Demonstration of direct glycosylation of nondegradable glucosylceramide analogs in cultured cells

After uptake by various cells (human skin fibroblasts, rat neuroblastoma B 104, human neuroblastoma SHSY5Y, murine cerebellar cells), a radioactive and a fluorescent analog of a nondegradable glucosylceramide with sulfur in the glycosidic link were glycosylated to a cell-specific pattern of glycolipid analogs. These results, for the first time, show that a glucosylceramide analog can be conveyed from the plasma membrane of cultured cells to those Golgi compartments that function in the early glycosylation steps of glycolipids. This observation is further confirmed by the fact that the cationic ionophore monensin, known to impede membrane flow from proximal to distal Golgi cisternae, inhibited the formation of complex ganglioside analogs but not those of lactosylceramide, sialyl lactosylceramide (GM3), and disialyl lactosylceramide (GD3).

Volunteer low-risk outpatient surgery for uninsured patients in San Francisco. The Ambulatory Surgery Access Coalition

OBJECTIVE

To provide uncompensated elective low-risk outpatient surgery for uninsured patients through a coalition of volunteer physicians, nurses, and hospitals.

DESIGN

Description of the process of establishing the Ambulatory Surgery Access Coalition (ASAC), the political and administrative obstacles encountered, and the clinical results of treatment of the first 25 patients in the pilot project.

SETTING

The ASAC includes the Kaiser Foundation Hospital, San Francisco, Calif, the University of California, San Francisco, the San Francisco General Hospital (SFGH), the San Francisco Department of Public Health, the San Francisco Consortium of Community Clinics, the Northern California Chapter of the American College of Surgeons, and the San Francisco Medical Society. A pilot program of uncompensated outpatient surgery was performed at the Kaiser Foundation Hospital.

PATIENTS

Twenty-nine patients were referred to the ASAC between January 1 and November 1, 1994. Twenty-six patients were judged to be candidates for surgery, and 25 patients met the criteria for the ASAC program. One patient was referred to SFGH for treatment because of a perceived increased risk for hospitalization after surgery.

RESULTS

Twenty-one patients underwent herniorrhaphy; three, excision of large inclusion cysts; and one, anal fistulotomy. Seventeen procedures were done under local anesthesia, seven under general anesthesia, and one under spinal anesthesia. None of the patients required hospital admission. No wound infections occurred.

CONCLUSION

The ASAC successfully provided uncompensated low-risk outpatient surgery to 25 low-income uninsured patients in San Francisco. The coalition hopes, first, to include other San Francisco hospitals and surgical specialties, and second, to serve as a model for other communities throughout the country.

Effects of treadmill exercise protocol with constant and ascending grade on levelling-off O2 uptake and VO2 max

In order to investigate the effect of an exercise protocol on the levelling-off O2 uptake and VO2 max values, ten male subjects aged 28 +/- 5 yrs, height 1.8 +/- 0.05 m, body mass 76 +/- 6 kg performed two treadmill exercise protocols: 1) constant grade (CG) of 5%, with increasing running speed starting at 6 km.h-1 and increments of 2 km.h-1 every 3 minutes. 2) ascending grade (AG) starting at 0% and increments of 5% every 3 minutes, with constant running speed of 5 km.h-1. During each protocol oxygen uptake (VO2), pulmonary ventilation (VE), tidal volume (Vt), and breathing rate (BR) as well as blood lactate concentration (La) and heart rate (HR) were measured. In CG a levelling-off phenomenon of VO2 in all cases was observed. Aerobic capacity expressed as VO2 max in CG was 46.2 +/- 6.0 ml.min-1.kg-1. In contrast, VO2 max was 35% higher in AG (62.6 +/- 7.2 ml.min-1.kg-1). The behaviour of VO2 indicates a lower efficiency with increasing work load in AG as compared to CG. Regarding maximum performance it can be concluded that VO2 in CG seems to be limited by a mechanical or neuromuscular constraint on the depth of breathing, which is confirmed by a distinct flattening of Vt. The levelling-off of the VO2 in CG, something which is not observed in AG, can be explained plausibly this way.

