Interrelationships of endoplasmic reticulum, mitochondria, intermediate filaments, and microtubules--a quadruple fluorescence labeling study.

To study the interrelationships of endoplasmic reticulum, mitochondria, intermediate filaments, and microtubules, we have developed a quadruple fluorescence labeling procedure to visualize all four structures in the same cell. We applied this approach to study cellular organization in control cells and in cells treated with the microtubule drugs vinblastine or taxol. Endoplasmic reticulum was visualized by staining glutaraldehyde-fixed cells with the dye 3,3'-dihexyloxacarbocyanine iodide. After detergent permeabilization, triple immunofluorescence was carried out to specifically visualize mitochondria, vimentin intermediate filaments, and microtubules. Mitochondria in human fibroblasts were found to be highly elongated tubular structures (lengths up to greater than 50 microns), which in many cases were apparently fused to each other. Mitochondria were always observed to be associated with endoplasmic reticulum, although endoplasmic reticulum also existed independently. Intermediate filament distribution could not completely account for endoplasmic reticulum or mitochondrial distributions. Microtubules, however, always codistributed with these organelles. Microtubule depolymerization in vinblastine treated cells resulted in coaggregation of endoplasmic reticulum and mitochondria, and in the collapse of intermediate filaments. The spatial distributions of organelles compared with intermediate filaments were not identical, indicating that attachment of organelles to intermediate filaments was not responsible for organelle aggregation. Mitochondrial associations with endoplasmic reticulum, on the other hand, were retained, indicating this association was stable regardless of endoplasmic reticulum form or microtubules. In taxol-treated cells, endoplasmic reticulum, mitochondria, and intermediate filaments were all associated with taxol-stabilized microtubule bundles.


Inhalant allergens in asthmatic children in Taiwan: comparison evaluation of skin testing, radioallergosorbent test and multiple allergosorbent chemiluminescent assay for specific IgE.

The multiple allergosorbent chemiluminescent assay (MAST-CLA) is a method for measuring total and allergen-specific IgE in human serum by a chemiluminescent immuno-enzymatic system. To compare the results of MAST tests with those of radioallergosorbent (RAST) and skin tests as an adjunct to the diagnosis of inhalant allergens in Taiwan, 195 asthmatic children, aged 5 to 15 years, were studied. All MAST tests had valid positive and negative control threads. The most important allergens in our patients were the two mite species: Dermatophagoid pteronyssinus and Dermatophagoid farinae (87.5% and 82.1%, respectively). There were also large responses (MAST-CLA class > or = 2) to the cockroach mix (28.45%), Alternaria (24.3%), and Eucalyptus (32.6%). The individual efficiency percentage between MAST-CLA and skin tests was D. pteronyssinus 91%, D. farinae 88%, cockroach mix 85%, feather mix 75%, dog dander 64%, Candida 75%, Aspergillus 79%, Alternaria 88%, ragweed mix 62% and Eucalyptus 76%. Comparison of the results of allergen-specific IgE measured by MAST-CLA and RAST were also significantly correlated for all four allergens (D. farinae, Candida, Alternaria and grass mix, r = 0.79-0.92). MAST-CLA was randomly duplicated and proven reproducible in 89% of the tests. Changes between positive and negative results occurred in only 3.6% of the tests. MAST-CLA is a simple in vitro test for specific IgE to 35 allergens, which compares favorably with RAST. It is concluded that MAST-CLA and RAST are similar in their ability to measure allergen-specific IgE, and correlate equally well with skin tests and clinical history in asthmatic children.


Body axis determination during early development in amphibians.

The specification of the main axes of the body is a phenomenon based on cell communication and is among the early crucial events of embryonic development. Upon fertilization, the amphibian egg reorganizes its cytoplasmic content, leading to the establishment of the future dorsal-ventral axis of the body. Heterogeneous distribution of maternal components confers cellular regionalization after only a few mitoses. Development up to the 4000-cell stage proceeds almost entirely on maternal materials, and during this period there is remodeling of the chromatin to set up specific gene expression in various regions of the embryo. The zygote at this stage has already undertaken cellular interactions leading to mesoderm formation and regionalization. Dorsal mesodermal components then induce the formation of the Spemann's organizer, a structure directly involved in the specification of the anterior-posterior axis of the embryo (head to tail). Molecular analysis of these phenomena has allowed the identification of growth-factor-like and transcription-factor-like proteins that have characteristics typical of specification factors. We will review the recent advances on these molecules and will also discuss the putative role of retinoic acid as a posteriorizing agent.


The effect of alpha-2 agonists and antagonists on the upper urinary tract of the rat.

We examined the effect of the selective alpha-2 agonist dexmedetomidine and antagonist atipamizole on the upper urinary tract, renal pelvic pressure and ureteral peristalsis. Experiments were performed on twelve Sprague-Dawley female rats weighing 275-323 grams, with administration of urethane (1.2 micrograms/kg). Ventilatory support was provided through a tracheotomy. A continuous normal saline infusion was maintained through the left iliac vein at a rate of 2.5 ml/hr. Arterial pressure was measured at the left iliac artery, which was cannulated with a PE-100 tube connected to a pressure transducer. A mid-line incision was then made from the xyphoid to the symphysis to expose the left kidney, both ureters, and the bladder. The bladder was intubated and drained to avoid bladder pressure increase. Measurements of urine output rate were made from the right ureter and renal pelvic or ureteral pressure was measured using a nephrostomy placed into the pelvis. A ureterostomy was produced by introducing another catheter, into the upper segment of the left ureter for ureteral pressure measurements. The rats were divided into two groups as follows: 1) dexmedetomidine group (n = 6); injected intravenously with 2 micrograms/kg of dexmedetomidine dissolved in 0.5 ml saline. 2) atipamizole group (n = 6); injected intravenously with 2 micrograms/kg of atipamizole dissolved in 0.5 ml saline. Ureteral peristaltic frequency, baseline pressure, and contraction amplitude were compared before, after, and between the bolus injections of 2 micrograms/kg dexmedetomidine (n = 6) or 2 micrograms/kg atipamizole (n = 6) in 0.5 ml saline. The results showed that dexmedetomidine at 2 micrograms/kg produced a significant decrease in arterial pressure and an increase in urine output from 1.2 + 0.8 to 3.6 + 1.2 ml/min. There was no effect on the baseline pelvic pressure of 6.8 + 1.2 cmH2O or amplitude of the renal pelvic contractions: 3.5 + 0.6 cmH2O. The frequency of pelvic contractions was reduced from 0.37 + 0.03 to 0.27 + 0.02 Hz. Atipamizole at 2 micrograms/kg produced a significant reduction in urine flow rate of 1.1 + 0.8 to 0.6 + 0.2 ml/min. Atipamizole also showed no significant effects on baseline pelvic pressure or frequency, but increased the amplitude of pelvic contractions from control values of 3.0 + 0.9 to 3.4 + 0.9 cmH2O. Dexmedetomidine reduced both the baseline ureteral pressure of 8.5 + 2.4 and peristaltic contraction pressure of 11.5 + 2.3 cmH2O in 4/6 rats. Atipamizole reduced base-line ureteral pressure and increased peristaltic rate.(ABSTRACT TRUNCATED AT 400 WORDS)


Blood levels of platelet-activating factor in endotoxin-sensitive and endotoxin-resistant mice during endotoxemia.

Platelet-activating factor (PAF) is a phosphoglyceride secreted by a variety of cells and has been implicated in endotoxin toxicities. To further confirm its role in endotoxin-induced tissue injuries and death, we conducted an experiment on endotoxin-resistant (C3H/HeJ strain) and endotoxin-sensitive (C3H/HeN strain) mice. The experiment consisted of three parts: 1) the LD50 of endotoxin from E. coli 0127:B8 cells was quantitated in C3H/HeN mice; 2) the lethality of PAF in C3H/HeJ mice at a dose lethal to C3H/HeN mice was determined; and 3) the blood levels of PAF in C3H/HeJ and C3H/HeN mice were measured after a dose of endotoxin lethal to the C3H/HeN strain was injected. PAF contained in the blood samples was extracted by a solid phase procedure and assayed by a radioimmunoassay method. The results showed that endotoxin-resistant and endotoxin-sensitive mice were equally susceptible to death induced by the same lethal dose of PAF. After injection with endotoxin, the blood PAF levels in C3H/HeN mice increased significantly (p < 0.01) at 60 minutes and 90 minutes, with a peak level three times that of the control group. The blood PAF levels in C3H/HeJ mice, however, remained unelevated throughout the experiment. The timing of the occurrence of the peak blood PAF level in the C3H/HeN mice corresponded with the emergence of their illness from the endotoxin injection. These findings shed new light on our understanding of the resistant mechanisms of C3H/HeJ mice to bacterial endotoxin and affirm the possible role of PAF in mediating endotoxin toxicities.


Occupational exposure and respiratory morbidity among asbestos workers in Taiwan.

To determine the prevalence of asbestos-related lung disease and the impairment of lung function among asbestos workers, we conducted a cross-sectional health survey of 459 workers in 33 asbestos-related factories in Taiwan. Each worker was asked about his medical and occupational history and was given a medical examination, chest roentgenogram and pulmonary function test. Manufacturing processes included production of asbestos cements, textiles, friction materials and insulation products. Exposure assessments were based on asbestos sampling and counting using a phase contrast microscope. The average age of the participants in the study was 41.6 years. They had an average of 8.1 years of dust exposure, with a range of one to 42 years. The majority had a cumulative asbestos exposure of less than 20 fiber years/mL. No case of asbestos-related lung disease was found during our investigation. No roentgenogram showed unequivocal changes of asbestosis. However, a multiple linear regression analysis of the pulmonary function test showed that both FVC and FEV1 decreased significantly with an increasing cumulative dose of exposure after controlling for age, height and smoking effects during analysis. FEV1/FVC and FEF25-75% were not affected by exposure dose. The absence of asbestosis and other asbestos-related lung diseases may be due to an inadequate induction time of asbestos exposure and a possible healthy selection of workers. We conclude that among workers in Taiwan, there is a significant effect on the respiratory system, especially pulmonary function, due to asbestos exposure.


Relationships between age, sex, anthropometry and bioelectrical impedance.

To establish the relationships between age, sex, anthropometric measurements and bioelectrical impedance, 446 healthy subjects (242 men and 204 women), aged 17 to 88 years, were enrolled in our study. Anthropometric parameters included body weight, height, body mass index (BMI), skinfold thickness of the triceps (TSF), and arm muscle circumference (AMC). Using the BIA-106, RJL System, the bioelectrical resistance, bioelectrical reactance and phase angle were measured. Correlation analysis revealed a significant correlation between gender, anthropometry and bioelectrical resistance. A significant correlation between age, anthropometry and reactance was also noted. Both male and female subjects in the fourth quartile of the age distribution showed significantly lower reactance and phase angle. The quartile study of the body mass index revealed corresponding changes in weight, BMI, TSF, AMC and resistance in quartiles, but not reactance. In conclusion, in addition to anthropometry, gender has an effect on bioelectrical resistance, and age has an effect on reactance.


