Selective immediate responders to amoxicillin and clavulanic acid tolerate penicillin derivative administration after confirming the diagnosis.

BACKGROUND: An increasing number of patients show immediate selective hypersensitivity reactions to clavulanic acid (CLV) and amoxicillin (AX), probably due to their increased prescription. The maintenance of this response should be established. OBJECTIVE: To assess that the immediate hypersensitivity selective response to AX or to CLV is maintained after repeated administration of penicillin G (PG)/penicillin V (PV) and AX. METHODS: Patients with proven immediate hypersensitivity to AX (Group A) or CLV (Group B) were included. Diagnosis was performed using skin tests with major and minor determinants of PG (PPL/MDM), AX and CLV and by drug provocation test (DPT) if required. Selectivity was established by confirming tolerance to PG/PV (Group A) and to PG/PV and AX (Group B). The maintenance of the selective response was verified by repeating DPT, 15 days after the initial investigation, with the same procedure. RESULTS: Of 51 patients, 78% belonged to Group A and 22% to Group B. Most had anaphylaxis. In Group A, 72% were skin test positive; 28% required DPT. In Group B, 63% were skin test positive; 37% required DPT. Only two AX-selective cases developed positive responses after re-provocation with PG/PV. No cases selective for CLV developed a positive response to PG, PV or AX. DISCUSSION: The selective response to AX appears consistent, and a response to penicillin determinants only develops in a minority of cases. For the case of CLV, the selective response appears not to be modified by exposure to penicillin determinants, meaning that patients with CLV allergy can take penicillin derivatives safely.

Preliminary findings on the antimony levels of Quiroga river water in the vicinity of a long-abandoned stibnite mine.

A UV-Vis spectrophotometric method was developed as a preliminary approach to the determination of antimony in water samples from a river that flows very close to an abandoned mining site. The analyte is complexed with ammonium pyrrolidinedithiocarbamate and absorbance of the complex is measured at 291.06 nm. The standard additions method is mandatory in view of the matrix effect observed, and the response is linear at least up to 9.3 microg/mL of antimony. The sensitivity of the method is 2.609 x 10(-2) mL/microg, whereas the limits of detection and quantification are, respectively, 0.2 and 0.6 microg/mL. The repeatability, expressed as mean relative standard deviation of the measurements within the calibration range, is 2.0%, whereas the repeatability of the entire procedure is 0.3%. The mean analytical recovery within the calibration range was 102.6%. The method was successfully applied to river water samples.

Role of T cells in non-immediate drug allergy reactions.

PURPOSE OF REVIEW: Nonimmediate drug hypersensitivity reactions (NI-DHR) constitute the most complex group of drug allergy, with many drugs involved. Both parent drugs and their reactive metabolites can be implicated. Although with some drugs the number of metabolites is limited, with others it is quite extensive and many still remain to be identified. The diagnostic approaches are insufficient for the diagnosis and realistic approaches that reproduce the pathological response are lacking. RECENT FINDINGS: A wider view has now been considered, with the inclusion of several mechanisms that may contribute to drug hypersensitivity reactions (DHR): the classical hapten hypothesis, the danger signal and the pharmacological interaction. Monitoring the acute response provides relevant information about the mechanisms involved, with the identification of a large number of genes that can be over-expressed or under-expressed in the acute phase of the response. Assessment of risk of developing reactions can be verified by HLA associations. SUMMARY: Further knowledge of these NI-DHR, including molecular genetics and transcriptomic analysis, has enabled a better understanding and management of these reactions.

Eosinophilic Esophagitis: Review and Update.

Background: Eosinophilic esophagitis (EoE) was first described in the 1990s, showing an increasing incidence and prevalence since then, being the leading cause of food impaction and the major cause of dysphagia. Probably, in a few years, EoE may no longer be considered a rare disease. Methods: This article discusses new aspects of the pathogenesis, symptoms, diagnosis, and treatment of EoE according to the last published guidelines. Results: The epidemiological studies indicate a multifactorial origin for EoE, where environmental and genetic factors take part. EoE affects both children and adults and it is frequently associated with atopic disease and IgE-mediated food allergies. In patients undergoing oral immunotherapy for desensitization from IgE-mediated food allergy the risk of developing EoE is 2.72%. Barrier dysfunction and T-helper 2 inflammation is considered to be pathogenetically important factors. There are different patterns of clinical presentation varying with age and can be masked by adaptation habits. Besides, symptoms do not usually correlate with histologic disease activity. The diagnostic criteria for EoE has evolved but mainly requires symptoms of esophageal dysfunction with histologic evidence of a peak value of at least 15 eosinophils per high-power field. Endoscopies have to be repeated in order to diagnose, monitor, and treat EoE. Treatment of EoE can be started either by drugs (PPIs and topical corticosteroids) or elimination diets. The multistage step-up elimination diet management approach of EoE is promising. Endoscopic dilation is used for patients with severe dysphagia/food impaction with inadequate response to anti-inflammatory treatment. Conclusions: Research in recent years has contributed to a better understanding of EoE's pathogenesis, genetic background, natural history, allergy workup, standardization in assessment of disease activity, evaluation of minimally invasive diagnostic tools, and new therapeutic approaches. However, several unmet needs are to be solved urgently, as finding a non-invasive disease-monitoring methods and biomarkers for routine practice, the development or new therapies, novel food allergy testing to detect triggering foods, drug, and doses required for initial therapy and safety issues with long-term maintenance therapy, amongst others. Besides, multidisciplinary management units of EoE, involving gastroenterologists, pediatricians, allergists, pathologists, dietitians, and ENT specialists are needed.

