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Biomedical subjects

F Hammer

Publications and source records attributed to F Hammer.

At least 19 recordsLinked to original sources
PubMed2001

Sufentanil potentiates the inhibitory effect of epinephrine on intestinal motility.

OBJECTIVE: The aim of our study was to evaluate the effect of the combination of different catecholamines and sufentanil on peristalsis of the isolated guinea pig small bowel in vitro. DESIGN: In vitro study on excised guinea pig small-bowel segments (8-10 segments per substance tested). SETTING: Laboratory for experimental studies at the University. SUBJECTS: Isolated guinea pig small-bowel segments. INTERVENTIONS: Excised segments of guinea pig small bowel were mounted in a tissue bath (37 degrees C) in Tyrode's solution and bubbled with carbogen (95% O2/5% CO2). The lumina were perfused with Tyrode's solution at 0.5 ml/min. The test drugs (epinephrine, norepinephrine, dobutamine, sufentanil, and a combination of these catecholamines with sufentanil) were added to the tissue bath and peristalsis recorded via changes in the intraluminal pressure. One-way and two-way ANOVA were used for statistical analysis. MEASUREMENTS AND RESULTS: All the tested substances, both individually and in combination, inhibited intestinal peristalsis in a dose-dependent manner. High doses resulted in a complete blockade of peristalsis. Preexposure of the segments to sufentanil at 0.1 nM barely influenced the effects of the catecholamines on peristalsis. However, sufentanil at 0.3 nM enhanced the antiperistaltic activity of epinephrine in a supraadditive manner, whereas the effect on norepinephrine and dobutamine was less pronounced. CONCLUSIONS: Our experimental data suggest that the combination of epinephrine and sufentanil might be the worst choice for the intensive care setting. This is due to its pronounced inhibitory effect on peristalsis in vitro at moderate and higher concentrations.

Adrenergic Agents↗
PubMed2000

Influence of treatment modality on angiographic outcome after coronary stenting in diabetic patients: a controlled study.

OBJECTIVES: This retrospective study was designed to determine the six-month angiographic outcome after stenting of native coronary arteries in insulin-treated (ITDM) and non-ITDM patients with diabetes mellitus (DM) and compare the results with those in non-DM patients. BACKGROUND: The influence of the treatment modality for DM on restenosis in patients undergoing coronary artery stenting has not been elucidated sufficiently. METHODS: A total of 1,439 (70%) of 2,061 patients underwent repeated angiography within six months of coronary stenting. The ITDM and non-ITDM (oral hypoglycemic drugs or diet) were documented in 48 (3.3%) and 177 patients (12.3%), respectively, leaving 1,214 non-DM patients. RESULTS: Baseline reference vessel diameter tended to be smaller in ITDM patients (mean, 2.73 mm) than in non-DM and non-ITDM patients (2.88 mm and 2.85 mm, respectively). However, percent diameter stenosis was not different. The median number of stents deployed was 1; median stent length was 15 mm. Statistically significant differences were present after stenting for the means of minimal lumen diameter (MLD) and acute gain between ITDM patients (MLD: 2.67 mm, acute gain: 1.98 mm) and non-DM patients (MLD: 2.81 mm, acute gain: 2.16 mm). At follow-up, percent diameter stenosis, late lumen loss and loss index were significantly higher in both non-ITDM lesions (42%, 1.14 mm and 0.56, respectively) and ITDM lesions (48%, 1.26 mm and 0.65, respectively) than in non-DM lesions (35%, 0.96 mm and 0.45, respectively). The corresponding differences between non-ITDM and ITDM lesions did not reach statistical significance. Restenosis rates in non-DM, non-ITDM and ITDM lesions were 23.8%, 32.8% (p = 0.013 vs. non-DM) and 39.6% (p = 0.02 vs. non-DM, p = 0.477 vs. non-ITDM), respectively. CONCLUSIONS: This study showed that compared with stenting in non-DM patients, stenting of native coronary arteries in DM patients is associated with significantly increased lumen renarrowing, regardless of the treatment modality for DM.