Mortality trends of pancreatic cancer: an affluent type of cancer in Taiwan.

Interest in the increasing trends in pancreatic cancer mortality in Taiwan has recently emerged. The mortality data for pancreatic cancer in Taiwan from 1971 to 1988 for both sexes are presented to cast some light on the etiology of this ominous and yet little-known disease. A steeply increasing trend was found between 1975 and 1984 for both sexes; it dropped in 1985-86 and climbed again in 1987-88. The urban excess risks persisted in our study period of 18 years. Further study is mandatory to elucidate the etiological implications of dietary and other lifestyle changes on the magnitude of these rising secular trends and urban-rural gradients, particularly in the elderly, as well as the puzzling finding of cross-sectional drops in mortalities between 1985 and 1986. It is speculated that the drop may be associated with an economic recession that occurred in Taiwan between 1980 and 1981.


[Hypertension and arteriosclerosis].

Arterial hypertension is a major risk factor for atherosclerosis. The mechanisms involved include elevation of blood pressure, increased velocity of the sphygmic wave and increased blood flow turbulence. These hemodynamic features however do not fully explain the link between hypertension and atherosclerosis. An important role is also played by humoral factors including catecholamines, the renin-angiotensin-aldosterone system, serotonin, endothelin, platelets and endothelium-derived growth factors. Furthermore in the last few years great relevance has been attributed to hyperinsulinemia (accompanied by hypercholesterolemia and hypertriglyceridemia) that is frequently found in hypertensive subjects. Several recent reports on the antiatherogenic effect of some antihypertensive agents that could slow down the progression of atherosclerotic lesions in hypertensive subjects are promising.


Expression of alpha 6 beta 1 integrin, the laminin receptor, on subsets of normal murine lung fibroblasts and its upregulation by the inflammatory cytokines IFN-gamma and TNF-alpha.

The purpose of this investigation was to ascertain whether the alpha 6 integrin subunit was present on normal murine lung cells and fibroblasts, and if so, to determine the identity of the beta subunit coordinately expressed with alpha 6 and whether or not these integrin subunits could be regulated by cytokines. Previously, our laboratory isolated populations of Thy 1+ and Thy 1- fibroblasts from normal murine lung tissue. These cells differed in surface marker expression and in response to, and production of, pro-inflammatory cytokines. Research defining the properties of these two populations has led to the hypothesis that unique groups of fibroblasts exist within the murine lung. Though alpha 6 beta 1 is known to be expressed by platelets, lymphocytes, and epithelial cells, its presence and regulation on lung fibroblast subsets has not been explored. We now report the following findings: 1) the laminin receptor, alpha 6 beta 1, is present on 20-30% of freshly isolated normal murine lung cells in all three murine strains tested; 2) established Thy 1+ and Thy 1- murine lung fibroblast subsets and clones constitutively express alpha 6 beta 1 at varied levels; and 3) alpha 6 beta 1 expression on fibroblast lines and clones can be upregulated by treatment with IFN-gamma or TNF-alpha. Since these T cell and macrophage derived cytokines are known to be present during an inflammatory response, upregulation of alpha 6 beta 1 expression may facilitate recruitment and retention of lung fibroblasts in regions undergoing repair.(ABSTRACT TRUNCATED AT 250 WORDS)


Surgical management of Graves' ophthalmopathy: stage I, inferomedial orbital decompression.

Inferomedial orbital decompression was done on 26 eyes with dysthyroid optic neuropathy (DON), seven eyes with corneal exposure which had not responded to topical lubricants, and six with disfiguring exophthalmos. Twenty-one of the 26 DON eyes (80.7%) had visual acuity improvement equal to or greater than two lines by the Snellen chart, and there was only one in all 39 eyes that dropped more than two lines. The average retinal sensitivity improvement was of borderline significance (4.25 +/- 5.73 dB), but for those 13 severely affected eyes (preoperative sensitivity loss > or = 10 dB), 11 (84.6%) of them showed significant improvement. There were 16 bilateral and seven unilateral cases. Out of all 39 eyes, the average retroplacement effect was 4.6 +/- 2.3 mm, and none of them had postoperative asymmetry greater than 2 mm by Hertel's exophthalmometry. Although the palpebral fissure height tends to remain the same after surgery, upper lid retraction is likely to be worse. The most frequent sequela was diplopia, which tended to occur in more severely myopathic eyes regardless of the surgical approach used. Although a staged approach is mandatory in surgical treatment of this disorder, individualization of surgical goals and intraoperative titration of the retroplacement effect are of equal importance for optimal results.


[New aspects of therapy in hemicrania].

Within the pharmacological treatment of migraine it is possible to distinguish treatment of attacks and prevention therapy. The aim of attack treatment is to stop pain and accompanying symptoms, or at least to make them more tolerable, whereas the aim of prophylaxis is to reduce the frequency and possibly the severity and duration of the residual episodes. The choice to initiate either treatment, or both, is based on quantitative criteria, such as attack frequency (if greater than 2-3 per month, prophylaxis treatment is recommendable) and on qualitative features, like the degree of disability, the response and the tolerance of the patient to attack treatment. Prophylaxis treatment has not achieved any improvement since 1981, when propranolol was first utilized. The knowledge of the mechanisms of action of drugs used in prophylaxis, as well as their results, are at a standstill. Even with the newer calcium channel antagonists and beta-blockers we achieve a 50% reduction of attacks in less than half of subjects treated. On the other hand, we had important news in the treatment of migraine attacks. Sumatriptan, a selective agonist of serotonin receptors, represents a therapeutic novelty due both to the results obtained and to the studies that have been stimulated on the pathogenesis of migraine. New therapeutic perspectives are now opening and hopefully thanks to the cooperation of basic and clinical scientists, they might become a reality in a short time.


Chromosomal screening of mentally retarded school children in Taipei.

The major concern of the national population policy in Taiwan in recent years has been to lower the incidence of hereditary diseases and mental retardation in the general population. It has been estimated that there are around 10,000 mentally retarded school children in Taiwan. If effective chromosomal screening can be extended to these children, some of the family members who are carriers of balanced chromosomal rearrangements may benefit from follow-up studies and genetic counseling. The present report is the result of a pilot study conducted from 1988 to 1991 to explore the possibility of chromosomal screening of mentally retarded school children in Taipei. A total of 871 blood samples were collected from 1,147 children registered in 46 schools or residing in homes for the retarded. Chromosomal analysis was successfully accomplished on 674 out of 871 blood samples. The following chromosomal abnormalities were observed: 28 Down's syndrome, four Klinefelter syndrome, one XYY, one triple X, 11 translocations, seven inversions, four mosaics, three duplications, one deletion and one with an extra marker chromosome. After follow-up cytogenetic analyses of 13 families with probands with structural chromosomal anomalies, three of these families were shown to have one or two carriers of balanced translocated chromosomes. It seems that the present screening system would not be practical or cost-effective if it were applied island-wide in the future.


Experimentally induced axial dysraphism and anorectal malformation in male rat fetuses by intragastric administration of ethylenethiourea.

Pregnant Sprague Dawley rats were separated into two groups. In the experimental group, single intragastric doses of ethylenethiourea (ETU) were given on the 11th day of gestation. In the control group, a single intragastric dose of distilled water was given on the same day of gestation. Fetuses were recovered on day 20 of gestation, and were prepared for dissection and light microscopy. A high incidence of axial dysraphic disorders (omphalocele and rachischisis) and imperforate anus with recto-urethral fistula were noted in experimental male rat fetuses obtained from dams subjected to varying doses of ETU.


Xanthomonas maltophilia bacteremia: an analysis of 32 cases.

Thirty-two cases of Xanthomonas maltophilia bacteremia have been identified over the last two years at the Veterans General Hospital, Taipei. Among them, 27 cases (84%) were due to hospital-acquired infections, and 14 cases (44%) were polymicrobial bacteremia. One case was confirmed as prosthetic valve endocarditis and one case was complicated by recurrent attacks of ecthyma gangrenosum. Most cases had severe debilitating conditions. Twelve cases (38%) had a malignancy, 19 cases (59%) were resident in the Intensive Care Unit and 16 cases (50%) had undergone major surgery. The main predisposing factors included central venous catheterization, endotracheal intubation or tracheostomy, prior antibiotic therapy and prolonged hospitalization. Moxalactam, chloramphenicol and trimethoprim-sulfamethoxazole were the most effective agents in vitro against X. maltophilia. Twenty-two cases (69%) died during hospitalization; 13 cases (41%) were directly attributed to septicemia. Factors that adversely influenced mortality included inappropriate antimicrobial therapy and prior antibiotic treatment. Of particular interest is the fact that none of the patients who did not receive appropriate antimicrobial therapy survived. Early diagnosis and appropriate antibiotic therapy are critical for improving the prognosis of X. maltophilia infection.


Effect of food on pharmacokinetics of cefuroxime axetil in Chinese subjects.

The effect of food on the pharmacokinetics of cefuroxime axetil was studied. Twelve healthy male subjects were included in this study. They were given single oral 500 mg doses of cefuroxime axetil alone or with food based on a balanced two-way crossover design. Plasma cefuroxime concentrations were assayed by the high performance liquid chromatographic method. When the drug was given alone, the area under the curve (AUC) was 15.77 +/- 4.12 mg*h/L, Cmax was 4.20 +/- 1.05 mg/L, Tmax was 2.36 +/- 0.84 h, T1/2 was 1.56 +/- 0.26 h, and Clp/F was 34.13 +/- 10.39 L/h; 45.12 +/- 9.59% of the dose was recovered in the urine within 24 hours, and the renal clearance was 12.58 +/- 4.41 L/h. When the drug was given with food, the corresponding AUC was 23.46 +/- 4.57 mg*h/L, Cmax was 7.10 +/- 1.41 mg/L, Tmax was 2.04 +/- 1.32 h, T1/2 was 1.40 +/- 0.23 h, and Clp/F was 21.93 +/- 5.18 L/h; the 24-hour urinary recovery was 69.33 +/- 6.13% and the renal clearance was 12.58 +/- 2.99 L/h. The above pharmacokinetic parameters obtained from the two regimens were compared by two-way ANOVA corrected for the change-over effect. No significant difference was found for Tmax, T1/2 or renal clearance (p > 0.05). Higher AUC, Cmax, urinary recovery and lower Clp/F values were observed for the regimen with food (p < 0.05). The plasma drug concentrations resulting from the regimen with food were higher throughout the 12-hour sampling period when compared to the regimen without food.(ABSTRACT TRUNCATED AT 250 WORDS)


The role of endothelin-1 during ischemia-reperfusion injury.

