Comprehensive frailty assessment with multidimensional frailty domains as a predictor of mortality among vascular and cardiac surgical patients

Purpose

The frailty concept has become a fundamental part of daily clinical practice. In this study our purpose was to create a risk estimation method with a comprehensive aspect of patients' preoperative frailty.

Patients and methods

In our prospective, observational study, patients were enrolled between September 2014 and August 2017 in the Department of Cardiac Surgery and Department of Vascular Surgery at Semmelweis University, Budapest, Hungary. A comprehensive frailty score was built from four main domains: biological, functional-nutritional, cognitive-psychological and sociological. Each domain contained numerous indicators. In addition, the EUROSCORE for cardiac patients and the Vascular POSSUM for vascular patients were calculated and adjusted for mortality.

Results

Data from 228 participants were included for statistical analysis. A total of 161 patients underwent vascular surgery, and 67 underwent cardiac surgery. The preoperatively estimated mortality was not significantly different (median: 2.700, IQR (interquartile range): 2.000-4.900 vs. 3.000, IQR: 1.140-6.000, P = 0.266). The comprehensive frailty index was significantly different (0.400 (0.358-0.467) vs. 0.348 (0.303-0.460), P = 0.001). In deceased patients had elevated comprehensive frailty index (0.371 (0.316-0.445) vs. 0.423 (0.365-0.500), P < 0.001). In the multivariate Cox model an increased risk for mortality in quartiles 2, 3 and 4 compared with quartile 1 as a reference was found (AHR (95% CI): 1.974 (0.982-3.969), 2.306 (1.155-4.603), and 3.058 (1.556-6.010), respectively).

Conclusion

The comprehensive frailty index developed in this study could be an important predictor of long-term mortality after vascular or cardiac surgery. Accurate frailty estimation could make the traditional risk scoring systems more accurate and reliable.

Preoperative nutritional state is associated with mid- and long-term mortality after cardiac surgery

BACKGROUND

The frailty score has been developed to determine physiological functioning capacity. The aim of our research was to explore the relationship between frailty factors and mortality in cardiac surgery patients.

METHODS

Our research is an observational, single-center, prospective cohort study (registered on ClinicalTrials.gov: NCT02224222), and we studied 69 patients who underwent elective cardiac surgery between 2014 and 2017. Thirty days before the surgery, they completed a questionnaire that contained questions related to social support, self-reported life quality-happiness, cognitive functions, anxiety and depression. Demographic, anthropometric and medical data were widely collected. The Geriatric Nutritional Risk Index (GNRI) and the Comprehensive Geriatric Assessment (CGA)-based frailty index were calculated as a sum and the domains, respectively. Cox regression and the Kaplan-Meier tests were applied to analyze survival and relative risk. The primary outcome was mid-term mortality.

RESULTS

The patients' mean age was 65.43 years [standard deviation (SD): 9.81 years]. The median followup was 1,656 days of survival [interquartile range (IQR), 1,336-2,081 years], during this period 14 patients died. The median of EuroSCORE II was 1.56 (1.00-2.58) points. The median preoperative albumin level was 32.80 g/L (IQR, 29.9-35.8 g/L). Major adverse cardiovascular and cerebral events (MACCEs) occurred 7 times during follow-up. The nutrition score of the CGA was significantly associated with worse long-term survival [score; hazard ratio (HR): 5.35; 95% CI: 1.10-25.91, P=0.037]. After adjustment for EuroSCORE II and postoperative complications the noncardiovascular CGA score was associated with overall mortality [adjusted hazard ratio (AHR): 1.44, 95% CI: 1.02-2.04, P=0.036]. In the multivariable Cox regression, GNRI <91 showed an increased risk for mortality (AHR: 4.76, 95% CI: 1.52-14.92, P=0.007).

CONCLUSIONS

The CGA-based noncardiovascular score and nutritional status should be assessed before cardiac surgery prehabilitation and may help decrease long-term mortality.

