Tachykinins, new players in the control of reproduction and food intake: A comparative review in mammals and teleosts

In vertebrates, the tachykinin system includes tachykinin genes, which encode one or two peptides each, and tachykinin receptors. The complexity of this system is reinforced by the massive conservation of gene duplicates after the whole-genome duplication events that occurred in vertebrates and furthermore in teleosts. Added to this, the expression of the tachykinin system is more widespread than first thought, being found beyond the brain and gut. The discovery of the co-expression of neurokinin B, encoded by the tachykinin 3 gene, and kisspeptin/dynorphin in neurons involved in the generation of GnRH pulse, in mammals, put a spotlight on the tachykinin system in vertebrate reproductive physiology. As food intake and reproduction are linked processes, and considering that hypothalamic hormones classically involved in the control of reproduction are reported to regulate also appetite and energy homeostasis, it is of interest to look at the potential involvement of tachykinins in these two major physiological functions. The purpose of this review is thus to provide first a general overview of the tachykinin system in mammals and teleosts, before giving a state of the art on the different levels of action of tachykinins in the control of reproduction and food intake. This work has been conducted with a comparative point of view, highlighting the major similarities and differences of tachykinin systems and actions between mammals and teleosts.

Nonlinear effects of environmental salinity on the gill transcriptome versus proteome of Oreochromis niloticus modulate epithelial cell turnover

A data-independent acquisition (DIA) assay library for targeted quantitation of thousands of Oreochromis niloticus gill proteins using a label- and gel-free workflow was generated and used to compare protein and mRNA abundances. This approach generated complimentary rather than redundant data for 1899 unique genes in gills of tilapia acclimated to freshwater and brackish water. Functional enrichment analyses identified mitochondrial energy metabolism, serine protease and immunity-related functions, and cytoskeleton/ extracellular matrix organization as major processes controlled by salinity in O. niloticus gills. Non-linearity in salinity-dependent transcriptome versus proteome regulation was revealed for specific functional groups of genes. The relationship was more linear for other molecular functions/ cellular processes, suggesting that the salinity-dependent regulation of O. niloticus gill function relies on post-transcriptional mechanisms for some functions/ processes more than others. This integrative systems biology approach can be adopted for other tissues and organisms to study cellular dynamics for many changing ecological contexts.

A data-independent acquisition (DIA) assay library for quantitation of environmental effects on the kidney proteome of Oreochromis niloticus

Interactions of organisms with their environment are complex and environmental regulation at different levels of biological organization is often nonlinear. Therefore, the genotype to phenotype continuum requires study at multiple levels of organization. While studies of transcriptome regulation are now common for many species, quantitative studies of environmental effects on proteomes are needed. Here we report the generation of a data-independent acquisition (DIA) assay library that enables simultaneous targeted proteomics of thousands of Oreochromis niloticus kidney proteins using a label- and gel-free workflow that is well suited for ecologically relevant field samples. We demonstrate the usefulness of this DIA assay library by discerning environmental effects on the kidney proteome of O. niloticus. Moreover, we demonstrate that the DIA assay library approach generates data that are complimentary rather than redundant to transcriptomic data. Transcript and protein abundance differences in kidneys of tilapia acclimated to freshwater and brackish water (25 g/kg) were correlated for 2114 unique genes. A high degree of non-linearity in salinity-dependent regulation of transcriptomes and proteomes was revealed suggesting that the regulation of O. niloticus renal function by environmental salinity relies heavily on post-transcriptional mechanisms. The application of functional enrichment analyses using STRING and KEGG to DIA assay data sets is demonstrated by identifying myo-inositol metabolism, antioxidant and xenobiotic functions, and signalling mechanisms as key elements controlled by salinity in tilapia kidneys. The DIA assay library resource presented here can be adopted for other tissues and other organisms to study proteome dynamics during changing ecological contexts.

Chronic rhinosinusitis is associated with prolonged SARS-CoV-2 RNA shedding in upper respiratory tract samples: A case-control study

BACKGROUND

SARS-CoV-2, the COVID-19 causative agent, has infected millions of people and killed over 1.6 million worldwide. A small percentage of cases persist with prolonged positive RT-PCR on nasopharyngeal swabs. The aim of this study was to determine risk factors for prolonged viral shedding amongst patient's basal clinical conditions.

METHODS

We have evaluated all 513 patients attended in our hospital between 1 March and 1 July. We have selected all 18 patients with prolonged viral shedding and compared them with 36 sex-matched randomly selected controls. Demographic, treatment and clinical data were systematically collected.

