Complete heart block induced by insertion of a pulmonary artery catheter

We report a case of complete heart block induced by insertion of a pulmonary artery catheter (PAC). A 74-year-old man was scheduled for off-pump coronary artery bypass grafting. The preoperative electrocardiogram revealed complete left bundle-branch block (LBBB). General anesthesia was induced with intravenous administration of midazolam 5.3 mg, fentanyl 110 microg and rocuronium 32 mg. General anesthesia was maintained with oxygen, air and sevoflurane. After a PAC was inserted via the right internal jugular vein and when it entered the right ventricle, complete heart block (CHB) associated with severe bradycardia occurred. Cardiopulmonary bypass (CPB) was required during the surgery and temporary epicardial pacing was instituted for weaning from CPB. Cardiac rhythm was restored to complete LBBB without any treatment postoperatively, but CHB recurred 9 seconds after the removal of PAC. The electrophysiologic study performed afterward showed an intact conduction pathway. Right bundle-branch block (RBBB) is one of complications induced by pulmonary artery catheterization. In the patients with underlying LBBB, transient RBBB produces CHB that could produce hemodynamic compromise. Therefore, we should carefully consider the indication of PAC in the patients with preexisting LBBB.     

Limnatis nilotica infestation in ram and kid in Dehloran city,Ilam province,west of Iran

Leech infestation can cause various clinical symptoms in human and animals. There are a few reports about this infestation in the world. In this report, we represented two cases of leech infestation of Limnatis nilotica in domestic kid and ram with anorexia, little respiratory disorders and restlessness in Dehloran city, Ilam province, west of Iran. Based on author''s knowledge, there is no report of leech infestation on ram and kid and the present case is the first report of internal hirudiniasis of ram and kid due to Limnatis niloticain in literature.     

Comparison of larvicidal, adulticidal and acaricidal activity of two geometrical butylidenephthalide isomers

Insecticidal and acaricidal activities of two geometrical isomers, (E)- and (Z)-butylidenephthalide isolated from Angelica acutiloba, against larvae and adults of fruit fly (Drosophila melanogaster), cat fleas (Ctenocephalides felis) and house dust mites (Dermatophagoides farinae and Tyrophagus putrescentiae) were investigated and compared with that of positive controls. (E)- and (Z)-Butylidenephthalide exhibited 50% lethal concentration (LC50) values of 2.07 and 0.94 micromol/ml of diet concentration against larvae of D. melanogaster, respectively. This indicated that two isomers of butylidenephthalide have geometrical stereoselectivity for larvicidal effect. Even though both (E)- and (Z)-butylidenephthalide also showed potent adulticidal and acaricidal activity against adults of D. melanogaster and two mites, there was no significant difference between two isomers. Insecticidal activity of both (E)- and (Z)-butylidenephthalide toward adults of C. felis was not detected even at the maximum concentration of 200 microg/cm2.     

Inhibition of intraocular fibrin formation after infusion of low-molecular-weight heparin during combined phacoemulsification-trabeculectomy surgery

PURPOSE: To evaluate the effect of intraocular infusion of dalteparin, a low-molecular-weight heparin (LMWH) administered in the infusion fluid to prevent early postoperative fibrin formation in combined phacoemulsification-trabeculectomy surgery (phacotrabeculectomy). SETTING: Farabi Eye Hospital, Tehran, Iran. METHODS: Standard combined phacotrabeculectomy was performed prospectively in a masked fashion in 60 eyes; 35 eyes received 5 IU/mL LMWH in the infusate and 25 eyes served as controls. Masked postoperative examinations assessed visual acuity, intraocular pressure (IOP), anterior chamber cell and flare, and fibrin formation with slitlamp examinations 1, 3, 7, 30, and 90 days after surgery. RESULTS: The rate of intraocular fibrin/membrane formation was significantly lower in the LMWH group than in the control group at each follow-up (P<.001, Student t test) . The amount of IOP was lower in LMWH group at each follow up (P<.01, Student t test). Final visual acuity was better in LMWH group (P = .03, Student t test). The frequency of synechia formation was lower in the LMWH group on day 90 (P = .002, chi-square test). CONCLUSIONS: Infusion of dalteparin, a LMWH, may be an effective inhibitor of postoperative fibrin formation in phacotrabeculectomy surgery. It may reduce the frequency of synechia formation and improve visual acuity. It may not be associated with increased risk for intraoperative or postoperative complications at the tested dose. This drug may be a useful adjunct in combined surgery.     

