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B Flor

Publications and source records attributed to B Flor.

12 recordsLinked to original sources
PubMed2001

[Bradycardia despite hyperthyroidism].

Hyperthyroidism is usually associated with tachycardia, hypothyroidism with bradycardia. After observing clinically inapparent hyperthyroidism in patients requiring pacemaker implantation, we studied the occurrence of hyperthyroidism in patients receiving a first permanent pacemaker. Of 237 patients (age 71.4 +/- 8.9 years; 54.9% females), 16 (6.75%) had subclinical (TSH < 0.1 mE/l and fT3 < or = 9.0 pmol/l) and 4 (1.69%) overt hyperthyroidism (TSH < 0.1 mE/l and fT3 > 9.0 pmol/l). Prevalence of hyperthyroidism was similar to that in the general population. Compared to euthyroid patients, in the patients with subclinical or overt hyperthyroidism there were significantly more females (n = 16) than males (n = 4; p = 0.018). Hyperthyroid patients were older (75.0 +/- 9.6 vs. 70.7 +/- 8.9 years; p = 0.015). At follow-up, all patients had a relevant proportion of pacemacer-induced beats. Clinical signs of hyperthyroidism or cardiac symptoms were not different between groups. In conclusion, bradycardia does not exclude the presence of hyperthyroidism. Temporary pacing is recommended in thyreotoxicosis with bradycardia. In contrast, primary implantation of a permanent pacemaker appears to be adequate in patients with bradycardia, cardiovascular disease and an additional diagnosis of hyperthyroidism.

Age Factors↗
PubMed2000

Bile duct injury during laparoscopic cholecystectomy: myth or reality of the learning curve?

BACKGROUND: Bile duct injury (BDI) is a severe complication of laparoscopic cholecystectomy (LC) that is probably related to the effects of the learning curve. The aim of this prospective, institutional, and longitudinal study is to compare the incidence of BDI during LC in relation to the progressive experience of surgeons. METHODS: A total of 784 LC were examined during a 6-year period. They were divided into the following three consecutive groups: group A (1993-94), group B (1995-96), and group C (1997-98). Incidence and type of BDI, experience of the surgeon, intra- or postoperative diagnosis, treatment performed to repair the injury, and early and late morbidity and mortality were evaluated. RESULTS: The overall incidence of BDI was 1.4%. There were three cases of transection of the common bile duct, four partial lesions of the bile duct, and four cystic leakages. The number of BDI was maintained over the three different time periods; there were no statistical differences in the proportion of injuries among groups. Most BDI were incurred by experienced surgeons. In all, 36% of BDI were recognized intraoperatively. Hepaticojejunostomy, direct suture over a T-tube, and closure of the cystic stump were done to repair BDI. There was no additional morbidity or mortality in the patients with BDI. CONCLUSIONS: No relation was found between the experience of the surgeon and the number of BDI over the different periods of time. Therefore, BDI during LC cannot be attributed solely to the learning curve.

Adult↗
PubMed1999

Relaxant effects of antidepressants on human isolated mesenteric arteries.

AIMS: The therapeutic action of tricyclic agents may be accompanied by unwanted effects on the cardiovascular system. The evidence for the effects on vascular and nonvascular smooth muscle comes from animal studies. Whether these studies can be extrapolated to human vessels remains to be determined. Therefore, the present study was designed to investigate the influence of amitriptyline, nortriptyline and sertraline on the contractile responses of human isolated mesenteric arteries to electrical field stimulation, noradrenaline and potassium chloride. METHODS: Arterial segments (lumen diameter 0.8-1.2 mm) were obtained from portions of the human omentum during the course of 41 abdominal operations (22 men and 19 women), and rings 3 mm long were mounted in organ baths for isometric recording of tension. In some artery rings the endothelium was removed mechanically. RESULTS: In precontracted artery rings amitriptyline, nortriptyline and sertraline (3x10(-7)-10(-4) m ) produced concentration-dependent relaxation that was independent of the presence or absence of vascular endothelium. Incubation with indomethacin (3x10(-6) m ) reduced the pD2 values thus indicating the participation of dilating prostanoid substances in this response. Amitriptyline and nortriptyline inhibited both the neurogenic-and noradrenaline-induced contractions. In contrast, only the highest concentration of sertraline reduced the adrenergic responses. Amitriptyline, nortriptyline and sertraline inhibited contractions elicited by KCl and produced rightward shifts of the concentration-response curve to CaCl2 following incubation in calcium-free solution. CONCLUSIONS: These results indicate that amitriptyline and nortriptyline could act as adrenoceptor antagonists and direct inhibitors of smooth muscle contraction of human mesenteric arteries, whereas sertraline might principally exert its action only as direct inhibitor of smooth muscle contraction. This relaxant mechanism involves an interference with the entry of calcium.

Adult↗
PubMed1997

[Primary chylopericardium--stepwise diagnosis and therapy of a differential diagnostically important illness].

