Modulation of noradrenergic transmission in the rat isolated portal vein: Role of prejunctional α2-adrenoceptors and β-adrenoceptors

1. The effect of several adrenoceptor agonists and antagonists on the spontaneous and stimulus-evoked release of [3H]noradrenaline was studied in rat isolated portal vein. 2. Yohimbine (10(-6)M) increased the stimulus-evoked [3H]noradrenaline efflux. Adrenaline alone (3 x 10(-6)M) was without effect, while it increased the resting efflux when added together with yohimbine. 3. Propranolol alone was without effect on the release of [3H]noradrenaline. When added (2 x 10(-6)M) at the same time as yohimbine, it reduced the stimulation-induced 3H efflux. When added before adrenaline and yohimbine, propranolol (10(-5)M) reduced both spontaneous and stimulus-evoked release of [3H]noradrenaline. 4. The effect of several beta-blocking drugs was measured on the enhancing effect of yohimbine on the stimulation-evoked 3H efflux. The beta 1-adrenoceptor blocking drugs: atenolol (5 x 10(-6) and 10(-5) M), metoprolol (5 x 10(-6) and 10(-5) M), like the more selective bisoprolol (2 x 10(-6) and 4 x 10(-6) M) inhibited yohimbine activity. Likewise, propranolol (2 x 10(-6) and 5 x 10(-6)M) and the beta 2-adrenoceptor blocker ICI 118551 exhibited an antagonistic effect. 5. These results indicate the possibility for noradrenaline to activate presynaptic beta-adrenoceptors in rat portal vein. They show an interaction between the presynpatic alpha 2- and beta-adrenoceptor mediated systems in the release of noradrenaline. They suggest the presence and the activity of facilitatory beta 1-adrenoceptors.

Update of experience in the treatment of localized carcinoma of the prostate by definitive external irradiation

In 1987 a retrospective analysis was performed of 116 patients with carcinoma of the prostate localized to the pelvis who were treated by radiotherapy at the Northern Israel Oncology Center during the period between 1977 and 1982. It was shown that definitive external beam irradiation is an effective, simple, and easy treatment modality for localized prostatic cancer.

Uptake of 5-hydroxytryptamine in rat isolated atria

1. The mode of 5-hydroxytryptamine (5-HT) uptake by the rat isolated atria was studied and compared to noradrenaline (NA) uptake. 2. Rat isolated atria were incubated with 14C-5-HT (46 microM) or 3H-NA 0.4 microM). After washing, the radioactivity fixed in atria was counted and the total NA, 5-HT and 5-hydroxyindol-3-acetic acid (5-HIAA) atria contents were measured by HPLC. 3. 14C-5-HT uptake was reduced in atria from 6-hydroxydopamine (100 mg/kg, i.p., 48 hr before experiments) or reserpine (2.5 mg/kg, i.p., 24 and 48 hr before experiments) pretreated rats. 4. The incubation of atria with 5-HT (50 microM) at the same time as 3H-NA reduced the 3H-NA value fixed. 5. Addition of desipramine (1 microM) or hydrocortisone (150 microM) before the incubation of atria with 14C-5-HT was without any effect on 14C-5-HT uptake. In contrast, fluvoxamine (1 microM) or indalpine (5 microM) caused a slight inhibition. 6. These data indicate that 5-HT is taken into the NA storage vesicles within the atria sympathetic nerves. This uptake does not use the NA carrier and involves partly the 5-HT carrier. An extraneuronal accumulation was noticed and a part of it is intracellular.

Assembly and processing of subunit II (PsaD) precursor in the isolated photosystem-I complex

The precursor of photosystem I (PSI) subunit II (pre-subunit II) synthesized in vitro, was found to bind to the holo-PSI complex, both within the thylakoids and outside, after detergent extraction of PSI from the membranes. Chloroplast stromal fraction added to the purified PSI complexes, containing the labeled pre-subunit II, induced the processing of the precursor to the mature form. This implies that processing can occur within the isolated complex, after the integration of the precursor. The results presented suggest that certain aspects of biogenesis of membranal protein complexes can be studied in detergent-extracted purified complexes.

