[Translated article] Mpox - Formerly Monkey Pox - in Dermatology: A Review of Epidemiologic Features, Clinical Presentation, Diagnosis, and Treatment

Mpox is an emerging zoonotic disease that has spread rapidly around the world. It has been declared a public health emergency of international concern by the World Health Organization. This review is an update for dermatologists on the epidemiology, clinical presentation, diagnosis, and treatment of Mpox. The primary mode of transmission in the current outbreak is close physical contact during sexual activity. Although most of the initial cases were reported in men who have sex with men, anyone who has close contact with an infected person or contaminated fomites is at risk. Classic prodromal features of Mpox include subclinical manifestations and a mild rash. Complications are common but rarely require hospitalization. Polymerase chain reaction analysis of mucocutaneous lesions is the test of choice for a definitive diagnosis. In the absence of specific treatments, management focuses on symptomatic relief.

Mpox - Formerly Monkey Pox - in Dermatology: A Review of Epidemiologic Features, Clinical Presentation, Diagnosis, and Treatment

Mpox is an emerging zoonotic disease that has spread rapidly around the world. It has been declared a public health emergency of international concern by the World Health Organization. This review is an update for dermatologists on the epidemiology, clinical presentation, diagnosis, and treatment of Mpox. The primary mode of transmission in the current outbreak is close physical contact during sexual activity. Although most of the initial cases were reported in men who have sex with men, anyone who has close contact with an infected person or contaminated fomites is at risk. Classic prodromal features of Mpox include subclinical manifestations and a mild rash. Complications are common but rarely require hospitalization. Polymerase chain reaction analysis of mucocutaneous lesions is the test of choice for a definitive diagnosis. In the absence of specific treatments, management focuses on symptomatic relief.

Effect of decreasing dietary crude protein in fattening calves on the emission of ammonia and greenhouse gases from manure stored under aerobic and anaerobic conditions

Dietary strategies can potentially help to reduce nitrogen (N) emissions and decrease the environmental impact of beef production. This study aimed to evaluate the effects of dietary crude protein (CP) concentration on animal performance, N excretion, and manure N volatilisation of finishing Holstein animals. In a first study, 105 Holstein bulls (BW 344 ± 2.6 kg; age 252 ± 0.9 days) were allocated to eight pens to evaluate the effect of two treatments (medium (M) and low (L), which contained CP 14.5% and 12% on a DM basis, respectively) on performance, and results confirmed that dietary CP decrease did not impair animal growth. In a second study, N excretion study, 24 Holstein heifers (BW 310 ± 5.3 kg; age 251 ± 1.4 days) were distributed randomly depending on the initial BW to three treatments (high (H), M, and L, which contained CP 17%, 14.5% and 12% on a DM basis, respectively). Based on N excretion, urinary N excretion was greater (P < 0.001) in H than in M and L diets, but no differences in faecal N excretion were observed among treatments. A third study with in vitro assays under aerobic and anaerobic conditions was designed to analyse gaseous emissions (volatilisation of N and carbon, C) during the storage stage of manure. Manure, faecal and urine samples, mixed at a ratio of 1:1 (wet weight), were collected during the N excretion study (manure-H, manure-M, manure-L). Under aerobic conditions, manure-M and manure-L showed a delay of 4-5 days in manure ammonia emission compared with manure-H (P < 0.01). Total N content was lower (P < 0.01) in manure-L compared with manure-M and manure-H, but N volatilisation (percentage relative to initial N) in manure-L and manure-M was greater (P < 0.01) than in manure-H. In contrast, the anaerobic N volatilisation was 20 times greater in manure-M and 10 times greater in manure-H compared with manure-L. Under aerobic and anaerobic conditions, the emission of C, as C-CO₂ and C-CH₄, was greater in manure-L than in manure-H and manure-M. Therefore, the decrease of dietary CP concentration from 17% to 14.5% and 12% is an efficient strategy to reduce urinary N excretion by 40%, without impairing performance, and also to reduce manure N losses through ammonia volatilisation under anaerobic conditions. However, a dietary CP content of 14.5% resulted in less environmental impact than a CP content of 12.8% when also considering manure emissions under aerobic or anaerobic conditions.

