[Molecular mimicry between Plasmodium sp and Guillain-Barre syndrome antigens]

OBJECTIVE

Analyze the molecular mimicry between Plasmodium spp. and autoantigens associated with GBS, identifying possible antigenic epitopes.

METHODS

PSI-Blast, Praline, Emboss, Protein Data Bank, Swiss Model Server, AlphaFold 2, Ellipro and PyMol 2.3 were used to search for homologies, perform alignments, obtain protein structures, and predict epitopes.

RESULTS

17 autoantigens and seven immunological targets of the peripheral nervous system were included, identifying 72 possible epitopes associated with GBS. From the proteome of Plasmodium spp. (298 proteins), only two showed similarities close to 30% with TRIM21 and BACE1, generating seven possible epitopes.

CONCLUSION

No significant homologies were observed between the proteome of GBS and Plasmodium spp. The exploration of other mechanisms such as immune-mediated capillary damage, Epitope Spreading or Bystander Activation is suggested to explain the mentioned association. These findings underscore the need to clarify the etiology of autoimmune diseases and the role of pathogens. The need for experimental studies to validate these results is emphasized.

Prevalence, Identity, Pathogenicity, and Infection Dynamics of Botryosphaeriaceae Causing Avocado Branch Canker in California

Botryosphaeria branch canker and dieback of avocado (Persea americana Mill.) has expanded in avocado-growing areas in recent years. Twenty-one avocado groves in the major producing regions of California were surveyed in 2018 and 2019. Monthly inoculations of wounded, green, and lignified branches of 'Hass' and 'Lamb Hass' were conducted. Botryosphaeriaceae were the predominant fungi recovered from cankered tissues collected across the surveyed traditional and high-density orchards and caused symptoms on all six sampled cultivars. These fungi were also recovered in asymptomatic twigs and other organs and thus exist as a potential reservoir for future infections. Molecular analyses of 173 isolates showed that Neofusicoccum luteum had the greatest incidences across sites and cultivars, with 83 and 29% recovered from Hass and Lamb Hass, respectively. Pathogenicity tests on excised (Hass, GEM, and Hass mutants) and attached shoots from potted (Hass) and mature avocado trees (Hass and Lamb Hass) showed that all species were pathogenic on wounded, green, and mature branches of the specified cultivars. Monthly inoculations of wounded, green, and lignified branches of Hass and Lamb Hass showed that both stem types were susceptible throughout the inoculation periods, regardless of the avocado phenological stage. In temperature-dependent growth and infection studies, growth of three points could vary during the growing season. Botryosphaeriaceae grown was higher between 20 and 30°C, but only Lasiodiplodia theobromae significantly grew and caused external lesions at 35°C. Lasiodiplodia theobromae also grew more on perseitol-amended media, all indicating its adaptation to warmer temperatures and capacity in metabolizing the avocado-produced sugar. Overall, this study extended our knowledge of the prevalence, identity, and pathogenicity of Botryosphaeriaceae on avocado cultivars, which will be useful to tailor management strategies.

Leadless pacemaker patients following cardiac valve intervention in a long-term follow-up

Introduction

Leadless pacemakers (LPM) have demonstrated adequate electrical performance and safety in patients with multiple commorbidities such as heart valve replacements at short-term follow-up.

Purpose

We present our experience in patients with LPM and heart valve replacements at long-term follow-up.

Methods

This was a prospective observational study including all consecutive LPM implantation from June 1 2005 to March 15 2021. Clinical, electrical, echocardiographic characteristics, related complications and electrical parameters were compared in 2 different groups with and with-out valve surgical procedure.

Results

A total of 255 LPM were implanted. Clinical, electrical and echocardiographic characteristics are described in table 1. Mean follow-up was of 24 months. There were no significant differences in electrical performance or related complications in between both groups (Figure 1).

Conclusions

Electrical performance and complications were no significantly different between both groups with and without heart valve replacements.

Funding Acknowledgement

Type of funding sources: None.

Efficacy and quality of life after transcutaneous posterior tibial neuromodulation for faecal incontinence

AIM

The aim of this study was to evaluate the efficacy of transcutaneous neuromodulation of the posterior tibial nerve for faecal incontinence and to assess quality of life after the procedure.

