Novel splice isoforms of STRADalpha differentially affect LKB1 activity, complex assembly and subcellular localization

STRADalpha is a pseudokinase that forms a heterotrimeric complex with the scaffolding protein MO25 and the tumor suppressor serine threonine protein kinase LKB1. Mutations in the LKB1 gene are responsible for the Peutz-Jeghers Syndrome (PJS) characterized by a predisposition to hamartomatous polyps and hyperpigmentation of the buccal mucosa. Mutations in LKB1 have also been observed in some sporadic tumours unrelated to PJS. The LKB1/STRAD/MO25 complex is involved in the regulation of numerous signaling pathways including metabolism, proliferation and cellular polarity of human intestinal epithelial cells. Cell polarization, together with tissue-restricted transcription, represents the main feature of enterocyte differentiation. Since a full-length STRADalpha transcript has not been identified thus far in these cells, we evaluated the expression of endogenous STRADalpha in five colorectal cancer cell lines characterized by their diverse ability to differentiate in vitro. We report herein the discovery of several novel splice isoforms of STRADalpha that differentially affect the kinase activity, complex assembly, subcellular localization of LKB1 and the activation of the LKB1-dependent AMPK pathway.

[Cell therapies in cardiology: results from the first randomized clinical trials]

Following acute myocardial infarction, necrotic cardiac tissue is replaced by scar leading to ventricular remodeling and pump failure. Transplantation of autologous bone marrow-derived cells into the heart, early post-infarct, aims to prevent ventricular remodeling. This strategy has been evaluated in four controlled, randomized clinical trials, which provided mixed results. A transient improvement in ventricular function was observed in one trial, and a modest improvement (the duration of which remains to be determined) in an additional trial, whereas two trials showed negative results. A modest benefit of bone marrow cell transplantation was also observed in patients with chronic ischemic heart disease. Despite mixed results reported so far, cell therapy of heart disease still is in its infancy and has considerable room for improvement.

Genealogy of centenarians and their relatives: a study of 12 families

The longevity is a complex phenomenon in which specific genetic properties seem to play a role. The present study intended to reconstruct the genealogical tree of 12 subjects, being residents of one Northern and one Southern province of Italy, in order to establish the longevity of the ancestors. Detailed studies have been performed in the registry offices and the historic archives. The research method started from the identification of the centenarians on the basis of the documentation of the relevant birth document, it was continued by identifying the documents of birth, marriages and death of the parents of the centenarians. This way we proceeded systematically backwards in time. In addition, we verified the medium life span of the Italian population in the given periods of time, when the centenarians and their ascending lines had lived. These results offer clear historic-statistical evidences for the genetic basis of longevity.

Academic education's contribution to the nurse-patient relationship

AIM

To explore how nursing students perceive the role of academic education in enabling them to understand factors that can influence the relationship between nurses and patients.

METHOD

An exploratory qualitative design, with data collected through unstructured interviews with four pre-registration students enrolled on a degree course in adult nursing.

FINDINGS

Participants emphasised the role of reflection in making academic education relevant to practice and in promoting understanding of the relationships they developed with patients. They also valued experiential learning methods used in seminars, for example, case studies, role play and group discussion.

CONCLUSION

Academic education plays an important role in fostering understanding of the nurse-patient relationship by promoting a learning approach based on reflection and self-awareness.

No effect of atypical antipsychotic drugs on weight gain and risk of developing type II diabetes or lipid abnormalities among nursing home elderly patients with Alzheimer's disease

AIM

Weight gain and the risk of developing alterations in lipid and glucose metabolism are possible side effects of atypical antipsychotic therapy in young and adult patients. The objective of this study was to examine whether elderly patients with Alzheimer's disease (AD) gain weight or develop disturbances in lipid and glucose metabolism while being treated with atypical antipsychotic drugs.

METHODS

This retrospective study identified 36 out of 99 patients (mean age: 75.4+/-7.1, 27 female, 9 males) who were taking risperidone (N=9, mean dosage: 1.42+/-0.49 mg/day), olanzapine (N=17: 4.42+/-1.10 mg/day), and quetiapine (N=10: 75+/-27 mg/day) over a 12 months period. Anthropometric parameters, mini nutritional assessment (MNA), total, HDL and LDL cholesterol, triglycerides, glycaemia were assessed at baseline (T0) and 12 (T1) months.

