Diagnosis and outcome of patients with idiopathic pleural effusions.

INTRODUCTION: Long-term follow-up course for patients with idiopathic pleural effusions has not been established. METHODS: From October 2013 to June 2021 all patients with idiopathic effusion were prospectively followed up with clinical examination and imaging at 1, 3, 6 and every 6 months for a minimum of 1 year. RESULTS: Twenty-nine patients were diagnosed with idiopathic effusion and followed up. Mesothelioma was detected during the follow-up in two patients at 7 and 18 months, one of whom had blood-tinged pleural fluid and the other reported a 10% weight loss. Mesothelioma was not diagnosed in any of the patients with effusion covering less than two thirds of the hemithorax, and without constitutional symptoms or a blood-tinged fluid appearance. Most of the effusions resolved or showed a clear improvement in the first six months. CONCLUSION: Patients without weight loss and with small, non-hematic effusions, may benefit from conservative treatment and clinical-radiological follow-up.

Effect of liraglutide on physical performance in type 2 diabetes: Results of a randomized, double-blind, controlled trial (LIPER2).

AIMS: To assess the effect of the GLP-1 analogue liraglutide on measures of cardiac function and physical performance in patients with type 2 diabetes (T2D). METHODS: In this phase-IV randomized double-blind placebo-controlled parallel-group clinical trial at a tertiary hospital, T2D patients with HbA1c levels of 7-10% with oral agents and/or intermediate-/long-acting insulin were allocated (computer-generated randomization, ratio 1:1) to either liraglutide 1.8 mg/day or a placebo for 6 months. The primary endpoint was maximum oxygen consumption (VO2max) during cycle ergometry, while other procedures included a 6-min walk test, echocardiography, anthropometry and blood tests. Safety endpoints were also monitored, and an intention-to-treat analysis was performed. RESULTS: A total of 24 patients (15 women) aged 52 (11.7) years, with diabetes duration of 8.7 (5.8) years, BMI 34.98 (6.2) kg/m2 and HbA1c 8.2% (0.68%), were randomized to liraglutide 1.8 mg daily or placebo. There were no differences in VO2max [17.98 (4.8) vs. 15.90 (4.96) mL/kg/min; P > 0.10], VE/VCO2 slope [30.18 (4.8) vs. 32 (4.49)], left ventricular ejection fraction or 6-min walk test [530.7 (86) vs. 503.9 (84) m] at 6 months. HbA1c was lower (6.7% vs. 7.7%; P = 0.005), with a trend towards lower maximum systolic blood pressure during ergometry [171.7 (24.4) vs. 192.5 (25.6); P = 0.052] in the liraglutide group at the end of the study. There were no severe adverse events. CONCLUSION: In this trial, liraglutide improved glycaemic control in T2D, but had no significant effects on either physical performance or myocardial function.

Restricted puckering of mineralized RNA-like riboses.

The pseudorotational motions of highly hydroxylated pentafuranose sugars in the free state and tethered to hydroxyapatite have been compared. The conformation pentafuranose ring remains restricted at the North region of the pseudorotational wheel, which is the one typically observed for nucleosides and nucleotides in the double helix A-RNA, when the phosphate-bearing sugar is anchored to the mineral surface. Results indicate that the severe restrictions imposed by the mineral are responsible of the double helix preservation when DNA and RNA are encapsulated in crystalline nanorods.

Sol-gel hybrid films based on organosilane and montmorillonite for corrosion inhibition of AA2024.

The present work reports the production of films on AA2024-T3 composed of vinyltrimethoxysilane (VTMS)/tetraethylorthosilicate (TEOS) with incorporation of montmorillonite (sodium montmorillonite and montmorillonite modified with quaternary ammonium salt, abbreviated Na and 30B, respectively), generated by the sol-gel process. According to FT-IR analyses the incorporation of montmorillonite does not affect silica network. Electrochemical characterization was performed by electrochemical impedance spectroscopy measurement in 0.05 mol L(-1) NaCl solution. Results indicate that montmorillonite incorporation improves the corrosion protection compared to the non-modified system. Scanning electron microscopy micrographs reveal that high concentrations of montmorillonite provide agglomerations on the metallic surface, which is in detriment of the anticorrosive performance. The VTMS/TEOS/30B films with the lowest concentration (22 mg L(-1)) of embedded clay provide the highest corrosion protection.