METHOD

A prospective non-randomized cohort study was conducted in a tertiary centre from September 2010 to May 2013. All patients with faecal incontinence who met the inclusion criteria were included and were treated as outpatients during a 3-month period by unilateral neuromodulation of the posterior tibial nerve. The patients were followed 3-monthly for 1 year. Severity scales, a bowel diary and quality of life scales were evaluated prospectively before and after treatment.

RESULTS

Twenty-seven patients of median age 67 (interquartile range 60-69) years and a male to female ratio of 1/6 were included. Faecal incontinence was for solid stools in 48.1% of patients with urgency in 55.6%. About one-third (34.6%) had a sphincter defect on ultrasound and reduction of anal canal pressure in 85.2%. There was a significant improvement in episodes of incontinence on the Wexner score and visual analogue scale assessment and a decrease in the number of episodes of incontinence per unit time. The Fecal Incontinence Quality of Life score was improved at the end of the follow-up. No adverse effects were observed. The cost of the treatment was €135 per patient.

CONCLUSION

Transcutaneous posterior tibial nerve neuromodulation provides good treatment for faecal incontinence in terms of efficacy and quality of life.

Layered exfoliable crystalline materials based on Sm-, Eu- and Eu/Gd-2-phenylsuccinate frameworks. Crystal structure, topology and luminescence properties

New layered 2D MOFs based on 2-phenylsuccinate, Sm, Eu and Eu/Gd are a suitable platform for obtaining exfoliatable frameworks with luminescence properties for potential applications as thin films.

Magnetoresistance effect in (La, Sr)MnO3 bicrystalline films

The angular dependence of the magnetoresistance effect has been measured on bicrystalline La(0.75)Sr(0.25)MnO(3) films. The measurements have been performed on an electronically lithographed Wheatstone bridge. The study of the angular dependence of both the magnetoresistance and the resistance of single-crystalline and grain-boundary regions of the samples allowed us to isolate two contributions of low-field magnetoresistance in manganites. One of them is associated with the spin-orbit effect, i.e. the anisotropic magnetoresistance of ferromagnetic compounds, and the other one is related to spin-disorder regions at the grain boundary. Complementary x-ray diffraction, ferromagnetic resonance and low temperature magnetization experiments contribute to the characterization of the magnetic anisotropy of the samples and the general comprehension of the problem.

Voltammetry and amperometric detection of tetracyclines at multi-wall carbon nanotube modified electrodes

The voltammetric behaviour and amperometric detection of tetracycline (TC) antibiotics at multi-wall carbon nanotube modified glassy carbon electrodes (MWCNT-GCE) are reported. Cyclic voltammograms of TCs showed enhanced oxidation responses at the MWCNT-GCE with respect to the bare GCE, attributable to the increased active electrode surface area. Hydrodynamic voltammograms obtained by flow-injection with amperometric detection at the MWCNT-GCE led us to select a potential value E(det) = +1.20 V. The repeatability of the amperometric responses was much better than that achieved with bare GCE (RSD ranged from 7 to 12%), with RSD values for i (p) of around 3%, thus demonstrating the antifouling capability of MWCNT modified electrodes. An HPLC method with amperometric electrochemical detection (ED) at the MWCNT-GCE was developed for tetracycline, oxytetracycline (OTC), chlortetracycline and doxycycline (DC). A mobile phase consisting of 18:82 acetonitrile/0.05 mol L(-1) phosphate buffer of pH 2.5 was selected. The limits of detection ranged from 0.09 micromol L(-1) for OTC to 0.44 micromol L(-1) for DC. The possibility to carry out multiresidue analysis is demonstrated. The HPLC-ED/MWCNT-GCE method was applied to the analysis of fish farm pool water and underground well water samples spiked with the four TCs at 2.0 x 10(-7) mol L(-1). Solid-phase extraction was accomplished for the preconcentration of the analytes and clean-up of the samples. Recoveries ranged from 87 +/- 6 to 99 +/- 3%. Under preconcentration conditions, limits of detection in the water samples were between 0.50 and 3.10 ng mL(-1).

