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The protective action of piperlongumine against mycobacterial pulmonary tuberculosis in its mitigation of inflammation and macrophage infiltration in male BALB/c mice
2021
Lu Nihong | Yang Yongrui | Li Xiaofei | Li Jie | Cheng Jie | Lv Zhengxuan | Du Yingrong
Piperlongumine (PL) is a bioactive alkaloid and medicinal compound of piperamide isolated from the long pepper (Piper longum Linn). It has demonstrated bactericidal action against Mycobacterium tuberculosis (MTB), the cause of pulmonary tuberculosis; nevertheless, immunomodulatory activity had not been identified for it in MTB-triggered granulomatous inflammation. This study investigated if piperlongumine could inhibit such inflammation.
Afficher plus [+] Moins [-]Tuberculosis cross-species transmission in Tanzania: Towards a One-Health concept
2012
Erasto V. Mbugi | Bugwesa Z. Katale | Sharon Kendall | Liam Good | Gibson S. Kibiki | Julius D. Keyyu | Peter Godfrey-Faussett | Paul van Helden | Mecky I. Matee
For centuries, tuberculosis, which is a chronic infection caused by the bacillus <em>Mycobacterium tuberculosis</em> has remained a global health problem. The global burden of tuberculosis has increased, particularly in the Southern African region, mainly due to HIV, and inadequate health systems which has in turn given rise to emergent drug resistant tuberculosis (TB) strains. Bovine tuberculosis (BTB) has also emerged as a significant disease with the tendency for inter-species spread. The extent of interspecies BTB transmission both in urban and rural communities has not been adequately assessed. The phenomenon is of particular importance in rural communities where people share habitats with livestock and wildlife (particularly in areas near national parks and game reserves). Aerosol and oral intake are the major routes of transmission from diseased to healthy individuals, with health care workers often contracting infection nosocomially. Although TB control has increasingly been achieved in high-income countries, the disease, like other poverty-related infections, has continued to be a disaster in countries with low income economies. Transmission of infections occurs not only amongst humans but also between animals and humans (and occasionally vice versa) necessitating assessment of the extent of transmission at their interface. This review explores tuberculosis as a disease of humans which can cross-transmit between humans, livestock and wildlife. The review also addresses issues underlying the use of molecular biology, genetic sequencing and bioinformatics as t tools to understand the extent of inter-species cross-transmission of TB in a ‘One Health’ context.
Afficher plus [+] Moins [-]Epidemiology and microscopic diagnosis of tuberculosis in pigs and small ruminants slaughtered at Bobo-Dioulasso abattoir, Burkina Faso
2021
Adama Sanou | Amadou Dicko | Kadiatou R. Sow | Arthur Djibougou | Antoinette Kabore | Bassirou Diarra | Arsène K. Ouedraogo | Dezemon Zingue | Moumini Nouctara | Zekiba Tarnagda
Bovine tuberculosis (bTB) is a zoonotic, infectious, chronic and contagious disease, caused by Mycobacterium bovis that mainly affects cattle. This pathology has a negative impact on animals and animal products trade. Unfortunately, in Burkina Faso where agriculture and livestock sectors represent around 80% of the socio-economic activities, the real situation of the disease is not well known especially in small ruminants and swine. Thus, our study focused on both the epidemiology and the microbiological diagnosis of tuberculosis (TB) in small ruminants and pigs slaughtered at Bobo-Dioulasso abattoir. A prospective study was conducted between August 2017 and December 2017. Epidemiological data collection was performed during routine meat inspection; moreover, samples were taken and transported to the Bacteriology laboratory of Centre Muraz for microbiological analyses. This diagnosis consisted in search of Acid Fast Bacilli (AFB) using the hot Ziehl–Neelsen staining. Out of a total of 14 648 small ruminants and 2430 pigs slaughtered during the study period, 156 and 17 had lesions suggestive of bTB with prevalence of 1.07% and 0.7%, respectively. Females and those between 2 and 4 years old were mainly infected. The most affected organs were: lungs, liver, spleen and lymph nodes. Finally, microscopy revealed 43.35% (75/173) of positive cases for AFB. These results confirm the presence of bTB in small ruminants and pigs in Burkina Faso. Efforts must still be made in the fight against this zoonosis in order to limit its economic and public health impacts.