High-Power 365 nm UV LED Mercury Arc Lamp Replacement for Photochemistry and Chemical Photolithography.

Ultraviolet light emitting diodes (UV LEDs) have become widespread in chemical research as highly efficient light sources for photochemistry and photopolymerization. However, in more complex experimental setups requiring highly concentrated light and highly spatially resolved patterning of the light, high-pressure mercury arc lamps are still widely used because they emit intense UV light from a compact arc volume that can be efficiently coupled into optical systems. Advances in the deposition and p-type doping of gallium nitride have recently permitted the manufacture of UV LEDs capable of replacing mercury arc lamps also in these applications. These UV LEDs exceed the spectral radiance of mercury lamps even at the intense I-line at 365 nm. Here we present the successful exchange of a high-pressure mercury arc lamp for a new generation UV LED as a light source in photolithographic chemistry and its use in the fabrication of high-density DNA microarrays. We show that the improved light radiance and efficiency of these LEDs offer substantial practical, economic and ecological advantages, including faster synthesis, lower hardware costs, very long lifetime, an >85-fold reduction in electricity consumption and the elimination of mercury waste and contamination.

Phenolic components and antioxidant activity of Fernblock, an aqueous extract of the aerial parts of the fern Polypodium leucotomos.

Fernblock, an aqueous extract of the aerial parts of the fern Polypodium leucotomos, used as raw material for topical and oral photoprotective formulations, was fractioned by HPLC and the main components with antioxidant capability were identified by means of UV spectra, electrochemical detection, and MSn. Phenolic compounds were identified as 3,4-dihydroxybenzoic acid, 4-hydroxybenzoic acid, vanillic acid, caffeic acid, 4-hydroxycinnamic acid, 4-hydroxycinnamoyl-quinic acid, ferulic acid, and five chlorogenic acid isomers. Total ferric antioxidant capacity (FRAP) of HPLC eluted fractions was measured. The results suggest that the herein identified compounds support, at least partially, the antioxidant and radical scavenging capacities of Fernblock.

That's easy for you to say: action identification and speech fluency.

Action identification theory holds that an action can be identified by the performer in different ways, and that these various act identities differ in their appropriateness for maintaining the action effectively. Optimal action identification exists when a personally easy action is identified in relatively high-level terms (i.e., the action's effects and implications) or a personally difficult action is identified in relatively low-level terms (i.e., the action's mechanical details). To test the optimality hypothesis with respect to speech fluency, subjects were asked to deliver a speech to either an easy-to-persuade audience or a difficult-to-persuade audience and induced to think about the action in either high-level or low-level terms. As predicted, subjects made fewer speech errors and felt more satisfied with their performance when the task was personally easy and identified at high level and when the task was personally difficult and identified at low level. Optimal action identification made things easier for them to say.

[The treatment of upper digestive hemorrhage of peptic origin: intravenous ranitidine versus intravenous omeprazole]. / Tratamiento de la hemorragia digestiva alta de origen péptico: Ranitidina intravenosa versus Omeprazol intravenoso.

