Vaporized nicotine use among patients in HIV care who smoke tobacco: perceived health effects and effectiveness as a smoking cessation tool

Evidence suggests adverse health effects from vaporized nicotine (VN) use, such as electronic "e" cigarettes, and limited efficacy to aid tobacco cessation. People with HIV (PWH) smoke tobacco at higher rates than the general population, with greater morbidity, highlighting the necessity of effective tobacco cessation tools. PWH may be more vulnerable to adverse effects of VN. Using semi-structured 1:1 interviews, we examined health beliefs regarding VN, patterns of use, and perceived effectiveness for tobacco cessation among PWH in HIV care at three geographically diverse U.S. sites. PWH (n = 24) had limited understanding of VN product content or health effects, presuming VN less harmful than tobacco cigarettes (TC). VN failed to adequately replicate the psychoactive effects or desired ritual of smoking TC. Concurrent TC use, and continuous VN use throughout the day, was common. Satiety using VN was elusive, and consumption quantity was difficult to track. VN had limited desirability and durability as a TC cessation tool among the interviewed PWH.

Factors associated with medication nonadherence among Medicare low-income subsidy beneficiaries with diabetes, hypertension, and/or heart failure

BACKGROUND: Previous studies have documented factors influencing medication nonadherence among the Medicare population, but few studies have examined medication nonadherence among the Medicare low-income subsidy (LIS) population. Furthermore, little is known about the factors associated with nonadherence among this population, especially those with prevalent chronic conditions such as type 2 diabetes, hypertension, or heart failure. OBJECTIVE: To examine factors associated with the likelihood of medication nonadherence among Medicare LIS recipients with type 2 diabetes, hypertension, or heart failure. METHODS: This was a retrospective analysis of 2012-2013 Medicare Parts A, B, and D claims (most recent available for this research) linked to the Area Health Resources Files. Beneficiaries aged 65 years or older with continuous Medicare coverage and receiving any LIS were included. Individuals were categorized into full LIS or partial LIS groups. Nonadherence was determined by the proportion of days covered less than 80% for specified oral type 2 diabetes, hypertension, and heart failure medications, as defined by the Pharmacy Quality Alliance. A multivariate logistic regression was used to determine and compare individual-level and community-level characteristics associated with nonadherence among the entire study sample, the full LIS group, and the partial LIS group. RESULTS: The study sample included 505,771 Medicare beneficiaries, with 448,509 (88.7%) receiving full LIS and 57,262 (11.3%) receiving partial LIS. The proportion of individuals nonadherent was higher among the full LIS population (33.2%) than that of the partial LIS population (30.8%). Among the entire population, younger age was associated with nonadherence (OR = 0.98; 95% CI = 0.98-0.99). Men were more likely to be nonadherent than women (OR = 1.12; 95% CI = 1.11-1.14). Compared with non-Hispanic Whites, racial/ethnic minorities had higher nonadherence. Compared with beneficiaries who were non-Hispanic White, the ORs for those who were Black, Hispanic, Asian, and other were 1.41 (95% CI = 1.38-1.43), 1.58 (95% CI = 1.55-1.61), 1.08 (95% CI = 1.05-1.11), and 1.63 (95% CI = 1.56-1.70), respectively. There were higher nonadherence rates among patients living in communities with lower socioeconomic characteristics, such as a metropolitan statistical area (MSA vs non-MSA; OR = 1.05, 95% CI = 1.04-1.07). A higher risk adjustment summary score, indicating worse health status, was associated with an increased likelihood of medication nonadherence (OR = 1.21; 95% CI = 1.20-1.22). These patterns were similar among the full and partial LIS groups. CONCLUSIONS: Individual- and community-level characteristics were associated with the likelihood of medication nonadherence among Medicare LIS recipients with type 2 diabetes, hypertension, or heart failure. These characteristics included younger age, male sex, racial/ethnic minorities, living in lower socioeconomic communities, and a higher risk adjustment summary score. This study provided insight into medication nonadherence within the Medicare LIS population and identified the need to consider these factors when developing future policies to improve medication adherence. DISCLOSURES: This study was funded by the Pharmaceutical Research & Manufacturers of America (PhRMA), which was involved in the preparation and revision of the manuscript. Dougherty is employed by PhRMA. Todor was a PQA-CVS Health Foundation Scholar who was funded to work on this study. Hines is employed by Pharmacy Quality Alliance. Wang reports grants from AbbVie, Curo, Bristol Myers Squibb, and Pfizer, during the time of this study, and fees from the PhRMA Foundation for work on its Heath Outcomes Research Advisor Committee. The other authors have nothing to disclose. This study was presented as a poster at the online 2020 PQA Annual Meeting, May 7, 2020.

