Calcium phosphate supplementation increases faecal Lactobacillus spp. in a randomised trial of young adults.

The aim of the studies was to determine the effects of calcium carbonate and calcium phosphate supplementation on faecal Lactobacillus spp., with and without a probiotic supplement, in healthy adults. Study 1 comprised of a randomised, double-blind, crossover design; participants (n=15) received 2 capsules/d of 250 mg elemental calcium as calcium carbonate (Ca1) and calcium phosphate (Ca2) each for 2-week periods, with 2-week baseline and washout periods. Study 2 was a randomised, double-blind, crossover design; participants (n=17) received 2 capsules/d of Lactobacillus helveticus R0052 and Lactobacillus rhamnosus R0011 (probiotic) alone, the probiotic with 2 capsules/d of Ca1, and probiotic with 2 capsules/d of Ca2 each for 2-week periods with 2-week baseline and washout periods. In both studies, stools were collected during the baseline, intervention and washout periods for Lactobacillus spp. quantification and qPCR analyses. Participants completed daily questionnaires of stool frequency and compliance. In Study 1, neither calcium supplement influenced viable counts of resident Lactobacillus spp., genome equivalents of lactic acid bacteria or stool frequency. In Study 2, faecal Lactobacillus spp. counts were significantly enhanced from baseline when the probiotic was administered with Ca2 (4.83±0.30, 5.79±0.31) (P=0.02), but not with Ca1 (4.98±0.31) or with the probiotic alone (5.36±0.31, 5.55±0.29) (not significant). Detection of L. helveticus R0052 and L. rhamnosus R0011 was significantly increased with all treatments, but did not differ among treatments. There were no changes in weekly stool frequency. Calcium phosphate co-administration may increase gastrointestinal survival of orally-administered Lactobacillus spp.

Outbreak of Legionnaires' disease in West Fife: review of environmental guidelines needed.

OBJECTIVES: The objectives of this study were to investigate the source of and outbreak of Legionnaires' disease in West Fife in 2004; to control the spread of legionella from this source; and to make recommendations for future practice based on the findings from the investigation. STUDY DESIGN: Outbreak investigation. METHODS: A multi-agency team investigated links between the cases of legionellosis using detailed interviews, movement mapping, a timeline and extensive environmental sampling. RESULTS: The investigation found evidence that individuals affected by legionella during this outbreak had been in, or near (within 800 m), sullage tanks in Rosyth Dockyard within a period of 4 months. CONCLUSIONS: In the absence of laboratory isolation of Legionella spp. from the human cases, it was impossible to state definitely that a previously unrecognized source of environmental legionella aerosolization was responsible for the outbreak. However, strong epidemiological and environmental evidence would support this hypothesis.

Pioglitazone improves endothelial function in non-diabetic patients with coronary artery disease.

OBJECTIVE: To test the hypothesis that pioglitazone, a peroxisome proliferator-activated receptor-gamma agonist, will improve endothelial function in non-diabetic subjects with coronary artery disease, we conducted a prospective study to evaluate the effect of this medication on the brachial artery vasomotor function and circulating markers of endothelial activation. METHODS: Baseline characteristics were collected. After initial endothelial function assessment, patients were treated with pioglitazone hydrochloride 30 mg daily. The medication was continued for 12 weeks and endothelial function was reassessed as well as the inflammatory markers. The study medication then was stopped, and all the tests were repeated 12 weeks later. RESULTS: Seventeen subjects completed all three-study phases. Mean age was 58 (range: 36-77 years). Compared with the baseline, the endothelium-dependent vasodilation improved significantly with the treatment (p < 0.001) from 4.4 +/- 3.9 to 8.4 +/- 4.1%, a relative increase of 91%. After withdrawal of treatment, the endothelium-dependent vasodilation returned towards baseline values. There was no change in endothelium-independent vasodilatation (12.27 +/- 6.35 to 13.9 +/- 9.23%, to 12.42 +/- 5.35%, p = 0.177). The urine asymmetric dimethlyarginine levels decreased significantly with the treatment, but also returned to the initial values after the wash-out period (1.27 +/- 0.5 micromol/ml to 0.97 +/- 0.3 micromol/ml to 1.34 +/- 0.5 micromol/ml, p = 0.017). No difference in the lipid profile, C-reactive protein, erythrocyte sedimentation rate, or fibrinogen levels was seen. CONCLUSION: Pioglitazone rapidly improves endothelial function in non-diabetic patients with coronary artery disease. This improvement is associated with a change in mean urinary asymmetric dimethylarginine levels, although a cause and effect cannot be determined from this investigation.