RESULTS

Global median duration of viral clearance was 25.5 days (n = 54; IQR, 22-39.3 days), 48.5 days in cases (IQR 38.7-54.9 days) and 23 days in controls (IQR 20.2-25.7), respectively. There were not observed differences in demographic, symptoms or treatment data between groups. Chronic rhinosinusitis and atopy were more common in patients with prolonged viral shedding (67%) compared with controls (11% and 25% respectively) (P < 0.001 and P = 0.003). The use of inhaled corticosteroids was also more frequent in case group (P = 0.007). Multivariate analysis indicated that CRS (odds ratio [OR], 18.78; 95% confidence interval [95%CI], 3.89-90.59; P < 0.001) was independently associated with prolonged SARS-CoV-2 RNA shedding in URT samples, after adjusting for initial PCR Ct values.

CONCLUSION

We found that chronic rhinosinusitis and atopy might be associated with increased risk of prolonged viral shedding. If confirmed in prospective trials, this finding might have clinical implications for quarantine duration due to increased risk of pandemic spread.

Gonadotropin-inhibitory hormone in teleosts: New insights from a basal representative, the eel

Since its discovery in birds, gonadotropin-inhibitory hormone (GnIH) has triggered investigation in the other groups of vertebrates. In the present study, we have identified a single gnih gene in the European eel (Anguilla anguilla), a representative species of a basal group of teleosts (Elopomorphs). We have also retrieved a single gnih gene in Osteoglossomorphs, as well as in more recently emerged teleosts, Clupeocephala. Phylogeny and synteny analyses allowed us to infer that one of the two gnih paralogs emerged from the teleost-specific whole genome duplication (TWGD or 3R), would have been lost shortly after the 3R, before the emergence of the basal groups of teleosts. This led to the presence of a single gnih in extant teleosts as in other vertebrates. Two gnih paralogs were still found in some teleost species, such as in salmonids, but resulting from the additional whole genome duplication that specifically occurred in this lineage (4R). Eel gnih was mostly expressed in the diencephalon part of the brain, as analyzed by quantitative real-time PCR. Cloning of eel gnih cDNA confirmed that the sequence of the GnIH precursor encoded three putative mature GnIH peptides (aaGnIH-1, aaGnIH-2 and aaGnIH-3), which were synthesized and tested for their direct effects on eel pituitary cells in vitro. Eel GnIH peptides inhibited the expression of gonadotropin subunits (lhβ, fshβ, and common a-subunit) as well as of GnRH receptor (gnrh-r2), with no effect on tshβ and gh expression. The inhibitory effect of GnIH peptides on gonadotropic function in a basal teleost is in agreement with an ancestral inhibitory role of GnIH in the neuroendocrine control of reproduction in vertebrates.

Quasi One-Dimensional Metal-Semiconductor Heterostructures

The band offsets occurring at the abrupt heterointerfaces of suitable material combinations offer a powerful design tool for high performance or even new kinds of devices. Because of a large variety of applications for metal-semiconductor heterostructures and the promise of low-dimensional systems to present exceptional device characteristics, nanowire heterostructures gained particular interest over the past decade. However, compared to those achieved by mature two-dimensional processing techniques, quasi one-dimensional (1D) heterostructures often suffer from low interface and crystalline quality. For the GaAs-Au system, we demonstrate exemplarily a new approach to generate epitaxial and single crystalline metal-semiconductor nanowire heterostructures with atomically sharp interfaces using standard semiconductor processing techniques. Spatially resolved Raman measurements exclude any significant strain at the lattice mismatched metal-semiconductor heterojunction. On the basis of experimental results and simulation work, a novel self-assembled mechanism is demonstrated which yields one-step reconfiguration of a semiconductor-metal core-shell nanowire to a quasi 1D axially stacked heterostructure via flash lamp annealing. Transmission electron microscopy imaging and electrical characterization confirm the high interface quality resulting in the lowest Schottky barrier for the GaAs-Au system reported to date. Without limiting the generality, this novel approach will open up new opportunities in the syntheses of other metal-semiconductor nanowire heterostructures and thus facilitate the research of high-quality interfaces in metal-semiconductor nanocontacts.

An analysis of adaptations to multi-level intervention strategies to enhance implementation of clinical practice guidelines for treating tobacco use in dental care settings

Introduction

Our team conducted a cluster randomized controlled trial (DUET) that compared the effectiveness of three theory-driven, implementation strategies on dental provider adherence to tobacco dependence treatment guidelines (TDT). In this paper we describe the process of adapting the implementation strategies to the local context of participating dental public health clinics in New York City.

Methods

Eighteen dental clinics were randomized to one of three study arms testing several implementation strategies: Current Best Practices (CBP) (i.e. staff training, clinical reminder system and Quitline referral system); CBP + Performance Feedback (PF) (i.e. feedback reports on provider delivery of TDT); and CBP + PF + Pay-for-Performance (i.e. financial incentives for provision of TDT). Through an iterative process, we used Stirman's modification framework to classify, code and analyze modifications made to the implementation strategies.