Impact and correlates of sub-optimal social support among patients in HIV care

Social support (SS) predicts health outcomes among patients living with HIV. We administered a brief, validated measure of SS, the Multifactoral Assessment of Perceived Social Support, within a patient-reported outcomes assessment of health domains in HIV care at 4 U.S. clinics in English and Spanish (n = 708). In univariate analysis, low SS was associated with poorer engagement in care, antiretroviral adherence, and health-related quality of life; current methamphetamine/crystal use, depression, anxiety, and HIV stigma (all p < 0.001); any use of either methamphetamines/crystal, illicit opioids, or cocaine/crack (p = 0.001), current marijuana use (p = 0.012), nicotine use (p = 0.005), and concern for sexually transmitted infection exposure (p = 0.001). High SS was associated with undetectable viral load (p = 0.031). Multivariate analyses found low SS independently associated with depression (risk ratio (RR) 3.72, 95% CI 2.93-4.72), lower adherence (RR 0.76, 95% CI 0.64-0.89), poor engagement in care (RR 2.05, 95% CI 1.44-2.96), and having more symptoms (RR 2.29, 95% CI 1.92-2.75). Medium SS was independently associated with depression (RR 2.59, 95% CI 2.00-3.36), poor engagement in care (RR 1.62, 95% CI 1.15-2.29) and having more symptoms (RR 1.75, 95% CI 1.44-2.13). SS assessment may help identify patients at risk for these outcomes.

Association Between Medication Adherence and Healthcare Costs Among Patients Receiving the Low-Income Subsidy

OBJECTIVES

Significant literature exists on the effects of medication adherence on reducing healthcare costs, but less is known about the effect of medication adherence among Medicare low-income subsidy (LIS) recipients. This study examined the effects of medication adherence on healthcare costs among LIS recipients with diabetes, hypertension, and/or heart failure.

METHODS

This retrospective study analyzed Medicare claims data (2012-2013) linked to the Area Health Resources Files. Using measures developed by the Pharmacy Quality Alliance, adherence to 11 medication classes was studied among patients with 7 possible combinations of the diseases mentioned. Adherence was measured in 8 categories of proportion of days covered (PDC): ≥95%, 90% to <95%, 85% to <90%, 80% to <85%, 75% to <80%, 50% to <75%, 25% to <50%, and <25%. Annual Medicare costs were compared across adherence categories. A generalized linear model was used to control for patient/community characteristics.

RESULTS

Among patients with only one disease, such as diabetes, patients with the lowest adherence (PDC < 25%) had $3152/year higher Medicare costs than patients with the highest adherence (PDC ≥ 95%; $11 101 vs $7949; P < .05). The adjusted costs among patients with PDC < 25% was $1893 higher than patients with PDC ≥ 95% ($9919 vs $8026; P < .05). Among patients with multiple chronic conditions, patients' adherence to medications for fewer diseases had higher costs.

CONCLUSIONS

Greater medication adherence is associated with lower Medicare costs in the Medicare LIS population. Future policy affecting the LIS program should encourage better medication adherence among patients with chronic diseases.

The new landscape of medication adherence improvement: where population health science meets precision medicine

Despite the known health and economic benefits of medications, nonadherence remains a significant, yet entirely preventable public health burden. Over decades, there have been numerous research studies evaluating health interventions and policy efforts aimed at improving adherence, yet no universal or consistently high impact solutions have been identified. At present, new challenges and opportunities in policy and the movement toward value-based care should foster an environment that appreciates adherence as a mechanism to improve health outcomes and control costs (eg, fewer hospitalizations, reduced health care utilization). Our objective was to provide a commentary on recent changes in the landscape of research and health policy directed toward improving adherence and an actionable agenda to achieve system level savings and improved health by harnessing the benefits of medications. Specifically, we address the complementary perspectives of precision medicine and population health management; integrating data sources to develop innovative measurement of adherence and target adherence interventions; and behavioral economics to determine appropriate incentives.

