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Fulltext Pathogenicity of leptospira icterohaemorrhagiae serovar lai strain Langkawi in guinea pigs (cavia porcellus)

Tyagita, H., Bahaman, A.R., Jasni, S., Ibrahim, T.A.T., Fuzina, N.H.

Jurnal Veterinar Malaysia, 2019;31(1):1-11.
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A tourist was infected with a new strain of leptospires namely, Leptospira icterohemorrhagiae serovar Lai strain Langkawi, when he was on vacation in Langkawi, Malaysia. The leptospiral strain was successfully isolated from the patient in the Netherland. In this study, the bacteria were retrieved from Holland and inoculated into fifteen guinea pigs in Universiti Putra Malaysia (UPM) to determine its pathogenicity. The main clinical symptoms in the guinea pigs were decreased appetite and jaundice. Blood profile showed high neutrophil, lymphocyte, PCV, RBC, haemoglobin, leukocyte and thrombocyte counts. Besides that, enhancement of electrolytes such as sodium (Na), chloride (Cl), and potassium (K) was also noted. Biochemical examination showed an increase alkaline phosphatase (ALP), aspartate transaminase (AST) and bilirubin levels. Albumin, alanine transaminase (ALT), blood urea, total protein and creatinine were low values. Histopathological examination under haematoxylin and eosin staining showed evidence of haemorrhages, congestion and oedema in all organs, with inflammatory cell infiltration characterized by neutrophils, lymphocytes and macrophages. Hydropic degeneration and cell necrosis were also common in the findings. Leptospires were detected from Day 2 p.i by silver staining and transmission electron microscopy (TEM). Rise in antibody titre was seen as early as Day 5 p.i and leptospiral DNA was detected by PCR in the kidneys and liver on Day 3 and Day 5, respectively. The findings were indicative of leptospirosis. This study demonstrated that guinea pigs are a suitable animal model to illustrate the clinical symptoms and pathological changes seen following infection with Leptospira icterohaemorrhagiae serovar Lai strain Langkawi. In general, the symptoms and changes seen in leptospirosis are similar to viral infections and the information and data from this present study would help differentiate infection due to leptospires from that of viral infection. Leptospiral infection has often been misdiagnosed to be viral infection such as influenza and dengue which have similar signs and symptoms as leptospirosis.

Matched MeSH terms: Guinea Pigs
Pigmentation and dermal conservative effects of the astonishing algae Sargassum polycystum and Padina tenuis on guinea pigs, human epidermal melanocytes (HEM) and Chang cells

Quah CC, Kim KH, Lau MS, Kim WR, Cheah SH, Gundamaraju R

Afr J Tradit Complement Altern Med, 2014;11(4):77-83.
PMID: 25392585

BACKGROUND: The preference for a fairer skin-tone has become a common trend among both men and women around the world. In this study, seaweeds Sargassum polycystum and Padina tenuis were investigated for their in vitro and in vivo potentials in working as skin whitening agents. Seaweed has been used as a revolutionary skin repairing agent in both traditional and modern preparations. The high antioxidant content is one of the prime reasons for its potent action. It has been employed in traditional Chinese and Japanese medicine. For centuries, most medical practitioners in the Asian cultures have known seaweed as an organic source of vitamins, minerals, fatty acids like omega-3 and omega-6 and antioxidants. The present objective of the study was to evaluate the potent dermal protective effect of the two seaweeds Sargassum polycystum and Padina tenuis on human cell lines and guinea pigs.
MATERIAL AND METHODS: Seaweeds were extracted with ethanol and further fractionated with hexane, ethyl acetate and water. The extracts were tested for mushroom tyrosinase inhibitory activity, cytotoxicity in human epidermal melanocyte (HEM), and Chang cells. Extracts with potent melanocytotoxicity were formulated into cosmetic cream and tested on guinea pigs in dermal irritation tests and de-pigmentation assessments.
RESULTS: Both Sargassum polycystum and Padina tenuis seaweeds showed significant inhibitory effect on mushroom tyrosinase in the concentration tested. SPEt showed most potent cytotoxicity on HEM (IC50 of 36µg/ml), followed by SPHF (65µg/ml), and PTHF (78.5µg/ml). SPHF and SPEt reduced melanin content in skin of guinea pigs when assessed histologically.
CONCLUSION: SPEt, SPHF and PTHF were able to inhibit HEM proliferation in vitro, with SPHF being most potent and did not cause any dermal irritation in guinea pigs. The results obtained indicate that SPHF is a promising pharmacological or cosmetic agent.

