First detection of Toxoplasma gondii Africa 4 lineage in a population of carnivores from South Africa

Introduction

There have only been a few molecular studies conducted on the detection of T. gondii in tissues of carnivores in South Africa, with no data on the genetic diversity of this parasite. That is why the aim of this study was to detect and genotype T. gondii DNA in tissues of selected wild and domestic carnivores in South Africa.

Methods

Samples were collected from 80 animals of 20 species (mainly road-killed) in the four provinces of Limpopo (n=57), Mpumalanga (n=21), Gauteng (n=1) and Free State (n=1) during the period 2014-2018. Samples of brain (n=31), heart (n=4), liver (n=40), spleen (n=2) and lung (n=3) were used to detect T. gondii by real-time PCR targeting a 529 bp repeating fragment of T. gondii DNA. Samples that were positive in real-time PCR were genotyped using 15 microsatellite markers.

Results

T. gondii DNA was detected in 4 (5 %) samples: in the brain from a Black-backed Jackal (Canis mesomelas), in the liver from a African Wildcat (Felis silvestris lybica) and in the liver and heart of two Rusty-spotted Genets (Genetta maculata) respectively. The DNA sample from Black-backed Jackal was genotyped and characterized as belonging to the type Africa 4 lineage (equivalent to RFLP genotype ToxoDB#20), that is a widespread lineage in Africa.

Discussion

This is the first genetic characterization of T. gondii isolated from a wild carnivore on the African continent and the first report of T. gondii in Black-backed Jackal. The Africa 4 lineage was also confirmed in the region of Southern Africa for the first time.

Molecular tracking and prevalence of the red colour morph restricted to a harvested leopard population in South Africa

The red leopard (Panthera pardus) colour morph is a colour variant that occurs only in South Africa, where it is confined to the Central Bushveld bioregion. Red leopards have been spreading over the past 40 years, which raises the speculation that the prevalence of this phenotype is related to low dispersal of young individuals owing to high off‐take in the region. Intensive selective hunting tends to remove large resident male leopards from the breeding population, which gives young male leopards the chance to mate with resident female leopards that are more likely to be their relatives, eventually increasing the frequency of rare genetic variants. To investigate the genetic mechanisms underlying the red coat colour morph in leopards, and whether its prevalence in South Africa relates to an increase in genetic relatedness in the population, we sequenced exons of six coat colour‐associated genes and 20 microsatellite loci in twenty Wild‐type and four red leopards. The results were combined with demographic data available from our study sites. We found that red leopards own a haplotype in homozygosity identified by two SNPs and a 1 bp deletion that causes a frameshift in the tyrosinase‐related protein 1 (TYRP1), a gene known to be involved in the biosynthesis of melanin. Microsatellite analyses indicate clear signs of a population bottleneck and a relatedness of 0.11 among all pairwise relationships, eventually supporting our hypothesis that a rare colour morph in the wild has increased its local frequency due to low natal dispersal, while subject to high human‐induced mortality rate.

[Outcome of tunneled hemodialysis catheters as permanent vascular access]

Tunneled cuffed hemodialysis catheters (THC) are developed as a means of short hemodialysis access while a more permanent form of access are maturing. The aim of this study is to investigate the effectiveness, survival and complications of the THC used for long-term vascular access.

METHODS

In a retrospective study we looked at 42 THC inserted between November 2000 and October 2003, in 40 elderly patients, with systemic disease or when other vascular access was not possible.

RESULTS

Procedural complications occurred in 5 cases (11.9%), which included: local haemorrhage (3), hemothorax (1) and one fatal venous tear. 6 catheters (14.2%) were removed due to complications (non-function 3 and bacteraemia 3). The total incidence of THC related infections was 0.18 episodes/1,000 catheters-days. Patients were followed up for a mean 379 days (range 1-1,140) and a total of 15,946 catheter-days. Qb and KT/V achieved at one month were 278.3 +/- 34.1 ml/min and 1.48 +/- 0.27 respectively. At the end of the follow-up, 23 patients (54.7%) were alive with catheter functioning. One, three and twelve months survival was 90.4%, 73.1% and 59.5% respectively.

CONCLUSION

The THC may be a useful alternative permanent vascular access for hemodialysis patients when others vascular access are not possible.

[Metabolic markers of chronic liver disease]

The association between chronic liver disease and plasmatic lipids and glucidic metabolism was studied. The liver was evaluated with biochemical variables, ultrasound and upper gastrointestinal endoscopy. 12 chronic liver diseases patients and 10 normal were studied. 83.3% of patients showed lipidic abnormalities, 66.6% on the cholesterol levels and 41.7%, reduced HDL. When patients received 100 gr of glucose the response was abnormal in 83.3%. These results were compared with other "liver function test". 75% had abnormal bilirubin, 58.3% abnormal albumin, prothrombin time 58.3%, aminotransferases 75%. Esophageal verices were found in 75% of cases and ultrasound abnormalities in 91.6% (27.3% cirrhosis, 54.4% diffuse abnormal patter and 18.2% splenomegaly). These findings show that lipidic and glucidic metabolism, and ultrasound, in chronic liver diseases are the more frequent abnormalities.

[Epidemiology of viral hepatitis in Venezuela: preliminary results of phase 1. Prevalence in the metropolitan area]

Two different areas of metropolitan zone in Venezuela were studied in relationship to the immunological condition associated with A, B, C and D viral hepatitis in 557 healthy subjects. We performed clinical history with personal information, that was subsequently correlated with results of the hepatitis markers. General results show prevalence different from previous reports: Anti-HAV: 90.84%, HBsAg: 1.62%, Anti-HBc: 10.6%, Anti-HCV: 0.36% y Anti HDV: 0%.