Results

We identified examples of six of Stirman's twelve content modification categories and two of the four context modification categories. Content modifications were classified as: tailoring, tweaking or refining (49.8%), adding elements (14.1%), departing from the intervention (9.3%), loosening structure (4.4%), lengthening and extending (4.4%) and substituting elements (4.4%). Context modifications were classified as those related to personnel (7.9%) and to the format/channel (8.8%) of the intervention delivery. Common factors associated with adaptations that arose during the intervention included staff changes, time constraints, changes in leadership preferences and functional limitations of to the Electronic Dental Record.

Conclusions

This study offers guidance on how to capture intervention adaptation in the context of a multi-level intervention aimed at implementing sustainable changes to optimize TDT in varying public health dental settings.

Tachykinin-3 Genes and Peptides Characterized in a Basal Teleost, the European Eel: Evolutionary Perspective and Pituitary Role

In mammals, neurokinin B (NKB) is a short peptide encoded by the gene tac3. It is involved in the brain control of reproduction by stimulating gonadotropin-releasing hormone (GnRH) neurons, mainly via kisspeptin. We investigated tac3 genes and peptides in a basal teleost, the European eel, which shows an atypical blockade of the sexual maturation at a prepubertal stage. Two tac3 paralogous genes (tac3a and tac3b) were identified in the eel genome, each encoding two peptides (NKBa or b and NKB-related peptide NKB-RPa or b). Amino acid sequence of eel NKBa is identical to human NKB, and the three others are novel peptide sequences. The four eel peptides present the characteristic C-terminal tachykinin sequence, as well as a similar alpha helix 3D structure. Tac3 genes were identified in silico in 52 species of vertebrates, and a phylogeny analysis was performed on the predicted TAC3 pre-pro-peptide sequences. A synteny analysis was also done to further assess the evolutionary history of tac3 genes. Duplicated tac3 genes in teleosts likely result from the teleost-specific whole genome duplication (3R). Among teleosts, TAC3b precursor sequences are more divergent than TAC3a, and a loss of tac3b gene would have even occurred in some teleost lineages. NKB-RP peptide, encoded beside NKB by tac3 gene in actinopterygians and basal sarcopterygians, would have been lost in ancestral amniotes. Tissue distribution of eel tac3a and tac3b mRNAs showed major expression of both transcripts in the brain especially in the diencephalon, as analyzed by specific qPCRs. Human NKB has been tested in vitro on primary culture of eel pituitary cells. Human NKB dose-dependently inhibited the expression of lhβ, while having no effect on other glycoprotein hormone subunits (fshβ, tshβ, and gpα) nor on gh. Human NKB also dose-dependently inhibited the expression of GnRH receptor (gnrh-r2). The four eel peptides have been synthesized and also tested in vitro. They all inhibited the expression of both lhβ and of gnrh-r2. This reveals a potential dual inhibitory role of the four peptides encoded by the two tac3 genes in eel reproduction, exerted at the pituitary level on both luteinizing hormone and GnRH receptor.

Dietary Mannan Oligosaccharides: Counteracting the Side Effects of Soybean Meal Oil Inclusion on European Sea Bass (Dicentrarchus labrax) Gut Health and Skin Mucosa Mucus Production?

The main objective of this study was to assess the effects of 4 g kg(-1) dietary mannan oligosaccharides (MOS) inclusion in soybean oil (SBO)- and fish oil (FO)-based diets on the gut health and skin mucosa mucus production of European sea bass juveniles after 8 weeks of feeding. Dietary MOS, regardless of the oil source, promoted growth. The intestinal somatic index was not affected, however dietary SBO reduced the intestinal fold length, while dietary MOS increased it. The dietary oil source fed produced changes on the posterior intestine fatty acid profiles irrespective of MOS dietary supplementation. SBO down-regulated the gene expression of TCRβ, COX2, IL-1β, TNFα, IL-8, IL-6, IL-10, TGFβ, and Ig and up-regulated MHCII. MOS supplementation up-regulated the expression of MHCI, CD4, COX2, TNFα, and Ig when included in FO-based diets. However, there was a minor up-regulating effect on these genes when MOS was supplemented in the SBO-based diet. Both dietary oil sources and MOS affected mean mucous cell areas within the posterior gut, however the addition of MOS to a SBO diet increased the mucous cell size over the values shown in FO fed fish. Dietary SBO also trends to reduce mucous cell density in the anterior gut relative to FO, suggesting a lower overall mucosal secretion. There are no effects of dietary oil or MOS in the skin mucosal patterns. Complete replacement of FO by SBO, modified the gut fatty acid profile, altered posterior gut-associated immune system (GALT)-related gene expression and gut mucous cells patterns, induced shorter intestinal folds and tended to reduce European sea bass growth. However, when combined with MOS, the harmful effects of SBO appear to be partially balanced by moderating the down-regulation of certain GALT-related genes involved in the functioning of gut mucous barrier and increasing posterior gut mucous cell diffusion rates, thus helping to preserve immune homeostasis. This denotes the importance of a balanced dietary n-3/n-6 ratio for an appropriate GALT-immune response against MOS in European sea bass juveniles.