Autoantibodies in the sera of patients with lymphoma

Sera of 84 patients with Hodgkin's disease (HD) and 55 patients with non-Hodgkin's lymphoma (NHL) were examined for the presence of autoantibodies to ssDNA, dsDNA, Poly (I), Poly (G), cardiolipin, histones, RNP. Sm, Ro (SS/A), La (SS/B) and the common anti-DNA idiotype (16/6) using an enzyme-linked immunosorbent assay (ELISA). Anti-ssDNA antibodies were detected in the sera of 20 patients with lymphoma (23.8%), more among those with NHL than HD (16 vs. 4 patients p < 0.01). Anti-RNP and anti-Sm antibodies were found in 16 (21.7%) and 14 lymphoma patients (20%) respectively, significantly more than in the controls (p < 0.05) in both antibodies). These findings remained valid following subgrouping of the patients into those with HD and NHL. With all the other autoantibodies examined no significant difference could be observed in the incidence between lymphoma patients and controls. These results differ from our previous survey carried out on sera of patients with solid tumors in whom no increased frequency of any of the autoantibodies could be determined. In view of the evidence suggesting an increased risk of lymphoma in a number of autoimmune diseases our results extend this relationship to an increased incidence of autoantibodies among patients with lymphoma.

The value of postoperative irradiation in renal cell cancer

This is a retrospective analysis of 147 evaluable patients, with histologically proven renal cell carcinoma, who were referred to our center between 1977 through 1988. All patients with disease limited to the kidney underwent nephrectomy. Post-operative megavoltage irradiation, with a median dose of 46 Gy, was given to 56 patients, using parallel opposing portals, or multiple field technique. Five and 10 year actuarial survivals in irradiated patients (Rt+) were 50 and 44%, respectively, and in non-irradiated patients (Rt-) 40 and 32%, respectively. The disease recurred locally in a total of 19 patients; 16 had tumor bed recurrence and three had scar recurrence. Local recurrence by stage was as follows: T2 N0M0: RT+ 0/17, RT- 2/28; T3 N0M0: RT+ 4/37 (10%), RT- 11/30 (37%) (p less than 0.05); T4 N0M0: RT+ 1/2, RT- 1/5. Two of the local recurrences in irradiated patients developed in a surgical scar which was not included in the treatment volume. Significant toxicity developed in three patients (5%). It is concluded that post-operative irradiation can reduce local recurrence rate in T3 N0M0 renal cell carcinoma. It is recommended that the surgical scar should always be included in the treatment volume and irradiated to a full dose.

Effects of chloral, chloralose and pentobarbitone on monoamine and (neuropeptide Y) NPY levels in various tissues in the rat

Sampling of blood or tissues in experimental animals need frequently a general anesthesia. Some anesthetic agents are known to modify plasma levels of catecholamines; moreover NPY is co-released with noradrenaline or adrenaline under certain conditions. Thus, we investigated the effect of three general anesthetic agents, chloral, chloralose and pentobarbital (pentobarbitone) on the levels of monoamines and NPY in rat hypothalamus, medulla, atria and adrenals. Monoamines were analysed by high pressure liquid chromatography using an electrochemical detection and NPY was measured by radioimmunoassay (immunoradiometric assay, IRMA). Chloralose or pentobarbitone did not affect monoamine tissue levels. In contrast, chloral increased 5-hydroxyindolacetic acid and to a lesser extent serotonin levels in the hypothalamus. NPY tissue levels did not change whatever the anesthetic used. These results must be taken into account in pharmacological or toxicological studies which need the use of a general anesthesia.

Patterns of secretion of human chorionic gonadotrophin by superfused placental explants and the embryo--placental relationship following maternal use of medications

There is great concern regarding maternal exposure to medications, especially in the first trimester of pregnancy because of the possible teratogenic effects. In the present study we have examined the consequences of maternal drug exposure in vivo upon placental secretion patterns of human chorionic gonadotrophin (HCG) and the relationship between the embryo and placenta in vitro. This was examined in samples obtained from various drug-exposed women following elective pregnancy termination at 8-9 weeks. The patterns of HCG secretion in superfused placental explants were different from those seen in control explants (without use of any medication). This was shown by changes in the pulse pattern and pulse frequency. In addition, the exposure of placental explants to various embryonic tissues modified HCG secretion in static cultures. In superfusion, co-perfusion with embryonic spinal cord tissue increased HCG secretion as opposed to that seen in similar incubations made with embryonic spinal cord tissue obtained from healthy women. Thus, our data suggest that maternal drug exposure alters both spontaneous hormone secretion by the placenta and the recently described embryo--placental relationship in vitro.

Liposarcoma of the perineum and scrotum

A case of liposarcoma of the perineum and scrotum, which presented as a huge haematoma and was left in place for three years prior to excision, is presented. The patient was treated by wide excision of the tumour, orchiopexy to the inguinal region and radiotherapy. To date, 30 months following surgery, the patient is completely asymptomatic and no tumour recurrence is evident either on physical and rectal examinations or on chest X-rays, ultrasonography and abdominal and pelvic computerized tomography.

