Effects of cannabis on lung function: a population-based cohort study.

The effects of cannabis on lung function remain unclear and may be different from those of tobacco. We compared the associations between use of these substances and lung function in a population-based cohort (n = 1,037). Cannabis and tobacco use were reported at ages 18, 21, 26 and 32 yrs. Spirometry, plethysmography and carbon monoxide transfer factor were measured at 32 yrs. Associations between lung function and exposure to each substance were adjusted for exposure to the other substance. Cumulative cannabis use was associated with higher forced vital capacity, total lung capacity, functional residual capacity and residual volume. Cannabis was also associated with higher airway resistance but not with forced expiratory volume in 1 s, forced expiratory ratio or transfer factor. These findings were similar among those who did not smoke tobacco. In contrast, tobacco use was associated with lower forced expiratory volume in 1 s, lower forced expiratory ratio, lower transfer factor and higher static lung volumes, but not with airway resistance. Cannabis appears to have different effects on lung function from those of tobacco. Cannabis use was associated with higher lung volumes, suggesting hyperinflation and increased large-airways resistance, but there was little evidence for airflow obstruction or impairment of gas transfer.

Associations between birth weight, early childhood weight gain and adult lung function.

BACKGROUND: Low birth weight is associated with lower values for spirometry in adults but it is not known if birth weight influences other measures of pulmonary function. It is also unclear whether postnatal growth affects adult lung function. The associations between birth weight, postnatal growth and adult lung function were assessed in an unselected birth cohort of 1037 children. METHODS: Birth weight, weight gain between birth and age 3 years, and lung function at age 32 years were measured. Analyses were adjusted for adult height and sex and further adjusted for multiple other potential confounding factors. RESULTS: Birth weight was positively correlated with spirometric (forced expiratory volume in 1 s and forced vital capacity) and plethysmographic (total lung capacity and functional residual capacity) lung function and with lung diffusing capacity. These associations persisted after adjustment for confounding factors including adult weight, exposure to cigarette smoke in utero and during childhood, personal smoking, socioeconomic status, asthma and gestational age. Weight gain between birth and age 3 years was also positively associated with lung diffusing capacity, and with higher values of lung volumes in men after adjustment for covariates. Neither birth weight nor postnatal weight gain was associated with airflow obstruction. CONCLUSIONS: Low birth weight and lower weight gain in early childhood are associated with modest reductions in adult lung function across a broad range of measures of lung volumes and with lower diffusing capacity. These findings are independent of a number of potential confounding factors and support the hypothesis that fetal and infant growth is a determinant of adult lung function.

A single strand conformation polymorphism study of CD40 ligand. Efficient mutation analysis and carrier detection for X-linked hyper IgM syndrome.

Mutations in the gene for CD40 ligand are responsible for the X-linked form of hyper IgM syndrome. However, no clinical or laboratory findings that reliably distinguish X-linked disease from other forms of hyper IgM syndrome have been reported, nor are there tests available that can be used to confidently provide carrier detection. To identify efficiently mutations in the gene for CD40 ligand, eight pairs of PCR primers that could be used to screen genomic DNA by single strand conformation polymorphism (SSCP) were designed. 11 different mutations were found in DNA from all 13 patients whose activated T cells failed to bind a recombinant CD40 construct. The exact nature of four of these mutations, a deletion and three splice defects, could not be determined by cDNA sequencing. In addition, SSCP analysis permitted rapid carrier detection in two families in whom the source of the mutation was most likely a male with gonadal chimerism who passed the disorder on to some but not all of his daughters. These studies document the utility of SSCP analysis for both mutation detection and carrier detection in X-linked hyper IgM syndrome.

TATA-dependent and TATA-independent function of the basal and heat shock elements of a human hsp70 promoter.

We have characterized the interactions between the TATA element and other sequence elements of a human heat shock protein 70 (hsp70) promoter by a mutational approach. Expression of a distal element of this promoter requires an intact TATA element in human cell lines. The hsp70 TATA element can be functionally replaced for this interaction by TATA elements from the simian virus 40 early and adenovirus EIIa promoters. The TATA element in this promoter therefore both determines the appropriate start site and determines strength by allowing function of the distal element. In contrast, three proximal upstream elements necessary for basal and heat-regulated transcription have no requirement either for a TATA element or for any other proximal element. The behavior of promoters multiply mutant in these proximal elements implies that these elements function independently. We examined the interaction between the heat shock element (HSE) and the TATA element as the distance between the two factor-binding sites was increased. It was necessary to create a mutant HSE with an extended consensus sequence in order for the HSE to function at a distance. Moving this extended HSE 500 bases upstream did not increase its dependence on the TATA element, suggesting that the TATA independence of this element is intrinsic to its function and is not determined by distance from the promoter.