Outcomes of hospitalisation for right heart failure in pulmonary arterial hypertension

The aim of this study was to examine the causes and outcomes of hospitalisation in patients with pulmonary arterial hypertension (PAH). 205 consecutive hospitalisations occurring between 2000 and 2009 in 90 PAH patients were studied. The leading causes for hospitalisation were right heart failure (RHF; 56%), infection (16%) and bleeding disorders (8%). For patients with RHF, in-hospital mortality was 14% overall, 46% for patients receiving inotropes and 48% for those admitted to the intensive care unit. The predictors for in-hospital mortality were the presence of connective tissue disease (CTD) (OR 4.92), systolic blood pressure <100 mmHg (OR 4.32) and Na ≤ 136 mEq · L(-1) (OR 4.29). Mortality after discharge was 13, 26 and 35% at 3, 6 and 12 months, respectively. World Health Organization functional class prior to admission, renal dysfunction, Charlson comorbidity index, and the presence of CTD were all predictors of mortality after discharge. Hyponatraemia and low systolic blood pressure upon admission and underlying CTD are the main prognostic factors for in-hospital mortality in patients with PAH admitted for RHF. The short-term outcomes after discharge are poor and remarkably worse in patients with underlying CTD or renal impairment. Early recognition of these factors may guide decisions regarding more aggressive therapy, including consideration for lung transplantation.

Usefulness of Video-EEG monitoring in patients with drug-resistant epilepsy

OBJECTIVE

To evaluate the characteristics of patients on whom long-term Video-EEG monitoring is performed in a specialist centre and to assess its suitability to study refractory epilepsy patients.

METHODS

A prospective analysis and study of Video-EEG monitoring was performed in a series of 100 refractory epilepsy patients from a single centre. The analysis included demographic data, the time until the first seizure, the methods used to provoke seizures, and the outcome (usefulness, change in the management, pharmacological and surgical improvement). A subgroup analysis based on diagnosis was performed.

RESULTS

The study was performed mainly on young people (mean 34.4 years) and the first seizure appeared in a mean of 30hours, requiring most of the patients to withdraw the medication. Nevertheless, there were no cases of status epilepticus. The usefulness of the test was high in all the groups. The management was changed in 65% of the patients with pharmacological and surgical improvement.

CONCLUSION

Long-term Video-EEG monitoring is a suitable test to study refractory epilepsy patients. The main problem in our country is accesibility.

Life Expectancy of Women with Lupus Nephritis Now Approaches That of the General Population

Immunosuppressive treatment has changed the prognosis of Lupus nephritis over time, but improvement in prognosis is difficult to analyze in different historical periods, and should be better demonstrated in comparison with life expectancy of sex-and age-matched people. Long-term patient and renal survival of 90 patients diagnosed with Lupus nephritis at our center from 1968 to 2001 with a follow-up time of 14±8 years was retrospectively evaluated. Patient and kidney survival significantly increased over time. Multivariate analyses show that risks of patient and renal death decreased by 8% at each year of follow-up, and increased by more than 5 time in patients aged > 30 years at diagnosis. As only 14 patients were men, relative survival as compared to that of the sex- and age-matched general population of the Piedmont Region was calculated for the 76 women. Improvement in the survival of the cohort of women was seen at any time of follow-up: in particular, it was sharply lower in the first period (relative survival at 5,10 and 15 years = 0.784, 0.665, and 0.620, respectively) and increased in the second (relative survival at 5,10 and 15 years = 0.939, 0.921, and 0.850, respectively) nearly approaching that expected for the general population, i.e. 0.993, 0.983 and 0.967, respectively. Taken together, our data allow us to draw the conclusion that life expectancy in women with Lupus nephritis has improved over time, paralleling an improved awareness of the disease and a significant increase in steroid pulse therapy as induction/remission phase. Improvement in survival is for the first time demonstrated to cover the gap with life expectancy of the general population for women with Lupus nephritis.