Effects of dietary almond- and olive oil-based docosahexaenoic acid- and vitamin E-enriched beverage supplementation on athletic performance and oxidative stress markers

Functional beverages based on almonds and olive oil and enriched with α-tocopherol and docosahexaenoic acid (DHA) could be useful in modulating oxidative stress and enhancing physical performance in sportsmen. The aim of this work was to evaluate the effects of supplementation with functional beverages on physical performance, plasma and erythrocyte fatty acids' and polyphenol handling, oxidative and nitrative damage, and antioxidant and mitochondrial gene expression in young and senior athletes. Athletes performed maximal exercise tests before and after one month of dietary supplementation and blood samples were taken immediately before and one hour after each test. The beverages did not alter performance parameters during maximal exercise. Supplementation increased polyunsaturated and reduced saturated plasma fatty acids while increasing the DHA erythrocyte content; it maintained basal plasma and blood polyphenol levels, but increased the blood cell polyphenol concentration in senior athletes. Supplementation protects against oxidative damage although it enhances nitrative damage in young athletes. The beverages enhance the gene expression of antioxidant enzymes in peripheral blood mononuclear cells after exercise in young athletes.

Use of nebulized antimicrobials for the treatment of respiratory infections in invasively mechanically ventilated adults: a position paper from the European Society of Clinical Microbiology and Infectious Diseases

With an established role in cystic fibrosis and bronchiectasis, nebulized antibiotics are increasingly being used to treat respiratory infections in critically ill invasively mechanically ventilated adult patients. Although there is limited evidence describing their efficacy and safety, in an era when there is a need for new strategies to enhance antibiotic effectiveness because of a shortage of new agents and increases in antibiotic resistance, the potential of nebulization of antibiotics to optimize therapy is considered of high interest, particularly in patients infected with multidrug-resistant pathogens. This Position Paper of the European Society of Clinical Microbiology and Infectious Diseases provides recommendations based on the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology regarding the use of nebulized antibiotics in invasively mechanically ventilated adults, based on a systematic review and meta-analysis of the existing literature (last search July 2016). Overall, the panel recommends avoiding the use of nebulized antibiotics in clinical practice, due to a weak level of evidence of their efficacy and the high potential for underestimated risks of adverse events (particularly, respiratory complications). Higher-quality evidence is urgently needed to inform clinical practice. Priorities of future research are detailed in the second part of the Position Paper as guidance for researchers in this field. In particular, the panel identified an urgent need for randomized clinical trials of nebulized antibiotic therapy as part of a substitution approach to treatment of pneumonia due to multidrug-resistant pathogens.

Key considerations on nebulization of antimicrobial agents to mechanically ventilated patients

Nebulized antibiotics have an established role in patients with cystic fibrosis or bronchiectasis. Their potential benefit to treat respiratory infections in mechanically ventilated patients is receiving increasing interest. In this consensus statement of the European Society of Clinical Microbiology and Infectious Diseases, the body of evidence of the therapeutic utility of aerosolized antibiotics in mechanically ventilated patients was reviewed and resulted in the following recommendations: Vibrating-mesh nebulizers should be preferred to jet or ultrasonic nebulizers. To decrease turbulence and limit circuit and tracheobronchial deposition, we recommend: (a) the use of specifically designed respiratory circuits avoiding sharp angles and characterized by smooth inner surfaces, (b) the use of specific ventilator settings during nebulization including use of a volume controlled mode using constant inspiratory flow, tidal volume 8 mL/kg, respiratory frequency 12 to 15 bpm, inspiratory:expiratory ratio 50%, inspiratory pause 20% and positive end-expiratory pressure 5 to 10 cm H₂O and (c) the administration of a short-acting sedative agent if coordination between the patient and the ventilator is not obtained, to avoid patient's flow triggering and episodes of peak decelerating inspiratory flow. A filter should be inserted on the expiratory limb to protect the ventilator flow device and changed between each nebulization to avoid expiratory flow obstruction. A heat and moisture exchanger and/or conventional heated humidifier should be stopped during the nebulization period to avoid a massive loss of aerosolized particles through trapping and condensation. If these technical requirements are not followed, there is a high risk of treatment failure and adverse events in mechanically ventilated patients receiving nebulized antibiotics for pneumonia.