Afficher plus [+] Moins [-]Comparison between tuberculin test results and ELISA for diagnosis of bovine tuberculosis
2007
F. R. El-Seedy | Sohair S. Elyas | W.H. Hassan | E. A. Nasr
A total of 300 cross-bred dairy cattle in Beni-Suef and El-Fayoum Governorates were screened for bovine tuberculosis using single intradermal (SID) cervical tuberculin test. 18 out of 300 (6%) tested cattle were found tuberculin positive. Blood samples from the positive reactors were tested by ELISA. ELISA plates were coated by either bovine purified protein derivative (PPD) or short term culture filtrate (ST-CF) antigens. The test sensitivity was compared at different serum dilutions. At serum dilution of 1/40, all of the 18 tuberculin positive samples, (100%), were ELISA positive using both ST-CF and PPD antigens, but at 1/80 dilution, 13 (72.22%) and 12 (66.66%) samples; at 1/160, 11 (61.11%) and 11 (61.11%) and finally at 1/320, 10 (55.55%) and 9 (50%) were ELISA positive on using ST-CF and PPD as a coating antigens respectively
Afficher plus [+] Moins [-]The protective action of piperlongumine against mycobacterial pulmonary tuberculosis in its mitigation of inflammation and macrophage infiltration in male BALB/c mice
2021
Lu, Nihong | Yang, Yongrui | Li, Xiaofei | Li, Jie | Cheng, Jie | Lv, Zhengxuan | Du, Yingrong
Piperlongumine (PL) is a bioactive alkaloid and medicinal compound of piperamide isolated from the long pepper (Piper longum Linn). It has demonstrated bactericidal action against Mycobacterium tuberculosis (MTB), the cause of pulmonary tuberculosis; nevertheless, immunomodulatory activity had not been identified for it in MTB-triggered granulomatous inflammation. This study investigated if piperlongumine could inhibit such inflammation. Mycobacterium tuberculosis strain H37Rv was subjected to a broth microdilution assay. Piperlongumine at 5, 15, and 25 μg/mL, 0.2% dimethyl sulphoxide as control or 4 μM of dexamethasone were tested in vitro on MH-S murine alveolar macrophages. BALB/c mice were orally administered PL at 50, 100 and 150 mg/kg b.w. after trehalose-6,6-dimycolate (TDM) stimulation. Chemokine and cytokine concentrations were determined in lung supernatants. Flow cytometry and Western blot analysis were performed to determine phosphorylated spleen tyrosine kinase (Syk), c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) pathways. Piperlongumine inhibited inflammatory mediators and adherence of lymphocyte function-associated antigen 1 to MH-S cells following TDM activation. It also improved macrophage clearance of MTB. In TDM-stimulated MH-S cells, PL significantly influenced the macrophage inducible Ca²⁺-dependent lectin receptor (Mincle)-Syk-ERK signalling pathway. Oral dosing of PL effectively suppressed the development of pulmonary granulomas and inflammatory reactions in the TDM-elicited mouse granuloma model. PL as an inhibitor of MTB-triggered granulomatous inflammation may be an effective complementary treatment for mycobacterial infection.
Afficher plus [+] Moins [-]Performance of ESAT-6 for serodiagnosis of nonhuman primate tuberculosis: A meta-analysis
2015
Fangui Min | Jing Wang | Yu Zhang
ESAT-6 is one of the most studied antigens in vaccine, diagnosis, and pathogenic mechanism of tuberculosis. In the present study, a meta-analysis was performed regarding the use of ESAT-6 based antibody detection test for diagnosing nonhuman primate (NHP) tuberculosis. Studies in English and Chinese were searched and selected strictly. Quality of included studies was assessed using the standardized QUADAS-2 tool. Heterogeneity was explored through meta-regression. Finally, eight studies were included with high degree of homogeneity. Quality of included studies was general satisfied except the bias of “patient selection” for the majority of serum samples were from experimental infections. Estimates of sensitivity ranged from 69% to 82%, while specificity ranged from 96% to 99%. Area under ROC curves and Q were 0.9503 and 0.8909 respectively, indicating a high diagnostic accuracy. Current evidence suggests that ESAT-6 based serodiagnosis has the potential to become useful diagnostic tools for NHP tuberculosis.
