Induction of periodontal disease via retentive ligature, lipopolysaccharide injection, and their combination in a rat model.

Periodontitis is a highly prevalent, chronic immune-inflammatory disease of the periodontium that results in the periodontium and alveolar bone loss's progressive destruction. In this study, the induction of periodontal disease via retentive ligature, lipopolysaccharide, and their combination at three different times were compared in a rat model. Seventy-two Sprague Dawley rats were distributed into four treatment groups: 1) control group with no treatment; 2) application of 4/0 nylon ligature around second maxillary molars; 3) combination of ligature and LPS injection (ligature-LPS); 4) intragingival injection of Porphyromonas gingivalis lipopolysaccharide (Pg-LPS) to the palatal mucosa of the second maxillary molars. Six rats were sacrificed from each group after 7, 14, and 30 days of periodontal disease induction. Alveolar bone loss, attachment loss, number of inflammatory cells, and blood vessels were evaluated histologically. A micro-CT scan was used as a parameter to know the rate of alveolar bone loss. Parametric data were analyzed using two-way ANOVA followed by Bonferroni correction with a significance set at 5%. Non-parametric data were analyzed using Kruskal-Wallis, followed by multiple comparisons with Bonferroni correction. The histological results revealed significant destructive changes in the periodontal tissues and alveolar bone following the ligature and ligature-LPS induction techniques. These changes were evident as early as seven days, maintained until 14 days post-treatment, and declined with time. The ligature technique was effective in inducing acute periodontal disease. The LPS injection technique did not induce alveolar bone loss, and its combination to ligature added insignificant effects.

Detection and distribution of anti-leptospiral antibody among dogs and their handlers.

The incidence of leptospirosis seems to be on the rise and could be an alarming indirect indication of a global re-emergence. It is a potential public health threat when dogs are speculated to be involved in the transmission of leptospirosis through possible subclinical harbouring of Leptospira spp. and subsequent shedding into the environment. This study aimed to detect anti-leptospiral antibodies among dogs and their handlers using the microscopic agglutination test (MAT). Blood samples from 266 apparently healthy dogs and 194 dog handlers were collected at four working dog organisations and four dog shelters. Serum samples were tested using MAT against 20 leptospiral serovars with a cut-off titre >=1:100 (dog) and >=1:50 (dog handlers). Seventy dogs (70/266; 26.3%) were seropositive mainly against serovars Icterohaemorrhagiae, Ballum, Bataviae and Javanica (titres ranged: 1:100-1:800). Sixty-seven dog handlers (67/194; 34.5%) were seropositive mainly against serovars Grippotyphosa, Icterohaemorrhagiae and Malaysia (titres ranged: 1:50-1:200). Dogs were seropositive due to exposure, vaccination or active infection. Seropositive dog handlers could indicate exposure or active infection. This shows the potential of dogs in maintaining and spreading the infection in Malaysia. Due to the occupational risk as a result of frequent contact with dogs and exposure to contaminated environments, dog handlers should be made aware of the presence of this zoonotic disease.

Detection and distribution of anti-leptospiral antibody among dogs and their handlers

@# The incidence of leptospirosis seems to be on the rise and could be an alarming indirect indication of a global re-emergence. It is a potential public health threat when dogs are speculated to be involved in the transmission of leptospirosis through possible subclinical harbouring of Leptospira spp. and subsequent shedding into the environment. This study aimed to detect anti-leptospiral antibodies among dogs and their handlers using the microscopic agglutination test (MAT). Blood samples from 266 apparently healthy dogs and 194 dog handlers were collected at four working dog organisations and four dog shelters. Serum samples were tested using MAT against 20 leptospiral serovars with a cut-off titre >1:100 (dog) and >1:50 (dog handlers). Seventy dogs (70/266; 26.3%) were seropositive mainly against serovars Icterohaemorrhagiae, Ballum, Bataviae and Javanica (titres ranged: 1:100–1:800). Sixty-seven dog handlers (67/194; 34.5%) were seropositive mainly against serovars Grippotyphosa, Icterohaemorrhagiae and Malaysia (titres ranged: 1:50–1:200). Dogs were seropositive due to exposure, vaccination or active infection. Seropositive dog handlers could indicate exposure or active infection. This shows the potential of dogs in maintaining and spreading the infection in Malaysia. Due to the occupational risk as a result of frequent contact with dogs and exposure to contaminated environments, dog handlers should be made aware of the presence of this zoonotic disease.