Verification of the heart rate threshold

Among the methods for determining anaerobic threshold (AT), the heart rate (HR) method seems to be the simplest. On the other hand, many conflicting results from comparing this method with others have been presented over the last 10 years. Therefore, the aim of this study was to compare the heart rate threshold (HRT) with the lactate turn point (LTP)-"second" break point of dependence of lactate (LA) to power output, ventilatory threshold (VT) and threshold determined by electromyography (EMGAT), all determined by the same exercise test and evaluated by the same computer algorithm. A group of 24 female students [mean age 20.5 (SD 1.6) years, maximal oxygen consumption 48.8 (SD 4.7) ml.kg-1.min-1] performed an incremental exercise test on a cycle ergometer (modified Conconi test) starting with an initial power output (PO) of 40 W with intensity increments of 10 W.min-1 until the subjects were exhausted. The HRT, LTP and EMGAT determination was done by computer-aided break-point regression analysis from dependence of functional measures on PO. The same computer algorithm was used for VT determination from the relationship between ventilation (V) and oxygen uptake (VO2) or carbon dioxide output (VCO2).(ABSTRACT TRUNCATED AT 250 WORDS)

Heart rate deflection related to lactate performance curve and plasma catecholamine response during incremental cycle ergometer exercise

The correlation between the behaviour of the heart rate/work performance (fc/W) curve and blood lactate ([la]b) and plasma adrenaline/noradrenaline concentrations ([A]/[NA]) during incremental cycle ergometer exercise was investigated. A group of 21 male sports students was divided into two groups: group I, with a clear deflection of the fc/W curve; group II, without or with an inverse deflection of the fc/W curve. The aerobic threshold (Thaer) and the lactate turn point (LTP) were defined. Between Thaer and maximal work performance (Wmax) the behaviour of the fc/W curve as well as the behaviour of [la-]b and [A]. [NA] were described mathematically. The fc, systolic blood pressure (BPs), W, [la-]b, [A] and [NA] at rest, Thaer, LTP, Wmax, after 3 and 6 min of recovery (Re3/Re6) were calculated. A significant difference between the two groups could only be detected for fc at LTP, Re3 and Re6 (P < 0.05). No significant correlation could be found between individual fc/W-behaviour and individual time course of [la-]b, [A] and [NA]. However, a significant correlation was visible between [la-]b/W-behaviour and individual catecholamine response. These results and the fact that the different flattening at the top of the fc/W curve was related to diminished stress-dependent myocardial function led us to the conclusion that it is possible that sympathetic drive is not directly involved in mechanisms of regulation between load dependent fc and myocardial function. In addition, individual fc/W behaviour was independent of BPs and Wmax, or individual conditions of energy supply.

Genetic and learning factors as major substrata for age-related psychopathological symptoms: concerning the question of a psychology of age

The various episodes of life significant for outbursts of different psychic disorders may give some facilitations of a better understanding of the underlying basic processes. Two of them are considered in several appearances: genetic predisposition and conditioning processes. A psychology of age may be interpreted in a stronger sense as a collision of these two conditions. Surprisingly, the age at onset of some psychic disorders is relatively early in life. This means that we should make every effort to comprehend vulnerability in terms of biological as well as psychological compounds earlier; it could carry on to surrender the dichotomy of biological and psychological factors and to combine different standpoints in a general view which inaugurates therapeutic and prophylactic consequences, too.

TSH response to TRH and ECT

In 31 female patients diagnosed according to DSM-III-R criteria as suffering from 'functional' psychosis (e.g., major depression, schizophrenia, mania) TRH tests were administered before, during and after a course of electroconvulsive therapy (ECT) to investigate the effects of ECT on HPT (hypothalamic-pituitary-thyroid) axis as well as the predictive value of TSH response to TRH on treatment outcome. In 20 patients all three TRH tests were available; no significant changes in the mean TSH response were found over the course of ECT; however, a change towards blunted TSH response at the end of treatment was observed. The initial TSH response did not predict the treatment outcome.

