Four-year follow-up of a prospective trial of HLA and MICA antibodies on kidney graft survival

In 2002, 1329 patients with functioning transplants were prospectively tested for HLA antibodies in the 13th International Histocompatibility Workshop. Four years after testing, deceased donor graft survival among 806 patients not having antibodies in 2002 was 81% compared to 58% for 158 patients with HLA antibodies (p < 0.0001) and 72% for 69 patients with MICA antibodies (p = 0.02). Hazard ratio (HR) using death-censored graft survival from multivariate analysis of HLA antibodies was 3.3 (p < 0.00001) and 2.04 for MICA (p = 0.01). In the 14th Workshop, at 1 year follow-up, survival for 1319 patients receiving deceased donor grafts and no HLA antibodies was 96% compared to 94% for 344 patients with HLA antibodies (p = 0.0004) and 83% survival for 33 patients with MICA (p = 0.0005). HR from multivariate analysis: HLA antibodies was 3.6 (p < 0.00001) and 6.1 for MICA (p = 0.006). Twelve patients with donor specific antibodies tested by single antigen beads had a 1 year survival of 64% (p = 0.008), and 27 patients with non-donor specific 'strong' antibodies had a 66% survival (p = 0.0003) compared to 92% survival in those with no antibodies. In conclusion, these two prospective trials, after 1 and 4 years, provided strong evidence that HLA and MICA antibodies are associated with graft failure.

Homocysteine metabolism, hyperhomocysteinaemia and vascular disease: an overview

Hyperhomocysteinaemia has been regarded as a new modifiable risk factor for atherosclerosis and vascular disease. Homocysteine is a branch-point intermediate of methionine metabolism, which can be further metabolised via two alternative pathways: degraded irreversibly through the transsulphuration pathway or remethylated to methionine by the remethylation pathway. Both pathways are B-vitamin-dependent. Plasma homocysteine concentrations are determined by nongenetic and genetic factors. The metabolism of homocysteine, the role of B vitamins and the contribution of nongenetic and genetic determinants of homocysteine concentrations are reviewed. The mechanisms whereby homocysteine causes endothelial damage and vascular disease are not fully understood. Recently, a link has been postulated between homocysteine, or its intermediates, and an alterated DNA methylation pattern. The involvement of epigenetic mechanisms in the context of homocysteine and atherosclerosis, due to inhibition of transmethylation reactions, is briefly overviewed.

Synthesis of leptin in human placenta

Gender-based differences in serum leptin levels have been reported in umbilical cord blood, and leptin has been detectedin human amniotic fluid. In order to understand if leptin may be directly synthesized by human placentae an analysis made up of several steps was performed. First at all RT-PCR analysis from placenta-derived RNA was used to detect human leptin mRNA. The leptin-like immunoradioactivity detected in placentae extracts was identical to human leptin according to the criteria of charge, immunorecognition, SDS-PAGE analysis and blotting, indicating that intact leptin was found and no variants in size, charge or immunoactivity were present in the placentae. Finally an immunohistochemical analysis showed the presence of leptin in the cytoplasm of syncytiotrophoblast cells but not in the core of villi.

IN CONCLUSION

leptin is synthesized as a single molecular variant identical to human recombinant leptin in human placentae at delivery.

Is there evidence of a relationship between benign prostatic hyperplasia and prostate cancer? Findings of a literature review

CONTEXT

More than half the male population aged >50 yr have histologic evidence of benign prostatic hyperplasia (BPH), while prostate cancer (PCa) is among the most common male cancers according to recent registry data. Understanding the aetiologies of both conditions is crucial to reduce the resulting burden of mortality and morbidity.

OBJECTIVE

This review aims to examine the available data on the epidemiology, pathology, risk factors, and genetic markers involved in BPH and PCa; to discuss their clinical implications for management of both conditions; and to discuss their implications for PCa prevention. Our primary objective was to clarify the relationship between BPH and PCa by bringing together evidence from diverse areas of research.

EVIDENCE ACQUISITION

The primary source of data was PubMed, which was searched using Boolean strategies and by scanning lists of related articles. We also examined secondary sources from reference lists of retrieved articles and data presented at recent congresses.

