Abstract 2324: The role of SERCA pump in cell death and autophagy

The purpose of the study is to elucidate structural and molecular determinants of SERCA inhibition by Thapsigargin (Tg) and related analogs for their effects on intracellular calcium homeostasis, ER stress, cell death and autophagy. Tg specifically binds and blocks the sarco/endoplasmic reticulum Ca2+ ATPase (SERCA), which pumps Ca2+ from the cytosol to the ER. Sustained SERCA inhibition leads to calcium depletion from the ER causing ER stress and ultimately cell death. Recently we showed that Tg-induced calcium perturbation potently blocks autophagy (1). Tg is an attractive potential anti-tumor drug because it effectively kills both slow and fast proliferating cancer cells. However, since Tg is toxic also to normal cells, it must be targeted towards the cancer cells. Replacing a side chain with a linker connecting the Tg core to a peptide prevents Tg from entering cells. Two different linker-peptide sequences have been introduced in clinically tested Tg prodrugs; one is cleaved by PSA, secreted by prostate cancer cells, and the other is cleaved by PSMA, which is secreted by neovascular tissues of a broad range of tumors. The Tg analogs unmasked by the cleavage are able to enter cells and exert their toxic effects. Interestingly, however, in vitro experiments indicate that Tg analogs have different potencies and cellular effects depending on the terminal amino acid residue (2). Exploring why this is the case may lead not only to better Tg prodrug formulations, but also to a deeper understanding of the biological functions of SERCA pump activity. We compare a broad panel of Tg analogs in various cell types for their biological effects. Methods used so far are western blotting, real-time RT-PCR, live-cell imaging, flow cytometry, and assays that measure autophagic sequestration and degradation activity. Our unpublished data indicate the ER-stress sensors PERK, ATF4, CHOP, and IRE1 but not XBP1 and ATF6 to be involved in cell death signaling in LNCaP prostate cancer cells. Moreover, Tg-induced cell death required death receptor 5 and caspase-8. All Tg analogs tested displayed exactly the same molecular requirements for induction of cell death, although some required 5 to 10 times higher doses than Tg to evoke the same strength of death signal. Like Tg (1) the analogs inhibited autophagy before the closure of phagophores, but at higher doses and/or with slower kinetics. These results indicate that thapsigargin and its analogs evoke similar anti-autophagic and death signaling pathways. Further investigations are aimed at exploring the causes for differential potencies, and include measurements of cytosolic and compartmentalized calcium, as well as solving crystal structures of selected analog:SERCA complexes complemented with biophysical studies of analog:SERCA interactions.

References 1. N. Engedal et al., Autophagy 9, 1475 (2013). 2. C. Dubois et al., Febs j 280, 5430 (2013).

Citation Format: Paula Szalai, Morten Luhr, Frank Sætre, Søren B. Christensen, Jesper V. Møller, Poul Nissen, Nikolai Engedal. The role of SERCA pump in cell death and autophagy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2324. doi:10.1158/1538-7445.AM2017-2324

Cranberry Juice and Combinations of Its Organic Acids Are Effective against Experimental Urinary Tract Infection

The antibacterial effect of cranberry juice and the organic acids therein on infection by uropathogenic Escherichia coli was studied in an experimental mouse model of urinary tract infection (UTI). Reduced bacterial counts were found in the bladder (P < 0.01) of mice drinking fresh cranberry juice. Commercially available cranberry juice cocktail also significantly reduced (P < 0.01) bacterial populations in the bladder, as did the hydrophilic fraction of cranberry juice (P < 0.05). Quinic, malic, shikimic, and citric acid, the preponderant organic acids in cranberry juice, were tested in combination and individually. The four organic acids also decreased bacterial levels in the bladder when administered together (P < 0.001), and so did the combination of malic plus citric acid (P < 0.01) and malic plus quinic acid (P < 0.05). The other tested combinations of the organic acids, and the acids administered singly, did not have any effect in the UTI model. Apparently, the antibacterial effect of the organic acids from cranberry juice on UTI can be obtained by administering a combination of malic acid and either citric or quinic acid. This study show for the first time that cranberry juice reduce E. coli colonization of the bladder in an experimental mouse model of urinary tract infection and that the organic acids are active agents.

Differential effects of thapsigargin analogues on apoptosis of prostate cancer cells: complex regulation by intracellular calcium

The inhibition of sarcoplasmic reticulum Ca(2+)-ATPase (SERCA) by thapsigargin (Tg) and Tg-type analogues is considered to trigger cell death by activation of apoptotic pathways. Some of these analogues may be useful as antineoplastic agents after appropriate targeting as peptide conjugated prodrugs to cancer cells. With this in mind, this study evaluates the effect on LNCaP androgen-sensitive cancer cells of thapsigargin substituted with 12-aminododecanoyl linkers and Leu (Leu-8ADT), aspartate (Asp-8ADT) or Boc-8ADT. Our results show that both Leu-8ADT and Asp-8ADT result in rapid ER calcium depletion and an influx of calcium across the plasma membrane by activation of store-operated calcium entry. By contrast, ER Ca(2+) depletion by Boc-8ADT is a very slow process that does not perceptibly increase cytosolic Ca(2+) and activate store-operated calcium entry, because the inhibition of SERCA with this compound is very slow. Nevertheless, we find that Boc-8ADT is a more efficient inducer of apoptosis than both Tg and Leu-8ADT. Compared with Tg and the other analogues, apoptosis induced by Asp-8ADT is very modest, although this compound also activates store-operated calcium entry and at high concentrations (1 μm) causes severe morphological changes, reflecting decreased cell viability. We conclude that many factors need to be considered for optimization of these compounds in antineoplastic drug design. Among these ER stress induced by Ca(2+) endoplasmic reticulum mobilization seems particularly important, whereas the early cytosolic increase of Ca(2+) concentration preceding the executive phase of apoptosis appears to be of no, or little, consequence for a subsequent apoptotic effect.