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine: Brussels, Belgium. 15-18 March 2016

[This corrects the article DOI: 10.1186/s13054-016-1208-6.].

Primary Graft Dysfunction and Mortality Following Lung Transplantation: A Role for Proadrenomedullin Plasma Levels

Primary graft dysfunction (PGD) after lung transplantation (LT) is a heterogeneous syndrome that comprises clinical presentations with diverse grades of severity. Proadrenomedullin (proADM) levels may be associated with PGD and may enhance its relationship with outcomes. We prospectively included 100 LT recipients. Plasma levels of proADM were measured at 24, 48 and 72 h after admission to the intensive care unit (ICU). We assessed their relationship with PGD grade and ICU mortality. Fifty patients (50%) presented grade 3 PGD at ICU admission. Twenty-two patients (22%) developed grade 3 PGD at 72 h, the only grade associated with higher mortality (odds ratio 6.84, 95% confidence interval [CI] 1.47-38.44). ProADM levels measured at 24 h (3.25 vs. 1.61 nmol/L; p = 0.016) and 72 h (2.17 vs. 1.35 nmol/L; p = 0.011) were higher in these patients than the rest of the population. When we added the individual predictive utility of grade 3 PGD at 72 h for ICU mortality (area under the curve [AUC] 0.72, 95% CI 0.53-0.90) to that of ProADM at 72 h, the predictive value of the model improved (AUC 0.81, 95% CI 0.65-0.97). Higher levels of proADM measured following LT are associated with grade 3 PGD at 72 h. ProADM enhances the association of this entity with mortality.

Global survey on nebulization of antimicrobial agents in mechanically ventilated patients: a call for international guidelines

Nebulized antimicrobial agents are increasingly administered for treatment of respiratory infections in mechanically ventilated (MV) patients. A structured online questionnaire assessing the indications, dosages and recent patterns of use for nebulized antimicrobial agents in MV patients was developed. The questionnaire was distributed worldwide and completed by 192 intensive care units. The most common indications for using nebulized antimicrobial agent were ventilator-associated tracheobronchitis (VAT; 58/87), ventilator-associated pneumonia (VAP; 56/87) and management of multidrug-resistant, Gram-negative (67/87) bacilli in the respiratory tract. The most common prescribed nebulized agents were colistin methanesulfonate and sulfate (36/87, 41.3% and 24/87, 27.5%), tobramycin (32/87, 36.7%) and amikacin (23/87, 26.4%). Colistin methanesulfonate, amikacin and tobramycin daily doses for VAP were significantly higher than for VAT (p < 0.05). Combination of parenteral and nebulized antibiotics occurred in 50 (86%) of 58 prescriptions for VAP and 36 (64.2%) of 56 of prescriptions for VAT. The use of nebulized antimicrobial agents in MV patients is common. There is marked heterogeneity in clinical practice, with significantly different in use between patients with VAP and VAT. Randomized controlled clinical trials and international guidance on indications, dosing and antibiotic combinations to improve clinical outcomes are urgently required.

Early postoperative management of lung transplantation

Lung transplantation is a widely accepted therapeutic option for patients with end-stage lung disease. However, despite the significant medical progress achieved since the first human lung transplant was performed in 1963, perioperative and long-term patient outcomes are still jeopardised by a variety of complications. Infection and rejection are among the most feared complications in the early post-transplantation period because they are difficult to treat and can have a long-lasting impact on the quality of life and overall life expectancy. Multidisciplinary management of lung transplant recipients focusing on the prevention or early detection of complications, particularly during the early postoperative phase, may improve the short and long-term outcomes of those patients benefiting from this life-saving intervention. However, in the absence of internationally recognised guidelines, the optimal strategies for managing lung transplant recipients remain unclear. This article presents a practical approach to the management of the early post-transplantation period aiming at standardising clinical care and improving patient outcome.

