol) was discernibly reversed by coadministration with its peptide antagonist, [Ile(7)]ANG III (1.6 nmol), or the nonpeptide AT(2) receptor antagonist, PD-123319 (1.6 nmol), but not by the nonpeptide AT(1) receptor antagonist, losartan (1.6 nmol). On the other hand, the peptide antagonist, [Sar(1), Ile(8)]ANG II (1.6 nmol) or both non-peptide antagonists appreciably reversed the suppressive action of ANG II (20 pmol). Whereas losartan produced minimal effect, blocking the endogenous activity of the angiotensins by microinjection into the bilateral NRVL of PD-123319, [Sar(1), Ile(8)]ANG II or [Ile(7)]ANG III elicited significant enhancement of the spontaneous BRR response. We conclude that under physiologic conditions both endogenous ANG II and ANG III may exert a tonic inhibitory modulation on the spontaneous BRR response by acting selectively on the AT(2) subtype receptors at the NRVL.

Evaluation of Etest for direct antifungal susceptibility testing of yeasts in positive blood cultures

The performance of the Etest (AB BIODISK, Solna, Sweden) for direct antifungal susceptibility testing of yeasts in positive blood cultures was compared with that of the macrodilution method for determining the MICs of five antifungal agents. Culture broths with blood from bottles positive for yeasts were inoculated directly onto plates for susceptibility testing with the Etest, and the MICs were read after 24 and 48 h of incubation. A total of 141 positive blood cultures (72 cultures of Candida albicans, 31 of Candida tropicalis, 14 of Candida glabrata, 11 of Candida parapsilosis, 3 of Candida krusei, and 3 of Cryptococcus neoformans, 4 miscellaneous yeast species, and 3 mixed cultures) were tested, and the rates of MIC agreement (+/-1 log(2) dilution) between the direct Etest (at 24 and 48 h, respectively) and macrodilution methods were as follows: amphotericin B, 81.8 and 93.5%; flucytosine, 84.8 and 87.7%; fluconazole, 89.4 and 85.5%; itraconazole, 69.7 and 63.8%; ketoconazole, 87.9 and 79.0%. By a large-sample t test, the difference in log(2) dilution between the direct Etest and the macrodilution method was found to be small (P < 0.05). The lone exceptions were ketoconazole at 48 h of incubation and itraconazole at both 24 and 48 h of incubation (P > 0.05). By Tukey's multiple comparisons, the difference between the direct Etest (48 h) and reference methods among different species was found to be less than 1 log(2) dilution. When the MICs were translated into interpretive susceptibility, the minor errors caused by the direct Etest (at 24 and 48 h, respectively) were as follows: flucytosine, 2.3 and 1.4%; fluconazole, 3.0 and 3.6%; itraconazole, 21.2 and 21.3%. Itraconazole also produced an additional 3.0 and 3.6% major errors as determined by the direct Etest at 24 and 48 h, respectively. It was concluded that, except for itraconazole, the Etest method was feasible for direct susceptibility testing of blood cultures positive for yeasts. The method is simple, and the results could be read between 24 and 48 h after direct inoculation, whenever the inhibition zones were discernible.

Education and cognitive decline in Parkinson's disease: a study of 102 patients

OBJECTIVE

To understand the correlation between low education level (EL) and the cognitive impairment in Parkinson's disease (PD).

PATIENTS AND METHODS

This is a cross-sectional study of cognitive function in 102 non-demented PD patients, from a special clinic (behavioral neurology) in a referral medical center. PD patients were divided into low, middle and high EL groups. We used the Chinese version of the Cognitive Ability Screening Instrument as a neuropsychological test, which covers nine domains of cognitive function. A full score is 100. When determining the abnormality rate of each item of CASI, we used age/education stratified normal control groups as reference to obliterate the influence of education and age on cognitive decline.

RESULTS

Recent memory, language and attention are the three items in which there were differences between the groups, in terms of abnormal performance rates. The high EL group is at less risk of recent memory impairment, but at more risk of impairment in language and attention. The other six items and total score showed no differences among the groups. Thirty-eight percent of the patients had a total score below 1.5 SD of the means of the general population.

CONCLUSION

This study shows that high EL exerts no protective effect on the cognitive decline in PD patients in general, except in recent memory. The rate of cognitive dysfunction in PD patients is high. This deserves more attention.

Trichosanthin interacts with acidic ribosomal proteins P0 and P1 and mitotic checkpoint protein MAD2B

Trichosanthin is a ribosome-inactivating protein with multiple pharmacological properties. By a yeast two-hybrid system, ribosomal phosphoproteins P0 and P1 and a putative mitotic checkpoint protein, MAD2B, were found to interact with an active-site mutated trichosanthin (TCS). The interactions were verified by an in vitro binding assay of recombinant wild-type TCS and target proteins. The interaction domain of P0 was mapped to amino acids 220-273, which had been previously reported to be involved in the interaction with P1 and P2 in yeast. Consistent with our previous finding that the last seven residues of TCS are not essential for an active conformation, the same deletion did not affect the interaction with P0. Our present study suggests that TCS may disrupt the binding of elongation factors to the P-complex, in addition to the well-known N-glycosidase activity for ribosome inactivation.