Effect of high intensity exercise on peak oxygen uptake and endothelial function in long-term heart transplant recipients

Coronary allograft vasculopathy is a well-known long-term complication after cardiac transplantation. Endothelial dysfunction is involved and may be prevented by aerobic exercise. The purpose of this study was to examine whether high intensity aerobic exercise improves peak oxygen uptake (VO(2 peak) ) and endothelial function in heart transplant (HT) recipients. Twenty-seven long-term HT recipients were randomized to either 8-weeks high intensity aerobic exercise or no training. Flow mediated dilation of the brachial artery (FMD) was measured by ultrasound and VO(2 peak) by the analysis of expired air. Blood pressure and biomarkers were measured before and after 8 weeks. VO(2 peak) increased significantly in the exercise group (VO(2 peak) 23.9 ± 1.79 to 28.3 ± 1.63 mL/kg/min compared to controls (VO(2 peak) 24.6 ± 1.38 to 23.4 ± 1.58, p < 0.001 exercise vs. control).FMD increased in the exercise group compared to controls (8.3 ± 1.1% to 11.4 ± 1.2% vs. 5.6 ± 1.0% to 5.3 ± 1.7%, p = 0.024). No increase in nitroglycerin-induced vasodilation was observed. Systolic blood pressure fell in the exercise group (142 ±4.2 mmHg to127 ± 3.4 mmHg, p = 0.01) and was unchanged in controls (141 ± 4.2 mmHg to 142 ±6.4 mmHg, NS). High intensity aerobic exercise reduces systolic blood pressure and improves endothelial function in HT recipients.

A phenylpropanoid, a slovenolide, two sulphur-containing germacranes and Ca2+-ATPase inhibitors from Thapsia villosa

A phenylpropanoid 1, a slovenolide 2, and two germacranes bearing a methylthiopropenoate moiety, 3 and 4, along with twenty known metabolites have been isolated from the roots of Thapsia villosa var. villosa L. The structures of two known phenylpropanoids 5 and 6 have been corrected. Compounds 7 and 8 showed activity as potential inhibitors of the sarco- and endoplasmic Ca(2+)-dependent ATPases (SERCA) pump. Compounds 9, 10 and 11 increased significantly the cytoplasmic free calcium concentration ([Ca(2+)](c)) in human platelets in a concentration-dependent manner.

Isolation of the MAO-inhibitor naringenin from Mentha aquatica L

AIMS OF THE STUDY

To isolate the compound(s) responsible for the MAO-inhibitory activity.

MATERIALS AND METHODS

Six extracts of varying polarity of Mentha aquatica L. were tested in a photometric peroxidase linked MAO bioassay. The 70% ethanol extract had highest inhibitory activity. (S)-Naringenin was isolated from the extract by bioassay guided fractionation on VLC and preparative TLC. The structure of the compound was determined by (1)H, (13)C and (13)C-DEPT NMR and optical rotation.

RESULTS

The IC(50) values for MAO inhibition by naringenin were 342+/-33 microM for the rat liver mitochondrial fraction, 955+/-129 microM for MAO-A and 288+/-18 microM for MAO-B.

CONCLUSIONS

The content of naringenin in Mentha aquatica might explain its use in traditional medicine for depression-like conditions.

Ancistrocladinium A and B, the First N,C-Coupled Naphthyldihydroisoquinoline Alkaloids, from a Congolese Ancistrocladus Species

The isolation and structural elucidation of three novel-type naphthylisoquinoline alkaloids, ancistrocladinium A and B (the latter along with its atropisomer), from a Congolese Ancistrocladus species collected in the habitat Yeteto is reported. Their structures, including all stereochemical features, were elucidated by spectroscopic, chemical, and chiroptical methods. Ancistrocladinium A and B are the first N,C-coupled naphthyldihydroisoquinoline alkaloids found in nature, i.e., with an iminium-aryl axis. Although ancistrocladinium A, which is N,8'-coupled, is configurationally stable at this axis, ancistrocladinum B and its rotational isomer are based on a hitherto unprecedented N,6'-coupling type, with a slow rotation about the hetero biaryl axis at room temperature; they thus occur as a 46:54 mixture of two configurationally semistable atropo-diastereomers. For the isomerization of (P)-ancistrocladinium B to its (M)-diastereomer and for the opposite direction, the Gibbs free energies of activation were determined to be DeltaG double dagger1 = 105.8 kJ mol-1 and DeltaG double dagger2 = 105.7 kJ mol-1, respectively. In addition, the compounds were shown to have promising antileishmanial activities.

Ethnopharmacological evaluation of radal (leaves of Lomatia hirsuta) and isolation of 2-methoxyjuglone

Background

Leaves of Lomatia hirsuta are used in traditional medicine in Chile under the common name of "radal". A tea of radal is traditionally used for treatment of cough, bronchial troubles, and asthma. In a preliminary screening, extracts of the leaves revealed antifungal activity, and the present phytochemical study was undertaken to explain this activity and support the traditional use.

Methods

Along with the traditional tea, extracts of the leaves were screened for antifungal and toxic activities. The profile of secondary constituents was obtained using GC-MS.

Results

2-Methoxyjuglone was isolated from the leaves of Lomatia hirsuta and found to be active against the pathogenic fungus Candida albicans (MIC = 8 μg/mL). Cinnamic acid and vanillic acid were identified as major constituents in the tea by GC-MS. The tea was found not to be toxic against Artemia salina.

Conclusion

The presence of phenolic acids with antimicrobial properties supports the traditional use of Radal, and encourages further studies.

Identification and evaluation of Peruvian plants used to treat malaria and leishmaniasis

Households in eleven geographically and ethnically distinct areas in Loreto, Peru, were interviewed about their knowledge and use of plants, for the treatment of malaria and leishmaniasis. The survey resulted in 988 use records representing 118 plant-taxa for malaria and 289 use-records representing 85 plant-taxa for leishmaniasis. In both cases the 10 most frequently reported taxa accounted for about half of all the use-records. Plant material was collected and extracts were screened for in vitro inhibition of Plasmodium and Leishmania parasites. In the case of Plasmodium, extracts of 11 of the 13 most frequently reported plants showed significant growth inhibitory activity, while only a few plant extracts inhibited the growth of Leishmania parasites.