In order to investigate the role of endothelin-1 during ischemia-reperfusion injury, 80 adult male Wistar rats were subjected to three hours of ischemia and one hour of reperfusion. Animals were evenly divided into eight groups. The rats in group 1 served as the normal control group, while the rats in group 2 received an intravenous infusion of endothelin-1 in a dosage of 0.5 ng/kg/min, group 3 in a dosage of 5 ng/kg/min, and group 4 in a dosage of 50 ng/kg/min. The rats in group 5 were infused with angiotensin II (10 ng/kg/min). The rats in group 6 received an intravenous infusion of 10,000 units of superoxide dismutase and 10,000 units of catalase. Group 7 rats were infused with endothelin-1 (50 ng/kg/min), superoxide dismutase (10,000 units), and catalase (10,000 units). Group 8 rats received an infusion of angiotensin II (10 ng/kg/min), superoxide dismutase (10,000 units) and catalase (10,000 units). The infusions were given during the reperfusion period. After one hour of reperfusion, the gastrocnemius and soleus muscles of the experimental animals were excised and assayed for ischemia-reperfusion injury by measuring triphenyltetrazolium chloride (TTC) reduction. The results showed that the limb activity of the ischemic extremity was 40.33 +/- 2.75% in group 1, 41.62 +/- 4.08% in group 2, 14.42 +/- 3.14% in group 3, 4.43 +/- 1.05% in group 4, 23.81 +/- 3.51% in group 5, 57.23 +/- 4.52% in group 6, 31.79 42- 3.63% in group 7, and 27.39 +/- 3.95% in group 8. Endothelin-1 reduced the limb activity in a dose-dependent manner.(ABSTRACT TRUNCATED AT 250 WORDS)


Cerebrotendinous xanthomatosis in three siblings from a Taiwanese family.

We present and discuss the clinical and biochemical findings of three siblings with cerebrotendinous xanthomatosis, which has not been previously reported in Taiwan. Clinical features consisted of tendinous xanthomas, cataracts, mental defects, pyramidal signs, cerebellar ataxia, peripheral neuropathy and renal stones. Biochemical findings included normal serum cholesterol levels, high serum cholestanol levels and elevated serum cholestanol to cholesterol ratios. The serum levels of cholesterol precursor (lathosterol) and plant sterols (campesterol, sitosterol) were also elevated.


Hypothalamic amenorrhea in a case of mitochondrial encephalomyopathy.

A 26-year-old female with myoclonus epilepsy associated with ragged-red fibers is reported. Clinically, she had myoclonus epilepsy, cerebellar ataxia, a bilateral neurosensory type hearing loss, retinitis pigmentosa and short stature. She also presented with primary amenorrhea and poor development of secondary sexual characteristics. Endocrinologic studies revealed that hypothalamic dysfunction was the most plausible cause of her primary amenorrhea. Magnetic resonance imaging showed marked dilatation of the third ventricle indicating thalamic and hypothalamic degeneration. We conclude that hypothalamic dysfunction may be one of the characteristic features of mitochondrial encephalomyopathies.


Extrathoracic sarcoidosis in a Chinese man presenting with multiple, large plaques and tumors.

We report an unusual case of tumorous sarcoidosis in a 42-year-old Chinese man with extrathoracic sarcoidosis. He presented with multiple large plaques and tumors on the neck and extremities of a nine-year duration. Because of the atypicality of the cutaneous manifestation, the lack of intrathoracic lesions and the rarity of sarcoidosis in Taiwan, the case remained undiagnosed for nine years despite numerous examinations and tests. A subsequent skin biopsy revealed sarcoidal granulomas. The detection of cytoplasmic birefringent inclusions in the granulomas led to the final diagnosis. Originally thought to be foreign bodies, the inclusions were proven to be calcium oxalate by x-ray microanalysis and calcium oxalate stain. Lymph node and liver biopsies confirmed the diagnosis. The skin lesions in this case may have been precipitated by frequent harsh scrubbing to clean the skin. Sarcoidosis should be considered in the differential diagnosis in patients presenting with multiple cutaneous tumors. This case also illustrates that detection of calcium oxalate inclusions in granulomas, while not specific, can serve as a valuable clue in the diagnosis of cutaneous sarcoidosis.


Magnetic resonance imaging of Ebstein's anomaly: report of two cases.

Among 388 cases of congenital heart disease with magnetic resonance imaging (MRI) from September 1990 to February 1992, we came across two cases of Ebstein's anomaly. They had been previously diagnosed as Ebstein's anomaly by echocardiography and cinecardioangiography. The first case was a three-year-old boy with complex congenital heart disease that included Ebstein's anomaly, a double-outlet right ventricle, pulmonary hypertension, tricuspid regurgitation, mitral regurgitation, a ventricular septal defect and an atrial septal defect. The second was a 13-year-old boy who also had Ebstein's anomaly, but had received a tricuspid valve replacement at the age of five. In Ebstein's anomaly, we found that MRI offers exquisite endocardial and epicardial details. We anticipate that in the future MRI will help to eliminate invasive studies.


Monitoring of serum neopterin in renal transplant recipients.

Postoperative management of kidney allograft recipients requires a reliable and rapid diagnostic method so that proper therapy can be initiated. In this study, we tried to correlate serum neopterin levels with different conditions after transplantation. Serial serum neopterin levels were assessed after operation. Serum neopterin levels of uremic patients were significantly higher than those of healthy persons (239.9 +/- 177.7 nmole/L, n = 33 vs 6.14 +/- 2.78 nmole/L, n = 10, p < 0.001). In recipients with a stable post-transplant course, the serum neopterin level was low. On the contrary, acute rejection episodes were associated with a high level of serum neopterin which declined after successful treatment, although the difference was not significant (96.2 +/- 57.7 nmole/L vs 56 +/- 38.1 nmole/L, p > 0.05). The serum neopterin level was also high in post-transplant acute tubular necrosis (ATN, 256.6 nmole/L), which gradually declined parallel to the resolution of ATN. The neopterin level was low in patients with cyclosporine nephrotoxicity (17.8 +/- 7.6 nmole/L). In summary, the serum neopterin levels were persistently high in uremic and post-transplant ATN patients. Acute rejection episodes were correlated with an increased level of neopterin. It appears that daily measurement of the serum neopterin level may be useful for biochemical detection of immunologic complications in allograft recipients.


Neonatal screening for alpha-thalassemia in southern Taiwan.

Screening peripheral or cord blood from newborn infants has been used for early detection of alpha-thalassemia conditions. The level of hemoglobin Bart's (Hb Bart's) in the blood correlates with the degree of alpha-gene deletion. Hence, the degree of gene deletion in an alpha-thalassemia carrier state can be estimated. Two thousand cord blood samples collected from the Tainan area were screened with cellulose acetate membrane electrophoresis for Hb Bart's. Ninety-nine of the 2,000 samples (4.95%) were positive for Hb Bart's. Concentrations of Hb Bart's varied from 3.2% to 30.7%. Of the 99 cases with Hb Bart's, 22 had Hb Bart's levels of 3.0% to 9.9%; 54 had Hb Bart's levels of 10.0% to 19.9%; and 23 had Hb Bart's levels of 20% to 40%. Routine cord blood screening by hemoglobin electrophoresis is recommended.


Hemiparkinsonism in a patient with frontal meningioma.

We report on a 44-year-old woman with a right frontal meningioma, who presented with resting tremor, rigidity and bradykinesia in the left limbs. There were no other neurologic manifestations. A computed tomography scan demonstrated a huge high-density mass in the right frontal lobe and marked surrounding edema causing compression of the basal ganglia. Cerebral angiography showed a typical sunburst tumor stain and three feeding vessels from the bilateral middle meningeal arteries and the right callosomarginal artery. The pathologic diagnosis was transitional type meningioma. Before surgery, treatment with levodopa and bromocriptine was significantly effective in controlling hemiparkinsonism, which completely disappeared after surgical removal of the tumor. This outcome supports the notion that local compression due to edema may cause a functional disorder in the basal ganglia producing reversible contralateral parkinsonism.


Clonal analysis of agnogenic myeloid metaplasia.

Agnogenic myeloid metaplasia (AMM) is a chronic myeloproliferative disorder that leads to a sustained proliferation of megakaryocytes and an increase of reticulin fibers within the bone marrow. Blood and bone marrow samples from patients with advanced AMM with fully developed myelofibrosis as well as cases in the cellular phase of the disease were investigated for clonality. Clonality was studied by X-linked restriction length polymorphism in conjunction with DNA methylation patterns. Granulocytes and total bone marrow cells proved to be monoclonal in origin whereas at least a minor portion of the peripheral lymphocytes were not clonally derived. Our findings indicate that the cellular phase of AMM as well as the fully developed disease progressed to myelofibrosis represent a monoclonal proliferation of pluripotent hematopoietic stem cells.


Recent developments in medical therapy of POAG with beta blocking agents.

Since 1987, an entirely computerized open study has been developed in Pr Sole's Ophthalmology Department: the CLERTORE project (Clermont-Tonus-Research). It is a data bank including all the ophthalmic data of hypertensive patients, whether treated or untreated. Every six months, the patients included in the CLERTORE project undergo a clinical ophthalmic examination as well as an automated visual field examination (OCTOPUS 500), an examination of the optic disc (ONHA) and fluorophotometry (FLUOROTRON MASTER). To date, 92 patients have been included in the project. One hundred and eighty-three eyes are examined every six months with a maximal follow-up of 42 months. Because of the numerous criteria of the data base, it is too early to give any statistical results. With a close look at the evolution of the examinations of some of our cases, this preliminary work however allows us to make the three following remarks: In the hypertensive patients, a modification of the papillary pallor is observed without any change in the visual field, C/D ratio and fluorophotometry. The pallor is clearly modified when adrenaline eye drops are given to glaucomatous patients. There is a break of the iridic blood barrier in some hypertensive patients, whether treated or untreated.


[Immunocytochemical research on mediators of centrifugal visual neurons in lampreys (Lampetra fluviatilis)].

The aim of this study has been to investigate different neuroactive substances in the lamprey centrifugal visual neurons (CVN) by combining axonal tracing methods and immunocytochemistry. The CVN somata are immunonegative to antibodies recognizing FMRF-amide, LH-RH, 5 HT and TH, but immunopositive to an anti-GABA antiserum (GABA+) in a proportion of 40%. In the retina, the GABA+ axon terminals mainly synapse upon GABA+ and GABA- amacrine cell bodies and dendrites, and on dendrites of GABA- ganglion cells.


[The central neurophysiological and neurochemical mechanisms of vomiting (a review of the literature)].

The review contains the present-day evidence on neurophysiological and neurochemical mechanisms of functioning the central components of vomiting reflex. The main attention is concentrated on the role of some brain structures in motion sickness-induced vomiting. At the same time, the literature data casting doubt on traditional view of a necessary involvement of some brain structures in the genesis of vomiting induced by motion sickness are discussed. Also there are findings of studying an effect of physiologically active substances (classical neuromediators and regulatory peptides) at a neuronal level (silent postremal cells) with the presence of an emetic effect in them during systemic administration. The current concept of vomiting center to which role the parvicellular reticular formation of brain stem can pretend is under study.