Matched MeSH terms: Guinea Pigs
Possible virulence factors involved in bacteraemia caused by Aeromonas hydrophila

Vadivelu J, Puthucheary SD, Phipps M, Chee YW

J Med Microbiol, 1995 Mar;42(3):171-4.
PMID: 7884797

Eighteen strains of Aeromonas hydrophila from patients with bacteraemia were investigated for possible virulence factors. Cytotoxin and haemolysin were produced by all strains, whereas cholera toxin-like factor was produced by 33% of strains only. Enterotoxin production was not detected. Haemagglutination of guinea-pig, fowl and rabbit erythrocytes was demonstrated by 83%, 67% and 61% of strains, respectively. Fucose- and mannose-sensitive haemagglutinins were predominant. None of the strains agglutinated sheep erythrocytes. Extrachromosomal DNA was detected in 17 strains, 16 of which had a plasmid (3.6-5.1 MDa), the majority being between 4.6 and 5.1 MDa.

Matched MeSH terms: Guinea Pigs
Potentiation of bradykinin-induced responses by indomethacin in the intact and denuded epithelium of guinea pig tracheal preparations

Akbar A, Sharma JN, Yusof AP, Gan EK

Int J Tissue React, 1998;20(3):95-100.
PMID: 9894182

We studied the effect of indomethacin, a cyclooxygenase inhibitor, on bradykinin-induced responses in the intact and denuded epithelium of the isolated tracheal smooth muscle in guinea pigs. Epithelium removal alone did not alter the responsiveness to bradykinin. Indomethacin (2.8 microM) enhanced the sensitivity to bradykinin of both intact and denuded preparations. This finding suggests that the tracheal epithelial may have no protective effect on the contractile responses induced by bradykinin. This may be due to the presence of high amounts of bradykinin-inactivating enzymes in the tracheal smooth muscle. Indomethacin-medicated potentiation caused by bradykinin in epithelium intact and denuded preparations may be an indication of removal of the bronchodilator prostaglandin biosynthesis. The significance of these findings is discussed.

Matched MeSH terms: Guinea Pigs
Radioactive uptake of [14C]histamine by certain tissues in guinea-pigs treated and untreated with chlorpromazine

Ridzwan BH, Waton NG

Comp Biochem Physiol C Comp Pharmacol Toxicol, 1990;97(2):251-5.
PMID: 1982867

1. Oral administration of [14C]histamine induced the presence of small amounts of [14C]histamine in stomach and ileal tissues of control guinea-pigs. In contrast, much larger amounts were found after 8 h infusion. 2. Similar amounts of [14C]histamine were found in the tissues when [14C]histamine was given by intravenous infusion from 24-30 h after chlorpromazine injection.

Matched MeSH terms: Guinea Pigs
Review of the complications in peritoneal dialysis

Mukherjee AP

Med J Malaya, 1969 Sep;24(1):21-3.
PMID: 4243838
Matched MeSH terms: Guinea Pigs
SRJ23, a new semisynthetic andrographolide derivative: in vitro growth inhibition and mechanisms of cell cycle arrest and apoptosis in prostate cancer cells

Wong HC, Wong CC, Sagineedu SR, Loke SC, Lajis NH, Stanslas J

Cell Biol Toxicol, 2014 Oct;30(5):269-88.
PMID: 25070834 DOI: 10.1007/s10565-014-9282-5

3,19-(3-Chloro-4-fluorobenzylidene)andrographolide (SRJ23), a new semisynthetic derivative of andrographolide (AGP), exhibited selectivity against prostate cancer cells in the US National Cancer Institute (NCI) in vitro anti-cancer screen. Herein, we report the in vitro growth inhibition and mechanisms of cell cycle arrest and apoptosis induced by SRJ23.

