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.

Synthesis and characterization of new β-diketo derivatives with iron chelating ability

Here we report the synthesis, the characterization and a theoretical study on new glycosylated phenyl substituted beta-diketones; two classes of compounds are obtained according to the condensation reaction: central and side derivatives. Their iron(III) chelating ability is tested by means of UV-visible (UV-vis), potentiometric and NMR techniques. The conformation of central derivatives does not allow any metal chelation, while side derivatives bind iron(III) through the beta-dioxo moiety. The glycosyl moiety does not interact with metal ion but it helps to stabilize metal/ligand (1/3) complexes by means of hydrophylic interactions. The pK(a) of the ligands and the stability constants of their Fe(III) complexes are evaluated by means of UV-vis spectroscopy and potentiometry. A comparison with other iron-chelating agents, on the basis of lipophilicity and the pFe(III), is finally reported.

[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.

PcF protein from Phytophthora cactorum and its recombinant homologue elicit phenylalanine ammonia lyase activation in tomato

The phytotoxic protein PcF (Phytophthora cactorum-Fragaria) is a 5.6-kDa cysteine-rich, hydroxyproline-containing protein that is secreted in limited amounts by P. cactorum, an oomycete pathogen of tomato, strawberry and other relevant crop plants. Although we have shown that pure PcF triggers plant reactivity, its mechanism of action is not yet understood. Here we show that PcF, like other known fungal protein elicitors involved in pathogen-plant interaction, stimulates the activity of the defense enzyme phenylalanine ammonia lyase (EC 4.3.1.5) in tomato seedlings. Recognizing that a key step in understanding the mechanism of action of PcF at a molecular level is knowledge of its three-dimensional structure, we overexpressed this protein extracellularly in Pichia pastoris. The preliminary structural and functional characterization of a recombinant PcF homologue, N4-rPcF, is reported. Interestingly, although N4-rPcF is devoid of proline hydroxylation and has four additional amino acid residues attached to its N terminus, its secondary structure and biological activity are indistinguishable from wild-type PcF.

Co-ordination of transition metal ions by galactaric acid: a potentiometric and spectroscopic study

A solution study on the ability of galactaric acid [GalaH(2), HOOC(CH)(4)COOH] in the complexation of biological metal ions such as Co(II) and Ni(II) and toxic metal ions such as Cd(II), Pb(II) and Hg(II), is reported. The stability constants of the complex species are determined by means of potentiometric measurements. Galactaric acid behaves as chelate ligand through carboxylic oxygen and alpha-hydroxy group towards Co(II) and Ni(II), while in the Pb(II) and Cd(II) containing system it co-ordinates the metal ion with carboxylic oxygen and two alcoholic hydroxy groups. The prevailing species at acidic or neutral pH is [MGala] which is also isolated in the solid state and characterized by means of IR spectroscopy. On increasing pH, the [MGalaH(-1)](-) species is also formed where the co-ordinated OH group undergoes deprotonation in all metal ion complexes except those with Hg(II), where the co-ordination of hydroxide ion is suggested as the precipitation of the metal hydroxide occurs at pH 7.

Ab-interno trabeculo-canalectomy: surgical approach and histological examination

PURPOSE

To evaluate, on eye bank eyes, a new surgical approach aimed at removing a quadrant of the trabecular meshwork (TM), with an ab interno approach.

METHODS

Gonioscopically controlled ab interno removal of the TM was done with a subretinal forcep on six human bank eyes. Serial histological sections were obtained from the treated and untreated part of each globe to assess the effect of the technique on intraocular tissues.

RESULTS

Under the gonioscope, the TM was easily removed in strings of varying length. Histological examination showed, unexpectedly, that this resulted in a well-defined deep furrow in the middle of the trabecular region involving both the TM and the inner wall of Schlemm's canal. The operation created a direct communication between the anterior chamber and Schlemm's canal lumen without any evident damage to the outer canal wall and adjacent ocular structures such as the iris base and corneal endothelium.

