59 research outputs found
Inflammatory Cytokine Expression Is Associated with Chikungunya Virus Resolution and Symptom Severity
The Chikungunya virus infection zones have now quickly spread from Africa to parts of Asia, North America and Europe. Originally thought to trigger a disease of only mild symptoms, recently Chikungunya virus caused large-scale fatalities and widespread economic loss that was linked to recent virus genetic mutation and evolution. Due to the paucity of information on Chikungunya immunological progression, we investigated the serum levels of 13 cytokines/chemokines during the acute phase of Chikungunya disease and 6- and 12-month post-infection follow-up from patients of the Italian outbreak. We found that CXCL9/MIG, CCL2/MCP-1, IL-6 and CXCL10/IP-10 were significantly raised in the acute phase compared to follow-up samples. Furthermore, IL-1β, TNF-α, Il-12, IL-10, IFN-γ and IL-5 had low initial acute phase levels that significantly increased at later time points. Analysis of symptom severity showed association with CXCL9/MIG, CXCL10/IP-10 and IgG levels. These data give insight into Chikungunya disease establishment and subsequent convalescence, which is imperative to the treatment and containment of this quickly evolving and frequently re-emerging disease
Climatic and topographic changes since the Miocene influenced the diversification and biogeography of the tent tortoise (Psammobates tentorius) species complex in Southern Africa
Background: Climatic and topographic changes function as key drivers in shaping genetic structure and cladogenic
radiation in many organisms. Southern Africa has an exceptionally diverse tortoise fauna, harbouring one-third of
the world’s tortoise genera. The distribution of Psammobates tentorius (Kuhl, 1820) covers two of the 25 biodiversity
hotspots in the world, the Succulent Karoo and Cape Floristic Region. The highly diverged P. tentorius represents an
excellent model species for exploring biogeographic and radiation patterns of reptiles in Southern Africa.
Results: We investigated genetic structure and radiation patterns against temporal and spatial dimensions since the
Miocene in the Psammobates tentorius species complex, using multiple types of DNA markers and niche modelling
analyses. Cladogenesis in P. tentorius started in the late Miocene (11.63–5.33 Ma) when populations dispersed from
north to south to form two geographically isolated groups. The northern group diverged into a clade north of the
Orange River (OR), followed by the splitting of the group south of the OR into a western and an interior clade. The
latter divergence corresponded to the intensifcation of the cold Benguela current, which caused western aridifcation
and rainfall seasonality. In the south, tectonic uplift and subsequent exhumation, together with climatic fuctuations
seemed responsible for radiations among the four southern clades since the late Miocene. We found that each clade
occurred in a habitat shaped by diferent climatic parameters, and that the niches difered substantially among the
clades of the northern group but were similar among clades of the southern group.
Conclusion: Climatic shifts, and biome and geographic changes were possibly the three major driving forces shaping cladogenesis and genetic structure in Southern African tortoise species. Our results revealed that the cladogenesis
of the P. tentorius species complex was probably shaped by environmental cooling, biome shifts and topographic
uplift in Southern Africa since the late Miocene. The Last Glacial Maximum (LGM) may have impacted the distribution
of P. tentorius substantially. We found the taxonomic diversify of the P. tentorius species complex to be highest in the
Greater Cape Floristic Region. All seven clades discovered warrant conservation attention, particularly Ptt-B–Ptr, Ptt-A
and Pv-
The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study
AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease
Biodiversity loss and its impact on humanity
The most unique feature of Earth is the existence of life, and the most extraordinary feature of life is
its diversity. Approximately 9 million types of plants, animals, protists and fungi inhabit the earth.
So, too, do 7 billion people. Two decades ago, at the first Earth Summit, the vast majority of the
world's nations declared that human actions were dismantling Earth's ecosystems, eliminating genes,
30 species, and biological traits at an alarming rate. This observation led to a daunting question: How
will loss of biological diversity alter the functioning of ecosystems and their ability to provide society
with the goods and services needed to prosper
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