Non-Q-Wave Myocardial Infarction.

The treatment of non-Q-wave infarction involves the use of antithrombotic therapy (aspirin and heparin) along with appropriate antianginal medication to reduce myocardial oxygen demands and prevent coronary spasm. In certain high-risk patient subgroups (ie, those with recurrent ischemia, persistent or significant ST segment change, congestive heart failure, or hypotension with chest pain), the use of newer agents such as the platelet glycoprotein IIb/IIIa antagonists is indicated. The role of angiography appears to be changing. In the past, at least in the United States, angiography was performed on nearly all patients with non-Q-wave infarction. Now, risk stratification into high- and low-risk subgroups can be performed based on clinical criteria. In low-risk individuals, we recommend that noninvasive testing be performed before a decision is made about an invasive evaluation. In high-risk patients, it is appropriate to perform angiography and, based on the angiographic findings, to provide appropriate therapy. Although the results of the Veterans Affairs Non-Q-Wave Infarction Strategies in Hospital (VANQWISH) study suggest that if bypass surgery is required, it should not be performed acutely, we do not believe that this is necessarily correct. Therapy must be individualized based on the risk-benefit profile of acute revascularization. Furthermore, the use of percutaneous coronary intervention, particularly with the glycoprotein IIb/IIIa antagonists and stents, is expanding to include multivessel disease, even in the presence of left ventricular dysfunction. Again, we believe therapy must be individualized to include an estimate of short- and long-term risk versus benefit. In the future, however, more data from appropriately designed clinical trials will be required to establish evidence-based therapy.

Assessment of acute right ventricular dysfunction induced by right coronary artery occlusion using echocardiographic atrioventricular plane displacement.

Right ventricular (RV) systolic function analysis by echocardiography has traditionally required RV endocardial border definition with subsequent tracing and is often inaccurate or impossible in technically poor studies. The atrioventricular plane displacement (AVPD) method attempts to use the descent of the tricuspid annular ring, a reflection of the longitudinal shortening of the right ventricle, as a surrogate marker for RV systolic function. We hypothesized that RV ischemia induced during right coronary artery occlusion proximal to the major right ventricular branches would result in severe right ventricular systolic dysfunction detectable by the AVPD method. During this pilot study, seven patients undergoing elective proximal RCA angioplasty had echocardiographic measurement of RV AVPD performed at baseline (i.e., immediately prior to RCA balloon inflation), during the last 30 seconds of first RCA balloon inflation, and at 1 minute after balloon deflation (recovery). Lateral and medial RV AVPD were significantly reduced from baseline values during intracoronary balloon inflation. (Lateral: 2.45 cm +/- 0.22 vs 1.77 cm +/- 0.13, P < 0.001; medial: 1.46 cm +/- 0.37 vs 1.28 cm +/- 0.32, P < 0.05). Additionally, lateral and medial RV AVPD significantly returned towards baseline values during recovery. (Lateral: 2.39 cm +/- 0.20, P < 0.001; medial: 1.58 cm +/- 0.27, P = 0.01). At baseline, all lateral RV AVPD values were > 2.0 cm, whereas during balloon inflation all were < 2.0 cm. No such clear distinction was found in medial RV AVPD values. Proximal RCA angioplasty is associated with a significant reduction in lateral and medial RV AVPD. Thus RV AVPD may serve as a marker for RV systolic dysfunction.

In vivo demonstration of an antithrombin effect of abciximab.