Multiple basal elements of a human hsp70 promoter function differently in human and rodent cell lines.

The human heat shock protein 70 (hsp70) gene is expressed constitutively in a wide variety of cells. Two separate promoter domains determine this basal level of hsp70 expression. The proximal domain is contained within 84 bases of the transcription initiation site and consists of three elements which appear to interact with the TATA factor(s) and CCAAT-box-binding transcription factor and SP1, respectively. The proximal domain is sufficient for near-maximal basal expression to rodent cell lines. The distal promoter domain consists of sequences upstream of -84 and is necessary in conjunction with the proximal domain for full basal expression in human cell lines. Although in BALB/c 3T3 cells the distal promoter domain plays little role in basal expression, it is functional as evidenced by the ability to compensate efficiently for mutations in the proximal CCAATC homology. The distal domain does not compensate as efficiently for proximal-domain mutations in HeLa cells. Basal expression of this human hsp70 promoter is, therefore, determined by multiple elements. Fewer elements are required for basal expression in rodent cell lines than in human cell lines, suggesting that there are significant differences between the rodent and human transcription apparatuses.

Evaluation of Attenuated Tumor Antigens and the Implications for Peptide-Based Cancer Vaccine Development.

INTRODUCTION: Peptide vaccines offer anti-tumor efficacy with very low toxicity. However, repeat stimulation with an immunogenic peptide leads to activation induced cell death (AICD), decreasing efficacy. We engineered variants of an immunogenic peptide (E39) and tested their ability to induce a robust, sustainable immune response. METHODS: Multiple variants of E39 were created by exchanging 1 or 2 amino acids. We tested the PBMC proliferation, cytokine production and cytolytic activity induced by each variant peptide. RESULTS: Repeated stimulation with E39 likely led to in vitro AICD, while stimulation with E39' led to T-cell proliferation with less evidence of AICD, modest cytokine production and high CTL activity. CONCLUSIONS: E39' appears to be the optimal variant of E39 for inducing effective long-term immunity.

MR1-restricted mucosal-associated invariant T (MAIT) cells respond to mycobacterial vaccination and infection in nonhuman primates.

Studies on mucosal-associated invariant T cells (MAITs) in nonhuman primates (NHP), a physiologically relevant model of human immunity, are handicapped due to a lack of macaque MAIT-specific reagents. Here we show that while MR1 ligand-contact residues are conserved between human and multiple NHP species, three T-cell receptor contact-residue mutations in NHP MR1 diminish binding of human MR1 tetramers to macaque MAITs. Construction of naturally loaded macaque MR1 tetramers facilitated identification and characterization of macaque MR1-binding ligands and MAITs, both of which mirrored their human counterparts. Using the macaque MR1 tetramer we show that NHP MAITs activated in vivo in response to both Bacillus Calmette-Guerin vaccination and Mycobacterium tuberculosis infection. These results demonstrate that NHP and human MR1 and MAITs function analogously, and establish a preclinical animal model to test MAIT-targeted vaccines and therapeutics for human infectious and autoimmune disease.

Pre-B acute lymphoblastic leukemia with b3a2 (p210) and e1a2 (p190) BCR-ABL fusion transcripts relapsing as chronic myelogenous leukemia with a less differentiated b3a2 (p210) clone.