Afficher plus [+] Moins [-]Zoonotic diseases diagnosed from Jan 2016 to Aug 2017 in Regional Veterinary Laboratories, Department of Veterinary Services, Malaysia
2018
Zulkifli A. | Santhi M. | Marzuki Z. | Rohana A. B. | Norasyikin A. | Tariq J. | Chandrawathani P. | Saira Banu M. R. | Faizah Hanim M. S.
Infectious diseases of livestockare a major threat to global animal health and welfare and their effective control is crucialfor agronomic health, for safeguarding and securing national and international food supplies and for alleviating rural povertyin developing countries. Some devastating livestock diseases are endemic in many parts of the world and threats from old and new pathogens continue to emerge, with changes to global climate, agricultural practices and demography presenting conditions that are especially favourable for the spread of arthropod-borne diseases into new geographical areas. Zoonotic infections that are transmissible either directly or indirectly between animals and humans are on the increase and pose significant additional threats to human health and the current pandemic status of new influenza A (H1N1) is a topical example of the challenge presented by zoonotic viruses (Tomley and Shirley, 2009). Malaysia, being one of the members of the World Organisation forAnimal Health (OIE) which is responsible for setting standards for control of animal diseases. For year 2017, the list included 116 animal diseases, infections and infestations, many of which are zoonotic in nature. As such, this paper discusses the commonzoonotic infections diagnosed in the five Regional Veterinary Laboratories which are spread across the country and entrustedto carry out diagnostic tests to aid in the treatment and control of animal diseases. A total of almost half a million samples weretested comprising more than a million tests to help the Department of Veterinary Services control and eradicate economically important diseases to safeguard the animal population. Of these, zoonotic diseases comprise a small but significant entity which needs careful attention (Chandrawathani et al., 2017) Dora Tan (1981) reported that among the many zoonotic diseases prevalent in Malaysia, are leptospirosis, rabies, influenza, Japanese encephalitis, toxoplasmosis,ornithosis, Q fever and monkeypox which have been investigated at the lnstitute for Medical Research, Kuala Lumpur. The regional laboratories have full capability to conduct tests to confirm parasitic, viral and bacterial infections except for rabies andavian influenza, which was diagnosed in the Veterinary Research Institute. However, preliminary tests for avian influenza wascarried out in regional laboratories.
Afficher plus [+] Moins [-]Evaluation of pathogen-specific biomarkers for the diagnosis of tuberculosis in white-tailed deer (Odocoileus virginianus)
2017
Wanzala, Sylvia I. | Palmer, Mitchell V. | Waters, Wade R. | Thacker, Tyler C. | Carstensen, Michelle | Travis, Dominic A. | Sreevatsan, Srinard
OBJECTIVE To develop a noninvasive biomarker-based detection system specific for Mycobacterium bovis for monitoring infection in wild animals. SAMPLE Serum samples from 8 experimentally infected yearling white-tailed deer (Odocoileus virginianus) and 3 age-matched control deer and from 393 Minnesota Department of Natural Resources hunter-harvested white-tailed deer in northwest Minnesota. PROCEDURES 8 yearling deer were inoculated with 2 × 10(8) CFUs of virulent M bovis strain 1315 (day 0), and sera were obtained on days 0, 19, 48, and 60; sera were obtained from 3 uninoculated control deer on those same days. Sera from these deer and 9 M bovis-positive hunter-harvested deer were tested for 3 Mycobacterium-specific biomarkers (MB1895c, MB2515c, and polyketide synthase 5) by use of an indirect ELISA. That same ELISA was used to test sera obtained from 384 exposed noninfected deer in northwest Minnesota from 2007 through 2010, concurrent with an outbreak of tuberculosis involving cattle and deer in that region. RESULTS ELISA results revealed that tuberculosis infection could be detected as early as 48 days after inoculation in experimentally infected deer. Results for 384 deer sera revealed that prevalence of tuberculosis decreased over the 4-year period. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the prevalence of tuberculosis in Minnesota deer decreased after 2009 but tuberculosis may have persisted (as subclinical disease) at extremely low levels, as indicated by the presence of low concentrations of circulating biomarkers. Biomarker-based diagnostic tests may offer a specific approach for early identification of M bovis infection.
