Antimicrobial activity of essential oils against Helicobacter pylori

Background. Helicobacter pylori is an important pathogen responsible for gastroduodenal diseases in humans. Although the eradication of H. pylori using antibiotics often improves gastroduodenal diseases, resistance to the antibiotics is emerging. Materials and Methods. The antimicrobial effect of essential oils and the development of resistance to the essential oils were evaluated in vitro and in vivo. Results. Thirteen essential oils used in this study completely inhibited the growth of H. pylori in vitro at a concentration of 0.1% (v/v). Cymbopogon citratus (lemongrass) and Lippia citriodora (lemon verbena) were bactericidal against H. pylori at 0.01% at pH 4.0 and 5.0. Resistance to lemongrass did not develop even after 10 sequential passages, whereas resistance to clarithromycin developed under the same conditions. In in vivo studies, the density of H. pylori in the stomach of mice treated with lemongrass was significantly reduced compared with untreated mice. Conclusions. These results demonstrate that the essential oils are bactericidal against H. pylori without the development of acquired resistance, suggesting that essential oils may have potential as new and safe agents for inclusion in anti‐H. pylori regimens.     

Mg-ATPase and CA2+ activated myosin ATPase activity in ventricular myofibrils from non-failing and diseased human hearts – effects of calcium sensitizing agents MCI-154, DPI 201–106, and caffeine

We investigated the effects of two purported calcium sensitizing agents, MCI-154 and DPI 201–106, and a known calcium sensitizer caffeine on Mg-ATPase (myofibrillar ATPase) and myosin ATPase activity of left ventricular myofibrils isolated from non-failing, idiopathic (IDCM) and ischemic cardiomyopathic (ISCM) human hearts (i.e. failing hearts). The myofibrillar ATPase activity of non-failing myofibrils was higher than that of diseased myofibrils. MCI-154 increased myofibrillar ATPase Ca²⁺ sensitivity in myofibrils from non-failing and failing human hearts. Effects of caffeine similarly increased Ca²⁺ sensitivity. Effects of DPI 201–106 were, however, different. Only at the 10^–6 M concentration was a significant increase in myofibrillar ATPase calcium sensitivity seen in myofibrils from non-failing human hearts. In contrast, in myofibrils from failing hearts, DPI 201–106 caused a concentration-dependent increase in myofibrillar ATPase Ca²⁺ sensitivity. Myosin ATPase activity in failing myocardium was also decreased. In the presence of MCI-154, myosin ATPase activity increased by 11, 19, and 24% for non-failing, IDCM, and ISCM hearts, respectively. DPI 201–106 caused an increase in the enzymatic activity of less than 5% for all preparations, and caffeine induced an increase of 4, 11, and 10% in non-failing, IDCM and ISCM hearts, respectively. The mechanism of restoring the myofibrillar Ca²⁺ sensitivity and myosin enzymatic activity in diseased human hearts is most likely due to enhancement of the Ca²⁺ activation of the contractile apparatus induced by these agents. We propose that myosin light chain-related regulation may play a complementary role to the troponin-related regulation of myocardial contractility.     

A missense mutation (GGC[435Gly]-->AGC[Ser]) in exon 8 of the CYP11B2 gene inherited in Japanese patients with congenital hypoaldosteronism

OBJECTIVES: To clarify the underlying molecular mechanism of corticosterone methyl oxidase type II (CMO II) deficiency, Japanese patients newly diagnosed with CMO II deficiency were investigated. METHODS: We analyzed the patients' genomic DNA sequence on all 9 exons of the CYP11B2 gene. In addition, restriction fragment length polymorphism (RFLP) analysis and expression studies were performed. RESULTS: The analysis showed that the patients homozygously retained a missense mutation, Gumacr;GC[435Gly]-->Aumacr;GC[Ser], in the CYP11B2 gene. Expression studies indicated that the steroid 18-hydroxylase/oxidase activities of the mutant enzyme were substantially reduced. CONCLUSION: These results support the hypothesis that this mutation causes CMO II deficiency in the patients, and are in accordance with our theory that the partial loss of P-450(C18) activities causes CMO II deficiency.     

αvβ3 expression on blood vessels and melanoma cells in primary lesions; differential association with tumor progression and clinical prognosis

The α_vβ₃ integrin has emerged as a key mediator in angiogenesis. Its role in tumor-induced angiogenesis is supported by its up-regulation in vivo in the vasculature of a number of different types of carcinoma. The potential clinical significance of α_vβ₃ expression on blood vessels in carcinomas is suggested by its association with tumor progression. Currently no information is available about the clinical significance of α_vβ₃ expression on the vasculature of lesions of melanocytic origin. Since we have previously found that α_vβ₃ expression on melanoma cells in primary lesions is associated with a poor prognosis, in the present study we have compared α_vβ₃ expression on blood vessels and on cells of melanocytic origin in nevi and in malignant melanoma lesions. In addition we have examined the lesions for expression of the α_v subunit to gain information on the regulation of α_vβ₃ expression on endothelial cells and on cells of the melanocyte lineage. α_vβ₃ expression on endothelial cells and on melanocytic cells was a relatively sensitive and specific marker for malignant lesions. However, α_vβ₃ expression on endothelial cells in primary melanoma lesions was not associated with the prognosis of the disease. The α_v subunit and the α_vβ₃ complex were differentially expressed on endothelial cells and on melanocytic cells, implying that different regulatory pathways control their expression. This finding may account for the differential clinical significance of α_vβ₃ expression on tumor vasculature and on melanoma cells we observed in our patient cohort. Lastly, α_vβ₃ may be a useful target for immunotherapeutic approaches in melanoma because of its high expression on the vasculature of all metastatic lesions tested and its restricted distribution in normal tissues. Received: 18 February 2000 / Accepted: 12 April 2000     