Comparative cardiac haemodynamics of bisoprolol, celiprolol, carvedilol and nebivolol in normal volunteers.

Nebivolol is a novel selective beta 1-adrenergic antagonist with an unusual haemodynamic profile. It improves left ventricular function in normals and in patients with a damaged left ventricle. We compared the cardiac effects of a 14-day treatment period with 10 mg o.d. of bisoprolol, 400 mg o.d. of celiprolol, 25 mg o.d. of carvedilol and 5 mg o.d. of nebivolol in a placebo-controlled crossover study in 7 volunteers with a mean age of 39 (range 30-53) years. Cardiac haemodynamics were assessed serially by means of systolic time intervals. The ratio of the preejection period to the left ventricular ejection time (PEP/LVET) was used as a indirect measure of left ventricular performance. The results show that the PEP/LVET is a very sensitive and reproducible index of left ventricular function. During treatment with placebo and bisoprolol no changes occurred; during treatment with celiprolol and carvedilol a significant but transient decrease of PEP/LVET occurred, and only during treatment with nebivolol a long-lasting and significant decrease of PEP/LVET occurred. With bisoprolol an increase of PEP and QS2c (total electromechanical systole) was observed, indicative of a negative inotropic effect. In conclusion, nebivolol, in contrast with both classical and vasodilating beta-blocking agents, substantially improves left ventricular function, possibly due to an improvement of diastolic function and left ventricular compliance, which may be of therapeutical value in the treatment of congestive heart failure.


[Sleep induction].

Physiological sleep induction is a fragile phenomenon which may be altered by environmental factors and various somatic and psychiatric disorders. Therefore sleep induction disorder is a common component of different types of insomnia, including sleep-onset insomnia and to a lesser degree multiple awakenings insomnia and early morning awakening insomnia. The treatment of sleep induction disorders is difficult and requires a precise analysis of the disorder and its aetiological factors. Specific treatment of aetiological factors is more likely to be efficacious in the long term than pharmacological sleep induction (eg: psychiatric disorders, sleep apnea syndrome, restless leg syndrome, periodic movements in sleep, disorders of the sleep-wake schedule...) when the use of hypnotic drugs is necessary agents not altering sleep architecture are preferred. Non-pharmacological methods could be used to induce sleep because they provide a better long term efficacy: sleep hygiene, relaxation techniques, biofeedback technique, psychotherapeutic techniques. Recently, some authors stress the use of treatment by restriction of time in bed and stimulus control treatment.


Targets of homeotic gene regulation in Drosophila.

We have used a chromatin immunopurification approach to identify target genes regulated by the homeotic gene Ultrabithorax. A monoclonal antibody against the Ultrabithorax gene product is used to immunopurify in vivo Ultrabithorax protein binding sites in embryonic chromatin. The procedure gives an enrichment of sequences with matches to a consensus homeodomain binding site. In one case we have shown that an immunopurified sequence lies within a 4 kb fragment that acts in vivo as a homeotic response element. We anticipate that this approach will enable us to identify further targets, allowing the analysis of their regulation and function. The chromatin immunopurification strategy may be of general application for the identification of direct in vivo targets of DNA-binding proteins.


Pax genes, mutants and molecular function.

The paired domain is a conserved DNA binding motif which was first found in Drosophila segmentation gene products. This paired domain is encoded by a well conserved, paired box DNA sequence, also detected in the genomes of other species. The mouse paired box-containing genes are referred to as Pax genes and are expressed in a distinct spatiotemporal pattern during embryogenesis. Pax proteins are able to bind to specific DNA sequences and modulate transcriptional activity. Interestingly, three different Pax genes have already been shown to correspond to some mouse and human mutants, emphasizing their role as developmental control genes.


Pharmacological properties and mechanism of action of the cyclopyrrolones.

We present the pharmacological properties of two cyclopyrrolones, zopiclone as a hypnotic and suriclone as an anxiolytic, and examine their mechanism of action. The effects of zopiclone on the amount of time spent at each vigilance level have been studied in freely moving rats. Zopiclone from 2.5 mg/kg i.p. extends the duration of slow wave sleep (SWS), concomitantly shortening the periods awake. This SWS inducing effect of zopiclone was more potent after 10 mg/kg i.p.; moreover, zopiclone did not depress REM sleep and no rebound of activity in wakefulness or REM sleep were observed the day after zopiclone treatment. In rats, at the cortical level, zopiclone increases the spectral energy in the delta band (0.5 to 4 hertz). This rise in energy appears at doses starting from 1.25 mg/kg p.o. and can also reach the fast frequencies (beta band: 12 to 16 hertz). This power spectrum is characteristic of a compound having tranquilizing-hypnotic potential. Taken together these EEG results corroborate the clinical studies. In man, zopiclone increased SWS, decreased SWS latency and respected sleep architecture in both healthy volunteers and insomniacs. This respect of sleep structure and the relative short duration of action of zopiclone minimized the residual effects seen upon waking (drowsiness, impairment of psychomotor performance). In the Geller-Seifter test, an operant conflict procedure, the minimal effective dose (MED) of suriclone in reversing the conflict-induced inhibition of drinking behavior was 2.5 mg.kg-1 p.o. in rats. Depression of unpunished responding is only seen at higher doses (20 mg.kg-1 p.o.).(ABSTRACT TRUNCATED AT 250 WORDS)


[Contribution of zolpidem in the management of sleep disorders].

Zolpidem is a nonbenzodiazepine hypnotic agent belonging to a new class of psychotropic drugs the imidazopyridines which enhance the GABAA receptor function by interacting with a specific receptor population. Zolpidem binds selectively to the Omega-1 receptor subtype and from a pharmacological point of view differs from benzodiazepines (BZD) by producing a strong sedative and hypnotic profile which predominates over the anticonvulsivant and anxiolytic activity and moreover appears practically devoid of myorelaxant properties. From a pharmacodynamic point of view, these results suggest that zolpidem facilitates more selectively than BZD, GABAA function and produces a selective hypnotic effect. Though if the role played by receptors in tolerance and dependence has not been yet fully elucidated, it could be described as an adaptative process to sustained stimulation of GABA function. Animal data obtained with zolpidem differs substantially from that of the BZD and indicates that repeated zolpidem administration may not lead to phenomena of tolerance and withdrawal syndrome after abrupt drug discontinuation. In human following oral intake, zolpidem is very rapidly (Tmax: 30-40 min) absorbed. The clearance is essentially metabolic and less than 1% is recovered in urine. The apparent plasma half-life is of 2.0-2.5 hours in most adult subjects and metabolites are totally inactive. The hypnotic activity of zolpidem and its effects on sleep architecture have been assessed in polysomnographic studies: 11 studies in 579 healthy volunteers and 12 studies in 202 insomniac patients. From all the patient studies, it emerges clearly that zolpidem at the dose of 10 mg significantly decreases sleep onset latency, the number and the duration of nocturnal awakenings, and concomitantly increases total sleep time. Furthermore, at variance with what observed with reference benzodiazepine hypnotics, zolpidem does not alter patient sleep architecture: it increases only moderately stage 2, it increases, when reduced, stages 3 and 4 (slow wave sleep) and it does not decrease REM sleep. Clinical studies conducted on more than 4,000 insomniac patients have clearly shown that at the dose of 10-20 mg, zolpidem induces from the first night a definite hypnotic effect in all types of insomnia. In elderly subjects an initial dose of 5 mg should be considered. The possible presence of residual effects during the day following administration of zolpidem has been assessed in 535 healthy volunteers and in 133 insomniac patients according to a double blind (versus placebo and/or benzodiazepine) controlled design.(ABSTRACT TRUNCATED AT 400 WORDS)


[Chronic prostatodynia and psychosomatic care].

Depression is a regular accompaniment of all chronic painful conditions. A study was conducted to assess the effect of treatment of the depressive factor in patients with chronic prostatodynia. Effects were compared of psychosomatic therapy (psychotherapy, relaxation, etc.) alone in 9 patients (group I) and the same psychosomatic care plus treatment with amineptine and clobazam in 9 patients (group II). Results showed that 2 patients recovered and 3 were improved (62%) with 1 drop-out in group II, versus recovery and 2 improvements (42%) with 2 drop outs in group I. These findings are analyzed and discussed.


[Neurotransmitters, neuropeptides and eating behavior].

A number of monoamines and neuropeptides are involved in the control of eating behavior. In the central nervous system, the medial and lateral hypothalamus (connected with cortical and limbic systems as well as with the peripheral endocrine and autonomic nervous systems) integrates informations concerning the nutritional and biopsychological status and control feeding behavior and weight regulation. Modern neurobiological techniques have generated a great range of information on the role of monoamines and neuropeptides in controlling food intake. Substances such as norepinephrine, opioids, neuropeptide Y are potent stimulators of investive behavior. Serotonin, cholecystokinin, and corticotropin-releasing factor inhibit food intake. The physiological influence of these substances is undergoing evaluation.


Morphogenetic roles of retinoic acid.

We integrated our information on morphogenetic roles of retinoic acid, focusing on development of chick limb. Retinoic acid has been considered to be a putative morphogen released from the ZPA. However, since exogenous retinoic acid induces expression of RAR beta, but not grafted ZPA, the ZPA is unlikely to produce retinoic acid. From the result that retinoic acid-treated cells induce digit duplication, retinoic acid converts anterior cells into ZPA cells. We found that retinoic acid also induces expression of homeobox genes indirectly and that bFGF enhances expression of the homeobox genes. Thus, we considered that retinoic acid and growth factors cooperate with each other to activate homeobox genes. A morphogenetic role of retinoic acid is to coordinate developmental stage of each cells by controlling expression of homeobox genes.


Neurotransmitter releasing action of 6R-tetrahydrobiopterin.

We showed that 6R-BH4, a natural cofactor for aromatic amino acids hydroxylases, can stimulate exocytotic DA release independently of its cofactor activity, and ACh release via monoaminergic system. From these results, it is quite likely that 6R-BH4 plays an important role in the regulation of neuronal activity, as a modulator of neurotransmitter release as well as a cofactor for hydroxylases.


Effects of stimulation of the dorsal motor nucleus of the vagus on the extrahepatic biliary system in dogs.

This study was performed to determine the distribution of excitatory and inhibitory areas in the dorsal motor nucleus of the vagus (DMV) for the gallbladder and sphincter of Oddi in spinal cord-transected dogs. Microinjection of 0.5 M L-glutamate into the DMV induced various effects on the gallbladder and sphincter of Oddi. Stimulation at the rostral portion of the DMV elicited only excitatory effects on both motilities. Stimulation at the middle portion of the DMV induced excitatory, inhibitory, or combined effects on the gallbladder and excitatory or combined effects on the sphincter of Oddi. Stimulation at the caudal portion of the DMV elicited the three different effects on the sphincter, but only relaxation of the gallbladder. The locations of the excitatory and inhibitory points for the gallbladder and sphincter were mixed in the DMV at the levels near the obex. From these results, it was concluded that the inhibitory points for the gallbladder and sphincter of Oddi are distributed in the caudal portion of the DMV, while their excitatory points are distributed over a wide area and in the more rostral portion of the DMV.