RESULTS

Body weight (BMI=23+/-5 vs 23+/-5), MNA score (21+/-4 vs 21+/-4), blood glucose (5.7+/-2 vs 4.9+/-0.9 mmol/L) or total cholesterol (4.9+/-1.1 vs 4.3+/-0.7 mmol/L), HDL cholesterol (1.3+/-0.3 vs 1.1+/-0.3 mmol/L), LDL cholesterol (3.3+/-0.7 vs 3 +/- 0.4 mmol/L), triglycerides (1.1+/-0 vs 1+/-0.3 mmol/L) did not reveal treatment-induced changes in the patients evaluated (T0 vs T1).

CONCLUSION

These results suggest that the treatment with low-dose of atypical antipsychotic drugs is not associated with weight gain or increase the risk of developing type II diabetes or abnormalities of lipid metabolism among elderly patients with AD, who were residing in long-term nursing home.

Hg(II)-coordination by sugar-acids: Role of the hydroxy groups

A solution study on the ability of some derivatised sugars [glucuronic acid (GluA), galacturonic acid (GalA) and glucosaminic acid (GlNA)] to complex the Hg(II) ion is reported. The stability constants of the complex species were determined by potentiometric measurements while (1)H NMR experiments allow to define the coordination sites of sugar molecules. GluA coordinates the metal ion through the carboxylic oxygen and the O-4 hydroxyl group and is found to form more stable complexes with respect to GalA in which metal ligation is from the carboxylic oxygen and the O-5 ring oxygen. GlNA forms stable complexes chelating Hg(II) ion through carboxylic oxygen and the alpha-amino group. The ternary 2,2'-bipyridine containing systems were also investigated by means of potentiometric studies. The ML(2) complexes were also isolated in the solid state and characterised by IR spectroscopy.

Understanding the Polymorphic Behavior of Sibenadet Hydrochloride through Detailed Studies Integrating Structural and Dynamical Assessment

Three polymorphs of sibenadet hydrochloride (AR-C68397AA, Viozan) have been shown to exist at ambient temperature and have been characterized. Each undergoes a solid-state transition to a common high temperature form, which melts at approximately 220 degrees C. X-ray powder diffraction (XRPD) indicates that Polymorphs I and II share a similar layered structure not exhibited by Polymorph III. All three ambient temperature polymorphs show evidence of varying degrees of dynamic disorder of the terminal phenyl group as shown by solid-state NMR spectroscopy. Furthermore, the carbons alpha to the ether link also undergo different rates of mobility in Polymorphs I and II. This variation in the extent of dynamic disorder results in an alteration in the short-range structure resulting in distinct polymorphs. Polymorph I is the thermodynamically stable form at room temperature as indicated by solution calorimetry and assessment by thermodynamically driven solution mediated phase transition studies. The present study aims to address the types of discriminatory data required to make a clear distinction between physical forms and define, unequivocally, the presence of polymorphism.

Phase II study of sequential hormonal therapy with anastrozole/exemestane in advanced and metastatic breast cancer

Hormonal therapy is the preferred systemic treatment for recurrent or metastatic, post-menopausal hormone-receptor-positive breast cancer. Previous studies have shown that there is no cross-resistance between exemestane and reversible aromatase inhibitors. Exposure to hormonal therapy does not hamper later response to chemotherapy. Patients with locally advanced or metastatic, hormonal receptor positive or unknown, breast cancer were treated with oral anastrozole, until disease progression, followed by oral exemestane until new evidence of disease progression. The primary end point of the study was clinical benefit, defined as the sum of complete responses (CR), partial responses (PR) and > 24 weeks stable disease (SD). In all, 100 patients were enrolled in the study. Anastrozole produced eight CR and 19 PR for an overall response rate of 27% (95% CI: 18.6-36.8%). An additional 46 patients had long-term (> 24 weeks) SD for an overall clinical benefit of 73% (95% CI: 63.2-81.4). Median time to progression (TTP) was 11 months (95% CI: 10-12). A total of 50 patients were evaluated for the second-line treatment: exemestane produced one CR and three PR; 25 patients had SD which lasted > or = 6 months in 18 patients. Median TTP was 5 months. Toxicity of treatment was low. Our study confirms that treatment with sequential hormonal agents can extend the period of time during which endocrine therapy can be used, thereby deferring the decision to use chemotherapy.

