Blastocystis sp. is a unicellular parasitic microorganism commonly found in the gastrointestinal tracts of humans and animals. It causes symptomatic or asymptomatic infection and its route of transmission is via fecal-oral. High prevalence of Blastocystis infection in developing countries is usually due to poor hygiene practices, exposure to animals infected with the parasite and intake of contaminated water or food. Blastocystis infected individuals often suffer from diarrhea, abdominal pain, nausea, and stomach bloating. Even though pathogenicity of Blastocystis is unclear, it is commonly associated with irritable bowel syndrome. In this review, we have analysed the evidence that shows the association between this microorganism and gastrointestinal disorders. There have been a number of studies which showed that the pathogenicity of Blastocystis is related to its different STs. The pathogenicity is speculated to be due to cysteine proteases formation which stimulates mucosal cells to release interleukin-8 which has been associated with extreme dehydration and gut inflammation. In vitro studies on human colonic epithelial cells revealed that incubation of Blastocystis modulated the host immune response by stimulating the formation of pro-inflammatory cytokines and granulocyte macrophage colonystimulating factor. Metronidazole is found to be the first-line drug of choice. Another treatment option is the combination therapy with trimethoprim/sulfamethoxazole.
Inflammatory gastrointestinal (GI) diseases and malignancies are associated with growing morbidity and cancer-related mortality worldwide. GI tumor and inflammatory cells contain activated sphingolipid-metabolizing enzymes, including sphingosine kinase 1 (SphK1) and SphK2, that generate sphingosine-1-phosphate (S1P), a highly bioactive compound. Many inflammatory responses, including lymphocyte trafficking, are directed by circulatory S1P, present in high concentrations in both the plasma and the lymph of cancer patients. High fat and sugar diet, disbalanced intestinal flora, and obesity have recently been linked to activation of inflammation and SphK/S1P/S1P receptor (S1PR) signaling in various GI pathologies, including cancer. SphK1 overexpression and activation facilitate and enhance the development and progression of esophageal, gastric, and colon cancers. SphK/S1P axis, a mediator of inflammation in the tumor microenvironment, has recently been defined as a target for the treatment of GI disease states, including inflammatory bowel disease and colitis. Several SphK1 inhibitors and S1PR antagonists have been developed as novel anti-inflammatory and anticancer agents. In this review, we analyze the mechanisms of SphK/S1P signaling in GI tissues and critically appraise recent studies on the role of SphK/S1P/S1PR in inflammatory GI disorders and cancers. The potential role of SphK/S1PR inhibitors in the prevention and treatment of inflammation-mediated GI diseases, including GI cancer, is also evaluated.
OBJECTIVE: IVIG is known to confer significant benefit in rheumatologic conditions, including inflammatory myopathy. This study aimed to assess the efficacy of IVIG across different aspects of internal organ involvement in refractory active SSc, particularly the gastrointestinal (GI) system.
METHODS: SSc patients with overlap polymyositis who remained active and unresponsive to conventional disease-modifying agents and who subsequently received IVIG were identified. GI symptoms were assessed using validated questionnaires. The Medical Research Council Sum Score for muscle strength and modified Rodnan skin score (mRSS) were assessed. Serial measurements were undertaken at baseline prior to the first IVIG treatment and post-treatment in the most recent assessment.
RESULTS: Fifteen SSc patients were consecutively recruited into this observational study. The mean duration of IVIG treatment was 2.3 years, with treatment frequency ranging from every 6 weeks to 4 months. Compared with baseline, there was a significant reduction in gastro-oesophageal reflux frequency and intensity mean scores (P = 0.006 and P = 0.013, respectively). Significant improvement in the Gastrointestinal Tract (GIT) 2.0 score from a baseline mean score of 1.07 (s.d. 0.67) to 0.60 (0.46) (P = 0.002) was observed. There was regression in the markers of muscle disease with a reduction in the mean (s.d.) Medical Research Council sum score and the median creatine kinase level (P = 0.001 and P = 0.025, respectively). Significant amelioration of the mean basal modified Rodnan skin score from 21.5 (s.d. 13.8) to 10 (10.6) (P = 0.005) was observed.
CONCLUSION: IVIG may be a helpful adjunctive therapy in the amelioration of some key clinical aspects in refractory SSc. Sustained benefit from IVIG suggests a specific immunomodulatory effect on those with established SSc GI complications.
Study site: Royal Free Hospital, United Kingdom
Haemonchosis is a common problem on goat farms in tropical countries such as Malaysia. Prevention of production losses generally depends on the use of anthelmintic drugs, but is threatened by the emergence of anthelmintic resistance. This study investigates anthelmintic efficacy on small-scale Malaysian goat farms and describes putative risk factors. Adult goats had moderate to high pre-treatment faecal trichostrongyle egg counts, despite being housed on slatted floors and fed on cut-and-carry forage, raising questions about the source of nematode infection. Our results show multiple resistance to benzimidazole and macrocyclic lactone anthelmintic drugs and allow us to discuss the genetic origins of resistance with reference to farm husbandry and management. We conclude that improvement in Malaysian goat production efficiency will require the development of sustainable helminth control strategies, underpinned by a better understanding of the origins and population genetics of anthelmintic resistance.