Effects of p.o. administered xylitol in cats

Xylitol is commonly used as sugar substitute in households. While it has numerous beneficial effects on human health, it is highly toxic to dogs. The goal of this study was to examine whether xylitol has similar deleterious effects, such as hypoglycaemia and acute hepatic failure, on cats. Our research included six healthy middle-aged cats. Xylitol was dissolved in deionized water and administered p.o. at three doses (100, 500 and 1,000 mg/kg body weight). These dosages have been considered toxic and can cause liver failure or even death in dogs. After every xylitol administration, the basic health status and the blood glucose of cats were observed regularly. Additionally, prior to and 6, 24 and 72 hr after xylitol administration, blood samples were taken to check complete blood count, clinical biochemical parameters and enzymes such as ALT, ALKP, GGT, GLDH, bile acids, BUN, creatinine, phosphate, total protein, albumin, sodium and potassium. There were no significant changes (p > .05) in any of the haematological or biochemical parameters. Blood glucose concentrations did not show any significant alterations, except at 1,000 mg/kg dose, where a mild but significant increase was observed, but it was in physiological range. Based on our results, xylitol did not induce toxic effects on cats.

Knowledge of Emergency Contraceptive Pills among Hungarian Women Presenting for Induced Abortion or Seeking Emergency Contraception

Aim: To compare the differences in contraceptive characteristics and the knowledge of emergency contraception (ECP) among women who used ECP after unprotected intercourse and those who sought an abortion. Methods: A questionnaire survey was conducted in a Hungarian university hospital among women for whom ECP was prescribed after unprotected intercourse (n = 940) as well as women who presented for the termination of pregnancy (n = 1592) between January 1, 2005 and November 20, 2006. Their knowledge of ECP and their experience with and attitudes toward ECP use were targeted. Results: The availability of ECP was well known (87.9 %), but it was still greatly underutilized: applied by only 13 of the 1592 women who resorted to abortion. Primarily, the ECP group consisted of those who experienced a condom failure significantly more often (odds ratio [OR] = 4.1), followed by those cases where ECP applications was a consequence of not using any kind of contraception (OR = 3.8). Fewer than one third (32 %) of the abortion seekers had previously used ECP, and only one fifth knew how to obtain it. Appropriate awareness of ECP was influenced by information obtained from health-care providers (adjusted odds ratio [AOR] = 3.93) or school education (AOR = 1.82). Conclusions: More thorough education is needed to provide a deeper knowledge of ECP use during contraceptive counseling for women seeking abortion, including those contraceptive mishaps where unintended pregnancy can be prevented by ECP.

Neural mechanisms for lexical processing in dogs

During speech processing, human listeners can separately analyze lexical and intonational cues to arrive at a unified representation of communicative content. The evolution of this capacity can be best investigated by comparative studies. Using functional magnetic resonance imaging, we explored whether and how dog brains segregate and integrate lexical and intonational information. We found a left-hemisphere bias for processing meaningful words, independently of intonation; a right auditory brain region for distinguishing intonationally marked and unmarked words; and increased activity in primary reward regions only when both lexical and intonational information were consistent with praise. Neural mechanisms to separately analyze and integrate word meaning and intonation in dogs suggest that this capacity can evolve in the absence of language.

Extended-spectrum beta-lactamase-producing Klebsiella spp. in a neonatal intensive care unit: risk factors for the infection and the dynamics of the molecular epidemiology

The extended-spectrum beta-lactamase (ESBL)-producing Klebsiella spp. cause worldwide problems in intensive care units. The aim of this study was to investigate the molecular epidemiology of ESBL-producing Klebsiella pneumoniae and K. oxytoca strains in a neonatal intensive care unit (NICU) in Budapest, Hungary and to determine the risk factors of the infections and the epidemiological features. Infections with Klebsiella spp. were analyzed retrospectively by reviewing the medical records between January 2001 and December 2005. Antibiotic susceptibility tests, isoelectric focusing, pulsed field gel electrophoresis, plasmid analysis, PCR for bla(TEM) and bla(SHV) and DNA sequencing analysis were performed on ESBL-producing Klebsiella isolates. A total of 45 babies were found to be infected with non-ESBL-producing Klebsiella spp. and 39 with ESBL-producing Klebsiella spp. Of the parameters analyzed, including sex, gestational age, twin pregnancy, birth weight, presence of central vascular catheter, mechanical ventilator use, parenteral nutrition, polymicrobial infection, caesarean section, transfusion and mortality, we found no statistically significant difference between the ESBL and the non-ESBL groups, or between the K. pneumoniae and K. oxytoca species. Further characterization of the ESBL-producing K. pneumoniae and K. oxytoca strains isolated between February 2001 and January 2003 revealed three distinct PFGE patterns of SHV-5-producing K. pneumoniae (A, B, E) and two distinct patterns of SHV-12-producing K. oxytoca (C,D) isolates; these had different plasmid profiles. From July to November 2005, a new SHV-5 producing K. oxytoca (F) was isolated. The molecular epidemiology of ESBL-producing organisms in a NICU over time shows substantial shifts in predominant strains. The ESBL production of the infected organisms has an impact on the survival of newborn babies with infections caused by Klebsiella spp.

