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Fulltext Cloning and expression of highly pathogenic avian influenza virus full-length nonstructural gene in Pichia pastoris

Abubakar MB, Aini I, Omar AR, Hair-Bejo M

J Biomed Biotechnol, 2011;2011:414198.
PMID: 21541235 DOI: 10.1155/2011/414198

Avian influenza (AI) is a highly contagious and rapidly evolving pathogen of major concern to the poultry industry and human health. Rapid and accurate detection of avian influenza virus is a necessary tool for control of outbreaks and surveillance. The AI virus A/Chicken/Malaysia/5858/2004 (H5N1) was used as a template to produce DNA clones of the full-length NS1 genes via reverse transcriptase synthesis of cDNA by PCR amplification of the NS1 region. Products were cloned into pCR2.0 TOPO TA plasmid and subsequently subcloned into pPICZαA vector to construct a recombinant plasmid. Recombinant plasmid designated as pPICZαA-NS1 gene was confirmed by PCR colony screening, restriction enzyme digestion, and nucleotide sequence analysis. The recombinant plasmid was transformed into Pichia pastoris GS115 strain by electroporation, and expressed protein was identified by SDS-PAGE and western blotting. A recombinant protein of approximately ~28 kDa was produced. The expressed protein was able to bind a rabbit polyclonal antibody of nonstructural protein (NS1) avian influenza virus H5N1. The result of the western blotting and solid-phase ELISA assay using H5N1 antibody indicated that the recombinant protein produced retained its antigenicity. This further indicates that Pichia pastoris could be an efficient expression system for a avian influenza virus nonstructural (NS1).

Matched MeSH terms: Rabbits
Fulltext Characterization of Burkholderia pseudomallei protein BPSL1375 validates the Putative hemolytic activity of the COG3176 N-Acyltransferase family

Ahmad L, Hung TL, Mat Akhir NA, Mohamed R, Nathan S, Firdaus-Raih M

BMC Microbiol, 2015;15:270.
PMID: 26597807 DOI: 10.1186/s12866-015-0604-4

There are still numerous protein subfamilies within families and superfamilies that do not yet have conclusive empirical experimental evidence providing a specific function. These proteins persist in databases with the annotation of a specific 'putative' function made by association with discernible features in the protein sequence.

Matched MeSH terms: Rabbits
Fulltext Changes in the vascular cell adhesion molecule-1, intercellular adhesion molecule-1 and c-reactive protein following administration of aqueous extract of piper sarmentosum on experimental rabbits fed with cholesterol diet

Amran AA, Zakaria Z, Othman F, Das S, Al-Mekhlafi HM, Nordin NA

Lipids Health Dis, 2011 Jan 09;10:2.
PMID: 21214952 DOI: 10.1186/1476-511X-10-2

BACKGROUND: Inflammation process plays an important role in the development of atherosclerosis. Hypercholesterolemia is one of the major risk factors for atherosclerosis. The present study aimed to evaluate the effect of aqueous extract of Piper sarmentosum (P.s) on inflammatory markers like vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and C-reactive protein (CRP).
METHODS: Forty two male New Zealand white rabbits were divided equally into seven groups; (i) C- control group fed normal rabbit chow (ii) CH- cholesterol diet (1%cholesterol) (iii) X1- 1% cholesterol with water extract of P.s (62.5 mg/kg) (iv) X2- 1% cholesterol with water extract of P.s (125 mg/kg (v) X3- 1% cholesterol with water extract of P.s (250 mg/kg) (vi) X4- 1% cholesterol with water extract of P.s (500 mg/kg) and (vii) SMV group fed with 1% cholesterol supplemented with simvistatin drug (1.2 mg/kg). All animals were treated for 10 weeks. Blood serum was taken for observing the inflammatory markers at the beginning and end of the experiment.
RESULTS: Rabbits fed with 1% cholesterol diet (CH) showed significant increase in the level of VCAM-1, ICAM-1 and CRP compared to the C group. The levels of VCAM-1, ICAM-1 and CRP in the 1% cholesterol group and supplemented with P.s (500 mg/kg) were significantly reduced compared to the cholesterol group. Similar results were also reported with simvistatin group.
CONCLUSION: These results suggest that the supplementation of Piper sarmentosum extract could inhibit inflammatory markers which in turn could prevent atherosclerosis.

