Neurotransmitter and hormonal background of hostility in anorexia nervosa

Marked hostility toward relatives, therapists and friends is very frequently observed in anorexia nervosa (AN) as expression of outward-directed aggressiveness which interferes with the therapeutic programs of the patients. With the purpose to investigate this aspect of the disorder and its biological background, we studied in anorexics some neurotransmitter-hormonal secretions which are known to modulate aggressivity-hostility by measuring plasma concentrations of total (TT) and free testosterone (FT), total estrogens (TE), the TT/E and FT/TE ratios, and the serotonergic function by measuring basal prolactin (PRL) levels and responses to stimulation with the specific serotonin (5-HT)-releasing agent D-fenfluramine (D-Fen). In 13 women with AN, 5 of the restricted (AN-R) and 8 of the bingeing/purging type (AN-BP) in an active phase of the disease, and in 13 healthy controls matched for sex and age, we measured hostility by the SCL-90 scale (subscale items 11, 24, 63, 67, 74, 81). Basal TT, FT, TE, TT/TE, FT/TE, PRL values and PRL responses to D-Fen and to saline administration were measured radioimmunologically in AN patients and controls. Hostility was significantly higher in AN patients than in controls, TT, FT and TE concentrations were significantly lower in AN patients than in controls, TT/TE ratio was significantly higher in AN patients than in controls, and FT/TE ratio was not different in the two groups. In AN patients and controls, hostility correlated positively with TT and FT values. Basal PRL values and responses to D-Fen administration were significantly lower in anorexics than in controls, but they did not correlate with the degree of hostility in either patients or controls. In conclusion, hostility is higher than normal in anorexics, and its severity seems to be linked to the secretion of FT and not to the alterations in the 5-HT function.

[Food intake and nutritional status in a group of healthy elderly residing in a nursing home]

BACKGROUND

Aging is accompanied by a variety of economic, psychologic, and social changes that can compromise the nutritional status. Nutrition is an important aspect of healthful behaviour and a major component of general wellbeing of individuals throughout their life cycle. Nutritional intake appears to be an important factor contributing to aging. So, the purpose of this project was to evaluate diet and nutritional status.

METHODS

Fifty-one healthy elderly subjects aged 70 years and older (31 F and 20 M), residing in a nursing home have been studied. Nutrient intake was assessed using 24-hour recalls; nutritional status was assessed using anthropometric measurements. The nutrient intakes for individuals were compared with the Italian Recommended Dietary Allowances (RDAs).

RESULTS

Mean energy intake was 1,625 kcal; the average percentages of carbohydrate, protein, and fat were 54%, 16%, and 30%, respectively. The mean vitamin and mineral intake for participants met the RDAs except for calcium and selenium intakes. The mean fibre intake was low. The analysis of food products intake indicated that the above mentioned inadequacy in nutrient intake was the result of low consumption of milk and milk products containing calcium and a low consumption of integral foods or fruits containing fibre.

CONCLUSIONS

The significance of sound nutrition education and the adverse impact of consumer misinformation about the benefits of these food choices becomes clear with the recognition that nutritional status influences the rate of physiologic and functional declines with age. This approach will require new efforts in consumer education sensitive to the needs and beliefs of older people.

In vivo and in vitro percutaneous absorption of [(14)C]di-N-butylphthalate in rat

This study evaluated the toxicokinetics of [(14)C]di-n-butylphthalate ([(14)C]DBP) after an intravenous administration (1 and 10 mg/kg, in Cremophor) or a topical application (10 microl/cm(2); 10 cm(2), neat) in haired male Sprague-Dawley rats. Additional in vivo and in vitro percutaneous penetration studies of [(14)C]DBP were conducted on male and female haired rats and male hairless rats. After intravenous administration, unchanged DBP disappeared rapidly from the plasma, following a two-exponential function (T1/2beta = 5-7 min). The peak levels of monobutylphthalate (MBP) and its glucuronide conjugate (MBP-Gluc) occurred 1 to 2 and 20 to 30 min after administration, respectively. These metabolites were intensively and rapidly excreted in urine (57% of the dose). However, about 35% of the dose recovered in urine was primarily excreted in bile (mainly as MBP-Gluc) and underwent hepatobiliary recycling. Unchanged DBP was barely detectable in excreta. DBP rapidly penetrated the skin, which constituted a reservoir. The absorption flux determined for 0.5 to 8 and 8 to 48 h of exposure were 43 and 156 microg/cm(2)/h, respectively. The higher flux may be due to radial diffusion of DBP in the stratum and/or epidermis. The in vivo and in vitro experiments revealed that DBP was intensively metabolized into the skin. In vivo percutaneous absorption flux was very similar in male and female haired rats. In contrast, the percutaneous absorption determined in vivo and in vitro was higher in hairless than in haired male rats. Absorption flux was accurately estimated from urinary excretion rate of MBP or MBP-Gluc.

Toxicokinetics and metabolism of 1,2-diethylbenzene in male Sprague Dawley rats--part 2: evidence for in vitro and in vivo stereoselectivity of 1,2-diethylbenzene metabolism

In a previous study, it was shown that the neurotoxic compound 1,2-diethylbenzene (1,2-DEB) is mainly hydroxylated in the alkyl chain to give 1-(2'-ethylphenyl)ethanol (1,2-EPE) and excreted in urine of rats as two glucuronide compounds (GA1 and GA2). Some findings have suggested that the two enantiomers of 1,2-EPE are formed in vivo. In the present study, a chiral high-performance liquid chromatography method was developed to separate the two enantiomers of 1,2-EPE from a synthesized racemic mixture. Absolute configuration of both enantiomers was determined after esterification with (R)-(+)-alpha-methoxy-alpha-(trifluoromethyl)phenylacetic acid and analysis of their (1)H NMR spectra in CCl(4) added with Eu (fod)(3). The two main urinary metabolites, GA1 and GA2, from [(14)C]1,2-DEB-treated Sprague-Dawley rats (80 mg/kg, i.p.) were identified, after hydrolysis with beta-glucuronidase from Escherichia coli, as (R) and (S) glucuronide conjugates of 1,2-EPE, respectively. In vitro hydroxylation of 1,2-DEB and glucuroconjugation of 1,2-EPE were under stereoselective control in S9 fraction or microsomes from male Sprague-Dawley rat liver. The V(max) and K(m) constants for (R)1,2-EPE enantiomer formation determined in S9 fraction were greater than those for the (S) enantiomer. In the plasma of bile duct-cannulated rats, the ratio was 1.2 +/- 0.02 over the 1- to 4-h period after oral administration of [(14)C]1,2-DEB (100 mg/kg). In contrast, the glucuroconjugation rate of (S)1,2-DEB enantiomer was 4 times that of (R)1,2-EPE glucuroconjugation. A similar ratio of (R) to (S)1,2-EPE glucuronide conjugates was obtained in the plasma of bile duct-cannulated rats.

Determining the binding capability of the mouse major urinary proteins using 2-naphthol as a fluorescent probe

The mouse major urinary proteins (MUPs) are an ensemble of isoforms secreted by adult male mice and involved in sexual olfactory communication. MUPs belong to the lipocalin superfamily, whose conserved structure is a beta-barrel made of eight antiparallel beta-strands forming a hydrophobic pocket that accommodates small organic molecules. A detailed knowledge of the molecular mechanism associated to the binding of those molecules can guide protein engineering to devise mutated proteins where the ligand specificity, binding affinity, and release rate can be modulated. Proteins with such peculiar properties may have interesting biotechnological applications for pest control, as well as in food and cosmetic industries. In this work, we demonstrate that the fluorescent molecule 2-naphthol binds to the natural ligand's binding site of MUPs with high affinity. In addition, we show that 2-naphthol binds to MUPs in its protonated form, that its fluorescence is blue-shifted, and the quantum yield is increased, thus confirming the high hydrophobicity of the protein pocket and the absence of proton acceptors inside the binding site. At large the results presented, besides demonstrating that the use of 2-naphthol provides a convenient and quick method for testing MUPs binding activity and to ascertain the quality of the protein preparation, suggest that MUPs can represent an interesting system for studying the photophysical characteristics of fluorescent molecules in a highly hydrophobic environment.