The sounds of cardiac arrest: innovating to obtain an accurate record during in-hospital cardiac arrest

BACKGROUND

To obtain an accurate audit during in-hospital cardiac arrest, following recommendations of the Utstein style and measuring time intervals between the different interventions, is difficult.

OBJECTIVE

To assess whether the use of an audio recording system during in-hospital cardiac arrest resuscitation allows the register of more items during cardiopulmonary resuscitation.

MATERIAL AND METHODS

Prospective observational study between January 2008 and December 2009. The population that were included, were hospitalized patients and non-hospitalized patients assisted by a cardiac arrest team, except for critical areas. An audio recording system with a timer was turned on when cardiac arrest team was alerted. Recordings were reviewed to fill in the items recommended by the Utstein style. Time intervals were calculated. Mean number of completed items per patient were compared between recorded and non-recorded cardiac arrest.

RESULTS

119 CA team alerts took place. 64 (53.7%) cases were real CA and 37 (57.8%) of them were properly recorded. A mean number of items per patient in recorded cardiac arrest cases were 18.18 (±3.2) vs. 15.96 (±4.1) in non-recorded cardiac arrest cases (p<0.05). In the recorded cases, mean times were: alert - arrival: 1.23 (±0.95)min; arrival - cardiopulmonary resuscitation initiation: 0.63 (±0.38)min; arrival - first defibrillation: 2.06 (±1.33)min; arrival - intubation: 8.42 (±4.64)min; arrival - first adrenaline: 3.30 (±1.98)min.

CONCLUSIONS

The audio recording system permits the register of a larger number of items per patient during in-hospital cardiac arrest and allows measurement of time intervals between the different interventions during cardiopulmonary resuscitation.

Modeling the spontaneous Ca2+ oscillations in astrocytes: Inconsistencies and usefulness

Spontaneous calcium (Ca2+) oscillations (SCOs) in astrocytes might be a crucial signaling for the multipurpose role of this type of cell in several brain functions. To interpret experimental data of astrocytic SCOs, which has been largely observed in the last decade, several groups have attempted to accommodate biophysical models that were developed in the past for Ca2+ signaling in other cell types. In most of the cases, only predictive strategies were used to estimate specific parameters of these modified models from actual experiments. In this study, we discuss the most remarkable models used to describe Ca2+ signaling in astrocytes. At the same time, we aim to revise the particulars of applying these models to interpret epifluorescent time series obtained from large regions of interest. Specially, we developed a detailed model for global Ca2+ signaling in the somata of astrocytes. In order to estimate some of the parameters in our model, we propose a deductive reasoning strategy, i.e., a statistical inference method that results from combining a filtering technique and a maximum likelihood principle. By means of computer simulations, we evaluate the accuracy of this estimation's strategy. Finally, we use the new model, in combination with a recent experimental findings by our group, to estimate the degree of cluster coupling inside the soma during the genesis of global Ca2+ events.

Multidisciplinary approach and multimodal therapy in resected pancreatic cancer. Observational study

OBJECTIVE

Analysis and evaluation of a multidisciplinary approach, postoperative results and survival of a group of patients with resected pancreatic cancer after a multimodal therapy.

DESIGN

DESCRIPTIVE, prospective and observational study.

PATIENTS

Between January 2004 and December 2004, 124 patients with pancreatic cancer were evaluated. In 30 patients pancreatic resection was performed, and they are the object of this study. Results of preoperative evaluation, postoperative morbidity and mortality, and long term survival were studied.

