Bifidobacterium breve MCC1274 with glycosidic activity enhances in vivo isoflavone bioavailability

Polyphenols are plant derived compounds that exert many beneficial health effects to the human host. However, associated health benefits of dietary polyphenol are highly dependent on their intestinal metabolism, bioavailability, and absorption. Bifidobacteria, which represent the key members of gut microbiota, have been suggested to promote gut microbial homeostasis and may be involved in the metabolism of polyphenols. In this study, the capabilities of thirteen Bifidobacterium strains in hydrolysing polyphenol glycosides were evaluated. Among the tested strains, Bifidobacterium breve MCC1274 was found to possess the highest β-glucosidase activity and strong capability to convert daidzin and trans-polydatin to their aglycones; while kinetic analysis revealed that B. breve MCC1274 hydrolysed more than 50% of daidzin and trans-polydatin at less than 3 h of incubation. Further investigation using rats with an antibiotics-disturbed microbiome revealed that following the ingestion of daidzin glycoside, oral administration of B. breve MCC1274 significantly enhanced the plasma concentration of daidzein in rats pre-treated with antibiotics as compared to antibiotics-pre-treated control and non-treated control groups. The relative abundance of Actinobacteria and the total numbers of B. breve were also significantly higher in antibiotics-pre-treated rats administered with B. breve MCC1274 than that of the control groups. These findings suggest that B. breve MCC1274 is effective in enhancing the bioavailability of daidzein in the gut under dysbiosis conditions and may potentially improve intestinal absorption of isoflavones and promote human health.

Different physiological properties of human-residential and non-human-residential bifidobacteria in human health

Bifidobacteria have increasingly been shown to exert positive health benefits to humans, which are clearly reflected by their application in various commercialised dairy products and supplements. Bifidobacteria naturally inhabit a range of ecological niches and display substantial differences in their ecological adaptation among species. In general, bifidobacteria could be categorised into two major groups; bifidobacterial species of human origins as human-residential bifidobacteria (HRB) while other species which are the natural inhabitants of animals or environment as non-HRB. Current research has focused on the differential physiological features of HRB and non-HRB, such as metabolic capabilities, whilst comparative and functional genomic investigations have revealed the genetic attributes of bifidobacteria that may explain their colonisation affinities in human gut. It is becoming more apparent that distinct residential origins of bifidobacteria are likely contributed to their comparable adaptive health attributes on human host. Notably, debate still remains about the nature of bifidobacteria for use as human probiotics. Clinical evaluations involving supplementation of bifidobacteria of different origins point out the superiority of HRB in human host. Evidence also suggests that HRB especially infant-type HRB may exert better health-promoting effects and therefore serve as a better probiotic candidate for infant use. In this review, we aim to provide an overview of the genotypic and physiological differences of bifidobacteria associated with different residential origins and to shed light on the practical considerations for selection of bifidobacteria as probiotics in order to establish a healthy gut microbial community in humans.

Surgical treatment of adjacent instability after lumbar spine fusion

STUDY DESIGN

This study is a retrospective review of 39 patients with previous instrumented lumbar fusion who underwent secondary spine surgery for lumbar adjacent instability. To the authors' knowledge, this is the largest study of surgical treatment of lumbar adjacent instability in the literature to date.

OBJECT

This study evaluated the feasibility of adjacent instability treated with medial facetectomy, fusion with autologous bone grafting, and pedicle screw instrumentation.

SUMMARY OF BACKGROUND DATA

The surgical treatment of adjacent instability has seldom been discussed. Revision spine fusions are challenged by high pseudarthrosis rates.

METHODS

Thirty-nine patients with previous lumbar fusion underwent second lumbar spine surgery for adjacent instability. All were treated with autogenous posterolateral arthrodesis and transpedicle screw fixation in addition to decompressive laminectomy. Medical records, radiographs, and pain scores were obtained.

RESULTS

The clinical results were excellent or good in 76.9% of patients, and the radiographic fusion was successful in 37 (94.9%) of patients. Flat back was noted in 8 (20.5%) of patients. In 5 patients (12.8%), neighboring segment breakdown again developed, and 2 of those patients underwent a third lumbar fusion. Dural tear during operation occurred in 2 patients. One patient experienced cauda equina syndrome but recovered bladder function 1 month later.

CONCLUSION

Autogenous posterolateral arthrodesis combined with pedicle screw fixation led to successful radiologic and clinical outcome in patients with lumbar adjacent instability. Adequate decompression of the adjacent stenosis requires medial facetectomy, thus preventing aggressive nerve root manipulation and reducing the incidence of dural tear.

Extracellular matrix regulates the hepatocellular heat shock response

BACKGROUND

Cirrhosis is characterized by the accumulation of collagen within the extracellular matrix (ECM) of the liver and progressive hepatocellular dysfunction. Since recent studies have shown that the ECM can modulate cellular function, we examined whether the ECM could contribute to hepatocellular dysfunction. To address this question we examined hepatocyte behavior in two different ECM environments.

MATERIALS AND METHODS

Primary rat hepatocytes were cultured as a monolayer on collagen or as multicellular aggregates (spheroids) within a laminin-rich ECM. Hepatocytes were then compared for viability, response to proinflammatory cytokines, and their capacity to activate a heat shock response and adopt a thermotolerant phenotype. In addition, we compared the ability of prior heat shock exposure to protect hepatocytes from tumor necrosis factor (TNF) alpha/actinomycin-D-induced apoptosis in the two different ECM environments.