Prevalence, effectiveness, and characteristics of pharmacy-based medication synchronization programs

OBJECTIVES

The burden of visiting pharmacies to fill medications is a central contributor to nonadherence to maintenance medications. Recently, pharmacies have begun offering services that align prescription fill dates to allow patients to pick up all medications on a single visit. We evaluated the prevalence and structure of synchronization programs and evidence of their impact on adherence and clinical outcomes.

STUDY DESIGN

Mixed-methods approach consisting of semi-structured interviews, data from surveillance activities, and a systematic literature review.

METHODS

We conducted interviews with opinion leaders from nonprofit advocacy organizations and exemplary synchronization programs. Program prevalence was determined using data from regular surveillance efforts. A literature review included Medline, EMBASE, Google Scholar, and general Internet searches.

RESULTS

Synchronization programs exist in approximately 10% of independent, 6% of stand-alone chain, and 11% of retail store pharmacies. The majority of programs include a monthly pharmacist appointment and reminder communication. Programs reported the importance of pharmacist buy-in, technology to track and recruit patients, links to other healthcare services, and flexible solutions for managing costs and communication preferences. Although existing peer-reviewed literature suggests that synchronization improves adherence, more evidence is needed to evaluate its impact on patient-centered outcomes.

CONCLUSIONS

As medication synchronization programs shift directions and compete for patients and payer resources, it will be more important than ever to rigorously evaluate their ability to improve clinical outcomes while also providing the growing number of patients managing multiple chronic conditions with the highest level of patient engagement and consumer choice.

Core-shell polymer nanorods by a two-step template wetting process

One-dimensional core-shell polymer nanowires offer many advantages and great potential for many different applications. In this paper we introduce a highly versatile two-step template wetting process to fabricate two-component core-shell polymer nanowires with controllable shell thickness. PLLA and PMMA were chosen as model polymers to demonstrate the feasibility of this process. Solution wetting with different concentrations of polymer solutions was used to fabricate the shell layer and melt wetting was used to fill the shell with the core polymer. The shell thickness was analyzed as a function of the polymer solution concentration and viscosity, and the core-shell morphology was observed with TEM. This paper demonstrates the feasibility of fabricating polymer core-shell nanostructures using our two-step template wetting process and opens the arena for optimization and future experiments with polymers that are desirable for specific applications.

Infantile refsum disease in four Amish sibs

Infantile Refsum disease (IRD) appears with varying degrees of impaired vision, hearing loss, developmental delays, and neuromotor deficiencies. We report on four Amish sibs with IRD from a consanguineous marriage; biochemical testing supported the diagnosis of IRD. Of particular interest in this sibship are characteristic poorly formed yellow-orange teeth in at least three of the four affected sibs and behavior problems in the affected females.

Undetectable serum prostate-specific antigen associated with metastatic prostate cancer: a case report and review of the literature

A 63-year-old man, who had undergone prostatectomy for prostate cancer that was positive for prostate-specific antigen (PSA) was examined and found to have metastatic disease, proven radiologically and pathologically, but with an undetectable PSA and highly elevated prostatic acid phosphatase (PAP). Prostatic acid phosphatase levels fell in response to chemotherapy but his clinical status continued to deteriorate. A review of the literature is presented and several possible explanations for PSA remaining undetectable in these situations are discussed. The authors conclude that although PSA can be used to monitor the majority of patients postprostatectomy, physicians may still need to rely on clinical suspicion, serum PAP, and bone scan for the detection of recurrent disease.

Effect of music on spatial performance: a test of generality

Previous attempts by various researchers to replicate the enhancement of spatial performance following 10 min. exposure to music have been inconsistent in their findings. In the present study 16 subjects showed reliable improvement on a paper-folding-and-cutting task after listening to Mozart's Sonata for Two Pianos in D major, as employed by others. The enhanced performance was also noted for 16 other subjects after listening to a contemporary selection having similar musical characteristics. In both cases the control procedure included 10 min. of listening to a progressive relaxation tape.