Primary chylopericardium is a rare disease with a highly variable clinical course. We report on a 24-year old female with chylopericardium detected during a pulmonary infection. Despite successful treatment of the infectious disease, the chylopericardium persisted and led to cardiac tamponade. From this case, as well as from the literature, it is intriguing to postulate an inflammatory injury of preexisting anomalous lymphatic vessels leading to onset or aggravation of primary chylopericardium. The clinical hallmark of chylopericardium is a milky white, but odorless pericardial fluid at pericardiocentesis. For cases where conservative treatment and pericardiocentesis fail, we newly introduced the method of pericardio-peritoneal shunting by a pericardial window. With postoperative reaccumulation of pericardial fluid, total parenteral nutrition followed by medium chain triglyceride diet was successfully reinitiated. This combined surgical and conservative approach was performed for the first time and may have helped to avoid the more aggressive treatment of thoracic duct ligation and resection. During 2 years of follow-up the patient was asymptomatic and had no recurrence of pericardial effusion.

Adult↗
PubMed1997

Enhancement by vasopressin of adrenergic responses in human mesenteric arteries.

Vasopressin not only acts directly on blood vessels through V1-receptor stimulation but also may modulate adrenergic-mediated responses in animal experiments in vitro and in vivo. The aim of the present study was to investigate whether subpressor concentrations of vasopressin could modify the constrictor responses to norepinephrine and electrical stimulation of the perivascular nerves in human mesenteric arteries. Human mesenteric artery rings (3-3.5 mm long, 0.8-1.2 mm OD) were obtained from 38 patients undergoing abdominal operations. The arterial rings were suspended in organ bath chambers for isometric recording of tension. Vasopressin (3 x 10(-11) M) enhanced the contractions elicited by electrical stimulation at 2, 4, and 8 Hz (by 100, 100, and 72%, respectively) and produced a leftward shift of the concentration-response curves to norepinephrine (half-maximal effective concentration decreased from 2.2 x 10(-6) to 5.0 x 10(-7) M; P < 0.05) without any alteration in maximal contractions. Vasopressin also potentiated KCl- and calcium-induced contractions. The V1-receptor antagonist 1-[beta-mercapto-beta,beta-cyclopentamethylenepropionic acid-2-O-methyl-tyrosine, 8-arginine]vasopressin (10(-6) M) prevented the potentiation evoked by vasopressin in all cases. The calcium antagonist nifedipine (10(-6) M) did not affect the potentiation of electrical stimulation and norepinephrine induced by vasopressin but abolished KCl-induced contractions. The results suggest that vasopressin, in addition to its direct vasoconstrictor effect, strongly potentiates the responses to adrenergic stimulation and KCl depolarization. Both the direct and indirect effects of vasopressin appear to be mediated by V1-receptor stimulation. The amplifying effect of vasopressin on constrictor responses may be relevant in those clinical situations characterized by increased plasma vasopressin levels.

Adult↗
PubMed1995

Intermittent regional therapy with rt-PA is not superior to systemic thrombolysis in deep vein thrombosis (DVT)--a German multicenter trial.

In a prospective and randomized multicenter trial the efficacy of intermittent regional and systemic thrombolytic therapy for DVT was evaluated. 137 patients with phlebographically confirmed acute DVT above the calf region were treated with 20 mg of rt-PA for 4 h each day. Thrombolysis was applied either locally via a dorsal pedal vein of the firmly bandaged affected leg or systemically using a cubital vein. Treatment lasted for 4-7 days, and during this time unfractionated heparin was applied continuously with the dosage adjusted according to aPTT (1.5-2.0 times the normal value). A second phlebography was performed within 24 h after the end of treatment. Results were evaluated by an independent radiologist who was unaware of the treatment given. Significant thrombolytic results (e.g. lysis of more than 50% of the original thrombus and complete recanalization of all affected veins) were reached in only 1/3 of all patients. Rates of recanalization did not differ in both groups and bleeding complications occurred in 26.5%. We conclude that intermittent local or systemic application of 20 mg rt-PA seems to be ineffective in the treatment of DVT.

Adolescent↗
PubMed1994

Relaxation of human isolated mesenteric arteries by vasopressin and desmopressin.