Synthesis of the thapsigargins

The thapsigargins are a family of complex guaianolides with potent and selective Ca(2+)-modulating properties. This article documents the evolution of a synthetic route through several iterations to a final practical and scaleable synthetic route capable of generating both unnatural and natural products based around the guaianolide skeleton.

Design, synthesis, and pharmacological evaluation of thapsigargin analogues for targeting apoptosis to prostatic cancer cells

A series of thapsigargin (TG) analogues, containing an amino acid applicable for conjugation to a peptide specifically cleaved by prostate-specific antigen (PSA), has been prepared to develop the drug-moiety of prodrugs for treatment of prostatic cancer. The analogues were synthesized by converting TG into O-8-debutanoylthapsigargin (DBTG) and esterifying O-8 of DBTG with various amino acid linkers. The compounds were evaluated for their ability to elevate the cytosolic Ca(2+) concentration ([Ca(2+)](i)) in TSU-Pr1 cells, their ability to inhibit the rabbit skeletal muscle SERCA pump, and their ability to induce apoptosis in TSU-Pr1 human prostatic cancer cells. The activity of analogues, in which DBTG were esterified with omega-amino acids [HOOC(CH(2))(n)()NH(2), n = 5-7, 10, 11], increased with the linker length. Analogues with 3-[4-(L-leucinoylamino)phenyl]propanoyl, 6-(L-leucinoylamino)hexanoyl, and 12-(L-serinoylamino)dodecanoyl were considerably less active than TG, and analogues with 12-(L-alaninoylamino)dodecanoyl and 12-(L-phenylalaninoylamino)dodecanoyl were almost as active as TG. The 12-(L-leucinoylamino)dodecanoyl gave an analogue equipotent with TG, making this compound promising as the drug-moiety of a PSA sensitive prodrug of TG.

[Osteogenesis imperfecta. The effect of intramedullary nails in long tubular bones]

INTRODUCTION

The aim of the study was to describe the clinical, radiological, and functional results of intramedullary nailing of deformities in the lower extremities of children with osteogenesis imperfecta after the use of multiple osteotomies and non-telescoping rods (rush pins).

MATERIAL AND METHODS

Eight children with osteogenesis imperfecta, who consecutively underwent surgery during 1991-1994, were entered in the study.

RESULTS

Sixteen operations were performed on eight children: 12 on the femur and four on the tibia. Like others, we found a high complication rate, 50%. Radiological correction of angular deformities was good. The functional outcome was satisfactory and the patients were satisfied.

CONCLUSION

Correction and stabilisation of deformities in the lower extremities in children with osteogenesis imperfecta with the use of non-telescoping rods is an acceptable method of decreasing fractures and allowing most formerly non-ambulatory children to walk. Furthermore, the cosmetics were improved.

Inhibition of fumarate reductase in Leishmania major and L. donovani by chalcones

Our previous studies have shown that chalcones exhibit potent antileishmanial and antimalarial activities in vitro and in vivo. Preliminary studies showed that these compounds destroyed the ultrastructure of Leishmania parasite mitochondria and inhibited the respiration and the activity of mitochondrial dehydrogenases of Leishmania parasites. The present study was designed to further investigate the mechanism of action of chalcones, focusing on the parasite respiratory chain. The data show that licochalcone A inhibited the activity of fumarate reductase (FRD) in the permeabilized Leishmania major promastigote and in the parasite mitochondria, and it also inhibited solubilized FRD and a purified FRD from L. donovani. Two other chalcones, 2,4-dimethoxy-4'-allyloxychalcone (24m4ac) and 2,4-dimethoxy-4'-butoxychalcone (24mbc), also exhibited inhibitory effects on the activity of solubilized FRD in L. major promastigotes. Although licochalcone A inhibited the activities of succinate dehydrogenase (SDH), NADH dehydrogenase (NDH), and succinate- and NADH-cytochrome c reductases in the parasite mitochondria, the 50% inhibitory concentrations (IC(50)) of licochalcone A for these enzymes were at least 20 times higher than that for FRD. The IC(50) of licochalcone A for SDH and NDH in human peripheral blood mononuclear cells were at least 70 times higher than that for FRD. These findings indicate that FRD, one of the enzymes of the parasite respiratory chain, might be the specific target for the chalcones tested. Since FRD exists in the Leishmania parasite and does not exist in mammalian cells, it could be an excellent target for antiprotozoal drugs.

Absolute configuration and antiprotozoal activity of minquartynoic acid

Minquartynoic acid (1) was isolated as an antimalarial and antileishmanial constituent of the Peruvian tree Minquartia guianensis and its absolute configuration at C-17 established to be (+)-S through conversion to the known (+)-(S)-17-hydroxystearic acid (2) and confirmed using Mosher's method.

[Prevalence of idiopathic scoliosis in the municipality of Hillerod]

Among Scandinavian paediatric spinal surgeons there has been a debate whether the prevalence of idiopathic adolescent scoliosis (AIS) has declined. We examined all children in the town of Hillerød, Denmark attending third and fifth grade (age 10 and 12) with forward-bending-test using a scoliometer. All children with more than seven degrees of trunk inclination were referred to a PA radiogram of the spine. We found a 0.4 percent prevalence of AIS with Cobbangles greater than 19 degrees. This is similar to earlier findings, suggesting that the declining referral rate is due to late detection of idiopathic adolescent scoliosis.

