The Gothenburg Breast Screening Trial

BACKGROUND: Although there is evidence for a reduction in breast carcinoma mortality with mammographic screening, some doubts have been expressed, and there is still uncertainty regarding the age specific effects. METHODS: The authors report on a randomized, controlled trial of mammographic screening for breast carcinoma that was conducted among 51,611 women (21,650 women who were invited to a screening [the study group] and 29,961 women in a control group) ages 39-59 years in Gothenburg, Sweden. Among women in the study group, the screening interval was 18 months. The screening phase of the trial took place in 1982-1991, and follow-up for breast carcinoma mortality continued until December 31, 1996. Mortality from breast carcinoma was analyzed using a Poisson regression model. Overall and age specific effects of invitation to mammography screening on breast carcinoma mortality were calculated. Three mortality effects were estimated: the effect on deaths from breast tumors diagnosed during the screening phase of the trial, as assessed by an independent Endpoint Committee (the EPC evaluation model); the effect on deaths from breast carcinoma diagnosed during the screening phase of the trial, as determined by data from the National Cancer Registry and the National Cause of Death Register (the SCB evaluation model); and the effect on deaths from all breast carcinomas diagnosed up to December 31, 1996, as determined by the National Cancer Registry and the National Cause of Death Register (the SCB follow-up model). RESULTS: A nonsignificant, 21% reduction in the rate of mortality from breast carcinoma with invitation to screening was observed using the EPC evaluation model (relative risk [RR], 0.79; 95% confidence interval [95% CI], 0.58-1.08; P = 0.14); and a borderline significant, 23% rate reduction was observed using the SCB follow-up model (RR, 0.77; 95% CI, 0.60-1.00; P = 0.05). Age specific analyses yielded greater mortality rate reductions for the groups of women ages 39-44 years, 45-49 years, and 55-59 years, but there was no mortality rate reduction in the group of women ages 50-54 years. The effects of invitation to mammographic screening on the incidence of lymph node-positive disease closely paralleled the effects of invitation on breast carcinoma mortality. The effect on breast carcinoma mortality was consistent with the effect on all-cause mortality, suggesting no bias in classification of cause of death. Breast carcinoma incidence in the study group was almost identical to the incidence in the control group after trial by screening had ended in the control group (RR, 0.98; 95% CI, 0.88-1.09; P = 0.7). CONCLUSIONS: The current results support the commonly observed 20-30% reduction in breast carcinoma mortality with invitation to screening. The impression that screening is less effective in women younger than 50 years may be an oversimplification. Age specific effects should be a target for further research.     

Chlamydia1 antibodies in women who suffer miscarriage

Objective To ascertain the relation between previous chlamydial infection and miscarriage.
Design A prospective study of 349 women who had a miscarriage.
Participants Women surgically treated for spontaneous pregnancy loss on an outpatient basis at a hospital.
Subjects Three hundred and forty-nine women who miscarried, of whom 91 had at least one previous miscarriage and 33 had had two or more miscarriages previously. Age-matched women who had a normal pregnancy served as controls.
Interventions Blood samples were drawn from patients and controls for antibody determination.
Main outcome measures Patients and controls were compared regarding the frequency of Chlamydia trachomatis IgG antibodies (titre 2 1/32). Antibodies to C. pneumoniae were also analysed to study cross reactivity.
Results The frequency of IgG antibodies among the patients was 137/349 (39.3%) which was not statistically different from that among controls (116/349; 33.2%). Even among those who had miscarried previously the antibody frequencies did not differ significantly between patients and controls. The rate of C. trachomatis antibodies was about the same whether or not antibodies to C. pneumoniae were present in both patients and controls.
Conclusion No association was found serologically between previous chlamydial infection and miscarriage and no significant cross reactivity between C. pneumoniae and C. trachomatis could be detected.     

Purification and immunochemical analysis of histidine decarboxylase from murine mastocytoma

Application of a new scheme of purification for histidine decarboxylase (E.C. 4.1.1.22) leads to a highly purified enzyme (5000 nmol/mg·h, i.p. 5.0, M.W.: 110 kD) with reasonable stability (rest activity 80% after 3 weeks at 6–8°C). A major protein contaminant seen on electrofocusing (i.p. 4.6) shows immunological identity with the enzyme-containing protein (i.p. 5.0) and might be involved in the aggregation of the enzyme.     