Analysis of 3p allelic loss in papillary and nonpapillary renal cell carcinomas. Correlation with tumor karyotypes

Nonpapillary renal cell carcinomas (RCCs) are characterized by deletions of the short arm of chromosome 3 (3p) and papillary RCCs by increased numbers of selected chromosomes. Although recent molecular genetic studies have reported some papillary RCCs to show loss of heterozygosity (LOH) on 3p, a 3p deletion has not been demonstrated in a papillary RCC by karyotype analysis. To investigate this apparent discrepancy between molecular methods and chromosomal changes in the genetic evaluation of RCC, a series of 13 papillary and nonpapillary RCCs was investigated for 3p LOH by PCR-based restriction fragment length polymorphism (PCR-RFLP) analysis and for 3p and 3q LOH by microsatellite analysis. Karyotypes were obtained in six cases. Loss of 3p but not of 3q alleles was found in 8 of 10 nonpapillary RCCs. The region of overlapping deletion was 3p14--p21, and in six cases the deletion involved 3pter loci. One papillary RCC displayed 3p and 3q LOH, but the tumor had two morphologically normal chromosomes 3 and several trisomies. This indicated that nondisjunction of a chromosome from one parent compensated a whole chromosome loss from the other parent during tumor development. LOH in this papillary RCC constituted a reduction of chromosome 3 alleles to homozygosity, but the karyotype change, consisting of an increased number of whole chromosomes and an absence of a structural chromosome 3 abnormality, is regarded as being more characteristic of papillary than nonpapillary RCC.

DNA ploidy and proliferation heterogeneity in human prostate cancers

DNA ploidy determinations have been shown to have clinical application in predicting disease progression, survival, or response to anti-androgen therapies in prostate carcinomas. Since intra-tumor heterogeneity may have a profound effect on DNA measurements, we determined the frequency of DNA ploidy and proliferation (here S-phase fraction) heterogeneity in early prostatic carcinomas, and estimated the potential impact of heterogeneity on predicting disease course, survival, or response to therapy. Using image and flow cytometric analysis of archival, paraffin-embedded prostate tumors, we measured DNA ploidy in individual foci of prostatic carcinoma in stage T1a, T1b and T1c disease. Image analysis studies included the use of Feulgen stained tissue sections, and a comparison of these results with flow cytometric DNA ploidy determinations on nuclei isolated from the same tumor foci. Flow cytometry was also used to measure DNA Index and tumor S-phase fraction, in some cases using multiparameter analysis of isolated nuclei to determine DNA content and the level of the proliferation-associated antigen, p105. Our results indicate that DNA aneuploid foci of prostate carcinoma are infrequently seen in stage T1a disease (13% of the individuals studied), and that the presence of both DNA diploid and aneuploid foci in the same sample is seen in less than 10% of these individuals. Stage T1b and T1c tumors containing only DNA diploid nuclei are seen, though these are likely most common in low volume, low Gleason grade tumors. By using flow cytometry to compare these results with those using image analysis of the same tumor foci, we demonstrated that the majority (> 75%) of these aneuploid tumors are DNA tetraploid. Our data on prostate tumor S-phase fractions indicate that DNA diploid tumors generally have a lower S-phase than DNA aneuploid foci (including comparisons of DNA diploid and aneuploid foci in the same prostate tumor). These results support the model that early prostate tumors are DNA diploid and have a low S-phase, and that these tumors likely evolve to DNA tetraploid tumors with a similar low S-phase fraction.