Aged↗
PubMed2000

Subintimal angioplasty of tibial vessel occlusions in the treatment of critical limb ischaemia: mid-term results.

OBJECTIVES: to evaluate the feasibility and preliminary results at 1 year of subintimal angioplasty of tibial occlusions in critical limb ischaemia (CLI). MATERIAL: from December 1997 to December 1999, we intended to treat 36 patients and 40 limbs by subintimal angioplasty of occlusions of tibial vessels. Thirty-one had gangrene or ulceration and nine had rest pain. Twenty-seven occlusions were more than 10 cm, 10 were 5 to 10 cm and three were less than 5 cm in length. Three patients had an occluded previous ipsilateral bypass graft. All patients were followed 3 monthly for a median of 10 months by means of clinical and duplex examination. RESULTS: the technical success rate was 78% (31/40). Nine technical failures were treated by conventional surgery or angioplasty of another diseased tibial vessel. The clinical success rate was 68% (27/40). Four below-the-knee amputations were performed despite a patent recanalisation. Primary and secondary patency rates at 12 months were 56% (72% without technical failures). The 12-month limb salvage rate was 81% and survival rate was 78%. Three of five complications were treated by endovascular procedures. The length of occlusion (>10 cm) but not the location of distal re-entry, the type of vessel re-entry and the presence of diabetes are predictors of technical success and patency. CONCLUSIONS: subintimal angioplasty can be used to treat tibial occlusions in patients with CLI. Technical failure does not preclude conventional surgery and complications may often be treated by endovascular procedures. However, the durability of angioplasty is as yet uncertain.

Adult↗
PubMed2000

Crushed stents in benign left brachiocephalic vein stenoses.

Two hemodialysis patients presenting with left venous arm congestion due to benign catheter-induced stenosis of the left brachiocephalic vein were treated by angioplasty and stent placement. External compression of the stents was responsible for rapid recurrence of the symptoms. No osseous or vascular malformation could be identified. Mechanical constraints induced by respiratory chest wall motion and aortic arch flow-related pulsation are proposed to explain this observation. This potential hazard should be considered when stent placement into the left brachiocephalic vein is advocated.

Adult↗
PubMed2000

Vasospasm after subarachnoid hemorrhage: diagnosis with MR angiography.

BACKGROUND AND PURPOSE: The possibility of treating intracranial vasospasm has increased the significance of its diagnosis and follow-up; however, so far, no ideal method is available. The goal of this study was to assess the accuracy of MR angiography versus intraarterial angiography (IA-DSA) in detecting vasospasm. METHODS: The study included 42 patients with acute spontaneous subarachnoid hemorrhage (SAH). Serial MR angiograms (minimum, two per patient within 10 days after the event; total, 149) were obtained prospectively using a 3D time-of-flight technique covering the circle of Willis at 0.5 T. Forty-seven MR angiograms could be compared with intraarterial angiograms obtained within 24 hours of MR angiography. Vascular narrowing on both studies was rated consensually by two pairs of neuroradiologists using a scale from 0 (no narrowing) to 3 (severe narrowing). Categories 0 and 1 were considered an absence of vasospasm and categories 2 and 3 a presence of vasospasm. RESULTS: Agreement between MR angiography and IA-DSA (assessed with weighted kappa statistics) was substantial for the middle and anterior cerebral arteries (MCA and ACA) but moderate for the internal carotid artery (ICA). The sensitivity, specificity, accuracy, and positive and negative predictive values of MR angiography for detecting patients with vasospasm were 92%, 98%, 96%, 92%, and 98%, respectively. Considering each vessel separately, specificity was high for all locations (95-99%) and sensitivity was excellent for the ACA (100%) but poorer for the ICA (25%) and MCA (56%). CONCLUSION: MR angiography at 0.5 T is capable of identifying vasospasm after acute SAH but is less sensitive than IA-DSA for depicting vasospasm in the ICA and MCA.

Acute Disease↗
PubMed1999

Ku autoimmune antigen is involved in placental regulation of rat P450c17 gene transcription.