Matched MeSH terms: Rabbits
Permeation Studies of Captopril Transdermal Films Through Human Cadaver Skin

Nair RS, Nair S

Curr Drug Deliv, 2015;12(5):517-23.
PMID: 25675336

Mortality rate due to heart diseases increases dramatically with age. Captopril is an angiotensin converting enzyme inhibitor (ACE) used effectively for the management of hypertension. Due to short elimination half-life of captopril the oral dose is very high. Captopril is prone to oxidation and it has been reported that the oxidation rate of captopril in skin tissues is considerably low when compared to intestinal tissues. All these factors make captopril an ideal drug candidate for transdermal delivery. In this research work an effort was made to formulate transdermal films of captopril by utilizing polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA) as film formers and polyethylene glycol 400 (PEG400) as a plasticizer. Dimethyl sulfoxide (DMSO) and dimethylformamide (DMF) were used as permeation enhancers. Physicochemical parameters of the films such as appearance, thickness, weight variation and drug content were evaluated. The invitro permeation studies were carried out through excised human cadaver skin using Franz diffusion cells. The in-vitro permeation studies demonstrated that the film (P4) having the polymer ratio (PVP:PVA = 80:20) with DMSO (10%) resulted a promising drug release of 79.58% at 24 hours with a flux of 70.0 µg/cm(2)/hr. No signs of erythema or oedema were observed on the rabbit skin as a result of skin irritation study by Draize test. Based on the stability report it was confirmed that the films were physically and chemically stable, hence the prepared films are very well suited for transdermal application.

Matched MeSH terms: Rabbits
EPA-coated titanium implants promote osteoconduction in white New Zealand rabbits

Mustafa A, Lung CY, Mustafa NS, Mustafa BA, Kashmoola MA, Zwahlen RA, et al.

Clin Oral Implants Res, 2016 Mar;27(3):303-9.
PMID: 25393376 DOI: 10.1111/clr.12525

OBJECTIVES: To investigate the effect of eicosapentaenoic acid (EPA)-coated Ti implants on osteoconduction in white New Zealand rabbit mandibles.
MATERIAL AND METHODS: Sandblasted and cleansed planar titanium specimens with a size of 5 × 5 × 1 mm were coated on one side with 0.25 vol% eicosapentaenoic acid (EPA). The other side of the specimens was kept highly polished (the control side). These specimens were inserted in rabbit mandibles. Twelve rabbits were randomly assigned into three study groups (n = 4). The rabbits were sacrificed at 4, 8, and 12 weeks. The harvested specimens with the implants were assessed for new bone formation on both sides of the implant using CBCT, conventional radiographs, and the biaxial pullout test. The results were statistically analyzed by a nonparametric Kruskal-Wallis test and Friedman's test as multiple comparisons and by Brunner-Langer nonparametric mixed model approach (R Software).
RESULTS: A significant osteoconductive bone formation was found on the EPA-coated Ti implant surface (P < 0.05) at 8 weeks when compared to the polished surface (control). Biaxial pullout test results showed a significant difference (P < 0.05) after 8 and 12 weeks with a maximum force of 243.8 N, compared to 143.25 N after 4 week.
CONCLUSION: EPA implant coating promoted osteoconduction on the Ti implant surfaces, enhancing the anchorage of the implant to the surrounding bone in white New Zealand rabbits.

Matched MeSH terms: Rabbits
Fulltext Repair of segmental load-bearing bone defect by autologous mesenchymal stem cells and plasma-derived fibrin impregnated ceramic block results in early recovery of limb function

Ng MH, Duski S, Tan KK, Yusof MR, Low KC, Rose IM, et al.

Biomed Res Int, 2014;2014:345910.
PMID: 25165699 DOI: 10.1155/2014/345910

Calcium phosphate-based bone substitutes have not been used to repair load-bearing bone defects due to their weak mechanical property. In this study, we reevaluated the functional outcomes of combining ceramic block with osteogenic-induced mesenchymal stem cells and platelet-rich plasma (TEB) to repair critical-sized segmental tibial defect. Comparisons were made with fresh marrow-impregnated ceramic block (MIC) and partially demineralized allogeneic bone block (ALLO). Six New Zealand White female rabbits were used in each study group and three rabbits with no implants were used as negative controls. By Day 90, 4/6 rabbits in TEB group and 2/6 in ALLO and MIC groups resumed normal gait pattern. Union was achieved significantly faster in TEB group with a radiological score of 4.50 ± 0.78 versus ALLO (1.06 ± 0.32), MIC (1.28 ± 0.24), and negative controls (0). Histologically, TEB group scored the highest percentage of new bone (82% ± 5.1%) compared to ALLO (5% ± 2.5%) and MIC (26% ± 5.2%). Biomechanically, TEB-treated tibiae achieved the highest compressive strength (43.50 ± 12.72 MPa) compared to those treated with ALLO (15.15 ± 3.57 MPa) and MIC (23.28 ± 6.14 MPa). In conclusion, TEB can repair critical-sized segmental load-bearing bone defects and restore limb function.

