Acute thrombosis of the superior mesenteric artery in a 39-year-old woman with protein-S deficiency: a case report

<p>Abstract</p> <p>Introduction</p> <p>Acute thromboembolic occlusion of the superior mesenteric artery is a condition with an unfavorable prognosis. Treatment of this condition is focused on early diagnosis, surgical or intravascular restoration of blood flow to the ischemic intestine, surgical resection of the necrotic bowel and supportive intensive care. In this report, we describe a case of a 39-year-old woman who developed a small bowel infarct because of an acute thrombotic occlusion of the superior mesenteric artery, also involving the splenic artery.</p> <p>Case presentation</p> <p>A 39-year-old Caucasian woman presented with acute abdominal pain and signs of intestinal occlusion. The patient was given an abdominal computed tomography scan and ultrasonography in association with Doppler ultrasonography, highlighting a thrombosis of the celiac trunk, of the superior mesenteric artery, and of the splenic artery. She immediately underwent an explorative laparotomy, and revascularization was performed by thromboendarterectomy with a Fogarty catheter. In the following postoperative days, she was given a scheduled second and third look, evidencing necrotic jejunal and ileal handles. During all the surgical procedures, we performed intraoperative Doppler ultrasound of the superior mesenteric artery and celiac trunk to control the arterial flow without evidence of a new thrombosis.</p> <p>Conclusion</p> <p>Acute mesenteric ischemia is a rare abdominal emergency that is characterized by a high mortality rate. Generally, acute mesenteric ischemia is due to an impaired blood supply to the intestine caused by thromboembolic phenomena. These phenomena may be associated with a variety of congenital prothrombotic disorders. A prompt diagnosis is a prerequisite for successful treatment. The treatment of choice remains laparotomy and thromboendarterectomy, although some prefer an endovascular approach. A second-look laparotomy could be required to evaluate viable intestinal handles. Some authors support a laparoscopic second-look. The possibility of evaluating the arteriotomy, during a repeated laparotomy with a Doppler ultrasound, is crucial to show a new thrombosis. Although the prognosis of acute mesenteric ischemia due to an acute arterial mesenteric thrombosis remains poor, a prompt diagnosis, aggressive surgical treatment and supportive intensive care unit could improve the outcome for patients with this condition.</p

Unmasking saccadic uncrowding

Stimuli that are briefly presented around the time of saccades are often perceived with spatiotemporal distortions. These distortions do not always have deleterious effects on the visibility and identification of a stimulus. Recent studies reported that when a stimulus is the target of an intended saccade, it is released from both masking (De Pisapia, Kaunitz, & Melcher, 2010) and crowding (Harrison, Mattingley, & Remington, 2013). Here, we investigated pre-saccadic changes in single and crowded letter recognition performance in the absence (Experiment 1) and the presence (Experiment 2) of backward masks to determine the extent to which saccadic “uncrowding” and “unmasking” mechanisms are similar. Our results show that pre-saccadic improvements in letter recognition performance are mostly due to the presence of masks and/or stimulus transients which occur after the target is presented. More importantly, we did not find any decrease in crowding strength before impending saccades. A simplified version of a dual-channel neural model, originally proposed to explain masking phenomena, with several saccadic add-on mechanisms, could account for our results in Experiment 1. However, this model falls short in explaining how saccades drastically reduced the effect of backward masking (Experiment 2). The addition of a remapping mechanism that alters the relative spatial positions of stimuli was needed to fully account for the improvements observed when backward masks followed the letter stimuli. Taken together, our results (i) are inconsistent with saccadic uncrowding, (ii) strongly support saccadic unmasking, and (iii) suggest that pre-saccadic letter recognition is modulated by multiple perisaccadic mechanisms with different time courses

Unmasking Saccadic Uncrowding

Stimuli that are briefly presented around the time of saccades are often perceived with spatiotemporal distortions. These distortions do not always have deleterious effects on the visibility and identification of a stimulus. Recent studies reported that when a stimulus is the target of an intended saccade, it is released from both masking and crowding. Here, we investigated pre-saccadic changes in single and crowded letter recognition performance in the absence (Experiment 1) and the presence (Experiment 2) of backward masks to determine the extent to which saccadic “uncrowding” and “unmasking” mechanisms are similar. Our results show that pre-saccadic improvements in letter recognition performance are mostly due to the presence of masks and/or stimulus transients which occur after the target is presented. More importantly, we did not find any decrease in crowding strength before impending saccades. A simplified version of a dual-channel neural model, originally proposed to explain masking phenomena, with several saccadic add-on mechanisms, could account for our results in Experiment 1. However, this model falls short in explaining how saccades drastically reduced the effect of backward masking (Experiment 2). The addition of a remapping mechanism that alters the relative spatial positions of stimuli was needed to fully account for the improvements observed when backward masks followed the letter stimuli. Taken together, our results (i) are inconsistent with saccadic uncrowding, (ii) strongly support saccadic unmasking, and (iii) suggest that pre-saccadic letter recognition is modulated by multiple perisaccadic mechanisms with different time courses

Unmasking saccadic uncrowding.