Erythrocyte membrane alterations during ageing affect ?--glucuronidase and neutral sialidase in elderly healthy subjects

In this study, a comparison between elderly (>70 years) and young subjects reveals that elder people are subject to a higher oxidative stress, which causes an increase in plasma hydroperoxide levels (18%) and a decrease in antioxidant defenses (25%). Moreover, the marked decrease of the erythrocyte membrane fluidity observed in elderly subjects was likely to affect the behavior of some membrane glycohydrolases. In fact, a significant decrease of beta-d-glucuronidase and neutral sialidase (30 and 50%, respectively) was detected. Activity differences were also observed when erythrocytes were further distinguished according to their biological age. Striking differences between young and elderly subjects were observed for beta-d-glucuronidase and neutral sialidase in young and senescent erythrocytes, respectively. Overall beta-d-glucuronidase decreases with the subjects' age, while neutral sialidase levels are higher in the elderly. This is presumably due to the localization of these enzymes in distinct plasma membrane micro-domains, which are differently peroxidized. A possible role of these enzymes in signaling praecox membrane alterations has also been evidenced.

Penetrating Atherosclerotic Ulcers of the Infrarenal Aorta: Life-threatening Lesions

OBJECTIVES

To analyze the incidence, clinical features, natural history, and treatment of penetrating atherosclerotic ulcers (PAU) of the abdominal aorta.

MATERIAL AND METHODS

From January 2000 to June 2003, an abdominal PAU was diagnosed at our institution in eight patients (seven men, one woman; mean age 70 year). These eight cases were analyzed together with 38 additional cases found in a review of the literature (total 46 cases).

RESULTS

Occurring at an incidence of approximately 1%, abdominal PAU are less common than thoracic PAU. Seventy percent of cases are symptomatic: pain 52.5% (n =21), acute lower limb ischemia due to distal embolism 12.5% (n =5), shock 5% (n =2). Diagnosis is usually made by CT (66%) (n =26) that demonstrates a PAU in 35% (n =16) of cases, a subadventitial pseudoaneurysm in 28% (n =13), and rupture in 37% (n =17). An intramural hematoma (IMH) is observed in 9% (n =4) of cases. There were no cases of aortic dissection in this series. Calcifications of the abdominal aorta were frequent (56%) (n =26); while intra-aortic mural thrombus was found in 24% of cases (n =11), and 46% of patients (n =21) had an associated aneurysm. Twelve patients were treated medically while 34 underwent surgery (one postoperative death).

CONCLUSION

Review of the literature and this series suggests that PAU of the abdominal aorta is a life-threatening lesion, the main risk being rupture. Surgical management is recommended owing to its low morbidity and mortality.

Characterization and metal affinity of Tirofiban, a pharmaceutical compound used in acute coronary syndromes

The crystal and molecular structure of Tirofiban [N-(n-butanesulfonyl)-O-(4-(4-piperidinyl)-butyl)-(S)-tyrosine] is here reported. In the solid state the carboxylic group is in the anionic form while the piperidine molecule appear in the protonated form. By H NMR spectroscopy and potentiometric study three pKa are found: pKa(COOH) = 3.1 (1), pKa(NHPIP) = 11.6(1) and pKa(NHSO2) = 13.8(1). The complexing ability of Tirofiban towards various metal ions (Cu(II), Ni(II), Co(II), Cd(II), Pb(II), Zn(II) and Ca(II)) is also determined by means of potentiometric studies. The prevailing species are [M(TirH)2]2+ where the ligand coordinates the metal ion through carboxylic group, while the piperidine nitrogen is still protonated. The great stability of these complexes may be due to the presence of hydrogen bond interactions, as well as the formation of stacking interactions involving the phenyl ring of the tyrosine residue.

Iron(III) complexing ability of carbohydrate derivatives

A solution study on the coordinative ability of galactaric acid (GalAH(2)), d-glucosamine (GlcN) and d-glucosaminic acid (GlcNAH) toward Fe(3+) ion is reported. UV spectroscopic study provides useful information to identify complex species formation and their stability constants are determined by means of potentiometric measurements. GalAH(2) behaves as chelating ligand through carboxylic oxygen and alpha-hydroxylic oxygen in the protonated or dissociated form depending on pH value. Two complex species [Fe(2)GalA(OH)(4)] and Na[FeGalAH(-2)] .2H(2)O are also isolated in the solid state and characterised through IR spectroscopy. GlcNAH also binds the Fe(3+) ion through carboxylic and hydroxylic groups, while NH(2) group is probably involved in metal coordination up to pH 4. GlcN demonstrates low ligating ability at acidic pH and does not prevent metal hydroxyde precipitation.

