Structured reflection increases intentions to reduce other people's health risks during COVID-19

People believe they should consider how their behavior might negatively impact other people, Yet their behavior often increases others' health risks. This creates challenges for managing public health crises like the COVID-19 pandemic. We examined a procedure wherein people reflect on their personal criteria regarding how their behavior impacts others' health risks. We expected structured reflection to increase people's intentions and decisions to reduce others' health risks. Structured reflection increases attention to others' health risks and the correspondence between people's personal criteria and behavioral intentions. In four experiments during COVID-19, people (N  = 12,995) reported their personal criteria about how much specific attributes, including the impact on others' health risks, should influence their behavior. Compared with control conditions, people who engaged in structured reflection reported greater intentions to reduce business capacity (experiment 1) and avoid large social gatherings (experiments 2 and 3). They also donated more to provide vaccines to refugees (experiment 4). These effects emerged across seven countries that varied in collectivism and COVID-19 case rates (experiments 1 and 2). Structured reflection was distinct from instructions to carefully deliberate (experiment 3). Structured reflection increased the correlation between personal criteria and behavioral intentions (experiments 1 and 3). And structured reflection increased donations more among people who scored lower in cognitive reflection compared with those who scored higher in cognitive reflection (experiment 4). These findings suggest that structured reflection can effectively increase behaviors to reduce public health risks.

Antibiotic prophylaxis in colorectal surgery: are oral, intravenous or both best and is mechanical bowel preparation necessary?

BACKGROUND

The benefit of adding oral antibiotic prophylaxis (OA) to intravenous prophylaxis (IV) in elective colorectal surgery to prevent surgical site infection (SSI) and whether the benefit of OA requires a mechanical bowel cleansing (MBP) are assessed in a systematic review. Meta-analyses compare randomized trials of IV versus IV plus OA, both with MBP; OA versus IV plus OA, both again with MBP; OA plus IV in studies randomizing patients to MBP or no MBP; and IV versus IV plus OA in patients with no MBP.

METHODS

MEDLINE, EMBASE, and the Cochrane Library were searched for eligible studies from 1965 to April 1, 2020. The outcome assessed was SSI, superficial and deep, but not organ space. For each included study, risk of bias was assessed using the Cochrane Risk of Bias tool version 1. For each comparison, meta-analysis was performed from data from eligible studies to obtain a summary effect and heterogeneity using RevMan. Sensitivity analyses were performed excluding studies of poor quality. Certainty of evidence was assessed using GRADE for each comparison.

RESULTS

Sixty-one studies published in 1971-2020 from 55 publications reporting 12,297 patients were eligible for inclusion. A total of 36 studies compared IV to OA plus IV with MBP. The risk ratio (RR) and 95% confidence interval (CI) for SSI with oral and IV vs. IV alone are 0.47, 0.40-0.56. The RR in 19 studies for IV plus OA versus OA alone is 0.48, 0.38-0.62. The RR for OA plus IV with MBP versus without MBP in 5 studies is 1.17, 0.84-1.64. The RR for OA plus IV versus IV alone when no bowel prep was used in two studies is 0.36, 0.18-0.72. RRs were similar in sensitivity analyses. The GRADE is high for the first two comparisons, moderate for the 3rd, and low for the 4th due to imprecision and heterogeneity.

CONCLUSIONS

Combined OA and IV is superior to either alone in preventing SSI. The certainty of evidence is such that further research is unlikely to alter this relationship when MBP is used. In randomized trials of MBP, OA plus IV shows no benefit from MBP versus no MBP. The last comparison shows in just two studies that as in the first meta-analysis, but in the absence of MBP, combined OA plus IV is also superior to IV alone.

Hepatitis C Virus Infection of Cultured Human Hepatoma Cells Causes Apoptosis and Pyroptosis in Both Infected and Bystander Cells

Individuals infected with hepatitis C virus (HCV) are at high risk of developing progressive liver disease, including cirrhosis and hepatocellular carcinoma (HCC). How HCV infection causes liver destruction has been of significant interest for many years, and apoptosis has been proposed as one operative mechanism. In this study, we employed a tissue culture-adapted strain of HCV (JFH1_T) to test effects of HCV infection on induction of programmed cell death (PCD) in Huh-7.5 cells. We found that HCV infection reduced the proliferation rate and induced caspase-3-mediated apoptosis in the infected cell population. However, in addition to apoptosis, we also observed infected cells undergoing caspase-1-mediated pyroptosis, which was induced by NLRP3 inflammasome activation. By co-culturing HCV-infected Huh-7.5 cells with an HCV-non-permissive cell line, we also demonstrated induction of both apoptosis and pyroptosis in uninfected cells. Bystander apoptosis, but not bystander pyroptosis, required cell-cell contact between infected and bystander cells. In summary, these findings provide new information on mechanisms of cell death in response to HCV infection. The observation that both apoptosis and pyroptosis can be induced in bystander cells extends our understanding of HCV-induced pathogenesis in the liver.

A multivariate twin study of hippocampal volume, self-esteem and well-being in middle-aged men

Self-esteem and well-being are important for successful aging, and some evidence suggests that self-esteem and well-being are associated with hippocampal volume, cognition and stress responsivity. Whereas most of this evidence is based on studies on older adults, we investigated self-esteem, well-being and hippocampal volume in 474 male middle-aged twins. Self-esteem was significantly positively correlated with hippocampal volume (0.09, P = 0.03 for left hippocampus, 0.10, P = 0.04 for right). Correlations for well-being were not significant (Ps > 0.05). There were strong phenotypic correlations between self-esteem and well-being (0.72, P < 0.001) and between left and right hippocampal volume (0.72, P < 0.001). In multivariate genetic analyses, a two-factor additive genetic and unique environmental (AE) model with well-being and self-esteem on one factor and left and right hippocampal volumes on the other factor fits the data better than Cholesky, independent pathway or common pathway models. The correlation between the two genetic factors was 0.12 (P = 0.03); the correlation between the environmental factors was 0.09 (P > 0.05). Our results indicate that largely different genetic and environmental factors underlie self-esteem and well-being on one hand and hippocampal volume on the other.

Testosterone modifies the effect of APOE genotype on hippocampal volume in middle-aged men

BACKGROUND

The APOE epsilon4 allele is an established risk factor for Alzheimer disease (AD), yet findings are mixed for how early its effects are manifest. One reason for the mixed results could be the presence of interaction effects with other AD risk factors. Increasing evidence indicates that testosterone may play a significant role in the development of AD. The aim of the present study was to examine the potential interaction of testosterone and APOE genotype with respect to hippocampal volume in middle age.

METHODS

Participants were men from the Vietnam Era Twin Study of Aging (n = 375). The mean age was 55.9 years (range 51-59). Between-group comparisons were performed utilizing a hierarchical linear mixed model that adjusted for the nonindependence of twin data.

