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I Huk

Publications and source records attributed to I Huk.

At least 37 records · Page 2Linked to original sources
PubMed1997

L-arginine treatment alters the kinetics of nitric oxide and superoxide release and reduces ischemia/reperfusion injury in skeletal muscle.

BACKGROUND: Constitutive nitric oxide synthase (cNOS) may produce species involved in ischemia/reperfusion (I/R) injury: NO in the presence of sufficient L-arginine and superoxide at the diminished local L-arginine concentration accompanying I/R. METHODS AND RESULTS: During hindlimb I/R (2.5 hours/2 hours), in vivo NO was continuously monitored (porphyrinic sensor), and L-arginine (chromatography), superoxide (chemiluminescence), and I/R injury were measured intermittently. Normal rabbits were compared with those infused with L-arginine 4 mg x kg(-1) x min(-1) for 1 hour. In both groups, approximately 6 minutes into ischemia, a rapid increase of NO from its basal level of 50+/-17 to 115+/-7 nmol/L, P<.005 (microvessels), was observed. In animals not treated with L-arginine, NO dropped below basal to undetectable levels (<1 nmol/L) during reperfusion. In animals treated with L-arginine, the decrease of NO was slower, such that substantial amounts accumulated during reperfusion (25 nmol/L). Decreased NO during I/R was accompanied by increased superoxide, which during reperfusion reached 50 nmol/L without or 23 nmol/L with L-arginine treatment. Calcium-dependent cNOS was a major source of superoxide release (inhibited 70% by L-NMMA and 25% by L-NAME) during I/R. CONCLUSIONS: L-Arginine treatment decreased superoxide generation by cNOS while increasing NO accumulation, leading to protection from constriction (microvessel area, 17.77+/-0.95 versus 11.66+/-2.21 microm2 untreated, P<.0005) and reduction of edema after reperfusion (interfiber area, 16.56+/-2.13% versus 27.68+/-7.70% untreated, P<.005).

Animals↗
PubMed1997

Nitric oxide is the mediator of both endothelium-dependent relaxation and hyperpolarization of the rabbit carotid artery.

It is controversial whether the endothelial cell release of nitric oxide (NO) or a different factor(s) accounts for endothelium-dependent hyperpolarization, because in many arteries endothelium-dependent relaxation and hyperpolarization resists inhibitors of NO synthase. The contribution of NO to acetylcholine-induced endothelium-dependent hyperpolarization and relaxation of the rabbit carotid artery was determined by measuring NO with electrochemical and chemiluminescence techniques. In the presence of phenylephrine to depolarize and contract the smooth muscle cells, acetylcholine caused concentration-dependent hyperpolarization and relaxation which were closely correlated to the release of NO. N(omega)-nitro-L-arginine methyl ester (30 microM) partially reduced the release of NO and caused a similar reduction in smooth muscle cell relaxation and hyperpolarization. To determine if the residual responses were mediated by another endothelium-derived mediator or NO released despite treatment with N(omega)-nitro-L-arginine methyl ester, N(omega)-nitro-L-arginine (300 microM) was added. The combined inhibitors further reduced, but did not eliminate, NO release, smooth muscle relaxation, and hyperpolarization. Hyperpolarization and relaxation to acetylcholine remained closely correlated with the release of NO in the presence of the inhibitors. In addition, the NO donor, SIN-1, caused hyperpolarization and relaxation which correlated with the concentrations of NO that it released. These studies indicate that (i) the release of NO by acetylcholine is only partially inhibited by these inhibitors of NO synthase when used even at high concentrations, and (ii) NO rather than another factor accounts fully for endothelium-dependent responses of the rabbit carotid artery.

Animals↗
PubMed1997

Thromboembolic complications in a patient with heparin-induced thrombocytopenia (HIT) showing cross-reactivity to a low molecular weight heparin-treatment with Org 10172 (Lomoparan).

Heparin-induced thrombocytopenia is an immuno-mediated life-threatening side effect of heparin therapy which poses difficulties in diagnosis and major therapeutic problems. Heparin must be instantly discontinued. We describe the case of a 60-year-old male patient with type II heparin-induced thrombocytopenia, complicated by progressive deep venous thrombosis and pulmonary embolism. He failed to improve when therapy was continued with a low molecular weight heparin (Fragmin) and high doses of intravenous immunoglobulins were administered. The test for heparin-dependent platelet aggregation was positive for unfractionated heparin and low molecular weight heparin, but negative for the heparinoid Org 10172. During subsequent anticoagulant therapy with Org 10172 for seven days the number of platelets increased rapidly and the patient recovered. Nine months later Org 10172 was used again in this patient for thrombosis prophylaxis without any adverse effects. In patients with heparin-induced thrombocytopenia requiring immediately acting anticoagulant therapy, Org 10172 can be considered as an effective alternative drug to unfractionated and low molecular weight heparins.

