To determine whether epithelial migration in the atelectatic tympanic membrane (secondary to any pathology) occurs in a similar fashion to that in the normal (non-pathological) tympanic membrane, by calculating and comparing the epithelial migration rate and pattern.
Blastocystis hominis is one of the most common intestinal protozoan parasites in humans, and reports have shown that blastocystosis is coupled with intestinal disorders. In the past, researchers have developed an in vitro model using B. hominis culture filtrates to investigate its ability in triggering inflammatory cytokine responses and transcription factors in human colonic epithelial cells. Studies have also correlated the inflammation by parasitic infection with cancer. The present study provides evidence of the parasite facilitating cancer cell growth through observing the cytopathic effect, cellular immunomodulation, and apoptotic responses of B. hominis, especially in malignancy. Here we investigated the effect of solubilized antigen from B. hominis on cell viability, using peripheral blood mononuclear cells (PBMCs) and human colorectal carcinoma cells (HCT116). The gene expressions of cytokines namely interleukin 6 (IL-6), IL-8, tumor necrosis factor alpha, interferon gamma, nuclear factor kappa light-chain enhancer of activated B cells (a gene transcription factor), and proapoptotic genes namely protein 53 and cathepsin B were also studied. Results exhibited favor the fact that antigen from B. hominis, at a certain concentration, could facilitate the growth of HCT116 while having the ability to downregulate immune cell responses (PBMCs). Therefore, there is a vital need to screen colorectal cancer patients for B. hominis infection as it possesses the ability to enhance the tumor growth.
The immune modulatory properties of mesenchymal stem cell (MSC) had brought a new insight in cell-based neotherapy. However, recent works of MSC are focused exclusively on bone marrow-derived MSC. We evaluated the immunogenicity of cord blood-derived MSC (CB-MSC) on T lymphocytes. Human peripheral blood mononuclear cells (PBMC) were prepared by density gradient separation and culture with the presence or absence of CB-MSC. PBMC were collected for activation analysis by flow cytometry at 24-, 48-, and 72- hours. The results showed that, CB-MSC does not stimulate nor inhibit T lymphocyte activation.
Normal tracheal mucociliary clearance is the key to maintaining the health and defense of respiratory airway. Therefore the present of cilia and mucous blanket are important for tracheal epithelium to function effectively. In the present study, we prepared a tissue engineered respiratory epithelium construct (TEREC) made of autologous respiratory epithelium cells, fibroblast and fibrin from sheep owns blood which replaced a created tracheal mucosal defect. Scanning electron microscopy (SEM) showed encouraging result where immature cilia were present on the surface of TEREC. This result indicates that engineered respiratory epithelium was able to function as normal tissue.
Bone marrow derived Mesenchymal stem cells (MSCs) were evaluated as an alternative source for tissue engineering of peripheral nerves. Human MSCs were subjected to a series of treatment with a reducing agent, retinoic acid and a combination of trophic factors. This treated MSCs differentiated into Schwann cells were characterized in vitro via flow cytometry analysis and immunocytochemically. In contrast to untreated MSCs, differentiated MSCs expressed Schwann cell markers in vitro, as we confirmed by flow cytometry analysis and immunocytochemically. These results suggest that human MSCs can be induced to be a substitute for Schwann cells that may be applied for nerve regeneration since it is difficult to grow Schwann cells in vitro.
The treatment of major burn injuries are a formidable challenge to the burn surgeon. Early aggressive surgery for deep to full thickness burn injuries is vital in the prevention of infection. The ultimate goal in major burn injuries is to prevent the onset of multi-resistant organisms and achieve early wound cover. The field of tissue engineering can help to expedite the healing of these burn wounds. The development of keratinocyte culture delivery system can be used clinically to fasten the healing process and save many lives.