Aerosolised Mesenchymal Stem Cells Expressing Angiopoietin-1 Enhances Airway Repair.

BACKGROUND: The aim of this study was to investigate the effects of MSCs and MSC-expressing ANGPT1 (MSC-pANGPT1) treatment via aerosolisation in alleviating the asthma-related airway inflammation in the rabbit model. METHODS: Rabbits were sensitised and challenged with both intraperitoneal injection and inhalation of ovalbumin (Ova). MSCs and MSC-pANGPT1 cells were aerosolised into rabbit lungs using the MicroSprayer® Aerosolizer Model IA-1B 48 h after injury. The post mortem was performed 3 days following cell delivery. Histopathological assessments of the lung tissues and inflammatory response were quantitatively scored following treatments. RESULT(S): Administration of aerosolised MSCs and MSC-pANGPT1 were significantly reduced inflammation of the airways (p < 0.001), as reflected by improved of structural changes such as thickness of the basement membrane, epithelium, mucosa and sub-mucosa regions. The airway inflammation score of both treatment groups revealed a significant reduction of inflammation and granulocyte infiltration at the peribronchiale and perivascular regions (p < 0.05). Administration of aerosolised MSCs alone was resulted in significant reduction in the levels of pro-inflammatory genes (IL-4 and TGF-ß) while treatment with aerosolised MSC-pANGPT1 led to further reduction of various pro-inflammatory genes to the base-line values (IL4, TNF, MMP9 and TGF-ß). Treatment with both aerosolised MSCs and MSC-pANGPT1 cells was also alleviated the number of airway inflammatory cells in the bronchoalveolar lavage (BAL) fluid and goblet cell hyperplasia. CONCLUSION(S): Our findings suggest that treatment with MSCs alone attenuated airway inflammation and structural changes of the airway. Treatment with MSC-pANGPT1 provided an additional effect in reducing the expression levels of various pro-inflammatory genes. Both of these treatment enhancing airway repair and therefore may provide a basis for the development of an innovative approach for the treatment and prevention of airway inflammatory diseases.

Seroprevalence of Leptospirosis in Working Dogs.

Working dogs are canine animals that have been trained to assist human beings in carrying out various tasks. They help in guarding property, performing rescues, assisting the visually impaired or physically handicapped, searching for drugs, explosives, and others. Leptospirosis is one of the most widespread zoonotic diseases in the world and a commonly occurring disease of the tropics and subtropics. In Malaysia, all working dogs are normally vaccinated with serovars, Pomona, Icterohaemorrhagiae, Canicola, and Grippotyphosa based on protocols recommended from other countries. The duration of immunity in vaccinated dogs for Leptospira can last up to 13 months; however, there is no full crossprotection between the different serovars. Five representative canine units from different government agencies in Malaysia (n = 96 dogs) were recruited in this study. For detection, the microscopic agglutination test was performed by incubating the serum from dogs with various serovars of leptospires, namely, Icterohaemorrhagiae, Canicola, Pomona, Grippotyphosa, Australis, Bataviae, Javanica, Tarassovi, Hebdomadis, Lai, and Pyrogenes. The plasma obtained was used for polymerase chain reaction (PCR) analysis, for the detection of 16S rRNA, and lipL 32 genes of Leptospira. Out of the 96 dogs sampled, only 3 dogs were positive toward serovars, Australis, Bataviae, and Javanica, based on the cutoff point at 1:80. The seroprevalence of canine leptospirosis in this population was 3.1% (n = 3/96). However, all 96 blood samples of working dogs tested negative for both pathogenic and nonpathogenic Leptospira genes. The results revealed that, by vaccination alone, working dogs were not fully protected against leptospirosis and could pose a risk to dog handlers. A preventative and control protocol for leptospirosis is warranted, and its implementation should be monitored and improved accordingly from time to time, in order to maintain a healthy condition in both working dogs and their handlers.

Prevalence of leptospirosis in healthy dogs and dogs with kidney disease in Klang Valley, Malaysia.