CONCLUSIONS

Our small series on human bank eyes showed that the procedure involves both the TM and the inner wall of Schlemm's canal and is therefore called ab interno trabeculocanalectomy (AITC). The intraoperative findings and the histological evidence are encouraging, and suggest that the procecedure could have potential clinical application.

Effects of repeated exposures to xenon on rat adrenal cortex ultrastructure

Xenon has many properties of the ideal anaesthetic and it has been proposed to replace classic volatile anaesthetics. Although some studies demonstrated that xenon does not induce gross morphological changes in major organs, little is known on its possible ultrastructural effects. The present study investigates the subcellular effects of repeated exposures to 70% xenon on rat adrenal cortex in comparison with N2O. Animals were divided into four groups: xenon-exposed, N2O-exposed, sham-exposed and controls. Exposed rats were placed into a sealed cage to breathe the respective gas mixture for 2.5 h/day for a week. Specimens of adrenal cortex for electron microscopy and blood samples for determination of corticosterone plasma levels were taken at the end of the last exposure or one week after the last exposure (recovery). Adrenal cortex from N2O- and sham-exposed rats mainly showed dilation of endoplasmic reticulum, whereas xenon-exposed rats also exhibited several cells with lipid droplets appearing subdivided into smaller droplets, irregular in shape and size. In all experimental groups, corticosterone plasma levels increased in comparison to controls. Both ultrastructural and hormonal changes were not detected anymore after one week from the last exposure. These findings indicate that xenon is able to induce subcellular changes in rat adrenal cortex, mainly at the level of lipid structures. The transient changes induced by xenon suggest that this gas can be regarded as a safer anaesthetic.

Binding ability of sialic acid towards biological and toxic metal ions. NMR, potentiometric and spectroscopic study

The binary complexes of 5-amino-3,5-dideoxy-D-glycero-D-galactononulosic acid (NANA), commonly called N-acetyl neuraminic acid, formed with biological metal ions such as Co(II) and Cu(II) and toxic metal ions such as Cd(II) and Pb(II) were investigated in aqueous solution by means of potentiometry, UV and NMR spectroscopy. The corresponding ternary systems with 2,2'-bipyridine were studied in aqueous solution by potentiometry and UV spectroscopy. NANA co-ordinates all metal ions, in both binary and ternary systems through the carboxylic group (protonated or deprotonated according to pH), pyranosidic ring oxygen and glycerol chain alcoholic hydroxy groups. The prevailing species in the pH range 2-7 are of [M(NANA)(2)] type, and their stability constants are greater than those of simple carboxylate complexes. Above pH 7, the species [M(NANA)(2)OH](-) are also formed, but they do not prevent the precipitation of metal hydroxides. This work provides information on the solution state chemistry of NANA in the presence of bivalent metal ions; its great affinity for the toxic metals Cd(II) and Pb(II), near physiological conditions, and the relatively high stability of the complex species found may also account for the mechanism of toxicity.

[The best of 2001. Thrombosis]

Although it is impossible to recall all the new developments of the year 2001 regarding thrombosis, we have selected certain results: several, with although "negative" results, are highly interesting because they contradict preliminary studies which could have predicted therapeutic perspectives that would considerably alter the management of a common and serious illness. In this sense, they remind us that the large randomised studies (RCT) remain the necessary and indispensable tool for validating a large scale therapy: others, because they come within the logic of certain earlier results, and in this sense it is good for a clinician to see that a certain logic still exists in cardiology; others again, because they define a certainly real benefit, but whose limits of applicability could sometimes escape clinicians.