A simple and efficient separation of the curcumins, the antiprotozoal constituents of Curcuma longa

A simple and efficient method for the separation of the three phenolic diketones, curcumin 1, demethoxycurcumin 2, and bis-demethoxycurcumin 3, isolated from the rhizomes of Curcuma longa has been developed. The method is of general applicability for the separation of compounds containing acidic and chelating groups and is amenable to large scale separations. The curcumins 1-3 show moderate activity against Plasmodium falciparum (IC50: 3.5, 4.2 and 3.0 micrograms/ml) and Leishmania major (IC50: 7.8, 14.1 and 21.5 micrograms/ml) respectively.

No increase in fracture incidence in patients treated for thyrotoxicosis in Malmö during 1970-74. A 20-year population-based follow-up

OBJECTIVES

To study whether there is an increased fracture incidence following thyrotoxicosis.

DESIGN

A case-control study.

SETTING

Malmö University Hospital, Malmö, Sweden.

SUBJECTS

All patients (n = 333) from the population of Malmö who were treated for thyrotoxicosis for the first time during the 5-year period 1970-74. A total of 618 controls were selected from the local municipality registry in Malmö. For each case the aim was to randomly select two age- and gender-specific controls, alive in 1993 and born the same year and month as the case.

MAIN OUTCOME MEASURES

Fracture incidence

RESULTS

Comparing survivors, there were no differences in the percentage of individuals with fractures (all, fragility, non-fragility) between the patients and the controls. Comparing all individuals and including all fractures, the percentage of individuals with fractures in the entire female patient group (24.6%) was lower (P < 0.05) than in female controls (33.1%). There was a similar but non-significant pattern between male patients and controls. The mean number of all fractures was lower in male patients than in controls (P < 0.05), but no significant difference was noted between female patients and controls. For fragility fractures, there were no significant differences in the percentage of individuals with fractures or in the mean number of fractures between female or male patients and controls.

CONCLUSION

In conclusion we found no increased incidence of fragility fractures in patients with previous thyrotoxicosis as compared with controls. Our results do not support the suggestion that screening for osteoporosis should be performed in patients with previous thyrotoxicosis.

Thapsigargin analogues for targeting programmed death of androgen-independent prostate cancer cells

A number of analogues of thapsigargin, a selective inhibitor of the sarco-endoplasmic reticulum Ca2+-ATPases have been synthesized. In all of the prepared analogues the butanoyl residue at O-8 has been replaced with a residue containing an aromatic amine. The amine can be used as an anchoring point for attaching a peptide group sensitive to the proteolytic enzyme, prostate specific antigen, secreted by prostate cancer cells. Like thapsigargin, the analogues are capable of elevating the cytoplasmic Ca2+ concentration approximately sevenfold when tested at effective cytotoxic doses. The analogues in which the 8-O-butanoyl group has been replaced with 3-(4-aminophenyl)propanoyl or 4-aminocinnamoyl were found potently to induce programmed cell death of the prostate cancer cells.

The antileishmanial activity of novel oxygenated chalcones and their mechanism of action

Our previous studies have shown that licochalcone A, an oxygenated chalcone, has antileishmanial and antimalarial activities, and alters the ultrastructure and function of the mitochondria of Leishmania spp. parasites. The present study was designed to investigate the antileishmanial activity and the mechanism of action of a group of new oxygenated chalcones. The tested oxygenated chalcones inhibited the in-vitro growth of Leishmania major promastigotes and Leishmania donovani amastigotes. Treatment of hamsters infected with L. donovani with intraperitoneal administration of two oxygenated chalcones resulted in a significant reduction of parasite load in the liver and the spleen compared with untreated control animals. The oxygenated chalcones also inhibited the respiration of the parasite and the activity of mitochondrial dehydrogenases. Electron microscopic studies illustrated that they altered the ultrastructure of the mitochondria of L. major promastigote. The data clearly indicate that this group of oxygenated chalcones has a strong antileishmanial activity and might be developed into a new antileishmanial drug. The antileishmanial activity of oxygenated chalcones might be the result of interference with function of the parasite mitochondria.

Structure-activity studies: in vitro antileishmanial and antimalarial activities of anthraquinones from Morinda lucida

Anthraquinones have been isolated by bioassay-guided fractionation from Morinda lucida. Structure-activity studies show that an aldehyde group at C-2 and a phenolic hydroxy group at C-3 enhance the activity of the anthraquinones against the growth of Plasmodium falciparum and promastigotes of Leishmania major in vitro.

Antiasthmatic activity of the second-generation phosphodiesterase 4 (PDE4) inhibitor SB 207499 (Ariflo) in the guinea pig

We evaluated the airway activity of the novel phosphodiesterase type 4 inhibitor SB 207499 [Ariflo; c-4-cyano-4-(3-cyclopentyloxy-4-methoxyp henyl-r-1-cyclohexane carboxylic acid)], in the guinea pig. Ovalbumin (OA)-induced contractions of guinea pig isolated tracheal strips were inhibited by SB 207499 with an EC50 of 1 microM but had little or no effect on exogenous agonist-induced contraction, which suggests that its effect on OA-induced contraction in vitro is primarily due to inhibition of mediator release from mast cells. In anesthetized guinea pigs, SB 207499 inhibited OA-induced bronchoconstriction with i.v. and p.o. ID50 values of 1.7 and 17 mg/kg, respectively. At 1, 3 and 6 hr after SB 207499 (30 mg/kg p.o.), OA-induced bronchospasm was inhibited by 92%, 70% and 58%, respectively, corresponding to elevated plasma concentrations of 1.62 +/- 0.19, 1.65 +/- 0.29 and 0. 93 +/- 0.24 microg/ml, respectively, of SB 207499. SB 207499 also inhibited house dust mite-induced bronchoconstriction (ID50 = 0.9 mg/kg i.v. and 8.9 mg/kg p.o.). In contrast to its lack of bronchorelaxant activity in vitro, SB 207499 inhibited bronchospasm induced by i.v. leukotriene D4 (LTD4) [ID50 = 3 mg/kg i.v.]. The bronchorelaxant effect of i.v.-administered SB 207499 was at least additive with that of salbutamol in reversing infused histamine-enhanced airway tone, but it did not alter base line or enhance salbutamol-induced cardiovascular effects. In conscious guinea pigs, SB 207499 (10 or 30 mg/kg p.o.), 1 hr before antigen or LTD4 challenge, markedly reduced bronchospasm and subsequent eosinophil influx as measured by bronchoalveolar lavage 24 hr after provocation. SB 207499 administered after OA or LTD4 challenge also reduced airway eosinophilia measured at 24 hr after OA challenge or 96 hr after LTD4 challenge. These results, coupled with the broad anti-inflammatory activity of SB 207499 previously described (Barnett et al., 1998), suggest that SB 207499 will be useful in the treatment of asthma and other inflammatory disorders.