Matched MeSH terms: Guinea Pigs
Safety and efficacy of dermal fibroblast conditioned medium (DFCM) fortified collagen hydrogel as acellular 3D skin patch

Maarof M, Mh Busra MF, Lokanathan Y, Bt Hj Idrus R, Rajab NF, Chowdhury SR

Drug Deliv Transl Res, 2019 02;9(1):144-161.
PMID: 30547385 DOI: 10.1007/s13346-018-00612-z

Skin substitutes are one of the main treatments for skin loss, and a skin substitute that is readily available would be the best treatment option. However, most cell-based skin substitutes require long production times, and therefore, patients endure long waiting times. The proteins secreted from the cells and tissues play vital roles in promoting wound healing. Thus, we aimed to develop an acellular three-dimensional (3D) skin patch with dermal fibroblast conditioned medium (DFCM) and collagen hydrogel for immediate treatment of skin loss. Fibroblasts from human skin samples were cultured using serum-free keratinocyte-specific media (KM1 or KM2) and serum-free fibroblast-specific medium (FM) to obtain DFCM-KM1, DFCM-KM2, and DFCM-FM, respectively. The acellular 3D skin patch was soft, semi-solid, and translucent. Collagen mixed with DFCM-KM1 and DFCM-KM2 showed higher protein release compared to collagen plus DFCM-FM. In vitro and in vivo testing revealed that DFCM and collagen hydrogel did not induce an immune response. The implantation of the 3D skin patch with or without DFCM on the dorsum of BALB/c mice demonstrated a significantly faster healing rate compared to the no-treatment group 7 days after implantation, and all groups had complete re-epithelialization at day 17. Histological analysis confirmed the structure and integrity of the regenerated skin, with positive expression of cytokeratin 14 and type I collagen in the epidermal and dermal layer, respectively. These findings highlight the possibility of using fibroblast secretory factors together with collagen hydrogel in an acellular 3D skin patch that can be used allogeneically for immediate treatment of full-thickness skin loss.

Matched MeSH terms: Guinea Pigs
Fulltext Survival and Intra-Nuclear Trafficking of Burkholderia pseudomallei: Strategies of Evasion from Immune Surveillance?

Vadivelu J, Vellasamy KM, Thimma J, Mariappan V, Kang WT, Choh LC, et al.

PLoS Negl Trop Dis, 2017 01;11(1):e0005241.
PMID: 28045926 DOI: 10.1371/journal.pntd.0005241

BACKGROUND: During infection, successful bacterial clearance is achieved via the host immune system acting in conjunction with appropriate antibiotic therapy. However, it still remains a tip of the iceberg as to where persistent pathogens namely, Burkholderia pseudomallei (B. pseudomallei) reside/hide to escape from host immune sensors and antimicrobial pressure.
METHODS: We used transmission electron microscopy (TEM) to investigate post-mortem tissue sections of patients with clinical melioidosis to identify the localisation of a recently identified gut microbiome, B. pseudomallei within host cells. The intranuclear presence of B. pseudomallei was confirmed using transmission electron microscopy (TEM) of experimentally infected guinea pig spleen tissues and Live Z-stack, and ImageJ analysis of fluorescence microscopy analysis of in vitro infection of A549 human lung epithelial cells.
RESULTS: TEM investigations revealed intranuclear localization of B. pseudomallei in cells of infected human lung and guinea pig spleen tissues. We also found that B. pseudomallei induced actin polymerization following infection of A549 human lung epithelial cells. Infected A549 lung epithelial cells using 3D-Laser scanning confocal microscopy (LSCM) and immunofluorescence microscopy confirmed the intranuclear localization of B. pseudomallei.
CONCLUSION: B. pseudomallei was found within the nuclear compartment of host cells. The nucleus may play a role as an occult or transient niche for persistence of intracellular pathogens, potentially leading to recurrrent episodes or recrudescence of infection.