Matched MeSH terms: Rabbits
Goniothalamin enhances the ATPase activity of the molecular chaperone Hsp90 but inhibits its chaperone activity

Yokoyama Y, Ohtaki A, Jantan I, Yohda M, Nakamoto H

J. Biochem., 2015 Mar;157(3):161-8.
PMID: 25294885 DOI: 10.1093/jb/mvu061

Hsp90 is an ATP-dependent molecular chaperone that is involved in important cellular pathways such as signal transduction pathways. It is a potential cancer drug target because it plays a critical role for stabilization and activation of oncoproteins. Thus, small molecule compounds that control the Hsp90 function are useful to elucidate potential lead compounds against cancer. We studied effect of a naturally occurring styryl-lactone goniothalamin on the activity of Hsp90. Although many drugs targeting Hsp90 inhibit the ATPase activity of Hsp90, goniothalamin enhanced rather than inhibited the ATPase activity of a cyanobacterial Hsp90 (HtpG) and a yeast Hsp90. It increased both K(m) and k(cat) of the Hsp90s. Domain competition assays and tryptophan fluorescence measurements with various truncated derivatives of HtpG indicated that goniothalamin binds to the N-terminal domain of HtpG. Goniothalamin did not influence on the interaction of HtpG with a non-native protein or the anti-aggregation activity of HtpG significantly. However, it inhibited the activity of HtpG that assists refolding of a non-native protein in cooperation with the Hsp70 chaperone system. This is the first report to show that a small molecule that binds to the N-terminal domain of Hsp90 activates its ATPase activity, while inhibiting the chaperone function of Hsp90.

Matched MeSH terms: Rabbits
Effects of aeration rate on degradation process of oil palm empty fruit bunch with kinetic-dynamic modeling

Talib AT, Mokhtar MN, Baharuddin AS, Sulaiman A

Bioresour Technol, 2014 Oct;169:428-38.
PMID: 25079208 DOI: 10.1016/j.biortech.2014.07.033

The effect of different aeration rates on the organic matter (OM) degradation during the active phase of oil palm empty fruit bunch (EFB)-rabbit manure co-composting process under constant forced-aeration system has been studied. Four different aeration rates, 0.13 L min(-1) kg(DM)(-1),0.26 L min(-1) kg(DM)(-1),0.49 L min(-1) kg(DM)(-1) and 0.74 L min(-1) kg(DM)(-1) were applied. 0.26 L min(-1) kg(DM)(-1) provided enough oxygen level (10%) for the rest of composting period, showing 40.5% of OM reduction that is better than other aeration rates. A dynamic mathematical model describing OM degradation, based on the ratio between OM content and initial OM content with correction functions of moisture content, free air space, oxygen and temperature has been proposed.

Matched MeSH terms: Rabbits
The use of autologous fibrin as a scaffold for cultivating autologous conjunctiva in the treatment of conjunctival defect

Safinaz MK, Norzana AG, Hairul Nizam MH, Ropilah AR, Faridah HA, Chua KH, et al.

Cell Tissue Bank, 2014 Dec;15(4):619-26.
PMID: 24633432 DOI: 10.1007/s10561-014-9436-y

The purpose of this study was to compare the use of autologous fibrin to human amniotic membrane (HAM) as a scaffold in cultivating autologous conjunctiva for transplantation in treatment of conjunctival defect. An experimental study was performed using 18 adult New Zealand white strain rabbits which were divided into 3 groups. Each group consists of 6 rabbits. The conjunctiva on the temporal site was excised to create a conjunctival epithelial defect. The excised area in the Group 1 was transplanted with autologous conjunctiva cultivated on autologous fibrin; Group 2 was transplanted with autologous conjunctiva cultivated on HAM and Group 3 was left bare. The rabbits were followed up at regular intervals until 6 weeks. The mean period of complete conjunctival epithelization was 11.50 ± 8.22 days for the autologous fibrin group, 15.33 ± 11.80 days for the HAM group and 25.33 ± 5.32 days in the bare sclera group. The epithelization rate for the autologous fibrin group was faster compared to the other two groups. However all the results were not statistically significant (p value >0.05). There were no postoperative complications noted during the follow up. Autologous fibrin is comparable to HAM as a scaffold for cultivation of conjunctiva in the treatment of conjunctival defect.