Stage I-II low grade non-Hodgkin's lymphoma: prognostic factors and treatment results

48 patients with stage I-II low-grade non-Hodgkin's lymphoma were treated by radiation and/or chemotherapy between 1970 and 1986. The histologic types were diffuse lymphocytic well differentiated, eleven patients; nodular lymphocytic poorly differentiated, 28 patients; nodular mixed, nine patients. Complete remission was obtained in 45 patients (94%). Overall survival was 83% and 68% at five and ten years, respectively. Five and ten-year relapse-free survival of complete responders was 71% and 57%, respectively. Univariate analysis of potential prognosticators showed the following to significantly increase the survival rate: one or two sites of disease (p less than 0.01), stage I (p less than 0.02), age less than 65 years (p less than 0.02), complete excision of tumor mass (p less than 0.03), and the use of radiotherapy (p less than 0.02). The extent of radiotherapy field did not affect survival. Multivariate analysis by the stepwise proportional hazards model of Cox showed that the use of radiotherapy was the factor which significantly produced better survival figures (p less than 0.03). It is concluded that two thirds of stage I-II low-grade lymphoma patients are potentially curable; radiotherapy plays a major role in the management.

Insertion and assembly of the precursor of subunit II into the photosystem I complex may precede its processing

The biogenesis and assembly of subunit II of photosystem I (PSI) (psaD gene product) were studied and characterized. The precursor and the mature form were produced in vitro and incubated with intact plastids or isolated thylakoids. Following import of the precursor into isolated plastids, mostly the mature form of subunit II was found in the thylakoids. However, when the processing activity was inhibited only the precursor form was present in the membranes. The precursor was processed by a stromal peptidase and processing could occur before or after insertion of the precursor into the thylakoids. Following insertion into isolated thylakoids, both the precursor and the mature form of subunit II were confined to the PSI complex. Insertion of the mature form of subunit II was much less efficient than that of the precursor. Kinetic studies showed that the precursor was inserted into the membrane. Only at a later stage, the mature form began to accumulate. These results suggest that in vivo the precursor of subunit II is inserted and embedded in the thylakoids, as part of the PSI complex. Only later, it is processed to the mature form through the action of a stromal peptidase.

MR imaging of breast hemangioma in female infants

Breast hemangioma in female infants is a rare benign lesion, prone to spontaneous regression. But when the lesion regresses there is a risk of breast atrophy if the breast bud is included in or very close to the hemangioma. A trial of corticosteroid therapy could be proposed to prevent this risk, but one must be sure that the breast bud is included in or very close to the hemangioma before treatment. We studied 4 children with breast hemangioma to evaluate the ability of MR Imaging in the diagnosis of breast bud inclusion. 0.5 Tesla axial Spin Echo T2-weighted images (TR = 2000 ms; TE = 120 ms) clearly depicted interface between high signal appearance of hemangioma and hypo-intensity of the breast bud: in our four patients we were able to determine whether or not the hemangioma involved the breast bud. Our preliminary study seems to demonstrate that MR imaging is a valuable imaging technique to determine which patients could be eligible for a trial of corticosteroid therapy.

[Patient-controlled i.v. morphine for acute postoperative pain]

The use of patient-controlled i.v. analgesia for postoperative pain relief in 60 cases is described. 0.1% morphine was given by Bard or Graseby microprocessor. After a loading dose of 2-6 mg, the pump delivered a bolus of 0.8-1.5 mg of morphine every 8-12 min. The dosages necessary to provide good analgesia varied from 30-85 mg (mean 48). Good pain scores of 0-2 (on a scale of 5) were obtained in 92%. The method was also found satisfactory by the families and health care providers, and is highly recommended for control of postoperative pain.

[Lumbar post-puncture syndrome]

About 30% of lumbar punctures are complicated by the lumbar puncture syndrome the main symptom of which is a characteristically posture-dependent headache (the so-called "spinal headache"), sometimes accompanied by nausea, vomiting and stiff neck. The syndrome usually begins in the days which follow lumbar puncture and subsides within 10 days. The most common pathogenetic theory is that perforation of the dura mater results in CSF leakage responsible for a fall in intrathecal pressure. Treatment of the lumbar puncture syndrome consists of rest in supine position and copious hydration, usually by the oral route. The epidural blood patch technique is seldom used. Prevention relies entirely on the use of small calibre lumbar puncture needles; keeping the patient lying supine after the puncture is a classical recommendation, but its preventive value has not yet been fully demonstrated.