Leptospirosis is under-reported and remarkably neglected in Malaysia, especially in companion animals. In recent years, dogs have become popular pets and potentially act as one of the risk factors for human leptospiral infection. The purpose of this study was to determine the serological and molecular status of leptospirosis in healthy and dogs with kidney disease in Klang Valley, Malaysia and to gain insight of the possible serovars involved in the dog population in Klang Valley, Malaysia. Blood samples were obtained from 57 dogs (19 kidney disease patient; 38 healthy dogs, respectively). Serum samples obtained from these animals were screened for leptospiral antibodies by the microscopic agglutination test (MAT). Polymerase chain reaction (PCR) assay was performed on plasma samples to detect leptospiral DNA. By MAT, three out of 19 (15.8%) dogs with kidney disease were positive for L. canicola. One out of 38 (2.6%) healthy dogs was positive for L. icterohemorrhagiae. The overall seroprevalence for leptospirosis in dogs in Klang Valley, Malaysia was 7.0% (n=4/57). Only one out of the 19 dogs (5.3%) with kidney disease was tested positive to pathogenic Leptospira by PCR assay. All the 38 healthy dogs were negative. Positive results in healthy dogs and dogs with kidney disease for leptospirosis warrant further investigation of leptospirosis in dog population in Malaysia. The prevalence and incidence of this disease in the dog population in this country need further investigation.

Prevalence of leptospirosis in healthy dogs and dogs with kidney disease in Klang Valley, Malaysia

Leptospirosis is under-reported and remarkably neglected in Malaysia, especially in companion animals. In recent years, dogs have become popular pets and potentially act as one of the risk factors for human leptospiral infection. The purpose of this study was to determine the serological and molecular status of leptospirosis in healthy and dogs with kidney disease in Klang Valley, Malaysia and to gain insight of the possible serovars involved in the dog population in Klang Valley, Malaysia. Blood samples were obtained from 57 dogs (19 kidney disease patient; 38 healthy dogs, respectively). Serum samples obtained from these animals were screened for leptospiral antibodies by the microscopic agglutination test (MAT). Polymerase chain reaction (PCR) assay was performed on plasma samples to detect leptospiral DNA. By MAT, three out of 19 (15.8%) dogs with kidney disease were positive for L. canicola. One out of 38 (2.6%) healthy dogs was positive for L. icterohemorrhagiae. The overall seroprevalence for leptospirosis in dogs in Klang Valley, Malaysia was 7.0% (n=4/57). Only one out of the 19 dogs (5.3%) with kidney disease was tested positive to pathogenic Leptospira by PCR assay. All the 38 healthy dogs were negative. Positive results in healthy dogs and dogs with kidney disease for leptospirosis warrant further investigation of leptospirosis in dog population in Malaysia. The prevalence and incidence of this disease in the dog population in this country need further investigation.

Characterization of chitosan-carboxymethyl dextran nanoparticles as a drug carrier and as a stimulator of mouse splenocytes.

The in vitro drug-release behavior of chitosan-carboxymethyl dextran nanoparticles (CDNP) containing cefmetazole, 5-fluorouracil (5-FU) or indocyanine green (ICG), and the in vitro effect of CDNP on mouse B16 melanoma cell proliferation and in vivo modulation effect of CDNP on serum cytokines and spleen lymphocytes in mice were evaluated in this study. Drug-loaded CDNP were prepared by embedding (for cefmetazole or 5-FU) and absorption (for ICG), and the particle size was increased with increased drug association efficiency (AE) and decreased surface amino group content. Prolonged release of cefmetazole (540 min) or 5-FU (360 min) from CDNP was observed when compared to that of nanoparticle-free cefmetazole (210 min) or 5-FU (50 min), and the release of cefmetazole or 5-FU from CDNP98 (CDNP made with 98% degree of deacetylation (DD) chitosan) was slower than from CDNP78 (CDNP made with 78% DD chitosan). High AE (72.0-98.6%), undetectable surface amino group content and dramatically increased particle size (1076.9-1506.0 nm) of ICG-loaded CDNP with undetectable release of ICG within 48 h revealed the good affinity between ICG and CDNP. Twenty-five to 100 µg/ml of CDNP elicited dose-dependent inhibitory effects on B16 tumor cell proliferation, and CDNP98 was more effective than CDNP78. CDNP78 regulated serum IL-17 level in up-regulating IL-4, IL-6, IL-10, IL-23 and TGF-ß within 3 h; on the other hand, CDNP98 significantly down-regulated TGF-ß and had no induction effect on IL-23 within 24 h. In addition, reduced IL-17 was observed in CDNP at 24 h. CDNP98 was more effective than CDNP78 in stimulating mouse splenic T CD4(+), TCD8(+) and NK cell proliferation within 24 h, while CDNP78 was superior to CDNP98 in stimulating B CD19(+) cells. The ability of CDNP to be the drug carrier and to enhance both humoral and cell-mediated immune response in this study demonstrated its promising potential to be applied as biomedical material.