Matched MeSH terms: Rabbits
Fulltext Effect of acacia honey on cultured rabbit corneal keratocytes

Ker-Woon C, Abd Ghafar N, Hui CK, Mohd Yusof YA

BMC Cell Biol., 2014;15:19.
PMID: 24885607 DOI: 10.1186/1471-2121-15-19

Acacia honey is a natural product which has proven to have therapeutic effects on skin wound healing, but its potential healing effects in corneal wound healing have not been studied. This study aimed to explore the effects of Acacia honey (AH) on corneal keratocytes morphology, proliferative capacity, cell cycle, gene and protein analyses. Keratocytes from the corneal stroma of six New Zealand white rabbits were isolated and cultured until passage 1. The optimal dose of AH in the basal medium (FD) and medium containing serum (FDS) for keratocytes proliferation was identified using MTT assay. The morphological changes, gene and protein expressions of aldehyde dehydrogenase (ALDH), marker for quiescent keratocytes and vimentin, marker for fibroblasts were detected using q-RTPCR and immunocytochemistry respectively. Flowcytometry was performed to evaluate the cell cycle analysis of corneal keratocytes.

Matched MeSH terms: Rabbits
Selective anticancer copper(II)-mixed ligand complexes: targeting of ROS and proteasomes

Ng CH, Kong SM, Tiong YL, Maah MJ, Sukram N, Ahmad M, et al.

Metallomics, 2014 Apr;6(4):892-906.
PMID: 24549332 DOI: 10.1039/c3mt00276d

Copper compounds can be alternatives to platinum-based anticancer drugs. This study investigated the effects of a series of ternary copper(II) complexes, [Cu(phen)(aa)(H2O)]NO3·xH2O 1-4 (phen = 1,10-phenanthroline; aa = gly (1), DL-ala (2), sar (3), C-dmg (4)), on metastatic and cisplatin-resistant MDA-MB-231 breast cancer cells and MCF10A non-cancerous breast cells, and some aspects of the mechanisms. These complexes were distinctively more antiproliferative towards and induced greater apoptotic cell death in MDA-MB-231 than in MCF10A cells. 2 and 4 could induce cell cycle arrest only in cancer cells. Further evidence from DCFH-DA assay showed higher induction of reactive oxygen species (ROS) in treated cancer cells but minimal ROS increase in normal cells. DNA double-strand breaks, via a γ-H2AX assay, were only detected in cancer cells treated with 5 μM of the complexes. These complexes poorly inhibited chymotrypsin-like activity in the 20S rabbit proteasome while they did not inhibit the three proteolytic sites of MDA-MB-231 cells at 10 μM. However, the complexes could inhibit degradation of ubiquinated proteins of MDA-MB-231 cells. In addition, compound 4 was found to be effective against cervical (Hela), ovarian (SKOV3), lung (A549, PC9), NPC (Hone1, HK1, C666-1), breast (MCF7, T47D), lymphoma and leukemia (Nalmawa, HL60) and colorectal (SW480, SW48, HCT118) cancer cell lines with IC50 values (24 h) in the 1.7-19.0 μM range. Single dose NCI60 screening of 4 showed the complex to be highly cytotoxic to most cancer cell types and more effective than cisplatin.

Matched MeSH terms: Rabbits
Fulltext Construction and evaluation of V. cholerae O139 mutant, VCUSM21P, as a safe live attenuated cholera vaccine