The steroidogenic enzyme P450c17 (17alpha hydroxylase/C17,20 lyase) regulates a key branchpoint in steroidogenesis, as its activity directs the steroid biosynthetic pathways toward glucocorticoid or sex hormone synthesis. Expression of the P450c17 gene is transcriptionally regulated in steroidogenic tissues by cAMP. We showed that DNA between -84 and -55 in the rat P450c17 gene was bound uniquely by steroidogenic factor-1 (SF-1), which regulated both basal and cAMP-stimulated transcription in mouse adrenocortical and Leydig cells. SF-1 gene ablation experiments in mice indicate that SF-1 is not mandatory for placental steroidogenesis. We studied P450c17 gene regulation in the placenta using human placental JEG-3 trophoblast cells. Transfection of reporter luciferase gene constructs containing serial deletions of the 5' flanking region of the rat P450c17 gene showed that DNA between -98 and +13 mediated basal and cAMP-regulated transcription in placental JEG-3 cells, as it did in adrenal and Leydig cells. DNase footprints further identified a region between -88 and the TATA box that was bound by protein. Transfection of luciferase reporter constructs containing -84 to -55 of the rat P450c17 DNA ligated to the minimal promoter of the thymidine kinase gene showed that this DNA increased both basal and cAMP-simulated luciferase activity. Gel mobility shift assays identified two DNA-protein complexes with JEG-3 cell nuclear extracts that were different from complexes formed with MA-10 cell extracts and did not involve SF-1. Mutational analysis of the -84/-55 DNA showed that JEG-3 nuclear proteins bound to a site containing, but not identical to, the SF-1 sequence. One complex involved Ku autoimmune antigen, which bound to DNA sequence specifically. Overexpression of Ku antigen in MA-10 cells stimulated rat P450c17 gene transcription, thus demonstrating a biologic effect of Ku. Ku also bound to a similar region of the human P450c17 gene, and the DNA region to which Ku bound was transcriptionally active in JEG-3 cells. Ku was also found in extracts from rat placenta and bound to the -84/-55 rat P450c17 DNA. These data demonstrate a role of Ku in regulating P450c17 gene expression. These data further indicate that although human P450c17 is not normally expressed in the placenta, factors that could activate this gene are indeed present.

Adrenal Glands↗
PubMed1998

Diagnosis of intracranial aneurysms: accuracy of MR angiography at 0.5 T.

PURPOSE: Our goal was to determine the accuracy of MR angiography at 0.5 T for the diagnosis of intracranial aneurysms. METHODS: We retrospectively studied 140 patients, 70 with acute subarachnoid hemorrhage, who were either at high or low risk for intracranial aneurysm. Three-dimensional time-of-flight MR angiography was typically performed to cover the circle of Willis, with a volume thickness of 30 mm. Conventional spin-echo MR images and MR angiograms were reviewed together, and the results were compared with those obtained at intraarterial cerebral angiography to determine the sensitivity and specificity of MR angiography. RESULTS: Eighty-nine aneurysms (size range, 2 to 27 mm; 25 aneurysms < 5 mm) were identified at intraarterial cerebral angiography. Six aneurysms were missed by MR angiography and two were doubtful (sensitivity, 91% to 93%; specificity, 100%). Missed aneurysms were located outside the MR angiographic acquisition volume (n = 3) or on the carotid siphon (n = 3; size = 2, 3, and 5 mm). CONCLUSION: Even if MR angiography presents some restrictions in acquisition volume and spatial resolution, the detection rate of intracranial aneurysms is excellent at 0.5 T in both asymptomatic patients and in those with subarachnoid hemorrhage. A midfield system is not a restriction to the detection of intracranial aneurysms by MR examination.

Adolescent↗
PubMed1997

Saccular aneurysm of the external jugular vein, an unusual cause of neck swelling.

Enlargement of neck swelling on Valsalva maneuver raises the diagnosis of laryngocele or jugular aneurysm. When considering this latter type of lesion, though fusiform cervical venous aneurysms represent a frequent occurrence, sacciform aneurysms are much rarer. We report two exceptional cases of saccular aneurysms of the external jugular vein which presenting symptom was a neck lump that enlarged on Valsalva maneuver. Although computed tomography and selective venography allow accurate diagnosis, ultrasonography with color flow duplex imaging is the gold standard for the diagnosis of such venous aneurysms of the neck.