RESULTS

Diagnostic evaluation was completed in ambulatory basis in 20% of the patients. In 63% of cases, admission was done in the same day of surgery. In 3 patients (9%), tumor resection was not achieved, therefore, concordance between radiological and surgical resectability rate was 91%. Resectability rate was 24.1%. Surgical Mortality was 3.3%, with a global morbidity rate of 56.6%. Survival at one, two, three and, four years was 76.2%, 56.3%, 43%, y 27.3% respectively.

CONCLUSIONS

Technological development and coordination of efforts in multidisciplinary teams offer an accurate evaluation of tumor involvement, and may reduce the number of laparotomies without tumor resection. The application of a systematic and generalized multimodal treatment in pancreatic cancer is progressively showing a tendency of progressive increase in resectability and survival rates in pancreatic cancer.

[Electrical impedance tomography in acute lung injury]

Electrical impedance tomography has been described as a new method of monitoring critically ill patients on mechanical ventilation. It has recently gained special interest because of its applicability for monitoring ventilation and pulmonary perfusion. Its bedside and continuous implementation, and the fact that it is a non-ionizing and non-invasive technique, makes it an extremely attractive measurement tool. Likewise, given its ability to assess the regional characteristics of lung structure, it could be considered an ideal monitoring tool in the heterogeneous lung with acute lung injury. This review explains the physical concept of bioimpedance and its clinical application, and summarizes the scientific evidence published to date with regard to the implementation of electrical impedance tomography as a method for monitoring ventilation and perfusion, mainly in the patient with acute lung injury, and other possible applications of the technique in the critically ill patient. The review also summarizes the limitations of the technique and its potential areas of future development.

Neoadjuvant continuous infusion of weekly 5-fluorouracil and escalating doses of oxaliplatin plus concurrent radiation in locally advanced oesophageal squamous cell carcinoma: results of a phase I/II trial

Oxaliplatin and 5-fluorouracil have a significant activity in locally advanced oesophageal squamous cell cancer (OSCC). However, their optimal dosage and efficacy when combined with concurrent radiotherapy as neoadjuvant treatment are unknown. This non-randomised, phase I/II study aimed to define the maximum tolerated dose (MTD) and assessed the histopathological tumour response rate to neoadjuvant oxaliplatin in weekly escalating doses (40, 45, 50 mg m⁻²) and continuous infusional 5-fluorouracil (CI-5FU; 225 mg m⁻²) plus concurrent radiotherapy. Patients had resectable OSCC. Resection was scheduled for 4–6 weeks after chemoradiotherapy. During phase I (dose escalation; n=19), weekly oxaliplatin 45 mg m⁻² plus CI-5FU 225 mg m⁻² was established as the MTD and was the recommended dosage for phase II. Oesophageal mucositis was the dose-limiting toxicity at higher doses. During phase II, histopathological responses (<10% residual tumour cells within the specimen) were observed in 10 of 16 patients (63%; 95% confidence interval: 39–82%). Overall, 16 of the 25 patients (64%) who underwent resection had a histopathological response; tumour-free resection (R0) was achieved in 80%. Neoadjuvant weekly oxaliplatin 45 mg m⁻² plus CI-5FU 225 mg m⁻² with concurrent radiotherapy provides promising histological response rates and R0 resection rates in locally advanced OSCC.

Human herpes virus 8 (HHV8): Detection in peripheral blood mononuclear cells (PBMC) from Venezuelan patients with human immunodeficienccy virus-1 (HIV-1) infection with/without Kaposi‘s sarcoma (KS)