Emergence of extremely high penicillin and cefotaxime resistance and high-level levofloxacin resistance in clinical isolates of Streptococcus pneumoniae in Hungary

Oxacillin disc diffusion tests revealed that 36.7% of 327 Hungarian Streptococcus pneumoniae strains from clinical specimens were not penicillin susceptible. Determination of the MICs of penicillin, cefotaxime and levofloxacin for these strains by Etest confirmed that 30 (9.2%), 19 (5.8%) and four to 11 (1.2-3.4%) were fully penicillin-, cefotaxime- and levofloxacin-resistant, respectively. Most had extremely high MICs. Lower respiratory tract strains were more resistant than those from the upper respiratory tract. Levofloxacin-resistant strains were either penicillin intermediate or resistant, but their MICs did not correlate strongly.

Ellipticine analogues and related compounds as inhibitors of reverse transcriptase and as inhibitors of the efflux pump

Ten polycyclic derivatives related to ellipticine have been synthesised and tested for their intercalating, reverse transcriptase (RT) inhibitory and multidrug resistance efflux pump inhibitory properties. The intercalating activity and the RT inhibitory activity of the derivatives suggest that ellipticine analogues bind at an allosteric binding site on RT or that this inhibition could be controlled at the DNA level. The MDR efflux pump inhibitory activities of these derivatives, however, appears to be unrelated to the DNA binding ability.

In vitro and in vivo activities of amikacin, cefepime, amikacin plus cefepime, and imipenem against an SHV-5 extended-spectrum beta-lactamase-producing Klebsiella pneumoniae strain

The in vitro and in vivo effectiveness of amikacin, cefepime, and imipenem was studied using a high inoculum of an extended-spectrum beta-lactamase-producing Klebsiella pneumoniae strain. An in vitro susceptibility test at the standard inoculum predicted the in vivo outcome of amikacin or imipenem while it did not do so for cefepime due to the inoculum effect.

Effects of naturally occurring glucosides, solasodine glucosides, ginsenosides and parishin derivatives on multidrug resistance of lymphoma cells and leukocyte functions

Solamargine, solasonine, ginsenosides and parishin-related compounds were investigated for their effects on mdr efflux pump of lymphoma cells, and their effects on T cell proliferative assays and cell mediated immune functions, antibody-dependent cellular cytotoxicity (ADCC) and natural killer (NK) cell activity of human peripheral mononuclear cells. Solamargine and solasonine were the only drugs which inhibited all of the tested immune functions; however, ginsenoside Rc and Rd enhanced T cell proliferative assays and marginally increased the NK cell activity. The majority of the compounds were not able to reverse the multidrug resistance of mouse lymphoma cells. However, ginsenosides Rc, Rd and parishin C were able to moderately reduce the activity of the efflux pump. Parishin, parishin C and crude extract significantly enhanced the ADCC reaction.

Exciton coupling in the CD spectra of chiral spiro-lambda 4-sulfanes and related sulfonium salts

Enantiomers of spiro-lambda 4-sulfanes 2-7 and related cyclic sulfonium salts 2c-7c have been obtained by stereospecific synthesis. Exciton splitting was observed in the CD spectra of spiro-lambda 4-sulfanes and sulfonium salts having both benzene and naphthalene-benzene rings. The absolute configurations were deduced from the sign of the couplet. Exciton couplets in the CD spectra of sulfonium salts and their parent lambda 4-sulfanes show the same sign which follows from the same orientation of the coupled electric transition moments due to their similar trigonal bipyramidal geometry. Based on the known stereomechanism of the formation of spiro-lambda 4-sulfanes and sulfonium salts as well as of their hydrolysis leading to the corresponding sulfoxides (2a-7a and 2b-7b), the absolute configurations of sulfoxides could also be deduced from the sign of exciton couplet in the CD spectra of related lambda 4-sulfanes and sulfonium salts.

beta-Lactam susceptibility patterns and investigation of cephalosporin hydrolysing beta-lactamases of Gram-negative extraintestinal clinical isolates