EVIDENCE SYNTHESIS

Accumulating evidence suggests that BPH and PCa share important anatomic, pathologic, and genetic links in addition to the well-established epidemiologic association between these conditions. We also found data that suggest interactions between apparently diverse factors, such as dihydrotestosterone levels and inflammation. Recent publications support the hypothesis that both BPH and PCa are part of the metabolic syndrome, while inflammation is emerging as a major contributor to the development of both BPH and PCa. Although many of the findings are preliminary and require further research, they offer new insight into the mechanisms of disease underlying the development of BPH and PCa.

CONCLUSIONS

Available data suggest that epidemiologic and pathologic links exist between BPH and PCa. Evidence of links between the conditions and contributory factors may offer common preventative strategies for BPH and PCa and common therapeutic approaches to their management.

Humoral and cellular responses to cow milk proteins in patients with milk-induced IgE-mediated and non-IgE-mediated disorders

BACKGROUND

Cow milk allergy (CMA) is one of the most common food allergies in childhood. Patients with CMA present with a wide range of immunoglobulin (Ig)E- and non-IgE-mediated clinical syndromes. Limited information is known about the specific humoral and cellular responses to cow milk proteins in these various forms of CMA.

OBJECTIVE

The aim of the study was to determine IgE, IgA, IgG1 and IgG4 antibody levels and lymphocyte proliferative responses to the major cow milk allergens in patients with IgE- and non-IgE-mediated CMA.

METHODS

One hundred and forty cow milk allergic patients, 6 months to 22 years of age, were included in the study. One hundred and thirteen patients had IgE-mediated CMA, 11 had milk protein-induced enterocolitis syndrome and 16 had allergic eosinophilic gastroenteritis. Twenty-one patients without food allergy, 8 months to 18 years of age, served as controls. Serum IgE, IgA, IgG1 and IgG4 antibodies to alpha-, beta-, and kappa-casein, alpha-lactalbumin and beta-lactoglobulin were measured using enzyme-linked immunosorbent assays. For a subset of these patients, we performed lymphocyte proliferation assays to the various milk allergens.

RESULTS

Patients with IgE-mediated CMA had higher specific IgE concentrations to casein compared with whey proteins (P < 0.001). In this group of patients, there was a positive correlation between IgE levels and levels of the other isotypes for all four milk proteins (P < 0.001). In general, the caseins were the more allergenic and antigenic proteins in all groups of patients. Patients with enterocolitis syndrome produced less milk protein-specific IgG4 (P < 0.05) and had a trend for higher IgA antibody levels when compared to the control group. Lymphocyte proliferative responses in all groups with CMA were significantly higher than controls (P < 0.05), although this response was similar in patients with IgE- and non-IgE-mediated CMA.

CONCLUSION

There is a distinct pattern of humoral antibody response in the different forms of CMA. Patients with IgE-mediated CMA have an elevated polyisotypic response to cow milk protein. The relative lack of specific IgG4 production in patients with enterocolitis syndrome may be involved in the pathogenesis of the disease. In general, caseins appear to be the predominant allergen in patients with CMA.

Seismicity Remotely Triggered by the Magnitude 7.3 Landers, California, Earthquake

The magnitude 7.3 Landers earthquake of 28 June 1992 triggered a remarkably sudden and widespread increase in earthquake activity across much of the western United States. The triggered earthquakes, which occurred at distances up to 1250 kilometers (17 source dimensions) from the Landers mainshock, were confined to areas of persistent seismicity and strike-slip to normal faulting. Many of the triggered areas also are sites of geothermal and recent volcanic activity. Static stress changes calculated for elastic models of the earthquake appear to be too small to have caused the triggering. The most promising explanations involve nonlinear interactions between large dynamic strains accompanying seismic waves from the mainshock and crustal fluids (perhaps including crustal magma).

Cognitive sequelae of treatment in childhood acute lymphoblastic leukemia: cranial radiation requires an accomplice

PURPOSE

We evaluated cognitive sequelae of treatment for childhood acute lymphoblastic leukemia (ALL). CNS therapy consisted of cranial irradiation (CRT) or no radiation. Children were also randomized to single intravenous high-dose methotrexate (HD-MTX) or conventional-dose methotrexate (CD-MTX) during induction, and all patients received intrathecal (IT) and systemic continuation chemotherapy.

