Endothelin-A receptor antagonist inhibits angiotensin II and noradrenaline in man

AIMS: Endothelin-1 (ET-1) is a potent vasoconstrictor produced by the vascular endothelium. The interactions of ET with the mediators of the sympathetic nervous system and the renin-angiotensin-system in humans are unclear. METHODS: We studied the effects of the ETA-selective antagonist BQ-123 and the ETB-selective antagonist BQ-788 (both 10(-10)-10(-8) M) on ET-1 (10(-16)-10(-10) M), angiotensin II (AT, 10(-16)-10(-10) M) and noradrenaline (NA, 10(-16)-10(-10) M) induced vasoconstriction in the human skin microcirculation in vivo in 25 healthy male volunteers using laser Doppler flowmetry and double injection technique. RESULTS: BQ-123 caused a dose-dependent vasodilatation (maximum effect: + 949 +/- 84 AUC-PU, P < 0.001), whereas BQ-788 induced mild vasoconstriction (maximum effect: -388 +/- 96 AUC-PU, P < 0.01). In the presence of BQ-123, but not BQ-788, ET-1, AT and NA caused markedly less vasoconstriction at any tested agonist dose; the effect was most pronounced on ET-1 (maximum effect at 10(-14) M: + 814 +/- 93 AUC-PU vs ET alone, P < 0.001), followed by noradrenaline (maximum effect at 10(-16) M: +580 +/- 107 AUC-PU vs NA alone, P < 0.01) and angiotensin II (maximum effect at 10(-14) M: + 493 +/- 111 AUC-PU vs AT alone, P < 0.001). CONCLUSIONS: ETA-selective antagonism inhibits vasoconstriction to AT and NA in vivo in healthy subjects. This beneficial effect may be useful for the treatment of patients with cardiovascular disease including hypertension especially in combination therapy with sympatholytic agents and inhibitors of the renin-angiotensin system.     

Unexpected severe myelotoxicity of gemcitabine in pretreated breast cancer patients

Gemcitabine is a chemotherapeutic agent with proven antitumor effects in pancreatic and non-small cell lung cancer; however, studies establishing the definite significance in other solid tumors are still in progress. We herein present three female patients with advanced breast cancer who received gemcitabine as salvage chemotherapy. Gemcitabine at a dose of 1250 mg/m2 was scheduled for days 1, 8 and 15 with a subsequent rest for 1 week. However, within 1 week after the very first administration of gemcitabine myelotoxicity WHO grade IV occurred in all patients, leading to discontinuation of therapy. In two patients this gemcitabine-induced hematotoxicity could be overcome by means of vigorous supportive care, but one patient died after cerebral bleeding due to severe thrombocytopenia. We conclude that gemcitabine in heavily pretreated breast cancer patients should only be used with extreme caution with special focus on platelet counts until solid data from clinical studies for doses and schedules are available.     

Haemodynamic characterization of young normotensive men carrying the 825T-allele of the G-protein beta3 subunit

A C825T polymorphism was recently identified in the gene for the G-protein beta3 subunit, the T-allele being associated with hypertension. To better understand the underlying pathophysiological mechanisms, we compared the haemodynamics of young healthy males with and without the T-allele. In three studies, subjects were investigated with regard to cardiac and vascular function at rest and following intravenous administration of the beta-adrenoceptor antagonist, propranolol, and the alpha2-adrenoceptor agonist, alpha-methylnoradrenaline, and with regard to local venous vasoconstriction in the dorsal hand vein in situ following infusion of the alpha2-adrenoceptor agonist, azepexol. alpha2-Adrenoceptor agonists were chosen as vasoconstrictor drugs since alpha2-adrenoceptors couple to pertussis toxin (PTX)-sensitive G-proteins and since in-vitro studies have demonstrated enhanced signal transduction of PTX-dependent pathways in the presence of the T-allele. Total peripheral resistance was determined as a parameter of vasoconstrictor tone and heart rate, stroke volume and systolic time intervals for cardiac function. T-allele carriers had a significantly elevated stroke volume and lower total peripheral resistance at baseline. After propranolol, their fall in stroke volume was significantly greater. During alpha-methylnoradrenaline infusion, elevation of total peripheral resistance was not increased relative to controls. Similarly, the constriction response of the dorsal hand vein to azepexol was not different. Our study does not support the idea of increased vasoconstrictor tone in T-allele carriers either at rest or during stimulation of alpha2-adrenoceptors. However, this allele may be associated with elevated cardiac stroke volume.     