The Philadelphia chromosome translocation t(9;22)(q34;q11) may give rise to different BCR/ABL fusion mRNAs due to different genomic breakpoints and alternative splicing. The e1a2, b2a2 or b3a2 and c3a2 fusion mRNAs encode distinct fusion proteins (p190, p210 and p230, respectively), which are associated with different forms of leukemogenesis in humans and animal models. Our patient presented with acute pre-B cell lymphoblastic leukemia (ALL) with normal cytogenetics. After 3 years of standard ALL therapy, he relapsed with t(9;22)-positive chronic myelogenous leukemia (CML). Retrospective molecular analyses of the pre-treatment pre-B cell ALL sample showed the b3a2 (p210) and e1a2 (p190) BCR/ABL fusion transcripts. Only the b3a2 (p210) transcript was detected at relapse. Southern and immunoglobulin heavy chain (IgH) analyses of the presentation and relapse samples revealed an identical BCR rearrangement in both samples. However, only the ALL sample harbored an IgH gene rearrangement. These findings show a clonal relationship between the more differentiated pre-B cell and less differentiated CML clones and that the p210 and p190 fusion mRNAs were alternatively spliced from a single genomic breakpoint. Our patient's unusual molecular findings provide circumstantial evidence that the p190 protein may promote a more differentiated phenotype in a comparatively less differentiated p210-transformed precursor cell.

Cost-conscious prescribing of nonsteroidal anti-inflammatory drugs for adults with arthritis. A review and suggestions.

Salicylates and nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used for the treatment of painful disorders. This article reviews the efficacy, side effects, and costs of these agents and proposes a practical approach to using them in a cost-effective manner. Although there may be some differences in efficacy among available drugs, these do not appear sufficient to justify using the more expensive agents in most cases. Adverse effects, especially gastrointestinal (GI), add to the cost of using these drugs. Aspirin and all nonsalicylate NSAIDs share a risk of causing gastric ulcer, upper GI bleeding, and GI perforation. Prostaglandin inhibition by these agents may lead to reduced glomerular filtration rate and renal failure. There may be modest differences in GI and renal risks with the different agents, but these are minimal. Prophylaxis against gastric ulceration with anti-ulcer drugs has been recommended, and one agent, misoprostol, is approved for use in the United States for this purpose. Whether use of prophylaxis will increase or decrease the costs associated with NSAID therapy remains to be determined. Nonacetylated salicylates may cause less GI adverse effects and may be somewhat "renal sparing." Strategies that would reduce the cost of care for painful musculoskeletal disorders without compromising quality of care include using acetaminophen instead of an NSAID for noninflammatory disorders, trying nonacetylated salicylates as less expensive and safer alternatives to NSAIDs, using one agent at a time, allowing sufficient time to evaluate the therapeutic effect before changing agents, returning to the least expensive and/or safest drug if a trial of several in succession fails to find one that is clearly better, and reserving prophylactic use of antiulcer agents for patients who are at especially high risk and for whom anti-inflammatory effects are clearly needed.

Circulating nitric oxide metabolites during luteolysis and the effect of luteinizing hormone on circulating nitric oxide metabolites in heifers.

Temporal relationships among circulating concentrations of nitric oxide metabolites (NOM), progesterone (P4), and luteinizing hormone (LH) within the hours of a PGFM pulse were studied during luteolysis in heifers. The peak of a PGFM pulse was designated Hour 0. All of the following increases and decreases were significant. Within a spontaneous PGFM pulse (experiment 1; n = 7), concentrations of P4 and LH decreased between Hours -1 and 0 and increased between Hours 0 and 1; NOM increased between Hours -1 and 2. In experiment 2, PGFM pulses were simulated by intrauterine infusion of PGF2α (PGF group, n = 6), and another group was also treated with acyline to inhibit LH secretion (acyline-PGF group, n = 6). Averaged over the two groups, concentration of P4 decreased between Hours -2 and 0, increased (rebounded) between Hours 0 and 1, and decreased after Hour 2. In the PGF group, concentration of LH decreased between Hours -2 and -0.5 and increased between Hour 0 and Hour 1.5 to a maximum at Hour 1.5; NOM decreased between Hours -2 and -1.5 and increased between Hours 0 and 1.5. In the acyline-PGF group, the effect of hour was not significant for concentrations of LH and NOM. The absence of an increase in NOM concentration when LH was inhibited is a novel finding. The hypotheses were supported that concentrations of LH and NOM are temporally related, and LH has a role in the increase in NOM within the hours of a PGFM pulse.

Relationships among nitric oxide metabolites and pulses of a PGF2α metabolite during and after luteolysis in mares.