PATIENTS AND METHODS

Sixty-six patients treated for ALL on Dana-Farber Cancer Institute protocol 87-01 were evaluated by standardized cognitive and achievement tests. These children had been assigned at diagnosis to a standard-risk (SR) or high-risk (HR) group and received no CRT or 18 Gy CRT, respectively. All patients were randomized to receive MTX during remission induction, either as CD-MTX (40 mg/m2) or HD-MTX (4 g/m2) with leucovorin rescue.

RESULTS

There was no difference in cognitive outcomes between radiated and unirradiated patients (P > .4). However, the HD-MTX/CRT combination was associated with decreased intelligence quotient (IQ estimate, 9.3 points) for girls only (P < .08). A specific deficit in verbal coding and memory was documented for all patients (P < .0001).

CONCLUSION

We conclude the following: (1) 18 Gy CRT per se was not an independent toxic agent for cognitive outcome; (2) HD-MTX during induction was associated with IQ decline in girls, but only when it was followed by CRT; and (3) impairment of verbal memory and coding was a consistent finding that was independent of CRT, which implicates some component of chemotherapy, possibly prednisone, as a CNS toxin.

Self-care strategies for symptom management in patients with chronic heart failure

BACKGROUND

The troublesome symptoms experienced by patients with chronic heart failure are associated with diminished quality of life, frequent hospitalizations, and mortality.

OBJECTIVES

To describe the symptoms experienced by patients with heart failure, to detail the self-care strategies used by these patients in managing their symptoms, and to categorize the self-care strategies.

METHODS

Six focus groups were used with 23 patients who had heart failure, along with six focus groups with 18 family members of the patients. Data analysis was performed by transcription of audiotape recordings of the group sessions and review of field notes.

RESULTS

The patients reported a large number of troublesome symptoms, many consistent with past empirical findings, but some not reported in previous studies. Self-care strategies to manage the symptoms clustered into 11 categories.

CONCLUSIONS

Results from this study provided direction for future studies to (a) identify the prevalence, severity, and etiologies of the commonly reported symptoms, particularly cognitive impairment, loss of balance, and depression; (b) evaluate the emotions reported by women with heart failure; and (c) test the strategies as part of an intervention program to improve symptom management in patients with heart failure.

The Placebo Effect in the Pharmacologic Treatment of Patients with Lower Urinary Tract Symptoms

OBJECTIVES

We reviewed placebo responses in randomised controlled trials (RCTs) for pharmacologic treatment of lower urinary tract symptoms (LUTS), including urinary incontinence (UI), overactive bladder, and benign prostatic hyperplasia. Review papers on placebo effects in non-urologic disorders were assessed to compare the magnitude of placebo responses in drugs for LUTS with those reported for other diseases.

METHODS

Data were retrieved from registration trials for LUTS drugs on the Web sites of the Food and Drugs Administration and the European Medicines Agency. Reviews were retrieved from Medline using the MeSH term "placebo effect" (English language; published between 1990 and 2005).

RESULTS

Placebo treatment of LUTS yields reductions in incontinence episodes (IEs) ranging from 32% to 65%, whereas prostate or UI symptom scores are reduced by 9-34%. Genuine drugs decrease IEs by 45-77% and symptom scores by 22-45%. Placebo responses are much lower when objective changes in voided volume or peak flow rate are assessed.

CONCLUSIONS

The placebo effect in LUTS has a strong behavioural component as patients become aware of their voiding habits and potential risk factors. Symptom severity, treatment naivety, study duration, and interaction with health care providers may also influence it. Proper patient selection, study duration, and objective and subjective outcome measures may better separate genuine treatment effects from artefacts. Observational studies with patients representative for real-life situations and covering a sufficient period of time could allow for better understanding of RCT results and their applicability in clinical practice.