Injection of embryonic stem cells into scarred rabbit vocal folds enhances healing and improves viscoelasticity: short-term results

OBJECTIVES: Scarring caused by trauma, postcancer treatment, or inflammation in the vocal folds is associated with stiffness of the lamina propria and results in severe voice problems. Currently there is no effective treatment. Human embryonic stem cells (hESC) have been recognized as providing a potential resource for cell transplantations, but in the undifferentiated state, they are generally not considered for therapeutic use due to risk of inadvertent development. This study assesses the functional potential of hESC to prevent or diminish scarring and improve viscoelasticity following grafting into scarred rabbit vocal folds. STUDY DESIGN: hESC were injected into 22 scarred vocal folds of New Zealand rabbits. After 1 month, the vocal folds were dissected and analyzed for persistence of hESC by fluorescence in situ hybridization using a human specific probe, and for differentiation by evaluation in hematoxylin-eosin-stained tissues. Parallel-plate rheometry was used to evaluate the functional effects, i.e., viscoelastic properties, after treatment with hESC. RESULTS: The results revealed significantly improved viscoelasticity in the hESC-treated vs. non-treated vocal folds. An average of 5.1% engraftment of human cells was found 1 month after hESC injection. In the hESC-injected folds, development compatible with cartilage, muscle and epithelia in close proximity or inter-mixed with the appropriate native rabbit tissue was detected in combination with less scarring and improved viscoelasticity. CONCLUSIONS: The histology and location of the surviving hESC-derived cells strongly indicate that the functional improvement was caused by the injected cells, which were regenerating scarred tissue. The findings point toward a strong impact from the host microenvironment, resulting in a regional specific in vivo hESC differentiation and regeneration of three types of tissue in scarred vocal folds of adult rabbits.     

Factors influencing the regulation of cytokine balance during islet transplantation in mice

Many experimental islet studies compare the effect of allogeneic transplantations with either syngeneically transplanted or sham-operated animals. Presently we examined multiple "control" treatments to be able to distinguish effects by the operating procedures themselves versus reactions induced by islet graft rejection. Herein, we have studied untreated, sham-operated, syngeneically or allogeneically (C57BL/6) islet transplanted BALB/c mice, and subsequently examined cytokine production (TNFalpha, IFNgamma, IL-4, IL-10, IL-17 and TGF-beta) in vitro by RT-PCR and ELISA in spleen cells and transplants. To investigate if the strain of the recipient mice influences cytokine production we also performed allogeneic islet transplantations in the reverse direction. So-called control treatments such as sham operations and syngeneic transplantations had a distinct effect on cytokines in spleen cells, possibly induced by surgery and/or anaesthesia. This seems to decrease the regulatory T cells, thereby leading to increased cytokine expression. Furthermore, spleen cells from surgically manipulated animals seem to have a decreased responsive capacity to con A stimulation in culture. Cytokine generation, FoxP3 mRNA expression and COX-2 mRNA expression in the two investigated mouse strains were sometimes altered in opposite directions by the treatments. In conclusion, the genetic background of both the islet donor and recipient has a major impact on both the magnitude and skewing of a cytokine response. Moreover, factors not directly related to allorejection influences systemic cytokine production in connection to islet transplantation.     

Safety, efficacy, and biomarker findings of PBT2 in targeting Abeta as a modifying therapy for Alzheimer's disease: a phase IIa, double-blind, randomised, placebo-controlled trial

BACKGROUND: PBT2 is a metal-protein attenuating compound (MPAC) that affects the Cu2(+)-mediated and Zn2(+)-mediated toxic oligomerisation of Abeta seen in Alzheimer's disease (AD). Strong preclinical efficacy data and the completion of early, clinical safety studies have preceded this phase IIa study, the aim of which was to assess the effects of PBT2 on safety, efficacy, and biomarkers of AD. METHODS: Between December 6, 2006, and September 21, 2007, community-dwelling patients over age 55 years were recruited to this 12-week, double-blind, randomised trial of PBT2. Patients were randomly allocated to receive 50 mg PBT2, 250 mg PBT2, or placebo. Inclusion criteria were early AD (mini-mental state examination [MMSE] score between 20 and 26 points or Alzheimer's disease assessment scale-cognitive subscale (ADAS-cog) score between 10 and 25 points), taking a stable dose of acetylcholinesterase inhibitor (donepezil, galantamine, or rivastigmine) for at least 4 months, a modified Hachinski score of 4 points or less, and CT or MRI results that were consistent with AD. The principal outcomes were safety and tolerability. Secondary outcomes were plasma and CSF biomarkers and cognition. Analysis was intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00471211. FINDINGS: 78 patients were randomly assigned (29 to placebo, 20 to PBT2 50 mg, and 29 to PBT2 250 mg) and 74 (95%) completed the study. 42 (54%) patients had at least one treatment emergent adverse event (10 [50%] on PBT2 50 mg, 18 [62%] on PBT2 250 mg, and 14 [48%] on placebo). No serious adverse events were reported by patients on PBT2. Patients treated with PBT2 250 mg had a dose-dependent (p=0.023) and significant reduction in CSF Abeta(42) concentration compared with those treated with placebo (difference in least squares mean change from baseline was -56.0 pg/mL, 95% CI -101.5 to -11.0; p=0.006). PBT2 had no effect on plasma biomarkers of AD or serum Zn(2+) and Cu(2+) concentrations. Cognition testing included ADAS-cog, MMSE, and a neuropsychological test battery (NTB). Of these tests, two executive function component tests of the NTB showed significant improvement over placebo in the PBT2 250 mg group: category fluency test (2.8 words, 0.1 to 5.4; p=0.041) and trail making part B (-48.0 s, -83.0 to -13.0; p=0.009). INTERPRETATION: The safety profile is favourable for the ongoing development of PBT2. The effect on putative biomarkers for AD in CSF but not in plasma is suggestive of a central effect of the drug on Abeta metabolism. Cognitive efficacy was restricted to two measures of executive function. Future trials that are larger and longer will establish if the effects of PBT2 on biomarkers and cognition that are reported here translate into clinical effectiveness.     

