MyMedR

Inhibition of calcium-dependent contractions of the isolated guinea-pig ileal longitudinal muscle and taenia coli by the total glycosidic extract of the plant Sarcolobus globosus

Mustafa MR

Toxicon, 1993 Jan;31(1):67-74.

PMID: 8446965

The effect of the total glysosidic extract of the plant Sarcolobus globosus was investigated on the contractions of the smooth muscle of the guinea-pig ileal longitudinal muscle and taenia coli. In the ileal longitudinal muscle, addition of the extract inhibited the electrical field-stimulated twitches. Similarly to verapamil, it also reduced the contractions of the muscle to acetylcholine, histamine and KCl. However, only the tonic contraction to KCl was reversed by increasing the extracellular calcium concentration. In the taenia coli, lower concentrations of both the extract and verapamil induced a parallel displacement of the dose-response curves to calcium (0.30-30 mM). Addition of the extract also dose-dependently inhibited the KCl-induced contraction of the taenia coli. Increasing the calcium concentration increased the IC50 values of the extract. The result suggests that the inhibitory effect of the Sarcolobus globosus extract on the smooth muscle, like verapamil, is mainly due to inhibition of calcium influx.

Matched MeSH terms: Guinea Pigs

Isolation and PCR detection of rickettsiae from clinical and rodent samples in Malaysia

Tay ST, Rohani MY, Ho TM, Devi S

Southeast Asian J. Trop. Med. Public Health, 2002 Dec;33(4):772-9.

PMID: 12757225

Isolation of rickettsiae from patients' blood samples and organ samples of wild rodents from areas with high seroprevalence of rickettsial infections was attempted using cell culture assay and animal passages. L929 mouse fibroblast cells grown in 24 well tissue culture plate were inoculated with buffy coat of febrile patients and examined for the growth of rickettsiae by Giemsa, Gimenez staining and direct immunofluorescence assay. No rickettsiae were isolated from 48 patients' blood samples. No symptomatic infections were noted in mice or guinea pigs infected with 50 organ samples of wild rodents. There was no rickettsial DNA amplified from these samples using various PCR detection systems for Orientia tsutsugamushi, typhus and spotted fever group rickettsiae.

Matched MeSH terms: Guinea Pigs

Fulltext Adrenoceptor study of guinea-pig superior mesenteric--portal vein

Muir CK, Lim YM

Med J Malaysia, 1980 Jun;34(4):387-90.

PMID: 7219269

The effects of phentolamine and propranolol on contractural responses of guinea-pig superior mesenteric-portal vein to adrenaline and isoprenaline were investigated. Phentolamine was capable of completely abolishing the response to adrenaline and to isoprenaline while propranolol had no effect on responses to either agonist. It is suggested that Alpha receptors are the only type of adrenoceptor involved in adrenergic control of contraction of this vein and that isoprenaline is capable of stimulating these receptors.

Matched MeSH terms: Guinea Pigs

Fulltext Guinea pig inoculation versus culture in the diagnosis of tuberculosis

Cheong YM, Jegathesan M

Med J Malaysia, 1983 Dec;38(4):350.

PMID: 6443797

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

A review of radiation hazards with special reference to diagnostic radiology

Ang AH

Med J Malaysia, 1973 Dec;28(2):75-9.

PMID: 4276302

Matched MeSH terms: Guinea Pigs

Leucocyte alkaline phosphatase, leucocyte count and haemoglobin level in malayan new-borns and young infants

Lie-Injo Luan Eng, Govindasamy S

Med J Malaya, 1965 Jun;19(4):263-6.

PMID: 4220850

Matched MeSH terms: Guinea Pigs

Laboratory observations on the comparative feeding preferences by Aedes schuellaris malayensis from Kuantan and Singapore

Cheong WH

Med J Malaya, 1965 Sep;20(1):73-4.

PMID: 4221430

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

Development of a slide latex agglutination test for rotavirus antigen detection

Yap KL

Malays J Pathol, 1994 Jun;16(1):49-56.

PMID: 16329576

The aim of this study was to optimize the conditions for the passive adsorption of polyclonal antibody onto plain surface polystyrene latex particles and its performance in a slide latex agglutination test for rotavirus antigen detection. Cleaning of latex particles by washing through repetitive centrifuging, decanting and resuspending in distilled water was adequate in removing surfactants from the particles' surfaces to enable coating. A study of antibody concentration, incubation temperature and buffer pH revealed that optimum coating was achieved with a 3-fold excess of antibody to the calculated total particle surface capacity for the antibody in a glycine-saline buffer of pH 9.2 at 40 degrees C for 4 hours. The ionic strength and pH of the latex suspending buffer and the sample buffer were critical factors determining the sensitivity of the test and the appearance of non-specific agglutination. Ultrasonication, addition of glycerol and Tween 20, either individually or in combination, were able to suppress non-specific agglutination in some batches of latex reagents. Polyethylene glycol 6000 enhanced the quality of agglutination as well as reduced the time of its appearance, especially in reagents that produced poor agglutination.