Snow blowing and shoveling in normal and asymptomatic coronary artery diseased men

We evaluated the oxygen uptake and heart-rate responses to self-paced snow blowing and snow shoveling in 10 men with asymptomatic coronary artery disease, 10 older normal men, and six younger normal men. Mean peak treadmill oxygen uptake in the three groups ranged from 26.4 +/- 1.1 to 47.3 +/- 3.9 ml/kg per min (P < 0.05). Oxygen uptake during snow blowing did not differ significantly among subject groups; values were 17.1 +/- 1.3, 17.7 +/- 1.1, and 17.2 +/- 0.9 ml/kg per min in the coronary artery disease, older normal, and younger normal groups, respectively. Oxygen uptake with snow shoveling was lower (P < 0.05) in those with coronary artery disease (18.4 +/- 1.0 ml/kg per min) than in the normal groups. In comparison with snow shoveling, oxygen uptake and heart rate did not differ (P = NS) from snow blowing in the coronary artery disease group but were lower (P < 0.05) with snow blowing in the two normal groups. The results indicate that men with asymptomatic coronary artery disease and relatively good functional work capacity perform snow blowing and snow shoveling at similar levels of oxygen uptake and heart rate.

Cardiac response to combined moderate heat and exercise in men with coronary artery disease

The effect of moderate heat stress on cardiac performance during sustained moderate physical work was evaluated in men greater than or equal to 6 weeks after a cardiac event. Subjects (n = 10) performed upright leg cycle ergometer exercise at approximately 50% of peak oxygen uptake for up to 60 minutes in warm (30.0 +/- 0.9 degrees C) and thermoneutral (21.5 +/- 0.3 degrees C) environments. Cardiac output (carbon dioxide rebreathing method), left ventricular ejection fraction and relative left ventricular end-diastolic volume (portable nuclear VEST monitor) were periodically determined. In both environments, heart rate increased (p less than 0.05), stroke volume decreased (p less than 0.05), and cardiac output remained unchanged with exercise time. In the warmer environment, heart rate was increased (p less than 0.05) and stroke volume tended to be decreased (p less than 0.08), with no difference in cardiac output. In both environments, left ventricular ejection fraction did not change from minute 6 to 60 of exercise, whereas relative left ventricular end-diastolic volume decreased (p less than 0.05) with exercise time. Arterial blood pressure was unchanged from minute 6 to 60 in the warm environment. Arrhythmias were not altered by exercise time or environment, and no subjects had evidence of myocardial ischemia. The data indicate that although heart rate increased and stroke volume and relative left ventricular end-diastolic volume decreased with exercise time, cardiac output and left ventricular ejection fraction remained unchanged in both thermoneutral and warm environments.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunologic parameters of response in patients with rheumatoid arthritis treated with cyclosporin A

Thirty-one patients with seropositive rheumatoid arthritis treated with cyclosporin A (CsA) were evaluated for immune function prior to, during, and after 1 year of therapy. Patients whose pretreatment peripheral blood mononuclear cells were hypoproliferative in vitro to soluble recall antigens responded better clinically to CsA treatment than did the other patients. During therapy, proliferative responses became normal and remained so until 1-2 months after CsA was discontinued. At that time, the lymphocyte proliferation defect reappeared. In addition, patients who responded clinically to CsA had a higher percentage of Leu-7+ natural killer cells in their peripheral blood prior to therapy. All patients exhibited greater frequencies of cells that expressed interleukin-2 receptors, which decreased with CsA treatment. The clinical response to CsA appears to be associated with distinct immunologic parameters in rheumatoid arthritis.

A review of management of ingrown toenails and onychogryphosis

The purpose of this paper is to propose a rational treatment protocol according to basic surgical principles, anatomy of the nail bed, and etiological factors. Ingrown toenails have been discussed in medical literature for more than 1300 years. The condition commonly affects young adults and may result in significant morbidity in terms of loss of days from work, education, and recreation. The anatomy and physiology of the nail bed are presented to promote better selection of the proper management procedure. Ingrown toenails can be classified in terms of congenital or acquired causes. A surgical protocol, along with a description of each surgical technique, is supplied. The pathology of onychogryphosis is classified in terms of involvement of the germinal matrix, the sterile matrix, or both. Treatment is determined by the severity and underlying medical condition of the patient.