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Background: The nucleic acid of HHV8 is present in the PBMCs of between 50% and 90% of KS patients,7% and 10% of HIV-1 infected patients without KS.We studied the prevalence of HHV8 in PBMCs from venezuelan patients with HIV-1 infection with/without KS. Methods: Seventy-six patients with HIV-1 infection without KS and 15 patients with KS associated with HIV-1 infection were included. Socioepidemiologic characteristics of HIV-1 infected patients were as follows: mean age (36 years, range 19–69 years); 79% of patients were male, 93% were heterosexuals, 9% were treated with antiherpetic drugs and 74% were on HAART; mean T-CD4 count was 362 cel/mm3. Socioepidemiologic characteristics of patients with KS associated with HIV-1 infection were as follows: mean age 39 years (range, 20- 69 years); 93% of patients were male, 87% were homosexuals, 93% belonged to a ‘high risk group‘, 7% were treated with antiherpetic drug and 80% were on HAART; mean T-CD4 count was 86 cel/mm3. PBMCs were isolated on a Fycoll Hypaque gradient and then stored at -70°C until processed. DNA was extracted from the samples by a standard phenol/chloroform extraction procedure.All DNA samples were confirmed to be amplifiable by PCR primers specific for a conserved region of the human beta-globin gen. Positive (DNA from KS biopsy) and negative controls were included. DNA was PCR amplified using the KS1 and KS2 primers specific for the HHV8 ORF 26. PCR reactions were considered positive only if the PCR products hybridized in the expected 233 bp region. Results: None of HIV-1 infected patients showed the presence of HHV8 in the PBMCs, and after a follow-up of two years, none has developed KS. HHV8 was detected in the PBMCs from 20 % of patients with KS. All patients belonged to a ‘high risk group‘, were male and homosexuals. None received blood transfusion. Conclusions: These preliminary data suggest that the prevalence of HHV8 in PBMCs from venezuelan HIV-1 infected patients with/without KS is probably low in comparison with patiens from USA and Europe.

No significant financial relationships to disclose.

Polyinosinic acid induces TNF and NO production as well as NF-kappaB and AP-1 transcriptional activation in the monocytemacrophage cell line RAW 264.7

OBJECTIVE

This study evaluates the poly inosinic acid (poly I)-induced activation in the murine monocytemacrophage cell line RAW 264.7, which led to an inflammatory phenotype.

MATERIAL

RAW 264.7, and WEHI 164 cell lines were used.

RESULTS

The activation process is characterized by the acquisition of a mature macrophage morphology and the production of inflammatory mediators tumor necrosis factor (TNF) and nitric oxide (NO). The activation by poly I has distinctive features. Thus, poly I induced an increase in nuclear factor kappaB (NF-kappaB) transcriptional activity due to a long-term degradation of inhibitory NF-kappaB (IkappaB) beta while lipopolysaccharide (LPS) induced the degradation of both IkappaBalpha and IkappaBbeta. Poly I also induced an increase in activator protein 1 (AP-1) transcriptional activity, possibly due to the activation of the mitogen activated protein kinases (MAPKs) ERK, Jun N terminal kinase (JNK) and p38. Dextran sulphate (DS) efficiently inhibited the activation induced by poly I including the production of the inflammatory mediators. Dextran sulphate also inhibited AP-1 and NF-kappaB transcriptional activities in poly I-stimulated cells. RAW 264.7 cells express macrophage scavenger receptor 1 (Msr1) type I and Msr1 type II that are differently up-regulated upon treatment with poly I.

CONCLUSIONS

The results presented demonstrate that the well-known blocker of scavenger receptors poly I activates macrophages to produce TNF and NO, triggering specific signal transduction pathways.

Fusing EEG and fMRI based on a bottom-up model: inferring activation and effective connectivity in neural masses

The elucidation of the complex machinery used by the human brain to segregate and integrate information while performing high cognitive functions is a subject of imminent future consequences. The most significant contributions to date in this field, known as cognitive neuroscience, have been achieved by using innovative neuroimaging techniques, such as electroencephalogram (EEG) and functional magnetic resonance imaging (fMRI), which measure variations in both the time and the space of some interpretable physical magnitudes. Extraordinary maps of cerebral activation involving function-restricted brain areas, as well as graphs of the functional connectivity between them, have been obtained from EEG and fMRI data by solving some spatio-temporal inverse problems, which constitutes a top-down approach. However, in many cases, a natural bridge between these maps/graphs and the causal physiological processes is lacking, leading to some misunderstandings in their interpretation. Recent advances in the comprehension of the underlying physiological mechanisms associated with different cerebral scales have provided researchers with an excellent scenario to develop sophisticated biophysical models that permit an integration of these neuroimage modalities, which must share a common aetiology. This paper proposes a bottom-up approach, involving physiological parameters in a specific mesoscopic dynamic equations system. Further observation equations encapsulating the relationship between the mesostates and the EEG/fMRI data are obtained on the basis of the physical foundations of these techniques. A methodology for the estimation of parameters from fused EEG/fMRI data is also presented. In this context, the concepts of activation and effective connectivity are carefully revised. This new approach permits us to examine and discuss some future prospects for the integration of multimodal neuroimages.