Murugaiah C, Nik Mohd Noor NZ, Mustafa S, Manickam R, Pattabhiraman L

PLoS One, 2014;9(2):e81817.
PMID: 24505241 DOI: 10.1371/journal.pone.0081817

Cholera is a major infectious disease, affecting millions of lives annually. In endemic areas, implementation of vaccination strategy against cholera is vital. As the use of safer live vaccine that can induce protective immunity against Vibrio cholerae O139 infection is a promising approach for immunization, we have designed VCUSM21P, an oral cholera vaccine candidate, which has ctxA that encodes A subunit of ctx and mutated rtxA/C, ace and zot mutations. VCUSM21P was found not to disassemble the actin of HEp2 cells. It colonized the mice intestine approximately 1 log lower than that of the Wild Type (WT) strain obtained from Hospital Universiti Sains Malaysia. In the ileal loop assay, unlike WT challenge, 1×10⁶ and 1×10⁸ colony forming unit (CFU) of VCUSM21P was not reactogenic in non-immunized rabbits. Whereas, the reactogenicity caused by the WT in rabbits immunized with 1×10¹⁰ CFU of VCUSM21P was found to be reduced as evidenced by absence of fluid in loops administered with 1×10²-1×10⁷ CFU of WT. Oral immunization using 1×10¹⁰ CFU of VCUSM21P induced both IgA and IgG against Cholera Toxin (CT) and O139 lipopolysaccharides (LPS). The serum vibriocidal antibody titer had a peak rise of 2560 fold on week 4. Following Removable Intestinal Tie Adult Rabbit Diarrhoea (RITARD) experiment, the non-immunized rabbits were found not to be protected against lethal challenge with 1×10⁹ CFU WT, but 100% of immunized rabbits survived the challenge. In the past eleven years, V. cholerae O139 induced cholera has not been observed. However, attenuated VCUSM21P vaccine could be used for vaccination program against potentially fatal endemic or emerging cholera caused by V. cholerae O139.

Matched MeSH terms: Rabbits
Immunological properties of Hypnale hypnale (hump-nosed pit viper) venom: antibody production with diagnostic and therapeutic potentials

Tan CH, Tan NH, Sim SM, Fung SY, Gnanathasan CA

Acta Trop, 2012 Jun;122(3):267-75.
PMID: 22322247 DOI: 10.1016/j.actatropica.2012.01.016

Envenomation by hump-nosed pit viper (Hypnale hypnale, Hh) in Sri Lanka has caused significant morbidity and mortality, attributed to 35% of total venomous snakebites. In Southwestern India (Kerala), H. hypnale was increasingly identified as a dangerous and common source of envenomation, second to the Russell's viper but ahead of the cobra bites. Unfortunately, there is still no specific antivenom to date. This study aims to investigate the immunological properties of the venom and to assess the feasibility of specific Hh antivenom production as well as the development of a diagnostic assay. Hh venom elicited satisfactory titers of anti-Hh IgG in rabbits after 3rd immunization. The anti-Hh IgG, isolated with caprylic acid precipitation method, was effective in neutralizing the venom lethality (potency=48 LD(50) per ml IgG) as well as its procoagulant, hemorrhagic and necrotic effects, indicating the possibility to produce the specific antivenom using the common immunization regime. Cross-reactivity studies using indirect ELISA showed that anti-Hh IgG cross-reacted extensively with several Asiatic crotalid venoms, particularly that of Calloselasma rhodostoma (73.6%), presumably due to the presence of venom antigens common to both snakes. Levels of immunological cross-reactivity were vastly reduced with double-sandwich ELISA. Further work demonstrated that the assay was able to distinguish and quantify venoms of H. hypnale, Daboia russelii and Echis carinatus sinhaleyus (three common local viperid) used to spike human sera at various concentrations. The assay hence may be a useful investigating tool for diagnosing biting species and studying the time course profile of venom concentrations in blood.

Matched MeSH terms: Rabbits
Treatment outcomes of alginate-embedded allogenic mesenchymal stem cells versus autologous chondrocytes for the repair of focal articular cartilage defects in a rabbit model

Tay LX, Ahmad RE, Dashtdar H, Tay KW, Masjuddin T, Ab-Rahim S, et al.

Am J Sports Med, 2012 Jan;40(1):83-90.
PMID: 21917609 DOI: 10.1177/0363546511420819

Mesenchymal stem cells (MSCs) represent a promising alternative form of cell-based therapy for cartilage injury. However, the capacity of MSCs for chondrogenesis has not been fully explored. In particular, there is presently a lack of studies comparing the effectiveness of MSCs to conventional autologous chondrocyte (autoC) treatment for regeneration of full-thickness cartilage defects in vivo.