[Drug screening in an Austrian prison]

In the Austrian prison Graz, a randomized group of 64 prisoners (12.5% out of 512 total) was selected to investigate patterns of drug abuse. From this group. 60 consented to drug-screening in urine. While opiates, cocaine, alcohol and amphetamines screened negative, cannabis (in 8.4%) and benzodiazepines (in 20%) had positive results.

Expression of the complement regulatory protein CD59 on human spermatozoa: characterization and role in gametic interaction

Protectin (CD59) is a complement regulatory protein which blocks the membrane attack complex during complement activation. CD59 was identified on the human sperm surface by means of H19, an IgG1 anti-protectin mouse monoclonal antibody. Using indirect immunofluorescence, flow cytometry and immunoperoxidase, CD59 was found to be present on the whole plasma membrane including the head and tail of fresh ejaculated, capacitated and acrosome-reacted spermatozoa. Immunoperoxidase staining of normal testicular sections indicated that this protein was already present on intraluminal germ cells. Analysis of this sperm protein by gel electrophoresis and immunoblotting revealed that its molecular weight of 20 kDa was comparable to that of CD59 expressed on peripheral blood cells (erythrocytes, lymphocytes) and that it was bound to the membrane through a glycophospholipid tail which could be released after treatment with phosphatidylinositol-specific phospholipase C. Associated to membrane cofactor protein (CD46) and decay accelerating factor (CD55) located in the acrosomal membranes, CD59 may participate to the protection of male gametes against complement-mediated damage as they travel through the female genital tract. Moreover CD59, known as an adhesion molecule involved in lymphocyte rosettes, may also participate in cell to cell adhesion during gametic interaction since H19 inhibited sperm binding and reduced the penetration rate and index during the hamster egg penetration test.

Relationship between heart rate threshold, lactate turn point and myocardial function

We examined the relationship between heart rate threshold (HRT), lactate turn point (LTP) and myocardial function expressed as left ventricular ejection fraction (LVEF) determined by radionuclide ventriculography. Two groups of subjects (G I: N = 8; G II: N = 7) with and without a deflection of heart rate performance curve (HRPC) underwent sitting cycle ergometry. HRT (G I), aerobic threshold (AeT; G I, G II), and LTP (G I, G II) were determined by means of linear regression break point analysis. Also, a break point in LVEF performance curve (LVEFBP) was obtained. Power output at HRT and at LTP was not significantly different between G I and G II (272.5 +/- 38.7 W; 294.3 +/- 20.6 W). Power output at LVEFBP (G I: 182.6 +/- 31.7 W; G II: 211.8 +/- 21.5 W) was not significantly different to power output at LTP (G I: 194.2 +/- 32.7 W; G II: 215.2 +/- 24.4 W) and HRT (G I: 193.0 +/- 38.2 W). Significant differences (p < 0.05) could only be found between G I and G II for heart rate (HR) at LTP (G I: 163.5 +/- 5.8 b.min-1; G II: 154.4 +/- 6.7 b.min-1) and LVEF at the end of the load (LVEFend) (G I: 77.9 +/- 2.9%; G II: 71.3 +/- 7.0%). The drop of LVEF at LVEFBP was significantly related to LTP in all cases. The present data suggest that the noninvasive determination of anaerobic threshold by means of heart rate curve analysis is not always possible due to different response of myocardial function and heart rate to graded cycle ergometer exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Nasal administration of naloxone is as effective as the intravenous route in opiate addicts

Naloxone is used intravenously in opiate addiction in emergency cases, in rapid opiate detoxification, and as a diagnostic tool. This is a study comparing the efficacy of intranasal naloxone to other routes (intravenous/intramuscular) in 17 opiate-dependent patients. The nasal drug administration of naloxone was found to be as effective as the intravenous route. The nasal drug application offers a wide margin of safety for patients and medical staff, especially in emergency situations in regard to infection risks associated with vessel puncture.