Dengue seroepidemiology in Singapore

The resurgence of dengue in Singapore since 1986 had been associated with an adult predominance and a very low incidence in children. No study had been carried out to investigate this finding. Here we report a serological study of 1068 children aged 0 to 15 years. There is a significant rise in seroconversion in children aged 6 years and older coinciding with the start of formal schooling. This suggests that there may be a change in the location where dengue is acquired.

Variability in CD34+ cell counts in umbilical cord blood: implications for cord blood transplants

OBJECTIVE

To determine if total nucleated cell counts alone are sufficient for predicting the efficacy of cord blood units for transplant from neonatal umbilical cord blood samples.

METHODS

Umbilical cord blood samples were collected from 200 mothers at delivery and the cord blood units processed. The total nucleated cells and CD34+ cells were enumerated and compared for each sample.

RESULTS

Despite an apparent linear correlation between total nucleated cell counts and CD34+ cell counts, each group of total nucleated cell counts demonstrated a high degree of variation in CD34+ cell counts and could be as low as 0.1% of total nucleated cell counts.

CONCLUSIONS

Large variations in CD34+ cell counts per total nucleated cell count are present for cord blood units from neonatal umbilical cord samples. Hence a CD34+ cell count for each cord blood unit would improve selection of samples for transplant.

Blocking L-selectin and alpha4-integrin changes donor cell homing pattern and ameliorates murine acute graft versus host disease

L-selectin, LFA-1 and alpha(4) integrins play important roles in the homing of naïve T cells into peripheral lymphoid tissues. L-selectin- or LFA-1-deficient lymphocytes cannot effectively home to lymph nodes (LN), and antibody blockade of alpha(4) integrins also hinders lymphocytes homing. The present study was initiated to explore whether it is feasible to ameliorate acute graft-versus-host disease (aGVHD) by modulating the homing process of donor cells in the recipient in a mouse model. Using a fluorescence labeling method, we found that two monoclonal antibodies directed at L-selectin and alpha(4) integrins, respectively, when used in combination, could delay half of the donor C57BL/6J mouse spleen cells homing into the LN of recipient BALB/c mouse 15 h after injection. Spleen cells (1 x 10(7)) derived from C57BL/6J (H-2(b)) mice were injected into each C.B-17 SCID recipient mouse (H-2(d)) with or without prior incubation with 10 microg each of the two antibodies. T cell repopulation in the blood was observed in both groups of mice at a comparable level 14 days after injection of the donor cells. Eight control mice started to show aGVHD signs 7 - 14 days after the injection, and all died by day 31. However, among the ten mice that received the antibody-treated donor cells, two died before day 29, four survived between 36 and 78 days, and the remaining four survived more than 150 days, with two of them aGVHD free. It is apparent that the temporarily reduced lymphocyte homing into LN reduced the alloreactivity of the donor T cells, thus providing a simple way of modifying aGVHD. This novel approach may shed light on the prevention of aGVHD associated with clinical bone marrow transplantation.

Spectral changes in systemic arterial pressure signals during acute mevinphos intoxication in the rat

We investigated the cardiovascular consequences of acute intoxication by the organophosphate poison, mevinphos (Mev), and delineated the underlying mechanism. Based on on-line power spectral analysis of systemic arterial pressure (SAP) signals in rats anesthetized and maintained by propofol, we identified two distinct phases after intravenous administration of Mev (160 or 320 microg/kg). Phase I was characterized by transient hypertension and mild tachycardia, concurrent with an increase in the very high-frequency (BVHF; 5-9 Hz), high-frequency (BHF; 0.8-2.4 Hz), low-frequency (BLF; 0.25-0.8 Hz),and very low-frequency (BVLF; 0-0.25 Hz) components of SAP signals. Phase II exhibited significant hypotension, a reversal of the BVHF and BVLF power to control levels, and further reduction in the power density of both BHF and BLF components to below baseline. Microinjection of Mev (2 microg) into the bilateral nucleus reticularis ventrolateralis (NRVL), the medullary origin of sympathetic neurogenic vasomotor tone, essentially duplicated those phasic cardiovascular changes. Similarly, sympathoexcitatory NRVL neurons exhibited respectively an elevation and a decline in their spontaneous activities during Phase I and Phase II Mev intoxication. We conclude that the progressive accumulation of acetylcholine over time induced by a direct inhibition of Mev on cholinesterase in the NRVL may be responsible for the phasic changes in cardiovascular events over the course of acute Mev intoxication. Whereas the initial amount of acetylcholine is excitatory to NRVL neurons, overstimulation by the amassed acetylcholine results instead of an inhibitory action.