Prevalence of hepatitis viruses in an anti-human immunodeficiency virus-positive population from Argentina. A multicentre study

The objectives of this study were to investigate the prevalence of infections with hepatotrophic viruses in an anti-human immunodeficiency virus (HIV)-positive population from Buenos Aires and to compare it among the main risk groups for HIV infection. Four hundred and eighty-four consecutive patients attending the HIV outpatients clinic were studied: 359 men and 125 women, median age 29 years (range 16-67 years); 35.5% had presented acquired immune deficiency syndrome (AIDS)-defining conditions. Two hundred and thirty-four patients were intravenous drug users (IVDU), 99 had homosexual and 142 heterosexual preference, seven had received blood transfusions and two had no risk factors. Hepatitis B surface antigen (HBsAg), and antibodies to hepatitis B core antigen (HBcAb) and to hepatitis C virus (anti-HCV) were investigated in all patients; antibodies to HBsAg (HBsAb) and IgG antibodies to hepatitis D virus (anti-HDV) in all HBcAb-positive patients; hepatitis B e antigen and antibodies to HBeAg (HBeAg) in all HBsAg-positive patients; IgG antibodies to hepatitis A virus (anti-HAV) in the first 307 patients; and IgG antibodies to hepatitis E virus (anti-HEV) in the first 91 patients. As control groups, contemporary voluntary blood donors were studied for prevalence of HAV, HBV, HCV and HEV. The percentages of HBcAb, HBsAg, anti-HCV and anti-HEV (58.5, 14.5, 58.5 and 6.6%, respectively) were significantly higher in anti-HIV-positive patients than in control groups (3.2, 0.5, 1.0 and 1.8%, respectively) (P = 0.000). The prevalence of HBcAb was significantly higher in IVDU (72.6%) than in heterosexuals (33.8%) (P = 0.0001) and in homosexuals (59.6%) (P = 0.0189). The percentage of HBsAg was significantly higher in IVDU (19.2%) than in heterosexuals (6.3%) (P = 0.0004). Anti-HCV was significantly higher in IVDU (92.3%) than in homosexuals (14.1%) and in heterosexuals (33.1%) (P = 0.000 in both cases). The prevalence of anti-HDV was relatively low (1.9%). There was no difference in the percentage of anti-HAV between HIV-positive and negative subjects. In conclusion, there is a high prevalence of HBV and HCV infections in HIV-positive patients from our area. Drug use is the main route of transmission, but prevalence of HCV in patients with, probably, sexually acquired HIV infection is also higher than in the control group. The increased prevalence of HEV infection in HIV-positive individuals is another provocative finding that warrants further study.

Patient characteristics associated with quality of life in European women seeking treatment for urinary incontinence: results from PURE

OBJECTIVE

To investigate the association between patient characteristics and disease-specific and generic quality of life (QOL) as well as the degree of bother in women seeking treatment for urinary incontinence (UI).

METHODS

The Prospective Urinary Incontinence Research (PURE) was a 6-mo observational study with 1055 physicians from 15 European countries enrolling 9487 women. QOL was assessed at the enrolment visit using the urinary Incontinence Quality of Life questionnaire (I-QOL) and the generic EQ-5D. A single-item instrument was used to measure the degree of bother. UI severity was assessed using the Sandvik Index. UI was categorised into stress (SUI), mixed (MUI), and urge (UUI) urinary incontinence by a patient-administered instrument (Stress and Urge Incontinence Questionnaire [S/UIQ]). Multivariate linear (I-QOL, EQ-5D Visual Analogue Scale) and logistic (bother, EQ-5D health state index) regressions were performed.

RESULTS

Mean total I-QOL scores were significantly and independently associated with UI severity, nocturia, age, UI subtype, number of selected concomitant medical conditions, length of suffering from UI before contacting a doctor, smoking status, ongoing use of UI medication, and country. After adjusting for all the covariates, the total I-QOL scores for SUI, MUI, and UUI were 62.7, 53.8 and 60.1, respectively. As with I-QOL, UI severity was also the most important predictor for bother. The number of concomitant medical conditions, together with UI severity, was the variable most strongly associated with EQ-5D.

CONCLUSION

In addition to the UI subtypes, severity of UI should be given more importance in treatment algorithms and in treatment decision-making by both the patient and the physician.