Toxicologic and pharmacokinetic analysis of intravitreal injections of foscarnet, either alone or in combination with ganciclovir

PURPOSE

The retinal toxicity of single and repeated intravitreal injections of foscarnet was investigated. In addition, the effects of a combination of foscarnet and ganciclovir were studied, and a pharmacokinetic study to determine the ocular pharmacokinetics of foscarnet after intravitreal injection was carried out.

METHODS

Forty rabbits (both albino and pigmented) were used in this study. The electroretinographic (ERG) a-waves and b-waves and oscillatory potentials (OP) were used as as indicators of retinal toxicity. Potential toxicity was also assessed by ophthalmoscopy and histologic studies (light and electron microscopy).

RESULTS

The a-wave and b-wave were not deteriorated with 2.4 mg foscarnet after single or repeated injections. The OP remained unchanged. There was no ERG change after intravitreal injection of a combination of both drugs. No evidence of retinal toxicity was observed by indirect ophthalmoscopy in any case. Light and electron microscopy on semithin sections of retina failed to demonstrate any adverse effects, and showed normal organization and cytoarchitecture of all the layers of the retina without evidence of cytopathology. The ocular pharmacokinetics of foscarnet determined by noncompartmental analysis showed a 34-hour terminal elimination half-life and an apparent volume of distribution of 1.9 ml.

CONCLUSIONS

Based on these results, high doses of foscarnet were not judged toxic to the rabbit retina, with single or repeated injections. Moreover, concomitant injection of the two drugs did not induce any retinal toxicity. These findings suggest that when systemic treatment is to be stopped in patients with AIDS for toxic side effects, either ganciclovir or foscarnet may be used intravitreally as an alternative. Because a combination of the two drugs has been shown to be synergistic, both ganciclovir and foscarnet might be simultaneously injected into the vitreous cavity to block progression of cytomegalovirus retinitis.

Heart rate threshold related to lactate turn point and steady-state exercise on a cycle ergometer

The aim of this study was to investigate heart rate threshold (HRT) related exercise intensities by means of two endurance cycle ergometer tests using blood lactate concentration [La], pulmonary ventilation (VE), oxygen uptake (VO2), heart rate (HR) and electromyogram (EMG) activity of working muscle. Firstly, 16 healthy female students [age, 21.4 (SD 2.8) years; height, 167.1 (SD 5.1) cm; body mass 62.7 (SD 7.1) kg] performed an incremental exercise test (10 W each minute) on an electrically braked cycle ergometer until they felt exhausted. The HRT and lactate turn point (LTP) were assessed by means of computer-aided linear regression break point analysis from the relationship of HR or [La] to power output. No significant difference was found between HRT and LTP for all the variables measured. Secondly, two endurance tests (ET) of 20 min duration were performed by 7 subjects. The first (ET I) was performed at an exercise intensity which was about 10% lower than the power output at HRT [61.2 (SD 3.1)% maximal oxygen uptake (VO2max)], the second (ET II) at an exercise intensity about 10% higher than the power output at HRT [79.2 (SD 3.4) % VO2max]. The parameters measured showed a clear steady state in ET I. All mean values were lower than values at HRT [power, 138.7 (SD 18.9) W; HR, 172.1 (SD 4.7) beats.min-1; VO2, 2.2 (SD 0.3) l.min-1; VE, 54.0 (SD 9.1) l.min-1; [La], 3.7 (SD 1.1) mmol.l-1; EMG, 81.1 (SD 24.0) microV] except HR which was the same.(ABSTRACT TRUNCATED AT 250 WORDS)

Correlation between inflection of heart rate/work performance curve and myocardial function in exhausting cycle ergometer exercise