The actions of baclofen on neurones and synaptic transmission in the nucleus tractus solitarii of the rat in vitro.

1. Intracellular and whole-cell patch recordings were made from sixty-seven neurones located in the nucleus tractus solitarii (NTS) in transverse slices of rat brainstem. 2. Baclofen at concentrations of 2-20 microM caused hyperpolarization from normal resting membrane potentials (Vm). This response was associated with a decrease in input resistance (Rm) tested by current pulses in discontinuous current clamp mode when membrane potential was restored to control level by current injection. In single electrode discontinuous voltage clamp mode, baclofen at these concentrations caused a small (< 50 pA) outward current associated with increased membrane conductance measured by voltage steps from holding potentials (Vh) of -50 or -60 mV. Current-voltage relations at these Vhs and the results of varying Vh between -50 and -110 mV during responses to baclofen gave a reversal potential of -73 mV. The amplitudes of baclofen responses were related to K+ concentration tested by comparing responses in media containing 1-24 mM extracellular K+, indicating that postsynaptically baclofen acts via a K+ conductance. 3. These effects were still apparent in the presence of tetrodotoxin (which did not abolish all spontaneous synaptic activity) and also in medium containing a combination of Co2+, the excitatory amino acid antagonist 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX) and the GABAA antagonist bicuculline which blocked synaptic activity. 4. The amplitude and frequency of spontaneous postsynaptic potentials (spPSPs) and spontaneous postsynaptic currents (spPSCs) were reduced by baclofen at concentrations (1 microM or less) which had no effect on membrane potential or holding current in current or voltage clamp recordings respectively. 5. The amplitude of evoked excitatory (evEPSPs/evEPSCs) and inhibitory (evIPSPs/evIPSCs) synaptic events elicited by electrical stimulation in the vicinity of the tractus solitarius (TS) was reduced by low concentrations of baclofen (250 nM-1 microM) which did not produce discernible postsynaptic responses. 6. In order to examine the effects of baclofen on excitatory synaptic events without contamination with inhibitory events, stimulation of the TS was carried out in the presence of bicuculline. Conversely to investigate actions on purely inhibitory synaptic responses experiments were carried out with CNQX in the bathing solution. Inhibitory synaptic responses could still be evoked, presumably by stimulation of interneurones in the vicinity of the TS. IPSPs/IPSCs were more sensitive to baclofen than EPSPs/EPSCs. 7. The effects of baclofen on membrane potential or holding current and PSP/PSCs were antagonized by 2-hydroxysaclofen (400 microM) confirming that baclofen was acting at gamma-aminobutyric acid (GABA)B receptors.(ABSTRACT TRUNCATED AT 400 WORDS)


Neuronal changes in the nigrostriatal pathway of 1-methyl-4-phenylpyridine-treated mice.

Thirty young-adult mice were treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) 30 mg/kg/day for 2 days and sacrificed 24 hours later in order to determine striatal catecholamines and to study morphological changes in the nigrostriatal pathway. Immunohistological techniques were also used with polyclonal antibodies for glial fibrillary acidic protein (GFAP) and tyrosine hydroxylase (TH), and monoclonal antibodies for two subunits of neurofilaments. Silver impregnation demonstrated conspicuous neuronal changes affecting cellular processes from substantia nigra in all treated mice. Terminal and axonal degeneration were also observed in striata. These changes were associated with a moderate to marked gliosis. The TH immunoreactivity was normal in cell bodies of substantia nigra but was decreased in striata from MPTP-treated mice. These data indicate that in mice the deterioration of dendritic and axonal neuropil may constitute a significant causal factor of MPTP neurotoxicity.


Analysis of the regions responsible for IS6110 RFLP in a single Mycobacterium tuberculosis strain.

A high degree of IS6110 restriction fragment length polymorphism (RFLP) is observed amongst the different strains of the Mycobacterium tuberculosis complex. The sequences of the IS6110 flanking regions from a M. tuberculosis strain harbouring four IS6110 copies were determined. Duplication of 3-4 nucleotides was found at the extremities of the four IS6110 copies, suggesting that IS6110 RFLP is due to transposition of the IS element. One of the copies of IS6110 analysed in the study was shown to be located at the same site in the genome of M. tuberculosis as the single copy present in an M. bovis BCG strain.


The success of histamine-2 receptor antagonists.

The lives of both patients and doctors have been revolutionized since the development of histamine-2 receptor antagonists. Their development has introduced, for the first time, a rapid, reliable, and save means of healing both duodenal and gastric ulceration. The continuous administration of these agents has additionally been shown to reduce ulcer relapse and subsequent complications. In addition, they offer some protection from the development of nonsteroidal anti-inflammatory drug-induced damage. The symptomatic relief of reflux together with healing of oesophagitis has been of further benefit. The drugs in this group have become one of the most widely used ethical pharmaceuticals in the world, with ranitidine (Zantac) as the biggest-selling drug in the world for the last few years. Their success can be attributed to their simplicity of use, safety, and above all, their efficacy. Their current role in gastroenterologic practice, in the face of new developments such as Helicobacter eradication and the development of proton pump inhibitors, will be discussed.


[Neuroleptic malignant syndrome and related conditions].

Neuroleptic malignant syndrome is characterised by muscular rigidity, fever and signs of severe vegetative nervous system involvement. Its etiopathogenesis is still unclear and the disease is potentially fatal. Its clinical aspects, which are often only partially manifested, make it difficult to formulate a correct diagnosis in time, not least due to the problem of differential diagnosis with other syndromes with similar symptoms but a different pathogenesis, psychopathology and therapy: acute lethal catatonia, fatal acute delirium, heat-stroke, malignant hyperthermia. The speed of the diagnosis is vital for effective therapy, but this is made even more difficult by the need approach. The paper presents eleven case studies; after an analysis of the numerous clinical aspects of the syndrome and the definition of its diagnostic parameters, an appropriate therapeutic protocol is outlined. Lastly, the problem of retreatment using a neuroleptic of the same or a different class is discussed once the acute phase has been overcome.


[Takayasu disease. Diagnostic criteria and therapeutic procedure].

A study of 11 cases of Takayasu's disease, collected from the cardio-vascular surgical service of Sfax, has been realized during the 4 year-period from 1988 to 1991. Womanly predominance was neat. The average age was 40 years, with extremes of 24 and 56 years. Dominant revealing symptoms was upper limb ischaemia found in 9 cases, a reno-vascular hypertension rebelled to medical treatment was noted in 2 cases. Arteriography have showed a preferential localization of lesions in the subclavian artery essentially at the post-vertebral segment. Lesions types were dominated by stenosis and obliteration, then aneurysms were rare. Operative indication was posed in 9 cases. 11 revascularisations procedures were performed of which 10 arterial by passes and one resection graft. Two bypasses were obstructed, the 9 remaining bypasses have a good previous checked clinically and by angiography (or echo-doppler) with a mean follow-up of 14 months.


[Anaphylactic shock complicated by myocardial infarction: side effect of glaphenine?].

The authors report a case of anaphylactic shock complicated by coronary spasm and infarction attributed to glafenine medication in a 43-year-old male patient. The outcome was positive and coronary angiography showed healthy coronary vessels. The ergonovine maleate was negative. A review of the literature confirms the rarity of this complication of anaphylactic shock and study the ECG changes induced by this type of reaction and to analyze the mechanisms responsible for this coronary spasm in this situation. These consists basically of histamine release and prostaglandin-synthesis inhibition.


Overpressured layer chromatographic study of retention behaviour of various benzodiazepine derivatives on layers impregnated with tricaprylmethylammonium chloride.

The retention behaviour of various benzodiazepine derivatives was investigated on silica gel layers impregnated with tricaprylmethylammonium chloride (TCMA). The chromatograms were developed by means of overpressured layer chromatography (OPLC). As for the case of amino- and nitrosalicylic acids, pyrimidine derivatives, barbiturates, penicillins, cephalosporins and tetracyclines, the retention of benzodiazepine derivatives increased with increasing layer TCMA concentration with eluents containing methanol and water, but not TCMA. On increase of the methanol content of the eluent, a retention-decreasing effect was observed. On layers impregnated with TCMA, a linear relationship existed between the RM values of the benzodiazepines and the methanol content of the eluent. A similar relationship held for silica gel layers impregnated with paraffin oil (traditional reversed-phase). There was no correlation between the results obtained on layers treated with TCMA or with paraffin oil. On TCMA-impregnated layers, the retention of compounds having different chemical structures showed no dependence on the pH of the eluent. There were two reasons for this. Firstly, as it was established, above a certain RF value, the pH of the layer in the presence of TCMA was almost identical irrespective of the original pH of the buffer. Secondly, below this RF value, the actual pH of the layer did not have a strong enough effect to cause appreciable differences between the retentions of the dissociated and undissociated species of the analytes. The conditions for optimum separation are given.


[Fetal liver transplantation in mice: tolerance induction by portal venous inoculation with allogeneic cells followed by injection of cyclophosphamide].

BALB/C mice (H-2d) receiving allogeneic C57 mice (H-2b) spleen cells via the portal vein (PV), followed by administration of cyclophosphamide (CY), abrogated the capability of rejecting allogeneic EL-4G- tumor cells (C57 origin). BALB/C mice received this combined treatment and BALB/C mice untreated or treated with either PV presensitization or CY injection were all exposed to 7.5 Gy total body irradiation, which was confirmed to be a lethal dose for BALB/C mice, then given intravenously 2 x 10(7) fetal liver cells from C57 mice (FLC57). The results indicated that the survival times of grafted BALB/C mice combined treatment were longer than those of untreated or either PV or CY treated, (PV + CY + 7.5Gy + FLC 57: MST = 99.5 +/- 12.6 day), v(N + 7.5GY + FLC57: MST = 36.5 +/- 9.8 day; PV + 7.5Gy + FLC57: MST = 12.2 +/- 0.2 day; CY + 7.5Gy + FLC57: MST = 27.6 +/- 5.5 day). The difference was statistically significant. The spleen cells from the grafted mice were assessed by indirect immunofluorescence with anti-C57 serum. The spleen cells from BALB/C mice with survival time over 100 days after grafting of FLC57 in combined treatment group were about 70-80 percentage of C57 positive cells.


Evaluation of six chiral stationary phases in LC for their selectivity towards drug enantiomers.