Hourly circulating concentrations of a PGF2α metabolite (PGFM), progesterone (P4), and LH were obtained from a reported project, and concentrations of nitric oxide (NO) metabolites (NOMs; nitrates and nitrites) were determined in eight mares. Unlike the reported project, hormone concentrations were normalized to the peak of the first PGFM pulse of luteolysis (early luteolysis), second PGFM pulse (late luteolysis), and a pulse after luteolysis. The duration of luteolysis was 23.1 ± 1.0 hours, and the peak of the first and second PGFM pulses occurred 6.5 ± 0.9 and 14.8 ± 0.8 hours after the beginning of luteolysis. Concentration of P4 decreased progressively within and between the PGFM pulses Changes were not detected in LH concentration in association with the PGFM pulses. Concentration of NOMs was greater (P < 0.05) at the peak of the PGFM pulse during early luteolysis (88.8 ± 15.0 µg/mL) than during late luteolysis (58.8 ± 9.0 µg/mL). Concentration of NOMs began to decrease (P < 0.05) 4 hours before the peak of the PGFM pulse of early luteolysis. Concentration began to increase (P < 0.05) an hour after the peak of the PGFM pulse of late luteolysis. An NOM decrease and increase was not detected during the PGFM pulse after luteolysis. On a temporal basis, results indicated that NO either is not required for luteolysis in mares or has a role in or responds only during late luteolysis. A caveat is that the relative contribution of the CL versus other body tissues to circulating concentrations of NOMs in mares has not been determined.

Differences between follicular waves 1 and 2 in patterns of emergence of 2-mm follicles, associated FSH surges, and ovarian vascular perfusion in heifers.

The emergence (first detection) of 2-mm follicles, FSH surges, and ovarian vascular perfusion for follicular wave 1 and surge 1 (n = 26) and wave 2 and surge 2 (n = 25) were studied daily in heifers. The day the future dominant follicle was closest to 5.5 mm was designated Day 0 for each wave. In wave 1, many 2-mm follicles (41%) emerged on Days -5 to -3, whereas FSH surge 1 did not begin until Day -3. Concentration of FSH increased abruptly in 1 day to a peak on the day of maximal number of emerging 2-mm follicles, although the day of maximal number relative to Day 0 differed among individuals. The first emergence of 2-mm follicles in wave 2 occurred concurrently with the first increase in the FSH of surge 2. In wave 1, ovarian resistance to vascular perfusion was negatively correlated (r = -0.48, P < 0.05) with a number of 2-mm follicles on Days -4 to -1 for ovaries that did not contain the preovulatory follicle; vascular perfusion increased with an increase in the number of small follicles. The following hypotheses were supported for wave 1 but not for wave 2: (1) an increase in the number of emerging 2-mm follicles of a follicular wave occurs before the beginning of an increase in FSH, (2) the day of maximal number of emerging 2-mm follicles occurs concurrently with an abrupt FSH increase on different days among individuals, and (3) the association between the number of emerging 2-mm follicles and the extent of ovarian vascular perfusion is positive.

Spontaneous and experimental conversion of a regressing subordinate follicle of wave 1 to the dominant follicle of wave 2 in heifers.

Examination of daily ultrasound records from a previous study indicated that spontaneous conversion of a regressing largest subordinate follicle (SF) of wave 1 (SF1) to the dominant follicle (DF) of wave 2 (DF2) occurred on Day 6 or 7 (Day 0 = ovulation) in two of 28 heifers (7%). A conversion was considered definitive on the basis of no other SFs in the same ovary as SF1, thereby avoiding error in maintaining follicle identity. Spontaneous conversion appeared to involve an FSH fluctuation. In a separate study, experimental conversion of SF1 to DF2 was studied by ultrasonic imaging every 6 hours after ablating follicles other than SF1 when DF of wave 1 was close to 11.0 mm (hour 0). Diameter of SF1 decreased (P < 0.01) between hours -6 (7.8 ± 0.3 mm) and 0 (7.6 ± 0.3 mm). A decrease of 0.1 to 0.8 mm occurred in each heifer, indicating that SF1 was in early regression at hour 0. Conversion occurred in four of 12 (33%) heifers. A diameter increase (P < 0.05) in DF2 after conversion from SF1 occurred between hours 6 and 12. An increase (P < 0.05) in FSH occurred by hour 12 with and without conversion of SF1. Concentration of FSH at each of hours 30 to 48 was greater (P < 0.05) for nonconversion than that for conversion of SF1 to DF2 and greater (P < 0.05) for conversion than that for the basal concentration in controls (n = 7). The hypothesis that a regressing SF1 can be converted to DF2 by ablating other follicles was supported.