Human adenosine A(3) receptor leads to intracellular Ca(2+) mobilization but is insufficient to activate the signaling pathway via phosphoinositide 3-kinase gamma in mice

Selective antagonists for the adenosine A(3) receptor (A3AR), a member of the G protein-coupled receptors, have been indicated as potential drugs for anti-asthma or anti-inflammation. However, potent antagonists for the rodent A3AR have not been identified. To evaluate the pharmacological effects of human A3AR antagonists in mice, we here generated A3AR-humanized mice, in which the mouse A3AR gene was replaced by its human counterpart. The expression levels of human A3AR in the A3AR-humanized mice were equivalent to those of mouse A3AR in wild-type mice. Elevation of the intracellular Ca(2+) concentration induced by an A3AR agonist was observed in bone marrow-derived mast cells from the A3AR-humanized mice and this Ca(2+) mobilization was completely antagonized by a human A3AR antagonist. However, antigen-dependent degranulation was not potentiated by the A3AR agonist in the mast cells from A3AR-humanized mice. The agonist-stimulated human A3AR did not lead to the phosphorylation of either extracellular signal-regulated kinase 1/2 or protein kinase B in A3AR-humanized mice. The rate of human A3AR internalization in the mast cells was also markedly decreased compared with that of mouse A3AR in the mast cells. These results demonstrate that the human A3AR is insufficient to activate phosphoinositide 3-kinase gamma-dependent signaling pathways in mice, probably due to the uncoupling of member(s) of the G proteins, which are capable of activating phosphoinositide 3-kinase gamma, to the human A3AR, despite the mouse G protein(s) responsible for the Ca(2+) elevation are coupled with the human A3AR.     

A novel HIV-1 reporter virus with a membrane-bound Gaussia princeps luciferase

HIV-1 reporter viruses are a critical tool for investigating HIV-1 infection. By having a reporter gene incorporated into the HIV-1 genome, the expressed reporter protein acts as a specific tag, thus enabling specific detection of HIV-1 infected cells. Currently existing HIV-1 reporter viruses utilize reporters for the detection of HIV-1 infected cells by a single assay. A reporter virus enabling the detection of viral particles as well as HIV-1 infected cells by two assays can be more versatile for many applications. In this report, a novel reporter HIV-1 was generated by introducing a membrane-anchored form of the Gaussia princeps luciferase gene (mGluc) upstream of the nef gene in the HIV-1(NL4-3) genome using a picornaviral 2A-like sequence. The resulting HIV-1(NL4-3mGluc) virus expresses G. princeps luciferase efficiently on viral membrane and the cell surface of infected human T cell lines and primary peripheral blood mononuclear cells. This HIV-1 reporter is replication competent and the reporter gene mGluc is expressed during multiple rounds of infection. Importantly, viral particles can be detected by bioluminescence and infected cells can be detected simultaneously by bioluminescence and flow cytometric assays. With the versatility of two sensitive detection methods, this novel luciferase reporter has many applications such as cell-based screening for anti-HIV-1 agents or studies of HIV-1 pathogenicity.     

Microvesicles derived from mesenchymal stem cells: Potent organelles for induction of tolerogenic signaling

The adult bone contains a number of distinct populations of stem cells, including haematopoietic stem cells, mesenchymal stem cells, endothelial progenitor cells and fibrocytes. While haematopoietic stem cells are required to provide a lifelong supply of blood cells it is thought that the other populations of stem cells play a role in tissue regeneration and potentially disease. The chemokine CXCL12 is produced constitutively in the bone marrow and, acting via CXCR4, is critical in maintaining HSPCs in a quiescent state and retaining all subsets of stem and progenitor cells in the bone marrow environment. The cytokine G-CSF, used clinically to mobilize haematopoietic stem cells for bone marrow transplants, activates the sympathetic nervous system and bone marrow macrophages to reduce the expression of CXCL12 by bone marrow stromal cells, thereby promoting the exit of haematopoietic stem cells from the bone marrow. Understanding the molecular mechanisms underlying G-CSF stimulated mobilization has led to development of CXCR4 antagonists as fast acting mobilizing agents for haematopoietic stem cells. Evidence now suggests that CXCR4 antagonists can similarly mobilize distinct subsets of progenitor cells, namely the endothelial progenitor cells and mesenchymal stem cells, but this requires conditioning of the bone marrow with VEGF rather than G-CSF.