Overproduction of IFN-gamma and TNF-alpha from natural killer (NK) cells is associated with abnormal NK reactivity and cognitive derangement in Alzheimer's disease

Alterations of natural killer (NK) function can be involved in the neuroimmune mechanism of neurodegeneration in dementia of the Alzheimer's type (DAT). NK cell cytotoxicity (NKCC) and the generation and release of IFN-gamma and TNF-alpha (spontaneous and modulated by IL-2) from pure NK cells (CD 16+, CD 56+, CD 3-) were studied together with circulating IFN-gamma and TNF-alpha levels and cognitive function in 22 old patients with DAT and 15 healthy old subjects. Higher (p < 0.001) IL-2 modulated NKCC (with IL-2 50 U/mL and 100 U/mL) was demonstrated in DAT patients (+35% and +99% from baseline) than in healthy subjects (+6% and +76% from baseline). Increased spontaneous and IL-2-induced release of IFN-gamma and TNF-alpha from NK cells were found in DAT patients compared to healthy subjects (p < 0.001), whereas no difference of serum IFN-gamma and TNF-alpha was demonstrated between DAT and control groups. Significant negative correlations among the spontaneous release of IFN-gamma and TNF-alpha from NK and the decrease of the score of cognitive function (MMSE) were found in patients with DAT. In conclusion, alterations of NKCC control and NK-derived cytokine release in DAT could be involved in the neuroinflammatory mechanism related to the progression of neurodegeneration and dementia.

Variability of interactions between neuroendocrine and immunological functions in physiological aging and dementia of the Alzheimer's type

A link between neuroendocrine and immunological changes has been suggested in the pathophysiology of dementia of the Alzheimer's type (DAT). Healthy young and old subjects and patients with DAT were recruited to evaluate the chrononeuroendocrine organization of cortisol, GH, and melatonin (MLT) secretions. The study was carried out together with the evaluation of natural killer (NK) cell function: cytotoxic activity (NKCC) and TNF-alpha and IFN-gamma release after exposure to IL-2 (100 U/mL). Moreover, a cerebral morphometric analysis of hippocampus and temporal lobe (MRI) was performed. The activation of hypothalamo-pituitary-adrenal (HPA) axis and the decrease of GH, and MLT nocturnal peaks were associated with normal NKCC and TNF-alpha/IFN-gamma in healthy elderly subjects, whereas in DAT patients the same neuroendocrine changes occurred together with abnormal NKCC (spontaneous and IL-2/IFN-beta-modulated) and with alterations of TNF-alpha/INF-gamma generation from NK. Moreover significant correlations among the increase of NKCC and TNF-alpha and the decrease of cognitive function were found in the DAT group. These correlations were associated with the impairment of nocturnal GH and MLT levels and with the relatively higher serum cortisol concentrations. Moreover, the impairment of cortisol suppression after dexamethasone (1 mg orally at 23:00) was significantly correlated with the increase of spontaneous release of TNF-alpha and with IL-2-modulated NKCC. Finally the imunoneuroendocrine alterations found in DAT were associated with the reduction of cerebral volume in hippocampus and temporal lobes. Taken together these data indicate that the immunoneuroendocrine balance is maintained in physiological aging, whereas NK immune dysregulation in DAT could contribute to altering the neuroendocrine functions and to extend the progression of neurodegeneration and dementia.

Age-related changes of the hypothalamic-pituitary-adrenal axis: pathophysiological correlates

The aim of this review was to examine the evidence for age-related changes of the hypothalamic-pituitary-adrenal (HPA) axis in both physiological and pathological aging, on the basis of the many data in the literature, as well as of our personal findings. A statistically significant circadian rhythmicity of serum cortisol was maintained in elderly subjects, even if with a reduced amplitude of the 24 h fluctuations and a trend to an increase of the serum levels in the evening and at night-time, in comparison with young controls. Furthermore, an age-related impairment of HPA sensitivity to steroid feedback was present in elderly people. The occurrence of senile dementia amplified the changes already present in physiological aging. While the cortisol secretion was generally well maintained in aging, the adrenal production of dehydroepiandrosterone and of its sulfate (DHEAS) exhibited an age-related decline. Therefore, the cortisol/DHEAS molar ratio was significantly higher in elderly subjects and even more in demented ones, than in young controls. Due to the opposite effects of cortisol and DHEAS on the brain and particularly on the hippocampal region, the imbalance between glucocorticoids and androgens occurring in physiological and even more in pathological aging, may have adverse effects on the function of this region, whose key role in learning and memory is well known.

[The best in 2000 on thrombosis]

It is nearly impossible to follow and integrate all the new information in each subspeciality of cardiology. In the last months, important data has been published which may change clinical practice. In this domain, over half the cases of suspected coronary chest pain would only require a very short stay in a chest pain unit. The history, an accurate evaluation of symptoms, the application of Bayesian analysis, ECG interpretation and serum troponine measurement, associated with a degree of clinical experience, will allow orientation of the patient to a coronary care unit or hospital discharge (with possible out-patient referral). Patients with true unstable angina will no longer be treated by continuous intravenous injection of non-fractionated heparin because, in theory and in practice, this has been replaced with subcutaneous LMW heparin.... On the other hand, the electric syringe will continue to be required for the integration of the anti-GPIIB-IIIA for the treatment of unstable angina after the recommendations published concomitantly in the United States and Europe. This type of patient, especially with a "positive" troponine, will probably not be kept waiting long before referral to the catheter laboratory for coronary angiography and revascularisation. The long-term results of the FRISC II trial are confirmed by an even earlier invasive approach (Tactics-Timi 18) using anti-GPIIb-IIIa. In the first hours, and independently of other older prognostic factors, it will be possible to "predict or compare" the risk of coronary recurrence based on the results of certain biological "markers". In many centres, cases with ST elevation on the ECG could well be included in a phase III "medical protocol", associating a half-dose thrombolytic and an anti-GPIIb-IIIa. Finally, patients who will have been admitted to the chest pain unit with a suspected pulmonary embolism, for example because they had not been treated prophylactically with aspirin before hip surgery, will probably have the choice, after d-dimer measurement, between pulmonary scintigraphy and helicoidal CT scan. If the diagnosis of pulmonary embolism is confirmed, a single subcutaneous injection of LMW heparin could replace the conventional continuous intravenous injection of heparin. The earliest possible oral anticancer ... pardon me I anticoagulant treatment should be prescribed and explained.

Pineal and pituitary-adrenocortical function in physiological aging and in senile dementia

The simultaneous evaluation of the circadian rhythm of plasma melatonin and ACTH and of serum cortisol and DHEAS represents a clinically reliable tool to appreciate the neuroendocrine changes occurring in physiological and pathological brain aging.A selective impairment of the nocturnal melatonin secretion has been observed in elderly subjects, being significantly related either to the age or to the severity of dementia. A significant increase of serum cortisol levels during evening- and night-times was found in elderly subjects, particularly if demented, when compared to young controls. Besides, both the circadian amplitude of cortisol rhythm and the nocturnal cortisol increase were significantly reduced in relation either to age or to cognitive impairment. By comparison to vascular dementia, patients with Alzheimer's disease exhibited the highest cortisol concentrations throughout the 24h. The sensitivity of the hypothalamic-pituitary-adrenal axis to the steroid feedback was significantly impaired in old subjects and particularly in the demented ones. The serum DHEAS levels were significantly lower in elderly subjects and even more in demented patients than in young controls. Consequently, a significant increase of the cortisol/DHEAS molar ratio was evident when going from young controls to healthy elderly subjects and to demented patients. In conclusion, the aging process affects many neuroendocrine functions resulting in subtle but clinically relevant consequences; the occurrence of senile dementia seems to play an additive role.