The heart rate/work performance (fc/W) curve is usually S-shaped but a flattening at the top is not always seen. By means of radionuclide ventricular scintigraphy, the left ventricular ejection fraction (LVEF) of 15 sports students was investigated. The behaviour of the fc/W curve during cycle ergometry with increasing exercise intensities was examined. During exercise, the LVEF showed a distinct initial increase reaching roughly constant values at stress levels below-maximum, and sometimes even falling again. The inflections of the fc/W curve and left ventricular ejection fraction/performance curve (LVEFPC) were calculated from a second degree polynomial fit. From this function, the slopes of the tangents at the points of aerobic threshold and maximum performance were calculated together with the differences of the angles as a measure of the fc/W curve and LVEFPC inflections. It follows that the fc/W curve inflection became less pronounced or was even absent altogether when the decrease in LVEF towards the end of the ergometer exercise became more distinct. A significant negative correlation was found between the existence and extent of the fc/W curve inflection and the stress-dependent myocardial function, expressed as the inflection of the LVEFPC (P < 0.01, r = 0.673). Thus, it would seem that the absence of a fc/W curve inflection was related to a diminished stress-dependent myocardial function.

Tumor necrosis factor-alpha, interleukin 1, eicosanoid, and hydrogen peroxide release from macrophages exposed to glove starch particles

The inflammatory mechanisms leading to glove starch powder peritonitis are still unclear. This study was designed to examine the secretory potential of macrophages exposed to starch powder particles. Rat peritoneal macrophages and human monocytes were incubated in vitro with starch particles obtained from three commonly used surgical gloves. It was found that macrophages and monocytes released large amounts of tumor necrosis factor-alpha, interleukin 1, prostaglandin E2, thromboxane B2, and hydrogen peroxide. Release of these inflammatory mediators was associated with progressive cell death of macrophages. These data indicate that postoperative peritonitis and subsequent granuloma formation initiated by glove powder particles may be mediated and maintained, at least in part, by macrophage-derived cytokines, eicosanoids, and reactive oxygen intermediates.

[Neuroleptic low-dose long-term strategy and intermittent therapy strategy in chronic schizophrenia--a critical review]

Much effort has been devoted during the past decade in finding new therapeutic approaches to cope with the commonly occurring adverse side effects of long-term neuroleptic maintenance treatment of schizophrenics, such as, in particular, akathisia, parkinsonian symptoms and tardive dyskinesia. Both low-dose maintenance (e.g. long-term treatment at dosages reduced to one-fifth or even less of conventional dosage levels in remitted and stable schizophrenics) and intermittent or-target medication strategies (e.g. discontinuation of neuroleptics in remitted stable chronic schizophrenics, aimed at resuming the medication as soon as prodromal signs of a relapse or actual relapses occur) might eventually imply for many schizophrenics a substantial reduction in total long-term neuroleptic dosages. This may lead to a reduction in the incidence of side effects and to an improvement in social integration. A critical review of the results published so far arrives at the following conclusions: 1. low-dose maintenance therapy is just as effective as a standard dose regimen and even superior to intermittent (target) medication. Especially if the dosage is increased in case of exacerbations; 2. these results are representative for a very small group of patients only, since the study populations were highly selective.

Effect of 17 beta-estradiol on somatic and germ cell subpopulations in the ovary of the newly hatched chick

The involvement of estrogens in avian ovary differentiation and morphogenesis has been previously demonstrated by several authors. The aim of the present study is to provide evidence regarding which cell subpopulations of the ovary are target cells for 17 beta-estradiol during chick development. White Leghorn chick embryos received 200 ng of the hormone or the vehicle on the chorioallantoic membrane at 11, 13, and 15 days of incubation. Within 24 hr after hatching, the left ovary was processed for total cell count, study of the meiotic prophase of oocytes, and the morphometric evaluation of the cortical and the medullary regions of the ovary. Germ cell number was not modified by the treatment. Similarly, no changes were observed in the stage of the prophase and the cellular area of oocytes. The total number of somatic cells was increased in the newly hatched chick ovary treated with 17 beta-estradiol. The number of undifferentiated cells in the juxtacortical medulla was higher in the treated ovary than in the control group. Moreover, the pregranulosa cells of the cortical region were hypertrophied in the 17 beta-estradiol treated ovary. However, no changes were observed in the typical steroidogenic cells after the estrogen treatment. In conclusion, two subpopulations of somatic cells are estrogen target cells in the prefollicular chicken ovary: the pregranulosa cells of the ovarian cortex and the undifferentiated cells in the juxtacortical medulla.