[Cardiotoxicity associated with trastuzumab (herceptin). An undesired effect leads towards a model of cardiac insufficiency]

Anticancer chemotherapy continues to advance. One of the new therapeutic orientations is the targeting of receptors which regulate the tumoral activity of the malignant cells. Trastuzumab is the prototype of these new chemotherapeutic agents. It is a monoclonal antibody directed against a tyrosine kinase receptor related to the EGF (Epidermal Growth Factor): the HER receptor. This receptor is also present in myocardial cells. Blockade of this myocardial receptor could cause severe cardiotoxicity about which some information is available but which continues to pose many problems. This data should be known as cardiologists will be consulted before the prescription of Trastuzumab and could also be confronted by these cardiotoxic effects. Precise physiopathological explanations have already been published from experimental studies which show the deleterious effects of the suppression of certain HER receptors on the heart. These studies not only explain all the clinical signs of Trastuzumab's cardiotoxicity but also suggest ways of preventing and treating some of these cases of cardiac failure.

Engineering of quorum-sensing systems for improved production of alkaline protease by Bacillus subtilis

AIM

Engineering of Rap-Phr quorum-sensing systems of Bacillus subtilis and subsequent evaluation of the transcription of the aprE gene, encoding a major extracellular alkaline protease.

METHODS AND RESULTS

Addition of synthetic Phr pentapeptides to the growth medium, or overproduction of pre-Phr peptides, slightly improved the transcription of the aprE gene in B. subtilis. Disruption of certain rap genes similarly improved the transcription of the aprE gene. The production of extracellular proteolytic enzymes was increased when the rapA mutation was combined with a degU32 (Hy) mutation for hyper-secretion.

CONCLUSIONS

Certain Rap-Phr systems of B. subtilis seem to suppress extracellular AprE production. Although this may be an important feature under natural conditions, repression of AprE production by these systems is not desirable under fermentation conditions.

SIGNIFICANCE AND IMPACT OF THE STUDY

Although the levels of aprE transcriptional increase in this study are moderate, engineering of Rap-Phr systems may be used to improve the yield of Bacillus strains that are used for the production of the extracellular protease AprE, or Bacillus strains that use of the aprE promoter for the production of a heterologous protein.

COGNITIVE AND AFFECTIVE DISORDERS IN THE ELDERLY: A NEUROENDOCRINE STUDY

Both in physiological and pathological brain aging, cognitive and affective disorders usually keep up with significant morphological and metabolic changes of brain areas possibly involved in the control of mood, learning and memory, as well as in the modulation of the hypothalamo-pituitary-adrenal (HPA) axis. The aim of this work was to study the circadian rhythm of serum cortisol and dehydroepiandrosterone (DHEAS) in 25 old demented patients and 10 old unipolar depressed patients, compared with 21 old and 13 young controls. The circadian profile of serum cortisol was clearly flattened in elderly subjects,both healthy and demented, in comparison to young controls, with significantly higher cortisol levels at nighttime. The occurrence of minor depression was associated with a further increase of the cortisol mean levels in old demented subjects, but not in the healthy ones. The trend towards the increase of the nocturnal cortisol levels was also evident in old subjects with major depression. The decline of DHEAS secretory pattern was clearly age related,being additive factors to both dementia and major depression. No significant influence of minor depression on DHEAS secretion was found. The cortisol/DHEAS molar ratio,considered as a good index of the brain steroidal milieu, progressively increased with aging and exhibited a further increase related to the occurrence of senile dementia or minor depressive symptoms. The value of the same ratio was higher in elderly subjects with major depression, than in age-matched healthy controls. In conclusion, the occurrence of major depression or even only of depressive symptoms seems to amplify the changes of the adrenal steroidal secretory pattern, already present in physiological aging.