Isolated so-called apraxia of eyelid opening: report of 10 cases and a review of the literature

So-called apraxia of eyelid opening (scAEO) has been described chiefly in the context of extrapyramidal disorders. We described 10 new patients with scAEO developing in the absence of any other CNS sign and reviewed the 11 cases with isolated scAEO reported in the literature. Combining our patients and those from the literature, peak age at onset was in the 6th decade and there was a female preponderance of 2:1. The characteristic inability to initiate lid elevation was frequently associated with failure to sustain lid elevation, thus suggesting that eyelid motor control may be abnormal in isolated scAEO. Antecedent events included ocular signs and symptoms consistent with diseases of eyes or face (4 cases in our series and 2 in the literature), chronic treatment with flunarizine (1 case), and family history of dystonia (1 case). Flunarizine discontinuation led to sustained remission of the eyelid disturbance. Overall, these clues suggest the involvement of the extrapyramidal system in the pathophysiology of isolated scAEO. Familial clustering of isolated scAEO in one of our patients may be in favor of a genetic contribution. In our series, botulinum toxin administration close to the pretarsal part of the orbicularis oculi muscle significantly improved scAEO in 8/10 cases, whereas orbital/preseptal injection had no effect. We conclude that the term 'apraxia' may not be the correct descriptive term even when the eyelid disturbance occurs without any other CNS disease.

Is there any difference in PBPC mobilization between cyclophosphamide plus G-CSF and G-CSF alone in patients with non-Hodgkin's Lymphoma?

We attempted to analyze whether the use of high-dose cyclophosphamide (CTX 7g/m2, group A) plus hematopoietic growth factor (G-CSF) or G-CSF alone (10 microg/Kg, group B) as a mobilizing regimen, could result in harvesting different numbers of CD34+ cells, committed progenitors and CD34+ cells subsets. The number of CD34+ cells considered as the target for each high-dose chemotherapy was > or = 2 x 10(6) /Kg/bw. Fifteen leukaphereses procedures were necessary in group A, while 16 procedures were performed in group B. We did not observe any difference between the two groups in terms of CD34+ cells/microl in the peripheral blood (117 vs 78; p = NS), whereas in the aphereses product we found a significant difference between the two groups of patients in terms of CD34+ cells (6.41 vs 2.89 x 10(6) /Kg/bw; p = .009), CFU-GM (82.5 vs 52.3 x 10(4) /Kg/bw; p = .04). Interestingly, we noted a different distribution of CD34+/33- cells between the 2 groups (mean value 39% vs 65%; p < .05), whereas we did not find any differences regarding CD34+/38-, CD34+/Thy1+, CD34+/HLADR-. The higher number of CFU-GM/Kg/bw collected in the former group did not translate into a superior plating efficiency (27.75 vs 30.29). Furthermore, we observed a strong correlation between CD34+ cells/microl in the peripheral blood and the total number of CD34+ cells in the leukaphereses product (r = 0.97), whereas this correlation was not found in group B (r = 0.15). In both groups of patients the number of CD34+ cells collected correlated well with CFU-GM (r = 0.93; r = 0.94), but definitely we did not observe any correlation between CD34+ cells/microl and CFU-GM in patients mobilized with G-CSF alone and this did not allow us to predict the harvest accurately. Finally, we evaluated the engraftment kinetics and we did not observe any statistically significant difference between the two groups of patients.

Template/primer requirements and single nucleotide incorporation by hepatitis C virus nonstructural protein 5B polymerase

Nonstructural protein 5B (NS5B) of hepatitis C virus (HCV) possesses an RNA-dependent RNA polymerase activity responsible for viral genome RNA replication. Despite several reports on the characterization of this essential viral enzyme, little is known about the reaction pathway of NS5B-catalyzed nucleotide incorporation due to the lack of a kinetic system offering efficient assembly of a catalytically competent polymerase/template/primer/nucleotide quaternary complex. In this report, specific template/primer requirements for efficient RNA synthesis by HCV NS5B were investigated. For intramolecular copy-back RNA synthesis, NS5B utilizes templates with an unstable stem-loop at the 3' terminus which exists as a single-stranded molecule in solution. A template with a stable tetraloop at the 3' terminus failed to support RNA synthesis by HCV NS5B. Based on these observations, a number of single-stranded RNA templates were synthesized and tested along with short RNA primers ranging from two to five nucleotides. It was found that HCV NS5B utilized di- or trinucleotides efficiently to initiate RNA replication. Furthermore, the polymerase, template, and primer assembled initiation-competent complexes at the 3' terminus of the template RNA where the template and primer base paired within the active site cavity of the polymerase. The minimum length of the template is five nucleotides, consistent with a structural model of the NS5B/RNA complex in which a pentanucleotide single-stranded RNA template occupies a groove located along the fingers subdomain of the polymerase. This observation suggests that the initial docking of RNA on NS5B polymerase requires a single-stranded RNA molecule. A unique beta-hairpin loop in the thumb subdomain may play an important role in properly positioning the single-stranded template for initiation of RNA synthesis. Identification of the template/primer requirements will facilitate the mechanistic characterization of HCV NS5B and its inhibitors.

The PCNA from Thermococcus fumicolans functionally interacts with DNA polymerase delta

We have cloned the gene encoding proliferating cell nuclear antigen (PCNA) from the hyperthermophilic euryarchaeote Thermococcus fumicolans (Tfu). Tfu PCNA contains 250 amino acids with a calculated M(r) of 28,000 and is 26% identical to human PCNA. Next, Tfu PCNA was overexpressed in Escherichia coli and it showed an apparent molecular mass of 33.5 kDa. The purified Tfu PCNA was tested first with recombinant Tfu DNA polymerase I (Tfu pol) and second with calf thymus DNA polymerase delta (pol delta). When tested with the homologous Tfu pol on bacteriophage lambda DNA, large amounts of Tfu PCNA were required to obtain two- to threefold stimulation. Surprisingly, however, Tfu PCNA was much more efficient than human PCNA in stimulating calf thymus pol delta. Our data suggest that PCNA has been functionally conserved not only within eukaryotes but also from hyperthermophilic euryarchaeotes to mammals.

Carboplatin, cisplatin and paclitaxel in the treatment of patients with epithelial ovarian cancer

BACKGROUND

Prognosis of advanced ovarian cancer is unsatisfactory. Chemotherapy can be intensified combining active drugs at their highest possible doses.

PATIENTS AND METHODS

In this phase I/II trial, 77 untreated patients received escalating doses of paclitaxel (135, 155, 175, 195 and 215 mg/m2, infused over 3 hours) with carboplatin (AUC 3.6) and cisplatin (60 mg/m2). Nine, 16, 13, 8 and 3 patients were treated at the five levels, respectively. A further 28 patients were treated at the maximum tolerable dose (MTD).

RESULTS

Dose-limiting toxicities (one WHO grade 3 constipation, one grade 2 prolonged peripheral neurotoxicity and one grade 3 cardiac toxicity) occurred at 215 mg/m2 in 3 out of 3 patients. MTD was reached at level 4 paclitaxel dose (195 mg/m2). Response was evaluated in 62 patients. A complete response was achieved in 23 patients (37.1%-95% CI 25.2-50.3), including 16 (25.8%) pathological and partial response in 28 (45.2%), for an overall response rate of 82.3% (95% exact CL: 70.5%-90.8%). The probability of response was affected by the degree of initial debulking (p = 0.002) and not by the paclitaxel dose. In patients with stage III-IV disease, median progression-free survival was 17 months (95% CI 14-25). After a median follow-up of 28 months, median survival had not been reached; 2-year estimated survival was 67%.

CONCLUSION

Paclitaxel can be safely given at the dose of 195 mg/m2 in combination with carboplatin (AUC 3.6) and cisplatin (60 mg/m2). This combination is active and safe and could be considered in clinical settings requiring intensive short treatment.

RNA-dependent RNA polymerase activity encoded by GB virus-B non-structural protein 5B

Phylogenetic analysis and polyprotein organization comparison have shown that GB virus-B (GBV-B) is closely related to hepatitis C virus (HCV). In this study, the coding region for GBV-B non-structural protein 5B (NS5B) was isolated by reverse transcription-polymerase chain reaction (RT-PCR) from pooled serum of GBV-B-infected tamarins. Expression of soluble GBV-B NS5B protein in Escherichia coli was achieved by removal of a 19-amino acid hydrophobic domain at the C-terminus of the protein. The truncated GBV-B NS5B (NS5BDeltaCT19) was purified to homogeneity and shown to possess an RNA-dependent RNA polymerase (RdRp) activity in both gel-based and scintillation proximity assays. NS5BDeltaCT19 required the divalent cation Mn2+ for enzymatic activity, at an optimal concentration of 15 mM. Interestingly, Mg2+, at concentrations up to 20 mM, did not support the GBV-B NS5B activity. This differs from HCV NS5B where both Mn2+ and Mg2+ can support RdRp activity. Zn2+ was found to inhibit the activity of GBV-B NS5B, with a 50% inhibitory concentration (IC50) of 5-10 microM. Higher concentrations of monovalent salts (NaCl or KCl > 100 mM) and glycerol (> 3%) were also inhibitory. NS5BDeltaCT19 was able to bind to RNA homopolymers, but utilized most efficiently poly(C), the one with the lowest binding affinity for RNA synthesis. Mutational analysis of GBV-B NS5B demonstrated the importance of several conserved sequence motifs for enzymatic activity. Based on sequence homology ( approximately 37% identity and 52% similarity) between GBV-B and HCV NS5B proteins, the active GBV-B RdRp provides a good surrogate assay system for HCV polymerase studies.