Matched MeSH terms: Guinea Pigs
The PPARgamma coding region and its role in visceral obesity

Boon Yin K, Najimudin N, Muhammad TS

Biochem Biophys Res Commun, 2008 Jun 27;371(2):177-9.
PMID: 18413145 DOI: 10.1016/j.bbrc.2008.04.013

Peroxisome proliferator-activated receptor gamma (PPARgamma) is a ligand activated transcription factor, plays many essential roles of biological function in higher organisms. The PPARgamma is mainly expressed in adipose tissue. It regulates the transcriptional activity of genes by binding with other transcription factor. The PPARgamma coding region has been found to be closest to that of monkey in ours and other research groups. Thus, monkey is a more suitable animal model for future PPARgamma studying, although mice and rat are frequently being used. The PPARgamma is involved in regulating alterations of adipose tissue masses result from changes in mature adipocyte size and/or number through a complex interplay process called adipogenesis. However, the role of PPARgamma in negatively regulating the process of adipogenesis remains unclear. This review may help we investigate the differential expression of key transcription factor in adipose tissue in response to visceral obesity-induced diet in vivo. The study may also provide valuable information to define a more appropriate physiological condition in adipogenesis which may help to prevent diseases cause by negative regulation of the transcription factors in adipose tissue.

Matched MeSH terms: Guinea Pigs
The antiscorbutic activity of dehydroascorbic acid

Leong PC

Journal of the Malaya Branch of the British Medical Association, 1939;3:228-37.

Matched MeSH terms: Guinea Pigs
The depletion effects of chlorpromazine, reserpine and ascorbic acid on tissue histamine of guinea-pigs

Ridzwan BH, Jais AM, Waton NG

Gen. Pharmacol., 1988;19(4):631-6.
PMID: 3410287

1. 30 mg kg-1 chlorpromazine (CPZ) depleted more than half of the tissue histamine from lungs, stomach, ileum and skin of the normal guinea-pigs. However, the drug increased the tissue histamine content in scorbutic animals. 2. In contrast, reserpine depleted histamine from the four tested tissues in both normal and scorbutic animals, except those in the lungs of the control animals. 3. Ascorbic acid only depleted histamine from the stomach and ileum. 4. A 24 hr period was the time limit for CPZ to deplete the histamine in all the four tested tissues. 5. Histamine partially or completely recovered in the tissues after the next 24 hr.

Matched MeSH terms: Guinea Pigs
The first isolate of Mycoplasma pneumoniae in Malaysia

Cheong YM, Jegathesan M, Singh M, Wong S, Ong L

Malays J Pathol, 1985 Aug;7:51-2.
PMID: 3939616
Matched MeSH terms: Guinea Pigs
The nonlinear elastic and viscoelastic passive properties of left ventricular papillary muscle of a guinea pig heart

Hassan MA, Hamdi M, Noma A

J Mech Behav Biomed Mater, 2012 Jan;5(1):99-109.
PMID: 22100084 DOI: 10.1016/j.jmbbm.2011.08.011

The mechanical behavior of the heart muscle tissues is the central problem in finite element simulation of the heart contraction, excitation propagation and development of an artificial heart. Nonlinear elastic and viscoelastic passive material properties of the left ventricular papillary muscle of a guinea pig heart were determined based on in-vitro precise uniaxial and relaxation tests. The nonlinear elastic behavior was modeled by a hypoelastic model and different hyperelastic strain energy functions such as Ogden and Mooney-Rivlin. Nonlinear least square fitting and constrained optimization were conducted under MATLAB and MSC.MARC in order to obtain the model material parameters. The experimental tensile data was used to get the nonlinear elastic mechanical behavior of the heart muscle. However, stress relaxation data was used to determine the relaxation behavior as well as viscosity of the tissues. Viscohyperelastic behavior was constructed by a multiplicative decomposition of a standard Ogden strain energy function, W, for instantaneous deformation and a relaxation function, R(t), in a Prony series form. The study reveals that hypoelastic and hyperelastic (Ogden) models fit the tissue mechanical behaviors well and can be safely used for heart mechanics simulation. Since the characteristic relaxation time (900 s) of heart muscle tissues is very large compared with the actual time of heart beating cycle (800 ms), the effect of viscosity can be reasonably ignored. The amount and type of experimental data has a strong effect on the Ogden parameters. The in vitro passive mechanical properties are good initial values to start running the biosimulation codes for heart mechanics. However, an optimization algorithm is developed, based on clinical intact heart measurements, to estimate and re-correct the material parameters in order to get the in vivo mechanical properties, needed for very accurate bio-simulation and for the development of new materials for the artificial heart.