Anticoagulants↗
PubMed1997

Endovascular AAA treatment: expensive prestige or economic alternative?

OBJECTIVES: To compare the costs of endovascular aneurysm treatment versus open surgery during the perioperative period. METHODS: Retrospective analysis of a consecutive series of 44 patients undergoing infrarenal abdominal aneurysm repair from February 1995 to March 1996 at a university teaching hospital. RESULTS: No endovascular procedure was converted to open repair. Operative time was shorter for endovascular treatment (207.6 min vs. 229.1 min, n.s.), as well as postoperative intensive care unit stay (ICU, 22.7 h vs. 55.0 h, p = 0.017) and the postoperative recovery period (5.6 days vs. 13.3 days, p < 0.001). Open surgery generated significantly more costs (25,374.07 ECU vs. 22,268.78 ECU, p < 0.001), despite evaluation and a more expensive endovascular procedure (10,699.48 ECU vs. 4032.01 ECU, p < 0.001). During the study, costs for open surgery exceeded the cost for endovascular treatment by 13.95%. CONCLUSIONS: Endovascular aneurysm treatment is cost effective and less expensive than open surgery. The main reason for cost saving is faster patient recovery after surgery, associated with a shorter LOS in the patients treated with endovascular procedure.

Aged↗
PubMed1997

[Abdominal aortic aneurysm: surgery, indications, technique, outcome].

The fate of a patient with an abdominal aortic aneurysm] (AAA) is influenced by the risk of rupture and embolism. When the indication for operation is considered, individual associated risk factors have to be taken into account. With regard to the literature, the following recommendations concerning indication for surgery can be given: emergency surgery for symptomatic or ruptured aneurysm; elective surgery: aneurysms 5 cm diameter or growing AAA 5 mm/year, patient with acceptable individual risk for operation; asymptomatic aneurysms less than 5 cm in diameter, without growth in patients aged over 75 years and/or considerable perioperative risk should not be operated on: sonography should be done 3-monthly as a continuing control. Finally the results in our institution are presented for elective surgery: 30-day mortality 3.5%, AAA with rupture, no shock: 20%, ruptured AAA with shock 47%, respectively.

Aortic Dissection↗
PubMed1997

[Acute mesenteric ischemia].

UNLABELLED: Acute mesenteric ischemia is a life-threatening vascular emergency. A retrospective analysis of our patients was performed to describe the development of the various procedures of diagnostic assessment and treatment between 1970 and 1996, to show the influence on survival and to define recent standards. PATIENTS: Between 1970 and 1996, 145 patients, 75 male and 70 female, suffering from acute mesenteric ischemia, have been treated at the Department of Surgery-University Hospital Vienna. RESULTS: In most cases AMI was caused by arterial embolism (64.1%, n = 93) followed by arterial thrombosis (27.6%, n= 40). Venous thrombosis (3.5%, n = 5) and non-occlusive AMI (4.8%, n = 7) were rare events. Serum lactate level has been determined routinely in all patients having been admitted with acute abdomen since 1984 and turned out to be positive in 81.2% (mean value 9.81 (3.21-22.3) mmol/l). Abdominal x-ray gave only in some individual cases special hints to the advanced intestinal gangrene. Abdominal sonography led to the correct diagnostic assessment in 52 patients (= 35.8%). Angiography was in 92% conclusive for the diagnosis. Abdominal CT led to establish the correct diagnosis in > 80%. Our series with revascularisation (thrombectomy/embolectomy or bypass) has resulted in 73.8% patient survival with intestine having been maintained in the most favourable cases. CONCLUSIONS: Early diagnostic assessment and treatment are decisive for survival. Abdominal-CT, angiography and serum-lactate constitute quick and reliable means to provide diagnosis and to judge the stage of AMI in addition to meticulous examination of patients' history, symptoms and physical conditions.

Acute Disease↗
PubMed1997

In situ measurement of nitric oxide, superoxide and peroxynitrite during endotoxemia.