Matched MeSH terms: Rabbits
Fulltext Effects of edible bird's nest (EBN) on cultured rabbit corneal keratocytes

Zainal Abidin F, Hui CK, Luan NS, Mohd Ramli ES, Hun LT, Abd Ghafar N

BMC Complement Altern Med, 2011;11:94.
PMID: 21992551 DOI: 10.1186/1472-6882-11-94

There has been no effective treatment or agent that is available for corneal injury in promoting corneal wound healing. Previous studies on edible bird's nest extract (EBN) had reported the presence of hormone-like substance; avian epidermal growth factor that could stimulate cell division and enhance regeneration. This study aimed to investigate the effects of EBN on corneal keratocytes proliferative capacity and phenotypical changes.

Matched MeSH terms: Rabbits
Fulltext Positive outcomes of oil palm phenolics on degenerative diseases in animal models

Sambanthamurthi R, Tan Y, Sundram K, Hayes KC, Abeywardena M, Leow SS, et al.

Br J Nutr, 2011 Dec;106(11):1664-75.
PMID: 21736778 DOI: 10.1017/S0007114511002133

It is well established that plant phenolics elicit various biological activities, with positive effects on health. Palm oil production results in large volumes of aqueous by-products containing phenolics. In the present study, we describe the effects of oil palm phenolics (OPP) on several degenerative conditions using various animal models. OPP reduced blood pressure in a NO-deficient rat model, protected against ischaemia-induced cardiac arrhythmia in rats and reduced plaque formation in rabbits fed an atherogenic diet. In Nile rats, a spontaneous model of the metabolic syndrome and type 2 diabetes, OPP protected against multiple aspects of the syndrome and diabetes progression. In tumour-inoculated mice, OPP protected against cancer progression. Microarray studies on the tumours showed differential transcriptome profiles that suggest anti-tumour molecular mechanisms involved in OPP action. Thus, initial studies suggest that OPP may have potential against several chronic disease outcomes in mammals.

Matched MeSH terms: Rabbits
Expansion and preservation of multipotentiality of rabbit bone-marrow derived mesenchymal stem cells in dextran-based microcarrier spin culture

Boo L, Selvaratnam L, Tai CC, Ahmad TS, Kamarul T

J Mater Sci Mater Med, 2011 May;22(5):1343-56.
PMID: 21461701 DOI: 10.1007/s10856-011-4294-7

The use of mesenchymal stem cells (MSCs) in tissue repair and regeneration despite their multipotentiality has been limited by their cell source quantity and decelerating proliferative yield efficiency. A study was thus undertaken to determine the feasibility of using microcarrier beads in spinner flask cultures for MSCs expansion and compared to that of conventional monolayer cultures and static microcarrier cultures. Isolation and characterization of bone marrow derived MSCs were conducted from six adult New Zealand white rabbits. Analysis of cell morphology on microcarriers and culture plates at different time points (D0, D3, D10, D14) during cell culture were performed using scanning electron microscopy and bright field microscopy. Cell proliferation rates and cell number were measured over a period of 14 days, respectively followed by post-expansion characterization. MTT proliferation assay demonstrated a 3.20 fold increase in cell proliferation rates in MSCs cultured on microcarriers in spinner flask as compared to monolayer cultures (p < 0.05). Cell counts at day 14 were higher in those seeded on stirred microcarrier cultures (6.24 ± 0.0420 cells/ml) × 10(5) as compared to monolayer cultures (0.22 ± 0.004 cells/ml) × 10(5) and static microcarrier cultures (0.20 ± 0.002 cells/ml) × 10(5). Scanning electron microscopy demonstrated an increase in cell colonization of the cells on the microcarriers in stirred cultures. Bead-expanded MSCs were successfully differentiated into osteogenic and chondrogenic lineages. This system offers an improved and efficient alternative for culturing MSCs with preservation to their phenotype and multipotentiality.

Matched MeSH terms: Rabbits
Development of gelatin microspheres loaded with diclofenac sodium for intra-articular administration

Saravanan M, Bhaskar K, Maharajan G, Pillai KS

J Drug Target, 2011 Feb;19(2):96-103.
PMID: 20380621 DOI: 10.3109/10611861003733979

We have previously reported on the targeting of diclofenac sodium in joint inflammation using gelatin magnetic microspheres. To overcome complications in the administration of magnetic microspheres and achieve higher targeting efficiency, the present work focuses on the formulation of gelatin microspheres for intra-articular administration. Drug-loaded microspheres were prepared by the emulsification/cross-linking method, characterized by drug loading, size distribution, scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), X-ray diffraction (XRD), gas chromatography, and in vitro release studies. The targeting efficiency of microspheres was studied in vivo in rabbits. The microspheres showed drug loading of 9.8, 18.3, and 26.7% w/w with an average size range of 37-46 µm, depending upon the drug-polymer ratio. They were spherical in nature and free from surface drug as evidenced by the SEM photographs. FT-IR, DSC, and XRD revealed the absence of drug-polymer interaction and amorphous nature of entrapped drug. Gas chromatography confirms the absences of residual glutaraldehyde. The formulated microspheres could prolong the drug release up to 30 days in vitro. About 81.2 and 43.7% of administered drug in the microspheres were recovered from the target joint after 1 and 7 days of postintra-articular injection, respectively, revealing good targeting efficiency.