Disproportionate elevation of N-terminal pro-brain natriuretic peptide in scleroderma-related pulmonary hypertension

N-terminal pro-brain natriuretic peptide (NT-proBNP) is a marker of neurohormonal activation that is useful in the diagnosis and prognosis of various forms of pulmonary arterial hypertension (PAH). We sought to characterise and compare NT-proBNP in a cohort of PAH related to systemic sclerosis (PAH-SSc) and idiopathic PAH (IPAH) patients. NT-proBNP levels, collected from PAH-SSc and IPAH patients followed prospectively, were compared and correlated with haemodynamic variables. Cox proportional hazard models were created to assess the predictive value of NT-proBNP. 98 patients (55 PAH-SSc, 43 IPAH) were included. Haemodynamics were similar, except for lower mean pulmonary arterial pressure in PAH-SSc. NT-proBNP levels were significantly higher in PAH-SSc (3,419+/-3,784 versus 1,393+/-1,633 pg x mL(-1); p<0.01) and were more closely related to haemodynamics in PAH-SSc than IPAH. 28 patients died. NT-proBNP predicted survival (hazard ratio (HR) 3.18; p<0.01) in the overall cohort; however, when stratified by group, predicted survival only in PAH-SSc (HR 3.07, p<0.01 versus 2.02, p = 0.29 in IPAH). This is the first description showing NT-proBNP levels are 1) significantly higher in PAH-SSc than IPAH despite less severe haemodynamic perturbations, and 2) stronger predictors of survival in PAH-SSc, suggesting that neurohormonal regulation may differ between PAH-SSc and IPAH. Future studies to define pertinent mechanisms are warranted.

Improvement in Relative Survival of Patients with Vasculitis: Study of 101 Cases Compared to the General Population

Immunosuppressive treatment has changed the prognosis of renal vasculitis over time, but improvement in prognosis is difficult to analyze in different historical periods, and can be better demonstrated by comparison with life expectancy of sex- and age-matched people. Long-term survival of 101 patients diagnosed with systemic vasculitis at our center from 1975 to 2002 was retrospectively evaluated in comparison with that of the Region's age- and sex-matched population. Patient and kidney survival significantly increased over time. Multivariate analyses showed that risks of patient and renal death decreased by 10% and 7%, respectively, at each year of follow-up, and increased by 6.3% and 5.2% for each year of age. Relative survival significantly improved over time, approaching that of the general population for cases diagnosed after 1993, mainly in women <60 years (from 0.671 at 5-years in the first period to 0.916 in the last period), while 5-year-relative-survival was still 0.530 and 0.682 in men and women > 60 years, respectively. Poisson-based multinomial analyses confirmed the significant risk of the first periods of diagnosis and of dialysis in worsening of the relative survival of patients compared to that of the general population. Life expectancy in patients with renal vasculitis has improved over time, paralleling a significant increase in steroid pulse/cyclophosphamide association therapy and an earlier diagnosis due to the introduction of the ANCA test. Relative survival has considerably improved, and now approaches that expected in the general population for women, but not for men.

[Complement activation products (C3a and C5b-9) as markers of activity of dermatomyositis. Comparison with usual biochemical parameters]

INTRODUCTION

Dermatomyositis (DM) is an autoimmune disease included in the group of idiopathic inflammatory myopathies. Markers of disease activity are needed for clinical control in order to facilitate adjustment of immunomodulatory therapy. We analyzed the relationship between complement activation products (CAP) and the activity of dermatomyositis and its usefulness in the follow-up of the disease and the prediction of recrudescences related to usual biochemical parameters.

MATERIAL AND METHODS

We studied 16 patients with DM that were followed periodically. In each appointment the degree of cutaneous and muscular activity was assessed and such disease activity was correlated with plasma levels of C3a and C5b-9, measured by ELISA.

RESULTS

Though we obtained certain correlation between disease activity and plasma levels of C3a and C5b-9, the strength of such correlation was not superior to that obtained by usual biochemical markers. C3a was shown to be the most sensitive marker (100 %) with a sufficient specificity (83.3 %) in the capability to predict recrudescences.

CONCLUSIONS

C3a and, to a lesser extent C5b-9, would be useful in the identification of patients with especially active DM as well as in predicting disease recrudescences. Nevertheless they are not superior to the rest of biochemical markers as indicators of current activity.

Factors determining early adherence to a lung cancer screening protocol

Lung cancer screening using computed tomography (CT) is effective in detecting early stage disease. However, concerns regarding adherence have been raised. The current authors conducted a retrospective observational study of 641 asymptomatic smokers enrolled in a lung cancer screening programme between 2000 and 2003. Adherent subjects were compared with nonadherent subjects with regard to lung function, sex, age, motivation for enrollment, smoking status, distance to the referral centre, family history of lung cancer, asbestos exposure, education, the presence and type of nodule(s) seen on initial CT, and exposure to a nursing intervention designed to improve adherence. Overall, early adherence to the study protocol was 65%. Multivariate analysis confirmed the importance of sex, proximity to the referral centre, the presence of noncalcified nodules, and the nursing intervention as factors conditioning adherence to the study protocol. Patients encouraged to participate in the study were more adherent, as were former smokers. Sex interactions were observed in multivariate analysis. The nursing intervention was significant for females, while abnormal lung function improved male adherence. Adherence to lung cancer screening is particularly good among females and subjects living near the referral centre. The present study suggests the need to develop new strategies, especially those targeting males and subjects with low risk perception, in order to improve adherence.