Afficher plus [+] Moins [-]Surveillance for Mycobacterium bovis transmission from domestic cattle to wild ruminants in a Mexican wildlife-livestock interface area
2012
Objective: To assess the prevalence of Mycobacterium bovis infection in cattle and wild ruminants (WRs) in a wildlife-livestock interface area (WLIA) of the Mexican highland plateau. Animals: 24,400 cattle from 793 herds (including 17,351 commercially slaughtered cattle) and 142 WRs (110 white-tailed deer [Odocoileus virginianus], 20 red deer [Cervus elaphus], and 12 North American elk [Cervus canadensis]) harvested via controlled hunting. Procedures: Cattle were serially tested for M bovis infection via caudal fold tuberculin and comparative cervical tuberculin tests during field surveillance. Carcasses of cattle and WRs were inspected for gross lesions; samples suggestive of tuberculosis were analyzed via histologic evaluation and mycobacterial culture (HMC). A PCR assay to detect Mycobacterium tuberculosis complex organisms was performed to confirm positive results of HMC. Results: WRs had inflammatory lesions in lungs and lymph nodes, although HMC results did not indicate M bovis infection. Eight cattle had positive results for both tuberculin tests, and 31 had positive results for HMC of grossly detected lesions; all were from 7 herds, and ≥ 1 cow in each herd had positive PCR assay results. These 7 herds were depopulated; adjacent herds and herds related via commerce were quarantined. Calculated true prevalence of M bovis infection was 0.86% (95% confidence interval, 0.24% to 1.49%) in cattle; M bovis was not detected in any WRs. Conclusions and Clinical Relevance: M bovis infection was present in cattle. Although transmission to WRs in this WLIA was not detected, diagnosis and prevention activities should be implemented and consolidated to prevent potential M bovis transmission between cattle and WRs.
Afficher plus [+] Moins [-]Epidemiologic investigation of Mycobacterium bovis in a population of cats
2002
Kaneene, John B. | Bruning-Fann, Colleen S. | Dunn, John | Mullaney, Thomas P. | Berry, Dale | Massey, Jeffrey P. | Thoen, Charles O. | Halstead, Steven | Schwartz, Kathy
Objective-To determine whether cats exposed at a residence were infected with Mycobacterium bovis, whether the tuberculin skin test can identify cats infected with M bovis, and whether an ELISA could identify tuberculosis-infected cats. Animals-20 domestic cats exposed to a cat with laboratory-confirmed disseminated M bovis infection. Procedure-Cats were administered a tuberculin skin test and monitored for 72 hours. Blood and fecal samples were collected. Cats were then euthanatized, and postmortem examinations were performed. Tissues were examined grossly and histologically for signs of mycobacteriosis. Pooled tissue samples and fecal samples were submitted for mycobacterial culture. Blood samples were examined for evidence of tuberculosis by use of a comparative ELISA. Results-4 cats had positive responses for the ELISA, and 2 cats had suspicious responses. All tuberculin skin tests yielded negative results. No gross or histologic lesions of tuberculosis were detected in any tissues, and mycobacteria were not isolated from tissues or feces obtained from the 20 cats. Conclusions and Clinical Relevance-All cats that had positive or suspicious responses for the ELISA were offspring of the cat with tuberculosis. Evidence of tuberculosis was not seen in other cats at the residence, the owner, or the attending veterinarian. The most likely source of tuberculosis for the infected cat was through the consumption of M bovis-infected wildlife carcasses or offal. Because M bovis is endemic in wildlife in northeastern Michigan, there is a risk of exposure to tuberculosis in companion animals, their owners, and attending veterinarians.
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