RESULTS

A significant interaction was observed between testosterone and APOE genotype (epsilon4-negative vs epsilon4-positive). Those with both low testosterone (> or =1 SD below the mean) and an epsilon4-positive status had the smallest hippocampal volumes, although comparisons with normal testosterone groups were not significant. However, individuals with low testosterone and epsilon4-negative status had significantly larger hippocampal volumes relative to all other groups. A main effect of APOE genotype on hippocampal volume was observed, but only when the APOE-by-testosterone interaction was present.

CONCLUSIONS

These findings demonstrate an interaction effect between testosterone and the APOE epsilon4 allele on hippocampal volume in middle-aged men, and they may suggest 2 low testosterone subgroups. Furthermore, these results allude to potential gene-gene interactions between APOE and either androgen receptor polymorphisms or genes associated with testosterone production.

Natural rates of teacher approval and disapproval in grade-7 classrooms

The natural rates of teacher verbal approval and disapproval in ten grade-seven classrooms were determined and compared with those described by White (1975). Although there were differences in the observation techniques used and the behavioral, cultural, and ethnic groups sampled, the results were similar. The majority of the teachers displayed individual rates of disapproval that were higher than their individual approval rates. The correlations between levels of on-task behavior and approval and disapproval rates were low. The issues raised by these findings are discussed in terms of directions for further research.

Genetic architecture for hole-board behaviors across substantial time intervals in young, middle-aged and old mice

A quantitative trait locus (QTL) analysis of behaviors across the life span was conducted in F(2) mice from a C57BL/6J x DBA/2J cross and 22 BXD recombinant inbred (RI) strains. Mice of three age groups were tested in a hole-board apparatus for 3 min on three occasions approximately 1 month apart (average age at test 150, 450 and 750 days, approximately 400 mice per group, divided equally by sex). Quantitative trait loci with small effect size were found on 11 chromosomes for hole-board activity (Hbact) and hole-board rearing (Hbrear). Analysis of 22 RI strains tested at 150 and 450 days of age found only suggestive linkage, with four QTL for Hbact overlapping with those from the F(2) analysis. There was a significant phenotypic correlation between Hbact and Hbrear (approximately 0.55-0.69) and substantial commonality among QTL for the two behaviors. QTL analyses of head-pokes (HP) and fecal boli (FB) only identified QTL at the suggestive level of significance. Age accounted for approximately 15% of the phenotypic variance (sex approximately 3%), and there were genotype by age interactions at approximately 25% of the Hbact and Hbrear QTL. Quantitative trait loci for Hbrear were relatively stable across the three measurement occasions (those for Hbact somewhat less so), although mean levels of each index declined markedly comparing the first to subsequent trials. Considered as a whole, the polygenic system influencing exploratory behaviors accounts for approximately the same amount of phenotypic variance as age (within the range studied), is stable across substantial periods of time, and acts, for the most part, independently of age and sex.

Harnessing CD36 to rein in inflammation

Maintaining health requires a dynamic balance between the influence of pro-inflammatory and anti-inflammatory mediators. While inflammation serves an important protective role against infection, unrestrained inflammation is acutely lethal and unresolved inflammation contributes to a broad range of chronic disorders. Immunotherapy with cytokines themselves or cytokine antagonists faces strict limitations due to efficacy, safety and cost. More successful treatment of the pro-inflammatory component of chronic disorders may emerge from strategies designed to reset the balance between pro and anti-inflammatory cytokines through physiological regulatory pathways. One emerging avenue for this approach is exploitation of the link between the cell surface protein CD36 and the anti-inflammatory cytokine interleukin-10 (IL-10). Agents that increase CD36 expression and agents that directly bind to CD36 have anti-inflammatory properties that may directly relate to induction of IL-10. The immunosuppressive effects of apoptotic cells were first reported more than a decade ago and have since been tested in animal models and several clinical trials. A recent publication demonstrates that induction of IL-10 by apoptotic cells is largely dependent upon the interaction between apoptotic cells and CD36, the receptor on monocytes and macrophages for apoptotic cells. This provides a direct mechanistic link between CD36 engagement and IL-10 induction, opening up new possibilities for using CD36 ligands, agents that increase CD36 expression or a combination of both to modulate inflammation and treat, or even prevent, an important set of chronic disorders.

Apolipoprotein E genotype and memory in the sixth decade of life

BACKGROUND

Virtually all adult studies of APOE genotypes and cognition have included individuals over 60. In older adults, epsilon 4 carriers may manifest greater cognitive asymmetries than non-epsilon 4 carriers even in the absence of overall mean differences. General cognitive ability may also be affected by aging and APOE genotype, but most studies have inadequately addressed this potential confound. The goals of this study were to examine, in middle age, the relationship of APOE genotype with episodic memory and verbal-visuospatial episodic memory asymmetries, after accounting for prior general cognitive ability.

METHOD

We compared epsilon 4+ and epsilon 4- individuals in 626 male twins in their 50s. We examined verbal and visuospatial episodic memory and verbal-visual asymmetry scores after adjusting for cognitive ability at age 20. Analyses corrected for correlations between twin pair members.

RESULTS

Compared with epsilon 4- individuals, epsilon 4 carriers performed significantly more poorly on verbal, but not visuospatial memory, manifested significantly greater cognitive asymmetry, and also had significantly more concerns about memory. At age 20, epsilon 4 carriers had higher general cognitive ability than epsilon 4- individuals, and current memory differences were enhanced after adjusting for age 20 cognitive ability.

CONCLUSIONS

Small, but significant, APOE-epsilon 4-related memory deficits appear in the sixth decade of life in individuals who show no signs of preclinical dementia. The results partially support studies of older adults that suggest that increased cognitive asymmetries reflect risk for dementia and are associated with the APOE-epsilon 4 genotype. The results also highlight the potential problems of not having accurate data on prior cognitive ability.

Galactography in patients with nipple discharge

Nipple discharge is a common presenting symptom of underlying breast pathology. This study examined the impact of galactography on the evaluation of abnormal nipple discharge. Thirty-five women with spontaneous, unilateral nipple discharge who underwent galactography from 1995 to 1997 were retrospectively studied. Their presenting signs as well as mammographic, galactographic, and pathology findings were evaluated. Nipple discharge was bloody (n = 24), clear (n = 7), or serous (n = 4). A palpable mass was found in 5 patients, and discharge was spontaneous in 29 patients (83%). Mammography was normal in 25 patients (71%). Thirty patients (86%) had an abnormal ductogram that was characterized as a filling defect (n = 20), cutoff sign (n = 5), or ductal dilatation (n = 5). The ductogram demonstrated the location and depth of the lesion in 29 patients (97%). Excision was performed in 27 of 30 patients with an abnormal ductogram: 14 received complete subareolar duct excisions; 12, focused excisions; and 1, excision with a vacuum-assisted biopsy device. Pathology included intraductal papilloma (n = 20) and ductal ectasia (n = 7). Follow-up was completed in 24 patients, including 2 postoperative patients who had persistent discharge on manipulation. In conclusion, galactography is accurate in identifying the location of the ductal abnormality. It allows a focused surgical approach to the pathologic lesion in these patients.