Delta opioid receptor localization in the rat cerebellum

Opioid receptors have been localized to a number of brain regions in rats as well as in other species. In situ hybridization has demonstrated the presence of mRNA for the delta receptor subtype in adult rat cerebellar cortex and in several deep nuclei, but there are no reports on localization of the delta receptor protein in cerebellar regions. In the present study, both quantitative immunohistochemistry and Western blots reveal the presence of delta receptors in the adult rat cerebellum, using a specific affinity-purified antibody. Purkinje cells and processes, as well as cells in the granule cell layer, were positively stained with the antibody. Quantitation of confocal microscopy images illustrated a lower relative level of delta receptor immunoreactivity in cerebellar cortical neurons as compared to neurons in hippocampal regions, striatum and cerebral cortex. Stimulation of delta receptors with a selective agonist, DPDPE, in frozen sections of rat brain, induced a significant increase in binding of [35S]-GTPgammaS in the cerebellar cortex as compared to basal binding levels, thereby demonstrating coupling of the receptor subtype to G-protein. Functional implications for the delta receptor in the cerebellum are discussed, particularly in light of evidence for the presence of a cerebellar opioid receptor for the endogenous opioid methionine enkephalin during early postnatal life.

Brachial-jugular expanded PTFE grafts for dialysis

The objective of this study was to analyze the long-term outcome of 51 patients with brachial-jugular grafts for dialysis. Age, presence of diabetic nephropathy, complications of the angio-access, and therapeutic methods of treating complications were analyzed. All surgical procedures were performed under local anesthesia in an ambulatory surgical setting. The duration of angio-access was analyzed using the life-table method. Our results showed that brachial-jugular grafts can be performed under local anesthesia and in an ambulatory surgical setting. This procedure can be an alternative to complex intrathoracic procedures, Dacron cuff catheters, or lower limb grafts, in cases of stenosis or occlusion of the subclavian vein.

1-(2-[4-[6-Hydroxy-2-(4-hydroxyphenyl)benzo[b]thiol-3-ylcarbonyl]phenoxy]ethyl)piperidinium chloride

The title compound, raloxifene hydrochloride, C(28)H(28)NO(4)S(+).-Cl(-), belongs to the benzothiophene class of antiosteoporotic drugs. In the molecular cation, the 2-phenol ring sustains a dihedral angle of 45.3 (1) degrees relative to the benzo[b]thiophene system. The benzo[b]thiophene and phenyl ring planes are twisted with respect to the carbonyl plane, with the smallest twist component occurring between the phenyl and carbonyl planes. The N atom bears the positive charge in the molecular cation and the piperidine ring adopts an almost perfect chair conformation. The Cl(-) anion is involved in the formation of N-H...Cl and O-H...Cl intermolecular hydrogen bonds, which lead to the formation of a layer of molecular cations.

Ketazolam

The title compound, 11-chloro-8,12b-dihydro-2,8-dimethyl-12b-phenyl-4H-[1,3]oxazino[3,2-d][1,4]benzodiazepine-4,7(6H)-dione, C20H17ClN2O3, is a benzodiazepine with an additional d-face-fused heterocyclic ring. In the molecule, a dihedral angle of 86.2 (1) degrees is formed by the planes of the phenyl and benzo rings and the former is axially oriented from the core, i.e. the fused 6,7,6-tricyclic system. Both heterocycles in the core suffer significant deviations from planarity. The central diazepine ring is a twist-boat and the oxazine ring exhibits a conformation intermediate between half-chair and sofa.

Routine surveillance endomyocardial biopsy continues to detect significant rejection late after heart transplantation

BACKGROUND

The need for continued surveillance endomyocardial biopsies beyond the first year after cardiac transplantation is controversial. We evaluated the incidence of rejections requiring treatment (International Society Heart and Lung Transplantation grade 3A or greater) in patients 5 years or more after heart transplantation.

METHODS

We conducted a retrospective chart review of all patients who underwent at least 1 endomyocardial biopsy at our center 5 years or more after heart transplantation.

RESULTS

A total of 461 biopsies were performed in 77 patients 5 or more years after heart transplantation. Nine episodes of grade 3A or greater rejection were identified in 8 of 77 patients (10%). During the first year, 7.6% of biopsies were grade 3A or greater. Grade 3A rejection occurred in approximately 3.5% to 4% of biopsies during years 2 to 7. The overall incidence of procedural related complications at our institution was < 0.5%.