fMRI activation maps based on the NN-ARx model

The most significant progresses in the understanding of human brain functions have been possible due to the use of functional magnetic resonance imaging (fMRI), which when used in combination with other standard neuroimaging techniques (i.e., EEG) provides researchers with a potential tool to elucidate many biophysical principles, established previously by animal comparative studies. However, to date, most of the methods proposed in the literature seeking fMRI signs have been limited to the use of a top-down data analysis approach, thus ignoring a pool of physiological facts. In spite of the important contributions achieved by applying these methods to actual data, there is a disproportionate gap between theoretical models and data-analysis strategies while trying to focus on several new prospects, like for example fMRI/EEG data fusion, causality/connectivity patterns, and nonlinear BOLD signal dynamics. In this paper, we propose a new approach which will allow many of the abovementioned hot topics to be addressed in the near future with an underlying interpretability based on bottom-up modeling. In particular, the theta-MAP presented in the paper to test brain activation corresponds very well with the standardized t test of the SPM99 toolbox. Additionally, a new Impulse Response Function (IRF) has been formulated, directly related to the well-established concept of the hemodynamics response function (HRF). The model uses not only the information contained in the signal but also that in the structure of the background noise to simultaneously estimate the IRF and the autocorrelation function (ACF) by using an autoregressive (AR) model with a filtered Poisson process driving the dynamics. The short-range contributions of voxels within the near-neighborhood are also included, and the potential drift was characterized by a polynomial series. Since our model originated from an immediate extension of the hemodynamics approach [Friston, K.J., Mechelli, A., Turner, R., Price C.J. (2000a). Nonlinear responses in fMRI: the balloon model, volterra kernels, and other hemodynamics. NeuroImage 12, 466-477.], a natural interpretability of the results is feasible.

[Lactose malabsorption in ulcerative colitis. A case-control study]

BACKGROUND

The role of lactose malabsorption in ulcerative colitis is controversial. The aim of this study was to compare the prevalence of lactose malabsorption in a group of ulcerative colitis patients and a control group and to modify lactose consumption in view of the results.

METHODS

Lactose malabsorption was studied using the hydrogen breath test in 52 patients with ulcerative colitis and 34 controls after ingestion of 25 g of lactose. A questionnaire on ingestion of milk products was also administered.

RESULTS

Of the 52 patients with ulcerative colitis, 13 (25%) presented lactose malabsorption compared with 11 of the 34 (32%) controls (p = 0.45). Twenty-four patients (46%) had been advised to completely eliminate lactose from their diets. Twenty-seven of the 39 patients without malabsorption had reduced or eliminated lactose consumption after being diagnosed with ulcerative colitis.

CONCLUSIONS

No significant differences in the prevalence of lactose malabsorption was found between patients with ulcerative colitis and controls. We believe that systematic elimination of lactose from the diets of these patients is erroneous. In our environment, we recommend the hydrogen breath test only in patients with symptoms of lactose intolerance.

[Ulcerative colitis with segmental involvement]

INTRODUCTION

Ulcerative colitis is a chronic inflammatory disease affecting areas of the colon or the full length. From the endoscopic point of view, ulcerative colitis presents lesions that stretch continuously from the rectum to variable colon segments, a characteristic that is of great value when distinguishing it from Crohn's disease. Continuous involvement, without healthy patches, justifies ending endoscopic exploration once the distal end of the lesion has been reached.