Rice: old or new food?

The aim of this paper is to focus the attention on the role of rice not only as food, but as a natural dietetic product. In fact, a regular intake of rice may contribute to the well-being of subjects due to the particular positive qualities of this food (high digeribility, high biological value of amino acids, high content of EFA, positive sodium/chloride rate, high content of selenium and silicium, antihypertensive effect) which have been scientifically confirmed. Stress is laid on the particular nutritional composition of rice, underlying the dietetic usefulness of this food and the new frontiers of rice as functional food.

Paternal concentrations of dioxin and sex ratio of offspring

BACKGROUND

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD or dioxin), is commonly considered the most toxic man-made substance. We have previously shown that high serum concentrations of TCDD in parents from Seveso, Italy, were linked to their having a relative increase in the number of female births after the parents exposure to a release of dioxin in 1976. We have continued the study to determine whether the parents' sex and/or age at exposure affected the sex ratio of their children.

METHODS

We measured the TCDD concentrations in serum samples from potentially exposed parents collected in 1976 and 1977, and investigated the sex ratio of their offspring.

FINDINGS

Serum samples were collected from 239 men and 296 women. 346 girls and 328 boys were born to potentially exposed parents between 1977 and 1996, showing an increased probability of female births (lower sex ratio) with increasing TCDD concentrations in the serum samples from the fathers (p=0.008). This effect starts at concentrations less than 20 ng per kg bodyweight. Fathers exposed when they were younger than 19 years of age sired significantly more girls than boys (sex ratio 0.38 [95% CI 0.30-0.47]).

INTERPRETATION

Exposure of men to TCDD is linked to a lowered male/female sex ratio in their offspring, which may persist for years after exposure. The median concentration of dioxin in fathers in this study is similar to doses that induce epididymal impairments in rats and is about 20 times the estimated average concentration of TCDD currently found in human beings in industrialised countries. These observations could have important public-health implications.

Evaluation of the circadian profiles of serum dehydroepiandrosterone (DHEA), cortisol, and cortisol/DHEA molar ratio after a single oral administration of DHEA in elderly subjects

Aging is associated with a selective decline in circulating levels of dehydroepiandrosterone (DHEA) and its sulfate, with no major changes in cortisol secretion. In young subjects, serum levels of both DHEA and cortisol are regulated according to a circadian rhythm, and an age-related attenuation of DHEA, but not cortisol, circadian rhythmicity has been reported. Several trials have evaluated the effects of DHEA supplementation in elderly subjects, although the results are still controversial. However, no data are available on the 24-hour profile of DHEA circulating levels in elderly subjects with DHEA administration. In the present study, we evaluated the circadian rhythms of DHEA, cortisol, and the cortisol/DHEA molar ratio in old subjects treated with either placebo (old-PL) or a single 50-mg dose of DHEA (old-D), both administered orally at 0700 hours. For each variable, the circadian profiles were compared with those obtained in young control subjects. The group of young subjects displayed a circadian rhythm for both DHEA and cortisol serum concentrations but no rhythm for the cortisol/DHEA molar ratio. In the old-PL group, the circadian rhythm of DHEA was completely abolished, whereas significant rhythms for both cortisol and the cortisol/DHEA molar ratio were observed. Particularly, at each time point, the cortisol/DHEA molar ratio was significantly higher in these subjects versus the young group. In the old-D group, the circadian rhythm of DHEA was completely restored and was comparable to that observed in the young group. Analogous to the observations in young subjects, the profile of the cortisol/DHEA molar ratio in old-D subjects did not display any circadian rhythmicity, the values being almost completely comparable to those observed in young controls. Our data demonstrate that the circadian rhythm of DHEA is totally abolished in elderly subjects. A single 50-mg dose of DHEA administered orally at 0700 hours restores the circadian rhythmicity of serum DHEA and almost completely normalizes the 24-hour profile of the cortisol/DHEA molar ratio in old subjects without affecting the cortisol circadian rhythm.

Relationships between total CD34+ cells reinfused, CD34+ subsets and engraftment kinetics in breast cancer patients

BACKGROUND AND OBJECTIVE

The aim of the present study was to evaluate the correlation between the number of CD34+ cells transfused and the duration of hypoplasia, and the relationship between various CD34+ subsets (CD34+/33-; CD34+/38-; CD34+/ HLA-DR-; CD34+/Thy-1+) and engraftment kinetics in a series of patients with breast cancer treated with high doses of thiotepa and melphalan.

DESIGN AND METHODS

We treated 42 consecutive patients: 19 in an adjuvant context (>= 4 positive axillary nodes) and 23 for metastatic disease. A combination of thiotepa 600 mg/m(2) and melphalan 140-160 mg/m(2) was administered as the conditioning regimen. All patients received peripheral blood progenitor cells (PBPC) and growth factors for hematopoietic rescue.

RESULTS

In univariate analysis, we found a significant relationship between the number of CD34+ cells reinfused and the time to hematologic recovery and the duration of hospital stay. We observed an inverse correlation between the number of CD34+ cells reinfused and the units of platelets transfused. Cox multivariate analysis confirmed that the number of CD34+ cells reinfused is the most effective predictor of time to hematologic recovery. CFU-GM resulted to be a better predictor of the duration of hospitalization.

INTERPRETATION AND CONCLUSIONS

We found a significant relationship between the number of PBPC reinfused and the time to hematologic recovery after high doses of thiotepa and melphalan. In our experience, the numbers of subsets of CD34+ cells infused did not give compared additional information to that provided by the total number of CD34+ cells infused.

Phase I study with weekly cisplatin-paclitaxel and concurrent radiotherapy in patients with carcinoma of the cervix uteri

BACKGROUND

Cisplatin and paclitaxel are active in cervical cancer and both are able to potentiate the effects of radiotherapy. In this study we evaluated the maximum-tolerated dose (MTD) of paclitaxel in combination with a fixed dose of cisplatin when given weekly concurrently with pelvic radiotherapy to patients with carcinoma of the cervix uteri.

PATIENTS AND METHODS

Eighteen patients with cervical cancer were enrolled in this study. Cisplatin (30 mg/m2) and paclitaxel (starting dose 40 mg/m2; 5 mg/m2 escalation per level) were given on day 1 of radiotherapy and then weekly for six times. Radiotherapy was given to the pelvis with a four-field box technique for five days each week. Patients received 65 Gy in 1.8 Gy fractions. Cohorts of three patients were enrolled at each level and three further patients were included if one or two dose-limiting severe adverse events (SAE) were recorded. SAE was defined as grade 3 or 4 nonhematologic toxicity, excluding nausea or vomiting and alopecia, grade 4 neutropenia or thrombocytopenia, and prolonged (> 1 week) neutropenia or thrombocytopenia.

RESULTS

Four levels were studied (paclitaxel 40, 45, 50, 55 mg/m2) with three, five, four and six patients enrolled, respectively. The MTD of paclitaxel was found at 50 mg/m2/wk and cisplatin 30 mg/m2/wk. Diarrhea was the dose-limiting toxicity. Thirteen patients were evaluable for response: seven complete and five partial responses were obtained with an overall response rate of 92.3%.

CONCLUSIONS

The MTD of paclitaxel is 50 mg/m2/wk when associated to cisplatin 30 mg/m2/wk and concurrent pelvic radiotherapy. Diarrhea is the dose limiting side effect. Preliminary data suggest that concurrent chemoradiotherapy with paclitaxel and cisplatin could be a very active treatment for patients with locally advanced carcinoma of the cervix.

