Observations on some additional abnormalities in situs inversus viscerum.
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The abnormal findings in a case of Situs inversus totalis are described. The duodenum was placed abnormally and retained its primitive mesentery. The proximal 22 in of jejunum were retroperitoneal. The attachment of the root of the mesentery to the posterior abdominal wall had a 7-shaped appearance, and there was a partial failure of the primitive mesocolon to adhere to the posterior abdominal wall. The common hepatic artery arose from the superior meseneric artery, which also provided a branch to the proximal jejunal loop. The right vagus nerve was found anterior to the oesophagus at the oesophageal hiatus in the diaphragm, and the left vagus was posterior. A double ureter was present on the right side. The findings are discussed in relation to mid-gut development. (+info)
Celiomesenteric anomaly with concurrent aneurysm.
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We describe a rare case of a celiomesenteric anomaly with concurrent aneurysm. The patient, a 53-year-old man, had no abdominal pain or discomfort. The presence of a celiac artery aneurysm was suspected on the basis of the results of abdominal computerized tomographic scanning and echo ultrasound scanning performed because of proteinuria. Intra-arterial digital subtraction angiographic results showed the anomaly and aneurysm. Because of the risk of rupture of the aneurysm, the lesion was repaired surgically, with the placement of an interpositional prosthetic graft. We found no previous reports of celiomesenteric anomaly with concurrent aneurysm repaired with prosthetic graft. (+info)
Repair of type IV thoracoabdominal aneurysm with a combined endovascular and surgical approach.
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We report an unusual case of type IV Thoracoabdominal Aneurysm (TAA) with Superior Mesenteric Artery (SMA), celiac artery, and bilateral renal artery aneurysms in a patient who underwent an earlier repair of two infrarenal Abdominal Aortic Aneurysm (AAA) ruptures. Because of the presence of the visceral artery aneurysms and the earlier operation through the retroperitoneum, standard surgical treatment via a retroperitoneal approach with an inclusion grafting technique was considered difficult. A combined surgical approach achieving retrograde perfusion of all four visceral vessels and endovascular grafting allowing exclusion of the TAA was accomplished. Complete exclusion of the aneurysm and normal perfusion of the patient's viscera was documented by means of follow-up examinations at 3 and 6 months. The repair of a type IV TAA with a Combined Endovascular and Surgical Approach (CESA) allowed us to manage both the aortic and visceral aneurysms without thoracotomy or re-do retroperitoneal exposure and minimized visceral ischemia time. If the durability of this approach is confirmed, it may represent an attractive alternative in patients with aneurysmal involvement of the visceral segment of the aorta. (+info)
We used IL-6 knock-out (KO) mice to evaluate a possible role for IL-6 in the pathogenesis of splanchnic artery occlusion shock (SAO). SAO shock was induced by clamping both the superior mesenteric artery and the celiac trunk, followed by release of the clamp. There was a marked increase in the peroxynitrite formation in the plasma of the SAO-shocked IL-6 wild-type (WT) mice after reperfusion. Immunohistochemical examination demonstrated a marked increase in the immunoreactivity to nitrotyrosine in the necrotic ileum in shocked IL-6 WT mice. SAO-shocked WT mice developed a significant increase of tissue myeloperoxidase (MPO) and malondialdehyde (MDA) activity and marked histological injury to the distal ileum. SAO shock was also associated with a significant mortality (0% survival). Reperfused ileum tissue sections from SAO-shocked WT mice showed positive staining for P-selectin. Little specific staining was observed in sham-WT mice. Staining of ileum tissue obtained from sham-operated WT mice with anti-ICAM-1 antibody showed weak but diffuse staining, demonstrating that ICAM-1 is constitutively expressed. However, after SAO shock the staining intensity increased substantially in the ileum section from WT mice. Intensity and degree of P-selectin and ICAM-1 were markedly reduced in tissue section from SAO-shocked IL-6 KO mice. SAO-shocked IL-6 KO mice also show significant reduction of neutrophil infiltration into the reperfused intestine, as evidenced by reduced MPO activity, improved histological status of the reperfused tissues, reduced peroxynitrite formation, reduced MDA levels, and improved survival. In vivo treatment with anti-IL-6 significantly prevents the inflammatory process. Our results clearly demonstrate that IL-6 plays an important role in ischemia and reperfusion injury and allows the hypothesis that inhibition of IL-6 may represent a novel and possible strategy. Part of this effect may be due to inhibition of the expression of adhesion molecules and subsequent reduction of neutrophil-mediated cellular injury. (+info)
Two patterns of lipid deposition in the cholesterol-fed rabbit.
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A central feature of arterial lipid deposition is its nonuniform and variable distribution. In immature human and rabbit aortas, spontaneous lesions occur most frequently downstream of branch points, but they tend to occur upstream of the same branches at later ages. In cholesterol-fed rabbits, the juvenile pattern has been seen regardless of age. These distributions may be determined by transport properties of the arterial wall, because uptake of plasma macromolecules is elevated downstream of aortic branches in immature rabbits and upstream in mature ones, except during cholesterol feeding, when the juvenile pattern is seen in adult vessels. The effect of cholesterol could reflect its inhibitory influence on the nitric oxide (NO) pathway because the adult transport pattern is NO dependent. Using protocols expected to preserve NO function and the mature pattern of transport during hypercholesterolemia, we made 2 attempts to induce upstream disease in rabbits. In trial I, plasma concentrations of cholesterol were kept within the normal human range for 15 weeks by using dietary levels of 0.05% to 0.2%. Although disease patterns reverse with age in human vessels exposed to these concentrations, lesions in both immature and mature rabbits occurred downstream of intercostal branch ostia. Trial II used older rabbits, a different base diet containing more vitamin E (96 mg/kg rather than 57 mg/kg), and higher levels of cholesterol (1%, administered for 8 weeks). For some animals, extra vitamin E (2000 mg/kg) was added to the diet. The mature pattern of lipid deposition was apparent around intercostal branches in the first group and was accentuated by the additional vitamin E, a change that was associated with a significant increase in the plasma concentration of NO metabolites. Spontaneous lesions, assessed on the base diet, were too rare to have influenced these distributions. This is the first report of upstream disease in the cholesterol-fed rabbit. The results support but do not prove the view that NO and transport are important in atherogenesis. (+info)
Subtype specific regulation of human vascular alpha(1)-adrenergic receptors by vessel bed and age.