Cross-reactive cytotoxic T lymphocytes against human immunodeficiency virus type 1 protease and gamma interferon-inducible protein 30

The gamma interferon (IFN-gamma)-inducible protein 30 (IP-30) signal peptide -11 to -3 (LLDVPTAAV) is a prominent self peptide expressed with the class I human histocompatibility leukocyte antigen A2 (HLA-A2). Stimulation of peripheral blood mononuclear cells (PBMC) from HLA-A2 human immunodeficiency virus type 1 (HIV-1)-infected individuals with an HLA-A2-restricted HIV protease (PR) peptide 76-84 (LVGPTPVNI) activated cytotoxic T lymphocytes (CTL) against the IP-30 signal peptide. Since HIV-1 PR 76-84 stimulated CD8+ T cells from these individuals to secrete IFN-gamma, we tested whether the activation of IP-30-specific CTL in vitro resulted from T-cell cross-reactivity or from up-regulation of IP-30 by IFN-gamma. Neither high levels of exogenous IFN-gamma nor incubation of PBMC with other HIV peptides triggering substantial IFN-gamma release activated IP-30-specific CTL. Although the IP-30 signal peptide did not stimulate IFN-gamma release from freshly isolated PBMC, it activated CTL in vitro against itself and HIV PR 76-84. Peptide-stimulated IFN-gamma release, cold target inhibition, and HLA-A2/immunoglobulin dimer-mediated binding and depletion of effector cells all indicated that in vitro stimulation with HIV PR 76-84 or the IP-30 signal peptide activated a comparable population of cross-reactive effector cells. Neither IP-30 nor HIV PR 76-84 activated CTL against themselves following in vitro stimulation of PBMC from non-HIV-infected HLA-A2 individuals. Peptide titrations indicated higher-avidity T-cell interactions with HIV PR 76-84 than with the IP-30 signal peptide. These data indicate that HIV PR 76-84 is a heteroclitic variant of the IP-30 signal peptide -11 to -3, which has implications for immune memory and autoimmunity.

Cohort effects in a genetically determined trait: eye colour among US whites

BACKGROUND

While the inheritance of eye colour is likely polygenic, blue eye colour is thought to follow an inheritance pattern similar to that of a recessive trait. Consequently, age-related differences in the prevalence of blue eye colour would be unanticipated.

AIM

This study explores the finding and explanation for birth cohort differences in the prevalence of blue eye colour in the US white population.

SUBJECTS AND METHODS

Data from the first (1971-1975) and third (1988-1994) US National Health and Nutrition Examination Surveys (NHANES-I and NHANES-III), nationally representative surveys of the US population, were analysed. Trends in eye colour prevalence by birth cohort were analysed together with mortality rates according to eye colour. US census data (1980) were examined to explore cohort differences in ancestry and assortative mating by ancestry.

RESULTS

The prevalence of blue eye colour among non-Hispanic whites in NHANES-III was 57.4% (95% CI: 50.1-64.7) for individuals born between 1899 and 1905 compared to 33.8% (95% CI: 31.3-36.5) for those born between 1936 and 1951. No association was found between survival and eye colour, nor was a cohort effect evident for primary ancestry. However, proportions reporting only one ancestry in census data declined with successive birth cohorts.

CONCLUSIONS

A cohort effect in blue eye colour prevalence was found for the US white population. A secular trend of decreasing assortative mating by ancestry is the likely explanation.

HIV-1 DNA burden in peripheral blood CD4+ cells influences disease progression, antiretroviral efficacy, and CD4+ T-cell restoration

Integration of human immunodeficiency virus type-1 (HIV-1) proviral DNA into host cell genomic DNA ensures viral persistence despite suppression of active replication. Because HIV RNA originates from integrated HIV DNA, HIV RNA and DNA loads should interrelate when suppression of viral replication is incomplete. In addition, the link between proviral DNA formation and generation of HIV-1 genetic diversity suggests that the ease with which HIV escapes immune or drug-based suppression should vary with proviral load. Thus, HIV proviral load should have unique prognostic significance independent of the highly labile plasma HIV RNA levels commonly used to monitor patient status. To test this possibility, we developed a simple standardized research assay estimating the proportion of CD4+ peripheral blood mononuclear cells (PBMC) carrying HIV-1 DNA and investigated associations between this parameter, plasma virus load, long-term efficacy of antiretroviral therapy and restoration of CD4+ T cells. Lower proportions of CD4+ PBMC carrying HIV-1 DNA were associated with lower peak plasma HIV RNA levels and with more favorable long-term responses to antiretroviral therapy. These results suggest that HIV proviral load affects both disease progression and responsiveness to antiretroviral therapy. Therefore, new anti-HIV therapies addressing the stable pool of HIV proviral DNA should be developed to improve long-term prospects for suppression of HIV replication.

Fas/FasL-independent activation-induced cell death of T lymphocytes from HIV-infected individuals occurs without DNA fragmentation

We assessed the effects of activation with phorbol myrystic acetate (PMA) and ionomycin on peripheral blood mononuclear cells (PBMC) from HIV-infected individuals by (51)Cr release, propidium iodide (PI) uptake, electron microscopy, and DNA analysis. Up to 70% (51)Cr release was induced from PBMC of HIV-infected individuals, versus up to 26% (51)Cr release from PBMC of non-HIV-infected volunteers. Flow cytometry identified mostly T cells undergoing activation-induced cell death (AICD). The kinetics of (51)Cr release and the effects of cold target inhibitors were consistent with cell-mediated cytotoxicity. Certain anti-CD3 antibodies or extracellular Ca(2+) chelation prevented AICD, but antagonistic anti-Fas antibodies, caspase inhibitors, and cycloheximide had no effect. The antioxidants thiourea and N-acetylcysteine reduced AICD, indicating a role for oxidative stress. Electron microscopy revealed plasma membrane disruption with nuclear integrity, while DNA analysis showed intact chromosomal DNA. This form of T cell AICD triggered by PMA and ionomycin differs from classical apoptosis in the absence of either caspase involvement or DNA fragmentation.

Male inflammatory breast cancer

A case of a 48-year-old male with an inflammatory breast cancer is used to illustrate this uncommon malignancy. The physical examination of thickening and erythema made the clinical diagnosis. Mammographic findings of increased density in the right breast with coarsened stroma and an underlying mass confirmed the clinical findings. The sonographic evaluation revealed a 2-cm ill-defined hypoechoic mass. The pathologic examination of the mastectomy specimen showed an infiltrating duct cell carcinoma with lobular features. Male breast cancer afflicts 1500 men each year. Clinically it must be differentiated from gynecomastia, a much more common and benign condition.