Hyperleptinaemia, respiratory drive and hypercapnic response in obese patients

Leptin is a powerful stimulant of ventilation in rodents. In humans, resistance to leptin has been consistently associated with obesity. Raised leptin levels have been reported in subjects with sleep apnoea or obesity-hypoventilation syndrome. The aim of the present study was to assess, by multivariate analysis, the possible association between respiratory centre impairment and levels of serum leptin. In total, 364 obese subjects (body mass index >or=30 kg.m(-2)) underwent the following tests: sleep studies, respiratory function tests, baseline and hypercapnic response (mouth occlusion pressure (P(0.1)), minute ventilation), fasting leptin levels, body composition and anthropometric measures. Subjects with airways obstruction on spirometry were excluded. Out of the 346 subjects undergoing testing, 245 were included in the current analysis. Lung volumes, age, log leptin levels, end-tidal carbon dioxide tension, percentage body fat and minimal nocturnal saturation were predictors for baseline P(0.1). The hypercapnic response test was performed by 186 subjects; log leptin levels were predictors for hypercapnic response in males, but not in females. Hyperleptinaemia is associated with a reduction in respiratory drive and hypercapnic response, irrespective of the amount of body fat. These data suggest the extension of leptin resistance to the respiratory centre.

Development of a magnetic capture hybridization-PCR assay for Listeria monocytogenes direct detection in milk samples

AIMS

A rapid and sensitive method for Listeria monocytogenes direct detection from milk was developed. It is based on a magnetic capture hybridization procedure for selective DNA purification, followed by PCR identification. A comparison with two similar commercial systems from Dynal (Dynabeads) was carried out.

METHODS AND RESULTS

The technique used previously developed nanoparticles modified with a 21-mer oligonucleotide. This sequence, sharing homology with all the L. monocytogenes strains, was selected on hlyA gene and located outside the desired specific PCR site to avoid cross-contaminations. Capture probe properties, in term of spacer length and purification, were determined to obtain the highest hybridization efficiency. Its specificity was tested in hybridization experiments with nontarget bacterial species. Any inhibitory effect of the nanoparticles on PCR was also examined. The amplification performed with the purified DNA could reliably identify a 10 CFU ml(-1) contamination rate.

CONCLUSIONS

The optimized purification method showed a high specificity and sensitivity, with a detection level one log more sensitive than PCR carried out with nucleic acids obtained using commercial nanoparticles.

SIGNIFICANCE AND IMPACT OF THE STUDY

The method, avoiding pre-enrichment, provides a rapid alternative to conventional microbiological detection methods. Furthermore, it is suitable for automation and can be proposed for the screening of a large number of samples.

[Homocysteine, folate therapy and outcome in hemodialysis: results from a prospective study]

BACKGROUND

Despite the well-known effectiveness of folate therapy on hyperhomocysteinemia in hemodialysis, its benefits on outcome are still unclear.

METHODS

Sixty-five patients on thrice-weekly maintenance hemodialysis lasting more than 3 months were followed up for 1 year after stratification by predialysis homocysteine level (tHcy). Parenteral folate (25 mg quarterly) and cobalamine (1 mg quarterly) therapy was started only if the tHcy levels were > 30 uM/L at baseline or at scheduled retests (every 7 months). End points were overall mortality and new ischemic events (affecting heart, brain, or lower extremities).

RESULTS

58.5% of patients received treatment at baseline and achieved a 60% reduction of tHcy. 38.1% progressed to levels of over 30 tHcy at 6 months and were placed on treatment. No other major changes occurred until the end of the study. An excess of both overall mortality (30.8% versus 12.1%; p = 0.075) and vascular morbidity (38.5% versus 12.1%; p = 0.03) occurred in initially untreated patients,those presenting without baseline intermediate to severe hyperhomocysteinemia.

CONCLUSIONS

In undertaking hemodialysis, it appears that treating intermediate to severe hyperhomocysteinemia carries better prognosis for outcome than untreated moderate or absent hyperhomocysteinemia. It is uncertain if the benefit of therapy is valid, or if it is confounded by an association between lower tHhy and hidden malnutrition or concomitant diseases.

[Metabolic effects of changes in dietary sodium intake in patients with essential hypertension]

BACKGROUND

To evaluate the metabolic effects of modification of sodium intake in patients with essential hypertension.