Sensitive thermal transitions of nanoscale polymer samples using the bimetallic effect: application to ultra-thin polythiophene.

A sensitive nanocalorimetric technology based on microcantilever sensors is presented. The technology, which combines very short response times with very small sample consumption, uses the bimetallic effect to detect thermal transitions. Specifically, abrupt variations in the Young's modulus and the thermal expansion coefficient produced by temperature changes have been employed to detect thermodynamic transitions. The technology has been used to determine the glass transition of poly(3-thiophene methyl acetate), a soluble semiconducting polymer with different nanotechnological applications. The glass transition temperature determined using microcantilevers coated with ultra-thin films of mass = 10(-13) g is 5.2 °C higher than that obtained using a conventional differential scanning calorimeter for bulk powder samples of mass = 5 × 10(-3) g. Atomistic molecular dynamics simulations on models that represent the bulk powder and the ultra-thin films have been carried out to provide understanding and rationalization of this feature. Simulations indicate that the film-air interface plays a crucial role in films with very small thickness, affecting both the organization of the molecular chains and the response of the molecules against the temperature.

Self-assembly of a designed amyloid peptide containing the functional thienylalanine unit.

The self-assembly of a peptide based on a sequence from the amyloid beta peptide but incorporating the non-natural amino acid beta-2-thienylalanine (2-Thi) has been investigated in aqueous and methanol solutions. The peptide AAKLVFF was used as a design motif, replacing the phenylalanine residues (F) with 2-Thi units to yield (2-Thi)(2-Thi)VLKAA. The 2-Thi residues are expected to confer interesting electronic properties due to charge delocalization and pi-stacking. The peptide is shown to form beta-sheet-rich amyloid fibrils with a twisted morphology, in both water and methanol solutions at sufficiently high concentration. The formation of a self-assembling hydrogel is observed at high concentration. Detailed molecular modeling using molecular dynamics methods was performed using NOE constraints provided by 2D-NMR experiments. The conformational and charge properties of 2-Thi were modeled using quantum mechanical methods, and found to be similar to those previously reported for the beta-3-thienylalanine analogue. The molecular dynamics simulations reveal well-defined folded structures (turn-like) in dilute aqueous solution, driven by self-assembly of the hydrophobic aromatic units, with charged lysine groups exposed to water.

Differentiating between malignant and idiopathic pleural effusions: the value of diagnostic procedures.

BACKGROUND: Which diagnostic procedures should be used to differentiate between idiopathic and malignant pleural effusions, is not well established. AIM: To identify which parameters allow differentiation between idiopathic and malignant pleural effusions. DESIGN: Case-note review. METHODS: Over a 12-year period, we treated 1014 consecutive pleural effusion patients, of whom 346 were diagnosed as having an idiopathic or malignant aetiology. We analysed medical history, chest X-ray, pleural fluid analysis (biochemical, microbiological and cytological), chest CT scan and additional examinations that were used according to clinical findings, and compared them with the eventual diagnosis and outcome. RESULTS: Eighty-three patients with idiopathic effusions and 263 with malignant effusions were included. Idiopathic pleural effusion resolved in 47 patients, improved in 20 and persisted in 16. Biochemical pleural fluid analysis did not predict these outcomes. A history of neoplasm, chest X-ray and CT features, as well as additional examinations according to clinical findings, established a diagnosis or suspicion of malignancy in 256 (97.7%) of the 263 patients who received a diagnosis of malignant effusion. Diagnostic thoracoscopy was helpful in seven patients in whom malignant disease was strongly suspected, despite the absence of other pathological findings. DISCUSSION: Non-invasive complementary examinations generally allowed accurate differentiation between malignant and idiopathic effusions. Patients with idiopathic pleural effusions generally had favourable outcomes.

Factors influencing length of hospital stay in patients with bacterial pleural effusion.