Of more than 3500 isolates of enterobacteriaceae, 48-69% were resistant to aminopenicillins and 11-45% to amoxycillin+clavulanic acid. Resistance to second and third generation cephalosporins was present in 11-17 and 3-8% of Escherichia coli, 47-56 and 15-52% of Klebsiella-Enterobacter, 36-57 and 16-27% of Proteus, Providencia and Morganella isolates. Pseudomonas aeruginosa strains varied in their resistance to antipseudomonal beta-lactams. Isoelectric points, inhibitor profiles and substrate profiles of beta-lactamases extracted from representatives of the resistant strains indicated that the resistance was mainly due to the hyperproduction of chromosomally encoded AmpC beta-lactamases. This was confirmed by plasmid profile and PCR investigations. Extended-spectrum beta-lactamase and metallo-penicillinase producing strains were not found. One Pseudomonas maltophilia strain produced an oxacillinase.

Reversal of multidrug resistance of tumor cells

Drug resistance to chemotherapy is rapidly emerging. Resistance to one drug carries over resistance to unrelated anticancer drugs leading to multidrug resistance (MDR). A major factor of MDR is P-glycoprotein (P-gp) mediated ABC transport found in many eukaryotic cells. P-gp acts as a drug eMux pump. The mdr1 gene involved in P-gp 170 protein production is localized in the human chromosome 7 band p2 1.0-21.1. Point mutations after cross-resistance patterns. A variety of stimuli increase the expression of the mdr1 gene: lowered extracellular pH, heat shock, arsenite, cytotoxic agents, anticancer drugs, transfection with oncogenes, HIV-I, and UV-irradiation. An alternative hypothesis to the efflux pump claims that P-gp modifies the intracellular environment to reduce accumulation of anticancer drugs in cancer cells by creating ionic or proton gradients. Chemosensitizers that block P-gp drug extrusion are generally lipid-soluble at physiological pH, possess a basic nitrogen atom and at least two co-planar rings. P-gp blocking does not depend on drug chirality. This opens the way of treating P-gp related MDR with chiral versions of drugs relatively harmless in terms of side-effects. We believe that resistance modifiers combined with cytostatics will chemotherapeutically be more effective for cancer patients.

Membrane associated antitumor effects of crocine-, ginsenoside- and cannabinoid derivates

In the present work a systematic study was initiated with crocine, ginsenoside and cannabinoid derivatives on multidrug resistant mouse lymphoma cells, viral tumor antigen expression and some human leukocyte functions. Among saffron derivatives, crocin and picrocrocin, triglucosyl and diglucosyl crocetin were ineffective on the reversal of multidrug resistance of lymphoma cells. Ginsenoside increased drug accumulation and tumor antigen expression at 2.0-20.0 micrograms/mL. Some cannabinoid derivatives such as cannabinol, cannabispirol and cannabidiol increased drug accumulation, while cannabidiolic acid, delta-9-THC and tetrahydro-cannabidiolic acid reduced drug accumulation of the human mdr1-gene transfected mouse lymphoma cells. The reversal of multidrug resistance is the result of the inhibition of the efflux pump function in the tumor cells. Crocetin esters were less potent than crocin itself in the inhibition of EBV early antigen expression. However crocin and diglucosylcrocetin inhibited early tumor antigen expression of adenovirus infected cells, but triglucosylcrocetin was less effective at 0.01-1.0 microgram/mL. The crocin had no antiviral effect [on HSV-2 infected vero cells] up to 25 micrograms/mL concentration. Ginsenosides had a moderate inhibitory effect except ginsenoside Rb1 (was the less effective) on the drug efflux pump. Among the cannabinoid derivatives the cannabinol and cannabispirol increased drug accumulation, while cannabidiolic acid and delta-8-THC, delta-9-THC and tetrahydro-cannabinol reduced drug accumulation in multidrug resistant mouse lymphoma cells. It is interesting that ginsenosides had a chemical structure-dependent immunomodulating effect by enhancing the activity of NK-cells and ADCC activities.