Six chiral stationary phases (CSP) were evaluated for their enantioselectivity towards a series of 45 drugs with different acidic, basic or neutral properties. These CSPs were: a polyacrylamide phase, Chiraspher; two polysaccharide-based phases, cellulose tris-3,5-dimethyl phenylcarbamate (Chiralcel OD) and the S-naphthylethylcarbamate derivative of beta-cyclodextrin (SN-beta-CD; Cyclobond I SN); and three protein-based CSPs--alpha 1-acid glycoprotein (Chiral-AGP), ovomucoid (OVM) and cellulase. A total of 28 different mobile phases were involved. Chiral-AGP, OVM and Chiralcel OD appeared to be the most promising CSPs for the enantio separation of the series of structurally different compounds evaluated. Cellulase and Chiralcel OD show particularly high enantioselectivity towards the group of beta-blocker drugs. The different protein-based CSPs were used in their usual reversed-phase mode. The other phases were used in combination with apolar mobile phases, except for SN-beta-CD, which was evaluated in both modes. Formal optimization strategies were not adopted, although the effect of organic modifier and eluent pH on enantioselectivity was briefly examined for the protein-based phases.


Analysis of new serotonergic anxiolytics by liquid chromatography.

A simple isocratic procedure was developed for the analysis of new serotonergic anxiolytics and the related compounds in bulk materials, pharmaceutical formulations and in biological samples. The system may be applied for the assay of other serotonergic anxiolytics of related structure such as buspirone. The liquid chromatographic assay utilizes a reversed-phase C18 column, a mobile phase consisting of a mixture (55:45, v/v) of (A) buffer potassium dihydrogen phosphate (0.05 M) containing sodium lauryl sulphate (0.005 M) and (B) acetonitrile. A fluorescence detection is used with lambda ex 237 nm; lambda cm 374 nm. The accuracy, precision and sensitivity of the proposed method are established. Standard curves are linear with respect to concentration in the range 0.05-7.5 micrograms ml-1. The method also allows the separation and identification of related compounds at concentrations below 0.01%.


[The choice of treatment in acute hemorrhagic necrotic pancreatitis: medical or surgical?].

In recent ten years, physicians and surgeons in Beijing Tong Ren Hospital cooperated well in the treatment of acute hemorrhagic necrotic pancreatitis. Twenty four cases were chosen to determine whether medical conservative or surgical operative treatment should be given. In the surgical operation group there were fourteen cases. Twelve cases survived and the remaining two died. In the medical conservative group only one of the ten cases died. The overall mortality of the twenty four cases of acute hemorrhagic pancreatitis was 12.5%. In our study, the indications for operation were as follows: (1) Presence of more than five positive diagnostic criteria. (2) Accompaniment of gall stone. (3) Inability to differentiate with other acute surgical abdominal emergencies such as intestinal obstruction.


Resolution of several racemic 3-hydroxy-1,4-benzodiazepin-2-ones by high-performance liquid chromatography on a chiral silica-bonded stationary phase.

The resolution of four racemic 3-hydroxy-1,4-benzodiazepin-2-ones, widely used in therapeutics, by means of a chiral stationary phase is described. The chiral selector used is (S)-N-(3,5-dinitrobenzoyl)phenylalanine. This chiral stationary phase showed both good enantioselectivity and efficiency for the compounds. Elution times were in all cases shorter than those previously reported for such compounds on different stationary phases. Racemic oxazepam was used to evaluate the loading capacity of the chiral stationary phase.


Traumatic dental injuries in normal and handicapped children in Nairobi, Kenya.

Two thousand, seven hundred and ninety one normal and handicapped children aged 5-15 years were examined for traumatic dental injuries. Twelve percent had traumatised teeth while three percent had soft tissue injuries. More handicapped children (18%) than normal children (11%) had injuries. This study indicates that children need to be educated on preventive measures regarding traumatic dental injuries.


Determination of meprobamate in pharmaceutical dosage forms also containing carbromal by liquid chromatography and indirect photometric detection.

In a pharmaceutical form also containing carbromal, meprobamate could not be quantified selectively by classical methods described in pharmacopoeias due to a significant interference from carbromal. Consequently, reversed-phase HPLC methods have been developed to separate the two active ingredients using indirect photometric detection to visualize and determine meprobamate which has very poor chromophoric properties. Different parameters influencing the sensitivity of the indirect response, such as the nature of the highly absorbing compound added to the mobile phase (the marker) as well as the methanol content and the pH of this phase, have been studied. Two chromatographic systems containing benzoic acid or cinnamic acid as the marker, have been optimized and validated. Good linearity and reproducibility have been obtained with both systems but the cinnamic acid method has the advantage that meprobamate and carbromal can be determined simultaneously at 273 nm.


[Effect of poly-saccharide sulphate on thixotropic properties of whole blood in patients with cerebral thrombosis].

Using Low shear 30 rheometer, we measured the thixotropic parameters of blood from 30 patients suffering from cerebral thrombosis. The result showed that the yield stress (tau 0), non-Newtonian contribution of viscosity (eta s-mu) and viscosity of plasma (eta p) were significantly higher than those in the control group. Those patients were randomly divided into two groups. Each group included 15 patients. The patients in group 1 and group 2 were treated with poly-saccharide sulphate (PSS) and DX40 respectively by intravenous drip for 14 days. The results showed that tau 0, A, (eta s-mu) were significant decreased in group 1 after treatment, but no significantly change in the thixotropic parameters was found in group 2 after treatment. The total curative rate in group 1 was higher than that in group 2. These results suggest that the patients with cerebral thrombosis had evidently increased degree of RBC aggregation. PSS could decrease the aggregation of RBC more significantly than DX40 did. It was probably one of the reasons why the therapeutic effect of PSS on cerebral thrombosis was better than that of DX40.


Histologic case reports of coralline hydroxyapatite grafts placed in human intraosseous lesions: results 6 to 36 months postimplantation.

Four intrabony lesions from four patients were studied. Presurgical measurements included clinical attachment level, degree of recession, probing pocket depth, Plaque Index, Gingival Index, and Sulcular Bleeding Index. These measurements were also taken at 6-month intervals after surgery. Surgery involved exposing the intrabony defects by a papillary preservation technique, planing, and placing blocks of coralline hydroxyapatite. Three biopsy specimens and one block section were removed from the treated lesions at various periods ranging from 6 to 36 months. Clinical and histologic observation provided evidence of osteogenesis around and through the coralline hydroxyapatite.


Adhesins and receptors of Pseudomonas aeruginosa associated with infection of the respiratory tract.

Substantial progress has been made in defining a number of Pseudomonas adhesins which may be involved in the pathogenesis of respiratory infection. As yet, it is unclear which of these adhesins are primarily responsible for initiating infection in CF. The findings that CF epithelial cells have increased numbers of receptors for P. aeruginosa attachment and that CF epithelia are less highly sialylated than normal epithelial cells is consistent with a role for Pseudomonas pili in the initial recognition of asialoganglioside receptors on epithelial cells. In addition, there is ample evidence supporting the presence of several classes of non-pilus adhesins. Adherence properties of P. aeruginosa clearly vary from strain to strain and it appears likely that all potential adhesions are not equally expressed. More importantly, the regulation of the expression of these adhesins is unlikely to be constitutive. Some may be expressed only when triggered by the appropriate environmental conditions as found in vivo. In reviewing the pathogenesis of Pseudomonas infection in the CF lung, several classes of receptors must be considered. Pseudomonas infection is limited to the bronchi in CF. The organisms do not invade the bronchial tissue, but remain in the airways forming a biofilm with associated microcolonies. Thus, it would seem reasonable to expect Pseudomonas receptors within respiratory mucin. However, to date, there is little confirmatory data to support the presence of specific receptors in mucin. Alternatively, it is possible that the failure of bacterial binding to mucin components may contribute to colonization as organisms which are not efficiently cleared by muco-ciliary function may persist in the airways long enough to find or expose cryptic epithelial binding sites. This hypothesis is supported by binding studies which demonstrate decreased Pseudomonas attachment to CF as compared with normal respiratory mucins. Based on the available data, there appears to be a hierarchy of adhesin expression. Multiple ligand-receptor interactions may occur in the respiratory tract and it may be difficult to analyze the effect of secondary adhesins in the presence of what appears to be the dominant ligand, i.e. pilin. Thus, the failure to find the expected sialylated receptor for Pseudomonas attachment may be due to methodologic problems such as studying strains under conditions in which pili are well expressed and affinities for asialylated receptors predominate. This may not be the situation in vivo after the initial contact of the infecting organisms with the epithelial surface. Not only must the organism attach initially, but it must then be able to persist within the lung. Further studies, based on genetically defined mutants should help define which P. aeruginosa gene products and which components of the CF but not the normal epithelium are responsible for this unique but ultimately fatal host/bacterium interaction.


Molecular localization of variable and conserved regions of pspA and identification of additional pspA homologous sequences in Streptococcus pneumoniae.

PspA is anchored to the surface of all pneumococci by the C-terminal end of the molecule. The N-terminal half of PspA is known to be serologically variable and to be able to elicit protective immune responses. Molecular analysis with DNA probes spanning different regions of pspA was carried out to identify homologous sequences among pneumococcal isolates. At high stringency, DNA probes derived from the 3'-half of pspA (encoding the C-terminal half of PspA) hybridized to all of 37 pneumococcal isolates tested, representing 20 capsular serotypes and 12 PspA serotypes. Most strains had two sequences highly homologous to this region of pspA. Using derivatives of strain Rx1, with insertion mutations in pspA, it was possible to identify the functional pspA sequence. At 50% stringency, the 3' pspA probes also detected lytA and additional sequences. lytA encodes autolysin and shares homology with the 3' portion of pspA. A probe derived from the 5'-half of pspA (encoding the N-terminal half of PspA) hybridized with only 75% of strains and generally detected only one of the two sequences recognized by the 3' probes. Thus, the 3'-half of pspA appears to contain more highly conserved sequences than the 5'-half of pspA and shares homology with several additional sequences, suggesting that the pneumococcus might make several proteins that interact with the surface by the same mechanism as PspA.


Purification and characterization of Aeromonas sobria Ae24 pili: a possible new colonization factor.

Pili of Aeromonas sobria Ae24 were purified and characterized. The molecular mass of the pilin was estimated to be about 19 kDa by SDS-PAGE. The Ae24 pili were electrophoretically distinguishable from previously reported Aeromonas hydrophila Ae6 W pili and A. sobria Ae1 pili, although all three had indistinguishable morphology and shared a high degree of homology in the N-terminal amino acid sequences. Strain Ae24 and its purified pili adhered to rabbit intestine and agglutinated human and rabbit erythrocytes. Hemagglutination was inhibited by D-galactose and D-mannose, but not by L-fucose. Organisms pretreated with Fab fraction of the antipilus antibody failed to adhere to the intestine. Organisms did not adhere to intestine pretreated with the purified pili. These findings suggest that the pili are a colonization factor of A. sobria Ae24 for the rabbit intestine, and that the receptor is galactose- and mannose-containing structure.