BACKGROUND: Factors influencing length of hospital stay have been poorly analyzed in parapneumonic pleural effusions (PPE). OBJECTIVES: The aim of this work is to identify the variables that determine increased hospital stay in patients with infectious pleural effusion (PE). PATIENTS AND METHODS: We analyzed 112 patients with PE: empyema, complicated parapneumonic and non-complicated parapneumonic. Epidemiologic, biochemical, therapeutic and radiological variables were analyzed. Correlations with hospital stay were studied using the Student's t test, analysis of variance, Mann-Whitney U-test and linear regression model. RESULTS: Among the 112 patients studied, there were 32 empyema, 50 complicated and 30 non-complicated parapneumonic cases. The median of length stay for all patients was 17 days. Longer hospitalization was required in patients with empyemic PE (p = 0.015), patients with underlying diseases (p = 0.003), those needing pleural drainage (p = 0.005) or decortication (p = 0.043) and those presenting unfavorable radiological outcome after treatment (p = 0.02). Biochemical parameters associated with longer hospital stay were elevated pleural fluid polymorphonuclear elastase (p = 0.001, r = 0.307) and lactate dehydrogenase (p = 0.001, r = 0.312). After linear regression analysis, only underlying disease, pleural drainage and pleural fluid polymorphonuclear elastase values remained in the model, explaining 23.1% of the variability of days of hospitalization. CONCLUSIONS: The patients with PPE and empyema who required longer hospitalization were those with purulent fluid, underlying disease, surgical drainage and/or decortication, with unfavorable radiological outcome and higher pleural fluid levels of lactate dehydrogenase and polymorphonuclear elastase.

Metalloproteinases and tissue inhibitors of metalloproteinases in exudative pleural effusions.

The aim of this study was to assess the expression of several metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in exudative pleural effusions, and their relationship with inflammatory and fibrinolytic mediators in parapneumonic effusions. The study included 51 parapneumonic effusions (30 empyema or complicated parapneumonic, 21 noncomplicated parapneumonic), 28 tuberculous, 30 malignant and 30 transudates. Inflammatory markers (tumour necrosis factor-alpha, interleukin-8, polymorphonuclear elastase), fibrinolytic system variables (tissue plasminogen activator (PA), urokinase PA (u-PA), plasminogen activation inhibitor (PAI)-1, PAI-2), and several MMPs (MMP-1, MMP-2, MMP-8, MMP-9) and TIMPs (TIMP-1, TIMP-2) were determined by ELISA in plasma and pleural fluid. Elevated MMP-2 and TIMP-1 concentrations were observed in all the pleural fluid samples studied. The group of empyema or complicated parapneumonic effusions showed higher MMP-1, MMP-8 and MMP-9 concentrations than the remaining exudates. There was no correlation between MMP and TIMP levels in plasma and pleural fluid in this group of effusions. In parapneumonic effusions, MMP-1, MMP-8 and MMP-9 showed a positive correlation with the inflammatory markers and with u-PA and PAI-1. Moreover, there was a relationship between MMP-8 concentration in pleural fluid and pleural thickening at the end of treatment. In conclusion, elevated metalloproteinase-1, -8 and -9 expression was found in parapneumonic pleural effusions. These metalloproteinases could be implicated in the local inflammatory response existing in this group of effusions.

Stabilization of rasburicase and physico-chemical characterization of the resulting injectable formulation.

Rasburicase (Fasturtec/Elitek) is a new generation of recombinant urate oxidase administred therapeutically by intravenous infusion for the prevention or treatment of hyperuricemia during chemotherapy. To ensure a long storage period, a freeze-dried formulation was developed to guarantee the molecular integrity and enzyme activity. Screening of potential excipients was the first stage of the preformulation study. The selection was based on stability results (rasburicase solution with excipient) obtained with the isoelectric focusing profiles and residual enzyme activity. The different excipients were classified as stabilising, neutral or destabilising. A stability study was then carried out on different freeze-dried formulations containing the usual bulking agents for freeze-drying, excipients with a high glass transition temperature or competitive enzyme inhibitors having a stabilising effect. A mannitol/alanine mixture in phosphate buffer was selected from these preliminary results. Finally, the optimal content of mannitol and alanine in the freeze-dried powder was determined by an experimental design study. The water content and the appearance of the "cake", the osmolality, pH, clarity, and enzyme activity of the reconstituted solution were assessed. The formula with a mannitol/alanine ratio of 0.7 was found to be the best composition. Differential scanning calorimetry and ThermoStimulated Current technique experiments were carried out to study the amorphous phase. A glass transition temperature of about 45-500 degrees C was found. Glassy state is known to preserve stability, which was verified by the real stability data. X-ray diffraction studies have shown that alanine is in a crystallised state and that mannitol remains amorphous. Crystallised excipients participate in forming the structure of the powder and therefore help to prevent any collapse. Amorphous mannitol creates a surrounding medium favourable to the stability of the protein.