Role of apolipoproteins E and A-I: epistatic villains of triglyceride mediation in coronary heart disease

The epistatic effects of ApoE (HhaI) and ApoA-I (PstI) genes as the genetic modulators of lipid levels were investigated in 165 angiographically verified CHD patients and 120 controls of Punjab, a northwest province of India. It has been revealed that of all the genotypic combinations of ApoE and ApoA-I, E4 allele carriers (E4+) with P1P2 genotype (ApoA-I/PstI) had higher risk of CHD (OR 2.99, CI 1.31-6.8, P<0.01) which exacerbated (OR 3.44, CI 1.45-8.15, P<0.01) after adjustment with the confounders. Individually, neither ApoA-I nor ApoE was found to be associated with TG levels however, pairwise epistasis (additive x additive model) explored their significant synergistic contributions with raised TG levels (P<0.01).     

Acute effects of Helicobacter pylori extracts on gastric mucosal blood flow in the mouse

AIM： To investigate the mechanisms underlying the reduction in gastric blood flow induced by a luminal water extract of Hellcobacter pylori （HPE）. METHODS： The stomachs of isoflurane-anesthetized mice were exteriorized, and the mucosal surface exposed. Blood flow was measured with the laserDoppler technique, and systemic arterial blood pressure monitored. C57BL/6 mice were exposed to water extract produced from Hpylori strain 88-23. To investigate the role of a nerveor iNOS-mediated pathway, we used intraluminal lidocaine and iNOS-/- mice. Blood flow response to the endogenous nitric oxide synthase inhibitor asymmetric dimethyl arginine （ADMA） was also assessed. RESULTS： In wild-type mice, HPE decreased mucosal blood flow by approximately 30%. This reduction was abolished in iNOS-deficient mice, and by pre-treatment with lidocaine. Luminally applied ADMA resulted in reduction in blood flow similar to that observed in wildtype mice exposed to HPE. CONCLUSION： A H py/ori water extract reduces gastric mucosal blood flow acutely through iNOS- and nerve-mediated pathways.     

Mutation analysis of cases of sudden unexplained death, 15 years after death: Prompt genetic evaluation after resuscitation can save future lives

Introduction

The aim of this study is to use genetic mutation analysis to determine the cause of sudden unexpected death in young (SUDY) persons with normal autopsy findings, and to provide relatives with an identified cardiac mutation with suitable cardiovascular prevention.

Methods

We performed mutation analysis on blood samples from first-degree relatives of 25 cases with normal autopsy findings identified in the national Swedish study of sudden cardiac death in 15- to 35-year-olds from 1992 to 1999.

Results

We found three families with long QT syndrome through mutation screening, and the mutations were verified in two of the deceased. Eight family members were found to be mutation carriers and have been provided with suitable cardiovascular prevention. Mutation screening also identified a number of common polymorphisms in the individuals screened. Clinical history revealed one family each with short QT syndrome and hypertrophic cardiomyopathy, respectively, but no mutations were found in the family members or in the deceased. Two SCDs each had occurred in two of the affected families.

Conclusion

Cardiac/genetic evaluation of relatives long after SUDY can reveal a diagnosis in 5/25 (20%) of cases. Since DNA extraction of formalin fixed paraffin embedded samples is unreliable, it is important that blood or tissue samples be stored at autopsy of such cases. This can facilitate establishing a diagnosis and thereby save lives in the future.