Age-associated diseases and conditions: implications for decreasing late life morbidity

We discuss two types of age-associated diseases; aging-dependent such as Alzheimer's disease and congestive heart failure which increase logarithmically with age, versus age-dependent such as multiple sclerosis and amyotrophic lateral sclerosis which occur at proscribed ages, and then occurrence of new cases ceases or diminishes with further aging. Prevention strategies with both types emphasize postponement or delay of onset. The non-fatal aging-dependent diseases and conditions are an accumulating burden as we age, and increase overall morbidity in late years. These include Alzheimer's disease and other dementias, Parkinson's disease, loss of vision and hearing, incontinence, osteoporosis and hip fracture, osteoarthritis and depression. With mortality postponed, we will be living for many years at old and vulnerable ages. Life's quality will be reasonable for most. Still, increasing the chance that all will experience this desirable outcome requires pursuing the means to delay the onset of the physical and social events which we categorize as the non-fatal aging-dependent diseases and conditions. We must recognize that each added year occurs at the tip of an exponential curve where risk is maximal.

Effectiveness of feeding tubes in nursing home residents with swallowing disorders

BACKGROUND

Among nursing home residents who stop eating, a common decision for residents, caregivers, and families is the decision to begin tube feeding. This study examines the effectiveness of feeding tubes at reducing mortality among nursing home residents with swallowing disorders and feeding disabilities.

METHODS

Data from a version of the Minimum Data Set+ (MDS +) encompassing three different states from calendar years 1993 and 1994 were analyzed. Residents were included in the study if they were not totally dependent on staff for eating upon their first assessment but became totally dependent on staff for eating and had a swallowing disorder at some point during their nursing home stay. We used a proportional hazard regression to examine the relationship of feeding tubes with mortality after total eating dependence occurred.

RESULTS

Unadjusted Kaplan-Meier curves found that those with feeding tubes were less likely to die than comparable residents without feeding tubes (p < .001). Estimated survival at 1 year was 39% for those without feeding tubes and 50% for those with feeding tubes. The multivariate results indicated that feeding tubes were associated with a reduced risk of death (risk ratio, 0.71; 95% confidence interval, 0.59, 0.86).

CONCLUSIONS

This study provides evidence that tube feeding can be life-prolonging, even if the gain in life is not substantial. Such information can be useful to nursing home staff, residents, and families when trying to decide whether to place a feeding tube in a resident with swallowing disorders and eating disabilities.

Reproductive longevity and increased life expectancy

BACKGROUND

Female life expectancy in developed countries has increased by 30 years in the twentieth century.

AIM

To determine if there has been an increase in reproductive longevity.

METHODS

We analysed age-specific fertility data from birth statistics for the USA, Canada, Japan, France, Sweden, the UK and Australia.

RESULTS

Since 1940, birth rates for women aged 35 and over have declined. Among women aged 50 years and older, there has been no increase in births. Fertility rates in 1990 were 0.0 to 0.044 per 1000 women, with total numbers ranging from 0 to 60 births.

CONCLUSION

The fertile years have not been prolonged in the cohort of women whose life expectancy has increased so dramatically this century. This suggests that reproductive senescence is tightly controlled and not extended by factors that enhance female longevity. Other physiological mechanisms may also be fixed within narrow age limits.

Functional and genetic integrity of the CD8 T-cell repertoire in advanced HIV infection

BACKGROUND

HIV-specific cytotoxic T lymphocytes (CTL) can restrict HIV replication in acute and chronic infection, but disease progression occurs in parallel with declining CTL activity. An understanding of why CTL fail to control HIV replication might reveal important mechanisms of disease progression and enhance prospects for developing effective CTL-based immunotherapies.

OBJECTIVES

To investigate the functional integrity, T-cell repertoire diversity, and HIV reactivity of CD8 T lymphocytes in individuals with advanced HIV infection.

METHODS

Individuals were considered to have progressed to advanced HIV infection if their total T-cell count was < 500 x 10(6) cells/(l) on at least two successive clinic visits. CD8 T cells from these individuals were analyzed for CTL function, HIV reactivity and T-cell receptor (TCR) diversity by chromium release assays and reverse transcriptase polymerase chain reaction.

RESULTS

CD8 T cells from all individuals with advanced HIV infection proliferated and differentiated into functional CTL in vitro. Despite extremely low T-cell counts and previous AIDS-defining illnesses, six individuals had inducible anti-HIV CTL responses. In two additional cases, HIV-specific CTL activity became detectable following significant treatment-associated remission of T-cell lymphopenia. Assessment of TCRbetaV gene family representation and betaV gene intrafamily diversity indicated CD8 T-cell repertoire diversity is maintained through advanced HIV infection.

CONCLUSIONS

These data suggest that HIV-specific CTL activity can be selectively compromised while the functional and genetic integrity of the CD8 population as a whole remains intact. A substantial fraction of individuals retain inducible anti-HIV CTL activity through advanced HIV infection and, in at least some cases, effective treatment can restore HIV-specific CTL responses even at this late stage of disease.

Perforin and Fas/Fas ligand-mediated cytotoxicity in acute and chronic woodchuck viral hepatitis

The Fas ligand (FasL)/Fas and the perforin-granzyme cytotoxic pathways presumably play a central role in the development of hepatocellular injury in viral hepatitis. To recognize the potential contribution of FasL and perforin-based cell killing in hepadnaviral infection, we adopted a cytotoxic assay using murine Fas+ P815 and human Fas- K562 cells as targets. Freshly isolated peripheral blood mononuclear cells (PBMC) from woodchucks with newly acquired woodchuck hepatitis virus (WHV) infection (n = 6), with chronic WHV hepatitis (n = 9), and from healthy animals (n = 11) were used as effector cells. We have found that woodchuck lymphoid cells kill cell targets via both the FasL/Fas and the perforin death pathways. The contribution of Fas-dependent cytolysis was ascertained in blocking experiments with anti-Fas antibody and by incubation of PBMC with cyclohexamide to prevent de novo synthesis of FasL. The involvement of the perforin pathway was confirmed by treatment of K562 cells with colchicine to inhibit the microtubule-dependent perforin release. Comparative analysis showed that peripheral lymphoid cells from acute WHV hepatitis, but not those from chronic WHV infection, are more cytotoxic and that this increase seems to be entirely due to activation of perforin-mediated killing. The data indicate that acute infection in woodchucks is associated with the augmented capacity of lymphoid cells to elicit perforin-dependent killing, but in chronic infection, independent of the severity of liver disease and duration of chronicity, these cells have the same or lower cytotoxic potential as PBMC from healthy controls. These findings suggest a role for non-specific cellular immunity, presumably natural killer (NK) cells, in the control of early WHV infection and in the progression of chronic hepatitis.

