Adaptations of the amphibian egg and hatchling for terrestrial nesting in the Wenxian newt (Tylototriton wenxianensis)

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Matrix metalloproteinase-9 in relation to patients with complications after colorectal surgery: a systematic review

Purpose: Anastomotic leakage (AL) is the most severe complication following colorectal resection and is associated with increased mortality. The main group of enzymes responsible for collagen and protein degradation in the extracellular matrix is matrix metalloproteinases. The literature is conflicting regarding anastomotic leakage and the degradation of extracellular collagen by matrix metalloproteinase-9 (MMP-9). In this systematic review, the

Reproduction, development, and growth response to captive diets in the Shangcheng stout salamander, Pachyhynobius shangchengensis (Amphibia, Urodela, Hynobiidae)

The Shangcheng stout salamander (Pachyhynobius shangchengensis) is a poorly known stream dwelling hynobiid salamander from China. We studied the reproduction, development and growth response of the salamander to different diets in captivity. Two females each produced two unique, striated egg sacs, with each containing 18 and 20, and 22 and 32 white eggs with an average diameter of 3.3 mm. Hatchlings (n = 27) had front- and hind-limb buds with interdigit membranes and a large yolk sac, and developed cornified finger and toe tips during further development. Metamorphosis occurred between d 441 and d 454 after hatching at an average total length of 94.8 mm (n = 21). These reproductive and developmental traits fit in well with the ancestral state reconstruction in hynobiids. If corrected for dry mass, feed conversion ratios obtained by feeding bloodworms (Chironomidae) to R shangchengensis larvae and mealworms (Tenebrio molitor) to postmetamorphs, were very low (0.33 and 0.34 respectively), equaling a very high mass conversion efficiency

Matrix metalloproteinase-9 in relation to patients with complications after colorectal surgery: a systematic review

Purpose: Anastomotic leakage (AL) is the most severe complication following colorectal resection and is associated with increased mortality. The main group of enzymes responsible for collagen and protein degradation in the extracellular matrix is matrix metalloproteinases. The literature is conflicting regarding anastomotic leakage and the degradation of extracellular collagen by matrix metalloproteinase-9 (MMP-9). In this systematic review, the possible correlation between anastomotic leakage after colorectal surgery and MMP-9 activity is investigated. Methods: Embase, MEDLINE, Cochrane, and Web of Science databases were searched up to 3 February 2020. All published articles that reported on the relationship between MMP-9 and anastomotic leakage were selected. Both human and animal studies were found eligible. The correlation between MMP-9 expression and anastomotic leakage after colorectal surgery. Results: Seven human studies and five animal studies were included for analysis. The human studies were subdivided into those assessing MMP-9 in peritoneal drain fluid, intestinal biopsies, and blood samples. Five out of seven human studies reported elevated levels of MMP-9 in patients with anastomotic leakage on different postoperative moments. The animal studies demonstrated that MMP-9 activity was highest in the direct vicinity of an anastomosis. Moreover, MMP-9 activity was significantly reduced in areas further proximally and distally from the anastomosis and was nearly or completely absent in uninjured tissue. Conclusion: Current literature shows some relation between MMP-9 activity and colorectal AL, but the evidence is inconsistent. Innovative techniques should further investigate the value of MMP-9 as a clinical biomarker for early detection, prevention, or treatment of AL

Distribution, ecology and conservation of Ommatotriton vittatus and Salamandra infraimmaculata in Syria

The distribution, ecology and conservation status of the Syrian urodeles Salamandra infraimmaculata and Ommatotriton vittatus are poorly known. We present the results of a field study, conducted in February 2009. Salamandra infraimmaculata was found at six localities, ranging from 228 to 960 m a.s.l., and co-occurred with O. vittatus at three localities. All localities were near small, clear streams or springs. Temperatures ranged from 9.4 to 16.4 degrees C, pH 7.5-8.5, GH 3-18 and KH 3-18. The distribution model of S. infraimmaculata reveals that the distribution of this species is nearly entirely shaped by precipitation in the coldest quarter "92.9% contribution to the model". The rarity of suitable surface waters is probably the main reason for the supposed scarcity of this species in northwestern Syria. Tapping a water source for drinking water resulted in one case in extensive mortality of larvae. Ommatotriton vittatus was found at nine different localities, ranging from 172 to 960 m a.s.l. Habitat characteristics, water quality and morphological data were recorded. The average total length of adult O. vittatus was 116 mm (range 93-138 mm, n = 22) for males and 93 mm (range 86-108 mm, n = 34) for females. Mean weight was 6.7 g for males and 3.9 for females. The mean body condition index of females was comparable to that of males. Water temperatures ranged from 8.7 to 14.6 degrees C, pH 7.5-8.5, GH 3-18 and KH 3-18. The distribution model of O. vittatus reveals that the distribution of this species is mainly shaped by precipitation, both during the winter and summer periods. The collection of large numbers of adult O. vittatus for fish bait was observed

A survey for Batrachochytrium dendrobatidis in endangered and highly susceptible Vietnamese salamanders (Tylototriton spp.)

Until now, Asian amphibians appear to have largely escaped declines driven by chytridiomycosis. Vietnamese salamanders that belong to the genus Tylototriton are rare and have a patchy distribution in mountainous areas, falling within the proposed environmental envelope of chytrid infections, surrounded by Batrachochytrium dendrobatidis infected regions. If these salamanders are susceptible to chytridiomycosis, then their populations could be highly vulnerable after the introduction of B. dendrobatidis. Examination for the presence of the chytrid fungus in skin swabs from 19 Tylototriton asperrimus and 104 Tylototriton vietnamensis by using quantitative polymerase chain reaction was performed. Susceptibility of T. asperrimus to experimental infection by using the global panzootic lineage (BdGPL) strain of B. dendrobatidis was examined. The fungus was absent in all samples from all wild salamanders examined. Inoculation with the BdGPL strain resulted in mortality of all five inoculated salamanders within 3 weeks after inoculation with infected animals that manifested severe orthokeratotic hyperkeratosis, epidermal hyperplasia, and spongiosis. Although infection by B. dendrobatidis currently appears absent in Vietnamese Tylototriton populations, the rarity of these animals, their pronounced susceptibility to chytridiomycosis, an apparently suitable environmental context and increasing likelihood of the pathogen being introduced, together suggest the need of urgent measures to avoid future scenarios of extinction as witnessed in Central America and Australia