A prospective study of proximal femur bone mass following cemented and uncemented hip arthroplasty.

Cross-sectional studies have demonstrated significant decreases in bone mass in femoral cortical bone adjacent to prostheses. Thirty-six patients who had undergone 31 cemented and 9 uncemented primary total hip arthroplasties (THA) were prospectively studied to define further the natural history of this femoral cortical bone loss. Dual-energy X-ray absorptiometry (DXA) was employed to quantify bone mineral density (BMD) changes in four subregions around the femoral prostheses. Femoral BMD loss (average 12.3%) was observed in the three proximal subregions 2 months postoperatively. This loss increased to 21.2% by 6 months postoperatively, and by 2 years postoperatively it averaged 25.5% in the same three subregions. There were no significant BMD changes in the subregion distal to the prosthesis tip or in the contralateral hip. Subgroups were compared based on prosthesis size and cement use. Statistically significant differences in BMD loss were observed between the large cemented cobalt chrome prosthesis group (n = 8) and the large uncemented titanium prosthesis group (n = 8). These differences were only present in the most proximal medial subregion where the large cemented groups had twice the bone loss in this area as compared with the large uncemented group. The data indicate that bone loss occurs adjacent to femoral prosthesis within 2 months of surgery and that DXA is a useful technique to quantify prospectively femoral cortical bone loss following THA.

Sarcoidosis and common variable immunodeficiency. Report of 8 cases and review of the literature.

The true incidence of sarcoidosis in common variable immunodeficiency (CVID) is unknown. We report here 8 cases of sarcoidosis among 80 patients with CVID followed in our clinics, along with 22 well-documented cases reported in the literature. Sarcoidosis, therefore, represents an important entity to consider among patients with CVID who exhibit clinical, radiographic, laboratory, and biopsy findings compatible with sarcoidosis. Conversely, the diagnosis of CVID should be considered in patients with sarcoidosis who do not exhibit the characteristic hypergammaglobulinemia and who have a history of recurrent infections. Although many features of sarcoidosis are similar in patients with CVID to those in patients with sarcoidosis alone, there are many important differences. Patients with CVID in whom sarcoidosis develops present with hypogammaglobulinemia rather than hypergammaglobulinemia and have a higher prevalence of recurrent infections, thrombocytopenia, and splenic involvement. Steroids, in most cases, appeared helpful in reducing adenopathy and splenomegaly, improving uveitis, lowering serum alkaline phosphatase, and reversing hematologic abnormalities. The underlying pathophysiology responsible for the association of these 2 disorders in the same patient remains obscure. However, as more patients are identified, it may be possible to gain a better understanding of the immunologic defect responsible for the dual presentation of these 2 relatively uncommon diseases.

Plasma ascorbic acid concentrations relate inversely to blood pressure in human subjects.

This study relates antioxidant status and blood pressure (BP) in 168 healthy residents of Augusta, GA, following usual diets. BP ranges were systolic (S) 84-152, mean 112 +/- 1 mm Hg, and diastolic (D) 52-96, mean 72 +/- 1 mm Hg. Plasma concentrations of ascorbic acid (AA) were significantly inversely related to SBP (r = -0.18, P < 0.05) and DBP (r = -0.20, P < 0.01); with regression equations SBP vs AA = -0.083C + 116 and DBP = -0.077C + 76. Highest and lowest quintiles of AA differed significantly in mean SBP (108 +/- 2, 113 +/- 2 mm Hg) and DBP (69 +/- 1, 74 +/- 2), P < 0.05. Plasma AA concentrations were significantly lower in the smokers. By deleting smokers, the inverse relations of SBP and DBP with plasma AA and the slopes of the equation were enhanced. Plasma selenium, alpha-tocopherol, alpha-tocopherol:cholesterol ratio, retinol and taurine were not related to BP; whereas male gender, body mass index, body fat distribution, plasma cholesterol, low density lipoprotein cholesterol, and triglycerides correlated.

Creation of a regional medical-nutrition education network.