Differences in locomotor activity across the lifespan of Drosophila melanogaster

The identification of differential patterns of change across the lifespan in quantitative traits is of abiding interest in the biological and gerontological research communities. These differential phenotypic patterns in complex systems illuminate developmental processes and form the foundation for the identification of putative biomarkers of aging. The goal of the present study was to explore changes in locomotor activity through the lifespan of Drosophila melanogaster. A replicated serial cross-sectional sampling design was used to test activity in five genetically independent inbred strains at 7, 14, 21, 28, 35, and 42 days of age. Differences were observed in activity level across ages and strains, suggesting that patterns of activity throughout the lifespan of D. melanogaster are influenced by genetic factors. Observed sex differences in change in activity level indicate that the aging processes may proceed differently in males and females.

Gastrostomy placement and mortality among hospitalized Medicare beneficiaries

CONTEXT

Although the use of feeding tubes among older individuals stirs considerable controversy, population-based descriptive data regarding patient outcomes are scarce.

OBJECTIVE

To describe hospitalized Medicare beneficiaries having gastrostomies placed and their associated mortality rates.

DESIGN

Retrospective cohort study.

SETTING AND PATIENTS

Hospitalized Medicare beneficiaries aged 65 years or older discharged in 1991 following gastrostomy placement (excluding individuals in health maintenance organizations).

MAIN OUTCOME MEASURES

Mortality at 30 days, 1 year, and 3 years following gastrostomy and characteristics of individuals undergoing gastrostomy placement.

RESULTS

In 1991, claims reflecting gastrostomy insertion were submitted for 81105 older Medicare beneficiaries following hospital discharge. The in-hospital mortality rate was 15.3%. Cerebrovascular disease, neoplasms, fluid and electrolyte disorders, and aspiration pneumonia were the most common primary diagnoses. The overall mortality rate at 30 days was 23.9% (95% confidence interval [CI], 23.65%-24.2%), reaching 63.0% (95% CI, 62.7%-63.4%) at 1 year and 81.3% (95% CI, 81.0%-81.5%) by 3 years. One in 131 white and 1 in 58 black Medicare beneficiaries aged 85 years or older was discharged alive or deceased from a hospital in 1991 following gastrostomy placement.

CONCLUSIONS

Gastrostomies are frequently placed in older individuals and more often in blacks; mortality rates following placement are substantial.

Gastrostomies in older patients: the 1990 National Hospital Discharge Survey

BACKGROUND

Although many published case series have described patients' experiences after gastrostomy placement, generalizing from the results of case series can present problems. The purpose of this study was to examine gastrostomy placement among hospitalized older patients in a nationally representative sample.

METHODS

Using the 1990 National Hospital Discharge Survey, age, sex, race, primary and secondary diagnoses, and mortality were described for hospitalized patients aged 65 years and older having gastrostomies. Age-specific placement rates were calculated using mid-1990 Census Bureau population estimates.

RESULTS

In 1990 an estimated 85,400 patients aged 65 years and older were discharged from hospitals with gastrostomies. Frequent primary diagnoses included cerebrovascular disease (19 percent), pneumonia with or without aspiration (12 percent), neoplasm (11 percent), and fluid and electrolyte disorders (9 percent). The in-hospital mortality rate was 16 percent. Age-specific rates for gastrostomy increased from 1.2 per 1000 for those aged 65 to 74 years to 10.8 per 1000 for those aged 85 years and older.

CONCLUSIONS

In 1990 older hospitalized patients had gastrostomies with surprising frequency, and their in-hospital mortality rate was substantial. An estimated 1 percent of the US population aged 85 years and older was discharged from a hospital in 1990 with a gastrostomy.

Evaluation of neoadjuvant chemotherapeutic response of locally advanced breast cancer by magnetic resonance imaging

BACKGROUND

The implementation of new treatment protocols for locally advanced breast cancer is currently limited by inaccurate evaluation of response to neoadjuvant chemotherapy. A recently developed dedicated breast magnetic resonance imaging (MRI) method (RODEO MRI) was evaluated as a tool for determining tumor response and extent of residual disease after neoadjuvant chemotherapy.

METHODS

Thirty-nine patients with Stage II, III, or IV breast carcinoma were prospectively evaluated prior to and following neoadjuvant chemotherapy by MRI, physical examination, and mammography. Assessment of response determined by the three methods was compared. In addition, detailed pathologic correlation of residual disease was determined by serial sectioning of 31 mastectomy specimens from 30 patients. Nine patients had breast conservation, and were included in the response evaluation only. Estimates of tumor response were made by both surgical and medical oncologists. Independent interpretations of MRI studies without knowledge of clinical response were made by three radiologists.

RESULTS

The surgical oncologists assessed complete response (CR), partial response (PR), and no response (NR) in 11, 22, and 7 cases, respectively. The medical oncologists assessed CR, PR, and NR in 12, 21, and 7 cases, respectively. The surgical and medical oncologists' clinical assessment of response agreed with the results of MRI in 52% and 55% of cases, respectively, and with each other in 30 of 40 cases (75%). Mammography correlated with MRI response in only 52% of cases. However, MRI accurately predicted the pathologic determination of residual disease in 30 of 31 cases (97%). There was no disagreement in the assessments of residual disease or response among the three radiologists.

CONCLUSIONS

RODEO breast MRI accurately estimates residual disease after induction chemotherapy. It assesses response to neoadjuvant chemotherapy better than traditional methods of physical examination or mammography. The information obtained from this MRI technique may be used as an objective tool during clinical trials, and to select patients better for breast conservation after neoadjuvant chemotherapy for locally advanced disease.

Similar abnormalities of idiotype and immunoglobulin light chain expression and of cell-mediated cytotoxicity in HIV-infected humans and simian immunodeficiency virus (SIV)-infected rhesus macaques

The pathogenesis of AIDS in simian immunodeficiency virus (SIV)-infected rhesus macaques models the pathogenesis of human AIDS. We investigated whether certain immunological abnormalities associated with HIV infection and implicated in disease progression also occur in SIV infection. We observed striking parallels between the rhesus macaque humoral immune response to SIV and unusual features of the human humoral immune response to HIV infection. Anti-SIV envelope antibodies from SIV-infected macaques exhibited skewed kappa/lambda L chain usage relative to the ratio of kappa/lambda L chain usage detected on total plasma Ig. In addition, the same idiotope conserved on human anti-HIV gag, pol and env antibodies was detected with a similar distribution pattern on macaque anti-SIV env, gag and pol antibodies. Skewed Ig L chain representation and selection of a highly conserved possible dominant regulatory idiotope on antibodies against key neutralizing antigens raise the possibility that the progressive failure of the humoral immune response to SIV and HIV involves skewed oligoclonal humoral immunity. We also found that SIV-infected macaques, like HIV-infected humans, have elevated levels of CD8+ lymphocyte-mediated cytotoxicity. Cytotoxicity against human B cells was higher in CD8+ effector lymphocytes from SIV-infected macaques than in those from uninfected macaques (P < 0.05). Cell-mediated cytotoxicity against human NK cell targets was not elevated in effector lymphocytes from the SIV-infected macaques, suggesting that CTL activity was selectively elevated. Two out of seven SIV-infected macaques tested had CD8+ cytotoxic lymphocytes that selectively killed activated uninfected CD4+ macaque lymphocytes. Oligoclonal B cell responses and persistently elevated CD8+ lymphocyte-mediated cytotoxicity are consistent features of primate retroviral infections leading to AIDS. Understanding immune predispositions to these features triggered by HIV and SIV may advance new prophylactic and therapeutic strategies.