[Impact of biochemisty on the duration of treatment for pulmonary embolus]

Can the biochemical evidence for "new thrombophilic factors" influence the duration of AVK treatment following the occurrence of a first pulmonary embolus? Certainly for the classic but very rare antithrombin defects as well as for the existence of circulating anticoagulant. Possibly for protein C and S defects. On the other hand, the existence of a heterozygotic "Leiden" mutation of factor V, or factor II, and an increase of factors VIII, IX, or XI, do not at present warrant a change in AVK prescription. In effect, in the case where the existence of a thrombogenic state implies a prolongation of AVK treatment with its significant potential complications, it is indispensable that the risk/benefit ratio is well founded, which is not the case for these "new" thrombophilic states. The coexistence of several of these new biochemical anomalies (for example the association of a factor V and factor II mutation) probably represents an excess risk of thrombosis, but in this situation the reasoning remains the same. On the other hand, faced with a confirmed recurrence, the studies in the literature tell us that very long term treatment should be debated independently from the biochemical results. It is conceivable that there are biochemical anomalies (sometimes quite frequent which should be viewed as "normal variants") which, although they have great significance for improving the understanding of venous thrombo-embolic disease, do not at present warrant a change in our therapeutic protocols. Another facet of the problem concerns the use of D-dimers following the first months of AVK treatment in order to possibly distinguish patients at low risk of recurrence. The first results of this approach are interesting, but require confirmation before they can be used in practice.

An escalating dose finding study of liposomal doxorubicin and vinorelbine for the treatment of refractory or resistant epithelial ovarian cancer

BACKGROUND

The aim of this study was to determine the maximum tolerated dose (MTD) of liposomal doxorubicin (LD)-vinorelbine (V) in patients with refractory or resistant ovarian cancer.

PATIENTS AND METHODS

Thirty patients were eligible. Seven levels were studied [LD 25-V20 (three patients enrolled); LD 30-V20 (three); LD 35-V20 (three); LD 20-V25 (three); LD 25-V25 (three); LD 30-V25 (10); LD 35-V25 (five)]. LD was given on day 1, while V was given on days 1 and 8 every 21 days. Cohorts of three patients were enrolled at each level, and another three patients were planned, if one dose-limiting toxicity (DLT) was registered.

RESULTS

DLT was observed in four patients: two febrile neutropenia, one grade 4 thrombocytopenia and one grade 3 palmar-plantar erythrodysesthesia (PPE) at level 7 (LD 35-V25). Thus, liposomal doxorubicin 30 mg/m(2) plus vinorelbine 25 mg/m(2) was the MTD. The most frequent toxicity was neutropenia. Fifteen patients (50%) experienced grade 3 neutropenia and 10 (33.3%) grade 4 neutropenia. Non-hematological toxicity was mild. Mucositis and PPE were the most frequent toxicities, but in most cases were grade 1. Out of 29 assessable patients, six (20.7%; 95% confidence interval 10%-39%) experienced an objective response, with one complete response.

CONCLUSIONS

In patients with refractory or resistant ovarian cancer, the recommended doses for the combination studied are liposomal doxorubicin 30 mg/m(2) (day 1) plus vinorelbine 25 mg/m(2) (day 1 and 8). Neutropenia is the most frequent toxicity, while non-hematological toxicity is mild. Substantial activity was recorded and a phase II study is justified.

High-dose epirubicin, preceded by dexrazoxane, given in combination with paclitaxel plus filgrastim provides an effective mobilizing regimen to support three courses of high-dose dense chemotherapy in patients with high-risk stage II-IIIA breast cancer

SUMMARY

We verified the possibility of collecting large amounts of peripheral blood stem cells (PBSCs) to support three courses of adjuvant high-dose dense chemotherapy (HDDC) with high-dose epirubicin, preceded by dexrazoxane, and high-dose paclitaxel, in patients with high-risk breast cancer (>/=9 positive nodes). The mobilizing regimen consisted of high-dose epirubicin 150 mg/m(2), preceded by dexrazoxane 1000 mg/m(2) (day 1), given in combination with paclitaxel 175 mg/m(2) (day 2), plus filgrastim. Of the 25 patients enrolled, one went off study due to a severe hypersensitivity reaction to paclitaxel, another did not undergo leukapheresis due to fever persistent after hematological recovery, while in 23 patients an adequate number of PBSCs was collected by a single leukapheresis. The median number of CD34+, CD34+/CD33-, and CD34+/CD38- cells collected per patient was 17 x 10(6)/kg, 13.4 x 10(6)/kg, and 1.5 x 10(6)/kg, respectively. Neutropenia was the only grade 4 toxicity and lasted a median of 3 days. High-dose epirubicin, preceded by dexrazoxane for the first time used in mobilizing regimen, and paclitaxel plus filgrastim are effective in releasing large amounts of PBSCs, which can then be safely employed to support multiple courses of HDDC.