Acute liver failure following hemodialysis arteriovenous graft placement: a case report

<p>Abstract</p> <p>Introduction</p> <p>Severe high-output cardiac failure is a serious complication of high-flow vascular access requiring immediate intervention. Ischemic hepatitis is defined as a massive increase in serum transaminase levels due to an imbalance between hepatic oxygen supply and demand in the absence of other acute causes of liver damage. It is typically preceded by hypotension, hypoxemia, or both, and occurs mostly in elderly patients with right-sided congestive heart failure.</p> <p>Case presentation</p> <p>We report a fatal case of acute liver failure in an 84-year-old Caucasian man with high-output cardiac failure due to arteriovenous hemodialysis access. The chronological sequence of acute liver failure in the context of vascular access created two days before suggests that ischemic hepatitis was the result of high-output cardiac failure due to vascular access.</p> <p>Conclusions</p> <p>A thorough cardiac assessment should be performed in patients with severe cardiac disease prior to placing an arteriovenous access, and arteriovenous fistula should be the preferred vascular access.</p

Do herbivorous minnows have “plug-flow reactor” guts? Evidence from digestive enzyme activities, gastrointestinal fermentation, and luminal nutrient concentrations

Few investigations have empirically analyzed fish gut function in the context of chemical reactor models. In this study, digestive enzyme activities, levels of gastrointestinal fermentation products [short chain fatty acids (SCFA)], luminal nutrient concentrations, and the mass of gut contents were measured along the digestive tract in herbivorous and carnivorous minnows to ascertain whether their guts function as “plug-flow reactors” (PFRs). Four of the species, Campostoma anomalum, C. ornatum, C. oligolepis, and C. pauciradii, are members of a monophyletic herbivorous clade, whereas the fifth species, Nocomis micropogon, is a carnivore from an adjacent carnivorous clade. In the context of a PFR model, the activities of amylase, trypsin and lipase, and the concentrations of glucose, protein, and lipid were predicted to decrease moving from the proximal to the distal intestine. I found support for this as these enzyme activities and nutrient concentrations generally decreased moving distally along the intestine of the four Campostoma species. Furthermore, gut content mass and the low SCFA concentrations did not change (increase or decrease) along the gut of any species. Combined with a previous investigation suggesting that species of Campostoma have rapid gut throughput rates, the data presented here generally support Campostoma as having guts that function as PFRs. The carnivorous N. micropogon showed some differences in the measured parameters, which were interpreted in the contexts of intake and retention time to suggest that PFR function breaks down in this carnivorous species

Design-based research and the learning designer

The role of the learning designer has expanded from the commonly known activities of an instructional designer to incorporate a range of new roles, largely prompted by new technologies. In this paper, the authors articulate an approach that further extends the role of the learning designer to encompass evaluation and design-based research, in collaboration with the subject matter expert. Such collaboration is professionally enhancing for both parties, and adds to the sum of knowledge on the effective design of learning environments, by documenting and disseminating the learning design process

Lower Cambrian melanosclerites and foraminiferal linings from the Lontova Formation, St. Petersburg, Russia

This paper documents the first evidence for melanosclerites and foraminiferal test-linings from the Cambrian. While agglutinated foraminifera are known from the Precambrian–Cambrian transition, their tests are delicate and not commonly recovered from acid-digested samples. The material presented herein represents the organic test-linings, which preserve sufficient detail of the internal morphology of the foraminiferal test wall and gross morphology to allow identification to generic level. The occurrence of melanosclerites documented herein, extends their lower range from the Middle Ordovician to the Lower Cambrian and includes Semenola semen Schallreuter 1981, Melanosteus sp. Eisenack 1942 and Melanoclava sp. Eisenack 1942. Foraminiferal taxa include Psammosphaera Schulze 1875, Thurammina? Brady 1879, and a small tubular form (Bathysiphon?), which supplements the previously described records of Platysolenites spp., Spirosolenites spiralis Glaessner 1979 and Psammosphaera sp., which are known from their agglutinated tests rather than the test-lining. This also extends the first occurrence datum of Psammosphaera and Thurammina? to the Platysolenites partial range zone of the Lower Cambrian.9 page(s

Human-mediated prehistoric marine extinction in the tropical Pacific? Understanding the presence of Hippopus hippopus (Linn. 1758) in ancient shell middens on the Rove Peninsula, Southwest Viti Levu Island, Fiji

At the Lapita-era (1100-550 B.C.) settlements (Bourewa and Qoqo) along the Rove Peninsula in Fiji, valves of the reef-surface-dwelling giant clam Hippopus hippopus (long extirpated in Fiji) occur in shell midden. Valve size/weight increase with depth, suggesting that human predation contributed to its local disappearance. The timing of this event is constrained by (a) the confinement of H. hippopus remains to the lower part of the midden, (b) their likely association with only the stilt-platform occupation phase at both Bourewa and Qoqo (approximately 1100-900 B.C.), and (c) radiocarbon ages. All these suggest that H. hippopus disappeared from reefs here about 750 B.C. Yet human predation is not considered to be a significant cause of extirpation of H. hippopus in the entire Fiji group. More plausible is that (climate-driven) sea-level fall (55 cm) during Lapita times in Fiji (approximately 1100-550 B.C.) forced changes to coral-reef ecology that saw this sensitive species extirpated throughout the Fiji archipelago. It is also considered possible that the Lapita colonizers introduced bivalve predators or diseases to Fiji that spread independently of humans throughout these islands

Complete larval development of the Monkey River Prawn Macrobrachium lar (Palaemonidae) using a novel greenwater technique

This study documents the complete larval development of the Monkey River Prawn Macrobrachium lar using a new greenwater rearing technique. Approximately 6,000 larvae were reared for 110 days at an initial stocking density of 1 ind./6 L. Salinity at hatch was 10 ± 2 ppt and progressively increased to 30 ± 2 ppt until decapodids had metamorphosed. Temperature was maintained at 28 ± 0.5°C, pH at 7.8 ± 0.2, DO2 > 6.5 mg/L and NH4+ and NH3 ≤ 1.5 and ≤0.1 ppm respectively throughout the culture period. Larval development was extended and occurred through 13 zoeal stages, with the first decapodid measuring 6.2 ± 0.63 mm in total length observed after 77 days. 5 decapodids in total were produced, and overall survival to this stage was 0.08%. Overall, the pattern of larval growth shares similarities with those of other Macrobrachium spp. that have a prolonged/normal type of development, and it is likely that larvae underwent mark time moulting which contributed to the lengthened development duration. While this study represents a significant breakthrough in efforts to domesticate M. lar, improvement of larval survival rates and decreased time till metamorphosis are required before it can become fully viable for commercial scale aquaculture