Declining cholesterol and mortality in a sample of older nursing home residents

OBJECTIVE

To examine the association between declining serum cholesterol and mortality in a sample of older nursing home residents.

DESIGN

A retrospective cohort study.

SETTING

A 203-bed nursing home.

PARTICIPANTS

Persons aged 65 and older, resident in the nursing home on January 1, 1988, or admitted through December 31, 1989, were eligible (n = 185) for the study. Follow-up for mortality was conducted until June 30, 1991. Fifty-five survivors with two or more cholesterol levels recorded before January 1, 1990, and the 76 decedents with two or more recorded cholesterol levels constituted the analytic sample (71% of eligible subjects).

OUTCOME MEASURE

Mortality of the nursing home residents.

RESULTS

Cholesterol declined 31.1 mg/dL/yr (95% confidence interval [CI], 19.7 to 42.6) among decedents, versus 4.2 mg/dL/yr (95% CI, -4.9 to 13.2) among survivors. The association between cholesterol decline (absolute or relative rates) and mortality was examined using logistic regression controlling for age, sex, and tube feeding. Compared with a referrent group with no change or increase, declining cholesterol greater than 45 mg/dL/yr was accompanied by an adjusted relative odds for death of 6.2 (95% CI, 2.1 to 18.4); declining cholesterol greater than 20% per year was accompanied by an adjusted relative odds for death of 7.3 (95% CI; 2.4 to 22.2). Extreme declines greater than 20% per year occurred in 47% of decedents but in only 15% of survivors.

CONCLUSION

Precipitously declining cholesterol appeared to be a marker for mortality in the sample and may help explain the low cholesterol-mortality association in older nursing home residents.

Self-reported health and survival in the Longitudinal Study of Aging, 1984-1986

Changing and often declining health among elderly individuals makes interpreting the long-standing association between self-reported health (SRH) and mortality potentially problematic. This analysis of the Longitudinal Study of Aging from 1984 through 1986 explores changes over time in the association between a single self-report of health and survival among 4380 noninstitutionalized individuals aged 70 and older. Health was reported as excellent or very good (excellent/very good), good, fair or poor. The association between SRH and survival was modeled controlling for age, race, education, marital status, body mass index, difficulty performing activities of daily living, social contacts, self-reported stroke, heart disease, cancer, diabetes and recent hospitalization. Among women, SRH and survival were associated in a nonproportional model, with relative hazard declining over time. Women with poor vs excellent/very good SRH had adjusted relative hazards at 5, 14, 23 and 32 months of 3.8 [95% confidence interval (CI) 2.0-7.1], 2.7 (95% CI: 1.8-4.1), 2.0 (95% CI: 1.3-3.0), and 1.4 (95% CI: 0.7-2.7). The declining relative hazard was due to an increasing mortality rate over time among women initially reporting excellent/very good health. SRH was associated with survival among men in a proportional model (constant relative hazard over time). Men with poor vs excellent/very good SRH had an adjusted relative hazard of 1.7 (95% CI: 1.1-2.6) over the entire follow-up. The relative hazard of lesser magnitude among men reflects the weaker SRH-survival association, possibly too weak for any interaction with time to be detected. The constant relative hazard is also consistent with a rapid decline in health before death among men. The diminishing SRH-survival association among women is consistent with their longer period of declining health before death.

Cytotoxic T-lymphocytes that kill autologous CD4+ lymphocytes are associated with CD4+ lymphocyte depletion in HIV-1 infection

Human immunodeficiency virus type 1 (HIV-1)-infected individuals, but not HIV-seronegative controls, have non-HLA-restricted T-cell receptor alpha beta+ CD8+ cytotoxic T-lymphocytes (CTL) that kill activated uninfected CD4+ lymphocytes. In vitro stimulation of peripheral blood mononuclear cells from HIV-1-infected individuals with concanavalin A (Con A) or by coculture with phytohemagglutinin-activated autologous lymphoblasts induced CTL that killed autologous and heterologous CD4+ lymphocytes, but not Con A-activated CD8+ lymphocytes or Epstein-Barr virus (EBV)-transformed B lymphocytes. EBV did not stimulate such CTL in two subjects tested, although stimulation with Con A or autologous lymphoblasts induced CTL activity against CD4+ lymphocytes in both subjects. CTL activity against autologous CD4+ lymphocytes varied over time; killing of heterologous CD4+ lymphocytes was often higher than that of autologous CD4+ lymphocytes. HIV-infected individuals with Con A-inducible CTL against autologous CD4+ lymphocytes lost more CD4+ lymphocytes within 6 months of testing than HIV-infected individuals with no such CTL (p < .01). The mean (+/- SD) decrease in CD4+ lymphocyte counts in a group of HIV-infected individuals with CTL activity against autologous CD4+ lymphocytes was 121 +/- 84, or 36%, of total CD4+ lymphocytes over 6 months. In contrast, there was no significant change in mean CD4+ lymphocyte count over 6 months in a group of HIV-infected individuals without CTL activity against autologous CD4+ lymphocytes. In some HIV-infected individuals, CTL activity against autologous CD4+ lymphocytes fell coincident with a drop in CD4+ lymphocyte number in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)

Lysis of CD4+ lymphocytes by non-HLA-restricted cytotoxic T lymphocytes from HIV-infected individuals

Individuals infected with HIV have elevated numbers of total and activated CD8+ lymphocytes in peripheral blood. CD8+ lymphocytes from HIV-infected individuals have been shown to mediate non-human histocompatibility-linked antigen (HLA)-restricted suppression of viral replication, HLA-restricted killing of cells expressing HIV antigens, and killing of uninfected lymphocytes. We studied CD8+ T lymphocytes that lysed autologous CD4+ lymphocytes. heterologous CD4+ lymphocytes from HIV-infected individuals and uninfected CD4+ lymphocytes. Killing in all cases required T cell receptor (TCR)-mediated recognition or triggering. However, these CD8+ cytotoxic T lymphocytes (CTL) killed HLA class I mismatched CD4+ lymphocytes and CD4+ lymphocytes treated with a MoAb against HLA-A, B and C antigens (PA2.6) which blocks HLA class I-restricted killing. HLA class II-negative CD4+ T lymphoma cells (CEM.NKR) were also killed by anti-CD3 inhibited CTL. Stimulation of peripheral blood lymphocytes (PBL) from HIV-infected individuals, but not uninfected controls, with concanavalin A (Con A) and IL-2, induced non-HLA-restricted TCR alpha beta+, CD8+ CTL which lysed CD4+ lymphocytes. Activation of CD4+ lymphocytes increased their susceptibility to CD8+ CTL-mediated lysis. In HIV infection, a population of non-HLA-restricted CTL which lyse activated CD4+ lymphocytes is expanded. The expansion of CTL with unusual characteristics is interesting, because the stimulus for this expansion is unknown. CTL which recognize activated CD4+ cells could play a role in immune regulation and the pathogenesis of AIDS.