Tolerance of low cerebral intracellular pH in rats during hyperbaric hypercapnia

BACKGROUND AND PURPOSE

Brain acidosis from cerebral ischemia is characterized by average intracellular pH levels of approximately 5.8-6.2, which appear in turn to worsen cellular injury. We report that the brain is not injured when hypercapnia is used to reduce intracellular pH to about 6.2 during adequate oxygenation. A hyperbaric chamber is needed to achieve intracellular pH values so low because inspired CO2 tensions must be increased to approximately 1 atm.

SUMMARY OF REPORT

Using in vivo phosphorus-31 and proton nuclear magnetic resonance spectroscopy, we measured brain intracellular pH and lactate concentration of rats inside a nonmagnetic polycarbonate chamber at a barometric pressure of 1,500 mm Hg. Intubated rats were ventilated with a 50% O2/50% CO2 gas mixture for specific times. All six rats ventilated for 15 minutes with CO2 tensions of approximately 750 mm Hg woke up without neurological impairment, despite a decrease in intracellular pH to about 6.2. Higher CO2 tensions and longer exposures resulted in cardiovascular collapse and sudden death, followed by the postmortem appearance of brain lactate.

CONCLUSIONS

Brain intracellular pH values near 6.2 can be induced briefly in vivo in ventilated rats without injury under hyperbaric hypercapnic conditions. If attempts are made to lower brain pH in vivo even further by increasing PCO2 beyond 750 mm Hg, mean arterial blood pressure and cerebral blood flow decrease to values incompatible with life.

Breast biopsy nuclear pellets are a convenient source of DNA for routine determination of Her-2/neu gene amplification

Cell nuclei from breast biopsies are a byproduct of routine hormone receptor determination and are usually discarded. We report here that DNA purified from this source is suitable for use in conventional Southern blot or Polymerase Chain Reaction (PCR) techniques to screen for Her-2/neu amplification, enabling efficient use of limited biopsy material.

Human embryo modulates placental function in the first trimester; effects of neural tissues upon chorionic gonadotropin and progesterone secretion

We investigated the effect of embryonal neural and adrenal tissues (7-14 weeks gestational age) upon beta hCG secretion by homologous placental explants in static and dynamic cultures. In static co-culture significant inhibition by SC and brain was noted at 7-9 weeks. Similarly, in superfusion, using a novel co-chambering technique there was a significant reduction in the area under the curve but not peak frequency of spontaneous pulsatile beta hCG secretion. Incubations with neural tissues 11 weeks and above caused a stimulatory effect upon beta hCG secretion in both models. The effect of adrenal tissue in static cultures was different, namely slightly inhibitory at 7-9 weeks and inhibitory at 11 weeks and above. In superfusion, the effect of adrenal tissue was not significant. Extracted neural tissue 7-9 weeks incubated with placental explants exhibited inhibitory effects upon beta hCG secretion as well. Buffer-based extracts of neural tissues effect was more pronounced than alcohol-based extracts regarding beta hCG secretion. The effect of extracts was dose-dependent and effects were noted up until a 2000-fold dilution. In contrast, the buffer SC extract had no effect on progesterone (P) secretion while the alcohol extract effect was inhibitory at 7-9 weeks and stimulatory at greater than 11 weeks. Superfused explants pattern of beta hCG secretion was inhibited by one minute pulse of the SC buffer extract. In conclusion, the human neural tissue of embryonal origin may modulate placental hCG and P secretion during early pregnancy.

Results of multimodal therapy in Ewing's sarcoma: a retrospective analysis of 20 patients

A retrospective analysis was performed of 20 patients with Ewing's sarcoma treated by combined modality therapy, consisting of surgery, radiotherapy, and chemotherapy. Fourteen patients (70%) achieved complete remission and 5 patients (25%) were in partial remission at the end of treatment. One patient (5%) failed to respond to combined modality therapy. The overall 5 year actuarial survival was 64% and the disease free survival, 55%. Persistent or recurrent disease occurred in 8 patients (40%); one of them was salvaged by surgery and chemotherapy. Site and extent of primary lesion were prognosticators of patients' outcome. One patient developed radiation-related-sequelae. The efficacy of aggressive management consisting of wide surgery, radiotherapy and intermittent high dose chemotherapy is discussed.