Evaluation of the reproductive and developmental toxicity of the D-003, a mixture of long-chain fatty acids, in rats and rabbits.

D-003 is a mixture of long-chain fatty acids isolated and purified from sugar cane wax with cholesterol-lowering properties. D-003 given orally (500 and 1000 mg/kg/day) to female rats for 15 days prior to mating, through mating and gestation to day 21 of lactation and male rats for 4 weeks prior and during mating did not induce toxic effects on reproduction. There were no significant reductions in the number of animals that conceived, in the numbers of pups born to those that did conceive, in the numbers of pups that survived until weaning, and in their body weights at weaning. Drug-treated and control groups' offspring were comparable in growth, physical and behavioral development, spontaneous activity and reproductive performance. Pregnant New Zealand rabbits were given D-003 as oral doses of 500 and 1000 mg/kg/day on days 6 through 18 of gestation without any evidence of embryotoxicity or teratogenicity. The no-observed-effect dose in these two experimental studies was 1000 mg/kg/day. After assessment of the potential of high doses of D-003 to act on developing embryo and reproduction process, no evidence supports the conclusion that D-003 is a reproductive and developmental toxicant/teratogen.

Occupational injuries identified by an emergency department based injury surveillance system in Nicaragua.

OBJECTIVES: To identify and describe the work related injuries in both the formal and informal work sectors captured in an emergency department based injury surveillance system in Managua, Nicaragua. SETTING: Urban emergency department in Managua, Nicaragua serving 200-300 patients per day. METHODS: Secondary analysis from the surveillance system data. All cases indicating an injury while working and seen for treatment at the emergency department between 1 August 2001 and 31 July 2002 were included. There was no exclusion based on place of occurrence (home, work, school), age, or gender. RESULTS: There were 3801 work related injuries identified which accounted for 18.6% of the total 20 425 injures captured by the surveillance system. Twenty seven work related fatalities were recorded, compared with the 1998 International Labor Organization statistic of 25 occupational fatalities for all of Nicaragua. Injuries occurring outside of a formal work location accounted for more than 60% of the work related injuries. Almost half of these occurred at home, while 19% occurred on the street. The leading mechanisms for work related injuries were falls (30%), blunt objects (28%), and stabs/cuts (23%). Falls were by far the most severe mechanism in the study, causing 37% of the work related deaths and more than half of the fractures. CONCLUSIONS: Occupational injuries are grossly underreported in Nicaragua. This study demonstrated that an emergency department can be a data source for work related injuries in developing countries because it captures both the formal and informal workforce injuries. Fall prevention initiatives could significantly reduce the magnitude and severity of occupational injuries in Managua, Nicaragua.

[Repercussion of age on management of neoplastic patients in an Internal Medicine Service]. / Relación de la edad con el manejo de los pacientes diagnosticados de neoplasia en un Servicio de Medicina Interna.

AIM: To determine whether age is a factor affecting the management of patients diagnosed with neoplastic disease in an internal medicine service. PATIENTS AND METHODS: Prospective study of 388 patients diagnosed with cancer in the internal medicine service of a large public health teaching hospital. We evaluated clinical characteristics, diagnostic procedures, types and stage of neoplasm, referral after hospital discharge and treatment. A comparative study based on age was performed between patients 65 years older and patients under this age. RESULTS: The 388 cancer patients accounted for 12% of hospital admissions in our service. Among the total, 62% were > or = 65 years old. Constitutional syndrome, the most frequently associated symptom and the main reason for the consultation, was more common in the > or = 65-year-old group. Lung cancer was predominant in men and hematologic neoplasms in women. Patients > or = 65 were referred more frequently to internal medicine physicians, general practitioners and home palliative assistance services (p < 0.05) and they received only palliative treatment in a greater percentage of cases (50% vs. 37%, p = 0.001). CONCLUSIONS: The incidence of neoplasms in our service was high (12%), with a considerable percentage of patients in advanced phases of the disease (83%). Age was not related to diagnostic methods nor was it determinant in the staging, but it did have repercussions on treatment; patients > or = 65 received palliative treatment alone more often than younger patients.

