Effect of red blood cell preservation by droplet freezing with non-permeable cryoprotective agents in blood group antigen reactivity.

BACKGROUND: In the last few decades, various red blood cell (RBC) freezing techniques have been developed and improved to enable the preservation of erythrocytes for future use in pre-transfusion tests in reference immunohaematology laboratories. However, not all these techniques have been sufficiently evaluated for the preservation of blood group antigens. OBJECTIVES: In this study, we evaluated the antigenic pattern of RBCs preserved by droplet freezing in liquid nitrogen in a blood bank context. METHODS: Blood samples were evaluated for the reactivity of blood group antigens after droplet freezing using the non-permeable cryoprotective agent polyvinylpyrrolidone (PVP) and sucrose-dextrose (S + D) solutions. RESULTS: No qualitative changes were observed in RBC reactivity after freezing and thawing for the antigens Fyb , Leb , C, E, Cw , Lua , Lub , Kpa , Kpb and Dia . However, cryopreservation using PVP resulted in a significant increase in reactivity of Fyb antigen on comparing fresh and frozen samples (P < 0·001). CONCLUSION: The establishment of detailed protocols for cryopreservation of RBCs, which take into account the maintenance of antigenic characteristics, is necessary to increase security in pre-transfusion testing using frozen RBCs.

Antimicrobial activity of two techniques for arm skin disinfection of blood donors in Brazil.

OBJECTIVE: Evaluation of the antimicrobial effect of skin disinfection techniques is essential to avoid the transmission of infectious agents during blood transfusion. The aim of this study was to examine the effectiveness of two methods of arm skin disinfection used in blood donors at a Hemotherapy Center in Brazil that represents an important centre for distributing haemocomponents to many cities in the country. METHODS: Two skin disinfection techniques in 50 blood donors were evaluated. For the first arm, 10% povidone-iodine/two-stage technique was used. On the opposite arm, 0.5% chlorhexidine digluconate alcohol solution/one-stage technique was used. The swabs were seeded on three culture media: blood agar, mannitol salt agar and Mac Conkey agar. Automated bacterial classification based on biochemical tests/specific substrates was performed. Donor characteristics were collected using the computerised system of the Hemotherapy Center. RESULTS: We found that microbial reduction was significantly higher for 10% povidone-iodine technique (98.57-98.87%) when compared with 0.5% chlorhexidine technique (94.38-95.06%). The species Leuconostoc mesenteroides and Staphylococcus hominis showed resistance to both disinfection techniques. We did not find statistically significant relationships between donor characteristics and microbial reduction. CONCLUSIONS: Arm skin disinfection with 10% povidone-iodine produced better antimicrobial activity. We must acknowledge that 10% povidone-iodine technique has the limitation of being a two-stage method. However, prevention of adverse events due to bacterial contamination and transfusion reactions should be prioritised. Production of hypoallergenic and stronger antiseptics that allowed a safe one-stage disinfection technique should be encouraged in health systems, not only in Brazil but also around the world.

The EEG assessment of low-grade hepatic encephalopathy: comparison of an artificial neural network-expert system (ANNES) based evaluation with visual EEG readings and EEG spectral analysis.

OBJECTIVE: The EEG provides an objective staging of hepatic encephalopathy (HE), but its interpretation may be biased by inter-observer variability. This study aims at comparing an entirely automatic EEG classification of HE based on an artificial neural network-expert system procedure (ANNES) with visual and spectral analysis based EEG classifications. METHODS: Two hundred and thirty-eight consecutive cirrhotic patients underwent closed-eye EEG. They were followed up for up to one-year to detect bouts of overt HE and death. The EEG was classified by ANNES, qualitative visual reading, main basic rhythm frequency and spectral analysis. The classifications were assessed on the basis of: (i) match with liver function, (ii) prognostic value and (iii) repeatability. RESULTS: All classifications were found to be related to the severity of liver failure, with cognitive findings and a history of previous bouts of HE. All of them had prognostic value on the occurrence of overt HE and on survival. The ANNES based classification was more repeatable than the qualitative visual one, and had the advantage of detecting low power EEG, but its efficiency in analyzing low-grade alterations was questionable. CONCLUSIONS: An entirely automatic - ANNES based - EEG classification of HE can improve the repeatability of EEG assessment, but further improvement of the device is required to classify mild alterations. SIGNIFICANCE: The ANNES based EEG grading of HE needs further improvements to be recommended in clinical practice, but it is already sufficient for detecting normal and clearly altered EEG tracings.