Aspirin and sodium salicylate inhibit endothelin ETA receptors by an allosteric type of mechanism

Aspirin is a commonly used drug with a wide pharmacological spectrum including antiplatelet, anti-inflammatory, and neuroprotective actions. This study shows that aspirin and sodium salicylate, its major blood metabolite, reverse contractile actions of endothelin-1 (ET-1) in isolated rat aorta and human mammary arteries. They also prevent the intracellular Ca(2+) mobilizing action of ET-1 in cultured endothelial cells but not those of neuromedin B or UTP. Inhibition of the actions of ET-1 by salicylates is apparently competitive. Salicylates inhibit (125)I-ET-1 binding to recombinant rat ETA receptors. Salicylic acid promotes dissociation of (125)I-ET-1 ETA receptor complexes both in the absence and the presence of unlabeled ET-1. It has no influence on the rate of association of (125)I-ET-1 to ETA receptors. Salicylates do not promote dissociation of (125)I-ET-1 ETB receptor complexes. Salicylates potentiate relaxing actions of receptor antagonists such as bosentan. It is concluded that salicylates are allosteric inhibitors of ETA receptors. The results also suggest that: 1) irreversible ET-1 binding probably limits actions of receptor antagonists in vivo, and 2) an association of salicylates and ETA receptor antagonists should be used to evaluate the physiopathological role of ET-1 and may be of therapeutic interest in the treatment of ischemic heart disease.

Association between changes in adrenal secretion and cerebral morphometric correlates in normal aging and senile dementia

The circadian organization of adrenal secretion was studied in 23 healthy elderly subjects, 23 elderly demented patients and 10 healthy young subjects, in order to investigate the relationships between the hypothalamic-pituitary-adrenal axis and some cerebral morphometric parameters. The cerebral morphometric analysis was performed in some subjects of the three groups by MRI. A significant increase in cortisol levels during evening and nighttime was found in both groups of the aged subjects. In elderly subjects, particularly if demented, the mean serum dehydroepiandrosterone sulfate (DHEAs) levels throughout the 24-hour cycle were significantly lower than in young controls. A significant reduction of the hippocampal and temporal volume and an enlargement of the lateral ventricles were found in aged subjects, these changes being significantly related to subjects' age. Moreover, the hippocampal volume was positively correlated with the circadian mesor of DHEAs (i.e., the circadian rhythm adjusted mean) and with the cortisol nocturnal increase. Our data may suggest the existence of a link between the selective impairment of cortisol secretion and DHEAs levels, and the progression of hippocampal degeneration.

Hemorheological changes and overproduction of cytokines from immune cells in mild to moderate dementia of the Alzheimer's type: adverse effects on cerebromicrovascular system

An association between hemorheological alterations (i.e., whole-blood and plasma hyperviscosity, reduced erythrocyte deformability, increased red cell aggregation, hyperfibrinogenemia and increased acute-phase protein levels) and the mild stage of senile dementia of the Alzheimer's type (DAT) was suggested in the present study. In particular, hyperfibrinogenemia and the increase of erytrhocyte aggregation were correlated with the increased generation and release of TNF-alpha and IFN-gamma (spontaneous release and IL-2-modulated release) from natural killer (NK) lymphocytes (CD16+, CD56+, CD3- cells) of patients with DAT; whereas a normal cytokine release from NK cells was found in healthy old subjects and in patients with vascular dementia (VaD). The in vitro and in vivo administration of the hemorheologic drug pentoxifylline (PTX) significantly reduced spontaneous and IL-2-modulated cytokine overproduction from NK cells (in vitro effects with 500 U/ml and 1000 U/ml/NK cells) and improved all the hemorheological parameters. Taken together, these data suggest that disturbances of cerebrovascular flow and of hemorheology could be considered a negative component related to the pathogenesis and progression of DAT neurodegeneration. The association between hemorheological changes and alterations of TNF-alpha and IFN-gamma release from NK may indicate a potential immunorheologic mechanism associated with cerebrovascular damage in DAT and could suggest the use of vascular protective drugs as support of the main pharmacological and non-pharmacological therapy of AD.

De novo initiation of RNA synthesis by hepatitis C virus nonstructural protein 5B polymerase

RNA-dependent RNA polymerase (RdRp) encoded by positive-strand RNA viruses is critical to the replication of viral RNA genome. Like other positive-strand RNA viruses, replication of hepatitis C virus (HCV) RNA is mediated through a negative-strand intermediate, which is generated through copying the positive-strand genomic RNA. Although it has been demonstrated that HCV NS5B alone can direct RNA replication through a copy-back primer at the 3' end, de novo initiation of RNA synthesis is likely to be the mode of RNA replication in infected cells. In this study, we demonstrate that a recombinant HCV NS5B protein has the ability to initiate de novo RNA synthesis in vitro. The NS5B used HCV 3' X-tail RNA (98 nucleotides) as the template to synthesize an RNA product of monomer size, which can be labeled by ¿gamma-(32)Pnucleoside triphosphate. The de novo initiation activity was further confirmed by using small synthetic RNAs ending with dideoxynucleotides at the 3' termini. In addition, HCV NS5B preferred GTP as the initiation nucleotide. The optimal conditions for the de novo initiation activity have been determined. Identification and characterization of the de novo priming or initiation activity by HCV NS5B provides an opportunity to screen for inhibitors that specifically target the initiation step.

DNA polymerase switching: II. Replication factor C abrogates primer synthesis by DNA polymerase alpha at a critical length

A crucial event in DNA replication is the polymerase switch from the synthesis of a short RNA/DNA primer by DNA polymerase alpha/primase to the pro?cessive elongation by DNA polymerase delta. In order to shed light on the role of replication factor C (RF-C) in this process, the effects of RF-C on DNA polymerase alpha were investigated. We show that RF-C stalls DNA polymerase alpha after synthesis of approximately 30 nucleotides, while not inhibiting the polymerase activity per se. This suggested that RF-C and the length of the primer may be two important factors contributing to the polymerase switch. Furthermore the DNA binding properties of RF-C were tested. Band shift experiments indicated that RF-C has a preference for 5' recessed ends and double-stranded DNA over 3' ends. Finally PCNA can be loaded onto a DNA template carrying a RNA primer, suggesting that a DNA moiety is not necessarily required for the loading of the clamp. Thus we propose a model where RF-C, upon binding to the RNA/DNA primer, influences primer synthesis and sets the conditions for a polymerase switch after recruiting PCNA to DNA.

[The best of thrombosis and thromboembolic disease in 1999]

1999 has been a good year in the field of innovation in thrombosis. In coronary syndrome without ST elevation: low molecular weight heparin has been confirmed to be more effective than non-fractionated heparin (enoxaparin) and to improve the prognosis of non-revascularised patients (dalteparin) after the hospital phase; hirudin has been shown to be more effective in terms of incidence of myocardial infarction and recurrence of angina than non-fractionated heparin without a higher incidence of bleeding complications; the anti-GP IIb-IIIa (abciximab) has confirmed all its advantages at 6 months and 1 year after a coronary event. The association of heparin and aspirin, which has been the mainstay of antithrombotic treatment of acute coronary syndromes without ST elevation, will soon be improved upon at the beginning of the third millennium. In myocardial infarction, medical thrombolysis has probably reached a turning point in its history. The association of half doses of rt-Pa and anti-GP IIb-IIIa has been shown to be more effective in obtaining good reflow than the thrombolytic agent alone at conventional doses. These results were obtained without any increase in bleeding complication. The same anti-GP IIb-IIIa also improve mechanical revascularisation by optimising reperfusion after the 24th hour. This benefit is rapidly transformed into reduced left ventricular dysfunction. Pulmonary embolism remains a critical illness as the ICOPER registry reports a 3 year mortality of nearly 16%. This emphasises the importance of early diagnosis which is usually possible without resorting to invasive procedures and by modulating all the results of paraclinical investigations with respect to the pretest clinical probability.