1. The effects of vasopressin and deamino-8-D-arginine vasopressin (DDAVP, desmopressin) were studied in artery rings (0.8-1 mm in external diameter) obtained from portions of human omentum during the course of abdominal operations (27 patients). 2. In arterial rings under resting tension, vasopressin produced concentration-dependent, endothelium-independent contractions with an EC50 of 0.59 +/- 0.12 nM. The V1 antagonist d(CH2)5Tyr(Me)AVP (1 microM) and the mixed V1-V2 antagonist desGly-d(CH2)5D-Tyr(Et)ValAVP (0.01 microM) displaced the control curve to vasopressin to the right in a parallel manner without differences in the maximal responses. In the presence of indomethacin (1 microM) the contractile response to vasopressin was significantly increased (P < 0.01). 3. In precontracted arterial rings, previously treated with the V1 antagonist, d(CH2)5Tyr(Me)AVP (1 microM), vasopressin produced endothelium-dependent relaxation. This relaxation was reduced significantly (P < 0.05) by indomethacin (1 microM) and unaffected by the V1-V2 receptor antagonist desGly-d(CH2)5D-Tyr(Et)ValAVP (1 microM) or by NG-nitro-L-arginine methyl ester (L-NAME, 0.1 mM). 4. The selective V2 receptor agonist, DDAVP, caused endothelium-independent, concentration-dependent relaxations in precontracted arterial rings that were inhibited by the mixed V1-V2 receptor antagonist, but not by the V1 receptor antagonist or by pretreatment with indomethacin or L-NAME. 5. Results from this study suggest that vasopressin is primarily a constrictor of human mesenteric arteries by V1 receptor stimulation; vasopressin causes dilatation only during V1 receptor blockade. The relaxation appears to be mediated by the release of vasodilator prostaglandins from the endothelial cell layer and is independent of V2 receptor stimulation or release of nitric oxide. In contrast, the relaxation induced by DDAVP is largely dependent on stimulation of V2 receptors.

Adult↗
PubMed1993

Endothelium-dependent component in the contractile responses of human omental arteries to adrenergic stimulation.

The present study was designed to investigate the influence of endothelium-derived nitric oxide on the contractile responses of isolated human omental arteries to electrical field stimulation and noradrenaline. We measured isometric tension in artery rings obtained from portions of human omentum during the course of abdominal operations (32 patients). Electrical field stimulation induced frequency-dependent contractions which were abolished by tetrodotoxin (10(-6) M) and prazosin (10(-6) M), thus indicating that this effect was due to noradrenaline released from adrenergic nerves acting on alpha 1-adrenoceptors. The increases in tension induced by electrical field stimulation were of greater magnitude in arteries denuded of endothelium. NG-Nitro-L-arginine (L-NAME, 10(-4) M) potentiated the contractile response to electrical field stimulation in artery rings with endothelium but did not influence the contractile responses of endothelium-denuded arteries. The potentiation induced by L-NAME was completely reversed by L-arginine (10(-4) M), but not by D-arginine (10(-4) M). Contractile responses to noradrenaline were similar in arteries with and without endothelium. L-NAME (10(-4) M) had no significant effect on the contractile responses to noradrenaline. Our results suggest that electrical field stimulation releases endothelium-derived nitric oxide which inhibits the contractile responses of human omental arteries. The constrictor responses to noradrenaline are not modulated by the endothelium.

Adult↗
PubMed1992

Contractile response of human omental arteries to endothelin.

The effects of endothelin have been studied in isolated arterial segments (0.8-1 mm in external diam.) of human omental arteries obtained during the course of abdominal operations (15 patients, 7 men and 8 women). Paired segments, one normal and the other de-endothelized, were mounted for isometric recording of tension in organ baths. Endothelin produced concentration-dependent contractions with an EC50 value of 5.4 x 10(-9) M. Removal of endothelium did not affect significantly endothelin-induced contractions (EC50, 6.7 x 10(-9) M). Removal of extracellular calcium or addition of the calcium channel blocker nicardipine (10(-6) M) diminished but did not abolish responses to endothelin. These results indicate that endothelin exerts powerful contractile effects on human isolated omental arteries which are independent of the presence of an intact endothelial cell layer; this contraction cannot be explained solely by voltage-dependent calcium channels.

Adult↗
PubMed1991

NG-monomethyl-L-arginine and NG-nitro-L-arginine inhibit endothelium-dependent relaxations in human isolated omental arteries.

The L-arginine analogues NG-monomethyl-L-arginine (L-NMMA, 10(-4) M) and NG-nitro-L-arginine methyl ester (L-NAME, 10(-4) M), which specifically inhibit the synthesis of nitric oxide from L-arginine, significantly reduced acetylcholine-induced endothelium-dependent relaxations in rings of human omental arteries. The inhibitory potency of L-NMMA and L-NAME was similar. Addition of L-NMMA or L-NAME to the organ bath did not induce any significant changes in the resting tension of the tissues. The effects of L-NMMA were reversed by L-arginine (3 x 10(-4) M). The L-NMMA enantiomer, D-NMMA (10(-4) M), did not influence either the basal tone of the preparation or the relaxing effects of acetylcholine. Arterial relaxations induced by sodium nitroprusside (10(-6) M) were not influenced by incubation with L-NMMA or L-NAME. These results suggest that endothelium-dependent relaxations in human omental arteries are mediated by the endogenous and substrate-specific generation of nitric oxide from L-arginine.

Acetylcholine↗