OBJECT: To evaluate the effectiveness of Ranitidine i.v. versus Omeprazole i.v. for gastrointestinal bleeding of peptic origin. MATERIAL AND METHODS: Prospective, comparative, randomized and open study of 81 in-patients, hospitalized consecutively during 13 months, with gastrointestinal bleeding of peptic origin and signs of recent hemostasis (S.R.H.), belonging to the groups Forrest Ib and II. Treatment groups: group A: Ranitidine: initial injection of 50 mg. i.v., followed by 100 mg/6 hours i.v., during the first 72 hours and afterwards by 150 mg/12 hours, orally; group B: Omeprazole: initial injection of 80 mg. i.v., followed by 40 mg/8 hours i.v. during the first 72 hours and afterwards by 20 mg/24 hours, orally. Evaluation criteria: persistent haematemesis and melena; need for transfusions: treatment failure average period of hospitalization and disappearance of S.R.H. after 72 hours. RESULTS: 43 patients received Ranitidine and 38 Omeprazole. Both groups were homogeneous in regard to variables ar hospitalization. No significant differences were found between these two groups: persistent melena (26% group A vs. 8% group B); patients who needed transfusion (39% vs. 31%); treatment failure (19% vs. 5%); average period of hospitalization; and disappearance of S.R.H. (81% vs. 95%). None of the patients died. CONCLUSIONS: The effectiveness of Ranitidine i.v. and Omeprazole i.v., in the dosage used and in a selected group of patients with gastrointestinal bleeding, is similar. However, there is a trend to register less treatment failures and a higher percentage of S.R.H. disappearance with the patients treated with Omeprazole. Further studies with more patients are necessary to confirm this tendency.

[Electrophysiology in neuropathy caused by vincristine]. / Estudio electrofisiólogico en la neuropatía por vincristina

Ten patients treated with vincristine were submitted for electrophysiological examination. It was investigated the number of motor units within the thenar muscle following a technique described previously (Sica et al. - 1974); motor and sensitive conduction velocities as well as motor distal latencies in the median nerve were studied following conventional techniques. The behaviour of the evoked muscle potential with repetitive supramaximal stimulation over the median nerve was also investigated. The findings were compared with control groups. The estimated number of motor units was disminished in eight of ten patients and the average number was significantly different from the control group (control 318 +/- 71 UM; patients 174 +/- 84 UM; P less than 0.001). The potential amplitudes in most of the surviving units were reduced, others remaining within the normal range. This makes apparent that the peripherical nervous system fails to compensate adequately and, furthermore, a loss of individual muscle fibres occurs within some individual units. The conduction velocities of the fastest conducting motor nerve fibres were reduced and motor distal latencies prolongued (Table 1). Maximal impulse conduction velocities were measured in sensory fibres. In 5 of 7 subjets investigated the values laied just beyond the lower limit of the normal range. The amplitude of the sensory orthodromic evoked potential in the median nerve at the wrist was disminished almost in the whole group. The decremental muscle response to repetitive nerve stimulation, can be interpreted as the result of the damage at the neural apparatus at the motor end plate; it was observed in 57% of the patients. In summary, evidences have been registered showing that the nervous supply to the muscle is affected in patients treated with vincristine; the motor unit behaviour under this conditions is discussed.

Clinical features, etiology, and outcomes of community-acquired pneumonia in patients with diabetes mellitus.

We performed an observational analysis of a prospective cohort of immunocompetent hospitalized adults with community-acquired pneumonia (CAP) to determine the epidemiology, clinical features, and outcomes of pneumonia in patients with diabetes mellitus (DM). We also analyzed the risk factors for mortality and the impact of statins and other cardiovascular drugs on outcomes. Of 2407 CAP episodes, 516 (21.4%) occurred in patients with DM; 483 (97%) had type 2 diabetes, 197 (40%) were on insulin treatment, and 119 (23.9%) had end-organ damage related to DM. Patients with DM had different clinical features compared to the other patients. They were less likely to have acute onset, cough, purulent sputum, and pleural chest pain. No differences in etiology were found between study groups. Patients with DM had more inhospital acute metabolic complications, although the case-fatality rate was similar between the groups. Independent risk factors for mortality in patients with DM were advanced age, bacteremia, septic shock, and gram-negative pneumonia. Patients with end-organ damage related to DM had more inhospital cardiac events and a higher early case-fatality rate than did the overall population. The use of statins and other cardiovascular drugs was not associated with better CAP outcomes in patients with DM. In conclusion, CAP in patients with DM presents different clinical features compared to the features of patients without DM.

A computerized system for learned helplessness experiments.

A microcomputer-based system for carrying out learned helplessness experiments is described. The hardware is inexpensive and easily available. The program is written in BASIC and must be executed in the compiled form in order to keep up with real-time events. It contains an algorithm for calculating inter-trial intervals and allows the experimentor to freely select experimental conditions such as duration of shock, number of trials, etc. The task that the rat is required to do to stop the shock is also selectable, thus giving the experimentor the opportunity to maximize behavioral differences between escapable and inescapable rats while these differences are being induced. Experimental data on 12 rats that went through this automated protocol are analyzed and discussed.

Conscious compensations for thought insertion.

Thought insertion and other experiences of alien control have been explained as a source monitoring deficit, that results from a disconnection between a cognitive system for willed actions and a different system that monitors them. The case we present is a schizophrenic patient that in order to consciously avoid feeling his thoughts as not belonging to himself performs them as a motor act of speech. We suggest an interpretation for this conscious compensation following C. Frith's neuropsychological model of schizophrenia.