Matched MeSH terms: Guinea Pigs
The role of cyclic AMP and cyclic GMP in mitogen induced cell proliferation in leukocytes

Chiew GS

Med J Malaysia, 1979 Dec;34(2):187-92.
PMID: 232900
Matched MeSH terms: Guinea Pigs
The typhus group of diseases in Malaya. Part I: The study of the virus of rural typhus in laboratory animals. Part II: The study of the virus of tsutsugamushi disease in laboratory animals

Lewthwaite R, Savoor SR

Br J Exp Pathol, 1936;17:1-20.

1. A strain of the rural form of tropical typhus has been established and maintained in guinea-pigs, and is now in its 97th generation. The history and characteristics of this strain are given. The clinical criterion of infection is a well-marked febrile reaction. Scrotal swelling does not occur. Ascites invariably follows intra-peritoneal inoculation of passage virus.
2. In more than one hundred other such attempts made in this laboratory it has proved impossible to maintain a strain beyond a few generations. Similarly all attempts to maintain the virus of the tsutsugamushi disease in guinea-pigs have failed. The guinea-pig must, therefore, be regarded as very insusceptible to the viruses of the rural typhus and tsutsugamushi group of fevers of Malaya.
3. Infection of rabbits by the intra-ocular inoculation of the virus of rural typhus and of the tsutsugamushi disease has been readily secured. The method, based on that of Nagayo et al., and the criteria of infection, are described in detail.
4. The white rat is readily infected with the virus of rural typhus, the infection being of the "inapparente" form. That the virus could be maintained with unabated virulence for 21 generations indicates, by the criterion of Nicolle, that rural typhus is a murine strain.
5. Monkeys have been successfully infected by the intradermal route with the virus of rural typhus and of the tsutsugamushi disease. At the sites of inoculation, in the case of both viruses, necrotic ulcers have developed that appear to be identical with one another, and with the initial lesion of the tsutsugamushi disease in man; in all other features the experimental infections in the monkey appear to be identical. Rabbits have been similarly infected.
6. The results of the Weil-Felix reactions of sera from rabbits and monkeys convalescent from experimental infection with rural typhus and the tsutsugamushi disease are summarized.
7. Methods of demonstration of Rickettsia from infected guinea-pigs and rabbits are described. In morphology, distribution and staining characteristics the Rickettsia demonstrable in material from animals infected with rural typhus and with the tsutsugamushi disease are identical, and do not appear to differ from the Rickettsia orientalis of Nagayo.
8. The experimental data secured indicate that, provided that intra-ocular inoculation is practised, the rabbit is the laboratory animal of choice in the case of the rural typhus and tsutsugamushi group of fevers (it being assumed that
expense and scarcity make extensive use of monkeys impracticable). Further, these data stress the remarkable similarity of the behaviour of these two viruses in experimental laboratory animals-a similarity that, as will be set forth in a later paper, is fully supported by cross-immunity experiments.

Matched MeSH terms: Guinea Pigs
The typhus group of diseases in Malaya. Part III: The study of the virus of the urban typhus in laboratory animals

Lewthwaite R, Savoor SR

Br J Exp Pathol, 1936;17:23-34.

1. A strain of the urban form of tropical typhus has been established in guinea-pigs, and maintained in them for more than one hundred generations. The history and characteristics of the strain are given. The clinical criteria of infection are febrile and scrotal reactions.
2. Methods of demonstration of Rickettsia in material from infected guinea-pigs and rabbits are described. In morphology, distribution and staining characteristics these Rickettsia do not appear to differ from R. prowazeki.
3. The infection of rabbits by intra-ocular inoculation of virus has met with only partial success ; the strains rapidly lose virulence, and do not survive beyond the third generation. The results are closely similar to those reported by Nagayo et al., in corresponding infections of rabbits with the virus of typhus exanthematicus, and to those obtained by the authors in corresponding infections with a strain of Rocky Mountain spotted fever.
4. Infection of white rats has been readily secured, and has been of the "inapparente" form.
5. Two monkeys, inoculated intradermally with infected material, showed a mild general reaction only; no lesion developed at the site of inoculation.
6. The results of the Weil-Felix reactions of sera from rabbits and monkeys convalescent from the infection are summarized. Agglutination is of the OX19 type of Proteus X strains, never of the OXK type.
7. The experimental data obtained indicate that the guinea-pig is the laboratory animal of choice for the study of the urban form of tropical typhus.