OBJECTIVE

To retrospectively study the frequency of segmental lesions in the colonoscopies performed in patients with ulcerative colitis.

METHODS

Diagnosis of ulcerative colitis and proctitis was established by clinical, endoscopic, histologic, analytical, and radiological criteria. The indication and number of endoscopies was made on the basis of the clinical criteria of diagnosis, acute episodes, refractoriness or dysplasia screening. The extent of the examination also depended on clinical criteria: the severity of the episode, tolerance to colonoscopy or the degree of cleansing.

RESULTS

A total of 155 coloscopies were performed. In 113 colonoscopies (73%) the distal end of the lesion was reached and in 70 (45%) the cecum was reached. Of the 80 patients, 27 (33%) presented ulcerative proctitis at diagnosis. Nine of the 80 patients (11.3%) biopsies were performed in healthy colonic patches, which confirmed histological normality. Six of the 9 patients were receiving no treatment. In all patients except two, the cecum was reached in one or more of the colonoscopies. The distribution of the segmental lesions varied but these were mainly found in the periappendicular region and in the cecum in 6 of the 7 patients in whom the cecum was reached. Of the 80 patients, endoscopic evidence of rectal sparing was found in 5 (6.3%); of these, 4 were receiving systemic or topical treatment. Histological analysis confirmed the absence of inflammatory lesions in these patients. The only patient who was not receiving treatment presented microscopic lesions compatible with ulcerative colitis.

CONCLUSIONS

Endoscopic segmental lesions in ulcerative colitis were present in 11.3% of patients. Segmental lesions were most frequently found in the cecum and periappendicular region. Endoscopic and histologic evidence of rectal sparing may be the result of systemic or topical treatment.

Light and electron microscopic analysis of liver biopsy samples from rheumatoid arthritis patients receiving long-term methotrexate therapy

OBJECTIVE

We study liver damage in forty-two patients with rheumatoid arthritis (RA) using light (LM) and electron microscopy (EM) and assess histological changes after four years of treatment with methotrexate (MTX).

PATIENTS AND METHODS

liver biopsies (LB) were taken before and after four years of treatment. Patients received weekly doses of between 7.5-15 mg of MTX.

RESULTS

Fourteen per cent of the baseline LB presented mild perisinusoidal fibrosis (Roenigk IIIA) and the rest a lower Roenigk grade; EM identified an increase in collagen fibers in the Disse spaces in 50% of baseline LB. Neither microscopy technique revealed histological progression in any of the sequential LB. Variables that correlated with histological abnormalities were patient's age, length of evolution of the disease, alcohol consumption and biochemical data (gammaglutamate transferase and albumin); the cumulative dose of MTX was not correlated with worse histological findings. Correlation between the two microscopy techniques was good, though EM was more sensitive than LM for the detection of fibrosis.

CONCLUSIONS

RA patients present with liver damage before treatment with MTX. The alterations are mild. At low doses MTX treatment is safe. In addition to the recommendations of the American College of Rheumatology, other factors associated with liver impairment are patient's age and length of evolution of the RA.

[Endoscopic management of foreign bodies in the esophagus. Results of a retrospective series of 501 cases]

We present the results of a retrospective study of endoscopic management (with flexible endoscopy) in 501 patients admitted for suspected ingestion of a foreign body between 1977 and 1997. The mean age of the patients was 55.73 19.38. Foreign bodies were found in the esophagus in 322 patients (64.3%) and endoscopic removal was successful in 307 (95.35%). More experienced endoscopists, with more than 45 cases, had a higher success rate (98.1%) than did less experienced endoscopists (87.9%) (p < 0.01). The most frequent type of foreign body in our series was meat bolus (32.8%). Underlying disease was found in 38.9%, and peptic stenosis was the most frequent. The only severe complication found was esophageal perforation in one patient (0.3%). Emergency flexible endoscopy is the most effective method for managing patients admitted for suspected ingestion of a foreign body and for the removal of foreign bodies located in the esophagus.