Thyroid function in physiological aging and in centenarians: possible relationships with some nutritional markers

Changes in thyroid function are often described in elderly subjects; however, their pathophysiologic significance and the possible contributory role of both malnutrition and nonthyroidal illness are still debated. The aim of this cross-sectional study was to investigate thyroid function in relationship to some markers of the nutritional status in a group of healthy old subjects and in some centenarians living in nursing homes. Patients included 24 clinically healthy elderly women (age, 71 to 93 years), 24 clinically healthy centenarian women (age, 100 to 106 years), and 20 healthy young subjects (age, 22 to 33 years). Blood samples were drawn from each subject for the evaluation of thyroid-stimulating hormone (TSH), free triiodothyronine (FT(3)), free thyroxine (FT(4),) reverseT(3) (rT3), autoantibodies against thyroglobulin (AbTg) and against thyroid peroxidase (AbTPO), and for the main humoral nutritional markers. TSH and thyroid hormones were assayed by fluoroimmunometric method; rT3 and thyroid autoantibodies by radioimmunoassay (RIA) and enzyme chemiluminescent immunometric assay, respectively. The mean values of TSH, FT(3) and FT(4) fell within the normal range in both groups. However, by comparison to old controls, in centenarian subjects, TSH levels were significantly lower, whereas rT(3) concentrations were slightly, but significantly, increased. Autoantibodies positivity was found in 4.16% of centenarians and in 10.4% and 13.6% of old and young controls. Thus, the incidence of thyroid autoantibodies was lower in centenarians than in old controls. Except for transferrin, lower than the normal range in centenarians, all of the other nutritional markers evaluated fell within the laboratory range of normality. Total cholesterol levels were significantly reduced in centenarians by comparison to old controls. Our results showed an age-related decline of the TSH levels and a significant increase of the rT(3) concentrations in centenarians by comparison to old controls. These findings may be related to an age-dependent reduction of the 5'-deiodinase activity rather than to important changes of nutritional markers.

Correlation between Bacillus subtilis scoC phenotype and gene expression determined using microarrays for transcriptome analysis

The availability of the complete sequence of the Bacillus subtilis chromosome (F. Kunst et al., Nature 390:249-256, 1997) makes possible the construction of genome-wide DNA arrays and the study of this organism on a global scale. Because we have a long-standing interest in the effects of scoC on late-stage developmental phenomena as they relate to aprE expression, we studied the genome-wide effects of a scoC null mutant with the goal of furthering the understanding of the role of scoC in growth and developmental processes. In the present work we compared the expression patterns of isogenic B. subtilis strains, one of which carries a null mutation in the scoC locus (scoC4). The results obtained indicate that scoC regulates, either directly or indirectly, the expression of at least 560 genes in the B. subtilis genome. ScoC appeared to repress as well as activate gene expression. Changes in expression were observed in genes encoding transport and binding proteins, those involved in amino acid, carbohydrate, and nucleotide and/or nucleoside metabolism, and those associated with motility, sporulation, and adaptation to atypical conditions. Changes in gene expression were also observed for transcriptional regulators, along with sigma factors, regulatory phosphatases and kinases, and members of sensor regulator systems. In this report, we discuss some of the phenotypes associated with the scoC mutant in light of the transcriptome changes observed.

[The hypocaloric balanced diet therapy and the supplementation with antioxidant and omega-3: what are the effects on the oxidative balance and erythrocytes membrane fluidity status?]

BACKGROUND

To investigate the effects of a hypocaloric balanced diet therapy and a supplementation with antioxidant and omega-3 polyunsaturated fatty acids on the oxidative balance and erythrocytes membrane fluidity status.

METHODS

A randomised, double-blind, placebo-controlled study of the association between a hypocaloric balanced diet therapy and a supplementation with antioxidant and omega-3 was done on 40 women with 25 < BMI < 33. The inclusion criteria were the following: absence of dismetabolic pathologies, of previous hypocaloric diet therapy and/or supplementation and of hormonal treatments. Each subjects consumed a balanced diet with a daily caloric intake equal to: Kcal of basal metabolism (determined by indirect calorimetry) x LAF (1.64) 800 Kcal. At the start and after two months of treatment, the blood chemistry and anthropometrics parameters, the plasmatic reactive oxygen species (ROS) and antioxidant defence levels and erythrocyte membrane fluidity status were measured.

RESULTS

The preliminary results of this study show that the weight loss, found in both groups investigated, determines a significant decrease of ROS. Furthermore, the association of the hypocaloric diet with antioxidant and omega-3 polyunsaturated fatty acids caused a significant increase of both plasmatic antioxidant defences and erythrocytes membrane fluidity status.