Transforming growth factor-beta is a potent immunosuppressive agent that inhibits IL-1-dependent lymphocyte proliferation

Transforming growth factor-beta (TGF-beta), a product of neoplastic and hemopoietic cells, is a bifunctional regulator of the immune response. At femtomolar concentrations, TGF-beta stimulates monocyte migration, and picomolar quantities induce synthesis of monocyte growth factors, including IL-1, that may promote tissue repair by regulating fibrosis and angiogenesis. Paradoxically, TGF-beta at picomolar concentrations also blocks the ability of IL-1 to stimulate lymphocyte proliferation. At 0.01 to 1.0 ng/ml, TGF-beta 1 and its homologue, TGF-beta 2, suppress the IL-1-dependent murine thymocyte proliferation assay. TGF-beta also inhibits human peripheral blood T lymphocyte mitogenesis. Inhibition of cell division appears to occur after activation of the lymphocytes inasmuch as neither gene expression nor translation of IL-2R is suppressed. Furthermore, TGF-beta does not block synthesis of IL-2. Therefore, TGF-beta 1 and TGF-beta 2 likely act at a site distal to IL-1 to block lymphocyte DNA synthesis. These findings suggest that TGF-beta secreted in an inflammatory site may be beneficial in diminishing lymphocyte function while promoting fibrosis and tissue repair. However, TGF-beta generated by neoplastic tissues may provide a mechanism for unrestricted tumor cell growth through its selective immunosuppressive effects.

Transforming growth factor-beta is a potent immunosuppressive agent that inhibits IL-1-dependent lymphocyte proliferation

Transforming growth factor-beta (TGF-beta), a product of neoplastic and hemopoietic cells, is a bifunctional regulator of the immune response. At femtomolar concentrations, TGF-beta stimulates monocyte migration, and picomolar quantities induce synthesis of monocyte growth factors, including IL-1, that may promote tissue repair by regulating fibrosis and angiogenesis. Paradoxically, TGF-beta at picomolar concentrations also blocks the ability of IL-1 to stimulate lymphocyte proliferation. At 0.01 to 1.0 ng/ml, TGF-beta 1 and its homologue, TGF-beta 2, suppress the IL-1-dependent murine thymocyte proliferation assay. TGF-beta also inhibits human peripheral blood T lymphocyte mitogenesis. Inhibition of cell division appears to occur after activation of the lymphocytes inasmuch as neither gene expression nor translation of IL-2R is suppressed. Furthermore, TGF-beta does not block synthesis of IL-2. Therefore, TGF-beta 1 and TGF-beta 2 likely act at a site distal to IL-1 to block lymphocyte DNA synthesis. These findings suggest that TGF-beta secreted in an inflammatory site may be beneficial in diminishing lymphocyte function while promoting fibrosis and tissue repair. However, TGF-beta generated by neoplastic tissues may provide a mechanism for unrestricted tumor cell growth through its selective immunosuppressive effects.

T lymphocyte-dependent evolution of bacterial cell wall-induced hepatic granulomas

Injection of streptococcal cell walls (SCW) i.p. into susceptible rats results in dissemination of SCW primarily to the liver, spleen, bone marrow, and peripheral joints. Within the liver, the SCW are phagocytized by the Kupffer cells, initiating a sequence of events leading to the formation of hepatic granulomas. The granulomas are characterized by large numbers of W3/13+, W3/25+ T lymphocytes and Ia+, esterase-positive macrophages. The generation of inflammatory mediators by these mononuclear cells appears to be central to the evolution of the granulomas and the subsequent fibrotic sequelae evoked by the SCW. In the absence of functional T lymphocytes (athymic rats), injection of SCW does not trigger lymphokine production, and organized granulomas do not develop in the livers. Furthermore, inhibition of T lymphocyte proliferation and lymphokine synthesis pharmacologically by cyclosporin A administration in euthymic animals inhibits SCW-induced hepatic granuloma development. Although macrophage function is apparently not impaired as evidenced by IL 1 and PGE2 production, a chronic inflammatory response to SCW cannot be sustained in the absence of T lymphocyte participation. These studies provide insight into the cellular and molecular mechanisms leading to formation and maintenance of chronic granulomatous lesions.