A distinct expression of CC chemokines by macrophages in nasopharyngeal carcinoma: implication for the intense tumor infiltration by T lymphocytes and macrophages

Nasopharyngeal carcinoma (NPC) is characterized by harboring Epstein-Barr virus genes in the tumor cells and an intense infiltration of leukocytes in the tumor tissue. These infiltrating cells are mainly composed of T lymphocytes and macrophages. The mechanism of this intense infiltration has long been a puzzle. We attempted to address this issue by studying the expression of CC chemokines, which are responsible for recruiting both T cells and macrophages, by an immunohistochemical approach. In biopsies obtained from nasopharynx of 17 NPC patients that contained tumor cells, expression of macrophage inflammatory protein 1alpha (MIP-1alpha), MIP-1beta, macrophage chemoattractant protein-1 (MCP-1), MCP-2, MCP-3, and RANTES was detected in the tumor-infiltrating cells, with MIP-1alpha and MCP-1 found in nearly all biopsies and the others relatively less frequently. Furthermore, expression of interferon-gamma (IFN-gamma) was also observed in tumor-infiltrating cells. In contrast, CC chemokines and IFN-gamma were rarely expressed in the 13 control biopsies that were either normal or with nonspecific inflammation, and in 4 biopsies from untreated NPC patients that contained no tumor cells. Using an immunofluorescent double-staining method, MIP-1alpha and MCP-1 were identified to be associated with macrophages, and IFN-gamma with T cells. Moreover, expression of CCR2 and CCR5, the receptors for these chemokines, was also detected in the tumor-infiltrating cells. These data indicate that the intense tumor infiltration by T cells and macrophages is a result of active recruitment. It seems possible that the intense infiltration of leukocytes in NPC tumor tissue is initiated by the activated tumor-reactive T cells. T cells migrate into the tumor tissue in an antigen-specific mode, and IFN-gamma secreted from these pioneer T cells activates tissue macrophages to express CC chemokines, especially MIP-1alpha and MCP-1, which consequently recruit more T cells and macrophages into the tumor tissue.

Differential roles of iNOS and nNOS at rostral ventrolateral medulla during experimental endotoxemia in the rat

We investigated the differential contribution of inducible and neuronal nitric oxide synthase (iNOS and nNOS) at the rostral ventrolateral medulla (RVLM) to endotoxemia induced by E. coli lipopolysaccharide (LPS). In Sprague-Dawley rats maintained under propofol anesthesia, i.v. administration of LPS (15, 30, or 45 mg/kg) induced a reduction (phase I), followed by an augmentation (phase II) and a secondary decrease (phase III) in the power density of the vasomotor components (0-0.8 Hz) in systemic arterial pressure (SAP) signals. LPS also induced an immediate hypotension, followed by a rebound increase and a secondary decrease in SAP. In addition, the level of iNOS mRNA exhibited a significant surge that began with phase I endotoxemia, reaching progressively its peak at phase III. Discernible down-regulation of nNOS mRNA was not detected until the last phase of endotoxemia. Pretreatment with microinjection of the selective iNOS inhibitor, aminoguanidine (250 pmol), into the bilateral RVLM significantly prolonged phases II and III endotoxemia, blunted the initial and secondary hypotension, and antagonized the upregulation of iNOS mRNA. Similar pretreatment with the selective nNOS inhibitor, 7-nitroindazole (1 pmol), on the other hand, discernibly shortened phase II and prolonged phase III endotoxemia, and induced progressive hypotension by antagonizing the rebound increase in SAP. We conclude that the relative prevalence of functional expression and molecular synthesis of iNOS over nNOS in the RVLM may be a crucial determinant for the reduction or loss in power density of the vasomotor components of SAP signals during experimental endotoxemia.

The role of nm23-H1 in the progression of transitional cell bladder cancer

The nm23 gene was initially cloned as a metastasis suppressor gene, but the clinical relevance of nm23-H1 as a metastasis suppressor or prognostic indicator for human cancers remains enigmatic. Given that gene expression is regulated at the tissue-specific level, we studied the molecular mechanisms of nm23-H1 expression in human bladder cancer cell lines and the clinical importance of protein product (NM23-H1) in association with patient outcome (n = 257) by immunohistochemistry. We demonstrated that nm23-H1 is expressed in bladder cancer cells without genomic alterations. High NM23-H1 expression was found in 39 cases (15.2%), intermediate expression in 119 cases (46.3%), and low NM23-H1 in 99 cases (38.5%). NM23-H1 was inversely related to staging classification or tumor size (P < 0.05), with the most significant difference being observed between pTa tumors and those of pT1-pT3 bladder cancer (P = 0.01). Reduced NM23-H1, defined as intermediate and low levels of expression, tended to have a higher risk of tumor metastasis (P = 0.06) or poor longtime survival (P = 0.07). In the subset of grade 2 bladder tumors, reduced NM23-H1 significantly correlated with the occurrence of tumor metastasis or poor patient survival (P < 0.05). These findings overall suggest that nm23-H1 may play an important role in suppressing the early step of carcinogenesis and thus act as an invasion suppressor for human bladder cancer. A prospective study is required to clarify the potential of the molecular marker in prediction of disease progression.