Magnetic and Mössbauer Studies of Magnetite-Loaded Polyvinyl Alcohol Hydrogels

Materials producing strain in a magnetic field are known as magnetoelastic or magnetostrictive materials. A new type of material that is able to produce giant strain in a nonhomogeneous magnetic field has been developed. In these magnetic-field-sensitive gels (ferrogels) fine colloidal particles having superparamagnetic behavior are incorporated into a highly swollen elastic polymer network. Magnetic properties of ferrogels have been investigated using electron microscopy, static magnetization measurements, and Mössbauer spectroscopy. Analysis of the data yielded information on the superparamagnetic behavior of ferrogels and made it possible to estimate the size distribution of the magnetic cores of magnetite particles made by chemical precipitation and built into a chemically cross-linked polyvinyl alcohol matrix. The results are interpreted on the basis of a core-shell model. Copyright 2000 Academic Press.

Molecular epidemiology of a cluster of cases due to Klebsiella pneumoniae producing SHV-5 extended-spectrum beta-lactamase in the premature intensive care unit of a Hungarian hospital

Fifteen nosocomial cases of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae occurred among 132 neonates in a premature intensive care unit in Hungary in June through November 1998. Fourteen strains were indistinguishable by molecular biological typing and harbored the same single conjugative extended-spectrum beta-lactamase-encoding plasmid that was spontaneously found in a Serratia marcescens strain in the same patient.

Anti-psychotic drugs reverse multidrug resistance of tumor cell lines and human AML cells ex-vivo

Anti-psychotic drugs are used in cancer patients undergoing chemotherapy frequently and the concomitantly used drugs may alter the pharmacokinetics of each other. One reason for the alteration of pharmacokinetics may be the modulation of the function of P-glycoprotein, whose efflux pump occurs in resistant cancer cells, in human intestine and in the blood-brain barrier. For this reason we tested the effect of several anti-psychotic drugs on the multidrug-resistant pump, P-glycoprotein. We found that in the MDR gene transfected L121C MDR, L5178 MDR and in the KB-V-1 cells selected for resistance some antipsychotic drugs block the function of P-glycoprotein. Blood cells of two treatment-resistant leukemic patients also showed increased uptake of daunorubicin if treated ex vivo with the anti-psychotic drugs. Our results suggest that pharmacokinetic studies should be performed prior to concomitant clinical use of such drugs which block P-glycoprotein function.

The inhibition of SOS-responses and MDR by phenothiazine-metal complexes

The gene of multidrug resistance (mdr) is inducible by different environmental stresses (SOS gene). We tested the inhibitory action of some new metal complexes of phenothiazines on megacin encoding bacterial gene induced by mitomycin-C as an example of "SOS induction" and on efflux pump of mouse lymphoma cells. The interaction of compounds to DNA was measured by thermal stability of DNA. It was found that metal co-ordination complexes of trifluoperazine (TFP) and chlorpromazine (CPZ) added before mitomycin administration have an inhibitory action on megacine induction. The TFP-V(IV) complex was effective at a lower concentration than TFP alone. The inhibitory effect of some metal coordinating complexes (TFP-Cu(II) and TFP- V(IV)) exceeded the action of TFP alone on efflux pumps. We propose that these compounds can form a complex with the regulatory protein or DNA resulting in the inhibition of SOS response and inhibit the mdr function by inactivating the P-glycoprotein as well.

The role of stereoselectivity of chemosensitizers in the reversal of multidrug resistance of mouse lymphoma cells

The effect of three different stereoisomer pairs of CNS (central nervous system) active compounds was studied on the activity of human mdr1 p-glycoprotein. The methotrimeprazine, clopenthixol and butaclamol isomers had an antiproliferative effect (ID50) on the mdr1 expressing cells at 0.250 microgram/ml, while the parental cells were less sensitive having ID50 at 0.37-0.69 microgram/ml. Enantiomers of methotrimeprazine and clopenthixol had similar effectivity on the drug efflux of mdr cells. However, (-)butaclamol was found to inhibit mdr efflux-pump activity much more than the CNS active (+) isomer. Based on these results, tricyclic compounds does not seem to have stereoselectivity in methotrimeprazine and clopenthixol on the mdr reversal effect. In general, both active and inactive members of stereoisomers had a similar effect on the drug accumulation of the mdr cells. Therefore, hypothetically the CNS inactive member of stereoisomer pairs can be used as a resistance modifier without any risk in patients suffering from drug resistant cancer.