Matched MeSH terms: Guinea Pigs
The typhus group of diseases in Malaya. Part IV: The isolation of two strains of tropical typhus from wild rats

Lewthwaite R, Savoor SR

Br J Exp Pathol, 1936;17:208.

(1) Two strains of tropical typhus have been isolated from wild rats trapped in endemic areas.
(2) Both were isolated and maintained in guinea-pigs.
(3) One could be isolated in rabbits by the intra-ocular inoculation of virus, and maintained thus indefinitely. The features of this infection appeared to be identical with corresponding infections obtained with the viruses of rural typhus and the tsutsugamushi disease of human origin. Repeated attempts to isolate the other rat strain in rabbits in the same manner failed.
(4) Rickettsia were found with ease and in abundance in infected material from guinea-pigs infected with either strain, and from rabbits infected with the one-strain.
(5) The sera of rabbits infected with the two rat strains gave positive Weil-Felix reactions of significant titre.
(6) Cross-immunity tests in rabbits between one rat strain and six strains of huinan origin of rural typhus and tsutsugamushi showed a cross-immunity to exist, complete in five strains and partial in the sixth strain.
(7) A concomitant infection with sodoku was present in the guinea-pigs of botlh strains ; although this may have modified the clinical signs, the infection by a typhus virus could be determined by four decisive criteria.
(8) The conclusion is drawn that the murine origin of the virus of the rural typhus-tsutsugamuslhi group of diseases is now firmly established.

Matched MeSH terms: Guinea Pigs
The typhus group of diseases in Malaya. Part VI: The search for carriers

Lewthwaite R, Hodgkin EP, Savoor SR

Br J Exp Pathol, 1936;17:309-17.

1. Transmission of the virus of urban typhus under experimental conditions from rat to rat by the rat flea (X. cheopis) by feeding has been effected. Collateral attempts to transmit the virus of rural typhus by precisely the same procedure failed.
2. Transmission of the virus of urban typhus was also achieved by the inoculation of faeces or crushed tissue of infected fleas into the scarified skin of guinea-pigs.
3. Multiplication of the virus of urban typhus occurs within the rat flea.
4. Infection with the virus of urban typhus is not hereditary in the rat flea.
5. Attempts to transmit the virus of urban or rural typhus by two species of ticks failed. In the case of rural typhus a lessened mortality in the experimental guinea-pigs following test inoculation with passage virus makes it, however, difficult to exclude ticks entirely as a minor factor in the epidemiology of rural typhus.

Matched MeSH terms: Guinea Pigs
The typhus group of diseases in Malaya. Part VII: The relation of rural typhus to the tsutsugamushi disease (with special reference to cross-immunity tests)

Lewthwaite R, Savoor SR

Br J Exp Pathol, 1936;17:448-60.

1. Cross-immunity tests between strains of rural typhus and tsutsugamushi in the guinea-pig, rabbit and monkey were made. Complete cross-immunity between the strains was demonstrated.
2. The problem of the absence of a primary ulcer in rural typhus and its presence in tsutsugamushi is discussed. Experimental findings are recorded; from consideration of these and certain clinical and epidemiological observations, the conclusion is drawn that one and the same virus may cause gradations of dermal lesion that vary greatly in extent and duration.
3. Correlation of the results of cross-immunity tests and experimental infections with clinical, aetiological, epidemiological and serological findings indicates that the two diseases are identical. Rural typhus is not a disease sui generis, and the term should be discarded, the older designation, "tsutsugamushi disease ", being retained.

Matched MeSH terms: Guinea Pigs

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