Benign prostatic hyperplasia as a progressive disease: a guide to the risk factors and options for medical management

Benign prostatic hyperplasia (BPH) is a complex disease that is progressive in many men. BPH is commonly associated with bothersome lower urinary tract symptoms; progressive disease can also result in complications such as acute urinary retention (AUR) and BPH-related surgery. It is therefore important to identify men at increased risk of BPH progression to optimise therapy. Several factors are associated with progression, including age and prostate volume (PV). Serum prostate-specific antigen level is closely correlated with PV, making it useful for determining the risk of BPH progression. Medical therapy is the most frequently used treatment for BPH. 5-alpha-reductase inhibitors impact the underlying disease and decrease PV; this results in improved symptoms, urinary flow and quality of life, and a reduced risk of AUR and BPH-related surgery. Alpha-blockers achieve rapid symptom relief but do not reduce the overall risk of AUR or BPH-related surgery, presumably because they have no effect on PV. Combination therapy provides greater and more durable benefits than either monotherapy and is a recommended option in treatment guidelines. The Combination of Avodart and Tamsulosin (CombAT) study is currently evaluating the combination of dutasteride with tamsulosin over 4 years in a population of men at increased risk of BPH progression. A preplanned 2-year analysis has shown sustained symptom improvement with combination therapy, significantly greater than with either monotherapy. CombAT is also the first study to show benefit in improving BPH symptoms for combination therapy over the alpha-blocker, tamsulosin, from 9 months of treatment.

Determination of quaternary ammonium pesticides by liquid chromatography–electrospray tandem mass spectrometry

A method for the direct determination of paraquat, diquat, chlormequat and difenzoquat in water samples, using an on-line solid-phase extraction-liquid chromatography-tandem mass spectrometry system was developed. No sample preparation was required and the detection limits were below the European Union maximum residue levels. The chromatographic separation was performed using an XTera MS C8 column. The concentration of the ion pair reagent, the pH and the gradient elution were optimized to give high recoveries and good chromatographic resolution between quats. The detection was carried out using an ion trap as mass analyzer. Parameters such as the magnitude and duration of the resonant excitation voltage and the magnitude of the trapping RF voltage for full scan tandem mass spectrometry (MS-MS) experiments were studied to establish the optimal experimental conditions. Moreover, the accurate optimization of these parameters allowed MS-MS experiments of low mass ions, below m/z 200, providing unambiguous peak identification. Finally, the reproducibility of the proposed method was shown by good run-to-run and day-to-day precision values and its applicability to the determination of quats in drinking water was evaluated using spiked samples.

5,10-Methylenetetrahydrofolate reductase 677C-->T and 1298A-->C mutations are genetic determinants of elevated homocysteine

BACKGROUND

Methylenetetrahydrofolate reductase (MTHFR) is one of the main regulatory enzymes of homocysteine metabolism. Elevated plasma total homocysteine (tHcy) is a major risk for cardiovascular disease. A common 677C-->T mutation in the MTHFR gene results in decreased enzymic activity, and contributes to increased plasma tHcy, in association with low plasma folate. A recently described 1298A-->C mutation in the MTHFR gene clearly reduces MTHFR activity (although to a lesser extent than the 677C-->T) but its effect on plasma tHcy levels is not yet clear.

AIM

To investigate the frequency of these two MTHFR polymorphisms in a Portuguese population, and to correlate the MTHFR genotype with the biochemical phenotype at the level of homocysteine and folate concentrations.

DESIGN

Prospective population survey.

METHODS

We studied 117 healthy volunteers (71 females, 46 males). The 677C-->T and 1298A-->C mutations were screened by PCR-RFLP. Levels of plasma tHcy and folate, and red blood cell folate, were determined.

RESULTS

The allele frequencies of the 677C-->T and 1298A-->C mutations were 0.33 and 0.28, respectively. Homozygotes for the 677C-->T mutation had significantly elevated plasma tHcy and RBC folate levels and significantly lowered plasma folate concentrations than subjects without the mutation. The 1298A-->C mutation showed a significant effect on plasma tHcy, but not on plasma folate or RBC folate levels.

DISCUSSION

The observed 677T allele frequency is not consistent with the idea of a north-south gradient as previously suggested. The 1298A-->C mutation is common in Portugal. Both MTHFR mutations showed effects on plasma tHcy levels.