We report in vivo and ex vivo measurements of nitric oxide (electrochemical), ex vivo in situ measurements of superoxide (chemiluminescence) and peroxynitrite (chemiluminescence) and delineate the effect of endotoxemia on nitric oxide, superoxide and peroxynitrite release in aorta of rats. Nitric oxide release was measured in the aorta wall. An increase of nitric oxide concentration was observed immediately after administration of lipopolysaccharide (Escherichia coli serotype 0127: B8, 20 mg/kg), reaching a plateau ((50 nmol/L) after 180 +/- 50 seconds; the plateau was followed by decreasing nitric oxide concentration and its subsequent gradual small increase after 45 minutes. Superoxide and peroxynitrite production increased dramatically during endotoxemia. Superoxide concentration increased from 10 +/- 2 nmol/L to 28 +/- 3 nmol/L at one hour, and reached a 50 nmol/L plateau at 4 hours. The pattern of peroxynitrite release paralleled the pattern of superoxide release during the time course of endotoxemia. Diametrical alteration of nitric oxide and superoxide concentration with subsequent production of peroxynitrite may be a major cause of endothelial cell injury during endotoxemia.

Animals↗
PubMed1994

[Emergency management of ruptured/dissecting aortic aneurysm--diagnosis and therapeutic strategies].

Between December 1991 and January 1994 fifteen patients with a ruptured abdominal aortic aneurysm and seven patients with a dissecting aortic aneurysm were treated in our emergency department. Dissection/rupture of an aortic aneurysm is still a dramatic event with poor outcome, whereby survival depends largely on early diagnosis. In most cases the diagnosis can be made with reasonable assurance by history taking and physical examination. The most frequent differential diagnoses are pulmonary embolism and myocardial infarction (thoracic aneurysms) and renal or biliary colic and lumbago (abdominal aneurysms). The largest delay in commencing therapy is caused by patients' hesitation to call the Emergency Medical Service. Chest X-ray, echocardiography and abdominal sonography are of high diagnostic value, computed tomography confirms the diagnosis in most cases. Our Emergency Department provides the facilities for rapid diagnosis and interdisciplinary preoperative management of dissecting/ruptured aortic aneurysms.

Adult↗
PubMed1994

[Surgical therapy of acute thrombosis of leg-pelvic veins].

A series of 213 consecutive patients suffering from acute iliofemoral vein thrombosis who underwent venous thrombectomy is analyzed. Surgery was performed from an inguinal approach with a Fogarty-balloon-catheter from the proximal vessel and by bimanual exprimation from the femoral and popliteal veins. Post-operative oral anticoagulation treatment was attempted whenever possible. Long term results obtained in 130 patients after a median follow-up of 78 months (44% free of symptoms, 33% PTS [postthrombolic syndrome] I, 15% PTS II, 8% PTS III) showed a significant correlation to the duration of preoperative anamnesis: < or = 5 days: 64% free of symptoms, > 5 days: 34% free of symptoms, the rate of PTS III was equally distributed in the group with long (< or = 5 days) and short (> 5 days) anamnesis (8 and 9% respectively). Postoperative Dicumarol-therapy decreased the rate of severe PTS: 28% without, respectively 10% with therapy. If the medication was cancelled aggravation of the clinical symptoms in 1 third of the patients was observed. Venous thrombectomy is an important treatment option in patients with contraindications to thrombolytic therapy. With patients younger than 65 years and short anamnesis functional results are acceptable, high risk patients (severe cardiac disease and previous pulmonary embolism) should be treated with medical therapy only.

Female↗
PubMed1993

[Macroembolism as a complication of ultra-high dose urokinase lysis of occlusion of a bifurcation prosthesis].

The case of a 70-year-old woman suffering from a long occlusion of the right branch of an aortobifemoral dacron-graft implanted six years ago is reported. Patency could be achieved by a systemic application of an ultrahigh dose of urokinase (UHUK = 9,000,000 I.U/6 h, intermittent daily application, two cycles). As a major complication macro-embolism to the popliteal artery and to the superficial femoral artery occurred, however. A further cycle of UHUK, local thrombolytic therapy (12 mg rtPA) and surgical thrombectomy failed to achieve persistent recanalization. So the patient finally had to be provided with a femoro-crural composite bypass. In conclusion, in a systemic thrombolytic therapy of occlusions of dacron grafts in the aorto-iliacal area a standard dose of urokinase (initial dose 600,000 I.U., maintenance dose 150,000 I.U./h, infusion pump) is recommended.

Aged↗
PubMed1991

[The status of carotid artery surgery today: technique, indications, results].