Stimuli that are briefly presented around the time of saccades are often perceived with spatiotemporal distortions. These distortions do not always have deleterious effects on the visibility and identification of a stimulus. Recent studies reported that when a stimulus is the target of an intended saccade, it is released from both masking and crowding. Here, we investigated pre-saccadic changes in single and crowded letter recognition performance in the absence (Experiment 1) and the presence (Experiment 2) of backward masks to determine the extent to which saccadic "uncrowding" and "unmasking" mechanisms are similar. Our results show that pre-saccadic improvements in letter recognition performance are mostly due to the presence of masks and/or stimulus transients which occur after the target is presented. More importantly, we did not find any decrease in crowding strength before impending saccades. A simplified version of a dual-channel neural model, originally proposed to explain masking phenomena, with several saccadic add-on mechanisms, could account for our results in Experiment 1. However, this model falls short in explaining how saccades drastically reduced the effect of backward masking (Experiment 2). The addition of a remapping mechanism that alters the relative spatial positions of stimuli was needed to fully account for the improvements observed when backward masks followed the letter stimuli. Taken together, our results (i) are inconsistent with saccadic uncrowding, (ii) strongly support saccadic unmasking, and (iii) suggest that pre-saccadic letter recognition is modulated by multiple perisaccadic mechanisms with different time courses

Serum Potassium-Lowering Effects of Insulin Plus Dextrose and Adrenalin Treatment that Enhance Intracellular Potassium Transitions in Hyperkalemic Diarrheic Calves

The study examined the serum potassium-lowering effects of different treatment options for hyperkalemia in diarrheic calves (n=18). Calves were allocated into three treatment groups. All groups received isotonic sodium bicarbonate solution for a period of 90 minutes. The animals in group 1 received no further treatment, those in group 2 received a further dose of 50% dextrose and insulin, and those in group 3 received a further dose of adrenaline. High serum K levels in all groups significantly decreased after treatment (AT) than before treatment (BT). Serum potassium levels AT in groups 2 and 3 were found to be significantly lower than those in group 1. Increase in pH, bicarbonate and total carbon dioxide values were observed AT in all groups. However, bicarbonate and total carbon dioxide levels in the AT were not statistically significantly different from those in the adrenaline group compared with the groups 1. These parameters were significantly lower in the group 2. Moreover, the concentration of glucose in the groups 2 in contrast to the adrenalin group was higher than that in both the BT and group 1 AT. The insulin + dextrose combination and adrenaline applications in hyperkalemic calves had similar effects. However, the administration of adrenaline had a lower negative effect on metabolic acidosis treatment. (C) 2015 PVJ. All rights reservedYuzuncu Yil University Directorate of Scientific Research ProjectsYuzuncu Yil University [2007-VF-B05]This study is part of the project supported by Yuzuncu Yil University Directorate of Scientific Research Projects (Project No: 2007-VF-B05), and we thank them for their support

The effects of aglepristone alone and in combination with cloprostenol on hormonal values during termination of mid-term pregnancy in bitches

This study was designed to assess endocrine changes associated with termination of midterm pregnancy after use of two different protocols. For this purpose we compared the effects of aglepristone (AGL) alone and in combination with cloprostenol (CLO) on serum concentrations of progesterone (P-4), estradiol (E-2) and relaxin (RLN) measured at shortterm intervals during the abortion period in bitches. Fourteen pregnant bitches between day 25 and 32 of gestation were used in the study. In the AGL group (n = 7), aglepristone was administered solely (10 mg/kg body weight (BW), subcutaneously, once daily on two consecutive days) whereas in the AGL-CLO group (n = 7), aglepristone (dosage as in AGL group) and cloprostenol (1 mu g/kg BW, subcutaneously, same with aglepristone) were combined. All pregnancies were successfully terminated 5.2 1.6 days after initiation of treatments, which was significant in both groups (P> 0.05). At the time of the start of abortion (SA) and the end of abortion (EA), the mean P4 concentrations were 26.6 7.3 and 12.0 6.4 ng/ml in AGL group, and 2.7 0.7 and 0.9 0.1 ng/ml, in AGL-CLO group, respectively (P 0.05). However, markedly higher RLN concentrations (P< 0.05) were observed in the AGL group at 48 h (1.5 0.7 ng/ml) and at SA (1.6 0.5 ng/ml). The results of the present study indicate that changes in the hormonal concentrations affect the mechanism of abortion in different ways. Further in depth studies investigating changes in the expression of hormone receptors inside the ovary, endometrium and placenta might be helpful to our understanding of the endocrinological differences observed in this study. (C) 2014 Elsevier B.V. All rights reserved