Cardiovascular effects of intracerebroventricular injections of (+/-)-nebivolol and its enantiomers--a comparison with those of metoprolol in the rat

The cardiovascular effects of (+/-)-nebivolol, a potent beta 1-adrenoceptor antagonist, and its enantiomers, (+)-nebivolol (SRRR) and (-)-nebivolol (RSSS) in normotensive anaesthetized rats, have been investigated using metoprolol as a reference substance. The drugs decreased blood pressure and heart rate immediately after i.c.v. injection. These effects paralleled the beta-blocking potencies ((+)- greater than (+/-)-greater than (-)-nebivolol). Metoprolol induced a weaker hypotension than (+/-)-nebivolol, and a long-lasting reduction in stroke volume. As reported after i.v. administration, (+/-)-nebivolol and isomers by the i.c.v. route decreased peripheral vascular resistance following i.c.v. administration while metoprolol increased it. These effects are centrally mediated since cardiovascular responses to isoprenaline i.v. remained unchanged.

[Primary brain lymphoma]

Between 1973 and 1989, 739 patients with non-Hodgkin's lymphoma were referred here for treatment, of whom 10 (1.4%) had primary brain lymphoma (PBL) and 1 had acquired immunodeficiency syndrome (AIDS). There were 7 females and 3 males (mean age 58 years, range 35-77). Duration of symptoms ranged from several days to 3 weeks. The presenting symptoms were secondary to increased intracranial pressure. Computerized tomography (CT) performed in 8 revealed a solitary lesion in 7. Other CT scan features were various degrees of contrast enhancement, edema and midline shift. The most common site was the frontal lobe; infratentorially, the cerebellum was the most frequent site. The diagnosis was established in 8 patients by surgery and in 2 at autopsy. The most common subtype was the diffuse, large cell, immunoblastic lymphoma. 5 patients were irradiated following subtotal excision and 2 had combined radiation therapy and high-dose methotrexate-based chemotherapy; only 1 had no postoperative treatment. All patients treated by radiotherapy alone died within 3-5 months after diagnosis. The 2 who received combined therapy are alive, 15 and 48 months after diagnosis, respectively.

On some of the in organello processes involved in the biogenesis of chlorophyll-protein complexes

The biogenesis and assembly of chlorophyll-protein complexes consist of many steps. These are initiated with the transcription and translation of the different polypeptide components constituting the complexes. For the nuclear-encoded subunits the synthesis takes place in the cytoplasm, and they are synthesized as precursors, which are later imported into the chloroplast. Within the organelle, the precursors are inserted into the thylakoid membranes, as well as being processed to their mature forms. The different nuclear- and chloroplast-encoded subunits assemble together, and bind the pigments and other cofactors to form the active pigmented-complex. In the present article, we discuss only the in organello processes of the biogenesis. We describe the pathways taken by two nuclear-encoded thylakoid proteins, the precursor of the main light-harvesting chlorophyll-protein of photosystem II (pLHCP) and the precursor of photosystem I subunit II (pre subunit II). These polypeptide subunits, that are located in two different photosynthetic complexes, differ from each other. While pLHCP is an integral membrane protein, which binds pigments, photosystem I-subunit II is a peripheral membrane protein, located on the stromal side of the thylakoids, and is not predicted to span it. The differences and the common features of the in organello biogenesis pathways of these two proteins are discussed.

Effects of dexfenfluramine and opioid peptides, alone or in combination, on food intake and brain serotonin turnover in rats

Dexfenfluramine (d-FF) and opiate agonists both act on food intake but in opposite ways. Serotonin is known to be involved in the pharmacological action of both d-FF and opiates, but not necessarily in the feeding effect of the latter. In order to test this hypothesis, the effects of three opioid agonists, beta-endorphin, dynorphin and D-Ser2-Leu-Enk-Thr6 (DSLET) and of an antagonist, naltrexone, were investigated individually and in combination with d-FF on food intake and brain serotonin turnover. The opioid agonist-d-FF combinations generally produced a similar anorectic effect to that of d-FF alone, with the exception of DSLET which showed a reciprocal antagonism. The serotonergic effects varied according to the opioid tested, alone or in combination with d-FF. This does not allow to highlight a general pattern of serotonin involvement in the feeding effects of these peptides. However, all the treatments which decreased feeding (d-FF, naltrexone and the combinations dynorphin-d-FF and beta-endorphin-d-FF) displayed similar trends in hypothalamic serotonergic variations. This study evidences a role of serotonin in the feeding effect of opiates, although not similar for all of them. The use of d-FF provides a tool for assessing this involvement.