Increased or decreased locomotor response in rats following repeated administration of apomorphine depends on dosage interval

Administration of drugs that reduce the influence of dopamine at its receptor site can lead to postsynaptic supersensitivity, whereas treatment with dopamine (DA) agonists can cause postsynaptic subsensitivity. Both unaltered and enhanced postsynaptic responses to DA have been shown after pretreatment with DA agonists. In the present manuscript pretreatment with apomorphine, a dopaminergic agonist, is shown to induce either increased or reduced locomotor activity. When a drug-free period between successive injections was allowed, apomorphine induced an enhanced locomotor response, whereas a reduced response occurred when each dose was injected before the previous apomorphine dose had been completely metabolized. Pretreatment with both high (1 and 3 mg/kg) and low (0.05 mg/kg) apomorphine doses enhanced the response. Apomorphine treatment that caused enhanced locomotor responses did not modify the stereotypy response to the drug. Similar enhanced or reduced response were found in rats with partial lesions of the nigrostriatal system. These altered responses to DA agonists may have important clinical consequences. The present data also suggest the existence of a different DA systems for locomotor and stereotypy actions of dopaminergic agonists.

T cell diversity and TcR repertoires in teleost fish

In vertebrates, the diverse and extended range of antigenic motifs is matched to large populations of lymphocytes. The concept of immune repertoire was proposed to describe this diversity of lymphocyte receptors--IG and TR--required for the recognition specificity. Immune repertoires have become useful tools to describe lymphocyte and receptor populations during the immune system development and in pathological situations. In teleosts, the presence of conventional T cells was first proposed to explain graft rejection and optimized specific antibody production. The discovery of TR genes definitely established the reality of conventional T cells in fish. The development of genomic and EST databases recently led to the description of several key T cell markers including CD4, CD8, CD3, CD28, CTLA4, as well as important cytokines, suggesting the existence of different T helper (Th) subtypes, similar to the mammalian Th1, Th2 and Th17. Over the last decade, repertoire studies have demonstrated that both public and private responses occur in fish as they do in mammals, and in vitro specific cytotoxicity assays have been established. While such typical features of T cells are similar in both fish and mammals, the structure of particular repertoires such as the one of gut intra-epithelial lymphocytes seems to be very different. Future studies will further reveal the particular characteristics of teleost T cell repertoires and adaptive responses.

Ion-pair liquid chromatography--atmospheric pressure ionization mass spectrometry for the determination of quaternary ammonium herbicides

High-performance liquid chromatography coupled with atmospheric pressure ionization mass spectrometry (electrospray and atmospheric pressure chemical ionization) has been used to characterize some quaternary ammonium herbicides (quats). The separation of these compounds was carried out using ion-pair chromatography with heptafluorobutyric acid (15 mM, pH 3.3) and acetonitrile gradient elution for successful coupling to mass spectrometry. Detection limits down to 0.1-4 micrograms l-1 were obtained for spiked tap water following a preconcentration step. Good reproducibilities (day-to-day and run-to-run) were also obtained.

Morbid obesity, hypertensive disease and the renin-angiotensin-aldosterone axis

BACKGROUND

Resistance to insulin and secondary hyperinsulinemia seem to be the putative link between morbid obesity (MO) and hypertensive disease (HD). Adipose tissue can secrete leptin and angiotensinogen, among other substances. Leptin activates the sympathetic nervous system, leading to HD. Angiotensinogen is a substrate for renin, therefore taking part in the renin-angiotensin-aldosterone axis and the regulation of blood pressure. In MO, both hypertrophy and hyperplasia of the adipocytes lead to an increase in the secretion of both substances, leading to loss of the equilibrium between the levels of both hormones. The aim of the present study was to evaluate these abnormalities and their potential reversibility following bariatric surgery.

METHODS

Data from 100 patients with MO was retrospectively evaluated. Anthropometric data, the plasma renin activity (PRA), plasma levels of aldosterone, ACE, potassium and sodium were collected both prior to surgery and 6, 12, 24 and 36 months after surgery.

RESULTS

The waist-hip ratio (WHR) before surgery allowed classification of our patients in two groups: central obesity (WHR > or =0.90 in men and > or =0.85 in women); peripheral obesity (WHR <0.90 in men and <0.85 in women). In patients with central obesity, high levels of PRA, aldosterone and ACE with sodium retention and potassium loss and high insulin levels, were found. These changes were not found in patients with peripheral obesity. After gastric bypass, these abnormalities tended to disappear, mainly in the first 6 months.