Abciximab prolonged the activated clotting time (ACT) in a post hoc analysis from the Evaluation of IIb/IIIa Platelet Receptor Antagonist 7E3 in Preventing Ischemic Complications trial and an in vitro study has suggested an antithrombin effect of platelet glycoprotein IIb/IIIa inhibition. The purpose of this study was to evaluate the in vivo effects of abciximab on ACT and thrombin generation. In 46 patients undergoing coronary intervention, 24 received heparin and abciximab (group I), whereas 22 received heparin alone (group II). All received the same dose (70 U/kg) of heparin. Heparin was given after a baseline ACT, and in group I, abciximab was administered after the 5-minute ACT. Serial ACTs were recorded at baseline, 5, 10, 20, and every 30 minutes thereafter and at the procedure's end. No intervention including balloon angioplasty was performed until after the 20-minute ACT. The prothrombin fragment F1.2 (Nm/L) was measured at baseline, 20 minutes, and at the end of the procedure. Before (baseline) heparin and at 5 minutes, ACTs were similar. Abciximab prolonged ACT by a mean of 34 to 64 seconds starting with the 10-minute ACT and extending to the 50-minute ACT (all p <0.01 vs heparin alone). There was a progressive decrease in the F1.2 with abciximab, and baseline minus end F1.2 was 0.12 +/- 0.02 in group I versus 0.05 +/- 0.04 in group II, p <0.05. These data indicate a significant in vivo effect of abciximab plus heparin in increasing ACT and decreasing F1.2, results that are consistent with an effect on reducing thrombin generation.

Isolated acute papillary muscle infarction in the absence of coronary artery disease resulting in cardiogenic shock and emergent mitral valve replacement.

A 76-year-old woman presented to our institution with shortness of breath, weakness, and syncope. Evaluation revealed severe mitral regurgitation and cardiogenic shock secondary to a flail posterior mitral valve leaflet. An emergency cardiac catheterization did not demonstrate significant coronary artery disease. The patient was sent for an emergency mitral valve replacement. Intraoperatively, the posteromedial papillary muscle was found to be transected. Histological analysis, clinical presentation, and a review of the literature of isolated papillary muscle infarction are presented.

Multiple introductions of HIV-1 subtype E into the western hemisphere.

There are nine recognised genetic subtypes of HIV-1, and the epidemic in Southeast Asia is largely due to subtype E. We have investigated HIV-1 viral subtypes in 11 Uruguayan military personnel, six with infection acquired during a United Nations deployment to Cambodia and five with infection acquired in South America. We found subtype E in five of the six infections acquired in Southeast Asia, and subtype B in all five of the domestically acquired cases. These findings document multiple introductions of HIV-1 subtype E into the western hemisphere and mean that the genetic diversity of the global HIV-1 pandemic must be considered in strategies for epidemic control.

PIP: The genetic analysis of viruses from 11 HIV-infected Uruguayan military personnel, 6 of whom are thought to have acquired their infection while deployed as part of the UN Transitional Authority in Cambodia, is reported. They were screened for antibodies to HIV-1 before deployment, on return, and one month after return. 10 (.8%) of 1300 individuals acquired HIV-1 infection during overseas deployment. 6 of these 10 and 5 military personnel with domestically acquired infections volunteered for this study. The five had been diagnosed when tested as part of sentinel screening or at blood donation. Medical histories indicated that for all but 1 of the 11 subjects (who did not deploy to Cambodia), transmission most likely occurred through heterosexual exposures. The virus was successfully isolated by coculture in six individuals (four nondeployed, two deployed), and the genetic analyses were carried out on DNA prepared from cocultured peripheral blood mononuclear cells (PBMC) from these subjects. Genetic analyses of viruses from the other five subjects were done on DNA from primary PBMC. Phylogenetic analysis of the DNA sequences from the gp 120 fragment obtained from the five subjects who did not deploy and had not traveled outside South America revealed that all clustered within the B subtype of HIV-1. Of the six subjects who were infected while deployed to Cambodia, five harbored HIV-1 subtype E, while the sixth isolate (UR5) was subtype B. Cross-sectional surveys in several populations in Uruguay have revealed a low overall seroprevalence of HIV-1, with the highest prevalence (1.26% of 868 patients tested) found in a population from a sexually transmitted diseases clinic in Montevideo. The biological consequences of the introduction of subtype E HIV-1 into the western hemisphere are not known, but data from Thailand suggest that subtype E may be associated with a higher risk of heterosexual transmission than B.