Extended-spectrum beta-lactamases: an actual problem of hospital microbiology (a review)

Although there is a variety of mechanisms of bacterial resistance to beta-lactam antibiotics, the most important one is production of beta-lactamases inactivating penicillins and cephalosporins. The classification of beta-lactamases is based on biochemical, enzymological (i.e. molecular structure, inhibitory property, substrate-profile, relative rate of hydrolysis) and immunological characters. Extended-spectrum beta-lactamases (ESBLs) can be derived from TEM or SHV enzymes. These enzymes have now been sequenced and it has been found that relatively few point mutations have occurred in the gene of the TEM and SHV type enzymes. These point mutations clustered in five areas of the gene. The amino acid mutations can alter the conformation, the active site and change the hydrance of beta-lactamase-cephalosporin binding capacity. So the enzyme is able to bind and hydrolyse the third generation cephalosporins. Successive mutation interacted radically increasing the binding capacity of enzymes and confer resistance to newer cephalosporins. The use of these drugs provides a strong selective pressure to develop these mutations. Sporadic nosocomial outbreaks due to strains producing an ESBL led to an epidemic problem in some hospitals resulting in a concurrent dissemination of genes, plasmids or strains. Clinical epidemiological importance and role of ESBLs and emergence of multiply resistance of bacteria of nosocomial importance are discussed in this brief.

Viscosity of rat adrenocortical lipids in different functional states: morphological characteristics

Impaired adrenocortical steroidogenic activity is often concomitant with morphologically and physiologically altered lipids in the cells of the adrenal cortex. The physical state of these lipid droplets and the morphological characteristics of crystal-shaped bodies were studied in different functional states of adrenocortical cells. In the perinatal period when steroidogenesis is suppressed by a negative feedback mechanism, crystal-shaped bodies (i.e. rectangular, electron-lucent formations, either alone or in clusters, surrounded by lysosomal matrix or in close proximity of lysosomes) were frequently observed in the inner zona fasciculata and zona reticularis. In experimentally suppressed adrenocortical activity, following the administration of dexamethasone, aminoglutethimide or cycloheximide, almost identical crystal-shaped bodies were frequently observed in adrenocortical cells. These crystal-shaped bodies appear to be cholesterol, as revealed by the digitonin reaction at the electron microscopic level. Following stimulation of the zona fasciculata by ACTH treatment for 14 days, a marked increase in the fluidity of the lipid droplets was observed in the thermotropic phase transitions with the polarizing microscope. In contrast, following aminoglutethimide treatment, the fluidity of the lipid droplets decreased. The thermotropic phase transitions of normal and neoplastic human adrenal cells, namely adrenocortical tumours causing Conn's or Cushing's syndrome, were also investigated. When hormone biosynthesis was enhanced, the appearance of birefringence and multiple phase transitions of lipid droplets was demonstrable in the low-temperature range.

Effects of joining peptide (1-18) and histamine on dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulphate (DHEAS) production of human adrenocortical cells in vitro

Joining peptide 1-18 (JP 1-18), added alone in concentrations of 10(-13)-10(-7) M to collagenase-dispersed human adrenocortical cells, did not affect the basal production of corticosterone, cortisol, aldosterone, dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulphate (DHEAS). JP 1-18 potentiated the ACTH-stimulated production of steroids. When administered in combination with histamine (10(-8)-10(-3) M), JP 1-18 (10(-8) or 10(-10) M), enhanced the synthesis of DHEA and DHEAS. JP 1-18, together with histamine, may play a role in the regulation of DHEA and DHEAS production.

Dopamine is taken up from the circulation by, and released from, local noradrenergic varicose axon terminals in zona glomerulosa of the rat: a neurochemical and immunocytochemical study

The effect of supramaximal electric field stimulation on [3H]dopamine (DA) release by rat adrenal capsule-glomerulosa preparations was studied using a micro-volume perfusion system. When the tissues were preloaded with [3H]DA, a considerable amount of [3H]DA and [3H]noradrenaline (NA) were released in response to field stimuli. Reserpinization, calcium removal or tetrodotoxin blocking of Na+ influx all completely inhibited the stimulation-evoked release of DA/NA, indicating that the radioactivity released is of neuronal and vesicular origin. In the adrenal cortex, a substantial proportion of tyrosine hydroxylase and dopamine-beta-hydroxylase immunoreactive nerve fibres and varicosities were observed around the zona glomerulosa. DA-containing nerves were not seen in the adrenal cortex; however, the same immunocytochemical procedures clearly demonstrated dopaminergic nerve cells and fibres in the substantia nigra and the striatum respectively, and cells of the adrenal medulla. Like the NA release from noradrenergic varicosities in the zona glomerulosa, the DA release from noradrenergic endings is not subject to negative feedback modulation through DA2 receptors since apomorphine, a DA2-receptor agonist, and sulpiride, a selective DA2-receptor antagonist, failed to affect the release. After in-vivo i.v. administration of [3H]DA, the glomerulosa content of DA and NA and the in-vitro release of [3H]DA and [3H]NA of zona glomerulosa both increased, indicating that the local varicose axon terminals were able to accumulate DA from the circulation, convert it into NA and release it in response to neural activity. This local arrangement of noradrenergic axon terminals, able to take up DA from the circulation and release it or convert it into NA, provides the possibility of a fine tuning of local circulation and aldosterone synthesis in the zona glomerulosa.