Pathological status and therapy of HIV-infected hemophiliacs in Japan.

In Japan, 1531 out of 4171 hemophiliacs (36.7%) are human immunodeficiency virus (HIV)-infected, and up to 31 December 1991, 324 (21.2%) of these patients had developed AIDS. The Research Committee estimated the peak of the seroconversion period of hemophiliacs in Japan as January 1983, having presumed that new cases of seroconversion would not arise after heat treated concentrates came into general use in 1985. However, after a long 5 years window period starting in 1985, cases of seroconversion are being reported. The present mean rate of reduction in cluster difference 4 (CD4) counts of HIV infected hemophiliacs has been increasing since 1990. At present (1991), the proportion of HIV infected hemophiliacs below 20 years is believed to be approximately 40%. Concomitantly with the aging of this group, the incidence of AIDS is expected to increase in the future. Although the aforesaid factors are conducive to a rising incidence of AIDS, the rate of increase of AIDS incidence among hemophiliacs in Japan is actually decelerating. This can, hopefully, be attributed to the commencement of widespread use of periodic pentamidine inhalation therapy, or the administration of drugs such as AZT (zidovudine) or ddI (didanosine) to AIDS related complex (ARC) cases, or to asymptomatic carrier (AC) cases with CD4 counts below 350 cells for the prophylactic treatment against developing to AIDS. Oral administration of didanosine at a dosage of 400 mg/day, or didanosine at a dosage of 334 mg to 500 mg/day, has been found effective for the treatment of hemophiliacs with AIDS.(ABSTRACT TRUNCATED AT 250 WORDS)


Molecular heterogeneity of beta-thalassemia in Thailand.

beta-Globin genes in 294 chromosomes of beta-thalassemia homozygotes and patients of beta-thalassemia/HbE in the northeast, the middle and the south of Thailand were analyzed by the PCR related techniques: dot blot hybridization, direct restriction assay, direct cloning and direct sequencing of the amplified DNA fragments. Twelve different mutations were detected at various frequencies. They are an A-G at-28, codon 19 (AAC-AGC), a G-T at IVS-1 nt1,a G-C at IVS-1 nt5, a C-T at IVS-2 nt654, a G addition in codons 8/9, a C deletion in codon 41, a 4 bp deletion in codons 41/42, an A addition in codons 71/72, an AAG-TAG in codon 17, a CAG-TAG in codon 26, a TAC-TAA in codon 35 and a 8 bp deletion in codons 123-125. We also developed allele specific-polymerase chain reaction to facilitate non-radioactive detection of the mutation. Origins and spread of mutations are speculated based on the results of determination of haplotypes and frameworks that are linked to the thalassemia alleles.


Function and modulation of the antennal heart of Periplaneta americana (L.).

The antennal heart of Periplaneta americana, a small accessory circulatory pump in the head, shows a rhythmicity with myogenic automatism. The muscle fibres extending throughout of the dilator muscle are electrically coupled. Among the peptides, proctolin causes a dose-dependent strong excitation, but allatostatin does not affect heart rhythm. However, allatostatin applied before proctolin antagonized the proctolin effect. In contrast to this, an immediate heart block produced by octopamine is similar to that produced by electrical stimulation of the nervus cardioantennalis. This inhibition is caused by a K(+)-dependent hyperpolarization. The second effect of octopamine is a delayed increase of the cAMP level. Because octopamine is present at the antennal heart, a physiological role is assumed.


Achatin-I, an excitatory neurotransmitter having a D-phenylalanine residue of Achatina giant neurones.

The neuroexcitatory peptide isolated from Achatina ganglia was identical to the synthetic Gly-D-Phe-L-Ala-L-Asp with respect to either the bioassay experiments using the Achatina neurones or the instrumental analysis (1H-NMR, SIMS, CD and HPLC). We termed it achatin-I (yield: 50 micrograms from 30,000 animals). Its stereoisomer, Gly-L-Phe-L-Ala-L-Asp, termed achatin-II, was also isolated from the ganglia (yield: 17 micrograms), but this was ineffective on the Achatina neurones. Of the eight possible stereoisomers, only achatin-I markedly showed excitatory effects on the two Achatina neurones, PON and TAN, and [D-Ala3] achatin-I (Gly-D-Phe-D-Ala-L-Asp) had the slight effects. Among the fourteen neurones tested, seven, including the two mentioned above, were excited by achatin-I, whereas no neurone was inhibited. Achatin-I produced an inward current (Iin) with an increase in the membrane conductance (g) under voltage clamp. ED50 of achatin-I for exciting the neurones were 0.20-1.47 x 10(-5) M, and its Emax were 6.33-5.02 nA. Of the achatin-I analogues examined, only the three, Gly-Gly-D-Phe-L-Ala-L-Asp, D-Phe-L-Ala-L-Asp and Gly-D-Phe-L-Ala-L-Asn, produced Iin, but much smaller than that of achatin-I. The equiactive molar ratios (EMRs) of the four effective related peptides (three analogues and a stereoisomer) vs. achatin-I were: 8-60 for Gly-Gly-D-Phe-L-Ala-L-Asp, 200 - > 250 for D-Phe-L-Ala-L-Asp and > 200 for Gly-D-Phe-L-Ala-L-Asn and Gly-D-Phe-D-Ala-L-Asp. The Iin induced by achatin-I was blocked under the /Na+/0-free state, but unaffected under the [Ca2+]-free (replaced with Co2+), [Cl-]0-free or [K+]-enriched (3.0 x) medium, indicating that the Iin is produced by the gNa increase of neuromembrane. We propose that achatin-I having a D-phenylalanine residue is an excitatory neurotransmitter of the Achatina neurones.


Neurotransmitters in the gastropod CNS: comparative immunocytochemistry.

The number, distribution, morphology, and projection areas of immunoreactive neurons labelled with different antisera were analyzed in the gastropod species, Aplysia californica, Lymnaea stagnalis and Helix pomatia, representing different levels of evolutionary development of the central nervous system. Our results show that the number of small-size peptidergic interneurons increases considerably in the cerebral ganglia of Helix, when compared to serotonin-immunoreactive neurons. This phenomenon might be connected to the change from aquatic to terrestrial life, involving also a change in the composition and quality of sensory input, reaching the animal from the surrounding.


Respiratory behaviour in Lymnaea stagnalis: pharmacological and cellular analyses.

Using pharmacological and microelectrode approaches, evidence is presented here to suggest that exogenously applied dopamine can coordinate respiratory behavioural patterns and that its effects are reproduced using transmitter precursor such as L-DOPA. It is possible that dopamine reproduces sensory inputs to the respiratory network. Interactions between different transmitter substances underlie modifications of rhythmic discharges and enkephalins are able to modulate the respiratory rhythm.


Immunoregulation of lymphoproliferation in vitro by monocytes and their subpopulations. II. Phenotypic changes of T cells in cultures activated with antigen and mitogen.

The aim of this study was to analyze phenotypes of T cells activated by mitogen (PWM) and antigen (PPD) in the presence of FcR+ or FcR- monocytes. It was found that CD4+ and CD8+ lymphocytes are preferentially activated in the presence of different monocyte subpopulations. Expression of HLA-DR and CD25 on CD4+ lymphocytes was greater in cultures activated in the presence of FcR-. CD8+ lymphocytes were more efficiently activated (expression of HLA-DR) when FcR+ monocytes were added to culture. In the presence of FcR+ monocytes an increased expression of CD45RA antigen on CD4+ cells was also observed. These data support our previous functional studies which showed that "suppressor" T cells of CD8+ phenotype are activated in the presence of FcR+ monocytes.


hsp80 of Neurospora crassa: cDNA cloning, gene mapping, and studies of mRNA accumulation under stress.

Using mRNA isolated from Neurospora crassa mycelium, grown for 14 h at normal growth temperature of 28 degrees C, and heat shocked for 1 h at 48 degrees C, a cDNA library was prepared in the expression vector lambda gt11. Following immunoscreening of this library with a polyclonal antiserum raised against a 80-kilodalton heat-shock protein (HSP80), cDNA clones containing 1.1- and 1.4-kilobase inserts were selected. Analysis of the partial nucleotide sequence and the deduced amino acid sequence of the cDNA clones revealed a remarkable extent of homology with other eukaryotic stress-90 family proteins; 85% identity of the amino acid sequence with that of yeast HSP90(82) was seen. The C-terminal end of the sequence contained the MEEVD motif, characteristic of eukaryotic stress proteins with a predominantly cytosolic localization. The gene for N. crassa HSP80 was mapped to the right arm of linkage group V, using restriction fragment length polymorphism mapping. Its expression during heat shock and recovery was monitored by probing Northern blots of RNA isolated from mycelium grown under various stress conditions.


Goosecoid and the organizer.

The molecular nature of Spemann's organizer phenomenon has long attracted the attention of embryologists. goosecoid is a homeobox gene with a DNA-binding specificity similar to that of Drosophila bicoid. Xenopus goosecoid is expressed on the dorsal side of the embryo before the dorsal lip is formed. Cells expressing goosecoid are fated to become pharyngeal endoderm, head mesoderm and notochord. Transplantation of goosecoid mRNA to the ventral side of Xenopus embryos by microinjection mimics the properties of Spemann's organizer, leading to the formation of twinned body axes, goosecoid is activated by dorsal inducers and not affected by ventral inducers. In the mouse, goosecoid is expressed in the anterior tip of the primitive streak. The availability of two early markers, goosecoid and Brachyury, opens the way for the comparative analysis of the vertebrate gastrula. The results suggest that the goosecoid homeodomain protein is an integral component of the biochemical pathway leading to Spemman's organizer phenomenon.


Topochemical design of bioactive peptides and peptidomimetics.

For the studies of bioactive peptides, our laboratories have been employed an integrated approach including synthesis, bioassays, and conformational analysis. To obtain highly potent, selective and metabolically stable analogs, peptidomimetics such as peptide backbone modifications (retro-inverso structures), constrained amino acids, and cyclic structures have been incorporated into many bioactive peptide sequences. The conformational studies of the resulting analogs have led to topochemical models for the bioactivities of those peptides. This lecture will be focused on the results of such studies on opioids and somatostatin. We have synthesized numerous opioid analogs with various peptidomimetics based on three classes: enkephalins, dermorphin-deltorphins, and morphiceptins. Many of these analogs exhibit high potency, selectivity, and metabolic stability. Conformational studies of these analogs have enabled us to define the structural characteristics necessary for bioactivities of morphiceptins, dermorphins, enkephalins, and deltorphins. From these results, we can propose conformational models responsible for bioactivities at the mu- and delta-receptors. Our studies of cyclic somatostatin analogs are based on the highly active Merck analog c(-Pro6-Phe7-D-Trp8-Lys9-Thr10-Phe11-) (where the superscripts denote position in native somatostatin). To investigate the topochemical preference of backbone and side chains, unusual amino acids, including beta-methylphenylalanine7 or 11, beta-methyltryptophan8, as well as backbone modifications such as retro-inverso structures have been incorporated. The bioactivity profiles of these peptidomimetic molecules provide much information on the effects of backbone and side chain constraints on bioactivity.