The Southeastern Regional Medical-Nutrition Education Network (SER-MEN) was developed to coordinate and improve nutrition education in a consortium of the medical schools in Alabama, Florida, Georgia, and South Carolina. SERMEN's central office is at the Medical College of Georgia with the testing office at the University of Alabama at Birmingham. Students, faculty, and consultants in nutrition, education, and computer networking work together on projects on each campus that are coordinated and planned through semiannual meetings. A standardized examination was developed with the Nutrition Test-Item Bank to assess nutrition knowledge at various years of medical students from network schools. Each SERMEN school is connected to a microcomputer system at the central office that provides access to a data base of nutrition education and resources on each campus for developing curricula and syllabi. Funding has been provided by societies, foundations, and government agencies.

Synthesis and structure-activity relationships of new 9-N-alkyl derivatives of 9(S)-erythromycylamine.

A series of new 9-N-alkyl derivatives of 9(S)-erythromycylamine has been synthesized by reductive alkylation of erythromycylamine with aliphatic aldehydes and sodium cyanoborohydride. Alternative syntheses employing hydrogenation methods have also been developed. These new 9-N-alkyl derivatives possess excellent antimicrobial activity in vitro and in vivo, especially when administered orally to treat experimental infections in mice. From structure-activity studies, 9-N-(1-propyl)erythromycylamine (LY281389) was selected as the most efficacious derivative. These methods have also been extended to the synthesis of some 9-N,N-dialkyl derivatives of erythromycylamine.

Recruiting participants for community-based research: the Diabetic Retinopathy Awareness Program.

PURPOSE: Recruiting participants is a major challenge for population studies. We present the recruitment methods followed by the Diabetic Retinopathy Awareness Program (DRAP), a community-based, randomized, masked, controlled trial to meet and exceed its sample size goals. METHODS: A county-wide multi-media promotional campaign to recruit and enroll participants in the trial was planned and executed from October 1993 through April 1994, with the assistance of the local news media and community and professional groups. A toll-free 800 number recruitment line was established, and postage-paid recruitment postcards distributed. The trial was designed to examine whether a mailed educational intervention could increase compliance with vision care guidelines among persons with diabetes in the community. RESULTS: A total of 2308 persons with diabetes were interviewed for eligibility and 813 enrolled in the intervention trial, exceeding the original recruitment goals of 1800 and 600, respectively. Those who completed the enrollment interview reflected county demographics. During recruitment, newspaper, television and radio stories featured the study; pharmacies and physician offices displayed study materials; public service announcements appeared in local print and broadcast media. The largest single recruitment response was a local television news report, followed by a newspaper story. CONCLUSIONS: These experiences substantiate the need for a comprehensive coordinated approach, using planned multiple sources, to achieve recruitment success. By engaging the lay and professional communities along with the media, recruitment costs can be kept to a minimum. Participant costs can be minimized by employing a toll-free number and eliminating study participant travel, thus allowing for inclusion of traditionally underserved populations. This approach is applicable to other studies, where community-based participation is desired.

Intragastric nitrosation of nicotine is not a significant contributor to nitrosamine exposure.

To determine the potential for intragastric nicotine nitrosation, we carried out a kinetic study of the reaction of nicotine with nitrous acid in aqueous solution. The reaction of nicotine with nitrous acid resulted in the formation of three products, NNA, NNN, and NNK. The three parallel reactions were first order of 10-6 L/mol/s. The optimum pH range for formation of NNA, NNN, and NNK was 2.4 to 3.1. Thiocyanate (100 mM) slightly increased the rate of formation of NNN and NNK but tripled the rate of formation of NNA at pH 3.5 at 37 degrees C. We have also studied the nitrosation of pseudooxynicotine, a bacterial and fungal metabolite of nicotine. This secondary amine nitrosated rapidly to produce NNK. Our proposed mechanism for the conversion of nicotine to NNK includes nine kinetically distinct steps and is in agreement with our experimental results. The rate limiting step involves the formation of nicotine-1',2'-iminium ion. This ion hydrolyzes to form pseudooxynicotine which undergoes rapid, irreversible nitrosation to NNK. Given the very slow rate of nicotine nitrosation, it is unlikely that nicotine itself contributes to exposure to nitroso compounds due to chemically mediated intragastric nitrosation.