[Hypernephroma associated motor neuron disease. Presentation of a case]. / Enfermedad de la motoneurona asociada a hipernefroma. Presentación de un caso.

INTRODUCTION: Paraneoplastic motor neuron disease are rare among patients with renal cell carcinoma. OBJECTIVE: Present the clinical and electrophysiological evolution of a patient with a motor neuron disease and hypernephrome. CASE REPORT: A 60 years old woman, affected only by high level pressure since 10 years ago. She noticed sudden palsy of the left leg and 10 months later an abdominal ultrasound showed a renal cell carcinoma, discovered without other symptoms than neurologic. After radical nephrectnomy, the patient was treated with recombinant interferon alpha 2b. The neurologic damage advanced and she has a flaccid weakness and muscle atrophy in the legs and brisk reflexes, also in wasted limbs. There is Babinski, fasciculations, light flaccid dysarthria and laryngospasm. Peripheral nerve conduction studies are within normal limits. The electromyogram show positive sharp waves in both legs and left hand. Recruitment patterns are decreased and there are fasciculations in the tongue, upper and lower limbs. The magnetic resonance of the brain and spinal cord is normal. There are not evidence of metastasis. The question of whether or not this is a paraneoplastic form of motor neuron disease remain unclear. CONCLUSION: This case suggest the need to consider a renal cell carcinoma in the course of a motor neuron disease.

[Bronchiolitis obliterans organizing pneumonia associated with Legionella pneumophila]. / Bronquiolitis obliterante con neumonía organizativa asociada a Legionella pneumophila.

Bronchitis obliterans organizing pneumonia (BOOP) is an unusual pulmonary condition. The clinical features and the radiologic findings are useful for the diagnosis of BOOP. However it is necessary to confirm its presence by an open or transbronchial pulmonary biopsy specimen. BOOP is usually idiopathic, although it may also occur in association with connective tissue disease, some haematologic disorders and in response to viral infections. The association of Legionella pneumophila infection with BOOP is very rare.

Pleural-fluid myeloperoxidase in complicated and noncomplicated parapneumonic pleural effusions.

The diagnostic accuracy of myeloperoxidase (MPO) in pleural fluid, for differentiating between complicated and noncomplicated parapneumonic pleural effusions (PPE) evaluated prospectively. Seventy patients aged >18 yrs with PPE (36 complicated and 34 noncomplicated) were studied after admission to a tertiary referral teaching hospital. MPO concentration was measured in plasma and pleural fluid using a double-antibody competitive radioimmunoassay. The concentrations of MPO in complicated and noncomplicated PPE were compared using a Mann-Whitney U-test and multiple logistic regression models were used to predict the odds that an effusion was complicated. MPO pleural-fluid concentrations were significantly higher in complicated than in noncomplicated PPE. After excluding purulent effusions, pleural-fluid MPO was the marker that best differentiated between the two types of PPE: the area under the receiver operating characteristic curve was 0.912, the sensitivity was 87.5% and the specificity was 85.1% at a cut-point limit of 3.000 microg x L(-1). The authors concluded that the concentration of pleural-fluid myeloperoxidase helps to differentiate between nonpurulent complicated and noncomplicated parapneumonic pleural effusions.

Structural versatility of oxalamide-based compounds: a computational study on the isomerization of the oxalamide group and the structural preferences of the polyoxalamides.