Adult↗
PubMed1995

[Laparoscopic treatment of recurrence and embolization failure of varicocele].

Varicocele is a benign pathology, for which the less invasive treatment is percutaneous embolisation. Literature reports results from 70 to 85% (1,2). Laparoscopic treatment seems to be a good alternative for patients suffering from a recurrence, or patients who can not be embolised. We report our experience concerning the first 13 patients treated with laparoscopic technic. In all 13 cases it was possible to practice the technic, and patients were cured.

Adolescent↗
PubMed1994

[Varicocele: treatment via percutaneous approach].

The varicocele is benign pathology which sometimes involves disorders of testicular growth. Those can cause a hypofertility. We saw in a retrospective way the 243 patients having been treated by percutaneous embolisation from May 1985 to August 1993. At 150 patients being 1 year at least of postoperative retreat, 70% of cases present a cure, 15% of patients repeated and were taken again surgically. At 8% of patients, the embolisation was not technically possible for reasons of vascular anomalies or spasm of the vein during the procedure. The morbidity of this technique is low, this involves therefore a right choice of the treatment of the varicocele which does not prevent any surgical treatment in the event of repetition or in the event of technical failure.

Adolescent↗
PubMed1992

Endometrial carcinoma in patients aged 75 years or older: outcome and complications after postoperative radiotherapy or radiotherapy alone.

A retrospective analysis is reported of 89 patients at least 75 years old (median age 79 years) treated with irradiation for endometrial carcinoma between 1972 and 1989, the median follow-up being 39 months. In 66 patients radiotherapy was given postoperatively and in one case preoperatively, 22 patients were treated with radiotherapy alone: intravaginal insertions exclusively in 22 patients (median dose 60 Gy to the mucosa) and combined with external radiotherapy in 53 patients (median external target dose 45 Gy; three or four fields, all treated daily, 1.8 to 2.0 Gy per fraction, five fractions per week; 30 Gy to the vaginal mucosa with low-dose rate). A few patients were treated with external radiotherapy or intrauterine insertions only. 65% of the patients treated with radiotherapy alone and 34% of the patients receiving postoperative radiotherapy had FIGO stage II or III disease. Five-year actuarial overall survival and disease-free survival for all patients with adenocarcinomas treated with curative intent was 47.5% and 57.2%, respectively. In 48 patients with surgical stages I and II, treated with postoperative adjuvant radiotherapy, overall actuarial survival is 58.2% and disease-free survived 65.5% at five years. After postoperative vaginal insertions only, no vaginal recurrence occurred. With combined external and intravaginal radiotherapy in surgical stage I and II, 4/36 patients (11%) showed a recurrence in the vagina only, the abdominal and pelvic recurrence rate being 8.3%. Grade 3 to 4 late toxicity was observed in 6/53 patients (11.3%) treated with external and intravaginal radiotherapy. However, in patients receiving external radiotherapy less than 45 Gy and intravaginal radiotherapy 30 to 40 Gy, as is standard postoperative adjuvant treatment today, only one grade 3 late toxicity was observed in 17 patients (5.9%). We conclude, that treatment of elderly patients with adenocarcinoma of the uterus should follow the same pattern as in younger patients, the acute side-effects and late toxicity of radiotherapy being similar.

Actuarial Analysis↗
PubMed1991

[Chorea gravidarum].

Chorea gravidarum is a rare maternal complication during pregnancy. Like the better known chorea minor it shows extrapyramidal symptoms with involuntary movements, lack of coordination, slurred speech and psychic disorders. The neurological state is normal except for a loss of muscle tone. The symptoms most commonly begin in the first trimester of pregnancy and usually resolve spontaneously after 2-3 months. The maternal mortality lies below 1%. In the case of subjectively disturbing symptoms anticonvulsive and sedative therapy with benzodiazepine or neuroleptics may be indicated. Etiological factors including rheumatic fever, chorea minor, hormonal, psychic and autoimmune disorders are discussed. Elective termination of the pregnancy is not indicated. The presented case report shows a chorea-like situation beginning in the ninth week of pregnancy.