T lymphocyte-dependent evolution of bacterial cell wall-induced hepatic granulomas

Injection of streptococcal cell walls (SCW) i.p. into susceptible rats results in dissemination of SCW primarily to the liver, spleen, bone marrow, and peripheral joints. Within the liver, the SCW are phagocytized by the Kupffer cells, initiating a sequence of events leading to the formation of hepatic granulomas. The granulomas are characterized by large numbers of W3/13+, W3/25+ T lymphocytes and Ia+, esterase-positive macrophages. The generation of inflammatory mediators by these mononuclear cells appears to be central to the evolution of the granulomas and the subsequent fibrotic sequelae evoked by the SCW. In the absence of functional T lymphocytes (athymic rats), injection of SCW does not trigger lymphokine production, and organized granulomas do not develop in the livers. Furthermore, inhibition of T lymphocyte proliferation and lymphokine synthesis pharmacologically by cyclosporin A administration in euthymic animals inhibits SCW-induced hepatic granuloma development. Although macrophage function is apparently not impaired as evidenced by IL 1 and PGE2 production, a chronic inflammatory response to SCW cannot be sustained in the absence of T lymphocyte participation. These studies provide insight into the cellular and molecular mechanisms leading to formation and maintenance of chronic granulomatous lesions.

Association of a low molecular weight helper factor(s) with thymocyte proliferative activity

Human mixed leukocyte supernatants contain thymocyte proliferative activity (TPA) and a low m.w. helper factor, designated HP-1, which is capable of partially restoring the antibody response of T-cell-deficient adherent murine spleen cells to the thymic-dependent antigen, SRC. TPA and HP-1 appear to have a comparable m.w. (14,000 to 14,500 daltons) by Sephadex gel filtration column chromatography. Furthermore, HP-1 and TPA exhibit similar patterns of heterogeneity on DEAE-cellulose chromatography, elute together on CM-cellulose chromatography, and manifest identical patterns of migration on polyacrylamide gel electrophoresis. These data suggest that the TPA and HP-1 activities reside in either the same molecule(s) or in different molecules with identical charge/mass ratios. Furthermore, the results support the hypothesis that the helper activity of HP-1 is derived from its capacity to activate T and/or pre-T cells.

Effect of initial storage at room temperature on human red blood cell ATP, 2,3-DPG, and viability

The concentrations of ATP and 2,3-DPG and post-transfusion viability were measured in human red blood cells exposed for one, four and seven hours to room temperature before refrigerated storage for 21 days. No effect of room temperature storage was observed on ATP or viability. Decrease in 2,3-DPG was accelerated by room temperature exposure but the differences in 2.3-DPG were small and unlikely to have a significant adverse effect on red blood cell oxygen delivery. Delays of up to seven hours in refrigeration of blood do not appear to have serious adverse effects on red blood cell viability or function.

Absolute macrophage dependency of T lymphocyte activation by mitogens

A T lymphocyte subpopulation that contains only 0.3% macrophages and less than 2% B lymphocytes has been prepared from guinea pig lymph node cells by the use of two different types of adherence columns. This subpopulation does not porliferate in response to the mitogens Con A or PHA unless additional macrophages are added. The means by which macrophages restore T cell responsiveness to PHA has been investigated. Marcophages appear to function via two different distinct mechanisms in this experimental situation. The first mechanism involves the binding of PHA to the macrophage followed by the "presentation" of the mitogen to the T lymphocyte in a manner that induces cell activation. This presentation function requires that the macrophage be viable and metabolically active. The second mechanism by which macrophages function is by the elaboration of a soluble factor or factors. The presence of these factors has been reliably and reproducibly demonstrated by using a double-chambered, Marbrook-type tissue culture vessel. This soluble factor can induce activation of T lympohcytes with surface bound PHA in the apparent absence of any form of macrophage presentation. In contrast, the function of this factor is clearly distinct from that of the reducing agent, 2-mercaptoethanol, (2-ME) since 2-ME does not enable this T cell subpopulation to be activated by mitogens. On the basis of these observations, we propose that two distinct signals are required to activate this T lymphocyte subpopulation. One signal is delivered by the interaction of the mitogen with the T cell surface, and the second signal is delivered by a soluble factor(s) produced by macrophages. Whether all types of T lymphocytes require two signals to be activated, remains to be established.