CONCLUSIONS

The correlations found between the above parameters and the blood chemistry and anthropometrics variables suggest that the supplementation with antioxidant and omega-3 polyunsaturated fatty acids could ameliorate the effects of hypocaloric diet on the obesity treatment and may give some clinical benefit through the decrease of the values of atherosclerosis risk factors.

[Dietary restriction and oral administration of antioxidant and omega-3: what are the effects on the clinical variables in a group of obese women?]

BACKGROUND

Obesity is now recognized as a major risk factor for many pathologies. The state of obesity is associated with an increase in reactive oxygen species; persistent overconsumption of calories in the obese may be exposing them to excessive damage besides maintaining the state of obesity. It is possible that dietary modification and association with assumption of antioxidant and omega-3 oral integration contributes to a reduction in reactive oxygen species generation and a corresponding reduction in indexes of oxidative damage, including lipid peroxidation.

METHODS

Given this back-ground, the pro/anti-oxidant balance, biochemical parameters and the body composition were studied in two groups of obese women: a first group of 10 obese women were studied before and after eight weeks of dietary restriction and a second group of 12 obese women were studied before and after eight weeks of dietary restriction and oral administration of antioxidant and omega-3.

RESULTS

In summary, as regards the preliminary results of clinical outcome parameters, interestingly enough the glycemic levels fall markedly in association with both dietary restriction and oral integration with antioxidant and omega-3. Another important finding of this study is that of calcium levels and phase angle (measured by impedenzometry) increase in the group treated with dietary restriction and oral administration of antioxidant and omega-3.

CONCLUSIONS

Studies that aimed to explore whether oxidative status predicts clinical outcome would provide important details on the putative link between oxidative status and state of obesity.

Adipose tissue and cytokines

Adipose tissue is not simply a storage depot for excess energy intake, it is also able to produce and release several substances with local (autocrine) and systemic (endocrine) actions. An up-to-date review of our knowledge in this area is given here. Several of the compounds deriving from adipose tissue have been shown to play a role in obesity-related health complications. The production of cytokines, such as Tumor Necrosis Factor-alpha (TNF-alpha), IL-6, and leptin, is implicated in the development of several disorders. Insulin resistance is one of the most clinically significant.

The X-ray structure of a recombinant major urinary protein at 1.75 A resolution. A comparative study of X-ray and NMR-derived structures

Major urinary proteins belong to the lipocalin family and are present in the urine of rodents as an ensemble of isoforms with pheromonal activity. The crystal structure of a recombinant mouse MUP (rMUP) was solved by the molecular-replacement technique and refined to an R factor and R(free) of 20 and 26.5%, respectively, at 1.75 A resolution. The structure was compared with an NMR model and with a crystallographic structure of the wild-type form of the protein. The crystal structures determined in different space groups present significantly smaller conformational differences amongst themselves than in comparison with NMR models. Some, but not all, of the conformational differences between the crystal and solution structures can be explained by the influence of crystallographic contacts. Most of the differences between the NMR and X-ray structures were found in the N-terminus and loop regions. A number of side chains lining the hydrophobic pocket of the molecule are more tightly packed in the NMR structure than in the crystallographic model. Surprisingly, clear and continuous electron density for a ligand was observed inside the hydrophobic pocket of this recombinant protein. Conformation of the ligand modelled inside the density is coherent with the results of recent NMR experiments.