CONCLUSIONS

The reduction of BMI and WHR after gastric bypass confirmed this operation to be effective against MO. The high basal levels of insulin and the high rate of HD and diabetes in patients with central obesity seem to indicate that they suffer a metabolic syndrome with significant hormonal imbalances and sodium retention. Patients with peripheral obesity only showed a peripheral resistance against insulin, probably with a shorter duration of the hormonal action, but they did not show hormonal abnormalities or sodium retention. After gastric bypass these abnormal hormone levels tended to normalize.

Prevention of post-transfusion non-A, non-B hepatitis by non-specific immunoglobulin in heart surgery patients

To evaluate the effectiveness of immune serum globulin (ISG) in preventing non-A, non-B hepatitis, 291 heart surgery patients who received blood from voluntary donors were randomly assigned to receive either ISG or no additional protection. ISG was given intramuscularly before and 1 week after transfusion. 98 controls and 100 in the ISG group completed the study. Post-transfusion non-A, non-B hepatitis developed in 11 (11.2%) controls but in only 3 (3.0%) of the ISG group (p = 0.0203). 8 (72.7%) of control group with hepatitis had symptoms, and in 5 (45.4%) the disease became chronic. The disease was self-limiting in all 3 ISG patients affected, and only 1 of them had symptoms. Among those with non-A, non-B hepatitis aminotransferase levels were higher in the controls than in the ISG patients. Incubation periods longer than 8 weeks correlated with a tendency for the disease to become chronic. ISG recipients had shorter as well as more homogeneous incubation periods. ISG could be a safe, low-cost means for preventing post-transfusion non-A, non-B hepatitis which does not call for the discarding of donated blood.

Cancer in banana plantation workers in Costa Rica

BACKGROUND

Costa Rica has population and disease registries with potential value for epidemiological research. Pesticides have been intensively used on banana plantations, for example dibromochloropropane (DBCP). This study was planned to examine the quality of the cancer and civil registries and the feasibility of record linkages, and to explore cancer patterns among a highly exposed group.

METHODS

A retrospective cohort study was carried out. Workers on the payrolls of banana companies, as reported to the Social Security System at any time between 1972 and 1979, were followed up in the cancer registry between 1981 and 1992: 29 565 men and 4892 women for 407 468 person-years. The observed cases of cancer were compared to the expected values, derived from the national incidence rates.

RESULTS

We identified 368 cancer cases, 292 among men (standardized incidence ratio [SIR] = 76, 95% confidence interval [CI] 67-84) and 76 among women (SIR = 116, 95% CI: 90-142). Among men increased SIR were observed for melanoma (SIR = 197, 95% CI: 94-362) and penile cancer (SIR = 149, 95% CI: 55-324); among women for cervix cancer (SIR = 182, 95% CI: 122-241) and leukaemia (SIR = 274, 95% CI: 86-639). Risk estimates for lung cancer were evaluated among male workers with the longest time of employment.

CONCLUSIONS

Follow-up was difficult due to deficient identification variables in the cancer registry and to easier identification of the living compared to the decreased in the civil registry at the end of the observation period. The various systematic errors in this study are likely to produce an underestimation of the relative risk estimates. This study contributes to improvements of the registries and increases the potential for cancer epidemiology in Costa Rica and other developing countries.

Genetic variants in transcription factors are associated with the pharmacokinetics and pharmacodynamics of metformin

One-third of type 2 diabetes patients do not respond to metformin. Genetic variants in metformin transporters have been extensively studied as a likely contributor to this high failure rate. Here, we investigate, for the first time, the effect of genetic variants in transcription factors on metformin pharmacokinetics (PK) and response. Overall, 546 patients and healthy volunteers contributed their genome-wide, pharmacokinetic (235 subjects), and HbA1c data (440 patients) for this analysis. Five variants in specificity protein 1 (SP1), a transcription factor that modulates the expression of metformin transporters, were associated with changes in treatment HbA1c (P < 0.01) and metformin secretory clearance (P < 0.05). Population pharmacokinetic modeling further confirmed a 24% reduction in apparent clearance in homozygous carriers of one such variant, rs784888. Genetic variants in other transcription factors, peroxisome proliferator-activated receptor-α and hepatocyte nuclear factor 4-α, were significantly associated with HbA1c change only. Overall, our study highlights the importance of genetic variants in transcription factors as modulators of metformin PK and response.