METHODS

Thirteen patients with essential hypertension (10 M, median age 51 yrs, range 21-64) followed in random order a low-sodium and a high-sodium diet (50 mmol Na/day vs 250 mmol/day for two weeks each). At the end of each diet an evaluation was made of 24 hour blood pressure (ABPM, Spacelabs 90207) and serum concentration of: glucose, total and HDL cholesterol, uric acid, lipoproteins A, B, Lp(a), total proteins, albumin.

RESULTS

Twenty-four hours systolic and diastolic BP were significantly higher at the end of high sodium diet than of low sodium diet [respectively 132 mmHg (120-161) vs 128 mmHg (109-150); p = 0.008 and 84 mmHg (71-99) vs 81 mmHg (70-95); p = 0.008)]. No significant variations were found as regards serum glucose and lipidic parameters between low and high sodium diets. Serum uric acid was significantly higher following low sodium diet [5.9 mg/dl (4.5-8) vs 4.6 mg/dl (3.4-6.5); p = 0.003)], as well as serum total proteins [7.2 g/dl (6.9-8.2) vs 7 g/dl (6.5-7.8); p = 0.027)]. A significant direct correlation was found between changes of uric acid and total proteins from low to high sodium diet (Spearman's rho = 0.57; p = 0.04).

CONCLUSIONS

In patients with essential hypertension a moderate dietary sodium restriction, able to reduce significantly 24 hours arterial pressure, does not worsen serum glucose nor lipids concentration.

[Asthma emergencies: can we lower the rate of readmission after discharge?]

INTRODUCTION

The rate of readmission among asthmatic emergency patients varies. In 1991 we observed a 9% rate of readmission following emergency room release. Studies of the number of readmissions or request for medical care are used as the basis for recommendations for releasing patients from hospital emergency care. No studies have assessed disease stability following release or factors related to stability.

OBJECTIVES

To assess the course of disease and clinical stability of patients in the period immediately following release from emergency room care. To determine factors that might predict such stability. to determine the rate of readmission in the month following release after applying a treatment protocol and release criteria, with follow-up examination 72 h later.

MATERIAL AND METHODS

Prospective, descriptive study with follow-up 72 h and one month after release.

SETTING

Emergency and pneumology departments of a general hospital.

PERIOD

six months.

PATIENTS

82 asthmatic patients released from the emergency room.

RESULTS

Two patients (2.43% were readmitted. At the first follow-up visit (72 h) 81 patients (98.78%) were seen. At the second visit, 66 patients (80.5%) were examined. We observed stability in 70.3% of patients at 72 h and in 86.4% after on month. Stability was statistically related to whether peak expiratory flow greater or less than 70% (76.92% stable versus 46.66% unstable) (p < 0.05). No other clinical, epidemiological or treatment variables recorded upon release were found to influence stability.

CONCLUSIONS

1) A large proportion of patients are in stable condition 72 h after release. 2) When peak expiratory flow upon release is > 70%, stability is significantly increased 72 h later. 3) Our 2.43% rate of readmission one month after release is very low. 4) No differences in stability were seen to be related to oral corticoid prescription upon release.

[Mediastinal liposarcoma. A report of 2 cases]

Liposarcomas are malignant mesenchymal tumors whose primary location in the mediastinum is rare. We report two cases of mediastinal liposarcoma, describing the clinical signs and radiologic features found and the diagnostic procedures performed. The significance of histologic variability as a factor that conditions treatment and prognosis is underlined.

[Correlations between viral serology and different clinical characteristics in patients with lupus nephropathy]

BACKGROUND

Relationships between viral infections and autoimmune diseases are complex and debated: on the one hand, patients with LES are particularly prone to develop viral infections, on the other, some virus are thought to play a role both in triggering the onset of the immunologic disease and in conferring peculiar clinical features to flare-ups.

METHODS

This study has drawn an epidemiologic profile of viral pathology from Epstein Barr virus, Parvovirus B 19 and Cytomegalovirus in 60 patients with LES followed-up for a period ranging from 13 to 340 months (on average 158 months).

RESULTS

Cytomegalovirus seropositivity has turned out to be a strong, statistically significant risk factor for vascular accidents and especially for peripheral ones, such as Raynaud phenomenon, ulcers and distal necrosis (OR = 6.5 IC = 0.7-7.9* p = 0.037).

CONCLUSIONS

Although Cytomegalovirus seropositivity is associated with an increased frequency of LAC/ACA, its relationship with vascular events does not seem to be mediated through such antibodies, apparently acting as an independent risk factor which also works in LAC/ACA negative patients. Parvovirus B 19 seropositivity has turned out to be the only increased risk factor for the development of anemia, although not reaching statistical significance, whereas Epstein Barr seropositivity does not appear to influence clinical features significantly.