Changes in the cytotoxic T-cell repertoire of HIV-1-infected individuals: relationship to disease progression

The repertoire of antigen-specific receptors expressed on T lymphocytes is shaped by fixed genetic and variable environmental selective pressures. Recent technological advances have enabled the analysis of T-cell receptor (TCR) expression in the context of selective pressures arising through normal immune system development and also through pathological features of disease. The pathological features of acquired immune deficiency syndrome (AIDS) are reflected by selective depletion of particular T lymphocyte subsets and expansion of others. An important question concerning the immunopathogenesis of AIDS is whether or not the perturbation of the CD4+ and CD8+ T-cell subsets following infection with human immunodeficiency virus (HIV) is selective based on TCR variable (V) region gene expression. To address this question, we have functionally analyzed TCR V gene expression on CD8+ cytotoxic T lymphocytes from HIV-1-infected individuals. This was done using monoclonal antibodies against individual TCR V regions to trigger redirected cytolysis in 51Cr release assays. The percent specific lysis induced by each antibody functionally measures the representation of the TCR V region gene product it is specific for. Relative to non-HIV-infected controls and asymptomatic HIV-infected individuals with only moderate CD4 lymphocyte depletion, HIV-infected individuals with low CD4 lymphocyte counts exhibited skewed patterns of TCR V region representation. Therefore, the perturbation within the CD8+ cytotoxic T lymphocyte repertoire in HIV infection appears to be selective based on TCR V region usage, increasingly so as disease progresses. The TCR V genes affected varied between different HIV-infected individuals and skewing detected in functional assays was not always apparent by flow cytometric analysis. These results suggest that HIV infection causes generalized effects on the T-cell repertoire, which are reflected in the relative TCR V gene representation of the CD8+ cytotoxic T lymphocyte population in peripheral blood.

The influence of lymphocyte counts and disease progression on circulating and inducible anti-HIV-1 cytotoxic T-cell activity in HIV-1-infected subjects

OBJECTIVE

To evaluate specific anti-HIV cytotoxic T-lymphocyte (CTL) activity in relation to basic clinical and laboratory parameters used to follow HIV infection.

METHODS

Lymphocytes from HIV-1-infected subjects with different clinical and immunologic features of HIV infection were tested for circulating and inducible anti-HIV CTL activity using autologous B-lymphoblastoid cells infected with recombinant vaccinia viruses expressing the HIV gag, pol and env genes as targets. Anti-HIV CTL were induced by stimulation with HIV-infected autologous lymphoblasts in vitro.

RESULTS

We detected circulating anti-HIV CTL in asymptomatic subjects exclusively and found a significant association (P < 0.01) between CD8+ lymphocyte counts > or = 900/microliters blood and detectable levels of circulating anti-HIV CTL. Subjects with circulating anti-HIV CTL also had a higher mean CD8+ lymphocyte count than those without detectable circulating activity (P < 0.001), but there was no significant difference in mean CD4+ lymphocyte count. CD8+ human histocompatibility leukocyte antigen (HLA) class I-restricted anti-HIV CTL were induced in all HIV-infected subjects tested following stimulation with HIV-infected autologous lymphoblasts in vitro. In subjects without detectable circulating anti-HIV CTL, circulating HLA-DR+ cells contributed to anti-HIV CTL activity induced by stimulation with HIV or concanavalin A in vitro.

CONCLUSIONS

Circulating anti-HIV CTL activity is associated with CD8+ lymphocyte counts > or = 900/microliters. Anti-HIV CTL retain proliferative and functional capacity following in vitro stimulation with HIV and interleukin-2 through all stages of HIV infection. Persistent inducible anti-HIV CTL activity in subjects with advanced HIV disease and without circulating CTL suggests impaired activation and/or proliferation of the CTL in vivo.

Single dose cephalosporin prophylaxis in high-risk patients undergoing surgical treatment of the biliary tract

During June 1985 through October 1986, 292 patients considered to be at high risk for having postoperative complications develop underwent cholecystectomy and were evaluated in a multicenter, randomized, prospective, double-blind study. Risk factors included age greater than 70 years, acute cholecystitis within the previous six months, obstructive jaundice, obesity and diabetes mellitus. One gram of cefamandole was administered intravenously to 144 patients and 148 patients received 1 gram of cefotaxime intravenously 30 minutes prior to skin incision. Culture-proved bactibilia was found in 55 patients and 11 of the patients had choledocholithiasis. Of the risk factors considered to place patients at high risk for postoperative infectious complications, obesity and acute cholecystitis proved to be the more common. However, age greater than 70 years, diabetes mellitus and obstructive jaundice were more significant risk factors predisposing to bactibilia. The most common organisms isolated from the bile and gallbladder intraoperatively were Staphylococcus, Streptococcus and Klebsiella species along with enterococcus, Escherichia coli and diphtheroids. Clinically significant postoperative infections occurred in eight patients, including six patients in the cefamandole group and two patients in the cefotaxime group. Antibiotic concentrations were measured in the serum, muscle, subcutaneous fat, gallbladder and bile, with cefamandole showing statistically significant greater concentrations in bile, gallbladder and muscle tissue. There was no statistical significance between the postoperative infection rates, total period of hospitalization or total hospital charges for each group. Therefore, there is no significant advantage between a single prophylactic dose of cefamandole versus cefotaxime for high-risk patients undergoing biliary tract operation.