Isolation of Borna disease virus from human brain tissue

Serological and molecular epidemiological studies indicate that Borna disease virus (BDV) can infect humans and is possibly associated with certain neuropsychiatric disorders. We examined brain tissue collected at autopsy from four schizophrenic patients and two healthy controls for the presence of BDV markers in 12 different brain regions. BDV RNA and antigen was detected in four brain regions of a BDV-seropositive schizophrenic patient (P2) with a very recent (2 years) onset of disease. BDV markers exhibited a regionally localized distribution. BDV RNA was found in newborn Mongolian gerbils intracranially inoculated with homogenates from BDV-positive brain regions of P2. Human oligodendroglia (OL) cells inoculated with brain homogenates from BDV-positive gerbils allowed propagation and isolation of BDVHuP2br, a human brain-derived BDV. Virus isolation was also possible by transfection of Vero cells with ribonucleoprotein complexes prepared from BDV-positive human and gerbil brain tissues. BDVHuP2br was genetically closely related to but distinct from previously reported human- and animal-derived BDV sequences.     

Dorsal specification in blastoderm at the blastula stage in the goldfish, Carassius auratus

The teleost dorsoventral axis cannot be morphologically distinguished before gastrulation. Previous studies by the current authors have shown that localized dorsalizing activity in the yolk cell (YC) induces the dorsal tissues in the overlying blastoderm. In order to examine whether or not dorsal blastomeres are committed to their dorsal fate before the gastrula stage, a variety of transplant operations were performed in goldfish blastoderms at the mid- to late-blastula stages. When the blastoderm was cut from the YC, rotated horizontally at 180°, and recombined with the YC, the blastoderm frequently developed two axes, indicating that dorsal blastomeres of the blastula had already acquired the ability to differentiate into the organizer in the absence of dorsalizing signals from the YC. This result was further confirmed by experiments using ventralized embryos in which no dorsal structures formed: the axis formation was frequently observed in the normal blastoderm combined with the ventralized YC at the blastula stage. However, the axes formed in the absence of dorsal information from the YC exhibited a lower dorso-anterior index. Furthermore, the dorsal specification was not stably maintained when the dorsal cells were located far from the YC. These results suggest that the inductive and permissive influence of the YC may be required for the blastoderm to undergo full dorsal differentiation.     

Correlation between genetic and cytogenetic maps of the rat

To correlate rat genetic linkage maps with cytogenetic maps, we localized 25 new cosmid-derived simple sequence length polymorphism (SSLP) markers and 14 existing genetic markers on cytogenetic bands of chromosomes, using fluorescence in situ hybridization (FISH). Next, a total of 58 anchor loci, consisting of the 39 new and 19 previously reported ones, were integrated into the genetic linkage maps. Since most of the new anchor loci were developed to be localized near the terminals of the genetic or cytogenetic maps for each chromosome, the orientation and coverage of the whole genetic linkage maps were determined or confirmed with respect to the cytogenetic maps. Thus, we provide here a new base for rat genetic maps. Received: 9 September 1997 / Accepted: 11 November 1997     

Autologous Transplantation of Oral Mucosal Epithelial Cell Sheets Cultured on an Amniotic Membrane Substrate for Intraoral Mucosal Defects

The human amniotic membrane (AM) is a thin intrauterine placental membrane that is highly biocompatible and possesses anti-inflammatory and anti-scarring properties. Using AM, we developed a novel method for cultivating oral mucosal epithelial cell sheets. We investigated the autologous transplantation of oral mucosal epithelial cells cultured on AM in patients undergoing oral surgeries. We obtained specimens of AM from women undergoing cesarean sections. This study included five patients without any history of a medical disorder who underwent autologous cultured oral epithelial transplantation following oral surgical procedures. Using oral mucosal biopsy specimens obtained from these patients, we cultured oral epithelial cells on an AM carrier. We transplanted the resultant cell sheets onto the oral mucosal defects. Patients were followed-up for at least 12 months after transplantation. After 2–3 weeks of being cultured on AM, epithelial cells were well differentiated and had stratified into five to seven layers. Immunohistochemistry revealed that the cultured cells expressed highly specific mucosal epithelial cell markers and basement membrane proteins. After the surgical procedures, no infection, bleeding, rejection, or sheet detachment occurred at the reconstructed sites, at which new oral mucous membranes were evident. No recurrence was observed in the long-term follow-up, and the postoperative course was excellent. Our results suggest that AM-cultured oral mucosal epithelial cell sheets represent a useful biomaterial and feasible method for oral mucosal reconstruction. However, our primary clinical study only evaluated their effects on a limited number of small oral mucosal defects.