Mutational analysis of bovine viral diarrhea virus RNA-dependent RNA polymerase

Recombinant bovine viral diarrhea virus (BVDV) nonstructural protein 5B (NS5B) produced in insect cells has been shown to possess an RNA-dependent RNA polymerase (RdRp) activity. Our initial attempt to produce the full-length BVDV NS5B with a C-terminal hexahistidine tag in Escherichia coli failed due to the expression of insoluble products. Prompted by a recent report that removal of the C-terminal hydrophobic domain significantly improved the solubility of hepatitis C virus (HCV) NS5B, we constructed a similar deletion of 24 amino acids at the C terminus of BVDV NS5B. The resulting fusion protein, NS5BDeltaCT24-His, was purified to homogeneity and demonstrated to direct RNA replication via both primer-dependent (elongative) and primer-independent (de novo) mechanisms. Furthermore, BVDV RdRp was found to utilize a circular single-stranded DNA as a template for RNA synthesis, suggesting that synthesis does not require ends in the template. In addition to the previously described polymerase motifs A, B, C, and D, alignments with other flavivirus sequences revealed two additional motifs, one N-terminal to motif A and one C-terminal to motif D. Extensive alanine substitutions showed that while most mutations had similar effects on both elongative and de novo RNA syntheses, some had selective effects. Finally, deletions of up to 90 amino acids from the N terminus did not significantly affect RdRp activities, whereas deletions of more than 24 amino acids at the C terminus resulted in either insoluble products or soluble proteins (DeltaCT179 and DeltaCT218) that lacked RdRp activities.

Combination therapy with the farnesyl protein transferase inhibitor SCH66336 and SCH58500 (p53 adenovirus) in preclinical cancer models

SCH66336 is a p.o.-active, farnesyl protein transferase inhibitor. SCH66336 inhibits farnesylation of RAS and other proteins in tumor cells and suppresses tumor growth in human xenograft and transgenic mouse cancer models in vivo. SCH58500 is a replication-deficient, recombinant adenovirus, which expresses the human p53 tumor suppressor. In preclinical models, SCH58500 has therapeutic efficacy against a wide range of human tumor types containing nonfunctional p53 and enhanced activity in combination with many chemotherapeutic drugs. Here we report that combination therapy with SCH66336 and SCH58500 has synergistic or additive antiproliferative effects on a panel of tumor cells lines in vitro. The efficacy of the three-drug combination of SCH66336, SCH58500, and paclitaxel was also examined in vitro. Each two-drug interaction displayed such marked synergy, the addition of a third drug to the statistical model could only yield additivity. Greater combined efficacy for SCH66336 and SCH58500 was also observed in vivo in the DU-145 human prostate and wap-ras/F transgenic mouse cancer models.

Toxicokinetics of 1,2-diethylbenzene in male Sprague-Dawley rats-part 1: excretion and metabolism of [(14)C]1,2-diethylbenzene

The excretion and metabolism of neurotoxic 1,2-diethylbenzene (1, 2-DEB) was studied in male Sprague-Dawley rats after i.v. (1 mg/kg) or oral (1 or 100 mg/kg) administration of 1,2-diethyl[U-(14)C]benzene ([(14)C]1,2-DEB). Whatever the treatment, radioactivity was mainly excreted in urine (65-76% of the dose) and to a lower extent in feces (15-23% of the dose), or via exhaled air (3-5% of the dose). However, experiments with rats fitted with a biliary cannula demonstrated that about 52 to 64% of the administered doses (1 or 100 mg/kg) were initially excreted in bile. Biliary metabolites were extensively reabsorbed from the gut and ultimately excreted in urine after several enterohepatic circulations. Insignificant amounts of unchanged 1,2-DEB were recovered in the different excreta (urine, bile, and feces). As reported previously, presence of 1-(2'-ethylphenyl)ethanol (EPE) was confirmed in urine and demonstrated in bile and feces. The two main [(14)C]1,2-DEB metabolites accounted for 57 to 79% of urinary and biliary radioactivity, respectively. Beta-Glucuronidase hydrolysis and electron impact mass spectra results strongly supported their glucuronide structure. Additionally, these two main metabolites were thought to be the glucuronide conjugates of the two potential enantiomers of EPE. The results indicate that the main initial conversion step of the primary metabolic pathway of 1,2-DEB appears to be the hydroxylation of the alpha-carbon atom of the side chain. The presence of two glucuronide conjugates of EPE in the urine in a ratio different from one suggests that the metabolic conversion of 1, 2-DEB is under stereochemical control.

Solution structure of a recombinant mouse major urinary protein

Major urinary proteins (MUPs) form an ensemble of protein isoforms which are expressed and secreted by sexually mature male mice only. They belong to the lipocalin superfamily and share with other members of this family the capacity to bind hydrophobic molecules, some of which are odorants. MUPs, either associated with or free of their natural ligands, play an important role in the reproductive cycle of these rodents by acting as pheromones. In fact, they are able to interact with receptors in the vomeronasal organ of the female mice, inducing hormonal and physiological responses by an as yet unknown mechanism. In order to investigate the structural and dynamical features of these proteins in solution, one of the various wild-type isoforms (rMUP: 162 residues) was cloned and subsequently isotopically labeled. The complete 1H, 13C and 15N resonance assignment of that isoform, achieved by using a variety of multidimensional heteronuclear NMR experiments, has been reported recently. Here, we describe the refined high-resolution three-dimensional solution structure of rMUP in the native state, obtained by a combination of distance geometry and energy minimization calculations based on 2362 NOE-derived distance restraints. A comparison with the crystal structure of the wild-type MUPs reveals, aside from minor differences, a close resemblance in both secondary structure and overall topology. The secondary structure of the protein consists of eight antiparallel beta-strands forming a single beta-sheet and an alpha-helix in the C-terminal region. In addition, there are several helical and hairpin turns distributed throughout the protein sequence, mostly connecting the beta-strands. The tertiary fold of the beta-sheet creates a beta-barrel, common to all members of the lipocalin superfamily. The shape of the beta-barrel resembles a calyx, lined inside by mostly hydrophobic residues that are instrumental for the binding and transport of small nonpolar ligand molecules.

Crystal structure of the RNA-dependent RNA polymerase from hepatitis C virus reveals a fully encircled active site

Various classes of nucleotidyl polymerases with different transcriptional roles contain a conserved core structure. Less is known, however, about the distinguishing features of these enzymes, particularly those of the RNA-dependent RNA polymerase class. The 1. 9 A resolution crystal structure of hepatitis C virus (HCV) nonstructural protein 5B (NS5B) presented here provides the first complete and detailed view of an RNA-dependent RNA polymerase. While canonical polymerase features exist in the structure, NS5B adopts a unique shape due to extensive interactions between the fingers and thumb polymerase subdomains that serve to encircle the enzyme active site. Several insertions in the fingers subdomain account for intersubdomain linkages that include two extended loops and a pair of antiparallel alpha-helices. The HCV NS5B apoenzyme structure reported here can accommodate a template:primer duplex without global conformational changes, supporting the hypothesis that this structure is essentially preserved during the reaction pathway. This NS5B template:primer model also allows identification of a new structural motif involved in stabilizing the nascent base pair.

Changes of serum allopregnanolone levels in the first 2 years of life and during pubertal development

Allopregnanolone is the best characterized among neurosteroids, and its role in the control of neuroendocrine axes has attracted increasing interest recently. However, there is no available information about circulating levels of allopregnanolone during infancy, childhood and puberty. We studied two groups of children: 1) those aged between 0 and 2 y (n = 72), and 2) those aged between 6 and 18 y, at different Tanner's stages (n = 82). In each of these patients, serum allopregnanolone, progesterone, cortisol, and dehydroepiandrosterone levels were evaluated after informed consent; allopregnanolone was measured by RIA after acid extraction on cartridge. There was no significant variation of serum allopregnanolone levels either in male and female children during the first 2 y of life. Furthermore, although serum dehydroepiandrosterone levels showed a significant decrease, inversely correlated with age of the children (p < 0.01), serum cortisol and progesterone levels showed a significant age-related increase during the first 2 y of life. Cortisol and allopregnanolone levels were positively correlated (p < 0.01). During puberty, we observed a progressive increase in serum allopregnanolone levels in both boys and in girls, which were higher at Tanner' s stage IV-V (0.7+/-0.01 nM; mean +/- SEM) than at stages I-II (0.32+/-0.02 nM; p < 0.01); mean levels were significantly higher at puberty than in the first 2 y of life (p < 0.01). Furthermore, during puberty, serum progesterone and dehydroepiandrosterone levels also increased progressively with age in both boys and girls. Allopregnanolone and dehydroepiandrosterone levels were positively correlated throughout puberty. The present results indicate that serum allopregnanolone levels do not change during the first 2 y of life but increase during pubertal development, suggesting that this steroid may be involved in the adaptive neuroendocrine mechanisms related to puberty.