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BACKGROUND: alpha(1)-adrenergic receptors (alpha(1)ARs) regulate blood pressure, regional vascular resistance, and venous capacitance; the exact subtype (alpha(1a), alpha(1b), alpha(1 d)) mediating these effects is unknown and varies with species studied. In order to understand mechanisms underlying cardiovascular responses to acute stress and chronic catecholamine exposure (as seen with aging), we tested two hypotheses: (1) human alpha(1)AR subtype expression differs with vascular bed, and (2) age influences human vascular alpha(1)AR subtype expression. METHODS AND RESULTS: Five hundred vessels from 384 patients were examined for alpha(1)AR subtype distribution at mRNA and protein levels (RNase protection assays, ligand binding, contraction assays). Overall vessel alpha(1)AR density is 16+/-2.3fmol/mg total protein. alpha(1a)AR predominates in arteries at mRNA (P<0.001) and protein (P<0.05) levels; all 3 subtypes are present in veins. Furthermore, alpha(1)AR mRNA subtype expression varies with vessel bed (alpha(1a) higher in splanchnic versus central arteries, P<0.05); competition analysis (selected vessels) and functional assays demonstrate alpha(1a) and alpha(1b)-mediated mammary artery contraction. Overall alpha(1)AR expression doubles with age (<55 versus > or = 65 years) in mammary artery (no change in saphenous vein), accompanied by increased alpha(1b)>alpha(1a) expression (P< = 0.001). CONCLUSIONS: Human vascular alpha(1)AR subtype distribution differs from animal models, varies with vessel bed, correlates with contraction in mammary artery, and is modulated by aging. These findings provide potential novel targets for therapeutic intervention in many clinical settings. (+info)
Beneficial effects of peroxynitrite decomposition catalyst in a rat model of splanchnic artery occlusion and reperfusion.
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The aim of the present study was to investigate the protective effect of the peroxynitrite decomposition catalyst 5,10,15, 20-tetrakis(2,4,6-trimethyl-3,5-disulfonatophenyl)-porphyrinato iron (III) (FeTMPS) in a model of splanchnic artery occlusion shock (SAO). SAO shock was induced in rats by clamping both the superior mesenteric artery and the celiac trunk for 45 min, followed by release of the clamp (reperfusion). At 60 min after reperfusion, animals were killed for histological examination and biochemical studies. There was a marked increase in the oxidation of dihydrorhodamine 123 to rhodamine (a marker of peroxynitrite-induced oxidative processes) in the plasma of the SAO-shocked rats after reperfusion, but not during ischemia alone. Immunohistochemical examination demonstrated a marked increase in the immunoreactivity to nitrotyrosine, an index of nitrogen species such as peroxynitrite, in the necrotic ileum in shocked rats. SAO-shocked rats developed a significant increase of tissue myeloperoxidase and malonaldehyde activity, and marked histological injury to the distal ileum. SAO shock was also associated with a significant mortality (0% survival at 2 h after reperfusion). Reperfused ileum tissue sections from SAO-shocked rats showed positive staining for P-selectin localized mainly in the vascular endothelial cells. Ileum tissue sections obtained from SAO-shocked rats and stained with antibody to ICAM-1 showed a diffuse staining. Administration of FeTMPS significantly reduced ischemia/reperfusion injury in the bowel, and reduced lipid and the production of peroxynitrite during reperfusion. Treatment with PN catalyst also markedly reduced the intensity and degree of P-selectin and ICAM-1 staining in tissue sections from SAO-shocked rats and improved survival. Our results clearly demonstrate that peroxynitrite decomposition catalysts exert a protective effect in SAO and that this effect may be due to inhibition of the expression of adhesion molecules and the tissue damage associated with peroxynitrite-related pathways. (+info)
Emergency arteriography in acute gastrointestinal bleeding.
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Emergency arteriography was carried out on 35 patients with acute gastrointestinal bleeding, in 31 of them within two hours of active bleeding (a haematemisis; a diagnostic change in central venous pressure, pulse rate, or blood pressure; or gastric aspiration of fresh blood). A definite site of bleeding was identified in 27 patients (77%)-this being a small-intestinal vascular abnormality in three--and a probable site in three. Confirmation of the bleeding site was obtained in 20 out of 23 patients treated surgically. An intra-arterial vasoconstrictor infusion was given as a temporary measure before surgery in seven patients, only one of whom showed active bleeding at operation. An intra-arterial vasoconstrictor infusion was tried as definitive treatment in an additional 10 patients, but in four out of seven with a chronic ulcer bleeding recurred after 5-68 hours and was therefore treated surgically. We recommend the diagnostic use of arteriography in patients with reliable evidence of active bleeding if its site cannot be determined by endoscopy. We do not recommend its therapeutic use in those with a chronic ulcer, except to facilitate resuscitation before surgery; further studies are needed to define its role in those with an acute lesion. (+info)