Exercise ultrafast computed tomography for the detection of coronary artery disease

Ultrafast computed tomography permits the assessment of global and regional left ventricular function during exercise. To evaluate the feasibility of using this new technique for the diagnosis of coronary artery disease, 27 patients undergoing cardiac catheterization for diagnosis of chest pain were evaluated. Fifteen patients had significant (greater than 50%) coronary artery stenosis by quantitative coronary angiography. One vessel disease was found in 12 patients and multivessel disease in 3. Fourteen (93%) of the 15 patients with significant coronary stenosis had a decrease in ultrafast computed tomographic ejection fraction during exercise from (mean +/- SD) 65 +/- 7% to 60 +/- 7% (p less than 0.001). The tomographic ejection fraction increased greater than 5% units during exercise in 10 (83%) of the 12 patients with normal coronary arteries. The mean tomographic ejection fraction in this group was 68 +/- 6% at rest and 75 +/- 6% at peak exercise (p less than 0.001). Regional wall motion was quantified by analyzing the segmental ejection fraction of 12 30 degree pie segments at each tomographic level of the left ventricle. A new regional wall motion abnormality developed during exercise in 12 (86%) of 14 patients with coronary artery disease; one patient was excluded because of a technical problem in data storage. Eleven (93%) of the 12 patients with normal coronary arteries had normal wall motion during exercise. In no patient with ischemic heart disease were both variables, ejection fraction response and regional wall motion, normal. Exercise ultrafast computed tomography appears to be a useful technique for the evaluation of coronary artery disease in patients with chest pain and predominant single vessel coronary artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Severity of coronary artery disease among blacks with acute myocardial infarction

A growing body of evidence suggests that survival after acute myocardial infarction (AMI) is considerably worse among blacks than whites. The severity of coronary artery disease (CAD), as measured by the number of diseased vessels and the degree of left ventricular dysfunction, is the major determinant of survival after AMI. To determine whether or not the severity of CAD could explain the poor prognosis in a cohort of blacks followed at this institution, cardiac catheterization was performed in a consecutive series of 51 patients less than 70 years of age. All patients were studied within 2 weeks after AMI. The mean age of the patients was 56 +/- 8 (mean +/- standard deviation) and 71% were men. A greater than or equal to 50 narrowing in 0, 1, 2 or 3 coronary arteries was noted in 5, 24, 40 and 31%, respectively. Left main stenosis was present in 3 patients (6%) and the mean left ventricular ejection fraction was 55%. In a subgroup of 20 patients echocardiographic estimates of left ventricular mass/height yielded a mean of 196 g/m, and left ventricular hypertrophy on echocardiogram was present in 74%. These data indicate that among blacks with AMI in this series CAD was only modestly more severe than expected and suggest that other factors most likely explain the high mortality in blacks after hospital discharge.

Coronary artery disease in blacks of lower socioeconomic status: angiographic findings from the Cook County Hospital Heart Disease Registry

During a 4-year period, 1,022 blacks underwent angiography at our institution for the presumptive diagnosis of coronary artery disease (CAD). Among the 454 men, at least one coronary stenosis was demonstrated in 288 cases (63%), while significant narrowing was found in 242 of 568 women (43%). Despite the frequent finding of normal coronary arteries, those patients with significant CAD had severe disease. Thus among men with CAD, left main stenosis was present in 7% and three-vessel narrowing was seen in 53%; among the women, 8% had left main stenosis and three-vessel disease was present in 52%. Two countervailing processes appear to be occurring, namely (1) identification of true coronary symptoms is difficult in this group of patients and (2) diagnosis of true cases occurs late in the course of the disease and the distribution of the number of vessels involved is skewed upwards. Increased echocardiographically determined left ventricular mass and hypertension were prevalent among all groups. These data suggest that the approach to the diagnosis of CAD in the black population is difficult and severe CAD occurs frequently.

Impairment in auditory and visual function follows perinatal viral infection in the rat

Acoustic startle reflexes are elicited by intense tone bursts but inhibited if weak bursts precede reflex elicitation. Rats were infected by intracerebral inoculation with lymphocytic choriomeningitis virus (LCMV) at birth. Compared to control animals, infected animals had higher elicitation and inhibition thresholds and showed recruitment at intense stimulus levels. Histopathology revealed both cochlear and retinal degeneration. Like some infectious agents in humans, perinatal exposure to LCMV in the rat yields a severe polysensory neuropathy.

Runaway pacemaker

We report a case of a runaway cardiac pacemaker in a hemodynamically unstable patient requiring surgical intervention for correction of the malfunction. The technique for gaining rapid access to the permanent pacemaker and disarming it, and for the utilization of a portable pacemaker generator to establish a normal heart rate is presented.