Serum glucagon concentration and hyperinsulinaemia influence renal haemodynamics and urinary protein loss in normotensive patients with central obesity

OBJECTIVES

Insulin-resistance syndrome and hyperinsulinaemia are linked with cardiovascular disease (CVD) in the obese population. In particular, cardiovascular risk is more frequent in central obesity and is associated with microalbuminuria (MA). MA and changes of glomerular permeability to proteins in obesity might be related with renal haemodynamic modifications (that is glomerular hyperfiltration). Since glucagon is physiologically involved in renal haemodynamic regulation, the purpose of this study was to examine whether changes of circulating glucagon levels might haemodynamically induce MA and proteinuria in patients with central obesity.

SUBJECTS

Forty normotensive obese out-patients, 22 with central (CO group) and 18 with peripheral (PO group) body fat distribution and 11 healthy subjects.

MEASUREMENTS

Serum insulin and glucagon concentrations (fasting and after oral glucose tolerance test (OGTT)) by radio immuno assay (RIA); glomerular filtration rate (GFR, isotopic); total clearances and urinary excretion rates of albumin (AER), IgG (IgGER) and alpha1 microglobulin (computerized immunonephelometry).

RESULTS

GFR and insulin concentrations (fasting and during OGTT) were higher in the CO than the PO group. Fasting glucagon concentrations were increased, and not physiologically suppressed during OGTT in patients with CO (fasting, P<0.05; OGTT 60 and 120 min, P<0.001 vs PO group). Moreover, glucagon concentrations were significantly correlated with GFR in the CO group (fasting, r=0.49, P<0.05; 60 min after OGTT, r=0.58, P<0.01); whereas no correlations were found in the PO group. Higher AER (P<0.001), IgGER (P<0.001) and alpha1 microglobulin (P<0.05) urinary concentrations were found in patients with CO than in the PO group.

CONCLUSIONS

The increase of serum glucagon concentrations may be associated with the enhancement of GFR in patients with central obesity. Glomerular hyperfiltration might influence the development of MA and of proteinuria by means of a haemodynamic mechanism so contributing to increase the risk of renal microvascular complications and of CVD in central obesity.

Dehydroepiandrosterone sulfate enhances natural killer cell cytotoxicity in humans via locally generated immunoreactive insulin-like growth factor I

Experimental and clinical investigations suggest the hypothesis that dehydroepiandrosterone sulfate (DHEAS) can positively influence natural killer (NK) immunity via locally produced insulin-like growth factor I (IGF-I) from NK cells. In the present study, the NK cell cytotoxicity (NKCC) and IGF-I levels in the supernatant of NK cells were studied at baseline and after exposure to various molar concentrations of DHEAS (from 10(-5)-10(-8) mol/L x mL/7.75 x 10(6) NK cells) in healthy subjects of young and old age. DHEAS-induced NKCC was also determined after DHEAS coincubation with somatostatin-14 (10-6) mol/L x mL/7.75 x 10(6) NK cells) and with interleukin-2 (IL-2; 100 IU/mL x 7.75 x 10(6) NK cells). NK cells were previously isolated by Ficoll-Hypaque density gradient and then by immunomagnetic procedure; the purity obtained was 97 +/- 1%. NKCC was determined against K562 tumoral targets. We observed that the increase in NKCC after DHEAS exposure was dose dependent and was correlated with the amount of IGF-I released in the supernatant of cultured NK cells. NKCC and IGF-I generation from NK cells were more elevated in healthy elder subjects than in healthy young subjects. The coincubation of DHEAS with somatostatin-14 significantly suppressed NKCC and IGF-I release from NK in both groups, whereas higher NKCC was found after DHEAS plus IL-2 exposure than after incubation with DHEAS alone. Taken together, this study suggests a role for NK-generated IGF-I in the modulation of NKCC by DHEAS in humans. Although DHEAS may contribute to the IL-2-mediated NKCC, its activity on NK cytolytic function can be dependent on a autocrine mechanism (IGF-I-mediated), probably independent of cytokine activation. The higher NKCC response to DHEAS found in old subjects than in younger might counterbalance the age-dependent decline in circulating DHEAS, thus contributing to maintain the pattern of NK immunity during aging.

Usefulness of proton magnetic resonance spectroscopy in differentiating parkinsonian syndromes

Proton magnetic resonance spectroscopy ((1)H-MRS) was performed in patients with a clinical diagnosis of idiopathic Parkinson's disease (IPD), multiple system atrophy (MSA) or progressive supranuclear palsy (PSP) in order to assess metabolic differences between the three groups of patients. Single-volume (1)H-MRS, localized to the lentiform nucleus, was carried out in 19 IPD patients, 14 MSA patients, 11 PSP patients and 12 age-matched healthy subjects. The signals of N-acetylaspartate (NAA), choline-containing compounds (Cho) and creatine-phosphocreatine (Cr) were evaluated as peak area ratios. The NAA/Cho peak ratio was significantly reduced in MSA and in PSP patients compared to IPD patients and to controls. The NAA/Cr peak ratio was significantly reduced in MSA, in PSP and in IPD patients compared to controls, but only in MSA compared to IPD patients. The NAA reduction in the basal ganglia of MSA and PSP patients may reflect a neuronal loss or damage. Single-volume (1)H-MRS may be a useful tool in differentiating MSA and PSP from IPD patients.

A phase I study of paclitaxel and epirubicin, without and with filgrastim, for the treatment of platinum-resistant advanced ovarian cancer

The aim of the study was to determine the maximum tolerated dose (MTD) of epirubicin combined with a fixed dose of paclitaxel, without and with support of filgrastim, in patients with platinum resistant or refractory ovarian cancer. Paclitaxel (150 mg/m2) and epirubicin (starting dose 90 mg/m2, 15 mg/m2 escalation per level) were given on day 1, every 28 days for 4-6 cycles. Filgrastim (F) (5 microg/kg/die) was given in case of grade 4 leukopenia (levels without support) or from day 4 up to leukocyte count >10,000/mm3 after nadir (levels with support). Cohorts of 3 patients were enrolled at each level and further 3 patients were planned if 1 or 2 unacceptable toxic events (UTE) were registered. MTD was determined first without and then with filgrastim. Four levels were studied (90, 90+F, 105+F, 120+F) with 4, 6, 5 and 4 patients enrolled, respectively. UTE (grade 4 neutropenia) were observed in 3 patients at level 1. Thus, 90 mg/m2 was the MTD for epirubicin without filgrastim. MTD of epirubicin with filgrastim was not reached at 120 mg/m2. Hematological toxicity was mild. Grade 3 mucositis was reported in 1 patient. Among the 14 patients with measurable or evaluable disease, 3 objective responses were observed (1 complete and 2 partial) for an overall response rate of 21.4%. The combination of paclitaxel 150 mg/m2 and epirubicin at 120 mg/m2 with filgrastim is a feasible therapy. Grade 4 leukopenia is the dose limiting toxicity using epirubicin at 90 mg/m2 without filgrastim.

Atherosclerosis of the thoracic aorta and aortic debris as a marker of poor prognosis: benefit of oral anticoagulants

OBJECTIVES

Our aim was to confirm the poor prognosis related to thoracic aortic plaques, in particular aortic debris, diagnosed by transesophageal echocardiography (TEE) and to evaluate patients' prognosis as a function of the antithrombotic treatment.

BACKGROUND

Aortic atheroma (AA) has been widely studied. However, it is still not known which antithrombotic treatment should be adopted in this disease.

METHODS

Patients referred for TEE and diagnosed with AA were followed. All thromboembolic events and deaths were recorded during a follow-up of 22+/-10 months. The antithrombotic treatment to be adopted was left to the discretion of the practitioner in charge of the patient.