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

Isolation and characterization of the major phospholipase A2 from the venom of Trimeresurus purpureomaculatus (shore pit viper)

Nget Hong Tan, Chon Seng Tan, Hun Teck Khor

Int. J. Biochem., 1989;21(12):1421-6.

PMID: 2612728

1. The major phospholipase A2 (PLA-DE4) of the venom of Trimeresurus purpureomaculatus (shore pit viper) has been purified to electrophoretic homogeneity. 2. The isoelectric point of the purified enzyme was determined to be 4.20, and the mol. wt was 31,700 as estimated by Sephadex G-75 gel filtration chromatography; and 14,000 as estimated by SDS-polyacrylamide gel electrophoresis. The purified enzyme hydrolyzed phosphatidylcholine (PC) faster than phosphatidylethanolamine (PE), whereas phosphatidylserine (PS) was not hydrolyzed at all (PC greater than PE greater than PS =0). However, in reaction system consisted of mixtures of PC and PS, phosphatidylserine was effectively hydrolyzed by the enzyme. 4. The phospholipase A2 exhibited edema-forming activity but not hemolytic, hemorrhagic or anticoagulant activities. It was not lethal to mice at a dosage of 10 micrograms/g by i.v. route.

Matched MeSH terms: Guinea Pigs

Fulltext Advances & challenges in leptospiral vaccine development

Bashiru G, Bahaman AR

Indian J Med Res, 2018 Jan;147(1):15-22.

PMID: 29749356 DOI: 10.4103/ijmr.IJMR_1022_16

Considerable progress has been made in the field of leptospiral vaccines development since its first use as a killed vaccine in guinea pigs. Despite the fact that the immunity conferred is restricted to serovars with closely related lipopolysaccharide antigen, certain vaccines have remained useful, especially in endemic regions, for the protection of high-risk individuals. Other conventional vaccines such as the live-attenuated vaccine and lipopolysaccharide (LPS) vaccine have not gained popularity due to the reactive response that follows their administration and the lack of understanding of the pathogenesis of leptospirosis. With the recent breakthrough and availability of complete genome sequences of Leptospira, development of novel vaccine including recombinant protein vaccine using reverse vaccinology approaches has yielded encouraging results. However, factors hindering the development of effective leptospiral vaccines include variation in serovar distribution from region to region, establishment of renal carrier status following vaccination and determination of the dose and endpoint titres acceptable as definitive indicators of protective immunity. In this review, advancements and progress made in LPS-based vaccines, killed- and live-attenuated vaccines, recombinant peptide vaccines and DNA vaccines against leptospirosis are highlighted.

Matched MeSH terms: Guinea Pigs

A Malaysian experience with animal disease

Little PB

Can. Vet. J., 1979 Jan;20(1):13-21.

PMID: 761153

The report summarizes a one year period of investigation of death losses in West Malaysian livestock. Lesions and etiological agents are mentioned for cattle, sheep, goats, swine, poultry and companion animals as well as some miscellaneous species. Special observations related to a common paramphistome induced hepatic biliary infestation in cattle, a serious malignant head catarrh outbreak in which possible cattle to cow aerosol transmission occurred. Trismus observed in some cattle with malignant head catarrh was associated with arteriolitis and ganglioneuritis of the V cranial nerve. Parasitic, bacterial, viral toxic and neoplastic diseases are recorded in the various species. The occurrence of fatal chronic fluorosis in laboratory guinea pigs and cerebral nematodiasis in a Thoroughbred racehorse are documented.

Matched MeSH terms: Guinea Pigs

Characterization of the possible mechanisms underlying the hypotensive and spasmogenic effects of Loranthus ferrugineus methanolic extract

Ameer OZ, Salman IM, Siddiqui MJ, Yam MF, Sriramaneni RN, Sadikun A, et al.

Am J Chin Med, 2009;37(5):991-1008.

PMID: 19885958

In the present study, L. ferrugineus methanol extract (LFME) was evaluated for its blood pressure lowering effect in anesthetized normotensive Sprague Dawley (SD) rats and its spasmogenic effect in isolated guinea pig ileum. The possible mechanism(s) of action were also investigated. LFME was obtained by Soxhlet extraction. The rats were fasted overnight and anesthetized with sodium pentobarbitone (60 mg/kg i.p.). LFME was administered in i.v. boluses in the concentrations of 25, 50, 100 and 200 mg/kg respectively, with concomitant monitoring of mean arterial pressure (MAP). It was found that LFME dose-dependently reduced MAP. An i.v. bolus injection of atropine significantly decreased the blood pressure lowering effect of LFME. Similarly, L-NAME (Nomega-nitro-L-arginine methyl ester) significantly lowered both the MAP and the action duration. Conversely, no significant change in MAP was seen following i.v. injections of neostigmine, hexamethonium, prazosin and propranolol. LFME also produced a dose-dependent contractile effect in guinea pig ileum. This contraction was significantly reduced in atropine pre-incubated tissue segments, yet it was significantly enhanced in the presence of neostigmine. No appreciable change in the ability of LFME to contract guinea pig ileum was seen in the presence of hexamethonium. Accordingly, it can be postulated that LFME possesses a marked hypotensive effect that can be attributed to stimulation of muscarinic receptors and/or stimulation of nitric oxide (NO) release. Moreover, LFME retains a considerable spasmogenic action due to its cholinergic properties. The hypotensive and spasmogenic effects of LFME justify its traditional uses.