The study of bioactivity of natural product is one of the major researches for drug discovery. The aim of this finding was to study the proliferation effect of Rhaphidophora korthalsii methanol extract on human PBMC and subsequently the cytotoxic effect of activated PBMC toward HepG2 human hepatocellular carcinoma. In this present study, MTT assay, cell cycle study and Annexin 5 binding assay were used to study the immunomodulatory and cytotoxic effects. In vitro cytotoxic screening of Rhaphidophora korthalsii methanol extract showed that the extract was non-toxic against hepatocellular carcinoma (HepG2). In contrast, the extract was able to stimulate the proliferation of human PBMC at 48 h and 72 h in MTT assay and cell cycle progress study. The application of immunomodulator in tumor research was studied by using MTT microcytotoxicity assay and flow cytometric Annexin V. Results indicated that pre-treated PBMC with Rhaphidophora korthalsii methanol extract induced the highest cytotoxicity (44.87+/-6.06% for MTT microcytotoxicity assay and 51.51+/-3.85% for Annexin V) toward HepG2. This finding demonstrates that Rhaphidophora korthalsii methanol extract are potent to stimulate the cytotoxic effect of immune cells toward HepG2.
Biosorption of cadmium (II) ions from aqueous solution onto immobilized cells of Pycnoporus sanguineus (P. sanguineus) was investigated in a batch system. Equilibrium and kinetic studies were conducted by considering the effect of pH, initial cadmium (II) concentration, biomass loading and temperature. Results showed that the uptake of cadmium (II) ions increased with the increase of initial cadmium (II) concentration, pH and temperature. Langmuir, Freundlich and Redlich-Peterson isotherm models were used to analyze the equilibrium data at different temperatures. Langmuir isotherm model described the experimental data well followed by Redlich-Peterson and Freundlich isotherm models. Biosorption kinetics data were fitted using pseudo-first, pseudo-second-order and intraparticle diffusion. It was found that the kinetics data fitted well the pseudo-second-order followed by intraparticle diffusion. Thermodynamic parameters such as standard Gibbs free energy (Delta G0), standard enthalpy (Delta H0) and standard entropy (Delta S0) were evaluated. The result showed that biosorption of cadmium (II) ions onto immobilized cells of P. sanguineus was spontaneous and endothermic nature.
Nine new indole alkaloids, rhazinoline (1), 19(S)-methoxytubotaiwine (2), 19(R)-methoxytubotaiwine (3), kopsamidine A (4), kopsamidine B (5), kopsinidine A (6), kopsinidine B (7), paucidactine C (8), and pericine N-oxide (9), in addition to several recently reported novel indoles and 34 other known ones, were obtained from the stem-bark extract of the Malayan Kopsia arborea. The structures were determined using NMR and MS analysis. Valparicine (12) showed pronounced cytotoxic effects against KB and Jurkat cells (IC(50) 13.0 and 0.91 microM, respectively).
To determine whether the postmyringoplasty tympanic membrane (TM) behaves in a similar way compared with a healthy nonoperated eardrum by calculating and comparing the epithelial migration rate and pattern.
Nipah virus is a zoonotic virus isolated from an outbreak in Malaysia in 1998. The virus causes infections in humans, pigs, and several other domestic animals. It has also been isolated from fruit bats. The pathogenesis of Nipah virus infection is still not well described. In the present study, Nipah virus replication kinetics were estimated from infection of African green monkey kidney cells (Vero) using the one-step SYBR Green I-based quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR) assay.