Catecholamines released from local adrenergic axon terminals are possibly involved in fine tuning of steroid secretion from zona glomerulosa cells: functional and morphological evidence

The effect of supramaximal electric field stimulation on [3H]noradrenaline (NA) release and hormone production by rat adrenal capsule-glomerulosa preparations was studied using a microvolume perfusion system. A substantial proportion (about 20%) of nerve endings (varicosities) were observed close to zona glomerulosa cells, and about half of them appeared to be catecholaminergic, as judged by the chromaffin reaction of the synaptic vesicles studied at electron microscopic level. In tissue, preloaded with [3H]NA, the release of NA in response to electrical stimulation was frequency-dependent. Reserpinization, calcium removal or inhibition of Na+ influx by tetrodotoxin completely blocked NA release by field stimulation, indicating that the release resulted from axonal activity and is of vesicular origin. Neither the alpha 2-adrenoceptor agonist xylazine nor the muscarine-receptor agonist oxotremorine affected the stimulation-evoked release of [3H]NA, suggesting that, in contrast with other neurones present in the central nervous system or in the peripheral autonomic nervous system but like those in the median eminence, these axon terminals contained few presynaptic modulatory receptors. The NA (10.20 +/- 1.79 (S.E.M.) micrograms/g, n = 9), adrenaline (24.38 +/- 5.50 micrograms/g, n = 9) and dopamine (0.35 +/- 0.09 micrograms/g, n = 6) contents of the preparations were high, as determined by high-performance liquid chromatography. Our observations that the release and content of NA is high, and that a substantial proportion of catecholaminergic axon terminals lie in close proximity to zona glomerulosa cells (median value of the distance 300 nm) or to smooth muscle cells of the vessels, suggest that NA released from local adrenergic neurones without being presynaptically modulated may play an important role in fine-tuning both steroid production and/or blood flow through the gland, itself a powerful modulator of the adrenocortical response. This local modulating effect of NA may be especially significant when sympathetic activity is enhanced.

Changes in adrenocortical lipid fluidity of hyperfunctioning human adrenals

Lipid droplets, the storage places of cholesterol in adrenocortical cells, exhibit a relatively uniform appearance studied by the electron microscope but they are heterogeneous in respect of their optical polarizing properties. Optical birefringency was studied in cryosections of normal and hyperfunctioning adrenal cortex by a polarizing microscope, equipped with a cold/hot stage working in the temperature range from -40 to 40 degrees C. The majority of lipid droplets in normal adrenal cortex were optically anisotropic in each cortical zone at room temperature (22 degrees C) indicating a long-range molecular order of the lipid components. The lipids of the zona glomerulosa, in the cases of Conn's and Bartter's syndromes, became anisotropic when the temperature was lowered below ambient. The birefringency of the lipids of the zona fasciculata in the case of Cushing's disease was observed at temperatures below -10 degrees C indicating ordered packing of the components of lipid droplets at this temperature. Thus the lipids were more fluid in the hyperfunctioning, hormone-producing cells--this may represent an optimal precondition for their mobilization and processing by the hydrolyzing enzyme system. The changes in fluidity of the intracellular lipids can be attributed to different functional states in the adrenal cortex. Study of the thermotropic phase transitions of the lipid droplets by polarizing microscopy may be a useful additional method for the diagnosis of some adrenocortical diseases.