Docetaxel monotherapy in heavily pretreated metastatic breast cancer: a multicenter, community-based feasibility trial

PURPOSE: To evaluate the efficacy and safety of docetaxel in heavily pretreated and anthracycline-resistant patients with metastatic breast cancer in an outpatient setting. PATIENTS AND METHODS: Between February 1996 and June 1998, 98 consecutive patients who had progressed during or relapsed following prior anthracycline-containing chemotherapy were enrolled into the trial. Docetaxel was administered at a dose of 100 mg/m2 by intravenous infusion every 3 weeks. The administration of colony-stimulating factors was at the discretion of the attending physician. Premedication with dexamethasone was mandatory for all patients. RESULTS: Of the 98 patients, 93 were evaluable for toxicity and response. Patients had received two palliative regimens (median, range 1-5) prior to docetaxel treatment. The most frequent toxicity observed was leukopenia grade III and IV (WHO grading system) which occurred in 47% of patients (grade IV only in 14%). Except for alopecia grade III (64% of patients), nonhematologic side effects grade III-IV were rare (1-7% of patients) and included nausea, stomatitis, diarrhea, peripheral neuropathy, fluid retention and pulmonary toxicities. There were no treatment-related deaths. Objective responses occurred in 40% of patients (CR 6%, PR 34%), and stable disease in 38% of patients. The median duration of response was 5.3 months (range 0.7-18.1 months) while the median survival was 15 months (range 2 36 months). CONCLUSION: Docetaxel is a highly active agent in patients with anthracycline-resistant metastatic breast cancer, even in heavily pretreated patients, with moderate toxicity.     

Serotonin transporter gene regulatory region polymorphism (5-HTTLPR), [3H]paroxetine binding in healthy control subjects and alcohol-dependent patients and their relationships to impulsivity

The aim of this study was to investigate [3H]paroxetine binding and impulsivity in alcohol-dependent and age-matched control subjects in relation to a 5'-promoter region serotonin transporter (5-HTT) polymorphism (5-HTTLPR). Alcohol-dependent subjects were hypothesized to show a decreased number of bindings sites and a lower dissociation constant. 5-HTTLPR S-genotype carriers in both alcohol-dependent and control subjects were expected to show significantly fewer binding sites and a lower dissociation constant. Influences of impulsive traits, chronic daily alcohol intake, duration of alcohol dependence, age of onset and age on [3H]paroxetine binding were also investigated. Inpatients meeting DSM IV alcohol dependence criteria and of German descent were recruited to avoid ethnic stratification effects. One hundred and seventeen control subjects of similar social status were recruited from a town community. Blood samples were taken from both alcohol-dependent and control subjects to determine 5-HTTLPR genotypes using PCR of lymphocyte DNA, and to perform platelet [3H]paroxetine binding (binding capacity: B(max); and dissociation constant: K(D)). Impulsivity was assessed using the Barratt impulsiveness scale version 5 (BIS-5) in alcohol-dependent subjects only. Alcohol-dependent subjects were subdivided into low or high impulsivity groups using a median-split of the BIS-5 scale. The control group was slightly older than the alcohol-dependent group (not statistically significant). [3H]paroxetine binding was investigated in 72 control subjects and 72 patients, of which five patients met type 2 alcohol dependence criteria. Genotyping was carried out in all patients and control subjects. A significant influence of duration of alcohol dependence was found on the [3H]paroxetine binding K(D) but not B(max.) Neither alcohol-dependent nor control subjects showed any differences in B(max) or K(D). S-allele carriers did not show a decreased binding or lower dissociation constant. Furthermore, no significant interaction between B(max) and K(D) with either 5-HTTLPR genotype or impulsivity was revealed. This was the first study to investigate platelet [3H]paroxetine binding in alcohol-dependent and age-matched control subjects in relation to the 5-HTTLPR genotype. No differences concerning 5-HTTLPR-alleles were found in these groups Furthermore, no significant interaction between these parameters and impulsivity was shown in alcohol-dependent subjects. These results do not support previous results of altered [3H]paroxetine binding sites in alcohol-dependent subjects or 5-HTTLPR S-allele carriers. K(D) might be influenced by duration of alcohol dependence, but not sufficiently to yield differences between alcohol-dependent and control subjects.     