Anaemia is a frequent complication in patients with haematological malignancies and is caused by a variety of mechanisms including neoplastic cell infiltration into the bone marrow, haemolysis, nutritional deficiencies and defect in erythropoiesis or dysplastic anaemia as a result of the disease itself. However, acquired dysplastic anaemia which mimic congenital dyserythropoietic anaemia (CDA) type II morphology in the bone marrow is very rare. A 41-year-old Chinese man presented with refractory symptomatic anaemia in September 2001. He was clinically pale with no other significant physical finding. His initial peripheral blood picture showed normochromic normocytic anaemia with haemoglobin level of 26g/L, with no evidence of haemolysis and a poor reticulocyte response of 0.6%. Bone marrow aspiration was done and showed congenital dyserythropoietic anaemia (CDA) type II-like morphology. He was treated symptomatically with regular blood transfusions approximately every 3 weeks, until August 2002 when he developed multiple cervical lymphadenopathy with loss of appetite, loss of weight and low grade fever. Biopsy of the lymph node confirmed the diagnosis of small lymphocytic lymphoma. Staging with computed tomography and bone marrow aspirate revealed the infiltration of lymphoma cells into the marrow cavity consistent with the staging of IVB. This case report illustrates that CDA type II-like dysplastic anaemia can preceed the development of lymphoma.
An RT-PCR assay detected the t(4;11) translocation in two infants with acute lymphoblastic leukemia (ALL). Case P76 was a 10-month-old, female infant, who presented with a WBC of 137.4 x 10(9)/l and a pre-pre-B ALL immunophenotype. Case P120 was a 6-month-old female infant, with a WBC > 615 x 10(9)/l and a pre-pre-B ALL immunophenotype. RT-PCR of cDNA from both these cases generated a 656 bp and a 542 bp respectively, which sequencing confirmed as t(4;11) fusion transcripts. The primers and conditions selected for this assay are compatible with a one-step multiplex PCR for the main translocations in childhood ALL.
Hydroxyapatite (HA; Ca10(PO4)6(OH)2), is one of the significant implant materials used in Orthopaedics and Dental applications. However, synthetically produced HA may not be stable under ionic environment, which it will unavoidably encounter during its applications. In this paper, the in vitro effects of three HA materials derived from different resources, i.e. commercial HA (HAC), synthesised HA from pure chemicals (HAS) and synthesised HA from kapur sireh; derived traditionally from natural limestone (HAK), were studied. The HA disc samples were prepared and immersed in simulated body fluid (SBF) for 31-day period. The evaluation conducted focuses on the changes of the pH and the Calcium ion (Ca-ion) and Phosphate ion (P-ion) concentrations in the SBF solution, as well as the XRD and SEM data representing the reactions on the HA materials. From the XRD, it was found that HAK has the smallest crystallite sizes, which in turn affect the pH of the SBF during immersion. The Ca and P-ion concentrations generally decrease over time at different rates for different HA. Upon 1-day immersion in SBF, apatite growth was observed onto all three surfaces, which became more pronounced after 3-day immersion. However, the appetites formed were observed to be different in shapes and sizes. The reasons for the difference in the apatite-crystals and their subsequent effects on cells are still being investigated.
Patient own fibrin may act as the safest, cheapest and immediate available biodegradable scaffold material in clinical 1 tissue engineering. This study investigated the feasibility of using patient own fibrin isolated from whole blood to construct a new human cartilage, skin and bone. Constructed in vitro tissues were implanted on the dorsal part of the nude mice for in vivo maturation. After 8 weeks of implantation, the engineered tissues were removed for histological analysis. Our results demonstrated autologous fibrin has great potential as clinical scaffold material to construct various human tissues.
A 5-month-old Chinese male infant was referred to the University Hospital, Kuala Lumpur for persistent fever, generalised rash and abdominal distension. Clinically he was suspected to have haemophagocytic lymphohistiocytosis. Haematological findings including the presence of several abnormal giant granules in neutrophils and single large azurophilic granules in many lymphocytes and monocytes in the peripheral blood established the diagnosis of Chediak-Higashi syndrome. The patient responded to allogeneic bone marrow transplant. This paper discusses the characteristic features, clinical course and management of this rare disorder. We suggest that peripheral blood film examination for the abnormal giant granules in granulocytes is an essential investigation in all young children with frequent recurrent infections or who are suspected to have virus-associated haemophagocytic syndrome or familial haemophagocytic lymphohistiocytosis.