Effect of chronic ACTH treatment on the physical state of lipid droplets in rat adrenocortical cells

A histophysical method has been adapted to determine the thermotropic phase transitions of adrenocortical lipid droplets using a polarizing microscope equipped with a cold/hot stage. Cryosections of freshly-removed, unfixed adrenals, derived from control (untreated), and 14 days ACTH-treated rats were examined. The lipid droplets in the zona fasciculata and zona reticularis of the untreated rats were birefringent at room temperature (22 degrees C). The birefringence of zona glomerulosa lipids selectively increased in the temperature range from -10 to -15 degrees C. In cryosections prepared from ACTH-treated rats, thermotropic phase transitions of the lipid droplets appeared at a temperature range between -30 and -40 degrees C in each cortical zone. The chemical analysis of the isolated lipids revealed that the relative amount of triglycerides in the zona fasciculata lipids increased, while that of free and esterified cholesterol decreased after chronic ACTH treatment. Present data suggest that the increased fluidity of lipid droplets promotes lipid mobilization in response to the enhanced demand of the chronically stimulated adrenocortical cells. Viscosity-dependent mobilization of free cholesterol from lipid droplets is not a rate-limiting process in adrenal steroidogenesis, but rather may represent an important control of the availability of precursor from lipid stores.

Effect of a cholesterol synthesis inhibitor (BM 15.766) in the presence and absence of HDL on corticosteroidogenesis of isolated zona glomerulosa and fasciculata cells

The effect of the cholesterol synthesis inhibitor BM 15.766, 4-[2-[1-(4-chlorocinamyl)piperazin-4-yl]ethyl]-benzoic acid on the corticosteroid production was studied in order to reveal the importance of endogenous cholesterol synthesis in the function of zona glomerulosa and zona fasciculata cells of rats. Attempts were made to compensate the effect of BM 15.766 through the application of high-density lipoproteins (HDL). Electron microscopy was used to trace the binding and intracellular accumulation of colloidal gold-labelled HDL (HDL-Au, a cholesterol carrier), in the presence of the cholesterol biosynthesis inhibitor. The stimulation of both types of cells with ACTH was less effective in the presence of 2 x 10(-5) M BM 15.766. The inhibitory effect of BM 15.766 was most marked on the aldosterone production of the zona glomerulosa cells, and could not be reversed by addition of a small amount of HDL-Au. Corticosterone-aldosterone conversion was inhibited by 2 x 10(-5) M BM 15.766. ACTH-stimulated, short-term HDL uptake and internalization was not affected by the cholesterol synthesis inhibitor. The results suggest that certain metabolites of de novo cholesterol biosynthesis may participate in the control of aldosterone production.

[Determination of placental protein 12 (insulin-like growth factor binding protein 25) in pleural effusion of various origins]

It is reported on the possible role of the radioimmunological estimation of placental protein 12 (PP 12; insulin-like growth factor binding protein 25, IGF-BP 25) in pleural effusions of patients with lung cancer, with pleural carcinosis of extrathoracal carcinomas and benign pleural diseases, respectively. There are more PP 12, IGF-BP 25-positive cases at benign diseases than at carcinomas at all. It is discussed the possible importance of PP 12, IGF-BP 25 as a binding protein of growth factor s IGF-I and -II. The clinical validity should be analysed in more detail on the basis of the estimation of more patients.

Impaired corticosteroid production by isolated adrenocortical cells of hypercholesterolemic rabbits

Changes in the structure and function of rabbit adrenocortical cells were studied eight weeks after cessation of a cholesterol-enriched diet. The plasma cholesterol level of the treated animals was still modestly elevated. All three zones of the adrenal cortex contained a slightly increased number of intracellular lipid droplets, and greater number of lipid-laden macrophages were located in the inner layers, as revealed by light and electron microscopy. The basal and ACTH-stimulated hormone production by the isolated adrenocortical cells were significantly inhibited compared with those of the controls. A possible causal relationship between the inhibited adrenocortical hormone production and the increased number of macrophages is discussed.

Colloidal gold-labeled lipoprotein binding and internalization in adrenocortical cells in vitro

Human (normal and adenomatous) and rat (normal) adrenocortical cells were incubated in vitro with colloidal gold labeled low-density (LDL-Au) and high-density (HDL-Au) lipoproteins, respectively, in order to visualize lipoprotein binding and internalization at an electron microscopic level. Both normal and adenomatous human adrenocortical cells accumulated LDL-Au by receptor-mediated endocytosis via coated pits, coated vesicles, noncoated vesicles, and lysosomes. HDL-Au was not internalized. In rat adrenocortical cells, both HDL-Au and to a lesser extent LDL-Au were internalized. It is concluded that LDL-Au and HDL-Au conjugates can be used to identify lipoprotein receptors and to follow lipoprotein internalization in adrenocortical cells.