Vasopressin During Cardiopulmonary Resuscitation and Different Shock States

Vasopressin administration may be a promising therapy in the management of various shock states. In laboratory models of cardiac arrest, vasopressin improved vital organ blood flow, cerebral oxygen delivery, the rate of return of spontaneous circulation, and neurological recovery compared with epinephrine (adrenaline). In a study of 1219 adult patients with cardiac arrest, the effects of vasopressin were similar to those of epinephrine in the management of ventricular fibrillation and pulseless electrical activity; however, vasopressin was superior to epinephrine in patients with asystole. Furthermore, vasopressin followed by epinephrine resulted in significantly higher rates of survival to hospital admission and hospital discharge. The current cardiopulmonary resuscitation guidelines recommend intravenous vasopressin 40 IU or epinephrine 1mg in adult patients refractory to electrical countershock. Several investigations have demonstrated that vasopressin can successfully stabilize hemodynamic variables in advanced vasodilatory shock. Use of vasopressin in vasodilatory shock should be guided by strict hemodynamic indications, such as hypotension despite norepinephrine (noradrenaline) dosages >0.5 mug/kg/min. Vasopressin must never be used as the sole vasopressor agent. In our institutional routine, a fixed vasopressin dosage of 0.067 IU/min (i.e. 100 IU/50 mL at 2 mL/h) is administered and mean arterial pressure is regulated by adjusting norepinephrine infusion. When norepinephrine dosages decrease to 0.2 microg/kg/min, vasopressin is withdrawn in small steps according to the response in mean arterial pressure. Vasopressin also improved short- and long-term survival in various porcine models of uncontrolled hemorrhagic shock. In the clinical setting, we observed positive effects of vasopressin in some patients with life-threatening hemorrhagic shock, which had no longer responded to adrenergic catecholamines and fluid resuscitation. Clinical employment of vasopressin during hemorrhagic shock is experimental at this point in time.     

Prognostic value of monitoring tumour markers CA 15-3 and CEA during fulvestrant treatment

Background  

At many centres tumour markers are used to detect disease recurrence and to monitor response to therapy in patients with advanced disease, although the real value of serial observation of marker levels remains disputed. In this study, we evaluated the prognostic value of tumour markers for predicting response (partial response [PR], stable disease [SD] ≥ 6 months), de novo disease progression (PD) and secondary PD in patients receiving fulvestrant ('Faslodex') 250 mg/month for the treatment of metastatic breast cancer (MBC).     

Supportive care for women with gynecologic cancers

Supportive care is a multidimensional field, that involves caring for a patient's symptoms either during and/or after treatment. Ideally, once these supportive care needs are met, patients can enjoy an improved quality of life. Supportive care needs include all body systems, and are, therefore, difficult to manage, secondary to the fact that they require collaboration among multiple medical specialties. In this review, several components of supportive care are separated into two categories: tumor-related morbidities and treatment-related morbidities. Some of the themes discussed include nausea and vomiting, cancer pain, psychological distress, fatigue and anemia, small bowel obstruction and peripheral neuropathy. While all of these components are challenging to manage, it is perhaps the psychosocial realm that remains the most unmet need. Regardless, the oncologist must act as a facilitator who addresses these needs and, if unable to address the issue alone, knows how to steer the patient toward the appropriate provider. As these needs are met, the goal is for quality of life to improve; and with the improvement in quality of life we may expect to see improved survival outcomes.     

Sialendoscopy of the salivary glands

INTRODUCTION: Sialoendoscopy is a simple efficient mode of treatment for major salivary gland sialoliths and strictures. METHODS: Sialendoscopy procedure requires specific devices, diagnostic and therapeutic sialendocopes, minigrasping forceps, wire baskets, lasers, balloons and stents. The sialendoscopy procedure is divided in three steps: the duct introduction step (through the papilla or through the duct wall); the diagnostic step (from main duct to third or fourth salivary division branches) and the therapeutic step (stone removal with a Dormia basket or miniforceps and stenosis balloon dilatation). The feasibility of stone removal depends on the size, the position, the mobility and the shape of the stone. The only contraindication is acute sialadenitis. DISCUSSION: Sialendoscopy complications are minor. Its success rate for stone removal is greater than 90%, and it has dramatically reduced the rate of sialadenectomy (to less than 5%).