Mechanism of activation of the vav protooncogene.

vav is a human locus that appears to be specifically expressed in cells of hematopoietic origin regardless of their differentiation lineage. This gene was first identified as a result of its malignant activation during the course of gene transfer assays (Katzav, S., Martin-Zanca, D., and Barbacid, M. EMBO J., 8: 2283-2290, 1989). In this study, we report the isolation of complementary DNA clones containing the entire coding sequence of the mouse vav protooncogene. Antisera raised against a peptide corresponding to a predicted hydrophilic domain have allowed us to identify the product of the vav gene as a 95,000 Da protein. Analysis of the deduced amino acid sequence of p95vav revealed an amino-terminal leucine-rich region not present in the activated vav oncogene. This region consists of an amphipathic helix-loop-helix followed by a leucine zipper, a structure reminiscent of the carboxy-terminal region of myc proteins and the steroid binding domain of nuclear receptors. In vitro mutagenicity studies have indicated that removal of the amphipathic helix-loop-helix is sufficient to activate the transforming potential of human and mouse vav protooncogenes. vav proteins also possess a cysteine-rich domain whose sequence predicts the formation of two putative metal binding-like domains, Cys-X2-Cys-X13-Cys-X2-Cys and His-X2-Cys-X6-Cys-X2-His. Replacement of some of these cysteine and histidine residues completely abolished the transforming activity of vav genes. Further examination of the alignment of cysteine residues in this region revealed an alternative structure, Cys-X2-Cys-X13-Cys-X2-Cys-X7-Cys-X6-Cys, which is reminiscent of the phorbol ester binding domain of protein kinase C. A similar domain has been recently identified in a second enzyme, diacylglycerol kinase. These structural similarities, along with its expression pattern, suggest that the vav protooncogene codes for a new type of signal-transducing molecule that may play an important role in controlling hematopoiesis.

Increased retinoblastoma gene expression is associated with late stages of differentiation in many different cell types.

The retinoblastoma (Rb) gene is a recessive oncogene or tumor-suppressor gene whose inactivation leads to the development of tumors. Recently, evidence pointing to a role for the Rb gene in the differentiation of certain human cell types has been presented. We have studied three mouse cell lineages to determine whether there is a correlation between Rb gene expression and differentiation. We find that induction of mouse erythroleukemia cell differentiation with either dimethylsulfoxide (DMSO) or hexamethylene bisacetamide (HMBA) leads to increased expression of Rb mRNA. Increased expression of Rb mRNA was also found in S2 myoblasts induced by mitogen depletion to become differentiated myotubes. In the B-cell lineage, Rb expression is low in pre-B and B cell lines but high in plasmacytomas, which represent late stages of B cell differentiation. Thus, in all three lineages (erythroid, muscle, and B-cell) late stages of differentiation are associated with increased amounts of Rb mRNA.

Continued withdrawal from the cell cycle and regulation of cellular genes in mouse erythroleukemia cells blocked in differentiation by the c-myc oncogene.

Constitutive expression of the c-myc oncogene blocks dimethyl sulfoxide (DMSO)-induced differentiation of mouse erythroleukemia (MEL) cells. During the first 12 h of treatment with DMSO, MEL cells undergo a temporary decrease in the level of c-myc mRNA, followed by a temporary withdrawal from the cell cycle. We found the same shutoff of DNA synthesis during the first 12 to 30 h after DMSO induction in normal MEL cells (which differentiate) and in c-myc-transfected MEL cells (which do not differentiate). We also examined whether deregulated c-myc expression grossly interfered with the regulation of gene expression during MEL cell differentiation. We used run-on transcription assays to monitor the rate of transcription of four oncogenes (c-myc, c-myb, c-fos, and c-K-ras); all except c-K-ras showed a rapid but temporary decrease in transcription after induction in both c-myc-transfected and control cells. Finally, we found the same regulation of cytoplasmic mRNA expression in both types of cells for four oncogenes and three housekeeping genes associated with growth. We conclude that in the MEL cell system, the effects of deregulated c-myc expression do not occur through a disruption of cell cycle control early in induction, nor do they occur through gross deregulation of gene expression.

Computed tomography of musculoskeletal tuberculosis.

The usefulness of computed tomography (CT) in the evaluation of musculoskeletal tuberculosis was assessed in 10 patients. In six tuberculosis affected the dorsal spine, in two the chest wall, in one the sacrum and sacroiliac joint, and in one the greater trochanter. At all sites the CT findings were qualitatively similar: specifically, destructive osseous changes associated with adjacent soft-tissue masses showing a characteristic rim enhancement. Soft-tissue calcification was present in 8 of the 10. In all patients, CT demonstrated more extensive involvement than could be seen on plain radiographs. In five patients, CT first suggested the diagnosis. We conclude that CT is helpful in the evaluation of patients with musculoskeletal tuberculosis.