RESULTS

Hepatocytes cultured as a monolayer on collagen exhibited decreased viability, underwent spontaneous apoptosis, and displayed an attenuated cytokine-stimulated nitric oxide production compared to hepatocytes cultured as spheroids. In response to heat, hepatocytes in both ECM environments expressed inducible heat shock protein 70 (hsp72). But, only the hepatocyte spheroids exhibited thermotolerance in response to a subsequent thermal challenge. In contrast to previous reports, induction of the heat shock response failed to protect hepatocytes against TNFalpha-induced apoptosis.

CONCLUSIONS

These data demonstrate that the ECM can play an integral role in specific hepatocellular behaviors. Furthermore, the progressive deposition of collagen within the ECM, which is characteristic of fibrotic liver diseases, may directly contribute to the progressive hepatocellular dysfunction observed in cirrhosis. Hepatocellular viability, response to proinflammatory cytokines, heat shock response, and thermotolerance were all altered depending on the composition of the ECM. In contrast, TNFalpha-induced apoptosis was independent of the composition of the ECM.

Pulmonary embolism mimicking acute myocardial infarction

Pulmonary embolism is a major cause of death in the United States. A high index of suspicion is required to achieve an accurate diagnosis. We report a case of a patient with syncope, ischemic electrocardiographic changes, and an elevated troponin I level, presenting just like acute myocardial infarction. The case highlights the value of an early use of 2-dimensional echocardiography in obtaining an accurate diagnosis, thus avoiding unnecessary and inappropriate treatment.

Stenting of an anomalous left circumflex coronary artery arising from the right sinus of Valsalva

Anomalous origin of coronary arteries is rare, occurring in about 1% of patients undergoing cardiac catheterization. Coronary atherosclerosis is not uncommon in these patients. Percutaneous angioplasty of anomalous coronary arteries poses a particular technical challenge secondary to the vessel characteristics. Stenting of the anomalous coronary arteries has not been described previously. We report a 47-year-old man with unstable angina in whom a MULTI-LINK coronary stent was placed successfully in an anomalous circumflex coronary artery.

Acute myocardial infarction in a patient with von Willebrand disease

Coronary atherosclerosis is uncommon in patients with von Willebrand factor deficiency. Occurrence of acute myocardial infarction is even rarer in these patients. We report on a 69-year-old woman with a long-standing history of von Willebrand disease who presented with acute myocardial infarction. Thrombolytic therapy with rtPA, heparin, and aspirin, followed by percutaneous transluminal coronary angioplasty and coronary stenting, was performed without significant bleeding or other complications.

Segmental analysis of coronary arteries with equivalent plaque burden by intravascular ultrasound in patients with and without angiographically significant coronary artery disease

These IVUS-derived data indicate that failure of compensatory dilation is an important factor in the development of clinically and angiographically significant coronary artery disease independent of plaque burden. We observed an actual reduction in total vessel area at the most stenotic site in coronary arteries that had a quantitatively significant angiographic lesion.

Erythromycin induced torsades de pointes

Erythromycin is a widely used antibiotic in today's armamentarium of antibiotics. Although erythromycin induced ventricular tachyarrhythmia is rare, this potentially life-threatening reaction should be kept in mind. The relative rarity of 'torsades de pointes' arrhythmia suggests that other predisposing factors contribute to the acquired long QT syndrome. Since more and more macrolide products have been approved by the Food and Drug Administration for use in the United States, the potential problem with 'torsades de pointes' may exist with each of the macrolide antibiotic. Until the exact mechanisms of the arrhythmia are worked out, close monitoring of rhythms and QT intervals of high risk patients who require erythromycin is certainly advisable. Only a heightened awareness among the physicians and medical personnel can the adverse outcome be minimized.

Clinical applications of signal-averaged electrocardiography in patients after myocardial infarction

In conclusion, signal-averaged electrocardiography is a useful, noninvasive technique to identify patients after myocardial infarction at risk for future arrhythmic events, especially in conjunction to existing tools, such as 24 hour ambulatory monitoring, echocardiography, nucleotide angiography and coronary angiography. It has a limited positive predictive value, but has an excellent negative predictive value. The optimum time to do signal-averaged electrocardiograms after myocardial infarction is unclear, 6 to 14 days after myocardial infarction has the highest sensitivity. Time domain analysis remains the most common method used to record late potentials. The definition of late potential and the scoring of a high resolution electrocardiogram as normal and abnormal have not yet been resolved. The criteria proposed by the Task Force Committee of the European Society of Cardiology, the American Heart Association and the American College of Cardiology (see introduction) should be observed at present. Many studies on signal-averaging were done in the prethrombolytic era. In patients who have received thrombolytic therapy, the positive predictive value of signal-averaged electrocardiograms has decreased. There are other limitations in applying signal averaging technique. The faster the ventricular tachycardia is induced in electrophysiological studies, the shorter is the late potential. Thus, a faster tachycardia which causes sudden cardiac death may not be detected by late potentials. The management strategies for patients who have abnormal signal-averaged electrocardiograms after myocardial infarction have not be defined. One should note that any management strategy has to prove that it improves prognosis. More prospective, randomized clinical trials are required to address these issues.

L-tryptophan-related eosinophilia-myalgia syndrome: a case report

Eosinophilia-myalgia syndrome (EMS) is characterized by intense eosinophilia and, very often, debilitating generalized myalgia in the absence of infectious or neoplastic causation. The Centers for Disease Control have established that the latter two features, along with an eosinophil count greater than 1000 cells per cu mm, are criteria for the syndrome. EMS has been reported in epidemic proportions over the last several months. Early data strongly suggested that in at least a small percentage of patients the syndrome leads to death. Epidemiological work in New Mexico, Minnesota, and Oregon has linked EMS most impressively to L-tryptophan-containing products (LTCPS).