CONCLUSION

Endomyocardial biopsies continue to detect clinically significant rejection beyond 5 years after cardiac transplantation. The overall incidence of procedural related complications requiring treatment was low and none was life threatening. The absence of early rejection does not predict freedom from late rejection. Therefore, we continue to recommend surveillance biopsies in cardiac transplant recipients late after transplantation.

Triflusulfuron-methyl dissipation in water and soil

This paper reports laboratory studies of the behavior and fate of triflusulfuron-methyl in aqueous buffer and soils. Aqueous hydrolysis was pH-dependent and fast in acidic buffer solutions. In basic buffers, the hydrolysis rate variation was low between pH 7 and pH 10. The degradation pathway in the range of pH 4-10 was via cleavage of the sulfonylurea bridge to form two transformation products: 2-amino-4-(dimethylamino)-6-(2,2,2-trifluoroethoxy)-1,3, 5-triazine (2) and 6-methyl-2-methylcarboxylate benzene sulfonamide (3). Comparison of transformation rates in sterile and nonsterile soils indicates that chemical and microbial processes are important in soil degradation. The former is more important in acidic soils, and the latter is more important in basic soils. A biphasic model fits well with dissipation of triflusulfuron-methyl in soil. The triazine formed during the first step of transformation was degraded more rapidly in basic soils than in acidic soils.

1-[2-(1-Hydroxycyclohexyl)-2-(4-methoxyphenyl)ethyl]dimethylammonium chloride (venlafaxine hydrochloride)

The crystal structure of racemic Venlafaxine hydrochloride, C(17)H(28)NO(2)(+).Cl(-), consists of two types of parallel chains formed by translated Venlafaxine(+) cations, hydrogen bonded by Cl(-) anions, and characterized by the opposite chirality of their constituent molecules. These chains organize in two different types of broad layers of opposite handedness, related by a glide plane.

Unilateral breast enlargement secondary to right brachiocephalic vein occlusion

We describe a 56-year-old woman who received dialysis through a right jugular catheter and developed a progressive right breast enlargement 1 year after arteriovenous graft shunt construction in the right forearm. Arm edema was not observed. A fistulography showed retrograde long thoracic and lateral thoracic veins flow secondary to a right brachiocephalic vein occlusion. Breast enlargement disappeared completely 2 weeks after a transfemoral balloon angioplasty and stent placement.

[Evidence-based medicine in antimicrobial surgical prophylaxis]

INTRODUCTION

The main objective of antibiotic prophylaxis in surgery is to reduce morbidity and mortality associated with wound infection, which has a favorable impact on quality of care and overall health-care costs. The bases of antibiotic prophylaxis have been known for decades, but the appearance of new pharmacological agents, alternative routes of administration, modern surgical procedures, and previously unknown antimicrobial resistances involve the need for reviewing these bases.

OBJECTIVE

To re-evaluate some of the general principles of the use of antibiotic prophylaxis in surgery and highlight the quality of the evidence supporting our clinical decisions found in the literature.

METHOD

Review of the literature with special attention to prospective, randomized, evidence-based clinical trials on the need for antibiotic prophylaxis in surgery, mainly general surgery.

RESULTS

The method for demonstrating the effectiveness of an antibiotic in prophylaxis continues to be the prospective, randomized clinical trial. Evidence of the need for antibiotic prophylaxis in clean-contaminated surgery and when prosthetic materials are used is good.

CONCLUSIONS

Most studies on the general principles of prophylaxis have been carried out in general surgery and it is difficult to extrapolate their results to other fields or surgical specialties. Therefore, new clinical trials in each specialty are needed to establish specific recommendations. However, the standardization of aseptic, antiseptic, and technical procedures in surgery has produced a notable decrease in the wound infection rate compared to historical controls, so now it is difficult to demonstrate significant differences in the results of clinical trials. Finally, the response to the fundamental question of "What do we propose to prevent and to what degree?" with which the antibiotic era began is either difficult to formulate or described ambiguously when referring to advanced procedures, such as endoprostheses, endoscopic retrograde cholangiography, or dental implants.