[Membrane fluidity and obesity: the correct food approach]

Modifications in dietary fat profile have shown to affect body weight gain and adiposity. This may occur through the changes of cell membrane fluidity, in particular of the peripheral muscle tissue. The decreased availability of diet polyunsaturated fatty acids (in particular of the to-3 series), that are able to induce membrane fluidification, together with an excessive intake of both saturated fatty acids and cholesterol, that on the contrary are able to rigidify the same membranes, promoter both a progressive immobilization of membrane proteins and a consequent decrease in their functional rate of liver lipoproteins VLDL, enriched in saturated fats and cholesterol. This lipoprotein increase promotes both the fat deposition in the adipose tissues and a further increase in the muscle membrane rigidity that is followed by a further enhancement in the peripheral resistance to insulin. A diert rich both in polyunsaturated fatty acids and antioxidants (vitamin and oligoelements), and in essential amino acids together with a preferential choice of complex carbohydrates (amylose, amylopectine, etc) in comparison to simple sugars (glucose, fructose, saccharose, lactose, etc) may significantly contribute to the maintenance of the correct degree of membrane fluidity and, as a consequence, to the physiologically correct body weight.

Age-related changes of the adrenal secretory pattern: possible role in pathological brain aging

The biosynthetic dissociation of the adrenocortical secretion occurring with age may have a pathogenetic role in the pathophysiology of brain aging. We studied cortisol and DHEAS secretion in healthy old and young subjects, in senile dementia, in major depression of elderly subjects and in healthy centenarians. A clear age-related decline of DHEAS secretion was well evident in healthy centenarians, and a further decrease in DHEAS concentration was found in old depressed patients and moreover in the demented ones, by comparison with age-matched controls. The circadian profile of serum cortisol was clearly flattened in old subjects, due to the selective increase in the cortisol nocturnal levels, particularly evident in demented subjects; on the other hand, the morning serum cortisol levels were not significantly different among centenarians, young and old controls. The molar ratio between cortisol and DHEAS showed a significant age-related increase; the occurrence of senile dementia and of major depression played an additive role, by comparison to physiological aging. The qualitative and quantitative modifications of the adrenocortical secretion occurring with aging seem mainly dependent on age itself, but the occurrence of pathological conditions may amplify these changes. Since cortisol and DHEAS play opposite effects on the central nervous system, the evaluation of the ratio between cortisol and DHEAS seems to be a good marker of the neuroendocrine features in old subjects.

Sugar complexes with metal(2+) ions: thermodynamic parameters of associations of Ca(2+), Mg(2+) and Zn(2+) with galactaric acid

A solution study on the complex ability of galactaric acid (GalaH(2)) for complexation with Ca(2+), Mg(2+) and Zn(2+) ions is reported. The stability constants of the complex species are determined by means of potentiometric measurements. From the dependence of stability constants on temperature, the DeltaH degrees and DeltaS degrees values are also determined. The formation of the complex species is an endothermic process and DeltaH degrees and DeltaS degrees values suggest a chelate coordination mode of galactaric acid involving carboxylic oxygen and alpha-hydroxylic group. The prevailing species at acidic or neutral pH is [MGala] (M=Ca(2+), Mg(2+), Zn(2+)) which is also isolated in the solid state and characterised by means of IR spectroscopy. On increasing pH, the [MGalaH(-1)](-) species is also formed, where the coordinated OH group undergoes deprotonation.

Botulinum toxin type a neuromuscular blockade in the treatment of equinus foot deformity in cerebral palsy: a multicenter, open-label clinical trial

BACKGROUND

Focal spasticity of the gastrocnemius-soleus muscles causes equinus gait in children with cerebral palsy (CP). Botulinum toxin type A (BTX-A), a neuromuscular blocking agent, reduces muscle tone/overactivity in dystonia, stroke, and CP.

OBJECTIVE

A prospective, open-label, multicenter clinical trial evaluated the long-term safety and efficacy of repeated intramuscular injections of BTX-A on equinus gait in CP children.

METHODS

Nine centers enrolled 207 children. BTX-A injections (4 U/Kg) were given approximately every 3 months (maximum dose 200 U per treatment). Outcome measures included a Physician Rating Scale of gait, ankle range of motion measurements, and the incidence and profile of adverse events.