Hormone levels in vegetarian and nonvegetarian teenage girls: potential implications for breast cancer risk

Between September 1984 and June 1985, a total of 75 adolescent girls, 35 vegetarians residing in a Seventh-Day Adventist school and 40 nonvegetarians residing in a private non-Adventist boarding school, underwent measurement of their plasma hormone levels in the follicular and luteal phase of their menstrual cycles as well as dietary intake measured by 3-day food records, medical history, height, and weight. There were no significant differences between vegetarians and nonvegetarians in average age of the girls, weight, body mass index, age at menarche, years since the onset of menstruation, or percentage of girls with ovulatory cycles. Vegetarian girls had significantly higher levels of log follicular estradiol [2.00 +/- 0.27 (SD) versus 1.85 +/- 0.27 pg/ml, P less than or equal to 0.05] and luteal dehydroepiandrosterone sulfate (DHS) (1.88 +/- 0.71 versus 1.45 +/- 0.80 microgram/ml, P less than or equal to 0.05) than nonvegetarian girls. Follicular DHS was higher in vegetarians than in nonvegetarians (1.72 +/- 0.79 versus 1.45 +/- 0.95 microgram/ml), but the difference was not significant. The differences in follicular and luteal DHS, but not the difference in log estradiol, were significant (P less than or equal to 0.05) after controlling for ovulation, smoking, and alcohol intake with multivariable regression analysis. There were no significant differences in testosterone or in percentage free estradiol levels between vegetarians and nonvegetarians. Smoking was significantly associated with follicular and luteal DHS and with percentage free follicular estradiol, while alcohol use was significantly and inversely associated with percentage free follicular estradiol after controlling for other variables. The implications for breast cancer risk are discussed.

An idiotypic network model of AIDS immunopathogenesis

Considerations from a network theory of the immune system suggest that human immunodeficiency virus and allogeneic stimuli may act synergistically to cause AIDS. The immune responses to these stimuli include two components that are directed against each other. In some AIDS risk groups other antigens that mimic major histocompatibility complex antigens may substitute for allogeneic stimuli. Implications for the prevention of AIDS are discussed.

Distribution of antibodies against denatured collagen in AIDS risk groups and homosexual AIDS patients suggests a link between autoimmunity and the immunopathogenesis of AIDS

Autoimmunity often precedes the onset of AIDS-related complex or AIDS, and a number of autoantibodies have been described in AIDS patients and persons at risk for AIDS. The presence of such antibodies provokes speculation that autoimmunity is a component of AIDS pathogenesis. We report evidence of an autoantibody (anticollagen) common to all homosexual AIDS patients studied. High titer serum reactivity against collagen was detected in all homosexual AIDS patients, and in HIV+ homosexuals (66%), HIV+ i.v. drug users (38%) HIV- homosexuals (32%), HIV+ transfusion recipients (22%), and HIV+ hemophiliacs (13%), but not in HIV- i.v. drug users, HIV- transfusion recipients, HIV- hemophiliacs, rheumatoid arthritis patients, or controls. Anticollagen reactivity does not correlate with serum IgG levels, so it is not merely a reflection of polyclonal B-cell activation. Titration of anticollagen positive sera typically revealed anticollagen antibody titers 100 times those of normal sera. Affinity purification and immunoblot analysis confirmed the antibody nature of the anticollagen reactivity. The anticollagen antibodies react preferentially with primary determinants of types I and III collagen revealed after heat denaturation. Similar antibodies occur infrequently in rheumatoid arthritis patients, more often on SLE, and frequently in graft vs host disease and lepromatous leprosy. Levels of anticollagen activity in HIV+ i.v. drug users and transfusion recipients correlate with serum beta 2-microglobulin levels, suggesting that those persons with anticollagen antibodies are at greater risk of developing AIDS. This correlation, the fact that anticollagen antibodies occurred in all homosexual AIDS patients tested, and the occurrence of antibodies against denatured collagen in immune disorders with features similar to AIDS suggest these antibodies may be related to disease progression. The association of anticollagen autoantibodies with AIDS and certain other infections and immune disorders may reflect common immunopathogenic features in the etiology of these disorders.

Distribution of antibodies against denatured collagen in AIDS risk groups and homosexual AIDS patients suggests a link between autoimmunity and the immunopathogenesis of AIDS

Autoimmunity often precedes the onset of AIDS-related complex or AIDS, and a number of autoantibodies have been described in AIDS patients and persons at risk for AIDS. The presence of such antibodies provokes speculation that autoimmunity is a component of AIDS pathogenesis. We report evidence of an autoantibody (anticollagen) common to all homosexual AIDS patients studied. High titer serum reactivity against collagen was detected in all homosexual AIDS patients, and in HIV+ homosexuals (66%), HIV+ i.v. drug users (38%) HIV- homosexuals (32%), HIV+ transfusion recipients (22%), and HIV+ hemophiliacs (13%), but not in HIV- i.v. drug users, HIV- transfusion recipients, HIV- hemophiliacs, rheumatoid arthritis patients, or controls. Anticollagen reactivity does not correlate with serum IgG levels, so it is not merely a reflection of polyclonal B-cell activation. Titration of anticollagen positive sera typically revealed anticollagen antibody titers 100 times those of normal sera. Affinity purification and immunoblot analysis confirmed the antibody nature of the anticollagen reactivity. The anticollagen antibodies react preferentially with primary determinants of types I and III collagen revealed after heat denaturation. Similar antibodies occur infrequently in rheumatoid arthritis patients, more often on SLE, and frequently in graft vs host disease and lepromatous leprosy. Levels of anticollagen activity in HIV+ i.v. drug users and transfusion recipients correlate with serum beta 2-microglobulin levels, suggesting that those persons with anticollagen antibodies are at greater risk of developing AIDS. This correlation, the fact that anticollagen antibodies occurred in all homosexual AIDS patients tested, and the occurrence of antibodies against denatured collagen in immune disorders with features similar to AIDS suggest these antibodies may be related to disease progression. The association of anticollagen autoantibodies with AIDS and certain other infections and immune disorders may reflect common immunopathogenic features in the etiology of these disorders.

Cartilage proteoglycan changes in experimental canine osteoarthritis

Articular cartilage contains at least 2 proteoglycans (PGs) which aggregate with hyaluronate: one larger, richer in chondroitin sulphate (CSRPG); the other smaller, relatively richer in keratan sulphate (KSRPG). With maturation the ratio of CSRPG/KSRPG decreases. In order to test the hypothesis that osteoarthritic cartilage contains an increased amount of proteoglycans characteristic of immature cartilage, experimental osteoarthritis (OA) was induced in 11 dogs by transection of the anterior cruciate ligament. Proteoglycan populations were assessed by composite agarose polyacrylamide gel electrophoresis (CAPAGE). The OA cartilage had more proteoglycan and an increased proportion of the slower migrating band on CAPAGE, which corresponds to the CSRPG, supporting the hypothesis that OA cartilage contains an increased amount of proteoglycans characteristic of immature cartilage.

Case report: splenectomy in patients with Hodgkin's disease and marrow hypoplasia

Two patients with Hodgkin's disease and hypoplastic bone marrow underwent splenectomy in an attempt to reverse pancytopenia and to improve chemotherapeutic tolerance. Although the peripheral blood counts were improved, the clinical course was not significantly affected. Infectious complications occurred. This suggests that the peripheral hematologic improvement following splenectomy may not reflect a true improvement in marrow tolerance.