Comparison of nebulized glycopyrrolate and metaproterenol in chronic obstructive pulmonary disease

We assessed the bronchodilating effect of glycopyrrolate (GP) and compared it with that of metaproterenol (MP), alone and in combination (GP+MP), in patients with chronic obstructive pulmonary disease (COPD). In a double-blind study, 11 patients (aged (mean +/- SD) 69 +/- 6 yrs; forced expiratory volume in one second (FEV1) 1.2 +/- 0.4 L) with stable COPD inhaled nebulized GP 1.0 mg, MP 15 mg, or GP 1.0 mg+MP 15 mg. Spirometry was performed before inhalation and at hourly intervals for 8 h after inhalation. It was found that GP produced a bronchodilating effect that was about equal to that of MP but lasted longer (8 vs 5 h). The combination of GP and MP produced a bronchodilating effect that was greater than that of either drug alone and was evident mostly during the effect of MP. The mean peak percentage improvement in FEV1 over baseline was 35% for GP+MP and 25% for either drug alone. These data suggest that nebulized glycopyrrolate is an effective bronchodilator in some patients with chronic obstructive pulmonary disease. Concurrent administration of glycopyrrolate and metaproterenol produces additional bronchodilation that is primarily apparent during the bronchodilator effect of metaproterenol.

Degradation of iprodione by a soil Arthrobacter-like strain

A bacterial strain able to transform iprodione was isolated from a fast iprodione-degrading soil by enrichment procedures. Transformation was detected through 3,5-dichloroaniline production as measured by a rapid colorimetric method. The strain, MA6, was tentatively identified as an Arthrobacter sp. When it was incubated with MA6 in a minimum mineral medium (pH 6.5), iprodione (8.8 mumol/liter) was transformed into two major metabolites that were identified by high-performance liquid chromatography analysis: 3,5-dichlorophenylcarboximide (metabolite 1) and (3,5-dichlorophenylurea) acetic acid (metabolite 2), which was produced after ring cleavage of the former product. These products were synthesized in the laboratory and compared with metabolites 1 and 2 which were formed during iprodione degradation. Small quantities of 3,5-dichloroaniline also appeared in the bacterial culture but did not substantially increase between the first and second days of incubation. In contrast, in the sterile control medium, iprodione was spontaneously transformed into hydantoic acid and an iprodione isomer. Chemical and biological transformations of iprodione seem to occur through two different pathways. One biological degradation pathway is proposed.

Haemophilus aphrophilus as a rare cause of arthritis

A case of septic arthritis due to Haemophilus aphrophilus is presented. This organism has rarely been reported as a cause of bone or joint infections. We believe this is the third reported case of septic arthritis caused by this microorganism. We review the clinical and bacteriologic findings and the previously reported cases of infection caused by H. aphrophilus. Treatment with ceftriaxone was followed by full recovery without sequelae.

Surgical repair of aortic root aneurysms in 280 patients

Bentall's technique for repair of annuloaortic ectasia has been associated with postoperative bleeding and with false aneurysms at the anastomotic site between the coronary orifices and valve-containing graft. To reduce the incidence of these complications, we modified the Bentall procedure, using a simplified technique to implant the graft and to create a fistula between the closed perigraft space and right atrium to control bleeding. A continuous suture of monofilament polypropylene was used to implant the prosthetic valve ring and to anastomose the coronary orifices to the Dacron fabric. In some instances, a brief period of hypothermic circulatory arrest was needed to perform the distal aortic anastomosis. Among 562 patients undergoing operation for aneurysm of the ascending aorta between January 1, 1980, and February 28, 1990, 280 underwent graft replacement with a valve-containing composite conduit. Most (82%) had annuloaortic ectasia. In 267, we performed a classic Bentall procedure with direct anastomosis between the coronary orifices and fabric graft. The remaining 13 patients underwent other procedures for coronary connection. Early mortality was 5.0%. Reoperation for bleeding was needed in 13.2% of patients who underwent operation before we used the right atrial fistula technique and in 4.4% after we began to use the technique (p = 0.044). Actuarial survival was 71% at 5 years and 65% at 7 years. For hospital survivors, it was 76% at 5 years and 70% at 7 years. During follow-up, only 9 patients have required reoperation. A false aneurysm at the coronary anastomosis, which was associated with prosthetic valve endocarditis, developed in 1 patient. No permanent fistulas have developed.(ABSTRACT TRUNCATED AT 250 WORDS)