Induction of anteroposterior neural pattern in Xenopus by planar signals.

Neural pattern in vertebrates has been thought to be induced in dorsal ectoderm by 'vertical' signals from underlying, patterned dorsal mesoderm. In the frog Xenopus laevis, it has recently been found that general neural differentiation and some pattern can be induced by 'planar' signals, i.e. those passing through the single plane formed by dorsal mesoderm and ectoderm, without the need for vertical interactions. Results in this paper, using the frog Xenopus laevis, indicate that four position-specific neural markers (the homeobox genes engrailed-2(en-2), XlHbox1 and XlHbox6 and the zinc-finger gene Krox-20) are expressed in planar explants of dorsal mesoderm and ectoderm ('Keller explants'), in the same anteroposterior order as that in intact embryos. These genes are expressed regardless of convergent extension of the neurectoderm, and in the absence of head mesoderm. In addition, en-2 and XlHbox1 are not expressed in ectoderm when mesoderm is absent, but they and XlHbox6 are expressed in naïve, ventral ectoderm which has had only planar contact with dorsal mesoderm. en-2 expression can be induced ectopically, in ectoderm far anterior to the region normally fated to express it, suggesting that a prepattern is not required to determine where it is expressed. Finally, the mesoderm in planar explants expresses en-2 and XlHbox1 in an appropriate regional manner, indicating that A-P pattern in the mesoderm does not require vertical contact with ectoderm. Overall, these results indicate that anteroposterior neural pattern can be induced in ectoderm soley by planar signals from the mesoderm. Models for the induction of anteroposterior neural pattern by planar and vertical signals are discussed.


Xenopus Hox-2 genes are expressed sequentially after the onset of gastrulation and are differentially inducible by retinoic acid.

In this paper, we review experiments to characterise the developmental expression and the responses to all-trans retinoic acid (RA) of six members of the Hox-2 complex of homeobox-containing genes, during the early development of Xenopus laevis. We showed that the six genes are expressed in a spatial sequence which is colinear with their putative 3' to 5' chromosomal sequence and that five of them are also expressed rapidly after the beginning of gastrulation, in a 3' to 5' colinear temporal sequence. The sixth gene (Xhox2.9) has an exceptional spatial and temporal expression pattern. The six genes all respond to RA by showing altered spatiotemporal expression patterns, and are also RA-inducible, the sequence of the magnitudes of their RA responses being colinear with their 3' to 5' chromosomal sequence, and with their spatial and temporal expression sequences. Our data also reveal that there is a pre-existing anteroposterior polarity in the embryo's competence for a response to RA. These results complement and extend previous findings made using murine and avian embryos and mammalian cell lines. They suggest that an endogenous retinoid could contribute to positional information in the early Xenopus embryo.


Restriction fragment length polymorphism at the CALCA locus identified by the probe pEMBL36 in immigrant populations of Australia.

Restriction fragment length polymorphisms detected by the cDNA probe, pEMBL36, at the CALCA locus (calcitonin gene and calcitonin gene related peptide) on TaqI blots were examined in samples from Italian, Greek and Vietnamese migrants to Melbourne, Australia and in a sample of residents from the island of Tasmania, Australia. The frequency of the rarer of the two alleles of this polymorphism, A2 (8.0kb) varied between a low of 6% in Vietnamese to a maximum of 38% in Tasmanians. The frequency range of the A2 allele in European populations, however, was considerably less. Analysis revealed no significant heterogeneity for this polymorphism among either the European or European derived populations, and these combined data exhibited a frequency of 33% for the A2 allele. Though based on a very small Vietnamese sample this study suggests that the A2 allele is less frequent in those of Asian ancestry.


DNA polymorphisms associated with the factor VIII:C gene in the Portuguese population.

We have determined the allele frequencies of seven restriction fragment length polymorphisms within or close to factor VIII:C gene in the Portuguese population. The allele frequency of all studied intra- and extragenic biallelic polymorphisms does not differ significantly from those found in other European or Asian populations. On the contrary, the distribution of the different alleles of the TaqI RFLP at the DXS52 locus revealed similarity only with Algerians. We observed a correspondence between the TaqI and BclI alleles at this locus.


Expression of P-glycoprotein on normal lymphocytes: enhancement of the doxorubicin-sensitivity of concanavalin A-responding mouse spleen cells by P-glycoprotein blockers.

The in vitro proliferative response of mouse spleen cells (SC) to the T-cell mitogen, concanavalin A (ConA), displays a doxorubicin (DOX)-resistant component. This T-cell proliferative response displays a much higher DOX sensitivity in the presence of novel potent inhibitors of P-glycoprotein (Pgp)-mediated multidrug resistance (MDR), the cyclosporin (Cs) derivative, SDZ PSC 833, and the semi-synthetic cyclopeptolide, SDZ 280-446. Another resistance modulator, verapamil, might share this property, but its detection was impaired by the intrinsic toxicity of this calcium channel blocker for T-cell proliferation. A CD8+ cell-depleted SC suspension displayed a higher sensitivity to DOX alone, as well as a different sensitivity profile to SDZ 280-446. The CD8+ cells that are sensitized to DOX by the resistance modulating agents (RMA) might correspond to a formerly described T-cell subpopulation with the MDR phenotype, which seems to be essentially constituted of CD8+ (cytotoxic) T cells. Our results may open the way to a novel form of immunomodulation combining classical antineoplastic agents with Pgp-blocking Cs analogs (even non-immunosuppressive ones), which may be particularly useful when treating acute graft rejection.


[Sulglycotide combined with H2-antagonists in the prevention of duodenal ulcer recurrence. Multicenter study].

The aim of the present study was to evaluate the role of sulglycotide, a molecule with gastroprotective properties, in monotherapy and in association with H2-antagonists in the maintenance treatment of duodenal ulcer. The study was performed using a fully randomized experimental design. Following endoscopic confirmation, 626 patients with healed duodenal ulcer were treated for 6 months with sulglycotide 200 mg tid (293 patients) or sulglycotide + H2-antagonists (333 patients). After 2, 4 and 6 months patients underwent a clinical control whereas an endoscopic control was performed after 6 months. The cumulative percentage of recidivation was 3.6% in the sulglycotide + H2-antagonist treated group, whereas the group treated with sulglycotide alone showed a recidivation rate of 15.4% (p < 0.001). These findings suggest the utility of combined sulglycotide and H2-antagonist treatment in the maintenance therapy for duodenal ulcer.


Structure-activity studies of amsacrine analogs in drug resistant human leukemia cell lines expressing either altered DNA topoisomerase II or P-glycoprotein.

In an attempt to characterize and overcome tumor cell resistance to amsacrine (m-AMSA), we studied the structure-activity relationships for amsacrine and seven of its analogs. Using the human leukemic cell line, CCRF-CEM, and its derivatives that express either P-glycoprotein (Pgp)-associated multidrug resistance (MDR) (CEM/VLB100) or altered topoisomerase II-associated MDR (at-MDR) (CEM/VM-1), we assessed antitumor effects of these drugs in a 48-hr growth inhibition assay. We also measured drug-topoisomerase II interactions in an intact cell assay that permits quantitation of drug-stabilized DNA-topoisomerase II complexes. We found that among the tested compounds, amsacrine has an intermediate effect on cell growth in all three cell lines. The CEM/VM-1 cells were 8.6-fold cross-resistant to m-AMSA, and the cross-resistance to the analogs was from 3.0- to 10.5-fold. In the CEM/VLB100 cells, the resistance pattern was different: several analogs, including amsacrine, showed little or no cross-resistance (0.5- to 2.8-fold), whereas for those compounds with substituents at position 3 on the acridine ring, resistance was relatively higher (9.9- or 16.2-fold). Substituents at this position substantially decrease the lipophilicity of the two compounds examined, probably because they both contain amino groups that would be charged at physiologic pH. Compound 12489, having a 1'-NHSO2C6H4NH2 substituent, was very potent in the three cell lines, showing only a slightly higher IC50 value in the CEM/VM-1 line and a lower IC50 value in the CEM/VLB100 and in the CEM cells.(ABSTRACT TRUNCATED AT 250 WORDS)


Synthesis and biodistribution of the alpha 2-adrenergic receptor antagonist (11C)WY26703. Use as a radioligand for positron emission tomography.

The purpose of these experiments was to label an alpha 2-adrenergic receptor ligand with a positron emitting isotope and then test this radioligand in vivo. No-carrier-added [11C]WY26703 was synthesized by methylation of its desmethyl precursor, WY27050 with [11C]H3I followed by purification with HPLC in 14% yield in a synthesis time of 35 min from EOB. Ki values for unlabeled WY26703, ranged from 0.52-1.55 nM in tissues that express a single alpha 2-adrenergic receptor subtype. Tail vein injections of [11C]WY26703 in mice revealed that the compound was distributed in the brain, heart, lungs, spleen, and kidneys. In the brains of rats treated with atipamezole, an alpha 2-adrenergic receptor antagonist, there was no decrease in [11C] accumulation indicating a lack of observable specific binding of the radioligand. When brain tissue was homogenized and filtered, however, atipamezole decreased [11C] activity by 53%. Therefore, [11C]WY26703 crosses the blood-brain barrier and specifically binds to alpha 2-adrenergic receptors with high affinity. Atipamezole treatment decreased only the area of the locus coeruleus [11C] value of the various regions of the brain. The affinity, however, of [11C]WY26703 does not appear to distinguish alpha 2-receptors from nonspecific binding sites. PET study of [11C]WY26703 in a Rhesus monkey showed that influx of [11C]WY26703 into the brain was high for the first few minutes but radioactivity then declined rapidly and did not retain in a specific brain region. This suggests that [11C]WY26703 may not be a useful ligand for imaging human alpha 2-adrenergic receptors by positron emission tomography.


Glycosylation inhibits the interaction of invertase with the chaperone GroEL.

During refolding and reassociation of chemically denatured non-glycosylated invertase from Saccharomyces cerevisiae, aggregation competes with correct folding, leading to low yields of reactivation (Kern et al. (1992) Protein Sci. 1, 120-131). In the presence of the chaperone GroEL, refolding is completely arrested. This suggests the formation of a stable complex between GroEL and non-native non-glycosylated invertase. Addition of MgATP results in a slow release of active invertase from the chaperone complex. When GroEL/ES and MgATP are present during refolding, the final reactivation yield increases from 14% to 36%. In contrast, refolding of the core-glycosylated and the high-mannose glycosylated forms of invertase is not arrested by GroEL. Only a short lag phase at the beginning of reactivation and a slightly increased reactivation yield (64% to 86% for core-glycosylated and 62% to 76% for external invertase) indicate a weak interaction of the glycosylated forms with the chaperone.