Electroencephalographic staging of hepatic encephalopathy by an artificial neural network and an expert system.

AIM OF THE STUDY: To provide an objective EEG assessment of hepatic encephalopathy (HE), we set up and tested an entirely automatic procedure based on an artificial neural network-expert system software (ANNESS). PATIENTS AND METHODS: A training set sample of 50 EEG (group A) and a test sample of 50 EEG (group B) of 100 cirrhotic patients were considered. The EEGs had been visually classified by an expert electroencephalographer, using a modified five-degree Parsons-Simith classification of HE. The efficiency of the ANNESS, trained in group A, was tested in group B. RESULTS: Both the ANNESS and the visually-based classifications were found to be correlated to liver insufficiency, as assessed by the Child-Pugh score (Spearman's coefficient rho=0.485, P<0.0001; rho=0.489, P<0.0001, respectively) and by the biochemical indexes of hepatic function (bilirubin: rho=0.31 vs. 0.27; albumin: rho=-0.13 vs. -0.18; prothrombin time rho=-0.35 vs. -0.52). The classifications were found to be correlated to each other (rho=0.84 P<0.0001, Cohen's kappa=0.55). However, the ANNESS overestimated grade 2 EEG alterations. CONCLUSION: An ANNESS-based classification of EEG in HE provided data comparable with a visually-based classification, except for mild alterations (class 2) that tended to be overestimated. Further optimization of automatic EEG staging of HE is desirable, as well as a prospective clinical evaluation.

[Criteria for classification of upper limb work-related musculo-skeletal disorders due to biomechanical overload in occupational health. Consensus document by an Italian Working Group]. / Criteri per la trattazione e la classificazione di casi di malattia da sovraccarico biomeccanico degli arti superiori nell'ambito della medicina del lavoro. Documento di consenso di un gruppo di lavoro nazionale.

BACKGROUND AND OBJECTIVE: In a preliminary consensus document the authors proposed criteria and methods to identify upper limb work-related MSDs due to biomechanical overload. With this document they intend to define severity according to shared models and procedures so as to fit behaviours to diagnostic procedures and their medical-legal assessment. This becomes especially important in view of Ministerial Decree of April 27 2004 fixing the new lists of diseases having a possible work-related origin that must be reported by law in accordance with art. 139 of law n. 1124, and also on account of the impact of such diseases which, for the first time in Italy, are regulated by law. CONTENTS: The working group, which included INAIL and ISPESL experts and was fully supported by SIMFER (Italian Society of Physical Medicine and Rehabilitation) and SINC (Italian Society of Clinical Neurophysiology), defined a general clinical procedure (anamnesis, objective examination and instrumental assessment) regarding each portion of the concerned upper limb (shoulder, elbow and wrist/hand). Once the presence and characteristics of anatomic and functional damages are established, the results allow a classification scheme to be proposed of upper limb diseases (tendon disorders and entrapment neuropathy) divided into 6 increasing severity stages: initial, medium, medium-severe, severe and extremely severe. Special attention was paid to two instrumental examinations that proved to be of great clinical interest, at least in occupational health: echography of soft tissues (in appendix) and electroneurography for entrapment neuropathy. The limitations of this proposal are discussed but the main goal was achieved: to standardize terms and provide homogeneous criteria to achieve classification of upper limb damage due to biomechanical overload for increasing severity levels. The working group research activity is part of a research project funded by ISPESL.

Carpal tunnel syndrome: which electrodiagnostic path should we follow? A prospective study of 100 consecutive patients.

We prospectively studied 100 consecutive patients (200 hands) sent to our Neurophysiopathology Service for a suspected Carpal Tunnel Syndrome (C.T.S.). We performed 6 different motor and sensitive electrodiagnostic tests on both hands of each patients and on 25 healthy subjects. We calculated the sensibility and the specificity of each test by comparing each parameter with all the other ones, and then, again, using the clinical evaluation as a "gold standard". The routinely performed tests proved to have a high sensibility in detecting C.T.S., nevertheless, sometimes they do not give a definite response. In these cases we suggest to carry out the neurophysiological examination by performing some of the newly proposed tests. We end our study by drawing a "flow-chart", which considers reliability, sensibility, difficulty in performing and/or evaluating, and discomfort for patients, of each test; by this we would give a guide and a practical aid in determining the electrophysiological path for C.T.S. diagnosis.

Brachial plexus injuries. Guidelines for management: our experience.