Antileishmanial chalcones: statistical design, synthesis, and three-dimensional quantitative structure-activity relationship analysis

A large number of substituted chalcones have been synthesized and tested for antileishmanial and lymphocyte-suppressing activities. A subset of the chalcones was designed by using statistical methods. 3D-QSAR analyses using 67 (antileishmanial activity) and 63 (lymphocyte-suppressing activity) of the compounds for the training sets and 9 compounds as an external validation set were performed by using the GRID/GOLPE methodology. The Smart Region Definition procedure with subsequent region selection as implemented in GOLPE reduced the number of variables to approximately 1300 yielding 3D-QSAR models of high quality (lymphocyte-suppressing model, R2 = 0. 90, Q2 = 0.80; antileishmanial model, R2 = 0.73, Q2 = 0.63). The coefficient plots indicate that steric interactions between the chalcones and the target are of major importance for the potencies of the compounds. A comparison of the coefficient plots for the antileishmanial effect and the lymphocyte-suppressing activity discloses significant differences which should make it possible to design chalcones having a high antileishmanial activity without suppressing the proliferation of lymphocytes.

ACTA, a fluorescent analogue of thapsigargin, is a potent inhibitor and a conformational probe of skeletal muscle Ca2+-ATPase

Thapsigargin is a highly potent and selective inhibitor of sarco-endoplasmic reticulum (SERCA) family of Ca2+-ATPases and a useful tool in research concerning the function of intracellular Ca2+ stores. We describe here a novel fluorescent derivative (8-O-(4-aminocinnamoyl)-8-O-debutanoylthapsigargin, termed ACTA) of this compound, acting as a Ca2+-ATPase inhibitor with a potency approaching that of thapsigargin. Binding of ACTA to the skeletal muscle sarcoplasmic reticulum vesicles results in a strong fluorescence enhancement, approximately 66% of which depends on ACTA association with Ca2+-ATPase. This specific component of ACTA fluorescence is sensitive to the E1-E2 conformational equilibrium of the pump. The combined properties of high potency and binding-dependent fluorescence suggest ACTA to be a useful probe for a range of studies involving the SERCA class of ATPases.

Modifications of the alpha,beta-double bond in chalcones only marginally affect the antiprotozoal activities

Methods for selective alkylation of chalcones in the alpha- or beta-position and for selective reduction of the alpha,beta-double bond have been developed. The antiparasitic potencies of the alpha,beta-double bond modified chalcones only differ marginally from the potencies of the parent chalcones indicating that the propenone residue only functions as a spacer between the two benzene rings, which are the true pharmacophore.

Living with breast cancer: care givers' perceptions in a surgical ward

Caring for women with breast cancer has potential for increasing care giver distress and anxiety. Knowledge of the threats implicit in the disease and treatment as well as overidentification with the patient form the basis for this outcome. In order to describe perceptions of breast cancer as an illness, semistructured interviews were carried out with 37 care givers at a surgical department. The interviews were tape-recorded and transcribed verbatim. An analysis was then carried out of the stories told by the care givers about breast cancer as an illness. The results indicated that breast cancer as an illness gave rise to predominantly negative and dark associations among the care givers. Their experiences of caring for women in critical stages of the illness over many years appear to have had a negative influence on them. Death itself, and even more so the process leading to the end, were very tangible in their stories. The article concludes that care givers on a surgical ward have a fragmented picture of the patients and need to be given opportunities to follow the total care process. Those care givers who were able to follow the women's stages of illness throughout more often had a positive picture.

[Admission pattern at a department of internal medicine. Factors of significance for readmission within three months after discharge]

The aim of the study was to investigate factors of significance for readmission of patients in a department of internal medicine. The study was based on hospital computerized data files. All admissions from the 1st of January to the 31st of December 1995 were included. During that period the department had 6061 admissions of 4152 patients. The readmission rate was 1.46. All patients were followed three months after discharge. Within that period 1119 (27%) of the patients were readmitted. A high frequency of readmission was especially found within the first ten days after discharge. Length of stay in hospital did not influence readmission rate. Women, patients in the age group 71-90 years and patients with chronic diseases were more likely to be readmitted. The demonstrated factors relating to a high readmission rate are difficult to influence. A prospective study including the primary health care system and a clinical evaluation of the patients is needed to examine causes of the high number of readmission within the first ten days after discharge.

Rapid increase in volume of the remnant after hemithyroidectomy does not correlate with serum concentration of thyroid stimulating hormone

OBJECTIVE

To study the effect of postoperative thyroxine on the volume of the thyroid remnant after lobectomy for benign nontoxic goitre.

DESIGN

Prospective, randomised study.

SETTING

University hospital, Sweden.

SUBJECTS

50 consecutive patients who underwent lobectomy for benign non-toxic goitre.

INTERVENTIONS

Patients were randomised postoperatively to take thyroxine 0.1 mg or placebo daily.

MAIN OUTCOME MEASURES

The median volume of the remaining thyroid lobe measured by ultrasound. Serum concentrations of thyroxine, triiodothyronine (T3) and thyroid stimulating hormone (TSH) were measured preoperatively and 1, 3, 6, 12 months postoperatively.