Histamine is established as a potent inflammatory mediator and it is known to increased endothelial permeability by promoting gap formation between endothelial cells. Previous studies have shown that aqueous extract of Bixa orellana leaves (AEBO) exhibits antihistamine activity in vivo, yet the mechanism of its action on endothelial barrier function remains unclear. Therefore, the current study aimed to determine the protective effect of AEBO against histamine-induced hyperpermeability in vitro.
Matched MeSH terms: Human Umbilical Vein Endothelial Cells/drug effects
Diabetes mellitus (DM) is a major worldwide health problem and its prevalence has been rapidly increasing in the last century. It is caused by defects in insulin secretion or insulin action or both, leading to hyperglycemia. Of the various types of DM, type 2 occurs most frequently. Multiple genes and their interactions are involved in the insulin secretion pathway. Insulin secretion is mediated through the ATP-sensitive potassium (KATP) channel in pancreatic beta cells. This channel is a heteromeric protein, composed of four inward-rectifier potassium ion channel (Kir6.2) tetramers, which form the pore of the KATP channel, as well as sulfonylurea receptor 1 subunits surrounding the pore. Kir6.2 is encoded by the potassium inwardly rectifying channel, subfamily J, member 11 (KCNJ11) gene, a member of the potassium channel genes. Numerous studies have reported the involvement of single nucleotide polymorphisms of the KCNJ11 gene and their interactions in the susceptibility to DM. This review discusses the current evidence for the contribution of common KCNJ11 genetic variants to the development of DM. Future studies should concentrate on understanding the exact role played by these risk variants in the development of DM.
While age-related insulin resistance and hyperinsulinemia are usually considered to be secondary to changes in muscle, the liver also plays a key role in whole-body insulin handling and its role in age-related changes in insulin homeostasis is largely unknown. Here, we show that patent pores called 'fenestrations' are essential for insulin transfer across the liver sinusoidal endothelium and that age-related loss of fenestrations causes an impaired insulin clearance and hyperinsulinemia, induces hepatic insulin resistance, impairs hepatic insulin signaling, and deranges glucose homeostasis. To further define the role of fenestrations in hepatic insulin signaling without any of the long-term adaptive responses that occur with aging, we induced acute defenestration using poloxamer 407 (P407), and this replicated many of the age-related changes in hepatic glucose and insulin handling. Loss of fenestrations in the liver sinusoidal endothelium is a hallmark of aging that has previously been shown to cause deficits in hepatic drug and lipoprotein metabolism and now insulin. Liver defenestration thus provides a new mechanism that potentially contributes to age-related insulin resistance.
Actinobacteria from the unique intertidal ecosystem of the mangroves are known to produce novel, bioactive secondary metabolites. A novel strain known as MUSC 136(T) (=DSM 100712(T) = MCCC 1K01246(T)) which was isolated from Malaysian mangrove forest soil has proven to be no exception. Assessed by a polyphasic approach, its taxonomy showed a range of phylogenetic and chemotaxonomic properties consistent with the genus of Streptomyces. Phylogenetically, highest similarity was to Streptomyces misionensis NBRC 13063(T) (99.6%) along with two other strains (>98.9% sequence similarities). The DNA-DNA relatedness between MUSC 136(T) and these type strains ranged from 22.7 ± 0.5% to 46.5 ± 0.2%. Overall, polyphasic approach studies indicated this strain represents a novel species, for which the name Streptomyces malaysiense sp. nov. is proposed. The potential bioactivities of this strain were explored by means of antioxidant and cytotoxic assays. Intriguingly, MUSC 136(T) exhibited strong antioxidative activities as evaluated by a panel of antioxidant assays. It was also found to possess high cytotoxic effect against HCT-116 cells, which probably mediated through altering p53 protein and intracellular glutathione levels. Chemical analysis of the extract using GC-MS further affirms that the strain produces chemopreventive related metabolites.