In spite of the progress made by microneurosurgery, the treatment of brachial plexus injuries still remains a great challenge. This personal series of 49 patients with brachial plexus injuries (excluding tumours and thoracic outlet syndromes) is peculiar because the cases arose after the introduction in Italy of the law requiring all motorcyclists to wear a safety helmet. Our experience confirms that there has been a 32% increase in very severe almost irreparable injuries of the plexus in comparison with previous data reported in the literature. This is probably due to the higher rate of survival among severely-injured patients, although the possibility of a direct effect of the helmet on the plexus cannot be completely discarded. Our results confirm the good prognosis of the microsurgical repair of C5-C6 stretch injuries and infraclavicular lesions.

Tarsal tunnel syndrome. Report of a case and review of clinical and surgical aspects.

We describe a case of tarsal tunnel syndrome treated surgically. We analyze the principal etiopathogenetic and clinical features of the syndrome together with the surgical anatomy and go on to discuss the main steps in the surgical operation, the results and possible postoperative complications.

VEP and EEG in cortical blindness: a case with a complicated course.

We report a case of cortical blindness secondary to an extensive bilateral occipital ischemic infarct and complicated by the onset of bilateral optic nerve ischemia. We discuss the behavior of the VEP, present--an unusual finding--in the first phase of the occipital ischemic lesion, and the value of the alpha band rhythm in the EEG record.

[Somatesthesic, auditory and visual evoked potentials in chronic alcoholics]. / I potenziali evocati somestesici, uditivi, visivi, negli etilisti cronici.

The Authors examine a group of alcoholics, recording for each patients somatosensory, auditory and visual potentials, in order to check the presence in different systems of nervous fibers of subclinic alterations; they separate a group of patients with clinic polyneuropathie and a group without polyneuropathie. Subclinic alterations are confirmed in different measure in the two groups. Vit. B12 and pholic acid are also dosed in the serum.

[Method of measuring spasticity. Studies of 12 cases of spastic patients treated with chronic epidural implanted electrodes]. / Metodo di misura della spasticità. Indagine su 12 casi di pazienti spastici, trattati con impianto epidurale cronico di elettrodi.

The Authors have applied the method for determination of the H reflex, in order to measure the spasticity in a group of patients operated with chronic implantation of epidural electrodes. After a brief discussion about a clinical and neurophysiological problems of the spasticity, they refers the methodologie and results obtained by determination of H/M ratio and H1/H2 curve with double stimulus. They conclude that this method is rather uncertain and useful only at a approximative clinical level.

[Early evoked auditory potentials in transient ischemic attacks of the posterior circle of Willis]. / I potenziali uditivi evocati precoci nei T.I.A. del circolo posteriore.

The authors studies through the evoked potentials of the brain stem a group of patients affected from T.I.A. of the vertebro-basilar circulation. From the remarks of cases this examination results significant in 66%. The more characteristic remarks is the increase of absolute latency of V wave. It is also possible to follow contemporary the evolution of auditive brain pathways disease and clinical features in repeating the test.

[Evoked somatosensory plexus and cervical evoked potentials in cervicobrachialgia]. / I potenziali evocati somato-sensitivi plessuali e cervicali nelle cervicobrachialgie.

The authors study the sensitive potential evoked from point of Erb and from cervical spine in C6-C7, obtained by stimulation of median nerve in a control group (normals) and in a greater group of 40 cases from patients affected by radiculopathie with or without discal protrusion and by myelopathie spondiloartrosic. The date supply significant informations and are (obicurred in analytique) analyzed with accuracy.

Effects of hemodialytic treatment on uremic polyneuropathy. A clinical and electrophysiological follow-up study.

The involvement of peripheral motor and sensory nerve, at least on a subclinical level, is nearly constant event with chronic renal failure. The study of the motor and sensory propagation velocity indicates that a widespread functional lesion of the axon with a peripheral point of attack and secondary demyelination, may be the basic pathogenetic event of uremic polyneuropathy. Prolonged hemodialytic treatment is substantially unable to influence the evolution of uremic polyneuropathy. The electrophysiological follow-up study of the peripheral nerve does not seem to be an index of adequate dialysis.

Vincristine polyneuropathy in man. A clinical and electrophysiological study.

A clinical and electrophysiological follow up study of 14 cases of hemopathic patients patients undergoing VCR therapy showed evidence that the drug has a direct action on the motor and sensory axon but not on the propagation velocity. Sensory nerves seem to be affected earlier and more than motor ones. Correlation was good between clinical and electrophysiological findings for both functions. The findings in man correspond with the animal data and therefore lead to the conclusion that VCR polyneuropathy is due to an involvement of the nerve axon.