Carotid artery endarterectomy (CAE) is a surgical standard procedure today. The indication is the symptomatic patient (Stage II) with transient ischemic attacks (TIA) and stenosis of the internal carotid artery (ACI). Data of several studies have yielded a highly restrictive policy toward operative procedures in asymptomatic patients (Stage I) with carotid bruit or ACI-stenosis. Furthermore there emerged wide consensus, that patients with frank stroke (Stage III) should not be operated upon. As diagnostic procedures highly advanced non invasive procedures came up during the last decade, as well as computerized tomography and digital subtraction angiography. The operative procedure is performed in general anesthesia with controlled hypertension during the clamping period (n = 650). Perioperative results without using a shunt are not different to those with a shunt. During the last 5 year period our results yielded a 1% perioperative central permanent neurological deficit rate (CPNDR) and a 1% operative mortality. During a 51 months median observation period 1.5% presented again with transient ischemic attacks-with TIA; 0.6% developed a stroke and 2.2% deceased by cerebral complications yielding at totally 4.3% long term complication rate. The annual rates are 0.3%, 0.1% respectively 0.5%, totally 0.9%. In conclusion CAE can be offered as a safe surgical stroke preventing procedure in symptomatic TIA patients with ACI stenoses in our institution. Perioperative as well as long term results are yielding a high standard and are clearly better than those without operation.

Carotid Artery Diseases↗
PubMed1990

Patency rate of implantable devices during long-term intraarterial chemotherapy.

Intraarterial implantable drug delivery systems have been considered as an alternative method for treating patients with unresectable liver malignancies. However, catheter problems with external implanted devices have resulted in limited application of chemotherapy. The introduction of subcutaneous devices offers an opportunity for long-term locoregional chemotherapy. Twelve external intraarterial catheters were implanted into 12 patients and 52 subcutaneously placed devices into 51 patients, all with various hepatic malignancies. Retrospective analyses comparing those two intraarterial systems were conducted taking into account the function and complication rate (hepatic artery thrombosis, infection, leaking, hemorrhage, and dislocation). The follow-up time for the external system was two to eight months (median five weeks), the thrombosis rate 33.3%, and the infection rate 25%. One instance of severe bleeding from the hepatic artery occurred during chemotherapy. One catheter dislocated. For the subcutaneously implanted intraarterial devices the follow-up time was five to forty-one months (median sixteen months), the thrombotic complication rate 17.3%, and the infection rate 7.6% (all patients with simultaneous bowel surgery). Catheter dislocation one year later required reimplantation; in 1 patient therapy had to be discontinued because of a catheter leak. The overall function rate was 71.3% with a median follow-up time of eight months. Anticoagulation therapy for subcutaneously implanted devices starting from the beginning of intraarterial chemotherapy is recommended to achieve long-term patency. No implantation should be preformed simultaneously with bowel surgery. The subcutaneously placed intraarterial devices had a higher function rate and were available for a longer period as compared with external implanted catheters.

Equipment Failure↗
PubMed1990

The therapy of iatrogenic lesions of the bile duct.

Forty-three patients were operated on for iatrogenic lesions of the bile duct. Only one patient had a biliary lesion which occurred in the course of distal gastric resection. All other lesions were observed during cholecystectomy. Injury of the bile duct was detected intraoperatively in sixteen cases. In 10 patients, lesions were observed in the postoperative period and in 17 patients, the post-operative diagnosis was made on the basis of symptoms of stenosis of the bile duct. Satisfactory results can be obtained by suturing the common bile duct and splinting with a T-tube where the lesion is partial and detected in the course of surgery. In the case of patients with strictures, an anastomosis (choledochojejunostomy Roux-en-Y loop) should be performed. Strictures involving hepatic bifurcation and the right hepatic duct have a higher incidence of restenosis, and transhepatic splinting of the anastomosis can therefore produce better results. Long-term transhepatic drainage has the advantage that replacement of the drain is relatively straightforward and complete dislocation impossible. Four of our patients died postoperatively, three of multiple septic organ failure due to preoperative biliary peritonitis or cholangitis, and one of a pulmonary embolism. Satisfactory long-term results after correction of an iatrogenic lesion of the bile duct can be obtained if the corrective procedure is undertaken immediately, prior to the onset of biliary cirrhosis.

Adult↗
PubMed1989

Groin infections following vascular surgery: obturator bypass (BYP) versus "biologic coverage" (TRP)--a comparative analysis.

Deep infections in the groin complicating vascular surgical procedures pose a serious problem, in the treatment of which two alternative methods are available: (1) Removal of the graft and the construction of an extra anatomic bypass (obturator canal bypass, BYP), or (2) retaining the graft and achieving healing of the infected wound by various biological materials, such as omentum or an inferior rectus abdominis muscle flap (TRP). The probability of patient and limb survival was estimated by the Kaplan-Meier method and possible differences between both groups checked using Breslow's and Mantel's tests. No statistically significant differences were found and a variety of factors with potential influence on the outcome were considered equally balanced. However, as soon as the catastrophic event of infection plus haemorrhage enforced emergency surgery, the incidence of success differed markedly: in the BYP group 6 infections healed out of 8 and in the TRP group 1 out of 6.

Adult↗