RESULTS

The median volume of the remaining lobe had increased significantly compared with preoperatively by 1 month postoperatively by 30% in the thyroxine group and 25% in the placebo group (p < 0.01). The difference between the groups was not significant. After the first month the volume did not change significantly. In the thyroxine group, the TSH concentration was unchanged and the thyroxine concentration increased significantly throughout the study. In the placebo group there was a significant increase in TSH concentration and a significant decrease in that of thyroxine at all follow-up examinations.

CONCLUSIONS

There is a significant increase in the volume of the remaining thyroid 1 month after lobectomy that persisted throughout the first year. Thyroxine given in a dose that kept the serum TSH concentration at the same level as preoperatively did not seem to influence volume changes; consequently we consider that these are caused by factors other than TSH.

A tool coming of age: thapsigargin as an inhibitor of sarco-endoplasmic reticulum Ca(2+)-ATPases

Thapsigargin is the most widely used inhibitor of the ubiquitous sarco-endoplasmic reticulum Ca(2+)-ATPases in mammalian cells. Over the past ten years, this guaianolide compound of plant origin has become a popular tool in a host of studies directed at elucidating the mechanisms of intracellular Ca2+ signalling. Its remarkable potency and selectivity have been instrumental in widening our view of the function of intracellular Ca2+ stores to include such key aspects as store-operated Ca2+ entry or the involvement of the stores in protein synthesis or cell growth. In this article Marek Treiman, Casper Caspersen and Søren Brøgger Christensen review the key pharmacological features of thapsigargin action; they also discuss some of the ways in which its unique properties have shown to be important for obtaining new insights into the biology of Ca2+ stores, and how these properties might encompass a therapeutic potential. In parallel, attention is drawn to some of the limitations and pitfalls encountered when working with thapsigargin.

1,4-Cyclohexanecarboxylates: potent and selective inhibitors of phosophodiesterase 4 for the treatment of asthma

Evaluation of a variety of PDE4 inhibitors in a series of cellular and in vivo assays suggested a strategy to improve the therapeutic index of PDE4 inhibitors by increasing their selectivity for the ability to inhibit PDE4 catalytic activity versus the ability to compete for high affinity [3H]rolipram-binding sites in the central nervous system. Use of this strategy led ultimately to the identification of cis-4-cyano-4-[3-(cyclopentyloxy)-4-methoxyphenyl]cyclohexane-1-carboxyl ic acid (1, SB 207499, Ariflo), a potent second-generation inhibitor of PDE4 with a decreased potential for side effects versus the archetypic first generation inhibitor, (R)-rolipram.

SB 207499 (Ariflo), a potent and selective second-generation phosphodiesterase 4 inhibitor: in vitro anti-inflammatory actions

First-generation phosphodiesterase 4 (PDE4) inhibitors, such as rolipram, inhibit the activation of immune and inflammatory cells. The clinical use of these compounds is limited by gastrointestinal side effects, such as increased acid secretion and nausea. Consequently, the challenge has been to design novel PDE4 inhibitors that maintain the anti-inflammatory actions of rolipram while achieving an improved side effect profile. Among the first of this new class of PDE4 inhibitors specifically designed to have an improved therapeutic index relative to earlier compounds is SB 207499 (Ariflo) [c-4-cyano-4-(3-cyclopentyloxy-4-methoxy-phenyl)-r-1-cyclohexanecarboxyl ic acid]. In this study, we compared the anti-inflammatory and gastric secretogogue activities of SB 207499 with those of rolipram. The cellular models used were (1) histamine release from human basophils, (2) tumor necrosis factor-alpha generation in human monocytes, (3) degranulation of human neutrophils, (4) antigen-driven proliferation and cytokine synthesis from human T cells and (5) acid secretion from isolated rabbit gastric glands. SB 207499 inhibited the activation of a variety of immune and inflammatory cells in a concentration-dependent manner: (1) histamine release in basophils [-log IC25 = 6.6 +/- 0.3 vs. 8.0 for (R)-rolipram], (2) lipopolysacchride-induced TNF-alpha formation in monocytes [-log IC50 = 7.0 +/- 0.1 vs. 7.2 +/- 0.1 for (R)-rolipram], (3) fMLP-induced degranulation in neutrophils [-log IC15 = 7.1 +/- 0.2 vs. 6.4 +/- 0.5 for (R)-rolipram], (4) house dust mite induced-proliferation of peripheral blood mononuclear cells [-log IC40 = 6.5 +/- 0.3 vs. 6.4 +/- 0.3 for (R)-rolipram] and (5) ragweed-induced production of interferon-gamma [-log IC50 = 5.4] and interleukin-5 [-log IC50 = 5.0]. Although SB 207499 inhibits the activation of a variety of immune and inflammatory cells with a potency equal to that of rolipram, it is > 100-fold less potent than the latter compound as an acid secretagogue [-log EC50 = 6.1 +/- 0.1 vs. 8.3 +/- 0.2 for (R)-rolipram]. Collectively, these data indicate that SB 207499 retains the anti-inflammatory activity of the prototypical PDE4 inhibitor rolipram but is substantially less likely to stimulate gastric acid secretion.

Evaluation of a hospital-based palliative support service with particular regard to financial outcome measures

The object of this study was a financial assessment of a hospital-based palliative support service, to be made by comparing the study group with a matched historical control group and a group of contemporary reference patients. The staff consisted of one full-time nurse supported by a surgeon one half-day per week. The patients in the study group utilized fewer institutional days than the control group, according to such parameters as duration of terminal hospitalization (P < 0.05), ratio of days at home to total inclusion days (P < 0.001), and days at home during last two months of life (P < 0.01). These three outcome measures all focus on the most care-intensive last months of life and appeared to be sensitive enough to identify economic advantages of palliative care intervention. The palliative support service defrayed its own costs and in excess of that saved another SK17000 per patient (US$2500).