Matched MeSH terms: Rabbits
A preliminary study of the effects of glucosamine sulphate and chondroitin sulphate on surgically treated and untreated focal cartilage damage

Kamarul T, Ab-Rahim S, Tumin M, Selvaratnam L, Ahmad TS

Eur Cell Mater, 2011 Mar 15;21:259-71; discussion 270-1.
PMID: 21409755

The effects of Glucosamine Sulphate (GS) and Chondroitin Sulphate (CS) on the healing of damaged and repaired articular cartilage were investigated. This study was conducted using 18 New Zealand white rabbits as experimental models. Focal cartilage defects, surgically created in the medial femoral condyle, were either treated by means of autologous chondrocyte implantation (ACI) or left untreated as controls. Rabbits were then divided into groups which received either GS+/-CS or no pharmacotherapy. Three rabbits from each group were sacrificed at 12 and 24 weeks post-surgery. Knees dissected from rabbits were then evaluated using gross quantification of repair tissue, glycosaminoglycan (GAG) assays, immunoassays and histological assessments. It was observed that, in contrast to untreated sites, surfaces of the ACI-repaired sites appeared smooth and continuous with the surrounding native cartilage. Histological examination demonstrated a typical hyaline cartilage structure; with proteoglycans, type II collagen and GAGs being highly expressed in repair areas. The improved regeneration of these repair sites was also noted to be significant over time (6 months vs. 3 months) and in GS and GS+CS groups compared to the untreated (without pharmacotherapy) group. Combination of ACI and pharmacotherapy (with glucosamine sulphate alone/ or with chondroitin sulphate) may prove beneficial for healing of damaged cartilage, particularly in relation to focal cartilage defects.

Matched MeSH terms: Rabbits
Comparison of histopathological features of Vibrio cholerae O1 El Tor and O139 Bengal infections in rabbit intestinal mucosa

Amin A, Ali A, Kurunathan S, Cheong TG, Al-Jashamy KA, Jaafar H, et al.

Histol Histopathol, 2009 05;24(5):559-65.
PMID: 19283664 DOI: 10.14670/HH-24.559

Vibrio cholerae is the causative agent of the infectious disease, cholera. The bacteria adhere to the mucosal membrane and release cholera toxin, leading to watery diarrhea. There are >100 serovars of V. cholerae, but the O1 and O139 serovars are the main causative agents of cholera. The present study aimed to compare the severity of intestinal mucosal infection caused by O1 El Tor and O139 V. cholerae in a rabbit ileal loop model. The results showed that although the fluid accumulation was similar in the loops inoculated with O1 and O139 V. cholerae, the presence of blood was detected only in the loops inoculated with the O139 serovar. Serosal hemorrhage was confirmed by histopathological examination and the loops inoculated with O139 showed massive destruction of villi and loss of intestinal glands. The submucosa and muscularis mucosa of the ileum showed the presence of edema with congested blood vessels, while severe hemorrhage was seen in the muscularis propria layer. The loops inoculated with O1 El Tor showed only minimal damage, with intact intestinal villi and glands. Diffuse colonies of the O139 serovar were seen to have infiltrated deep into the submucosal layer of the intestine. Although the infection caused by the O1 serovar was focal and invasive, it was more superficial than that due to O139, and involved only the villi. These observations were confirmed by immunostaining with O1 and O139 V. cholerae-specific monoclonal antibodies. The peroxidase reaction demonstrated involvement of tissues down to the submucosal layer in O139 V. cholerae infection, while in O1 El Tor infection, the reaction was confined mainly to the villi, and was greatly reduced in the submucosal region. This is the first reported study to clearly demonstrate the histopathological differences between infections caused by the O139 Bengal and O1 El Tor pathogenic serovars of V. cholerae.

Matched MeSH terms: Rabbits

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