Matched MeSH terms: Guinea Pigs

Fulltext Effects of Garcinia atroviridis on serum profiles and atherosclerotic lesions in the aorta of guinea pigs fed a high cholesterol diet

Amran AA, Zaiton Z, Faizah O, Morat P

Singapore Med J, 2009 Mar;50(3):295-9.

PMID: 19352574

The fruit extract of Garcinia atroviridis (G. atroviridis) contains hydroxycitric acid and flavonoids, which have been reported to have a hypolipidaemic property. This extract with solvent methanol was used to investigate its effects on serum lipid profiles of guinea pigs fed a high cholesterol diet.

Matched MeSH terms: Guinea Pigs

Hendra virus disease in horses

Westbury HA

Rev. - Off. Int. Epizoot., 2000 Apr;19(1):151-9.

PMID: 11189712

The author provides an account of the discovery of a previously undescribed disease of horses and a description of the studies involved in determining the aetiology of the disease. The causative virus, now named Hendra virus (HeV), is the reference virus for a proposed new genus within the virus family Paramyxoviridae. The virus is a lethal zoonotic agent able to cause natural disease in humans and horses and experimentally induced disease in cats, guinea-pigs and mice. The virus also naturally infects species of the family Megachiroptera, mainly subclinically, and such animals are the natural host of HeV. The virus appears to transmit readily between species of Megachiroptera, but not readily between horses under natural and experimental conditions, or from horses to humans. The method of transmission from bats to horses is not known. Three incidents of HeV disease in horses have been recorded in Australia--two in 1994 which caused the death of two humans and fifteen horses and one in 1999 which involved the death of a single horse. Hendra virus is related to Nipah virus, the virus that caused disease and mortality in humans, pigs, dogs and cats in Malaysia during 1998 and 1999.

Matched MeSH terms: Guinea Pigs

Influence of indomethacin on histamine- and acetylcholine-induced responses in the intact and denuded epithelium of guinea pig tracheal smooth muscle

Akbar A, Sharma JN

Pharmacol Res, 1992 Apr;25(3):279-86.

PMID: 1518772

We have investigated the effect of indomethacin on histamine- and acetylcholine (ACh)-induced responses in the intact and denuded epithelium of guinea pig isolated tracheal smooth muscle. Epithelium removal resulted in increased responsiveness to ACh and histamine. Indomethacin (2.8 microM) enhanced the sensitivity of both intact and denuded preparations to histamine and ACh. These findings suggest that the tracheal epithelium of guinea pig plays a protective role against bronchoconstrictors, such as ACh and histamine. Furthermore, indomethacin-mediated hyperresponsiveness caused by these agonists in epithelium denuded preparations might be a reflection of removal of prostaglandin (PG) biosynthesis. A similar process of interaction in indomethacin-treated asthmatic patients (with damaged airway epithelium) might take place. The significance of these findings is discussed.

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

Alteration in apyrase enzyme attenuated virulence of Shigella flexneri

BangaSingh KK, Nisha M, Lau HY, Ravichandran M, Salleh MZ

Microb Pathog, 2016 Feb;91:123-8.

PMID: 26706344 DOI: 10.1016/j.micpath.2015.12.004

Virulence of Shigella is attributed to the genes presence in chromosome or in the megaplasmid. The apy gene which is located in the megaplasmid of Shigella species encodes for apyrase enzyme, a pathogenesis-associated enzyme causing mitochondrial damage and host cell death. In this study we constructed an apy mutant of Shigella flexneri by insertional activation using a kanamycin resistant gene cassette. The wild type apy gene of S. flexneri 2a was PCR amplified, cloned and mutated with insertion of kanamycin resistant gene cassette (aphA). The mutated construct (apy: aphA) was subcloned into a conjugative suicidal vector (pWM91) at the unique Sma1 and Sac1 sites. The mutation of the wild apy gene in the construct was confirmed by DNA sequencing. The mutated construct was introduced into wild type S. flexneri 2a by conjugation with Escherichia coli. After undergoing homologous recombination, the wild apy gene was deleted from the construct using the sucrose selection method. Non-functional activity of the apyrase enzyme in the constructed strain by colorimetric test indicated the successful mutation of the apyrase enzyme. This strain with mutated apy gene was evaluated for its protective efficacy using the guinea pig keratoconjunctivitis model. The strain was Sereny negative and it elicited a significant protection following challenge with wild S. flexneri strain. This apy mutant strain will form a base for the development of a vaccine target for shigellosis.

Matched MeSH terms: Guinea Pigs

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