Adult↗
PubMed1990

[Iniencephaly: prenatal and postnatal findings].

A 33-year-old para-3 was admitted in the 33rd week of gestation because of a suspected foetal anomaly. Ultrasound examination showed polyhydramnios, exaggerated cervico-thoracic lordosis and significant shortening of the spine because of a reduced number of vertebrae. The facial profile was flat, the foetal movements were rare and slow, and the extremities normal. A biopsy of the placenta revealed a normal female karyotype. Based on ultrasound examination, the diagnosis of iniencephaly was made. Because of the fatal prognosis of this malformation, labour was induced at 35 weeks of gestation. The patient delivered spontaneously. The infant died after 90 minutes. The postmortem examination confirmed the diagnosis of iniencephaly. Iniencephaly is a very rare malformation comprising a bone defect at the occiput, malformation of the cervical and thoracic vertebrae, spina bifida, and retroflexion of the head. The aetiology is not clear. 90% of the probands are female. The malformation is incompatible with survival after birth.

Abnormalities, Multiple↗
PubMed1989

[Results of treatment of 177 stage Ib and IIa cervix cancers at the Zurich University Gynecologic Clinic].

Between 1971 and 1980, 177 patients were treated for a carcinoma of the uterine cervix (145 stage Ib, 32 stage IIa) in the Department of Gynecology and Obstetrics at the University Hospital Zürich, Switzerland. There were 115 patients who underwent radical hysterectomy combined with pelvic lymphadenectomy. Of these, 91 also received radiotherapy. Surgery could not be performed on 62 patients due to internal medical problems and risks presented by anaesthesia. They were treated solely by combined radiotherapy. Of the 177 patients, 79.5% had a squamous-cell carcinoma, 14.8% an adenocarcinoma and the other 5.7% rare types of carcinomas. Of the 115 patients who were operated, metastases of pelvic lymph nodes were found in 13% and an infiltrative carcinoma of the parametrium in 8.7%. The most severe complications we had were uretero- or vesicovaginal fistulas (5.2% of all operated patients). No significant statistical difference was found in the results of the three methods of treatment. The 5-year survival rate in stage Ib was between 61 and 81% (non corrected) and between 75 and 85% (corrected). In stage IIa, there were not enough patients for valid statistical conclusions to be drawn.

Adenocarcinoma↗
PubMed1988

Changes in coronary blood flow and myocardial metabolism during aortic balloon valvuloplasty.

The effects of balloon inflation on myocardial perfusion and metabolism were studied during aortic valvuloplasty in 17 patients with aortic stenosis, including 6 with associated coronary artery disease. Coronary sinus flow and blood samples were obtained before and during the first inflation, and 5 to 10 minutes after the last inflation. During inflation, coronary blood flow decreased (272 +/- 111 standard deviation to 166 +/- 92 ml/min; p less than 0.05), myocardial oxygen uptake fell and transcardiac lactate handling shifted from extraction to production (35 +/- 54 to -41 +/- 48 mumol/min; p less than 0.01). At the end of the procedure, aortic valve area had increased from 0.51 +/- 0.22 to 0.81 +/- 0.48 cm2 (p less than 0.002). Coronary sinus flow increased slightly above control values (+6%; difference not significant) and myocardial oxygen and lactate uptakes were back to control values. However, myocardial alanine production had increased from -3.6 to -6.6 mumol/min (p less than 0.05) and glutamine production was reduced or replaced by extraction (-3.3 +/- 2.1 to 3.5 +/- 3.8 mumol/min; p less than 0.05). Recovery of coronary flow, oxygen and lactate uptakes was not significantly different in patients with or without coronary artery disease, although the former patients tended to have less glutamine extraction and less improvement in their ejection fraction at the end of the procedure. Thus, aortic balloon valvuloplasty produces brief episodes of low-flow ischemia. Recovery of oxidative metabolism is almost immediate after deflation and no detrimental effect seems to persist at the end of the procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