Antiprotozoal compounds from Asparagus africanus

Two antiprotozoal compounds have been isolated from the roots of Asparagus africanus Lam. (Liliaceae), a new sapogenin, 2 beta, 12 alpha-dihydroxy-(25R)-spirosta-4,7-dien-3-one (1), which was named muzanzagenin, and the lignan (+)-nyasol (2), (Z)-(+)-4,4'-(3-ethenyl-1-propene-1,3-diyl)-bisphenol. The structure of the sapogenin was elucidated by MS and by 1D and 2D NMR methods and established by a single crystal X-ray analysis. (+)-Nyasol potently inhibits the growth of Leishmania major promastigotes, the IC50 being 12 microM, and moderately inhibits Plasmodium falciparum schizonts with the IC50 49 microM. These concentrations only moderately affect the proliferation of human lymphocytes. Muzanzagenin showed a moderate in vitro activity in all three tests, the IC50 against leishmania promastigotes was 70 microM, and against four different malaria schizont strains the IC50 values were 16, 163, 23, and 16 microM, respectively.

New anti-HIV-1, antimalarial, and antifungal compounds from Terminalia bellerica

A bioactivity-guided fractionation of an extract of Terminalia bellerica fruit rind led to the isolation of two new lignans named termilignan (1) and thannilignan (2), together with 7-hydroxy-3',4'-(methylenedioxy)flavan (3) and anolignan B (4). All four compounds possessed demonstrable anti-HIV-1, antimalarial, and antifungal activity in vitro.

Synthesis, isolation and identification of glucuronides and mercapturic acids of a novel antiparasitic agent, licochalcone A

1. Four glucuronic acid conjugates of licochalcone A (Lica), and their metabolites, have been synthesized using rabbit and pig liver microsomes and purified by preparative hplc. 2. The glucuronides were identified as E-Lica 4'-O-beta-glucuronide, E and Z-Lica 4-O-beta-glucuronide and a mono-glucuronide conjugate of a beta-hydroxylated Lica metabolite. The metabolites were identified by hplc-nmr (one and two-dimensional nmr) as well as hplc-ms. 3. At pH 8.5 Lica reacted with N-acetyl-L-cysteine giving the two epimeric conjugates, which were then isolated by preparative hplc and identified by one and two-dimensional nmr spectroscopic methods. 4. Only two glucuronic acid conjugates (E- and Z-Lica 4-O-beta-glucuronide) were found in the urine of rat after i.p. administration of a single dose of Lica.

[Experience with daily single dose administration of gentamicin]

The purpose of the study was to evaluate the effect and side-effects of once daily (OD) administration of gentamicin. The study was a retrospective analysis of patients treated with gentamicin OD for at least two days for proven or suspected infection. Of the 101 patients included, 60 were female, and the median age was 64 years (range: 20-90 years). Median duration of treatment was six days (2-63 days). All patients received combination therapy with two (36 patients), three (64 patients) or four (one patient) antibiotics, apart from gentamicin usually ampicillin, cefuroxime and/or metronidazole. Gentamicin doses were usually 240 mg on a fixed basis, but reduced in patients with pre-treatment impairment of serum-creatinine. Bacteriological cultures were taken in 90% of the patients, of which 59% were positive, most often with Enterobacteriaceae (57%) or other Gram-negative rods (11%). Effect of antibiotic treatment was seen in 82% of the patients. Nephrotoxicity defined as a 44 umol/l increase in serum-creatinine during treatment was found in five patients (5%). Ototoxicity, i.e. clinical signs of tinnitus, dizziness and/or impaired hearing, was reported in two patients. In conclusion, gentamicin OD with 240 mg is easy to administer, appears to be sufficient with regard to effect and has a low frequency of side-effects.

Two new antiprotozoal 5-methylcoumarins from Vernonia brachycalyx

Two new isomeric 5-methylcoumarins, 2'-epicycloisobrachycoumarinone epoxide (1) and cycloisobrachycoumarinone epoxide (2), have been isolated from the roots of Vernonia brachycalyx by means of bioactivity-guided fractionation. The structures were elucidated by MS and NMR spectroscopic methods. Compounds 1 and 2 showed in vitro activity against Leishmania major promastigotes and against Plasmodium falciparum schizonts and demonstrated an inhibition on the proliferation of human lymphocytes, which was significantly weaker than the antiparasitic effects.

Medical care utilization by incurable cancer patients in a Swedish county

A retrospective study of patients with cancer diagnoses treated at a Swedish county hospital was carried out in order to analyse medical care utilization by incurable cancer patients. All 208 patients customarily treated at the Department of General Surgery in Ostersund Hospital for cancer diagnoses during 1 year were included in the study. The main outcome measures were: number of institutional days; admissions; duration of terminal hospitalization. The Department of General Surgery supplied 7570 of all 12,276 (62%) institutional days needed throughout the disease course. The terminal hospitalization (i.e. the period of continuous institutional care ending with the death of the patient) constituted 39% of all institutional days. The duration of the terminal hospitalization seemed to be unrelated to various diagnoses and demographic variables. Patients with cancer of the breast utilized most institutional days/patient (median 80 institutional days) during the disease course. Married patients and patients living within a 40 km radius of the hospital spent significantly more days at the Department of General Surgery during the last 6 months of life than did the unmarried and those living further afield.

Place of death correlated to sociodemographic factors. A study of 203 patients dying of cancer in a rural Swedish county in 1990

The purpose of this study was to ascertain where patients with malignant disease died and to establish whether such factors as age, sex, marital status, place of residence, diagnosis and interval between diagnosis and death bore any relation to the place of death. All medical records of 203 patients who died in one particular Swedish county in 1990 of cancers of the GI tract, the urogenital organs, the breast, the skin and the thyroid were analysed. Of all 203 patients, 25 (12%) died at home, 49 (24%) in nursing homes and 129 (64%) in hospital. The proportion of home deaths was significantly smaller when the interval from diagnosis to death was less than one month. Death in a nursing home, compared with death in a hospital, was more usual among patients older than 80 years, among those living more than 40 km from the hospital and among those from areas where the local health care centre had a nursing home attached.