The conformational properties of the oxalamide group and crystal structure of several polyoxalamides have been investigated by computational methods. First, a detailed quantum mechanical study of the conformational preferences of N,N'-dimethyloxalamide is reported. Results, which were obtained at the MP2/6-31G(d) level, provide not only the minimum energy conformations but also a description of the energetics and structural changes associated to the isomerization process of the oxalamide group. These quantum mechanical results together with those obtained from additional calculations have been used to develop a set of force-field parameters for the oxalamide group. Molecular mechanics calculations have been performed to test the parameters and to provide new information in terms of energy contributions about the isomerization of the oxalamide group. On the other hand, the new set of parameters has been used to investigate the structural preferences of polyoxalamides (-[NH-CO-CO-NH-(CH(2))(n)]-) by PCSP calculations. Results indicated that polyoxalamides with an even number of methylene groups adopt a structure with one hydrogen bonding direction, whereas polymers with an odd number of methylene groups prefer a structure with two hydrogen bonding directions. The latter crystal structure is completely different from that observed in conventional polyamides and has been investigated in detail through Monte Carlo simulations.

Poly(gamma-glutamic acid) in aqueous solution: molecular dynamics simulations of 10- and 20-residue chains at different temperatures.

A series of molecular dynamics simulations in aqueous solution have been carried out in order to investigate the effects of the length of the peptide chain and the temperature on the helical conformation of un-ionized poly(gamma-D-glutamic acid). The results reveal that the helix is not stable for a small number of residues independent of the temperature. On the other hand, the temperature induces a conformational transition from the helical state to the random coil. Analysis of the energy of the whole system indicates that the helix is more stable than the random coil state by about 5 kcal/mol, even although the solvation potential energy is lower in the latter than in the former.

Pleural fluid myeloperoxidase as a marker of infectious pleural effusions.

Background: The aim of this study was to establish the diagnostic accuracy of neutrophil markers (elastase, lysozyme, myeloperoxidase) found in pleural fluid in differentiating between infectious and non-infectious pleural effusions (PE). Methods: We studied 184 patients over 18 years of age with PE, classified as either infectious (34 complicated parapneumonic, 32 non-complicated parapneumonic, 45 tuberculous) or non-infectious (31 neoplasms and 42 undiagnosed exudates). Polymorphonuclear elastase (PMN-E) was determined using an immunoactivation method and lysozyme using a turbidimetric method. Myeloperoxidase (MPO) was measured by double antibody competitive radioimmunoassay. Receiver operating characteristic (ROC) curves were used to evaluate diagnostic accuracy. Results: Pleural fluid MPO was the biochemical marker that best differentiated between infectious and non-infectious PE. The ROC area under the curve (AUC) for myeloperoxidase was 0.86. MPO values over 550 &mgr;g/l diagnosed infectious PE with a specificity of 90.4% and a sensitivity of 77.4%. After excluding purulent parapneumonic PE, the sensitivity of a pleural MPO value >/=550 &mgr;g/l was 72.6%. Conclusions: Pleural fluid MPO was the marker that best differentiated between infectious and non-infectious PE.

[Evaluation of motor and sensory neuroconduction of the median nerve in patients with carpal tunnel syndrome treated with non-coherent light emitted by gallium arsenic diodes]. / Evaluación de la neuroconducción motora y sensitiva del nervio mediano en pacientes portadores de síndrome del túnel del carpo tratados con luz no coherente emitida por diodos de arseniuro de galio.

INTRODUCTION: The treatment selection in the carpal tunnel syndrome according to the damage of the median nerve is important and all of these have adverse effects. A good alternative without undesired reactions is irradiation of the carpal tunnel with not coherent light between 920 and 940 nm emitted by gallium arsenide diodes, resembling the physic and therapeutic laser effects. PATIENTS AND METHODS: Twenty-six female patients with idiopathic middle carpal tunnel syndrome were irradiated 15 minutes daily during three weeks. The median nerve motor and sensitive neuroconduction was studied before and immediately after the treatment. RESULTS: The abnormal neuroconduction variables (latency, amplitude and velocity conduction) did not modify when treatment concluded, in spite of all the patients reported disappearance of pain and numbness in damaged hands. CONCLUSIONS: Not coherent light does not change the fibers functional state explored by conventional neuroconductions techniques. It remains to know if this light produces fine fibers improvement.