RESULTS

Aortic atheroma was found in 12% of all TEE performed and in 27.5% of TEE performed for stroke. This prevalence was higher when no other etiology existed to explain the stroke (p < 0.001). During follow-up, an end point occurred in 22.5% of patients. The more severe the AA the greater the incidence of events (p = 0.007). A higher mortality rate is shown in patients with aortic debris (p = 0.049). Compared with those treated with oral anticoagulants, patients with aortic plaques >4 mm thick treated with antiplatelets had more embolic events and combined events (p = 0.01 and p = 0.007, relative risk [RR] = 5.9, 95% confidence interval [CI] = 1.4 to 15, respectively); patients with aortic debris had more combined events and a higher mortality rate (p = 0.001, RR = 7.1, 95% CI = 1.2 to 19 and p = 0.019, RR = 9.1, 95% CI = 1.2 to 25, respectively).

CONCLUSIONS

We confirm the high incidence of vascular events and deaths in patients with AA. We have demonstrated, for the first time in this condition, a better outcome among patients treated with oral anticoagulants versus antiplatelets.

Late survival after abdominal aortic aneurysm repair

OBJECTIVES

This study was undertaken to determine the late survival of patients operated successfully for abdominal aortic aneurysm (AAA) repair, to compare survival data with that of the age- and sex-matched general population, to identify the causes of late death, and to determine the factors influencing late survival.

MATERIALS AND METHODS

A total of 187 consecutive patients underwent elective surgical AAA repair between January 1987 and December 1991. There were 11 postoperative deaths (early mortality rate 5.9%). The remaining 176 patients formed the basis of this cohort-based retrospective study. Six patients (3.4%) were lost to follow-up. Mean follow-up was 71 months.

RESULTS

A total of 70 patients (39.8%) died during the study period. Coronary artery disease (CAD) and cancer were the two main causes. The survival rate at five years (71.6%) was lower than that of the sex- and age-matched general population (90.6%). Neither arterial hypertension nor CAD had any influence on late survival. In contrast, age and chronic renal failure were predictive variables of late survival.

CONCLUSIONS

The life expectancy of patients who undergo successful AAA repair is not as good as that of the age- and sex-matched general population. Late survival depends on the patients' age at the time of surgery and the existence of preoperative chronic renal failure.

Phase II study of cisplatin and vinorelbine as first-line chemotherapy in patients with carcinoma of the uterine cervix

PURPOSE

To evaluate the activity and toxicity of the combination of cisplatin (80 mg/m2 day 1) and vinorelbine (25 mg/m2 days 1 and 8) in patients with carcinoma of the uterine cervix that has not been previously treated with chemotherapy.

PATIENTS AND METHODS

Fifty patients with cervical cancer were enrolled onto this study (27 stage IB-III, 23 stage IVB-recurrent). A two-stage optimal Simon design was applied. Thirteen responders of 29 treated patients were required to proceed beyond the first stage, and 28 responders were needed overall.

RESULTS

Hematologic toxicity was mild, with neutropenia being the most frequent side effect. Nonhematologic toxicity was frequent but never severe; one patient had grade 3 peripheral neurotoxicity. Objective responses were recorded for 32 patients (64%): 11 patients (22%) achieved a complete response (CR) and 21 patients (42%) achieved a partial response (PR). The response rate was 81.5% in patients with IB-III stage (25.9% CR rate) and 43.5% in patients with IVB-recurrent disease (17.4% CR rate). Responses were seen both in stage IVB patients (one CR and two PRs, for an overall rate of 37.5%) and in patients with recurrent disease (three CRs + four PRs, for an overall rate of 46.7%).

CONCLUSION

The combination of cisplatin and vinorelbine is an active regimen in the treatment of patients with early-stage and advanced carcinoma of the uterine cervix. The hematologic and nonhematologic toxicity of this combination is mild.

Travel as a risk factor for venous thromboembolic disease: a case-control study

BACKGROUND

The link between travel and the risk of venous thromboembolic disease (VTED) has been widely suspected. However, only cases or series of cases have been reported in the literature.

STUDY OBJECTIVES

By means of a case-control study, we sought to confirm this relationship and to determine the main features, if any, of these posttravel VTEDs.

DESIGN

The history, in particular the history of recent travel, of 160 patients presenting in our department with VTED was scrupulously investigated. All journeys undertaken during the preceding 4 weeks and lasting > 4 h by whatever means of transport were considered. The same questionnaire was submitted to a control group.

RESULTS

When the two groups of patients are compared, a history of recent travel is found almost four times more frequently in the VTED group (p < 0.0001). The odds ratio for having a VTED in patients who traveled was 3.98 (95% confidence interval, 1.9 to 8.4). Means of travel used included the train in 2 cases, airplane in 9, and car in 28. Mean duration of travel was 5.4+/-2.1 h. These posttravel VTEDs are not confined to a specific location, seem to involve no particular predisposition, and are more often "idiopathic." This fact supports the hypothesis that travel alone can produce vein clot formation.

CONCLUSIONS

A history of recent travel is a risk factor for VTED. Posttravel venous thrombotic events can occur after short journeys in patients with no other risk factors or concomitant disease

Aspiration needle biopsy in preoperative selection of thyroid nodules defined at fine-needle aspiration as microfollicular lesions

The palpable thyroid nodules that are diagnosed as microfollicular by fine-needle aspiration cytologic analysis are usually excised for the low probability that the nodule is a well-differentiated follicular cancer. The authors retrospectively assess the use of aspiration needle biopsy (either 16- or 18-gauge needles) in the preoperative selection of the nodules diagnosed as microfollicular at fine-needle aspiration (either 20- or 22-gauge needles). Aspiration needle biopsy is a type of large needle biopsy that is a relatively easy and innocuous method of obtaining tissue fragments for preoperative histologic examination of palpable thyroid nodules. From 1980 through 1996, 6,314 patients with palpable thyroid nodules were examined by fine-needle aspiration; 29.5% of these nodules were also examined preoperatively by aspiration needle biopsy. Of all the patients with nodules, 6% received a fine-needle aspiration diagnosis of microfollicular nodule. Two hundred sixty of the 380 nodules (68%) that were diagnosed as microfollicular at fine-needle aspiration were also examined by aspiration needle biopsy; inadequate specimens were obtained in 17% of cases; pure microfollicular structure was confirmed by aspiration needle biopsy in 35% of the nodules; and aspiration needle biopsy showed the remaining 48% to contain a macrofollicular component suggesting a benign hyperplastic lesion. Seventeen nodules that were found to be microfollicular at fine-needle aspiration cytologic analysis and micromacrofollicular at aspiration needle biopsy were excised and the postoperative result was benign in all cases. Twenty-five nodules diagnosed as microfollicular either on both fine-needle aspiration and aspiration needle biopsy were excised and the postoperative diagnoses were benign (20 nodules) or malignant (5 nodules). These data indicate that aspiration needle biopsy can be used for preoperative selection of the nodules that are microfollicular at fine-needle aspiration by identifying the nodules with high probability of being malignant and thus contributing to the reduction in the number of surgical operations for benign nodules.

Characterization of soluble hepatitis C virus RNA-dependent RNA polymerase expressed in Escherichia coli

Production of soluble full-length nonstructural protein 5B (NS5B) of hepatitis C virus (HCV) has been shown to be problematic and requires the addition of salts, glycerol, and detergents. In an effort to improve the solubility of NS5B, the hydrophobic C terminus containing 21 amino acids was removed, yielding a truncated NS5B (NS5BDeltaCT) which is highly soluble and monodispersed in the absence of detergents. Fine deletional analysis of this region revealed that a four-leucine motif (LLLL) in the hydrophobic domain is responsible for the solubility profile of the full-length NS5B. Enzymatic characterization revealed that the RNA-dependent RNA polymerase (RdRp) activity of this truncated NS5B was comparable to those reported previously by others. For optimal enzyme activity, divalent manganese ions (Mn2+) are preferred rather than magnesium ions (Mg2+), whereas zinc ions (Zn2+) inhibit the RdRp activity. Gliotoxin, a known poliovirus 3D RdRp inhibitor, inhibited HCV NS5B RdRp in a dose-dependent manner. Kinetic analysis revealed that HCV NS5B has a rather low processivity compared to those of other known polymerases.