12 research outputs found

    Driving forces for changes in geographic range of cattle ticks (Acari: Ixodidae) in Africa: A review

    Get PDF
    Ticks are the most important external parasites of cattle and are known to transmit more pathogens than any other group of arthropods worldwide. About 80% of the world cattle population is at risk of ticks and tick-borne diseases, causing a global annual loss of $US22–30 billion. In Africa, the impact of ticks is ranked high, and they transmit diseases such as cowdriosis, anaplasmosis, bovine babesiosis and theileriosis. A range expansion of ixodid ticks has been observed in Africa, in particular for the genera Amblyomma and Rhipicephalus, which contribute greatly to cattle loss owing to morbidity and mortality. Distributional changes in ticks can lead to the emergence or re-emergence of infectious and parasitic diseases. Climate change is frequently invoked as the primary cause of tick distribution, but it is not the only factor. Human lifestyle changes, including transportation of livestock within countries, have promoted the introduction of new tick species and the diseases they transmit. One such example is the spread of the Asian cattle tick Rhipicephalus (Boophilus) microplus to West Africa. Rhipicephalus (Boophilus) microplus was recorded for the first time in Namibia and was probably introduced into Namibia from South Africa. Likewise, Amblyomma variegatum, the vector of heartwater disease, has the largest distribution in Africa. Its spread is outside its native range and it is considered the second most invasive tick species after R. (B.) microplus on the continent. Rhipicephalus (Boophilus) microplus is a one-host tick that is reported to be resistant to conventional acaricides and this contributes largely to its spread into non-endemic areas.Keywords: Acaricide resistance, climate change, epidemiology, range expansion, tick ecolog

    T-Cell Receptor Beta Variable Gene Polymorphism Predicts Immune-Related adverse Events During Checkpoint Blockade Immunotherapy

    Get PDF
    BACKGROUND: Immune checkpoint inhibitors have revolutionized cancer treatment. However, they are associated with a unique spectrum of side effects, called immune-related adverse events (irAEs), which can cause significant morbidity and quickly progress to severe or life-threatening events if not treated promptly. Identifying predictive biomarkers for irAEs before immunotherapy initiation is therefore a critical area of research. Polymorphisms within the T-cell receptor beta (TCRB) variable (TRBV) gene have been implicated in autoimmune disease and may be mechanistically linked to irAEs. However, the repetitive nature of the TCRB locus and incomplete genome assembly has hampered the evaluation of TRBV polymorphisms in the past. PATIENTS AND METHODS: We used a novel method for long-amplicon next generation sequencing of rearranged TCRB chains from peripheral blood total RNA to evaluate the link between TRBV polymorphisms and irAEs in patients treated with immunotherapy for cancer. We employed multiplex PCR to create amplicons spanning the three beta chain complementarity-determining regions (CDR) regions to enable detection of polymorphism within the germline-encoded framework and CDR1 and CDR2 regions in addition to CDR3 profiling. Resultant amplicons were sequenced via the Ion torrent and TRBV allele profiles constructed for each individual was correlated with irAE annotations to identify haplotypes associated with severe irAEs (≥ grade 3). RESULTS: Our study included 81 patients who had irAEs when treated with immunotherapy for cancer. By using principal component analysis of the 81 TRBV allele profiles followed by k-means clustering, we identified six major TRBV haplotypes. Strikingly, we found that one-third of this cohort possessed a TRBV allele haplotype that appeared to be protective against severe irAEs. CONCLUSION: The data suggest that long-amplicon TCRB repertoire sequencing can potentially identify TRBV haplotype groups that correlate with the risk of severe irAEs. Germline-encoded TRBV polymorphisms may serve as a predictive biomarker of severe irAEs

    Relationship between Post-Traumatic Stress Disorder and Social Adjustment among Students of College of Education Gidanwaya Kaduna State, Nigeria

    No full text
    This study examined the Relationship between Post-Traumatic Stress Disorder, Social Adjustment among Students of College of Education Gidan Waya Kaduna State. Three objectives were formulated to guide the study. The study adopted a correlational research design. The target population of the study were four hundred and eleven (411) among Students of College of Education Gidan Waya Kaduna State. The sample of the study were 196 participants drawn from NCEII students. Data was collected using post-traumatic stress disorder inventory (PTSDI) by Harvard refuge trauma adapted from educational media solution, social adjustment inventory (SAI) by Bell. Post-traumatic stress disorder inventory (PSDI) faced and content was validated and had the reliability of .856 also social adjustment has a reliability of .898 respectively after pilot testing. The collected data was processed and analyzed using descriptive (frequencies, mean and standard deviation) and inferential statistics Pearson Product Moment Correlation (r). All tests were done at 0.05 alpha level of significance. The finding shows that a relationship exists between anxiety and the social adjustment of college students (r=-0.681, p=0.001). Aggression and social adjustment of college students (r=-0.770, p=0.000). Depression and Social adjustment of College students (r=-0.795, p=0.000). From the results of the findings it was recommended among others that Conference/workshop should be organized for the Teachers, administrators, in order to pay more attention to College students with Post-Traumatic Disorder issues and refer them to psychological testing and counselling centres by adopting this, will improve the social adjustment of college students. Since there is a relationship between anxiety and social adjustment psychologists and counsellors should be encouraged in addressing students with anxiety problems thereby having functional psychological testing and counselling centres for proper social adjustmen

    T-cell receptor beta variable gene polymorphism predicts immune-related adverse events during checkpoint blockade immunotherapy

    No full text
    Background Immune checkpoint inhibitors have revolutionized cancer treatment. However, they are associated with a unique spectrum of side effects, called immune-related adverse events (irAEs), which can cause significant morbidity and quickly progress to severe or life-threatening events if not treated promptly. Identifying predictive biomarkers for irAEs before immunotherapy initiation is therefore a critical area of research. Polymorphisms within the T-cell receptor beta (TCRB) variable (TRBV) gene have been implicated in autoimmune disease and may be mechanistically linked to irAEs. However, the repetitive nature of the TCRB locus and incomplete genome assembly has hampered the evaluation of TRBV polymorphisms in the past.Patients and methods We used a novel method for long-amplicon next generation sequencing of rearranged TCRB chains from peripheral blood total RNA to evaluate the link between TRBV polymorphisms and irAEs in patients treated with immunotherapy for cancer. We employed multiplex PCR to create amplicons spanning the three beta chain complementarity-determining regions (CDR) regions to enable detection of polymorphism within the germline-encoded framework and CDR1 and CDR2 regions in addition to CDR3 profiling. Resultant amplicons were sequenced via the Ion Torrent and TRBV allele profiles constructed for each individual was correlated with irAE annotations to identify haplotypes associated with severe irAEs (≥ grade 3).Results Our study included 81 patients who had irAEs when treated with immunotherapy for cancer. By using principal component analysis of the 81 TRBV allele profiles followed by k-means clustering, we identified six major TRBV haplotypes. Strikingly, we found that one-third of this cohort possessed a TRBV allele haplotype that appeared to be protective against severe irAEs.Conclusion The data suggest that long-amplicon TCRB repertoire sequencing can potentially identify TRBV haplotype groups that correlate with the risk of severe irAEs. Germline-encoded TRBV polymorphisms may serve as a predictive biomarker of severe irAEs
    corecore