RESULTS

One hundred fifty-five (75%) of 207 children completed at least 1 year with a total of 302 patient years of BTX-A treatment. The mean duration of BTX-A exposure was 1.46 years per patient. Dynamic gait pattern on the Physician Rating Scale improved in 46% of patients (86/185) at first follow-up. The response was maintained in 41% to 58% of patients for 2 years. Both gait pattern and ankle position improved at every visit. The most common treatment-related adverse events included increased stumbling, leg cramps, leg weakness, and calf atrophy in 1% to 11% of patients. No treatment-related serious adverse events were reported. Only 6% (7/117) of patients with pre- and postantibody samples had both detectable antibodies and a subsequent treatment failure.

CONCLUSION

BTX-A proved both safe and effective in the chronic management of focal muscle spasticity in children with equinus gait.

[Duration of antivitamin K therapy in venous thromboembolic disease. Certainties and uncertainties]

The necessity of anticoagulant treatment after a pulmonary embolus or a deep venous thrombosis has been demonstrated. The modalities of this treatment have been well established, especially the usefulness of initial heparin therapy followed by a period of antivitamin K treatment with an "ideal target INR" between 2 and 3. One of the last questions in this therapeutic protocol is the duration of antivitamin K treatment. The choice of duration of treatment must be made on numerous criteria. It is necessary to distinguish the circumstances of the occurrence of the DVT or the PE and the context. It is thus possible for less than 3 months treatment in secondary venous thrombo-embolic disease, which occurs in precise, recognised circumstances for which the cause will have been controlled. Otherwise, in so-called idiopathic venous thrombo-embolic disease, which is distinguished by a higher prevalence of recurrences, it is known that long-term antivitamin K treatment is effective for the thrombo-embolic recurrences but at the price of a risk of haemorrhage. Finally thrombo-embolic recurrences also benefit from a long treatment. These circumstances of occurrence are thus important in order to decide the choice of treatment duration. But, in our opinion, the compliance to antivitamin K treatment remains the primary criterion to consider. The dilemma facing the prescriber is to evaluate the risk-benefit ratio of each patient, asking especially if the antivitamin K treatment surveillance of a particular patient will be done as well as in the randomised studies. For the future, long-term antivitamin K does not perhaps represent the only therapeutic option. The results of studies evaluating the durations of long-term treatment with less intense levels of anticoagulation (INR < 2) as well as therapeutic alternatives to antivitamin K (antiaggregants or other antithrombins) are awaited.

[When is antivitamin K therapy indicated in the stable coronary patient?]

In the cardiac patient, there are clinical situations where antivitamin K is indicated more by the co-existing pathological associations or by a particular thrombogenic situation than by the cardiac disease itself. The presence of an embologenic abnormal rhythm, an apical thrombus or a large anterior akinesis are recognised as situations where antivitamin K must be discussed and, except for absolute contraindication, initiated. The studies undertaken for several decades are highly instructive and their contributions are considerable in the different questions which could be asked regarding the efficacy of antivitamin K. In particular they have the merit of signalling the correct directions to take and the errors to avoid. Concerning the evolution of cardiac disease, it must be admitted that the very good results of antivitamin K treatment alone at high dose are to be balanced against their haemorrhagic risk. The studies testing the association of low-dose aspirin with moderate-dose antivitamin K (INR 2 to 2.5) are to date very promising. The evaluation of the understanding of the treatment by patient education remains a major stage when initiating antivitamin K treatment in the cardiac patient.

[Venous thromboembolism and cancer]

Malignant disease predisposes to deep venous thrombosis (DVT) or pulmonary embolism (PE) in several ways. One classical situation is that of DVT or PE with no apparent cause which may be the first sign of an occult cancer. In this domain, although the epidemiological data is well known, it is important to recognise the limitations of "blind" investigations. Another situation is more common. The patients have a diagnosed malignancy and thromboembolic disease is the main extra-cancer complication. The approach to this problem is changing, both in primary prevention where many trials have already reported encouraging results, and in the treatment after the event where classical therapeutic protocols are not always well adapted. Ancestral fears of the prescription of anticoagulants in cancer patients must cede to a more objective benefit/risk analysis which seems to be very favourable in some situations. Moreover, some publications have demonstrated a chance finding of a possible anticancer effect of antithrombotic agents.