Association of the anti-inflammatory activity of phosphodiesterase 4 (PDE4) inhibitors with either inhibition of PDE4 catalytic activity or competition for [3H]rolipram binding

Phosphodiesterase 4 (PDE4) inhibitors are novel anti-inflammatory compounds. Unfortunately, the archetypal PDE4 inhibitor rolipram produces central nervous system and gastrointestinal side-effects. To exploit these agents, we need to identify PDE4 inhibitors that retain the anti-inflammatory activity with a reduced potential to elicit unwanted side-effects. PDE4 possesses both cyclic AMP catalytic activity that is inhibitable by rolipram and a high affinity binding site for rolipram. The function of this high affinity rolipram binding site is unclear; however, certain pharmacological effects of PDE4 inhibitors are associated with competition for this site. Since PDE4 inhibitors suppress both monocyte and neutrophil activation, the present experiments were carried out to establish a correlation between suppression of monocyte activation [tumor necrosis factor alpha (TNF alpha) formation] or suppression of neutrophil activation (degranulation) with inhibition of either PDE4 catalytic activity or [3H] rolipram binding. Suppression of TNF alpha formation demonstrated a strong correlation with inhibition of PDE4 catalytic activity (r=0.87; P<0.01; Spearman's Rho = 0.79, P<0.05), whereas there was no correlation with inhibition of [3H]rolipram binding(r=0.21, P>0.5; Spearman's Rho=0.16, P>0.5). Suppression of neutrophil degranulation was not associated with inhibition of PDE4 catalytic activity (r=0.25, P>0.4; Spearman's Rho=0.33, P>0.2), but was associated with inhibition of [3H]rolipram binding (r=0.68, P<0.05; Spearman's Rho=0.6, P=0.06). These results indicate that anti-inflammatory effects of PDE4 inhibitors can be associated with either inhibition of PDE4 catalytic activity or high affinity rolipram binding.

Angiotensin converting enzyme (ACE) inhibitory flavonoids from Erythroxylum laurifolium

In our screening program for antihypertensive properties of plants in traditional use, the 99% ethanol extract of Erythroxylum laurifoiium leaves showed interesting angiotensin converting enzyme (ACE) inhibitory activity. The activity was found to be due to proanthocyanidins or condensed tannins and the flavonoids quercetin-3-O-rhamnoside (quercitrin) (IC(50) = 0.67 mM) and kaempferol-3-O-rhamnoside (afzelin) (IC(50) = 2.8 mM). In addition, quercitrin with afzelin demonstrated in vitro synergistic ACE inhibitory activity.

The antileishmanial agent licochalcone A interferes with the function of parasite mitochondria

Our previous studies have shown that licochalcone A, an oxygenated chalcone, has antileishmanial (M. Chen, S.B. Christensen, J. Blom, E. Lemmich, L. Nadelmann, K. Fich, T.G. Theander, and A. Kharazmi, Antimicrob, Agents Chemother. 37:2550-2556, 1993; M. Chen, S.B. Christensen, T.G. Theander, and A. Khrazmi, Antimicrob. Agents Chemother. 38:1339-1344, 1994) and antimalarial (M. Chen, T.G. Theander, S.B. Christensen, L. Hviid, L. Zhai, and A. Kaharazmi, Antimicrob. Agents Chemother. 38:1470-1475, 1994) activities. We have observed that licochalcone A alters the ultrastructure of the mitochondria of Leishmania promastigotes (Chen et al., Antimicrob. Agents Chemother. 37:2550-2556, 1993). The present study was designed to examine this observation further and investigate the mechanism of action of antileishmanial activity of licochalcone A. Electron microscopic studies showed that licochalcone A altered the ultrastructure of Leishmania major promastigote and amastigote mitochondria in a concentration-dependent manner without damaging the organelles of macrophages or the phagocytic function of these cells. Studies on the function of the parasite mitochondria showed that licochalcone A inhibited the respiration of the parasite by the parasites. Moreover, licochalcone A inhibited the activity of the parasite mitochondrial dehydrogenase. The inhibition of the activity of the parasite mitochondrial enzyme correlated well with the changes in the ultrastructure of the mitochondria shown by electron microscopy. These findings demonstrate that licochalcone A alters the ultrastructure and function of the mitochondria of Leishmania parasites.

Inhibitors of phosphodiesterase IV (PDE IV) increase acid secretion in rabbit isolated gastric glands: correlation between function and interaction with a high-affinity rolipram binding site

In this report, we describe the ability of selective inhibitors of phosphodiesterase (PDE) isozymes to increase aminopyrine accumulation in rabbit isolated gastric glands. Aminopyrine accumulation in the presence of histamine was increased by the nonselective PDE inhibitor isobutylmethylxanthine (EC50 = 4.8 microM) and by two selective PDE IV inhibitors, rolipram and Ro 20-1724 (EC50 = 0.013 and 0.07 microM, respectively) but not by selective PDE III inhibitors (siguazodan and SK&F 94120) or by a selective PDE V inhibitor (zaprinast). These results suggest that PDE IV is an important regulator of acid secretion in response to histamine. One of the more fascinating properties of PDE IV is the expression of a high-affinity binding site for [3H]-rolipram in addition to cAMP catalytic activity. Although agents that inhibit PDE IV catalytic activity also appear to bind to the high-affinity rolipram-binding site, the rank-order potencies of compounds for these two effects are poorly correlated. Also, certain pharmacological actions of PDE IV inhibitors appear to be related to an interaction with this binding site. In this study, we observed that the ability of PDE IV inhibitors to enhance acid secretion was not associated with their ability to inhibit PDE IV catalytic activity but did show a strong correlation with their ability to compete for [3H]-rolipram binding. Furthermore, we were able to detect [3H]-rolipram binding sites in gastric glands that had characteristics similar to those of the [3H]-rolipram binding sites in rat brain microsomes and human recombinant PDE IV.